JPS63232017A - External control device for variable displacement compressor - Google Patents

Abstract

PURPOSE:To improve the constant speed running performance of a car as automatic control performed by a compressor on its internal capacity is utilized by forcibly controlling the capacity of a variable displacement compressor to the maximum or the minimum according to a command issued from an external constant speed running control device. CONSTITUTION:During the normal operation of a car, the bypass quantity of a refrigerant toward an inlet side in the compression stroke of a variable displacement compressor 2 forming an air conditioning device is adjusted by a variable capacity mechanism 50 to perform cooling operation effectively. On the other hand, when a command signal is output from a constant speed running control device 101 during car running, a capacity control means 110 controls a capacity setting mechanism SV. At this time, a bypass passage 39 is fully opened in an accelerating state, namely the discharge capacity of the compressor 2 is set to the minimum, and the bypass passage 39 is totally closed in a decelerating state, namely the discharge capacity of the compressor 2 is set to the maximum. The running performance of the car can therefore be improved as automatic control performed by the compressor 2 on its internal capacity is utilized.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an air conditioner installed in a vehicle, and in particular to a control system that externally controls a variable capacity compressor called a variable internal capacity compressor. be.

(Prior Art) Conventionally, this type of automatic heavy-duty air conditioner cools gas refrigerant discharged from a compressor driven and connected to an on-vehicle engine via an electromagnetic clutch and a cough compressor by heat exchange with air. It is equipped with a condenser ('II condenser) that condenses the liquid refrigerant that has passed through the condenser, and an evaporator that cools the interior of the vehicle with the heat of vaporization. It is generally well known that when the evaporation temperature of the refrigerant falls below a predetermined temperature, this is detected by a 70 stroke switch and the drive of the compressor is stopped by turning off the FI 19 clutch mechanism, and is widely used in actual vehicles. is equipped with.

In other words, when the engine speed increases, the amount of refrigerant discharged from the compressor driven by the engine increases and a large amount of refrigerant circulates through the refrigerant circuit, increasing the capacity of the compressor. Since the heat load is approximately constant, there is a surplus of capacity, and in order to eliminate this surplus, the drive of the compressor is stopped.

However, in this case, from the perspective of reducing the driving force of the engine to drive the compressor and improving EER (energy consumption efficiency), it is preferable to stop the compressor operation and then recondense it. It is preferable to continue operation with the capacity lower than in the steady state. For example, looking at the dependence of each compensator on the coefficient of performance of a compressor, condenser, and evaporator, the smaller the capacity of the compressor, the lower the work capacity of the compressor itself. The contribution rate becomes large and the overall coefficient of performance increases. In other words, although the compressor's work capacity has decreased, the overall enthalpy remains the same, resulting in an increase in EER.

Therefore, as a compressor that satisfies such requirements, a variable internal capacity compressor has been proposed as disclosed in Japanese Patent Application Laid-Open No. 60-261721. When the compressor capacity becomes excessive, a portion of the refrigerant sucked into the compressor body is bypassed during the compression stroke and returned to the suction side, thereby reducing the compressor capacity to reduce the heat load inside the vehicle. It is designed to automatically control the corresponding ability.

(Problem to be Solved by the Invention) However, on the other hand, in the air conditioner of this proposal that incorporates a variable type compressor, the capacity of the compressor is automatically controlled to the capacity that corresponds to the heat load inside the vehicle. Therefore, the following problems arise.

In other words, the constant speed driving system ti! automatically maintains the driving speed so that it converges to the speed value set by the driver. In a vehicle equipped with an I device, it is preferable to respond to changes in engine load as much as possible by changing the driving load of the compressor of the air conditioner when the engine load changes depending on the acceleration state or deceleration state of the vehicle. . In other words, by reducing the drive load on the compressor during acceleration, the reduction in engine output required for driving is minimized, and on the other hand, during deceleration, the compressor load is increased to increase the engine load and apply so-called engine braking. This is because the target speed can be reached quickly.

However, when the variable internal capacity type compressor is used, it has the ability to adjust the operating capacity only in response to room temperature conditions, and the compressor load cannot be changed in response to changes in engine load. Therefore, there is a problem in that the driving performance of the vehicle during constant speed driving deteriorates.

