JP2002039059A - Electromagnetic actuator, valve and flow control valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electromagnetic actuator which can be miniaturized and can increase thrust with the same power consumption. SOLUTION: The control valve equipped with the electromagnetic actuator 71 that is equipped with a cylindrical case 73 in which flange 73a is installed, a coil part 74, a center post 75, a plate 76, a sleeve 77 and a plunger 78. The sleeve 77 is made of nonmagnetic material and formed a hollow cylinder with basal plain whose internal diameter is the same diameter as the inner flange 73a, and a guard 77a is crooked outside, and fixed at the step part which is formed inside flange 73a at the guard 77a. The coil part 74 is equipped with an inner cylinder whose internal diameter is same as the sleeve 77 outer diameter, and the inner cylinder is installed in the case 73 with the condition that is inlaid by the sleeve 77 and held tight between the inner flange 73 and the plate 76. The biasing spring is installed in the plunger 79 between the plunger 78 and the center post.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a displacement control valve provided in an electromagnetic actuator, a valve, and a variable displacement compressor.

[0002]

2. Description of the Related Art An electromagnetic actuator in which a plunger is reciprocated, as shown in FIG.
1 is a cylindrical case 173 having an inner flange 173a formed at one end, a coil member 174, a center post 175,
Plate 176, sleeve 177 and plunger 178
It has. The case 173, the center post 175 and the plunger 178 are formed of a magnetic material,
Is formed of a non-magnetic material. The sleeve 177 is fixed to the inner peripheral surface of the inner flange 173a of the case 173 by brazing at the outer peripheral surface of the opening end. The plunger 178 is urged by the urging spring 180 in a direction away from the center post 175, and the coil member 1
When electricity is supplied to 74, it is moved to the center post 175 side by a suction force. A rod or valve is connected to the plunger 178 for use.

In addition, a swash plate type variable displacement compressor widely used as a compressor generally used in a vehicle air conditioner includes an outlet pressure of an evaporator provided in an external refrigerant circuit (or a compressor correlated therewith). (A suction pressure Ps) is maintained at a predetermined target value (set pressure). The capacity control mechanism performs feedback control of the discharge capacity of the compressor, that is, the swash plate angle, using the outlet pressure of the evaporator (or the suction pressure Ps correlated therewith) as a control index so that the refrigerant discharge amount matches the magnitude of the cooling load. I do.

[0004] A typical example of the displacement control mechanism is a displacement control valve called an internal control valve. In the internal control valve, the outlet pressure Ps' or suction pressure Ps of the evaporator is sensed by a pressure-sensitive member such as a bellows or a diaphragm, and the valve opening is adjusted by using the displacement operation of the pressure-sensitive member for positioning the valve body. Thus, the pressure (crank pressure Pc) of the swash plate chamber (crank chamber) is adjusted to adjust the swash plate angle.

Further, since a simple internal control valve which can have only a single set pressure cannot perform complicated displacement control for power saving, a control valve which can control the valve opening degree by an external electric signal ( An external control valve is used as a displacement control valve (for example, Japanese Patent Application Laid-Open Nos. 9-268973 and 2000-18420).

[0006]

The thrust of the electromagnetic actuator is generated by the electromagnetic force of the magnetic field generated when the coil member 174 is energized.
6. The greater the amount of magnetic flux passing through the plunger 178 and the center post 175, the greater the magnitude. However, in the conventional electromagnetic actuator, one end of the sleeve 177 is connected to the case 173.
Is fixed to the inner peripheral surface of the inner flange 173a, and the length of the fixed portion in the axial direction is several meters in order to secure airtightness.
m or more is required. Further, since the sleeve 177 is made of a non-magnetic material, the sleeve 177 serves as a resistor for passing magnetic flux. As a result, when the magnetic flux changes the course from the center post 175 to the case 173, the leakage of the magnetic flux easily occurs, and the thrust decreases. If the axial length of the inner flange 173a is increased, leakage of magnetic flux is less likely to occur, but there is a problem that the size of the electromagnetic actuator increases.

[0007] Further, it is desired that the displacement control valve used in the variable displacement compressor be miniaturized so that the space for mounting the variable displacement compressor on the vehicle can be reduced as much as possible. In the conventional electromagnetic actuator, the center post 17 is used.
5 so that the ratio of the cross-sectional area S1 of the portion corresponding to the sleeve 177 to the cross-sectional area S2 of the portion corresponding to the outer peripheral surface of the coil member 174 of the case 173 is approximately S1: S2 = 0.7: 1. Since it is formed, there is a problem that local magnetic saturation occurs and the thrust decreases.

The present invention has been made in view of the above problems, and a first object of the present invention is to provide an electromagnetic actuator capable of improving the thrust with the same power consumption and reducing the size. It is to provide a valve.
The second object is to increase the size of the capacity control valve without increasing the size.
It is an object of the present invention to provide a displacement control valve of a displacement variable compressor that can improve the response of displacement control operation.

