KR102303544B1 - Scroll compressor - Google Patents

Abstract

A scroll compressor according to the present invention includes: a frame coupled to a first scroll to support a second scroll; a sealing member insertion groove formed in an annular shape on at least one of one side of the second scroll or one side of the frame in contact with the second scroll; and a sealing member formed in an annular shape and inserted into the sealing member insertion groove and configured to radially separate a distance between the second scroll and the frame, wherein the sealing member has a cross-sectional area of an inner circumferential surface greater than a cross-sectional area of an outer circumferential surface It is formed to be small, and a second interval between the outer circumferential surface of the sealing member and the outer wall surface of the sealing member insertion groove is smaller than or equal to the first interval between the inner circumferential surface of the sealing member and the inner wall surface of the sealing member insertion groove.

Description

Scroll Compressor {SCROLL COMPRESSOR}

The present invention relates to a scroll compressor, and more particularly, to a compressor in which a compression unit is located below a transmission unit.

A scroll compressor is a compressor that engages with a plurality of scrolls and performs a relative rotational motion while forming a compression chamber composed of a suction chamber, an intermediate pressure chamber, and a discharge chamber between both scrolls. Such a scroll compressor can obtain a relatively high compression ratio compared to other types of compressors, and a stable torque can be obtained by smoothly performing refrigerant suction, compression, and discharge strokes. Accordingly, scroll compressors are widely used for refrigerant compression in air conditioners and the like. Recently, a high-efficiency scroll compressor with an operating speed of 180 Hz or higher by reducing the eccentric load has been introduced.

The scroll compressor may be divided into a low-pressure type in which a suction pipe communicates with an inner space of a casing forming a low-pressure part, and a high-pressure type in which a suction pipe communicates directly with a compression chamber. Accordingly, the low-pressure type driving part is installed in the suction space of the low-pressure part, whereas the high-pressure type driving part is installed in the discharge space of the high-pressure part.

Such a scroll compressor can be divided into an upper compression type and a lower compression type depending on the positions of the driving unit and the compression unit. When the compression unit is located above the driving unit, it is called an upper compression type. On the contrary, when the compression unit is located below the driving unit, it is called a bottom compression type.

In a scroll compressor, as the pressure in the compression chamber increases, the orbiting scroll receives a gas force in a direction away from the fixed scroll. Then, as the orbiting scroll moves away from the fixed scroll, leakage between the compression chambers occurs and the compression loss increases.

In consideration of this, in the scroll compressor, a tip seal method of inserting a sealing member into the front end surfaces of the fixed wrap and the orbiting wrap is applied, or a back pressure chamber forming an intermediate pressure or a discharge pressure is formed on the rear surface of the orbiting scroll or the fixed scroll to form the back pressure chamber. The back pressure method is applied in which the orbiting scroll or the fixed scroll is pressurized by the opposing scroll with the pressure of

In particular, in the back pressure method, a method is known in which a sealing member is installed between the rear surface of the orbiting scroll (or the rear surface of the fixed scroll) and a frame corresponding thereto so that a back pressure chamber is formed inside or outside the sealing member. In the back pressure method using such a sealing member, an annular groove is formed in one member constituting the thrust surface, and an annular sealing member having a square cross-section is inserted into the annular groove. Then, the medium pressure refrigerant compressed in the compression chamber during operation of the compressor flows into the annular groove, and the sealing member is lifted up by the intermediate pressure pressure and is in close contact with the opposing member, thereby forming a back pressure chamber.

However, in the conventional scroll compressor as described above, the sealing member is brought into contact while floating toward the opposite member by the intermediate pressure, thereby exhibiting a high sealing effect in the axial direction. However, as the sealing member is formed in an annular shape, when the back pressure chamber is formed inside the sealing member, a gap between the outer circumferential surface of the sealing member and the outer wall surface of the annular groove, the back pressure chamber is formed outside the sealing member In this case, there is a problem in that the refrigerant leaks through the gap between the inner circumferential surface of the sealing member and the inner wall surface of the annular groove, so that the back pressure chamber cannot be effectively formed. This means that, in order for the sealing member to move in the axial direction, a radial distance is required between the inner or outer circumferential surface of the sealing member and the inner or outer wall surface of the corresponding annular groove, respectively, but the sealing member is an annular shape of a square cross-section. This is due to a structural limitation in which the sealing member cannot expand and contract in the radial direction as it is formed.

In addition, in the conventional scroll compressor, as the sealing member is formed in a rectangular cross-sectional shape, the weight of the sealing member as a whole increases, and the sealing member does not float quickly during initial operation, thereby delaying the formation of the back pressure chamber. In addition, if the axial thickness of the sealing member is thinned in consideration of this, not only the radial sealing area is reduced, but also the life of the sealing member may be shortened due to wear with the other member, and if the radial width of the sealing member is made thin , not only the sealing area in the axial direction is reduced, but also the area subjected to the lifting pressure relative to the weight is reduced, so that the lifting of the sealing member may be delayed.

In addition, in the conventional scroll compressor, as shown in Korean Patent Application Laid-Open No. 10-2008-0090009, a method of cutting the middle of the annular sealing member so that the sealing member opens slightly in the radial direction when it floats is also known. , in this case, there was a problem in that the pressure in the back pressure chamber could not be kept constant as much as the pressure leakage of the back pressure chamber was generated through the incision. As described above, when the pressure in the back pressure chamber is not constant, the behavior of the orbiting scroll becomes unstable, and the sealing force in the compression chamber between the orbiting scroll and the fixed scroll is lowered, which may increase the compression loss.

Korean Patent Publication No. 10-2008-0090009

It is an object of the present invention to provide a scroll compressor capable of securing high axial sealing force and radial sealing force by forming a sealing member in an annular shape while having a displacement in the radial direction.

Another object of the present invention is to provide a scroll compressor capable of forming a back pressure chamber in a short time by forming the sealing member in an annular shape while the sealing member rapidly floats.

Another object of the present invention is to provide a scroll compressor capable of securing the sealing area in radial and axial directions while reducing the weight of the sealing member and securing the thickness of the sealing member in preparation for wear.

Another object of the present invention is to provide a scroll compressor capable of stabilizing the behavior of the orbiting scroll by increasing the sealing effect of the sealing member and thereby preventing refrigerant leakage in the compression chamber in advance.

In order to achieve the object of the present invention, a sealing member is inserted into a groove formed in one of the two members that slide with each other and floats according to a pressure difference, and includes a sealing member sealing between the contact surfaces between the two members, A scroll compressor may be provided, wherein the sealing member is formed in an annular shape and has a 'L' cross-sectional shape, and an outer diameter of the sealing member is formed smaller than an outer diameter of an annular groove into which the sealing member is inserted. .

Here, the sealing member may be formed as a single body without a cutout.

Further, the 'ㅣ' part constitutes a radial sealing part in contact with the outer wall surface of the groove, and may be formed to be relatively thin compared to the '-' part forming an axial sealing part in contact with the thrust surface of the opposite member.

In order to achieve the object of the present invention, a first scroll; a second scroll forming a compression chamber together with the first scroll while rotating with respect to the first scroll; a frame coupled to the first scroll to support the second scroll; a sealing member insertion groove formed in an annular shape on at least one of one side of the second scroll or one side of the frame in contact with the second scroll; and a sealing member formed in an annular shape and inserted into the sealing member insertion groove and configured to radially separate a distance between the second scroll and the frame, wherein the sealing member has a cross-sectional area of an inner circumferential surface greater than a cross-sectional area of an outer circumferential surface is formed to be small, and a second interval between the outer circumferential surface of the sealing member and the outer wall surface of the sealing member insertion groove is smaller than or equal to the first interval between the inner circumferential surface of the sealing member and the inner wall surface of the sealing member insertion groove A scroll compressor characterized in that may be provided.

Here, the second interval may be formed to be 0.05 to 1.0% of the outer diameter of the sealing member.

A first chamfer may be formed on at least one of an outer edge of the sealing member insertion groove and an outer edge of the sealing member.

In addition, the sealing member has a first sealing part formed in an annular shape, one surface of which forms an axial sealing surface with the frame, and the other surface of the first sealing part extending in an annular shape so that the outer peripheral surface of the sealing member insertion groove is The second sealing portion may be formed to form an outer wall surface and a radial sealing surface, and an axial height of the first chamfer may be formed to be less than or equal to an axial thickness of the first sealing portion.

In addition, the sealing member has a first sealing part formed in an annular shape, one surface of which forms an axial sealing surface with the frame, and the other surface of the first sealing part extending in an annular shape so that the outer peripheral surface of the sealing member insertion groove is The second sealing portion may be formed to form an outer wall surface and a radial sealing surface, and an outer diameter of the first sealing portion and an outer diameter of the second sealing portion may be the same.

