KR102244391B1 - Compressor - Google Patents

Abstract

The compressor is started. The compressor according to the present specification includes a cylinder forming a compression space in which a piston is reciprocated in an axial direction to compress a refrigerant gas in a space formed inside a cylindrical cylinder body, and a cylinder is accommodated in a space formed therein. And a frame in which a gas hole is formed in which the side communicates with the outside to allow the refrigerant gas to flow in, and the other side communicates with the gas pocket including the space between the inner circumferential surface and the outer circumferential surface of the cylinder, and one side of the cylinder is in communication with the gas pocket. A gas inlet is formed in which the other side communicates with the space formed inside the cylinder, and the gas pocket is provided in a range of 10 to 30 micrometers between the inner peripheral surface of the frame and the outer peripheral surface of the cylinder.

Description

Compressor {Compressor}

This specification relates to a compressor. More specifically, it relates to a linear compressor for compressing a refrigerant by a linear reciprocating motion of a piston.

In general, a compressor refers to a device configured to compress working fluid such as air or refrigerant by receiving power from a power generating device such as a motor or a turbine. Compressors are widely applied to industry as a whole or home appliances, in particular, vapor compression refrigeration cycles (hereinafter referred to as'refrigeration cycles').

These compressors may be classified into a reciprocating compressor, a rotary compressor (rotary compressor), and a scroll compressor according to a method of compressing a refrigerant.

In the reciprocating compressor, a compression space is formed between the piston and the cylinder, and the piston linearly reciprocates to compress fluid, and the rotary compressor compresses the fluid by eccentrically rotating rollers inside the cylinder, and the scroll compressor is a spiral It is a method of compressing fluid by rotating a pair of scrolls made of.

Recently, among reciprocating compressors, the use of a linear compressor using a linear reciprocating motion without a crankshaft has been gradually increasing. The linear compressor has the advantage of having a relatively simple structure and improving the efficiency of the compressor because there is little mechanical loss associated with converting rotational motion to linear reciprocating motion.

In the linear compressor, a cylinder is positioned inside a casing forming a closed space to form a compression chamber, and a piston covering the compression chamber may be configured to reciprocate inside the cylinder. In a linear compressor, fluid in the closed space is sucked into the compression chamber while the piston is positioned at the bottom dead center (BDC), and the fluid in the compression chamber is sucked into the compression chamber when the piston is positioned at the top dead center (TDC). The process of being compressed and discharged is repeated.

Meanwhile, the linear compressor can be classified into an oil lubricated linear compressor and a gas type linear compressor according to a lubrication method.

As disclosed in Patent Document 1 (Korean Patent Laid-Open Publication No. 10-2015-0040027), the oil-lubricated linear compressor is configured to lubricate a cylinder and a piston using the oil by storing a certain amount of oil in the casing. On the other hand, as disclosed in Patent Document 2 (Korean Patent Laid-Open Publication No. 10-2016-0024217), the gas lubricated linear compressor guides part of the refrigerant discharged from the compression space without storing oil inside the casing between the cylinder and the piston. It is configured to lubricate the cylinder and the piston with the gas power of the refrigerant.

In the oil-lubricated linear compressor, as oil having a relatively low temperature is supplied between the cylinder and the piston, it is possible to suppress overheating of the cylinder and the piston due to motor heat or compression heat. Through this, the oil lubricated linear compressor can prevent the occurrence of suction loss by suppressing the increase in specific volume due to heating while the refrigerant passing through the suction passage of the piston is sucked into the compression chamber of the cylinder.

However, in the oil-lubricated linear compressor, if the oil discharged to the refrigeration cycle device along with the refrigerant is not smoothly recovered to the compressor, an oil shortage may occur inside the casing of the compressor. It may cause the reliability to deteriorate.

On the other hand, gas lubricated linear compressors are advantageous in that they can be downsized compared to oil lubricated linear compressors, and the reliability of the compressor due to oil shortage does not occur because the refrigerant lubricates the cylinder and the piston.

However, in the conventional gas lubricated linear compressor as described above, oil flows between the cylinder and the piston, resulting in a problem that the lubrication performance is rapidly deteriorated. In particular, the oil flowing into the sliding part acts like an air bag, or causes a phenomenon to push the piston to one side by generating a force from a high dynamic pressure. As a result, the piston comes into contact with the cylinder, which weakens the durability and reliability of the compressor.

Korean Patent Application Publication KR10-2015-0040027 A (published on April 14, 2015) Korean Patent Application Publication No. KR10-2016-0024217 A (published on March 4, 2016)

The present specification provides a compressor capable of preventing oil from flowing into a sliding part, and has an object thereof.

In addition, another embodiment of the present specification provides a compressor capable of performing a filter function while performing a restrictor function for reducing the pressure of the refrigerant flowing into the cylinder in the gas bearing system through a shape change of the cylinder or frame. I want to provide.

The compressor according to an embodiment of the present specification includes a cylinder formed inside a cylindrical cylinder body and forming a compression space in which a piston reciprocates in an axial direction to compress a refrigerant gas, and the cylinder in the space formed therein. And a frame in which a gas hole communicating with a gas pocket including a space between an inner circumferential surface and an outer circumferential surface of the cylinder is formed on the other side and the refrigerant gas is introduced by being in communication with the outside, and the cylinder is one A gas inlet portion is formed in which the side communicates with the gas pocket and the other side communicates with the space formed inside the cylinder, and the gas pocket has a distance of 10 to 30 micrometers between the inner circumferential surface of the frame and the outer circumferential surface of the cylinder. It can be provided in a range.

In this case, the frame includes a frame body having a cylindrical shape for accommodating the cylinder, and a frame flange extending radially outward from the front of the body and to which a driving unit driving the piston is connected, and the gas hole One side may communicate with the front of the frame flange and the other side may communicate with the inside of the frame body.

Here, the frame may further include a frame connection portion connecting the frame body and the frame flange, and the gas hole may penetrate the frame connection portion in a direction inclined to an axial direction.

In addition, a front sealing member interposed between the cylinder and the frame at the front of the gas hole to seal the front of the gas pocket, and interposed between the cylinder and the frame at the rear of the gas hole to seal the rear of the gas pocket And a rear sealing member, wherein the gas pocket may be provided as a space between the front sealing member and the rear sealing member.

Here, the gas inlet portion is formed to be concave radially inward from the outer circumferential surface of the cylinder, and a plurality of the gas inlet portions are provided in the axial direction, and any one of the plurality of gas inlet portions may be provided to partially overlap the other side of the gas hole. have.

In this case, the gas inlet may extend in a circumferential direction along the outer circumferential surface of the cylinder.

In addition, a gas receiving groove may be formed on the inner circumferential surface of the cylinder, which communicates with the gas inlet part, is concave outward in the radial direction, and is provided with a plurality of axial directions.

Here, the gas receiving groove may extend in the circumferential direction at an angle within 180 degrees with respect to the central axis along the inner circumferential surface of the cylinder.

In addition, the gas receiving groove may be concave in the shape of a curved surface having a radius of curvature smaller than the radius of curvature of the inner peripheral surface of the cylinder.

Alternatively, a plurality of the gas receiving grooves may be provided in the axial direction, and may be arranged to shift in a direction parallel to the axial direction.

Alternatively, the gas receiving grooves disposed in the axial direction may be disposed so as not to overlap in a direction parallel to the axial direction.

In addition, a collecting groove may be formed on an inner circumferential surface of the frame body or an outer circumferential surface of the cylinder to communicate with the gas pocket and to be concave in a radial direction to collect oil or foreign matter.

In this case, the collecting groove may be formed on an inner circumferential surface of the frame body and may extend in a circumferential direction.

In addition, a porous material may be inserted into the collection groove.

In this case, the porous material may have pores having a size capable of passing only particles having a diameter of 5 micrometers or less.

In addition, the collection groove may extend 360 degrees in the circumferential direction of the frame body, and the porous material may be provided in a ring shape in the collection groove.

A compressor according to another embodiment of the present invention includes a cylinder body having a cylindrical shape and a cylinder flange extending radially outward from the front of the cylinder body, and the piston reciprocates in the axial direction into a space formed inside the cylinder body. A cylinder moving to form a compression space for compressing the refrigerant gas; A frame body accommodating the cylinder body therein, and a frame flange extending radially outward from the front of the frame body and coupled to the cylinder flange, one side communicates with the outside to allow refrigerant gas to flow therein and the other side A frame in which a gas hole communicating with a gas pocket including a space between an inner circumferential surface of the frame body and an outer circumferential surface of the cylinder body is formed; A front sealing member interposed between the cylinder and the frame in front of the gas hole to seal the front of the gas pocket; And a rear sealing member interposed between the cylinder and the frame at the rear of the gas hole to seal the rear of the gas pocket, wherein one side of the cylinder body communicates with the gas pocket and the other side is inside the cylinder body. A gas inlet part communicating with the formed space is formed, and a collecting groove may be formed on an inner circumferential surface of the frame body or an outer circumferential surface of the cylinder body to collect oil or foreign matter by communicating with the gas pocket and concave in a radial direction.

In addition, the collecting groove may be formed on an inner circumferential surface of the frame body and may extend in a circumferential direction.

In addition, a porous material may be inserted into the collection groove.

Here, the porous material may have pores having a size capable of passing only particles having a diameter of 5 micrometers or less.

The compressor according to the present specification may prevent the oil introduced through the gas inlet from moving to the sliding part by reducing the assembly tolerance between the cylinder and the frame. This reduces the gap between the cylinder and the frame and increases the surface friction acting on the oil, thereby preventing the oil from moving within the gas inlet. With this effect, the compressor according to the present specification can improve durability and reliability by minimizing contact between the piston and the cylinder.

In addition, according to at least one of the embodiments of the present specification, it is possible to prevent the oil or foreign matter flowing into the gas inlet from being collected and moved to the sliding part.

In addition, according to at least one of the embodiments of the present specification, regardless of a mistake in the coupling process of the cylinder or a durability problem over time, the restrictor function can be maintained and contaminants or oil can be prevented from moving to the air supply port.

1 is a cross-sectional view for explaining the structure of a compressor.
2 is a cross-sectional view for explaining the coupling structure of the frame and the cylinder.
3 is a cross-sectional view showing an enlarged portion A in FIG. 2.
4 is a diagram showing a phenomenon that may occur when oil is introduced into a sliding part.
5 is a schematic diagram for explaining the behavior of oil infiltrating the gap.
6 is a perspective view showing a cylinder coupling structure of the compressor according to the first embodiment.
7 is a cross-sectional view showing an enlarged portion B in FIG. 6.
8 is a diagram for explaining a phenomenon in which oil cannot proceed into the cylinder due to friction.
9 is a cross-sectional view showing a modified embodiment of FIG. 8.
10 is a cross-sectional view showing another modified embodiment of FIG. 8.
11 is a perspective view showing a cylinder according to a comparative example.
12 is a perspective view showing a cylinder according to the second embodiment.
13 is a cross-sectional view showing a cylinder coupling structure of a compressor according to a second embodiment.
14 is a diagram showing the flow of the refrigerant in FIG. 12.
FIG. 15 is an enlarged view of portion C in FIG. 13.
16 is a graph showing a difference in flow rate when the width of the supply air passage is changed.
17 is a graph showing the difference in flow rate when the gap between the frame and the cylinder is changed.
18 is a perspective view showing a cross section of a frame to explain an air supply passage according to the second embodiment.
19 is a diagram showing various embodiments of a cross-sectional shape of an air supply passage.
20 is a perspective view showing a cylinder according to the third embodiment.
21 is a diagram illustrating various embodiments of a restrictor area.

Hereinafter, embodiments disclosed in the present specification (discloser) will be described in detail with reference to the accompanying drawings, but the same or similar elements are assigned the same reference numerals regardless of the reference numerals, and redundant descriptions thereof will be omitted. do.

In describing the embodiments disclosed in the present specification, when a component is referred to as being "connected" or "connected" to another component, it may be directly connected to or connected to the other component, It should be understood that other components may exist in the middle.

In addition, in describing the embodiments disclosed in the present specification, when it is determined that a detailed description of related known technologies may obscure the subject matter of the embodiments disclosed in the present specification, the detailed description thereof will be omitted. In addition, the accompanying drawings are for easy understanding of the embodiments disclosed in the present specification, and the technical idea disclosed in the present specification is not limited by the accompanying drawings, and all changes included in the spirit and scope of the present specification It should be understood to include equivalents or substitutes.

