JP2006052706A - Capacity control valve of variable displacement swash-plate compressor for vehicle air-conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a capacity control valve of a variable displacement swash-plate compressor for vehicle air-conditioner in which a vehicle engine is prevented from being overloaded at start-up of the engine. <P>SOLUTION: The capacity control valve comprises a pressure-sensing member, a valve element 18, a magnetic actuator, and a spring. The pressure-sensing member expands/contracts by sensing pressure in the suction chamber of the variable displacement swash-plate compressor. The valve element 18 opens/closes the communication path between the discharge chamber and a crankcase by being activated into engagement with the pressure-sensing member. The magnetic actuator regulates an operating point for opening/closing the valve by urging the valve element in the closing direction. The spring drives the pressure-sending member in the direction for the valve element to open the valve. Crankcase pressure is received at the rear of the contact side of the valve element to a valve seat. The crankcase pressure is regulated to control the discharge capacity of the variable displacement swash-plate compressor, and control the driving torque and the pressure in the suction-chamber. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a capacity control valve of a variable capacity swash plate compressor for a vehicle air conditioner driven by a vehicle engine.

The present applicant is a displacement control valve of a variable capacity swash plate compressor for a vehicle air conditioner driven by a vehicle engine, and a pressure sensitive member that expands and contracts by sensing the suction chamber pressure of the variable displacement swash plate compressor, A valve body that is operatively engaged with the pressure-sensitive member to open and close the communication path between the discharge chamber and the crank chamber of the variable capacity swash plate compressor, and opens and closes the valve body by urging the valve body in the valve closing direction. An electromagnetic actuator that adjusts the operating point, and a spring that drives the pressure-sensitive member in the direction in which the valve element opens, and the surface of the valve element that contacts the valve seat and the opposite surface receive the crank chamber pressure. Patent Document 1 proposes a capacity control valve for a variable capacity swash plate compressor for a vehicle air conditioner that controls the discharge capacity of the variable capacity swash plate compressor by adjusting the crank chamber pressure.
The displacement control valve of the variable displacement swash plate compressor disclosed in Patent Document 1 can uniquely control the suction chamber pressure with respect to the urging force of the electromagnetic actuator, and forcibly discharge the electromagnetic actuator by stopping energization of the electromagnetic actuator. Has the advantage that it can be maintained at a minimum capacity.
JP-A-11-107929

The suction chamber pressure control performed by the displacement control valve of the variable displacement swash plate compressor of Patent Document 1 has the advantage that the cabin temperature can be maintained comfortably, but the discharge of the compressor according to the fluctuation of the heat load of the air conditioner Because the capacity fluctuates and the compressor driving torque fluctuates, the engine torque at the time of vehicle engine start-up or sudden acceleration when the engine torque does not have sufficient capacity is borne by the vehicle engine so that the engine starts or suddenly accelerates. Has the disadvantage that it may hinder. In addition, a sudden increase in engine torque causes discomfort to the occupant.
The present invention has been made in view of the above problems, and includes a pressure-sensitive member that expands and contracts by sensing the suction chamber pressure of a variable displacement swash plate compressor, and a variable displacement swash plate compressor that is operatively engaged with the pressure sensitive member. Valve body that opens and closes the communication path between the discharge chamber and the crank chamber, an electromagnetic actuator that urges the valve body in the valve closing direction to adjust the opening and closing operation point of the valve body, and the direction in which the valve body opens And a spring that drives the pressure sensitive member, and the surface of the valve body that contacts the valve seat receives the crank chamber pressure and adjusts the crank chamber pressure to discharge the variable capacity swash plate compressor. This is a capacity control valve for a variable capacity swash plate compressor for a vehicle air conditioner that is driven by a vehicle engine to control the capacity, and may cause an excessive load on the vehicle engine when the vehicle engine is started or suddenly accelerated. And the occupant by suppressing a sudden torque increase of the vehicle engine And to provide a displacement control valve that can suppress discomfort.

