JP4613908B2 - Rotary compressor - Google Patents

Description

  The present invention relates to a rotary compressor, and more particularly to an improvement in the structure of a rotary compressor.

<Overall configuration of rotary compressor>
With reference to FIG. 5 and FIG. 6, the whole structure of a rotary compressor is demonstrated. 5 is a longitudinal sectional view showing the entire configuration of the rotary compressor, and FIG. 6 is a sectional view taken along line VI-VI in FIG. The rotary compressor has a casing 1, and the casing 1 is sealed by the upper end opening of the cylindrical intermediate cylinder 2 being closed by the upper lid 3 and the lower end opening being closed by the lower lid 4. It is configured in a sealed structure. A suction pipe 5 for introducing a gas as a refrigerant into the casing 1 is connected to the lower end side of the intermediate cylinder 2, and a discharge pipe 6 for discharging the high-pressure compressed gas compressed in the casing 1 to the outside is connected to the upper lid 3. Is connected.

  A compression element 7 for sucking and compressing gas is disposed on the lower end side of the casing 1 in correspondence with the suction pipe 5, and a drive element 8 for operating the compression element 7 is disposed almost above the entire interior space. It is arranged to occupy. In the internal space defined by the lower lid 4 at the lower end portion of the casing 1, an oil reservoir 9 for storing the lubricating oil O is formed, and in other spaces, a storage space 10 for storing the compressed gas is formed. .

<Compression element 7>
The compression element 7 has a cylinder 12 having a cylinder chamber 11 having a circular cross-sectional shape, and a front head 13 having a boss-like bearing portion 13a at the center on both the upper and lower surfaces of the cylinder 12 and a boss at the center. The cylinder head 11 is hermetically sealed by fastening a plurality of bolts 15 to the rear head 14 having a cylindrical bearing portion 14a.

  The peripheral edge of the cylinder 12 is fixed to the inner wall surface of the intermediate cylinder 2 of the casing 1 and is supported in the casing 1 in a horizontal state. The muffler member 16 is fixed to the front head 13 so as to provide an annular gap around the bearing portion 13 a of the front head 13 with the muffler member 16.

  The cylinder 12 is provided with a suction port 12a, and the suction pipe 5 and the cylinder chamber 11 communicate with each other by inserting the suction pipe 5 into the suction port 12a. A discharge port 12b is formed on the side of the suction port 12a of the cylinder 12, and the discharge port 12b communicates with a recess 12c formed on the back side thereof. The recess 12c is a through hole (illustrated) formed in the front head 13. Omission) communicates with the storage space 10. As a result, the cylinder chamber 11 communicates with the storage space 10.

  In the recess 12c, a leaf spring-like discharge valve 17 is arranged to be supported by a pin 18 so that the discharge port 12b can be opened and closed, and the backflow of the compressed gas discharged into the storage space 10 into the cylinder chamber 11 is prevented.

  A piston 19 is disposed in the cylinder chamber 11 of the cylinder 12. The piston 19 includes an annular roller 20 having a circular insertion hole 20a, and a rectangular plate-like blade 21 integrally projecting radially outward on the side wall of the roller 20. The roller 20 is eccentrically arranged in the cylinder chamber 11 by a crankshaft 26 described later.

  Between the suction port 12a and the discharge port 12b of the cylinder 12, there is provided a blade sliding groove 12d extending outward in the cylinder radial direction, and the intermediate portion of the blade sliding groove 12d has a generally cylindrical shape (that The planar shape is a shape in which the upper and lower end portions of a substantially perfect circle shape are cut off), and a bush hole 12e that bulges outward from both sides of the blade sliding groove 12d is formed. In this bush hole 12e, two substantially semi-cylindrical block-shaped blade bushes 22 that constitute a rotation clamping body are arranged so as to be rotatable around a rotation center Q. The blade 21 of the piston 19 is sandwiched so as to be slidable in the radial direction of the cylinder from both sides by the blade bushing 22 while being inserted into the blade sliding groove 12d. It swings around.