[0009]

In order to achieve the first object, according to the first aspect of the present invention, a coil member is disposed inside a cylindrical magnetic material case having an inner flange. An electromagnetic actuator in which a cylindrical sleeve made of a non-magnetic material is disposed inside the coil member, and a center post and a plunger are disposed inside the sleeve, wherein the center post is formed of an inner flange of the case. The sleeve is arranged so as to be in contact with the inner peripheral surface, and the sleeve has a flange portion bent outward at one end and fixed to the inner surface of the inner flange of the case.

In the present invention, unlike the conventional sleeve having a configuration in which the opening end side extends straight, almost the entire inner peripheral surface of the inner flange of the case comes into contact with the center post. As a result, when the magnetic flux changes its course from the center post to the case, the magnetic flux is leaked and prevented. Therefore, the suction force (thrust) acting on the plunger with the same supply current (power) increases.

According to a second aspect of the present invention, in the first aspect of the present invention, a cross-sectional area of a portion of the center post corresponding to the sleeve and a cross-sectional area of a portion of the case corresponding to an outer peripheral surface of the coil member are provided. The ratio to the cross-sectional area is formed to be approximately 1: 1. Note that a ratio of approximately 1: 1 means that the difference in cross-sectional area is about ± 10%.

Therefore, according to the present invention, unlike the conventional electromagnetic actuator, local magnetic saturation can be reduced, and the thrust is improved. According to a third aspect of the present invention, there is provided a valve element driven by the electromagnetic actuator according to the first or second aspect. Therefore, in the present invention, the driving of the valve body is performed smoothly even with the same power consumption.

In order to achieve the second object, according to the invention described in claim 4, a piston housed reciprocally in a cylinder bore formed in a housing, a crank chamber partitioned and formed in the housing, A cam plate that is housed in the crank chamber and that is operatively connected to the piston to change the rotational motion of the drive shaft into a reciprocating motion of the piston and that changes a stroke of the piston by changing a tilt angle; A displacement control valve mounted on a variable displacement compressor in which the tilt angle of the cam plate is controlled by controlling pressure, wherein the valve chamber communicates via a valve hole with a control passage to be adjusted in opening. A valve body that is housed in the valve chamber and opens and closes the valve hole, and is connected to one side of the valve body via a pressure-sensitive rod, and the opening degree of the valve hole is changed according to the pressure of the fluid. Comprising a pressure-sensitive part for urging the valve body in the direction of reduction, and a solenoid rod driven by the electromagnetic actuator plunger while being connected to the other side of the valve body, according to claim 1 as said electromagnetic actuator
Alternatively, the electromagnetic actuator according to claim 2 is used. Note that the inclination angle of the cam plate means an angle formed between a virtual plane orthogonal to the drive shaft and the cam plate.

The displacement control valve of the present invention is used for a variable displacement compressor that changes the displacement by controlling the pressure in a crank chamber. The pressure of the valve chamber, the pressure of the pressure sensing portion, and the pressure by the electromagnetic force via the plunger act on the valve body. Then, the opening degree of the control passage, that is, the valve body position is determined by the balance between them. The electromagnetic force is controlled by the amount of current (power) supplied to the coil member. Since the electromagnetic actuator uses the one described in claim 1 or claim 2,
The capacity control valve can be reduced in size.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is embodied in a displacement control valve of a clutchless variable displacement compressor used in a vehicle air conditioner will be described with reference to FIGS.

First, the configuration of the clutchless variable displacement compressor will be described. As shown in FIG. 2, the front housing 11 is fixedly joined to the front end of the cylinder block 12. The rear housing 13 includes the cylinder block 12
Is fixedly connected to the rear end through a valve / port forming body 14. The crank chamber 15 is defined by being surrounded by the front housing 11 and the cylinder block 12.
The drive shaft 16 is rotatably supported between the front housing 11 and the cylinder block 12 so as to pass through the crank chamber 15. The pulley 17 is rotatably supported by the front housing 11. The pulley 17 is connected to a drive shaft 16, and is directly connected to an engine 20 of the vehicle as an external drive source without a clutch mechanism such as an electromagnetic clutch via a belt 19 wound around an outer peripheral portion thereof. I have.

The rotary support (lag plate) 21 is fixed to the drive shaft 16 in the crank chamber 15, and a thrust bearing 22 is interposed between the rotary support 21 and the inner wall surface of the front housing 11. The swash plate 23 as a cam plate is supported so as to be slidable and tiltable with respect to the drive shaft 16 in the direction of the axis L thereof. The hinge mechanism 24 is interposed between the rotary support 21 and the swash plate 23. The swash plate 23 can be tilted with respect to the axis L of the drive shaft 16 and can rotate integrally with the drive shaft 16 by the hinge mechanism 24. When the center of the radius of the swash plate 23 moves toward the cylinder block 12, the inclination angle of the swash plate 23 decreases. The inclination reducing spring 26 is interposed between the rotary support 21 and the swash plate 23. The inclination reduction spring 26 is
The swash plate 23 is urged in the direction of decreasing the inclination angle. The maximum inclination angle of the swash plate 23 is defined by the contact with the rotating support 21.