The present invention has been made in view of the above, and its purpose is to not only automatically control the internal capacity of a variable internal capacity compressor as described above, but also to control the capacity using an external regulator. The object of the present invention is to improve the constant-speed running performance of a vehicle equipped with a constant-speed running control device by forcibly controlling the capacity to a maximum or minimum capacity according to a command from the speed running control device.

(Means for Solving the Problems) In order to achieve this object, the solution of the present invention is to reduce or accelerate the vehicle when the traveling speed of the vehicle changes in response to the command signal of the constant speed traveling control device. Accordingly, the internal capacity control of the compressor is temporarily prohibited, and the capacity is held fixed at the maximum or minimum capacity, respectively.

Specifically, as shown in FIG. 1, in the air conditioner 1 for personal vehicle width, there is a suction boat 21 that sucks refrigerant, and the refrigerant is sucked from the suction boat 21 and undergoes a compression stroke. A discharge boat 22 that discharges refrigerant, a bypass passage 39 that bypasses the refrigerant in the compression stroke to the suction side, and a variable capacity u! that controls opening and closing of the bypass passage 39 according to the suction pressure of the refrigerant. jl! The subject is an external control device that externally controls the variable capacity 0 compressor 2 of a vehicle air iPl device having a vehicle air iPl device.

The compressor 2 includes the bypass passage 3.
A capacity setting mechanism S2 is provided for driving the variable capacity ff1ll bucket 50 so that the refrigerant discharge capacity is set to the maximum or minimum so that the refrigerant discharge capacity is set to the maximum or minimum.

Further, capacity control is performed to operate the capacity setting assv so that the compressor 2 is set to the maximum capacity or the minimum capacity in accordance with the shuttle of the command signal of the constant speed running control device 101 that maintains the running speed of the vehicle at the set value. The configuration is such that means 110 is provided.

(Function) With the above configuration, in the present invention, during normal operation of the vehicle, the variable capacity mechanism 50 adjusts the bypass flow of refrigerant to the suction side in the compression stroke of the compressor 2 of the air conditioner 1 of the vehicle, Cooling operation is performed with high efficiency.

When the need for acceleration or deceleration arises while the vehicle is running, and a command signal is output from the constant speed cruise control device 101, the capacity control means 110 forcibly fully opens the bypass passage 39 in the acceleration state. In other words, the displacement setting machine msv is driven to set the discharge capacity of the compressor 2 to the minimum, while in the deceleration state, the bypass passage 39 is forcibly fully opened, that is, to set the discharge capacity of the compressor 2 to the maximum.

Therefore, during normal driving, the automatic 1liI11p internal capacity adjustment by the variable internal capacity type compressor 2 is utilized, and when the vehicle accelerates or decelerates, the capacity control means 108 operates the capacity setting tiII4sv to drive the vehicle at a constant speed. By forcibly controlling the capacity of the compressor 2 to the maximum capacity or the minimum capacity according to the type of command signal from the control device @101, it is possible to function to compensate for the output required by the engine 12 at that time. , the driving performance of the vehicle can be improved.

(First Embodiment) Hereinafter, an embodiment of the present invention will be described based on the drawings from FIG. 2 onwards.

FIG. 2 shows the overall configuration of the first embodiment of the present invention,
1 is the sky equipped to my vJii! i! The air conditioner 1 includes a compressor 2 which is drive-connected to an on-vehicle engine 12 via an electromagnetic clutch [13 and a transmission belt 14], and a compressor 2 which is disposed at the front end of the engine room of the vehicle body, and which is connected to a vehicle engine 12 through an electromagnetic clutch [13 and a transmission belt 14]. A condenser 3 that cools a gas refrigerant and condenses it into a liquid refrigerant through heat exchange, a receiver tank 4 that stores the liquid refrigerant, and a liquid refrigerant that is decompressed to a pressure suitable for evaporation and expanded to maintain a constant degree of superheating of the refrigerant. It is equipped with an expansion pulp 5, which is a temperature-type automatic expansion valve to be controlled, and an evaporator 6, which is placed in the vehicle interior and which evaporates liquid refrigerant and cools the air in the vehicle interior with the heat of vaporization. A refrigerant circuit 8 is constructed by connecting the refrigerant pipes 6 and 6 with a refrigerant pipe 7.

