JPH0144525B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a vehicle air conditioner, and more specifically, a vehicle air conditioner that determines the heating capacity when heating is started and controls the amount of air blown. Regarding equipment.

(Prior Art) Conventionally, in vehicle air conditioners that perform this type of airflow control, the heating capacity is controlled by the airflow rate from the blower, as shown in Japanese Patent Laid-Open No. 56-146416, for example. In some systems, for example, when maximum heating is required, the blower is controlled to the maximum air flow rate regardless of the engine coolant temperature.

(Problem to be Solved by the Invention) In the conventional system as described above, the maximum air flow rate in the automatic control state is controlled regardless of the engine coolant temperature. The air flow rate was controlled at or near the maximum value in order to bring the temperature closer to the set temperature.

Therefore, if the heating capacity of the heater unit is not sufficient, there is a problem in that the temperature of the air blown into the passenger compartment is lowered, and the temperature of the passenger compartment is also lowered.

Further, there is a problem in that the temperature of the air blown into the vehicle compartment decreases due to the difference in the increase in the temperature of the engine coolant depending on the engine type, as described above. For example, in the case of diesel engines, the difference is remarkable. Furthermore, even if the engine coolant temperature has reached its upper limit, there is a problem that depending on the engine type, the heating capacity may be insufficient at low outside temperatures.

(Means for Solving the Problems) In order to solve the above problems, the present invention is constructed as shown in FIG. 1.

A blowing means 1 for blowing air into the vehicle interior 30 via a heat exchange means 2 including a heating means using engine cooling water as a heat source, a vehicle interior temperature detection means 3, a vehicle interior temperature setting means 4, and at least a detection vehicle a calculation means 5 for calculating a vehicle interior temperature control signal related to the deviation between the interior temperature and a set vehicle interior temperature; and a control means 6 for controlling the air blowing amount of the ventilation means 1 based on the calculated vehicle interior temperature control signal. In the vehicle air conditioner, the maximum value detection means 7 detects the maximum value of the engine cooling water temperature, and the maximum air flow rate of the air blowing means 1 during the heating state is limited according to the maximum engine cooling water temperature. and restriction means 3.

(Function) The amount of air blown by the air blowing means 1 is determined based on the calculated vehicle interior air temperature control signal calculated by the calculating means 5.
For example, it is controlled by a predetermined pattern. The controlled air from the air blowing means 1 is blown into the vehicle compartment 30 through the heat exchange means 2. However, during the heating state, the air blown from the air blowing means 1 is heated by the heating means in the heat exchange means 2 and blown into the vehicle compartment 30.

On the other hand, the maximum value of the engine cooling water temperature is detected by the maximum value detection means 7, and as the engine cooling water maximum temperature reaches the maximum value, the air blowing means 1 during the heating state is detected.
The maximum amount of air blown is limited by the limiting means 8.

As a result, the maximum amount of air blown from the air blowing means 1 is limited when the maximum engine cooling water temperature is low during the heating state, so that the maximum amount of air blown to the passenger compartment 30 is limited when the maximum engine cooling water temperature is low. It will no longer be blown into the vehicle and will no longer cool the interior of the vehicle.

Further, by limiting the maximum amount of air blown during the heating state in accordance with the maximum value of the cooling water temperature, it is possible to cope with differences in engine types.

(Example) The present invention will be explained below with reference to Examples.

FIG. 2 is a block diagram showing the configuration of a vehicle air conditioner according to an embodiment of the present invention.

21 is an air conditioner main body, and 22 is a control device that controls the air conditioner main body 21.

The air conditioner main body 21 has an intake damper 2 arranged from the upstream side to the downstream side of the duct 23, which selects whether the intake air is to be air inside the vehicle or outside.
4. A blower 25 that blows the air sucked in through the intake damper 24 into the vehicle compartment 30, an evaporator 26 that exchanges heat with the blown air while the cooler 34 (described later) is in operation, and a heater 28 (described later) in the air that has passed through the evaporator 26. A mix damper 27 that controls the amount of air to be diverted, a heater core 28 that circulates the cooling water of the vehicle internal combustion engine and acts as a heater to heat the passing air, and a mode switching damper 29 that selects the air outlet to the vehicle interior 30. We are prepared.

The compressor 35, condenser 36, receiver tank 37, and expansion valve 38 together with the evaporator 26 constitute a cooler 34. Furthermore, the rotation of the output shaft of the vehicle-mounted internal combustion engine is transmitted to the pulley 39. The rotation of the pulley 39 is controlled by the magnetic clutch 4.
0 to the compressor 35, and this transmission drives the compressor 35.

The air outlet to the vehicle interior 30 is formed by a vent outlet 31 that blows air toward the occupant's face, and a heat outlet 32 that blows air from the feet.
One or both of them are selected by the mode switching damper 29.

The intake damper 24 is driven by a motor actuator 33, the mix damper 27 is driven by a motor actuator 41, and the mode switching damper 29 is driven by a motor actuator 42. In addition, in FIG. 2, 44 to 48 are the motor actuator 33, the blower 25, the magnetic clutch 40, and the motor actuator 4, respectively.
1 and 42, respectively.