On the other hand, terms of the discloser may be replaced with terms such as document, specification, and description.

1 is a cross-sectional view for explaining the structure of the compressor 100.

Hereinafter, the compressor according to the present specification will be described as an example of a linear compressor that sucks and compresses a fluid while performing a linear reciprocating motion of a piston, and discharges the compressed fluid.

The linear compressor may be a component of a refrigeration cycle, and the fluid compressed in the linear compressor may be a refrigerant circulating in the refrigeration cycle. In addition to the compressor, the refrigeration cycle includes a condenser, an expansion device, and an evaporator. In addition, the linear compressor may be used as a component of a cooling system of a refrigerator, but is not limited thereto and may be widely used throughout the industry.

Referring to FIG. 1, the compressor 100 includes a casing 110 and a main body accommodated in the casing 110, and the main body includes a frame 120, a cylinder 140 fixed to the frame 120, and , And a piston 150 for linear reciprocating motion inside the cylinder 140, and a driving unit 130 that is fixed to the frame 120 and provides a driving force to the piston 150. Here, the cylinder 140 and the piston 150 may be referred to as compression units 140 and 150.

In addition, the compressor 100 may include a bearing means for reducing friction between the cylinder 140 and the piston 150. The bearing means can be oil bearings or gas bearings. Alternatively, a mechanical bearing may be used as a bearing means.

The main body of the compressor 100 may be elastically supported by support springs 116 and 117 installed at both inner ends of the casing 110. The support spring includes a first support spring 116 for supporting the rear of the main body and a second support spring 117 for supporting the front of the main body, and may be provided as a leaf spring. In addition, the support springs 116 and 117 may absorb vibrations and shocks generated by the reciprocating motion of the piston 150 while supporting the internal parts of the body.

The casing 110 may form an enclosed space, and the enclosed space includes a receiving space 101 in which the sucked refrigerant is accommodated, a suction space 102 filled with the refrigerant before being compressed, and a compression space for compressing the refrigerant. 103 and a discharge space 104 filled with the compressed refrigerant are formed.

That is, the refrigerant sucked from the suction pipe 114 connected to the rear side of the casing 110 is filled in the receiving space 101, and the refrigerant in the suction space 102 communicating with the receiving space 101 is compressed space 103 It is compressed in and discharged to the discharge space 104, and discharged to the outside through a discharge pipe 115 connected to the front side of the casing 110.

The casing 110 has a shell 111 formed in an elongated cylindrical shape with an opening at both ends thereof, a first shell cover 112 coupled to the rear side of the shell 111, and a second shell cover 112 coupled to the front side. It may be made of a shell cover (113). Here, the front side denotes a direction in which the compressed refrigerant is discharged to the left side of the drawing, and the rear side denotes a direction in which the refrigerant flows to the right side of the drawing. In addition, the first shell cover 112 or the second shell cover 113 may be integrally formed with the shell 111.

In addition, the casing 110 may be formed of a thermally conductive material. Through this, heat generated in the inner space of the casing 110 can be quickly radiated to the outside.

The first shell cover 112 is coupled to the shell 111 to seal the rear side of the shell 111, and a suction pipe 114 is inserted in the center of the first shell cover 112 to be coupled.

In addition, the rear side of the compressor body may be elastically supported in the radial direction by the first shell cover 112 through the first support spring 116.

The first support spring 116 may be provided as a circular leaf spring, the edge portion is supported by the back cover 123 in the front direction through the support bracket 123a, and the opened central portion is provided through the suction guide 116a. It may be supported by the first shell cover 112 in the rear direction.

The suction guide 116a is formed in a cylindrical shape in which a through passage is provided. The suction guide 116a may have a central opening of the first support spring 116 coupled to the front outer circumferential surface, and the rear end may be supported by the first shell cover 112. In this case, a separate suction side support member 116b may be interposed between the suction guide 116a and the inner surface of the first shell cover 112.

In addition, the rear side of the suction guide 116a communicates with the suction pipe 114, and the refrigerant sucked through the suction pipe 114 passes through the suction guide 116a and may smoothly flow into the muffler unit 160, which will be described later.

In addition, a damping member 116c made of a rubber material or the like may be installed between the suction guide 116a and the suction side support member 116b. Accordingly, it is possible to block the transmission of vibrations that may occur while the refrigerant is sucked through the suction pipe 114 to the first shell cover 112.

The second shell cover 113 may be coupled to the shell 111 to seal the front side of the shell 111, and the discharge pipe 115 may be inserted and coupled through the roof pipe 115a. The refrigerant discharged from the compression space 103 may pass through the discharge cover assembly 180 and then be discharged to the refrigeration cycle through the roof pipe 115a and the discharge pipe 115.

In addition, the front side of the compressor body may be elastically supported in the radial direction by the shell 111 or the second shell cover 113 through the second support spring 117.

The second support spring 117 may be provided as a circular leaf spring, and the opened central portion is supported by the discharge cover assembly 180 in the rear direction through the first support guide 117b, and the edge portion is supported by the support bracket 117a. ) May be supported on the inner circumferential surface of the shell 111 adjacent to the shell 111 or the second shell cover 113 in the radial direction. Alternatively, unlike the drawings, the edge portion of the second support spring 117 may be supported by the second shell cover 113 in the front direction through a bracket (not shown).

The first support guide 117b is formed in a continuous cylindrical shape with different diameters, the front side is inserted into the central opening of the second support spring 117, and the rear side is inserted into the central opening of the discharge cover assembly 180. Can be inserted. In addition, the support cover 117c may be coupled to the front side of the first support guide 117b with the second support spring 117 interposed therebetween. And the front side of the support cover (117c) is coupled with a cup-shaped second support guide (117d) that is concave forward, and the inside of the second shell cover (113) corresponds to the second support guide (117d) and is concave to the rear. The cup-shaped third support guide 117e may be coupled. The second support guide 117d may be inserted into the third support guide 117e and supported in the axial and radial directions. In this case, a gap may be formed between the second support guide 117d and the third support guide 117e.

The frame 120 includes a body portion 121 supporting the outer circumferential surface of the cylinder 140 and a flange portion 122 connected to one side of the body portion 121 and supporting the driving unit 130. In addition, the frame 120 may be elastically supported by the casing 110 by the first support spring 116 and the second support spring 117 together with the driving unit 130 and the cylinder 140.

The body portion 121 may be formed in a cylindrical shape surrounding the outer circumferential surface of the cylinder 140, and the flange portion 122 may be formed to extend in a radial direction from the front end of the body portion 121.

The cylinder 140 may be coupled to the inner circumferential surface of the body portion 121, and the inner stator 134 may be coupled to the outer circumferential surface. For example, the cylinder 140 may be fixed by press fitting to the inner circumferential surface of the body portion 121 and the inner stator 134 may be fixed using a fixing ring.

The outer stator 131 may be coupled to the rear surface of the flange portion 122, and the discharge cover assembly 180 may be coupled to the front surface. For example, the outer stator 131 and the discharge cover assembly 180 may be fixed through a mechanical coupling means.

And a bearing inlet groove (125a) forming a part of the gas bearing is formed on one side of the front surface of the flange portion (122), and a bearing communication hole (125b) penetrating from the bearing inlet groove (125a) to the inner circumferential surface of the body portion (121). Is formed, and a gas groove 125c communicating with the bearing communication hole 125b may be formed on the inner circumferential surface of the body portion 121.

The bearing inlet groove (125a) is formed by being depressed in the axial direction to a predetermined depth, and the bearing communication hole (125b) is a hole having a smaller cross-sectional area than the bearing inlet groove (125a) and is formed to be inclined toward the inner circumferential surface of the body portion (121). I can. In addition, the gas groove 125c may be formed in an annular shape having a predetermined depth and an axial length on the inner peripheral surface of the body portion 121. Alternatively, the gas groove 125c may be formed on the outer circumferential surface of the cylinder 140 where the inner circumferential surface of the body portion 121 contacts, or may be formed on both the inner circumferential surface of the body portion 121 and the outer circumferential surface of the cylinder 140.

In addition, a gas inlet 142 corresponding to the gas groove 125c may be formed on the outer circumferential surface of the cylinder 140. The gas inlet 142 forms a kind of nozzle part in the gas bearing.

Meanwhile, the frame 120 and the cylinder 140 may be made of aluminum or aluminum alloy.

The cylinder 140 is formed in a cylindrical shape in which both ends are open, the piston 150 is inserted through the rear end, and the front end may be closed through the discharge valve assembly 170. In addition, a compression space 103 surrounded by a front end (head portion, 151) of the cylinder 140 and the piston 150 and the discharge valve assembly 170 may be formed. The compression space 103 increases in volume when the piston 150 moves backward, and decreases in volume as the piston 150 advances. That is, the refrigerant introduced into the compression space 103 is compressed while the piston 150 advances, and may be discharged through the discharge valve assembly 170.

In addition, the front end of the cylinder 140 may be bent outward to form a flange portion 141. The flange portion 141 of the cylinder 140 may be coupled to the frame 120. For example, a flange groove corresponding to the flange portion 141 of the cylinder 140 may be formed at the front end of the frame 120, and the flange portion 141 of the cylinder 140 is inserted into the flange groove. It can be coupled through a mechanical coupling member.

Meanwhile, a gas bearing means capable of lubricating gas between the cylinder 140 and the piston 150 by supplying discharge gas at an interval between the outer circumferential surface of the piston 150 and the outer circumferential surface of the cylinder 140 may be provided. The discharge gas between the cylinder 140 and the piston 150 provides a levitation force to the piston 150 to reduce friction of the piston 150 against the cylinder 140.

For example, the cylinder 140 communicates with the gas groove 125c formed on the inner circumferential surface of the body portion 121, passes through the cylinder 140 in the radial direction, and stores the compressed refrigerant flowing into the gas groove 125c. A gas inlet 142 for guiding between the inner circumferential surface of the cylinder 140 and the outer circumferential surface of the piston 150 may be formed. Alternatively, in consideration of the convenience of processing, the gas groove 125c may be formed on the outer circumferential surface of the cylinder 140.

The inlet of the gas inlet 142 may be relatively wide, and the outlet may be formed as a fine hole to serve as a nozzle. A filter (not shown) may be additionally provided at the inlet of the gas inlet 142 to block the inflow of foreign substances. The filter may be a metal mesh filter, or may be formed by winding a member such as cecil.

In addition, a plurality of gas inlets 142 may be independently formed, or an inlet may be formed as an annular groove and a plurality of outlets may be formed along the annular groove at predetermined intervals.

In addition, the gas inlet 142 may be formed only on the front side with respect to the middle of the axial direction of the cylinder 140, or may be formed at the rear side in consideration of the sagging of the piston 150.

The piston 150 is inserted into the open end of the rear of the cylinder 140 and is provided to seal the rear of the compression space 103.

The piston 150 includes a head portion 151 that divides the compression space 103 in a disk shape and a cylindrical guide portion 152 that extends rearward from the outer circumferential surface of the head portion 151. The head part 151 is provided to be partially open, the guide part 152 is empty inside, and the front part is partially sealed by the head part 151, but the rear part is opened so that it is connected to the muffler unit 160. It is prepared. In addition, the head portion 151 may be provided as a separate member coupled to the guide portion 152, or the head portion 151 and the guide portion 152 may be integrally formed.

In addition, a suction port 154 is formed through the head 151 of the piston 150. The suction port 154 is provided to communicate the suction space 102 and the compression space 103 inside the piston 150. For example, the refrigerant flowing from the receiving space 101 to the suction space 102 inside the piston 150 passes through the suction port 154 and passes through the compression space 103 between the piston 150 and the cylinder 140. ) Can be inhaled.

The suction port 154 may extend in the axial direction of the piston 150. Alternatively, the suction port 154 may be formed to be inclined in the axial direction of the piston 150. For example, the suction port 154 may extend to be inclined toward the rear of the piston 150 in a direction away from the central axis.

In addition, the suction port 154 may have a circular opening and a constant inner diameter. Alternatively, the suction port 154 may be formed as a long hole whose opening extends in the radial direction of the head portion 151, and may be formed such that the inner diameter increases toward the rear.

In addition, a plurality of suction ports 154 may be formed in one or more of a radial direction and a circumferential direction of the head unit 151.

