JPH0224219A - Solenoid clutch control device for variable capacity type compressor - Google Patents

Abstract

PURPOSE:To preferably perform the capacity return of the title compressor or the like by decreasing the capacity of the compressor driven by an engine through a clutch while maintaining a power supplied to the clutch at the value directly before acceleration, in detecting the acceleration of a vehicle. CONSTITUTION:A vehicle is provided with a solenoid clutch 1 operated according to a supplied power and a variable capacity type compressor 2 driven by the engine through the solenoid clutch 1. In this case, the acceleration of the vehicle is detected by a means 3. After the detection, during a specific short time, the capacity of the compressor 2 is controlled to be decreased by a means 4. Further, after the detection by the means 3, during the specific short time, the supplied power to the solenoid clutch 1 is controlled to be maintained by a means 5 at the value directly before detection by the means 3. With this arrangement, it is possible to preferably maintain the acceleration property in acceleration of the vehicle while preferably perform the capacity return of the compressor 2 after the acceleration, without the slippage of the solenoid clutch 1.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an electromagnetic clutch control device for a variable capacity compressor for a vehicle.

(Prior Art) Conventionally, in an electromagnetic clutch control device for a variable displacement compressor for a vehicle of this type, for example,
As shown in Publication No. 3931, the minimum current to be applied to the electromagnetic clutch is determined in accordance with the discharge pressure, rotation speed, etc. of the compressor so that the electromagnetic clutch generates the torque necessary to drive the compressor. There is something like this.

(Problems to be Solved by the Invention) However, in such a configuration, the torque of the electromagnetic clutch has poor ability to follow load fluctuations caused by changes in the capacity of the compressor. For example, when the capacity of the compressor is reduced when the vehicle accelerates, and when the capacity of the compressor is suddenly increased and restored at the end of acceleration, there is a problem in that the electromagnetic clutch is likely to slip due to insufficient torque.

Therefore, in order to cope with such a problem, the present invention provides an electromagnetic clutch control device for a variable capacity compressor for a vehicle, while maintaining good acceleration performance when accelerating the vehicle.
The aim is to restore the capacity of the compressor at the end of the acceleration without causing the electromagnetic clutch to slip.

(Means for solving the problem) In solving the problem, the structural features of the present invention are as follows:
As illustrated in FIG. 1, in a vehicle equipped with an electromagnetic clutch 1 that is engaged depending on the supplied power, and a variable capacity compressor 2 that is operated by power transmitted from the engine by the engagement of the electromagnetic clutch 1, a detection means 3 for detecting acceleration of the vehicle; a capacity control means 4 for controlling the capacity of the compressor 2 to decrease for a short time after detection by the detection means 3; A power control means 5 is provided for controlling the supplied power so as to maintain it at the value immediately before detection by the detection means 3 for a short period of time.

(Operation and Effect) By configuring the present invention in this way, when the vehicle is accelerating, the capacity control means 4 controls the capacity of the compressor 2 to decrease for a short time after the detection by the detection means 3. The power control means 5 controls the power supplied to the electromagnetic clutch 1 so that it does not substantially change before and after detection by the detection means 3. Therefore, the acceleration performance of the vehicle can be ensured satisfactorily in accordance with the torque reduction due to the reduction in the capacity of the compressor 2, and even when the capacity of the compressor 2 is increased and returned to normal at the end of acceleration, the torque of the electromagnetic clutch 1 is increased to the compressor 2. The torque is always maintained greater than the torque of the As a result, without causing the electromagnetic clutch 1 to slip,
The capacity of the compressor 2 can be restored.

(Example) Hereinafter, one example of the present invention will be described with reference to the drawings.
The figure shows an example in which the present invention is applied to a vehicle near conditioner. Near conditioner is air duct 1
0, and inside this air duct 10 is a blower 1.
1. An evaporator 20 of a refrigeration cycle RC, an air mix damper (not shown), etc. are arranged in this order. The refrigeration cycle Rc has a variable capacity compressor 30, and this compressor 30 compresses the refrigerant from the evaporator 20 through the pipe Pl according to its capacity, and discharges the compressed refrigerant into the pipe P2. In this case, the capacity of the compressor 30 changes in proportion to the opening degree of the solenoid valve 31 attached to the compressor 30. Moreover, the operation of the compressor 30 is
This is caused by torque transmission from the engine of the vehicle to the compressor 30 upon selective engagement of the electromagnetic clutch 32 attached to the vehicle. However, in this embodiment, a dry single-plate electromagnetic clutch is used as the electromagnetic clutch 32.

