JPH1047244A - Power transmission mechanism of cluthless variable capacity compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power transmission mechanism of a clutchless variable capacity compressor, which is simple in structure, the function of which is little deteriorated even under the environment of low temperature, and by which fluctuation of load torque on the compressor side can be effectively lightened. SOLUTION: An interposing member 89 comprising a connecting part 91 formed of a metallic material and an elastic deforming part 90 formed of a thermoplastic resin material is disposed between a driving shaft 16 and a pulley 17. The interposing member 89 is connected to one of the driving shaft 16 and the pulley 17, and it is always pressed to the other to be integrally rotated. When the load torque on the driving shaft 16 side fluctuates, the elastic deforming part 90 is elastically deformed. If the load torque becomes excessive, the elastic deforming part 91 is fused by frictional heat produced by the relative sliding of the press-contacting parts.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power transmission mechanism for a clutchless variable displacement compressor in which an external drive source and a drive shaft are always operatively connected via a belt and a pulley.

[0002]

2. Description of the Related Art Generally, a clutchless variable displacement compressor does not include an electromagnetic clutch for connecting and disconnecting power transmission between an external drive source and a drive shaft of the compressor. For this reason, especially in the state of being mounted on the vehicle, it is possible to eliminate the poor feeling of feeling due to the shock of the intermittent operation of the electromagnetic clutch. Further, since the power consumption and weight of the electromagnetic clutch are large, it is possible to reduce the power consumption of the compressor, reduce the overall weight, and reduce the cost.

[0003] However, in such a clutchless variable displacement compressor, fluctuations in load torque on the compressor side are directly reduced to a vehicle engine serving as an external drive source without being reduced. For this reason, there is a possibility that the operating state of the vehicle engine fluctuates due to the fluctuation of the load torque on the compressor side.

In order to deal with such a problem, for example, Japanese Unexamined Utility Model Publication No. Sho 63-142460 (first publication) and Japanese Unexamined Patent Publication No. 8-121332 (second publication) disclose such techniques. 2. Description of the Related Art A clutchless variable displacement compressor has been conventionally proposed.

[0005] In the compressor disclosed in the first publication, an engagement recess is provided on an annular protruding wall formed on a pulley, and an engagement recess is provided on a peripheral surface of a hub. One end of the drive lever is inserted into the engagement recess on the protruding wall side,
The other end of the drive lever is inserted into the engagement recess on the hub side via an annular leaf spring. Usually, the rotation of the pulley is transmitted to the drive shaft via the drive lever and the leaf spring.

Further, when the load torque on the compressor side fluctuates, the fluctuation of the load torque is reduced by the swinging of the drive lever and the elastic deformation of the leaf spring, and the fluctuation of the load torque of the vehicle engine is caused. The rotation speed fluctuation is suppressed. Further, when the load torque on the compressor side becomes excessive, the other end of the drive lever is disengaged from the concave portion of the leaf spring, so that the excessive load torque does not reach the vehicle engine side.

On the other hand, in the compressor disclosed in the second publication, a power transmission is fixed to an end of a drive shaft, and an annular ring is provided between an outer peripheral surface of the power transmission and an inner peripheral surface of the pulley. A rubber damper is interposed. The inner peripheral surface of the elastic rubber is connected to a power transmission body with an adhesive, and the outer peripheral surface of the rubber damper is connected to a pulley with an adhesive.

[0008] Usually, the rotation of the pulley is transmitted to the drive shaft via a rubber damper and a power transmission body.
Here, when the load torque on the compressor side fluctuates, the fluctuation of the load torque is reduced by the elastic deformation of the rubber damper, and the rotation speed fluctuation of the vehicle engine caused by the fluctuation of the load torque is suppressed. Also, if the load torque on the compressor side becomes excessive, the rubber damper itself breaks,
Excessive load torque is prevented from spreading to the vehicle engine.

[0009]

However, in the conventional compressor disclosed in the first gazette, a plurality of drive levers are swingably supported, and the swing displacement of the drive levers is received by a leaf spring. It is supposed to be. Therefore, there is a problem that the structure of the power transmission mechanism is complicated, the number of parts and the number of assembling steps are increased, and the cost of the compressor is increased.

In the conventional compressor disclosed in the second publication, an annular rubber damper is interposed between the power transmission body and the pulley. Here, when the compressor is used in a cold region or the like in a low-temperature environment lower than the glass transition temperature of the rubber material of the rubber damper, the rubber material may be brittle at low temperatures. In this low-temperature embrittlement state, the rubber material becomes hard, its elasticity is greatly reduced, and it becomes brittle. For this reason,
There has been a problem that the rubber damper may not be able to effectively reduce the fluctuation of the load torque or may be inadvertently broken even if the load torque is not large.

The present invention has been made by paying attention to such problems existing in the prior art. The purpose is that despite the simple structure, there is almost no functional deterioration even in a low temperature environment, and the fluctuation of the load torque on the compressor side can be effectively mitigated.
An object of the present invention is to provide a power transmission mechanism of a clutchless variable displacement compressor that can reliably shut off transmission of overload torque.

[0012]

According to the first aspect of the present invention, there is provided a clutch in which an external drive source and a drive shaft are constantly operatively connected via a belt and a pulley. In the power transmission mechanism of the variable displacement compressor, an interposition member including a connecting portion made of a metal material and an elastically deforming portion made of a thermoplastic resin material is provided between the drive shaft and the pulley, The interposed member is coupled to one of the drive shaft and the pulley, and is always pressed against the other so as to be integrally rotatable. When the load torque on the drive shaft fluctuates, the elastically deformed portion of the interposed member Are elastically deformed, and when the load torque on the drive shaft side becomes excessive, the elastically deformed portion of the interposition member is melted by frictional heat generated by the relative sliding of the press contact portion.

According to a second aspect of the present invention, in the power transmission mechanism of the clutchless variable displacement compressor according to the first aspect, a power transmission body is fixed to the drive shaft, and the power transmission body is connected to the pulley. An interposed member is provided between the opposed end faces, and a connection portion of the interposed member is pressed against a power transmission body made of a metal material or a pulley made of a metal material.

According to a third aspect of the present invention, in the power transmission mechanism for a clutchless variable displacement compressor according to the first aspect, a power transmission body is fixed to the drive shaft, and the power transmission body is connected to the pulley. An interposed member is arranged between the opposed end faces, and an elastically deformed portion of the interposed member is pressed against a power transmission body made of a metal material or a pulley made of a metal material.

According to a fourth aspect of the present invention, in the power transmission mechanism for a clutchless variable displacement compressor according to the first aspect, the elastically deforming portion of the interposition member is fixedly connected to a drive shaft to transmit power. It is also used as a body.

