JP2000220576A - Control valve for variable displacement compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the structure of a control valve in carrying out the OFF- side control and the ON-side control of the compressor of a variable displacement swash plate type by one control valve. SOLUTION: Inside the valve housing 51 of a control valve 51, an opening/ closing valve mechanism 60 for controlling the opening/closing of an air supply passage 28 for communicating a discharge chamber 22 with a crank chamber 5, and an adjust valve mechanism 70 for optionally adjusting the opening degree of an air extracting passage 27 for communicating a suction chamber 21 with the crank chamber 5 are incorporated to operate independently of each other. One coil 85 is shared b the first plunger 82 of the opening/closing valve mechanism and the second plunger 83 of the adjust valve mechanism. An adjust valve body 73 and a pressure sensitive member (bellows) 76 constituting the adjust valve mechanism are arranged in the same chamber 71, to which suction pressure Ps is applied.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control valve used in a variable displacement compressor capable of changing a tilt angle of a swash plate based on control of an internal pressure of a crank chamber to adjust a discharge capacity.

[0002]

2. Description of the Related Art Generally, the displacement of a variable displacement swash plate type compressor is adjusted by changing the swash plate angle based on the internal pressure control of a crank chamber. One of the control methods of the pressure in the crank chamber is a pull-out control. This is a control method in which the crank pressure (Pc) is adjusted by controlling the amount of gas released from the crank chamber on the assumption that a constant amount of high-pressure refrigerant gas equivalent to the discharge pressure is always supplied to the crank chamber. It is difficult to increase the crank pressure quickly by such pure control on the removal side, which has been one of the causes of poor variable control of the discharge capacity (that is, response delay). In order to overcome such drawbacks of pure pull-out control, a control valve having both a pull-side control valve mechanism and an inlet-side control valve mechanism has been conventionally proposed. For example, Japanese Patent Application Laid-Open No. 5-99136 discloses a control valve. Kaihei 10-10324
No. 9 has a control valve disclosed therein.

[0003] The control valve disclosed in Japanese Patent Application Laid-Open No. 5-99136 discloses a first valve element 232 that controls opening and closing of a first communication passage that connects a discharge chamber and a crank chamber of a compressor, a crank chamber and a suction chamber. Valve body 2 that controls the opening and closing of a second communication passage that communicates
35, and a common transmission rod that is electromagnetically driven to operate both the valve bodies. The operation areas of the first and second valve bodies are completely separated according to the amount of movement of the transmission rod, so that both valves are simultaneously operated. Use a configuration that does not open the valve. However, the control valve disclosed in Japanese Patent Application Laid-Open No. 5-99136 discloses a substantially annular second valve.
Since the transmission rod is inserted into the valve body 235 so as to be relatively slidable, even after the second valve body 235 is seated on the valve seat portion 231b, the sealing property of the sliding contact portion between the valve body and the transmission rod is maintained. However, there is a disadvantage that gas leakage from the crank chamber to the suction chamber is inevitable.

On the other hand, a control valve disclosed in Japanese Patent Application Laid-Open No. 10-103249 includes an on-off valve body 90 for opening and closing an air supply passage connecting a discharge pressure region and a crank chamber, and an on-off rod 91 integrated therewith. An opening / closing rod 91 comprising an adjusting valve body 102 for adjusting the opening of a bleed passage connecting the crank chamber and the suction pressure region, and an adjusting rod 100 integrated therewith;
The two rods 90 and 102 can be operated independently by inserting an adjusting rod 100 therein so as to be relatively movable, and plungers are provided at lower ends of both rods, and each plunger can be electromagnetically biased by a common coil. And According to the control valve disclosed in Japanese Patent Application Laid-Open No. Hei 10 (1998), there is no problem of gas leakage from between the valve element and the rod as in the control valve described in Japanese Patent Application Laid-Open No. Hei 5 (1995) as long as each valve element is seated on the corresponding valve seat. .

However, Japanese Patent Laid-Open No. 10-103249 merely proposes a control valve configuration for a special clutchless type variable displacement swash plate type compressor. That is, the compressor is provided with a blocking member 38 capable of blocking the communication between the suction passage 42 and the suction chamber 47 in the inner end region of the drive shaft, and based on the blocking operation by the blocking member 38, an external refrigerant circuit is provided. This is to stop the flow of the refrigerant. When the communication between the suction passage 42 and the suction chamber 47 is blocked by the blocking body 38,
Two suction pressure regions (ie, 42 and 47) appear. Therefore, also in the control valve incorporated in the compressor, the pressure sensing chamber 96 for sampling the primary suction pressure Pse of the suction passage 42 on the upstream side and the suction chamber 47 on the downstream side are sampled.
And a regulating valve chamber 95 communicating with the (secondary suction pressure Psc) is provided separately, and both chambers 95 and 96 are separated from each other by a partition.
Care is taken to prevent the suction passage 42 and the suction chamber 47 from directly communicating with each other via the inside of the control valve. For this reason, the two rooms 9
It is necessary to exercise caution in the management of the rod clearance of the pressure-sensitive rod 106 that must be provided through the partition wall between 5,96.

The object of the present invention is applicable to a general variable displacement compressor having no blocker,
An object of the present invention is to provide a control valve of a variable displacement compressor having both a pull-out control valve mechanism and an inlet-side control valve mechanism, which has a simpler structure, is easier to manufacture, and is more cost effective than conventional control valves.

[0007]

The gist of the present invention is that of claim 1
As described in 2, 3, 4 and 5, respectively. According to the control valve of the first aspect, the opening / closing valve mechanism and the regulating valve mechanism are independently operably incorporated in the valve housing, so that both mechanisms can simply maintain the respective functions within the same control valve. It is structured. Therefore, simplification and downsizing of the capacity control configuration of the compressor and reduction in manufacturing cost are achieved. Also, since one coil is provided for the first and second plungers and the on-off valve body and the adjustment valve body are simultaneously electromagnetically energized by energizing the coils, the coil is used as a valve of both valve mechanisms. It can be commonly used for body positioning control, and the structure is simplified. Further, at least two of the adjusting valve body and the pressure-sensitive member constituting the adjusting valve mechanism are disposed in the same chamber to which the suction pressure is applied. In other words, the adjustment valve element and the pressure-sensitive member are disposed in the same chamber that serves as both chambers without distinguishing between the valve chamber for the adjustment valve element and the pressure-sensitive chamber for the pressure-sensitive member. In this respect, the number of rooms is smaller than that of the control valve disclosed in JP-A-10-103249, and the number of movable rods that need to penetrate the partition wall is also reduced. Valves are more advantageous. However, the control valve of claim 1 is not suitable for a clutchless compressor having a shutoff.

