JP2000220577A - Displacement control method and device for variable displacement compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the generation of clashing sound in the maximum or minimum inclining angle position of a swash plate. SOLUTION: When current supply to an electrical displacement control valve 39 is started by the ON operation of an air conditioner operation switch 44, a control computer C1 performs buffering current supply starting control for gradually increasing the value of a current supplied to the solenoid 43 of the displacement control valve 39 from a zero supply current value to a specified supply current value. When current supply to the electrical displacement control valve 39 is stopped by the OFF operation of the air conditioner operation switch 44, the control computer C1 performs buffering current supply stopping control for gradually reducing the value of a current supplied to the solenoid 43 of the displacement control valve 39 from the specified supply current value immediately before the turning-OFF of the air conditioner operation switch 44 to the zero supply current value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a capacity control method and apparatus for a variable displacement compressor.

[0002]

2. Description of the Related Art In a variable displacement compressor disclosed in Japanese Patent Application Laid-Open No. 8-338364, a displacement is changed based on a differential pressure between a pressure in a crank chamber and a suction pressure in a suction pressure region. . The pressure in the crank chamber is adjusted by supplying the refrigerant from the discharge chamber, which is the discharge pressure area, to the crank chamber, and extracting the refrigerant from the crank chamber to the suction chamber, which is the suction pressure area. An electromagnetic valve for capacity control is interposed on the pressure supply passage for supplying the refrigerant from the discharge chamber to the crank chamber. The valve body of the solenoid valve is urged toward the valve closing position by the excitation of the solenoid. The supply current value to the solenoid valve is determined based on a comparison between a preset room temperature and a detected room temperature. As the difference between the set room temperature and the detected room temperature increases, the supply current value increases, and the valve opening of the solenoid valve decreases. As the valve opening decreases, the inclination angle of the swash plate increases, and the discharge capacity increases. When the valve element is located at the valve closing position, the pressure supply passage is closed, and the supply of the refrigerant from the discharge chamber to the crank chamber stops. Therefore, the inclination angle of the swash plate becomes the maximum inclination angle. When the solenoid is demagnetized, the valve body moves to the position of the maximum valve opening, and the supply of refrigerant from the discharge chamber to the crank chamber increases. Therefore, the pressure in the crank chamber increases, and the inclination angle of the swash plate is minimized. In the minimum inclination state of the swash plate, the shut-off body that is linked to the inclination of the swash plate closes the suction passage, and the circulation of the refrigerant in the external refrigerant circuit stops.
This refrigerant circulation stop state is a state in which there is no heat load reducing action.

[0003]

Normally, when the air conditioner operation switch is turned on, the difference between the set room temperature and the detected room temperature is large, and the supply current value to the solenoid valve becomes large from the time the air conditioner operation switch is turned on. As a result, the swash plate inclination may increase sharply from the minimum inclination, and the swash plate may quickly move to the maximum inclination through the swash plate inclination corresponding to the selected supply current value. Such passing causes a collision between the swash plate and a member that defines the maximum inclination angle of the swash plate, and a collision sound is generated. When the air conditioner operation switch is turned off when the difference between the set room temperature and the detected room temperature is large, the current supplied to the solenoid valve is instantaneously switched from a large value to zero. Therefore, the swash plate inclination angle rapidly decreases from a large inclination angle, and the swash plate quickly moves to the minimum inclination position. Such a quick transition causes a collision between the swash plate and a member defining the minimum inclination of the swash plate, and a collision sound is generated.

SUMMARY OF THE INVENTION It is an object of the present invention to prevent the occurrence of the above-described collision noise when the current supply to the capacity control valve is started or stopped.

[0005]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a swash plate housed in a control pressure chamber so as to rotate integrally with a rotating shaft and to be variably inclined with respect to the rotating shaft, and the swash plate. A piston that performs a reciprocating operation in accordance with the tilt angle of the refrigerant, supplies a refrigerant from the discharge pressure area to the control pressure chamber, extracts the refrigerant from the control pressure chamber to the suction pressure area, and controls the control pressure chamber from the discharge pressure area. An electric capacity control valve is interposed on the refrigerant supply passage leading to the refrigerant passage or on the refrigerant extraction passage leading from the control pressure chamber to the suction pressure region, and controls a supply current value (per unit time) to the electric capacity control valve. Controlling the amount of refrigerant supplied from the discharge pressure area to the control pressure chamber or the amount of refrigerant withdrawn from the control pressure chamber to the suction pressure area, and controlling the inclination of the swash plate based on control of the pressure in the control pressure chamber. Variable capacity to control The present invention is directed to a compressor, and in the invention according to claim 1, when starting current supply to the electric capacity control valve, as a process until starting supply of a specified supply current value, the swash plate at a maximum inclination position is started. A buffer current supply start control for suppressing the inclination increasing speed is performed.

According to the second aspect of the present invention, in the first aspect,
The buffer current supply start control increases a supply current value from a supply current value of zero to a designated supply current value, and the buffer current supply start control includes a supply current value of zero to the designated supply current value. The current increasing supply state in which the supply current value gradually increases in at least a part of the range.

According to a third aspect of the present invention, in the second aspect,
The buffer current supply start control includes a supply current value switching state in which the supply current value is discontinuously switched from a supply current value of zero to an increase jump limit supply current value that does not reach the designated supply current value, and the increase jump limit supply. And a current increasing supply state in which the supply current value is gradually increased from the current value to the specified supply current value.

According to the present invention, when the current supply to the electric capacity control valve is stopped, the inclination decreasing speed at the minimum inclination position of the swash plate is suppressed until the supply current value becomes zero. Control for stopping the supply of current for buffering is performed.

According to a fifth aspect of the present invention, in the fourth aspect,
The buffering current supply stop control reduces the supply current value from a specified designated supply current value to a supply current value of zero, and the buffering current supply stop control reduces the supply current value from the designated supply current value to a supply current value of zero. And a current decreasing supply state in which the supply current value is gradually decreased in at least a part of the range.

