JPH07132726A - Air conditioner for vehicle - Google Patents

Abstract

PURPOSE:To stably perform operating air conditioning without stopping power generating a generator by inhibiting driving an electric motor-driven compressor, when a prescribed condition is not satisfied by a drive signal fluctuated in accordance with generating power in the case of receiving an on-command by an air conditioner. CONSTITUTION:In an air conditioner for a vehicle formed of a refrigerant circuit including an electric motor-driven compressor 2 with a rotational speed adjusted by an inverter 9, an electrically-operated relay Ry serving as a switching means is provided between the inverter 9 and the compressor 2 and controlled by a controller 8. That is, in the case of inputting a drive signal S3 with an on-command of drive on/off command signals P1 relating to the air conditioner, a control signal S4, in which the electrically-operated relay Ry is opened when the drive signal S3 is a prescribed voltage value or less and closed when the prescribed voltage value or more, is output. In this way, before output voltage of a generator 12 arrives at prescribed voltage, operating the compressor 2 is inhibited, to prevent insufficient supply of a field current relating to the generator 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle air conditioner mounted on a vehicle such as an automobile and equipped with an electric compressor.

[0002]

2. Description of the Related Art Conventionally, in a vehicle air conditioner of this type, air is blown onto the surface of an evaporator by a motor fan, and the air loses heat to the refrigerant inside the evaporator to become cold air. , Blow out from the air outlet of the evaporator.

For example, as shown in FIG. 2, in order to keep the temperature of the air blown from the evaporator 4 in the refrigerant circuit 1 constant, a temperature sensor 7 as temperature detecting means is provided near the outlet of the evaporator 4. is there. The temperature detection signal S1 detected by the temperature sensor 7 is input to the controller 8, and the controller 8 outputs a control signal S2 corresponding to the temperature detection signal S1.
Is input to the inverter 9. As a result, the inverter 9
The rotation speed of the electric compressor 2 is adjusted by. Further, the controller 8 controls the start-up or stop of the electric compressor 2 by the inverter 9 according to the drive on / off command signal P1 for the air conditioner.

The refrigerant circuit 1 includes a condenser 3, a receiver dryer 5, and an expansion valve 6, which are connected in series via a pipe. The electric compressor 2 has an electric motor that is a drive unit and a compression operation unit that is a driven unit housed in a casing. Further, in the case of this air conditioner, the three-phase alternating current (generally represented as U phase, V phase, W phase) obtained from the generator 12 by the rotation of the engine 11 was connected to the field coil 13 of the generator 12. The inverter 9 is driven based on the drive signal S3 including the current rectified by the regulator (rectification / stabilization circuit unit) 10.

In this refrigerant circuit 1, an electric compressor 2
Compresses the low-pressure vapor-phase refrigerant flowing from the evaporator 4 and sends it to the condenser 3 as a high-pressure vapor-phase refrigerant. The high-pressure gas-phase refrigerant is radiatively condensed by the condenser 3, becomes a high-pressure gas-liquid mixed-phase refrigerant and flows into the receiver dryer 5, where it is separated into a gas phase and a liquid phase, and only the liquid phase is passed through the expansion valve 6. Inflow. When passing through the expansion valve 6, the refrigerant changes from the high pressure liquid phase to the low pressure gas-liquid mixed phase due to the throttling effect of the expansion valve 6. The low-pressure gas-liquid mixed-phase refrigerant that has passed through the expansion valve 6 flows into the evaporator 4. In the evaporator 4, the low-pressure gas-liquid mixed-phase refrigerant absorbs heat, becomes a low-pressure gas-phase refrigerant, and returns to the electric compressor 2. With the operation of the air conditioner, the refrigerant makes a phase transition while moving in the refrigerant circuit 1 as indicated by an arrow M. Such refrigerant phase transition is repeated during the operation of the air conditioner.

In the case of the refrigerant circuit 1, since the controller 8 constantly controls the rotation speed of the electric compressor 2 in the inverter 9 in accordance with the temperature detection of the temperature sensor 7 described above, the blowout from the evaporator 4 is performed. The temperature of the air is kept constant.

[0007]

In the case of the above-described vehicle air conditioner, the generator 12 is of the self-exciting type having the field coil 13, and the field current is derived from a part of the generated power of the generator 12 itself. The field current is supplied to the field coil 13 by a battery (storage battery) when the engine 11 is started, and the power generation of the generator 12 is performed when the output voltage of the generator 12 reaches a predetermined voltage. A field current is supplied from electric power. Incidentally, the backup power supply technology for supplying the field current by the battery at the time of starting the engine is proposed by the applicant of the present application in Japanese Patent Application No. 4-77570.

