JP2005207439A - Retainer for needle bearing, needle bearing, and compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a retainer for a needle bearing capable of reducing abrasion of each section and a car air conditioner compressor using it. <P>SOLUTION: The retainer 16h comprises metal plate materials 16h1 and 16h2 having an opening pocket section 16p for storing a roller 16e, and at least part of the edge of the pocket section is formed of a folded section of the plate material. Thus, even when the roller 16e violently relatively moves in the pocket section 16p, the roller 16e collides and contacts with a relatively smooth folded section. Therefore, comparing with the conventional art, abrasion of the roller or the pocket section can be suppressed effectively, and abrasion powder can be suppressed from dropping to the raceway surface. <P>COPYRIGHT: (C)2005,JPO&amp;NCIPI

Description

  The present invention relates to a cage for a needle bearing suitable for use in a compressor or the like, a needle bearing and a compressor using them, and further to a needle bearing suitable for use in an automatic transmission for automobiles.

For example, a variable capacity compressor is known as one type of compressor for a car air conditioner (also called a car cooler compressor). In general, a variable displacement compressor supports a drive shaft rotatably with respect to a housing by a radial bearing, a rotary plate is attached to the drive shaft, and a swash plate has a variable inclination angle with respect to the rotary plate. It is attached to. A thrust bearing is disposed between the rotating plate and the housing. One end of a plurality of piston rods is attached to the swash plate at equal intervals in the circumferential direction, and the other end of each piston rod is connected to the piston. The piston is provided so as to slide inside a cylinder provided in the housing, and compresses and discharges the refrigerant gas flowing into the bore of the cylinder. That is, when the swash plate rotates, the piston reciprocates in the axial direction via the piston rod, and compresses and discharges the refrigerant gas (see Patent Document 1).
JP 2002-266754 A

  By the way, during operation of the compressor for a car air conditioner, the drive shaft receives a large force through the swash plate. Therefore, there are a thrust bearing that supports the drive shaft in the thrust direction with respect to the housing, and a radial bearing that supports the drive shaft in the radial direction. Necessary. In such a case, since the needle bearing has needle-shaped cylindrical rollers, the thickness in the axial direction is thin, and the configuration can be made more compact by using it in a compressor for a car air conditioner.

  However, general compressors for car air conditioners transmit the force generated by the rotation of the crank to the drive shaft through the electromagnetic clutch via the belt, and from the low speed rotation such as idling to the time of acceleration. Since the compressor capacity changes as necessary within a wide range of rotational speeds up to high-speed rotation, the engine is operated with a complex combination of rotational speed and load. Since it is used in such an environment, naturally, the thrust needle bearing and the radial needle bearing are similarly operated under a wide range of conditions from high speed rotation to low speed rotation, and further from a no-load state to a heavy load state.

  Here, the thrust needle bearing used in the conventional compressor for a car air conditioner may employ a steel plate press cage from the viewpoint of cost reduction and heat resistance improvement. However, since the rotational speed of the thrust needle bearing is synchronized with the rotational speed of the engine, if the engine rotational speed changes abruptly, rotational fluctuation also occurs in the thrust needle bearing. When the rotational fluctuation occurs in this way, the roller and the steel plate cage follow up, and the roller repeatedly comes into contact with the edge of the pocket of the cage. However, if the pocket of the cage is formed by punching with a press, the roughness of the periphery of the pocket deteriorates, and in some cases, a sharp edge may occur.

  Therefore, if the roller repeatedly hits the edge of such a pocket many times, the rolling surface of the roller may be damaged, or the raceway surface may be prematurely worn due to wear particles of the roller or cage. There is a concern. In particular, in car air-conditioning compressors, the lubrication conditions are very severe, so there is a situation where measures against wear are required. On the other hand, it is conceivable to eliminate the sharp edges or improve the roughness by polishing the edges of the pockets, but this increases the cost of the cage.

  It is also possible to use a cage as a resin to prevent the roller from being damaged and to prevent the raceway surface from being accelerated by the influence of wear powder, but there is a concern that the strength is inferior to that of a steel plate.

  The present invention has been made in view of the above-described problems, and provides a needle bearing retainer, a needle bearing, and a car cooler compressor using the same that can reduce wear of each part. Objective.

The cage for the needle bearing of the present invention,
The cage is made of a metal plate having an opening in a pocket portion for accommodating rollers, and at least a part of an edge of the pocket portion is formed by a bent portion of the plate material.

  According to the cage for a needle bearing of the present invention, the cage is made of a metal plate material having an opening in a pocket portion that accommodates rollers, and at least a part of the edge of the pocket portion is a bent portion of the plate material. Therefore, even when the roller is relatively moved in the pocket portion, it is not a sharp edge with a relatively low roughness as in the prior art, but hits a relatively smooth bent portion. Wear of the roller and the pocket portion can be effectively suppressed.