According to the invention of claim 6, in claim 5,
The buffering current supply stop control includes a supply current value switching state in which the supply current value is discontinuously switched from the specified supply current value to a decrease jump limit supply current value that does not reach the designated supply current value, and the decrease jump limit. And a current decreasing supply state in which the supply current value gradually decreases from the supply current value to the supply current value of zero.

According to a seventh aspect of the present invention, the current supply start command means for commanding the start of the current supply to the electric capacity control valve, and a buffer for suppressing the inclination increasing speed at the maximum inclination position of the swash plate. Constituting a capacity control device comprising a buffer current supply start control means for performing a current supply start control,
The buffer current supply start control means performs the buffer current supply start control based on a current supply start command of the current supply start command means.

According to the invention of claim 8, in claim 7,
A capacity control device comprising a supply current value designating means for designating a supply current value is constituted, and the buffer current supply start control means comprises a supply current value zero up to a designated supply current value designated by the supply current value designation means. And the supply current value is increased and the supply current value is gradually increased in at least a part of the range from the supply current value of zero to the specified supply current value.

According to a ninth aspect of the present invention, in the eighth aspect,
The buffer current supply start control means discontinuously switches the supply current value from a supply current value of zero to an increase jump limit supply current value that does not reach the designated supply current value, and changes the supply current value from the increase jump limit supply current value to the designated supply current value. Current supply start control for gradually increasing the supply current value up to the supply current value is performed. According to a tenth aspect of the present invention, a current supply stop command means for commanding a stop of the current supply to the electric capacity control valve, and a buffer current supply stop for suppressing the inclination decreasing speed at the minimum inclination position of the swash plate. And a buffer current supply stop control means for performing a control. The buffer current supply stop control means is configured to control the buffer current supply based on a current supply stop command of the current supply stop command means. Stop control is performed.

According to an eleventh aspect of the present invention, in accordance with the tenth aspect, the capacity control device comprises a supply current value designating means for designating a supply current value, wherein the buffering current supply stop control means comprises: Reducing the supply current value from the designated supply current value designated by the designation means to the supply current value of zero,
In addition, current supply stop control for gradually decreasing the supply current value in at least a part of the range from the designated supply current value to the supply current value of zero is performed.

According to a twelfth aspect of the present invention, in the eleventh aspect, the buffer current supply stop control means changes the supply current value from the designated supply current value to a reduced jump limit supply current value that does not reach the designated supply current value. The current supply is stopped discontinuously, and the current supply stop control is performed so that the supply current value is gradually reduced from the decrease jump limit supply current value to the supply current value of zero.

According to the first and seventh aspects of the present invention, when the current supply to the electric capacity control valve is started, the buffer current supply start control is performed to suppress a sharp increase in the swash plate inclination angle. The suppression of the rapid increase of the swash plate inclination by the buffer current supply start control is to avoid unnecessary arrival of the swash plate at the maximum inclination position or to suppress the inclination increasing speed when the swash plate reaches the maximum inclination position. Bring.

According to the second and eighth aspects of the present invention, the current supply is performed by gradually increasing the supply current value in at least a part of the range from the supply current value of zero to the specified supply current value. The current supply state including the current increase supply state in which the supply current value is gradually increased suppresses a sharp increase in the swash plate inclination angle.

According to the third and ninth aspects of the present invention, after the supply current value is discontinuously switched from zero to the increase jump limit supply current value that does not reach the specified supply current value, the increase jump limit supply current value From the specified supply current value to the specified supply current value. The current supply state including the current increase supply state in which the supply current value is gradually increased suppresses a sharp increase in the swash plate inclination angle. The discontinuous switching of the supply current value from the supply current value zero to the increase jump limit supply current value contributes to the rapid increase of the discharge capacity.

According to the fourth and tenth aspects of the present invention, when the current supply to the electric capacity control valve is stopped, the buffer current supply stop control is performed to suppress a sharp decrease in the inclination angle of the swash plate. The suppression of the rapid decrease of the swash plate inclination by the buffer current supply stop control leads to the suppression of the inclination decreasing speed when the swash plate reaches the minimum inclination position.

According to the fifth and eleventh aspects of the present invention, the current decreasing supply is performed in which the supply current value is gradually reduced in at least a part of the range from the designated supply current value to the supply current value of zero. The current supply state including the current decrease supply state in which the supply current value is gradually reduced suppresses a sharp decrease in the swash plate inclination angle.

According to the sixth and twelfth aspects of the present invention, after the supply current value is discontinuously switched from the specified supply current value to the decrease jump limit supply current value, the supply current value becomes zero from the decrease jump limit supply current value. A current decreasing supply is performed in which the supply current value is gradually reduced until the current decreases. The current supply state including the current decrease supply state in which the supply current value is gradually reduced suppresses a sharp decrease in the swash plate inclination angle. The discontinuous switching from the designated supply current value to the increase jump limit supply current value contributes to a rapid decrease in the discharge capacity.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment in which the present invention is embodied in a clutchless variable displacement compressor mounted on a vehicle will be described below with reference to FIGS.

As shown in FIG. 1, the cylinder block 11
A front housing 12 is joined to a front end of the front housing 12.
A rear housing 13 is joined and fixed to the rear end of the cylinder block 11 via a valve plate 14, valve forming plates 15, 16 and a retainer forming plate 17.
The rotary shaft 18 erected and supported between the front housing 12 forming the control pressure chamber 121 and the cylinder block 11
Obtains a rotational driving force from a vehicle engine (not shown).

A swash plate 20 is supported on the rotating shaft 18 so as to be slidable and tiltable in the axial direction of the rotating shaft 18.
As shown in FIG. 4, the guide pin 2 fixed to the swash plate 20
The heads 3 and 24 are slidably fitted into guide holes 191 and 192 of a rotation support 19 fixed to the rotation shaft 18. The swash plate 20 can be tilted in the axial direction of the rotating shaft 18 and can rotate integrally with the rotating shaft 18 by linking the guide holes 191 and 192 and the guide pins 23 and 24.
When the center of the radius of the swash plate 20 moves toward the cylinder block 11, the inclination angle of the swash plate 20 decreases. The inclination reducing spring 25 interposed between the rotating support 19 and the swash plate 20
The swash plate 20 is biased in a direction to decrease the inclination angle of zero.

