JPH04183627A - Automotive air conditioner - Google Patents

Abstract

PURPOSE:To enable the control of optimum cooling output which corresponds to changes, even if external environment changes or heat capacity in a car changes due to increase or decrease of the number of passengers and baggages, by making on/off threshold of a compressor rise and fall by taking into considerations the conditions outside and inside car room. CONSTITUTION:An air conditioner is controlled by a controller 1. Consequently, various sensors which detect outside and inside conditions to set cooling amount, for example, a solar radiation sensor 2, an outside air sensor 3, a cooling temperature sensor 4, and an inside air sensor 5, are connected to the controller 1. Also, a temperature set device 6 which is set by user (driver) is connected to it. Further, a fuzzy computing element 13 is connected to it to assume and output on/off set point (threshold) of a compressor and input it in a comparator 14. The result which is compared in the comparator 14 is input in a compressor 11 as on/off instruction output of the compressor 11. On the other hand, an air mix damper 10, the compressor 11, and a blower 12 are connected to tire controller 1 as control object.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention relates to an automobile air conditioner, and particularly relates to improving the cooling efficiency of an automobile air conditioner.

(b) Conventional technology In automotive air conditioners, a threshold value regarding outside air temperature is set, and when the outside air temperature exceeds this threshold value, the compressor is turned on, and when the outside air temperature falls below the threshold value, the compressor is turned off.

(C) Problems to be Solved by the Invention However, since the interior of an automobile is extremely narrow compared to the interior of a house, conditions such as heat capacity fluctuate greatly depending on the increase or decrease in the number of passengers, the amount of luggage, etc. Furthermore, changes in the environment outside the vehicle due to the driving of the vehicle are extremely rapid and complex compared to changes in conditions in a general house. For these reasons, it has been difficult to maintain an appropriate temperature in the vehicle interior by fixing the on/off threshold of the compressor as in the past. In addition, because the state changes are complex and rapid,
It is difficult to maintain accuracy with conventional determination methods, and there are also problems with calculation speed.

This invention was made by focusing on these conventional problems, and it is possible to maintain an appropriate temperature inside the vehicle by changing the on/off threshold of the kelp flusher according to the environment. Its purpose is to provide automotive air conditioners.

(d) Means for Solving the Problem The invention of claim (1) of this application includes a state detecting means for detecting the external state and internal state of the vehicle compartment, and a compressor control unit based on the detected contents of the state detecting means. The present invention is characterized in that it is provided with a threshold value adjusting means for raising and lowering the on/off threshold value.

The invention according to claim (2) of this application is characterized in that, in the invention according to claim (1), the threshold value adjusting means is constituted by fuzzy inference means for inferring the threshold value based on the external state and the internal state. shall be.

(e) Function In the automotive air conditioner of the present invention, the condition detecting means detects the external condition and internal condition of the vehicle interior, and the threshold adjusting means adjusts the on/off threshold of the compressor based on the detected contents. The state detection means includes, for example, the air temperature and solar radiation outside the vehicle, the air temperature inside the vehicle, and the air temperature of the cooler (evaporator). This allows the temperature inside the vehicle to be maintained at an appropriate level even if the environment and conditions inside the vehicle change in a complex manner. Furthermore, by using fuzzy inference in the threshold value adjustment means, it becomes possible to quickly determine an appropriate threshold value even when there is a sudden and complex environmental change.

(f) Embodiment FIG. 1 is a block diagram of a control section of an automobile air conditioner which is an embodiment of the present invention. An automobile air conditioner is a device that uses engine power to drive a compressor to maintain an appropriate temperature inside the vehicle by blowing out cooled and dehumidified air mixed with interior air and outside air.

This air conditioner is controlled by a controller 1. The controller 1 is composed of a one-chip microcomputer. Sensors are connected to this controller 1 to detect external and internal conditions in order to set the amount of cooling. This sensor is solar radiation sensor 2. Outside air sensor 3. They are a cooler sensor 4 and an inside air sensor 5. The solar radiation sensor 2 is a sensor that detects the intensity of sunlight. The outside air sensor 3 is a sensor that detects the temperature outside the vehicle. The cooler sensor 4 is a sensor that detects the temperature of air cooled by a cooler (evaporator). The inside air sensor 5 is a sensor that detects the temperature inside the vehicle interior.

