JP2594602B2 - Vehicle air conditioner - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an air conditioner installed in a vehicle,
In a so-called auto air conditioner that automatically adjusts the temperature in the passenger compartment to a comfortable temperature,
The present invention relates to a measure for compensating for a decrease in comfort due to switching of outside air.

2. Description of the Related Art Conventionally, this type of auto air conditioner has been widely and generally well-known. For example, as shown in Japanese Patent Application Laid-Open No. 61-44015, an air conditioner is provided with an air conditioner for adjusting the temperature of air blown into a vehicle compartment. By providing a mix door and controlling the opening degree of the air mix door based on a function value calculated based on environmental conditions inside and outside the vehicle such as a room temperature, an outside air temperature, an amount of solar radiation, a target temperature, etc. This automatically adjusts the temperature of the air blown into the vehicle compartment to the set comfortable temperature.

(Problems to be Solved by the Invention) By the way, in the above-described air conditioner, when the air is heated, the humidity of the air in the passenger compartment is high, and when the high humidity air is circulated, fogging occurs in the window glass. ,
An outside air introduction mode is adopted in which outside air that is dryer than the air in the vehicle compartment is introduced into the air conditioning unit. On the other hand, at the time of cooling, a circulation mode in which the inside air is sucked into the air conditioning unit and blown back into the vehicle compartment is adopted in order to increase the cooling efficiency.

However, in addition to the case where the air introduction mode is automatically selected in response to such cooling / heating switching, there is a situation in which the occupant switches between the inside air and the outside air by manual operation. For example, when operating in outside air introduction mode during heating,
When there is an unpleasant odor in the outside air, the mode is temporarily switched to the circulation mode. In that case, the air introduced into the air conditioning unit is switched from cold outside air to warm outside air, and the air outlet temperature temporarily changes from the comfortable temperature to the set opening of the air mix door, and as a result, However, there was a problem that the occupants felt uncomfortable.

Therefore, it is an object of the present invention to provide an air-conditioning unit that blows air from an air-conditioning unit even when there is a manual operation to switch between inside air and outside air during operation in an auto mode in which the opening of an air mix door is automatically controlled. It is an object of the present invention to suppress the change in the air temperature to be caused, to eliminate the uncomfortable feeling of the occupant, and to maintain the original function of the auto air conditioner to maintain the indoor temperature at a comfortable temperature.

(Means for Solving the Problems) In order to achieve this object, in the present invention, the temperature of the air taken into the air conditioning unit is calculated based on the selected mode, and the air mix is calculated based on the temperature of the intake air. The opening of the door is corrected from the set value.

That is, as shown in FIG. 1, the present invention provides, as shown in FIG. 1, an inside air suction port 7 for sucking air inside the vehicle into the air conditioning unit 1, an outside air suction port 6 for sucking air outside the vehicle into the air conditioning unit 1, and both of these suction ports. An inside / outside air switching means 8 provided downstream of the inside / outside air switching means 8 for changing a ratio of air suction from each of the suction ports 6, 7 based on an operation of a suction mode switching unit by an occupant. The evaporator 12 provided on the side, the heater 19 provided in one of the intake air passages branching downstream of the evaporator, and the air inflow rate into the intake air passage provided with the heater 19 are changed to change the vehicle interior. An air mix door 28 for adjusting the temperature of the air blown to the vehicle, environmental condition detecting means 52 to 54 for detecting environmental conditions inside and outside the vehicle, including at least the air temperature inside and outside the vehicle, and detection of the environmental condition detecting means 52 to 54. Based on the results, A vehicle air conditioner provided with a control means 57 for controlling the door 28 is premised.

Then, based on the mode determining means 58 for detecting the operating state of the inside / outside air switching means 8, the temperature inside and outside the vehicle cabin detected by the environmental state detecting means 52 to 54, and the determination result by the mode determining means 58. A heater inlet air temperature calculating means 59 for calculating the inlet air temperature of the heater 19; andthe control means 57 calculates a result of the heater inlet air temperature calculating means 59 and a result of the environmental state detecting means 52 to 54. , And the air mix door 28 is controlled based on the target temperature in the passenger compartment set by the occupant.