As shown in FIGS. 1 and 3, a cylindrical blocking body 22 is slidably accommodated in an accommodation hole 21 formed through the center of the cylinder block 11. Blocker 2
The suction passage opening spring 26 interposed between the end face 2 and the end face of the housing hole 21 urges the blocking body 22 toward the swash plate 20.
The rear end of the rotating shaft 18 is supported on the peripheral surface of the housing hole 21 via the radial bearing 27 and the blocking body 22. A suction passage 31 formed at the center of the rear housing 13 is connected to the housing hole 21. When the distal end surface of the blocking body 22 contacts the valve forming plate 15, the blocking body 22 is
Movement in the direction away from is restricted. As the swash plate 20 moves toward the blocking body 22, the tilt of the swash plate 20 is transmitted to the blocking body 22 via the thrust bearing 37. The rotation of the swash plate 20 is prevented from being transmitted to the interrupter 22 by the presence of the thrust bearing 37. By this tilting transmission, the blocking body 22 moves toward the valve forming plate 15 against the spring force of the suction passage opening spring 26, and the blocking body 22 contacts the valve forming plate 15, as shown in FIG. The minimum inclination angle of the swash plate 20 is defined by the contact between the blocking body 22 and the valve forming plate 15. FIG. 3 shows the swash plate 20 in the minimum inclination state.
FIG. 1 shows the swash plate 20 in the maximum inclination state. The maximum inclination angle of the swash plate 20 is defined by the contact between the swash plate 20 and the rotary support 19.

The piston 28 is accommodated in a cylinder bore 111 penetrating through the cylinder block 11. The rotational motion of the swash plate 20 is converted into a reciprocating motion of the piston 28 via the shoe 29, and the piston 28 moves back and forth in the cylinder bore 111.

As shown in FIG. 5, a suction chamber 131 serving as a suction pressure area and a discharge chamber 132 serving as a discharge pressure area are formed around the suction chamber 131 in the rear housing 13. A suction port 141 and a discharge port 142 are formed in the valve plate 14. 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 pushes back the suction valve 151 from the suction port 141 by the reciprocating operation of the piston 28 and flows into the cylinder bore 111. The refrigerant flowing into the cylinder bore 111 is discharged from the discharge port 142 by the forward movement of the piston 28 to the discharge valve 1.
61 is displaced and discharged to the discharge chamber 132. Discharge valve 1
The opening 61 is restricted in contact with the retainer 171 on the retainer forming plate 17.

Rotary support 19 and front housing 12
The thrust bearing 32 interposed between the piston bore 28, the shoe 29, and the swash plate 20 extends from the cylinder bore 111.
And receives the compression reaction force acting on the rotary support 19 via the guide pins 23 and 24.

The passage 50 in the rotary shaft 18 has a control pressure chamber 121.
And the inside of the cylinder of the blocking body 22. As shown in FIG. 3, a pressure release port 221 penetrating through the peripheral surface of the blocking body 22 communicates the inside of the cylinder of the blocking body 22 with the housing hole 21.

The suction chamber 131 communicates with the receiving hole 21 through the opening 143. The blocking body 22 is the valve forming plate 15
, The communication port 143 is shut off from the suction passage 31. The suction passage 31 for introducing the refrigerant into the suction chamber 131 and the discharge chamber 132 are connected by an external refrigerant circuit 33. On the external refrigerant circuit 33, a condenser 34, an expansion valve 35, and an evaporator 36 are interposed. The expansion valve 35 controls the flow rate of the refrigerant according to the change in the gas temperature at the outlet side of the evaporator 36.

An electric capacity control valve 39 shown in FIG. 2 is interposed on the refrigerant supply passage 38 connecting the discharge chamber 132 and the control pressure chamber 121. The refrigerant supply passage 38 is a passage that supplies the refrigerant in the discharge chamber 132 that is a discharge pressure region to the control pressure chamber 121. The pressure (suction pressure) in the suction chamber 131 acts on the bellows 40 constituting the pressure sensing means 47 in the capacity control valve 39. The suction pressure in the suction chamber 131 reflects the heat load. A valve element 41 is connected to the bellows 40, and the valve element 41 opens and closes a valve hole 42. The atmospheric pressure in the bellows 40 and the spring force of the pressure-sensitive spring 401 constituting the pressure-sensitive means 47 act on the valve body 41 in a direction to open the valve hole 42. Fixed iron core 43 constituting solenoid 43 of displacement control valve 39
1 attracts the movable iron core 433 based on excitation by current supply to the coil 432. That is, the electromagnetic driving force of the solenoid 43 urges the valve body 41 in a direction to close the valve hole 42 against the spring force of the opening urging spring 48. Follower spring 49
Urges the movable iron core 433 toward the fixed iron core 431. The solenoid 43 is controlled by the control computer C1 to supply current.

The control computer C1 supplies current to the solenoid 43 when the air conditioner operation switch 44 is turned on, and stops supplying current when the air conditioner operation switch 44 is turned off. The control computer C1 has a room temperature setting device 4
5 and a room temperature detector 46 are connected in signal. The control computer C1 controls the supply current value to the solenoid 43 based on the target room temperature information set by the room temperature setting unit 45 and the detected room temperature information detected by the room temperature detector 46. The opening / closing state of the valve hole 42, that is, the valve opening is determined by the electromagnetic driving force generated by the solenoid 43,
, The spring force of the opening urging spring 48, and the balance of the urging force of the pressure sensing means 47.
Control is performed to generate a suction pressure corresponding to the current value supplied to the solenoid 43.

When the supply current value is increased, the valve opening decreases, and the amount of refrigerant supplied from the discharge chamber 132 to the control pressure chamber 121 decreases. Since the refrigerant in the control pressure chamber 121 flows out to the suction chamber 131 through the refrigerant extraction passage including the passage 50, the discharge port 221, and the communication port 143, the pressure in the control pressure chamber 121 decreases. Accordingly, the inclination angle of the swash plate 20 increases, and the discharge capacity increases. An increase in the discharge capacity causes a decrease in the suction pressure. When the supply current value is reduced, the valve opening increases, and the amount of refrigerant supplied from the discharge chamber 132 to the control pressure chamber 121 increases. Therefore, the pressure in the control pressure chamber 121 increases, the inclination angle of the swash plate 20 decreases, and the discharge capacity decreases. A decrease in the discharge capacity results in an increase in the suction pressure.

