JP4864657B2 - Clutchless variable capacity compressor - Google Patents

Description

  The present invention relates to a clutchless variable capacity compressor.

A housing, a discharge chamber, a suction chamber, a crank chamber, a plurality of cylinder bores formed in the housing, a piston inserted in the cylinder bore, a drive shaft disposed in the housing and rotatably supported by the housing; A conversion mechanism including a swash plate element having a variable tilt angle for converting the rotation of the shaft into a reciprocating movement of the piston, a capacity control valve disposed in an air supply passage between the discharge chamber and the crank chamber, and the crank chamber and the suction chamber And a throttle element disposed in the bleed passage between and the drive shaft is driven by an external drive source without a clutch, and the crank chamber pressure is adjusted by adjusting the opening of the capacity control valve. A clutchless variable displacement compressor in which the stroke is adjusted in the range from maximum to minimum and the discharge capacity is variably controlled, and the capacity control valve is a pressure sensitive capacity disposed in the first air supply passage. And valve, clutchless variable displacement compressor is disclosed in Patent Document 1 consists of electromagnetic valve and disposed in the second supply passage.
Japanese Patent Laid-Open No. 7-127469

The clutchless variable capacity compressor of Patent Document 1 has the following problems.
(1) Since two valves are mounted on the compressor, the compressor becomes larger and the compressor mounting space is expanded.
(2) Since the two valve accommodating portions and the two air supply passages are formed in the compressor, the structure of the compressor is complicated, and the productivity of the compressor is reduced.
(3) Since two valves are attached to the compressor, the assemblability of the compressor deteriorates.
The present invention has been made in view of the above problems, and an object of the present invention is to provide a clutchless variable capacity compressor that is downsized and excellent in productivity.

In order to solve the above problems, in the present invention, a housing, a discharge chamber, a suction chamber, a crank chamber, a plurality of cylinder bores formed in the housing, a piston inserted in the cylinder bore, and a piston are disposed in the housing. A drive shaft rotatably supported by the housing, a conversion mechanism including a variable swash plate element for converting the rotation of the drive shaft into a reciprocating motion of the piston, and an air supply passage between the discharge chamber and the crank chamber. And a throttle element disposed in a bleed passage between the crank chamber and the suction chamber. The drive shaft is rotationally driven by an external drive source without a clutch, and the capacity control valve A clutchless variable capacity compressor in which the crank chamber pressure is adjusted by adjusting the opening, the stroke of the piston is adjusted from the maximum to the minimum range, and the discharge capacity is variably controlled. The control valve includes a diaphragm that senses and displaces suction chamber pressure or crank chamber pressure, a pressure-sensitive unit having a housing made of a magnetic material that forms a vacuum sealed space in cooperation with the diaphragm, and a displacement of the diaphragm. In response, a valve mechanism that opens and closes the air supply passage, a first spring that biases the pressure-sensitive unit in the valve opening direction, a solenoid that has a fixed core and the pressure-sensitive unit as a movable core, and when the solenoid is excited And a first positioning member that positions the pressure-sensitive unit moved to the fixed core side at the first position.
In the clutchless variable displacement compressor according to the present invention, the pressure-sensitive capacity control valve and the electromagnetic on-off valve are integrated by causing the pressure-sensitive unit to function as a movable core of the solenoid, so the compressor is downsized. Compressor productivity is improved.

In a preferred aspect of the present invention, the clutchless variable displacement compressor has a second positioning member that positions the pressure-sensitive unit that has been moved in the valve opening direction by receiving the biasing force of the first spring when the solenoid is demagnetized. Is provided.
It is desirable to prevent unnecessary movement of the pressure sensitive unit during forced opening of the air supply passage.

In a preferred embodiment of the present invention, the housing of the pressure sensitive unit is a bottomed cylindrical body having one end opened, a diaphragm is joined to the open end of the housing to form a sealed space in the housing, and the diaphragm is opened in the valve opening direction. A second spring for biasing is disposed in the sealed space.
Since the pressure-sensitive unit having the above-described structure can have both a function as a pressure-sensitive mechanism of the pressure-sensitive capacity control valve and a function as a movable core of the electromagnetic on-off valve, by disposing the pressure-sensitive unit, The pressure sensitive capacity control valve and the electromagnetic on-off valve are integrated.