Moreover, the refrigeration cycle Rc has a condenser 40, and this condenser 40 condenses the compressed refrigerant from the pipe P2 and supplies it as a condensed refrigerant into the gas-liquid separator 50 through the pipe P3. The gas-liquid separator 50 supplies the liquid phase component in the refrigerant from the pipe P3 as a refrigerant to the evaporator 20 through the pipe P4, the expansion valve 60, and the pipe P5. The evaporator 20 cools the airflow from the blower 11 that is to be blown into the cabin of the vehicle through the air mix damper or the like.

Next, an electric control circuit for the solenoid valve 31 and electromagnetic clutch 32 of the compressor 30 will be explained. The operation switch SW is operated to generate an operation signal when operating the near conditioner. Temperature setting device 7
0a is generated as a set temperature signal by setting a desired temperature in the vehicle interior.

The inside temperature sensor 70b detects the actual temperature inside the vehicle and generates an inside temperature detection signal. The blowout temperature sensor 70c detects the actual temperature of the air flow blown out from the evaporator 20 and generates a blowout temperature detection signal. The throttle switch 80 detects a rapid change in the opening degree of the throttle valve of the engine of the vehicle and generates an acceleration detection signal.

The A-D converter 90 converts the set temperature signal from the temperature setting device 70a, the inside temperature detection signal from the inside temperature sensor 70b, and the blowing air vortex detection signal from the outlet temperature sensor 70c into a set temperature digital signal and an inside temperature digital signal. and digitally convert the output temperature into digital signals. The microcomputer 100 executes the computer program in cooperation with the accelerator switch 80 and the A-D converter 90 according to the flowchart shown in FIG. Arithmetic processing for controlling each of the drive circuits 110 and 120 is performed. However, the above-mentioned computer program is stored in the ROM of the microcomputer 100 in advance. Note that the microcomputer 100 is connected to the battery B via the ignition switch IG of the vehicle.
It is put into the operating state by power supply from the operation switch SW.
Starts execution of the computer program in response to an operation signal from the computer.

In this embodiment configured as described above, when the ignition switch IG is closed, the vehicle is started with the engine started, and the microcomputer 100 is put into operation.

Next, when an operation signal is generated from the operation switch SW, the microcomputer 100 starts executing a computer program at step 200 according to the flowchart in FIG. The values of the set temperature digital signal, inside temperature digital signal, and blowout temperature digital signal from the -D converter 90 are input as the set temperature Tset, the inside temperature Tin, and the blowout temperature Te. If the acceleration detection signal is not generated from the throttle switch 80 at this stage, the microcomputer 100 selects rNo.
, and in step 231, the necessary blowout temperature Tea of the air flow into the vehicle speed chamber is determined based on the set temperature Tset, the inside temperature Tin, and the blowout temperature Te, and in step 232, the blowout temperature Te, etc. is determined. Target capacity C of the base compressor 30
vo is determined, and in step 233, the duty ratio DT representing the target opening degree of the solenoid valve 31 and the target applied voltage Vczo to the electromagnetic clutch 32 are set as the target capacity Cv.
Determine based on o.

After that, the microcomputer 100 performs step 24.
0, the method of changing the voltage applied to the electromagnetic clutch 32 is determined according to the state of change from the actual capacity of the compressor 30 (namely, the preceding target capacity) to the current target capacity Cvo. In such a case, the clutch torque Tcz due to the engagement of the electromagnetic clutch 32 is always higher than the change in the compressor torque Tcom due to the change in the capacity of the compressor 30, so that the target applied voltage Vczo is adjusted so that the electromagnetic clutch 32 does not always slip. The phase is made to be different from that of the duty ratio DT.