When the value of the current supplied to the solenoid 43 becomes zero, the valve opening is maximized, and as shown in FIG.
Becomes the minimum. When the inclination angle of the swash plate 20 is minimized, the blocking body 22 closes the suction passage 31 and the refrigerant circulation in the external refrigerant circuit 33 stops. This refrigerant circulation stop state is a state in which the heat load reduction operation is stopped.

The minimum inclination angle of the swash plate 20 is slightly larger than 0 °. Since the minimum inclination angle of the swash plate 20 is not 0 °, even when the inclination angle of the swash plate is at a minimum, the cylinder bore 11 can be used.
Discharge from No. 1 to the discharge chamber 132 is performed. The refrigerant discharged from the cylinder bore 111 into the discharge chamber 132 flows into the control pressure chamber 121 through the refrigerant supply passage 38. The refrigerant in the control pressure chamber 121 passes through the passage 50, the pressure release port 221, and the refrigerant extraction path of the port 143, and passes through the suction chamber 131.
To the cylinder bore 111
It is sucked into the inside and discharged to the discharge chamber 132. That is, when the inclination angle of the swash plate is in the minimum state, the discharge chamber 132 which is the discharge pressure region,
Refrigerant supply passage 38, control pressure chamber 121, the refrigerant discharge passage, suction chamber 131 which is a suction pressure region, cylinder bore 1
A circulation passage via 11 is formed in the compressor. A pressure difference occurs between the discharge chamber 132, the control pressure chamber 121, and the suction chamber 131. Therefore, the refrigerant circulates through the circulation passage, and the lubricating oil flowing with the refrigerant lubricates the inside of the compressor.

When the current supply to the solenoid 43 is restarted, the valve opening becomes small, and the pressure in the control pressure chamber 121 decreases. Therefore, the inclination angle of the swash plate 20 increases from the minimum inclination angle. When the inclination angle of the swash plate 20 increases from the minimum inclination angle, the blocking body 22 separates from the valve forming plate 15, and the refrigerant flows from the suction passage 31 into the suction chamber 131. That is, the circulation of the refrigerant in the external refrigerant circuit 33 is restarted.

The control computer C1 performs a buffer current supply start control when the current supply to the capacity control valve 39 is started when the air conditioner operation switch 44 is turned on.
The control computer C1 is provided with an air conditioner operation switch 4
When the supply of current to the capacity control valve 39 is stopped when the switch 4 is turned off, a current supply stop control for buffering is performed.

When the air conditioner operation switch 44 serving as current supply start command means is turned on, a current supply start command signal S1 is output to the control computer C1, as shown in FIG. The control computer C1 serving as the buffer current supply start control means calculates the target room temperature set by the room temperature setter 45 in response to the input of the current supply start command signal S1 and the detected temperature detected by the room temperature detector 46. The designated supply current value Ix for the capacity control valve 39 is determined based on the comparison. Control computer C as supply current value designating means
1 performs buffering current supply start control for gradually increasing the supply current value from zero to the specified supply current value Ix as indicated by the upward slope portion E1 of the curve E in FIG. When the buffer current supply start control is performed, the valve opening of the capacity control valve 39 gradually decreases, and the pressure in the control pressure chamber 121 gradually decreases. With the slow pressure decrease in the control pressure chamber 121, the inclination angle of the swash plate 20 gradually increases from the minimum inclination angle as shown by the upward inclination portion K1 of the curve K in FIG. It increases. When the inclination angle of the swash plate 20 increases from the minimum inclination angle, the refrigerant circulates in the external refrigerant circuit 33, and the suction pressure decreases. The flat part P1 of the curve P in FIG. 6 represents the suction pressure before the air conditioner operation switch 44 is turned on, and the downward slope P2 of the curve P is the swash plate 20.
Represents the fluctuation of the suction pressure due to the gradual increase in the inclination from the minimum inclination.

When the supply current value reaches the designated supply current value Ix, the swash plate 20 moves to the tilt position corresponding to the designated supply current value Ix, and the suction pressure converges to the suction pressure corresponding to the designated supply current value Ix. . Flat portion P of curve P in FIG.
Reference numeral 3 denotes a suction pressure corresponding to the specified supply current value Ix.

When the air conditioner operation switch 44 serving as the current supply stop command means is turned off, as shown in FIG.
The current supply stop command signal S2 is output to the control computer C1. In response to the input of the current supply stop command signal S2, the control computer C1 serving as the buffer current supply stop control means changes the supply current value to the current supply stop command as shown by the downward slope portion E2 of the curve E in FIG. Buffer current supply stop control is performed to gradually reduce the supply current value Iy when the signal S2 is input to the supply current value of zero. When the buffer current supply stop control is performed, the valve opening of the capacity control valve 39 gradually increases, and the pressure in the control pressure chamber 121 gradually increases. As the pressure in the control pressure chamber 121 slowly rises, the inclination angle of the swash plate 20 gradually decreases from the inclination angle at the time of input of the current supply stop command signal S2 as shown by the downward slope K2 of the curve K in FIG. The discharge capacity gradually decreases.
When the inclination angle of the swash plate 20 decreases from the inclination angle at the time of input of the current supply stop command signal S2, the discharge capacity decreases, and the suction pressure increases. A flat portion P4 of the curve P in FIG. 6 represents the suction pressure before the air conditioner operation switch 44 is turned off.
The upward slope portion P5 represents the suction pressure fluctuation due to a gradual decrease in the tilt angle from the tilt angle at the time of input of the current supply stop command signal S2 of the swash plate 20.

When the supply current value becomes zero, the swash plate 20 moves to the minimum inclination position, and the circulation of the refrigerant in the external refrigerant circuit 33 is stopped. Flat portion P6 of curve P in FIG.
Represents the suction pressure after the refrigerant circulation in the external refrigerant circuit 33 is stopped.