<Drive element 8>
The drive element 8 includes an electric motor including a stator 24 and a rotor 25, and the stator 24 is fixedly supported on the inner wall surface of the intermediate cylinder 2 of the casing 1. The rotor 25 is arranged concentrically inside the stator 24 with a predetermined gap in the circumferential direction. The upper half portion of the crankshaft 26 is rotatably integrated around the shaft center P inside the rotor 25, and the lower half portion of the crankshaft 26 is rotatable to both bearing portions 13a and 14a of the front head 13 and the rear head 14. It is inserted and supported.

  An oil passage 26 a extending in the axial direction is formed in the crankshaft 26, and a centrifugal oil pump 27 is attached to the lower end of the crankshaft 26. The oil pump 27 is constantly immersed in the lubricating oil O of the oil reservoir 9, sucks the lubricating oil O into the oil passage 26 a according to the rotation of the crankshaft 26, and supplies it to the sliding portions of the compression element 7 and the driving element 8. It is like that.

  An eccentric shaft portion 26 b is provided near the lower end of the crankshaft 26. The eccentric shaft portion 26 b is located in the cylinder chamber 11 and is rotatably inserted into the insertion hole 20 a of the roller 20 of the piston 19. Accordingly, the roller 20 rotates eccentrically in the cylinder chamber 11 by the rotation of the crankshaft 26 around the axis P. The cylinder chamber 11 is divided into a suction chamber 11a and a compression chamber 11b by a blade 21.

  The volumes of the suction chamber 11a and the compression chamber 11b gradually change due to the eccentric rotational movement of the roller 20, and when the roller 20 is at the top dead center position that simultaneously closes the suction port 12a and the discharge port 12b, When the entire cylinder chamber 11 becomes the suction chamber 11a and the roller 20 is at the position of the bottom dead center 180 ° opposite to the cylinder chamber 11, the volume of the suction chamber 11a and the compression chamber 11b is equalized with the blade 21 as a boundary. It has become.

  The thus configured rotary compressor is used, for example, to compress refrigerant gas in a refrigerant circuit of an air conditioner. In this case, the refrigerant gas is sucked into the suction chamber 11a of the cylinder chamber 11 through the suction pipe 5 from the evaporator. The sucked refrigerant gas is compressed in the compression chamber 11b as the roller 20 rotates eccentrically. The refrigerant gas in a high pressure state is discharged from the discharge port 12b to the storage space 10 through a gap between the bearing portion 13a of the front head 13 and the muffler member 16, and further discharged to the condenser via the discharge pipe 6. The During this time, in the compression chamber 11b, the refrigerant gas is compressed in a mixed gas state in which the lubricating oil O is mixed. Therefore, the lubricating oil O is scattered in the mist state in the storage space 10, and the lubricating oil O in the mist state is It is separated from the refrigerant gas and collected in the oil sump 9. As a rotary compressor which consists of such a structure, what is published by the following patent document 1 is mentioned.

<Structure of blade bush 22>
Here, the structure of the blade bush 22 will be described in detail with reference to FIG. FIG. 7 is a partially enlarged sectional view for explaining the structure of the blade bush 22. The blade bush 22 includes a suction chamber side bush 22a that holds the blade 21 from the suction chamber 11a side, and a compression chamber side bush 22b that holds the blade 21 from the compression chamber 11a side. As described above, the blade bush 22 rotates about the rotation center Q with the eccentric rotation of the roller 20.

  Here, the process shown in FIG. 7 is a figure which shows the compression process step in which the volume of the compression chamber 11b becomes small. In this compression step, the rear side region R1 of the blade sliding groove 12d communicates with the storage space 10 in a high pressure state. Therefore, the pressure in the rear side region R1 is larger than the pressure in the suction chamber 11a. As a result, based on this pressure difference, a force (load F) pressed against the cylinder chamber 11 acts on the blade bush 22.

