JPH0321517A - Air-conditioning control device - Google Patents

Abstract

PURPOSE:To have quick temp. falling characteristic at the time of cooling and a good feeling of air-conditioning by operating a variable capacity compressor in the large capacity at the start of the cooling operation until a specified number of stops is attained, and changing over into small capacity operation when the ambient temp. of an evaporator is below a certain value. CONSTITUTION:An evaporator 4 is installed downstream a blower 3 of a duct case 1. An expansion valve 6, receiver tank 7, capacitor 8, and variable capacitor compressor 9, which constitute the cooling cycle, are sequentially connected wtih a refrigerant piping 5 connected with this evaporator 4. This compressor 9 is driven under control by a control unit 14 on the basis of signals from an intra-coupe temp. sensing means 10 and a refrigerant temp. sensing means 11. The compressor 9 is operated in a large capacity at the start of the cooling operation until a specified number of stops is attained. When after this the ambient temp. of the evaporator 4 is lower than a certain value, changing-over shall take place into a small capacity.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an air conditioning control device that can provide rapid temperature drop characteristics and a good cooling feeling during cooling.

(Prior Art) Generally, this type of control device is equipped with a variable capacity compressor, and the capacity of the compressor is variably controlled to obtain a desired air conditioning feeling. For example, in Japanese Utility Model Publication No. 61-46018, it is stated that at the beginning of cooling operation, the compressor is operated at a large capacity to rapidly cool the passenger compartment, and when the ambient temperature of the evaporator reaches a preset temperature during this cooling process, the compressor The capacity is switched from large capacity to small capacity, after which the compressor is stopped when the above ambient temperature reaches the freezing temperature, and when the above temperature rises to a preset temperature, the drive is resumed, and from then on in these temperature ranges. A vehicle air conditioning control system is shown in which the compressor is driven in cycling mode. (Problem to be Solved by the Invention) However, with this conventional control device, even when the average temperature inside the vehicle is high, when the ambient temperature of the evaporator reaches a predetermined temperature, the compressor is switched to a small capacity.
There was a problem in that the blowing temperature became high, making it impossible to obtain rapid temperature drop characteristics and a good cooling feeling.

It is an object of the present invention to solve these problems and provide an air conditioning control device that can provide rapid temperature drop characteristics and a good cooling feeling during cooling. (Means for Solving the Problems) Therefore, the air conditioning control device of the present invention includes a variable capacity compressor, and the operation of the compressor is turned on and off by temperature detection means that detects the ambient temperature of the evaporator. O. F
In an air conditioning control device that performs F control, by operating the compressor at a high capacity at the beginning of cooling operation until it is stopped a predetermined number of times, it is possible to achieve rapid temperature drop characteristics during cooling and uniform indoor temperature, and to achieve the above-mentioned predetermined level. After the number of stops, the compressor capacity can be changed to a small capacity only when the ambient temperature of the evaporator is below a predetermined temperature, so that the compressor can be operated at a small capacity under indoor conditions that allow true capacity changes. It is characterized by being able to obtain good air conditioning filling.

(Example) Hereinafter, an illustrated example in which the present invention is applied to a vehicle air conditioning control device equipped with a variable capacity compressor will be described. In FIGS. 1 to 3, reference numeral 1 denotes a duct case that houses an air conditioning unit, and an inside/outside air switching door 2 and a blower 3 are provided on the upstream side of the duct case, and an evaporator 4 that constitutes a cooling cycle is provided on the downstream side of the blower 3. is installed.

A refrigerant pipe 5 is connected to the evaporator 4, and the pipe 5
The expansion valve 6 and the receiver tank 7 that constitute the cooling cycle
．． jl5, a capacitor 8, and a variable capacity compressor 9 are inserted.

Among these, a temperature switch 1O is provided at the outlet of the evaporator 4 as a means for detecting the temperature in the vehicle compartment, and the switch 10 is configured to adjust the outlet temperature to its set temperature t z , t
ONL within the range of s ( tz < t 3 )
, and when the temperature is higher than the set temperature t3, they are turned OFF and turned ON. An OFF signal can be input to a control unit to be described later, and the ON signal prompts a change in the capacity of the compressor 9, and the OFF signal maintains the current capacity of the compressor 9. Further, the refrigerant conduit 5 connected to the refrigerant outlet side of the evaporator 4 is provided with a defrost thermoswitch 11 as refrigerant temperature detection means, and the switch l1 is set to the freezing temperature t.