In addition, a suction valve 155 for selectively opening and closing the suction port 154 may be mounted on the head 151 of the piston 150 adjacent to the compression space 103. The suction valve 155 may be operated by elastic deformation to open or close the suction port 154. That is, the suction valve 155 may be elastically deformed to open the suction port 154 by the pressure of the refrigerant flowing through the suction port 154 to the compression space 103.

In addition, the piston 150 is connected to the mover 135, and the mover 135 reciprocates in the front-rear direction according to the movement of the piston 150. An inner stator 134 and a cylinder 140 may be positioned between the mover 135 and the piston 150. In addition, the mover 135 and the piston 150 may be connected to each other by a magnet frame 136 formed by bypassing the cylinder 140 and the inner stator 134 to the rear.

The muffler unit 160 is coupled to the rear of the piston 150 and is provided to attenuate noise generated during the process of inhaling the refrigerant into the piston 150. The refrigerant sucked through the suction pipe 114 flows into the suction space 102 inside the piston 150 through the muffler unit 160.

The muffler unit 160 includes a suction muffler 161 communicating with the receiving space 101 of the casing 110, and an inner guide 162 connected to the front of the suction muffler 161 and guiding the refrigerant to the suction port 154. ).

The suction muffler 161 is located at the rear of the piston 142, the rear opening is disposed adjacent to the suction pipe 114, and the front end may be coupled to the rear of the piston 142. The suction muffler 161 may have a flow path formed in the axial direction to guide the refrigerant in the receiving space 101 to the suction space 102 inside the piston 150.

In this case, a plurality of noise spaces partitioned by baffles may be formed inside the suction muffler 161. The suction muffler 161 may be formed by two or more members being coupled to each other. For example, a second suction muffler may be press-fitted into the first suction muffler to form a plurality of noise spaces. In addition, the suction muffler 161 may be formed of a plastic material in consideration of weight or insulation.

The inner guide 162 may have a pipe shape in which one side communicates with the noise space of the suction muffler 161 and the other side is deeply inserted into the piston 142. The inner guide 162 may be formed in a cylindrical shape in which both ends are provided with the same inner diameter, but in some cases, the inner diameter of the front end, which is the discharge side, may be formed larger than the inner diameter of the rear end, which is the opposite side.

The suction muffler 161 and the inner guide 162 may be provided in various shapes, through which the pressure of the refrigerant passing through the muffler unit 160 can be adjusted. In addition, the suction muffler 161 and the inner guide 162 may be integrally formed.

The discharge valve assembly 170 may include a discharge valve 171 and a valve spring 172 provided at a front side of the discharge valve 171 to elastically support the discharge valve 171. The discharge valve assembly 170 may selectively discharge the refrigerant compressed in the compression space 103. Here, the compression space 103 may be understood as a space formed between the suction valve 155 and the discharge valve 171.

The discharge valve 171 is disposed to be supported on the front surface of the cylinder 140 and may be mounted to selectively open and close the front opening of the cylinder 140. The discharge valve 171 may be operated by elastic deformation to open or close the compression space 103. The discharge valve 171 may be elastically deformed to open the compression space 103 by the pressure of the refrigerant flowing into the discharge space 104 through the compression space 103. For example, in a state in which the discharge valve 171 is supported on the front surface of the cylinder 140, the compression space 103 is maintained in a closed state, and the discharge valve 171 is spaced apart from the front surface of the cylinder 140. The compressed refrigerant in the compressed space 103 may be discharged from the space opened in FIG.

The valve spring 172 is provided between the discharge valve 171 and the discharge cover assembly 180 to provide an elastic force in the axial direction. The valve spring 172 may be provided as a compression coil spring, or may be provided as a leaf spring in consideration of an occupied space or reliability aspect.

When the pressure in the compression space 103 is greater than or equal to the discharge pressure, the valve spring 172 deforms forward to open the discharge valve 171, and the refrigerant is discharged from the compression space 103 to prevent the discharge cover assembly 180. It is discharged to the first discharge space 103a. And when the discharge of the refrigerant is completed, the valve spring 172 provides a restoring force to the discharge valve 171 so that the discharge valve 171 is closed.

A process in which the refrigerant flows into the compression space 103 through the suction valve 155 and the refrigerant in the compression space 103 through the discharge valve 171 is discharged to the discharge space 104 will be described as follows.

In the course of the piston 150 reciprocating and linear movement inside the cylinder 140, when the pressure in the compression space 103 becomes less than a predetermined suction pressure, the suction valve 155 is opened and the refrigerant is transferred to the compression space 103. Inhaled. On the other hand, when the pressure in the compression space 103 exceeds a predetermined suction pressure, the refrigerant in the compression space 103 is compressed while the suction valve 155 is closed.

On the other hand, when the pressure in the compression space 103 reaches a predetermined discharge pressure or more, the valve spring 172 deforms forward and opens the discharge valve 171 connected thereto, and the refrigerant is transferred from the compression space 103 to the discharge cover assembly ( It is discharged to the discharge space 104 of 180). When the discharge of the refrigerant is completed, the valve spring 172 provides a restoring force to the discharge valve 171 and the discharge valve 171 is closed to seal the front of the compression space 103.

The discharge cover assembly 180 is installed in front of the compression space 103 to form a discharge space 104 to receive the refrigerant discharged from the compression space 103, and is coupled to the front of the frame 120 to allow the refrigerant to be Noise generated in the process of being discharged from the compression space 103 may be attenuated. The discharge cover assembly 180 may be coupled to the front of the flange portion 122 of the frame 120 while accommodating the discharge valve assembly 170. For example, the discharge cover assembly 180 may be coupled to the flange portion 122 through a mechanical coupling member.

In addition, between the discharge cover assembly 180 and the frame 120, a gasket 165 for heat insulation and an O-ring 166 for suppressing leakage of the refrigerant in the discharge space 104 may be provided.

The discharge cover assembly 180 may be formed of a thermally conductive material. Therefore, when a high-temperature refrigerant flows into the discharge cover assembly 180, heat of the refrigerant may be transferred to the casing 110 through the discharge cover assembly 180 to radiate heat to the outside of the compressor.

The discharge cover assembly 180 may be formed of one discharge cover, or may be arranged so that a plurality of discharge covers are sequentially communicated. When a plurality of discharge covers are provided, the discharge space 104 may include a plurality of spaces partitioned by each discharge cover. The plurality of space portions are arranged in the front-rear direction and communicate with each other.

For example, when there are three discharge covers, the discharge space 104 is a first discharge space 103a formed between the first discharge cover 181 and the frame 120 coupled to the front side of the frame 120 And, a second discharge space 103b formed between the second discharge cover 182 and the first discharge cover 181 communicating with the first discharge space 103a and coupled to the front side of the first discharge cover 181 ), and a third discharge space formed between the third discharge cover 183 and the second discharge cover 182 communicated with the second discharge space 103b and coupled to the front side of the second discharge cover 182 ( 103c).

And the first discharge space (103a) is selectively communicated with the compression space (103) by the discharge valve (171), the second discharge space (103b) is communicated with the first discharge space (103a), the third discharge space (103c) may communicate with the second discharge space (103b). Accordingly, the refrigerant discharged from the compression space 103 passes through the first discharge space 103a, the second discharge space 103b, and the third discharge space 103c in order to reduce the discharge noise, and the third discharge It may be discharged to the outside of the casing 110 through the roof pipe 115a and the discharge pipe 115 communicated with the cover 183.

The driving unit 130 includes an outer stator 131 disposed between the shell 111 and the frame 120 to surround the body portion 121 of the frame 120, and between the outer stator 131 and the cylinder 140 It may include an inner stator 134 disposed to surround the cylinder 140 and a mover 135 disposed between the outer stator 131 and the inner stator 134.

The outer stator 131 may be coupled to the rear of the flange portion 122 of the frame 120, and the inner stator 134 may be coupled to the outer peripheral surface of the body portion 121 of the frame 120. In addition, the inner stator 134 may be disposed to be spaced apart from the inner stator 131, and the mover 135 may be disposed in a space between the outer stator 131 and the inner stator 134.

The outer stator 131 may be equipped with a winding coil, and the mover 135 may have a permanent magnet. The permanent magnet may be composed of a single magnet having one pole, or may be composed of a combination of a plurality of magnets having three poles.

The outer stator 131 includes a coil winding body 132 surrounding the axial direction in a circumferential direction and a stator core 133 stacked while surrounding the coil winding body 132. The coil winding body 132 may include a hollow cylindrical bobbin 132a and a coil 132b wound in the circumferential direction of the bobbin 132a. The cross section of the coil 132b may be formed in a circular or polygonal shape, and for example, may have a hexagonal shape. In addition, in the stator core 133, a plurality of lamination sheets may be radially stacked, or a plurality of lamination blocks may be stacked along a circumferential direction.

In addition, the front side of the outer stator 131 may be supported by the flange portion 122 of the frame 120, and the rear side may be supported by the stator cover 137. For example, the stator cover 137 may be provided in a hollow disk shape, the outer stator 131 may be supported on the front surface, and the resonance spring 190 may be supported on the rear surface.

The inner stator 134 may be configured by stacking a plurality of laminations on the outer circumferential surface of the body portion 121 of the frame 120 in the circumferential direction.

One side of the mover 135 may be coupled to and supported by the magnet frame 136. The magnet frame 136 has a substantially cylindrical shape and is disposed to be inserted into a space between the outer stator 131 and the inner stator 134. In addition, the magnet frame 136 is coupled to the rear side of the piston 150 and is provided to move together with the piston 150.

For example, the rear end of the magnet frame 136 is bent and extended radially inward to form a coupling portion 136a, and the coupling portion 136a is on the flange portion 153 formed at the rear of the piston 150 Can be combined. The coupling portion 136a of the magnet frame 136 and the flange portion 153 of the piston 150 may be coupled through a mechanical coupling member.

Further, a flange portion 161a formed in front of the suction muffler 161 may be interposed between the flange portion 153 of the piston 150 and the coupling portion 136a of the magnet frame 136. Therefore, the piston 150, the muffler unit 160, and the mover 135 can be linearly reciprocated together in a state in which they are integrally coupled.

When current is applied to the driving unit 130, a magnetic flux is formed in the winding coil, and the magnetic flux formed in the winding coil of the outer stator 131 and the magnetic flux formed by the permanent magnet of the mover 135 are mutually Electromagnetic force is generated by the action so that the mover 135 may move. In addition, the piston 150 connected to the magnet frame 136 is also reciprocated in the axial direction integrally with the mover 135 at the same time as the mover 135 reciprocates in the axial direction.

Meanwhile, the driving unit 130 and the compression units 140 and 150 may be supported in the axial direction by the support springs 116 and 117 and the resonance spring 190.

The resonant spring 118 amplifies the vibration implemented by the reciprocating motion of the mover 135 and the piston 150, thereby effectively compressing the refrigerant. Specifically, the resonant spring 118 may be adjusted to a frequency corresponding to the natural frequency of the piston 150 so that the piston 150 can perform resonant motion. In addition, the resonance spring 118 may cause a stable movement of the piston 150 to reduce vibration and noise generation.

The resonance spring 118 may be a coil spring extending in the axial direction. Both ends of the resonance spring 118 may be connected to the vibrating body and the fixture, respectively. For example, one end of the resonance spring 118 may be connected to the magnet frame 136 and the other end may be connected to the back cover 123. Accordingly, the resonance spring 118 may be elastically deformed between the vibrating body vibrating at one end and the fixture fixed to the other end.

The natural frequency of the resonance spring 118 is designed to match the resonance frequency of the mover 135 and the piston 150 when the compressor 100 is operated, so that the reciprocating motion of the piston 150 may be amplified. However, since the back cover 123 provided as a fixture is elastically supported by the casing 110 through the first support spring 116, it may not be strictly fixed.

The resonance spring 118 may include a first resonance spring 118a supported on the rear side based on the spring supporter 119 and a second resonance spring 118b supported on the front side.

The spring supporter 119 includes a body portion 119a surrounding the suction muffler 161, a coupling portion 119b bent in an inner radial direction from the front of the body portion 119a, and at the rear of the body portion 119a. A support part 119c that is bent in an outer radial direction may be provided.

