JP2976892B2 - Air conditioner device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner device mounted on a vehicle such as an automobile, and more particularly, to an air conditioner device having a cooling fan whose rotation speed is variable.

[0002]

2. Description of the Related Art An automotive air conditioner apparatus 10 (hereinafter referred to as an air conditioner) shown in FIG. 3 is provided with a compressor 12, a condenser 13, an expansion valve 14, an evaporator 15 and the like in a refrigerant circulation path 11. The refrigerant circulated by the compressor 12 is condensed in the condenser 13, and the refrigerant is evaporated in the evaporator 15. The compressor 12 is driven by the engine 16 via a pulley, a belt, and the like.

[0003] The evaporator 15 is provided in a cooling unit 20 installed in a vehicle such as a dashboard of a vehicle. The cooling unit 20 supplies air to be cooled to the evaporator 15 by a blower 21 having a variable air volume.
Can be sent to the outlet side of the heater unit 23 via the downstream side 22 of the air blow. An air thermo sensor 24 is provided on the downstream side 22 of the evaporator 15 for blowing air.
The temperature near the evaporator 15 is detected.

On the other hand, a cooling fan 25 is provided facing the condenser 13. The cooling fan 25 has a function of ventilating the condenser 13, and the driving unit 26 can switch the rotation speed between at least two stages (low speed and high speed).

[0005] In the air conditioner device 10 having the above configuration,
When the air conditioner switch 27 is on, if the temperature detected by the air thermo sensor 24 is equal to or higher than a set value (for example, 4 ° C. or higher), the compressor 12 is driven (turned on), and the cooling cycle functions. Further, if the temperature of the evaporator 15 becomes too low, the evaporator 15 becomes frosted. Therefore, as shown in FIG. 4, when the detection value of the air thermo sensor becomes lower than the set temperature (for example, 3 ° C.), the compressor 12 is turned off. Stop (off).

In the air conditioner 10, in addition to the on / off control of the compressor 12, according to the cooling load,
As shown in FIG. 5, it has been proposed to control the rotation speed of the cooling fan 25 as well. That is, when the air conditioner 10 is operated at a time when the cooling load is large, such as in summer,
Since the detection value of the air thermo sensor 24 during the operation of the air conditioner exceeds a set temperature (for example, 8 ° C.), when the set temperature is exceeded, the cooling fan 25 is rotated at a high speed to reduce the amount of air flowing through the condenser 13. Enlarge.
Conversely, when the detected value of the air thermo sensor 24 becomes equal to or lower than the set temperature (for example, 5 ° C.), such as during a period when the cooling load is small, the cooling fan 25 is rotated at a low speed to reduce the amount of air flowing through the condenser 13. Control.

[0007]

However, when the rotation control of the cooling fan 25 is performed based only on the detected value of the air thermo sensor 24 as in the above-mentioned conventional apparatus, there is room for improvement as described below. .

[0008] For example, during a period when the cooling load is relatively small other than in summer, immediately after the engine 16 is started and the air conditioner switch is turned on, the evaporator 15 has not yet exhibited the cooling function. The ambient temperature is almost the same as the vehicle interior temperature. In this case, FIG.
Since the detection value T ₀ of the air thermo sensor 24 exceeds the set value (for example, 8 ° C.), the cooling fan 25 enters a high rotation state despite the small cooling load. When the high-rotation state continues for a while and the evaporator 15 starts to perform the cooling function, the detection value of the air thermo sensor 24 drops below the set value (for example, 5 ° C.), and the cooling fan 25 switches to the low-speed rotation state. .

For this reason, in the above-described conventional example, in the spring or fall seasons when the cooling load is small, the cooling fan 25 excessively rotates at a high speed for a short time immediately after the start of the engine. Gives the occupant the impression that is being wasted.

On the other hand, in a conventional air conditioner, it has been proposed to control the throttle of the engine so as to automatically increase the idling speed of the engine when the air conditioner switch is turned on. There is a problem that the idling rotational speed becomes too high at a time when the engine speed is small, which adversely affects noise, fuel consumption, and the like.