In a preferred embodiment of the present invention, the diaphragm is made of a non-magnetic stainless steel material, the housing of the pressure-sensitive unit is made of an electromagnetic stainless steel material, a flange is formed at the open end, and the diaphragm is entirely surrounded by the flange in a vacuum. Welded.
The diaphragm and the housing of the pressure-sensitive unit are formed of a stainless steel material, and a flange is formed at the open end of the housing, thereby facilitating welding between the diaphragm and the housing.

In a preferred aspect of the present invention, the pressure-sensitive unit includes an annular member made of a non-magnetic stainless steel material facing the flange of the housing, the diaphragm is sandwiched between the annular member and the flange, and the diaphragm, the annular member, and the flange Are welded all around in a vacuum and joined together.
By sandwiching the diaphragm between the annular member and the flange, the diaphragm can be welded to the flange while the peripheral edge of the diaphragm is in close contact with the flange, and the inside of the housing can be reliably maintained in a vacuum state.

In a preferred embodiment of the invention, the flange of the pressure sensitive unit housing forms part of the magnetic circuit.
By making the flange a part of the magnetic circuit, the facing area between the solenoid housing and the pressure-sensitive unit that also form the magnetic circuit can be increased, and the attractive force of the solenoid can be increased.

In a preferred aspect of the present invention, the first positioning member is made of a magnetic material, and when the solenoid is excited, the flange of the pressure-sensitive unit housing comes into contact with the first positioning member so that the pressure-sensitive unit is positioned at the first position. The communication path that connects the space where the end of the pressure-sensitive unit on the diaphragm side faces and the space where the end of the pressure-sensitive unit facing away from the diaphragm faces the flange of the housing of the pressure-sensitive unit and the first positioning It is formed in the contact portion with the member.
By using the first positioning member as a magnetic body and part of the magnetic circuit, the pressure-sensitive unit can be reliably brought into contact with the first positioning member. When the pressure-sensitive unit is positioned at the first position, the space where the end of the pressure-sensitive unit on the diaphragm side faces and the space where the end of the pressure-sensitive unit on the side away from the diaphragm communicates communicate with each other. Since no differential pressure is generated between both ends of the pressure unit, the pressure sensitive unit can be reliably moved by excitation and demagnetization of the solenoid.

In a preferred aspect of the present invention, when the solenoid is demagnetized, the annular member comes into contact with the second positioning member so that the pressure-sensitive unit is positioned at the second position, and the diaphragm-side end of the pressure-sensitive unit faces each other. A communication path that communicates with the space facing the end portion on the side separated from the diaphragm of the pressure-sensitive unit is formed in the contact portion between the annular member and the second positioning member.
When the pressure-sensitive unit is positioned at the second position, the space where the end of the pressure-sensitive unit facing the diaphragm and the space where the end of the pressure-sensitive unit facing away from the diaphragm face each other communicate with each other. Since no differential pressure is generated between both ends of the pressure unit, the pressure sensitive unit can be reliably moved by excitation and demagnetization of the solenoid.

In the clutchless variable displacement compressor according to the present invention, the pressure-sensitive capacity control valve and the electromagnetic on-off valve are integrated by causing the pressure-sensitive unit to function as a movable core of the solenoid, so the compressor is downsized. Compressor productivity is improved.

Examples of the present invention will be described.
As shown in FIG. 1, a variable capacity swash plate compressor 100 includes a cylinder block 101 having a plurality of cylinder bores 101a, a front housing 102 provided at one end of the cylinder block 101, and a cylinder block via a valve plate 103. And a rear housing 104 provided at the other end of 101.
A drive shaft 106 is disposed across the crank chamber 105 formed by the cylinder block 101 and the front housing 102. The drive shaft 106 is inserted through the swash plate 107. The swash plate 107 is coupled to a rotor 108 fixed to the drive shaft 106 via a connecting portion 109 and is supported by the drive shaft 106 so that the tilt angle is variable. A coil spring 110 is disposed between the rotor 108 and the swash plate 107 to urge the swash plate 107 toward the minimum inclination angle. On the opposite side of the coil spring 110 across the swash plate 107, a coil spring 111 for urging the swash plate 107 in the minimum tilt state in the direction of increasing the tilt angle is disposed.