The front surface of the coupling portion 119b of the spring supporter 119 may be supported by the coupling portion 136a of the magnet frame 136. In addition, the inner diameter of the coupling portion 119b of the spring supporter 119 may be provided to surround the outer diameter of the suction muffler 161. For example, the coupling portion 119b of the spring supporter 119, the coupling portion 136a of the magnet frame 136, and the flange portion 153 of the piston 150 are sequentially arranged and then integrated through a mechanical member. Can be combined with At this time, as described above, the flange portion 161a of the suction muffler 161 may be interposed between the flange portion 153 of the piston 150 and the coupling portion 136a of the magnet frame 136 to be fixed together. same.

The first resonance spring 118a may be provided between the front surface of the back cover 123 and the rear surface of the spring supporter 119, and the second resonance spring 118b is the rear surface and the spring of the stator cover 137 It may be provided between the front surface of the supporter 119.

In addition, a plurality of first and second resonance springs 118a and 118b may be disposed in the circumferential direction of the central axis. In addition, the first resonance spring 118a and the second resonance spring 118b may be disposed parallel to each other in the axial direction, or may be disposed alternately with each other. In addition, the first and second springs 118a and 118b may be disposed at regular intervals in the radial direction of the central axis. For example, three first and second springs 118a and 118b may be provided, respectively, and may be disposed at intervals of 120 degrees in the radial direction of the central axis.

On the other hand, the compressor 100 may include a plurality of sealing members capable of increasing the coupling force between the frame 120 and the surrounding parts.

For example, a plurality of sealing members may include a discharge cover sealing member interposed in a portion where the frame 120 and the discharge cover assembly 180 are coupled and inserted into an installation groove provided at the front end of the frame 120, and the frame ( 120) and the cylinder 140 may include a cylinder sealing member that is provided at the coupling portion and inserted into the installation groove provided on the outer surface of the cylinder 140. The cylinder sealing member prevents the refrigerant in the gas groove 125c formed between the inner circumferential surface of the frame 120 and the outer circumferential surface of the cylinder 140 from leaking to the outside, and increases the coupling force between the frame 120 and the cylinder 140 I can make it. In addition, the plurality of sealing members may further include an inner stator sealing member provided at a portion where the frame 120 and the inner stator 134 are coupled and inserted into an installation groove provided on an outer surface of the frame 120. The sealing members may have a ring shape.

The operation of the linear compressor 100 described above is as follows.

First, when a current is applied to the driving unit 130, a magnetic flux may be formed in the outer stator 131 by the current flowing through the coil 132b. The magnetic flux formed in the outer stator 131 generates an electromagnetic force, and the mover 135 having a permanent magnet may linearly reciprocate by the generated electromagnetic force. Such electromagnetic force is generated in a direction (forward direction) toward the top dead center (TDC) of the piston 150 during the compression stroke, and the piston 150 is at the bottom dead center (BDC) during the suction stroke. It can occur alternately in the direction toward (rear). That is, the driving unit 130 may generate thrust, which is a force that pushes the mover 135 and the piston 150 in the moving direction.

The piston 150 linearly reciprocating within the cylinder 140 may increase and decrease the volume of the compression space 103 repeatedly.

When the piston 150 moves in the direction of increasing the volume of the compression space 103 (rear direction), the pressure in the compression space 103 decreases. Accordingly, the suction valve 155 mounted in front of the piston 150 is opened, and the refrigerant remaining in the suction space 102 can be sucked into the compression space 103 along the suction port 154. This suction stroke proceeds until the piston 150 increases the volume of the compression space 103 to the maximum and is located at the bottom dead center.

The piston 150 that has reached the bottom dead center performs a compression stroke while moving in a direction (forward direction) in which the movement direction is changed and the volume of the compression space 103 is reduced. During the compression stroke, as the pressure in the compression space 103 increases, the sucked refrigerant is compressed. When the pressure in the compression space 103 reaches the set pressure, the discharge valve 171 is pushed by the pressure in the compression space 103 and is opened from the cylinder 140, and the refrigerant is discharged through the spaced space. ) Is discharged. This compression stroke continues while the piston 150 moves to the top dead center where the volume of the compression space 103 is minimum.

As the suction stroke and the compression stroke of the piston 150 are repeated, the refrigerant flowing into the receiving space 101 inside the compressor 100 through the suction pipe 114 is a suction guide 116a, a suction muffler 161 and an inner guide ( 162, the refrigerant is introduced into the suction space 102 inside the piston 150, and the refrigerant in the suction space 102 goes to the compression space 103 inside the cylinder 140 during the suction stroke of the piston 150. Flow in. And after the refrigerant in the compression space 103 is compressed and discharged to the discharge space 104 during the compression stroke of the piston 150, it is passed through the loop pipe 115a and the discharge pipe 115 to the outside of the compressor 100. A discharged flow can be formed.

FIG. 2 is a cross-sectional view illustrating a coupling structure between the frame 220 and the cylinder 240, and FIG. 3 is an enlarged cross-sectional view of portion A in FIG. 2.

2 and 3, the cylinder 240 according to the embodiment of the present specification may be coupled to the frame 220. For example, the cylinder 240 may be disposed to be inserted into the frame 220.

The frame 220 includes a frame body 221 extending in the axial direction and a frame flange 222 extending radially outward from the frame body 221. In other words, the frame flange 222 may extend from the outer circumferential surface of the frame body 221 to form a first set angle. For example, the first set angle may be formed to about 90 degrees.

The frame body 221 has a cylindrical shape having a central axis in the axial direction, and has a body accommodating portion for accommodating the cylinder body 241 therein. In addition, a third installation groove 221a into which a third sealing member 252 disposed between the inner stator (see 134 of FIG. 1) is inserted may be formed in the rear portion of the frame body 221.

In the frame flange 222, a first wall 225a having a ring shape and coupled to the cylinder flange 242, and a second wall 225b disposed to surround the first wall 225a and having a ring shape. And a third wall 225c connecting the rear end of the first wall 225a and the rear end of the second wall 225b. The first wall 225a and the second wall 225b may extend in an axial direction, and the third wall 225c may extend in a radial direction.

A frame space part 225d defined by the first to third walls 225a, 225b, and 225c is defined. The frame space part 225d is recessed from the front end of the frame flange 222 toward the rear, and forms a part of a discharge passage through which the refrigerant discharged through the discharge valve (see 171 in FIG. 1) flows. .

In the inner space of the first wall 225a, at least a portion of the cylinder 240, for example, a flange receiving portion 221b into which the cylinder flange 242 is inserted is included. For example, the inner diameter of the flange receiving portion 221b may be formed equal to or slightly smaller than the outer diameter of the cylinder flange 242.

When the cylinder 240 is pressed into the inside of the frame 220, the cylinder flange 242 may interfere with the first wall 225a, and in this process, the cylinder flange 242 may be deformed. I can.

Further, the frame flange 222 further includes a sealing member seating portion 226 extending radially inward from the rear end of the first wall 225a. A first installation groove 226a into which the first sealing member 250 is inserted is formed in the sealing member seating portion 226. The first installation groove 226a may be configured to be recessed rearward from the sealing member seating portion 226.

The frame flange 222 further includes a fastening hole 229a to which a predetermined fastening member is coupled for fastening the frame 220 and peripheral components. A plurality of fastening holes 229a may be disposed along the outer periphery of the second wall 225a, respectively.

The frame flange 222 is formed with a terminal insertion portion 229b that provides a lead-out path of the terminal portion of the driving unit (see 130 in FIG. 1). The terminal insertion portion 229b is formed such that the frame flange 222 is cut in the front-rear direction.

The terminal portion may extend forward from the coil (see 132b of FIG. 1) and may be inserted into the terminal insertion portion 229b. With this configuration, the terminal portion may be exposed to the outside from the driving unit 130 and the frame 220 to be connected to the cable.

A plurality of terminal insertion portions 229b may be provided, and the plurality of terminal insertion portions 229b may be disposed along the outer periphery of the second wall 225b. Of the plurality of terminal insertion portions 229b, only one terminal insertion portion 229b into which the terminal portion is inserted is provided. The remaining terminal insertion portions 229b may be understood to be provided to prevent deformation of the frame 220.

For example, in the frame flange 222, three terminal insertion portions 229b are formed. Among them, the terminal portion may be inserted into one terminal insertion portion 229b, and the terminal portion may not be inserted into the other two terminal insertion portions 229b.

In the frame 220, in the process of being fastened to the stator cover (see 137 in FIG. 1) or the discharge cover assembly (see 180 in FIG. 1) or being press-fitted with the cylinder 240, a large amount of stress may be applied. have. If only one terminal insertion portion 229b is formed in the frame flange 222, the stress may be concentrated at a specific point and deformation may occur in the frame flange 222. Accordingly, in this embodiment, the terminal insertion portion 229b is formed at three places of the frame flange 222, that is, by being evenly arranged in the circumferential direction with respect to the center of the frame 220, the stress Can be prevented from occurring.

The frame 220 further includes a frame inclined portion 223 extending obliquely toward the frame body 221 from the frame flange 222. The outer surface of the frame inclined portion 223 may extend to form a second set angle with respect to the outer peripheral surface of the frame body 221, that is, an axial direction. For example, the second set angle may be formed with an angle value greater than 0 degrees and less than 90 degrees.

A gas hole 224 for guiding the refrigerant discharged from the discharge valve (see 171 in FIG. 1) to the gas inlet 232 of the cylinder 240 is formed in the frame inclined part 223. The gas hole 224 may be formed through the inside of the frame inclined portion 223.

Specifically, the gas hole 224 may extend from the frame flange 222 and may extend to the frame body 221 via the frame inclined portion 223.

Since the gas hole 224 is formed through a portion of the frame 220 having a rather thick thickness to the frame flange 222, the frame inclined portion 223 and the frame body 221, the gas hole 224 By forming, it is possible to prevent the strength of the frame 220 from being weakened.

The extending direction of the gas hole 224 may correspond to the extending direction of the frame inclined portion 223 to form the second set angle with respect to the inner circumferential surface of the frame body 221, that is, an axial direction.

A discharge filter 230 for filtering foreign substances among refrigerants to be introduced into the gas hole 224 may be disposed at an inlet portion of the gas hole 224. The discharge filter 230 may be installed on the third wall 225c.

In detail, the discharge filter 230 is installed in the filter groove 227 formed in the frame flange 222. The filter groove 227 is configured to be recessed rearward from the third wall 225c, and may have a shape corresponding to the shape of the discharge filter 230.

In other words, the inlet portion of the gas hole 224 is connected to the filter groove 227, the gas hole 224 is the frame flange 222 and the frame inclined portion 223 from the filter groove 227 It may penetrate through and extend to the inner circumferential surface of the frame body 221. Accordingly, the outlet portion of the gas hole 224 may communicate with the inner circumferential surface of the frame body 221.

In addition, a guide groove 225e for facilitating processing of the gas hole 224 may be formed in the frame flange 222. The guide groove 225e is formed such that at least a portion of the second wall 225b is recessed, and may be located at an edge of the filter groove 227.

In the process of processing the gas hole 224, the processing mechanism may be drilled from the filter groove 227 toward the frame inclined portion 223. At this time, the machining mechanism interferes with the second wall 225b, and thus, there may be a problem that the drilling is not easy. Accordingly, in this embodiment, a guide groove 225e is formed in the second wall 225b, and the processing mechanism is positioned in the guide groove 225e to facilitate processing of the gas hole 224. .

The linear compressor 10 further includes a filter sealing member 228 installed at the rear of the discharge filter 230, that is, at the outlet side. The filter sealing member 228 may have an approximately ring shape. Specifically, the filter sealing member 228 is placed in the filter groove 227, and while the discharge filter 230 presses the filter groove 227, it may be press-fit into the filter groove 227. .

Meanwhile, a plurality of the frame inclined portions 223 may be provided along the circumference of the frame body 221. Of the plurality of frame inclined portions 223, only one frame inclined portion 223 in which the gas hole 224 is formed is provided. The remaining frame inclined portion 223 may be understood to be provided to prevent deformation of the frame 220.

In the process of being fastened to the stator cover 149 or the discharge cover 160 or being press-fitted with the cylinder 240, a large amount of stress may be applied to the frame 220. If only one frame inclined portion 223 is formed in the frame 220, the stress may be concentrated at a specific point and deformation may occur in the frame 220. Accordingly, in the present embodiment, the frame inclined portion 223 is formed at three locations outside the frame body 221, that is, the frame 220 is evenly disposed in the circumferential direction with respect to the center of the frame 220, It is possible to prevent stress concentration from occurring.

