JPS6233969B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an air conditioner for an automobile that performs novel operation control.

BACKGROUND ART Conventionally, as one type of automobile air conditioner, one in which an electric blower and cooling and heating heat exchangers are disposed in a ventilation duct is known. This device uses a switch to selectively command operation and stop, and when in operation, power is supplied to the electric blower to create forced air in the ventilation duct, and also to provide cooling if necessary. , operates the heating heat exchanger to adjust the temperature of the air discharged from the ventilation duct into the passenger compartment. In addition, in the stopped state, the electric blower is stopped, the heat exchange action of the heat exchanger is also stopped, and the air conditioning function of the device is completely stopped.

Therefore, in the conventional device, the temperature cannot be adjusted at all while the electric blower is stopped. Therefore, in order to obtain a comfortable air-conditioned state, the air conditioner must be kept running at all times, which reduces the power consumption of the electric blower and the load on the automobile's prime mover to drive the cooler. It's a big loss.

In view of the above problems, the present invention, in addition to air conditioning control that includes the operation of an electric blower and at least a cooler driven by an automobile prime mover, uses less power even when the electric blower and cooler are stopped. Therefore, it is an object of the present invention to provide an air conditioner for an automobile that can perform air conditioning control to the maximum extent possible.

In order to achieve this objective, the present invention operates the heater even when the electric blower and cooler are stopped, so that outside air is introduced into the ventilation duct from the inlet and discharged into the vehicle interior without using the electric blower. The heater is characterized by providing means for adjusting the amount of heat of the air. Here, the heater can utilize the heat radiated by the automobile prime mover,
Furthermore, the ventilation generated in the ventilation duct due to the running pressure while the vehicle is running can be utilized, and the power consumption is extremely small.

In addition, in a preferred embodiment, in order to maintain the temperature in the vehicle interior more stably, it is desirable to provide an electric control circuit that detects the temperature in the vehicle interior and automatically adjusts the heat exchange amount of the heater according to the detected temperature. . It is also desirable to adjust the amount of ventilation generated in the ventilation duct by the running pressure.

Further, it is preferable to use one or more sets of switches to distinguish between a normal air conditioning state and a completely stopped state of the device. For example, when the ignition switch of a motor vehicle is opened, the device is completely stopped, when the air conditioning start switch (blower motor operation command switch) is turned on, the device is operated normally, and when this switch is not turned on, only the heater is operated. It may be configured as follows.

The present invention will be described below with reference to embodiments shown in the accompanying drawings. In this embodiment, the present invention is applied to a generally known automobile air conditioner using a cold air/warm air mixing method. An outside air intake port 1a for internal air circulation and an inside air intake port 1 for internal air circulation.
b is formed, and both suction ports are used as internal and external air dampers 2.
It is opened and closed by. In the ventilation duct 1, toward the downstream side, there are an electric blower (blower motor) 3, a cooler (evaporator) 4 that forms part of the cooling cycle CC, and a heater (heater core) that forms part of the cooling water cycle HC of the engine EG. ) 5, and a temperature adjustment damper (A/M damper) 7 that adjusts the ratio of air passing through the heater core 5 and air passing through its bypass passage 6. At the most downstream part of the ventilation duct 1, there are formed upper and lower air outlets Ic and 1d for blowing out the temperature-controlled air in the duct to the upper and lower parts of the vehicle interior. It is opened and closed by the outlet damper 8.

Relatively large-diameter ventilation port 4 installed at the rear of the vehicle compartment
An opening adjustment damper 41 is arranged at 0 to adjust the amount of air discharged from the inside of the vehicle to the outside of the vehicle.

In order to perform temperature control and various operation mode controls, the control device 10 receives various information signals and executes processing based on a preset control program. It electrically commands the operation of the

As a means for inputting various information signals to the control device 10, an inside temperature sensor 21 including a heat-sensitive resistor that generates an analog voltage signal Tr' corresponding to the temperature inside the vehicle interior, and an analog voltage signal corresponding to the temperature outside the vehicle interior.
an outside temperature sensor 22 including a heat-sensitive resistor that produces Ta';
Analog voltage signal according to set temperature (set position)
A temperature setting device 23 including a potentiometer that generates Ts′, an opening sensor 24 including a potentiometer that generates an analog voltage signal Ar′ corresponding to the opening degree of the temperature adjustment damper 7, It flows into the opening sensor 25 including a potentiometer that produces an analog voltage signal Aw' corresponding to the pointer angle of the vehicle speedometer, the vehicle speed sensor 26 including a potentiometer producing an analog voltage signal Vs' corresponding to the pointer angle of the vehicle speedometer, and the heater core 5. Water temperature sensor 2 including a heat-sensitive resistor that generates an analog voltage signal Tw′ according to the temperature of the cooling water
7 is provided. Further, a switch panel 11 is provided which has command switches for operation, stop, switching of the inside/outside air damper 2, switching of the outlet damper 8, etc., and generates on/off signals for each switch.