On the other hand, an inside air temperature sensor 50 that detects the indoor air temperature of the vehicle, a solar radiation sensor 51 (with a photoelectric conversion element as a detection end) that detects the amount of solar radiation, and an evaporator outlet air temperature that detects the evaporator exit air temperature, that is, the temperature at point A. A sensor 52, an outside air temperature sensor 53 for detecting the outside air temperature, a setting device 54 for setting the vehicle interior temperature, a potentiometer 55 for detecting the mix damper opening degree, and an engine cooling water temperature sensor 56 for detecting the engine cooling water temperature are provided. be.
The output of each sensor, the output of the setting device 54 and the output of the potentiometer 55 are supplied to an A/D converter (hereinafter referred to as ADC) 58 via a multiplexer 57 and converted into digital data.
The digital data converted in is supplied to a microcomputer 59.

The microcomputer 59 is basically a CPU,
It has a ROM that stores programs, a RAM that stores data, an input port, an output port, and a timer. According to the program stored in the ROM, the output digital data from the ADC58 is read through the input port and sent to the CPU.
The data processed and calculated is outputted to the drive circuits 44 to 48 via the output ports, and is used to control the amount of air blown by the blower 25, the operating timing and period of the compressor controlled via the magnetic clutch 40, and the opening degree of the mix damper 27. Control is performed so that the temperature inside the vehicle is controlled to the temperature set by the setting device 54. Note that the description will be made assuming that the intake damper is manually designated to circulate internal air or take in external air.

The operation of one embodiment of the present invention will be explained with reference to the flowchart of FIG. 3 in accordance with the program stored in the ROM.

When the program starts running, initial settings such as clearing the RAM are performed (step a).
Next, the outputs of the sensors 50 to 53 and 56, the output of the setting device 54, and the output of the potentiometer 55, which are converted into digital data via the input ports, are read, temporarily stored in a predetermined area of the RAM, and then stored in the vehicle interior. Air temperature control signal (hereinafter referred to as integrated data) T=T _R +K ₁ T _E +K ₂ T _A +K ₃ T _S −
K ₄ T _D +K ₅ is calculated and stored (step b). Here, _TR represents the inside air temperature, T _E represents the evaporator outlet air temperature, T _A represents the outside air temperature, and T _S represents the amount of solar radiation, which are detected by the sensors 50 to 53. T _D is the set temperature set by the setting device 54, and K ₁ to K ₅ are constants. Further, T _W described later is the engine coolant temperature (hereinafter simply referred to as the coolant temperature). Therefore, the integrated data T is related to the deviation between the set vehicle interior temperature and the detected interior temperature, and also corresponds to a value corrected by the evaporator outlet air temperature T _E , the amount of solar radiation T _S , and the outside air temperature T _A. It can also be said to be a value related to the heat load for controlling the indoor temperature to the set vehicle indoor temperature.

Following step b, the air blowing amount of the blower 25 is controlled according to a preset control pattern in accordance with the total data T as shown in FIG. 4a (step c). As will be described later (FIG. 5), the maximum amount of air blown is limited during heating.

Following step c, the opening degree of the mix damper 27 is controlled according to a preset control pattern corresponding to the total data T as shown in FIG. 4b (step d). Following step d, the drive set temperature of the compressor 35 is controlled according to a preset control pattern in accordance with the total data T as shown in FIG. 4c (step e). In step e, when the evaporator outlet air temperature _T is higher than the temperature pattern shown in FIG. 4c, the magnetic clutch 40 is energized to drive the compressor 35, and when it is below the temperature pattern shown in FIG. Compressor control is performed in which the magnetic clutch 40 is de-energized. By steps d and e, the vehicle interior temperature is controlled to the set vehicle interior temperature.

Following step e, data T _F =T _E +K ₆ θ+β
is calculated and stored (step f). Here, θ indicates the opening degree of the mix damper 27,
The opening degree when all the air passing through the evaporator 26 passes through the heater core 28 is θ=100.
% (full heat). Furthermore, K ₆ and β are constants. Therefore, data T _F is vehicle compartment 3.
It corresponds to the temperature of the air blown out to 0. Following step f, blowout mode control is performed to select the vent outlet 31 and/or the heat outlet 32 in accordance with the data T _F (step g).
Following step g, step b is executed again. Note that the intake damper 24 is excluded from the flowchart in FIG. 3 because it is controlled to an outside air introduction state or an inside air circulation state according to the output of a manual switch (not shown) whose output is supplied to the microcomputer 59. .

The air flow rate control shown in step c is as shown in the flowchart of FIG.