Accordingly, an object of the present invention is to provide an air conditioner apparatus which can prevent the cooling fan from rotating at an excessively high speed or idling too high when the cooling load is small.

[0012]

According to one aspect of the present invention, there is provided an air conditioner apparatus comprising: a cooling fan for ventilating a condenser for condensing refrigerant circulated by a compressor; A temperature detecting means disposed on the downstream side of the evaporator provided in the circulation path of the evaporator, and a high-speed rotation of the cooling fan when a detection value during operation of the air conditioner detected by the temperature detecting means is equal to or higher than a set value. Control means for causing the cooling fan to rotate at a low speed when the detected value does not reach the set value, the control means comprising: an engine for driving the compressor is started and an air conditioner switch is turned on. Until a predetermined time elapses after is turned on, regardless of the detection value from the temperature detection means Characterized in that continuing the cooling fan rotating at low speed.

In the air conditioner of the first aspect, the cooling fan is controlled to rotate at a low speed until a predetermined time (for example, 12 seconds) elapses after the engine is started. High rotation for a short time is avoided. When the cooling load is large, after the predetermined time has elapsed, the cooling fan is switched to high rotation according to the value detected by the temperature detecting means, so that the amount of air flowing through the condenser can be increased.

An air conditioner apparatus according to a second aspect of the present invention includes the cooling fan and the temperature detecting means, and the first detection during operation of the air conditioner detected by the temperature detecting means. Control means for causing the cooling fan to rotate at a high speed when the value is equal to or more than a first set value (for example, 8 ° C. or more) and for causing the cooling fan to rotate at a low speed when the first detected value does not reach the first set value. The control means inputs a second detection value detected by the temperature detection means immediately after the start of the engine that drives the compressor or immediately after the air conditioner switch is turned on; When the second detection value is equal to or more than a second set value (for example, 30 ° C. or more) that is a set value larger than the first set value, the idle of the engine is set. And maintains the idling at a low rotation state when maintaining the grayed to high revolution state and the second detection value does not reach the second predetermined value.

In the air conditioner of the second aspect,
The idling speed is controlled in accordance with the evaporator downstream temperature (second detection value) immediately after the engine is started or immediately after the air conditioner switch is turned on. For example, when the cooling load is large, such as in summer, immediately after the engine is started and the air conditioner switch is turned on, the evaporator has not yet performed the cooling function, and therefore, the ambient temperature of the air thermo sensor is not equal to the vehicle interior temperature. Almost the same is quite high. In this case, if the second detection value exceeds the second set value (for example, 30 ° C.), the engine control is performed so as to increase the idling rotational speed, so that the compressor rotational speed increases. The second detection value is a second set value (for example, 30
° C), it is determined that the cooling load is small, and the idling speed is low.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention described below is similar to the above-described air conditioner 10 (FIG. 3).
A compressor 12 and a condenser 1
3, an expansion valve 14, an evaporator 15, and the like. The refrigerant circulated by the compressor 12 is condensed by the condenser 13 and the evaporator 15
At which the refrigerant evaporates. Arrow A in the figure indicates the direction in which the refrigerant flows.

The evaporator 15 is provided on a cooling unit 20 mounted in the vehicle such as a dashboard of the vehicle. The cooling unit 20 supplies air to be cooled to the evaporator 15 by a blower 21 having a variable air volume.
Can be sent to the outlet side of the heater unit 23 via the downstream side 22 of the air blow. An air thermosensor 24 functioning as a temperature detecting means is provided on the downstream side 22 of the evaporator 15 to detect the temperature near the evaporator 15.

On the other hand, a cooling fan 25 is provided facing the condenser 13. The cooling fan 25 has a function of ventilating the condenser 13, and the driving unit 26 can switch the rotation speed between at least two stages (low speed and high speed).

