JP2009275550A - Capacity control valve of variable displacement compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress, by a simple constitution, the influence of a temperature change in the coil of a solenoid-operated capacity control valve whose electromagnetic driving force is controlled by applying a voltage on the coil of a solenoid. <P>SOLUTION: The solenoid-operated capacity control valve 35 adjusts the sectional area of a supply passage 33 tying a discharge chamber 132 to a control pressure chamber 121. A voltage is applied to the coil 38 of the solenoid 36 of the solenoid-operated capacity control valve 35. Between a fixed iron-core 37 and a movable iron-core 39 constituting the solenoid 36, a thermo-sensitive member 54 is installed, which is made of a shape memory alloy and restricts the forefront limit position in the advancing direction of a valve element 401 in association with an increase of the applied voltage (increase in the electromagnetic driving force), and the member 54 retreats the forefront limit position in the middle of the temperature lowering and advances it in the middle of the temperature rising. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention supplies the refrigerant in the discharge pressure region to the control pressure chamber, discharges the refrigerant in the control pressure chamber to the suction pressure region, regulates the pressure in the control pressure chamber, and adjusts the pressure in the control pressure chamber. The present invention relates to a capacity control valve in a variable capacity compressor that controls a discharge capacity.

  In a variable capacity compressor having a control pressure chamber that accommodates a swash plate with a variable tilt angle, the tilt angle of the swash plate decreases as the pressure in the control pressure chamber increases, and the tilt angle of the swash plate decreases as the pressure in the control pressure chamber decreases. Becomes larger. When the inclination angle of the swash plate decreases, the stroke of the piston decreases and the discharge capacity decreases. When the inclination angle of the swash plate increases, the stroke of the piston increases and the discharge capacity increases.

  The pressure in the control pressure chamber is adjusted by controlling the valve opening degree of the electromagnetic capacity control valve. In the configuration in which the electromagnetic capacity control valve is interposed on the supply passage, the refrigerant flowing from the discharge pressure region to the control pressure chamber increases as the valve opening increases, and the pressure in the control pressure chamber increases. In the configuration in which the electromagnetic capacity control valve is interposed on the discharge passage, the refrigerant flowing out from the control pressure chamber to the suction pressure region decreases as the valve opening decreases, and the pressure in the control pressure chamber increases.

  The valve opening degree of the electromagnetic capacity control valve depends on the value of the current flowing through the solenoid coil. The resistance of the solenoid coil decreases as the coil temperature decreases and increases as the coil temperature increases. Therefore, in a circuit configuration that generates an electromagnetic driving force by applying a voltage to the solenoid, if the resistance of the coil is affected by the temperature and is too small than the original value, the voltage corresponding to the desired valve opening Is applied to the coil, the value of the current flowing through the coil becomes larger than the original value. On the other hand, if the resistance of the coil is too large due to the temperature, the value of the current flowing through the coil is the original value even if a voltage corresponding to the desired valve opening is applied to the coil. It will be smaller than the value.

In such a situation, there is a possibility that the opening degree of the valve may be larger than the original, and the discharge capacity may be greatly different from the target discharge capacity.
Patent Document 1 discloses a control valve drive circuit that is not affected by coil temperature changes.
JP 2004-152938 A

However, the countermeasure for eliminating the influence of the coil temperature change by the circuit configuration makes the circuit complicated and disadvantageous in terms of cost.
It is an object of the present invention to suppress the influence of a temperature change of a coil in an electromagnetic capacity control valve in which an electromagnetic driving force is controlled by applying a voltage to a solenoid coil with a simple configuration. Objective.

  According to the present invention, the refrigerant in the discharge pressure region is supplied to the control pressure chamber through the supply passage, and the refrigerant in the control pressure chamber is discharged to the suction pressure region through the discharge passage to adjust the pressure in the control pressure chamber. A discharge capacity is controlled by regulating the pressure in the control pressure chamber, and an electromagnetic capacity control valve for adjusting a cross-sectional area of the supply passage or the discharge passage is provided. The electromagnetic driving force applied to the valve body is intended for a capacity control valve in a variable capacity compressor controlled by voltage application control of voltage changing means for applying a voltage to a solenoid coil of the electromagnetic capacity control valve. In the invention of Item 1, a temperature sensitive member for restricting a movable range of the valve body is provided, and the temperature sensitive member restricts a foremost limit position in a traveling direction of the valve body as the electromagnetic driving force increases. And said Restrict the dynamic range, the temperature sensitive member, retracting the frontmost limit position in the course of temperature becomes lower, thereby advancing the frontmost limit position in the course of temperature increases.