(Operation) With the above configuration, in the present invention, the operation state of the inside / outside air switching means 8 that changes the air intake ratio of each of the inside air and the outside air from each of the intake ports 6 and 7 based on the operation of the intake mode switching unit by the occupant is set In the heater inlet air temperature calculating means 59, the inlet air temperature of the heater 19 is detected based on the determination result by the mode determining means 58 and the temperatures inside and outside the vehicle cabin detected by the environmental state detecting means 52 to 54. The temperature is calculated. Then, the control means 57 controls the air mix door 28 based on the calculation result of the heater inlet air temperature calculation means 59, the detection results of the environmental state detection means 52 to 54, and the target temperature in the vehicle interior set by the occupant. Is controlled.

In this way, the inlet air temperature of the heater 19 is based on the operating state of the inside / outside air switching means 8 determined by the mode determining means 58 and the temperatures inside and outside the vehicle cabin detected by the environmental state detecting means 52 to 54. The air mix door 28 is controlled based on the calculated air temperature at the inlet of the heater.
When the intake air is switched from inside air to outside air or from outside air to inside air and the intake air temperature temporarily changes, the opening of the air mixing door 28 changes the intake air temperature accordingly. That is, when the intake air temperature decreases, the blowout temperature is increased, and when the intake air temperature rises, the blowout temperature is adjusted to be low. Therefore, regardless of whether the intake air is switched between inside and outside air,
Air at a comfortable temperature is always blown out from the air conditioning unit 1,
The occupants do not feel uncomfortable and the comfort can be improved.

Further, since the opening degree of the air mix door 28 is controlled based on the inlet air temperature of the heater 19, the air mixing door 28 passes through the heater 19 as compared with the case where the opening degree of the air mix door 28 is controlled regardless of the heater inlet air temperature. The ratio of the conditioned air can be set to an appropriate value, and air at an appropriate temperature can always be blown from the air conditioning unit 1. That is, the temperature of the air drawn into the air conditioning unit 1 is different from the temperature immediately after the suction due to contact with the blower 5 and the passage wall while passing through the air passage in the air conditioning unit 1. Therefore, if the opening degree of the air mix door is controlled based on the air temperature immediately after the suction, regardless of the heater inlet air temperature, the outlet temperature of the air conditioning unit becomes unstable. However, in the present invention, this can be avoided. it can.

Further, the inlet air temperature of the heater 19 is determined based on the operation result of the inside / outside air switching means 8 by the mode determination means 58 based on the result of the determination as to whether the inside air or the outside air is being introduced. It is not necessary to provide a temperature sensor at the inlet of the heater 19 for directly detecting the air temperature.

(Embodiment) Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

FIG. 2 shows an overall configuration of a vehicle air conditioner according to an embodiment of the present invention, wherein 1 is an air conditioner unit composed of blower, cooler and heater units 2, 10, and 17, and the blower unit 2 is A blower 5 driven by a blower motor 4 is provided in the case 3. The cooler unit 10 is provided with a case 11 connected to the case 3 of the blower unit 2.
The case 11 has an evaporator 12 (evaporator)
Is installed. The evaporator 12 includes an expansion valve (not shown), a compressor 13 (compressor) drivingly connected to an on-vehicle engine 35 via an electromagnetic clutch 13a, a receiver tank 14 and a condenser 15 (condenser) via a refrigerant pipe 16. The refrigerant is circulated between these devices 12-15, and the refrigerant compressed by the compressor 13 is condensed and liquefied by the condenser 15, and the liquid refrigerant is expanded by the expansion valve. By vaporizing, the air is cooled by the heat of vaporization.

Further, the heater unit 17 has a case 18 connected to the case 11 of the cooler unit 10, and a heater core 19 (heater) is mounted in the case 18. The heater core 19 is communicated with a water jacket (not shown) of the engine 35 through a cooling water pipe 20, and supplies the heated cooling water from the engine 35 to the heater core 19 to radiate heat there. It is designed to heat the intake air.

The case 3 of the blower unit 2 has an outside air inlet 6 (outside air inlet) communicating with the outside of the vehicle and an inside air inlet 7 (inside air inlet) communicating with the vehicle interior.
An inside / outside air switching door 8 for selectively switching and introducing outside air or inside air into the case 3 is rotatably supported on the intermediate case 3, and the door 8 is switched by an inside / outside air switching motor 9. Is done.

