JPS584621A - Controller for air conditioner of automobile - Google Patents

Abstract

PURPOSE:To control cooling operation to be wasteless, by connecting a means of detecting the wet-bulb temperature of intake air, to a control circuit for regulating the operation of an evaporator. CONSTITUTION:When at least one of a thermoswitch 13 for the wet-bulb temperature of intake air and a thermoswitch 18 for blowoff air is turned off, an electromagnetic clutch 24 is disengaged to stop a compressor 25. A level is set for the wet-bulb temperature on the basis of such a region of the relation between temperature and humidity that the person in the room of automobile feels comfortable. If the set level is 12 deg.C, cooling operation is stopped when the wet-bulb temperature of the intake air is not higher than 12 deg.C. A conventional region A of cooling operation stoppage is based on the dry-bulb temperature. Another region B based on the wet-bulb temperature is added to avoid unnecessary cooling operation. Besides, excessive drying is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for controlling the operation of an air conditioner for an automobile.

Generally, an air conditioner for an automobile has an evaporator and a heater core, and is configured to cool the intake air (outdoor air or indoor air) with the evaporator, heat it with the heater core depending on the mode of use, and discharge it into the room. The control device that controls the operation of the air conditioner is equipped with an intake air temperature detection means for detecting the temperature of the intake air, and controls the operation of the evaporator on and off based on the detection result of the intake air temperature detection means. It has become. However, in conventional control devices, the -F installed air temperature detection means detects only the dry bulb temperature of the intake air, and humidity is irrelevant. Cooling operation is also performed when the humidity is low and feels comfortable enough to the eye, or when the air is dry and will become too dry if cooling continues any longer. In this respect, problems of wasted energy and excessive drying occurred.

SUMMARY OF THE INVENTION Therefore, the present invention aims to provide a control device for an air conditioner for an automobile that can save energy and prevent excessive drying by preventing unnecessary cooling operations as described above.

Hereinafter, the present invention will be explained with reference to illustrated embodiments.

FIG. 1 schematically shows the configuration of an automotive air conditioner. In the figure, 1 is an intake blower, 2 is an intake air (
air intake door that switches between indoor air and outdoor air;
3 is a cooling case, 4 is an evaporator installed in this cooling case 6, 5 is a blowout adjustment section, 6 is a heater core installed in this blowout adjustment section 5, 7 is a vent outlet, 8 is a defroster outlet, 9 is a floor air outlet.

The blowout adjustment section 5 is provided with an air mix door 10, a vent door 11, and a floor door 12, and has a usage mode,
That is, each door 10.11. By opening and closing the '12, it is possible to adjust the air blowing direction, blowing temperature, etc.

1 is a thermoswitch C for detecting intake air temperature (hereinafter referred to as the first thermoswitch), which is provided on the peripheral wall of the cooling case 6 in front of the evaporator 4. This first
The thermoswitch 13 has a temperature sensing section 14 formed by filling a capillary tube with a thermal expansion gas such as Freon gas, and a diaphragm type switch operating section 15.
4 is wrapped with a water-conducting material 16 such as gauze or cloth, so that the wet bulb temperature of the intake air can be detected.

The end of the water guiding material 16 is introduced into a water reservoir chamber 17 formed below the evaporator at the bottom of the cooling case 5 and receiving condensed water generated in the evaporator 4 .

In this way, the water in the water reservoir chamber 17 is guided to the temperature sensing part 14 of the first thermoswitch 16 through the water guide material 16. According to this embodiment, in which the waste water from the evaporator 4 is used as a water supply source to the first thermoswitch 16 as a wet bulb temperature detector, a water source exclusively for the switch 13 is separately added. Since it is not necessary, the configuration is simple. Moreover, since there is no fear that the water in the water reservoir chamber 17 will run out, there is no need to take the trouble of replenishing water, and the wet bulb temperature can always be detected accurately.

In addition, a temperature sensing part 19 and a sui-nochi actuating part 2 are provided on the peripheral wall behind the evaporator 4 in the cooling case filter.
A thermoswitch for detecting outlet temperature consisting of 0 (hereinafter referred to as
A second thermoswitch (referred to as a second thermoswitch) 18 is provided. This second thermoswitch 18 serves to prevent excessive cooling by stopping the cooling operation when the dry bulb temperature of the cooling air from the evaporator 4 falls below a predetermined value (for example, 0°C). .

In addition, in Fig. 2, 1. 2nd car thermos sui nochi 13.
By placing the 18 temperature sensing parts 14 and 19 directly in the air movement path, or by providing a baffle plate in front of both temperature sensing parts 14 and 19, since the passing air tends to have relatively uneven temperature, It is desirable to measure the temperature so that it detects as uniform a temperature as possible and the ambient temperature.