(t o < t Z . t s ) O at the time of detection
The signal is input to the counter of the control unit to be described later, and the relay connected to the switch 11 is demagnetized, the electromagnetic clutch (not shown) is disconnected, and the drive of the compressor is stopped, while the set temperature tl is (t.<1.<12) When detected, ONL enables the compressor to be driven. The compressor 9 is made driveable via the electromagnetic clutch that intersects the rotational force of the engine, and is equipped with a known capacity setting means 12 and a capacity variable means 13, of which the capacity setting means 12 has 1,000 stages. control unit l
Based on the four control signals, a signal corresponding to the desired set capacity can be output to the variable stage l3, and as the capacity variable means 13, a known electromagnetic valve of this kind is employed in the embodiment. The amount of refrigerant discharged can be adjusted by opening and closing the valve. The capacity setting stage 12 and the capacity variable means 13 are described in, for example, Japanese Utility Model Publication No. 46018/1983 and Japanese Patent Application Laid-open No. 62-21.
8669 and 63-266178 can also be adopted.
Reference numeral 4 is installed at a suitable location in the vehicle, and is equipped with a microcomputer inside, and a control routine as shown in FIG. 2 is stored in the computer.

That is, the control unit l4 controls the air conditioner switch 15 [hereinafter . The control operation can be started by turning on the A/C switch (A/C switch 15), and at the start of the control, a built-in counter can be reset. The OFF signal from the defrost thermoswitch 11 is input, and after the A/C switch 15 is turned on, the number of times the switch 1l is turned off can be counted.

The computer stores a predetermined number N of counts n accumulated by the counter, a count number determination step for comparing and determining their magnitude, and each control routine after the determination, and among these, the predetermined number N is set according to the cooling temperature decreasing characteristics or cooling feeling desired by the occupant. For example, if it is desired to increase the temperature decreasing rate and obtain a strong cooling feeling, the upper limit number of times N is set to be larger.

In addition, in the count number determination step, if the count number n of the counter is smaller than the specified number of times N, the compressor 9 is driven at the current capacity, for example, 100% capacity,
While strengthening the cooling temperature decreasing characteristic, if the defrost thermo switch l1 is turned OFF during the cooling mode, the OFF
The F signal is input to the counter, the count number of the counter is set to n+1, and the compressor 9 is stopped at the same time. On the other hand, if the count number n of the counter is larger than the specified number of times N, the solenoid valve which is the capacity variable means is turned on under the condition that the temperature switch 10 is turned on, and the defrost thermoswitch l1 is turned on as a natural condition. , the capacity of the compressor 9 is switched to a small capacity, for example 30%. After changing the capacity of the compressor 9, the control routine for changing the capacity is continuously controlled from the determination step of the count number n, on the condition that the A/C switch 15 is turned on, and during that time, the blowing temperature of the evaporator 4 is equal to or higher than the set temperature t3. When the temperature rises to , the temperature switch 10 is turned off, and the capacity of the compressor 9 can be driven at the large capacity before the change, provided that the defrost thermoswitch 11 is turned on.

In addition, l6 is a power source such as a battery, l7 is an air mix door, and l8 is a heater core.

(Function) The air conditioning control device configured in this way has an A/C switch A.
The ON operation of /C 1 5 starts the control operation by the control unit 14, and at the same time as this start, the count number of the built-in counter is reset and the system waits for a signal from each switch 10.11. In addition, the control unit 14 determines the magnitude of the count number n of the counter and the initially set specified number of times N, on the condition that the A/C switch 15 is ON, and controls each capacity of the compressor 9 based on the determination result. select.

In this case, at the beginning of the cooling operation, as mentioned above, the count number of the counter is reset and the count is set to zero, so the relationship n<N is established, and the large capacity of the compressor 9 in FIG. A control routine is selected. On the other hand, when the A/C switch 15 is turned on, the compressor 9 is driven, and at the beginning of its operation, that is, at the beginning of cooling, it is driven at a preset large capacity, for example, 100% capacity, which is the maximum refrigerant discharge capacity. Rapidly cools the passenger compartment.

In this way, the temperature around the evaporator 4 decreases as shown in FIG. 3, and this temperature becomes the set temperature t. In this embodiment, when the freezing temperature is reached, this is detected by the defrost thermoswitch l1 installed in the refrigerant conduit 5 on the outlet side of the evaporator 4, and the switch 11 is turned off.

Therefore, the OFF signal of the switch 1l is input to the counter of the control unit l4, and the count number of the counter is set to n=1, while the switch 1l
The relay (not shown) connected to 1 is demagnetized, the electromagnetic clutch (not shown) is disconnected, the compressor 9 is stopped, and the cooling operation is interrupted. Therefore, when the temperature around the evaporator 4 gradually rises and reaches the set temperature 1, this is detected by the defrost thermoswitch 11.
1 is turned on, the compressor 9 is driven and the cooling operation is restarted.