According to the control valve of the second aspect, a rod for connecting the on-off valve body of the on-off valve mechanism to the first plunger and a rod for connecting the adjustment valve body of the adjustment valve mechanism to the second plunger. One of the two rods was formed in a cylindrical shape, and the other rod was fitted into one of the rods so as to be relatively movable. For this reason, each valve body of both valve mechanisms can be arranged close to one side of their plungers, and it is possible to suppress an increase in the size of a control valve having two valve mechanisms in the axial direction. Further, since the coil can be arranged at the end of the valve housing, when the control valve is installed in the housing of the compressor, the coil can be installed in a state where the coil portion is exposed outside the compressor housing. Wiring work becomes easier. Note that this configuration is also a specific configuration that allows the independent operation of each of the on-off valve body and the adjustment valve body.

According to the control valve of the third aspect, the adjusting valve body of the adjusting valve mechanism and the pressure-sensitive member are connected so as to be able to contact and separate from each other.
Even when the supply of current to the coil is stopped and the suction pressure is high, without being affected by the displacement operation of the pressure-sensitive member,
The adjusting valve body can be moved in a direction approaching the adjusting valve hole by the urging action of the closing spring.

According to the control valve of the fourth aspect, one end of the on-off valve hole of the on-off valve mechanism is communicated with the discharge pressure region at the other end, and the rod connecting the on-off valve body and the first plunger is cut off. Since the area (S1) is made substantially equal to the opening area (S2) of the on-off valve hole, the pressure receiving areas on both sides in the moving direction of the on-off valve element become almost equal, and the pressure acting on the valve element is almost completely reduced. Can be offset. Therefore, even when the pressure acting on the on-off valve body increases, the movement of the valve body becomes smooth (for details, refer to the embodiment of the invention).

[0011] Claim 5 clarifies that the control valve of the present invention is particularly suitable for a variable displacement compressor with a clutch.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is embodied in a displacement control valve incorporated in a variable displacement swash plate type compressor with a clutch will be described below with reference to FIGS.

(Outline of Compressor Body) As shown in FIG.
The swash plate compressor includes a cylinder block 1, a front housing 2 joined to a front end thereof, and a cylinder block 1;
And a rear housing 4 joined to the rear end via a valve body 3. These 1, 2, 3, and 4 are joined and fixed to each other by a plurality of through bolts (not shown), and constitute a compressor housing. A crank chamber 5 is defined in a region surrounded by the cylinder block 1 and the front housing 2. A drive shaft 6 is rotatably supported in the crank chamber 5 by a plurality of radial bearings mounted in the housing. A coil spring 7 and a rear thrust bearing 8 are provided in a central concave portion of the cylinder block 1. On the other hand, the drive shaft 6
A rotary support 11 is fixed thereon so as to be integrally rotatable, and a front thrust bearing 9 is disposed between the rotary support 11 and the inner surface of the front housing 2. Drive shaft 6
Is thrust supported by a rear bearing 8 and a front bearing 9 urged forward by a spring 7.

The front end of the drive shaft 6 is operatively connected to a vehicle engine E as an external drive source via an electromagnetic clutch 40. The electromagnetic clutch 40 is connected to the front housing 2
A pulley 42 rotatably supported by a bearing 41 on a front cylindrical portion of the drive shaft 6, an annular solenoid coil 43, and a front end region of the drive shaft 6 are slidably moved forward and backward while being urged by a leaf spring 44. Armature 45 provided.
FIG. 1 shows the armature 4 against the urging force of the leaf spring 44.
5 shows a state in which 5 is joined to the end face of the pulley 42. When the armature 45 is attracted and joined to the end face of the pulley 42 by electromagnetic force generated by energizing the coil 43, the driving force of the engine E is transmitted to the drive shaft 6 via the power transmission belt 46, the pulley 42 and the armature 45. You. If the electromagnetic force disappears due to the stoppage of the current supply to the coil 43, the armature 45 is separated from the pulley 42 by the urging force of the leaf spring 44, and the power transmission is cut off. As described above, the engine power is selectively transmitted to the drive shaft 6 based on the control of energizing the coil 43.

Further, a swash plate 12 serving as a cam plate is accommodated in the crank chamber 5. The swash plate 12 has a through hole formed in the center thereof, and the drive shaft 6 is inserted through the through hole. The swash plate 12 is operatively connected to the rotation support 11 and the drive shaft 6 via a hinge mechanism 13 as a connection guide mechanism. The hinge mechanism 13 includes a support arm 14 having a guide hole protruding from a rear surface of the rotary support 11 and a swash plate 1.
2 and a guide pin 15 with a spherical head protruding from the front surface of the second. Then, by the linkage between the support arm 14 and the guide pin 15 constituting the hinge mechanism 13 and the contact with the drive shaft 6 in the central insertion hole of the swash plate 12,
The swash plate 12 is rotatable in synchronization with the drive shaft 6 and is capable of tilting with respect to the drive shaft 6 while sliding the drive shaft 6 in the axial direction.

A coil-shaped inclination-reducing spring 16 is provided on the drive shaft 6 between the rotary support 11 and the swash plate 12. The spring 16 urges the swash plate 12 in a direction approaching the cylinder block 1 (that is, a direction in which the inclination angle decreases). A circlip 17 is fixed on the drive shaft 6 behind the swash plate 12, and the circlip 17 restricts the swash plate 12 from retreating further, thereby reducing the minimum inclination angle of the swash plate 12 (for example, 3 to 3).
5 °). On the other hand, the maximum inclination angle of the swash plate 12 is determined when the counterweight portion 12a of the swash plate 12 abuts on the regulating portion 11a of the rotary support 11.