The housing hole 27 extends through the center of the cylinder block 12 in the direction of the axis L of the drive shaft 16.
The blocking body 28 has a closed cylindrical shape and is slidably housed in the housing hole 27. The suction passage opening spring 29 is interposed between the end surface of the housing hole 27 and the blocking member 28, and is connected to the blocking member 2.
8 is urged toward the swash plate 23 side.

The drive shaft 16 is inserted into the inside of the blocking body 28 with its rear end. Radial bearing 3
Numeral 0 is interposed between the rear end of the drive shaft 16 and the inner peripheral surface of the blocking body 28, and is slidable with respect to the driving shaft 16 in the direction of the axis L with the blocking body 28.

The suction passage 32 constituting the suction pressure region is formed at the center of the rear housing 13 and the valve / port forming body 14. The suction passage 32 communicates with the housing hole 27, and a positioning surface 33 is formed around the opening on the front surface of the valve / port forming body 14. The blocking surface 34 is formed on the distal end surface of the blocking member 28 and is moved toward and away from the positioning surface 33 by the movement of the blocking member 28. When the blocking surface 34 is in contact with the positioning surface 33, communication between the suction passage 32 and the inner space of the housing hole 27 is blocked by the sealing action between the two surfaces 33 and 34.

The thrust bearing 35 is interposed between the swash plate 23 and the blocking body 28 and is slidably supported on the drive shaft 16. The thrust bearing 35 is urged by the suction passage opening spring 29 and is always held between the swash plate 23 and the blocking body 28. Then, as the swash plate 23 tilts toward the blocking body 28, the tilt of the swash plate 23 is transmitted to the blocking body 28 via the thrust bearing 35. Accordingly, the blocking body 28 is moved toward the positioning surface 33 against the urging force of the suction passage opening spring 29, and the blocking body 28 contacts the positioning surface 33 with the blocking surface 34. With the blocking surface 34 in contact with the positioning surface 33, the blocking member 2
Further tilting of the swash plate 23 is restricted via 8, and in this restricted state, the swash plate 23 has a minimum tilt angle slightly larger than 0 °.

The cylinder bore 12a is the cylinder block 1.
2 is formed through. The single-headed piston 36 is housed in the cylinder bore 12a. The piston 36 is moored to the outer peripheral portion of the swash plate 23 via a shoe 37,
The swash plate 23 is reciprocated back and forth in the cylinder bore 12a by the rotational movement.

The suction chamber 38 forming the suction pressure region and the discharge chamber 39 forming the discharge pressure region are formed in the rear housing 13 respectively. The suction port 40, the suction valve 41, the discharge port 42, and the discharge valve 43
It is formed on the port forming body 14. And the suction chamber 3
The refrigerant gas of No. 8 is sucked into the cylinder bore 12a via the suction port 40 and the suction valve 41 by the reciprocating operation of the piston 36. The refrigerant gas sucked into the cylinder bore 12a is compressed to a predetermined pressure by the forward movement of the piston 36, and is discharged to the discharge chamber 39 via the discharge port 42 and the discharge valve 43.

The suction chamber 38 communicates with the receiving hole 27 through a through hole 45 formed through the valve / port forming body 14. Then, when the blocking body 28 comes into contact with the positioning surface 33 with the blocking surface 34, the communication port 45 is blocked from the suction passage 32. The passage 46 is formed in the axis of the drive shaft 16,
The crank chamber 15 and the inner space of the blocking body 28 communicate with each other via the passage 46. The pressure release port 47 penetrates the peripheral surface of the blocking body 28, and the internal space of the blocker 28 and the internal space of the housing hole 27 are communicated through the pressure releasing port 47.

The control passage 48 communicates the discharge chamber 39 on the upstream side with the crank chamber 15 on the downstream side. The control valve 49 is interposed on the control passage 48. Inspection passage 5
0 is formed between the suction passage 32 and the control valve 49.

The suction passage 32 for introducing the refrigerant gas into the suction chamber 38 and the discharge flange 51 for discharging the refrigerant gas from the discharge chamber 39 are connected by an external refrigerant circuit 52. The external refrigerant circuit 52 includes a condenser 53, an expansion valve 54, and an evaporator 55. The external refrigerant circuit 52 and the variable capacity compressor having the above-described configuration constitute a refrigeration circuit of the vehicle air conditioner.

The control computer 56 is provided with, for example, a cabin temperature obtained from a cabin temperature sensor 57 and a cabin temperature setting device 5.
An input current value is instructed to the drive circuit 60 on the basis of an external signal such as the set temperature from 8 and the rotational speed of the engine 20 of the vehicle obtained from the rotational speed sensor 59. The driving circuit 60
The instructed input current value is output to the control valve 49.

Next, the control valve 49 will be described in detail. As shown in FIG. 1, the control valve 49 is configured by joining an electromagnetic actuator 71 as a solenoid unit and a valve housing 72 as a valve unit.

