JPH0635009U - Automotive air conditioner - Google Patents

Abstract

(57) [Summary] [Purpose] To maintain the blast temperature at a constant level, regardless of a sudden change in engine speed. [Structure] The opening of the air mix door 4 is corrected according to a detection signal from an engine speed sensor 13. As a result, the amount of air passing through the heater core 5 is increased or decreased, and the total amount of heat supplied from the heater core 5 to the air passing through the heater core 5 is maintained.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a vehicle air conditioner.

[0002]

[Prior art]

 Conventionally, in an air conditioner for an automobile, an air mix door for adjusting the blast temperature is provided upstream of the heater core. This air mix door divides the air sucked into the unit into air that passes through the heater core and air that does not pass through the heater core according to the opening degree, and adjusts the temperature when the two are mixed. . The opening of the air mix door is controlled so that an appropriate air temperature can be obtained based on the outside air temperature, the inside air temperature, the amount of solar radiation, the engine cooling water temperature, and the set temperature.

[0003]

[Problems to be solved by the device]

 By the way, the flow rate of engine cooling water flowing in the heater core depends on the number of revolutions of the engine. The higher the number of revolutions, the smaller the number of revolutions. Therefore, if the temperature inside the vehicle is controlled only by adjusting the opening degree of the air mix door from the above conditions, for example, when the vehicle is stopped at a red traffic light, the following problems occur.

That is, as shown in the graph of FIG. 5, when the engine speed suddenly decreases at time A, the circulation amount of the engine cooling water decreases accordingly. As a result, the flow rate of engine cooling water flowing in the heater core is reduced, and its heat dissipation capability is reduced, lowering the blast temperature. However, since the amount of air inside the vehicle is larger than that of blown air, even if the blown air temperature drops, as described above, the inside air temperature does not immediately drop, and the change is very gradual. Therefore, the air mix door opening is adjusted for the first time at time B, and even if it is not necessary to lower the internal air temperature, the temperature inside the vehicle is lower than the desired temperature from time A to time B. Air will be supplied. The present invention has been made in view of the above problems, and an object thereof is to provide an air conditioning system for an automobile capable of maintaining a constant blast temperature regardless of a rapid change in engine speed.

[0005]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention provides a heater core provided in one of the air passages by changing the opening of an air mix door that divides the air passage in the unit into two parts. In an air conditioning system for an automobile, which adjusts the temperature of air blown into the vehicle by changing the amount of heated air, the engine speed detecting means and the air mix based on a detection signal from the engine speed detecting means. A control means for correcting the opening degree of the door is provided.

According to the second aspect of the invention, the temperature of the air blown into the vehicle is adjusted by changing the flow rate of the engine cooling water to the heater core that heats the air passing through the unit. The air conditioner is provided with an engine speed detecting means and a control means for correcting the flow rate based on a detection signal from the engine speed detecting means.

[0007]

【Example】

 Next, an embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a schematic view of an air conditioner for a vehicle. Inside a unit 1, a blower 2, an evaporator 3, an air mix door 4 and a heater core 5 are provided respectively. The air sucked into the unit 1 by the blower 2 is cooled and dehumidified by the evaporator 3 and then split by the air mix door 4. Then, one of the split air is left as it is, and the other is heated by the heater core 5 and then mixed again to be blown into the vehicle.

The air mix door 4 is rotated by an actuator 6, and the blowing temperature is adjusted by the opening of the air mix door 4. The actuator 6 is driven based on an operation signal issued from the control device 7. The control device 7 receives detection signals from the inside air sensor 8, the outside air sensor 9, the solar radiation sensor 10, the engine cooling water sensor 11 and the temperature adjustment switch 12 as in the conventional case, and also detects from the engine speed sensor 13. A signal is input.

The control device 7 adjusts the air mix door opening based on the signals from the sensors 8 to 11 and the switch 12, and also based on the detection signal from the engine speed sensor 13, the air mixing door opening degree is adjusted. Correct the mix door opening. Since the adjustment of the opening degree of the air mix door is the same as the conventional one, the correction will be described below with reference to the flowchart shown in FIG.

That is, in step S1, it is determined whether the temperature of the engine cooling water has stabilized. If it is not stable, the air mix door opening is not corrected. This is because even if the opening degree of the air mix door is adjusted according to the engine speed, the blowing temperature changes due to the temperature change of the engine cooling water flowing through the heater core 5, so that the control becomes complicated.