In addition, the sealing member has a first sealing part formed in an annular shape, one surface of which forms an axial sealing surface with the frame, and the other surface of the first sealing part extending in an annular shape so that the outer peripheral surface of the sealing member insertion groove is The second sealing part may be configured to form an outer wall surface and a radial sealing surface, and an outer diameter of the first sealing part may be different from an outer diameter of the second sealing part.

In addition, the second interval may be formed to be 0.05 to 1.0% of the outer diameter of the sealing member.

In addition, the sealing member may be formed of a material in which Teflon (PTFE) and carbon fiber are mixed.

And, the sealing member may further include a graphite material.

Here, the sealing member may be formed in a 'L'-shaped cross-sectional shape, and a portion in contact with the frame may be formed to be thicker than a portion in contact with the sealing member insertion groove.

Here, the gap between the second scroll and the frame is formed such that an inner gap in a radial direction with respect to the sealing member insertion groove is larger than an outer gap in a radial direction around the sealing member insertion groove, and the second scroll or the frame has the inner gap. A first passageway communicating between the gap and the outer gap may be formed.

A second passage for communicating the outer gap to the compression chamber may be formed in the first scroll or the frame.

In addition, in order to achieve the object of the present invention, a casing in which oil is stored in the inner space; a driving motor provided in the inner space of the casing; a rotating shaft coupled to the driving motor; a frame provided under the driving motor; a first scroll provided under the frame; A second scroll having a sealing member insertion groove formed on a surface in contact with the frame and provided between the frame and the first scroll, and the rotation shaft is eccentrically coupled to form a compression chamber between the first scroll and the first scroll while rotating. ; a sealing member formed in an annular shape and inserted into the sealing member insertion groove and provided between the frame and the second scroll to separate the interval between the frame and the second scroll into an inner interval and an outer interval; A scroll compressor may be provided, wherein the member has an inner circumferential cross-sectional area smaller than an outer circumferential cross-sectional area, and an outer diameter of the sealing member is smaller than an outer diameter of the sealing member insertion groove.

Here, a plurality of oil passages for guiding the oil stored in the casing to the outer circumferential surface of the rotation shaft are formed on the rotation shaft, and at least one oil flow passage among the plurality of oil passages communicates with the inner gap separated by the sealing member. can be formed.

In addition, the outer gap communicates with a compression chamber that forms an intermediate pressure between the suction pressure and the discharge pressure in the compression chamber, and a communication passage for communicating the inner gap and the outer gap is further formed in the second scroll or frame, , the communication passage may be provided with a pressure reducing unit.

In addition, the outer gap is formed to have a narrower gap between the frame and the second scroll than the inner gap, and a chamfer inclined in the direction of the sealing member inserting groove is formed at a corner of the sealing member insertion groove in contact with the outer gap. can

In addition, the sealing member is formed in a 'L'-shaped cross-sectional shape, the outer diameter may be formed smaller than the outer diameter of the sealing member insertion groove by 0.05 ~ 1.0%.

Here, the sealing member may be formed of a material in which Teflon (PTFE) and carbon fiber are mixed.

And, the sealing member may further include a graphite material.

In the scroll compressor according to the present invention, as the sealing member provided between the second scroll and the frame is formed in a single annular shape and is displaced in the radial direction by pressure, the axial sealing force of the sealing member as well as the radial direction By increasing the sealing force, it is possible to suppress the operation delay during starting in advance.

In addition, by optimizing the distance between the outer peripheral surface of the sealing member and the corresponding sealing member insertion groove, it is possible to secure the radial sealing force while preventing the sealing member from excessively adhering to the sealing member insertion groove. It can float quickly so that the back pressure chamber can be formed in a short time.

In addition, as the sealing effect of the sealing member is increased, the pressure in the back pressure chamber is maintained at a constant pressure, and through this, the behavior of the orbiting scroll is stabilized and refrigerant leakage in the compression chamber is suppressed, and the compression efficiency can be improved.

In addition, since no cutout is provided in the sealing member, it is possible to prevent the sealing member from being damaged when applied to a high compression ratio compressor, thereby improving reliability.

In addition, as the sealing member is composed of the first sealing portion and the second sealing portion and the second sealing portion is formed thinner than the first sealing portion, the weight of the sealing member is reduced, and thus the sealing member is quickly floated even during initial start-up. Thus, compression efficiency may be improved.

In addition, the thickness of the first sealing part is formed thick to prevent shortening of life due to wear, and the thickness of the second sealing part is formed thin so that the second sealing part can be bent quickly even at the initial start-up to form a radial sealing part. have.

1 is a longitudinal cross-sectional view showing a lower compression type scroll compressor according to the present invention;
2 is a cross-sectional view showing the compression part in FIG. 1;
Figure 3 is a front view showing a part of the rotation shaft to explain the sliding part in Figure 1,
4 is a longitudinal sectional view showing the oil supply passage between the back pressure chamber and the compression chamber in FIG. 1;
5 is a perspective view showing the sealing member in FIG. 1 disassembled from the scroll;
6 is a plan view showing a state in which the sealing member according to FIG. 5 is inserted into the sealing member insertion groove;
7 is a front sectional view "V-V" of FIG.
8A is a graph showing the rate of change of the pressure ratio with respect to the operating time during normal operation in the scroll compressor to which the sealing member is applied according to the present embodiment, and FIG. 8B is a graph showing the rate of change of the pressure ratio with respect to the operating time when the operation is delayed;
9 is a graph showing the change rate of the pressure ratio according to the ratio (%) of the radial spacing of the sealing member to the outer diameter of the sealing member insertion groove in the scroll compressor to which the sealing member is applied according to the present embodiment;
10 is a schematic diagram showing the specification of the sealing member according to the present embodiment;
11 is a longitudinal cross-sectional view showing an embodiment of the snagging prevention part of the sealing member according to the present embodiment;
12 is a longitudinal cross-sectional view showing an embodiment of the oil guide part of the sealing member insertion groove according to the present embodiment;
13A and 13B are longitudinal cross-sectional views showing a compressor stop state and an operating state with respect to the sealing member according to the present embodiment;
14 and 15 are schematic views showing other embodiments of the sealing member according to the present embodiment;
16 and 17 are longitudinal cross-sectional views showing still other embodiments of the sealing member according to the present invention;
18 is a longitudinal cross-sectional view showing another embodiment for levitating a sealing member in the scroll compressor according to the present invention;

Hereinafter, a scroll compressor according to the present invention will be described in detail based on an embodiment shown in the accompanying drawings. For reference, the scroll compressor according to the present invention relates to a structure for increasing the sealing force and durability of a sealing member that is installed between an orbiting scroll and a frame corresponding thereto to form a back pressure chamber. Therefore, the scroll compressor having the sealing member between the orbiting scroll and the contacting member can be applied to any type of scroll compressor. However, hereinafter, for convenience, in a lower compression type scroll compressor in which the compression part is located below the electric part, a scroll compressor of a type in which the rotation shaft overlaps on the same plane as the orbiting wrap will be described as a representative example. This type of scroll compressor is known to be suitable for application to a refrigeration cycle under high-temperature and high-compression ratio conditions.

1 is a longitudinal cross-sectional view showing a lower compression type scroll compressor according to the present invention, FIG. 2 is a cross-sectional view showing the compression part in FIG. 1, and FIG. 3 is a front view showing a part of the rotating shaft to explain the sliding part in FIG. FIG. 4 is a longitudinal cross-sectional view illustrating the oil supply passage between the back pressure chamber and the compression chamber in FIG. 1 .

Referring to FIG. 1 , in the lower compression scroll compressor according to the present embodiment, an electric part 20 that forms a driving motor and generates a rotational force is installed inside the casing 10 , and the lower side of the electric part 20 is A compression unit 30 for compressing the refrigerant by receiving the rotational force of the electric part 20 with a predetermined space (hereinafter, referred to as an intermediate space) 10a may be installed.

The casing 10 includes a cylindrical shell 11 constituting an airtight container, an upper shell 12 that covers the upper portion of the cylindrical shell 11 to form an airtight container, and a lower portion of the cylindrical shell 11 to form an airtight container together. At the same time, it may be formed of a lower shell 13 forming a storage space 10c.