One end of the drive shaft 106 passes through the boss portion 102a of the front housing 102 and extends to the outside of the housing, and is directly connected to a vehicle engine (not shown) via a power transmission device (not shown) without using an electromagnetic clutch. . Therefore, the variable displacement swash plate compressor 100 is a clutchless variable displacement compressor. A shaft seal device 112 is disposed between the drive shaft 106 and the boss portion 102a.
The drive shaft 106 is supported in the radial direction and the thrust direction by bearings 113, 114, 115, and 116.

A piston 117 is disposed in the cylinder bore 101a, and a pair of shoes 118 housed in a recess 117a at one end of the piston 117 sandwich the outer peripheral portion of the swash plate 107 so as to be slidable relative to each other. The rotation of the drive shaft 106 is converted into a reciprocating motion of the piston 117 via the swash plate 107 and the shoe 118.

A suction chamber 119 and a discharge chamber 120 are formed in the rear housing 104. The suction chamber 119 communicates with the cylinder bore 101a via a communication hole 103a formed in the valve plate 103 and a suction valve (not shown), and the discharge chamber 120 communicates with a discharge hole (not shown) and a communication hole 103b formed in the valve plate 103. Is communicated with the cylinder bore 101a. The suction chamber 119 is connected to an evaporator of a vehicle air conditioner (not shown) through a suction port 104a.
The front housing 102, the cylinder block 101, the valve plate 103, and the rear housing 104 cooperate to form a housing in which a discharge chamber 120, a suction chamber 119, a crank chamber 105, and a plurality of cylinder bores 101a are formed. .

A muffler 121 is disposed outside the cylinder block 101. The muffler 121 is formed by joining a bottomed cylindrical lid member 122 separate from the cylinder block 101 to a cylindrical wall 101b erected on the outer surface of the cylinder block 101 via a seal member. . A discharge port 122 a is formed in the lid member 122. The discharge port 122a is connected to a condenser of a vehicle air conditioner (not shown).
A communication passage 123 that allows the muffler 121 to communicate with the discharge chamber 120 is formed across the cylinder block 101, the valve plate 103, and the rear housing 104. The muffler 121 and the communication passage 123 form a discharge passage extending between the discharge chamber 120 and the discharge port 122a, and the muffler 121 forms an expansion space arranged in the middle of the discharge passage. Yes.
A check valve 200 that opens and closes the inlet of the muffler 121 is disposed in the muffler 121.

The front housing 102, the cylinder block 101, the valve plate 103, and the rear housing 104 are adjacent to each other via a gasket (not shown), and are integrally assembled using a plurality of through bolts 124.

A capacity control valve 300 is attached to the rear housing 104. The capacity control valve 300 is disposed in the air supply passage 125 between the discharge chamber 120 and the crank chamber 105 to adjust the opening of the passage and control the amount of refrigerant gas discharged into the crank chamber 105. To do. The refrigerant gas in the crank chamber 105 is sucked through a gap between the bearings 115 and 116 and the drive shaft 106, a space 126 formed in the cylinder block 101, and an orifice hole 103 c formed in the valve plate 103. Flows into chamber 119.

The configuration of the capacity control valve 300 will be described in detail.
As shown in FIGS. 2 and 3, the capacity control valve 300 includes a valve mechanism 310, a pressure sensitive unit 320, and a solenoid 330.

The valve mechanism 310 is slidably inserted into the valve housing 311, the valve housing 311, a transmission rod 312 that transmits a displacement of a diaphragm that will be described later to a valve body that will be described later, and a valve rod 311 a. In response to the displacement of 312, a valve body 313 that controls opening and closing of a valve hole 311 b disposed in the air supply passage 125, and a valve body 313 that is disposed in the valve chamber 311 a and biases the valve body 313 in the valve closing direction. And an adjustment screw 315 that is screwed into the valve housing 311 to adjust the urging force of the spring 314, and a filter 316 attached to the inlet of the valve chamber 311a. The valve chamber 311a communicates with the discharge chamber 120, and the valve hole 311b communicates with the crank chamber 105 via the communication hole 311c.