The first embodiment in which the above-described variable capacitance operation is performed has the following effects. (1-1) When current supply to the electric capacity control valve 39 is started by turning on the air conditioner operation switch 44, the supply current value is gradually increased from a supply current value of zero to a designated designated supply current value. The buffer current supply start control is performed. The slow increase in the supply current value suppresses a sharp increase in the inclination angle of the swash plate 20. The sharp increase in the inclination angle of the swash plate 20 causes a collision between the rotary support 19 that defines the maximum inclination angle of the swash plate 20 and the swash plate 20, and a collision sound is generated. The gradual increase in the supply current value is set so that the increase in the inclination angle of the swash plate 20 follows the increase in the supply current value. The suppression of such a rapid increase in the inclination angle of the swash plate 20 is as follows.
The overrun of the swash plate 20 from the tilt position corresponding to the specified supply current value is suppressed. When the specified supply current value corresponds to the maximum inclination, the inclination increasing speed at the maximum inclination position of the swash plate 20 is suppressed. As a result, a collision between the rotary support 19 and the swash plate 20 that causes a collision sound is avoided.

(1-2) OF of air conditioner operation switch 44
When the current supply to the electric capacity control valve 39 is stopped by the F operation, the O
Buffer current supply stop control is performed to gradually reduce the supply current value from the specified supply current value immediately before the FF to the supply current value of zero. The slow decrease in the supply current value suppresses a sharp decrease in the inclination angle of the swash plate 20. The sharp decrease in the inclination angle of the swash plate 20 causes a collision between the valve forming plate 15 that defines the minimum inclination angle of the swash plate 20 and the blocking body 22 interlocked with the swash plate 20, and a collision sound is generated. The gradual decrease of the supply current value is determined by the swash plate 20.
Is set so that the decrease in the inclination angle follows the decrease in the supply current value. Such suppression of the rapid decrease in the inclination angle of the swash plate 20 suppresses the inclination decreasing speed at the minimum inclination position of the swash plate 20. Suppression of the inclination decreasing speed at the minimum inclination position of the swash plate 20 avoids collision between the valve forming plate 15 and the blocking body 22 that causes collision sound.

Next, a second embodiment shown in FIGS. 7 and 8 will be described. The same components as those in the first embodiment are denoted by the same reference numerals. In this embodiment, the suction pressure in the suction chamber 131 is detected by the pressure detector 51, and the control pressure in the control pressure chamber 121 is detected by the pressure detector 52. . Double pressure detector 5
1, 52 send the detection information to the control computer C2. The control computer C2 stores a (suction pressure-supply current value) map and a (control pressure-supply current value) map.
The control computer C2 uses the (suction pressure-supply current value) map and the pressure detector 51 when starting the current supply to the capacity control valve 39 when the air conditioner operation switch 44 is turned on.
Control for starting the supply of current for buffering using the pressure detection information obtained from. When the current supply to the capacity control valve 39 is stopped when the air conditioner operation switch 44 is turned off, the control computer C2 reads the (control pressure-supply current value) map and the pressure detection information obtained from the pressure detector 52. The used buffer current supply stop control is performed.

When the air conditioner operation switch 44 serving as the current supply start command means is turned on, a current supply start command signal S1 is output to the control computer C2 as shown in FIG. The control computer C2, which serves as a buffer current supply start control unit, calculates the target room temperature set by the room temperature setter 45 in response to the input of the current supply start command signal S1 and the detected temperature detected by the room temperature detector 46. The designated supply current value Ix for the capacity control valve 39 is determined based on the comparison. The control computer C2 serving as the supply current value designating means uses the designated supply current value Ix, the detected pressure obtained from the pressure detector 51, and the increased jump limit supply current value Iz based on the (suction pressure-supply current value) map. Find out. The (suction pressure-supply current value) map is a map for obtaining the increase jump limit supply current value Iz using the suction pressure and the supply current value as variables.

The control computer C2 discontinuously switches the supply current value from zero to the increasing jump limit supply current value Iz as indicated by the vertical line D1 of the curve D in FIG. 8, and then indicates the rising slope D2. As described above, the buffer current supply start control for gradually increasing the supply current value from the increase jump limit supply current value Iz to the designated supply current value Ix is performed. When the buffer current supply start control is performed, the valve opening degree of the capacity control valve 39 instantaneously changes to the valve opening degree corresponding to the increase leaping limit supply current value Iz, and then gradually decreases. The pressure in the chamber 121 gradually decreases in a state where it follows the slow increase of the supply current value from the increase jump limit supply current value Iz. With the slow pressure drop in the control pressure chamber 121, the swash plate 2
The inclination angle of 0 gradually increases from the minimum inclination angle as indicated by the upward inclination portion H1 of the curve H in FIG. 8, and the discharge capacity gradually increases. The slow inclination of the swash plate 20 is performed in such a manner as to follow a slow decrease in the supply current value from the increase jump limit supply current value Iz. When the inclination angle of the swash plate 20 increases from the minimum inclination angle, the refrigerant circulates in the external refrigerant circuit 33, and the suction pressure decreases. The flat portion Q1 of the curve Q in FIG. 8 represents the suction pressure before the air conditioner operation switch 44 is turned on, and the downward slope Q2 of the curve Q is accompanied by a gradual increase in the inclination of the swash plate 20 from the minimum inclination. Indicates suction pressure fluctuation.

When the supply current value reaches the designated supply current value Ix, the swash plate 20 moves to the tilt position corresponding to the designated supply current value Ix, and the suction pressure converges to the suction pressure corresponding to the designated supply current value Ix. . Flat portion Q of curve Q in FIG.
Reference numeral 3 denotes a suction pressure corresponding to the specified supply current value Ix.