However, even when the power source is backed up, when the engine 11 is started with the air conditioner switch in which the electric compressor 2 of the air conditioner works as an electrical load connection state is turned on, the output voltage of the generator 12 is Since the load current is supplied to the electric compressor 2 via the inverter 9 before the voltage reaches the predetermined voltage, the field current is insufficiently supplied and the generator 12 cannot generate power.

FIG. 3 shows the power generation characteristics of the generator 12 under the condition where the rotation speed is constant, by the relationship between the output voltage value V [V] and the load current value I [A]. It can be seen from FIG. 3 that even if the generator 12 is required to supply a load current close to the maximum load current value I _max in the initial low voltage state, it cannot be dealt with. In such a case, sufficient power generation for starting the generator 12 may not be performed, and the electric compressor 2 may not be started.

The present invention has been made to solve the above problems, and a technical problem thereof is to provide an air conditioning system for a vehicle capable of always stably operating the air conditioning.

[0011]

According to the present invention, there is provided a vehicle air conditioner comprising a refrigerant circuit including an electric compressor whose rotation speed is adjusted by an inverter driven by a drive signal which fluctuates in accordance with power generation. Then, in a vehicle air conditioner equipped with a controller that controls the start or stop of the electric compressor by the inverter according to a drive on / off command to the air conditioner, the controller outputs a drive on / off command. When the ON command is received, the vehicle air conditioner including the drive prohibiting unit that prohibits the drive of the electric compressor when the drive signal does not satisfy the predetermined condition is obtained.

According to the present invention, in the above vehicle air conditioner, the drive prohibition means is provided in the controller, or the drive prohibition means is provided between the inverter and the electric compressor. A vehicle air conditioner including a switching means and an opening / closing control means that opens the switching means when the drive signal does not satisfy a predetermined condition and closes the switching means when the drive signal satisfies the predetermined condition. .

On the other hand, according to the present invention, there is provided a vehicle air conditioner comprising a refrigerant circuit including an electric compressor whose rotation speed is adjusted by an inverter, in accordance with a drive on / off command to the air conditioner. In a vehicle air conditioner including a controller that controls the start or stop of the electric compressor by the inverter, when the controller receives an on command of a drive on / off command, an electric compression is performed within a predetermined time. There is provided a vehicle air conditioner including a drive prohibiting unit that prohibits driving of a machine.

In addition, according to the present invention, the vehicle air conditioner further comprises counting means for counting a predetermined time when an ON command is received, and the drive prohibiting means has a predetermined counting result by the counting means. A vehicle air conditioner is obtained in which the driving of the electric compressor is permitted when the time is exceeded and the driving of the electric compressor is prohibited when the result of the counting is within the predetermined time.

[0015]

The air conditioner for a vehicle of the present invention will be described in detail below with reference to the accompanying drawings. Figure 1
1 shows a basic configuration of a vehicle air conditioner according to an embodiment of the present invention. Since this vehicular air conditioner also has basically the same configuration as the vehicular air conditioner shown in FIG. 2, the same components are designated by the same reference numerals and only different parts will be described.

In this vehicle air conditioner, an electric relay Ry as a switching means is provided between the inverter 9 and the electric compressor 2, and the electric relay Ry is connected to the controller 8. The controller 8 is connected between the regulator 10 and the inverter 9 and directly inputs the drive signal S3 from the regulator 10.

Here, the controller 8 drives the on / off command signal P1 for the air conditioner together with the drive signal S3.
When the ON signal of the ON / OFF command signal P1 is received and the drive signal S3 is equal to or lower than the predetermined voltage value, the electric relay Ry is opened, and when the drive signal exceeds the predetermined voltage value. A control signal S4 is output to the electric relay Ry to close the electric relay Ry. That is, the electric relay Ry functions as a switching means, and the controller 8
Serves as an opening / closing control means for controlling opening / closing of the electric relay Ry. As a result, the rotation drive of the electric compressor 2 by the inverter 9 is controlled by the controller 8 by the drive signal S3.
Is less than a predetermined voltage value, the drive signal S is not performed.
It will be performed only when 3 exceeds the predetermined voltage value.

Therefore, the switching function of the electric relay Ry and the opening / closing control function of the controller 8 are combined so that when the controller 8 receives the ON command of the drive ON / OFF commands, the drive signal S3 satisfies the predetermined condition. When the above condition is not satisfied, it works as a drive prohibition means for prohibiting the drive of the electric compressor 2.