The electromagnetic actuator 71 has a cylindrical case 73 having an inner flange 73a formed at one end, a coil member 74, a center post 75, a plate 76, and a sleeve 77.
And a plunger 78. The case 73, the center post 75 and the plunger 78 are made of a magnetic material, and the sleeve 77 is made of a non-magnetic material (stainless steel in this embodiment).

The inner diameter of the sleeve 77 is an inner flange 73a.
A flange 77a is formed to be bent outward at an open end, which is one end, while having the same bottomed cylindrical shape as the inner diameter of
The flange 77a is fixed to a step formed on the inner surface of the inner flange 73a. The coil member 74 has an inner cylindrical portion having the same inner diameter as the outer diameter of the sleeve 77, and is housed in the case 73 while being sandwiched between the inner flange 73 a and the plate 76 in a state where the inner cylindrical portion is externally fitted to the sleeve 77. ing.

Since the center post 75 plays a role of a fixed iron core, the center post 75 is fixed to the case 73 while being inserted from the inner flange 73a side to the sleeve 77 to an intermediate position thereof.
A plunger chamber 79 is defined by the front end surface of the center post and the sleeve 77. The plunger chamber 79 is disposed so that almost half is surrounded by the coil member 74. The plunger 78 is accommodated in the plunger chamber 79 so as to be able to reciprocate in the axial direction of the valve housing 72.
4. The biasing spring 80 moves the plunger 78 and the center post 75 in the plunger chamber 79.
It is interposed between and. The urging force of the urging spring 80 moves the plunger 78 away from the center post 75 (FIG. 1).
Below). The case 73 is formed such that the ratio of the cross-sectional area S1 of the portion corresponding to the sleeve 77 of the center post 75 to the cross-sectional area S2 of the portion corresponding to the outer peripheral surface of the coil member 74 of the case 73 is approximately 1: 1. ing.

The valve housing 72 includes a valve chamber 81, a valve element 82, a pressure sensing part 83, and a solenoid rod 84. The valve chamber 81 is defined between the valve housing 72 and the electromagnetic actuator 71. The valve chamber 81 communicates with the control passage 48 whose opening is to be adjusted through a valve hole 85. The valve element 82 is housed in the valve chamber 81 and opens and closes the valve hole 85. The valve hole 85 is opened in the valve chamber 81 so as to face the valve element 82. An end surface 82a of the valve body 82 facing the valve hole 85 is formed in a planar shape. Projection 8
2b protrudes from the end surface 82a of the valve body 82 and has a tapered shape with a small diameter on the valve hole 85 side. The valve hole 85 is formed so as to extend in the axial direction of the valve housing 72. The valve chamber 81 communicates with the crank chamber 15 via a valve chamber port 86 and a downstream side of the control passage 48.

The pressure-sensitive chamber 87 is defined at the tip of the valve housing 72. The pressure detection passage 50 is connected to a pressure sensing chamber 87. Therefore, the pressure sensing chamber 87 is communicated with the suction passage 32 via the pressure detection port 88 and the pressure detection passage 50. The bellows 89 as a pressure-sensitive member is provided in the pressure-sensitive chamber 8.
7. The setting spring 90 is provided in the bellows 89. Since the inside of the bellows 89 is almost in a vacuum state, the setting spring 90 sets an initial length while preventing the bellows 89 from being contracted by the atmospheric pressure, and attaches the valve spring 82 to the valve body 82 via a pressure-sensitive rod 91 described later. This is for applying a force (load).

The guide hole 92 of the pressure-sensitive rod 91 extends through the partition wall 72a of the valve housing 72 between the pressure-sensitive chamber 87 and the valve chamber 81. The guide hole 92 is formed continuously with the valve hole 85. The pressure-sensitive rod 91 is provided in the guide hole 9.
2 is slidably inserted into the bellows 89, and the tip thereof is fitted to the bellows 89. The pressure-sensitive rod 91 is formed integrally with the valve body 82 and operatively connects the bellows 89 and the valve body 82. The portion of the pressure-sensitive rod 91 that is continuous with the valve element 82 has a small diameter (a small-diameter portion 91a) in order to secure a passage for the refrigerant gas in the valve hole 85. The sectional area of the pressure-sensitive rod 91 is formed to be equal to the opening area of the valve hole 85. The pressure-sensitive chamber 87, bellows 89, setting spring 9
0 and the pressure-sensitive rod 91 constitute a pressure-sensitive part 83. That is, the pressure sensing portion 83 is connected to one side of the valve body 82 via the pressure sensing rod 91 and urges the valve body 82 in a direction in which the opening degree of the valve hole 85 changes according to the pressure of the fluid.

The port 93 is formed between the valve chamber 81 and the pressure-sensitive chamber 87 on the partition wall 72a of the valve housing 72. The port 93 is orthogonal to the valve hole 85.
The port 93 is connected to the discharge chamber 3 via the upstream side of the control passage 48.
9 is communicated. Therefore, the valve chamber port 86, the valve chamber 81, the valve hole 85, and the port 93 constitute a part of the control passage 48.

