JPH10266954A - Control valve for variable displacement compressor and assembling method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control valve for a variable displacement compressor that is able to determine the initial setting position of a pressure sensitive member in a simple structure without incurring any possible expandization as a whole, and also to reduce the cost of production jointly. SOLUTION: A cap member 84 is fitted in a cylinder 85 projectingly installed in the tip of a body 83, partitively forming a pressure sensitive chamber 68. A pressure sensitive member 70 transmitting a variation in suction pressure to a valve element 64 is housed in this pressure sensitive chamber 68. Here, in a state that the specified pressure is made to act on the inside of the pressure sensitive chamber 68, the extent of fitting length between the cylinder 85 and the cap member 84 is adjusted, determining an initial setting position of the pressure sensitive member 70. Subsequently, the cap member 84 is clamped tight to the cylinder 85 by means of caulking or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control valve for a variable displacement compressor used in, for example, a vehicle air conditioner.

[0002]

2. Description of the Related Art Conventionally, as a variable capacity compressor, for example, a configuration described in Japanese Patent Application Laid-Open No. Hei 7-18059 is known. In this variable displacement compressor, a displacement control valve is disposed in the middle of an air supply passage between a discharge region and a crank chamber that also serves as a control pressure chamber, and the opening of the displacement control valve is applied to a cooling load in a vehicle compartment. It is controlled based on. By adjusting the opening of the displacement control valve, the supply amount of the high-pressure compressed refrigerant gas from the discharge region to the crank chamber is changed, and the pressure in the crank chamber is raised and lowered. Then, based on the rise and fall of the pressure in the crank chamber, the difference between the pressure in the crank chamber and the pressure in the cylinder bore is changed. Then, the inclination angle of the cam plate is changed according to this difference, so that the discharge capacity is adjusted.

The displacement control valve used in the conventional variable displacement compressor has the following configuration. That is, a valve body including a reed valve for opening and closing the air supply passage is provided on the valve plate. At a position on the rear housing corresponding to the valve body, a pressure-sensitive chamber connected to the suction area is formed. A bellows that expands and contracts according to the pressure in the suction area, that is, the fluctuation of the suction pressure is disposed in the pressure-sensitive chamber. The bellows and the valve element are connected via a pressure-sensitive rod, and the valve element is moved in accordance with expansion and contraction of the bellows, so that the air supply passage is opened and closed. The pressure sensing chamber is opened to the outside of the rear housing, and the inner peripheral surface of the opening is a screw hole. An adjusting screw member is screwed into the opening, and an initial setting position of the bellows is determined by a screwing position of the adjusting screw member.

[0004]

However, in this conventional control valve for a variable displacement compressor, a screw hole is formed in the opening of the pressure-sensitive chamber and a screw portion corresponding to the outer peripheral surface of the adjusting screw member. Need to be formed. For this reason, the shape of the component becomes complicated, processing and assembling are troublesome, and the production cost is increased.

In order to determine the initial position of the bellows by screwing the pair of screw portions, it is necessary to secure the screw portion of a predetermined length and to adjust the adjusting screw member to the adjusting screw member. It is necessary to provide a jig mounting part for tightening the jig. For this reason, there is a possibility that the size of the adjusting screw member is increased, and eventually the size of the entire control valve is increased.

The present invention has been made by paying attention to such problems existing in the conventional technology. Its purpose is to be able to determine the initial setting position of the pressure-sensitive member with a simple configuration without increasing the overall size,
An object of the present invention is to provide a control valve for a variable displacement compressor capable of reducing manufacturing costs.

[0007]

In order to achieve the above object, according to the first aspect of the present invention, the discharge capacity is changed by opening and closing a passage connecting a suction area or a discharge area to a control pressure chamber. In the control valve of the variable displacement compressor,
A valve chamber connected to the passage through the valve hole, a valve body housed in the valve chamber to open and close the valve hole, and a sensor connected to the suction area or the control pressure chamber through the pressure detection passage. A pressure mechanism and a pressure-sensitive member housed in the pressure-sensitive mechanism, configured to be displaced according to the pressure of the suction area or the control pressure chamber, and connected to the valve body via a pressure-sensitive rod. Prepared,
A part of the peripheral wall of the pressure-sensitive mechanism is constituted by a cylinder and a cap member, and the cap member is fitted to the cylinder and fixed at a predetermined position to determine an initial setting position of the pressure-sensitive member. It was done.

According to a second aspect of the present invention, there is provided a control valve for a variable displacement compressor which changes a discharge capacity by opening and closing a passage connecting a suction area or a discharge area and a control pressure chamber. A valve chamber connected to the passage through the valve chamber, a valve element housed in the valve chamber and opening and closing the valve hole, a solenoid portion connected to the valve element via a solenoid rod, and the suction area or A pressure-sensitive mechanism connected to the control pressure chamber via a pressure detection passage, and housed in the pressure-sensitive mechanism, configured to be displaced in accordance with the pressure of the suction area or the control pressure chamber; A pressure-sensitive member connected via a pressure-sensitive rod, a part of the peripheral wall of the pressure-sensitive mechanism is constituted by a cylinder and a cap member, and the cap member is fitted to the cylinder and fixed at a predetermined position. To determine the initial setting position of the pressure-sensitive member In which was to so that.

According to a third aspect of the present invention, there is provided a control valve of a variable displacement compressor which changes a discharge capacity by opening and closing a passage communicating a suction area or a discharge area with a control pressure chamber. A valve chamber connected to the passage through the valve hole, a valve body housed in the valve chamber to open and close the valve hole, and a sensor connected to the suction area or the control pressure chamber through the pressure detection passage. A pressure mechanism and a pressure-sensitive member housed in the pressure-sensitive mechanism, configured to be displaced according to the pressure of the suction area or the control pressure chamber, and connected to the valve body via a pressure-sensitive rod. In the method for assembling a control valve for a variable displacement compressor, a part of the peripheral wall of the pressure-sensitive mechanism is constituted by a cylinder and a cap member, and the cap member is fitted to the cylinder to form the pressure-sensitive mechanism. In a state where a predetermined pressure is applied to the pressure-sensitive chamber inside, the pressure-sensitive member To be placed in a fixed position, after adjusting the engagement length between the cylinder and the cap member is for fixing the cap member relative to the tubular body.

According to a fourth aspect of the present invention, there is provided a control valve of a variable displacement compressor which changes a discharge capacity by opening and closing a passage communicating a suction area or a discharge area with a control pressure chamber. A valve chamber connected to the passage via a valve hole, a valve element housed in the valve chamber, and opening and closing the valve hole; a solenoid portion connected to the valve element via a solenoid rod; A pressure-sensitive mechanism connected to an area or a control pressure chamber via a pressure detection passage, and a valve housed in the pressure-sensitive mechanism and configured to be displaced in accordance with the pressure of the suction area or the control pressure chamber; In a method for assembling a control valve for a variable displacement compressor having a pressure-sensitive member connected to a body via a pressure-sensitive rod, a part of the peripheral wall of the pressure-sensitive mechanism is constituted by a cylinder and a cap member, Fit the cap member to the cylinder,
While supplying a predetermined current to the coil of the solenoid unit,
The fitting length of the cylinder and the cap member is adjusted so that the pressure-sensitive member is disposed at a predetermined initial setting position while a predetermined pressure is applied to the pressure-sensitive chamber in the pressure-sensitive mechanism. After that, the cap member is fixed to the cylindrical body.

Therefore, according to the first and third aspects of the present invention, the fitting length between the cylindrical body and the cap member is adjusted while a predetermined pressure is supplied to the pressure-sensitive chamber accommodating the pressure-sensitive member. By fixing the cap member to the cylinder, the initial setting position of the pressure-sensitive member is determined. For this reason, the shapes of the cylindrical body and the cap member can be simplified, and the initial setting position of the pressure-sensitive member can be easily determined.