The cylinder 240 is coupled to the inside of the frame 220. For example, the cylinder 240 may be coupled to the frame 220 by a press-fitting process.

The cylinder 240 includes a cylinder body 241 extending in the axial direction and a cylinder flange 242 provided outside a front portion of the cylinder body 241. The cylinder body 241 has a cylindrical shape having a central axis in the axial direction, and is inserted into the frame body 221. Accordingly, the outer circumferential surface of the cylinder body 241 may be positioned to face the inner circumferential surface of the frame main body 221.

A gas inlet 232 through which the gas refrigerant flowing through the gas hole 224 is introduced is formed in the cylinder body 241.

The linear compressor 200 further includes a gas pocket 231 formed between the inner circumferential surface of the frame 220 and the outer circumferential surface of the cylinder 240 and through which gas for a lubrication function flows. The refrigerant gas flow path from the outlet of the gas hole 224 to the gas inlet 232 forms at least a portion of the gas pocket 231. In addition, the gas inlet 232 may be disposed on the inlet side of the nozzle unit 233 to be described later.

Specifically, the gas inlet 232 may be configured to be recessed radially inward from the outer peripheral surface of the cylinder body 241. In addition, the gas inlet 232 may be configured to have a circular shape along the outer circumferential surface of the cylinder body 241 with respect to the central axis in the axial direction.

A plurality of gas inlet portions 232 may be provided. For example, two gas inlet portions 232 may be provided. Among the two gas inlet portions 232, the first gas inlet portion 232a is disposed at a position close to the front portion of the cylinder body 241, that is, a discharge valve (see 171 in FIG. 1), and the second gas The inlet portion 232b is disposed at the rear portion of the cylinder body 241, that is, at a position close to the compressor suction side of the refrigerant. In other words, the first gas inlet 232a may be positioned at a front side with respect to the center of the cylinder body 241 in the front-rear direction, and the second gas inlet 232b may be positioned at a rear side.

In addition, the first nozzle part 233a connected to the first gas inlet 232a is located on the front side with respect to the center, and the second nozzle part 233b is connected to the second gas inlet 232b. ) May be located at the rear side with respect to the center.

Specifically, the first gas inlet portion 232a or the first nozzle portion 233a is formed at a position spaced apart from the front end portion of the cylinder body 241 by a first distance. In addition, the second gas inlet portion 232b or the second nozzle portion 233b is formed at a position spaced apart from the front end of the cylinder body 241 by a second distance. The second distance may have a value greater than the first distance. In addition, a third distance from the front end of the cylinder body 241 to the center may be larger than the first distance and smaller than the second distance.

In addition, the fourth distance from the center to the first gas inlet 232a or the first nozzle part 233a is from the center to the second gas inlet 232b or the second nozzle part 233b. It may be determined to be a value smaller than the fifth distance.

Meanwhile, the first gas inlet 232a is formed at a position adjacent to the outlet of the gas hole 224. In other words, a distance from the outlet of the gas hole 224 to the first gas inlet 232a may be smaller than a distance from the outlet to the second gas inlet 232b. For example, the outlet portion of the gas hole 224 and the first gas inlet portion 232a may be disposed to partially overlap each other.

Since the internal pressure of the cylinder 240 is formed relatively high at a position close to the discharge side of the refrigerant, that is, inside the first gas inlet 232a, the outlet of the gas hole 224 is the first gas inlet By being positioned adjacent to 232a, a relatively large amount of refrigerant can be introduced into the cylinder 240 through the first gas inlet 232a. As a result, by enhancing the function of the gas bearing, it is possible to prevent wear of the cylinder 240 and the piston 150 during the reciprocating movement of the piston 150.

A cylinder filter member 232c may be installed in the gas inlet 232. The cylinder filter member 232c blocks foreign substances of a predetermined size or more from flowing into the cylinder 240 and absorbs oil contained in the refrigerant. Here, the predetermined size may be 1 μm.

The cylinder filter member 232c includes a thread wound around the gas inlet 232. In detail, the thread is made of polyethylene terephthalate (PET) material and may have a predetermined thickness or diameter.

The thickness or diameter of the thread may be determined to be an appropriate value in consideration of the strength of the thread. If the thickness or diameter of the thread is too small, the strength of the thread becomes too weak and can be easily broken. If the thickness or diameter of the thread is too large, the thread is wound. In this case, there is a problem in that the air gap in the gas inlet 232 becomes too large to reduce the filtering effect of foreign matter.

The cylinder body 241 includes a nozzle part 233 extending radially inward from the gas inlet 232. The nozzle part 233 may extend to an inner circumferential surface of the cylinder body 241.

The radial length of the nozzle part 233 is formed to be smaller than the radial length of the gas inlet part 232, that is, a recessed depth. In addition, the size of the inner space of the nozzle part 233 may be smaller than the size of the inner space of the gas inlet part 232.

Specifically, the depressed depth and width of the gas inlet 232 and the length of the nozzle part 233 are the stiffness of the cylinder 240, the amount of the cylinder filter member 232c, or the nozzle part. An appropriate size may be determined in consideration of the size of the pressure drop of the refrigerant passing through 233.

For example, when the depth and width of the gas inlet 232 are too large or the length of the nozzle 233 is too small, the stiffness of the cylinder 240 may be weakened. On the other hand, if the depth and width of the gas inlet 232 are too small, the amount of the cylinder filter member 232c that can be installed in the gas inlet 232 may be too small. In addition, when the length of the nozzle part 233 is too large, the pressure drop of the refrigerant passing through the nozzle part 233 becomes too large, so that a sufficient function as a gas bearing cannot be performed.

In this embodiment, a ratio of the length of the nozzle portion 233 to the length of the gas inlet portion 232 is proposed in the range of 0.65 or more and 0.75. Within the range of the ratio, the effect of the gas bearing is improved and the rigidity of the cylinder 240 can be maintained at a required level.

In addition, the diameter of the inlet portion of the nozzle portion 233 may be larger than the diameter of the outlet portion. Based on the flow direction of the refrigerant, the cross-sectional area of the flow in the nozzle part 233 is gradually reduced from the inlet to the outlet. Here, the inlet portion is a portion connected to the gas inlet portion 232 to introduce the refrigerant into the nozzle portion 233, and the outlet portion is connected to the inner peripheral surface of the cylinder 240 to the outer peripheral surface of the piston 150 It can be understood as a part that supplies a refrigerant.

Specifically, when the diameter of the nozzle part 233 is too large, the amount of the refrigerant flowing into the nozzle part 233 among the high-pressure gas refrigerant discharged through the discharge valve 161 becomes too large, and the compressor There is a problem that the flow loss becomes large. On the other hand, if the diameter of the nozzle part 233 is too small, the pressure drop in the nozzle part 233 increases, and there is a problem that the performance as a gas bearing decreases.

Accordingly, in the present embodiment, the diameter of the inlet portion of the nozzle portion 233 is formed relatively large to reduce the pressure drop of the refrigerant flowing into the nozzle portion 233, and the diameter of the outlet portion is formed relatively small. The inflow amount of the gas bearing through the unit 233 may be adjusted to a predetermined value or less.

For example, in this embodiment, the ratio of the diameter of the inlet part to the diameter of the outlet part of the nozzle part 233 is determined to be a value of 4 or more and 5 or less. Within the range of this ratio, it can be expected to improve the effect of the gas bearing.

The nozzle part 233 includes a first nozzle part 233a extending from the first gas inlet part 232a to an inner circumferential surface of the cylinder body 241 and the cylinder body from the second gas inlet part 232b. A second nozzle part 233b extending to the inner circumferential surface of 241 is included.

The refrigerant filtered by the cylinder filter member 232c while passing through the first gas inlet part 232a is passed through the first nozzle part 233a to the inner circumferential surface of the cylinder body 241 and the piston body 150 ) Flows into the space between the outer circumferential surfaces. And the refrigerant filtered by the cylinder filter member 232c while passing through the second gas inlet 232b is passed through the second nozzle unit 233b to the inner circumferential surface of the cylinder body 241 and the piston body ( 150) flows into the space between the outer circumferential surfaces.

The gas refrigerant flowing toward the outer circumferential surface of the piston body 150 through the first and second nozzle portions 233a and 233b provides a levitation force to the piston 150, thereby providing a gas bearing for the piston 150. Performs the function of.

Since the first sealing member 250 seals the space on the front side of the gas pocket 231, the refrigerant flowing through the gas pocket 231 is prevented from leaking to the front side of the frame 220 and the cylinder 240. Can be prevented. And since the second sealing member 251 seals the space on the rear side of the gas pocket 231, the refrigerant flowing through the gas pocket 231 leaks to the rear side of the frame 220 and the cylinder 240. Can be prevented. Thus, the performance of the gas bearing can be improved.

In addition, a second installation groove 241a into which a third sealing member 252 disposed between the flange body 221 is inserted may be formed at a rear portion of the cylinder body 241.

In the case of the embodiment of the present specification, gas bearing means may be used as described above. The gas bearing means may provide gas lubrication between the cylinder 240 and the piston 150 by supplying discharge gas at an interval between the outer circumferential surface of the piston 150 and the outer circumferential surface of the cylinder 240. The discharge gas between the cylinder 240 and the piston 150 provides a levitation force to the piston 150 to reduce friction of the piston 150 against the cylinder 240.

Hereinafter, a space between the cylinder 240 and the piston 150, that is, a space filled with the discharge gas supplied to provide a levitation force, will be referred to as a sliding part.

FIG. 4 is a diagram showing a phenomenon that may occur when oil is introduced into a sliding part, and FIG. 5 is a schematic diagram for explaining the behavior of oil penetrating into a gap.

If oil flows into the sliding part, the lubricating performance of the discharged gas may decrease rapidly. This is because the introduced oil generates a high dynamic pressure in the sliding part and acts as an airbag, so that the piston 150 can be pushed to one side to cause contact with the inner wall of the cylinder 240. This may cause wear and tear of the piston 150.

In this way, a plurality of sealing members are installed in the coupling structure to prevent oil from flowing into the sliding part. However, in order to use the gas bearing means, a gas inlet 232 for introducing a refrigerant gas into the sliding portion is required, and oil inflow through the gas inlet 232 must be blocked.

The gas inlet 232 is equipped with a discharge filter 230 for blocking foreign substances, but due to the limitation of the discharge filter 230 specifications, it is difficult to filter the oil dissolved in the refrigerant. This is because the refrigerant is sucked in a gaseous state through the suction pipe, but the refrigerant may be phase-transformed into a liquid state in a part of the compressor 200 at high pressure and low temperature, and the surrounding oil may be dissolved in the phase-shifted refrigerant. . For example, even if the highest-spec discharge filter 230 is mounted, the oil dissolved in the r600a refrigerant cannot be filtered out.

The oil dissolved in the refrigerant may generate an oil lump between the frame 220 and the cylinder 240, and the generated oil may flow into the sliding part, causing a problem. For reference, since oil has a very small surface tension than water, when the oil touches a solid surface, the contact angle is very small, so that it can easily pass through a relatively narrow gap.

Referring to FIG. 4A, when oil (o) is generated in the lower part of the sliding part, the oil (o) acts as an airbag during the compression stroke of the piston 150, so that the front of the piston 150 is moved upward. A lifting force is generated, and the front upper portion of the piston 150 comes into contact with the front upper portion of the inner wall of the cylinder 240.

Referring to (b) of FIG. 4, when oil (o) is generated in the upper part of the sliding part, the oil (o) acts as an airbag during the suction stroke of the piston 150 to move the rear of the piston 150 downward. A force to be pushed is generated, and the rear lower portion of the piston 150 comes into contact with the rear lower portion of the inner wall of the cylinder 240.

Referring to FIG. 5, it can be seen that when the oil (o) is mixed with the moisture (w), the oil (o) may penetrate into a narrow gap. This is possible because oil (o) has a very small surface tension than water (w). Fine oil droplets (o) gather and grow around the narrow gap, and oil droplets (o) with a small surface tension are sucked into the narrow gap due to the pressure difference. The penetrated oil (o) fills a narrow gap with moisture (w) in the state of microdrops.