In order to solve the above-mentioned problems, in the present invention, a pressure-sensitive member that expands and contracts by sensing the suction chamber pressure of a variable displacement swash plate compressor, and a variable displacement swash plate compressor that is operatively engaged with the pressure-sensitive member. A valve body that opens and closes the communication path between the discharge chamber and the crank chamber, an electromagnetic actuator that urges the valve body in the valve closing direction to adjust the opening / closing operation point of the valve body, and a direction in which the valve body opens A spring that drives the pressure-sensitive member, and a surface that contacts the valve seat of the valve body and a surface on the opposite side receive the crank chamber pressure, and adjust the crank chamber pressure to discharge the displacement of the variable capacity swash plate compressor A capacity control valve of a variable capacity swash plate compressor for a vehicle air conditioner that is driven by a vehicle engine and that can control the driving torque and suction chamber pressure of the variable capacity swash plate compressor I will provide a.

Since the capacity control valve according to the present invention can control the compressor driving torque in addition to the suction chamber pressure control, the compressor driving torque can be set at the time of start-up or sudden acceleration of the vehicle engine where there is no surplus in the engine torque. By controlling to a minute value, the load applied to the vehicle engine can be reduced, and an abrupt increase in torque of the vehicle engine can be suppressed to reduce occupant discomfort. On the other hand, during normal driving of a vehicle having a surplus in the torque of the vehicle engine, it is possible to control the suction chamber pressure of the compressor and maintain the passenger compartment temperature comfortably.

In the present invention, a pressure-sensitive member that expands and contracts by sensing the suction chamber pressure of a variable capacity swash plate compressor, and a pressure-sensitive member that is operatively engaged with the pressure-sensitive member between the discharge chamber and the crank chamber of the variable capacity swash plate compressor. A valve body that opens and closes the communication path, an electromagnetic actuator that urges the valve body in the valve closing direction to adjust the opening and closing operation point of the valve body, and a spring that drives the pressure sensitive member in the direction in which the valve body opens Driven by the vehicle engine, the surface of the valve body that contacts the valve seat and the surface on the opposite side receive the crank chamber pressure, and adjust the crank chamber pressure to control the discharge capacity of the variable capacity swash plate compressor The displacement control valve of the variable capacity swash plate compressor for a vehicle air conditioner, wherein the pressure sensitive member receives the pressure in the discharge chamber and is driven in a direction to open the valve body, and the valve body is closed. Capacity control comprising a regulating member that regulates movement of the pressure-sensitive member in the direction of movement To provide.

When the vehicle engine is stopped, the compressor is stopped and the energization of the electromagnetic actuator is also stopped. The gas pressure applied to the valve body and the pressure sensitive member is balanced. The pressure-sensitive member is reduced to the minimum size in response to a high suction chamber pressure. The pressure sensitive member receives the biasing force of the spring and moves in a direction in which the valve element opens, and the valve element opens a communication path between the discharge chamber and the crank chamber.

When the vehicle engine is started, the valve body opens the communication path between the discharge chamber and the crank chamber, so that the differential pressure between the crank chamber pressure at which the discharge chamber pressure is introduced and the suction chamber pressure increases. The compressor starts operation with the minimum discharge capacity.
When the electromagnetic actuator is energized, the valve body moves in the valve closing direction against the biasing force of the spring that biases the pressure-sensitive member, and closes the communication path between the discharge chamber and the crank chamber. If the biasing force of the spring is set to a small value, a minute current can be applied to close the valve element. The pressure-sensitive member moves in the direction in which the valve element closes while maintaining the state reduced to the minimum dimension. By closing the valve body, the communication between the discharge chamber and the crank chamber is cut off, the differential pressure between the crank chamber pressure and the suction chamber pressure is reduced, and the discharge capacity of the compressor is increased. As the discharge capacity increases, the suction chamber pressure applied to the pressure sensitive member decreases and the discharge chamber pressure increases. The pressure-sensitive member to which the differential pressure between the discharge chamber pressure and the suction chamber pressure is applied moves in the direction in which the valve element opens while gradually expanding, and opens the valve element.
When the valve element opens, the discharge capacity of the compressor decreases, the differential pressure between the discharge chamber pressure and the suction chamber pressure decreases, and the pressure sensitive member moves in the direction in which the valve element closes. Since the urging force of the electromagnetic actuator in the valve closing direction is small, the pressure-sensitive member does not move to a position where it comes into contact with the regulating member. Therefore, the movement of the pressure sensitive member in the valve closing direction is not restricted.
The reciprocating movement of the pressure-sensitive member and the opening and closing of the valve body are repeated, the discharge capacity of the compressor is controlled to increase or decrease, and the differential pressure between the discharge chamber pressure and the suction chamber pressure corresponds to the amount of current supplied to the electromagnetic actuator Asymptotically. The differential pressure between the discharge chamber pressure and the suction chamber pressure has a correlation with the refrigerant circulation amount, and consequently with the driving torque of the compressor. Therefore, the amount of current supplied to the electromagnetic actuator is controlled to a minute value to drive the compressor. By controlling the torque to a small value, the load on the vehicle engine is reduced when the vehicle engine starts up or suddenly accelerates, where there is no surplus in the torque of the vehicle engine. It is possible to reduce a passenger's discomfort by suppressing a rapid torque increase of the vehicle engine.

