JP2005351289A - Retainer for thrust needle bearing, thrust needle bearing and compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a retainer for a thrust needle bearing, the thrust needle bearing and a compressor such as a car air conditioner capable of securing durability and reliability. <P>SOLUTION: In a pocket part 24p housing a roller 24a, a chamfered part C is provided on end faces of plate materials 24cl and 24c2 brought into contact with the roller 24a. Even when the chamfered part C is brought into contact with the roller 24a, they are abutted to each other in face, and thereby a lubricant deposited on an outer peripheral surface of the roller 24a is prevented from being removed, metal contact between the roller 24a and the retainer 24c can be restrained, and abrasion can be restrained. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  TECHNICAL FIELD The present invention relates to a thrust needle bearing roller suitable for use in a compressor, a transmission for an automobile, and the like, and a thrust needle bearing using the roller.

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 has a drive shaft that is rotatably supported by a radial bearing with respect to a housing, and a rotary support plate that is tiltably connected to the drive shaft. Near the outer periphery of the swash plate, a sliding shoe is mounted at equal intervals in the circumferential direction, holding the piston so that it can reciprocate in the cylinder. The refrigerant gas flowing into the bore of this cylinder is compressed and discharged Like to do. In other words, the swash plate performs a so-called razor movement, thereby causing the piston to reciprocate in the axial direction via the sliding shoe, thereby compressing and discharging the refrigerant gas (see Patent Document 1).
JP 2002-266754 A JP 2003-97562 A

  By the way, in recent years, higher output, higher speed, lower noise, higher efficiency, etc. of automobiles have been advanced, and the specifications required for each part have become strict. As a specific example, there is an example in which an electromagnetic clutch is abolished in a car air conditioner compressor from the viewpoint of overall efficiency of the car. In such a case, the compressor main shaft that has been conventionally rotated by ON / OFF of the electromagnetic clutch has always been rotated. In other words, the drive shaft of the compressor, the swash plate, etc. are always rotating while the engine is running.

  From another point of view, it can be said that the efficiency of the vehicle as a whole has been improved, but there are some cases where it is against efficiency when viewed by individual parts. For example, since the drive shaft that drives the swash plate is always rotating, the bearing that supports it is always operating, and its drag torque and wear become a problem. In particular, since general car cooler compressors are severely lubricated, it is necessary to suppress torque, lubricity, and temperature rise in a constantly rotating state.

  However, in the conventional technology, the plate material is finished in the shape of a cage, and the pocket part is pressed in the final process, but in this pocket formation, it is completed without any special post-processing by simply pulling out the part where the roller enters in the press. However, in such a cage, the roller comes in contact with the edge of the pocket portion of the cage, so that the lubricant on the outer diameter portion of the roller is scraped off by this edge, and sufficient lubricant is applied. If not supplied, there is a concern that abnormal wear may occur due to metal contact with the cage. Furthermore, if abnormal wear progresses, flaking or the like may occur, and eventually the rotation failure of the bearing, that is, the function as a compressor is impaired.

  On the other hand, Patent Document 2 discloses a technique for suppressing wear of a thrust needle bearing used in an environment where lubrication is severe. According to such a conventional technique, the edge load is reduced by adjusting the crowning of the roller as the rolling element. Such a technique can be expected to have a certain effect when the bearing has a sufficient fatigue life. However, since the length of one roller is halved, the load capacity of the bearing is reduced. is there. Furthermore, since the length of the roller is shortened and the ratio of the length to the roller diameter is close to 1, there is a problem that it is difficult to process.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems of the prior art, and it is an object of the present invention to provide a thrust needle bearing retainer, a thrust needle bearing, and a compressor such as a car cooler that can ensure durability and reliability.

The thrust needle bearing retainer of the present invention is a thrust needle bearing retainer having a plurality of rollers and a retainer that presses a plate material and retains the rollers.
In the pocket portion in which the roller is accommodated, the end surface of the plate material in contact with the roller is chamfered.