According to the fifth aspect of the present invention, the first to fourth aspects are provided.
In the power transmission mechanism for a clutchless variable displacement compressor according to any one of the above, the connecting portion of the interposition member is formed of an iron-based metal material.

According to the sixth aspect of the present invention, the first to fifth aspects are provided.
In the power transmission mechanism for a clutchless variable displacement compressor according to any one of the above, the elastically deforming portion of the interposition member is made of a thermoplastic resin material containing a filler.

In the power transmission mechanism for a clutchless variable displacement compressor according to the first aspect, the pulley is constantly rotated via a belt by an external drive source such as a vehicle engine. Then, usually, the rotation of the pulley is transmitted to the drive shaft via the interposition member, and the compressor is operated for compression. If the load torque on the compressor side fluctuates during the operation of the compressor, the elastic deformation portion of the interposition member is elastically deformed, and the fluctuation of the load torque is reduced. Therefore, the fluctuation of the load torque on the compressor side is suppressed from spreading to the external drive source side.

Further, when the load torque on the compressor side becomes excessive, relative sliding occurs at the press contact portion between the interposition member and the drive shaft or the pulley, and frictional heat is generated. Then, the elastic deformation portion of the interposition member is melted by the frictional heat. As a result, the power transmission function of the interposition member is destroyed, and transmission of the overload torque from the drive shaft to the pulley is interrupted. For this reason, the overload torque is suppressed from being transmitted to the external drive source side and adversely affecting it.

Further, since the elastically deformable portion of the interposition member is formed of a thermoplastic resin material, the range of elasticity variation due to the temperature of the use environment of the elastically deformable portion is reduced as compared with the case where a rubber material is used. be able to. For this reason, even when the compressor is used in a low-temperature environment such as a cold region, the elastically deformable portion cannot effectively reduce the fluctuation of the load torque,
Inadvertent breakage with a small load torque can be suppressed.

In the power transmission mechanism for a clutchless variable displacement compressor according to the second aspect, the connecting portion of the interposition member made of a metal material is pressed against a power transmission body or a pulley on a drive shaft also made of a metal material. Have been. For this reason, when the load torque on the compressor side becomes excessive, relative sliding occurs at the press contact portion between the connection portion of the interposition member and the power transmission body or the pulley, and frictional heat is generated. Then, the frictional heat is transmitted from the connecting portion to the elastically deforming portion of the interposition member, the elastically deforming portion is melted, and thereafter, the connecting portion is rotated relative to the elastically deforming portion. Thereby, transmission of the overload torque from the drive shaft to the pulley is reliably shut off.

According to a third aspect of the present invention, in the power transmission mechanism for a clutchless variable displacement compressor, the elastically deforming portion of the interposition member made of a thermoplastic resin material has a power transmission body or a pulley on a drive shaft made of a metal material. Is pressed against.
For this reason, when the load torque on the compressor side is excessive, relative sliding occurs at the press contact portion between the elastically deforming portion of the interposition member and the power transmission body or the pulley, and frictional heat is generated. Due to this frictional heat, the vicinity of the pressure contact portion of the elastic deformation portion is melted,
Transmission of the overload torque from the drive shaft to the pulley is interrupted. Then, after the overload torque on the compressor side calms down and the heat generation of the press contact portion is reduced, the vicinity of the press contact portion of the elastically deforming portion of the interposition member is re-solidified from a molten state, and power transmission can be resumed. it can.

In the power transmission mechanism of the clutchless variable displacement compressor according to the fourth aspect, the elastically deforming portion of the interposition member is fixedly connected to the drive shaft so as to double as the power transmission body. . Therefore, it is not necessary to separately provide a power transmission body on the drive shaft, so that the number of parts can be reduced and the weight of the compressor can be reduced.

According to a fifth aspect of the present invention, in the power transmission mechanism for a clutchless variable displacement compressor, the connecting portion of the interposition member is
It is formed of an iron-based metal material having high thermal conductivity and rigidity. For this reason, especially in a configuration in which the connecting portion of the interposition member is pressed against the power transmission body or the pulley on the drive shaft made of a metal material, the frictional heat caused by the relative sliding of the pressing portion is interposed from the connecting portion. It is quickly transmitted to the elastically deforming part of the member. Then, the elastically deformed portion is quickly melted, and the transmission of the overload torque on the compressor side to the external drive source is reliably and promptly interrupted.

In the power transmission mechanism of the clutchless variable displacement compressor according to the present invention, the elastic deformation portion of the interposition member is made of a thermoplastic resin material containing a filler. For this reason, the strength of the elastic deformation portion is improved by the reinforcing effect of the filler, and the occurrence of inadvertent power transmission interruption with a small load torque is suppressed.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.

First, the configuration of the clutchless variable displacement compressor will be described. As shown in FIG. 1, a front housing 12, which also forms part of the housing, is joined to the front end of a cylinder block 11, which forms part of the housing. A rear housing 13, which also forms a part of the housing, is joined and fixed to the rear end of the cylinder block 11 via a valve plate 14. The crankcase 15, which also functions as a control pressure chamber, includes the front housing 1
2 and between the cylinder block 11.

The drive shaft 16 is rotatably supported between the front housing 12 and the cylinder block 11. The front end of the drive shaft 16 protrudes from the crank chamber 15 to the outside, and a pulley 17 is fixed to the protruding end. The pulley 17 has a belt 18
, Is always operatively connected to a vehicle engine (not shown) serving as an external drive source.

The pulley 17 is supported by the front housing 12 via an angular bearing 19. The axial load and the radial load acting on the pulley 17 are reduced by the angular bearing 1.
9 through the front housing 12.

A lip seal 20 is interposed between the front end of the drive shaft 16 and the front housing 12. The lip seal 20 prevents pressure leakage in the crank chamber 15.

A rotary support 21 is fixed to the drive shaft 16 and the swash plate 2 as a cam plate is fixed.
2 is slidably and tiltably supported in the axial direction of the drive shaft 16. A pair of guide pins 23 each having a spherical tip are fixed to the swash plate 22. A support arm 24 protrudes from the rotary support 21,
The support arm 24 has a pair of guide holes 25 formed therein. The guide pin 23 is slidably fitted in the guide hole 25.

The swash plate 22 can be tilted in the axial direction of the drive shaft 16 and can rotate integrally with the drive shaft 16 by the cooperation of the support arm 24 and the pair of guide pins 23. The tilting of the swash plate 22 is guided by the slide guide relationship between the guide hole 25 and the guide pin 23 and the slide support action of the drive shaft 16. When the center of the radius of the swash plate 22 moves toward the cylinder block 11, the inclination angle of the swash plate 22 decreases. Also, the rotating support 21
On the rear surface, an inclination regulating protrusion 21a for regulating the maximum inclination of the swash plate 22 is formed.

