JPS5822712A - Controller of air conditioner for vehicle - Google Patents

Abstract

PURPOSE:To improve the comfort of passagers given by the air conditioner of the type in which warm air and cool air are sent mixedly at an adjusted ratio by a method wherein a gain of an air conditioning input factor immediate after the atsrting of the air conditioner is set at a relatively small value. CONSTITUTION:When an outdoor temperature is within a range from 15-25 deg.C and an operation mode is HIGH or VENT, the output N1 of an outdoor temperature detecting circuit 40 and the output N2 of a mode position detecting circuit 42 are both LOW level. At this time, if a cooler switch 3 is turned ON, a binary counter 51 is cleared by a pulse signal obtained from a connection point of a resistor 52 and a condensor 53, and therefore, the outputs from terminals QA-QD become LOW level and NOR circuits 44-47 becomes HIGH level. Thus, all the switches 48a-48d are turned ON, and therefore, the resistance is set at a value of a resistor 26 only. This value is the minimum value of resistance, and the gain of the control circuit become minimum. Accordingly, the warmed air is not applied to the faces of the passangers, resulting in an improvement of comfort in the passanger room.

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 pie level mode or 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.

Generally, an air conditioner for a vehicle mixes cold air cooled by an evaporator and warm air heated by a heater core using an air mix door, and then mixes the air into the vehicle interior through an upper outlet, a lower outlet, or both of these outlets. Air conditioning is performed by blowing air out.

Conventionally, the control device for the vehicle air conditioner is configured as shown in FIG. The output vO from the arithmetic circuit 5 is supplied to the air mix door control circuit 8 which supplies the control signal Sl to the actuator 6 for controlling the air mix door, and the upper supply voltage Vo is supplied to the blower drive motor 9. Blower control circuit 11 that supplies control signal 82k
supplied to The signal detection circuit 4 includes a variable resistor 12 that sets the set temperature TD, a solar radiation temperature sensor 13 that detects the solar heat temperature ts, an inside air temperature sensor 14 that detects the vehicle interior temperature tr, and an outside air temperature tA. 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 a resistor 17. The connection point voltage with this resistor 19 is supplied to the inverting input side of the operational amplifier 2T via a resistor 18, and the inside air temperature sensor 14 is connected to a resistor 19, and the connection point voltage with this resistor 19 is supplied to the operational amplifier 2T via a resistor 20. The outside temperature sensor 15 is also connected to a resistor 21 , and the voltage at the connection point with this resistor 21 is supplied to the inverting input side of the operational amplifier 27 via a resistor 22 . 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 comprising the operational amplifier 27 operates at the set temperature TD.

Add/subtract the voltage signal corresponding to the inside air temperature 'r + solar radiation temperature LS + outside air temperature tA, and calculate VO = (K1tr+ to 2to, +KBtA) - 'r[)
The air conditioning function signal Vo for the set temperature TD shown by
Output k. In addition, in the above Kl, 2. 3 is a constant set by various resistors connected to the operational amplifier 27. As shown in the characteristic X of FIG. 2(a), the output signal Vo is equal to the internal air temperature tr'+M air temperature tA.

As the solar radiation temperature t8 increases, its magnitude increases linearly.This output signal Vo is supplied to the air mix door control circuit 8, which outputs the above-mentioned output signal Vo. Figure 2 (
The signal S11 of C) is sent to Unitaro for near mix door use. This signal S1 is, for example, the set temperature T[)
On the other hand, when the internal air temperature 1r becomes high and the output signal VO fluctuates greatly, the maximum value is reached, and this causes the air mix door to be opened to the maximum extent toward the full cooler side, and the municipal air conditioner is switched to the full cooler side. mode, and this signal S1 is set so that the magnitude thereof gradually decreases as the internal air temperature tr decreases from the high humidity side to the low temperature side, thereby decreasing the opening degree of the air duck store,
Furthermore, when the internal air temperature becomes low and the output signal VO becomes small, the control signal Sl becomes the minimum value, the air mix door is set to the full heater side, and the vehicle air conditioner is set to the full heater mode. Become. Further, the blower control circuit 11 supplies a signal 82k to the blower 9 side in FIG. 2(b) based on the output signal Vo. The 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. , the inside air temperature tr is the set temperature T[
) direction, this signal S2 gradually becomes smaller,
As a result, the rotational speed of the blower gradually decreases, and is further saturated at the minimum value, so that the blower enters a low-speed rotation state. Therefore, when the difference between the set temperature TD and the inside air temperature tr is large, the output Vo becomes small, so the full heater mode is set, and the amount of warm air blown increases.

However, according to the conventional vehicle air conditioner, when the outside air temperature is, for example, 15°C <tA during the middle seasons such as spring and autumn,
<If the temperature reaches the mid-range of about 25℃, the normal air outlet mode is set to pie level mode or vent mode by the occupant, and conditioned air is supplied from both the upper and lower outlets or only from the upper outlet. It's blown out. - At this time, if the internal air temperature t is lower than the set temperature T[), the air conditioner will be set to the heater mode as described above, and the amount of warm air blown will increase. However, a large amount of warm air is blown out from the upper air outlet, and this warm air is supplied to the face of the occupant, resulting in a disadvantage in that the comfort of the occupant is significantly reduced.