  A thrust needle bearing retainer according to the present invention is a thrust needle bearing retainer having a plurality of rollers and a retainer formed by press-molding a plate material to retain the rollers. Since the chamfered end face of the plate material in contact with the roller, even if the chamfered part comes into contact with the roller, it is suppressed that the lubricant adhering to the outer peripheral surface of the roller is scraped off, Metal contact between the roller and the cage can be suppressed, and wear can be suppressed.

  The amount of chamfering is preferably 5 to 30% of the thickness of the plate material.

  The chamfer is preferably formed by surface pressing. That is, the chamfering process of the cage can be performed by punching the pocket with a press and then performing the chamfering process with a press, thereby reducing the processing cost.

  The cage is preferably used for roller guidance. When the cage is a roller guide, compared to the case of a race guide, because the cage is on the roller, the edge of the pocket will always contact the outer diameter surface of the roller, Therefore, the effect of the present invention can be exhibited more.

  The hardness of the cage is preferably Hv 400 to 600. Thus, since the hardness of the said retainer is made low, the aggression property with respect to the roller of the said retainer also falls. If the cage is too hard, the roller will be worn, and conversely if it is too soft, the cage will be worn, so there is an appropriate range, and this range has been confirmed by experiments described later.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a swash plate compressor of a car air conditioner in which a shaft according to the present embodiment is incorporated.

  As shown in FIG. 1, a compressor 11 as a driven device includes a cylinder block 12, a front housing 13 joined to the front end surface thereof, a valve plate 14, and a valve plate 14 on the rear end surface of the cylinder block 12. The rear housing 15 is joined. The housing of the compressor 11 is configured by fastening these members 12, 13, 14 and 15 with a plurality of through bolts 16 (only one is shown).

  The drive shaft 17 is rotatably supported at the center of the cylinder block 12 and the front housing 13 via a pair of front and rear radial bearings 18. The drive shaft 17 has a spherical seat 17a at the center thereof. A lip seal 19 is interposed between the outer peripheral surface of the front end portion of the drive shaft 17 and the inner peripheral surface of the support cylinder portion 13 a protruding from the front side of the front housing 13. A plurality of cylinder bores 20 are formed in the cylinder block 12 at equal angular intervals so as to surround the drive shaft 17. Each cylinder bore 20 extends in parallel with the drive shaft 17, and a single-headed piston 21 is fitted into each bore 20 so as to be capable of reciprocating. In each cylinder bore 20, a variable volume compression chamber 20 a is defined between the end face of the piston 21 and the valve plate 14.

  A crank chamber 22 is defined inside the front housing 13. In the crank chamber 22, the rotary support 23 is fixed to the drive shaft 17 so as to be integrally rotatable. A thrust needle bearing 24 is interposed between the front end surface of the rotary support 23 and the inner wall surface of the front housing 13. A pair of support arms 25 project from the rear surface of the rotary support 23 toward the cylinder block 12, and a guide portion (in the case of FIG. 1) constituting a hinge mechanism when the swash plate tilts at the tip of each arm. Hole) 26 is formed.

  A swash plate 27 is disposed in the crank chamber 22. The swash plate 27 is substantially disk-shaped and has a central hole 27a through which the drive shaft 17 is inserted. The inner surface of the central hole 27a has a concave spherical shape corresponding to the spherical seat 17a. Therefore, when the central hole 27a is fitted to the outer surface of the spherical seat 17a of the drive shaft 17, both can slide relative to each other. Become. The central hole 27a slides on the spherical seat 17a, so that the swash plate 27 can swing (variable angle, that is, tilt) on the spherical seat of the drive shaft 17. Since the lubrication conditions of the compressor are generally severe, chemical conversion coating treatment such as manganese phosphate is applied to at least one of the outer surface of the spherical seat 17a and the inner surface of the central hole 27a as necessary to improve lubricity. . On the front surface of the swash plate 27, a connecting body 28 that constitutes a hinge mechanism with the rotary support 23 is projected. A part of this mechanism is slidably arranged in the guide portion 26 of the support arm 25 to constitute a hinge mechanism. A swash plate 27 is tiltably connected to the rotary support 23 via the hinge mechanism. In the case of this figure, the connecting body 28 is inserted into the guide portion 26 of the arm. However, the guide portion 26 and the connecting body 28 may be inserted through the pins so as to be skewered from the side. . The drive shaft 17 and the swash plate 27 constitute a swash plate tilting mechanism 100. Each outer periphery of the swash plate 27 is connected to each piston 21 via a thrust needle bearing 80 that is a pair of thrust rolling bearings and a pair of hemispherical shoes 29.