  When the resistance of the coil is affected by the temperature and is too smaller than the original value corresponding to the applied voltage, the temperature sensitive member moves the front limit position backward. Therefore, even if the value of the current flowing through the coil becomes larger than the original value, the position of the valve body does not deviate more than the target position. On the other hand, when the resistance of the coil is too large than the original value corresponding to the applied voltage due to the influence of the temperature, the temperature sensitive member advances the forefront limit position. Therefore, even if the value of the current flowing through the coil becomes too smaller than the original value, the position of the valve body does not deviate more than the target position. The configuration in which the forefront limit position is changed by the temperature sensitive member is a simple configuration for suppressing the influence of the temperature change of the coil.

  In a preferred example, the temperature sensitive member is provided on the traveling side of the valve body as the voltage increases, or on the traveling side of an accessory member that moves integrally with the valve body. The length of the temperature sensitive member in the direction is shortened in the middle of the temperature increasing to advance the foremost limit position, and the length of the temperature sensitive member is lengthened in the middle of the temperature decreasing to be the foremost limit Move the position backward.

The structure in which the temperature sensitive member is expanded and contracted in the movable direction of the valve body is a simple structure in changing the foremost limit position.
In a preferred example, the temperature sensitive member is provided between a fixed iron core and a movable iron core of the solenoid.

The interval between the fixed iron core and the movable iron core is directly reflected in the valve opening. Between such a fixed iron core and a movable iron core, it is suitable as an arrangement place of a temperature sensitive member.
In a preferred example, the valve body is provided on a transmission rod fixed to the movable iron core, and the temperature sensitive member is a ring inserted through the transmission rod.

The ring is suitable as a shape of the temperature sensitive member that deforms.
In a preferred example, the temperature sensitive member is a shape memory member.
The shape memory member is suitable for accurately identifying the length change of the temperature sensitive member due to the shape change accompanying the temperature change.

  INDUSTRIAL APPLICABILITY The present invention has an excellent effect that the influence of the temperature change of the coil in the electromagnetic capacity control valve in which the electromagnetic driving force is controlled by applying a voltage to the solenoid coil can be suppressed with a simple configuration. Play.

A first embodiment in which the present invention is embodied in a clutchless variable displacement compressor will be described below with reference to FIGS.
As shown in FIG. 1A, a front housing 12 is connected to the front end of the cylinder block 11. A rear housing 13 is connected to the rear end of the cylinder block 11 via a valve plate 14, valve forming plates 15 and 16, and a retainer forming plate 17. The cylinder block 11, the front housing 12, and the rear housing 13 constitute an overall housing of the clutchless variable displacement compressor 10.

  A rotary shaft 18 is rotatably supported via radial bearings 19 and 20 on the front housing 12 and the cylinder block 11 forming the control pressure chamber 121. The rotating shaft 18 that protrudes outside from the control pressure chamber 121 obtains driving force from an external drive source E (for example, a vehicle engine) via a pulley (not shown) and a belt (not shown).

  A rotary support 21 is fixed to the rotary shaft 18. A swash plate 22 is supported on the rotary shaft 18 so as to face the rotation support 21. The swash plate 22 is supported so as to be slidable and tiltable in the axial direction of the rotary shaft 18.

  A guide pin 23 provided on the swash plate 22 is slidably fitted in a guide hole 211 formed in the rotary support 21. The swash plate 22 can be tilted in the axial direction of the rotary shaft 18 by the linkage of the guide hole 211 and the guide pin 23 and can rotate integrally with the rotary shaft 18. The tilt of the swash plate 22 is guided by the slide guide relationship between the guide hole 211 and the guide pin 23 and the slide support action of the rotary shaft 18.

  If the diameter center part of the swash plate 22 moves to the rotation support body 21 side, the inclination angle of the swash plate 22 increases. The maximum inclination angle of the swash plate 22 is regulated by the contact between the rotary support 21 and the swash plate 22. The swash plate 22 shown by a solid line in FIG. 1 is in a minimum tilt state, and the swash plate 22 shown by a chain line is in a maximum tilt state. The minimum inclination angle of the swash plate 22 is slightly larger than 0 °.