According to the vehicle air conditioner of this structure, even if the engine 11 is started with the air conditioner switch in which the electric compressor 2 works as an electric load connection state is turned on, the output voltage of the generator 12 is kept at a predetermined level. Since the load current is not supplied to the electric compressor 2 before reaching the voltage, neither the supply of the field current to the generator 12 becomes insufficient nor the generator 12 stops generating power. The function of the drive prohibiting means described above may be provided in the controller 8 itself without providing the electric relay Ry. In this case, the control signal S2 is transmitted from the controller 8 to the inverter 9,
The operation of starting or stopping the electric compressor 2 may be performed by the inverter 9.

By the way, such a function can be achieved by another simpler structure. Specifically, the drive ON / OFF command P1 is sent to the controller 8.
It is sufficient to provide a drive prohibition means for prohibiting the drive of the electric compressor 2 within a predetermined time when the ON command is received. However, in this case, a timer (not shown) as counting means for starting counting for a predetermined time from when the ON command is further received is provided, and the counting result is predetermined based on the counting result by the drive prohibiting means. When the time is exceeded, the electric compressor 2 is driven, and when the result of counting is within a predetermined time, control is performed to prohibit the rotational driving of the electric compressor 2. Incidentally, the timer may be provided inside the controller 8 or outside the controller 8.

[0021]

As described above, according to the vehicle air conditioner of the present invention, by providing the drive prohibition means, when the on command of the drive on / off commands to the air conditioner is received. In addition, when the drive signal that fluctuates according to the generated power does not satisfy the predetermined condition, the drive of the electric compressor is prohibited, and the drive is performed only when the predetermined condition is satisfied. Even if the engine is started in the ON state of the air conditioner switch that works as a general load connection state, the load current is not supplied to the electric compressor before the output voltage of the generator reaches the predetermined voltage. As a result, the air-conditioning operation can be always performed stably without the supply of the field current being insufficient and the power generation of the generator being stopped.
In addition, other vehicle air conditioners are provided with counting means for counting a predetermined time when an ON command is received, and when the result of counting by the controller indicates that the predetermined time has been exceeded, the electric compressor is rotationally driven to perform counting. When the result shows that the result is within the predetermined time, the electric compressor is not rotationally driven. In this case, the air conditioning operation can be stably performed with a simpler configuration.

[Brief description of drawings]

FIG. 1 shows a basic configuration of a vehicle air conditioner according to an embodiment of the present invention.

FIG. 2 shows a basic configuration of a conventional vehicle air conditioner.

FIG. 3 is a diagram showing the power generation characteristics of a generator provided in the vehicle air conditioner shown in FIG.
This is shown by the relationship of the output voltage value V [V] with respect to [A].

[Explanation of symbols]

 1 Refrigerant Circuit 2 Electric Compressor 4 Evaporator 5 Receiver Dryer 6 Expansion Valve 7 Temperature Sensor 8 Controller 9 Inverter 10 Regulator 11 Engine 12 Generator 13 Field Coil Ry Electric Relay

Claims (5)

[Claims] 1. A vehicle air conditioner comprising a refrigerant circuit including an electric compressor whose rotation speed is adjusted by an inverter driven by a drive signal that fluctuates according to the generated power, and the driving of the air conditioner is turned on. -In a vehicle air conditioner including a controller that controls the start or stop of the electric compressor by the inverter according to an off command,
When the controller receives an ON command of the drive ON / OFF commands, a drive prohibition unit that prohibits driving of the electric compressor when the drive signal does not satisfy a predetermined condition is provided. A vehicle air conditioner. 2. The vehicle air conditioner according to claim 1, wherein the drive prohibiting means is provided in the controller. 3. The vehicle air conditioner according to claim 1, wherein the drive prohibition means does not satisfy the predetermined condition with the switching means provided between the inverter and the electric compressor. An air conditioner for a vehicle, comprising: an opening / closing control means that sometimes opens the switching means while closing the switching means when the drive signal satisfies the predetermined condition. 4. A vehicle air conditioner comprising a refrigerant circuit including an electric compressor whose rotation speed is adjusted by an inverter, wherein the electric type is operated by the inverter in response to a drive on / off command to the air conditioner. In a vehicle air conditioner including a controller for controlling the start or stop of the compressor,
The air conditioner for a vehicle, wherein the controller includes drive prohibiting means for prohibiting driving of the electric compressor within a predetermined time when receiving an ON command of the drive ON / OFF commands. . 5. The vehicle air conditioner according to claim 4, further comprising counting means for counting the predetermined time when the ON command is received, and the drive prohibiting means is provided with a counting result by the counting means. Driving the electric compressor is permitted when the predetermined time is exceeded, and driving the electric compressor is prohibited when the result of the counting is within the predetermined time. apparatus.