  Along with the rotation of the drive shaft 17, the swash plate 27 rotates together with the rotation support 23, and each piston 21 is reciprocated in the cylinder bore 20.

  A storage chamber 30 is formed at the center of the cylinder block 12 so that the rear end of the drive shaft 17 can be stored. A suction passage 31 is formed in the valve plate 14 and the rear housing 15. The front end of the suction passage 31 is communicated with the storage chamber 30, and the rear end is connected to the external refrigerant circuit 32. The external refrigerant circuit 32 includes at least a condenser 33, an expansion valve 34, and an evaporator 35.

  An annular suction chamber 36 is defined in the rear housing 15, and the suction chamber 36 communicates with the storage chamber 30 through a communication port 37. A discharge chamber 38 is further defined in the rear housing 15, and the discharge chamber 38 is connected to the external refrigerant circuit 32 via a discharge passage 39 formed in the housing. A suction port 40 and a discharge port 41 are formed in the valve plate 14 for each cylinder bore 20. A suction valve 42 for opening and closing the suction port 40 is disposed on the cylinder block 12 side of the valve plate 14. A discharge valve 43 for opening and closing the discharge port 41 is disposed on the discharge chamber 38 side of the valve plate 14.

  A blocking body 45 is accommodated in the accommodation chamber 30 of the cylinder block 12. Between the swash plate 27 and the blocking body 45, a substantially annular thrust needle bearing 47 is provided on the drive shaft 17 so as to receive an axial load to the rear of the shaft 17, and a load to the rear of the shaft 17. I am trying to receive it. Note that the inclination angle of the swash plate means an angle formed by a plane perpendicular to the drive shaft 17 and the swash plate 27.

  As shown in FIG. 1, a regulation protrusion 48 is formed on the lower front surface of the swash plate 27 to regulate excessive inclination. The maximum inclination angle of the swash plate 27 is regulated by the contact between the regulating projection 48 and the rotary support 23. An inclination-decreasing spring 49 interposed between the rotary support 23 and the swash plate 27 urges the swash plate 27 in the minimum inclination direction.

  The pressure release passage 50 communicates the crank chamber 22 and the internal space of the blocking body 45. A pressure release passage 51 as a throttling is formed through the rear end of the cylindrical portion of the block body 45, and the inside of the block body 45 communicates with the inside of the accommodation chamber 80 through the pressure release passage 51.

  A series of air supply passages 52 are formed in the cylinder block 12, the valve plate 14 and the rear housing 15 constituting the housing of the compressor 11. The air supply passage 52 communicates the discharge chamber 38 with the crank chamber 22. A capacity control valve 53 attached to the rear housing 15 is provided in the middle of the air supply passage 52. The control valve 53 has a solenoid 54 that is excited and demagnetized by energization control from an external controller (not shown). As the solenoid 54 is energized or demagnetized, the control valve 53 is closed or opened. The pressure supply from the discharge chamber 38 to the crank chamber 22 is controlled according to the opening / closing control of the capacity control valve 53, and the internal pressure of the crank chamber 22 is adjusted. The inclination angle of the swash plate 27 is determined according to the internal pressure of the crank chamber 22.

  Next, a power transmission mechanism that transmits a driving force from the vehicle engine 62 as a driving source to the driving shaft 17 of the compressor 11 will be described.

  An electromagnetic clutch 55 is disposed on the front side of the front housing 13. The electromagnetic clutch 55 includes a pulley 56, a hub 57, an armature 58 and a solenoid 59. The solenoid 59 is excited and demagnetized by energization control from an external controller (not shown).

  The pulley 56 is rotatably supported on the support cylinder portion 13 a of the front housing 13 via an angular bearing 60. A belt 61 is hung between the pulley 56 and the pulley 62 a of the vehicle engine 62, and the pulley 56 is operatively connected to the vehicle engine 62 via the belt 61.