In step S2, it is determined whether the engine speed has changed. If it has not changed, the air mix door opening degree is not corrected as in step S1. In step S3, it is determined whether the engine speed has changed and a certain period of time has elapsed. If it has not elapsed, it is judged that the engine speed change is temporary and the flow rate of the engine cooling water flowing in the heater core 5 does not fluctuate so much, and the air mix door is opened similarly to the steps S1 and S2. The degree is not corrected. In step S4, a correction amount of the air mix door opening is calculated according to the engine speed detected by the engine speed sensor 12, and in step S5, an operation signal is sent to the actuator 6 based on the correction amount in step S4. Correct the air mix door opening.

Specifically, when the engine speed suddenly decreases, as shown in FIG. 3, if the flow rate of the engine cooling water in the heater core 5 sharply decreases at time A, the heat dissipation capability of the heater core 5 decreases. descend. However, due to the operation of the control device 7 described above, the air mix door 4 rotates clockwise around the support shaft 4a in FIG. 1 to correct the opening, so that the amount of air passing through the heater core 5 increases. . As a result, the heat radiating ability of the heater core 5 is reduced, but the amount of air passing through is increased, so that the total amount of heat supplied is equalized, and the conventional reduction in blast temperature is prevented.

Further, even when the engine speed increases, the air mix door 4 rotates counterclockwise around the support shaft 4a in FIG. 1 to reduce the amount of passing air, and to supply the passing air. Since the total amount of heat generated is maintained, an increase in the blast temperature is prevented. In this way, the opening degree of the air mix door is corrected according to the change of the engine speed, that is, the change of the flow rate of the engine cooling water flowing in the heater core 5, and the air is supplied from the heater core 5 to the air passing through the heater core 5. Since the total amount of heat is kept unchanged, the blast temperature is always maintained at the desired value.

It should be noted that, in the above-described embodiment, the one in which the blowing temperature is controlled by correcting the opening degree of the air mix door has been described, but the flow rate of the engine cooling water flowing in the heater core 5 may be adjusted. That is, a valve 5a (shown by a chain double-dashed line in FIG. 1) is provided in the flow path of the engine cooling water, and the valve opening is adjusted according to the change in the engine speed. According to this, the flow rate of the engine cooling water flowing through the heater core 5 is not affected by the change in the engine rotation speed, so that the heater core 5 can always be maintained at a constant heat radiation capacity.

Further, instead of providing the air mix door 4, all the air flowing in the unit 1 may pass through the heater core 5 as shown in FIG. In this case, the temperature of the blown air is adjusted by opening / closing the valve 5a to increase / decrease the flow rate of the engine cooling water passing through the heater core 5. Further, the blast temperature is corrected by providing a cool air passage 14 communicating between the upstream side and the downstream side of the heater core 5 and issuing an operation signal to the actuator 16 for the opening degree of the damper 15 for opening and closing the cool air passage 14. U

[0016]

[Effect of device]

 As is clear from the above description, according to the invention of claim 1, the opening of the air mix door is changed according to the change of the engine speed, so that the engine is changed by the change of the engine speed. Even if the circulating amount of cooling water increases or decreases, the amount of air heated by the heater core changes, the total amount of heat supplied can be maintained constant, and the blast temperature can always be adjusted to the desired value. .

According to the second aspect of the present invention, the flow rate of the engine cooling water to the heater core is adjusted according to the change of the engine speed, so that the heat radiation capacity of the heater core is always constant. It can be maintained, and it is possible to adjust the blast temperature to a desired value.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an automobile air conditioner according to an embodiment.

FIG. 2 is a flowchart showing a control operation in the control device of FIG.

FIG. 3 is a graph showing changes in detected parameters.

FIG. 4 is a partial front view of an automobile air conditioner according to another embodiment.

FIG. 5 is a graph showing changes in each parameter in the conventional example.

[Explanation of symbols]

4 ... Air mix door, 5 ... Heater core, 6 ... Actuator, 7 ... Control device, 13 ... Engine speed sensor.

Claims (2)

[Scope of utility model registration request] 1. An air blower to the inside of the vehicle by changing the opening of an air mix door that divides the air passage in the unit into two, thereby changing the amount of air heated by a heater core provided in one of the air passages. In an air conditioner for an automobile, the temperature of which is adjusted, an engine speed detecting means, and an air mix door opening is adjusted based on a detection signal from the engine speed detecting means to increase or decrease the amount of air passing through a heater core. In addition, the vehicle air conditioner is provided with a control means for keeping the total amount of heat supplied by the heater core constant. 2. An air conditioner for an automobile, wherein the temperature of air blown to the inside of the vehicle is adjusted by changing the flow rate of engine cooling water to a heater core that heats air passing through the unit. And a control means for operating the flow rate adjusting means on the basis of the detection signal from the engine speed detecting means to maintain the flow rate of the engine cooling water flowing in the heater core at a constant value. Air conditioner.