JPS6344082B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a control device for a vehicle air conditioner, particularly a vehicle air conditioner that is set to a bilevel mode or a vent mode, and air conditioned air is blown out from at least an upper outlet. The present invention relates to a control device that restricts warm air from being blown out from an upper outlet at the initial stage of operation of an air conditioner in a mode in which the air conditioner is in operation.

In general, a vehicle air conditioner mixes cold air cooled by an evaporator and warm air heated by a heater core through an air mix door, and then mixes the cool air cooled by an evaporator with warm air heated by a heater core. Air conditioning is performed by blowing air into the vehicle interior.

Conventionally, the control device for the vehicle air conditioner is configured as shown in FIG.
The output V ₀ from the arithmetic circuit 5 sends a control signal to the actuator 6 for controlling the air mix door.
_S1 is supplied to the air mix door control circuit 8, and the above output _V0 is supplied to the blower drive motor 9.
is supplied to a blower control circuit 11 which supplies a control signal _S2 to the blower control circuit 11. The signal detection circuit 4 includes a variable resistor 12 that sets a set temperature TD, a solar radiation temperature sensor 13 that detects the solar radiation temperature _ts , an inside air temperature sensor 14 that detects the vehicle interior temperature t _r , and an outside air temperature t _A. The variable resistor 12 is supplied via a resistor 16 to the inverting input side of an operational amplifier 27 constituting an operational circuit, and the solar radiation temperature sensor 13 is connected to the resistor 17. The voltage at the connection point with the resistor 17 is supplied via the resistor 18 to the inverting input side of the operational amplifier 27, and the inside temperature sensor 14 is connected to the resistor 19, and the voltage at the node with the resistor 19 is supplied via the resistor 20. Operational amplifier 27
is also supplied to the inverting input side of the outside air temperature sensor 1.
5 is connected to a resistor 21, and the voltage at the connection point with this resistor 21 is supplied via the resistor 22 to the inverting input side of the operational amplifier 27. A voltage at the connection point between the resistors 23 and 24 is supplied to the non-inverting input side of the operational amplifier 27 via a resistor 25, and a resistor 26 is connected to the negative feedback loop. The arithmetic circuit 5 consisting of the operational amplifier 27 adds and subtracts voltage signals corresponding to the set temperature T _D , inside air temperature _tr , solar radiation temperature t _s , and outside air temperature t _A , and calculates V ₀ =(K ₁ t _r +K ₂ t _s + K ₃ t _A ) − T _D The air conditioning function signal for the set temperature T _D
Output V ₀ . Note that the above K ₁ , K ₂ , and K ₃ are constants set by various resistors connected to the operational amplifier 27. _{As shown in characteristic} This output signal is shown as
V ₀ is supplied to the air mix door control circuit 8,
The air mix door control circuit 8 outputs the above output signal V ₀
Based on this, the signal _S1 shown in FIG. 2c is sent to the air mix door control actuator 6. This signal S ₁
For example, when the inside air temperature t _r becomes higher than the set temperature T _D and the output signal V ₀ becomes larger,
The maximum value is reached, and as a result, the air mix door is opened to the maximum extent to the full cooler side, and the vehicle air conditioner is set to the full cooler mode, and this signal _S1 indicates that the internal air temperature t _r decreases from the high temperature side to the low temperature side. As the internal air temperature becomes lower and the output signal V ₀ becomes smaller, the control signal S ₁ is set so that the opening degree of the air mix door becomes smaller. As a result, the air mix door is set to the full heater side, and the vehicle air conditioner is set to the full heater mode. The blower control circuit 11 also controls the second blower control circuit 11 based on the output signal V ₀ .
The signal _S2 shown in Figure b is supplied to the blower 9 side. The above control signal _S2 has its maximum value in the full cooler and full heater modes when the internal air temperature _tr is in the high temperature range or low temperature range, and this causes the blower to rotate at high speed. , when the inside air temperature t _r changes in the direction of the set temperature _TD , this signal S ₂ gradually becomes smaller, and as a result, the rotation speed of the fan gradually decreases, and is further saturated at the minimum value, causing the fan to rotate at a low speed. . Therefore, if the difference between the set temperature T _D and the inside air temperature _tr is large, the output V ₀ becomes small, so the full heater mode is set, and the amount of warm air blown increases.