Note that 9 is a moisture sensing tube for the expansion pulp 5 attached to the refrigerant pipe 7 returning from the evaporator 6 to the compressor. Further, 11 is a fan attached to the evaporator 6.

The compressor 2 is a vane type variable capacity compressor. The basic structure of this variable capacity compressor 2 is the same as that of a normal vane type compressor. That is, the main body 20 of this compressor 2 is
As shown in enlarged detail in FIG. 3, there is a ring-shaped side housing 23, a front panel which is airtightly joined to the front and rear surfaces of the side housing 23, and which forms a cylindrical working chamber 24 inside the side housing 23. rear housing 25
．． 26, a cylindrical rotor 27 rotatably fitted in the working chamber 24 of the side housing 23 so as to be offset from the center of the working chamber 24;
The front housing 25 is provided with a pair of through vanes 28, 28 which are supported so as to be freely protrusive and retractable from the outer periphery thereof, and whose ends slide into sliding contact with the inner peripheral wall of the working chamber 24 to partition the working chamber 24. A suction boat 21 that sucks refrigerant into the working chamber 24, and a suction air 29 that communicates with the suction boat 21.
is being formed. In addition, the side housing 23 has the above-mentioned suction bow! - A discharge boat 22 that discharges refrigerant that has been sucked in from the rear housing 21 and has undergone a compression stroke is connected to the rear housing 26.
has a discharge chamber (not shown) communicating with the discharge boat 22.
are formed respectively. Further, the rotating shaft 31 of the rotor 27 is connected to the electromagnetic clutch mechanism 13, and when the electromagnetic clutch mechanism 13 is turned on, the engine 12
The rotor 27 is rotationally driven by the output of
The gas refrigerant sucked from the suction boat 21 of the side housing 23 is compressed by gradually reducing the volume of the portion of the working chamber 24 in the side housing 23 partitioned by the vanes 2B and 28 as the engine rotates. The liquid is discharged from a discharge boat 22.

In this basic configuration, a spool valve 3 is provided in the front housing 25 of the compressor main body 20.
2 is provided. Further, a pressure girder 40 consisting of a needle valve is attached to the lower part of both the side housing 23 and the rear housing 26.

As shown in FIG. 4, the spool valve 32 includes a conical valve housing 33, and is slidably fitted into the valve housing 33, and has a spring chamber 35 and a pressurizing chamber 36 inside the housing 33. The pressurized chamber 36 includes a boat 33a of the valve housing 33 and a communication passage 37 connected to the boat 33a.
is passed through a predetermined gap between the front housing 25 and the side housing 23 in the compressor body 20, and the internal pressure is set to approximately the middle pressure between the suction pressure and the discharge pressure of the gas refrigerant. has been done. Further, a spring 38 that urges the valve body 34 toward the pressurizing chamber 36 is compressed in the spring chamber 35, and the spring chamber 35 communicates with the suction chamber 29 in the front housing 25 through the boat 33b. has been done. Further, the valve housing 33 has four bypass holes 39a to 39b in the middle part of the sliding range of the valve body 34 inside thereof, with the bypass holes 39a and 39b facing each other in the direction of the center line of the housing 33, and bypass holes 39a and 39b. Holes 39a, 39a
Bypass holes 39a, 3 are arranged in series in the center line direction of the housing 33 and are opened on one side of the housing 33 (on the right side in FIG. 3).
Reference numeral 9a denotes a bypass hole 39b of a cello (on the left side) in a portion corresponding to the middle of the refrigerant compression stroke in the working chamber 24.

39b communicate with the suction chamber 29, and bypass holes 39 facing each other in the diametrical direction of the housing 33
a, 39b and both bypass holes 39a.