  Pistons 24 are accommodated in a plurality of cylinder bores 111 penetrating the cylinder block 11. The rotational movement of the swash plate 22 is converted into the back-and-forth reciprocating movement of the piston 24 via the shoe 25, and the piston 24 reciprocates in the cylinder bore 111.

  A suction chamber 131 that is a suction pressure region and a discharge chamber 132 that is a discharge pressure region are defined in the rear housing 13. A suction port 26 is formed in the valve plate 14, the valve forming plate 16, and the retainer forming plate 17, and a discharge port 27 is formed in the valve plate 14 and the valve forming plate 15. A suction valve 151 is formed on the valve forming plate 15, and a discharge valve 161 is formed on the valve forming plate 16.

  The refrigerant in the suction chamber 131 flows into the compression chamber 112 from the suction port 26 by retreating the piston 24 (moving from the right side to the left side in FIG. 1). The refrigerant flowing into the compression chamber 112 is discharged into the discharge chamber 132 by pushing the discharge valve 161 away from the discharge port 27 by the forward movement of the piston 24 (movement from the left side to the right side in FIG. 1). The discharge valve 161 abuts on the retainer 171 on the retainer forming plate 17 and the opening degree is regulated.

When the pressure in the control pressure chamber 121 decreases, the tilt angle of the swash plate 22 increases and the discharge capacity increases. When the pressure in the control pressure chamber 121 increases, the tilt angle of the swash plate 22 decreases and the discharge capacity decreases.
The control pressure chamber 121 and the suction chamber 131 are communicated with each other via the discharge passage 34. The refrigerant in the control pressure chamber 121 flows out to the suction chamber 131 through the discharge passage 34.

  The suction chamber 131 and the discharge chamber 132 are connected by an external refrigerant circuit 28. On the external refrigerant circuit 28, a heat exchanger 29 for removing heat from the refrigerant, an expansion valve 30, and a heat exchanger 31 for transferring ambient heat to the refrigerant are interposed. The expansion valve 30 is a temperature type automatic expansion valve that controls the flow rate of the refrigerant according to the change in the gas temperature on the outlet side of the heat exchanger 31. A check valve 32 is provided on the way from the discharge chamber 132 to the external refrigerant circuit 28. When the check valve 32 is open, the refrigerant in the discharge chamber 132 flows out to the external refrigerant circuit 28 and returns to the suction chamber 131.

A throttle 281 is provided in the middle of an external refrigerant circuit (hereinafter referred to as external refrigerant circuit 28A) downstream of the check valve 32 and upstream of the heat exchanger 29.
An electromagnetic capacity control valve 35 is assembled to the rear housing 13.

  As shown in FIG. 1B, a voltage application circuit 50 is electrically connected to the coil 38 constituting the solenoid 36 of the electromagnetic capacity control valve 35. The voltage application circuit 50 applies a voltage to the coil 38.

  The fixed iron core 37 constituting the solenoid 36 of the electromagnetic capacity control valve 35 attracts the movable iron core 39 based on excitation by applying a voltage to the coil 38. A transmission rod 40 is fixed to the movable iron core 39. The transmission rod 40 passes through the fixed iron core 37 and protrudes into the valve housing chamber 411 in the valve housing 41, and the valve body 401 is integrally formed with the transmission rod 40 in the valve housing chamber 411. The valve body 401 contacts and separates from the valve seat 42 to open and close the valve hole 351. When the valve body 401 is in the open position separated from the valve seat 42, the discharge chamber 132 and the control pressure chamber 121 communicate with each other via the passage 331, the valve storage chamber 411, the valve hole 351, and the passage 332. When the valve body 401 is in the closed position in contact with the valve seat 42, the communication between the discharge chamber 132 and the control pressure chamber 121 is blocked.

  The passage 331, the valve storage chamber 411, the valve hole 351, and the passage 332 constitute a supply passage 33 that supplies the refrigerant in the discharge chamber 132 to the control pressure chamber 121. The electromagnetic capacity control valve 35 adjusts the passage sectional area of the supply passage 33.