During normal traveling of a vehicle having a surplus vehicle engine torque, the energization amount to the electromagnetic actuator is increased to a predetermined value, and the pressure sensitive member is driven in the valve closing direction. The pressure sensitive member comes into contact with the regulating member, and the movement of the pressure sensitive member in the valve closing direction is regulated by the regulating member. Since the movement of the pressure-sensitive member is restricted in the energization amount region larger than the predetermined value, the discharge chamber pressure and the spring biasing force applied to the pressure-sensitive member are invalid with respect to the discharge amount control. The communication between the discharge chamber and the crank chamber is cut off, the discharge capacity is increased, and the suction chamber pressure is further reduced, whereby the pressure-sensitive member is extended and the valve body is urged in the valve opening direction. When the valve element opens, the discharge chamber and the crank chamber communicate with each other, and the discharge capacity decreases. When the discharge capacity decreases, the suction chamber pressure increases and the pressure sensitive member is reduced. When the pressure sensitive member shrinks, the valve body closes. The expansion and contraction of the pressure-sensitive member and the opening and closing of the valve body are repeated, the discharge capacity of the compressor is controlled to increase or decrease, and the suction chamber pressure gradually approaches a value corresponding to the energization amount to the electromagnetic actuator. Since the suction chamber pressure has a correlation with the passenger compartment temperature, the passenger compartment temperature can be maintained comfortably by controlling the amount of current supplied to the electromagnetic actuator.

As can be seen from the above description, the capacity control valve according to the present invention controls the compressor drive torque to a minute value when the vehicle engine starts up or suddenly accelerates when the vehicle engine torque has no surplus. While reducing the applied load, it is possible to reduce a passenger's discomfort by suppressing a rapid torque increase of the vehicle engine. On the other hand, during normal driving of a vehicle having a surplus in the torque of the vehicle engine, it is possible to control the suction chamber pressure of the compressor and maintain the passenger compartment temperature comfortably.

Since the capacity control valve according to the present invention can control the compressor driving torque in addition to the suction chamber pressure control, the compressor driving torque can be set at the time of start-up or sudden acceleration of the vehicle engine where there is no surplus in the engine torque. By controlling to a minute value, the load applied to the vehicle engine can be reduced, and an abrupt increase in torque of the vehicle engine can be suppressed to reduce occupant discomfort. During normal driving of a vehicle having a surplus in the torque of the vehicle engine, the suction chamber pressure of the compressor can be controlled to maintain the passenger compartment temperature comfortably.

A capacity control valve of a variable capacity swash plate compressor for a vehicle air conditioner according to an embodiment of the present invention will be described.