6 is a perspective view showing a coupling structure of the cylinder 240 of the compressor according to the first embodiment, and FIG. 7 is a cross-sectional view showing an enlarged portion B in FIG. 6. In addition, FIG. 8 is a diagram for explaining a phenomenon in which oil does not proceed to the inside of the cylinder 240 due to friction.

6 and 7, the compressor according to the embodiment of the present specification forms a gas inlet 232 that is recessed radially inward from the outer circumferential surface of the cylinder body 241 and extends in a circular shape along the outer circumferential surface. do. A part of the gas inlet 232 communicates with the gas hole, and lubricating gas may be supplied through the gas hole.

In addition, a gas receiving groove 234 that is concaved so as to extend by a predetermined angle in the circumferential direction may be formed on the inner peripheral surface of the cylinder body 241. In addition, a plurality of gas receiving grooves 234 may be provided in the circumferential direction, and the plurality of gas receiving grooves 234 may be disposed to be spaced apart at equal intervals. For example, the gas receiving groove 234 is concave to extend by an angle between about 15 degrees to 45 degrees in the circumferential direction, and the three gas receiving grooves 234 are spaced at equal intervals at an angle of 120 degrees in the circumferential direction. Can be placed.

In addition, a gas receiving groove 234 located in front of the cylinder body 241 corresponding to the first gas inlet 232a and a gas receiving groove located behind the cylinder body 241 corresponding to the second gas inlet 232b. The grooves 234 may be disposed to be staggered from each other. For example, the gas receiving groove 234 positioned in front of the cylinder body 241 may be disposed so as to alternate with the gas receiving groove 234 positioned in front of the cylinder body 241 at an angle of 60 degrees.

In addition, the gas receiving groove 234 located in front of the cylinder body 241 corresponding to the first gas inlet 232a and the gas located behind the cylinder body 241 corresponding to the second gas inlet 232b The receiving grooves 234 may be disposed so as not to overlap each other in a direction parallel to the axial direction.

In addition, the gas receiving groove 234 may be formed at a position opposite to the gas inlet 232. That is, the gas receiving groove 234 is disposed close to the gas inlet 232 and may be disposed on the inner surface of the circumference formed by the gas inlet 232.

In addition, the gas receiving groove 234 may communicate with the gas inlet 232 through the nozzle part 233. For example, the nozzle part 233 may penetrate radially from the center of the gas receiving groove 234 to form a hole communicating with the gas inlet 232.

The nozzle portion 233 is usually processed to a diameter of several tens of micrometers. However, during the repeated use period of the compressor, the oil that has penetrated into the gas inlet 232 is deposited in the nozzle 233, causing frequent clogging. As such, when oil is deposited on the nozzle unit 233, surface adhesive force is applied, so that it does not escape even by the pressure applied during the compression stroke of the piston 150.

The compressor 200 according to the exemplary embodiment of the present specification may prevent oil from being deposited in the nozzle unit 233 by forming the gas receiving groove 234. This is because if the outlet of the nozzle unit 233 directly contacts or is very close to the piston 150, the oil of the nozzle unit 233 is deposited, thereby increasing the likelihood of clogging.

The depth of the gas receiving groove 234 may be continuously changed in the circumferential direction. For example, the concave surface of the gas receiving groove 234 may form a curvature greater than that of the inner circumferential surface of the cylinder body 241. In this case, the nozzle part 233 is communicated to the deepest part of the gas receiving groove 234, and a space between the piston 150 and the nozzle part 233 can be secured. In addition, as the depth of the water receiving groove 234 is continuously reduced along the circumference of the piston 150, the refrigerant gas supplied through the nozzle unit 233 is easily diffused between the piston 150 and the cylinder body 141. can do.

In addition, the compressor 200 according to the exemplary embodiment of the present specification narrows the gap between the gas pocket 231 serving as a flow path for the refrigerant gas between the frame 220 and the cylinder 240 to prevent the movement of the infiltrated oil and It can be collected inside the pocket 231. The gas pocket 231 may have a cylindrical strip shape formed in a space between the inner circumferential surface of the frame body 221 and the outer circumferential surface of the cylinder body 241, and both ends thereof are sealed with sealing members 250 and 251. For example, the front end may be sealed with the first sealing member 250 and the rear end may be sealed with the second sealing member 251.

Usually, in a compressor using a gas bearing means, the spacing between the gas pockets 231 is about 150 micrometers. As such, it is possible to facilitate the assembly process by setting a margin corresponding to the assembly tolerance.

In the embodiment of the present specification, the distance between the gas pockets 231 is in the range of 10 to 30 micrometers. That is, a gap (tolerance) between the inner circumferential surface of the frame body 221 and the outer circumferential surface of the cylinder 240 is provided in the range of 10 to 30 micrometers.

Referring to FIG. 8, when the gap between the gas pockets 231 is 30 micrometers or less, the oil (o) cannot be introduced into the gas inlet 232 due to the surface frictional force of the gas pocket 231. The surface frictional force of the oil increases as the gap between the gas pockets 231 decreases, and this is related to the compression of the oil (o) as the gap between the gas pockets 231 decreases. That is, when the gap between the gas pockets 231 is 30 micrometers, the magnitude of the frictional force of the oil (o) and the stress applied to the oil (o) are the same, or the magnitude of the frictional force becomes larger.

In addition, the oil (o) collected in the gap of the gas pocket 231 can be expected to serve as a filter to trap foreign substances moving to the sliding part.

In addition, when the gap between the gas pockets 231 is 10 micrometers or more, the pressure drop in the area of the gas inlet 232 satisfies the lubrication performance criterion of 0.35 bar.

In this way, the structure that prevents oil from penetrating into the sliding part by reducing the assembly tolerance between the cylinder 240 and the frame 220 improves reliability without increasing cost because it does not add a specific part or add a processing process. This is how you can make it.

9 is a cross-sectional view showing a modified embodiment of FIG. 7.

Referring to FIG. 9, a collecting groove 235 may be formed on the inner circumferential surface of the frame body 221 to collect oil or foreign matter in the gap of the gas pocket 231. The collecting groove 235 may be formed to extend in the circumferential direction. The collection grooves 235 may be formed to extend 360 degrees in a circle, or may be provided in a circumferential direction with a plurality of spaced apart.

The collecting groove 235 may be formed on the inner circumferential surface of the frame body 221 or may be formed on the outer circumferential surface of the cylinder body 241. However, in order to prevent the cylinder 240 from being deformed, it may be desirable to be formed on the inner circumferential surface of the frame body 221.

Since the collecting groove 235 has a relatively larger depth than the gap gap of the gas pocket 231, the oil or foreign matter collected in the collecting groove 235 does not flow into the gas pocket 231 again, but the collecting groove 235 Will remain within.

10 is a cross-sectional view showing another modified embodiment of FIG. 7.

Referring to FIG. 10, a porous material 235a capable of absorbing oil or foreign matter may be inserted into the collection groove 235. The porous material 235a may be provided in a shape corresponding to the shape of the collecting groove 235. For example, when the collection groove 235 extends 360 degrees in the circumferential direction, the porous material 235a may be provided in a ring shape.

The porous material 235a may be designed to minimize flow resistance of the refrigerant gas while absorbing oil or foreign matter. For example, the porous material 235a may have voids so that only particles having a diameter of 5 micrometers or less can pass.

11 is a perspective view showing a cylinder 240 according to a comparative embodiment.

The cylinder 240 may form a gas inlet 232 (232a, 232b) that is a passage through which the refrigerant gas provided from the gas hole 224 of the frame 220 passes. The gas inlet 232 may be a groove formed by concaving in the outer circumferential surface of the cylinder 240 in the circumferential direction. The gas inlet 232 includes a first gas inlet 232a positioned in front of the cylinder 240 and a second gas inlet 232b positioned in the rear of the cylinder 240.

The first gas inlet 232a and the second gas inlet 232b may communicate with each other through a gas pocket 231 formed between the cylinder 240 and the frame 220.

In addition, the cylinder 240 has a nozzle portion 233 (233a, 233b) passing through the gas inlet portion 232 in the radial direction, and the nozzle portion 233 is formed in the circumferential direction of the gas inlet portion 232 A plurality may be provided. A plurality of first nozzle portions 233a may be formed in the first gas inlet portion 232a, and a plurality of second nozzle portions 233b may be formed in the second gas inlet portion 232b.

Specifically, the first gas inlet portion 232a and the first nozzle portion 233a are formed at a position spaced apart from the front end of the cylinder body 241 by a first distance, and the second gas inlet portion 232b And the second nozzle part 233b are formed at a position spaced apart from the front end of the cylinder body 241 by a second distance greater than the first distance. In addition, the third distance from the front end of the cylinder body 241 to the center may be larger than the first distance and smaller than the second distance.

Meanwhile, the first gas inlet 232a is formed at a position adjacent to the outlet of the gas hole 224. For example, the outlet portion of the gas hole 224 and the first gas inlet portion 232a may be disposed to partially overlap each other.

Since the internal pressure of the cylinder 240 is formed relatively high at a position close to the discharge side of the refrigerant, that is, inside the first gas inlet 232a, the outlet of the gas hole 224 is in the first gas inlet 232a. By positioning adjacent to each other, a relatively large amount of refrigerant can be introduced into the cylinder 240 through the first gas inlet 232a. As a result, by enhancing the function of the gas bearing, it is possible to prevent wear of the cylinder 240 and the piston 150 during the reciprocating movement of the piston 150.

In addition, referring to FIG. 7, a cylinder filter member 232c may be installed in the gas inlet 232. The cylinder filter member 232c blocks foreign substances of a predetermined size or more from flowing into the cylinder body 241 and absorbs oil contained in the refrigerant. Here, the predetermined size may be 1 μm.

The cylinder filter member 232c may be a thread filter 232c provided in the shape of a thread wound 30 to 70 times with a constant tension on the gas inlet 232. In detail, the thread filter 232c may be made of polyethylene terephthalate (PET) or polytetrafluoroethylene (PTFE) and have a predetermined thickness or diameter.

The seal filter 232c serves as a filter to block fine dirt and oil contained in the refrigerant gas. In addition, the seal filter 232c also functions as a restrictor (flow restrictor) for reducing the pressure of the refrigerant gas introduced from the gas bearing system.

However, the thread filter 232c has several problems.

The thread filter 232c may be fixed to the surface of the cylinder body 241 by winding a thread around the cylinder body 241 and heat-sealing a portion of the surface. As a result, as time elapses, the heat-sealed portion is damaged and the tension decreases. If the tension of the seal filter 232c is decreased, not only the filter function but also the restrictor function may be weakened, and the performance of the gas bearing may be deteriorated.

In addition, the thread filter 232c is fastened by winding a thread by applying tension to the gas inlet 232 grooved in the cylinder body 241, and at this time, there is a possibility that deformation may occur in the cylinder body 241. And, for this reason, the performance of the gas bearing may be deteriorated.

12 is a perspective view showing a cylinder 240 according to the second embodiment, and FIG. 13 is a cross-sectional view showing a coupling structure of the cylinder 240 of the compressor 200 according to the second embodiment.

12 and 13, the cylinder 240 according to the second embodiment of the present invention has a supply passage 243 concave into the outer circumferential surface of the cylinder body 241, and the supply passage 243 is a frame inclined portion. It communicates with the gas hole 224 formed in 223. In addition, the air supply passage 243 may form a part of the gas pocket 231 partitioned by an interval between the cylinder body 241 and the piston body 150.

14 and 2, the gas hole 224 of FIG. 2 extends from the frame flange 222 along the frame inclined portion 223 in an inclined direction to be connected to the inner circumferential surface of the frame main body 221. That is, the gas hole 224 provides the refrigerant gas into the frame body 221 through an inclined passage.

However, the gas hole 224-1 of FIG. 14 extends parallel to the axial direction from the frame flange 222 and is bent inward at a point past the rear end of the cylinder flange 242 and extends perpendicular to the axial direction. 221). That is, the gas hole 224-1 provides the refrigerant gas into the frame body 221 through the bent passage.

Compared to the inclined gas hole 224 of FIG. 2, the bent gas hole 224-1 of FIG. 14 increases fluid resistance at the bent portion and thus the flow velocity may be relatively reduced. The bent portion includes a portion in which the gas hole 224-1 in the axial direction is bent in the vertical direction and a portion in which the gas hole 224-1 in the vertical direction is connected to the gas pocket 231 inside the frame inclined portion 223. I can. In addition, the bent gas hole 224-1 may supply the refrigerant gas to a position closer to the front of the cylinder body 241 compared to the inclined gas hole 224.