  A ring-shaped spring receiver 43 is fixed to the transmission rod 40 in the valve housing chamber 411, and a coil-shaped biasing spring 44 is interposed between the spring receiver 43 and the valve seat 42. The biasing spring 44 biases the transmission rod 40 in a direction away from the valve body 401 from the closed position in contact with the valve seat 42. The electromagnetic force of the solenoid 36 urges the valve body 401 toward the closed position against the spring force of the urging spring 44.

  A pressure sensing body 47 that divides the pressure sensing chambers 45 and 46 in the electromagnetic capacity control valve 35 is urged from the pressure sensing chamber 45 side to the pressure sensing chamber 46 side by a pressure sensing spring 48. The pressure sensitive chamber 45 is in communication with the discharge chamber 132, and the pressure sensitive chamber 46 is in communication with the external refrigerant circuit 28 </ b> A downstream of the throttle 281. That is, the pressure sensitive chamber 45 has a pressure in the discharge chamber 132, and the pressure sensitive chamber 46 has a pressure in the external refrigerant circuit 28 </ b> A downstream from the throttle 281 and upstream from the heat exchanger 29. ing. The pressure in the pressure sensitive chamber 45 and the pressure in the pressure sensitive chamber 46 are opposed to each other through the pressure sensitive body 47.

  The pressure-sensitive chambers 45 and 46, the pressure-sensitive body 47, and the pressure-sensitive spring 48 are differential pressures between the pressure in the discharge chamber 132 and the pressure in the external refrigerant circuit 28 downstream from the throttle 281 and upstream from the heat exchanger 31. The pressure-sensitive means 49 is configured to respond to the above. When the refrigerant flow rate in the external refrigerant circuit 28A (discharge pressure region) increases, the pressure difference before and after the throttle 281 increases, and when the refrigerant flow rate in the external refrigerant circuit 28 (discharge pressure region) decreases, the pressure before and after the throttle 281 increases. The difference between is reduced. The pressure sensing means 49 moves the valve body 401 away from the valve seat 42 by increasing the pressure difference before and after the throttle 281, and moves the valve body 401 to the valve seat 42 by decreasing the pressure difference before and after the throttle 281. Move closer. That is, the pressure sensing means 49 increases the valve opening according to the increase in the refrigerant flow rate in the discharge pressure region (external refrigerant circuit 28A), and the valve according to the decrease in the refrigerant flow rate in the discharge pressure region (external refrigerant circuit 28A). Decrease the opening.

  A transmission rod 40 is connected to the pressure sensitive body 47. The pressure in the pressure-sensitive chamber 45 and the spring force of the pressure-sensitive spring 48 urge the valve body 401 in a direction away from the closed position where the valve body 401 contacts the valve seat 42.

  The degree of opening and closing of the valve hole 351, that is, the valve opening degree of the electromagnetic capacity control valve 35 is determined by the balance of the electromagnetic force generated by the solenoid 36, the spring force of the biasing spring 44, and the biasing force of the pressure sensing means 49. The electromagnetic capacity control valve 35 can continuously adjust the interval (valve opening) between the valve body 401 and the valve seat 42 by changing the electromagnetic force (changing the duty ratio). That is, the electromagnetic capacity control valve 35 can continuously adjust the passage cross-sectional area of the supply passage 33 by changing the electromagnetic force, and increases the valve opening when the refrigerant flow rate in the discharge pressure region increases, thereby increasing the discharge pressure region. This is an electromagnetic capacity control valve that reduces the valve opening when the refrigerant flow rate in the engine decreases.

  As shown in FIGS. 1A and 1B, a control computer C is signal-connected to the voltage application circuit 50. The control computer C has an air conditioner operation switch 51, a room temperature setting device 52, and a room temperature detector 53. Is signal connected. The control computer C commands the voltage application circuit 50 to apply a voltage when the air conditioner operation switch 51 is turned on, and the voltage application circuit 50 applies a voltage to the coil 38 in response to this command. The control computer C commands the voltage application circuit 50 to stop voltage application by turning off the air conditioner operation switch 51, and the voltage application circuit 50 stops voltage application in response to this command. When the air conditioner operation switch 51 is in the ON state, the control computer C controls the coil 38 based on the temperature difference between the target room temperature set by the room temperature setter 52 and the detected room temperature detected by the room temperature detector 53. Controls voltage application.