As shown in FIG. 1, a capacity control valve of a variable capacity swash plate compressor for a vehicle air conditioner driven by a vehicle engine is disposed in a valve casing 11 and the valve casing 11, and the inside is evacuated. A bellows 12 provided with a spring, a guide 13a fixed to the lower end of the bellows 12 in the figure and supported movably on the valve casing 11, a spring 14 for urging the guide 13a upward in the figure, and the valve casing 11 A part of the valve casing 11 is formed by screwing, and an adjustment screw 15 for adjusting the expansion / contraction amount of the bellows 12 and a guide 13 a are formed integrally with the guide 13 a and the valve casing 11. A cylindrical portion 13c that forms a small-diameter pressure-sensitive chamber 13b that is pressure-isolated from the other portion, and one end abuts on the upper end of the bellows 12 in the figure and is supported by the valve casing 11 so as to be movable. A transmission rod 16, a valve body 18 that contacts the other end of the transmission rod 16 and opens and closes the communication passage 17 between the discharge chamber and the crank chamber of the variable capacity swash plate compressor according to the expansion and contraction of the bellows 12; An electromagnetic coil 21 for generating an electromagnetic force that urges the valve body 18 in the valve closing direction via the plunger 19 and the transmission rod 20 is provided.
The surface 18 b opposite to the contact surface 18 a with the valve seat of the valve body 18 receives the crank chamber pressure via the pressure guide path 22 connected to the communication path 17. The contact surface 18a receives the crank chamber pressure. The crank chamber pressure receiving area of the contact surface 18a and the crank chamber pressure receiving area of the surface 18b are set to be equal. The peripheral side surface 18c of the valve body 18 is movably supported by the valve casing 11, and the gap between the peripheral side surface 18c and the valve body support hole peripheral wall of the valve casing 11 is set to a minimum value.

The operation of the capacity control valve will be described.
When the vehicle engine is stopped, the variable capacity swash plate compressor for the vehicle air conditioner is stopped and the energization of the electromagnetic coil 21 is also stopped. The gas pressure applied to the pressure sensitive member constituted by the valve body 18, the bellows 12, the guide 13a, and the cylindrical portion 13c is balanced. As shown in FIG. 1A, the bellows 12 constituting the pressure-sensitive member is reduced to the minimum dimension in response to a high suction chamber pressure. The pressure sensitive member receives the biasing force of the spring 14 and moves away from the end of the valve casing 11 in the valve opening direction of the valve body 18, which opens the communication passage 17 between the discharge chamber and the crank chamber. ing.