As shown in FIG. 1, the cylinder block 1 has a plurality of cylinder bores 1a surrounding the drive shaft 6.
A single-headed piston 18 is reciprocally accommodated in each cylinder bore 1a.
The end of each piston 18 is moored to the outer periphery of the swash plate 12 via a pair of shoes 19, and the piston 18 and the swash plate 12 are operatively connected via the shoes 19.

Between the valve body 3 and the rear housing 4, a suction chamber 21 located in a central area and a discharge chamber 22 surrounding the suction chamber 21 are defined. The valve body 3 has a suction port 23 and a port 2 corresponding to each cylinder bore 1a.
3 is formed, and a discharge port 25 for opening and closing the discharge port 25 and a discharge valve 26 for opening and closing the port 25 are formed.
Through the suction port 23, the suction chamber 21 and each cylinder bore 1
a, and each cylinder bore 1 a is communicated with the discharge chamber 22 through the discharge port 25.

In the swash plate type compressor shown in FIG. 1, when the drive shaft 6 is rotated by the power supply from the engine E, the swash plate 12 inclined at a predetermined angle is rotated. Then, each piston 18 is reciprocated at a stroke corresponding to the inclination angle of the swash plate, and in each cylinder bore 1a, the suction chamber 21 (suction pressure P
s area), suction and compression of the refrigerant gas from the
The discharge of the compressed refrigerant gas to the (area of the discharge pressure Pd) is sequentially repeated.

The tilt angle of the swash plate 12 of this compressor is determined by the moment of the rotational motion based on the centrifugal force when the swash plate rotates, the moment by the spring force based on the biasing action of the tilt reducing spring 16, and the gas pressure. There are three moments.
The product of inertia of the swash plate 12 is set such that the moment of the rotational motion always acts in the direction of increasing the tilt angle. On the other hand, the moment due to the gas pressure is the mutual reaction between the compression reaction force acting on the piston of the cylinder bore in the compression stroke, the internal pressure of the cylinder bore in the suction stroke, and the internal pressure of the crank chamber 5 (crank pressure Pc) which corresponds to the piston back pressure. This is a moment generated based on the relationship, and acts in the direction of decreasing the tilt angle. In the present embodiment, by maintaining the crank pressure Pc at a high level, the sum of the moment due to the gas pressure and the moment due to the spring force of the inclination reducing spring 16 exceeds the moment in the inclination increasing direction due to the rotational motion, and the swash plate 12 Is designed to be set to the minimum inclination. Also, the crank pressure P
By adjusting c, the sum of the moment due to the gas pressure and the moment due to the spring force is balanced with the moment of the rotational motion, and the inclination angle of the swash plate 12 is set to an arbitrary angle between the minimum inclination angle and the maximum inclination angle. You can do it. Thus, the inclination of the swash plate 12 is determined based on the control of the crank pressure Pc, and the stroke of each piston 18, that is, the displacement of the compressor is variably adjusted according to the inclination.

As shown in FIGS. 1 and 2, the crank pressure P
The mechanism for controlling c is constituted by a capacity control valve 50 and various passages 27, 28 and 29. That is, the compressor housing is provided with a bleed passage 27 connecting the crank chamber 5 and the suction chamber 21 and an air supply passage 28 connecting the crank chamber 5 and the discharge chamber 22. Bleed passage 27
In the middle of the air supply passage 28, there is provided a control valve 50 capable of independently controlling the opening degree of communication between the two passages 27, 28. The bleed passage 27 and the supply passage 28 are common passages between the control valve 50 and the crank chamber 5.
The portion of the bleed passage 27 connecting the control valve 50 and the suction chamber 21 also functions as a pressure detection passage for guiding the suction pressure Ps to the control valve 50. Further, a communication passage 29 serving as an auxiliary air supply passage connecting the crank chamber 5 and the discharge chamber 22 is provided separately from the air supply passage 28 in the compressor housing. The communication passage 29 has a fixed throttle 29a in the middle thereof.

(External Refrigerant Circuit and Electronic Control of Compressor) The discharge chamber 22 and the suction chamber 21 of the compressor are connected via an external refrigerant circuit 30. The external refrigerant circuit 30 forms a cooling circuit of the vehicle air conditioner together with the compressor. The external refrigerant circuit 30 includes a condenser (condenser) 3
1. Temperature type expansion valve 32 and evaporator (evaporator) 3
3 are provided. The opening degree of the expansion valve 32 is determined by the evaporator 33.
Feedback control is performed based on the detected temperature and the evaporating pressure of the temperature-sensitive cylinder provided on the outlet side, and the expansion valve 32 supplies the liquid refrigerant corresponding to the heat load to the evaporator 33 to control the refrigerant flow rate in the external refrigerant circuit 30. Adjust.

Further, as shown in FIG. 2, a temperature sensor 34 is provided near the evaporator 33. The temperature sensor 34 detects the temperature of the evaporator 33 and provides the evaporator temperature information to the control computer C. The control computer C manages all controls related to cooling and heating of the vehicle air conditioner. A temperature sensor 3 is provided on the input side of the control computer C.
In addition to 4, a room temperature sensor 35 for detecting the vehicle indoor temperature, a room temperature setting device 36 for setting the vehicle indoor temperature, an air conditioner operation switch 37, and an engine speed sensor 38 are connected. On the other hand, on the output side of the control computer C, a drive circuit 39A for controlling the energization of the solenoid coil 43 of the electromagnetic clutch 40 and a drive circuit 39B for controlling the energization of the coil 85 of the control valve 50 described later are connected. Have been. The control computer C includes an evaporator temperature obtained from the temperature sensor 34 and a room temperature sensor 35.
, The desired room temperature set by the room temperature setting device 36, and the ON from the air conditioner operation switch 37
Based on the / OFF setting status and external information such as information on the engine speed from the engine speed sensor 38, the electromagnetic clutch 40 is controlled, and an appropriate energization amount to the coil 85 of the control valve 50 is calculated. Then, the current of the calculated current value is supplied from the drive circuit 39B to the control valve 50.
To externally control the opening degree of the control valve and the set suction pressure Pset.