However, according to conventional air conditioners for vehicles, when the outside temperature falls into the intermediate temperature range of, for example, 15°C < t _A < 25°C, such as during the middle seasons such as spring and autumn, the occupants The mode of the outlet is set to bilevel mode or vent mode, and conditioned air is blown out from both the upper outlet and the lower outlet or only from the upper outlet. On the other hand, if the inside air temperature T _r is lower than the set temperature T _D at this time, the air conditioner is set to the heater mode as described above, and the amount of warm air blown increases. This has the disadvantage that a large amount of warm air is blown out from the air outlet, and this warm air is supplied to the face of the occupant, significantly reducing the feeling of the occupant.

Furthermore, according to the conventional vehicle air conditioner, as shown in Fig. 3a, the temperature _T1 of the air blown out from the lower outlet and the temperature _T2 of the air blown out from the upper outlet Immediately after turning on the switch, the temperature suddenly drops from the high temperature side and exceeds the set temperature T _D , then rises further in the direction of the set temperature T _D , and repeats such fluctuations until it approaches the set temperature T _D. and the temperature of the air blown out from the above outlet.
This has the disadvantage that in the process of changing T ₁ and T ₂ , the inside air temperature _tr also changes, causing discomfort to the occupants.

An object of the present invention is to provide an air conditioner for a vehicle that automatically controls the mixing ratio of warm air and cold air blown out from an air outlet based on the results of arithmetic processing of various input factors for air conditioning. The gain of at least one input factor is controlled to reduce the amount of warm air blown out from the air outlet when the outlet of a vehicle air conditioner is set to bilevel mode or vent mode. This method is intended to eliminate the above-mentioned drawbacks, and will be explained in detail below using examples.

FIG. 4 is a circuit diagram showing an embodiment of a control device for a vehicle air conditioner according to the present invention, and the same parts as in FIG. 1 are denoted by the same reference numerals. In the present invention, in the control device for a vehicle air conditioner shown in FIG. 1, the resistor 26 connected to the negative feedback loop circuit of the operational amplifier 27 is constructed from a variable resistor as shown in FIG. The gain of the operational amplifier 27 is adjusted by controlling the resistance value of the operational amplifier 27. In FIG. 4, reference numeral 40 denotes an outside air temperature detection circuit whose output is at the L level when the outside air temperature is in the middle temperature range of, for example, 15°C to 25°C, such as in the middle of the season, and the temperature sensor 15 in FIG. It consists of _a window comparator that detects a signal with a magnitude within a predetermined range among the output signals of is supplied with the signal N ₂ from the mode position detection circuit 42 . The mode position detection circuit 42 detects whether the mode of the air outlet is set to a bilevel mode in which air is blown out from both the upper and lower outlets or a vent mode in which air is blown out only from the upper outlet. It consists of a switch that is turned on when the air outlet is in bilevel mode or vent mode, and at this time, the output signal _N2 becomes L level. The output of the NOR circuit 41 is supplied to one input terminal of NOR circuits 44, 45, 46, and 47 via an inversion circuit 43. The above NOR circuits 44 to 4
The output of 7 is supplied to each switch 48a, 48b, 48c, 48d constituting the analog switch circuit 48, and the output of the NOR circuit 44 to 47 becomes H.
When it comes to the level, each of the above switches 48a to 4
8d is turned on, and the resistors 26a and 26 are turned on, respectively.
b, 26c, and 26d are shorted. In this case, the variable resistor 26 is composed of the above-mentioned resistors 26a to 26d connected in series to the resistor ₂₆₀ , and immediately after the cooler switch 3 is turned on, the switches 48a to 48d are turned on. Therefore, the resistance is 26 ₀ ,
The resistance value is the minimum value, but as the switches 48a to 48d are gradually turned off as time passes, the resistance value increases. Reference numeral 49 denotes a clock pulse generating circuit that generates clock pulses of a predetermined period, the output of which is supplied to one input terminal of a NAND circuit 50, and the output of the NAND circuit 50 is supplied to the clock input terminal of a binary counter 51. Also, the clear input terminal of this binary counter 51 is connected to the cooler switch 3.
A resistor 52 and a capacitor 53 with one end connected to the side
The input signal from the connection point is supplied. The output signals from each output terminal Q _A to Q _D of the binary counter 51 are supplied to the other input terminals of the NOR circuits 44 to 47 and also to the input terminal of the NAND circuit 54, and the output signal of the NAND circuit 54 is as described above. It is supplied to the other input terminal of the NAND circuit 50. The binary counter 51 is cleared immediately after the cooler switch 3 is turned on and a pulse input is supplied to the clear input terminal, all outputs from the output terminals Q _A to Q _D are reset to L level, and then the clock pulse generation circuit Count up the clock pulses from 49. When the outputs of the output terminals Q _A to Q _D of the counter 51 all go to H level, the output of the NAND circuit 54 goes to L level, and the gate of the NAND circuit 50 is closed. In order to prevent this, all outputs from the output terminals Q _A to Q _D of the counter 51 are held at H level.