  The metal hub 57 has a substantially cylindrical shape, and is fixed or coupled to the front end portion of the drive shaft 17 by a bolt 63 so as to be integrally rotatable. A disk-shaped armature 58 is disposed around the hub 57 so as to be able to contact and separate from the front surface of the pulley 56.

  Next, the basic operation of the compressor 11 as described above will be described taking a compressor with a clutch as an example. During operation of the engine 62, the driving force of the engine 62 is transmitted to the pulley 56 of the electromagnetic clutch 55 via the belt 61, and the pulley 56 is always rotated. When there is a cooling load in the external refrigerant circuit 32, the external controller excites the solenoid 59, and the armature 58 is adsorbed and joined to the front surface of the pulley 56 by the generated electromagnetic force. Then, the rotational force of the pulley 56 integrated with the armature 58 is transmitted to the hub 57 and the drive shaft 17. On the other hand, when there is no cooling load in the external refrigerant circuit 32, the external controller demagnetizes the solenoid 59 to eliminate the electromagnetic force, and the armature 58 is separated from the front surface of the pulley 56. Then, the operating connection between the drive shaft 17 and the engine 62 is released.

  FIG. 1 shows a state in which the swash plate 27 is at the maximum inclination angle. In this state, the capacity control valve 53 is closed by the excitation of the solenoid 54 and the air supply passage 52 is closed. Therefore, the compressed refrigerant gas corresponding to the discharge pressure Pd is not supplied from the discharge chamber 38 to the crank chamber 22 through the supply passage 52, and the internal pressure Pc of the crank chamber 22 is a relatively low pressure (that is, the suction chamber 36). The pressure gradually approaches the pressure Ps), the angle of the swash plate 27 is maintained at the maximum inclination angle, and the compression operation at the maximum discharge capacity is performed.

  As a result of the compression operation at the maximum discharge capacity, when the cooling load becomes small, the solenoid 54 is demagnetized and the capacity control valve 53 is opened by the reverse operation to that described above. As a result, the crank chamber pressure Pc is increased, and the swash plate 27 is quickly shifted from the maximum inclination state to the minimum inclination state.

  FIG. 2 is a cross-sectional view of the thrust needle bearing 24 according to the present embodiment. FIG. 3 is a view of the configuration of FIG. 2 taken along the line II-II and viewed in the direction of the arrow. As shown in FIG. 2, the thrust needle bearing 24 includes a roller 24a that is a rolling element, a retainer 24c that holds the roller 24a and presses and combines two plate members 24c1 and 24c2, and a race. 24b and used for roller guidance. The cage 24c is formed by punching a pocket 24p that accommodates the rollers 24a with a press. However, as shown in FIG. The chamfered portion C is formed. The amount Δ of the chamfered portion C (length in the thickness direction of the plate material) is preferably in the range of Δ = 0.05 t to 0.30 t, where t is the thickness of the plate material. The hardness of the plate members 24c1 and 24c2 is Hv400 to 600.

  According to the present embodiment, since the chamfered portion C is provided on the end surfaces of the plate members 24c1 and 24c2 in contact with the roller 24a in the pocket portion 24p in which the roller 24a is accommodated, even if the chamfered portion C contacts the roller 24a, the surface Therefore, scraping of the lubricant attached to the outer peripheral surface of the roller 24a is suppressed, metal contact between the roller 24a and the cage 24c can be suppressed, and wear can be suppressed.

  FIG. 4 is a cross-sectional view of a thrust needle bearing 24 'according to another embodiment, but the race is omitted. As shown in FIG. 4, the thrust needle bearing 24 ′ has a cage 24 c ′ that is pressed so that the two plate members 24 c 1 ′ and 24 c 2 ′ are opposed to each other so as to be in close contact with each other radially outward. ing. Although not shown, also in the present embodiment, chamfered portions are formed on the plate members 24c1 'and 24c2' as in FIG. About points other than a shape, it is the same as that of embodiment mentioned above.