According to the second and fourth aspects of the present invention, the cylinder and the cap are supplied while a predetermined pressure is supplied to the pressure-sensitive chamber accommodating the pressure-sensitive member while a predetermined current is supplied to the coil of the solenoid portion. The initial setting position of the pressure-sensitive member is determined by adjusting the fitting length with the member and fixing the cap member to the cylinder. For this reason, the shapes of the cylindrical body and the cap member can be simplified, and the initial setting position of the pressure-sensitive member can be easily determined.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) A first embodiment in which the present invention is embodied in a displacement control valve of a clutchless variable displacement compressor will be described below with reference to FIGS.

First, the configuration of the clutchless variable displacement compressor will be described. As shown in FIG. 2, a front housing 12 is joined to a front end of the cylinder block 11. A rear housing 13 is joined and fixed to the rear end of the cylinder block 11 via a valve plate 14. Front housing 12 and cylinder block 11
Between them, a crank chamber 15 also serving as a control pressure chamber is formed, and a drive shaft 16 is rotatably supported.

The front end of the drive shaft 16 projects from the crank chamber 15 to the outside, and a pulley 17 is fixed to the projected end. The pulley 17 is constantly operatively connected to a vehicle engine (not shown) via a belt 18. The pulley 17 is supported by the front housing 12 via an angular bearing 19. The front housing 12 receives both the axial load and the radial load acting on the pulley 17 via the angular bearing 19.

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

The drive shaft 16 is provided with the crank chamber 1.
In 5, a rotation support 21 is fixed, and a swash plate 22 forming a cam plate is supported so as to be slidable and tiltable 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, and the support arm 24 has a pair of guide holes 25 formed therein. Guide pin 2
3 is slidably fitted in the guide hole 25.
By the cooperation between the support arm 24 and the pair of guide pins 23, 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.

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. An inclination reducing spring 26 is interposed between the rotary support 21 and the swash plate 22.
The inclination reducing spring 26 biases the swash plate 22 in a direction in which the inclination decreases. In addition, on the rear surface of the rotary support 21,
An inclination restricting projection 21 for restricting the maximum inclination of the swash plate 22
a is formed.

As shown in FIGS. 2 to 4, a housing hole 27 is formed in the center of the cylinder block 11 in the drive shaft 1.
6 in the axial direction. A cylindrical blocking body 28 is slidably accommodated in the accommodation hole 27. The blocking body 28 includes a large diameter portion 28a and a small diameter portion 28b. A suction passage opening spring 29 is interposed between the step between the large diameter portion 28a and the small diameter portion 28b and the end face of the housing hole 27. The suction passage opening spring 29 urges the blocking body 28 toward the swash plate 22.

The rear end of the drive shaft 16 is inserted into the cylinder of the blocking body 28. A radial bearing 30 is fitted and supported on the inner peripheral surface of the large diameter portion 28a.
The radial bearing 30 is prevented from falling out of the cylinder of the blocking body 28 by a circlip 31 attached to the inner peripheral surface of the large diameter portion 28a. 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.

In the center of the rear housing 13, there is formed a suction passage 32 forming a suction area. The suction passage 32 is on an extension of the drive shaft 16 which is a movement path of the blocking body 28. The suction passage 32 communicates with 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. Positioning surface 33
Is on the valve plate 14. The distal end face of the small diameter portion 28 b of the blocking body 28 can abut on the positioning surface 33.
When the distal end surface of the small diameter portion 28b abuts on the positioning surface 33, the backward movement of the blocking body 28 is restricted.

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 thrust bearing 34 is always sandwiched between the swash plate 22 and the end face of the large diameter portion 28 a of the blocking body 28 by the urging force of the suction passage opening spring 29.

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 moves to the positioning surface 33 side against the urging force of the suction passage opening spring 29, and the blocking body 28 contacts the positioning surface 33. The rotation of the swash plate 22 is prevented from being transmitted to the interrupter 28 by the presence of the thrust bearing 34.

As shown in FIG. 2, a single-headed piston 35 is accommodated in a plurality of cylinder bores 11a provided through the cylinder block 11. The rotational movement of the swash plate 22 is converted into a reciprocating swing of the piston 35 via the shoe 36, whereby the piston 35 is moved back and forth in the cylinder bore 11a.

In the rear housing 13, a suction chamber 37 forming a suction area and a discharge chamber 3 forming a discharge area are provided.
8 are sectioned. On the valve plate 14,
A suction port 39 and a discharge port 40 are formed, and a suction valve 41 and a discharge valve 42 are formed so as to correspond to the suction port 39 and the discharge port 40. Here, due to the reciprocating operation of the piston 35 from the top dead center position to the bottom dead center position, the refrigerant gas in the suction chamber 37 pushes back the suction valve 41 from the suction port 39 and the cylinder bore 11a
Flows into the interior. The refrigerant gas flowing into the cylinder bore 11a is compressed by the forward movement of the piston 35 from the bottom dead center position to the top dead center position until a predetermined pressure is reached. Then, the compressed refrigerant gas is discharged from the discharge port 40 to the discharge chamber 38 by pushing the discharge valve 42 away. At this time, the opening of the discharge valve 42 is regulated by contacting the retainer 43.

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

As shown in FIG. 2 to FIG.
Communicates with the accommodation hole 27 through the opening 45. When the blocking body 28 contacts the positioning surface 33, the suction passage 32
Is closed, and the opening 45 is shut off from the suction passage 32. An axial passage 46 is formed in the drive shaft 16. The inlet 46a of the axial passage 46 is open to the crank chamber 15 near the lip seal 20, and the axial passage 4
The outlet 46b of the opening 6 opens into the cylinder of the blocking body 28. A pressure release port 47 is provided through the peripheral surface of the blocking body 28.
The pressure release port 47 communicates the inside of the cylinder of the blocking body 28 with the housing hole 27.

The discharge chamber 38 and the crank chamber 15 are connected to an air supply passage 4 as a passage connecting the discharge region and the control pressure chamber.
8 communicates. In the middle of the air supply passage 48, a capacity control valve 49 as a control valve for opening and closing the air supply passage 48 is provided. Further, between the suction passage 32 and the displacement control valve 49, a pressure detection passage 50 for guiding the suction pressure Ps into the displacement control valve 49 is formed.

The suction passage 32 serving as an inlet for introducing refrigerant gas into the suction chamber 37 and a discharge flange 51 for discharging refrigerant gas from the discharge chamber 38 are connected by an external refrigerant circuit 52. On the external refrigerant circuit 52, the condenser 5
3. The expansion valve 54 and the evaporator 55 are interposed. A temperature sensor 56 is provided near the evaporator 55.
The temperature sensor 56 detects the temperature in the evaporator 55,
This detected temperature information is sent to the control computer 57.
Further, the control computer 57 is connected to a room temperature setting device 58 for specifying the temperature in the cabin of the vehicle, a room temperature sensor 58a, an air conditioner operation switch 59 and the like.

Then, the control computer 57, for example, controls the room temperature specified by the room temperature setting unit 58 in advance, the detected temperature obtained from the temperature sensor 56, the detected temperature obtained from the room temperature sensor 58a, and the ON state of the air conditioner operation switch 59. Alternatively, an input current value is instructed to the drive circuit 60 based on an external signal such as an off signal. The driving circuit 60
The instructed input current value is output to the coil 82 of the solenoid unit 62 of the displacement control valve 49 described later. Other external signals include, for example, signals from an outdoor temperature sensor, an engine speed, and the like, and the input current value is determined according to the environment of the vehicle.

Next, the displacement control valve 49 as the control valve for the variable displacement compressor of this embodiment will be described in detail. As shown in FIGS. 1 to 4, the capacity control valve 49 is configured by joining a valve housing 61 and a solenoid portion 62 near the center. A valve chamber 63 is defined between the valve housing 61 and the solenoid 62,
A valve body 64 is accommodated in the valve chamber 63. Valve chamber 63
A valve hole 66 is opened so as to face the valve body 64. The valve hole 66 is formed to extend in the axial direction of the valve housing 61. Valve body 64 and valve chamber 63
A forced release spring 65 is interposed between the inner wall surface of the valve body and the valve body 64 to urge the valve body 64 in the opening direction of the valve hole 66. The valve chamber 63 includes a valve chamber port 67 and the air supply passage 48.
Through the discharge chamber 38 in the rear housing 13.