The plunger chamber 79 has a center post 75.
Is communicated with the valve chamber 81 through a guide hole 94 provided at the center of the valve chamber 81. The solenoid rod 84 is formed integrally with the valve body 82 and is slidably inserted into the guide hole 94. The end of the solenoid rod 84 opposite to the valve body 82 is fitted and fixed to the plunger 78. Therefore, the plunger 78 and the solenoid rod 84 are moved integrally. The urging spring 80 urges the valve body 82 through the solenoid rod 84 in the opening direction of the valve hole 85. That is, the biasing spring 80 functions as a forcible opening spring.

The peripheral surface of the solenoid rod 84 and the guide hole 9
The plunger chamber 79 has the same pressure atmosphere as the valve chamber 81, that is, the crank chamber pressure Pc atmosphere. In the plunger room 79, the plunger 7
1 between the upper space and the lower space in FIG. 1 through the gap between the inner wall surface of the plunger chamber 79 and the outer peripheral surface of the plunger 78. I have.

The valve section (the valve housing 7)
The configuration of 2) is a solenoid rod 8 that drives the valve element 82.
The control valve is basically the same as the control valve described in Japanese Patent Application Laid-Open No. 2000-18420 by the present applicant, except that 4 is directly connected to and driven by the plunger 78.

Next, the operation of the control valve 49 and the compressor will be described. With the air conditioner switch on,
When the detected temperature obtained from the cabin temperature sensor 57 is equal to or higher than the temperature set by the cabin temperature setting device 58, the control computer 56 commands the excitation of the electromagnetic actuator 71.
Then, a predetermined current is supplied to the coil member 74 via the drive circuit 60, and the action of magnetic flux passing through the case 73, the plate 76, the plunger 78, and the center post 75 causes
An attractive force (electromagnetic force) is generated between the center post 75 and the plunger 78 according to the input current value. This suction force is transmitted to the valve body 82 as a force in a direction in which the opening degree of the valve hole 85 decreases, against the urging force of the urging spring 80.

On the other hand, when the electromagnetic actuator 71 is in the excited state, the bellows 89 is displaced in accordance with the fluctuation of the suction pressure introduced from the suction passage 32 into the pressure sensing chamber 87 via the pressure detection passage 50. The bellows 89 responds to the suction pressure, and the displacement of the bellows 89 is transmitted to the valve body 82 via the pressure-sensitive rod 91. Accordingly, the opening of the valve hole 85 of the control valve 49 is determined by the balance between the urging force from the electromagnetic actuator 71, the urging force from the bellows 89 including the setting spring 90, and the urging force of the urging spring 80. .

Since the sleeve 77 is made of a non-magnetic material, it serves as a resistor for the passage of magnetic flux. However, the sleeve 77 is fixed to the inner flange 73a at the flange 77a on the opening end side. Accordingly, unlike the conventional sleeve 77 having a configuration in which the opening end side extends straight, the inner flange 73 of the case 73 is provided.
Substantially the entire inner peripheral surface of “a” comes into contact with the center post 75. As a result, when the magnetic flux changes its course from the center post 75 to the case 73, the magnetic flux does not easily leak, and the attractive force (thrust) acting on the plunger 78 with the same supply current (power) increases. The length of the case 73 and the center post 75 is made the same
When the shape was changed, the thrust increased by 10%.

The ratio of the cross-sectional area S1 of the portion corresponding to the sleeve 77 of the center post 75 to the cross-sectional area S2 of the portion corresponding to the outer peripheral surface of the coil member 74 of the case 73 is approximately 1: 1. Since it is formed, unlike the conventional electromagnetic actuator, local magnetic saturation can be reduced, and the thrust is improved. The thrust was improved by about 20% as compared with the case where the cross-sectional area of the center post was approximately 70% of the cross-sectional area of the case in which the sleeve was formed straight.

When the cooling load is large, the difference between the temperature detected by the cabin temperature sensor 57 and the temperature set by the cabin temperature setting device 58 increases. Control computer 56
Controls the input current value to change the set suction pressure based on the detected temperature and the set room temperature. The control computer 56 instructs the drive circuit 60 to increase the input current value as the detected temperature increases. Therefore, the suction force between the center post 75 and the plunger 78 is increased, and the urging force in the direction of decreasing the set value of the opening degree of the valve hole 85 by the valve body 82 is increased. Then, the opening and closing of the valve hole 85 by the valve element 82 is performed at a lower suction pressure. Accordingly, the control valve 49 operates to maintain a lower suction pressure by increasing the current value.

If the opening degree of the valve hole 85 becomes small, the discharge chamber 3
The amount of the refrigerant gas flowing into the crank chamber 15 from the control passage 9 through the control passage 48 decreases. On the other hand, crankcase 1
The refrigerant gas of No. 5 passes through the passage 46, the pressure release passage 47, and the accommodation hole 27.
And flows out to the suction chamber 38 through the communication port 45. For this reason, the pressure in the crank chamber 15 decreases. Further, when the cooling load is large, the pressure in the suction chamber 38 is also high, and the difference between the pressure in the crank chamber 15 and the pressure in the cylinder bore 12a becomes small. For this reason, the inclination angle of the swash plate 23 increases.