  Fig. 5 is a cross-sectional view of a thrust needle bearing 24 "according to still another embodiment. Fig. 6 is a view of the cage shown in Fig. 5 as viewed in the direction of arrow VI. The thrust needle bearing 24 ″ includes a roller 24a that is a rolling element, a cage 24c ″ that is formed by bending one plate member that holds the roller 24a, and races 24b ″ and 24d ″. In the present embodiment, when the cage 24c ″ moves relative to the roller 24a in the circumferential direction, the two points C1, C3 on the race 24b ″ side in FIG. It is necessary to chamfer at least these portions (see FIG. 6) in order to contact the roller 24a at the point C2 on the side. Ah .

The present inventors conducted a test for determining the relationship between the hardness of the cage, the chamfering amount, and the degree of roller wear. The test results are shown in Table 1.
Test conditions (1) Bearing used: φ40 × φ60
(2) Roller: φ3
(3) Number of revolutions: 5000 min ⁻¹
(4) Axial load: 4000N
(5) Thickness of cage: t = 0.8 (mm)
(6) Lubricating oil: white kerosene + PAG

  In the test results shown in Table 1, it was confirmed that when chamfering was not performed at the pocket portion of the cage, roller wear occurred regardless of the hardness of the cage. That is, it was confirmed that roller wear is suppressed by chamfering. However, it was also found that the chamfering effect is small when the chamfering amount is 0.04 or less. Furthermore, wear of the cage was confirmed in the cage having a hardness of Hv372 or less. On the other hand, in a cage having a hardness of Hv772 or higher, roller wear was confirmed even after chamfering.

  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.

It is sectional drawing of the compressor of the car air conditioner in which the needle bearing concerning this Embodiment was integrated. It is sectional drawing of the thrust needle bearing 24 concerning this Embodiment. It is the figure which cut | disconnected the structure of FIG. 2 by the III-III line, and looked at the arrow direction. It is sectional drawing of the thrust needle bearing 24 'concerning another embodiment. FIG. 6 is a cross-sectional view of a thrust needle bearing 24 ″ according to another embodiment. It is the figure which looked at the holder | retainer shown in FIG. 5 in the arrow VI direction.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Compressor 12 Cylinder block 13 Front housing 13a Support cylinder part 14 Valve plate 15 Rear housing 16 Bolt 17 Drive shaft 18 Radial bearing 19 Lip seal 20 Cylinder bore 20a Compression chamber 21 Piston 22 Crank chamber 23 Rotation support body 24 Thrust needle bearing 25 Support arm 26 Guide part 27 Swash plate 28 Connection body 29 Shoe 30 Accommodating chamber 31 Suction passage 32 External refrigerant circuit 33 Condenser 34 Expansion valve 35 Evaporator 36 Suction chamber 37 Communication port 38 Discharge chamber 39 Discharge passage 40 Suction port 41 Discharge port 42 Suction Valve 43 Discharge valve 45 Blocking body 46 Suction passage opening spring 47 Thrust needle bearing 48 Restriction projection 49 Inclination decreasing spring 52 Air supply passage 53 Control valve 54 Solenoid 55 Electromagnetic clutch 56 pulley 57 hub 58 armature 58a stepped portion 59 solenoid 60 angular bearings 61 belt 62 engine 62a pulley 63 volts

Claims (7)

In a thrust needle bearing retainer having a plurality of rollers and a retainer configured to press the plate material and retain the rollers,
A retainer for a thrust needle bearing, wherein a chamfer is applied to an end face of a plate material in contact with the roller in a pocket portion in which the roller is accommodated.   The cage of a thrust needle bearing according to claim 1, wherein the amount of chamfering is 5 to 30% of the thickness of the plate material.   The cage according to claim 1 or 2, wherein the chamfer is formed by a surface pressing process.   The thrust needle bearing retainer according to any one of claims 1 to 3, wherein the retainer is used for roller guidance.   The thrust needle bearing retainer according to any one of claims 1 to 4, wherein the retainer has a hardness of Hv400 to 600.   A thrust needle bearing using the cage according to any one of claims 1 to 5. A compressor using the thrust needle bearing according to claim 6.

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