The inclination reducing spring 26 is provided on the rotating support 21.
And the swash plate 22. The inclination reducing spring 26 causes the swash plate 22 to move the cylinder block 11.
It is urged toward the side to decrease the tilt angle.

At the center of the cylinder block 11, a housing hole 27 is provided in the axial direction of the drive shaft 16, and its inner peripheral surface is formed to have substantially the same diameter over the entire length. A cylindrical blocking body 28 is slidably fitted and accommodated in the accommodation hole 27 from the rear side of the cylinder block 11. The blocking body 28 includes a large-diameter portion 28a and a small-diameter portion 2.
8b.

The drive shaft 16 is provided in the cylinder of the blocking body 28.
The rear end is inserted. A radial bearing 30 is fitted and supported on the inner peripheral surface of the large diameter portion 28a. The radial bearing 30 is provided with a circlip 31 attached to the inner peripheral surface of the large-diameter portion 28a.
From the inside of the cylinder. The rear end of the drive shaft 16 is slidably fitted into the radial bearing 30, and is supported on the peripheral surface of the housing hole 27 via the radial bearing 30 and the blocking body 28.

An annular groove 27a is formed in the inner peripheral surface of the rear end of the accommodation hole 27.
Circlip 27b is formed in the annular groove 27a.
Are detachably fastened. Inlet passage opening spring 29
Is interposed between the step between the large diameter portion 28a and the small diameter portion 28b of the blocking body 28 and the circlip 27b. The elastic coefficient of the suction passage opening spring 29 is set to be smaller than the elastic coefficient of the inclination decreasing spring 26, and the resultant force of the urging forces of both springs 26 and 29 is equal to the force in the rear direction of the compressor. Has become. And these springs 26, 2
The resultant of the urging force of No. 9 acts on the swash plate 22, a thrust bearing 34 and a blocking body 28 described later.

In the center of the rear housing 13, there is formed a suction passage 32 constituting a suction pressure region. The drive shaft 1 serving as a movement path of the blocking body 28
It is on the extension of 6. The suction passage 32 is opened on the rear side of the housing hole 27, and a positioning surface 33 is formed around the opening of the suction passage 32 on the housing hole 27 side. The positioning surface 33 is on the valve plate 14. Blocker 28
The distal end surface of the small diameter portion 28b can contact the positioning surface 33. The tip surface of the small-diameter portion 28b is positioned on the positioning surface 3.
The contact of the shutter 3 restricts the movement of the blocking body 28 in the rear direction.

On the drive shaft 16 between the swash plate 22 and the blocking body 28, a thrust bearing 34 is slidably supported on the drive shaft 16. The rotation of the swash plate 22 depends on the presence of the thrust bearing 34.
8 is blocked.

A single-head type piston 35 is provided in a plurality of cylinder bores 11 a penetrating through the cylinder block 11.
Is housed. The rotational movement of the swash plate 22 is converted into a reciprocating swing of each piston 35 via a pair of shoes 36, and as a result, the piston 35 is moved back and forth in the cylinder bore 11a.

In the rear housing 13, a suction chamber 37 and a discharge chamber 38 are defined. Valve plate 1
A suction port 39 and a discharge port 40 are formed on the cylinder bore 11a so as to correspond to the respective cylinder bores 11a.
And a discharge valve 42.

The refrigerant gas in the suction chamber 37 is supplied to the piston 35
The suction valve 41 is displaced from the suction port 39 by the returning operation from the top dead center position to the bottom dead center position, and the cylinder bore 1
1a. The refrigerant gas that has flowed into the cylinder bore 11a is compressed until it reaches a predetermined pressure by the forward movement from the bottom dead center position of the piston 35 to the top dead center position, and then pushes the discharge valve 42 out of the discharge port 40 to retreat. The liquid is discharged to the discharge chamber 38. The opening of the discharge valve 42 is regulated by contacting the retainer 43.

Rotary support 21 and front housing 12
, A thrust bearing 44 is interposed. The thrust bearing 44 receives a compression reaction force acting on the rotary support 21 from the cylinder bore 11a via the piston 35, the shoe 36, the swash plate 22, and the guide pin 23.

The suction chamber 37 is provided with the accommodation hole 2 through the opening 45.
It communicates with 7. The blocking body 28 is positioned on the positioning surface 3.
3, when the front end of the suction passage 32 is closed,
The opening 45 is shut off from the suction passage 32.

An axial passage 46 is formed in the drive shaft 16. An inlet 46a of the axial passage 46 opens into the crank chamber 15 near the lip seal 20, and an outlet 46b of the axial passage 46 opens into the cylinder of the shut-off body 28. A pressure release port 47 is provided through the peripheral surface of the blocking body 28. The pressure release port 47 is provided between the inside of the cylinder of the blocking body 28 and the accommodation hole 27.
And communicates.

The discharge chamber 38 and the crank chamber 15 are connected by an air supply passage 48. In the middle of the air supply passage 48, a capacity control valve 49 for opening and closing the air supply passage 48 is provided.
Is provided. Further, between the suction passage 32 and the displacement control valve 49, the suction pressure P
A pressure detection passage 50 for guiding s is formed.

The suction passage 32 serving as an inlet for introducing the refrigerant gas into the suction chamber 37 and the discharge flange 51 discharging the refrigerant gas from the discharge chamber 38 are connected by an external refrigerant circuit 52. In the external refrigerant circuit 52, a condenser 53, an expansion valve 54, and an evaporator 55 are interposed. The expansion valve 54 is composed of a temperature-type automatic expansion valve, and controls the flow rate of the refrigerant according to a change in the gas temperature at the outlet of the evaporator 55. A temperature sensor 56 is provided near the evaporator 55. The temperature sensor 56 detects the temperature in the evaporator 55, and the detected temperature information is sent to the control computer 57. Further, the control computer 57 is connected to a room temperature setting device 58, a room temperature sensor 59, an air conditioner operation switch 60, an engine speed sensor 61, and the like for designating a temperature in a vehicle compartment.

The control computer 57 includes, for example, a room temperature specified in advance by the room temperature setting device 58, a detected temperature obtained from the temperature sensor 56, a detected temperature obtained from the room temperature sensor 59, an on / off signal from the air conditioner operation switch 60, The input current value is commanded to the drive circuit 62 based on an external signal such as the engine speed obtained from the engine speed sensor 61. The drive circuit 62 outputs the commanded input current value to the coil 84 of the solenoid mechanism 65 of the displacement control valve 49 described later. Other external signals include, for example, a signal from an outdoor temperature sensor, and the input current value is determined according to the environment of the vehicle.