The case 18 of the heater unit 17 is provided with vent and differential communication ports 21 and 22 and a heat outlet 23, and the heat outlet 23 is opened toward the feet of the occupant. On the other hand, vent communication port 21 has vent duct 24
Are formed at the downstream end of the duct 24. Seven vent outlets 25 are formed in the left-right direction and open toward the chest of the occupant. An upstream end of a differential duct 26 is connected to the differential communication port 22, and four differential outlets 27, 27,... ing.

Further, an air mix door 28 for adjusting the temperature of the air blown into the vehicle interior and an auxiliary door 29 are rotatably supported on the case 18 of the heater unit 17 so as to be rotatable.
Is driven and connected to the mix door motor 30, and controls the opening degree of the air mix door 28, that is, the flow path area with respect to the heater core 19, to adjust the blown air temperature.

The case 18 of the heater unit 17 has a vent door 31 for opening and closing the vent communication port 21, and a differential communication port 22.
A differential door 32 for opening and closing the door and a heat door 33 for opening and closing the heat outlet 23 are rotatably supported.
Numerals 31 to 33 are drivingly connected to a mode door motor 34, and the opening and closing of each of the doors 31 to 33 is controlled by the motor 34 in a predetermined pattern to switch the blowing mode.
The opening and closing of the doors 8, 28, 29, 31-33 are controlled by the motors 9, 30, 34, so that the inside air or outside air sucked into the blower unit 2 is cooled and heated by the cooler unit 10 and the heater unit 17, respectively. After that, the air is blown into the vehicle cabin, and the air in the vehicle cabin is adjusted to a comfortable state.

In the figure, 36 is the central three vent outlets 25, 25,
Reference numeral 37 denotes a swing louver motor provided for driving the swing louver. Reference numeral 38 denotes a radiator disposed immediately behind the condenser 15, 39 denotes a fan driven by the engine 35, and 40 denotes a fan shroud.

The blower motor 4, the motors 9, 30, 34 for opening and closing the doors 8, 28, 29, 31 to 33, the swing louver motor 37 and the electromagnetic clutch 13a are a control unit 50 having a built-in CPU.
The operation is controlled by the following. The control unit 50 is connected to an operating device 51 for instructing an air-conditioning state such as a temperature of the air blown into the vehicle compartment, a blowing amount (air volume), a blowing direction, and the like. A group output signal is input. That is, the operation device 51 includes an auto mode setting unit 51a that switches the operation mode of the air conditioner to the auto mode,
A manual mode switching unit 51b for selectively switching the air conditioner to each of the vent, bi-level and heat modes, and an intake mode switching unit 51c for switching the air intake mode to the air conditioning unit 1 to the circulation mode (REC mode) or the outside air introduction mode. And a temperature setting section 51d for setting a target temperature in the vehicle compartment
And an air volume setting unit 51e for setting the air volume (blowing air volume) of the blower 5, and a display unit 51f for displaying an operation mode of the air conditioner.
Are provided.

On the other hand, the sensor group includes a room temperature sensor 52 (inside air sensor) that detects a temperature tr (room temperature) in the vehicle compartment 2, an outside air sensor 53 that is provided at a front end of an engine room of the vehicle and detects an outside air temperature ta, An insolation sensor 54 disposed on the instrument panel for detecting the amount of insolation, a water temperature sensor 55 for detecting the temperature of the cooling water in the heater core 19, and the air mixing door 28 based on the operation state of the mixing door motor 30, 29
And a potentiometer 56 for detecting the actual opening of the motor.