39b and a part of the spring chamber 35 located between the
Bypass passages 39 and 39 are configured to allow the refrigerant to pass through two suction chambers (on the suction side) during the compression stroke of the refrigerant compressed in the working chamber 24. Then, the urging force due to the intermediate pressure in the pressurizing chamber 36 against the valve body 34 increases the refrigerant suction pressure in the spring chamber 35 to the spring 38 inside the spring chamber 35.
When the urging force is greater than the spring force added, the valve body 3
By moving the valve body 34 downward in FIG. 4, the bypass holes 39a to 39b are closed and the bypass passage 39 is closed. On the other hand, when the valve body 34 is moved upward in the same figure, the bypass hole 39 is closed. By opening 39a and 39b, the bypass passage 39 is opened.

On the other hand, the pressure regulator 40 has two pressure chambers 42.4, a first and a second pressure chamber, communicating through a valve port 41.
3 is formed inside, a valve body 45 is fitted into the valve housing 44 so that the valve port 41 can be opened and closed, and a second pressure chamber 4 of the valve housing 44 is provided.
3 and a diaphragm 46 that partitions the second pressure chamber 43 into a suction pressure chamber 43a and an atmospheric pressure air 43b, and the diaphragm 46 is connected to the valve body through an Orad 4f. 45, and a diaphragm 46 is connected to the atmospheric pressure chamber 43b in the direction of the valve body 45 (the direction in which the valve body 45 communicates with both the first and second pressure chambers 42, 43). A spring 48 that biases the body is compressed. The first pressure chamber 42 is connected to the communication passage 37 (
Front housing 25 in compressor body 20
and the side housing 23) through a communication passage 49, and the suction pressure air 43a in the second pressure chamber 43 is communicated with the suction chamber 29. 43b is open to the atmosphere, and the biasing force due to the refrigerant suction pressure in the suction pressure chamber 43a against the diaphragm 46 is greater than the biasing force obtained by adding the spring force of the spring 48 inside the atmospheric pressure to the atmospheric pressure in the atmospheric pressure ¥43b. Sometimes, the diaphragm 46 is moved downward in FIG. 4 to close the valve port 41 with the valve body 45 integrated with the diaphragm 46, and to cut off communication between the first pressure chamber 42 and the suction chamber 29. , on the other hand, when it is small, the diaphragm 46 is moved upward in the figure to open the valve port 41 and the first pressure chamber 4 is opened.
2 and a suction chamber 29 are communicated with each other. Therefore, the spool valve 32 and the pressure regulator 40 automatically control the refrigerant suction pressure of the compressor main body 20 to keep it substantially constant, and when the rotation speed (engine speed) of the compressor 2 is low and its capacity is low, By closing the pressure regulator 40 and closing the bypass passage 39 by increasing the pressure inside the pressurizing chamber 36 of the spool valve 32, the capacity of the compressor 2 is maintained at the maximum capacity, and the rotation speed of the compressor 2 is increased. When its capacity increases, the suction chamber 2
9, the pressure regulator 4° is closed, and the spool valve 3 is closed due to the pressure regulator 4° being closed.
2, the pressure inside the pressurizing chamber 36 is lowered, and the valve body 3
4 upward in the figure to open the bypass passage 39 and bypass the gas refrigerant internally, the capacity of the compressor 2 is reduced in accordance with the increase in its rotation speed, that is, the heat load in the middle chamber is reduced. Also, when the capacity of the compressor 2 increases, the variable capacity ff1ll1150 is configured to eliminate the excess capacity.

Further, as a feature of the present invention, as shown in FIG. 4, the first pressure chamber 42 of the pressure regulator 40 is
7 and the suction chamber 29 are further connected through a communication passage 5.1 so that the refrigerant can flow therethrough, and a normally closed solenoid valve S■ for opening and closing the communication passage 51 is disposed in the communication passage 5.1. When the solenoid valve SV is closed, the variable volume ff1I is
! While the I mechanism 50 is activated to bring the compressor 2 into an internal control state, when the solenoid valve SV is opened, the suction chamber 29
The internal pressure is made equal to the intermediate pressure, and the valve element 34 of the spool valve 32 is positioned at the upper end position as shown in the figure by the biasing force of the spring 35, and the bypass passage 39 is kept fully open to maximize the refrigerant bypass flow. The capacity of the compressor 2 is set to the minimum capacity by holding the capacity at the minimum capacity. In other words, the electromagnetic valve S
It functions as a minimum capacity setting mechanism that drives the refrigerant discharge capacity 50 to set the refrigerant discharge capacity to the minimum.