The engine coolant temperature T _W0 detected by the temperature sensor 56 when the key switch is turned to the ignition on position is initialized to be stored as the coolant temperature T _W and T _W1 , and the detected coolant temperature will be set as T W from the next time onwards. Perform initial setting as _W1 (currently detected cooling water temperature) (step _c1 ). Following step _c1 , it is determined whether a blower switch (not shown) whose output is supplied to the microcomputer 59 is on or off (step _c2 ), and when the blower switch is in the off state, the blower 25 is controlled to be in a stopped state. (Step _c3 ). When it is determined that the blower switch is in the on state, it is determined whether an automatic blower control instruction switch (not shown) whose output is supplied to the microcomputer 59 is on or off (step _c4 );
When it is determined that the automatic blower control instruction switch is in the OFF state, the blower 25 is manually controlled (step _c5 ). When it is determined that the blower automatic control instruction switch is in the on state, following step _c4 , it is determined whether or not the heating state is in effect (step _c6 ). That is, when the blower switch is on and the blower automatic control instruction switch is instructing automatic control, it is determined whether or not the heating state is present. Whether or not the heating state is present can be determined based on the value of the combined data T, and when the combined data T is negative by the setting of the constant _K5 , it is determined that the heating is being performed.

When the heating state is determined in step c ₆ , it is detected whether the currently detected cooling water temperature T _W1 is greater than the previously detected cooling water temperature T _W (step c ₇ ), and if the temperature T _W1 > T _W is determined. When the temperature T _W1 is the temperature
T _W (step c ₈ ). step c ₇
When temperature T _W1 >temperature T _W is not satisfied, step _c8 is bypassed. Therefore, in steps _c7 and _c8 , the maximum value of the cooling water temperature up to that point is detected (step _c9 ).
It is determined whether or not the cooling water temperature detected in step _c9 exceeds a predetermined temperature E degrees (step _c10 ).

Here, the temperature E degree is a value determined by experiment,
It is set to a value that can be reached even in the engine with the lowest increase in coolant temperature among various engines.

In step _c10 , the cooling water temperature T _W becomes the temperature E
If the temperature exceeds the temperature T _W , the drive voltage to be applied to the drive motor of the blower 25 corresponding to the cooling water temperature T W is selected according to the control pattern written in the frame and stored (step c ₁₁ ). ). Following step _c11 , the drive voltage stored in step _c11 is used instead of the maximum drive voltage during heating (step _c12 ). Therefore, the maximum drive voltage during heating varies depending on the cooling water temperature according to the broken line in the frame of step _c11 [the broken line in Fig. 4a (note that Fig. 4a is shown in terms of the air flow rate]). In addition, if it is determined in step _c6 that the heating state is not present, step _c12 is executed immediately from step _c6 , so that the driving voltage of the blower 25 is changed according to the total data T. will not be restricted.

Also, in step _c10 , the cooling water temperature T _W is E
If the temperature is _below
The voltage applied to the drive motor is set to G (V) (step _c13 ), and this voltage G (V) is set as the maximum drive voltage when T _W >E (step c13).
_c12 ). Therefore, the maximum drive voltage applied to the drive motor of the blower 25 during heating is limited according to the cooling water temperature T _W with G (V) being the minimum voltage.

(Effects of the Invention) As explained above, according to the present invention, the maximum value of the engine cooling water temperature is detected, and the maximum air flow rate during heating is limited in accordance with this maximum value. By setting this setting, the maximum heating effect corresponding to the heater unit's capacity can be brought out, and when the heating capacity of the heater unit is not sufficient, a large amount of air is blown and the temperature of the air blown into the passenger compartment decreases. There will be no more problems.

Furthermore, since the maximum amount of air blown during heating is limited in accordance with the maximum value of the cooling water temperature, it is possible to cope with differences in engine types.

[Brief explanation of drawings]

FIG. 1 is a functional block diagram showing the configuration of the present invention.
FIG. 2 is a block diagram showing the configuration of an embodiment of the present invention. 3 and 5 are flowcharts for explaining the operation of one embodiment of the present invention. FIG. 4 is a diagram for explaining the operation of one embodiment of the present invention. 1... Air blowing means, 2... Heat exchange means, 3... Vehicle interior temperature detection means, 4... Vehicle interior temperature setting means, 5
...Calculating means, 6...Controlling means, 7...Maximum value detection means, 8...Limiting means, 30...Car interior.

Claims (1)

[Scope of Claims] 1. A blowing means for blowing air into the vehicle interior through a heat exchange means including a heating means using engine cooling water as a heat source, a vehicle interior temperature detection means, a vehicle interior temperature setting means, and at least A calculation means for calculating a vehicle interior temperature control signal related to a deviation between a detected vehicle interior temperature and a set vehicle interior temperature, and a control means for controlling an air blowing amount of the ventilation means based on the calculated vehicle interior temperature control signal. A vehicle air conditioner comprising: maximum value detection means for detecting a maximum value of engine cooling water temperature;
1. A vehicular air conditioner, comprising: limiting means for limiting the maximum air flow rate of the air blowing means during a heating state in accordance with the maximum temperature of engine cooling water. 2. Claim 1, characterized in that the limiting means is a limiting means that limits the maximum amount of air blowing means to a lower value as the maximum engine cooling water temperature decreases.
Vehicle air conditioner as described in .