As will be described below, the air conditioner 10 has a control means 30 using a microcomputer or the like.
Is controlled by FIG. 1 is a flowchart showing the outline of the processing contents of the control means 30. In an engine start step S1 in FIG. 1, an ignition key is turned on to start the engine, and when the engine is started by performing cranking, the start confirmation signal is controlled by the engine speed exceeding a set value. Means 30 are provided. Here, whether the engine has started or not is determined
For example, the number of crankshaft rotations per unit time is counted by a crank angle sensor installed on the crankshaft, and when the number of rotations exceeds a set value, the engine control computer of the control means 30 detects the start of the engine. .

Then, it is determined whether or not the air conditioner switch 27 is turned on. If the air conditioner switch 27 is turned on, it is determined in step S2 whether a predetermined time (for example, 12 seconds) has elapsed since the start of the engine. It is determined whether or not. When it is within a predetermined time (12 seconds) from the start of the engine, the cooling fan 25 is kept rotating at a low speed regardless of the detection value of the air thermo sensor 24. In addition,
Within several seconds to 10 seconds after the air conditioner switch is turned on, the temperature of the evaporator 15 is sufficiently reduced, and the cooling cycle starts to function.

After a lapse of a predetermined time (12 seconds) from the start of the engine, it is determined in step S3 whether or not the detection value of the air thermo sensor 24 has become equal to or higher than a set temperature (for example, 8 ° C.). At this time, since the cooling cycle is already sufficiently functioning, the detection value of the air thermo sensor 24 near the evaporator 15 is sufficiently lower than the temperature inside the vehicle. If the detected value of the air thermosensor 24 is equal to or higher than the set temperature (for example, 8 ° C.) in step S3, it is necessary to increase the cooling capacity.
By setting the idling at a high rotation state, the rotation speed of the compressor 12 is increased.

If the detected value is less than 8 ° C. in step S3, the cooling fan 25 is rotated at a low speed,
Set idling to low speed. Step S4
It is determined whether or not the detection value of the air thermo sensor 24 has become equal to or lower than a set temperature (for example, 5 ° C.). If the temperature has become equal to or lower than the set temperature (5 ° C.), the cooling fan 25 is rotated at a low speed and idling is reduced at a low speed. State.

According to the air conditioner apparatus 10 having the above-described structure, the cooling fan 25 is controlled to rotate at a low speed until a predetermined time (for example, 12 seconds) elapses after the engine is started. Sometimes, the high speed rotation of the cooling fan 25 for a short time is avoided.
When the cooling load is large, the cooling fan 25 is switched to high rotation according to the detection value of the air thermo sensor 24 after the predetermined time (12 seconds) elapses.
Can increase the amount of ventilation.

The controller 30 stops the compressor 12 when the detected value of the air thermo sensor 24 falls below, for example, 3 ° C. in order to prevent frost on the evaporator 15 as in the prior art. (For example, the compressor 12 is driven when the temperature becomes 4 ° C. or more) (FIG. 4).

Next, a second embodiment of the present invention will be described. The basic configuration of this embodiment is the same as that shown in FIG. FIG. 2 is a flowchart showing the processing contents of the control means 30 of the second embodiment. In an engine start step S10, a start confirmation signal is given to the control means 30 when the engine is started in the same manner as in the first embodiment. Can be Further, in step S11, the evaporator downstream temperature T1 immediately after the start is detected by the air thermosensor 24, and if it is equal to or higher than the second set temperature (for example, 30 ° C.), a pulse is issued.

Then, it is determined whether or not the air conditioner switch 27 is turned on. If the air conditioner switch 27 is turned on, the evaporator downstream temperature T1 immediately after starting is set to the first set temperature (for example, 8) in step S12. ° C), which is a second set temperature (30
° C) or more, it is determined whether or not the second set temperature (30
° C) or more, it is determined that the cooling load is large, and the idling of the engine is set to a high rotation state. If the temperature T1 is lower than the set temperature (30 DEG C.), it is determined that the cooling load is small, and idling is set to a low rotation state.