In addition, the engine EG is used as a means for operating functional elements according to electrical commands from the control device 10.
an electromagnetic clutch 31 for intermittent driving force from to the cooling cycle CC; an electromagnetic valve 32 for opening and closing the cooling water circulation path to the heater core 5 in the heating cycle HC;
Also provided are electromagnetic valve-controlled negative pressure actuators 33, 34, 35, and 36 that use engine negative pressure to open and close the internal and external air damper 2, temperature adjustment damper 7, outlet damper 8, and opening adjustment damper 41. There is. The display panel 12 displays the operating status of the air conditioner and the control device based on the output signal of the control device 10.

Note that the control device 10 is a key switch 1 of an automobile.
When the ignition position 3 is turned on, power is supplied from the on-vehicle battery 14 to enable operation.

As shown in FIG. 2, a control device 10a selectively converts analog voltage signals from a digital computer (microcomputer) 10a, which performs digital information processing based on a preset control program, from signal input means 21 to 27 into analog signals. - An analog input interface 10b that converts the signal into digital and inputs it to the computer 10a, a digital input interface 10c that formats the on/off signal of each switch from the switch panel 11 and inputs it to the computer 10a, and a function output from the computer 10a. An amplifier circuit 10d that amplifies the operation command signals of the elements 3, 31 to 36, an information processing clock generation circuit 10e, a constant voltage circuit, and an initialization circuit that starts the operation of the computer 10a immediately after the ignition switch 13 is turned on. (not shown).

FIG. 3 shows the flow of the control program of the computer 10a, and the operation of the apparatus will be explained below with reference to FIG.

First, the arithmetic processing of the microcomputer will be explained. Now in cars equipped with this device,
When the ignition switch 13 is closed, stabilized power is supplied to the microcomputer 10a through the stabilized power supply circuit, and the computer 10a enters the operating state, processing the air conditioner control program of several millimeters in synchronization over several milliseconds. Execute. That is, after initial setting, the microcomputer 10a starts its arithmetic processing at signal input step 101 in FIG. This signal input step 101
Now, analog voltage signals from the inside temperature sensor 21, outside temperature sensor 22, temperature setting device 23, damper 7 opening sensor 24, ventilation opening 40 opening sensor 25, vehicle speed sensor 26, and water temperature sensor 27 are converted to A/
The signals are sequentially converted into digital signals via the D converter 10b and stored in the RAM.

Next, in step 102, the operating state of the switch that commands the operation of the blower motor 3 among the switches on the switch panel 11 is determined, and AC=0.
That is, if there is no command to operate the blower motor, the process proceeds to the next step 103, but if AC=1, that is, if there is a command to operate the blower motor, processing for normally operating the air conditioner is performed. In this normal process, the rotational speed of the blower motor 3, the operation of the heat exchangers 4 and 5, and the opening/closing and opening degrees of the dampers 2, 7, and 8 are determined based on the data input in step 101, and set using the setting device 23. Control is performed to obtain the desired temperature.

If there is no command to operate the blower motor, the step
In step 103, the state of the mode switch of the suction port on the switch panel 11 is determined, and if DI=1, that is, internal air suction is not commanded, the next step is executed.
Proceed to step 104 and return to step 101 when DI=0, the internal air suction mode.

In step 104, an energizing signal for the negative pressure actuator 33 is outputted via the amplifier 10d to drive the inside and outside air damper 2 to open the outside air suction port 1a. Next, in step 105, an energizing signal for the solenoid valve 32 is outputted via the amplifier 10d, and engine cooling water circulates through the heater core 5. At this time, a de-energizing signal of the electromagnetic clutch 31 is output, and if AC=1 and the cooling cycle is being operated by normal processing, it is stopped. This allows the heat exchangers 4 and 5 to perform only heating operations.