When the air conditioner operation switch 44 is turned off, a current supply stop command signal S2 is output to the control computer C2 as shown in FIG. In response to the input of the current supply stop command signal S2, the control computer C2 serving as the buffering current supply stop control means responds to the input of the current supply stop command signal S2, the designated supply current value when the air conditioner operation switch 44 is turned off, and the detection control obtained from the pressure detector 52 Based on the pressure and the (control pressure-supply current value) map, a decrease leap limit supply current value Iw is determined. The (control pressure-supply current value) map is a map for obtaining the decrease jump limit supply current value Iw using the control pressure and the supply current value as variables. The control computer C2 changes the supply current value to the designated supply current value Iy immediately before the air conditioner operation switch 44 is turned off, as indicated by the vertical line D3 of the curve D in FIG.
, The control is discontinuously switched to the reduced jump limit supply current value Iw, and then the buffer current supply stop control is performed to gradually reduce the supply current value from the reduced jump limit supply current value Iw to zero as indicated by the downward slope D4. . When the buffer current supply stop control is performed, the valve opening of the capacity control valve 39 instantaneously changes to the valve opening corresponding to the decrease jump limit supply current value Iw, and then gradually increases. The pressure in the chamber 121 gradually increases in such a state as to follow a gradual decrease in the supply current value from the decrease jump limit supply current value Iw. As the pressure in the control pressure chamber 121 slowly rises, the inclination angle of the swash plate 20 gradually decreases from the inclination angle at the time of input of the current supply stop command signal S2 as shown by the downward slope H2 of the curve H in FIG. I will do it. The inclination angle of the swash plate 20 is determined by the current supply stop command signal S.
When the inclination angle is decreased from the input angle of 2, the discharge capacity decreases, and the suction pressure increases. A flat portion Q4 of the curve Q in FIG. 8 represents the suction pressure before the air conditioner operation switch 44 is turned off, and an upwardly sloping portion Q5 of the curve Q when the current supply stop command signal S2 of the swash plate 20 is input. It shows the suction pressure fluctuation accompanying the gradual decrease of the inclination from the inclination.

When the supply current value becomes zero, the swash plate 20 moves to the minimum inclination position, and the circulation of the refrigerant in the external refrigerant circuit 33 is stopped. Flat portion Q6 of curve Q in FIG.
Represents the suction pressure after the refrigerant circulation in the external refrigerant circuit 33 is stopped.

The following effects can be obtained in the second embodiment. (2-1) When the current supply to the electric capacity control valve 39 is started by turning on the air conditioner operation switch 44, the control computer C2 constituting the increase jump limit supply current value specifying means together with the pressure detector 51 detects the current. Specify the increase jump limit supply current value according to the suction pressure. And
The control computer C2 increases the supply current value discontinuously from zero to the increase jump limit supply current value Iz, and then gradually increases the supply current value from the increase jump limit supply current value Iz to the designated supply current value. Control for starting the supply of the buffer current. The increased jump limit supply current value Iz is determined by the swash plate 20.
Limit value of the amount of discontinuous increase of the supply current value from zero so as not to cause collision with the rotating support 19 and depends on the suction pressure. That is, when the supply current value is discontinuously increased from zero to a value higher than the increase jump limit supply current value Iz corresponding to the detected suction pressure, the swash plate 20 is rotated by the rotating support 1.
Collision 9 generates a collision sound. When the supply current value is discontinuously increased from zero to the increase jump limit supply current value Iz, the inclination of the swash plate 20 from the minimum inclination is quickly increased without causing a collision sound, and the capacity is restored. It is done promptly.

(2-2) OF of air conditioner operation switch 44
When the current supply to the electric capacity control valve 39 is stopped by the F operation, the control computer C which constitutes the decrease jump limit supply current value designating means together with the pressure detector 52.
Numeral 2 designates a decrease jump limit supply current value corresponding to the detection control pressure. Then, the control computer C2 discontinuously reduces the supply current value from the specified supply current value immediately before the air conditioner operation switch 44 is turned off to the decrease jump limit supply current value Iw, and then supplies the supply current value from the decrease jump limit supply current value Iw. Buffer current supply stop control is performed to gradually reduce the supply current value to a current value of zero. The decrease jump limit supply current value Iw is a limit value of a discontinuous decrease amount from the designated supply current value Iy so as not to cause a collision between the interrupter 22 and the valve forming plate 15, and depends on the detection control pressure. You. That is, when the supply current value is discontinuously reduced from the designated supply current value Iy to a value lower than the decrease jump limit supply current value Iw corresponding to the detected control pressure, the shutoff 22 collides with the valve forming plate 15. A collision sound is generated. When the supply current value is discontinuously decreased from the specified supply current value Iy to the leaping limit supply current value Iw, the transition of the swash plate 20 to the minimum inclination position is performed promptly without causing a collision sound. .

Next, a third embodiment shown in FIGS. 9 and 10 will be described. The same components as those in the first embodiment are denoted by the same reference numerals. In this embodiment, when the solenoid 531 of the electric capacity control valve 53 is excited, the valve body 532 closes the valve hole 533, and the swash plate 20 shifts to the maximum tilt position. When the solenoid 531 is demagnetized, the valve body 532 moves to the maximum valve opening position, and the swash plate 20 moves to the minimum inclination position. When the air conditioner operation switch 44 serving as the current supply start command means and the current supply stop command means is turned on, the control computer C3 excites the solenoid 531. When the air conditioner operation switch 44 is turned off while the solenoid 531 is energized, the control computer C3 demagnetizes the solenoid 531. Air conditioner operation switch 44 is O
In the N state, when the detected temperature obtained by the room temperature detector 46 falls below the target room temperature set by the room temperature setting unit 45, the control computer C3 commands the solenoid 531 to demagnetize. When the detected temperature exceeds the target room temperature, the control computer C3 commands the solenoid 531 to be excited. The room temperature detector 46 and the control computer C3 constitute current supply start command means and current supply stop command means.

When the solenoid 531 is to be excited, the control computer C3 sets the upward slope F1 of the curve F in FIG.
The buffer current supply start control shown in FIG. The maximum value of the supply current value is the specified supply current value. The signal S3 indicates a current supply start command when the air conditioner operation switch 44 is turned on or when the detected temperature exceeds the target room temperature. The upward slope G1 of the curve G represents an increase in the inclination angle of the swash plate 20 with an increase in the supply current value, and the downward slope R1 of the curve R represents a decrease in the suction pressure with an increase in the inclination angle of the swash plate 20.