The displacement control valve 49 is constructed by joining a valve housing 64 and a solenoid mechanism 65 near the center. A valve chamber 66 is defined between the valve housing 64 and the solenoid mechanism 65, and a valve body 67 is housed in the valve chamber 66. A valve hole 68 is opened in the valve chamber 66 so as to face the valve body 67. The valve hole 68 is formed to extend in the axial direction of the valve housing 64. Further, a forced opening spring 69 is interposed between the valve body 67 and the inner wall surface of the valve chamber 66 to urge the valve body 67 in the opening direction of the valve hole 68. The valve chamber 66 communicates with a discharge chamber 38 in the rear housing 13 via a valve chamber port 70 and the air supply passage 48.

A pressure-sensitive chamber 71 is defined above the valve housing 64. The pressure sensing chamber 71 is communicated with the suction passage 32 of the rear housing 13 via the suction pressure introduction port 72 and the pressure detection passage 50. A bellows 73 is housed inside the pressure-sensitive chamber 71. A pressure-sensitive rod guide 74 that is continuous with the valve hole 68 is formed between the pressure-sensitive chamber 71 of the valve housing 64 and the valve chamber 66. The pressure-sensitive rod 75 is connected to the pressure-sensitive rod guide 7.
4 is slidably inserted into the inside. This pressure-sensitive rod 75
Thereby, the valve body 67 and the bellows 73 are operatively connected. The portion of the pressure sensing rod 75 on the side joined to the valve body 67 has a small diameter in order to secure a passage for the refrigerant gas in the valve hole 68.

A port 76 is formed in the valve housing 64 between the valve chamber 66 and the pressure sensing chamber 71 so as to be orthogonal to the valve hole 68. The port 76 is connected to the crank chamber 15 via the air supply passage 48. That is, the valve chamber port 70, the valve chamber 66, the valve hole 68, and the port 76 form a part of the air supply passage 48.

A fixed iron core 78 is fitted into the upper opening of the accommodation chamber 77 of the solenoid mechanism 65.
A solenoid chamber 79 is defined in the accommodation chamber 77 by the reference numeral 8. A movable iron core 80 having a substantially closed cylindrical shape is housed in the solenoid chamber 79 so as to be able to reciprocate. Movable iron core 8
A follow-up spring 81 is interposed between 0 and the bottom of the storage chamber 77. The follower spring 81 has a smaller elastic coefficient than the forcible release spring 69.

The fixed iron core 78 has a solenoid chamber 79.
A solenoid rod guide 82 that communicates with the valve chamber 66 is formed. The solenoid rod 83 is connected to the valve 6
7 and the solenoid rod guide 82
It is slidably inserted in the inside. The end of the solenoid rod 83 on the movable iron core 80 side is
9 and the follower spring 81 are in contact with the movable iron core 80. The movable core 80 and the valve body 67 are operatively connected via a solenoid rod 83.

Outside the fixed core 78 and the movable core 80, a cylindrical coil 8 is provided so as to straddle the two cores 78, 80.
4 are arranged. The coil 84 is supplied with a predetermined current from the drive circuit 62 based on a command from the control computer 57.

Next, the drive shaft 16 and the pulley 17
A power transmission mechanism provided between the power transmission device and the power transmission device will be described. As shown in FIGS. 1 and 2, the power transmission body 86 can be integrally rotated with the protruding end of the drive shaft 16 by a bolt 87 screwed to the tip of the drive shaft 16 via a disc spring 88 as a press-contact means. And is movably fastened in the axial direction. The power transmission member 86 is formed in a disk shape from an iron-based metal material, and has a boss 86a protruding at the center of the inner surface thereof, and an annular coupling portion 86b protruding at the outer periphery of the inner surface.

The interposition member 89 is fitted and supported on the boss portion 86a of the power transmission body 86 so as to be disposed between the opposed end faces of the power transmission body 86 and the pulley 17. This interposed member 89 is a disc-shaped elastic deformation plate 90 as an elastic deformation portion.
A plurality of connecting pins 91 as connecting portions protruding from the end face of the elastic deformation plate 90 on the pulley 17 side; and an annular friction material embedded in the end face of the elastic deformation plate 90 on the power transmission body 86 side. 92. The elastically deformable plate 90 includes a filler such as glass fiber, aramid fiber, alumina fiber, silicon carbide fiber, silicon carbide whisker, potassium titanate whisker, talc, mica, clay, etc., for example, polypropylene, polyamide, polyester , Polyacetal, polycarbonate, acrylic resin, AS resin, ABS resin, and an alloy resin of these resins. Also,
The coupling pin 91 is formed of an iron-based metal material, and is buried and fixed to the elastically deformable plate 90 at a small diameter portion 91a at a base end thereof.

Then, by the urging force of the disc spring 88,
The power transmission body 86 and the interposition member 89 are pressed toward the pulley 17 side. Thereby, the power transmission body 86
Is pressed and joined to the friction material 92 of the interposition member 89, so that the power transmission body 86 and the interposition member 89 are always frictionally connected. At the same time, each connecting pin 91 of the interposition member 89 is pressed against the end face of the pulley 17 made of an iron-based metal material, so that the interposition member 89 is always rotated integrally with the pulley 17.

When the load torque on the drive shaft 16 fluctuates while the rotation is transmitted from the pulley 17 to the drive shaft 16 via the interposition member 89 and the power transmission body 86, the rotation of the interposition member 89 The elastic deformation plate 90 is elastically deformed, so that the fluctuation of the load torque is reduced.

Further, when the load torque on the drive shaft 16 side becomes excessive, the connecting pin 91 of the interposition member 89
Relative sliding occurs at the pressure contact portion between the pulley 17 and the pulley 17 to generate frictional heat. This frictional heat is applied to the connecting pin 9
The elastically deformable plate 90 of the interposition member 89 is melted at a portion where the elastically deformable plate 90 of the interposition member 89 comes into contact with the small diameter portion 91a. Then, in the molten state of the elastically deformable plate 90, as shown by a chain line in FIG.
0 is formed on the side surface of the connecting pin 9
1 is relatively rotated with respect to the elastic deformation plate 90.

Next, the operation of the thus constructed clutchless variable displacement compressor will be described. When the detected temperature obtained from the room temperature sensor 59 is equal to or higher than the temperature set by the room temperature setter 58 with the air conditioner operation switch 60 turned on, the control computer 57 commands the excitation of the solenoid mechanism 65. . Then, a predetermined current is supplied to the coil 84 via the drive circuit 62, and as shown in FIG. 1, an attractive force corresponding to the input current value is generated between the iron cores 78 and 80. This suction force is a force in the direction in which the valve opening decreases in opposition to the urging force of the forcible opening spring 69, and is transmitted to the valve body 67 via the solenoid rod 83.

