JP2880512B2 - Control unit for vehicle air conditioning - Google Patents

Description

The present invention relates to a vehicle air conditioning control device.

(Prior Art) Conventionally, a compressor driven by an engine, an evaporator which forms a refrigeration cycle together with the compressor and is disposed in a ventilation passage of an air conditioner, and a cooling water for an engine which is also disposed in the ventilation passage 2. Description of the Related Art An air conditioner for a vehicle including a heater core for circulating air is known.

In such an air conditioner, it is desirable to dehumidify the air in order to pursue comfort, but when the outside air temperature is sufficiently low, the moisture contained in the air is small, and it is necessary to operate the compressor to perform dehumidification. No, for example,
As described in -14014, the outside air temperature is detected, and the ON / O of the compressor is determined according to the detected value of the outside air temperature.
Performing FF control is known.

(Problems to be Solved by the Invention) However, when the compressor ON / OFF is controlled based only on the outside air temperature in the middle period such as spring and autumn, if the outside air temperature is slightly low, for example, about 10 ° C. If there is, after operating the compressor and cooling the air by the evaporator, it will be heated by the heater core to a predetermined temperature, but if the temperature of the engine cooling water is low, the air will not be sufficiently raised by the heater core, There is a problem that cold air at a temperature lower than a desired temperature blows out at the time of startup.

The present invention has been made in view of such a point, and an object of the present invention is to provide a vehicle air-conditioning control device that can prevent the blowing of cool air at the time of startup in an intermediate period such as spring or autumn.

(Means for Solving the Problems) In order to achieve the above object, a solution of the present invention according to claim 1 is to provide a compressor driven by an engine and a refrigeration cycle together with the compressor so as to form a refrigeration cycle in an air passage of an air conditioner. And an outside air temperature detecting means for detecting the outside air temperature, and an outlet for calculating an outlet temperature downstream of the heater core. Receiving the outputs of the temperature calculating means, the outside air temperature detecting means and the outlet temperature calculating means, and setting the compressor only when the detected value of the outside air temperature detecting means is equal to or more than a predetermined value and the detected value of the blowing temperature calculating means is equal to or more than a predetermined value. And a control means for driving the.

According to a second aspect of the present invention, a water temperature detecting means for detecting a temperature of cooling water circulating in a heater core is used in place of the blow-out temperature calculating means, and the outputs of the outside air temperature detecting means and the water temperature detecting means are received. Control means for driving the compressor is provided only when the detected value of the outside air temperature detecting means is equal to or more than a predetermined value and the detected value of the water temperature means is equal to or more than a predetermined value.

Furthermore, a solution of the invention according to claim 3 is a compressor driven by an engine, an evaporator which forms a refrigeration cycle together with the compressor and is disposed in a ventilation passage of an air conditioner, and also disposed in the ventilation passage. A heater core for circulating cooling water for the engine, an outside air temperature detecting means for detecting an outside air temperature, a water temperature detecting means for detecting a temperature of cooling water circulating through the heater core, the outside air temperature detecting means and a water temperature detecting means Output temperature calculating means for calculating the blow-off temperature on the downstream side of the heater core, and prohibiting receiving the output of the blow-off temperature calculating means to prohibit the blowing of the conditioned air when the blow-off temperature on the downstream side of the heater core is lower than a predetermined value. Means shall be provided.

(Operation) According to the invention of claim 1, the compressor is driven only when the outside air temperature and the blow-out temperature on the downstream side of the heater core are both equal to or higher than the predetermined value, and unexpected cold air is not blown out.

According to the second aspect of the present invention, the compressor is driven only when both the outside air temperature and the temperature of the cooling water circulating in the engine are equal to or higher than a predetermined value, and unexpected cold air is not blown out.

Furthermore, according to the third aspect of the invention, when the blowout temperature on the downstream side of the heater core calculated from the outside air temperature and the engine coolant temperature is equal to or lower than a predetermined value, blowout of the conditioned air is prohibited. Not done.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

In FIG. 1 showing the overall configuration of an air conditioner for a car,
Reference numeral 1 denotes a blower unit, which controls the inside and outside air switching door 4 to control the inside and outside air, and an inside air intake hole 2 formed in a floor panel (not shown) and a first outside air intake hole opened below the floor panel. 3 is selectively performed. The blower unit 1 has a blower 5 arranged in an air passage, and a cooler unit 6 and a heater unit 7 are connected downstream.