When the solenoid 531 is to be demagnetized, the control computer C3 executes the downward slope F2 of the curve F in FIG.
The control for stopping the supply of current for buffering is performed. The signal S4 is
This indicates a current supply stop command when the air conditioner operation switch 44 is turned off or when the detected temperature falls below the target room temperature. A downward slope G2 of the curve G represents a decrease in the inclination of the swash plate 20 with a decrease in the supply current value, and an upward slope R2 of the curve R.
Represents an increase in suction pressure as the inclination angle of the swash plate 20 decreases.

Also in this embodiment, the inclination increasing speed of the swash plate 20 at the maximum inclination position of the swash plate 20 is suppressed, and the collision between the swash plate 20 and the rotary support 19 is suppressed.
Further, the inclination decreasing speed of the swash plate 20 at the minimum inclination position of the swash plate 20 is suppressed, and the collision between the blocking body 22 and the valve forming plate 15 is suppressed.

In the present invention, the following embodiments are also possible. (1) In the first embodiment, at the start of the current supply, the supply current value is continuously increased from zero to the maximum value or near the maximum value so as to suppress the inclination increasing speed at the maximum inclination position of the swash plate 20. Afterwards, it should be continuously reduced to the specified supply current value. By doing so, the capacity recovery is quickened. (2) The present invention is applied to a variable displacement compressor in which a displacement control valve is interposed on a passage for extracting refrigerant from a control pressure chamber to a suction pressure region. (3) Duty ratio control of the supply current value. In this case, the average supply current value per unit time is regarded as the supply current value. (4) The present invention is applied to a variable displacement compressor with a clutch that transmits a driving force from an external drive source to a rotating shaft via a clutch.

[0057]

As described in detail above, when the current supply to the electric capacity control valve is started, the inclination of the swash plate at the maximum inclination position is increased until the supply of the specified supply current value is started. In the invention in which the buffer current supply start control for suppressing the speed is performed, unnecessary arrival of the swash plate at the maximum tilt position is avoided to avoid collision noise, and furthermore, the swash plate is moved to the maximum tilt position. An excellent effect of being able to suppress the collision sound when the vehicle comes to the vehicle.

When the current supply to the electric displacement control valve is stopped, a buffer current supply stop control for suppressing the inclination decreasing speed at the minimum inclination position of the swash plate as a process until the supply current value becomes zero. The present invention has an excellent effect that the collision sound when the swash plate comes to the minimum tilt position can be suppressed.

[Brief description of the drawings]

FIG. 1 is a side sectional view of an entire compressor according to a first embodiment.

FIG. 2 is a longitudinal sectional view of the electric capacity control valve 39.

FIG. 3 is a sectional side view of a main part in which a swash plate tilt angle is in a minimum state.

FIG. 4 is a sectional view taken along line AA of FIG. 1;

FIG. 5 is a sectional view taken along line BB of FIG. 1;

FIG. 6 is a graph showing a relationship between a supply current value, a swash plate inclination angle, and a suction pressure.

FIG. 7 is a side sectional view of the entire compressor showing a second embodiment.

FIG. 8 is a graph showing a relationship between a supply current value, a swash plate inclination angle, and a suction pressure.

FIG. 9 is a side sectional view of the entire compressor showing a third embodiment.

FIG. 10 is a graph showing a relationship between a supply current value, a swash plate inclination angle, and a suction pressure.

[Explanation of symbols]

121: a control pressure chamber; 131: a suction chamber serving as a suction pressure area;
132: discharge chamber serving as a discharge pressure region, 18: rotating shaft, 20
... swash plate, 38 ... refrigerant supply passage, 39 ... electric capacity control valve, 44 ... air conditioner operation switch serving as current supply start command means and current supply stop command means, C1 buffer current supply start control means, buffer A control computer serving as current supply stop control means and supply current value designating means; C2... Buffer current supply start control means; buffer current supply stop control means;
Control computer serving as supply current value designating means, increase jump limit supply current value designating means, and decrease jump limit supply current value designating means; C3 ... control computer serving as buffer current supply start control means and buffer current supply stop control means .

Continued on the front page F term (reference) 3H045 AA04 AA10 AA12 AA27 BA38 CA02 CA21 CA24 DA25 DA42 DA50 EA13 EA16 EA26 EA33 3H076 AA06 BB01 CC12 CC39 CC84

Claims (12)