At the tip of the valve housing 61,
A pressure-sensitive chamber 68 is defined. This pressure-sensitive chamber 68
The suction port 32 of the rear housing 13 communicates with the pressure detection port 69 and the pressure detection passage 50. Pressure sensing chamber 6
A bellows 70 as a pressure-sensitive member is accommodated in the inside of the tube 8. A pressure-sensitive rod guide 71 that is continuous with the valve hole 66 is formed between the pressure-sensitive chamber 68 and the valve chamber 63. The pressure-sensitive rod 72 is slidably inserted into the pressure-sensitive rod guide 71, and its tip is inserted into the connection part 70 a of the bellows 70. The bellows 70 and the valve body 64 are operatively connected to each other via the pressure-sensitive rod 72 so as to be able to come and go. That is, these pressure-sensitive chambers 6
The bellows 70, the pressure-sensitive rod guide 71, and the pressure-sensitive rod 72 constitute a pressure-sensitive mechanism that transmits the fluctuation of the suction pressure Ps to the valve body 64. The portion of the pressure-sensitive rod 72 on the valve body 64 side has a small diameter in order to secure a passage for the refrigerant gas in the valve hole 66.

A valve chamber 63 is provided in the valve housing 61.
A port 74 is formed between the pressure sensing chamber 68 and the pressure sensing chamber 68 so as to be orthogonal to the valve hole 66. Port 74 is
It is communicated with the crank chamber 15 through an air supply passage 48.

The solenoid section 62 includes a solenoid chamber 7.
A fixed core 76 is fitted into the upper opening of the partition 7. In the solenoid chamber 77, a movable iron core 78 having a substantially closed cylindrical shape is accommodated so as to be able to reciprocate. A follow-up spring 79 is interposed between the movable iron core 78 and the bottom of the solenoid chamber 77. Note that this follower spring 79
The elastic coefficient is smaller than that of the forcible opening spring 65.

The fixed iron core 76 has a solenoid chamber 77
Rod guide 8 that communicates with the valve chamber 63
0 is formed. The solenoid rod 81 is formed integrally with the valve body 64, and is slidably inserted into the solenoid rod guide 80. Further, the end of the solenoid rod 81 on the movable iron core 78 side is moved by the urging force of the forcible opening spring 65 and the follower spring 79.
Is in contact with The movable core 78 and the valve 6
4 are operatively connected via a solenoid rod 81.

Outside the fixed iron core 76 and the movable iron core 78, a cylindrical coil 82 is provided so as to straddle both the iron cores 76 and 78.
Is arranged. The coil 82 is supplied with a predetermined current from the drive circuit 60 based on a command from the control computer 57.

The displacement control valve 4 of the first embodiment will now be described.
9, the valve housing 61 includes a main body 83 and a cap member 84. The main body 83 has one end joined to the solenoid portion 62 and a cylindrical body 85 projecting from the other end. A cap member 84 is fitted on the outer peripheral surface of the cylindrical body 85. The cap member 84 has a role of determining an initial setting position of the bellows 70 by adjusting a fitting length with the cylindrical body 85. In this state, the cap member 84 is fixed to the cylindrical body 85 by caulking. The pressure-sensitive chamber 68 is defined by the main body 83 and the cap member 84. That is, the cylindrical body 85 and the cap member 84 constitute a part of the peripheral wall of the pressure-sensitive mechanism.

Next, the capacity control valve 4 of the first embodiment
A method of assembling the pressure-sensitive mechanism 9 will be described. First, the bellows 70 is housed in the cap member 84. Then, the cap member 84 is fitted to the outer peripheral surface of the cylindrical body 85 of the main body 83 while the connecting portion 70a of the bellows 70 and the pressure-sensitive rod 72 are fitted so as to be relatively movable.

Next, a predetermined current is supplied to the coil 82 of the solenoid unit 62 to generate an attractive force between the fixed iron core 76 and the movable iron core 78 according to the input current value. This suction force acts on the valve body 64 via the solenoid rod 81. At the same time, when a predetermined pressure is supplied to the pressure-sensitive chamber 68 via the pressure detection port 69, the bellows 70 in the pressure-sensitive chamber 68 is displaced in accordance with the pressure in the pressure-sensitive chamber 68. This displacement is transmitted to the valve body 64 via the pressure-sensitive rod 72. That is, in this state, the urging force from the solenoid portion 62, the urging force from the bellows 70, and the urging force from the forcible opening spring 65 act on the valve body 64. Then, the opening of the valve hole 66 by the valve body 64 is adjusted according to the balance of these urging forces.

Here, when the fitting length between the cap member 84 and the cylindrical body 85 is adjusted, the position of the bellows 70 is changed. By changing the position of the bellows 70, the bellows 7
From 0, the starting point of the urging force on the valve body 64 is changed.
That is, as the fitting length between the cap member 84 and the cylindrical body 85 becomes longer, the bellows 70 and the valve body 68 become relatively closer to each other, and the bellows 7 in a state where the pressure in the pressure sensing chamber 68 is higher.
The urging force of 0 acts on the valve body 64. On the other hand, as the fitting length becomes shorter, the bellows 70 and the valve body 68 become relatively farther away, so that the urging force of the bellows 70 acts on the valve body 64 in a state where the pressure in the pressure sensing chamber 68 is lower. become.

Then, as described above, the solenoid 62
A predetermined urging force is applied to the valve body 68 by the forcible opening spring 65, and the urging force from the bellows 70 is applied to the pressure-sensitive rod 7 while a predetermined pressure is supplied to the pressure-sensitive chamber 68.
The fitting length is adjusted so that transmission to the valve body 68 via the second connector 2 starts. Thereby, the bellows 70 is arranged at a predetermined initial setting position. Then, in this state, the cap member 84 and the cylinder 85 are deformed and caulked together using a jig, and the cap member 84 is fixed to the cylinder 85.

Next, the operation of the displacement control valve 49 of the clutchless variable displacement compressor configured as described above will be described. When the detected temperature obtained from the room temperature sensor 58a is equal to or higher than the temperature set by the room temperature setter 58 with the air conditioner operation switch 59 turned on, the control computer 57 commands the excitation of the solenoid unit 62. . Then, a predetermined current is supplied to the coil 82 via the drive circuit 60, and as shown in FIGS.
An attractive force corresponding to the input current value is generated between them. This suction force is transmitted to the valve body 64 via the solenoid rod 81 as a force in the direction in which the opening degree of the valve hole 66 decreases, against the urging force of the forcible opening spring 65.

On the other hand, when the solenoid 62 is in the excited state, the bellows 70
It is displaced in accordance with the fluctuation of the suction pressure Ps introduced into the pressure-sensitive chamber 68 via 0. Then, the bellows 70 has a suction pressure P
s, the displacement of the bellows 70 is
Is transmitted to the valve body 64 via Therefore, the capacity control valve 4
In 9, the opening degree of the valve hole 66 is determined by the balance between the urging force from the solenoid portion 62, the urging force from the bellows 70, and the urging force of the forcible opening spring 65.

When the cooling load is large, for example, the difference between the temperature detected by the room temperature sensor 58a and the temperature set by the room temperature setter 58 increases. Control computer 57
Controls the input current value 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 60 to increase the input current value as the detected temperature increases. Therefore, the attraction force between the fixed iron core 76 and the movable iron core 78 increases, and the urging force in the direction of decreasing the set value of the opening degree of the valve hole 66 by the valve body 64 increases. Then, the valve 64 is opened and closed at a lower suction pressure Ps. Therefore,
When the current value is increased, the capacity control valve 49
It operates to maintain a lower suction pressure Ps.