The pressure-sensitive unit 320 is disposed in a pressure-sensitive chamber 311d formed in the valve housing 311 and is a non-magnetic stainless steel that receives the pressure of the suction chamber 119 (hereinafter referred to as suction chamber pressure) via the communication hole 311e. A diaphragm 321 made of a base material, a pressure-sensitive housing 322 made of a bottomed cylindrical electromagnetic stainless steel material with a flange 322b formed at the open end, and a non-clamping peripheral edge of the diaphragm 321 in cooperation with the flange 322b An annular member 323 made of a magnetic stainless steel material and an urging force that is disposed in the pressure-sensitive housing 322 and that opposes the urging force that the suction chamber pressure applies to the diaphragm 321 are applied to the diaphragm 321 via the guide 324. And a spring 325 that performs. The peripheral edge of the diaphragm 321, the flange 322 b that sandwiches the peripheral edge, and the annular member 323 are integrally welded together in a vacuum. The diaphragm 321 forms a vacuum sealed space in the pressure sensitive housing 322 in cooperation with the pressure sensitive housing 322. The guide 324 is slidably fitted in the pressure sensitive housing 322. A step portion 322 c that restricts the movement of the guide 324 toward the bottom of the pressure-sensitive housing 322 is formed on the inner peripheral surface of the pressure-sensitive housing 322. When the guide 324 contacts the step 322c and the movement of the guide 324 is restricted, the displacement of the diaphragm 321 that has received the suction chamber pressure is restricted.

The solenoid 330 has a solenoid housing 331 made of a magnetic iron-based material and one end fixed to one end of the solenoid housing 331, and receives the cylindrical portion 322d of the pressure-sensitive housing 322 so that the cylindrical portion can slide. A sleeve 332 made of a nonmagnetic stainless steel material to be supported, and a fixed core 333 made of a magnetic iron material fixed to the other end of the sleeve 332 and facing the bottom 322e of the pressure sensitive housing 322 with a predetermined gap therebetween. A spring 334 that is disposed between the fixed core 333 and the bottom 322e of the pressure-sensitive housing 322 and biases the pressure-sensitive housing 320 in the valve opening direction, the other end of the solenoid housing 331, and the fixed core 333 A plate 335 made of a magnetic iron-based material, a fixed core 333, and a sleeve 332 are disposed between them. Wound is accommodated in the solenoid housing 331, and a coil member 336 which is molded with resin.
With the flange 322b of the pressure-sensitive housing 322 in contact with one end surface 331a of the solenoid housing 331, there is a gap between the bottom 322e of the pressure-sensitive housing and the fixed core 333.
The urging force of the spring 334 is set to be larger than the resultant force of the force generated by the differential pressure between the discharge pressure acting on the valve body 313 and the crank chamber pressure and the urging force of the spring 314.
A magnetic circuit is formed by the pressure-sensitive housing 322, the solenoid housing 331, the plate 335, and the fixed core 333. Accordingly, the pressure-sensitive housing 322 and thus the pressure-sensitive unit 320 function as a movable core of the solenoid 330.

When a vehicle power supply voltage is applied to the solenoid 330, an electromagnetic force is applied to the pressure-sensitive housing 322, the pressure-sensitive unit 320 moves toward the one end surface 331a of the solenoid housing 331 and the fixed core 333, and the flange 322b moves to the one side. The pressure sensitive unit 320 is positioned at the first position in contact with the end surface 331a.
When the flange 322b comes into contact with the one end surface 331a, the space where the end portion on the diaphragm 321 side of the pressure-sensitive unit 320 faces and the space where the end portion 322e on the side separated from the diaphragm 321 of the pressure-sensitive unit 320 face each other. Are formed on one end face 331a of the solenoid housing 331 and the outer peripheral surface of the cylindrical portion of the pressure-sensitive housing 322.

When the application of the voltage to the solenoid 330 is stopped, the electromagnetic force disappears, the pressure-sensitive unit 320 moves in the valve opening direction by the biasing force of the spring 334, and the annular member 323 comes into contact with the regulating portion 311f of the valve housing 311. Thus, the pressure sensitive unit 320 is positioned at the second position.
When the annular member 323 comes into contact with the restricting portion 311f, a space where the end portion on the diaphragm 321 side of the pressure sensitive unit 320 faces and a space where the end portion 322e on the side separated from the diaphragm 321 of the pressure sensitive unit 320 faces. A communication groove 311g is formed in the restricting portion 311f.