When the passage cross-sectional area in the control passage 48 is zero, that is, when the valve body 82 contacts the inner wall surface of the valve chamber 81 with the end face 82a and the valve hole 85 is completely closed, the discharge chamber 39 The supply of the high-pressure refrigerant gas to the crank chamber 15 is not performed. Then, the pressure in the crank chamber 15 becomes substantially the same as the pressure in the suction chamber 38, the inclination angle of the swash plate 23 becomes maximum, and the discharge capacity becomes maximum.

Conversely, when the cooling load is small, for example, the difference between the temperature detected by the vehicle interior temperature sensor 57 and the temperature set by the vehicle interior temperature setting device 58 becomes small. The control computer 56 instructs the drive circuit 60 to decrease the input current value as the detected temperature is lower. Therefore, the suction force between the center post 75 and the plunger 78 is weakened, and the urging force of the valve body 82 in the direction of decreasing the set value of the opening degree of the valve hole 85 is reduced. Then, the valve hole 85 is opened and closed at a higher suction pressure. Accordingly, the control valve 49 reduces the current value,
It operates to maintain a higher suction pressure.

When the opening of the valve hole 85 increases, the discharge chamber 3
The amount of the refrigerant gas flowing from 9 into the crank chamber 15 increases, and the pressure in the crank chamber 15 increases. When the cooling load is small, the pressure in the suction chamber 38 is low, and the difference between the pressure in the crank chamber 15 and the pressure in the cylinder bore 12a increases. For this reason, the inclination angle of the swash plate 23 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 evaporator temperature sensor falls below the set temperature, the control computer 56
Commands the drive circuit 60 to demagnetize the electromagnetic actuator 71. This set temperature reflects a situation in which frost is likely to occur in the evaporator 55. Then, the current supply to the coil member 74 is stopped, the electromagnetic actuator 71 is demagnetized, and the center post 75 and the plunger 78
And the suction force disappears.

Therefore, the valve element 82 is moved downward by the urging force of the urging spring 80. Then, the valve element 82 is connected to the valve hole 8.
5 is moved to the maximum open position. Therefore, a large amount of the high-pressure refrigerant gas in the discharge chamber 39 is supplied to the crank chamber 15 via the control passage 48, and the pressure in the crank chamber 15 increases. The pressure increase in the crank chamber 15 causes the swash plate 2
The tilt angle of No. 3 shifts to the minimum tilt angle.

The control computer 56 also controls the electromagnetic actuator 71 based on the off signal of the air conditioner switch.
Command of demagnetization. The declination of the electromagnetic actuator 71 also causes the tilt angle of the swash plate 23 to shift to the minimum tilt angle.

When the inclination angle of the swash plate 23 is minimized, the blocking body 2
8 comes into contact with the positioning surface 33 with the blocking surface 34, 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 38 is prevented. This swash plate 23
Is set to be slightly larger than 0 °. Therefore, even in the minimum inclination state, the refrigerant gas is discharged from the cylinder bore 12a to the discharge chamber 39. The refrigerant gas discharged from the cylinder bore 12a to the discharge chamber 39 passes through the control passage 48 and
Flows into The refrigerant gas in the crank chamber 15 passes through the passage 46,
The air flows into the suction chamber 38 through the pressure release port 47, the housing hole 27, and the port 45 inside the blocker 28. The refrigerant gas in the suction chamber 38 is sucked into the cylinder bore 12a and discharged again to the discharge chamber 39.

That is, in the state of the minimum inclination, the discharge chamber 39, the control passage 48, the crank chamber 15, the passage 4
6. Inside of the blocking body 28, the pressure release port 47, the housing hole 27, the port 45, the suction chamber 38 which is the suction pressure area, and the cylinder bore 1
A circulation passage passing through 2a is formed inside the compressor. The discharge chamber 39, the crank chamber 15, and the suction chamber 3
8, a pressure difference occurs. 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.

This embodiment has the following effects. (1) The center post 75 is the inner flange 7 of the case 73
3a is disposed in contact with the inner peripheral surface of the sleeve 3a.
A flange 77a bent outward at one end is fixed to the inner surface of the inner flange 73a. Therefore, when the magnetic flux changes the course from the center post 75 to the case 73, the leakage of the magnetic flux is less likely to occur, and the attractive force (thrust) acting on the plunger 78 with the same supply current (power) increases. If the thrust is the same, the inner flange 73
The length of “a” in the axial direction can be made shorter than before, and the length of the electromagnetic actuator 71 can be made shorter, so that downsizing can be achieved.