In addition, in FIG. 4, 52 is an orifice for relaxing the rapid flow of the refrigerant.

As shown in FIG. 2, a control unit 100 is disposed outside the compressor 2 to control the opening and closing of the solenoid valve S from the outside. and a constant control system that variably controls the shift position of an electronically controlled transmission (not shown) driven by the engine 12 so that the traveling speed of the vehicle converges to the target speed value set by the driver. A speed running control device 101 is connected so as to be able to send and receive signals. This constant speed traveling control I device t101 includes a fifth
As shown in the figure, the SET switch 102 is turned on when changing the target value of the traveling speed to a higher value than the previous value, and after canceling the constant speed traveling, the light returns to the constant speed traveling state again. When the ON operation is performed, the RESU
ME switch 103 and C0A, which is turned on when setting the vehicle's target speed value lower than the previous value.
ST switch 104 is connected, and movable contacts 102a to 104a of these three switches 102 to 104 are grounded.

Furthermore, the control unit 100 has a built-in comparator 106 that amplifies the DC voltage, and the negative input terminal 106a of the comparator 106 is connected to the fixed contact 102b of the SET switch 102 so as to be able to input a signal. The positive input terminal 106b is connected via a resistor to a DC power supply 105 that applies a positive voltage and to the ground side. Furthermore, the output terminal 106C of the comparator 106 is connected to the transistor 107 via a resistor.
On the other hand, the collector 107b of the transistor 107 is connected to the DC power supply 109 which applies a positive voltage via the solenoid 108a of the relay 108, and the emitter 107C of the transistor 107 is connected to the ground. connected to each side.

Then, the electromagnetic relay 108 glue race switch 108
b is grounded via the coil of the solenoid valve S■.

As described above, when the SET switch 102 is turned on, this side signal is amplified by the comparator 106, the transistor 107 is activated, and the electromagnetic relay 108 is activated, so that the solenoid valve SV is opened. The variable capacity ω114M50 operates as described above to forcibly set the compressor 2 to the minimum capacity state. Therefore, in this embodiment, each of the devices 102 to 109 sets the solenoid valve (configuration ffi setting mechanism) so that the compressor 2 is set to the minimum capacity in response to the command signal from the constant speed running control 21I device 101.
A capacity control means 110 for controlling 211 the SV is configured.

Next, to explain the operation of this embodiment, the air conditioner 1
, the gas refrigerant discharged from the compressor 2 is condensed into liquid refrigerant by the condenser 3, and this liquid refrigerant is expanded by the expansion valve 5, then evaporated in the evaporator 6, and then sucked into the combrella shaft 2, and then The interior of the vehicle is cooled by the heat of vaporization of the refrigerant at step 6.

While the air conditioner 1 is in operation, during normal driving in which the vehicle speed controlled by the constant speed driving control 21I device 101 stably converges to the set value, the above-mentioned SE
T-switch 102 is in an off state and its contacts are open. Therefore, the relay switch 108b of the electromagnetic relay 108 is open, and no current flows to the electromagnetic valve SV side. Therefore, the electromagnetic valve S■, which is connected to the compressor 2, is kept closed, and its variable capacity mechanism 50 Due to the operation of , the combrella pump 2 is operated in a capacity controlled state. That is,
When the rotation speed of the compressor 2 is low and its capacity is low, the pressure regulator 40 is closed and the bypass passage 39 is closed due to an increase in the pressure inside the pressurizing chamber 36 of the spool valve 32, so that the compressor 2
While the capacity of the compressor 2 is maintained at its maximum capacity, when its capacity increases due to an increase in the number of rotations of the compressor 2, the pressure regulator 40 opens due to the accompanying pressure drop in the suction chamber 29, and during the valve operation, the pressure regulator 40 opens. The pressure in the pressurizing chamber 36 of the spool valve 32 decreases, the valve body 34 moves to open the bypass passage 39, and the gas refrigerant is bypassed inside the compressor 2, thereby reducing the capacity of the compressor 2. It is controlled to decrease as the rotational speed increases.