  The voltage application circuit 50, the air conditioner operation switch 51, the room temperature setting device 52, the room temperature detector 53, and the control computer C constitute voltage changing means for applying a voltage to the coil 38 of the solenoid 36 in the electromagnetic capacity control valve 35.

  FIG. 3 shows a state in which voltage application to the coil 38 of the solenoid 36 is stopped by turning off the air conditioner operation switch 51 (the duty ratio is 0), and the valve opening degree of the electromagnetic capacity control valve 35 is maximized. ing. The minimum inclination angle of the swash plate 22 is slightly larger than 0 °, and the discharge from the cylinder bore 111 to the discharge chamber 132 is performed even when the inclination angle of the swash plate 22 is the minimum inclination angle. In the state where the inclination angle of the swash plate 22 is minimum, the check valve 32 is closed and the refrigerant circulation in the external refrigerant circuit 28 is stopped. The refrigerant discharged from the cylinder bore 111 into the discharge chamber 132 flows into the control pressure chamber 121 via the supply passage 33.

  In the state of FIG. 3, the inclination of the swash plate 22 becomes the minimum inclination, and the variable displacement compressor 10 performs the minimum capacity operation at which the discharge capacity is minimized, but the refrigerant does not circulate through the external refrigerant circuit 28. .

  FIG. 4 shows a state where the air conditioner operation switch 51 is ON and the applied voltage to the coil 38 of the solenoid 36 is maximum (duty ratio is 1). The valve opening degree of the electromagnetic capacity control valve 35 is as follows. It is zero. In a state where the variable displacement compressor 10 is operating at a non-minimum capacity (that is, a state where the inclination angle of the swash plate 22 is not minimum), the check valve 32 is opened and refrigerant circulation in the external refrigerant circuit 28 is performed. .

  When the valve opening degree of the electromagnetic capacity control valve 35 is zero (the valve hole 351 is closed), the supply passage 33 is closed, and the refrigerant in the discharge chamber 132 passes through the supply passage 33 to control pressure. It is not sent to the chamber 121. Further, the refrigerant in the control pressure chamber 121 flows out to the suction chamber 131 via the discharge passage 34. In this state, the inclination angle of the swash plate 22 becomes the maximum inclination angle, and the variable displacement compressor 10 performs the maximum capacity operation at which the discharge capacity becomes maximum.

  In a state where the air conditioner operation switch 51 is ON and the applied voltage to the coil 38 of the solenoid 36 is not zero and not maximum (duty ratio is larger than 0 and smaller than 1), the inclination angle of the swash plate 22 is the diaphragm 281. Therefore, the variable displacement compressor 10 performs an intermediate capacity operation in which the inclination angle of the swash plate 22 is equal to or greater than the minimum inclination angle so that the differential pressure before and after becomes a set differential pressure corresponding to the duty ratio.

  As shown in FIG. 2, an annular recess 391 is formed at the tip of the movable iron core 39 so as to surround the transmission rod 40, and a temperature sensitive member 54 made of a shape memory alloy is disposed in the recess 391. . The temperature sensitive member 54 includes a pair of rings 541 and 542 having the same shape and size. The temperature sensitive member 54 is provided on the traveling side of the movable iron core 39 (the traveling side of the valve body 401) as the voltage increases. The movable iron core 39 is an attachment member that moves integrally with the valve body 401.

  The temperature sensitive member 54 shown in FIG. 2 is in a martensitic phase. The rings 541 and 542 in the martensite phase have a disc spring shape, and the disc spring-shaped rings 541 and 542 face each other symmetrically. The situation where the temperature sensitive member 54 is in the martensitic phase is the situation where the electromagnetic capacity control valve 35 is below the martensitic transformation temperature.

  The temperature sensitive member 54 shown in FIG. 3 is in an austenite phase state. The rings 541 and 542 in the austenite phase state have a flat plate shape. The situation where the temperature sensitive member 54 is in the austenite phase state corresponds to the temperature rise of the electromagnetic capacity control valve 35 accompanying the operation of the variable capacity compressor 10.

  The temperature sensitive member 54 is provided on the traveling side of the movable iron core 39 as the applied voltage to the coil 38 increases (increase in electromagnetic driving force). The lengths L1 and L2 (shown in FIGS. 2 and 3) of the temperature sensitive member 54 in the movable direction of the valve body 401 (the direction indicated by the arrow R in FIG. 2) are on the way of increasing the temperature (passing the martensitic transformation temperature). When the temperature is lowered (when passing the martensitic transformation temperature).