The cooler unit 6 has an evaporator 8, which forms a refrigeration cycle together with a compressor 21 described later.

The heater unit 7 is configured to circulate cooling water of the engine, has an air mix door 9 and a heater core 10 arranged in an air passage, and controls an opening degree of the air mix door 9. This adjusts the temperature of the blown air.

11 is a vent outlet, 12 is a differential outlet, and 13 is a heat outlet, which are vent door 14, differential door 15, and heat door 16, respectively.
The amount of air blown is controlled by driving and controlling the opening degree of the actuator by the actuator 17.

Reference numeral 20 denotes an engine, and the compressor 21 is driven by the engine 20. That is, the compressor
The drive shaft of 21 is connected to a pulley 23 via an electromagnetic clutch 22, and the pulley 23 is linked via a belt 25 to another pulley 24 fixed to the crankshaft of the engine 20.

Reference numeral 31 denotes a controller, as shown in FIG. 2, an outlet temperature detecting means 101 for detecting an outlet temperature on the downstream side of the heater core 10, an outside air temperature sensor 32 as an outside air temperature detecting means for detecting an outside air temperature, and Control means 102 for receiving the output of the blow-out temperature detecting means and driving the compressor 21 only when the detected value of the outside air temperature sensor 32 is equal to or more than a predetermined value and the detected value of the blow-out temperature detecting means 101 is equal to or more than a predetermined value. .

In FIG. 1, reference numerals 41 and 42 denote air volume setting devices and temperature setting devices provided on the instrument panel 43, 44 denotes a radiator, 45 denotes a condenser, 46 denotes a duct sensor, and 47 denotes the temperature of the inlet portion of the heater core 10. Air temperature sensor for detecting, 48 is a water temperature sensor for detecting the temperature of engine cooling water, 49
Is the solar radiation sensor, 50 is the air mix door and heater core 10
An actuator that controls the opening of the control door 51 that controls the amount of blown air, and has a potentiometer 50a.

Next, the flow of control of the compressor 21 by the controller 31 will be described, but before that, the basic control of air conditioning will be described. .

As shown in FIG. 3, when the ignition is turned on (step S0), the CPU is reset (step S1), and it is determined whether or not the CPU goes out of control (step S2). On the other hand (Step S
3) If runaway, return to step S1.

Next, if there is an abnormality in the check mode, a failure diagnosis is performed (step S10), and then the process returns to step S2.
The total signal T is calculated on the basis of the signal (step S4).

T = (tr−25) + α (ta−25) + β (td−12) −γ (Td
−25) tr: Indoor sensor temperature ta: Outside air sensor temperature td: Duct sensor temperature Td: Temperature set value α, β, γ: Correction count The control of the air mix door 9 based on the comprehensive signal T is shown in FIG. 5 (step S5), air volume control is performed according to FIG. 5 (step S6), compressor control is performed (step S7), and blowout mode control is performed to maintain the cabin in a state of head and foot heat (step S8), Furthermore, inside / outside air introduction control is performed to switch the inside / outside air in order to reduce not only the cooling load but also the fogging of the windows as well as the ventilation (step S).
9), and then return to step S2. 4 and 5
In the figure, the numbers in parentheses indicate the outside temperature of 25 ° C and the temperature setting of 25.
Shows the room temperature equivalent [° C] when the temperature is 12 ° C and the duct sensor is 12 ° C.

The compressor in step S7
As shown in FIG. 6, when the control of 21 is started, first, it is determined whether or not the outside air temperature is higher than a predetermined value by a signal from the outside air temperature sensor 32 (step S11), and If it is higher than the predetermined value, the inlet air temperature tm of the heater core 10 is detected by the signal from the air temperature sensor 47 (step S12), and the engine cooling water temperature tw is detected by the signal from the water temperature sensor 48 (step S12). S13), Step S described above
Based on the control of 6, the air volume Va of the blower 5 is detected (step S14), the opening degree θ of the air mix door 9 is detected (step S15), and the blowout temperature ta of the heater core 8 is calculated (step S16). . That is, ta = f (tm, tw, Va, θ) After that, it is determined whether or not the blow-out temperature calculated in step S16 is higher than a predetermined value (step S17). Since there is no possibility that cold air will blow out, the electromagnetic clutch 22 is connected and the compressor 21 is turned on (step S18). On the other hand, if the blow-out temperature is low, cool air may blow out from the blow-out port. Disconnect and turn off compressor 21 (step S1
9).