On the other hand, when the driver turns on the SET switch 102 of the constant speed cruise control device 101 for acceleration while driving, the contact 102b of the switch 102 is closed and the comparator 106 and transistor 107 are turned on.
is activated, the electromagnetic relay 108 is activated, and the electromagnetic valve S■ is opened. As a result of the opening operation of the solenoid valve S■, the suction chamber 29 enters an intermediate pressure state, and the pressure inside the suction chamber 29 and the intermediate pressure are balanced, and as a result, the valve body 34 of the spool valve 32 is In FIG. 4, the compressor 2 is positioned at the rising end position, and by keeping the bypass passage 39 fully open, the amount of refrigerant bypassed to the suction chamber 29 becomes maximum, thereby fixing the capacity of the compressor 2 to the minimum capacity.

Therefore, in this way, the SET of the constant speed cruise control device 101
When the switch 102 is turned on and it is necessary to accelerate the vehicle, the internal capacity control of the compressor 2 is forcibly prohibited from the outside, and the compressor 2 of the engine 12 is fixed in the minimum capacity state. By reducing the load for driving the vehicle, the proportion of the engine output to the drive wheels can be increased accordingly, and the acceleration performance of the vehicle can be improved to quickly converge to the target speed value.

(Second example) Next, a second embodiment will be described based on FIG. 6.

In the second embodiment, the basic MIi structure (
1 to 4) is the same as the first embodiment, the explanation of the same parts as in FIGS. 1 to 3 will be omitted, and only the different parts will be explained with respect to FIG. 4.

In this embodiment, the solenoid valve S■ shown in FIG. 4 is interposed in a communication passage 49 that communicates the first pressure chamber 42 of the pressure regulator 40 with the communication passage 37 in a normally open state (as indicated by the broken line in the figure). , the communication passage 49 and the suction chamber 29 are not in direct communication. In other words, the communication path 51 is not provided. Therefore, in this embodiment, when the solenoid valve S■ is in the open state, the variable displacement ff1ll mechanism 50 is operated to bring the compressor 2 into the internal control state, while when the solenoid valve S■ is closed, the spring chamber The valve body 34 of the spool valve 32 is adjusted so that the sum of the biasing force of the spring 38 and the pressure inside the spring cavity 35 becomes smaller than the intermediate pressure of the pressurizing chamber 36 due to the decrease in the pressure inside the spool valve 35. The capacity of the compressor 2 is set to the maximum capacity by keeping the bypass passage 39 in the full-term state and keeping the refrigerant bypass barrier to a minimum. Therefore, the solenoid valve S■ functions as a capacity setting v1 which drives the variable capacity or another 4ff50 so that the bypass passage 39 is fully opened, and sets the refrigerant discharge capacity to the maximum. .

In addition, as shown in FIG.
, ``The above c built into the constant speed control device 101 having substantially the same configuration as the above first embodiment.

The movable contact 104'a of the normally ROFF (7) COAST switch 104', which is closed when the AST button (not shown) is turned on, is grounded, and the fixed contact 1°4'b is connected via the renoid 108a of the electromagnetic relay 108. It is connected to a DC power supply 111 that applies a positive voltage. moreover,
The relay switch 108b of the electromagnetic relay 108 is grounded via the coil of the electromagnetic valve SV.

As described above, when the C0AST switch 104' is turned on in response to a command from the constant speed cruise control device [ff101], the electromagnetic relay 108 is activated, the electromagnetic valve S is closed, and the variable valve S is turned on. ff1tjl@50
is operated as described above to forcibly set the compressor 2 to the maximum capacity state. Therefore, the C0AST switch 104' and the electromagnetic relay 1
08 constitutes a capacity control means 110 that controls the solenoid valve (capacity setting mechanism) S■ so that the compressor 2 is set to the maximum capacity in response to a command signal from the constant speed running control device 101.

Next, to explain the operation of this embodiment, the air conditioner 1 operates as in the first embodiment.

Then, when the set value of the constant speed cruise control device 101 is almost converged and a stable running condition is maintained, the solenoid valve S is kept open, and the variable capacity control am mechanism 50 is operated. The compressor 2 is operated under capacity control as in the first embodiment.