  Immediately after the start of the operation of the variable capacity compressor 10 having the same temperature as the normal temperature, the temperature of the variable capacity compressor 10 is low, and after a certain amount of time has elapsed from the start of the operation of the variable capacity compressor 10, the variable capacity compressor 10 Temperature rises. The martensitic transformation temperature in the temperature sensitive member 54 is in the middle of a temperature change from the normal temperature state to the high temperature of the variable capacity compressor 10.

  When the length of the temperature sensitive member 54 becomes short [length L2], the foremost limit position S1 of the movable core 39 in the traveling direction of the movable core 39 accompanying the increase in applied voltage (increase in electromagnetic driving force) [see FIG. Is a position where the movable iron core 39 contacts the fixed iron core 37.

  When the length of the temperature sensitive member 54 becomes longer [length L1], the foremost limit position S2 of the movable core 39 in the traveling direction of the movable core 39 accompanying the increase in applied voltage (increase in electromagnetic driving force) [see FIG. In the figure, the movable iron core 39 is positioned away from the fixed iron core 37.

  The temperature sensitive member 54 provided on the traveling side of the movable iron core 39 (the traveling side of the valve body 401) accompanying the increase in voltage is shortened in the middle of the temperature rise and advances the foremost limit position from the foremost limit position S2. . Moreover, the temperature sensitive member 54 becomes longer in the middle of the temperature rise and makes the foremost limit position retract from the foremost limit position S1. The temperature-sensitive member 54 regulates the movable range of the valve body 401 by regulating the foremost limit position in the traveling direction of the valve body 401 accompanying the increase in applied voltage (increase in electromagnetic driving force).

In the first embodiment, the following effects can be obtained.
(1) The resistance of the coil 38 of the solenoid 36 changes under the influence of the temperature change. When the temperature rises, the resistance of the coil 38 increases, and when the temperature decreases, the resistance of the coil 38 decreases. When the temperature rise changes to pass the martensitic transformation temperature, the temperature sensitive member 54 advances the foremost limit position, and when the temperature fall changes to pass the martensitic transformation temperature, the temperature sensitive member 54 Move the limit position backward. Therefore, even if the value of the current flowing through the coil 38 changes, the position of the valve body 401 does not deviate more than the target position. The configuration in which the forefront limit position is changed by the temperature sensitive member 54 is a simple configuration for suppressing the influence of the temperature change of the coil 38.

  (2) When the temperature change changes so as to pass the martensitic transformation temperature, the temperature sensitive member 54 expands and contracts in the movable direction R of the valve body 401. The structure in which the temperature sensitive member 54 is expanded and contracted in the movable direction R of the valve body 401 is a simple structure in changing the foremost limit position.

  (3) The interval between the fixed iron core 37 and the movable iron core 39 is directly reflected in the valve opening. The temperature sensitive member 54 disposed between the fixed iron core 37 and the movable iron core 39 expands and contracts in the movable direction R of the movable iron core 39 and restricts the movable range of the movable iron core 39. If the lengths L1 and L2 of the temperature sensitive member 54 that expands and contracts in the moving direction R of the movable iron core 39 between the fixed iron core 37 and the movable iron core 39 are appropriately set, the movable range of the movable iron core 39 (that is, the foremost limit position). Is appropriately regulated in response to temperature changes that change to pass the martensitic transformation temperature. That is, the space between the fixed iron core 37 and the movable iron core 39 is suitable as an arrangement place of the temperature sensitive member 54.

  (4) The shape of the pair of rings 541 and 542 constituting the temperature sensitive member 54 is a shape in which a flat ring is forcibly deformed by applying a load so that it becomes a disc spring shape below the martensite transformation temperature. It is. It is easy to deform a flat ring into a disc spring shape, and the dimensional accuracy is high. Rings 541 and 542 obtained by deforming flat plate-shaped rings into a disc spring shape are suitable as the shape of the temperature sensitive member deformed by temperature change.

  (5) The shape memory alloy which is the material of the temperature sensitive member 54 can be deformed by press working, and the deformation by press working brings high processing accuracy. That is, the shape memory alloy that is the material of the temperature sensitive member 54 is a suitable material for accurately identifying the changes in the lengths L1 and L2 due to the shape change accompanying the temperature change.