Next, in order to determine the air volume W ₂ blown from the ventilation duct 1, first in step 106 the difference ΔT between the vehicle interior temperature Tr and the set temperature Ts is calculated, and in step 107, when ΔT is large, the air volume W ₁ is also increased ΔT. When the air volume W 1 is small, the air volume W ₁ is also reduced, so data of the air volume W ₁ previously set in a matrix format in the ROM is read out using ΔT as an address. Next, step
In steps 108 to 111, in order to determine the opening degree of the ventilation opening adjustment damper 41 so as to obtain the air volume W ₁ , first in step 108, when the ventilation opening adjustment damper 41 is opened to the maximum, the opening degree is determined by the running pressure. The air volume W ₂ MAX generated in the ventilation duct 1 is read out from a preset value in relation to the vehicle speed Vs, and this air volume W 2 MAX is determined as the air volume W ₂ MAX.
If it is larger than W ₁ , in step 110, the opening degree D is calculated in accordance with the air volume W ₁ and the vehicle speed Vs at that time. K ₁ is a constant determined experimentally. Said air volume
If W ₂ MAX is smaller than the required air volume W ₁ , a value DMAX is set in step 111 that makes the degree of opening D fully open.

Next, in step 112, step 110 or
The amplifier 10d compares the actual opening AW with this opening D so that the opening D determined in step 111 is obtained.
The operation of the negative pressure actuator 36 is switched through.

Next, in steps 113 to 119, the set temperature Ts
The opening degree Ar of the A/M damper 7 is determined to obtain the following. First, in step 113, the blowing air temperature necessary to obtain the set temperature Ts when the air volume is W ₂ is determined.
Calculate Tao using the following formula.

Ks＝Ks′・f(W ₂ ) ……(1) Ka＝Ka′・f(W ₂ ) ……(2) Kr＝Kr′・f(W ₂ ) ……(3) C = C′・f(W ₂ )...(4) Tao=Ks・Ts−Ka・Ta−Kr・Tr+C……(5) This formula is generally used to calculate the vehicle heat load, and Ks, Ka, Kr, and C are It is a value related to the air volume W ₂ , ventilation resistance of the ventilation duct 1, etc., and is a function of the air volume W ₂ to the constants Ks', Ka', Kr', C', which are experimentally determined in advance according to equations (1) to (4). Determine by multiplying.

In the next step 114, the engine coolant temperature Tw
Find the maximum blowout air temperature TaoMAX from the outside air temperature Ta, which is the air temperature upstream of the heater, and
In step 115, this TaoMAX is the required blowout temperature Tao
If it is lower, in step 116, the opening degree Ao of the A/M damper 7 is set to the full opening value AoMAX so that the blowing temperature reaches its maximum value. Step 117
If the necessary blowout temperature Tao is lower than the outside air temperature Ta, the process proceeds to step 118 and the opening degree Ao of the A/M damper 7 is set to the fully closed value AoMIN so that the airflow temperature becomes the outside air temperature Ta. If an intermediate outlet temperature between the maximum value TaoMAX and the minimum value (equal to Ta) is obtained, the required outlet temperature is determined in step 119.
Difference between Tao and outside temperature Ta, cooling water temperature Tw and outside temperature
Opening degree Ao of A/M damper 7 as a ratio to the difference from Ta
Calculate.

Next, in step 120, the amplifier 10d is compared with the actual opening Ar so that the damper opening Ao obtained in steps 116, 118, and 119 can be obtained.
The operation of the negative pressure actuator 34 is switched through.

After this step, processes for controlling the opening and closing of the outlet damper 8 and controlling the display operation of the display panel 12 are executed, and the process returns to step 101.

The above-mentioned process is repeatedly executed, and the ignition switch 13 (first switch) is closed.
In addition, when the operation of the blower motor is not commanded by the corresponding switch (second switch) in the switch panel 11 (second position), the computer 1
Processing from step 103 is executed by 0a,
The opening degree of the ventilation port 40 and the opening degree of the A/M damper 7 are appropriately adjusted based on data such as the vehicle interior temperature Tr, and the airflow volume is adjusted to an appropriate value and the vehicle interior temperature Tr is set as much as possible. The temperature is controlled to approach the temperature Ts. Incidentally, when the suction mode is commanded to be internal air mode by the switch panel 11, this control is not carried out, and other prescribed control is carried out.