In response to this, the driver presses the C0AST button of the constant speed cruise control device 101 while driving, and the C0A8
When T-switch 104' is turned on, contact 10
4'b is closed, the electromagnetic relay 108 is activated, the relay switch 108b is closed, current flows through the circuit on the electromagnetic valve SV side, and the electromagnetic valve S■ is closed. Due to the closing operation of the solenoid valve sV, the pressure inside the spring chamber 35 decreases, and the sum of the biasing force of the spring 38 and the pressure inside the spring chamber 35 becomes smaller than the intermediate pressure of the pressurizing chamber 36, and as a result, the spool By positioning the valve body 34 of the valve 32 at the lower end position in the figure and keeping the bypass passage 39 fully open, the bypass suspension of the refrigerant to the suction chamber 29 side is minimized, thereby fixing the capacity of the compressor 2 at the maximum capacity. be done.

Therefore, in this way, C0A of the constant speed cruise control device 101
When ST104' is turned on and it is necessary to decelerate the vehicle, the internal capacity control of the compressor 2 is forcibly prohibited from the outside and the compressor 2 is fixed in the maximum capacity state. By increasing the load for driving the compressor 2, so-called engine braking can be fully utilized accordingly, and the deceleration performance of the vehicle can be improved and speedy convergence to the target speed value can be achieved.

(Third example) Next, a third embodiment will be described based on FIG. 7.

Also in this embodiment, the air conditioner 1, the variable Wfa type compressor 2, the variable capacity 141150, and the capacity setting m@SV
The configuration (see FIGS. 1 to 4) is the same as that of the first embodiment, and the explanation thereof will be omitted.

FIG. 7 shows a schematic configuration of a control unit 100 as an external control device arranged in this embodiment.
Reference numeral 15 denotes a first transistor built into the constant speed running control device 101, and the base 115a side of the first transistor 115 is connected to a throttle sensor TS that detects the engine load from the intake air amount of the engine 12, and a throttle sensor TS that detects the running speed of the vehicle. It is connected to the vehicle speed sensor SS for detection. Further, the emitter 115C side is grounded, and the collector 115b side is connected to the electronically controlled transmission 12a of the engine 12 so that signals can be sent and received. Constant speed running control device 1
Change the gear ratio from 4th gear to 3rd gear from 01 to gearbox fff12a.
A control signal having a negative value that should be switched quickly is output. In addition, the control unit 10
0 has a built-in comparator 116 that amplifies the DC voltage, and the negative input terminal 116 of the comparator 116
a is connected to the collector 115b side of the first transistor 115 and the electronic iIJ type transmission t212a by a signal line, and its positive input terminal 116b is connected to the DC power supply 117 that applies a positive voltage and to the ground side through resistors, respectively. connected. The output terminal 116C of the comparator 116 is connected to the second transistor 1 through a resistor.
It is connected to the base 118a side of 18 so as to be inputtable.

The emitter 118c side of the second transistor 118 is grounded, and the collector 118b side is connected to the DC power supply 1 that applies a positive voltage via the solenoid 108a of the electromagnetic relay 108.
Connected to 09. The configuration of other parts of the electromagnetic relay 108 is the same as that of the first embodiment, and the explanation thereof will be omitted.

As described above, the throttle sensor TS or vehicle speed sensor SS
When a control signal having a negative value is output from the constant speed control device 101 via the emitter 115b of the first transistor 115 in response to a detection signal from the second transistor 11
8 is activated, and then the electromagnetic relay 108 is activated, and the electromagnetic valve SV is opened, and the variable volume 1f is activated.
The compressor 2 is configured to operate in the same manner as in the first embodiment to forcibly set the compressor 2 to the minimum capacity state. Therefore, the electromagnetic relay 108, the first . Second
Transistor 115, 118 and comparator 116
capacity control means 1 for controlling the electromagnetic valve (capacity setting mechanism) SV so that the compressor 2 is set to the minimum capacity according to the command signal of the constant speed running control I table device 01;
10 are configured.

Next, to explain the operation of this embodiment, the constant speed traveling side t
When the set value of 11B@101 is substantially converged and a stable running condition is maintained, the solenoid valve SV is kept closed, and the compressor 2 is operated according to the first embodiment by the operation of the variable capacity control AM mechanism 50. Similarly, it is operated under capacity control.