Next, a second embodiment shown in FIGS. 6A and 6B will be described. The same reference numerals are used for the same components as those in the first embodiment, and detailed description thereof is omitted.
The urging spring 44 is provided between the fixed iron core 37 and the movable iron core 39, and a ring-shaped temperature sensitive member 55 is sandwiched and supported between the valve housing 41 and the fixed iron core 37. The ring-shaped temperature sensitive member 55 surrounding the transmission rod 40 in the valve accommodating chamber 411 is made of a shape memory alloy. A position regulating ring 56 is fixed to the transmission rod 40 in the valve accommodating chamber 411. The position restricting ring 56 can be brought into contact with and separated from the temperature sensitive member 55, and the temperature sensitive member 55 is provided on the advancing side of the position restricting ring 56 as the applied voltage to the coil 38 increases (increase in electromagnetic driving force). Yes. The position regulating ring 56 is an accessory member that moves integrally with the valve body 401.

  The temperature sensitive member 55 shown in FIG. 6A is in a martensitic phase. The situation where the temperature sensitive member 55 is in the martensitic phase is the situation where the electromagnetic capacity control valve 35 is below the martensitic transformation temperature.

  The temperature sensitive member 55 shown in FIG. 6B is in an austenite phase state. The temperature sensitive member 55 in the austenite phase has a flat plate shape. The situation where the temperature sensitive member 55 is in the austenite phase state corresponds to the temperature increase of the electromagnetic capacity control valve 35 accompanying the operation of the variable capacity compressor 10.

  The temperature sensitive member 55 is provided on the traveling side of the position restricting ring 56 that accompanies an increase in applied voltage to the coil 38 (an increase in electromagnetic driving force). The length L1 of the temperature sensitive member 55 in the movable direction R of the valve body 401 (shown in FIG. 6A) is the length when in the martensitic phase, and the length of the temperature sensitive member 55 in the movable direction R is The length L2 (shown in FIG. 6B) is the thickness of the flat plate-shaped temperature sensitive member 55, and is the length when in the austenite phase state.

In the second embodiment, the same effects as the items (1), (2), (4), and (5) in the first embodiment can be obtained.
Next, a third embodiment shown in FIGS. 7A and 7B will be described. The same reference numerals are used for the same components as those in the second embodiment, and detailed description thereof is omitted.

  In the third embodiment, a plurality of temperature sensitive members 57 made of bimetal are used instead of the temperature sensitive member 55 in the second embodiment. The position restricting ring 56 can be brought into contact with and separated from the temperature sensitive member 57, and the temperature sensitive member 57 is provided on the advancing side of the position restricting ring 56 as the applied voltage to the coil 38 increases (increase in electromagnetic driving force). Yes.

  The temperature sensitive member 57 shown in FIG. 7B is in a state where the temperature of the electromagnetic capacity control valve 35 is normal temperature. The temperature sensitive member 57 shown in FIG. 7A corresponds to the temperature rise of the electromagnetic capacity control valve 35 accompanying the operation of the variable capacity compressor 10.

  In the third embodiment, the same effect as in the second embodiment can be obtained. Further, the bimetallic temperature-sensitive member 57 continuously changes following the temperature rise and continuously changes the foremost limit position. In other words, the use of the temperature sensitive member 57 made of bimetal enables fine adjustment of the forefront limit position.

In the present invention, the following embodiments are also possible.
In the first embodiment, the urging spring 44 may be a temperature sensitive member instead of the temperature sensitive member 54. In this case, the spring receiver 43 is an attached member that moves integrally with the valve body 401.

In the first embodiment, only one of the rings 541 and 542 may be used as the temperature sensitive member.
A shape memory resin may be used as the shape memory member that is a temperature sensitive member.

The present invention may be applied to an electromagnetic capacity control valve that adjusts the passage sectional area of the discharge passage 34.
In place of the pressure-sensitive means 49 in the electromagnetic capacity control valve 35, a control valve provided with pressure-sensitive means sensitive to suction pressure may be used as the electromagnetic capacity control valve. The pressure sensing means sensitive to the suction pressure biases the valve body in a direction away from the valve hole. That is, the pressure-sensitive means that is sensitive to the suction pressure urges the valve opening degree of the electromagnetic capacity control valve to increase.