According to the conventional air conditioner for vehicles, as shown in Fig. 3(a),
), the temperature T of the air blown out from the lower outlet
Immediately after turning on the cooler switch, the temperature T2 of the air blown out from the upper outlet suddenly decreases from the high side and exceeds the set temperature TD, and then the set temperature T[]
By repeating these fluctuations, the set temperature T
'D, and in the process in which the temperatures Tl and T2 of the air blown out from the air outlet fluctuate, the inside air temperature tr also fluctuates, 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. Controlling the gain of at least one input factor to reduce the volume of warm air blown from an air outlet when the outlet of a vehicle air conditioner is set to pie level mode, vent mode, etc. This method eliminates the above-mentioned drawbacks, and will be explained in detail below using actual winding 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 components as in FIG. 1 are designated by the same reference numerals. In the present invention, in the control device for a vehicle air conditioner shown in FIG.
The resistor 26 connected to the negative feedback circuit is constructed from a variable resistor as shown in FIG. 4, and the gain of the operational amplifier 27 is adjusted by controlling the resistance value of the resistor 26. In Figure 4, 40 is the middle season when the outside temperature is
For example, this is an outside air temperature detection circuit whose output is at the L level when the temperature is in the medium temperature range of 15°C to 25°C. The output N1 is supplied to one input terminal of a NOR circuit 41, and the signal N2 from the mode position detection circuit 42 is supplied to the other input terminal of the NOR circuit 41. The mode position detection circuit 42 is configured to set the mode of the air outlet to a pie level 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 outlet is in pie level mode or vent mode, and at this time the output signal N2 becomes L level. The output of the NOR circuit 41 is passed through an inversion number 43 to a NOR circuit 44,
45°46.47 is supplied to one input terminal. The outputs of the NOR circuits 44 to 47 are the respective switches 48a and 48b constituting the analog switch circuit 48.

48e and 48d, and is supplied to the NOR circuits 44 to 4.
When the output of T becomes H level, each of the switches 48a to 48d is turned on, and the respective resistors 26a and 26b are turned on.
, 26c, and 26d are shorted.

In this case, the variable resistor 26 is composed of the resistors 26a to 26d connected in series to the variable resistor 26Fi and the resistor 26o. Immediately after the cooler switch 3 is turned on, the switches 48a to 48d are turned on. Because of this, the resistance becomes the resistance of the resistor 26o, and its resistance value becomes the minimum value, but as time passes, the resistance of the switch 48a increases.
48d gradually turns off, so its resistance value increases. Reference numeral 49 denotes a clock pulse generation circuit that generates clock pulses of a predetermined period.The output of this circuit is supplied to one input terminal of a NAND circuit 50, and the output of the NAND circuit 50 is supplied to a clock input terminal of a binary counter 51. Further, the clear input terminal of the binary counter 51 is supplied with an input signal from a connection point between a resistor 52 and a capacitor 53, one end of which is connected to the Coolus 1 terminal 3 side.

The output signals from the respective output terminals QA to QD of the binary counter 51 are supplied to the input terminals of the other outputs of the NOR circuits 44 to 47, and are also supplied to the input terminal of the NAND circuit 54, and the output signal of the NAND circuit 54 is circuit 50
is supplied to the input terminal of external force. 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, and all outputs from the output terminals QA to QD are reset to L level, and then the clock pulse generation circuit 49 Count up clock pulses from . When the outputs of the output terminals QA to Q[) of the counter 51 all go to H level, the output of the NAND circuit 54 goes to L level, closing the gate of the NAND circuit 5o.
Since the counter 51 blocks the pulses from the clock pulse generating circuit 49, all outputs from the output terminals QA to QD of the counter 51 are held at H level.

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 mid-season temperature range of 15°C to 25°C, for example, the output signal Nl of the outside air temperature detection circuit 4o becomes L level.
At this time, when the mode of the air outlet is set to pie level mode or vent mode and the output signal N2 from the mode position detection circuit 42 becomes L level as above, the NOR circuit 4
1 becomes H level, and as a result, the output from the inverting circuit 43 becomes L level, and the NOR circuits 44 to 47
An L level signal is supplied to one input terminal of. At this time, when the cooler switch 3 is 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 It is cleared, and the outputs of its output terminals QA to QD all go to L level, and therefore the output signals of NOR circuits 44 to 47 all go to H level.
level, and all the switches 48a to 48d constituting the analog switch circuit 48 are turned on, so the variable resistor 26 is set to the resistance value of only the resistor 26o, and that resistance value becomes the minimum value. In the control circuit shown in 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 becomes as shown by Pl in FIG. 2(a). Therefore, the gain of this operational amplifier 27 becomes minimum.