When the drive of the compressor 9 is resumed, the A/C switch 15 is turned on as a natural condition, and the count number n of the counter and the initially set specified number of times 11N are judged again. In this case where the capacity control routine is selected, the count number of the counter is set to n=1 as described above, so if the specified number of times N is set to 1, the relationship n≧N=1. Therefore, in FIG. 2, if the small capacity routine of the compressor 9 is selected, and on the other hand, if N=2 is set as in the embodiment, then the relationship n<N=2 is established, and in the same figure, the compressor 9 is 9 large capacity routine is selected again. Therefore, the compressor 9 operates again at 100% capacity to rapidly cool the passenger compartment. As described above, in the present invention, since the compressor 9 is operated at a high capacity for a prescribed number of times N at the beginning of the cooling operation, the temperature decrease rate of the air conditioner is rapid and a good cooling feeling can be obtained. In this way, the temperature around the evaporator 4 reaches t again. is detected by the defrost thermo switch 1l, and when the switch 11 is turned off, the signal is input to the counter in the same manner as described above, and the count number of the counter is set to n=2, while the compressor 9 is turned off. stop and
Cooling operation is interrupted. After that, the temperature around the evaporator 4 gradually rises, and when the temperature reaches the set temperature t, this is detected by the defrost thermoswitch 11, and the switch 1
1 is turned on, the compressor 9 is driven and cooling operation is restarted.

When the drive of the compressor 9 is restarted, the A/C switch 15 is naturally turned on, and the count number n of the counter and the initially set specified number of times N are judged again. The number of counts is n
Since n≧N=2, the routine for the small capacity of the compressor 9 in FIG. 2 is selected. In the above routine, before the capacity change control, the blowing temperature of the evaporator 4 is checked, and if this is equal to or higher than the set temperature t3, the temperature switch IO is turned OFF.
If the set temperature is within the range of t2 to t3, the switch 1
0 is turned ON. When the switch 10 is turned off, the capacity change control operation is stopped and a transition is made to a large capacity operation control routine, while when the switch IO is turned on, the capacity change control is executed. Therefore, the above check confirms the current cooling state of the cabin and the uniformity of the cabin temperature, and then checks the defrost thermo switch 1.
Since it has the role of correcting the control according to 1, even when the average temperature of the passenger compartment is high as in the past, the capacity is switched to a small capacity, the blowing temperature becomes higher, and the temperature drop characteristics of the air conditioner are reduced.
That's not the case. The ON signal of the switch 1O is input to the control unit 14, and the control signal is input from the control unit 14 to the capacity setting stage 12 of the compressor 9, and from the 1,000 stages 12 to the solenoid valve which is the variable capacity 1,000 stages l3. It will be done. Therefore, when the solenoid valve is ONL, the discharge amount of the refrigerant is adjusted to be reduced to a predetermined amount.
%, and the compressor 9 is operated at a small capacity on the condition that the defrost thermo switch 11 is turned on. Since such a small capacity operation of the compressor 9 is executed only when the cabin temperature is substantially stabilized as described above, the compressor 9 is switched to a large capacity again as described later, and this is turned ON. It takes a long time to turn off,
Also, since the stable operating state of the compressor 9 is maintained for a long time even after that, the compressor 9 is not frequently turned on.
N. This eliminates the OFF operation and provides stable driving performance of the vehicle. In this way, while the compressor 9 is being operated at a small capacity, the control unit l4 executes the judgment of the count number n of the counter and the selection of the capacity change control routine based on the judgment, on the condition that the A/C switch 15 is ON. During the control process, the temperature in the passenger compartment gradually rises, and when the blowout temperature of the evaporator 4 reaches the set temperature L3 as shown in Fig. 3, the compressor 9 is switched to high capacity operation at 100% capacity, and the temperature in the passenger compartment is maintained. Rapidly restores the feeling of cooling.

(Effects of the Invention) As described above, the air conditioning control device of the present invention includes a variable capacity compressor, and controls the operation of the compressor in 4. , ON. by temperature detection means for detecting the ambient temperature of the evaporator. In an air conditioning control device that performs OFF control, since the compressor is operated at a high capacity until the compressor is stopped a predetermined number of times at the beginning of cooling operation, it is possible to achieve rapid temperature drop characteristics and uniform indoor temperature during cooling, and
After stopping for the specified number of times, the compressor capacity can be changed to a small capacity only if the ambient temperature of the evaporator is below a specified temperature. This has the effect of allowing the compressor to operate at a small capacity under true conditions in which the indoor capacity can be changed without having to change the air conditioner, thereby providing a good air conditioning feeling.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing an embodiment of the present invention, FIG. 2 is a flowchart showing a control system of the present invention, and FIG. 3 is a control characteristic diagram showing a control operation of the present invention. 4... Evaporator, 9... Compressor 1L...
・Picture detection means Fig. 2

Claims (1)

[Claims] It is equipped with a variable capacity compressor, and the operation of the compressor is turned on and off by temperature detection means that detects the ambient temperature of the evaporator. In an air conditioning control device configured to perform OFF control, the compressor is operated at high capacity at the beginning of cooling operation until it is stopped a predetermined number of times, and after the above predetermined number of stops, when the ambient temperature of the evaporator is below a predetermined temperature, the compressor capacity is reduced. An air conditioning control device characterized by being able to change the capacity.