The refrigerant suction pipe 15 penetrates through the side of the cylindrical shell 11 to directly communicate with the suction chamber of the compression unit 30, and the upper portion of the upper shell 12 communicates with the upper space 10b of the casing 10 A refrigerant discharge pipe 16 may be installed. The refrigerant discharge pipe 16 corresponds to a passage through which the compressed refrigerant discharged from the compression unit 30 to the upper space 10b of the casing 10 is discharged to the outside, and the upper space 10b is a kind of oil separation space. The refrigerant discharge pipe 16 may be inserted to the middle of the upper space 10b of the casing 10 so as to be formed. And in some cases, an oil separator (not shown) that separates oil mixed with the refrigerant is installed in the inside of the casing 10 including the upper space 10b or in the upper space 10b by connecting to the refrigerant suction pipe 16. can be

The stator 21 has teeth and slots forming a plurality of coil winding portions (unsigned) along the circumferential direction on its inner circumferential surface, so that the coil 25 is wound, and between the inner circumferential surface of the stator and the outer circumferential surface of the rotor 22 . _{A second refrigerant passage P G2} is formed by combining the gap and the coil winding portion. Accordingly, the refrigerant discharged to the intermediate space 10c between the transmission unit 20 and the compression unit 30 through the first refrigerant passage P _{G1 to be described later is a second refrigerant passage formed in the transmission unit 20 (} P _G2 ) is moved to the upper space (10b) formed on the upper side of the transmission unit (20).

And a plurality of decut (D-cut) surfaces 21a are formed on the outer peripheral surface of the stator 21 in the circumferential direction, and the decut surfaces 21a are formed so that oil passes between the inner peripheral surface of the cylindrical shell 11 and the inner peripheral surface of the cylindrical shell 11. One oil passage P _O1 may be formed. Accordingly, the oil separated from the refrigerant in the upper space 10b moves to the lower space 10c through _{the first oil passage P O1} and the second oil passage P _{O2 to be described later.}

On the lower side of the stator 21 , a frame 31 constituting the compression part 30 at a predetermined interval may be fixedly coupled to the inner circumferential surface of the casing 10 . The frame 31 may be fixedly coupled to the outer circumferential surface by shrink-fitting or welding the outer circumferential surface to the inner circumferential surface of the cylindrical shell 11 .

And an annular frame side wall part (first side wall part) 311 is formed at the edge of the frame 31, and a plurality of communication grooves 311b are formed on the outer peripheral surface of the first side wall part 311 along the circumferential direction. can be The communication groove 311b forms _{a second oil passage P O2} together with the communication groove 322b of the first scroll 32 to be described later.

In addition, a first bearing portion 312 for supporting the main bearing portion 51 of the rotation shaft 50 to be described later is formed in the center of the frame 31 , and the main bearing portion of the rotation shaft 50 is formed in the first bearing portion. The first bearing hole 312a may be formed through in the axial direction so that the 51 is rotatably inserted and supported in the radial direction.

In addition, a fixed scroll (hereinafter, referred to as a first scroll) 32 may be installed on a lower surface of the frame 31 with an orbiting scroll (hereinafter, referred to as a second scroll) 33 eccentrically coupled to the rotating shaft 50 therebetween. The first scroll 32 may be fixedly coupled to the frame 31 , or may be coupled to be movable in the axial direction.

Meanwhile, in the first scroll 32 , a fixed end plate portion (hereinafter, referred to as a first end plate portion) 321 is formed in a substantially disk shape, and the edge of the first end plate portion 321 is coupled to the lower surface edge of the frame 31 . A scroll sidewall portion (hereinafter, referred to as a second sidewall portion) 322 may be formed.

A suction port 324 through which the refrigerant suction pipe 15 and the suction chamber communicate is formed through one side of the second side wall portion 322, and the central portion of the first end plate portion 321 communicates with the discharge chamber to discharge the compressed refrigerant. Discharge holes 325a and 325b may be formed. Only one discharge port 325a and 325b may be formed to communicate with both the first and second compression chambers V1 and V2, which will be described later, but are independent of each of the compression chambers V1 and V2. A plurality may be formed to communicate with the .

And the communication groove 322b described above is formed on the outer circumferential surface of the second side wall portion 322, and the communication groove 322b is the communication groove 311b of the first side wall portion 311 and the oil recovered together with the lower space. _{A second oil passage P O2} for guiding to (10c) is formed.

Also, a discharge cover 34 for guiding the refrigerant discharged from the compression chamber V to a refrigerant passage to be described later may be coupled to the lower side of the first scroll 32 . The discharge cover 34 has an inner space that accommodates the discharge ports 325a and 325b, and at the same time receives the refrigerant discharged from the compression chamber V through the discharge ports 325a and 325b in the upper space of the casing 10 ( 10b), more precisely, it may be formed to accommodate the inlet of _{the first refrigerant passage P G1} guiding into the space between the transmission unit 20 and the compression unit 30 .

Here, the first refrigerant flow path ( _PG1 ) is the inside of the flow path separation unit 40, that is, the second side wall portion 322 of the fixed scroll 32 on the inner side of the flow path separation unit 40 from the side of the rotation shaft 50 side. and the first sidewall portion 311 of the frame 31 may be sequentially formed. Accordingly, on the outside of the flow path separation unit 40 , the above-described second oil flow path P _O2 is formed to communicate with the first oil flow _{path P O1 .}

And on the upper surface of the first end plate portion 321, a fixed wrap (hereinafter, referred to as a first wrap) 323 may be formed in engagement with a turning wrap (hereinafter, referred to as a second wrap) 33 to be described later to form a compression chamber V. have. The first wrap 323 will be described later along with the second wrap 332 .

In addition, a second bearing part 326 for supporting a sub-bearing part 52 of the rotation shaft 50 to be described later is formed in the center of the first head plate part 321 , and the second bearing part 326 is provided in the axial direction. A second bearing hole 326a may be formed therethrough to support the sub-bearing part 52 in a radial direction.

Meanwhile, in the second scroll 33 , the orbiting end plate portion (hereinafter, referred to as the second end plate portion) 331 may be formed in a substantially disk shape. A second wrap 332 may be formed on a lower surface of the second end plate 331 to be engaged with the first wrap 322 to form a compression chamber.

The second wrap 332 may be formed in an involute shape together with the first wrap 323 , but may be formed in various other shapes. For example, as shown in FIG. 2 , the second wrap 332 has a shape in which a plurality of arcs having different diameters and origins are connected, and the outermost curve may be formed in an approximately elliptical shape having a major axis and a minor axis. . The first wrap 323 may likewise be formed.

In the central portion of the second end plate 331, the inner end of the second wrap 332 is formed, and an eccentric portion 53 of the rotation shaft 50, which will be described later, is rotatably inserted and coupled to the rotation shaft coupling portion 333. direction may be formed through.

The outer periphery of the rotation shaft coupling part 333 is connected to the second wrap 332 to form a compression chamber V together with the first wrap 322 in the compression process.

In addition, the rotation shaft coupling portion 333 is formed to have a height overlapping with the second wrap 332 on the same plane, so that the eccentric portion 53 of the rotation shaft 50 overlaps with the second wrap 332 on the same plane. can be placed in Through this, the repulsive force and the compressive force of the refrigerant are applied to the same plane with respect to the second end plate and cancel each other out, so that the inclination of the second scroll 33 due to the action of the compressive force and the repulsive force can be prevented.

In addition, the rotation shaft coupling portion 333 has a concave portion 335 engaged with the protrusion 328 of the first wrap 323 to be described later is formed on an outer peripheral portion opposite to the inner end of the first wrap 323 . One side of the concave portion 335 is formed with an increasing portion 335a increasing in thickness from the inner periphery to the outer periphery of the rotary shaft coupling portion 333 on the upstream side along the formation direction of the compression chamber V. This lengthens the compression path of the first compression chamber V1 just before discharge, and consequently makes it possible to increase the compression ratio of the first compression chamber V1 close to the pressure ratio of the second compression chamber V2. The first compression chamber V1 is a compression chamber formed between the inner surface of the first wrap 323 and the outer surface of the second wrap 332 , and will be described later separately from the second compression chamber V2 .

The other side of the concave portion 335 is formed with an arc compression surface (335b) having an arc shape. The diameter of the arc compression surface 335b is determined by the inner end thickness (ie, the thickness of the discharge end) of the first wrap 323 and the turning radius of the second wrap 332 , the inner side of the first wrap 323 . When the end thickness is increased, the diameter of the arc compression surface 335b is increased. Due to this, the thickness of the second wrap around the arc compression surface 335b may also be increased to ensure durability, and the compression path may be lengthened so that the compression ratio of the second compression chamber V2 may be increased accordingly.

In addition, in the vicinity of the inner end (suction end or start end) of the first wrap 323 corresponding to the rotation shaft coupling portion 333, a projection 328 protruding toward the outer periphery of the rotation shaft coupling portion 333 is formed, the projection ( A contact portion 328a that protrudes from the protrusion and engages with the concave portion 335 may be formed in the 328 . That is, the inner end of the first wrap 323 may be formed to have a greater thickness than other portions. Due to this, the lap strength of the inner end that receives the greatest compressive force among the first laps 323 may be improved, and thus durability may be improved.

Meanwhile, the compression chamber V is formed between the first end plate portion 321 and the first wrap 323 , and between the second wrap 332 and the second end plate portion 331 , and is sucked along the moving direction of the wrap. The chamber, the intermediate pressure chamber, and the discharge chamber may be continuously formed.