(2) The ratio of the sectional area S1 of the portion corresponding to the sleeve 77 of the center post 75 to the sectional area S2 of the portion corresponding to the outer peripheral surface of the coil member 74 of the case 73 is approximately 1: 1. Therefore, unlike the conventional electromagnetic actuator, local magnetic saturation can be reduced, and the thrust is improved. If the thrust is the same, the power consumption can be reduced.

(3) The valve element 82 is driven via the solenoid rod 84 by the electromagnetic actuator 71 having a large thrust. Therefore, the size of the displacement control valve can be reduced.

(4) The valve chamber 81 has a solenoid rod 84
The gap between the center post 75 and the center post 75 is formed as a pressure equalizing passage, so that the space is communicated with the plunger chamber 79. Accordingly, a dedicated equalizing passage for communicating the plunger chamber 79 with the crank chamber 15 is not required, and the manufacturing cost of the control valve 49 can be reduced.

(5) Since the pressure-sensitive rod 91, the valve element 82 and the solenoid rod 84 are integrally formed, the control valve 4
Nine components can be reduced, and the configuration can be simplified. (6) The projecting portion 82 b having a tapered shape is formed on the end face 8 of the valve body 82.
2A, the projection 82b enters the valve hole 85 with the valve hole 85 closed by the valve body 82. Therefore, when the valve hole 85 is opened and closed by the valve body 82, the projecting portion 82 b gradually changes the passage cross-sectional area of the valve hole 85.
As a result, it is possible to prevent the supply of the high-pressure compressed refrigerant gas to the crank chamber 15 from being suddenly started or stopped. Therefore, the capacity control characteristics of the compressor can be stabilized.

(7) When the electromagnetic actuator 71 is in the demagnetized state, the valve element 82 is moved by the urging spring 80 to the control passage 48.
The minimum discharge capacity state of the compressor is ensured. Therefore, the control valve 49 is suitable as a control valve of a clutchless variable displacement compressor in which the drive shaft 16 is constantly operatively connected to the engine 20 of the vehicle and the operation at the minimum discharge capacity is continued even when there is no cooling load. .

The embodiment is not limited to the above, and may be configured as follows, for example. Instead of the configuration in which the solenoid rod 84 is fitted and fixed to the plunger 78, a configuration in which the solenoid rod 84 abuts on the plunger 78 as in a control valve disclosed in JP-A-2000-18420. For example, as shown in FIG.
2, a flange 82c is formed, and the flange 82c and the valve chamber 8 are formed.
A force-release spring 96 is interposed between the inner wall of the sleeve 1 and the follower spring 97 between the plunger 78 and the bottom wall of the sleeve 77. The forcible opening spring 96 urges the valve body 82 to the opening side. The follower spring 97 moves the plunger 78 to the center post 75.
Side, that is, the valve body 82 is urged to the closing side via the solenoid rod 84. The urging force of the forcible release spring 96 is the follower spring 9
7 is set larger than the urging force. In this case, assembling becomes easier as compared with a configuration in which the solenoid rod 84 is fitted and fixed to the plunger 78.

The center post 75 is not necessarily the case 7
The center post 75 does not need to be fixed to the base 3 and may serve as a valve. For example, as shown in FIG. 3B, a large diameter portion 81 a equal to the outer diameter of the flange 75 a of the center post 75 is formed in the valve chamber 81 by the electromagnetic actuator 71. The pressure-sensitive chamber 87 and the large-diameter portion 81a are connected by a communication passage 98. The center post 75 is slidably provided along the sleeve 77, and functions as a valve for opening and closing the communication passage 98. The biasing spring 99 is interposed between the bottom surface of the valve chamber 81 and the flange 75a of the center post 75.
The center post 75 is urged in a direction to close the center post 75. The urging force of the urging spring 99 is set to be much stronger than the urging force of the urging spring 80.

Until the amount of current supplied to the coil member 74 reaches a predetermined value, the control valve 49 keeps the valve post 8 in a state where the center post 75 is held at the position where the communication passage 98 is closed.
2 is moved in a direction to close the valve hole 85. After the valve element 82 is disposed at the closed position, when the supply current to the coil member 74 is increased and the suction force acting on the center post 75 exceeds the sum of the urging forces of the urging springs 80 and 99, The center post 75 is moved to a position where the communication passage 98 is opened. As a result, the pressure sensing chamber 87 and the valve chamber 81 communicate with each other, and the crank chamber 15 communicates with the suction chamber 38. That is, the control valve 49 functions as a so-called inlet-side control valve that controls the supply amount of the refrigerant gas from the discharge chamber 39 to the crank chamber 15 by adjusting the opening degree of the valve hole 85 by the valve body 82.
When the center post 75 is moved to the closed position, it functions as a so-called vent-side control valve that guides the refrigerant gas from the crank chamber 15 to the suction chamber 38. Therefore, the displacement controllability is improved as compared with the case where the ejection displacement control is performed by only one of the insertion-side control and the ejection-side control.

The sectional area S 1 of the portion of the center post 75 corresponding to the sleeve 77 and the coil member 7 of the case 73
It is not necessary to form the ratio between the outer peripheral surface of No. 4 and the cross-sectional area S2 of the corresponding portion approximately 1: 1.