Above 1. A control circuit in which the second thermos fittings 13 and 18 are incorporated is shown in FIG. In the figure, 21 is a fan switch, 22 is a blower motor whose speed is adjusted by this fan switch 21, and 26
24 is an electromagnetic clutch connecting this compressor 26 and an engine section (not shown); 2nd thermo switch 13.18 and this electromagnetic crank notch 2
4 excitation coil 24. are connected in series. Therefore, the first. When at least one of the second thermoswitches 13 and 18 is turned off, the electromagnetic clutch 24 is disconnected and the rotation of the compressor 23 is stopped, thereby stopping the cooling operation of the evaporator 4. 25
is a key switch.

The first thermoswitch 13 is turned off when the wet bulb temperature of the intake air falls below a predetermined value. It goes without saying that the off-set temperature of the first thermoswitch 16 is selected based on the range in which the occupants feel comfortable from the relationship between temperature and humidity, and in the case of this embodiment, the off-set wet bulb temperature is set at 12°C. That is, when the wet bulb temperature of the intake air falls below 12° C., the first thermoswitch 13 is turned off and the cooling operation of the evaporator 4 is stopped.

In order to make it easier to understand the on/off range of the cooling operation by the first thermoswitch 13, a psychrometric diagram is shown in FIG. In the figure, the area surrounded by the thick line is the cooling operation stop area, and the other area, that is, the area where the wet bulb temperature is 12° C. or higher, is the cooling operation area. To explain this in comparison with a conventional control device, in the conventional device, the cooling operation is stopped when the dry bulb temperature is, for example, 12°C or lower. Area A on the left side is the cooling operation stop area.

Therefore, when using the apparatus of the present invention, an area B on the right side of the dotted line A within the bold line frame is added as a cooling operation stop area to the conventional cooling operation stop area A. Area A where the wet bulb temperature is 12°C or less.

In case B, as is clear from FIG. 5, almost comfortable conditions can be maintained in terms of the relationship between temperature and humidity.

Therefore, according to the device of the present invention, unnecessary cooling operation can be cut by the amount of the area B mentioned above.

Therefore, it is possible to save energy and prevent excessive drying.

By the way, as mentioned above, if the wet bulb temperature is 12 degrees Celsius or less, comfortable atmospheric conditions can be maintained in most of the areas A and B, but in reality, comfort cannot necessarily be maintained in the high temperature areas. be.

Therefore, in the second embodiment shown in FIG. 6, a third thermoswitch 26 for detecting the dry bulb temperature of the intake air is connected in parallel with the first thermoswitch 13.

This third thermoswitch 26 is set to turn on at a high temperature, for example, at a dry bulb temperature of 25° C. or higher. In this way, even if the wet bulb temperature is below 12°C, the dry bulb temperature will be 25°C.
When it becomes difficult to maintain comfort due to the above, cooling operation is started, so that comfortable conditions common to everyone can be reliably maintained. In this example, the fifth
The region to the left of the dotted line opening within the bold line frame in the figure is the cooling operation stop region.

Note that the off-set temperature of the first thermoswitch 13 may be changed as appropriate around the above-mentioned 12° C. in consideration of various conditions. The same holds true for the on-set temperature of the sixth thermoswitch 26 in the second embodiment.

Further, the type and structure of each thermoswitch 13, 18, 26 and the water guide structure for the first thermoswitch 1 may be arbitrarily selected from various methods other than those of the above embodiments.

As described above, the present invention uses a wet bulb temperature detection means as a temperature detection element for intake air to control cooling operation, and thereby detects both temperature and humidity, compared to conventional detection using only dry bulb temperature. The intake air temperature detection function can be performed based on the following. Therefore, according to the present invention, it is possible to control the cooling operation in a practical and efficient manner, thereby realizing energy saving and prevention of excessive drying.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention. Fig. 1 is a schematic configuration diagram of an air conditioner, Fig. 2 is an enlarged view of the cooling case part of the same equipment, and Fig. 3 is a sectional view taken along Fig. 2 - L1. , 4th
The figure shows a control circuit A. FIG. 5 is a psychrometric diagram for explaining the control action, and FIG. 6 is a control circuit diagram showing another embodiment. 4... Evaporator, 6... Heater core, 13...
・Thermoswitch as means for detecting wet bulb temperature of intake air, 14... temperature sensitive part of the switch, 16... water conducting material,
17...Water pool room. Patent applicant: Toyo Kogyo Co., Ltd.

Claims (1)

[Claims] 1. In an air conditioner for an automobile that has an evaporator and a heater core and performs air conditioning by cooling and heating intake air, the intake air 7N detects the wet bulb temperature of the intake air.
A control device for an air conditioner for an automobile, characterized in that it is equipped with a detection means, and the intake air temperature detection means is connected to a control circuit that controls the operation of an evaporator. 2. The control for an air conditioner for an automobile according to claim 1, characterized in that the temperature sensing part of the intake air temperature detection means is wrapped with a water guiding material that guides water in a water pool chamber at the bottom of the evaporator. Device.