When the vehicle engine is started, the valve body 18 opens the communication passage 17 between the discharge chamber and the crank chamber, so that the differential pressure between the crank chamber pressure at which the discharge chamber pressure is introduced and the suction chamber pressure increases. Then, the compressor starts operation with the minimum discharge capacity.
When the electromagnetic coil 21 is energized, the valve element 18 moves in the valve closing direction against the biasing force of the spring 14 that biases the pressure-sensitive member, and closes the communication path 17 between the discharge chamber and the crank chamber. If the biasing force of the spring 14 is set to a small value, the valve element 18 can be closed by energizing a minute current. Since the suction chamber pressure is still high, the bellows 12 and thus the pressure-sensitive member move in the direction in which the valve element 18 closes while maintaining the reduced state to the minimum dimension.
When the valve body 18 is closed, the communication between the discharge chamber and the crank chamber is cut off, the differential pressure between the crank chamber pressure and the suction chamber pressure is reduced, and the discharge capacity of the compressor is increased. . As the discharge capacity increases, the suction chamber pressure applied to the pressure sensitive member decreases and the discharge chamber pressure increases. The pressure sensitive member gradually expands. Since the biasing force due to the crank chamber pressure applied to the surface 18a of the valve body 18 and the biasing force due to the crank chamber pressure applied to the surface 18b cancel each other, the discharge chamber pressure does not act in the axial direction of the valve body 18, The valve body 18 corresponds to the magnitude relationship between the sum of the biasing force due to the pressure difference between the discharge chamber pressure applied to the pressure-sensitive member and the suction chamber pressure and the biasing force of the spring 14 and the biasing force generated by the electromagnetic coil 21. Then, the communication path 17 is opened and closed. When the sum of the biasing force due to the differential pressure between the discharge chamber pressure and the suction chamber pressure applied to the pressure-sensitive member and the biasing force of the spring 14 exceeds the biasing force generated by the electromagnetic force of the electromagnetic coil 21, the pressure-sensitive member is Then, the valve body 18 is moved in the opening direction to open the valve body 18. When the valve body 18 is opened, the discharge capacity of the compressor decreases, the differential pressure between the discharge chamber pressure and the suction chamber pressure decreases, and the differential pressure between the discharge chamber pressure and the suction chamber pressure applied to the pressure sensitive member. The sum of the urging force by the spring 14 and the urging force of the spring 14 becomes less than the urging force generated by the electromagnetic coil 21, and the pressure-sensitive member moves in the direction in which the valve element closes. Since the energization amount to the electromagnetic coil 21 is very small and the biasing force generated by the electromagnetic coil 21 in the valve closing direction is small, the pressure-sensitive member guide portion 13a and the cylinder 13b are located at the end of the valve casing 11. Without contact, the pressure sensitive member maintains a state separated from the end of the valve casing 11. Therefore, the movement of the pressure sensitive member in the valve body closing direction is not restricted by the end of the valve casing 11. The reciprocating movement of the pressure sensitive member and the opening and closing of the valve body 18 are repeated, the discharge capacity of the compressor is controlled to increase or decrease, and the differential pressure between the discharge chamber pressure and the suction chamber pressure corresponds to the amount of current supplied to the electromagnetic coil 21. Asymptotic to the value to be.
The pressure difference between the discharge chamber pressure and the suction chamber pressure has a correlation with the refrigerant circulation amount, and consequently has a correlation with the driving torque of the compressor. Therefore, the energization amount to the electromagnetic coil 21 is controlled to a minute value, By controlling the drive torque to a minute value, it is possible to reduce the load applied to the vehicle engine when starting the vehicle engine having no surplus in the torque of the vehicle engine, and to complete the engine startup without any trouble.

During normal travel of the vehicle having a surplus in the torque of the vehicle engine, the energization amount to the electromagnetic actuator is increased to a predetermined value and the pressure sensitive member is driven in the valve closing direction. As shown in FIG. 1 (b), the guide portion 13a and the tube portion 13b of the pressure sensitive member abut against the end portion of the valve casing 11, and the movement of the pressure sensitive member in the valve body 18 valve closing direction is restricted. . Since the pressure receiving area of the pressure sensing chamber 13b is small, the pressure sensing member can be brought into contact with the end of the valve casing 11 with a relatively small amount of energization. Since the movement of the pressure-sensitive member is restricted in the energization amount region larger than the predetermined value, the urging force due to the discharge chamber pressure applied to the pressure-sensitive member and the urging force of the spring 14 are invalid with respect to the discharge amount control. become. Since the biasing force due to the crank chamber pressure applied to the surface 18a of the valve body 18 and the biasing force due to the crank chamber pressure applied to the surface 18b cancel each other, the discharge chamber pressure does not act in the axial direction of the valve body 18, The valve body 18 opens and closes the communication path 17 in accordance with the magnitude relationship between the suction chamber pressure applied to the bellows 12 of the pressure-sensitive member and the urging force generated by the electromagnetic coil 21.
The communication between the discharge chamber and the crank chamber is cut off, the discharge capacity is increased, and the suction chamber pressure is further reduced, whereby the pressure sensitive member is extended and the valve body 18 is urged in the valve opening direction. When the valve body 18 is opened, the discharge chamber and the crank chamber communicate with each other, and the discharge capacity decreases. When the discharge capacity decreases, the suction chamber pressure increases and the pressure sensitive member is reduced. When the pressure sensitive member is reduced, the valve element 18 is closed. The expansion and contraction of the pressure sensitive member and the opening and closing of the valve body 18 are repeated, the discharge capacity of the compressor is controlled to increase and decrease, and the suction chamber pressure gradually approaches a value corresponding to the energization amount to the electromagnetic coil 21. Since the suction chamber pressure has a correlation with the passenger compartment temperature, the passenger compartment temperature can be maintained comfortably by controlling the amount of current supplied to the electromagnetic actuator.