  A needle bearing is preferably constructed from the needle bearing retainer and the rollers held by the retainer, and a car cooler compressor is desirably constructed using the needle bearing.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a compressor of a car air conditioner in which a needle bearing according to the present embodiment is incorporated, and FIG. 2 is a view of the configuration of FIG. 1 viewed in the II direction.

  In FIG. 1, a housing 6 constituting the compressor 1 includes a central short cylindrical body 7 sandwiched between a head case 8 and a swash plate case 9 from both sides in the axial direction (left-right direction in FIG. 1). It is united by coupling bolts (not shown). Inside the head case 8, low-pressure chambers 10 and 10 and a high-pressure chamber 11 are provided. Note that not only the inside of the high pressure chamber 11 but also the inside of the low pressure chambers 10 and 10 are positive. A flat partition plate 12 is sandwiched between the main body 7 and the head case 8. The low-pressure chambers 10 and 10 represented as being divided into a plurality of parts in FIG. 1 communicate with each other and communicate with a single suction port 13 (FIG. 2) provided on the outer surface of the head case 8. . The high pressure chamber 11 communicates with a discharge port (not shown) provided in the head case 8. The suction port 13 communicates with the outlet of an evaporator (not shown), and the discharge port (not shown) communicates with the inlet of a condenser (not shown).

  A shaft 14 is rotatably supported in the housing 6 in a state of being spanned between the main body 7 and the swash plate case 9. More specifically, both ends of the shaft 14 are rotatably supported with respect to the main body 7 and the swash plate case 9 by a pair of radial needle bearings 15A and 15B, and a pair of thrust needle bearings 16A and 16B. Thus, the thrust load applied to the shaft 14 can be supported freely.

  The thrust needle bearing 16A has a plurality of rollers 16a, raceways 16b and 16c that clamp the rollers 16a in the axial direction (left and right in FIG. 1), and a cage 16d that holds the rollers 16a. Further, the thrust needle bearing 16B includes a plurality of rollers 16e, race rings 16f and 16g that sandwich the rollers 16e in the axial direction (left and right direction in FIG. 1), and a cage 16h that holds the rollers 16e.

  The radial needle bearing 15A includes a plurality of rollers 15a, an outer ring (orbital ring) 15b, and a cage 15c that holds the rollers 15a. Furthermore, the radial needle bearing 15B according to the present embodiment includes a plurality of rollers 15d, an outer ring (orbital ring) 15e, and a cage 15f that holds the rollers 15d.

  FIG. 3 is a cross-sectional view showing a part of the thrust needle bearing 16B. FIG. 4 is a view of the configuration of FIG. 3 taken along line IV-IV and viewed in the direction of the arrow. In FIG. 3, a cage 16h is formed by combining metal plate members 16h1 and 16h2 having flanges on the inner and outer peripheral edges so that the flanges are superposed. In FIG. 4, the plate members 16h1 and 16h2 are formed with pocket portions 16p for accommodating the rollers 16e.

  FIG. 5 is a perspective view showing a part of one plate member 16h1, but the other plate member 16h2 has the same shape. The plate material 16h1 punches out the position that becomes the pocket portion 16p into a craft shape. Thereafter, as shown by a dotted line, the punched portion is bent to both sides in the circumferential direction, and a pocket portion 16p having a smooth R edge is formed as shown in a cross section in FIG. The punched portion may be bent inward or a part of the axial direction may be bent.

  The thrust needle bearing 16A is provided via a disc spring 18 between a part of the main body 7 and a step portion 17 formed at one end portion (right end side in FIG. 1) of the shaft 14. The thrust needle bearing 16 </ b> B is disposed between the disc portion 19 and the swash plate case 9 that are fitted and fixed to the outer peripheral surface of the intermediate portion of the shaft 14. A plurality of (for example, six in the example shown in the figure in the circumferential direction) cylinder holes 20, 20 are formed in the periphery of the shaft 14 inside the main body 7 constituting the housing 6. Sliding portions 22, 22 provided in the front half (right half in FIG. 1) of the pistons 21, 21 are respectively provided inside the plurality of cylinder holes 20, 20 formed in the main body 7 in this manner. It is fitted so that it can be displaced in the direction.