Then, the CPU of the control unit 50 executes signal processing according to the control flow shown in FIG. That is, it is determined in step S ₁ after a start, whether circulation mode (REC mode) is selected as the current operation mode. Now it is determined YES, the process proceeds to step S _2, the process proceeds to blower inlet temperature t flowing into the evaporator 12 as a room temperature tr in (t = tr) Step S _4. Further, when the determination is NO, the process proceeds to step S ₄ after the routine proceeds to step S ₃ and the blower suction temperature t and the outside air temperature ta (t = ta). In step S _4, and determines whether the cooler unit 10 is set to air-ON state operation, when the determination is NO, the temperature te the blower suction temperature t of the evaporator 12 proceeds to step S ₅ to contrast, when the result is YES, the same evaporator temperature te proceeds to step S ₆ and 0 ° C., then, respectively proceeds to step S _7. In step S _7, and calculates a difference Delta] t = t-te between the blower inlet temperature t and the evaporator temperature te, as the intake air temperature in the present invention in the next step S _8, the evaporator 12 directly after passing the heater inlet to calculate the air temperature t _1. The heater inlet air temperature t ₁ is obtained by multiplying the temperature difference Δt by the heat transfer coefficient K of the evaporator 12 to obtain a temperature change K · Δt due to the passage of the evaporator 12, and adding the blower suction temperature t to this value. (T ₁ = K · Δt +
t). In summary, heater inlet air temperature t ₁ is as following table.

Then, in step S _9, the vehicle interior outside environmental conditions,
That is, the outside air temperature t detected by the outside air sensor 53
a, room temperature tr detected by room temperature sensor 52, solar radiation sensor 5
4 The amount of solar radiation detected by 4 and the temperature setting section 5 of the operating device 51
Based on the target room temperature set in 1d, the heater outlet air temperature t ₂ (required blowout temperature) as a function value is calculated. Further, in step S _10, it sets the degree of opening of the heater outlet air temperature t ₂ (function values), and the heater inlet air temperature t air mix door 28 on the basis of _1, terminates thereafter. Opening setting of the air mix door 28, as shown in FIG. 4, which is set in advance, based upon the characteristics of the opening degree of the heater outlet air temperature t ₂ and the air mix door 28, the heater outlet air to the characteristics is intended to determine the door opening by matching the temperature t _2, the characteristics are set in accordance with a change in the range of, for example 0 to 20 ° C. heater inlet air temperature t _1.

Therefore, in the present embodiment, the steps in the above flow
The S _1, the mode determination unit 58 for detecting the operating state of the internal / external air switching door 8 is constructed.

Further, step by S ₂ to S _8, the temperature sensor 52 and the temperature tr in the cabin outside respectively detected by the outside air sensor 53, t
and a, the heater inlet air temperature calculating means 59 to calculate the heater inlet air temperature t ₁ based on the determination result by the mode determination unit 58 is configured.

Further, in steps S ₉ and S ₁₀ , the calculation result of the heater inlet air temperature calculating means 59 and the temperatures tr and ta inside and outside the vehicle cabin detected by the room temperature sensor 52 and the outside air sensor 53, respectively.
The control means 57 is configured to control the air mix door 28 based on the target temperature in the vehicle cabin set by the occupant in the temperature setting unit 51d.

Accordingly, in the above embodiment, the control unit 57, room temperature tr, the outside air temperature ta, the amount of solar radiation and the target temperature, i.e. the heater outlet air temperature t ₂ is calculated by the vehicle interior outside of the environmental conditions, this air temperature t ₂ The basic opening of the air mix door 28 in the heater unit 17 is set accordingly.

The heater inlet air temperature t ₁ sucked into the heater unit 17 is calculated by a heater inlet air temperature calculating means 59. That is, in the circulation mode in which inside air is sucked, t ₁ = (k + 1) tr is calculated during cooling, and t ₁ = tr is calculated during non-cooling. In the outside air introduction mode for introducing outside air, t ₁ = (k
+1) ta, and in non-cooling time, t ₁ = ta.

Then, in the control unit 57, this calculated value t ₁ is collated with the characteristics shown in FIG. 4, the basic opening degree of the air mixing door 28 in accordance with the calculated value t ₁ is corrected, the correction opening The operation of the mixed door motor 30 is controlled so that For example, as shown in FIG.
In even t ₂ is constant, as the intake air temperature t ₁ rises from 0 ℃ to 20 ° C., the door opening is smaller corrected.