As the valve opening of the valve body 64 decreases, the amount of refrigerant gas flowing from the discharge chamber 38 into the crank chamber 15 via the air supply passage 48 decreases. On the other hand, the refrigerant gas in the crank chamber 15 flows out to the suction chamber 37 via the axial passage 46, the inside of the blocking body 28, the pressure release port 47, the housing hole 27, and the port 45. For this reason, the crank chamber 15
The internal pressure Pc decreases. When the cooling load is large, the pressure in the suction chamber 37 is also high, and the difference between the pressure Pc in the crank chamber 15 and the pressure in the cylinder bore 11a is small. 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 64 of the capacity control valve 49 completely closes the valve hole 66, 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.

Conversely, when the cooling load is small, the difference between the temperature detected by the room temperature sensor 58a and the temperature set by the room temperature setting unit 58 becomes small. The control computer 57 instructs the drive circuit 60 to lower the input current value as the detected temperature is lower. For this reason, the suction force between the fixed iron core 76 and the movable iron core 78 becomes weak,
The urging force in the direction to decrease the set value of the opening degree of the valve hole 66 by the valve body 64 decreases. And a higher suction pressure P
At s, the valve body 64 is opened and closed. Therefore, the capacity control valve 49 operates so as to maintain a higher suction pressure Ps by decreasing the current value.

As the valve opening of the valve body 64 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 suction chamber 37 is low, and the pressure Pc in the crank chamber 15 and the pressure in the cylinder bore 11 are low.
The difference from the pressure in a becomes large. 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 lower than the set temperature, the control computer 57 instructs the drive circuit 60 to demagnetize the solenoid 62. The set temperature reflects a situation in which frost is likely to occur in the evaporator 55. Then, the supply of the current to the coil 82 is stopped, and the solenoid 62 is demagnetized,
Attraction force between the fixed iron core 76 and the movable iron core 78 disappears.

For this reason, as shown in FIG.
Is a follower spring 79 that acts via the movable iron core 78 and the solenoid rod 81 by the urging force of the forcible release spring 65.
Is moved downward in the figure against the biasing force of Then, the valve body 64 shifts to the opening position where the valve hole 66 is opened to the maximum. Therefore, a large amount of the high-pressure refrigerant gas in the discharge chamber 38 is supplied into 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.

Further, based on the OFF signal of the air conditioner operation switch 59, the control computer 57 causes the solenoid unit 6 to operate.
2, the inclination of the swash plate 22 also shifts to the minimum inclination.

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 82 of the solenoid portion 62. That is, the opening and closing are performed at a low suction pressure Ps as the input current value increases, and the opening and closing operation is performed at a high suction pressure Ps as the input current value decreases. 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 displacement 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 shown in FIG. 4, 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 slightly larger than 0 °. This minimum inclination state is brought about when the blocking body 28 is arranged at the closed position where the communication between the suction passage 32 and the accommodation hole 27 is blocked. The blocking body 28 is switched and arranged in conjunction with the swash plate 22 between the closed position and the open position separated from the closed position.

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 inside of the blocking body 28, the pressure release port 47, the housing hole 27, and the port 45. The refrigerant gas in the suction chamber 37 is sucked into the cylinder bore 11a and discharged to the discharge chamber 38 again.

That is, in the minimum inclination state, the discharge chamber 38, the air supply passage 48, the crank chamber 15, the shaft passage 46, the inside of the blocker 28, the pressure release passage 47,
7, a circulation passage passing through the communication port 45, the suction chamber 37 serving as a suction area, 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 59 in the ON state and the swash plate 22 in the minimum tilt position, when the temperature in the passenger compartment rises and the cooling load increases, the room temperature sensor 58
The temperature detected by a exceeds the set temperature of the room temperature setter 58. The control computer 57 commands the excitation of the solenoid 62 based on the detected temperature change, and the excitation of the solenoid 62 closes the air supply passage 48.
Then, the pressure Pc of the crank chamber 15 is reduced by the axial passage 46,
The pressure is reduced based on the pressure released to the suction chamber 37 through the pressure release port 47, the housing hole 27, and the port 45 inside the blocker 28. 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 82 of the displacement control valve 49 also stops. Therefore, the solenoid 62 is demagnetized, the air supply passage 48 is opened, and the inclination angle of the swash plate 22 is minimized. If the operation stop state of the compressor continues, the pressure in the compressor becomes uniform, but the inclination angle of the swash plate 22 is maintained at a small inclination angle by the biasing force of the inclination reduction spring 26. Therefore, when the operation of the compressor is started by the start of the vehicle engine, the swash plate 22
Starts rotating from the minimum tilt state where the load torque is the smallest, and there is almost no shock when the compressor is started.

According to the first embodiment configured as described above, the following effects can be obtained. In the control valve for a variable displacement compressor of the first embodiment, the initial setting position of the bellows 70 adjusts the fitting length between the cylinder 85 and the cap member 84, and the cap member 84 is attached to the cylinder 85. It is determined by fixing it. Therefore, it is not necessary to form an adjusting means such as a screw portion in order to determine the initial setting position of the bellows 70. Therefore, the shapes of the cylindrical body 85 and the cap member 84 can be simplified, and the processing and assembly of the cylindrical body 85 and the cap member 84 can be easily performed. That is, the processing cost of each part and the capacity control valve 4
9, the assembly control cost of the capacity control valve 4 can be reduced.
9 can reduce the total manufacturing cost.

Furthermore, it is not necessary to provide a screw portion having a predetermined length and a jig mounting portion for tightening the screw member. Accordingly, the size of the adjusting means for determining the initial setting position of the bellows 70 does not increase, and the overall size of the displacement control valve 49 can be reduced.

Further, in the control valve for a variable displacement compressor according to the first embodiment, the cap member 84 is
Is fixed by swaging. Therefore, the cap member 84 can be securely fixed to the cylindrical body 85 with a simple configuration, and the initial setting position of the bellows 70 can be easily and reliably determined.

(Second Embodiment) Next, a second embodiment in which the present invention is embodied as a control valve for a variable displacement compressor of a different type from the first embodiment will be described with reference to FIGS. 6 will be described. Note that the same parts as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and description thereof will be omitted.

As shown in FIG. 5, the displacement control valve 91 as the control valve of the second embodiment does not have the solenoid portion 62, and the valve body 64 forcibly closes the valve hole 66 by an external signal. The mechanism to open and close is not adopted. The pressure-sensitive member is a diaphragm 92 and a holding spring 93 instead of the bellows 70.

As shown in FIG. 6, the displacement control valve 91 is employed in a variable displacement compressor having no mechanism for opening and closing the suction passage 32 therein. In this variable displacement compressor, a drive shaft 16 is connected to an external drive source such as a vehicle engine via a clutch (not shown). The drive shaft 16 is supported by the front housing 12 and the cylinder block 11 via a pair of radial bearings 30. The rear end of the drive shaft 16 is supported by the valve plate 14 via a thrust bearing 94 and a shaft support spring 94a. Further, on the drive shaft 16, a circlip 16a for defining a minimum inclination angle of the swash plate 22 is provided. Moreover, the axial passage 46 is formed inside the receiving hole 27 at the rear end side center of the cylinder block 11, a pressure release groove 95 cut into the rear end surface of the cylinder block 11, and a communication hole formed in the valve plate 14. It is connected to the suction chamber 37 via 96.
The communication hole 96 has a predetermined throttle amount.

Next, the capacity control valve 9 of the second embodiment
1 will be described. As shown in FIGS. 5 and 6, the capacity control valve 91 includes a valve body 6 inside the valve housing 97.
4 and a diaphragm 92 and a pressing spring 93 as a pressure-sensitive member for adjusting the opening of the valve body 64 with respect to the valve hole 66. The valve body 64 includes a forced closing spring 98.
Accordingly, the pressure is always urged in a direction to close the valve hole 66. The valve body 64 is operatively connected to the diaphragm 92 via a pressure-sensitive rod 72.

In the valve housing 97, a pressure-sensitive chamber 68 and a spring chamber 99 are defined via the diaphragm 92. The pressure sensing chamber 68 communicates with the suction chamber 37 via a pressure detection port 69 and a pressure detection passage 50.