  Here, a space provided between the bottom surfaces of the cylinder holes 20 and 20 and the tip surfaces (right end surfaces in FIG. 1) of the pistons 21 and 21 is referred to as a compression chamber 23. The space existing inside the swash plate case 9 is a swash plate chamber 24. A swash plate 25 is fixed at a predetermined inclination angle with respect to the shaft 14 at a portion located in the swash plate chamber 24 on the outer peripheral surface of the intermediate portion of the shaft 14, and the swash plate 25 rotates together with the shaft 14. I try to do it. A plurality of locations in the circumferential direction of the swash plate 25 and the pistons 21 and 21 are connected by a pair of sliding shoes 26 and 26, respectively. For this reason, the inner side surfaces (surfaces facing each other) of these sliding shoes 26 and 26 are flat surfaces so as to be in sliding contact with portions on both side surfaces of the swash plate 25 that are also flat surfaces. Further, the outer side surfaces of these sliding shoes 26, 26 (side surfaces opposite to the mating sliding shoe 26) are spherical convex surfaces. Further, the outer surfaces of the sliding shoes 26 and 26 are positioned on a single spherical surface with the inner surface thereof being in contact with both side surfaces of the swash plate 25. On the other hand, a driving force transmission mechanism is constructed with sliding shoes 26 and 26 and a swash plate 25 at the base end of each piston 21 and 21 (the end far from the partition plate 12 and the left end in FIG. 1). The connecting portions 27 and 27 are formed integrally with the pistons 21 and 21, respectively. The connecting portions 27 and 27 are formed with holding portions 28 and 28 for holding the pair of sliding shoes 26 and 26. The holding portions 28 and 28 are formed with spherical concave surfaces that are in close sliding contact with the outer surfaces of the sliding shoes 26 and 26 so as to face each other.

  Further, a pair of guide surfaces (not shown) for each piston 21, 21 is provided on the part of the inner peripheral surface of the main body 7 that is aligned with the outer end of each connecting portion 27, 27. They are spaced apart in the circumferential direction. The outer end portions of the connecting portions 27 and 27 are guided by the guide surfaces, and can only be displaced in the axial direction of the pistons 21 and 21 (left and right direction in FIG. 1). Therefore, the pistons 21 and 21 are also prevented from rotating around the central axis of the pistons 21 and 21 in the cylinder holes 20 and 20 due to the rotation of the swash plate 25, and can only be displaced in the axial direction (non-rotatable). ). As a result, the connecting portions 27 and 27 push and pull the pistons 21 and 21 in the axial direction as the swash plate 25 is oscillated and displaced by the rotation of the shaft 14. , 20 to reciprocate in the axial direction.

  On the other hand, in order to partition the low-pressure chamber 10 and the high-pressure chamber 11 from the cylinder holes 20, 20, the partition plate 12 sandwiched between the abutting portions of the main body 7 and the head case 8 includes the low-pressure chamber 10 and the cylinder holes 20. , 20 and the discharge holes 30, 30 communicating with the high-pressure chamber 11 and the cylinder holes 20, 20 are formed in a state of penetrating in the axial direction. Accordingly, the opening on the cylinder hole 20, 20 side at one end (the left end in FIG. 1) of each suction hole 29, 29 and each discharge hole 30, 30 is opposed to the tip surface of each piston 21, 21. In addition, a reed valve type suction that allows refrigerant gas to flow only from the low-pressure chamber 10 toward each cylinder hole 20, 20 in a part of each cylinder hole 20, 20 facing one end of each suction hole 29, 29. Valves 31 are provided. Further, in the high-pressure chamber 11, the refrigerant gas is allowed to flow only from the cylinder holes 20, 20 toward the high-pressure chamber 11 in the portion facing the other end (right end in FIG. 1) opening of each discharge hole 30, 30. A reed valve type discharge valve 32 is provided. The discharge valve 32 is provided with a stopper 33 that restricts displacement in a direction away from the discharge holes 30.

  The shaft 14 of the compressor 1 configured as described above is rotationally driven via an endless belt 42 by a vehicle engine (not shown). For this reason, in the case of the illustrated example, the driven pulley 35 around the support cylinder portion 34 provided in the center of the outer surface (left side surface in FIG. 1) of the swash plate case 9 constituting the housing 6 is connected to a double row radial ball. The bearing 36 is rotatably supported. The driven pulley 35 has a U-shaped cross section and is formed in an annular shape as a whole. A solenoid 37 fixed to the outer surface of the swash plate case 9 is disposed in the internal space of the driven pulley 35. On the other hand, a mounting bracket 38 is fixed to a portion protruding from the support cylinder portion 34 at the end of the shaft 14, and an annular plate 39 made of a magnetic material is supported around the mounting bracket 38 via a plate spring 40. doing. When the solenoid 37 is not energized, the annular plate 39 is separated from the driven pulley 35 by the elastic force of the leaf spring 40 as shown in the figure. However, when the solenoid 37 is energized, the annular plate 39 is attracted toward the driven pulley 35. The rotational force from the driven pulley 35 to the shaft 14 can be freely transmitted. That is, the solenoid 37, the annular plate 39, and the leaf spring 40 constitute an electromagnetic clutch 41 for engaging and disengaging the driven pulley 35 and the shaft 14. Further, an endless belt 42 is stretched between a driving pulley and a driven pulley 35 fixed to an end of a crankshaft (not shown) of a vehicle engine.