In particular, in the compression step shown in FIG. 7, the blade bush 22 is in a rotated position, and as shown in the enlarged sectional view of FIG. 8, a large load F is applied to the corner portion on the cylinder chamber 11 side of the suction chamber side bush 22a. Will be added. 8 is a partially enlarged cross-sectional view of a region surrounded by A in FIG. Here, the inner wall surface region A1 of the tip end portion of the bush hole 12e of the cylinder 12 shown in FIG. 8 is less rigid because the wall thickness is smaller than the other regions, so that the amount of wear on the inner wall surface may increase. In particular, when the difference between the pressure in the rear side region R1 and the pressure in the suction chamber 11a increases, it is conceivable that the amount of wear increases significantly. Further, in the suction start process from the end of compression, a large load F is applied to the corner portion on the cylinder chamber 11 side in the compression chamber side bush 22b as well as the suction chamber side bush 22a.
Japanese Patent Laid-Open No. 10-169580

  The problem to be solved by the present invention is caused by a load applied to a blade bush in a rotary compressor having a configuration in which a suction chamber and a compression chamber are partitioned by a blade integrally provided on a roller constituting a piston. Thus, the amount of wear on the inner wall surface of the bushing hole of the cylinder where the blade bushing is disposed is increased. Accordingly, the present invention has been made to solve the above-described problem, and includes a configuration capable of suppressing an increase in the amount of wear on the inner wall surface of the bush hole in which the blade bush provided in the cylinder is disposed. It is to provide a rotary compressor.

In the rotary compressor based on the present invention, a rotary piston inserted in the eccentric shaft portion of the crankshaft is disposed in a cylinder chamber provided in the cylinder, and a blade extending in the radial direction provided in the rotary piston is provided. The blade is slid and shaken by a blade bush disposed in a bush hole provided in the cylinder so as to constitute a part of the blade sliding groove while being inserted into a blade sliding groove formed in the cylinder. rotatably the sandwich, by rotating the crankshaft about its axis causes the eccentric rotating said rotary piston above the cylinder chamber, by swinging while sliding the blade by the blade to the cylinder chamber is divided into a suction chamber and a compression chamber, while the intake gas into the suction chamber, a rotary compressor for compressing in the compression chamber It has the following configuration.

The pressure in the back side region located on the opposite side of the cylinder chamber across the blade inserted in the blade sliding groove is higher than the pressure in the cylinder chamber, and the blade bushing is in contact with the blade. 1 side, a third side surface located on the side away from the second side, opposite to the cylinder chamber on the second side surface extending substantially perpendicularly from said blade located in the cylinder chamber side, and, opposite to the first side surface The corner portion where the second side surface and the fourth side surface intersect has a cross-sectional shape including a curved fourth side surface that contacts the side surface of the cylinder that defines the bush hole, and the radius is 0. A curved surface (angle R) of 1 mm or more is provided, and the contact point between the corner portion and the side surface of the cylinder defining the bush hole is not provided with the curved surface (angle R). To the point of contact, they are moved to the side away from the cylinder chamber.

  According to the rotary compressor of the present invention, as described above, the corner portion where the second side surface located on the cylinder chamber side of the blade bush and the fourth side surface contacting the side surface of the cylinder defining the bush hole intersect. As a shape, the radius is set to be a curved surface of 0.1 mm or more. As a result, the contact point between the corner portion and the side surface of the cylinder that defines the bush hole moves to the side away from the cylinder chamber.

  As a result, as a first action, the contact point moves in a direction in which the thickness of the cylinder increases. As a result, it is possible to receive a load from the blade bush at a position where the rigidity of the cylinder is high. Further, as the second action, since the side surface of the cylinder defining the bush hole is a curved surface, the component in the cylinder direction of the load at the contact point can be reduced by moving the contact point away from the cylinder chamber. (The tangential component force at the contact point is increased). Based on the first action and the second action described above, it is possible to suppress an increase in the amount of wear on the inner wall surface of the bush hole in which the blade bush provided in the cylinder is disposed.