The valve housing 97 of the displacement control valve 91 is composed of a main body 100 and a cap member 101, and the cap member 101 is fitted on the outer peripheral surface of a cylindrical body 102 forming a large-diameter end of the main body 100. . A spring chamber 99 is formed by the cylindrical body 102, the cap member 101, and the diaphragm 92. The cap member 101 in the spring chamber 98 and the spring receiver 92 on the diaphragm 92
The pressing spring 93 is interposed between the pressing spring 93 and the contact spring a.
The biasing force of the holding spring 93 causes the diaphragm 92 to move.
Are arranged at predetermined initial setting positions.

Here, the cap member 101 adjusts the initial bending length of the pressing spring 93 by adjusting the fitting length of the cap member 101 to the cylindrical body 102, and further adjusts the diaphragm 9.
2 has a role of determining an initial setting position. With the fitting length adjusted, the cap member 101
Are fixed to the cylinder 102 by pins 103.

That is, the pressure-sensitive chamber 68, the spring chamber 99,
Diaphragm 92, holding spring 93 and pressure-sensitive rod 72
Thus, a pressure-sensitive mechanism that transmits the fluctuation of the suction pressure Ps to the valve body 64 is configured.

Next, the displacement control valve 9 of the second embodiment
A method of assembling the pressure sensing mechanism of the first aspect will be described. First, with the pressing spring 93 interposed between the cap member 101 and the spring receiver 92a of the diaphragm 92, the cap member 101 is fitted to the outer peripheral surface of the cylindrical body 102 of the main body 100. When a predetermined pressure is supplied to the pressure-sensitive chamber 68 via the pressure detection port 69, the diaphragm 9 in the pressure-sensitive chamber 68
2 is displaced according to the pressure of the pressure-sensitive chamber 68. This displacement is transmitted to the valve body 64 via the pressure-sensitive rod 72.
That is, in this state, the diaphragm 9 is
2 and the biasing force of the forcible closing spring 98 act. Then, the opening of the valve hole 66 by the valve body 64 is adjusted according to the balance of these urging forces.

Here, the cap member 101 and the cylinder 102
When the fitting length of the diaphragm 92 is adjusted, the initial setting length of the pressing spring 93 is changed, and the position of the diaphragm 92 is changed in accordance with the change. By changing the position of the diaphragm 92, the point at which the urging force acts on the valve body 64 from the diaphragm 92 is changed. That is, the shorter the fitting length between the cap member 101 and the cylindrical body 102 becomes, the more the pressing spring 9 becomes.
3, the initial setting length is large, and the initial urging force of the pressing spring 93 against the diaphragm 92 is small. Therefore, when the diaphragm 92 is displaced in accordance with the pressure in the pressure-sensitive chamber 28, the elasticity of the diaphragm 92 itself is the main opposing force. Therefore, the urging force of the diaphragm 92 acts on the valve body 64 while the pressure in the pressure-sensitive chamber 68 is higher.

On the other hand, as the fitting length becomes longer, the initial setting length of the pressing spring 93 becomes smaller,
, The initial urging force of the pressing spring 93 becomes large. Therefore, when the diaphragm 92 is displaced according to the pressure in the pressure sensing chamber 28, the initial biasing force of the pressing spring 93 becomes a large opposing force in addition to the elasticity of the diaphragm 92 itself. Therefore, the urging force of the diaphragm 92 acts on the valve body 64 in a state where the pressure in the pressure sensing chamber 68 is lower.

The fitting length is adjusted so that the urging force from the diaphragm 92 starts to be transmitted to the valve body 68 via the pressure-sensitive rod 72 while a predetermined pressure is supplied to the pressure-sensitive chamber 68. I do. Thereby, the diaphragm 92 is arranged at a predetermined initial setting position. Then, in this state, the pins 103 are driven into the cap member 101 and the cylinder 102 to fix the cap member 101 to the cylinder 102.

Next, the displacement control valve 9 of the second embodiment
The capacity control operation of the variable capacity compressor adopting No. 1 will be described. The displacement control valve 91 changes the valve body 64 according to the suction pressure Ps acting on the diaphragm 92 via the detection pressure passage 50.
, The opening degree of the valve hole 66 is adjusted. This capacity control valve 6
4, the discharge chamber 38 is supplied through the air supply passage 48.
The amount of the refrigerant gas supplied to the crank 15 is changed. Then, the difference between the pressure Pc in the crank chamber 15 acting before and after the piston 35 and the pressure in the cylinder bore 11a is adjusted. Thereby, the inclination angle of the swash plate 22 is changed, the stroke of the piston 35 is changed, and the discharge capacity is adjusted.

When the temperature in the vehicle compartment is high and the cooling load is large, the suction pressure Ps in the suction chamber 37 is high, and the difference between the pressure Pc in the crank chamber 15 and the pressure in the cylinder bore 11a via the piston 35 is obtained. rare. For this reason,
The swash plate 22 is disposed at the maximum inclination state shown by the solid line in FIG. 6, the stroke of the piston 35 is increased, and the compressor is operated at the maximum displacement. At this time, the capacity control valve 9
A high suction pressure Ps is guided to the first pressure sensing chamber 68 via the pressure detection passage 50. In this state, the high suction pressure Ps acts on the diaphragm 92, so that the diaphragm 92 is displaced toward the spring chamber 99. Therefore, the valve body 64 is kept in a state where the valve hole 66 is closed by the urging force of the forcible closing spring 98. That is, the supply passage 48 is shut off, and the supply of the high-pressure compressed refrigerant gas from the discharge chamber 38 to the crank chamber 15 is stopped.

When the temperature in the passenger compartment decreases and the cooling load decreases, the suction pressure Ps in the suction chamber 37 decreases. This low suction pressure Ps is applied to the displacement control valve 91 via the pressure detection passage 50.
The diaphragm 92 is displaced toward the pressure-sensitive chamber 68 in accordance with the degree of decrease in the suction pressure Ps.
This displacement is transmitted to the valve body 64 via the pressure-sensitive rod 72, and the valve body 64 is moved in a direction to open the valve hole 66.
Then, the opening area of the supply passage 48 at the capacity control valve 91 is increased. As a result, high-pressure compressed refrigerant gas is supplied from the discharge chamber 38 to the crank chamber 15 through the air supply passage 48. Note that the flow rate of the refrigerant gas supplied to the crank chamber 15 is changed according to the opening degree of the valve hole 66. As a result, the pressure Pc in the crank chamber 15 increases,
The difference between the pressure Pc in the crank chamber 15 and the pressure in the cylinder bore 11a via each piston 35 increases. In accordance with this difference, the swash plate 22 is moved to the minimum tilt angle side, the stroke of the piston 35 is reduced, and the discharge capacity is reduced.

When the temperature in the passenger compartment further decreases and approaches a state where the cooling load hardly exists, the suction chamber 3
7, the suction pressure Ps in the pressure control valve 91 further decreases.
Is opened at the maximum opening. In this state,
A large amount of high-pressure refrigerant gas is supplied from the discharge chamber 38 to the crank chamber 15 through the air supply passage 48. For this reason, the difference between the pressure Pc in the crank chamber 15 and the pressure in the cylinder bore 11a through each piston 35 is further increased, and the swash plate 22 is disposed in the minimum inclination state indicated by the chain line in FIG.
Then, the stroke of the piston 35 is further reduced, and the compressor is operated at the minimum displacement.