(Structure of Capacity Control Valve) As shown in FIG.
The capacity control valve 50 includes an opening / closing valve mechanism 60 for controlling opening / closing of the air supply passage 28 connecting the discharge chamber 22 and the crank chamber 5;
An adjusting valve mechanism 70 for arbitrarily adjusting the opening (or the amount of throttle) of the bleed passage 27 connecting the crank chamber 5 and the suction chamber 21.
And a solenoid mechanism 80 operatively connected to the two valve mechanisms 60 and 70. These three mechanisms are controlled by the control valve 50.
Is incorporated in the valve housing 51 constituting the outer shell of the main body. Note that the opening / closing valve mechanism 60 and the adjustment valve mechanism 70 can be operated independently of each other as described later.

The opening / closing valve mechanism 60 includes a valve housing 51
An opening / closing valve chamber 61 and a communication chamber 62 are vertically partitioned adjacent to each other. The on-off valve chamber 61 communicates with the discharge chamber 22 via the air supply port 52 and the air supply passage 28, and the pressure of the discharge chamber 22 (discharge pressure Pd) is guided into the on-off valve chamber 61. The communication chamber 62 communicates with the crank chamber 5 through a communication port 53 and passages 27 and 28 common to the bleed air supply. A crank pressure Pc is guided into the communication chamber 62. An opening / closing valve hole 63 is formed below the communication chamber 62 (on the opening / closing valve chamber 61 side). The on-off valve chamber 61, the communication chamber 62, and the on-off valve hole 63 form a part of the air supply passage 28 in the control valve 50. An opening / closing valve body 64 is provided in the opening / closing valve chamber 61 so as to be movable in a vertical direction (axial direction of the control valve). The main body of the on-off valve body 64 opens and closes the on-off valve hole 63 with the movement. The lower end of the on-off valve body 64 is connected to an on-off plunger 82 as a first plunger via an on-off rod 65. Opening and closing plunger 82
Exists in a solenoid chamber 81 below the on-off valve chamber 61. The opening spring 66 is provided between the on-off valve body 64 and the valve housing 5.
1 is interposed. The opening spring 66 urges the opening / closing valve body 64 in a direction away from the opening / closing valve hole 63, and normally brings the opening / closing valve hole 63 into an open state. The opening / closing valve body 64, the opening / closing rod 65, and the opening / closing plunger 82 are integrated, and the integrated body has a cylindrical shape with an insertion hole 67 passing through the center. Further, the sectional area S1 of the opening / closing rod 65 connecting the opening / closing valve body 64 and the opening / closing plunger 82 is set to be substantially equal to the opening area S2 of the opening / closing valve hole 63.

The adjustment valve mechanism 70 includes a valve housing 51
And a regulating valve chamber 71 partitioned above the communication chamber 62. The regulating valve chamber 71 is also a pressure sensing chamber, and is communicated with the suction chamber 21 through the bleed / pressure sensing port 54 and the bleed / detection passage 27. (Suction pressure Ps). However, an annular spring seat 55 is provided in the adjustment valve chamber 71 from the inner peripheral wall of the valve housing 51 toward the axis.
The regulating valve chamber 71 is apparently divided into an upper region and a lower region by the spring seat portion 55. These two regions are clearly communicated with each other by the center hole of the spring seat portion, and the pressure is increased. Are equivalent to each other. An adjustment valve hole 72 that forms an annular valve seat is provided in a housing partition (upper side of the communication chamber 62) in a boundary area between the adjustment valve chamber 71 and the communication chamber 62. The communication chamber 62, the adjustment valve chamber 71, and the adjustment valve hole 72 form a part of the bleed passage 27 in the control valve 50.

An adjusting valve body 73 is disposed in the adjusting valve chamber 71 of the adjusting valve mechanism 70 so as to be movable in the vertical direction. The adjusting valve body 73 adjusts the opening degree of the adjusting valve hole 72 in accordance with the movement. I do. The lower end of the adjustment valve body 73 is provided via an adjustment rod 74.
It is connected to an adjustment plunger 83 as a second plunger. The adjustment plunger 83 exists in the solenoid chamber 81. The adjusting rod 74 is connected to the communication chamber 62 and the on-off valve chamber 61.
And extends over three of the solenoid chambers 81, and is inserted into the insertion hole 67 at the center of the opening / closing rod 65 so as to be relatively movable. The closing spring 75 includes the adjusting valve body 73 and the spring seat 5.
5 is interposed. The closing spring 75 urges the adjustment valve body 73 in a direction approaching the adjustment valve hole 72, and normally closes the adjustment valve hole 72. A bellows 76 as a pressure-sensitive member is further provided in the adjustment valve chamber (pressure-sensitive chamber) 71. A base end (upper end) of the bellows 76 is fixed to a ceiling wall of the valve chamber 71, and a connecting tube 7 is provided at a front end (lower end).
7 is fixed. The distal end of a pressure-sensitive rod 78 protruding from the adjusting valve body 73 is inserted into the connecting cylinder 77 so as to be relatively movable, and the bellows 76 is operatively connected to the adjusting valve body 73 so as to be able to come and go. ing. The bellows 76 expands and contracts autonomously in accordance with the magnitude of the suction pressure Ps guided into the adjustment valve chamber (pressure sensing chamber) 71, and the adjustment valve body 73 closes the adjustment valve hole 72 based on the expansion and contraction operation. Participates in opening control.

