JPS61291209A - Air conditioner for vehicle - Google Patents

Abstract

PURPOSE:To eliminate discomfort felt by a passenger because of rapid high- speed rotation of a blower fan, by providing a rotational speed increase inhibiting command means for inhibiting an increase in a rotational speed of a motor of the blower fan when a change in a set temperature is detected. CONSTITUTION:A temperature control means b controls a temperature of an induction air so as to attain a target compartment temperature (set temperature) as set by a target temperature setting means (a). The temperature-controlled induction air is blown into the compartment by a blower fan c. a rotational speed of a motor d of the blower fan c is controlled by a motor control means e according to the set temperature. A set temperature change detecting means f is provided to detect a change in the set temperature, and when a change is detected, a rotational speed increase inhibiting command means g generates to feed a command signal for inhibiting an increase in the rotational speed of the motor to be motor control means e.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of the Invention) The present invention relates to a vehicle air conditioner that controls vehicle interior temperature to a set temperature.

(Background of the Invention) Conventionally, in this type of device, the temperature of the introduced air is controlled to a set temperature, and the temperature-controlled introduced air is blown into the vehicle interior by a blower fan (Japanese Patent Application Laid-Open No. 55-1999). 49649).

In the conventional device, the motor drive voltage applied to the blower fan motor is adjusted to the second level depending on the blowing temperature.
It is controlled according to characteristic 100 in the figure, and when the error in the vehicle interior temperature with respect to the set temperature is extremely small, the motor drive voltage is decreased and the blower fan is operated at a low speed (
Stable @it).

Further, as the temperature error increases, the motor drive voltage increases and the blower fan is operated at high speed, thereby quickly controlling the cabin temperature to the set temperature (warm-up region or cool-down region vJ).

However, in conventional devices, when the cabin temperature matches the set temperature and the blower fan is operating at low speed (stable region), when the set temperature is changed, the motor drive voltage is increased and the blower fan suddenly speeds up. There was a problem that the vehicle was being driven and the passengers felt uncomfortable.

(Object of the invention) The present invention has been made in view of the above-mentioned conventional problems, and
The purpose is to provide an air conditioner for a vehicle that can avoid unexpected high-speed operation of a blower fan that causes discomfort to passengers.

(Configuration of the Invention) In order to achieve the above object, an apparatus according to the present invention is configured as shown in FIG.

In the figure, a target cabin temperature is set by the target temperature setting means a, and the temperature of the introduced air is controlled to the set temperature by the temperature control means.

The temperature-controlled introduced air is the blower fan C.
The motor d of the blower fan C is controlled by the motor control means e to a rotation speed corresponding to the set temperature.

Further, a change in the set temperature is detected by the set temperature change detection means f, and when the change is detected, the motor control means e is commanded to prohibit an increase in the motor rotation speed from the rotation speed increase prohibition command means q. ing.

(Description of Embodiments) Hereinafter, preferred embodiments of the apparatus according to the present invention will be described based on the drawings.

In Fig. 3, outside air flows from the intake port 10,
Inside air is taken in from 2 to each inlet 14, and the intake air is switched by operating an inside/outside air switching door 16.

The intake air is then taken into the inlet port 1 by the blower fan 18.
4 into the apparatus, and the blower fan 18 is driven by a motor 20.

Further, the introduced air is cooled by the evaporator 22, and only the amount of the cooled air determined by the opening degree of the air mix door 24 is heated by the heater core 26.

This heated air and cooling air are mixed to obtain air at a set temperature, and the mixed air is supplied to the outlet 28.30.3.
2 is being blown into the passenger compartment.

Further, the opening degree of the air mix door 24 is adjusted by an actuator 34, which is controlled by a solenoid valve 36 that guides the negative pressure of the engine intake pipe and a solenoid valve 38 that opens to the atmosphere.

The doors of the air outlets 28, 30, 32 are driven to open and close by actuators 40, 42, 44, and these actuators 40, 42, 44 are driven by a solenoid valve 46.
．． 48.50, respectively. The refrigerant vaporized in the evaporator 22 is compressed by the compressor 52, and the air mix door 24 is compressed by the compressor 52.
The opening degree of is detected by a sensor 54.