  Hereinafter, embodiments of a rotary compressor based on the present invention will be described with reference to the drawings. The basic configuration of the rotary compressor in the present embodiment is the same as the structure of the rotary compressor described with reference to FIGS. 5 and 6, and the rotation inserted into the eccentric shaft portion 26 b of the crankshaft 26. The piston 20 is disposed in a cylinder chamber 11 provided in the cylinder 12, and a blade 21 extending in the radial direction provided in the rotary piston 20 is inserted into a blade sliding groove 12 d formed in the cylinder 12, and the blade slides. The blade 21 is slidably and slidably held by a blade bush 22 disposed in a bush hole 12e provided in the cylinder 12 so as to constitute a part of the groove 12d, and the crankshaft 26 is rotated about the axis P. Thus, the rotating piston 20 is eccentrically rotated in the cylinder chamber 11 and the blade 21 is swung while being slid. By 1 blade 21 is divided into a suction chamber 11a and the compression chamber 11b, while the suction in the suction chamber 11a of the gas, a rotary compressor for compressing in the compression chamber 11b.

  Accordingly, in the following description, the same or corresponding parts are denoted by the same reference numerals, and repeated description will not be repeated, and only characteristic components of the present invention will be described in detail below.

  First, with reference to FIG. 1 to FIG. 3, characteristic parts of the rotary compressor in the present embodiment will be described. FIG. 1 is an overall perspective view showing a structure of a blade bush 22A employed in the rotary compressor in the present embodiment, and FIG. 2 is a partially enlarged cross section corresponding to a region surrounded by A in FIG. FIG. 3 is a schematic diagram showing a state of a load applied from the suction chamber side bush 22a to the bush hole 12e. The blade bush 22A includes a suction chamber side bush 22a that holds the blade 21 from the suction chamber 11a (see FIG. 7) side, and a compression chamber side bush 22b that holds the blade 21 from the compression chamber 11a (see FIG. 7) side. Have.

The suction chamber side bush 22a and the compression chamber side bush 22b have a semi-cylindrical block shape, and basically have a line-symmetric shape with respect to the blade 21, but the suction chamber side bush 22a includes It has the following structural features. The suction chamber side bush 22a has a first side surface 221 that contacts the blade 21, a second side surface 222 that is located on the cylinder chamber 11 side and extends in a substantially vertical direction, and faces the second side surface 222 from the cylinder chamber 11. It has a cross-sectional shape including a third side surface 223 located on the far side and a curved fourth side surface 224 that faces the first side surface 221 and faces the side surface of the cylinder 12 that defines the bush hole 12e. . Further, a corner portion C1 where the second side surface 222 and the fourth side surface 224 intersect is provided with a curved surface (angle R) having a radius of 0.1 mm or more.

  Similarly to the suction chamber side bush 22a, the compression chamber side bush 22b also has a first side surface 221 that contacts the blade 21, a second side surface 222 that is located on the cylinder chamber 11 side and extends substantially vertically from the blade 11, and this second side surface. And a third side surface 223 located on the side facing away from the cylinder chamber 11 and a fourth side surface 224 having a curved shape facing the side surface of the cylinder 12 facing the first side surface 221 and defining the bush hole 12e. It has a cross-sectional shape. Further, a corner portion C1 where the second side surface 222 and the fourth side surface 224 intersect is provided with a curved surface (angle R) having a radius of 0.1 mm or more.

  Here, the load applied to the bush hole 12e from the suction chamber side bush 22a will be considered with reference to FIG. In FIG. 3, the contact point P1 indicates the contact point position between the corner portion of the suction chamber side bush 22a and the side surface of the cylinder 12 that defines the bush hole 12e, and the contact point P2 is shown in FIG. The contact point position between the corner portion of the suction chamber side bush 22a and the side surface of the cylinder 12 defining the bush hole 12e when the suction chamber side bush 22a shown as the background art is used is shown (the corner portion includes a radius Is provided with a curved surface (angle R) less than 0.1).

  The component F2 in the cylinder direction of the load F from the suction chamber side bush 22a at the contact point P2 can be expressed by F2 = [F × cos β]. On the other hand, the component force F1 in the cylinder direction of the load F from the suction chamber side bush 22a at the contact point P1 can be expressed by F1 = [F × cos α]. Here, since the contact point between the corner portion and the side surface of the cylinder that defines the bush hole is moved away from the cylinder chamber, β <α, and cos β> cos α is established. As a result, {F2 = [F × cos β]}> {F1 = [F × cos α]}. The same applies to the compression chamber side bush 22b as well as the suction chamber side bush 22a.