On the other hand, when the solenoid mechanism 65 is in the excited state, the bellows 73 is displaced in accordance with the fluctuation of the suction pressure Ps introduced from the suction passage 32 into the pressure sensing chamber 71 via the pressure detection passage 50. The displacement corresponding to the suction pressure Ps of the bellows 73 is transmitted to the valve body 67 via the pressure-sensitive rod 75. Accordingly, the valve opening of the displacement control valve 49 is determined by the balance between the urging force from the solenoid mechanism 65, the urging force from the bellows 73, and the urging force of the forcible opening spring 69.

When the cooling load is large, for example, the difference between the temperature detected by the room temperature sensor 59 and the temperature set by the room temperature setting device 58 becomes large. The control computer 57
The input current value is controlled so as to change the set suction pressure based on the detected temperature and the set room temperature. That is, the control computer 57 instructs the drive circuit 62 to increase the input current value as the detected temperature increases. Therefore, the attraction force between the fixed iron core 78 and the movable iron core 80 is increased, and the urging force in the direction of reducing the valve opening of the valve body 67 is increased. At a lower suction pressure Ps, the valve 67
Is opened and closed. Therefore, the capacity control valve 49 operates so as to maintain the lower suction pressure Ps by increasing the current value.

When the valve opening of the valve body 67 is reduced, the amount of refrigerant gas flowing from the discharge chamber 38 into the crank chamber 15 via the air supply passage 48 is reduced. On the other hand, the refrigerant gas in the crank chamber 15 flows out to the suction chamber 37 via the axial passage 46 and the pressure release port 47. Therefore, the pressure Pc in the crank chamber 15 decreases. In a state where the cooling load is large, the pressure in the cylinder bore 11a is also high,
The difference between the pressure Pc in the crank chamber 15 and the pressure in the cylinder bore 11a becomes smaller. For this reason, the inclination angle of the swash plate 22 increases.

When the passage cross-sectional area in the air supply passage 48 is zero, that is, when the valve body 67 of the capacity control valve 49 completely closes the valve hole 68, the supply of the high-pressure refrigerant gas from the discharge chamber 38 to the crank chamber 15 is performed. Will not be performed. Then, the pressure Pc in the crank chamber 15 becomes substantially the same as the pressure Ps in the suction chamber 37, and the inclination angle of the swash plate 22 becomes maximum. Swash plate 22
Is regulated by the contact between the inclination regulating protrusion 21a of the rotary support 21 and the swash plate 22, and the discharge capacity becomes maximum.

On the other hand, when the cooling load is small, for example, the temperature detected by the room temperature sensor 59 and the room temperature setting device 5
The difference from the set temperature of 8 becomes small. Control computer 5
7 instructs the drive circuit 62 to reduce the input current value as the detected temperature is lower. Therefore, the suction force between the fixed iron core 78 and the movable iron core 80 is weakened, and the urging force in the direction of reducing the valve opening of the valve body 67 is reduced. Then, the valve body 67 is opened and closed at a higher suction pressure Ps. Therefore, the capacity control valve 49 operates so as to maintain a higher suction pressure Ps by decreasing the current value.

When the valve opening of the valve body 67 increases, the amount of refrigerant gas flowing from the discharge chamber 38 into the crank chamber 15 increases, and the pressure Pc in the crank chamber 15 increases. When the cooling load is small, the pressure in the cylinder bore 11a is low, and the difference between the pressure Pc in the crank chamber 15 and the pressure in the cylinder bore 11a increases. For this reason, the inclination angle of the swash plate 22 becomes small.

As the cooling load is approached, the temperature in the evaporator 55 decreases so as to approach the temperature at which frost occurs. When the temperature detected by the temperature sensor 56 becomes equal to or lower than the set temperature, the control computer 57 instructs the drive circuit 62 to demagnetize the solenoid mechanism 65. The set temperature reflects a situation in which frost is likely to occur in the evaporator 55. Then, the supply of current to the coil 84 is stopped, the solenoid mechanism 65 is demagnetized, and the attractive force between the fixed iron core 78 and the movable iron core 80 disappears.

For this reason, as shown in FIG.
Is a follower spring 81 that acts via the movable iron core 80 and the solenoid rod 83 by the urging force of the forcible release spring 69.
Is moved downward against the urging force of And the valve body 67
Shifts to the valve opening position where the valve hole 68 is maximally opened. Therefore, a large amount of the high-pressure refrigerant gas in the discharge chamber 38 is supplied to the crank chamber 15 through the air supply passage 48, and the pressure Pc in the crank chamber 15 increases. Due to the pressure increase in the crank chamber 15, the inclination angle of the swash plate 22 shifts to the minimum inclination angle.

The control computer 57 instructs the demagnetization of the solenoid mechanism 65 based on the OFF signal of the air conditioner operation switch 60, and the inclination of the swash plate 22 also shifts to the minimum inclination by this demagnetization.

As described above, the opening / closing operation of the capacity control valve 49 changes according to the magnitude of the input current value to the coil 84. When the input current value increases, the opening and closing are performed at a low suction pressure Ps, and when the input current value decreases, the opening and closing operation is performed at a high suction pressure Ps. The compressor changes the inclination angle of the swash plate 22 so as to maintain the set suction pressure Ps, and changes the discharge capacity. That is, the capacity control valve 49
Has a role of changing the set value of the suction pressure Ps by changing the input current value and a role of performing the minimum displacement operation regardless of the suction pressure Ps. By providing such a capacity control valve 49, the compressor plays a role of changing the refrigeration capacity of the refrigeration circuit.

As the swash plate 22 moves toward the blocking body 28, the tilt of the swash plate 22 is transmitted to the blocking body 28 via the thrust bearing 34. By this tilt transmission, the interrupter 2
8 is moved to the positioning surface 33 side against the urging force of the suction passage opening spring 29. Here, the blocking body 28 gradually reduces the passage cross-sectional area of the suction passage 32. The throttle action due to the slow change of the cross-sectional area gradually reduces the amount of refrigerant gas flowing from the suction passage 32 into the suction chamber 37. For this reason, the amount of the refrigerant gas sucked into the cylinder bore 11a from the suction chamber 37 also gradually decreases, and the discharge capacity gradually decreases. Accordingly, the discharge pressure Pd gradually decreases, and the load torque in the compressor does not fluctuate greatly in a short time. As a result, the fluctuation of the load torque in the clutchless variable displacement compressor during the period from the maximum discharge capacity to the minimum discharge capacity becomes slow, and the impact due to the load torque fluctuation is reduced.