[Claims] 1. A swash plate accommodated in a control pressure chamber so as to rotate integrally with a rotation shaft and variably inclined with respect to the rotation shaft, and a piston performing reciprocating operation according to the inclination of the swash plate. And supplying the refrigerant from the discharge pressure area to the control pressure chamber, extracting the refrigerant from the control pressure chamber to the suction pressure area, and on the refrigerant supply passage from the discharge pressure area to the control pressure chamber or the control pressure. An electric capacity control valve is interposed on a refrigerant discharge passage from the chamber to the suction pressure area, and a supply current value to the electric capacity control valve is controlled to supply the refrigerant from the discharge pressure area to the control pressure chamber. Alternatively, in the variable displacement compressor, which controls a refrigerant withdrawal amount from the control pressure chamber to the suction pressure region and controls a tilt angle of the swash plate based on control of a pressure in the control pressure chamber, Current supply to valve When starting the supply of the specified supply current value, in the variable displacement compressor that performs a buffer current supply start control for suppressing the inclination increasing speed at the maximum inclination position of the swash plate as a process until the supply of the specified supply current value is started. Capacity control method. 2. The buffer current supply start control increases a supply current value from a supply current value of zero to a designated supply current value, and the buffer current supply start control includes a step of changing the supply current value from zero to the specified supply current value. 2. The capacity control method according to claim 1, further comprising a current increase supply state in which the supply current value is gradually increased in at least a part of the range up to the specified supply current value. 3. The buffer current supply start control includes: a supply current value switching state in which the supply current value is discontinuously switched from a supply current value of zero to an increase jump limit supply current value that does not reach the designated supply current value; 3. The capacity control method according to claim 2, further comprising a current increase supply state in which the supply current value is gradually increased from the increase jump limit supply current value to the designated supply current value. 4. A swash plate accommodated in a control pressure chamber so as to rotate integrally with a rotation shaft and variably inclined with respect to the rotation shaft, and a piston performing reciprocating operation according to the inclination angle of the swash plate. And supplying the refrigerant from the discharge pressure area to the control pressure chamber, extracting the refrigerant from the control pressure chamber to the suction pressure area, and on the refrigerant supply passage from the discharge pressure area to the control pressure chamber or the control pressure. An electric capacity control valve is interposed on a refrigerant discharge passage from the chamber to the suction pressure area, and a supply current value to the electric capacity control valve is controlled to supply the refrigerant from the discharge pressure area to the control pressure chamber. Alternatively, in the variable displacement compressor, which controls a refrigerant withdrawal amount from the control pressure chamber to the suction pressure region and controls a tilt angle of the swash plate based on control of a pressure in the control pressure chamber, Current supply to valve When stopping the supply, the capacity control method in the variable displacement compressor that performs the buffer current supply stop control for suppressing the inclination decreasing speed at the minimum inclination position of the swash plate as a process until the supply current value becomes zero. . 5. The buffer current supply stop control decreases a supply current value from a designated supply current value to a supply current value of zero, and the buffer current supply stop control includes a step of reducing the supply current value from the designated supply current value. 5. The capacity control method for a variable displacement compressor according to claim 4, including a current decreasing supply state in which the supply current value is gradually reduced in at least a part of the range up to the supply current value of zero. 6. The buffer current supply stop control includes a supply current value switching state in which the supply current value is discontinuously switched from the specified supply current value to a reduced jump limit supply current value that does not reach the specified supply current value. 6. The capacity control method for a variable displacement compressor according to claim 5, further comprising: a current decreasing supply state in which a supply current value is gradually reduced from the decrease jump limit supply current value to a supply current value of zero. 7. A swash plate accommodated in a control pressure chamber so as to rotate integrally with a rotation shaft and variably inclined with respect to the rotation shaft, and a piston performing reciprocating operation according to the inclination angle of the swash plate. And supplying the refrigerant from the discharge pressure area to the control pressure chamber, extracting the refrigerant from the control pressure chamber to the suction pressure area, and on the refrigerant supply passage from the discharge pressure area to the control pressure chamber or the control pressure. An electric capacity control valve is interposed on a refrigerant discharge passage from the chamber to the suction pressure area, and a supply current value to the electric capacity control valve is controlled to supply the refrigerant from the discharge pressure area to the control pressure chamber. Alternatively, in the variable displacement compressor, which controls a refrigerant withdrawal amount from the control pressure chamber to the suction pressure region and controls a tilt angle of the swash plate based on control of a pressure in the control pressure chamber, Current supply to valve Current supply start command means for instructing the start of the swash plate, and buffer current supply start control means for performing a buffer current supply start control for suppressing a tilt increasing speed at a maximum tilt position of the swash plate; The capacity current supply start control means is a capacity control device for a variable displacement compressor that performs the buffer current supply start control based on a current supply start command of the current supply start command means. 8. A supply current value designating means for designating a supply current value, wherein said buffering current supply start control means supplies from a supply current value of zero to a designated supply current value designated by said supply current value designation means. 8. The variable displacement compressor according to claim 7, wherein a current supply start control for increasing a current value and gradually increasing a supply current value in at least a part of a range from a supply current value of zero to the designated supply current value is performed. In the capacity control device. 9. An increase jump limit supply current value designating means for designating an increase jump limit supply current value that does not reach the designated supply current value, wherein the buffer current supply start control means includes a step of increasing the supply current value from zero. The supply current value is discontinuously switched to the increase jump limit supply current value designated by the jump limit supply current value designation means, and the supply current value is gradually increased from the increase jump limit supply current value to the designated supply current value. 9. The displacement control device for a variable displacement compressor according to claim 8, wherein the current supply start control is performed. 10. A swash plate housed in a control pressure chamber so as to rotate integrally with a rotation shaft and variably inclined with respect to the rotation shaft, and a piston performing reciprocating operation according to the inclination angle of the swash plate. And supplying the refrigerant from the discharge pressure area to the control pressure chamber, extracting the refrigerant from the control pressure chamber to the suction pressure area, and on the refrigerant supply passage from the discharge pressure area to the control pressure chamber or the control pressure. An electric capacity control valve is interposed on a refrigerant discharge passage from the chamber to the suction pressure area, and a supply current value to the electric capacity control valve is controlled to supply the refrigerant from the discharge pressure area to the control pressure chamber. Alternatively, in the variable displacement compressor, which controls a refrigerant withdrawal amount from the control pressure chamber to the suction pressure region and controls a tilt angle of the swash plate based on control of a pressure in the control pressure chamber, Current supply to valve Current supply stop command means for instructing the stop of the supply, and buffer current supply stop control means for performing buffer current supply stop control for suppressing the inclination decreasing speed at the minimum inclination position of the swash plate, The buffer current supply stop control means is a displacement control device for a variable displacement compressor that performs the buffer current supply stop control based on a current supply stop command of the current supply stop command means. 11. A supply current value designating means for designating a supply current value, wherein said buffering current supply stop control means supplies from a designated supply current value designated by said supply current value designation means to a supply current value of zero. 11. The variable displacement compressor according to claim 10, wherein current supply stop control is performed to reduce a current value and gradually decrease a supply current value in at least a part of a range from the designated supply current value to a supply current value of zero. In the capacity control device. 12. A system according to claim 11, further comprising a decreasing jump limit supply current value designating means for designating a decreasing jump limit supply current value, wherein said buffer current supply stop control means determines said decreasing jump limit supply current value from said designated supply current value. A current supply stop control for discontinuously switching a supply current value to a decrease jump limit supply current value specified by the above, and gradually decreasing the supply current value from the decrease jump limit supply current value to a supply current value of zero. 12. A displacement control device for a variable displacement compressor according to claim 11.