At this stage, if the electromagnetic clutch 32 is in a disengaged state (assuming that it has been initialized to Vczo.0 in step 210), the microcomputer 100 executes the computer program from step 240 to step 24.
Proceed to 1. That is, in step 241, Vcz
Considering that both the capacity of the compressor 30 and the operation of the electromagnetic clutch 32 become unstable when starting the electromagnetic clutch 32 from o.0, the target applied voltage VcJo is set according to the curve Laa as shown in FIG. First set it to 100 (%) so that it can be specified, and then set the duty ratio DT.
is increased linearly as specified by the curve Naa, and after reaching the desired value of DT, it is opened for a certain time and Vcj is increased.

Arithmetic processing is performed to reduce the value to a desired value.

Therefore, each step 220-240, 241 and 25
During the repeated process of execution of the computer program passing through 0, the target capacity Cvo is calculated according to the above-described calculation process in step 241.

The duty ratio DT and the target applied voltage VcJo are repeatedly determined, and in step 250, the duty ratio D
T and target applied voltage VCJ! 0 are repeatedly generated as the duty output signal and the voltage output signal, respectively. Therefore, the microcomputer 100 .
On the other hand, the drive circuit 110 is controlled based on the duty output signal from the microcomputer 100 so that the opening degree of the solenoid valve 31, that is, the duty ratio DT follows the curve Naa. The drive is controlled by

Therefore, the clutch torque Tcz of the electromagnetic clutch 32 is
When the electromagnetic clutch 32 is activated, the curve La shown in FIG.
On the other hand, the compressor torque Tcom of the compressor 30 is controlled so as to be specified by the curve Nab shown in FIG. Therefore, even if the operation of the electromagnetic clutch 32 and the capacity of the compressor 30 are unstable at the time of starting the electromagnetic clutch 32, the clutch torque Tα of the electromagnetic clutch 32 without slipping and the compressor torque Tco of the compressor 30 are maintained.
m can be realized accurately and smoothly with a phase difference as shown in FIG. 4, and as a result, the cooling capacity of the refrigeration cycle Rc when the electromagnetic clutch 32 is activated can be smoothly ensured.

When the computer program proceeds to step 240 in this state, the microcomputer 100
If the computer program proceeds to step 242 based on the judgment that the electromagnetic clutch 32 and the compressor 30 are in a steady state, the compressor torque Tcom and the clutch torque Tc4 are set to each curve Nbb as shown in FIG. and Lbb, the duty ratio DT is set to the target applied voltage VCJ! Decrease linearly while leading by a predetermined phase with respect to 0, while
Compressor torque Teom and clutch torque Tcz
When increasing along the curves Nbb and Nba, calculation processing is performed such that the duty ratio DT is linearly increased while being delayed by a predetermined phase with respect to the target applied voltage Vcio. Therefore, the clutch torque Tc4
is controlled so that it always exceeds the compressor torque Tcom, and as a result, the capacity control of the compressor 30, that is, the cooling capacity control in the steady state of the refrigeration cycle Rc, can be accurately controlled without slipping of the electromagnetic clutch 32. can be realized.

After that, when an acceleration detection signal is generated from the throttle switch 80, the microcomputer 100 performs step 230.
At step 260, it is determined that the vehicle is rYESJ, and at step 260, processing is performed when the vehicle is accelerated. Therefore, in this acceleration process, in response to the determination of rYESJ in step 230, the duty ratio is set to DT·0 (see curve Nca) as shown in FIG. 6, while the target applied voltage VcJ ! o
Processing is performed such that the steady state value immediately before the determination of rYEsj in step 230 is maintained as it is. In such a case, the processing is performed for the following reasons. That is, the time during which the capacity of the compressor 30 is reduced so as not to deteriorate the acceleration performance of the vehicle during acceleration is usually extremely short, and during this time,
The rotational fluctuations of the compressor 30 due to engine rotational fluctuations are severe, and the discharge pressure and torque fluctuations of the compressor 30 are also significant.

In addition, when the compressor torque is restored immediately before acceleration when the acceleration of the vehicle ends, if the voltage applied to the electromagnetic clutch 32 is decreased at the same time as acceleration and is restored immediately before acceleration upon completion of acceleration, the clutch torque TCi becomes the compressor torque Tcom. In order to prevent the occurrence of slippage in the electromagnetic clutch 32 at the end of acceleration due to failure to follow the acceleration, the above-mentioned processing during acceleration is performed.