As shown in FIG. 3, when the inclination angle of the swash plate 22 is minimized, the blocking body 28 comes into contact with the positioning surface 33, and the suction passage 32 is blocked. In this state, the passage cross-sectional area in the suction passage 32 becomes zero, and the flow of the refrigerant gas from the external refrigerant circuit 52 into the suction chamber 37 is prevented. This swash plate 22
Is set to be a predetermined value slightly larger than 0 °. The minimum tilt state is determined by the
Is disposed at a closed position that blocks communication between the suction passage 32 and the accommodation hole 27. The blocking body 28 is switched between the closed position and the open position separated from the closed position in conjunction with the swing of the swash plate 22.

Since the minimum inclination angle of the swash plate 22 is not 0 °,
Even in the minimum tilt state, the refrigerant gas is discharged from the cylinder bore 11a to the discharge chamber 38. The refrigerant gas discharged from the cylinder bore 11a into the discharge chamber 38 flows into the crank chamber 15 through the air supply passage 48. The refrigerant gas in the crank chamber 15 flows into the suction chamber 37 through the shaft passage 46, the pressure release port 47, and the port 45. Inhalation chamber 37
Is sucked into the cylinder bore 11a,
It is discharged to the discharge chamber 38 again.

That is, in the state of minimum inclination, the discharge chamber 3
8, a circulation passage passing through the air supply passage 48, the crank chamber 15, the shaft passage 46, the pressure release passage 47, the housing hole 27, the passage 45, the suction chamber 37, and the cylinder bore 11a is formed in the compressor. . A pressure difference occurs between the discharge chamber 38, the crank chamber 15, and the suction chamber 37. Therefore, the refrigerant gas circulates in the circulation passage, and the lubricating oil flowing together with the refrigerant gas lubricates each sliding portion in the compressor.

With the air conditioner operation switch 60 in the ON state and the swash plate 22 in the minimum tilt position, when the temperature in the vehicle interior rises and the cooling load increases, the room temperature sensor 59
Temperature exceeds the set temperature of the room temperature setter 58. The control computer 57 commands excitation of the solenoid mechanism 65 based on the detected temperature change. By the excitation of the solenoid mechanism 65, the air supply passage 48 is closed, and the pressure Pc of the crank chamber 15 is reduced based on the pressure released through the shaft passage 46 and the pressure relief port 47. Due to this pressure reduction, the suction passage opening spring 29 extends from the contracted state in FIG. Then, the blocking body 28 is separated from the positioning surface 33, and the inclination angle of the swash plate 22 increases from the minimum inclination state in FIG.

With the separation of the blocking body 28, the suction passage 3
2, the passage cross-sectional area gradually increases, and the refrigerant gas inflow from the suction passage 32 to the suction chamber 37 gradually increases. Therefore, the amount of the refrigerant gas sucked into the cylinder bore 11a from the suction chamber 37 also gradually increases, and the discharge capacity gradually increases. Therefore, the discharge pressure Pd gradually increases, and the load torque in the compressor does not fluctuate greatly in a short time. As a result, the fluctuation of the load torque in the clutchless variable displacement compressor during the period from the minimum discharge capacity to the maximum discharge capacity becomes slow, and the impact due to the change in the load torque is reduced.

When the vehicle engine serving as the external drive source stops, the operation of the compressor also stops, that is, the rotation of the swash plate 22 stops, and the energization of the coil 84 of the displacement control valve 49 also stops. Therefore, the solenoid mechanism 65 is demagnetized, the air supply passage 48 is opened, and the inclination angle of the swash plate 22 is minimized.

Next, the drive shaft 16 and the pulley 17
The operation of the power transmission mechanism installed between the power transmission mechanism and the power transmission mechanism will be described. Now, in this power transmission mechanism, the coupling portion 86b of the power transmission body 86 is frictionally coupled to the friction material 92 of the interposition member 89 by the urging force of the disc spring 88, and the connection pins 91 of the interposition member 89 are connected. Is pressed against the end face of the pulley 17. For this reason, when the pulley 17 is constantly rotated via the belt 18 by the vehicle engine as an external drive source, the rotation is transmitted to the drive shaft 16 via the interposition member 89 and the power transmission body 89, and the compression is performed. The machine is operated for compression.

When the load torque on the compressor side fluctuates during the operation of the compressor, the elastic deformation plate 90 of the interposition member 89 is elastically deformed, and the fluctuation of the load torque is reduced. Therefore, the fluctuation of the load torque on the compressor side does not spread to the vehicle engine side as the external drive source, and the fluctuation of the rotation speed of the vehicle engine can be suppressed.

If the load torque on the compressor side is excessive, relative sliding occurs at the press contact portion between the connecting pin 91 of the interposition member 89 and the pulley 17, and frictional heat is generated. And
This frictional heat is transmitted to the elastically deformable plate 90 through each connecting pin 91, and the elastically deformable plate 90 is melted near the small diameter portion 91 a of the connecting pin 91. In the molten state of the elastically deformable plate 90, as shown by a chain line in FIG. 2, the idling groove 93 is formed on the side surface of the elastically deformable plate 90 by the small-diameter portion 91 a of the connecting pin 91. It is rotated relative to the elastically deformable plate 90 in the idling groove 93. This allows
Transmission of the overload torque from the drive shaft 16 to the pulley 17 is cut off, so that adverse effects on the vehicle engine can be suppressed.

The effects that can be expected from the above embodiment will be described below. (A) In the power transmission mechanism of the clutchless variable displacement compressor of this embodiment, when the load torque on the drive shaft 16 fluctuates, the elastic deformation plate 90 of the interposition member 89 made of a thermoplastic resin material is elastically deformed. It is supposed to. Further, when the load torque on the drive shaft 16 side becomes excessive, relative sliding occurs at the press contact portion between the interposition member 89 and the pulley 17, and frictional heat is generated. Is melted. For this reason, despite the simple structure, the fluctuation of the load torque on the compressor side can be effectively mitigated, and the transmission of the overload torque to the vehicle engine serving as the external drive source is reliably shut off. be able to.

(B) In the power transmission mechanism of the clutchless variable displacement compressor of this embodiment, the elastic deformation plate 90 of the interposition member 89 is formed of a thermoplastic resin material. For this reason, even when the compressor is used in a low-temperature environment such as a cold region, a change in elasticity of the elastically deformable plate 90 can be suppressed to be small. Therefore, the elastic deformation plate 90 cannot effectively reduce the fluctuation of the load torque in a low temperature environment,
Even if it is not a large load torque, it is possible to suppress breakage inadvertently.