Accordingly, the occupant of the manual operation, the outside air from the inside air which air is sucked into the air conditioning unit 1, or is switched to the inside air from the outside air, even when the heater inlet air temperature t ₁ is temporarily changed, accordingly Te so that the opening of the air mix door 28 is to compensate for the change in the intake air temperature, that is, when the heater inlet air temperature t ₁ is lowered, the air temperature by increasing the air flow to the heater core 19 by increasing the degree of opening Enhance
When the heater inlet air temperature t ₁ rises on the contrary, it is adjusted so as to lower the air temperature by reducing the air flow to the heater core 19 by the decrease in the opening degree. As a result, irrespective of the switching between the inside air and the outside air of the intake air, the air having a comfortable temperature can always be blown out from the air conditioning unit 1, and the occupant does not feel uncomfortable and the comfort can be improved.

Further, since the opening degree of the air mixing door 28 is controlled based on the inlet air temperature t ₁ of the heater core 19, the opening degree of the air mixing door 28 is controlled based on the air temperature immediately after the suction regardless of the heater inlet air temperature. In this case, it is possible to prevent the temperature of the air taken into the air conditioning unit 1 from changing due to contact with the blower 5 and the passage wall while passing through the air passage. It can be set to an appropriate value, so that air at an appropriate temperature can always be blown from the air conditioning unit 1.

Moreover, the heater inlet air temperature t ₁ is the inside air or external air either is calculated on the basis of the air temperature tr or outside temperature ta among selected by the determination by determining whether it is introduced, the heater unit 17 It is not necessary to install a temperature sensor for directly detecting the air temperature immediately upstream, and the structure can be simplified.

(Effect of the Invention) As described above, according to the present invention, an air conditioner for an auto air conditioner type vehicle air conditioner that controls the opening degree of an air mix door of an air conditioner unit based on environmental conditions including the temperature inside and outside the vehicle compartment is provided. The temperature of the heater inlet air drawn into the heater after passing through the evaporator of the unit is calculated based on the determination result of the inside air or outside air introduction mode, and the calculated value is added to control the opening degree of the air mix door. This eliminates the need for a sensor that directly detects the intake air temperature, compensates for changes in the intake air temperature to the air-conditioning unit, even when the temperature of the intake air changes, while maintaining an appropriate ratio of air passing through the heater. The opening of the air mix door can be adjusted as required. Therefore, air of a comfortable temperature can always be blown out of the air-conditioning unit regardless of switching of the air intake path while simplifying the structure, so that the occupant can feel uncomfortable and the comfort can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of the present invention. 2 and the following drawings show an embodiment of the present invention, FIG. 2 is a schematic sectional view showing the overall configuration of an air conditioner, FIG. 3 is a flowchart showing a control flow, and FIG. It is a characteristic diagram which sets a degree. 1 air conditioning unit, 2 blower unit, 6 outside air inlet, 7 inside air inlet, 8 inside / outside air switching door, 10 cooler unit, 12 evaporator, 17
... heater unit, 19 ... heater core, 28 ... air mixing door, 50 ... control unit, 52 ... inside air sensor, 53 ... ... outside air sensor, 54 ... solar radiation sensor, 57 ... control means, 58 ... mode judging means, 59 ...... heater inlet air temperature calculating means, ta ...... outside air temperature, tr ...... rt, t ₁ ...... heater inlet air temperature, t ₂ ...... heater outlet air temperature.

Claims (1)

(57) [Claims] An inside air intake port for sucking air inside the vehicle into the air conditioning unit; an outside air intake port for sucking air outside the vehicle into the air conditioning unit; Inside / outside air switching means for changing the air suction ratio from each suction port based on the operation of: an evaporator provided downstream of the inside / outside air switching means; and one of intake air passages branched downstream of the evaporator. A heater provided, an air mix door for changing an air inflow rate into an intake air passage provided with the heater, and adjusting an air temperature blown into the vehicle interior; An air conditioner for a vehicle comprising: an environmental state detecting means for detecting an environmental state of the vehicle; and a control means for controlling the air mixing door based on a detection result of the environmental state detecting means. A mode determining means for detecting an operation state of the inside / outside air switching means; and a temperature inside and outside the vehicle compartment detected by the environmental state detecting means;
A heater inlet air temperature calculating means for calculating an inlet air temperature of the heater based on a determination result by the mode determining means, wherein the control means calculates the heater inlet air temperature by the heater inlet air temperature calculating means; An air conditioner for a vehicle, wherein the air mix door is configured to control the air mix door based on a detection result of a detection unit and a target temperature in a vehicle cabin set by an occupant.