The intermediate detection signal is sent to the A/D converter circuit 56 in
The A/D conversion circuit 56 is provided with a sensor 58. which detects the temperature inside the vehicle. Sensor 60 for detecting the temperature of introduced air. Each detection signal of a sensor 62 that detects the temperature of the outside air and a temperature setting signal of a temperature setting device 64 are provided.

These signals converted into digital signals by the A/D conversion circuit 56 are given to a control circuit 66 mainly composed of a microcomputer.
Solenoid valve 36.38.46,48,50
and motor 20 are controlled.

The motor 20 is driven by a driver 68, the solenoid valves 36.38 are driven by a driver 70, and the solenoid valves 46, 48.50 are driven by a driver 72. A converters 74 and 76 are provided.

FIG. 5 shows a flowchart of the control procedure of the control circuit 66, and the process of FIG. 5 is repeatedly performed at a predetermined period.

In the process of FIG. 5, the sensors 54, 58°60.6
The opening degree of the air mix door 24, the temperature inside the vehicle, the temperature of the introduced air, and the temperature of the outside air detected in step 2.

Then, the target seedling temperature set by the temperature setting device 64 is first read (step 200>).

The set temperature TpTC of the temperature setting device 64, the outside air temperature TA detected by the sensor 62, and the vehicle interior temperature TF detected by the sensor 58? and constants A, B, C, D
The target blowout temperature To is determined using (step 202>), and the calculation is shown by the following equation.

To=A-TPTC+B-TA+C・(TPTC-TR
>+D When the target blowout temperature To is determined in this way,
The temperature of the cooling air on the downstream side of the evaporator 22 is estimated according to the procedure shown in FIG. 6 (step 204).

In the process shown in FIG. 6, it is first determined whether or not the compressor 52 is in operation (step 206), and when it is determined that the compressor 52 is not in operation, the temperature of the introduced air detected by the sensor 60 is TlN0 is assumed to be the estimated temperature TIN.

Further, when it is determined that the compressor 52 is in operation, a temperature TIN+ is obtained by subtracting 2Q°C from the detected temperature TlNa (step 210>, and whether the temperature Tr~1 exceeds 5°C is determined). It is determined whether or not (
Step 212).

At that time, if it is determined that the temperature TIN+ exceeds 5°C, the temperature TrN1 is set as the estimated temperature TIN (step 214>, and if it is determined that the temperature TrNt is below 5°C) Estimated temperature TIN when performed
is set to 5° C. (step 216).

When the cooling temperature TIN is estimated based on the operating state of the compressor 52 and the temperature immediately before the evaporator 22 in step 204 above, the target opening degree of the air mix door 24 is determined using the estimated temperature TIN (the fifth
Figure Step 218) When calculating this opening degree, as shown in Figure 7, the target blowout temperature T-
A target variation X characteristic is prepared, and the target opening degree X is determined from the characteristic of the estimated temperature TIN at that time using the target blowout temperature To determined by the above equation.

After that, the actual opening detected by the sensor 54 is the target opening
The opening deviation is obtained by subtracting it from (step 220)
, a control signal corresponding to the deviation is output, and the opening degree of the air mix door 24 is controlled to the target opening degree X.

As a result, the cooling air of the evaporator 22 and the heater core 26
The heated air is mixed with the heated air at a rate determined by the opening degree of the air mix door 24, and therefore, the air blown into the single room is controlled to the target set temperature To.

As described above, the temperature of the air blown into the vehicle interior is controlled to the set temperature TPTC. At this time, the air outlet mode is determined according to the characteristics shown in FIG. 8 (step 224>, and the air outlet 30 is .32 door is controlled to open and close (step 226).

Next, the motor 20 of the blower fan 18 is controlled as follows (step 228).

FIG. 9 shows the processing procedure for motor control. First, the set temperature TPT from the previous processing to the present
The amount of change in C is determined (step 230).

Then, it is determined whether or not the change has been made based on the amount of change in the set temperature TPTC (step 232>; if it is determined that the change has not been made, the flag is reset; When it is determined that the flag has been set, each flag is set (steps 234 and 236>).