As shown in FIG. 2 , the compression chamber V includes a first compression chamber V1 formed between the inner surface of the first wrap 323 and the outer surface of the second wrap 332 , and the first wrap 323 . The second compression chamber V2 formed between the outer surface and the inner surface of the second wrap 332 may be formed.

That is, the first compression chamber (V1) includes a compression chamber formed between the two contact points (P11, P12) formed by contacting the inner surface of the first wrap 323 and the outer surface of the second wrap 332, and , the second compression chamber (V2) includes a compression chamber formed between the two contact points (P21, P22) generated by the contact between the outer surface of the first wrap 323 and the inner surface of the second wrap (332).

Here, the first compression chamber (V1) just before the discharge is the center of the eccentric, that is, the center of the rotation shaft coupling portion (O) and the two lines connecting the two contact points (P11, P12), respectively, the angle having a larger value among the angles When α is α, α < 360° at least immediately before the start of discharge, and the distance ℓ between the normal vectors at the two contact points P11 and P12 also has a value greater than 0.

Due to this, since the first compression chamber immediately before discharge has a smaller volume compared to the case in which the fixed lap and the orbital lap made of the involute curve have a smaller volume, the sizes of the first lap 323 and the second lap 332 are not increased. Both the compression ratio of the first compression chamber V1 and the compression ratio of the second compression chamber V2 may be improved without the need to do so.

Meanwhile, as described above, the second scroll 33 may be pivotably installed between the frame 31 and the fixed scroll 32 . An Oldham ring 35 for preventing rotation of the second scroll 33 is installed between the upper surface of the second scroll 33 and the lower surface of the frame 31 corresponding thereto. A sealing member 36 forming the back pressure chamber S1 to be performed may be installed.

In addition, an intermediate pressure space is formed outside the sealing member 36 by the oil supply hole 321a provided in the second scroll 32 . This intermediate pressure space communicates with the intermediate compression chamber V and may serve as a back pressure chamber as the intermediate pressure refrigerant is filled. Accordingly, the back pressure chamber formed inside the sealing member 36 as the center may be referred to as a first back pressure chamber S1 , and the intermediate pressure space formed outside the sealing member 36 may be referred to as a second back pressure chamber S2 . After all, the back pressure chamber S1 is a space formed by the lower surface of the frame 31 and the upper surface of the second scroll 33 with the sealing member 36 as the center. will be explained again with

On the other hand, the flow path separation unit 40 is installed in the intermediate space 10a, which is a gas oil space formed between the lower surface of the transmission unit 20 and the upper surface of the compression unit 30, the refrigerant discharged from the compression unit 30 is It serves to prevent interference with the oil moving from the upper space 10b of the electric part 20, which is the oil separation space, to the lower space 10c of the compression part 30, which is the storage space.

To this end, the flow path separation unit 40 according to the present embodiment separates the first space 10a into a space in which the refrigerant flows (hereinafter referred to as a refrigerant flow space) and a space through which oil flows (hereinafter, an oil flow space). Euro guide included. The flow guide may separate the first space 10a into a refrigerant flow space and an oil flow space with only the flow guide itself, but in some cases, a plurality of flow guides may be combined to serve as a flow guide.

The flow path separation unit according to the present embodiment includes a first flow path guide 410 provided on the frame 31 and extending upward, and a second flow path guide 420 provided on the stator 21 and extending downward. The first flow guide 410 and the second flow guide 420 overlap in the axial direction so that the intermediate space 10a can be separated into a refrigerant flow space and an oil flow space.

Here, the first flow guide 410 is manufactured in an annular shape and fixedly coupled to the upper surface of the frame 31 , and the second flow guide 420 is inserted into the stator 21 to extend from the insulator to insulate the winding coil. can

The first flow guide 410 includes a first round wall part 411 extending upward from the outside, a second round wall part 412 extending upward from the inside, and a first round wall part 411 and a second round wall part 412 ) consists of a circular surface portion 413 extending in the radial direction to connect between. The first round wall portion 411 is formed higher than the second round wall portion 412, and the refrigerant hole is formed in the round surface portion 413 so that the refrigerant hole communicating from the compression unit 30 to the intermediate space 10a communicates. can

And, the balance weight 26 is located inside the second round wall portion 412, that is, in the direction of the rotation axis, the balance weight 26 is coupled to the rotor 22 or the rotation shaft 50 and rotates. At this time, the balance weight 26 can stir the refrigerant while rotating, but it prevents the refrigerant from moving toward the balance weight 26 by the second round wall 412 so that the refrigerant is stirred by the balance weight 26 can be suppressed

The second flow guide 420 may include a first extension portion 421 extending downwardly from the outside of the insulator and a second extension portion 422 extending downwardly from the inside of the insulator. The first extension portion 421 is formed to overlap the first round wall portion 411 in the axial direction, and serves to separate the refrigerant flow space and the oil flow space. The second extension 422 may not be formed as needed, but even if it is formed, it does not overlap with the second round wall 412 in the axial direction or is formed at a sufficient distance in the radial direction so that the refrigerant can sufficiently flow even if it overlaps. It is preferable to be

On the other hand, the upper portion of the rotation shaft 50 is coupled to the center of the rotor 22, while the lower portion is coupled to the compression unit 30 may be supported in the radial direction. As a result, the rotation shaft 50 transmits the rotational force of the transmission unit 20 to the orbiting scroll 33 of the compression unit 30 . Then, the second scroll 33 eccentrically coupled to the rotation shaft 50 rotates with respect to the first scroll 32 .

A main bearing part (hereinafter, the first bearing part) 51 is formed in the lower half of the rotation shaft 50 so as to be inserted into the first bearing hole 312a of the frame 31 and supported in the radial direction, and the first bearing part ( A sub-bearing part (hereinafter, referred to as a second bearing part) 52 may be formed at a lower side of the first scroll 32 to be inserted into the second bearing hole 326a of the first scroll 32 and supported in the radial direction. And an eccentric part 53 may be formed between the first bearing part 51 and the second bearing part 52 to be inserted into and coupled to the rotation shaft coupling part 333 .

The first bearing part 51 and the second bearing part 52 are formed on a coaxial line to have the same axial center, and the eccentric part 53 is attached to the first bearing part 51 or the second bearing part 52 . It may be formed eccentric in the radial direction with respect to the. The second bearing part 52 may be formed to be eccentric with respect to the first bearing part 51 .

The eccentric part 53 must be formed to have an outer diameter smaller than the outer diameter of the first bearing part 51 and larger than the outer diameter of the second bearing part 52 so that the rotating shaft 50 is connected to each of the bearing holes 312a and 326a. It may be advantageous for coupling through the rotation shaft coupling portion 333 . However, when the eccentric portion 53 is not integrally formed with the rotation shaft 50 and is formed using a separate bearing, the outer diameter of the second bearing portion 52 is not formed smaller than the outer diameter of the eccentric portion 53 . It can be coupled by inserting the rotation shaft (50).

In addition, an oil supply passage 50a for supplying oil to each bearing portion and the eccentric portion may be formed in the rotation shaft 50 along the axial direction. The oil supply passage 50a is approximately at the lower end or intermediate height of the stator 21 from the lower end of the rotary shaft 50 as the compression unit 30 is located below the transmission unit 20, or the first bearing unit 31 It can be formed by a groove digging to a position higher than the top of the . Of course, in some cases, it may be formed to pass through the rotation shaft 50 in the axial direction.

In addition, an oil feeder 60 for pumping oil filled in the lower space 10c may be coupled to a lower end of the rotation shaft 50 , that is, a lower end of the second bearing unit 52 . The oil feeder 60 is composed of an oil supply pipe 61 inserted into and coupled to the oil supply passage 50a of the rotating shaft 50, and a blocking member 62 that accommodates the oil supply pipe 61 and blocks the intrusion of foreign substances. can The oil supply pipe 61 may pass through the discharge cover 34 and be positioned so as to be submerged in the oil of the lower space 10c.

On the other hand, as shown in Fig. 3, each of the bearing parts 51 and 52 and the eccentric part 53 of the rotating shaft 50 is connected to the oil supply passage 50a to supply oil to each sliding part. A channel F1 is formed.

The sliding part oil supply passage F1 includes a plurality of oil supply holes 511, 521 and 531 that penetrate from the oil supply passage 50a toward the outer circumferential surface of the rotary shaft 50, and each bearing portion 51 and 52. and a plurality of oil supply grooves 512 (512) ( 522) and 532.

For example, the first bearing part 51 has a first oil supply hole 511 and a first oil supply groove 512 , and the second bearing part 52 has a second oil supply hole 521 and a second oil supply groove ( 522, and the eccentric portion 53 is formed with a third oil supply hole 531 and a third oil supply groove 532, respectively. The first oil supply groove 512, the second oil supply groove 522, and the third oil supply groove 532 are each formed in a long groove shape in an axial direction or an oblique direction.