Next, when the binary counter 51 counts up the clock pulses from the clock pulse generation circuit 49, the outputs from the output terminals QA to Q[) change from the output terminals QA to QD.
The direction becomes H level sequentially (for example, 1.0...
0.0, o, 1. o, 0.0. ．． 0. l.

o, o, o, 6. x, changes like 1, 1, 1.1)
, Therefore, the outputs of the NOR circuits 44 to 47 are also the same as the NOR circuit 4.
switch 48a in order to sequentially go to L level from 4.
The switches 48d and 48d are sequentially turned off, and the resistor 26
Since resistors a to 26d are sequentially connected in series to resistor 26°, if the resistance values of resistors 26a to 26d are set to increase in the direction of force 26d, the resistance value of variable resistor 26 will increase. Therefore, the output characteristic of the operational amplifier 2T changes from P in FIG. 2(a) to P3 power direction, becoming the normal gain 1X, and the gain becomes substantially larger.

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 mode of the air outlet is set to pie level mode or vent mode, the cooler switch 3 Immediately after turning on, the gain of the operational amplifier 27 is small, so even if the difference between the set temperature TD and the inside air temperature tr is large, the output Vo
cannot be made small, so it becomes difficult to control the air mix door to the full heater side, and it becomes difficult to control the blower to a high-speed rotation level. That is, for example, the inside air temperature t
If r does not decrease by a considerable amount with respect to the set temperature T[), the air mix door will not be set to full heater mode and the blower will not rotate at high speed. In this way, in the pie 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 deteriorating the passenger's feeling. I can guess it. In addition, as shown in Fig. 3(b), 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 gradually change to the set flow rate T' immediately after the cooler switch is turned on. As the temperature approaches D, there is no risk of overshooting from the set temperature T[) as in the conventional case, and the temperature will fluctuate around this set temperature TD. Since the vehicle approaches the vehicle gradually, the passenger's feeling can be further enhanced. Next, when the binary counter 51 counts up and all outputs from its output terminals QA to Q[) become H level, the output of the NAND circuit 54 becomes L level, so the gate of the NAND circuit 50 is closed. Then, the pulse from the clock pulse generation circuit 49 is no longer supplied to the binary counter 51, and therefore the resistance value of the variable resistor 26 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 TD at this point.

In addition, in the present invention, the set temperature TD and the inside air temperature tr
The gain of the operational amplifier may be adjusted by detecting the difference between the two, and when the detection result reaches a predetermined value, the outside air temperature detection circuit 41 is activated.

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.
The gains of the signals sent from the temperature setting device 122, the solar radiation level sensor 13, the indoor air temperature sensor 14, and the ffi air temperature sensor 15 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 macro computer.

As explained above, according to the control device for a vehicle air conditioner according to the present invention, in a vehicle air conditioner that controls the vehicle interior temperature by adjusting the mixing ratio of cold air and warm air,
When the air outlet mode of the vehicle air conditioner is set to blow air from the upper outlet, the gains of various input factors for air conditioning control are set small immediately after the air conditioner starts, so warm air is Since the blowout rate can be suppressed, warm air is not supplied toward the occupant's face, which improves the occupant's feeling.Furthermore, the blowout temperature gradually approaches the set temperature, reducing the internal air temperature. Similarly, the temperature gradually approaches the set temperature, which solves the problem of the inside air temperature becoming abnormally high immediately after the air conditioner is started, causing discomfort to the occupants.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an example of a conventional control device for a vehicle air conditioner, and FIGS. FIG. 4 is a characteristic diagram showing the operation of the control device for a vehicle air conditioner. FIG. 4 is a circuit diagram showing an example of the control device for a vehicle air conditioner according to the present invention. 1... Electric L 2... Ignition switch, 3
...Cooler switch, 4...Detection circuit, 5...Arithmetic circuit, 8...Air mix door control circuit, 11...
・Blower control circuit, 26... Resistor, 40... Outside temperature detection circuit, 4B... Analog switch circuit, 49.
... Clockz (Russ generation circuit, 51...Banary counter. Patent applicant: Diesel Kiki Co., Ltd. Agent Patent attorney: Jun Miyazono - ('1') - '3 Rent Harukayujo

Claims (4)

[Claims] (1) In a vehicle air conditioner that adjusts the mixing ratio of warm air and cold air of air blown out from an air outlet to 1 based on an input factor for air conditioning control, the gain of the input factor for air conditioning control is adjusted to at least A control device for a vehicle air conditioner, characterized in that the air conditioner is set to a small value immediately after the air conditioner is started. (2) The input factor for air conditioning control is set to a small value immediately after starting the air conditioner, and then the gain is gradually increased to a predetermined level.
A control device for a vehicle air conditioner according to paragraph 1. (3) 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 starting the air conditioner when the outside temperature is within a predetermined range. (4) Claim 1, in which 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 vehicle air conditioners.