  Here, in FIG. 4, the bush hole wear amount characteristic when the corner portion C1 is provided with curved surfaces (corner R) having radii of 0.08 mm, 0.1 mm, 0.2 mm, and 0.35 mm as a graph Show. The material of the blade bush 22 is high-speed tool steel (SKH material), and the material of the cylinder 12 is cast iron (FC material). The refrigerant used is R410A. As shown in FIG. 4, when the radius of the corner portion C1 is 0.1 mm or more, the amount of wear on the side surface of the cylinder defining the bush hole (bush hole wear amount ratio) is within the steady wear region. It has been found that if it is less than 0.1 mm, it becomes an abnormal wear region.

  As described above, according to the rotary compressor based on the embodiment based on the present invention, in the blade bush 22A, the second side surface 222 located on the cylinder chamber 11 side and the side surface of the cylinder 12 defining the bush hole 12e are contacted. As the shape of the corner portion C1 where the fourth side surface 224 intersects, the radius is set to be a curved surface having a radius of 0.1 mm or more. As a result, the contact point between the corner portion C1 and the side surface of the cylinder 12 that defines the bush hole 12e can be moved to the side away from the cylinder chamber 11.

  As a result, the following points can be cited as the first action. In the case of the background art described in FIG. 8, the thickness of the contact point with the side surface of the cylinder 12 that defines the bush hole 12 e is a low-rigidity region smaller than the other regions. In the embodiment, since the contact point P2 is moved in the direction in which the thickness of the cylinder 12 is increased, it is possible to receive a load from the blade bush 22A at a highly rigid position where the thickness of the cylinder 12 is thick. Yes.

  Furthermore, the following points are mentioned as a 2nd effect | action. It is possible to reduce the component force F1 in the cylinder direction of the load F at the contact point P1 by moving the contact point between the corner portion C1 and the side surface of the cylinder 12 defining the bushing hole 12e away from the cylinder chamber 11. And Based on the first action and the second action described above, it is possible to suppress an increase in the amount of wear on the inner wall surface of the bush hole 12e in which the blade bush 22A provided in the cylinder 11 is disposed.

In the embodiment described above, the case where cast iron (FC material) is used as the material of the cylinder 12 is shown, but the same effect is obtained even when chromium molybdenum steel (SCM material) is used as the material of the cylinder 12. An effect can be obtained. Further, there is shown the case of using the R410A as a refrigerant, when using CO ₂ as refrigerant, differential pressure ratio between the suction chamber 11a and a rear side region R1 of the blade slide groove 12d, compared to R410A 3-4 times higher. Therefore, by employing the above configuration when CO ₂ is used as the refrigerant, it is possible to further suppress an increase in the amount of wear on the inner surface of the bush hole.

  Further, in the above-described embodiment shown in FIG. 1, the second side surface 222 and the bush located on the cylinder chamber 11 side are included in both the suction chamber side bush 22a and the compression chamber side bush 22b constituting the blade bush 22A. The case where a curved surface having a radius of 0.1 mm or more is employed as the shape of the corner portion C1 where the fourth side surface 224 that contacts the side surface of the cylinder 12 defining the hole 12e intersects is shown. Alternatively, the curved shape of the present invention can be adopted for any one of the compression chamber side bushes 22b.

  In the present embodiment, as a means for moving the contact point between the corner portion of the blade bush and the side surface of the cylinder defining the bush hole from the cylinder chamber, the second side surface located on the cylinder chamber side of the blade bush; As the shape of the corner where the fourth side that contacts the side of the cylinder that defines the bush hole intersects, a curved surface with a radius of 0.1 mm or more is adopted, but the contact point can be moved away from the cylinder chamber By adopting other configurations, it is possible to obtain the same operational effects as the above embodiment.