Furthermore, when the motor drive voltage is calculated according to the characteristic 100 of FIG. 2 (step 238), it is determined whether a flag has been set (step 240).

At that time, if it is determined that the flag has not been set and no change in the set temperature TPTC is confirmed, the motor drive voltage obtained in step 238 of the current processing cycle is set as the output voltage (step 242). ), the voltage is applied to the motor 20 to perform motor control (step 244).

Furthermore, when it is determined that the flag has been set and a change in the set temperature TPTC is confirmed, it is determined whether the calculated voltage in the current processing cycle has increased with respect to the calculated voltage in the previous processing cycle ( step 246)
When it is determined that the motor drive voltage has not increased, the calculated voltage in the current processing cycle is set as the output voltage (step 248>, and the voltage is output to the motor 20 (step 244>).

On the other hand, when it is determined that the motor drive voltage increases from the previous processing cycle, the motor drive voltage calculated in the previous processing cycle is set as the output voltage, and the same voltage as in the previous processing cycle is output to the motor 20. (step 244).

As described above, when a change in the set temperature TPTC is not confirmed, the motor drive voltage is controlled in the same way as in the conventional case, and the motor 20 of the Heblower fan 18 is controlled at a rotation speed according to the set temperature subcutaneous PTC.

Further, even if there is a change in the set temperature TPTC, if the motor drive voltage does not increase, the rotation speed of the motor 20 is controlled to the rotation speed determined by the motor drive voltage determined at that time.

Furthermore, when there is a change in the set temperature TPTC and the motor drive voltage increases, the motor drive voltage output to the motor 20 is set to that in the previous processing cycle,
This prohibits the rotation speed of the motor 20 (blower fan 18) from increasing.

As explained above, according to the present embodiment, when a change in the set temperature TPTC is detected, an increase in the rotation speed of the motor 20 is prohibited, so that the motor rotation speed can be suddenly increased by the operation of changing the set temperature TPTC. It will not rise to .

For this reason, when the vehicle interior temperature almost matches the set temperature and the blower fan 18 is operated at low speed, even if the set temperature subcutaneous PTC is changed in order to slightly adjust the vehicle interior temperature, the blower fan 18 The rotational speed of the engine will not increase unexpectedly, and therefore will not cause discomfort to the occupants.

(Effects of the Invention) As explained above, according to the present invention, when a change in the set temperature is detected, the blower fan motor rotation speed is prohibited from increasing, so that the floor fan rotation speed does not suddenly increase. Therefore, it does not cause any discomfort to the occupants.

[Brief explanation of the drawing]

Fig. 1 is a diagram corresponding to complaints, Fig. 2 is a motor drive voltage calculation characteristic diagram, Fig. 3 is an explanatory diagram of the arrangement position of each member in the air flow path, and Fig. 4 is a preferred embodiment of the device according to the present invention. 5 and 6 are flowcharts explaining the processing procedure of the control circuit in FIG. 4,
FIG. 7 is a characteristic diagram for calculating the opening degree of the air mix door, FIG. 8 is a characteristic diagram for determining the blowing mode, and FIG. 9 is a flowchart explaining the processing procedure of the control circuit in FIG. 4. a...Target temperature setting means b...Temperature control means C...Blower fan d...Motor e...Motor control means f...Set temperature change detection means q...Rotational speed increase prohibition command Means 14...Inlet 18...Blower fan 20...Motor 22...Evaporator 24...Air mix door 26...Heater core 36.38, 46, 48.50...Solenoid valve 54. 58, 60, 62...Sensor 64...Temperature setting device 66...Control circuit Patent applicant Nissan Motor Co., Ltd. Figure 6Figure 7X ・3σC ・2σC =10'C

Claims (1)

[Claims] (1) A target temperature setting means for setting a target vehicle interior temperature, a temperature control means for controlling the temperature of introduced air to a set temperature, a blower fan that sends the temperature-controlled introduced air into the vehicle interior, and a blower fan. a motor control means for controlling the motor to a rotation speed according to a set temperature; a set temperature change detection means for detecting a change in the set temperature; and a set temperature change detection means for detecting a change in the set temperature; An air conditioner for a vehicle, comprising: a rotation speed increase prohibition command means for commanding a motor control means.