JPH0131523Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention is equipped with a blower, a refrigerant evaporator for cooling, and a heater core. The present invention relates to a vehicle air conditioning control device that controls the opening degree of the vehicle to provide comfortable temperature control.

[Conventional technology]

An example of this type of vehicle air conditioning control device will be described with reference to FIG.

Referring to FIG. 2, a blower 6, a cooling refrigerant evaporator 2, and a heater core 7 are arranged in the ventilation duct 1 in this order from the windward side. In the refrigerant evaporator 2,
Refrigerant is supplied from a refrigerant compressor (not shown) driven by part of the engine's power. A portion of cooling water (hot water) is supplied to the heater core 7 from a radiator (not shown) of the engine. The blower 6 takes in air from the outside air inlet 4 or the inside air inlet 5 and supplies it to the refrigerant evaporator 2. Switching between intake of inside air and outside air is performed by a switching damper 3. Air mix dampers 8a and 8b respectively interlock with the air inlet and air outlet of the heater core 7.
is provided. This air mix damper 8
a and 8b adjust the air temperature by mixing the air that passes through the heater core 7 with the air that does not pass through it. The air that has passed through or bypassed the heater core 7 is blown out into the vehicle from central and side outlets 10 or warm air outlets 11 inside the vehicle. 9 is a defrosting outlet.

The control system is divided into a refrigerant compressor control system and an automatic temperature control system. The refrigerant compressor control system includes a temperature sensing element 12 provided on or near the outlet side surface of the refrigerant evaporator 2 and a control device 30, and is activated when the start switch 16 is turned on. In other words, the refrigerant compressor control system is a frost prevention control system. That is, when the start switch 16 is turned on and the cooling operation is performed, if the refrigerant evaporator 2 becomes excessively frosted, the signal of the temperature sensing element 12 changes. The control device 30 detects this change and activates the excitation coil 26 of the electromagnetic clutch for relaying the driving force to the refrigerant compressor.
By turning off the power to the refrigerant compressor, the refrigerant compressor is stopped. Of course, once the frost has disappeared, the refrigerant compressor is driven again.

The automatic temperature control system uses air mix dampers 8a and 8.
A room temperature sensor 18 for detecting the temperature inside the vehicle, an outside temperature sensor 19, and an automatic control device 31 using a microcomputer.
Water temperature sensor 2 that detects water temperature to heater core 7
0. The temperature of the air blown into the vehicle is controlled by controlling the motor actuator 23 based on the signals from the solar radiation sensor 21 and the temperature setting device 22.
Automatic control device 31 includes a microcomputer 24 and an A/D converter 25. The automatic control device 31 also controls the vehicle interior temperature by controlling the rotation speed switching control section 13 to adjust the rotation speed of the blower 6.

[Problem that the invention attempts to solve]

This vehicle air conditioning control device turns on the start switch 16 during cooling operation, and supplies hot water to the heater core 7 as needed. The temperature inside the vehicle is controlled by controlling the opening degrees of the air mix dampers 8a and 8b by the automatic control device 31 to mix cold air cooled to a predetermined temperature by the refrigerant evaporator 2 with warm air heated by the heater core 7. This is done by controlling the rotation speed of the blower 6.

On the other hand, during heating operation, the refrigerant compressor is not necessarily operated, and the start switch 16 may be off and the refrigerant compressor control system is stopped, and the automatic control device 31 controls the rotation speed of the blower 6. Temperature control is performed by controlling the opening degrees of air mix dampers 8a and 8b. However, in this heating operation, the temperature of the air introduced through the outside air inlet 4 fluctuates depending on external conditions, so there is a drawback that temperature control tends to become unstable.

Therefore, an object of the present invention is to provide a vehicle air conditioning control device that can realize stable vehicle interior temperature control.

[Means for solving problems]

According to the present invention, a signal from a temperature sensing element that detects the temperature on or near the outlet side of the refrigerant evaporator is used to turn on the start switch of the refrigerant compressor control system.
A switching section is provided for switching the output to either a first control device that controls the refrigerant compressor or a second control device that automatically controls the temperature inside the vehicle, when the start switch is turned off. The present invention is characterized in that the signal from the temperature sensing element can be used as control information for the control device.

[Effect]

That is, in the present invention, when the start switch is turned on, refrigerant is supplied to the refrigerant evaporator, so the first
The second control device outputs the signal from the temperature sensing element to the second control device to perform frost prevention control, and the second control device uses a predetermined constant signal as a substitute for the signal from the temperature sensing device to control the temperature inside the vehicle. On the other hand, when the startup switch is turned off, the signal from the temperature sensing element is supplied to the second control device. Stable control can be achieved by automatically controlling the temperature using signals from the elements as control information.