On the other hand, when the operation of the compressor is continued in a certain discharge capacity state and the temperature in the vehicle compartment increases and the cooling load increases, the suction pressure Ps in the suction chamber 37 increases. When the increased suction pressure Ps is led to the pressure sensing chamber 68 of the capacity control valve 91 via the pressure detection passage 50, the diaphragm 92 is displaced toward the spring chamber 99 in accordance with the degree of increase of the suction pressure Ps. This displacement is transmitted to the valve body 64 via the pressure-sensitive rod 72, and the valve body 64 is moved in a direction to close the valve hole 66. Then, the opening area of the supply passage 48 at the capacity control valve 91 is reduced. Thus, the flow rate of the high-pressure compressed refrigerant gas supplied from the discharge chamber 38 to the crank chamber 15 through the air supply passage 48 is reduced. On the other hand, the refrigerant gas in the crank chamber 15 flows through the axial passage 46 and the accommodation hole 2.
7, and is discharged into the suction chamber 37 through the pressure release groove 95 and the communication hole 96. As a result, the pressure Pc of the crank chamber 15
And the difference between the pressure Pc in the crank chamber 15 and the pressure in the cylinder bore 11a via the piston 35 decreases. In accordance with this difference, the swash plate 22 is moved to the maximum tilt angle side, the stroke of the piston 35 is increased, and the discharge capacity is increased.

When the temperature in the passenger compartment further increases and the cooling load further increases, the suction pressure Ps in the suction chamber 38 further increases, and the valve body 64 closes the valve hole 66. In this state, the air supply passage 48 is shut off, and the supply of the high-pressure compressed refrigerant gas from the discharge chamber 38 to the crank chamber 15 is stopped. Then, the refrigerant gas in the crank chamber 15 is discharged into the suction chamber 37 exclusively through the shaft passage 46, the inside of the housing hole 27, the pressure release groove 95 and the communication hole 96, and the pressure Pc in the crank chamber 15 is reduced. It decreases so as to approach the suction pressure Ps in the suction chamber 37. For this reason, the difference between the pressure Pc in the crank chamber 15 and the pressure in the cylinder bore 11a via the piston 35 is reduced, and the swash plate 22 is arranged at the maximum inclination. Then, the stroke of the piston 35 is increased, and the compressor is operated at the maximum discharge capacity.

That is, the variable displacement compressor having the above configuration
In a normal state, the discharge capacity is changed by raising and lowering the pressure Pc in the crank chamber 15 by adjusting the opening of the capacity control valve 91 in accordance with the cooling load, that is, the fluctuation of the suction pressure Ps,
Eventually, it plays a role in making the suction pressure Ps almost constant.

According to the second embodiment configured as described above, substantially the same effects as in the first embodiment can be obtained, and the configuration of the capacity control valve 91 can be simplified.

(Third Embodiment) Next, a third embodiment in which the present invention is embodied in a displacement control valve for a variable displacement compressor of a different type from the above embodiments will be described with reference to FIGS. 7 and 8. It will be described based on. In addition, parts that are the same as those in the first embodiment are assigned the same reference numerals as in the first embodiment, and descriptions thereof are omitted.

As shown in FIG. 7, a displacement control valve 111 as a control valve according to the third embodiment does not include a solenoid portion 62 as in the second embodiment, and a valve body is provided by an external signal. The mechanism for forcibly opening and closing the valve hole 66 is not adopted. Further, the pressure-sensitive rod 72 is fitted to the connecting portion 70a of the bellows 70 so as to be integrally movable.
Then, as shown in FIG.
It is disposed in the middle of a bleed passage 112 as a passage communicating the control pressure chamber of the variable displacement compressor having no mechanism for opening and closing the suction passage 32 therein and the suction region.

The bleed passage 112 is formed in the axial passage 46, the inside of the accommodation hole 27 at the rear end side center of the cylinder block 11,
Then, a bleed passage 112 formed of a communication passage 113 formed in the valve plate 14 and the rear housing 13 is formed. The capacity control valve 111 is provided in the middle of the communication passage 113. The discharge chamber 38 and the crank chamber 15 are always in communication with each other through an air supply passage 114 having a throttle portion 114a in the middle.

As shown in FIGS. 7 and 8, the capacity control valve 1
Inside the eleventh valve housing 115, a valve chamber 63 accommodating a valve body 64 and a pressure-sensitive chamber 68 accommodating a bellows 70 as a pressure-sensitive member are formed. The valve body 64 is operatively connected to the bellows 70 via a pressure-sensitive rod 72. The valve hole 65 communicates with the suction chamber 37 via the port 64 and the downstream communication passage 113. On the other hand, the valve chamber 63 is provided with the valve chamber port 67 and the communication passage 11 on the upstream side.
3. It communicates with the crank chamber 15 through the inside of the accommodation hole 27 and the axial passage 46. The pressure sensing chamber 68 communicates with the suction chamber 37 via a pressure detection port 69 and a pressure detection passage 50.

Now, the displacement control valve 111 is connected to the first
Similarly to the displacement control valve 49 of the embodiment, the valve housing 115 is constituted by a main body 116 and a cap member 84. One end of the main body 116 has a cylindrical tubular body 85.
The cap member 84 is provided on the outer peripheral surface of the cylindrical body 85.
Are fitted. Here, the cap member 84 and the cylinder 8
The cap member 84 is fixed to the cylindrical body 85 by caulking in a state where the initial setting position of the bellows 70 is determined by adjusting the fitting length with the bellows 5. The main body 116 and the cap member 84 form the pressure-sensitive chamber 68.
Are formed.

The method of assembling the pressure-sensitive mechanism of the displacement control valve 111 according to the third embodiment is as follows. First, the cap member 84 is put on the bellows 70 and the cap member is closed so that the valve body 64 closes the valve hole 66. 84 is fitted to the outer peripheral surface of the cylindrical body 85. In this state, a predetermined pressure is supplied to the pressure sensing chamber 68 through the pressure detection port 69, and the valve body 64
The fitting length between the cap member 84 and the cylindrical body 85 is adjusted so as to start opening. Thereby, the bellows 70 is arranged at a predetermined initial setting position. Then, in this state, the cap member 84 and the cylinder 85 are deformed and caulked together using a jig, and the cap member 84 is fixed to the cylinder 85.

Next, the displacement control valve 1 of the third embodiment
The displacement control operation of the variable displacement compressor employing the eleventh embodiment will be described. In this variable displacement compressor, the air supply passage 11
A predetermined amount of a high-pressure compressed refrigerant gas is continuously supplied from the discharge chamber 38 to the crank chamber 15 via the compressor 4. On the other hand, in the capacity control valve 111, the opening degree of the valve hole 66 by the valve body 64 is adjusted according to the suction pressure Ps acting on the bellows 70 via the detection pressure passage 50. This capacity control valve 11
By the opening degree adjustment of 1, the amount of the refrigerant gas extracted from the crank chamber 15 to the suction chamber 37 via the bleed passage 112 is changed. That is, the pressure Pc in the crank chamber 15 is changed, and the difference between the pressure Pc in the crank chamber 15 acting before and after the piston 35 and the pressure in the cylinder bore 11a is adjusted. Thereby, the inclination angle of the swash plate 22 is changed,
The stroke of the piston 35 is changed, and the discharge capacity is adjusted.

When the temperature in the passenger compartment is high and the cooling load is high, the suction pressure Ps in the suction chamber 37 is high, and the suction pressure Ps in the pressure sensing chamber 68 of the capacity control valve 111 is high via the pressure detection passage 50. Ps is derived. In this state, the bellows 70 is displaced in the contracting direction due to the high suction pressure Ps, and the valve body 64 remains in the state where the valve hole 66 is opened. That is, the bleed passage 112 is opened, the refrigerant gas in the crank chamber 15 is exclusively extracted into the suction chamber 37, and the rise in the pressure Pc in the crank chamber 15 is suppressed. Therefore, there is almost no difference between the pressure Pc in the crank chamber 15 and the pressure in the cylinder bore 11a via the piston 35. As a result, the swash plate 22 is arranged at the maximum inclination state shown by the solid line in FIG. 8, the stroke of the piston 35 is increased, and the compressor is operated at the maximum displacement.