(C) In the power transmission mechanism of the clutchless variable displacement compressor of this embodiment, when the load torque on the compressor side becomes excessive,
Relative sliding occurs at the press contact portion between the pulley 1 and the pulley 17 to generate frictional heat. For this reason, the frictional heat is transmitted from the connecting pin 91 to the elastically deformable plate 90, and the elastically deformable plate 90 is melted near the small diameter portion 91 a of the connecting pin 91. It will be rotated relatively. Therefore, transmission of the overload torque from the drive shaft 16 to the pulley 17 can be reliably shut off.

(D) In the power transmission mechanism of the clutchless variable displacement compressor according to this embodiment, the connecting pin 91 of the interposition member 89 is formed of an iron-based metal material having high thermal conductivity and rigidity. For this reason, in particular, in the configuration of the above-described embodiment in which the connecting pin 91 of the interposition member 89 is pressed against the pulley 17 made of a metal material, the frictional heat caused by the relative sliding of the pressing portion causes the elastically deformable plate Thus, the elastically deformable plate 90 can be quickly melted. Therefore, transmission of the overload torque from the drive shaft 16 to the pulley 17 can be quickly and reliably interrupted.

(E) In the power transmission mechanism of the clutchless variable displacement compressor of this embodiment, the elastic deformation plate 90 of the interposition member 89 is made of a thermoplastic resin material containing a filler. For this reason, the strength of the elastic deformation plate 90 is improved by the reinforcing effect of the filler, and the occurrence of inadvertent power transmission interruption with a small load torque is suppressed.

(Second Embodiment) Next, a second embodiment of the present invention will be described.
The second embodiment will be described focusing on the differences from the first embodiment.

In the power transmission mechanism of the second embodiment, as shown in FIG.
Are projected from the end face of the elastic deformation plate 90 on the power transmission body 86 side, and the friction material 92 is connected to the pulley 17 of the elastic deformation plate 90.
Buried in the side end face. An annular coupling portion 96 is formed on the end face of the pulley 17 so as to protrude. And
The urging force of the disc spring 88 causes the friction member 92 of the
Is frictionally coupled to the coupling portion 96 of the pulley 17,
The connecting pin 91 of the interposition member 89 is pressed against the connecting portion 86 b of the power transmission body 86.

Therefore, also in the second embodiment,
In substantially the same manner as in the first embodiment described above, when the load torque on the compressor side fluctuates during operation of the compressor, the interposition member 89
The elastically deformable plate 90 is elastically deformed, and the fluctuation of the load torque is reduced. Therefore, the fluctuation of the load torque on the compressor side spreads to the vehicle engine side as an external drive source,
Fluctuations in the rotational speed of the vehicle engine can be suppressed.

If the load torque on the compressor side becomes excessive, relative sliding occurs at the press contact portion between the connecting pin 91 of the interposition member 89 and the power transmission body 86, and frictional heat is generated. Then, the frictional heat is transmitted through each connecting pin 91 to the elastically deformable plate 9
0, and the elastically deformable plate 90 is melted in the vicinity of the small diameter portion 91a of the connecting pin 91. In the molten state of the elastically deformable plate 90, the idling groove 93 is formed on the side surface of the elastically deformable plate 90 by the small diameter portion 91 a of the connecting pin 91, and thereafter the connecting pin 91 is relatively rotated with respect to the elastically deformable plate 90. . Thus, the transmission of the overload torque from the drive shaft 16 to the pulley 17 is cut off, so that adverse effects on the vehicle engine can be suppressed.

(Third Embodiment) Next, a third embodiment of the present invention will be described.
The second embodiment will be described focusing on the differences from the first embodiment.

In the power transmission mechanism of the third embodiment, as shown in FIG. 5, a plurality of fitting recesses 97 are formed on the end surface of the pulley 17, and these fitting recesses 97 are provided with interposition members. The connecting pins 91 of the 89
And the pulley 17 are integrally rotatably connected. A rough pressing surface 98 is formed on a surface of the coupling portion 86b of the power transmission body 86 facing the elastically deformable plate 90. The urging force of the disc spring 88 causes the pressure contact surface 9 to move.
8 is pressed against the elastic deformation plate 90.

Therefore, also in the third embodiment,
In substantially the same manner as in the first embodiment described above, when the load torque on the compressor side fluctuates, the elastic deformation plate 90 of the interposition member 89 is elastically deformed, and the fluctuation of the load torque is alleviated. Spread of the torque fluctuation to the engine side is suppressed.

Further, when the load torque on the compressor side becomes excessive, relative sliding occurs at the press contact portion between the elastic deformation plate 90 of the interposition member 89 and the press contact surface 98 of the power transmission body 86, and friction occurs. Heat is generated. Then, the portion of the elastically deformable plate 90 facing the pressure contact surface 98 is melted by the frictional heat, and the transmission of the overload torque from the drive shaft 16 to the pulley 17 is cut off. Therefore, it is possible to prevent the overload torque on the compressor side from adversely affecting the vehicle engine.

Further, after the overload torque on the compressor side calms down and the heat generation of the press contact portion is reduced, the intervening member 8
The portion of the elastic deformation plate 90 facing the pressure contact surface 98 is re-solidified from the molten state. Therefore, it is not necessary to replace the intervening member 89 with a new one, and the power transmission from the pulley 17 to the drive shaft 16 can be restarted.

(Fourth Embodiment) Next, a fourth embodiment of the present invention will be described.
The second embodiment will be described focusing on the differences from the first embodiment.

In the power transmission mechanism according to the fourth embodiment, as shown in FIG. 6, the elastically deformable plate 90 of the interposition member 89 is rotatable integrally with the protruding end of the drive shaft 16 and has an axial line. It is connected and fixed so that it can move in the direction. The elastic deformation plate 90 also serves as a power transmission body. Further, this interposed member 89 is a disc spring 88
Thus, the connection pin 91 of the interposition member 89 is pressed against the end face of the pulley 17.

Therefore, also in the fourth embodiment,
In substantially the same manner as in the first embodiment, when the load torque on the compressor side fluctuates, the elastic deformation plate 90 of the interposition member 89 is elastically deformed, and the fluctuation of the load torque is reduced. Further, when the load torque becomes excessive, relative sliding occurs at the press contact portion between the connecting pin 91 and the pulley 17, and frictional heat is generated. The transmission of the load torque is interrupted. Therefore,
Almost the same effects as in the first embodiment can be achieved.

Further, in the fourth embodiment,
An elastic deformation plate 90 of the interposition member 89 is fixedly connected to the drive shaft 16 so as to double as a power transmission body. For this reason, it is not necessary to separately provide a power transmission body on the drive shaft 16, so that the number of parts can be reduced and the weight of the compressor can be reduced.

The present invention can be embodied with the following modifications. (1) In the power transmission mechanism of each of the above embodiments, the connecting portion of the interposition member 89 is formed in an annular shape from an iron-based metal material, and a plurality of pins projecting from the back surface are embedded in the elastically deformable plate 90. To be configured.