  The operation of the compressor of the car air conditioner according to the present embodiment will be described. When the car air conditioner is operated to cool or dehumidify the passenger compartment, the electromagnetic clutch 41 is operated to engage the driven pulley 35 and the shaft 14, thereby causing the vehicle to pass through the endless belt 42. The power of the engine is transmitted to the shaft 14 and is driven to rotate. As a result, the swash plate 25 rotates to reciprocate the sliding portions 22 and 22 constituting the plurality of pistons 21 and 21 in the cylinder holes 20 and 20, respectively. As the sliding portions 22 and 22 reciprocate, the refrigerant gas sucked from the suction port 13 is sucked into the compression chamber 23 from the low pressure chambers 10 and 10 through the suction holes 29 and 29. . The refrigerant gas is compressed in each of the compression chambers 23 and then sent to the high-pressure chamber 11 through the discharge holes 30 and 30 and is discharged from the discharge port. After that, the high-temperature and high-pressure refrigerant gas is cooled by a condenser to become a liquid refrigerant, and then rapidly expanded to flow into the evaporator as a low-temperature and low-pressure mist refrigerant, where the air supplied to the passenger compartment After cooling, the refrigerant gas is sucked into the compressor.

  In the case of a cage made of a conventional metal plate material, the pocket part was formed by punching, so if the roller moves violently within the pocket part, the roller generally has a rough surface or a sharp edge. As a result, there was a risk of causing early wear of the rollers and the cage, and causing wear powder to fall on the raceway surface, thereby further promoting wear. On the other hand, according to the present embodiment, in FIG. 4, even if the roller 16e moves violently in the pocket portion 16p, the roller 16e comes into contact with a relatively smooth surface with an R. Since it is a bent part, compared with the prior art, it is possible to effectively suppress the wear of the rollers and the pocket part, and it is also possible to suppress the wear powder from falling on the raceway surface.

  FIG. 6 is a cross-sectional view similar to FIG. 3 of the thrust needle bearing according to the second embodiment. The thrust needle bearing retainer 16h ′ according to the present embodiment has a configuration in which the flanges on the outer peripheral sides of the disks 16h1 ′ and 16h2 ′ are omitted from the embodiment shown in FIG. have. Although not shown in the drawing, the plate members 16h1 ′ and 16h2 ′ are punched into a hand shape at the position where the pocket portion 16p ′ is formed, and the punched portion is bent, as in the above-described embodiment. It is possible to obtain effects such as suppression of wear.

  The cage may be bent in the axial direction of the roller (that is, the radial end portion of the pocket in the radial direction). When the cage is bent in this way, the roller end surface is bent by the cage even when the roller end surface and the cage pocket end surface come into contact with each other due to centrifugal force, vibration, etc. that accompany rotation during bearing operation. It can be touched on a smooth surface. Furthermore, even when the finish of the roller end face is poor, it is possible to make contact with the smooth surface of the cage, so that wear of both the roller and the cage can be suppressed.

  The present invention has been described above with reference to the embodiments. However, the present invention is not limited to the above-described embodiments, and can of course be changed or improved within the scope of the invention. For example, not only one roller is accommodated in one pocket, but two or more rollers may be accommodated. The needle bearing of the present invention can be used for, for example, an automatic transmission for automobiles in addition to a car cooler compressor.

It is sectional drawing of the compressor of the car air conditioner in which the needle bearing concerning this Embodiment was integrated. It is the figure which looked at the structure of FIG. 1 in the II direction. It is sectional drawing which shows a part of thrust needle bearing 16B. It is the figure which cut | disconnected the structure of FIG. 3 by the IV-IV line and looked at the arrow direction. It is a perspective view which shows a part of one board | plate material 16h1. It is sectional drawing similar to FIG. 3 of the thrust needle bearing concerning 2nd Embodiment.

Explanation of symbols

1 Compressor for car air conditioner 6 Housing 14 Shaft 15A, 15B Radial needle bearing 16A, 16B Thrust needle bearing

Claims (3)

In the cage for needle bearings,
The cage is made of a metal plate having an opening in a pocket portion that accommodates rollers, and at least a part of an edge of the pocket portion is formed by a bent portion of the plate material. Cage   A needle bearing comprising the cage for a needle bearing according to claim 1 and a roller held by the cage. A compressor using the needle bearing according to claim 2.

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