The discharge capacity control operation of the clutchless variable displacement swash plate compressor 100 will be described.
When operating the vehicle air conditioner, a vehicle power supply voltage is applied to the solenoid 330. As shown in FIG. 4A, the pressure sensitive unit 320 is positioned at the first position. The electromagnetic force of the solenoid 330 applied to the pressure-sensitive unit 320 is transmitted to the solenoid housing 331, and no electromagnetic force is applied to the diaphragm 321 made of a non-magnetic material. Therefore, the influence of the electromagnetic force is applied to the diaphragm 321 that is a pressure-sensitive member. Is not enough. Therefore, the capacity control valve 300 functions as a pressure-sensitive capacity control valve that autonomously controls the suction chamber pressure to a predetermined value.
When the suction chamber pressure is higher than a predetermined value, the diaphragm 321 is displaced to the right side in the figure, and the valve body 313 that receives the urging force of the spring 314 closes the valve hole 311b. Since the supply passage 125 is closed and blow-by gas is discharged from the extraction passage, the crank chamber pressure is reduced to be equal to the suction chamber pressure, and the discharge capacity is maximized.
When the compressor 100 is operated at the maximum discharge capacity and the suction chamber pressure is reduced to a predetermined value, the diaphragm 321 is displaced to the left side in the figure, and the valve body 313 pushed by the transmission rod 312 opens the valve hole 311b. The supply passage 125 is opened, and the refrigerant in the discharge chamber 120 flows into the crank chamber 105. Since the amount of the refrigerant gas flowing out from the crank chamber 105 to the suction chamber 119 is limited by the fixed orifice 103c, the crank chamber pressure rises, and the inclination angle of the swash plate 107 increases due to an increase in the pressure difference between the crank chamber 105 and the suction chamber 119. Decrease and discharge capacity decreases.
When the discharge capacity is decreased and the suction chamber pressure is increased, the diaphragm 321 is displaced to the right side in the drawing, and the valve body 313 that receives the urging force of the spring 314 moves in a direction to close the valve hole 311b. The amount of refrigerant in the discharge chamber 120 flowing into the crank chamber 105 decreases and the crank chamber pressure decreases, and the inclination of the swash plate 107 increases due to the decrease in the pressure difference between the crank chamber 105 and the suction chamber 119, thereby increasing the discharge capacity. To do. The above operation is repeated, and the discharge capacity is autonomously controlled so as to maintain the suction chamber pressure at a predetermined value.
The control characteristics of the clutchless variable displacement swash plate compressor 100 are shown in FIG.

When stopping the operation of the vehicle air conditioner, the application of the vehicle power supply voltage to the solenoid 330 is stopped. The capacity control valve 300 functions as an electromagnetic on-off valve. As shown in FIG. 4B, the pressure-sensitive unit 320 is positioned at the second position, and the transmission rod 312 pushed by the pressure-sensitive unit 320 pushes the valve body 313. Then, the valve hole 311b and thus the air supply passage 125 are forcibly opened. The refrigerant in the discharge chamber 120 always flows into the crank chamber 105, the crank chamber pressure rises, and the discharge capacity is kept to a minimum.