Note that the resistor 26 and the analog switch circuit 4
8 constitutes the gain adjustment means of the present application, the mode position detection circuit 42 constitutes the mode detection means, the clock pulse generation circuit 49, the NAND circuits 50, 54, the binary counter 51, etc. constitute the timekeeping means, the NOR circuits 41, 44 to 47, and the inverting circuit. 43 respectively constitute gain control means.

The operation of the control device for a vehicle air conditioner according to the present invention having the above configuration will be described below. First, when the outside air temperature is in the middle temperature range of 15°C to 25°C in the middle of the season, the output signal of the outside air temperature detection circuit 40 is
_N1 becomes L level, at this time the mode of the air outlet is set to bilevel mode or vent mode, and the output signal from the mode position detection circuit 42
When _N2 becomes L level as above, NOR circuit 41
The output of the inverting circuit 4 becomes H level.
The output from 3 becomes L level, and the NOR circuit 44
An L level signal is supplied to one of the input terminals of 47 to 47. On the other hand, at this time, the cooler switch 3
When turned on, a clear input is supplied to the clear input terminal of the binary counter 51 by the pulse obtained from the connection point between the resistor 52 and the capacitor 53, so the counter 51 is cleared and its output terminals Q _A to Q _D All the outputs of the NOR circuits 44 to 47 are at the L level, and therefore the output signals of the NOR circuits 44 to 47 are all at the H level, and the switches 48a to 48d making up the analog switch circuit 48 are all turned _on . The resistance value is set to the minimum value. In the control circuit of FIG. 1, when the resistance value of the resistor 26 connected to the feedback circuit of the operational amplifier 27 becomes the minimum value, the output characteristic of the operational amplifier 27 changes as shown in FIG. 2a.
The gain of the operational amplifier 27 becomes minimum as shown by _P1 .

Next, when the binary counter 51 counts up the clock pulses from the clock pulse generation circuit 49, the output from the output terminals Q _A to Q _D becomes the output terminal.
The level increases sequentially from Q _A to Q _D (for example, 1, 0, 0, 0, 0, 1, 0, 0,
0, 0, 1, 0, 0, 0, 0, 1, 1, 1,
1, 1), so that the outputs of the NOR circuits 44 to 47 sequentially go to the L level from the NOR circuit 44, so the switches 48a to 48d are sequentially set to OFF, and the resistors 26a to 26d are sequentially turned off. Since the resistors 26a to 26d are connected in series to ₂₆₀ , the resistance value of the resistors 26a to 26d is 26d.
If the resistance value of the variable resistor 26 is set to increase in the direction shown in _FIG.
The gain changes in the _P3 direction and becomes the normal gain X, which substantially increases the gain.

That is, according to this embodiment, when the outside air temperature is in the middle temperature range of 15°C to 25°C, such as in the middle of the season, if the air outlet mode is set to bilevel mode or vent mode, the cooler switch 3 Immediately after turning on the operational amplifier 27, the gain of the operational amplifier 27 is small, so even if the difference between the set temperature T _D and the inside air temperature T _r is large, the output V ₀ cannot become small, so the air mix door is turned to the full heater side. It becomes difficult to control the air blower, and it becomes difficult to control the blower to a high speed rotation level. That is, for example, unless the inside air temperature _tr falls by a considerable amount with respect to the set temperature _TD , the air mix door will not be set to the full heater mode and the blower will not rotate at high speed. In this way, in the bi-level mode or the vent mode, the amount of warm air blown out is suppressed, so it is possible to solve the problem of warm air being blown out from the upper air outlet and reducing the feeling of the occupants. . In addition, as shown in Figure 3b, the temperature _T1 of the air blown out from the lower outlet and the temperature _T2 of the air blown out from the upper outlet slowly approach the set temperature _TD immediately after the cooler switch is turned on. As a result, the temperature overshoots the set temperature T _D as in the conventional case.
There is no risk that the temperature will fluctuate around this set temperature T _D , and therefore the temperature _tr in the vehicle interior gradually approaches the set temperature T _D , making it possible to further improve the feeling of the occupants. Next, when the binary counter 51 counts up and all outputs from its output terminals Q _A to Q _D become H level, the output of the NAND circuit 54 becomes L level, so the gate of the NAND circuit 50 is closed, and the binary counter 51 The pulse from the clock pulse generation circuit 49 is no longer supplied to the variable resistor 26.
The resistance value of is held at the maximum value. That is, after a predetermined period of time has elapsed, the gain of the operational amplifier 27 is restored to its normal high level. Note that even if the gain becomes large in this way, there is no risk that a large amount of warm air will be blown out from the air outlet because the temperature inside the vehicle has risen to near the set temperature T _D at this point.