And, between the first bearing part 51 and the eccentric part 53, and between the eccentric part 53 and the second bearing part 52, the first connecting groove 541 and the second connecting groove each having an annular shape. 542 are respectively formed. The first connection groove 541 is connected to the lower end of the first oil supply groove 512 , and the second connection groove 542 is connected to the upper end of the second oil supply groove 522 . Accordingly, a portion of the oil lubricating the first bearing part 51 through the first oil supply groove 512 flows down to the first connection groove 541 and is collected, and this oil is transferred to the first back pressure chamber S1. It flows in to form a back pressure of the discharge pressure. In addition, the oil lubricating the second bearing portion 52 through the second oil supply groove 522 and the oil lubricating the eccentric portion 53 through the third oil supply groove 532 are connected to the second connection groove 542 . They may be gathered and introduced into the compression unit 30 through the front end surface of the rotation shaft coupling unit 333 and the first end plate 321 .

And a small amount of oil sucked in the upper end direction of the first bearing unit 51 flows out of the bearing surface from the upper end of the first bearing unit 312 of the frame 31 and flows along the first bearing unit 312 along the frame 31 _{After flowing down to the upper surface 31a of ), the oil passage P O1} continuously formed on the outer peripheral surface of the frame 31 (or a groove communicating from the upper surface to the outer peripheral surface) and the outer peripheral surface of the first scroll 32 ) (P O1 ) (P _O2 ) through the lower space (10c) is recovered.

In addition, oil discharged from the compression chamber (V) to the upper space (10b) of the casing (10) together with the refrigerant is separated from the refrigerant in the upper space (10b) of the casing (10), on the outer peripheral surface of the electric part (20) It is recovered to the lower space 10c through the formed first oil passage P _{O1 and the second oil passage P O2} formed on the outer peripheral surface of the compression unit 30 . At this time, the flow path separation unit 40 is provided between the electric part 20 and the compression part 30, and the oil separated from the refrigerant in the upper space 10b and moved to the heart space 10c is transferred to the compression part 20 ) and does not interfere with the refrigerant moving to the upper space 10b and do not _remix , and each oil flows through different passages [(P O1 )(P _O2 )][(P _G1 )(P _G2 )] into the lower space At (10c), the refrigerant can move to the upper space (10b).

On the other hand, the compression chamber oil supply passage F2 for supplying the oil sucked through the oil supply passage 50a to the compression chamber V is formed in the second scroll 33 . The compression chamber oil supply passage (F2) is connected to the sliding part oil supply passage (F1) described above.

The compression chamber oil supply passage F2 includes a first oil supply passage 371 communicating between the oil supply passage 50a and a second back pressure chamber S2 forming an intermediate pressure space, a second back pressure chamber S2 and It may be made of a second oil supply passage 372 communicating with the intermediate pressure chamber of the compression chamber (V).

Of course, the compression chamber oil supply passage may be formed to directly communicate with the intermediate pressure chamber from the oil supply passage 50a without passing through the second back pressure chamber S2. However, in this case, a refrigerant flow path connecting the second back pressure chamber S2 and the intermediate pressure chamber V must be separately provided, and for supplying oil to the Oldham ring 35 located in the second back pressure chamber S2. A separate oil path must be provided. As a result, the number of passages increases and processing becomes complicated. Therefore, in order to reduce the number of passages by unifying the refrigerant passage and the oil passage, as in the present embodiment, the oil supply passage 50a and the second back pressure chamber S2 are communicated, and the second back pressure chamber S2 is connected to the intermediate pressure chamber. It may be desirable to communicate with (V).

To this end, in the first oil supply passage 371 , a first turning passage portion 371a formed from the lower surface of the second end plate 331 to the middle in the thickness direction is formed, and in the first turning passage portion 371a A second turning passage part 371b is formed toward the outer circumferential surface of the second head plate part 331 , and a third turning passage part penetrating from the second turning passage part 371b toward the upper surface of the second end plate part 331 . (371c) is formed.

Further, the first turning passage portion 371a is formed at a position belonging to the first back pressure chamber S1 , and the third turning passage portion 371c is formed at a position belonging to the second back pressure chamber S2 . And a pressure reducing rod 375 in the second turning passage part 371b to lower the pressure of oil moving from the first back pressure chamber S1 to the second back pressure chamber S2 through the first oil supply passage 371 ) is inserted. Accordingly, the cross-sectional area of the second turning passage part 371b excluding the pressure reducing rod 375 is formed to be small in the first turning passage part 371a, the third turning passage part 371c, and the second turning passage part 371b.

Here, when the end of the third revolving passage portion 371c is formed to be located inside the Oldham ring 35, that is, between the Oldham ring 35 and the sealing member 36, the first oil supply passage 371 ), the oil moving through the Oldham ring 35 is clogged and cannot smoothly move to the second back pressure chamber S2. Accordingly, in this case, the fourth turning passage part 371d may be formed from the end of the third turning passage part 371c toward the outer peripheral surface of the second end plate part 331 . The fourth turning passage part 371d may be formed as a groove on the upper surface of the second end plate part 331 as shown in FIG. 4 , or may be formed as a hole inside the second end plate part 331 .

The second oil supply passage 372 has a first fixed passage portion 372a formed on the upper surface of the second side wall portion 322 in the thickness direction, and a second fixed passage in the radial direction from the first fixed passage portion 372a. A portion 372b is formed, and a third fixed passage portion 372c that communicates from the second fixed passage portion 372b to the intermediate pressure chamber V is formed.

In the drawings, an unexplained reference numeral 70 denotes an accumulator.

The lower compression type scroll compressor according to the present embodiment as described above operates as follows.

That is, when power is applied to the electric part 20, rotational force is generated in the rotor 21 and the rotating shaft 50 to rotate, and as the rotating shaft 50 rotates, the orbiting scroll eccentrically coupled to the rotating shaft 50 (33) is rotated by the Oldham ring (35).

Then, the refrigerant supplied from the outside of the casing 10 through the refrigerant suction pipe 15 flows into the compression chamber V, and the volume of the compression chamber V is reduced by the orbiting scroll 33's orbiting motion. As it decreases, it is compressed and discharged into the inner space of the discharge cover 34 through the discharge ports 325a and 325b.

Then, the refrigerant discharged into the inner space of the discharge cover 34 circulates in the inner space of the discharge cover 34, and after the noise is reduced, it moves to the space between the frame 31 and the stator 21, and this refrigerant is moved to the upper space of the electric part 20 through the gap between the stator 21 and the rotor 22 .

Then, after the oil is separated from the refrigerant in the upper space of the electric part 20, the refrigerant is discharged to the outside of the casing 10 through the refrigerant discharge pipe 16, while the oil is separated from the inner circumferential surface of the casing 10 and the stator ( 21) through the flow path and the flow path between the inner circumferential surface of the casing 10 and the outer circumferential surface of the compression part 30, a series of processes of recovery to the lower space 10c, which is the oil storage space of the casing 10, are repeated.

At this time, the oil in the lower space 10c is sucked through the oil supply passage 50a of the rotary shaft 50, and this oil is supplied through each oil supply hole 511, 521, 531 and oil supply groove 512, 522. ) 532 to lubricate the first bearing part 51 , the second bearing part 52 , and the eccentric part 53 , respectively.

Among them, the oil lubricating the first bearing part 51 through the first oil supply hole 511 and the first oil supply groove 512 is a first connection groove between the first bearing part 51 and the eccentric part 53 . 541, and this oil flows into the first back pressure chamber S1. This oil almost forms a discharge pressure, so that the pressure in the first back pressure chamber S1 also almost forms a discharge pressure. Accordingly, the central portion of the second scroll 33 can be supported in the axial direction by the discharge pressure.

Meanwhile, the oil in the first back pressure chamber S1 moves to the second back pressure chamber S2 through the first oil supply passage 371 due to the pressure difference with the second back pressure chamber S2 . At this time, a pressure reducing rod 375 is provided in the second swirl passage portion 371b constituting the first oil supply passage 371 , and the pressure of oil directed to the second back pressure chamber S2 is reduced to an intermediate pressure.

And, the oil moving to the second back pressure chamber (intermediate pressure space) S2 supports the edge of the second scroll 33 and at the same time, according to the pressure difference with the intermediate pressure chamber V, the second oil supply passage 372 is moved to the intermediate pressure chamber (V). However, when the pressure in the intermediate pressure chamber V becomes higher than the pressure in the second back pressure chamber S2 during the operation of the compressor, the refrigerant flows into the second back pressure chamber S2 through the second oil supply passage 372 in the intermediate pressure chamber V. ) will move towards In other words, the second oil supply passage 372 serves as a passage through which the refrigerant and the oil cross move according to the pressure difference between the pressure in the second back pressure chamber S2 and the intermediate pressure chamber V.