In the clutchless variable displacement compressor according to the present invention, the pressure sensitive unit 320 is made to function as the movable core of the solenoid 330, so that the pressure sensitive capacity control valve and the electromagnetic on-off valve are integrated. The productivity of the compressor is improved.
Since the regulation unit 311f that positions the pressure-sensitive unit 320 that has been moved in the valve opening direction by receiving the biasing force of the spring 334 when the solenoid 330 is demagnetized is provided, the pressure-sensitive unit 1251 is pressure-sensitive during the forced opening of the air supply passage 125. Unnecessary movement of the unit 320 is prevented, and unnecessary movement of the valve body 313 is prevented, and the operation of the capacity control valve 300 is stabilized.
A pressure-sensitive housing 322 having a bottomed cylindrical body with one end open is provided, and a diaphragm 321 is joined to the open end of the pressure-sensitive housing 322 to form a sealed space in the pressure-sensitive housing 322, and the diaphragm 321 is opened. A pressure-sensitive unit 320 having a configuration in which a spring 325 biased in the direction is disposed in the sealed space has a function as a pressure-sensitive mechanism of a pressure-sensitive capacity control valve and a function as a movable core of an electromagnetic on-off valve. Since the pressure sensitive unit 320 is provided, the pressure sensitive capacity control valve and the electromagnetic on-off valve are integrated.
By forming the diaphragm 321 and the pressure-sensitive housing 322 from a stainless steel material and forming the flange 322b at the open end of the pressure-sensitive housing 322, the diaphragm 321 and the pressure-sensitive housing 322 can be easily welded.
By sandwiching the diaphragm 321 between the annular member 323 and the flange 322b, the periphery of the diaphragm 321 can be welded to the flange 322b in a state of being in close contact with the flange 322b, and the inside of the pressure-sensitive housing 322 is reliably vacuumed. Can be maintained.
By making the flange 322b a part of the magnetic circuit, it is possible to increase the attractive force of the solenoid 330 by increasing the facing area between the solenoid housing 331 and the pressure-sensitive unit 320 that also form the magnetic circuit.
By using the end surface 331a of the solenoid housing 331 that is a part of the magnetic circuit as a member for positioning the pressure-sensitive unit 320 in the first position, the pressure-sensitive unit 320 can be reliably brought into contact with the positioning member 331a. When the pressure-sensitive unit 320 is positioned at the first position, a space where the end of the pressure-sensitive unit 320 on the diaphragm side faces and a space where the end 322e on the side away from the diaphragm of the pressure-sensitive unit 320 faces each other. The pressure-sensitive unit 320 communicates via the communication grooves 331b and 322g, and no differential pressure is generated between both ends of the pressure-sensitive unit 320. Therefore, the pressure-sensitive unit 320 can be reliably moved by excitation and demagnetization of the solenoid 330.
When the pressure-sensitive unit 320 is positioned at the second position, a space where the end of the pressure-sensitive unit 320 on the diaphragm side faces and a space where the end 322e on the side away from the diaphragm of the pressure-sensitive unit 320 faces. Since the pressure is communicated through the communication groove 311g and no differential pressure is generated between both ends of the pressure-sensitive unit 320, the pressure-sensitive unit can be reliably moved by the excitation and demagnetization of the solenoid 330.

The sleeve 332 may be formed of a magnetic material.
As shown in FIG. 6, the transmission rod 312 and the valve body 313 may be integrally formed, the communication hole 311c may be communicated with the discharge chamber, and the valve chamber 311a may be communicated with the crank chamber.
Instead of communicating the pressure sensitive chamber 311d with the suction chamber 119, the pressure sensitive chamber 311d may be communicated with the crank chamber 105. In this case, the discharge capacity is controlled so that the crank chamber pressure is maintained at a predetermined value.
The pressure sensitive housing 322 may be formed of a magnetic material other than an electromagnetic stainless steel such as iron.
The diaphragm 321 may be formed of a nonmagnetic material other than stainless steel.
The pressure-sensitive housing 322 may have a structure without the flange 322b.
A spring 334 may be provided to urge the flange 322b.
The present invention may be applied to a capacity control valve that controls the suction chamber pressure to a predetermined value without being affected by the discharge pressure, and a capacity control valve that increases the control suction chamber pressure when the discharge chamber pressure increases.
The present invention may be applied to a swing plate type variable displacement compressor.
The present invention may be applied to a motor-driven variable capacity compressor.
The throttle disposed in the extraction passage may be a variable flow rate throttle.
The present invention may be applied to a variable capacity compressor using CO2 or R152a as a refrigerant instead of the current R134a.

1 is a cross-sectional view of a clutchless variable displacement swash plate compressor according to an embodiment of the present invention. It is sectional drawing of the capacity | capacitance control valve with which the clutchless variable capacity | capacitance swash plate type compressor which concerns on the Example of this invention is provided. FIG. 3 is a partially enlarged view of FIG. 2. It is a fragmentary sectional view of the capacity control valve with which the clutchless variable capacity swash plate type compressor concerning the example of the present invention is provided. (A) is sectional drawing at the time of solenoid excitation, (b) is sectional drawing at the time of solenoid demagnetization. It is a figure which shows the control characteristic formula of the capacity | capacitance control valve with which the clutchless variable capacity | capacitance swash plate type compressor which concerns on the Example of this invention is provided. It is a fragmentary sectional view of the modification of a capacity control valve.