The solenoid mechanism 80 has a solenoid chamber 81 defined in the valve housing 51. On the other hand, when the control valve 50 is mounted on the compressor rear housing 4, an annular chamber 56 is formed between the outer peripheral surface of the valve housing 51 and the inner wall surface of the rear housing 4 at a position substantially corresponding to the communication chamber 62. You. Valve housing 5
1, a pressure conducting path 57 connecting the annular chamber 56 and the solenoid chamber 81 is formed, and the communication port 53 and the annular chamber 5 are formed.
The crank pressure Pc spreads to the solenoid chamber 81 via the pressure passage 6 and the pressure conducting path 57. Further, on one side (upper region) of the solenoid chamber 81, a fixed iron core 84 is provided. In the solenoid chamber 81, an opening / closing plunger 82 of the opening / closing valve mechanism 60 and an adjusting plunger 83 of the adjusting valve mechanism 70 are accommodated near the fixed iron core 84. One coil 85 is attached to the fixed iron core 84 so as to surround the plungers 82 and 83. The energization of the coil 85 is controlled by the control computer C. The plunger 8 is moved based on an electromagnetic biasing force generated by energizing the coil 85.
2 and 83 are moved upward (in the direction of approaching the fixed iron core 84) upward against the downward biasing force of the corresponding springs 66 and 75, respectively.

When the coil 85 is energized with the minimum current value, the upward electromagnetic biasing force of the opening / closing plunger 82 exceeds the downward biasing force of the opening spring 66, and the opening / closing valve mechanism 60 is fully closed. Conversely, if no current is supplied to the coil 85, the on-off valve mechanism 60 is fully opened. Therefore, the on-off valve mechanism 6
0 can be regarded as an input ON / OFF valve that can be controlled externally. On the other hand, the regulating valve mechanism 70 can be regarded as a variable internal pressure control valve of a set pressure variable type that can change the set suction pressure Pset in accordance with the amount of current supplied to the coil 85.

(Operation) The operation of the variable displacement compressor will be described. When the air conditioner operation switch 37 is turned off, the electromagnetic clutch 40 is in the cut-off state, there is no power supply from the engine E to the compressor, and the compressor stops operating. In this case, the coil 85 of the control valve 50
No power is supplied to the plungers 82 and 83, and there is no electromagnetic bias to the plungers 82 and 83. Therefore, in the opening / closing valve mechanism 60, the opening spring 66
, The opening / closing valve hole 63 is fully opened, and the adjustment valve mechanism 72 is closed by the action of the closing spring 75 in the adjustment valve mechanism 70. When this operation stop state continues for a long time, the pressures in the respective chambers 5, 21, 22 of the compressor are equalized, and the swash plate 12 is held at the minimum inclination angle by the urging action of the inclination reduction spring 16.

When the room temperature detected by the room temperature sensor 35 exceeds the temperature set by the room temperature setting unit 36 under the ON state of the air conditioner operation switch 37, the control computer C energizes the solenoid coil 43 of the electromagnetic clutch to perform the engine operation. The compressor is operated by connecting E to the compressor, and the coil 85 of the control valve 50 is energized. By supplying power to the coil 85, the open / close plunger 82 is electromagnetically attracted to the fixed core 84, and the open / close valve body 64 closes the open / close valve hole 63 against the downward biasing force of the open spring 66 (see FIG. 2). The air supply passage 28 is completely closed.

Further, by supplying power to the coil 85, an electromagnetic attractive force corresponding to the supply current value is generated between the opening / closing plunger 82 and the adjusting plunger 83. This electromagnetic attraction force acts as a force in the direction of increasing the opening degree of the valve hole 72 (hereinafter referred to as “withdrawal valve opening degree”) against the urging force of the closing spring 75, via the adjusting rod 74 via the adjusting rod 74. 73. An operating connection is established between the adjustment plunger 83, the adjustment valve body 73, and the bellows 76 at least under the excitation state of the coil 85. And the regulating valve chamber and pressure sensing chamber 71
The bellows 76 is displaced in accordance with the fluctuation of the suction pressure Ps introduced into the valve, and affects the positioning of the adjustment valve body 73. In other words, the adjusting valve mechanism 70 opens the valve on the extraction side based on at least the balance between the electromagnetic urging force received by the adjusting plunger 83, the urging force of the closing spring 75, and the urging force of the bellows 76 reflecting the suction pressure Ps. Determine the degree. Except for the fact that the electromagnetic biasing force of the adjustment plunger 83 can be varied by externally applied power control, the adjustment valve mechanism 70 functions as a normal internal control valve that autonomously adjusts the opening in response to the suction pressure Ps. I do. Even when the coil 85 is energized, the positioning operation of the on-off valve body 64 of the on-off valve mechanism 60 and the positioning operation of the adjustment valve body 73 of the adjustment valve mechanism 70 do not depend on each other, but are independent of each other.

When the cooling load is large: As the cooling load increases, the outlet pressure of the evaporator 33 (that is, the suction pressure P
s) gradually increases, for example, the difference between the detected room temperature of the room temperature sensor 35 and the set temperature of the room temperature setting device 36 increases.
At this time, in order to secure the discharge capacity of the compressor corresponding to the increasing cooling load, the control computer C changes the supply current value to the coil 85 to change the set suction pressure Pset based on the detected room temperature and the set room temperature. Control. Specifically, the supply current value is increased as the detected room temperature is higher, and the urging force of the adjustment valve body 73 in a direction to increase the opening degree of the extraction side valve is increased. This means that the set suction pressure Pset of the control valve 50 is reduced and induced (or reset). Therefore, the adjustment valve mechanism 70 reduces the suction pressure Ps lower than the current level by increasing the supply current value to the coil 85. Work to achieve. That is, if the opening degree of the extraction side valve is increased by the autonomous operation of the regulating valve mechanism 70, the amount of refrigerant gas extracted from the crank chamber 5 to the suction chamber 21 via the bleed passage 27 increases. On the other hand, the refrigerant gas flowing from the discharge chamber 22 into the crank chamber 5 via the air supply passage 28 is blocked by the on-off valve mechanism 60. Therefore, the crank pressure Pc decreases. or,
In a state where the cooling load is large, the gas pressure sucked into the cylinder bore 1a, that is, the suction pressure Ps is relatively high, and the difference between the internal pressure of the cylinder bore 1a and the crank pressure Pc becomes small. Therefore, the inclination angle of the swash plate 12 increases.