When the temperature in the passenger compartment decreases and the cooling load decreases, the suction pressure Ps in the suction chamber 37 decreases. This low suction pressure Ps is applied to the capacity control valve 11 via the pressure detection passage 50.
When the bellows 70 is guided to the first pressure sensing chamber 68, the bellows 70 is displaced in a direction in which the bellows 70 extends in accordance with the degree of decrease in the suction pressure Ps. This displacement is transmitted to the valve body 64 via the pressure-sensitive rod 72, and the valve body 64 is moved in a direction to close the valve hole 66. Then, the opening area of the bleed passage 112 at the capacity control valve 111 is reduced. As a result, the amount of refrigerant gas extracted from the crank chamber 15 to the suction chamber 37 is reduced. On the other hand, a predetermined amount of high-pressure compressed refrigerant gas is constantly supplied from the discharge chamber 38 to the crank chamber 15 via the air supply passage 114. As a result, the pressure Pc in the crank chamber 15 gradually increases, and the difference between the pressure Pc in the crank chamber 15 and the pressure in the cylinder bore 11a via the piston 35 increases. In accordance with this difference, the swash plate 22 is moved to the minimum tilt angle side, the stroke of the piston 35 is reduced, and the discharge capacity is reduced.

When the temperature in the passenger compartment further decreases and approaches a state where the cooling load hardly exists, the suction chamber 3
The suction pressure Ps in 7 further decreases, and the bellows 70 is further extended. The displacement of the bellows 70 corresponds to the valve body 64.
And the valve body 64 completely closes the valve hole 66. In this state, the pressure Pc in the crank chamber 15 is further increased, and the difference between the pressure Pc in the crank chamber 15 and the pressure in the cylinder bore 11a via the piston 35 further increases. Then, the swash plate 22 is arranged in a minimum inclination state shown by a chain line in FIG. As a result, the stroke of the piston 35 is further reduced, and the compressor is operated at the minimum displacement.

On the other hand, when the operation of the compressor is continued in a certain discharge capacity state, and the temperature in the vehicle compartment increases and the cooling load increases, the suction pressure Ps in the suction chamber 37 increases. When the increased suction pressure Ps is guided to the pressure sensing chamber 68 of the capacity control valve 111 via the pressure detection passage 50, the bellows 70 is displaced in a direction in which the bellows 70 contracts in accordance with the degree of increase in the suction pressure Ps. This displacement is transmitted to the valve body 64 via the pressure-sensitive rod 72, and the valve body 64 is moved in a direction to open the valve hole 66.
Then, the opening area of the bleed passage 112 at the capacity control valve 111 is increased. Thereby, the crankcase 1
5, the amount of refrigerant gas extracted into the suction chamber 37 through the bleed passage 112 is increased. As a result, the crank chamber 15
, The difference between the pressure Pc in the crank chamber 15 and the pressure in the cylinder bore 11a via the piston 35 decreases. In accordance with this difference, the swash plate 22 is moved to the maximum tilt angle side, the stroke of the piston 35 is increased,
The discharge capacity is increased.

When the temperature in the passenger compartment further increases and the cooling load further increases, the suction pressure Ps in the suction chamber 38 further increases, and the bellows 70 is displaced in a direction to be further contracted. Is displaced in a direction to increase the opening of the valve hole 66. In this state, the bleed passage 11
2 is largely opened, and the refrigerant gas in the crank chamber 15 is exclusively extracted into the suction chamber 37. Therefore, the pressure Pc in the crank chamber 15 decreases so as to approach the suction pressure Ps in the suction chamber 37. As a result, the difference between the pressure Pc in the crank chamber 15 and the pressure in the cylinder bore 11a via the piston 35 is reduced, and the swash plate 22 is arranged at the maximum inclination. Then, the stroke of the piston 35 is increased, and the compressor is operated at the maximum discharge capacity.

The third embodiment configured as described above can provide substantially the same effects as the above embodiments. (Modification) The embodiment is not limited to the above, but may be modified as follows.

The capacity control valve 49 of the first embodiment
Is applied to the control valve of a variable displacement compressor with a clutch. With this configuration, for example, if the air conditioner operation switch 59 is in the off state, the clutch is disengaged, and if the air conditioner operation switch 59 is on, the same operation as the clutchless variable displacement compressor is performed. The number of times the clutch is engaged and disengaged can be drastically reduced, and the running feeling can be improved.

The capacity control valves 49, 9 of the above embodiments.
At 1, 111, the pressure sensing chamber 68 is connected to the crank chamber 15 via the pressure detection port 69 and the pressure detection passage 50 so that the pressure Pc of the crank chamber 15 is maintained substantially constant.

In the capacity control valves 49 and 91 of the first and second embodiments, the discharge chamber 38 is connected to the port 74 and the control pressure chamber is connected to the valve chamber port 67 via the air supply passage 48. To do.

The capacity control valve 91 of the second embodiment
In the above, the bellows 70 as described in the first embodiment is employed instead of the diaphragm 92 and the holding spring 93.

In the capacity control valves 49 and 91 of the first and second embodiments, the discharge chamber 38 is connected to the port 74 via the air supply passage 48 on the upstream side, and the discharge pressure is set in the valve hole 66. While introducing Pd, the crank chamber 15 is connected to the valve chamber port 67 via the downstream air supply passage 48,
Introducing the crank chamber pressure Pc into the valve chamber 63.

The displacement control valve 11 of the third embodiment
1, the crank chamber 15 is connected to the port 74 via the bleed passage 112 on the upstream side, and the valve chamber port 6
7 is connected to the suction chamber 37 via a bleed passage 112 on the downstream side.

The capacity control valves 49 and 9 of the above embodiments.
1, 111 are provided with a control pressure chamber independent of the crank chamber 15, and by changing the pressure of the control pressure chamber, the swash plate 2 is provided.
The control valve of the variable displacement compressor changes the difference between the pressure Pc in the crank chamber 15 accommodating the pressure chamber 2 and the pressure in the cylinder bore 11a through the piston 35, and changes the inclination angle of the swash plate 22 according to the difference. Apply. In this case, the air supply passage 4
8 or the bleed passage 112 has one end opened to the control pressure chamber.

The capacity control valves 49 and 9 of the above embodiments.
1, 111, the open ends of the cap members 84, 101 are connected to the main body 83 of the valve housings 61, 97, 115,
The cap members 84 and 101 are inserted into the cylindrical bodies 85 and 102 by inserting the cap members 84 and 101 into the inner peripheral surfaces of the cylindrical bodies 100 and 116.

Even with such a configuration, substantially the same effects as in the above embodiments can be obtained. In the capacity control valves 49, 91, 111 of the above embodiments, the cap members 84, 101 and the cylinders 85, 102 of the main bodies 83, 100, 116 of the valve housings 61, 97, 115 are press-fitted. In this case, of the cap members 84 and 101 and the cylindrical members 85 and 102, the outer diameter of the member on the inner peripheral side is formed to be slightly larger than the inner diameter of the member on the outer peripheral side. Then, at least one of the cooling of the member on the inner peripheral side and the heating of the member on the outer peripheral side is performed to fit the two members together.

In this case, the cap member 8
4 and 101 and the cylinders 85 and 102 can be brought into close contact with each other at the fitting portions thereof, and the possibility of rattling of the cap members 84 and 101 can be suppressed.

In the displacement control valves 49 and 111 of the first and third embodiments, the cap member 84 is connected to the cylindrical body 85 of the main bodies 83 and 116 of the valve housings 61 and 115.
In contrast, fix by spot welding instead of caulking with the fitting length adjusted.

The capacity control valve 91 of the second embodiment
, The cap member 101 is
Is fixed to the cylindrical body 102 of the main body 100 by spot welding in place of the pin 70 with its fitting length adjusted.

With such a configuration, the cap members 84, 101 and the main bodies 83, 100, 116 can be fixed with almost no deformation. Therefore,
With this deformation, it is possible to prevent the bellows 70, the presser spring 93, and the pressure-sensitive rod 72 from being disturbed from moving.

The technical ideas described below can be extracted from the embodiments and the modifications. (1) The control valve for a variable displacement compressor according to claim 1 or 2, wherein the cap member is press-fitted to the cylindrical body.