  Therefore, the above-described embodiment disclosed herein is illustrative in all respects and is not restrictive. The technical scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a whole perspective view which shows the structure of the blade bush employ | adopted as the rotary compressor in embodiment based on this invention. FIG. 8 is a partial enlarged cross-sectional view corresponding to a region surrounded by A in FIG. 7 in the rotary compressor according to the embodiment based on the present invention. It is a schematic diagram which shows the state of the load added to a bush hole from the suction chamber side bush. It is a figure which shows the bush hole wear amount characteristic at the time of providing the curved surface (corner R) whose radius is 0.08 mm, 0.1 mm, 0.2 mm, and 0.35 mm in the corner part C1. It is a longitudinal section showing the whole rotary compressor composition shown in background art. FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 5. It is a partial expanded sectional view for demonstrating the structure of the blade bush shown to background art. FIG. 8 is a partial enlarged cross-sectional view of a region surrounded by A in FIG. 7.

Explanation of symbols

1 casing, 2 intermediate cylinder, 3 upper lid, 4 lower lid, 5 suction pipe, 6 discharge pipe, 7 compression element, 8 drive element, 9 oil reservoir, 10 storage space, 11 cylinder chamber, 12 cylinder, 12a suction port , 12b Discharge port, 12c Recess, 12d Blade sliding groove, 12e Bush hole, 13 Front head, 13a, 14a Bearing part, 14 Rear head, 15 Bolt, 16 Muffler member, 17 Discharge valve, 18 Pin, 19 Piston, 20 Roller 20a insertion hole, 21 blade, 22, 22A blade bush, 22a suction chamber side bush, 22b compression chamber side bush, 24 stator, 25 rotor, 26 crankshaft, 26a oil passage, 26b eccentric shaft portion, 27 oil pump, 221
1st side surface, 222 2nd side surface, 223 3rd side surface, 224 4th side surface, A1 tip part inner wall surface area | region, R1 back side area | region, O lubricating oil.

Claims (2)

The rotating piston (20) inserted into the eccentric shaft portion (26b) of the crankshaft (26) is disposed in the cylinder chamber (11) provided in the cylinder (12), and is provided in the rotating piston (20). The blade (21) extending in the radial direction is inserted into the blade sliding groove (12d) formed in the cylinder (12), and the cylinder (12d) is configured to constitute a part of the blade sliding groove (12d). The blade (21) is slidably and slidably held by a blade bush (22) disposed in a bush hole (12e) provided in 12), and the crankshaft (26) is rotated around the axis (P). the rotary piston is rotated (20) causes eccentric rotation with the cylinder chamber (11), by swinging while sliding the blade (21), the said cylinder chamber (11) blades (21 ) to partition the suction chamber (11a) the compression chamber (11b), while the suction gas in the suction chamber (11a), compressed in the compression chamber (11b) That a rotary compressor,
The pressure in the back side region (R1) located on the opposite side of the cylinder chamber (11) across the blade (21) inserted into the blade sliding groove (12d) is the pressure in the cylinder chamber (11). Higher than the pressure of
It said blade bush (22) has a first side surface abutting on said blade (21) (221), said cylinder chamber (11) located on the side second side surface extending substantially perpendicular from said blade (222), the first 2 opposed to the side surface (222) the third side located on the side away from the cylinder chamber (11) (223), and said cylinder opposite to said first side surface (221) defining said bushing hole (12e) (12) having a cross-sectional shape including a curved fourth side surface (224) in contact with the side surface;
The corner portion where the second side surface (222) and the fourth side surface (224) intersect is provided with a curved surface (angle R) having a radius of 0.1 mm or more,
The contact point between the corner portion and the side surface of the cylinder (12) defining the bush hole (12e) is the cylinder chamber with respect to the contact point when the curved surface (angle R) is not provided. (11) Rotary compressor moved to the side away from it.   The rotary compressor according to claim 1, wherein the blade bush (22) is high-speed tool steel (SKH material), and the cylinder (12) is cast iron (FC material) or chrome molybdenum steel (SCM material). .

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