When the opening of the withdrawal valve of the regulating valve mechanism 70 is maximized, the cross-sectional area of the bleed passage 27 is maximized, and the maximum amount of refrigerant gas flows from the crank chamber 5 into the suction chamber 21 via the bleed passage 27. Is extracted. Then, the crank pressure Pc becomes substantially equal to the pressure of the suction chamber 21 (suction pressure Ps), and the swash plate 2
The inclination angle of 1 becomes maximum and the discharge capacity becomes maximum. In this maximum discharge capacity state, the pressure in the discharge chamber 22 (discharge pressure Pd) may increase significantly due to fluctuations in the condensation capacity of the condenser 31 of the external refrigerant circuit 30. In this state,
The high discharge pressure Pd is introduced into the on-off valve chamber 61 of the on-off valve mechanism 60, and this high discharge pressure Pd acts on the on-off valve body 64. However, in this control valve 50, the opening / closing rod 6 connecting the opening / closing valve body 64 and the opening / closing plunger 82 is provided.
5 is substantially equal to the opening area S2 of the on-off valve hole 63. For this reason, considering the projected area of the on-off valve body 64 in the movable direction, that is, the pressure receiving area of the on-off valve body 64, in a state where the on-off valve body 64 closes the on-off valve hole 63, both sides of the on-off valve body 64 in the movable direction are closed. The pressure receiving areas are almost equal. As a result, in the movable direction of the on-off valve body 64, the pressure acting on the on-off valve body 64 is almost completely canceled, and the operation of the on-off valve body 64 can be performed without being affected by the discharge pressure Pd and the crank pressure Pc. Become.

When the cooling load is small: As the cooling load decreases, the outlet pressure (ie, Ps) of the evaporator 33 gradually decreases. For example, the difference between the detected temperature of the room temperature sensor 35 and the set temperature of the room temperature setter 36 is set. Becomes smaller. At this time, in order to make the discharge capacity of the compressor appropriate for the cooling load that is decreasing, the control computer C sets the set suction pressure P
The supply current value to the coil 85 is controlled to change the set. Specifically, the lower the detected room temperature, the smaller the supply current value, and the adjustment valve body 73 in a direction to increase the opening degree of the extraction side valve.
Reduce the biasing force of This means that the set suction pressure Pset of the control valve 50 is increased and induced (or reset). That is, if the opening degree of the extraction side valve is reduced by the autonomous operation of the regulating valve mechanism 70, the bleed passage 27
, The amount of the refrigerant gas extracted into the suction chamber 21 via the air passage decreases, and the crank pressure Pc tends to increase. Further, when the cooling load is small, the gas pressure sucked into the cylinder bore 1a, that is, the suction pressure Ps is relatively low, and the difference between the internal pressure of the cylinder bore 1a and the crank pressure Pc increases. For this reason,
The inclination angle of the swash plate 12 becomes small.

When approaching a state where there is no cooling load, the temperature of the evaporator 33 gradually decreases and approaches a temperature at which frost occurs. When the temperature detected by the temperature sensor 34 becomes equal to or lower than the set temperature (a temperature reflecting a situation where frost is likely to occur in the evaporator 33), the control computer C stops supplying current to the coil 85. Then, the electromagnetic attraction force between the fixed iron core 84 and the opening and closing plunger 82 and between the opening and closing plunger 82 and the adjustment plunger 83 disappears, and the opening and closing valve mechanism 60 fully opens the air supply passage 28 by the urging action of the opening spring 66. On the other hand, the adjustment valve mechanism 70 brings the bleed passage 27 into a fully closed state by the urging action of the closing spring 75. As a result, a large amount of high-pressure refrigerant gas in the discharge chamber 22 is supplied to the crank chamber 5 through the air supply passage 28, the crank pressure Pc increases, the swash plate 12 shifts to the minimum tilt state, and the air conditioner cools. Operation is suppressed. Note that, even when the air conditioner operation switch 37 is turned off, the control computer C stops the energization of the coil 85 and shifts the swash plate 12 to the minimum tilt state.

When the suction pressure Ps rises while the solenoid mechanism 80 is demagnetized: the suction pressure Ps reaches the regulating valve chamber / pressure sensing chamber 71 via the bleed passage 27 as a pressure detection passage. , The bellows 7 reflecting the height of the suction pressure Ps
6 is displaced in the contraction direction (upward). Here, the pressure sensing rod 78 and the bellows connection cylinder 77 are configured to be able to contact and separate from each other, and the closing spring 75 constantly biases the adjustment valve body 73 downward. Therefore, the operative connection between the pressure-sensitive rod 78 and the bellows 76 is canceled with the contraction of the bellows 76, and the transmission of the displacement of the bellows 76 to the adjustment valve body 73 is interrupted. Therefore, even if the suction pressure Ps increases in a state where the solenoid mechanism 80 is demagnetized, the adjustment valve mechanism 70 can maintain the adjustment valve hole 72 in the closed state without being affected by the suction pressure Ps. .

When the swash plate 12 is at the minimum inclination position while the air conditioner operation switch 37 is ON,
When the room temperature rises (the cooling load increases), the room temperature sensor 35
The detected room temperature exceeds the set temperature of the room temperature setting device 36. Then, the control computer C commands the excitation of the solenoid mechanism 80 based on the temperature change. Solenoid mechanism 80
With the excitation, the air supply passage 28 is closed by the opening / closing valve mechanism 60 and the bleed passage 27 is opened by the adjustment valve mechanism 70, the crank pressure Pc gradually decreases, and the swash plate 12 returns to the direction of increasing the tilt angle.

As described above, the opening / closing valve mechanism 6 of the control valve 50
0 and the operation of the regulating valve mechanism 70 are performed by the solenoid mechanism 8.
It is controlled by supplying and stopping the current to the zero coil 85. In particular, the set suction pressure Pset, which is a target value for controlling the valve opening of the adjusting valve mechanism 70 (the opening of the valve on the extraction side), can be changed as appropriate by controlling the value of the current supplied to the coil 85. Then, the compressor adjusts the swash plate 12 so that the actual suction pressure Ps approaches and maintains the set suction pressure Pset.
Is changed to change the discharge capacity.