With this configuration, the cap member and the cylindrical body can be brought into close contact with each other at the fitting portion thereof,
It is possible to suppress the possibility of rattling of the cap member.

(2) The control valve for a variable displacement compressor according to any one of (1), (2) and (1), wherein the cap member is fixed to the cylinder by caulking. (3) The control valve for a variable displacement compressor according to any one of Claims 1, 2, and (1), wherein the cap member and the cylindrical body are fixed using pins.

With such a configuration, the fixing structure between the cap member and the cylinder can be simplified, and the manufacturing cost of the control valve can be reduced. (4) The control valve for a variable displacement compressor according to any one of Claims 1, 2, and (1), wherein the cap member is fixed to the cylindrical body by spot welding.

With this configuration, the cap member and the cylindrical body can be fixed with almost no deformation. Therefore, it is possible to suppress the possibility that the movement of the pressure-sensitive member such as the bellows and the pressure-sensitive rod that transmits the displacement of the pressure-sensitive member to the valve body may be hindered.

[0114]

As described in detail above, the present invention has the following excellent effects. That is, the shapes of the cylindrical body and the cap member can be simplified, and the initial setting position of the pressure-sensitive member can be easily determined. Therefore, as compared with the conventional configuration in which the initial setting position of the pressure-sensitive member is determined by the pair of screw members, the entire length of the pressure-sensitive mechanism does not increase, and the entire control valve does not increase in size. In addition, the initial setting position of the pressure-sensitive member can be determined with a simple configuration, and the manufacturing cost of the control valve can be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a control valve for a variable displacement compressor according to a first embodiment.

FIG. 2 is a sectional view showing a state in which the control valve of FIG. 1 is mounted on a clutchless variable displacement compressor.

FIG. 3 is an enlarged sectional view of a main part showing a state where the swash plate in FIG. 2 is at a maximum tilt position.

FIG. 4 is an enlarged sectional view of a main part showing a state where the swash plate in FIG. 2 is at a minimum tilt position.

FIG. 5 is a sectional view showing a control valve for a variable displacement compressor according to a second embodiment.

FIG. 6 is a sectional view showing a state where the control valve of FIG. 5 is mounted on a variable displacement compressor.

FIG. 7 is a sectional view showing a control valve for a variable displacement compressor according to a third embodiment.

8 is a sectional view showing a state where the control valve of FIG. 7 is mounted on a variable displacement compressor.

[Explanation of symbols]

15, a crank chamber also serving as a control pressure chamber; 32, a suction passage forming a suction pressure area; 37, a suction chamber forming a suction area; 38, a discharge chamber forming a discharge area; 48, a discharge area and a control pressure chamber; An air supply passage as a passage for communicating
91, 111: capacity control valve as control valve, 50: detection pressure passage, 62: solenoid part, 63: valve chamber, 64: valve body,
66 ... a valve hole, 68 ... a pressure-sensitive chamber constituting a part of a pressure-sensitive mechanism,
70: a bellows constituting a part of the pressure sensing mechanism and a pressure sensing member; 71: a pressure sensing rod guide constituting a part of the pressure sensing mechanism; 72 ... a pressure sensing rod constituting a part of the pressure sensing mechanism; 81: solenoid rod, 82: coil, 84, 1
01: cap member, 85: cylindrical body, 92: diaphragm constituting a part of the pressure-sensitive mechanism and as a pressure-sensitive member,
93: a presser spring that constitutes a part of the pressure-sensitive mechanism and also serves as a pressure-sensitive member; 99: a spring chamber that constitutes a part of the pressure-sensitive mechanism; 112: air extraction as a passage communicating the suction area with the control pressure chamber aisle.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Takeshi Takeshi 2-1-1 Toyota-cho, Kariya-shi, Aichi Prefecture Inside Toyota Industries Corporation (72) Inventor Takuya Okuno 2-1-1 Toyota-cho, Kariya-shi, Aichi Prefecture Inside Toyota Industries Corporation (72) Inventor Eiji Tokunaga 2-1-1 Toyota-machi, Kariya City, Aichi Prefecture Inside Toyota Industries Corporation

Claims (4)

[Claims] 1. A control valve of a variable displacement compressor which changes a discharge capacity by opening and closing a passage communicating a suction region or a discharge region with a control pressure chamber, wherein the control valve is connected to the passage through a valve hole. A valve chamber accommodated in the valve chamber for opening and closing the valve hole; a pressure-sensitive mechanism connected to the suction area or the control pressure chamber via a pressure detection passage; And a pressure-sensitive member that is configured to be displaced in accordance with the pressure of the suction area or the control pressure chamber, and that is connected to the valve body via a pressure-sensitive rod. A control for a variable displacement compressor in which a part is constituted by a cylinder and a cap member, and the cap member is fitted to the cylinder and fixed at a predetermined position to determine an initial setting position of the pressure-sensitive member. valve. 2. A control valve for a variable displacement compressor, which opens and closes a passage connecting a suction region or a discharge region and a control pressure chamber to change a discharge capacity, wherein the control valve is connected to the passage through a valve hole. A valve chamber accommodated in the valve chamber for opening and closing the valve hole, a solenoid connected to the valve body via a solenoid rod, and a pressure detection passage in the suction area or the control pressure chamber. A pressure-sensitive mechanism connected via a pressure-sensitive mechanism, the pressure-sensitive mechanism being housed in the pressure-sensitive mechanism, configured to be displaced in accordance with the pressure in the suction area or the control pressure chamber, and connected to the valve body via a pressure-sensitive rod. A part of a peripheral wall of the pressure-sensitive mechanism is constituted by a cylinder and a cap member, and the cap member is fitted to the cylinder and fixed at a predetermined position, and the pressure-sensitive member is fixed. Variable capacity to determine the initial setting position of Control valve for compressor. 3. A control valve for a variable displacement compressor which changes a discharge capacity by opening and closing a passage communicating between a suction area or a discharge area and a control pressure chamber, wherein the control valve includes a valve hole. A valve chamber housed in the valve chamber for opening and closing the valve hole, a pressure-sensitive mechanism connected to the suction area or the control pressure chamber via a pressure detection passage, and a pressure-sensitive mechanism connected to the valve chamber. A pressure-sensitive member housed in a mechanism, configured to be displaced in accordance with the pressure of the suction area or the control pressure chamber, and having a pressure-sensitive member connected to the valve body via a pressure-sensitive rod. In the method for assembling a control valve, a part of the peripheral wall of the pressure-sensitive mechanism is constituted by a cylinder and a cap member, and the cap member is fitted to the cylinder and a predetermined pressure is set in a pressure-sensitive chamber in the pressure-sensitive mechanism. In a state where pressure is applied, the pressure-sensitive member is arranged at a predetermined initial setting position. After adjusting the fitting length between the cylinder and the cap member, the method of assembling the control valve to secure said cap member relative to the tubular body. 4. A control valve for a variable displacement compressor which changes a discharge capacity by opening and closing a passage connecting a suction area or a discharge area to a control pressure chamber, wherein the control valve includes a valve hole. A valve chamber housed in the valve chamber and opening and closing the valve hole, a solenoid connected to the valve body via a solenoid rod, and a valve in the suction area or the control pressure chamber. A pressure-sensitive mechanism connected via a pressure passage, housed in the pressure-sensitive mechanism, configured to be displaced in accordance with the pressure in the suction area or the control pressure chamber, and to the valve body via a pressure-sensitive rod. A pressure-sensitive member connected to the variable displacement compressor control valve, wherein a part of the peripheral wall of the pressure-sensitive mechanism is constituted by a cylinder and a cap member, and the cap member is attached to the cylinder. Mating to supply a predetermined current to the coil of the solenoid section. While the predetermined pressure is being applied to the pressure-sensitive chamber in the pressure-sensitive mechanism, the fitting length between the cylinder and the cap member is set so that the pressure-sensitive member is disposed at a predetermined initial setting position. A method of assembling a control valve for a variable displacement compressor, which fixes the cap member to the cylinder after adjusting the length.