Also, in the determination in step S11, even when the outside air temperature is lower than the predetermined value, the compressor 21 is turned off without calculating the blowout temperature of the heater core 10 because there is a possibility that cool air may blow out from each blowout port (step S19). ).

In the above embodiment, the blowout temperature of the heater core 10 is directly calculated, but since the blowout temperature substantially corresponds to the cooling water temperature of the engine, instead of the blowout temperature,
The engine cooling water temperature detected by the water temperature sensor 48 may be used.

That is, as shown in FIG. 7, when started, it is determined whether or not the outside air temperature is higher than a predetermined value (step S2).
1) If the blow-out temperature is high, it is subsequently determined whether or not the engine coolant temperature is higher than a predetermined value based on a signal from a coolant temperature sensor 48 that detects the engine coolant temperature (step).
S22) When the cooling water temperature is high, there is no possibility of blowing out cool air, so the compressor 21 is turned on (step S23). On the other hand, when the cooling water temperature is low, cool air may blow out, so the compressor 21 is turned off (step S23). S24).

Further, even when the outside air temperature is lower than the predetermined value in the determination in step S21, the compressor 21 is turned off because there is a possibility that cold air may be generated (step S24).

According to the first aspect of the present invention, the compressor is driven only when the outside air temperature and the blow-out temperature downstream of the heater core are both equal to or higher than a predetermined value. It is possible to prevent cold air from blowing out carelessly at the time of startup.

According to the second aspect of the invention, the compressor is driven only when both the outside air temperature and the engine cooling water temperature are equal to or higher than a predetermined value. Therefore, substantially the same effect as the first aspect of the invention can be obtained.

Further, according to the third aspect of the present invention, the blowing of the conditioned air is prohibited when the blowing temperature downstream of the heater core calculated from the outside air temperature and the engine cooling water temperature is equal to or lower than a predetermined value. It is possible to prevent the blowing of cold air.

[Brief description of the drawings]

1 shows an embodiment of the present invention, FIG. 1 is an overall configuration diagram of an air conditioner of an automobile, FIG. 2 is a block diagram showing a configuration of a controller, FIG. 3 is a flowchart of basic control of the air conditioner, FIG. 4 and 5 are diagrams showing the basics of the air mix door control and the air volume control, respectively, and FIGS. 6 and 7 are flow charts showing the processing flow of the controller. DESCRIPTION OF SYMBOLS 1 ... Blower unit, 8 ... Evaporator, 7 ... Heater unit, 10 ... Heater core, 21 ... Compressor, 31 ... Controller, 32 ... Outside air temperature sensor, 42 ... Water temperature sensor, 101 ...
Blow-out temperature detection means, 102 ... control means.

Claims (2)

(57) [Claims] 1. A compressor driven by an engine, an evaporator which forms a refrigeration cycle together with the compressor and is disposed in a ventilation passage of an air conditioner, and a cooling water of the engine which is also disposed in the ventilation passage. A heater core for detecting an outside air temperature, an outlet temperature calculating unit for calculating an outlet temperature on the downstream side of the heater core, and receiving outputs of the outer air temperature detecting unit and the outlet temperature calculating unit. A control device for vehicle air conditioning, further comprising control means for driving the compressor only when the detected value of the outside air temperature detecting means is equal to or more than a predetermined value and the detected value of the blow-out temperature calculating means is equal to or more than a predetermined value. 2. A compressor driven by an engine, an evaporator which forms a refrigeration cycle together with the compressor and is disposed in a ventilation passage of an air conditioner, and a cooling water for the engine which is also disposed in the ventilation passage. A heater core, an outside air temperature detecting unit for detecting an outside air temperature, a water temperature detecting unit for detecting a temperature of cooling water circulating through the heater core, and receiving outputs of the outside air temperature detecting unit and a water temperature detecting unit. A control device for vehicle air conditioning, further comprising control means for driving the compressor only when a detected value of an outside air temperature detecting means is equal to or more than a predetermined value and a detected value of the water temperature means is equal to or more than a predetermined value.