Meanwhile, as described above, a back pressure chamber is formed on the rear surface of the second scroll, that is, the upper surface of the second scroll, to prevent the second scroll from being pushed away from the first scroll by the pressure of the compression chamber.

That is, the back pressure chamber is provided with a sealing member on the lower surface of the frame and the upper surface of the second scroll, and the first back pressure chamber is formed between the second scroll and the frame, and the second back pressure chamber is formed between the second scroll and the frame and the first scroll, respectively. is formed

Accordingly, it is preferable that the sealing member has excellent sealing force between the frame and the second scroll, and has excellent wear resistance in consideration of friction caused by the revolving motion of the second scroll. In addition, since the sealing member seals in the axial direction while floating by pressure while being inserted into the sealing member insertion groove provided in the second scroll, it is preferable to be formed of a material and structure that can float quickly even at low pressure.

5 is an exploded perspective view of the sealing member according to the present embodiment, FIG. 6 is a plan view showing a state in which the sealing member according to FIG. 5 is inserted into the sealing member insertion groove, and FIG. 7 is "V-V" in FIG. “It is a cross-sectional view.

As shown in these drawings, the sealing member 36 according to the present embodiment may be formed in an annular shape with no cutout in the middle. And it is preferable that the sealing member 36 is made of a material that is light and can be bent according to pressure, such as Teflon.

Here, the sealing member 36 is formed in an annular shape, the upper surface of which is in contact with the lower surface of the frame 31 to form an axial sealing surface, and a first sealing part 361 and the lower edge of the first sealing part 361. It may be formed of a second sealing portion 362 extending downward in an annular shape, the outer peripheral surface of which is in contact with the outer wall surface of the sealing member insertion groove 336 to form a radial sealing surface.

As the first sealing part 361 is formed in a '-' cross-sectional shape, and the second sealing part 362 is formed in a 'ㅣ' cross-sectional shape at the lower surface edge of the first sealing part 361, the sealing member 36 ) may be formed as a whole in a 'a' cross-sectional shape. Accordingly, the first sealing part 361 has an end opposite to the end from which the second sealing part 362 extends, that is, the inner circumferential surface 36a forms a free end, and the second sealing part 362 has the first sealing part ( The end opposite to the end extending from 361, that is, the lower end 362a forms a free end. Accordingly, the second sealing part 362 is in close contact with the outer wall surface 336b of the sealing member insertion groove 336 while the periphery of the lower end 362a forming the free end is bent outward according to the pressure of the sealing member insertion groove 336. to form a radial sealing portion.

And, as in FIGS. 6 and 7 , the inner diameter D1 of the sealing member (precisely, the first sealing part) 36 is greater than the inner diameter D2 of the sealing member insertion groove 336 at the first interval (G1). The outer diameter D3 of the sealing member (precisely, the second sealing part) 36 may be formed smaller than the outer diameter D4 of the sealing member insertion groove 336 by the second interval G2.

Accordingly, the high-pressure fluid (refrigerant and oil) inside the sealing member 36 is formed between the inner wall surface 336a of the sealing member insertion groove 336 and the inner circumferential surface 36a of the sealing member 36, the first gap G1 ) through the sealing member insertion groove 336, the sealing member 36 may float by the pressure of this fluid. In addition, as the second gap G2 is formed between the outer wall surface 336b of the sealing member insertion groove 336 and the outer circumferential surface 36b of the sealing member 36, the sealing member 36 is inserted into the sealing member insertion groove ( 336) and can be quickly floated by non-contact or sliding contact.

On the other hand, as the sealing member 36 according to the present embodiment is formed in an annular shape, the inner circumferential surface 36a and the outer circumferential surface 36b of the sealing member 36 are the inner wall surface 336a and the outer side surface of the sealing member insertion groove 336 . The movement in the vertical direction is limited by the sizes of the gaps formed with the wall surface 336b, that is, the first gap G1 and the second gap G2.

That is, when the first gap G1 and the second gap G2 are too small, the inner circumferential surface 36a and the outer circumferential surface 36b of the sealing member 36 are in contact with the sealing member insertion groove 336 to prevent them from floating smoothly. can be In particular, in the sealing member 36 according to this embodiment, the second sealing part 362 is opened outward by the high-pressure oil flowing toward the first gap G1, and the outer wall surface of the sealing member insertion groove 336 ( 336b) and acts as a seal. Therefore, when the second gap G2 is formed too small, the second sealing part 362 is excessively closely attached to the outer wall surface 336b of the sealing member insertion groove 336, and the lifting of the sealing member 36 is delayed or worn. The outer peripheral surface 36b of the sealing member 36 may be sandwiched between the frame 31 and the second scroll 33 . Of course, if the second gap G2 is too large, a sufficient sealing area cannot be secured between the outer peripheral surface 36b of the second sealing part 362 and the outer wall surface 336b of the sealing member insertion groove 336, resulting in refrigerant leakage. can be

In view of this, in this embodiment, the sealing member 36 effectively suppresses the leakage of the refrigerant by having an appropriate range of the first interval G1 and the second interval G2, and the operation is performed smoothly and quickly. want to be able to

For example, as in FIGS. 6 and 7 , in the sealing member 36 according to the present embodiment, the first gap G1 is formed to be larger than the second gap G2, and the second gap G2 is the sealing member 36 . It may be preferable to be formed to be 0.05 to 1.0% with respect to the outer diameter D3 of the member 36 .

This can be confirmed through the graphs shown in FIGS. 8A to 9 . 8A is a graph showing the rate of change of the pressure ratio with respect to the operating time during normal operation, and FIG. 8B is a graph showing the rate of change of the pressure ratio with respect to the operating time when the operation is delayed.

That is, looking at the pressure ratio of the discharge pressure to the suction pressure (hereinafter referred to as the discharge pressure ratio) (Pd/Ps), in FIG. 8A , as the sealing member 36 operates normally, the discharge pressure ratio reaches a preset pressure after a certain period of time after starting. On the other hand, in FIG. 8B , as the sealing member 36 does not operate normally, the discharge pressure ratio rises up to the preset pressure vicinity, but it cannot be maintained and falls rapidly.

Also, looking at the pressure ratio of the intermediate pressure to the suction pressure (hereinafter referred to as the intermediate pressure ratio) (Pm/Ps), in FIG. 8A, the intermediate pressure ratio rises constantly during startup and is maintained for the operating time, whereas in FIG. 8B, it is excessively It can be seen that it rises and then descends, is maintained for a while, and then rapidly increases with the discharge pressure ratio.

This is because, in the case of FIG. 8B , the first back pressure chamber S1 is not formed because the sealing member is delayed in operation (injury delay) or does not operate, and leakage between the compression chambers in the vicinity of the center occurs. In addition, when the pressure in the second back pressure chamber S2 constituting the intermediate pressure space rises temporarily, the first back pressure chamber S1 is not formed and high-pressure oil flows into the second back pressure chamber S2, and the oil This is because the pressure in the second back pressure chamber S2 temporarily rises to generate some back pressure by the

Therefore, in the present embodiment, as described above, by optimizing the interval between the sealing member 36 and the sealing member insertion groove 336, it is possible to suppress the delay in the operation of the sealing member 36 in advance. 9 is a graph showing the change rate of the pressure ratio according to the ratio (%) of the radial spacing (particularly, the second spacing) of the sealing member to the outer diameter of the sealing member insertion groove (hereinafter, the spacing ratio).

As shown in this figure, it can be seen that the pressure ratio change rate is greatly increased when the interval ratio is 0.05% or less and 1.0% or more. Accordingly, it is preferable to form the gap ratio to be in the range of about 0.05 to 1.0%.

On the other hand, the sealing member according to the present embodiment is also affected by the shape of the operation.

That is, if the first sealing part 361 is too thin, it is vulnerable to wear and thus reliability may be reduced. On the contrary, if it is too thick, the weight may increase and operation delay may be induced.

In addition, if the second sealing part 362 is too thin, not only reliability is lowered, but also the sealing force may be reduced because it is too sensitive to the pressure change in the first back pressure chamber S1. Conversely, if it is too thick, the sealing member 36 The sealing force may be lowered because the deformation due to the pressure difference between the inner and outer sides is not smooth.

Therefore, it is preferable that the sealing member 36 properly forms the standard between the first sealing part 361 and the second sealing part 362 to increase reliability and sealing force. 10 is a schematic view showing the specification of the sealing member according to the present embodiment.

As shown, the first sealing part 361 of the sealing member 36 according to the present embodiment has a radial width L1 that is greater than or equal to an axial thickness t1, and the second sealing part ( 362 may be formed such that the radial thickness t2 is less than or equal to the axial length L2.