The variable displacement compressor may be applied to a control valve that opens and closes the control passage 48 simply by supplying a current to the coil member 74 without providing a pressure sensing portion as a displacement control valve. The present invention is not limited to the displacement control valve of the variable displacement compressor, and may be applied to a control valve applied to a fluid machine or a fluid circuit other than the compressor.

The present invention may be applied to a control valve of a variable displacement compressor with a clutch. Instead of the configuration in which the cam plate (swash plate 23) rotates integrally with the drive shaft 16, the present invention may be applied to a wobble type compressor in which the cam plate is supported to be rotatable relative to the drive shaft and swings. .

The present invention is not limited to an electromagnetic actuator for driving a valve body, but may be applied to an electromagnetic actuator for driving a drive unit other than a valve body with a solenoid rod. The technical ideas other than those described in the claims, which are grasped from the respective embodiments, will be described below.

(1) In the invention described in claim 4,
The pressure-sensitive part urges the valve body in a direction in which the opening degree of the valve hole decreases when the pressure increases in accordance with the pressure of the fluid. (2) The invention according to claim 4, further comprising an urging means for urging the valve body in a direction for forcibly opening the control passage when the electromagnetic actuator is demagnetized.

[0067]

As described in detail above, according to the first to third aspects of the present invention, the thrust can be improved with the same power consumption and the size can be reduced.

According to the fourth aspect of the invention, it is possible to improve the responsiveness of the capacity control operation without increasing the size of the capacity control valve.

[Brief description of the drawings]

FIG. 1 is a sectional view of a displacement control valve according to an embodiment.

FIG. 2 is a sectional view of a variable displacement compressor.

3A is a cross-sectional view of a capacity control valve according to another embodiment, and FIG. 3B is a cross-sectional view of a capacity control valve according to another embodiment.

FIG. 4 is a sectional view of a conventional electromagnetic actuator.

[Explanation of symbols]

11 front housing constituting the housing, 12
... Cylinder block, 13 ... Rear housing, 12a ... Cylinder bore, 15 ... Crank chamber, 16 ...
Drive shaft 23 23 Swash plate as cam plate 36 Piston 48 Control passage 49 Control valve 71 Electromagnetic actuator 73 Case 73 a Inside flange 7
4 ... Coil member, 75 ... Center post, 77 ... Sleeve, 77a ... Flange, 78 ... Plunger, 81 ... Valve chamber, 8
2 ... valve element, 83 ... pressure sensing part, 84 ... solenoid rod, 8
5: Valve hole, 91: Pressure-sensitive rod.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) H01F 7/16 F04B 27/08 S // H02K 33/02 H01F 7/16 RF term (reference) 3H045 AA04 AA10 AA13 AA27 BA19 BA28 CA01 CA02 CA03 DA25 EA33 3H076 AA06 BB32 BB38 CC12 CC20 CC41 CC84 CC85 CC91 3H106 DA05 DA23 DB02 DB12 DB23 DB32 DC09 DD03 EE22 EE34 GA01 GA13 KK23 5E048 AA08 AB01 AD03 AD04 BA01 5H633 BB07 GG07H02 JA04

Claims (4)

[Claims] A coil member is provided inside a cylindrical magnetic material case having an inner flange, a non-magnetic material cylindrical sleeve is provided inside the coil member, and a non-magnetic material sleeve is provided. In an electromagnetic actuator in which a center post and a plunger are disposed inside, the center post is disposed in contact with an inner peripheral surface of an inner flange of the case, and the sleeve has a flange portion bent outward at one end. Is fixed to the inner surface of the inner flange of the case. 2. A ratio of a cross-sectional area of a portion of the center post corresponding to the sleeve to a cross-sectional area of a portion of the case corresponding to an outer peripheral surface of the coil member is approximately 1: 1. Item 7. The electromagnetic actuator according to Item 1. 3. A valve comprising a valve element driven by the electromagnetic actuator according to claim 1. 4. A piston housed reciprocally in a cylinder bore formed in a housing, a crank chamber defined in the housing, and a crank chamber housed in the crank chamber for rotating the drive shaft by rotating the piston. A cam plate that is operatively connected to the piston to change the reciprocating motion and changes the stroke of the piston by changing the tilt angle, wherein the tilt angle of the cam plate is controlled by controlling the pressure in the crank chamber. A capacity control valve provided in a capacity compressor, comprising: a valve chamber communicated through a valve hole to a control passage to be adjusted in opening degree; and a valve body housed in the valve chamber and opening and closing the valve hole. A pressure-sensitive part connected to one side of the valve body via a pressure-sensitive rod, and for urging the valve body in a direction in which the opening of the valve hole changes according to the pressure of fluid; And a solenoid rod driven by a plunger of the electromagnetic actuator, the capacity of the variable displacement compressor using the electromagnetic actuator according to claim 1 or 2 as the electromagnetic actuator. Control valve.