  The valve opening degree of the electromagnetic capacity control valve provided with the pressure sensing means sensitive to the suction pressure depends on the balance of the electromagnetic force generated by the solenoid, the spring force of the biasing spring 44 (see FIG. 2), and the biasing force of the pressure sensing means. Determined. When such a control valve is used as an electromagnetic control valve, the suction pressure is defined as a suction set pressure corresponding to voltage application control (duty ratio control).

  The present invention may be applied to a variable capacity compressor that obtains driving force from an external driving source via a clutch. In such a variable capacity compressor, when the clutch is in the connected state, the refrigerant circulates through the external refrigerant circuit even when the inclination angle of the swash plate is minimum. It is possible not to circulate through the external refrigerant circuit.

The technical idea that can be grasped from the embodiment described above will be described together with the effects thereof.
[1] The capacity control valve in the variable capacity compressor according to any one of claims 1 to 4, wherein the temperature sensitive member is a bimetal.

  Fine adjustment of the forefront limit position is possible.

1 shows a first embodiment, (a) is a side sectional view of the whole compressor. (B) is a sectional side view of a capacity control valve. The partial expanded side sectional view of a capacity control valve. The partial expanded side sectional view of a capacity control valve. The partial expanded side sectional view of a capacity control valve. The partial expanded side sectional view of a capacity control valve. The 2nd Embodiment is shown and (a) is a partial expanded side sectional view of a capacity control valve. (B) is a fragmentary sectional side view. The 3rd embodiment is shown and (a) and (b) are partial expanded side sectional views of a capacity control valve.

Explanation of symbols

  10: Variable capacity compressor. 121: Control pressure chamber. 131: A suction chamber as a suction pressure region. 132: A discharge chamber as a discharge pressure region. 33: Supply passage. 34 ... discharge passage. 35: Electromagnetic capacity control valve. 36 ... Solenoid. 37 ... Fixed iron core. 38 ... Coil. 39: A movable iron core as an accessory member. 40: Transmission rod. 401 ... Valve body. 50: A voltage application circuit constituting voltage changing means. 54, 55 ... Temperature sensitive members which are shape memory members. 541, 542 ... Ring. 56: A position regulating ring which is an attached member. 57: Temperature sensitive member. C: Control computer constituting voltage changing means. S1, S2 ... Front limit position. L1, L2 ... Length. R: Movable direction.

Claims (5)

The refrigerant in the discharge pressure region is supplied to the control pressure chamber through the supply passage, the refrigerant in the control pressure chamber is discharged to the suction pressure region through the discharge passage, and the pressure in the control pressure chamber is adjusted. A discharge capacity is controlled by regulating the pressure in the control pressure chamber, and an electromagnetic capacity control valve for adjusting a passage sectional area of the supply passage or the discharge passage is provided. In addition to the valve body of the electromagnetic capacity control valve, In the capacity control valve in the variable capacity compressor controlled by the voltage application control of the voltage changing means for applying a voltage to the solenoid coil of the electromagnetic capacity control valve,
A temperature sensitive member for restricting the movable range of the valve body is provided. The temperature control member is a capacity control valve in a variable displacement compressor that regulates and moves the foremost limit position backward while the temperature is lowered and advances the forefront limit position while the temperature is raised.   The temperature sensitive member is provided on the traveling side of the valve body as the voltage increases, or on the traveling side of an accessory member that moves integrally with the valve body, and the temperature sensitive member in the moving direction of the valve body. The length of the member is shortened in the middle of the temperature rise to advance the foremost limit position, and the length of the temperature sensitive member is lengthened in the middle of the temperature to be lowered to retract the foremost limit position. Item 2. A displacement control valve in the variable displacement compressor according to Item 1.   3. The displacement control valve in the variable displacement compressor according to claim 1, wherein the temperature sensitive member is provided between a fixed iron core and a movable iron core of the solenoid.   4. The capacity of the variable capacity compressor according to claim 3, wherein the valve body is provided on a transmission rod fixed to the movable iron core, and the temperature sensitive member is a ring inserted through the transmission rod. 5. Control valve.   The capacity control valve in the variable capacity compressor according to any one of claims 1 to 4, wherein the temperature sensitive member is a shape memory member.

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