In addition, the axial thickness t1 of the first sealing part 361 may be greater than the radial thickness t2 of the second sealing part 362 . Accordingly, the first sealing part 361 can prepare for a reduction in lifespan due to abrasion with the frame 31, and the second sealing part 362 can be rapidly deformed in the radial direction to increase the radial sealing effect. can

In addition, the axial thickness t1 of the first sealing part 361 is the maximum distance (normally, stationary) between the frame 31 and the second scroll 33 on the outside of the sealing member 36 (the second back pressure chamber side). time interval) (G4) may be formed to be greater than or equal to. Accordingly, as the sealing member 36 is pushed and bent in the direction of the second back pressure chamber, the sealing member (exactly, the outer circumferential surface of the first sealing portion) 36 is bent by the oil in the first back pressure chamber S1. The edge of the outer peripheral surface 36b may be caught between the frame 31 and the second scroll 33 .

In view of this, in this embodiment, as shown in FIG. 11 , an anti-clamp portion 336c forming a first chamfer is formed at the corner of the sealing member insertion groove 336 , and the sealing member 36 is connected to the frame 31 and the frame 31 . Being caught between the second scrolls 33 can be suppressed in advance.

The snagging part 336c may be formed to be stepped or formed to be curved, but it may be preferable to be formed to be inclined in consideration of workability and the like.

In addition, the snagging prevention portion 336c is at the lower end thereof, that is, the height H3 of the portion in contact with the outer wall surface 336b of the sealing member insertion groove 336 is at least when the sealing member 36 comes into contact with the frame 31 . It is preferable to be formed to be located within the range of the first sealing portion (361). Accordingly, even if the sealing member 36 tries to be pushed out by the pressure of the first back pressure chamber S1 in a state in which the sealing member 36 is in contact with the frame 31 , the relatively thick first sealing part 361 is the pressure of the first back pressure chamber S1 . can withstand the pressure and not be pushed outward.

Although not shown in the drawings, the snagging part may be formed on the edge of the outer circumferential surface of the sealing member, or may be formed on the edge of the sealing member insertion groove and the edge of the sealing member, respectively.

On the other hand, as the sealing member 36 according to the present embodiment is formed in a 'L' cross-sectional shape as described above, the first sealing part 361 forms a friction surface compared to the conventional sealing member having a rectangular cross-sectional shape. thickness becomes thinner. Therefore, the material of the sealing member 36 is preferably formed of a material having abrasion resistance as much as possible.

To this end, in the sealing member 36 according to the present embodiment, a wear-resistant additive may be mixed with Teflon (PTFE). As the abrasion resistance additive, powder particles may be mixed or carbon fiber may be mixed.

However, it is preferable that the carbon fiber is mixed as compared to the powder particles are mixed because the abrasion resistance can be further improved. This is because it is easier for powder particles to be removed from Teflon than for carbon fibers to break.

In addition, the sealing member 36 may further include a lubricating additive such as graphite. In this case, the sealing member 36 has improved lubricity, so that the wear amount can be significantly reduced.

Meanwhile, as described above, the first back pressure chamber S1 is formed between the lower surface of the frame 31 and the corresponding upper surface of the second end plate 331 of the second scroll 33 . To this end, a step surface for forming the first back pressure chamber S1 is formed on the lower surface of the frame 31 or the upper surface of the second end plate 331 (which is formed on the second end plate in the drawing).

That is, as shown in FIG. 7 , the second scroll height H1 on the inside of the sealing member insertion groove 336 , that is, the height on the side where the first gap G1 is formed, is the second scroll height on the outside ( H2), that is, is formed to be lower than the height of the side where the second gap G2 is formed.

Accordingly, the inner surface 331b located on the inner side of the sealing member insertion groove 336 on the rear surface of the second end plate portion 331 is located on the outer side, and a predetermined height is higher than the outer surface 331c constituting the thrust bearing surface. formed lower. Then, the third gap G3 between the frame 31 and the second scroll 33 inside the sealing member insertion groove 336 directly connected to the first gap G1 is directly connected to the second gap G2. It is formed to be larger than the fourth gap G4 between the outer frame 31 of the sealing member insertion groove 336 and the second scroll 33, and is formed on the inner surface 331b of the second end plate 331. A space in which the first back pressure chamber S1 may be formed may be provided. At the same time, the high-pressure fluid may be rapidly introduced into the first gap G1.

At this time, as shown in FIG. 12 , an oil guide portion 336d that forms a second chamfer and guides oil to the sealing member insertion groove 336 may be formed at the edge of the sealing member insertion groove 336 . The oil guide part 336d forms a chamfer at the edge where the inner surface 331b of the second scroll 33 and the inner wall surface 336a of the sealing member insertion groove 336 are connected, so that the high-pressure fluid is quickly sealed. It can be introduced into the inside of the member insertion groove (336).

In the scroll compressor according to the present embodiment as described above, when the compressor starts operation, the compression unit 30 sucks and compresses the refrigerant and discharges the refrigerant at high pressure to the upper space 10a of the casing 10 .

Then, as shown in FIG. 13A , the high-pressure refrigerant flows into the sealing member insertion groove 336 through between the frame 31 and the orbiting scroll 33 together with the oil, and this high-pressure refrigerant is the first of the sealing member 36 . The lower surface of the sealing part 361 and the inner peripheral surface of the second sealing part 362 are pressed.

Then, as shown in FIG. 13b , the sealing member 36 floats by the pressure applied to the lower surface of the first sealing part 361 and the upper surface of the first sealing part 361 is in close contact with the lower surface of the frame 310 in the axial direction. will seal Here, as the orbiting scroll 33 pivots, the first sealing part 361 pivots with its upper surface in sliding contact with the lower surface (thrust bearing surface) of the frame 31 . Accordingly, the first sealing part 361 is worn between the frame 31 and the reliability may be reduced due to wear during long-term operation, but the axial thickness t1 of the first sealing part 361 is It is at least thicker than the radial thickness T2 of the second sealing part 362 , so that the life of the sealing member 36 can be secured long.

In addition, the second sealing part 362 is the second sealing part 362 is bent outward by the pressure applied to the inner peripheral surface of the second sealing part 362, the outer wall surface 336b of the sealing member insertion groove 336 ) to seal in the radial direction.

Here, since the second sealing part 362 is made of a single annular shape without a cutout and is floated by the pressure of the sealing member insertion groove 336 , the second sealing part 362 has a radial thickness t2 of the second sealing part 362 . ) is too large, the second sealing part 362 may not be bent when starting, and leakage in the radial direction may occur.

However, as in the present embodiment, when the radial thickness t2 of the second sealing part 362 is formed to be smaller than the axial thickness t1 of the first sealing part 361 at least, the second sealing part 362) is bent rapidly even when the compressor is started to seal the radial direction of the sealing member insertion groove 336 , so that the performance of the compressor can be improved.

On the other hand, there are other embodiments of the sealing member according to the present invention as follows.

That is, in the above-described embodiment, the outer diameter of the first sealing portion and the outer diameter of the second sealing portion are formed to be the same, but in this embodiment, the outer diameter of the first sealing portion and the outer diameter of the second sealing portion are formed to be different.

For example, as shown in FIG. 14 , the outer diameter D31 of the first sealing part 361 may be formed to be slightly larger than the outer diameter D32 of the second sealing part 362 . For this reason, a stepped surface 36c is formed at a portion where the outer peripheral surface 361b of the first sealing part 361 and the outer peripheral surface 362b of the second sealing part 362 contact each other, and the outer peripheral surface of the first sealing part 361 . 361c forms a substantial friction surface with respect to the outer wall surface 336b of the sealing member insertion groove 336.

Accordingly, the axial length L21 of the sealing member 36 constituting the radial friction surface of the sealing member 36 may be reduced to the thickness t1 of the first sealing portion 361, through which the second Even if the gap G2 is reduced compared to the above-described embodiment, the operation delay of the sealing member 36 can be alleviated to a certain extent.

Also, as shown in FIG. 15 , the outer diameter D31 of the first sealing part 361 may be formed to be smaller than the outer diameter D32 of the second sealing part 362 . This is formed opposite to the embodiment of FIG. 14 described above. Even in this case, the step surface 36c is formed at the portion where the outer circumferential surface 361b of the first sealing part 361 and the outer circumferential surface 362b of the second sealing part 362 contact, but the substantial friction surface is mostly the second sealing part It is formed on the outer peripheral surface 362b of the part 362 . Accordingly, even in this case, the axial length L22 of the sealing member 36 constituting the radial friction surface of the sealing member 36 may be reduced to a length excluding most of the thickness t1 of the first sealing portion 361 . And through this, even if the second gap G2 is reduced compared to the above-described embodiment, the delay in operation of the sealing member 36 can be alleviated to a certain extent.

On the other hand, there are other embodiments of the sealing member according to the present invention as follows.

That is, in the above embodiment, the first sealing portion and the second sealing portion are formed to have the same cross-sectional area, respectively, but in this embodiment, the second sealing portion is formed to have different cross-sectional areas in the axial direction.