When the switch panel 11 commands the blower motor to operate (first position), the computer 1
0a executes normal processing from step 102, operates the blower motor 3 and adjusts its rotation speed, activates the heat exchangers 4 and 5 as necessary, and adjusts the opening degree of the A/M damper 7. temperature control. In addition, the inside and outside air damper 2, the outlet damper 8
Controls opening and closing according to the program. Since these normal processes are not the gist of the present invention, their details will be omitted.

When the ignition switch 13 is opened, the computer 10a stops operating and loses all functions as an air conditioner (third position).

Although one embodiment of the present invention has been described above, the present invention may be implemented in the following modified examples.

(1) In an air conditioner in which the upstream side of the ventilation duct communicates only with the outside air suction port, the processing from step 105 onward can be performed without determining whether the outside air suction port is commanded.

(2) The amount of air blown out due to the running pressure of the automobile can be adjusted by adjusting the opening of the rear ventilation opening of the passenger compartment as in the above embodiment, and also by adjusting the opening of the car window or the opening of the inside/outside air damper 2. It can also be adjusted by providing a device that selects the degree appropriately.

(3) In order to more accurately adjust the amount of air blown out, an air amount or wind speed sensor may be provided in the ventilation duct, and the opening degree of the ventilation port may be adjusted based on the detection signal from the sensor.

(4) Adjusting the amount of blown air as described above is effective in maintaining a more stable temperature inside the vehicle, but heat exchangers, etc. should be arranged so that the amount of blown air does not change significantly due to vehicle speed, etc. It is not necessarily necessary if it is done.

For example, in the above embodiment, the heat exchange action of the heater is adjusted by the opening degree of the ventilation port and the opening degree of the A/M damper, but it is also possible to adjust only the opening degree of the A/M damper. good. Further, instead of the A/M damper, an electric control valve or the like that continuously changes the amount of engine cooling water flowing into the heater core 5 may be used.

(5) The control device 10 may have a configuration in which the main part is a digital computer that operates according to a control program, or it may be configured by a combination of circuit groups with predetermined functions. An example is shown in FIG.

In the figure, when the key switch 13 is closed at the ignition position and the blower switch 11a and the air conditioning switch 11b, which are the second switches, are closed, the blower motor 3 is energized and the electromagnetic clutch 31 and the electromagnetic valve 32 are energized to generate heat. Exchanger 4, 5
becomes operational. Furthermore, a known temperature control circuit 51 is activated by power supply through the diode 50 and outputs a temperature control signal. This signal is amplified by an amplifier 52 and A/Med by a negative pressure actuator 34a.
Adjust the opening degree of damper 7. 3a is a variable resistance for adjusting the amount of blown air. Also, 21a
22a is an inside temperature sensor, and 22a is an outside temperature sensor consisting of a heat-sensitive resistor. 23a is a variable resistor for temperature setting, 24
a is a potentiometer that responds to the opening degree of the damper 7. With the above components, the switch 13,
When 11a and 11b are closed, the device performs normal temperature adjustment control. Also, switches 13 and 11a
When closed, only air is blown.

In addition, 53 is a comparator, 54 is a switching transistor, 55 is a normally closed relay, and the temperature control circuit 5
The solenoid valve 32 is deenergized when the temperature control signal No. 1 reaches a value that fully closes the A/M damper 7.

Reference numeral 11c is an outside air interlocking switch that is interlocked with outside air intake. In this example, the present invention is applied to a device for manually operating the inside and outside air damper 2, and the switch 11c is closed when the inside and outside air damper 2 is operated to the outside air suction position. and,
When only the key switch 13 is closed,
Even if the blower switch 11a is open, if the outside air interlocking switch 11c is closed, the control device 10 will adjust the temperature as much as possible.

Reference numeral 56 denotes a known frequency-voltage conversion circuit, which generates a vehicle speed voltage proportional to the number of times per hour that the reed switch 26a opens and closes in synchronization with the rotation of the speedometer cable. A comparator 57 turns on the transistor 54 to energize the normally closed relay 55 and close the electromagnetic valve 32 when the vehicle speed voltage corresponds to the vehicle stop state, thereby stopping the heat exchange action of the heater core 5. A comparator 58 operates the negative pressure actuator 33a via the amplifier 59 when the vehicle speed voltage is, for example, 70 km/h or more, thereby driving the outside air suction limiting damper 2a. This outside air intake limiting damper 2
A is provided upstream of the outside air suction port 1a, and is arranged so as to close the passage by about 30%. That is, when the vehicle speed is, for example, 70 km/h or more, the amount of natural ventilation air generated in the ventilation duct due to the running pressure increases too much, so this is limited.