The air supply passage 243 may include a first direction air supply passage 243a extending in the longitudinal direction of the cylinder body 241 and a second direction air supply passage 243b extending in the circumferential direction of the cylinder body 241. have. The restrictor area 248 is provided so that the first direction supply passage 243a and the second direction supply passage 243b cross each other, and is divided into a first direction supply passage 243a and a second direction supply passage 243b. Can be formed.

A plurality of first direction air supply passages 243a may be formed along the circumference of the cylinder body 241. In addition, the first direction air supply passage 243a may extend in a direction parallel to the axial direction, and may be formed at equal intervals along the circumference of the cylinder body 241. For example, four first-direction air supply passages 243a may be formed at intervals of 90 degrees along the circumference of the cylinder body 241.

A plurality of second direction air supply passages 243b may be formed along the length of the cylinder body 241. In addition, the second direction air supply passage 243b may extend in a direction perpendicular to the axial direction, and may be formed at equal intervals along the longitudinal direction of the cylinder body 241. For example, the second direction air supply passage 243b includes a second direction first air supply passage 243b-1 and a second direction second air supply passage 243b-2 formed in front of the cylinder body 241 can do. And the second direction air supply passage 243b is a second direction third air supply passage 243b formed from the second installation groove 241a in which the second sealing member 251 is seated into a space in front of the second sealing member 251. -3) may be included.

In addition, the first air supply passage 243b-1 in the second direction may be positioned so as to partially overlap with the gas hole 224-1. Therefore, the refrigerant gas flowing through the gas hole 224-1 may be directly introduced into the first supply passage 243b-1 in the second direction.

A grid-shaped restrictor region 248 may be formed on an outer circumferential surface of the cylinder body 241 formed by intersecting the first direction air supply passage 243a and the second direction air supply passage 243b.

In the drawing, 2 in the longitudinal direction of the cylinder 240, 4 in the circumferential direction, a total of 8 restrictor areas 248 are formed, and each restrictor area 248 is a supply port communicating with the inside of the cylinder 240 It is shown that 244 is provided. In addition, each of the restrictor regions 248 may all have the same area. Alternatively, the restrictor area 248 in front of the cylinder 240 and the restrictor area 248 in the rear of the cylinder 240 may have different widths.

The front side of the first direction supply passage 243a starts from the second direction first supply passage 243b-1, and the rear side of the first direction supply passage 243a is the second direction second supply passage 243b-2. It may extend to the second installation groove (241a). Previously, it has been described that the second installation groove 241a can function as the third air supply passage 243b-3 in the second direction.

A supply port 244 penetrating the cylinder body 241 may be formed in the restrictor region 248 partitioned between the first direction supply passage 243a and the second direction supply passage 243b. For example, the air supply port 244 may have a circular cross section, the diameter of the air supply port 244 is 35 micrometers, and eight may be provided on the surface of the cylinder body 241.

The air supply port 244 may be positioned so that the distance between the air supply passages 243a in the first direction on both sides adjacent to each other is the same. In addition, the air supply port 244 may be positioned so that the distance between the second direction supply passage 243b in the front and the second direction supply passage 243b in the rear may be different. For example, the air supply port 244 between the first air supply passage 243b-1 in the second direction and the second air supply passage 243b-2 in the second direction is connected to the first air supply passage 243b-1 in the second direction. The distance may be located closer, and the air supply port 244 between the second air supply passage 243b-2 in the second direction and the third air supply passage 243b-3 in the second direction is a third air supply passage in the second direction. It can be located closer to (243b-3).

14 is a diagram showing the flow of the refrigerant in FIG. 12.

Referring to FIG. 14, the refrigerant gas flowing through the gas hole 224-1 is accommodated in the gas pocket 231, but is primarily diffused through the supply passage 243 having a small flow resistance, and the supply passage 243 The refrigerant gas filled in) is secondarily diffused along the gap between the cylinder body 241 and the frame body 221 in the restrictor region 248 and flows into the air supply port 244. In addition, the refrigerant gas introduced into the air supply port 244 is filled in the space between the cylinder 240 and the piston and performs a bearing function.

FIG. 15 is an enlarged view of portion C in FIG. 13.

Referring to FIG. 15, impurities (such as dirt and oil) introduced through the gas hole 224-1 may pass through a supply passage 243 having a relatively wide flow path space. However, since the flow of the tom leak between the cylinder body 241 and the frame body 221 in the restrictor area 248 having a relatively narrow flow path space is prevented, the filter function can be performed without having a separate filter. Therefore, when the refrigerant in the air supply passage 243 flows into the air supply port 244, the refrigerant from which impurities have been removed may flow.

Specifically, the air supply passage 243 has a width and a width of 0.1 mm or more, and a distance between the cylinder body 241 and the frame body 221 is provided with a size of 10 micrometers or less. Under this size condition, movement of impurities from the air supply passage 243 to the air supply 244 may be blocked.

In addition, a distance between the outer circumferential surface of the cylinder body 241 and the inner circumferential surface of the frame body 221, that is, the gap (gap) of the gas pocket 231 may be in the range of 5 to 30 micrometers. Preferably it may be in the range of 5 to 10 micrometers.

In addition, the air supply passage 243 may be provided to have a width and depth of 0.1 mm or more. When the width and depth of the air supply passage 243 satisfies 0.1 mm, it was confirmed that no pressure drop occurred while the refrigerant gas passed through the air supply passage 243.

Refrigerant gas passes through the air supply passage 243 having a width and depth of 0.1 mm or more and no pressure drop occurs, but the restrictor region where the distance between the air supply passage 243 and the air supply 244 is 10 micrometers or less. A pressure drop occurs as it passes (248). Accordingly, the supply passage 243 serves to deliver the refrigerant of the same pressure to the restrictor area 248 divided by the supply passage 243 on the outer periphery of the cylinder body 241, and the supply port ( The gas pockets 231 between 244 may serve as a restrictor for lowering the pressure of the refrigerant and may be referred to as a restrictor area 248.

In addition, since the area of the restrictor area 248 divided by the air supply passage 243 is the same, the flow resistance of the refrigerant is the same in the gap between the frame extending to each supply port 244 and the cylinder 240. Accordingly, the same refrigerant flow rate can pass through each supply port 244 under the same pressure condition.

In addition, the area of the restrictor area 248 divided by the air supply passage 243 according to the position of each air supply port 244 and the size of the gap between the frame extending to each air supply port 244 and the cylinder 240 If changed, the flow resistance can be different. Therefore, the refrigerant flow rate of each supply port 244 may be different under the same pressure condition.

Meanwhile, the reason why the size of the air supply passage 243 and the size of the gap between the frame and the cylinder 240 are set will be described based on FIGS. 16 and 17. 16 and 17 show that numerical analysis was performed while changing the size of the gap between the frame and the cylinder 240 and the width of the air supply passage 243, and the applicability of the present invention was confirmed through the analysis result.

16 is a graph showing a difference in flow rate when the width of the air supply passage 243 is changed.

FIG. 16A shows the case of the comparative example shown in FIG. 11, and shows the flow rate of a single cylinder 240 when the nozzle part has a diameter of 35 micrometers and 8 is provided in the cylinder body 241. Referring to the graph, it can be seen that as the supply pressure increases, the fluid resistance increases and the increase rate of the flow rate decreases.

FIG. 16B shows the flow rate of a single cylinder 240 when the width and depth of the air supply passage 243 is 1 mm and the gap between the gas pocket 231 is 5 μm. Referring to the graph, it can be seen that the rate of increase of the flow rate is constant even when the air supply pressure increases.

FIG. 16C shows the flow rate of a single cylinder 240 when the width and depth of the air supply passage 243 is 3 mm and the gap between the gas pockets 231 is 5 μm. Referring to the graph, it can be seen that the rate of increase of the flow rate is constant even when the air supply pressure increases.

From the above results, it can be seen that when the width and depth of the air supply passage 243 are 1 mm or more, the pressure drop does not occur. Meanwhile, the maximum values of the width and depth of the air supply passage 243 may be determined in consideration of the rigidity of the cylinder body 241. This is because, when the width and depth of the air supply passage 243 are increased, the flow rate of the refrigerant gas increases, but there may be a problem that the rigidity of the cylinder body 241 decreases.

17 is a graph showing the difference in flow rate when the gap between the frame and the cylinder 240 is different.

FIG. 17A shows the flow rate of a single cylinder 240 when the width and depth of the air supply passage 243 is 3 mm, and the gap between the gas pockets 231 is 5 μm. Same as (c). Referring to the graph, it can be seen that the rate of increase of the flow rate is constant even when the supply air pressure increases.

FIG. 17B shows the flow rate of a single cylinder 240 when the width and depth of the air supply passage 243 is 3 mm, and the gap between the gas pockets 231 is 4 μm. Referring to the graph, it can be seen that the rate of increase of the flow rate is constant even when the supply pressure increases, but the rate of increase of the flow rate decreases according to the pressure increase.

FIG. 17C shows the flow rate of a single cylinder 240 when the width and depth of the air supply passage 243 is 3 mm and the gap between the gas pockets 231 is 3 μm. Referring to the graph, it can be seen that the increase rate of the flow rate is constant even when the supply air pressure increases, but the increase rate of the flow rate decreases further with the increase of the pressure.

From the above results, when the width and depth of the air supply passage 243 is 3 mm, it can be confirmed that the increase in flow rate according to the pressure increase is smooth when the distance between the gas pockets 231 is 5 μm.

On the other hand, when the distance between the gas pockets 231 is 30 micrometers or less, oil may not flow into the air supply port 244 due to the surface frictional force of the gas pocket 231.

That is, the gap between the gaskets may be provided within a range of 5 to 30 micrometers.

18 is a perspective view showing a cross-section of a frame 220-1 to describe a supply passage 245 according to the second embodiment.

18, the air supply passage 245 according to the second embodiment is formed on the inner peripheral surface of the frame body 221, not the outer peripheral surface of the cylinder body 241, the air supply passage 245 is the frame inclined portion 223 It communicates with the gas hole 224-1 formed in the. In addition, the air supply passage 245 may form a part of the gas pocket 231 partitioned by an interval between the cylinder body 241 and the piston body.

The air supply passage 245 may include a first direction air supply passage 245a extending in the longitudinal direction of the frame body 221 and a second direction air supply passage 245b extending in the circumferential direction of the frame body 221. have. The first direction air supply passage 245a and the second direction air supply passage 245b may be provided to cross each other.

A plurality of first direction air supply passages 245a may be formed along the circumference of the frame body 221. For example, four first-direction air supply passages 245a may be formed at intervals of 90 degrees along the circumference of the frame body 221.

A plurality of second direction air supply passages 245b may be formed along the length of the frame body 221. For example, in the second direction air supply passage 245b, a second direction first air supply passage 245b-1 and a second direction second air supply passage 245b-2 formed in front of the frame body 221 are formed. Can be. In addition, a space in front of the second sealing member 251 in the groove in which the second sealing member 251 is seated may function as a third air supply passage 245b-3 in the second direction.

In addition, the first air supply passage 245b-1 in the second direction may be positioned to directly communicate with the gas hole 224-1. Accordingly, the refrigerant gas flowing through the gas hole 224-1 may be directly introduced into the first air supply passage 245b-1 in the second direction.

The outer circumferential surface of the frame body 221 formed by intersecting the first direction air supply passage 245a and the second direction air supply passage 245b may form a grid-shaped restrictor region 248-1. According to the above example, 4 in the circumferential direction, 2 in the length direction, and a total of 8 grid-shaped restrictor regions 248-1 may be formed.

The front side of the first direction supply passage 245a starts from the second direction first supply passage 245b-1, and the rear side of the first direction supply passage 245a passes through the second direction second supply passage 245b-2. It may extend to the groove in which the second sealing member 251 is seated. Previously, it has been described that the groove in which the second sealing member 251 is seated may function as the third air supply passage 245b-3 in the second direction.