For example, as shown in FIG. 16 , an inclined surface 362c is formed on the inner peripheral surface of the second sealing part 362 so that the cross-sectional area decreases from the upper end to the lower end, or as shown in FIG. 17 , the inner peripheral surface of the second sealing part 362 and A predetermined pressing part 362d may be formed at a point where the lower surface of the first sealing part 361 meets.

Even in these cases, the radial thickness t21 ( t22 ) at the lower end of the second sealing part 362 is preferably formed thinner than the axial thickness t1 of the first sealing part 361 .

Since the sealing member according to the present embodiments as described above has the same basic configuration and operational effects as those of the above-described embodiments, a detailed description thereof will be omitted. However, in the embodiment of FIG. 16 , the thickness t21 of the lower end of the second sealing part 362 is formed thinner than the embodiment according to FIG. 10 , and an area capable of receiving pressure from the lower end in the axial direction can be secured Thereby, it is possible to secure the axial sealing force as well as the radial sealing force. In addition, in the embodiment of FIG. 17 , the radial thickness t22 at the lower end of the second sealing part 362 is remarkably thin to increase the radial sealing effect, while the pressure is applied in the axial direction by the pressing part 362d. It is possible to secure an axial sealing force by securing a receiving area.

Meanwhile, another embodiment for levitating the sealing member in the scroll compressor according to the present invention is as follows.

That is, in the above-described embodiments, the sealing member is floated by the pressure of the fluid flowing into the sealing member insertion groove, but in this embodiment, the elastic member 365 in the sealing member insertion groove 336 as shown in FIG. 18 . ) is installed so that the sealing member 36 can float by the elastic force of the elastic member 365 .

In this case, as the sealing member 36 is floated by the elastic member 365 , the sealing member 36 can be quickly floated even when the compressor is started, thereby increasing the sealing force in the axial direction.

Meanwhile, although not shown in the drawings, a curved surface may be formed between the lower surface of the first sealing part and the inner peripheral surface of the second sealing part. In this case, it is possible to suppress damage between the first sealing portion and the second sealing portion.

10: casing 20: electric part
30: compression unit 31: frame
32: first scroll 323: first lap
33: second scroll 332: second wrap
336: sealing member insertion groove 336a: inner wall
336b: outer wall 36: sealing member
36a: inner circumferential surface of the sealing member 36b: outer circumferential surface of the sealing member
361: first sealing part 362: second sealing part
371: first oil supply passage 372: second oil supply passage
375: pressure reducing rod 40: flow path separation unit
50: rotation shaft 50a: oil supply passage
51: first bearing part 52: second bearing part
53: eccentric part 60: oil feeder
70: accumulator G1: first interval
G2: second gap S1: first back pressure chamber
S2: second back pressure chamber V: compression chamber
F _O : Sliding part oil supply passage V _O : Compression part oil passage

Claims (19)

first scroll;
a second scroll forming a compression chamber together with the first scroll while rotating with respect to the first scroll;
a frame coupled to the first scroll to support the second scroll;
a sealing member insertion groove formed in an annular shape on at least one of one side of the second scroll or one side of the frame in contact with the second scroll; and
a sealing member formed in an annular shape and inserted into the sealing member insertion groove to radially separate a gap between the second scroll and the frame;
The sealing member,
The cross-sectional area of the inner circumferential surface is formed to be smaller than the cross-sectional area of the outer circumferential surface, and the second interval between the outer circumferential surface of the sealing member and the outer wall surface of the sealing member insertion groove is the third between the inner circumferential surface of the sealing member and the inner wall surface of the sealing member insertion groove Formed less than or equal to 1 interval,
The gap between the second scroll and the frame is formed such that an inner gap in a radial direction with respect to the sealing member insertion groove is larger than an outer gap in a radial direction,
The scroll compressor according to claim 1, wherein a first passage communicating between the inner gap and the outer gap is formed in the second scroll or the frame. According to claim 1,
The second gap is formed to be 0.05 to 1.0% of the outer diameter of the sealing member. According to claim 1,
and a first chamfer is formed on at least one of an outer edge of the sealing member insertion groove and an outer edge of the sealing member. According to claim 3, The sealing member,
A first sealing portion formed in an annular shape, one surface of which forms an axial sealing surface with the frame, and annularly extending from the other surface of the first sealing portion, the outer circumferential surface of the sealing member insertion groove being the outer wall surface and the radial sealing surface Consists of a second sealing part forming a,
An axial height of the first chamfer is formed to be less than or equal to an axial thickness of the first sealing part. According to claim 1, wherein the sealing member,
A first sealing portion formed in an annular shape, one surface of which forms an axial sealing surface with the frame, and annularly extending from the other surface of the first sealing portion, the outer circumferential surface of the sealing member insertion groove being the outer wall surface and the radial sealing surface Consists of a second sealing part forming a,
An outer diameter of the first sealing portion and an outer diameter of the second sealing portion are formed to be the same. According to claim 1, wherein the sealing member,
A first sealing portion formed in an annular shape, one surface of which forms an axial sealing surface with the frame, and annularly extending from the other surface of the first sealing portion, the outer circumferential surface of the sealing member insertion groove being the outer wall surface and the radial sealing surface Consists of a second sealing part forming a,
The outer diameter of the first sealing portion and the outer diameter of the second sealing portion are formed to be different,
and a stepped surface is formed at a portion where an outer circumferential surface of the first sealing portion and an outer circumferential surface of the second sealing portion contact each other. delete According to claim 1,
The sealing member is a scroll compressor, characterized in that formed of a material mixed with Teflon (PTFE) and carbon fiber. 9. The method of claim 8,
The scroll compressor, characterized in that the sealing member further comprises a graphite material. According to claim 1,
The sealing member is formed in a 'L'-shaped cross-sectional shape, and a portion in contact with the frame is thicker than a portion in contact with the sealing member insertion groove. delete According to claim 1,
The scroll compressor according to claim 1, wherein a second passage is formed in the first scroll or the frame to communicate the outer gap to the compression chamber. a casing in which oil is stored in the inner space;
a driving motor provided in the inner space of the casing;
a rotating shaft coupled to the driving motor;
a frame provided under the driving motor;
a first scroll provided under the frame and having a first wrap formed on one side thereof;
A sealing member insertion groove is formed on a surface in contact with the frame, provided between the frame and the first scroll, a second wrap engaged with the first wrap is formed, and the rotation shaft overlaps the second wrap in a radial direction. a second scroll coupled as eccentrically as possible and configured to form a compression chamber between the first scroll and the first scroll while rotating with respect to the first scroll;
a sealing member formed in an annular shape and inserted into the sealing member insertion groove, provided between the frame and the second scroll to separate the interval between the frame and the second scroll into an inner interval and an outer interval,
The sealing member,
a first sealing portion formed in an annular shape, one surface of which forms an axial sealing surface with the frame; and
A second sealing part extending in an annular shape from the other surface of the first sealing part and having one end bent by the pressure of the refrigerant introduced into the sealing member insertion groove so that the outer circumferential surface forms a radial sealing surface with the outer wall surface of the sealing member insertion groove includes,
A radial width L1 of the first sealing portion is greater than an axial thickness t1 of the first sealing portion, and an axial thickness t1 of the first sealing portion is greater than a radial thickness t2 of the second sealing portion. formed large,
The scroll compressor according to claim 1, wherein a radial thickness (t2) of the second sealing portion is smaller than an axial length (L2) of the second sealing portion. 14. The method of claim 13,
A plurality of oil passages for guiding the oil stored in the casing to the outer circumferential surface of the rotation shaft are formed in the rotation shaft,
and at least one oil passage among the plurality of oil passages is formed to communicate with an inner gap separated by the sealing member. 15. The method of claim 14,
The outer gap communicates with the compression chamber forming an intermediate pressure between the suction pressure and the discharge pressure in the compression chamber,
The second scroll or frame is further formed with a communication passage for communicating the inner gap and the outer gap,
The scroll compressor, characterized in that the communication passage is provided with a decompression unit. 16. The method of claim 15,
The outer gap is formed to have a smaller gap between the frame and the second scroll than the inner gap,
The scroll compressor according to claim 1, wherein a chamfer inclined toward the sealing member insertion groove is formed at an edge of the sealing member insertion groove in contact with the outer gap. 17. The method of claim 16,
The outer diameter of the first sealing portion and the outer diameter of the second sealing portion are formed to be different,
and a stepped surface is formed at a portion where an outer circumferential surface of the first sealing portion and an outer circumferential surface of the second sealing portion contact each other. 18. The method according to any one of claims 13 to 17,
The sealing member is a scroll compressor, characterized in that formed of a material mixed with Teflon (PTFE) and carbon fiber. 19. The method of claim 18,
The scroll compressor, characterized in that the sealing member further comprises a graphite material.

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