(Effects) According to the present embodiment, the following effects can be obtained. In the capacity control valve 50, an opening / closing valve mechanism 60 for controlling the opening and closing of the air supply passage 28 and an adjusting valve mechanism 70 for arbitrarily adjusting the opening degree of the bleed passage 27 are provided in the same valve housing 51. Built in. For this reason, according to the control valve 50, unlike the conventional compressor in which the on-off valve and the adjustment valve are configured as separate components and assembled separately in the compressor, two valves (on-off valve and adjustment valve) are used. Need not be separately prepared, and the capacity control configuration of the compressor can be simplified and manufactured at a lower cost than before. Further, since the opening / closing valve mechanism 60 and the regulating valve mechanism 70 are integrated, a relatively small installation space for the capacity control valve 50 is required, and the assembling to the compressor is easy, and the compressor is downsized. To contribute.

In the control valve 50, the opening / closing plunger 82 of the opening / closing valve mechanism 60 and the adjusting plunger 8 of the adjusting valve mechanism 70
Since one coil 85 is shared for both of the three, the structure of the control valve can be simplified.

In the control valve 50, the opening / closing valve body 64 and the plunger 82, and the adjusting valve body 73 and the plunger 83 are connected by the opening / closing rod 65 and the adjusting rod 74, respectively, and one of the cylindrical opening / closing rods is provided. The other adjustment rod 74 is inserted into the inside 65 so as to be relatively movable.
Therefore, the two valve bodies 64 and 73 are connected to their plungers 8.
2,83 can be placed close to one side
The control valve 50 including the two valve mechanisms 60 and 70 can be prevented from increasing in size in the axial direction.

In the control valve 50 of the present embodiment, since the solenoid mechanism 80 is provided so as to be offset to one end of the valve housing 51, the control valve 50 is mounted on the rear housing 4 of the compressor as shown in FIG. When assembled, the solenoid mechanism 80 is exposed outside the rear housing 4. Therefore, wiring from the outside to the coil 85 of the solenoid mechanism 80 in the exposed state is facilitated.

The adjustment valve body 73 and the bellows (pressure-sensitive member) 76 constituting the adjustment valve mechanism 70 of the control valve 50 can be connected and separated based on the insertion relationship between the connecting cylinder 77 and the pressure-sensitive rod 78. Have been. For this reason, even when the suction pressure Ps increases and the bellows 76 contracts and displaces when the power supply to the coil 85 is stopped, the adjustment valve body 73 operates the closing spring 75 without being affected by the displacement of the bellows 76. Thus, the adjustment valve hole 72 can be held at the closed position.

The sectional area S1 of the opening / closing rod 65 connecting the opening / closing valve body 64 and the opening / closing plunger 82 and the discharge chamber 22
Opening area S2 of the opening / closing valve hole 63 connecting the valve and the crank chamber 5
And the opening / closing valve body 64 is made
When the valve is closed, the pressure receiving areas on both sides in the movable direction of the on-off valve body 64 become substantially equal, so that the pressure acting on the on-off valve body 64 can be almost offset. Therefore, even when the discharge pressure Pd acting on the on-off valve body 64 is greatly increased, the on-off valve body 64 can be smoothly moved without being affected by the discharge pressure Pd and the crank pressure Pc.

The regulating valve body 7 constituting the regulating valve mechanism 70
Since the pressure sensing member 3 and the pressure sensing member 76 are provided in the same adjustment valve chamber and pressure sensing chamber 71 to which the suction pressure Ps is applied, the number of rooms defined in the control valve is reduced as compared with the related art, and the hole machining and rod clearance management are reduced. The labor is greatly reduced, which is advantageous in terms of manufacturing cost.

In the extraction side control in which the swash plate angle is adjusted by mainly controlling the amount of gas released from the crank chamber 5, it is necessary to constantly supply the high-pressure refrigerant gas to the crank chamber 5 stably. This is a prerequisite for ensuring controllability (variable control of the discharge capacity). In this regard, in the variable displacement compressor of FIG. 1, a communication path 29 is formed as an auxiliary air supply path connecting the discharge chamber 22 and the crank chamber 5, and a fixed throttle 29 a is provided in the communication path 29. Have been. For this reason, even in a state where the air supply passage 28 is closed by the opening / closing valve mechanism 60 and the opening of the bleeding passage 27 (opening side valve opening) is adjusted by the adjusting valve mechanism 70, the communication passage 2 with the throttle 29 a is also provided.
A predetermined amount of refrigerant gas is constantly supplied from the discharge chamber 22 to the crank chamber 5 through the pipe 9. For this reason, the crank pressure Pc is always maintained at or above the predetermined pressure during the operation of the compressor.
The variable controllability of the discharge capacity by the adjusting valve mechanism 70 is not impaired.

(Another Example) The embodiment of the present invention may be modified as follows. The internal structure of the regulating valve chamber / pressure sensing chamber 71 is changed as shown in FIG. 3 or FIG. In FIG. 3, the pressure-sensitive rod 78 is
And the closing spring 75 is connected to the valve chamber 7.
1 is disposed between the ceiling wall 1 and a spring seat 73 a formed at the head of the regulating valve body 73. In addition, similarly to the control valve of FIG. On the other hand, in FIG. 4, a closing spring 75 is interposed between the ceiling wall of the valve chamber 71 and the base end (upper end) of the bellows 76, and the adjustment valve body 73 is fixed to the front end (lower end) of the bellows 76. Have been. Even if the internal structure of the regulating valve chamber / pressure sensing chamber 71 in the control valve 50 of FIG. 2 is changed as shown in FIG. 3 or FIG. 4, the same operation and effect as described above are exerted.

The adjusting rod 74 of the adjusting valve mechanism 70 is formed in a cylindrical shape, and the opening / closing rod 65 of the opening / closing valve mechanism 60 is inserted into the adjusting rod 74 so as to be relatively movable. ○ A diaphragm is used as a pressure-sensitive member used in the adjustment valve mechanism 70.