The air supply port 244 may be formed in the cylinder body 241 corresponding to the restrictor area 248-1. In a state in which the frame 220-1 and the cylinder 240 are coupled, the air supply 244 may be positioned so that the distance between the first air supply passages 245a on both sides adjacent to each other is the same. In addition, the air supply port 244 may be positioned so that a distance between the second direction air supply passage in the front and the second air supply passage in the rear direction is different. For example, the air supply port 244 between the first air supply passage 245b-1 in the second direction and the second air supply passage 245b-2 in the second direction is connected to the first air supply passage 245b-1 in the second direction. The distance may be located closer, and the air supply port 244 between the second air supply passage 245b-2 in the second direction and the third air supply passage 245b-3 in the second direction is a third air supply passage in the second direction. It can be located closer to (245b-3).

Meanwhile, the supply passages 243 and 245 may be formed only on the outer circumferential surface of the cylinder body 241 or may be formed only on the inner circumferential surface of the frame body 221, or may be formed simultaneously on the outer circumferential surface of the cylinder body 241 and the inner circumferential surface of the frame body 221. have. In the latter case, the air supply passage 243 formed on the outer circumferential surface of the cylinder body 241 and the air supply passage 245 formed on the inner circumferential surface of the frame body 221 may be formed at positions facing each other or may be formed at alternate positions.

19 is a diagram showing various embodiments of a cross-sectional shape of an air supply passage 243.

Referring to FIG. 19, the cross-sectional shape of the air supply passage 243 may be provided in various shapes. For example, the cross-sectional shape of the air supply passage 243 may be provided as a square 243, a part of a circle 243-2, a narrow trapezoid 243-3, and a triangle 243-4. In addition, when the cross-sectional shape of the air supply passage 243-1 is provided in a polygonal shape, the corners may be rounded. In addition, when the cross-sectional shape of the air supply passage 243-5 is provided in a triangular shape, it may be provided in an asymmetric shape inclined to one side instead of a symmetric shape. That is, one side of the air supply passage 243-5 may be concave vertically and the other side may be provided to be inclined.

20 is a perspective view showing a cylinder 240-2 according to the third embodiment.

Referring to FIG. 20, the cylinder 240-2 according to the third embodiment includes the width or depth of the supply passage 243 in front of the cylinder 240-2 and the supply passage 243 at the rear of the cylinder 240-2. May be provided differently.

The first-direction supply passage 243a includes a first-direction first supply passage 243a-1 that connects the second-direction first supply passage 243b-1 and the second-direction second supply passage 243b-2. The second air supply passage 243a-2 in the first direction connecting the second air supply passage 243b-2 in the second direction and the third air supply passage 243b-3 in the second direction may have different widths or depths. have. For example, the width of the first air supply passage 243a-1 in the first direction may be wider than the width of the second air supply passage 243a-2 in the first direction. Since the flow resistance of the first air supply passage 243a-1 in the first direction is smaller than the flow resistance of the second air supply passage 243a-2 in the first direction, the air supply passage 243 in front of the cylinder 240-2 is The flow of refrigerant passing through becomes larger.

And the second direction air supply passage 243b is the width of the first air supply passage 243b-1 in the second direction, the second air supply passage 243b-2 in the second direction, and the third air supply passage 243b-3 in the second direction. Alternatively, different depths may be provided. For example, the width of the second air supply passage 243b-2 in the second direction may be larger than the width of the third air supply passage 243b-3 in the second direction. Since the flow resistance of the second air supply passage 243b-2 in the second direction is smaller than the flow resistance of the third air supply passage 243b-3 in the second direction, the air supply passage 243 in front of the cylinder 240-2 is The flow of refrigerant passing through becomes larger.

In addition, the restrictor area 248 is surrounded by a first air supply passage 243a-1 in the first direction, a first supply air supply passage 243b-1 in the second direction, and a second supply passage 243b-2 in the second direction. It is surrounded by the 1 restrictor area 248a, the second air supply passage 243a-2 in the first direction, the second air supply passage 243b-2 in the second direction, and the third air supply passage 243b-3 in the second direction. 2 The restrictor area 248b may have different widths. As mentioned above, when the area of the air supply passage 243 in front of the cylinder 240-2 is larger, the width of the first restrictor area 248a is smaller than the width of the second restrictor area 248b. I can.

21 is a diagram illustrating various embodiments of the restrictor area 248.

Referring to FIG. 21, the restrictor area may include a square shape 248, a circular shape 248-1, an elliptical shape, or a partial shape 248-2 of a circular or elliptical shape. In addition, the first restrictor area 248a in front of the cylinder 240 and the second restrictor area 248b in the rear of the cylinder 240 may have different areas. As the area of the first restrictor area 248a in front of the cylinder 240 increases, the width of the air supply passage 243 that divides the first restrictor area 248a increases, A large flow of refrigerant can pass.

Certain or other embodiments of the present specification described above are not mutually exclusive or distinct from each other. Certain or other embodiments of the present specification described above may have their respective configurations or functions used in combination or combination.

For example, it means that a configuration A described in a specific embodiment and/or a drawing may be combined with a configuration B described in another embodiment and/or a drawing. That is, even if the combination between the components is not directly described, the combination is possible except for the case where the combination is described as impossible.

The above detailed description should not be construed as limiting in all respects and should be considered as illustrative. The scope of this specification should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of this specification are included in the scope of this specification.

100: compressor, 101: accommodating space,
102: suction space, 103: compression space,
104: discharge space, 110: casing,
111: shell, 112: first shell cover,
113: second shell cover, 114: suction pipe,
115: discharge pipe, 115a: loop pipe,
116: first support spring, 116a: suction guide,
116b: suction side support member, 116c: damping member,
117: second support spring, 117a: support bracket,
117b: first support guide, 117c: support cover,
117d: second support guide, 117e: third support guide,
118: resonant spring, 118a: first resonant spring,
118b: second resonant spring, 119: spring supporter,
119a: body portion, 1 19b: coupling portion,
119c: support, 120: frame,
121: body portion, 122: flange portion,
123: back cover, 123a: support bracket,
130: drive unit, 131: outer stator,
132: coil winding body, 132a: bobbin,
132b: coil, 133: stator core,
134: inner stator, 135: mover,
136: magnet frame, 136a: coupling portion,
137: stator cover, 140: cylinder,
141: flange portion, 142: gas inlet,
150: piston, 151: head,
152: guide portion, 153: flange portion,
154: suction port, 155: suction valve,
160: muffler unit, 161: suction muffler,
161a: flange portion, 162: inner guide,
170: discharge valve assembly, 171: discharge valve,
172: valve spring, 180: discharge cover assembly,
181: first discharge cover, 182: second discharge cover,
183: third discharge cover,
200: compressor, 220: frame,
221: frame body, 221a: third installation groove,
222: frame flange, 223: frame slope,
224: gas hole, 225a: first wall,
225b: second wall, 225c: third wall,
225d: frame space, 225e: guide groove,
226: sealing member seating portion, 226a: first installation groove,
227: filter groove, 228: filter sealing member,
229a: fastening hole, 229b: terminal insertion part,
230: discharge filter, 231: gas pocket,
232: gas inlet, 232c: cylinder filter member,
233: nozzle part, 234: gas receiving groove,
235: collection groove, 235a: porous material,
240: cylinder, 241: cylinder body,
241a: second mounting groove, 242: cylinder flange,
243a: first direction air supply passage, 243b: second direction air supply passage,
244: air supply, 248: restrictor area,
250: first sealing member, 251: second sealing member,
252: third sealing member.

Claims (20)

A cylinder that forms a compression space in which a piston reciprocates in an axial direction to compress a refrigerant gas in a space formed inside a cylindrical cylinder body;
A frame in which the cylinder is accommodated in a space formed inside, one side communicates with the outside to allow refrigerant gas to flow in, and the other side has a gas hole communicating with a gas pocket including a space between the inner circumferential surface and the outer circumferential surface of the cylinder Including,
The cylinder is provided with a gas inlet part communicating with the gas pocket on one side and communicating with the space formed in the cylinder on the other side,
The gas pocket is a compressor in which a distance between the inner circumferential surface of the frame and the outer circumferential surface of the cylinder is provided in a range of 10 to 30 micrometers so that a surface friction force is greater than or equal to the stress applied to the oil contained in the refrigerant gas. .
The method of claim 1,
The frame,
A frame body having a cylindrical shape for accommodating the cylinder, and a frame flange extending radially outward from the front of the body and to which a driving unit driving the piston is connected,
The gas hole is a compressor in which one side communicates with the front of the frame flange and the other side communicates with the inside of the frame body.
The method of claim 2,
The frame further includes a frame connection part connecting the frame body and the frame flange,
The gas hole is a compressor that penetrates the frame connection portion in a direction inclined to an axial direction.
The method of claim 1,
A front sealing member interposed between the cylinder and the frame in front of the gas hole to seal the front of the gas pocket;
Further comprising a rear sealing member interposed between the cylinder and the frame at the rear of the gas hole to seal the rear of the gas pocket,
The gas pocket is provided as a space between the front sealing member and the rear sealing member.
The method of claim 4,
The gas inlet portion is formed to be concave inward from the outer circumferential surface of the cylinder in the radial direction, and is provided with a plurality of the axial direction
Any one of the plurality of gas inlet portions is provided to partially overlap the other side of the gas hole.
The method of claim 5,
The gas inlet portion is a compressor extending in a circumferential direction along an outer circumferential surface of the cylinder.
The method of claim 6,
A compressor having a gas receiving groove formed on an inner circumferential surface of the cylinder that communicates with the gas inlet part, is concave outward in a radial direction, and has a plurality of gas receiving grooves provided in the axial direction.
The method of claim 7,
The gas receiving groove is a compressor extending in a circumferential direction at an angle within 180 degrees with respect to a central axis along the inner circumferential surface of the cylinder.
The method of claim 8,
The gas receiving groove is concave in the shape of a concave curved surface having a radius of curvature smaller than the radius of curvature of the inner circumferential surface of the cylinder.
The method of claim 8,
The plurality of gas receiving grooves are provided in the axial direction, and the compressor is arranged to be shifted in a direction parallel to the axial direction.
The method of claim 9,
The gas receiving grooves disposed in the axial direction are disposed so as not to overlap in a direction parallel to the axial direction.
The method of claim 4,
A compressor having a collecting groove formed on an inner circumferential surface of the frame body or an outer circumferential surface of the cylinder, which communicates with the gas pocket and is concave in a radial direction to collect oil or foreign matter.
The method of claim 12,
The collecting groove is formed on an inner circumferential surface of the frame body and extends in a circumferential direction.
The method of claim 12,
The collecting groove is a compressor into which a porous material is inserted.
The method of claim 14,
The porous material is a compressor in which pores having a size capable of passing only particles having a diameter of 5 micrometers or less are formed.
The method of claim 14,
The collection groove extends 360 degrees in the circumferential direction of the frame body,
The porous material is a compressor provided in a ring shape in the collection groove.
A cylinder body having a cylindrical shape and a cylinder flange extending radially outward from the front of the cylinder body, and a piston reciprocating in the axial direction to a space formed inside the cylinder body to form a compression space for compressing refrigerant gas Cylinder;
A frame body accommodating the cylinder body therein, and a frame flange extending radially outward from the front of the frame body and coupled to the cylinder flange, and one side communicates with the outside to allow refrigerant gas to flow in and the other side A frame in which a gas hole communicating with a gas pocket including a space between an inner circumferential surface of the frame body and an outer circumferential surface of the cylinder body is formed;
A front sealing member interposed between the cylinder and the frame in front of the gas hole to seal the front of the gas pocket; And
And a rear sealing member interposed between the cylinder and the frame at the rear of the gas hole to seal the rear of the gas pocket,
The cylinder body is formed with a gas inlet part communicating with the gas pocket on one side and communicating with the space formed in the cylinder body on the other side,
A collecting groove is formed on the inner circumferential surface of the frame body or the outer circumferential surface of the cylinder body, which communicates with the gas pocket and is concave in a radial direction to collect oil or foreign matter,
The collecting groove is spaced apart from the gas inlet in the axial direction and is formed to have a greater depth than the gap between the gas pockets.
The method of claim 17,
The collecting groove is formed on an inner circumferential surface of the frame body and extends in a circumferential direction.
The method of claim 17 or 18,
The collecting groove is a compressor into which a porous material is inserted.
The method of claim 19,
The porous material is a compressor in which pores having a size capable of passing only particles having a diameter of 5 micrometers or less are formed.

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