Therefore, in the process of repeating the operations through each step 230, 260 and 250, the compressor 3 by DT.
Target applied voltage V to the electromagnetic clutch 32 under the minimum capacity of 0
cio is maintained thereafter as the value immediately before the acceleration of the vehicle started. Therefore, even if the compressor torque Tcom decreases along the curve Ncb in FIG. 6, the clutch torque Tcf is maintained at the value just before acceleration along the curve Lcb in FIG.
Even if om increases along the curve Ncb, the clutch torque T
+4 always exceeds the compressor torque Tcom, and as a result, the electromagnetic clutch 32 does not slip, and the vehicle has good acceleration performance and the compressor torque Tcom returns accurately at the end of acceleration with good followability. It can be done.

At the end of such acceleration, if the determination in step 230 is rNOJ again, the computer program proceeds to step 240. If it is determined in step 232 that the capacity of the compressor 30 is to be rapidly changed from a small capacity to a large capacity based on the target capacity tCvo, the microcomputer 100 advances the computer program to step 243 to increase the capacity. Perform processing.

In this capacity increase process, as shown in FIG. 7, arithmetic processing is performed so that the target applied voltage vczo (see curve Lda) increases step by step with a predetermined phase advance relative to the duty ratio DT (see curve Nda). It will be done. Therefore, in the process of repeating calculations passing through each step 230.240.243.250, based on the phase difference between VcJo and DT as described above, clutch torque Tα (see curve Ldb) is changed to compressor torque Tcom (curve Ndb). controlled so that it always exceeds.

Therefore, the capacity of the compressor 30 can be increased to a desired large capacity without causing the electromagnetic clutch 32 to slip.

Further, when the computer program proceeds to step 240 as described above, if it is determined that the capacity of the compressor 30 is to be changed from a large capacity to a small capacity based on the target capacity Cvo in step 232, the microcomputer 100 computer program step 2
44, where a capacitance reduction process is performed. In this capacitance reduction process, as shown in FIG.
(see curve Lca) is duty ratio DT (curve Nea
(see) with a delay of a predetermined phase, and
Arithmetic processing is performed so that the target applied voltage Vcio is decreased linearly and the duty ratio DT is decreased stepwise. Therefore, each step 230.240.244.
250, the clutch torque T is calculated based on the phase difference between VcJo and DT as described above.
CJ (see curve Lcb) is compressor torque Teo
It is controlled to decrease so that it always exceeds m (see curve Neb). Therefore, the capacity of the compressor 30 can be reduced to a desired small capacity without causing the electromagnetic clutch 32 to slip.

Note that in implementing the present invention, the control of the electromagnetic clutch 32 is not limited to the applied voltage, but may be performed using the applied current.

Further, in implementing the present invention, the present invention is not limited to near conditioners, and may be applied to various types of refrigeration cycles such as vehicular refrigeration systems. Furthermore, the electromagnetic clutch 32 is not limited to a dry single-plate electromagnetic clutch, but may also be implemented using a dry multi-disc electromagnetic clutch, a wet multi-disc electromagnetic clutch, an electromagnetic particle electromagnetic clutch, or the like.

[Brief explanation of the drawing]

FIG. 1 is a diagram corresponding to the claims, FIG. 2 is a block diagram showing an embodiment of the present invention, and FIG. 3 is a flow chart showing the operation of the microcomputer shown in FIG.
8 are graphs showing temporal changes in duty ratio DT, target applied voltage Vcto, compressor torque ↑cow, and clutch torque TcJ-. Explanation of symbols 30... Compressor, 31... Solenoid valve, 32... Electromagnetic clutch, 80... Throttle switch, 100... Microcomputer.

Claims (1)

[Claims] In a vehicle equipped with an electromagnetic clutch that engages in accordance with supplied power, and a variable capacity compressor that operates by transmitting power from the engine through engagement of the electromagnetic clutch,
detection means for detecting acceleration of the vehicle; capacity control means for controlling the capacity of the compressor to decrease for a short period of time after detection by the detection means; 1. An electromagnetic clutch control device for a variable capacity compressor, comprising: power control means for controlling the supplied power so as to maintain the supplied power substantially at the value immediately before detection by the detection means.