Thereafter, in step S13, the detection value of the air thermo sensor 24 is changed to the first set temperature (for example, 8 ° C.).
Is determined. At this time, since the cooling cycle is already sufficiently functioning, the detection value of the air thermo sensor 24 near the evaporator 15 is sufficiently lower than the temperature inside the vehicle. Here, if the detection value of the air thermo sensor 24 is equal to or higher than the first set temperature (8 ° C.), it is necessary to further increase the cooling capacity. Therefore, the cooling fan 25 is rotated at a high speed to increase the amount of air flow to the condenser 13. . If the detected value is lower than the first set temperature (8 ° C.), the cooling fan 25 is rotated at a low speed. In step S14, the detection value of the air thermo sensor 24 is set to the set temperature (for example, 5
(° C.) or less, and when the temperature falls below the set temperature (5 ° C.), the cooling fan 25 is rotated at a low speed.

In the above description, the detected value T1 of the air thermo sensor 24 immediately after the start of the engine is input to the control means 30 in step S11. The detection value T1 of the thermo sensor 24 may be input to the control means 30.

According to the air conditioner device 10 of the second embodiment, idling can be prevented from becoming unnecessarily high during a period in which the cooling load is relatively small other than, for example, in summer. That is, the parked engine 16
Immediately after turning on the air conditioner switch 27, the temperature of the evaporator 15 is almost the same as the cabin temperature, and the detected value of the air thermo sensor 24 at this time (second
If the detected value exceeds the second set value (for example, 30 ° C.), it can be determined that the cooling load is large. Then, only in that case, the engine control is performed to increase the idling rotational speed and otherwise reduce the idling rotational speed.For example, in a period when the cooling load is relatively small other than in summer, idling is performed at a higher rotational speed than necessary. Can be avoided.

[0030]

According to the present invention, the noise can be suppressed by preventing the cooling fan from rotating excessively high for a short time at the time of starting the engine when the cooling load is small. It is possible to prevent the number of idling revolutions from becoming too high, thereby improving fuel efficiency.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a flow of control of an air conditioner according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a control flow according to another embodiment of the present invention.

FIG. 3 is a schematic diagram illustrating a configuration of an air conditioner device.

FIG. 4 is a diagram showing on / off control temperatures of a compressor.

FIG. 5 is a diagram showing an on / off control temperature of a cooling fan.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Air conditioner apparatus 12 ... Compressor 13 ... Condenser 15 ... Evaporator 16 ... Engine 24 ... Air thermo sensor (temperature detection means) 25 ... Cooling fan 30 ... Control means

Claims (2)

(57) [Claims] 1. A cooling fan for ventilating a condenser for condensing a refrigerant circulated by a compressor, a temperature detecting unit disposed downstream of an evaporator provided in a refrigerant circulation path, and a temperature detecting unit. Control means for causing the cooling fan to rotate at a high speed when the detected value during operation of the air conditioner detected by the air conditioner is equal to or greater than a set value, and for causing the cooling fan to rotate at a low speed when the detected value does not reach the set value. In the air conditioner device, the control unit may perform the cooling operation regardless of a detection value from the temperature detection unit until a predetermined time elapses after an engine that drives the compressor starts and an air conditioner switch is turned on. An air conditioner characterized by keeping the fan rotating at low speed. 2. A cooling fan for ventilating a condenser for condensing a refrigerant circulated by a compressor, temperature detecting means disposed downstream of an evaporator provided in a refrigerant circulation path, and temperature detecting means. When the first detection value detected during the operation of the air conditioner is equal to or more than the first set value, the cooling fan is rotated at a high speed, and when the first detection value does not reach the first set value, the cooling fan is activated. An air conditioner device having a control means for rotating the compressor at a low speed, wherein the control means detects the temperature by the temperature detecting means immediately after the engine for driving the compressor is started or immediately after the air conditioner switch is turned on. When a detected value is input and the second detected value is equal to or greater than a second set value which is a set value larger than the first set value The air conditioner apparatus according to claim 1, wherein idling of the engine is maintained at a high rotation state, and idling is maintained at a low rotation state when the second detection value does not reach the second set value.