(2) In the power transmission mechanism of each of the above-described embodiments, an urging member different from the disc spring 88 is provided as the pressure contact means. (3) In the third embodiment, the power transmission body 86
A fitting recess 97 is provided on the upper side, and the connecting pin 91 of the interposition member 89 is provided.
Into the fitting recess 97 and the pulley 17
A rough pressing surface 98 is formed on the surface of the interposition member 89 facing the elastic deformation plate 90, and the pressing surface 98 of the pulley 17 is pressed against the elastic deformation plate 90.

Even with such a configuration, substantially the same operation and effect as those of the above embodiments can be obtained.

[0101]

The present invention is configured as described above, and has the following effects. According to the first aspect of the present invention, when the load torque on the drive shaft side fluctuates, the elastically deformable portion of the interposed member made of a thermoplastic resin material is elastically deformed. Further, when the load torque on the drive shaft side becomes excessive, relative sliding occurs at the press contact portion between the interposition member and the drive shaft or the pulley, and frictional heat is generated, and the frictional heat of the interposition member is generated by the frictional heat. The elastically deformed portion is melted. Therefore, despite the simple structure, fluctuations in load torque on the compressor side can be effectively mitigated without deteriorating even in a low-temperature environment, and transmission of overload torque is ensured. Can be shut off.

According to the second aspect of the present invention, when the load torque on the compressor side becomes excessive, relative sliding occurs at the press contact portion between the connection portion of the interposition member and the power transmission body or the pulley. As a result, frictional heat is generated. Thereby, the frictional heat is transmitted from the connecting portion to the elastically deforming portion of the interposition member, the elastically deforming portion is melted, and thereafter, the connecting portion is rotated relative to the elastically deforming portion. Therefore, transmission of the overload torque from the drive shaft to the pulley can be reliably shut off.

According to the third aspect of the present invention, when the load torque on the compressor side is excessive, the relative sliding between the elastically deforming portion of the interposition member and the pressure contact portion between the power transmission body or the pulley. Is generated and frictional heat is generated. Thereby, the vicinity of the pressure contact portion of the elastic deformation portion is melted, and transmission of the overload torque from the drive shaft to the pulley is cut off. For this reason, after the overload torque on the compressor side has calmed down and the heat generation of the press contact portion has subsided, the vicinity of the press contact portion of the elastic deformation portion of the interposition member is re-solidified from a molten state, and power transmission is restarted. Can be.

According to the fourth aspect of the present invention, the elastically deforming portion of the interposition member is fixedly connected to the drive shaft so as to double as the power transmission body. Therefore, it is not necessary to separately provide a power transmission body on the drive shaft, so that the number of parts can be reduced and the weight of the compressor can be reduced.

According to the fifth aspect of the present invention, the connecting portion of the interposition member is formed of an iron-based metal material having high thermal conductivity and rigidity. For this reason, the frictional heat accompanying the relative sliding of the press contact portion is quickly transmitted from the connecting portion to the elastically deformable portion of the interposition member, and the elastically deformable portion can be quickly melted. Therefore, transmission of the overload torque from the drive shaft to the pulley can be quickly and reliably interrupted.

According to the sixth aspect of the invention, the elastically deformable portion of the interposition member is made of a thermoplastic resin material containing a filler. For this reason, the strength of the elastic deformation portion is improved, and it is possible to suppress the occurrence of inadvertent power transmission interruption with a small load torque.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a clutchless variable displacement compressor including a power transmission mechanism according to a first embodiment in a maximum tilt state;

FIG. 2 is a sectional view taken along line 2-2 in FIG. 1;

FIG. 3 is a cross-sectional view showing the compressor of FIG. 1 in a minimum tilt state;

FIG. 4 is a partial cross-sectional view illustrating a power transmission mechanism according to a second embodiment.

FIG. 5 is a partial cross-sectional view illustrating a power transmission mechanism according to a third embodiment.

FIG. 6 is a partial cross-sectional view illustrating a power transmission mechanism according to a fourth embodiment.

[Explanation of symbols]

16 drive shaft, 17 pulley, 18 belt, 8
6 ... power transmission body, 89 ... interposed member, 90 ... elastic deformation plate as elastic deformation part, 91 ... connection pin as connection part.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Masakazu Murase 2-1-1 Toyota-cho, Kariya-shi, Aichi Pref. Inside Toyota Industries Corporation (72) Inventor Tetsuhiko Fukanuma 2-1-1 Toyota-cho, Kariya-shi, Aichi Pref. Inside Toyota Industries Corporation (72) Inventor Yuji Kubo 2-1-1 Toyota-cho, Kariya City, Aichi Prefecture Inside Toyota Industries Corporation

Claims (6)

[Claims] 1. A clutchless variable displacement compressor in which an external drive source and a drive shaft are constantly operatively connected via a belt and a pulley, wherein a connection portion made of a metal material is provided between the drive shaft and the pulley. An interposed member having an elastically deformable portion made of a thermoplastic resin material is disposed, and the interposed member is coupled to one of the drive shaft and the pulley, and is always rotatable integrally with the other. When the load torque on the drive shaft side fluctuates, the elastic deformation portion of the interposition member is elastically deformed, and when the load torque on the drive shaft side becomes excessive, the frictional heat caused by the relative sliding of the press contact portion causes ,
A power transmission mechanism of a clutchless variable displacement compressor in which an elastic deformation portion of an interposition member is melted. 2. A power transmission body is fixed to the drive shaft, an interposition member is disposed between the end faces of the power transmission body and the pulley, and a connection portion of the interposition member is made of a metal material. The power transmission mechanism for a clutchless variable displacement compressor according to claim 1, wherein the power transmission mechanism is pressed against a transmission body or a pulley made of a metal material. 3. A power transmission body is fixed to the drive shaft, an interposition member is disposed between the opposing end faces of the power transmission body and the pulley, and an elastic deformation portion of the interposition member is made of a metal material. The power transmission mechanism for a clutchless variable displacement compressor according to claim 1, wherein the power transmission mechanism is pressed against a power transmission body or a pulley made of a metal material. 4. The power transmission mechanism for a clutchless variable displacement compressor according to claim 1, wherein the elastically deformable portion of the interposition member is fixedly connected to a drive shaft to serve also as a power transmission body. 5. The power transmission mechanism for a clutchless variable displacement compressor according to claim 1, wherein the connecting portion of the interposition member is formed of an iron-based metal material. 6. The power transmission mechanism for a clutchless variable displacement compressor according to claim 1, wherein the elastically deformable portion of the interposition member is made of a thermoplastic resin material containing a filler.