〔Example〕

An embodiment of the present invention will be described with reference to FIG. Components that are the same as those in FIG. 2 are given the same numbers, and their explanation will be omitted. In this embodiment, the signal from the temperature sensing element 12 can be selectively supplied to the refrigerant compressor control device 15 and automatic control device 14 via the contacts of the relay 17. That is, the normally closed contact b of the relay 17 is connected to the microcomputer 24, and the normally open contact c is connected to the control device 15. relay 1
The excitation coil 7 is connected to a power source via a start switch 16.

Due to this, when the start switch 16 is turned on,
In other words, during cooling operation, common terminal a and normally open contact c
are connected. During this time, the control device 15 turns on and off the energization of the excitation coil of the electromagnetic clutch according to the signal from the temperature sensing element 12, and controls the on and off of the refrigerant compressor to prevent frost formation on the refrigerant evaporator 2. To prevent. On the other hand, in the automatic control device 14, the temperature sensing element 1
Room temperature sensor 1 while the signal from 2 is cut off.
8. The signals from the outside temperature sensor 19, water temperature sensor 20, solar radiation sensor 21 and temperature setting device 22 are converted to A/D.
In addition to receiving the digital signal converted by the converter 25, a signal with a predetermined constant value is generated, and this is regarded as temperature information at the outlet of the refrigerant evaporator 2 to control the opening of the air mix dampers 8a and 8b. The rotation speed of the blower 6 is controlled. That is, while the refrigerant compressor control system is operating, the outlet side temperature of the refrigerant evaporator 2 is controlled to repeatedly rise and fall within a certain narrow range, so it is sufficient to set the intermediate value as a constant value. .

Next, when the start switch 16 is turned off, that is, during heating operation, the common terminal a and the normally closed contact b are connected. Therefore, the automatic control device 14 receives various digital signals from the A/D converter 25 as well as actual temperature information from the temperature sensing element 12 to perform temperature control. Specifically, the microcomputer 24 presets the outlet side temperature of the refrigerant evaporator 2, that is, the ventilation air temperature, the room temperature, the outside temperature, the temperature of the radiator water supplied to the heater core 7, the presence or absence of solar radiation, and the set temperature as control information. Perform prescribed calculations. The motor actuator 23 is controlled according to the result of this calculation process, and the air mix dampers 8a, 8
Control the opening degree of b to maintain the set room temperature. The automatic control device 14 also outputs a blower rotation speed control signal to the rotation speed switching control section 13 in accordance with the above calculation processing result. Rotation speed switching control section 1
3 controls the blower rotation speed according to the blower rotation speed control signal, that is, the rotation speed such that the set room temperature is achieved. In this way, the automatic control device 14 can also use the ventilation temperature detected upstream of the heater core 7 as control information, so even when outside air, which is susceptible to external factors, is introduced as ventilation air, temperature changes can be prevented. It is possible to perform stable control regardless of the influence.

[Effect of idea]

As explained above, the present invention is equipped with a switching unit that supplies a signal from the temperature sensing element to the refrigerant compressor control system or automatic temperature control system in conjunction with the on/off of the start switch of the refrigerant compressor control system. As a result, it is possible to increase the control information in the automatic temperature control system and perform stable temperature control. Even if there are differences in the relationship between temperature and signals due to different types of refrigerant compressor control systems (differences in set values, etc.), the temperature detection signal is mechanically switched using a relay, so temperature detection appropriate for both control systems can be achieved. signals can be sent and automatic control devices can be applied universally.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a block diagram of a conventional example. In the figure, 2 is a refrigerant evaporator, 7 is a heater core, and 8 is a refrigerant evaporator.
a and 8b are air mix dampers, and 12 is a temperature sensing element.

Claims (1)

[Claims for Utility Model Registration] 1. Based on the input signal from the temperature sensing element that detects the temperature on or near the outlet side of the refrigerant evaporator,
A first control device that performs frost formation prevention control on the refrigerant evaporator by intermittent operation of the refrigerant compressor, and arithmetic processing of signals from the temperature sensing element, room temperature sensor, outside temperature sensor, temperature setting device, etc. and a second control device that controls the opening degree of the air mix damper and the number of rotations of the blower, and outputs the signal from the temperature sensing element to the first control device, or 1. An air conditioning control device for a vehicle, comprising a switching unit for switching output to a control device. 2. The vehicle air conditioning control device according to claim 1, characterized in that a relay is used as the switching section. 3. The air conditioning control device for a vehicle according to claim 1, wherein the switching unit is activated in conjunction with opening and closing of a starting switch for the refrigerant compressor. 4 When the signal from the temperature sensing element is output to the first control device by activation of the switching unit, the second control device outputs a signal of a predetermined constant value from the temperature sensing element. The air conditioning control device for a vehicle according to claim 1, characterized in that the air conditioning control device performs arithmetic processing as a substitute for the signal.