On the other hand, when the engine load increases due to curves, hill climbing, etc. while the vehicle is running, the constant speed traveling side device a 1101 sends the transmission device 12a a negative value to switch the gear ratio from 4th gear to 3rd gear. When the control signal is output, the comparator 116 amplifies the control signal, the second transistor 118 is activated, the electromagnetic relay 108 is activated, and the electromagnetic valve SV is closed. This opening operation of the solenoid valve S2 produces the same effect as in the first embodiment, and the capacity of the compressor 2 is fixed at the minimum capacity.

Therefore, the engine load increases during curves, hill climbs, etc., resulting in constant speed driving.

When a control signal to switch the gear ratio from 1 to 3 is output from 1 to the transmission 12a, the internal capacity control is forcibly prohibited from the outside of the compressor 2.
Since the compressor 2 is fixed at the minimum capacity state, the load on the engine 12 for driving the compressor 2 can be reduced, and the proportion of the engine output to the drive wheels can be increased accordingly, which improves the running performance of the vehicle. can be improved.

Therefore, the first aspect of the present invention explained above. 2nd, 3rd
In any of the embodiments, while the automatic control of the internal capacity by the variable capacity compressor 2 is utilized during normal running of the vehicle, the electromagnetic valve (capacity setting ms>sv is operated to forcibly control the capacity of the compressor 2 to the maximum capacity or minimum capacity according to the type of command signal from the constant speed running side RN device 101, thereby compensating the output required by the engine 12 at that time. The driving performance of the vehicle can be improved.

In the above embodiment, a through-vane type variable capacity compressor 2 is used as the variable capacity compressor 2, but it goes without saying that other types of variable capacity compressors such as a swash plate type may also be used.

(Effects of the Invention) As explained above, according to the present invention, in a vehicle FL device, a compressor driven by an on-vehicle engine is selected between a variable capacity operating state and a maximum capacity operating state depending on the refrigerant suction pressure. As a variable capacity compressor,
Depending on the type of command signal of the constant speed running 11ilJ immediate device,
By prohibiting the internal capacity control of the compressor mentioned above and fixing the capacity at the maximum or minimum capacity state, the automatic control of internal capacity by the variable internal capacity compressor can be utilized during normal driving of the vehicle while accelerating. ,
During deceleration, the compressor load can be reduced to i1 to compensate for the required output of the engine, and the driving performance of the vehicle can be improved.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of the present invention. 2 to 4 show common parts of the first to m3 embodiments of the present invention, FIG. 2 is an overall configuration diagram thereof, FIG. The figure is a schematic cross-sectional view. 5 to 7 are schematic circuit configuration diagrams of the first to third embodiments, respectively. 1...Air conditioner, 2...Compressor, 21...
Suction boat, 22...Discharge boat, 39...Bypass passage, 50...Variable displacement mechanism, S■...Solenoid valve (
Capacity setting compensation 1), 100...control unit,
102...Constant speed running side a device, 110...Capacity 1 t
i! J means. Patent applicant Mazda Motor Corporation - Agent 1) Hiroshi! 111 Figure 2 Figure 7 Figure 11U (Each f Hayabusa 1 Hinop means) Figure 5 1B6 Figure 11U (Photograph lP'll Doudan)

Claims (1)

[Claims] (1) A suction port that sucks refrigerant, a discharge port that discharges the refrigerant that has been sucked in from the suction port and has undergone a compression stroke, and a bypass passage that bypasses the refrigerant to the suction side during the compression stroke of the refrigerant; An external control device that externally controls a variable capacity compressor for an air conditioner driven by an engine mounted on a vehicle, the external control device having a variable capacity mechanism that controls opening and closing of a bypass passage according to the suction pressure of refrigerant, The compressor is provided with a capacity setting mechanism that sets the refrigerant discharge capacity to a maximum or minimum by driving the variable capacity mechanism so that the bypass passage is fully closed or fully opened, and the vehicle running speed is set to a set value. The variable speed control device is characterized by comprising capacity control means for operating the capacity setting mechanism so that the compressor is set to a maximum capacity or a minimum capacity depending on the type of command signal of the constant speed running control device held in the variable speed control device. External control device for capacity compressor.