The pressure-sensitive rod 78 in FIGS. 2 and 3
And the connecting cylinder 77. The displacement control valve 50 is applied to a clutchless variable displacement compressor (compressor of a type that directly transmits power from an external drive source to the drive shaft 6 without interposing a clutch mechanism such as an electromagnetic clutch). To do.

(Supplementary note) A variable displacement compressor in which the control valve according to any one of claims 1 to 5 is incorporated,
Between the discharge pressure region of the compressor and the crank chamber, an air supply passage 28 having an opening / closing valve mechanism 60 for the control valve interposed therebetween.
In addition, a variable displacement compressor provided with an auxiliary air supply passage 29 having a fixed throttle 29a. According to this configuration, even when the air supply passage is closed by the on-off valve mechanism,
Since a predetermined amount of refrigerant gas is supplied from the discharge pressure region to the crank chamber via the auxiliary air supply passage, the variable controllability of the discharge capacity is not impaired.

[0052]

As described in detail above, the control valve of the present invention is applicable to a general variable displacement compressor having no shut-off body and has a simpler structure than a conventional control valve. It has an excellent effect that it is easy to manufacture and advantageous in cost.

[Brief description of the drawings]

FIG. 1 is a sectional view of a variable displacement compressor according to one embodiment.

FIG. 2 is a sectional view of a displacement control valve.

FIG. 3 is a partial sectional view showing another example of the capacity control valve.

FIG. 4 is a partial sectional view showing another example of the capacity control valve.

[Explanation of symbols]

5: crank chamber, 12: swash plate, 21: suction chamber (suction pressure area), 22: discharge chamber (discharge pressure area), 27: bleed passage
28 ... air supply passage, 40 ... electromagnetic clutch, 50 ... control valve,
51 ... valve housing, 60 ... opening and closing valve mechanism, 63 ... opening and closing valve hole, 64 ... opening and closing valve body, 65 ... opening and closing rod, 66 ... opening spring, 70 ... adjusting valve mechanism, 71 ... adjusting valve chamber and pressure sensing chamber (inhalation) 72 ... adjusting valve hole, 73 ... adjusting valve body, 74 ... adjusting rod, 75 ... closing spring, 76 ... bellows (pressure sensing member), 80 ... solenoid mechanism, 82 ... opening / closing plunger 1 ... plunger; 83 ... adjustment plunger (second plunger); 85 ... coil; E ... vehicle engine (external drive source); S1 ... cross-sectional area of rod; S2 ... opening area of valve hole.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Taku Yasutani 2-1-1 Toyota-cho, Kariya-shi, Aichi Pref. Inside Toyota Industries Corporation (72) Inventor Ryo Matsubara 2-1-1 Toyota-cho, Kariya-shi, Aichi Pref. F-term in Toyota Industries Corporation (Reference) 3H045 AA04 AA10 AA27 BA19 CA09 CA24 DA25 EA16 EA17 EA26 EA33 3H059 AA06 BB22 BB40 CC06 CD05 CF14 DD07 DD13 EE01 FF12 FF15 3H076 AA06 BB41 CC94 DB23 CC93 DA93 DB24 DB32 DC02 DD03 DD09 EE34 EE48 GA15 GB08 KK23

Claims (5)

[Claims] 1. A control valve for use in a variable displacement compressor capable of changing a tilt angle of a swash plate based on control of an internal pressure of a crank chamber and adjusting a discharge capacity, wherein a compression valve is provided in a valve housing of the control valve. An on-off valve mechanism for controlling the opening and closing of an air supply passage communicating the discharge pressure region of the compressor with the crank chamber, and an arbitrarily adjusting an opening degree of a bleed passage connecting the suction pressure region of the compressor and the crank chamber. An adjusting valve mechanism, which is incorporated so as to be independently operable, wherein the on-off valve mechanism includes an on-off valve hole forming a part of the air supply passage, an on-off valve body for opening and closing the valve hole, and the valve. An opening spring for urging the body in a direction away from the on-off valve hole, and an electromagnetic force coupled to the on-off valve body for closing the on-off valve hole regardless of the urging action of the opening spring. A first plunger for biasing, said regulating valve The mechanism includes an adjustment valve hole that constitutes a part of the bleed passage, an adjustment valve body that adjusts an opening degree of the valve hole, and a closing spring that urges the valve body in a direction approaching the adjustment valve hole. A pressure-sensitive member capable of pressing the adjustment valve body in a direction approaching the adjustment valve hole in accordance with a suction pressure; and an electromagnetic valve connected to the adjustment valve body and separating the valve body from the adjustment valve hole. A second plunger for biasing, wherein the adjusting valve body and the pressure-sensitive member constituting the adjusting valve mechanism are disposed in the same chamber to which suction pressure is applied, and the first and second plungers are provided.
A control valve for a variable displacement compressor, wherein one coil is provided for a plunger, and the on-off valve body and the adjustment valve body are simultaneously electromagnetically energized by energizing the coil. 2. An on-off valve body of the on-off valve mechanism and a first plunger are connected by a rod, and an adjustment valve body of the adjustment valve mechanism and a second plunger are connected by another rod. While one of them is formed in a cylindrical shape,
2. The control valve for a variable displacement compressor according to claim 1, wherein the other rod is inserted into the one rod so as to be relatively movable. 3. The adjustment valve body of the adjustment valve mechanism and a pressure-sensitive member are connected so as to be able to contact and separate from each other.
The control valve for a variable displacement compressor according to item 1. 4. An on-off valve hole of the on-off valve mechanism has one end communicating with a discharge pressure region and the other end communicating with a crank chamber, and a cross-sectional area of a rod connecting the on-off valve body and a first plunger is determined by the on-off valve hole. The control valve of the variable displacement compressor according to any one of claims 1 to 3, wherein the opening area is substantially equal to the opening area of the compressor. 5. The variable displacement compressor according to claim 1, further comprising a clutch for selectively transmitting power of an external drive source to the compressor. A control valve for the variable displacement compressor according to claim 1.