Thus, when the switches 13 and 11c are closed, the air generated in the ventilation duct due to the running pressure of the vehicle is appropriately heated by the heater core 34 and the A/M damper 7, and the temperature inside the vehicle is maintained. Adjust. When it is necessary to lower the temperature inside the vehicle, the temperature control signal from the temperature control circuit 51 has a value that fully closes the A/M damper 7, so the signal from the comparator 53 turns on the transistor 54 and closes the relay 5.
Since the contact point 5 is opened and the solenoid valve 32 is deenergized, the heat exchange action of the heater core 5 is stopped.

The above operation is performed when the blower switch 11a is closed, the inverter 60 and the AND gate 6
It is partially stopped by the action of 1 and 62. That is, when the blower switch 11a closes, the comparator 5
Since the signals 7 and 58 are not transmitted to the subsequent stages, the external air intake limiting damper 2a and the relay 55 are
is never driven.

As described above, in the present invention, even when the electric blower and cooler are stopped, air conditioning control centered on warming the vehicle interior temperature can be performed, and the power consumption of the electric blower is reduced. This has the excellent effect of reducing the load on the motor vehicle and enabling all-season air conditioning.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram showing an embodiment of the present invention;
2 is a block diagram showing the electrical control system of the device shown in FIG. 1, FIG. 3 is a flowchart showing the control program of the digital computer 10a in FIG. 2, and FIG.
The figure is an electrical wiring diagram partially represented by blocks, showing another embodiment of the present invention. 1...Ventilation duct, 1a...Outside air intake port, 2a
...Outside air suction limiting damper that adjusts the opening of the outside air intake port, 3...Electric blower (blower motor), 4
... Cooler (evaporator), 5 ... Heater (heater core), 7 ... Temperature adjustment damper, 10 ...
Control device, 11, 11a, 11b, 13...Switch panel forming switch means, blower switch, air conditioning switch, key switch, 21, 21
a...Interior temperature sensor for measuring vehicle interior temperature, 31...
Electromagnetic clutch, 32... Solenoid valve, 40... Ventilation port, 41... Ventilation port opening adjustment damper.

Claims (1)

[Scope of Claims] 1. An electric blower, a cooler using the automobile prime mover as a drive source, and an automobile prime mover as a heat source are installed in a ventilation duct whose upstream side is communicated with an outside air intake port and whose downstream side is open into the vehicle interior. and a heater capable of adjusting the amount of heat exchange, and a switch means for operating the device by commanding at least the blowing action by the electric blower and the cooling action by the cooler. In the air conditioner, when the switch means is in a non-command state and outside air is introduced from the outside air suction port, the heater is enabled to perform a heating action, and outside air is introduced into the ventilation duct from the air suction port without using the electric blower. What is claimed is: 1. An air conditioner for an automobile, comprising a control means for adjusting the amount of air heat released into a vehicle interior. 2. The air conditioner for an automobile according to claim 1, wherein the control means includes a feedback control device that adjusts the amount of heat exchange of the heater based on the measured value of the temperature inside the vehicle. 3. The control means includes an opening adjustment mechanism for the outside air intake that adjusts the amount of air introduced from the outside air intake into the ventilation duct according to the driving pressure of the automobile. The automotive air conditioner according to scope 1. 4. The control means controls the amount of air released from the passenger compartment to the outside of the passenger compartment via the ventilation port in order to adjust the amount of air introduced from the outside air intake port into the ventilation duct according to the driving pressure of the vehicle. The air conditioner for an automobile according to claim 1, further comprising a mechanism for adjusting the opening degree of the ventilation port. 5. A first position in which the switch means commands the operation of the electric blower and the cooling action, a second position in which the switch means enables the operation of the control means, and the electric blower, the cooler, and the control means. 2. The air conditioner for an automobile according to claim 1, wherein the air conditioner is configured to be selectable from a third position in which the operation of the air conditioner is completely stopped. 6. When the switch means includes a first switch and a second switch, the first switch selects the second position and the third position, and the first switch is in the second position. 6. The air conditioner for an automobile according to claim 5, wherein the first position can be selected by a second switch.