Furthermore, a temperature setting device 6 set by the user (driver) is connected. The detection amount SS of the solar radiation sensor 2, the detection amount TO of the outside air sensor 3, the detection amount TE of the cooling sensor 4, the detection amount TI of the inside air sensor 5, and the set amount TS of the temperature setting device 6 are input to the controller 1 as they are. Controller 1
has a built-in A/D conversion circuit, and the above detection amount is based on the A/D conversion circuit.
A fuzzy arithmetic unit 3 is connected to the controller 1, which is converted into a digital value and inputted by a D conversion circuit. The fuzzy computing device 3 receives information from the controller 1 that calculates the outside temperature To(XI)l, the rate of increase in the inside temperature TI ΔT I (xt) + the outlet temperature (temperature of cold air blown out of the outlet) TAO, and the outside temperature TO. Difference T A OT O (
x :+), air mix damper opening SW (x
s) is input. The fuzzy reasoner 13 infers and outputs the on/off set point (threshold value) of the compressor and inputs it to the comparator 14 . The detected value TE of the cooler sensor 4 is input to the comparator 14 as a compared input. The comparison result of the comparator 14 is input to the compressor 11 as an on/off instruction output for the compressor 11.

Furthermore, the controller 1 includes an air mix damper 10. Compressor II and blower 12
is connected. The air mix damper 10 is an adjustment layer that mixes the air cooled by the cooler with the air inside the vehicle or the air outside the vehicle and sets the temperature to an appropriate temperature.

In other words, the pipe that connects the cooler and the blower outlet (blower 12) is provided with an intake port that takes in outside air (air outside the vehicle or inside the vehicle), and the air mix damper adjusts the degree of opening of this intake port. It is 10. Compressor 11
is driven by the engine as described above, but the on/off of the drive is controlled by a transmission clutch. The controller 1 operates this transmission clutch. Blower]
2 is a fan provided at the air outlet. By adjusting the amount of air, it is possible to increase or decrease the amount of cold air taken into the vehicle interior, and it is also possible to adjust the coolness felt by the occupants due to the wind.

With the above configuration, the controller 1 executes the following calculations based on inputs from each sensor.

The blowout temperature TAO is set to TAO = 1, TS- to 2, TI- to 3, To- to 4,
Calculate using the formula SS+C1, and based on this value, set the opening SW of the air mix damper 12 as follows: SW=j (TAO-TE)/(6・V- for TH+)
TE) Calculated using the 1$100 formula. Here, TH is the air pressure at the outside air intake, and ■ is the vehicle speed.

Further, the air volume of the blower 12, etc. are calculated using the same type of calculation formula and determination formula. These parameters are output directly to the controlled object and also to the fuzzy calculator 13.

FIGS. 2 and 3 are diagrams showing fuzzy rules and member simplification functions set in the fuzzy arithmetic unit 13. The fuzzy calculator 13 calculates the outside temperature To(x,) input from the controller 1 and the rate of increase ΔT I of the inside temperature TI.
(X 2) l The difference between outlet temperature (temperature of cold air blown out from the outlet) TAO and outside temperature TO (Xi),
Based on the data of the air mix damper opening SW (χ,), an inference as shown in FIG. 2 is made to determine the compressor on/off set point (yl).

The fuzzy calculator 13 outputs the inference result yl to the comparator 14 as a voltage value. The comparator 14 is composed of a comparator, and compares this voltage yI with TE, which is also input as a voltage value.

If yl is large, the compressor 11 is turned off, and if TE is large, the compressor 11 is turned on. Note that this on/off set point may be provided with hysteresis.

Note that in this embodiment, fuzzy inference is performed based on the outside temperature.

This was done based on data on the rate of increase in internal temperature, the difference between outlet temperature and outside temperature, and air mix damper opening, but it is also possible to perform fuzzy inference based on other inputs to determine on/off set points. It is possible.

(□□□Effects of the Invention As described above, according to the automobile air conditioner of the present invention, the on/off threshold of the compressor is raised or lowered in consideration of the conditions inside and outside the vehicle, so that even if the outside environment changes, Furthermore, even if the heat capacity inside the vehicle changes due to an increase or decrease in the number of passengers or luggage, the cooling output can be controlled accordingly.

Furthermore, by using fuzzy reasoning to determine the upper and lower on/off thresholds, it is possible to accurately judge the changing environment of a car due to the complex relationship between multiple conditions, and to provide appropriate and efficient cooling. It becomes possible.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a control section and membership numerical aperture of an automobile air conditioner according to the present invention. 13-Fuzzy operator.

Claims (2)

[Claims] (1) A state detecting means for detecting the external state and internal state of the vehicle interior; and a threshold adjusting means for raising or lowering the on/off threshold of the compressor based on the detected contents of the state detecting means. Automotive air conditioner. (2) The automotive air conditioner according to claim 1, wherein the threshold value adjusting means is a fuzzy inference means for inferring the threshold value based on the external state and the internal state.