In the present invention, the difference between the set temperature T _D and the inside air temperature _tr is detected, and when this detection result reaches a predetermined value, the outside air temperature detection circuit 40 is activated to perform calculation. The gain of the amplifier may also be adjusted.

Further, although the present invention has been described as adjusting the gain of the operational amplifier 27, the present invention is not limited to this.
Alternatively, the gain of the signal sent from the controller may be adjusted independently. Further, the control circuit for the vehicle air conditioner according to the present invention can be easily realized by using, for example, a microcomputer.

As explained above, according to the control device for a vehicle air conditioner according to the present invention, the mixing ratio of warm air and cold air in the air blown out from the air outlet is adjusted based on the air conditioning control input factor. In the air conditioner for a vehicle, a gain adjustment means for adjusting the gain of the input factor for air conditioning control, and a mode detection for detecting that the mode of the air outlet is set to a mode in which air is blown out from at least the upper outlet. means, a timer for timing a predetermined time immediately after the start of the air conditioner, and a gain adjustment means based on the outputs of the mode detection means and the timer, and is set to a mode in which air is blown out from the upper outlet. The upper air outlet When set to the mode that blows air from the air, the blowing rate of warm air immediately after the air conditioner starts can be suppressed, so warm air is not supplied toward the occupant's face, and this prevents the occupant's face from being supplied. The feeling can be improved, and since the blowout temperature gradually approaches the set temperature, the inside air temperature also gradually approaches the set temperature, which prevents the inside air temperature from becoming abnormally high immediately after the air conditioner starts. It is possible to solve the problem of causing discomfort to the occupants.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing an example of a conventional control device for a vehicle air conditioner, and FIGS. 2 and 3 a and b show a conventional control device for a vehicle air conditioner and a vehicle air conditioner according to the present invention. FIG. 4 is a characteristic diagram showing the operation of the control device of the device. FIG. 4 is a circuit diagram showing an embodiment of the control device of the vehicle air conditioner according to the present invention. 1...Power supply, 2...Ignition switch,
3... Cooler switch, 4... Detection circuit, 5...
Arithmetic circuit, 8...Air mix door control circuit, 1
1... Blower control circuit, 26... Resistor, 40...
Outside air temperature detection circuit, 48... Analog switch circuit, 49... Clock pulse generation circuit, 51...
binary counter.

Claims (1)

[Scope of Claims] 1. In a vehicle air conditioner that adjusts the mixing ratio of warm air and cold air in air blown out from an air outlet based on an input factor for air conditioning control, the input factor for air conditioning control is gain adjustment means for adjusting the gain; mode detection means for detecting that the mode of the air outlet is set to a mode in which air is blown out from at least the upper outlet; and a gain adjustment means based on the outputs of the mode detection means and the timekeeping means to adjust the gain of the input factor for air conditioning control when the mode is set to blow out air from the upper outlet. 1. A control device for a vehicle air conditioner, comprising: gain control means that sets the gain to a small value immediately after starting the air conditioner, and gradually increases the gain to a predetermined level during a predetermined period of time. 2. The control device for a vehicle air conditioner according to claim 1, wherein the gain of the input factor for air conditioning control is set small immediately after the air conditioner is started when the outside air temperature is within a predetermined range. 3. The vehicle according to claim 1, wherein the gain of the air conditioning control input factor is set to be small immediately after starting the air conditioner when the difference between the set temperature in the vehicle interior and the inside air temperature is a predetermined value. Control device for air conditioning equipment.