Explanation of symbols

100 Clutchless variable displacement swash plate compressor 105 Crank chamber 119 Suction chamber 120 Discharge chamber 125 Air supply passage 300 Capacity control valve 310 Valve mechanism 320 Pressure sensitive unit 321 Diaphragm 322 Pressure sensitive housing 330 Solenoid

Claims (8)

A housing, a discharge chamber, a suction chamber, a crank chamber, a plurality of cylinder bores formed in the housing, a piston inserted in the cylinder bore, a drive shaft disposed in the housing and rotatably supported by the housing; A conversion mechanism including a swash plate element having a variable tilt angle for converting the rotation of the shaft into a reciprocating movement of the piston, a capacity control valve disposed in an air supply passage between the discharge chamber and the crank chamber, and the crank chamber and the suction chamber And a throttle element disposed in the bleed passage between and the drive shaft is driven by an external drive source without a clutch, and the crank chamber pressure is adjusted by adjusting the opening of the capacity control valve. A clutchless variable displacement compressor in which the stroke is adjusted from the maximum to the minimum and the discharge capacity is variably controlled. The displacement control valve senses the suction chamber pressure or the crank chamber pressure. A pressure-sensitive unit having a diaphragm that is displaced, a housing made of a magnetic material that forms a vacuum sealed space in cooperation with the diaphragm, a valve mechanism that opens and closes an air supply passage in response to the displacement of the diaphragm, A first spring for urging the pressure-sensitive unit in the valve opening direction, a solenoid having a fixed core and having the pressure-sensitive unit as a movable core, and a pressure-sensitive unit that has moved toward the fixed core when the solenoid is excited are A clutchless variable capacity compressor, comprising: a first positioning member for positioning at a position. 2. The clutchless variable according to claim 1, further comprising a second positioning member that positions, in a second position, the pressure-sensitive unit that has moved in the valve opening direction by receiving the biasing force of the first spring when the solenoid is demagnetized. 3. Capacity compressor. The housing of the pressure-sensitive unit is a bottomed cylinder whose one end is open, a diaphragm is joined to the open end of the housing to form a sealed space in the housing, and a second spring for biasing the diaphragm in the valve opening direction is provided. The clutchless variable capacity compressor according to claim 1 or 2, wherein the clutchless variable capacity compressor is disposed in the sealed space. The diaphragm is made of a non-magnetic stainless steel material, the housing of the pressure-sensitive unit is made of an electromagnetic stainless steel material, a flange is formed at the open end, and the diaphragm is welded to the flange all around the vacuum. The clutchless variable capacity compressor according to claim 3. The pressure-sensitive unit includes an annular member made of a non-magnetic stainless steel material facing the flange of the housing. The diaphragm is sandwiched between the annular member and the flange, and the diaphragm, the annular member, and the flange are welded all around in vacuum. The clutchless variable capacity compressor according to claim 4, wherein the clutchless variable capacity compressor is integrally joined. 6. The clutchless variable capacity compressor according to claim 4, wherein the flange of the pressure-sensitive unit housing forms part of a magnetic circuit. The first positioning member is made of a magnetic material, and when the solenoid is excited, the flange of the housing of the pressure sensitive unit comes into contact with the first positioning member so that the pressure sensitive unit is positioned at the first position. A communication path is formed in the contact portion between the flange of the pressure-sensitive unit housing and the first positioning member to communicate the space where the end faces and the space where the end on the side separated from the diaphragm of the pressure-sensitive unit faces. The clutchless variable capacity compressor according to claim 6, wherein the compressor is a variable capacity compressor. When the solenoid is demagnetized, the annular member comes into contact with the second positioning member and the pressure-sensitive unit is positioned at the second position, and the space facing the diaphragm-side end of the pressure-sensitive unit is separated from the diaphragm of the pressure-sensitive unit. The clutch according to any one of claims 5 to 7, wherein a communication passage that communicates with a space facing an end portion on the side to be engaged is formed in a contact portion between the annular member and the second positioning member. Less variable capacity compressor.

Images