FIG. 2 shows the operating characteristics of the capacity control valve according to this embodiment. As can be seen from FIG. 2 in addition to the above description, the displacement control valve according to the present embodiment is configured such that the differential pressure between the discharge chamber pressure and the suction chamber pressure is electromagnetic when the energization amount to the electromagnetic coil 21 is a predetermined value or less. When the discharge capacity of the compressor is controlled so as to be a value corresponding to the energization amount to the coil 21 and the energization amount to the electromagnetic coil 21 exceeds a predetermined value, the suction chamber pressure corresponds to the energization amount to the electromagnetic coil 21. The discharge capacity of the compressor is controlled so as to be a value to be adjusted. Therefore, in the capacity control valve according to the present embodiment, by appropriately controlling the energization amount to the electromagnetic coil 21, the discharge chamber pressure and the exhaust chamber pressure can be reduced at the time of starting or sudden acceleration of the vehicle engine where there is no surplus in the torque of the vehicle engine. By controlling the differential pressure with respect to the suction chamber pressure and thus the compressor drive torque to a very small value, the load on the vehicle engine is reduced, and a sudden increase in torque of the vehicle engine is suppressed to reduce passenger discomfort. On the other hand, during normal driving of the vehicle having a surplus in the torque of the vehicle engine, the suction chamber pressure of the compressor can be controlled to maintain the passenger compartment temperature comfortably.

The present invention is widely applicable to a capacity control valve of a variable capacity swash plate compressor for a vehicle air conditioner driven by a vehicle engine.

It is sectional drawing of the capacity | capacitance control valve of the variable capacity | capacitance swash plate type compressor for vehicle air conditioners which concerns on the Example of this invention. It is an operation characteristic figure of the capacity control valve of the variable capacity swash plate type compressor for vehicle air conditioners concerning the example of the present invention.

Explanation of symbols

11 Valve casing 12 Bellows 13a Guide 13b Pressure sensing chamber 13c Tube portion 14 Spring 15 Screws 16 and 20 Transmission rod 17 Communication passage 18 Valve element 19 Plunger 21 Electromagnetic coil 22 Pressure guiding path

Claims (2)

A pressure-sensitive member that expands and contracts by sensing the suction chamber pressure of the variable capacity swash plate compressor, and opens and closes the communication path between the discharge chamber and the crank chamber of the variable capacity swash plate compressor by operative engagement A valve body, an electromagnetic actuator that urges the valve body in a valve closing direction to adjust an opening / closing operation point of the valve body, and a spring that drives a pressure-sensitive member in a direction in which the valve body opens. A vehicle air conditioner driven by a vehicle engine for controlling the discharge capacity of the variable capacity swash plate compressor by receiving the crank chamber pressure by the surface abutting on the valve seat and the surface opposite to the valve seat and adjusting the crank chamber pressure A capacity control valve for a variable capacity swash plate compressor for an apparatus, which is capable of controlling a drive torque and a suction chamber pressure of the variable capacity swash plate compressor. A pressure-sensitive member that expands and contracts by sensing the suction chamber pressure of the variable capacity swash plate compressor, and opens and closes the communication path between the discharge chamber and the crank chamber of the variable capacity swash plate compressor by operating engagement with the pressure sensitive member. A valve body, an electromagnetic actuator that urges the valve body in a valve closing direction to adjust an opening / closing operation point of the valve body, and a spring that drives a pressure-sensitive member in a direction in which the valve body opens. A vehicle air conditioner driven by a vehicle engine for controlling the discharge capacity of the variable capacity swash plate compressor by receiving the crank chamber pressure by the surface abutting on the valve seat and the surface opposite to the valve seat and adjusting the crank chamber pressure A displacement control valve for a variable displacement swash plate compressor for a device, wherein the pressure sensitive member receives the discharge chamber pressure and is driven in a direction in which the valve body opens, and in the direction in which the valve body closes. A capacity control valve comprising a restricting member for restricting movement of the pressure member.

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