JPS6364323B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for a car air conditioner.

FIG. 1 is a circuit diagram showing a conventional car air conditioner control device.

In Fig. 1, 1 is a power supply, 2 is an ignition switch, which is connected via a fuse 3 to one end of a contact 4a of a normally open relay (hereinafter simply referred to as a relay) 4, and the other end is a condenser cooling fan motor. (hereinafter simply referred to as a fan motor) 5 to ground. Note that 4b is a coil for driving the contact 4a. Reference numeral 6 denotes an electronic thermoswitch (hereinafter simply referred to as a thermoswitch), which consists of a normally open contact 6a, a coil 6b, and a switching transistor 6c that turns on at a set temperature, and one end of the normally open contact 6a is connected to the power supply side. , the other end is grounded via a compressor magnetic clutch (hereinafter simply referred to as magnetic clutch) 7.
That is, the magnetic clutch 7 is connected in parallel with the fan motor 5 via the normally open contact 6a of the thermoswitch 6. 8 is an air conditioner switch, and 9 is a blower motor switch (hereinafter referred to as a blower switch). The air conditioner switch 8 and the blower switch 9 are connected in series to the power source 1 via the coil 4b of the relay 4.

Next, the operation will be explained. When the ignition switch 2 is turned on, as well as the air conditioner switch 8 and the blower switch 9, the coil 4b of the relay 4 is energized and the contact 4a is closed, so the fan motor 5 starts rotating by the power supply 1. Here, if the temperature of the evaporator (not shown) is above a specified value, the thermoswitch 6 senses this, the normally open contact 6a turns on, the magnetic clutch 7 is connected, and the air conditioner is operated.

To stop the air conditioner, turn off the air conditioner switch 8 or blower switch 9, the contact 4a of the relay 4 and the normally open contact 6a of the thermo switch 6 will open, the fan motor 5 will stop, and the magnetic clutch 7 will open. If the connection is disconnected, the air conditioner will stop working.

However, in such a conventional car air conditioner control device, the power source of the fan motor 5 and the power source of the thermo switch 6 are connected, so it is difficult to turn off the air conditioner switch 8 or the blower switch 9. When the fan motor 5 is stopped by the fan motor 5, the fan motor 5 rotates due to the inertia of the fan motor 5 and the running wind, so the fan motor 5 becomes a generator and generates starting force, so the thermo switch 6 is activated. As a result, there was a problem that the magnetic clutch 7 was delayed in disengaging or remained connected.

This invention was made by focusing on these conventional problems, and involves connecting a relay that opens and closes a fan motor circuit in parallel with a thermoswitch, and connecting an air conditioner switch and a blower switch in series to that circuit. The aim is to solve the above problems by controlling relays and thermoswitches.

Hereinafter, the present invention will be explained in detail based on the drawings.

FIG. 2 is a circuit diagram showing an embodiment of the present invention. In this embodiment, a series body including a fan motor 5, a magnetic clutch 7, and a thermoswitch 6 as a temperature detector are connected in parallel, and a coil 4b of a relay 4 and a thermoswitch 6 are connected in parallel. A blower switch 9 and an air conditioner switch 8, which operate in conjunction with the blower motor, are connected in series before and after this parallel body, and are further connected to the connecting ends of the fuse 3 and relay 4.

Next, the operation will be explained.

To operate the car air conditioner, turn on the ignition switch 2, turn on the air conditioner switch 8, and the blower switch 9 that is linked to the blower motor.The coil 4b of the relay 4 is energized, its contact 4a is closed, and the fan motor 5 is turned on. rotates. Further, since the thermoswitch 6 is powered on, if the temperature of the evaporator (not shown) is above a specified value, the normally closed contact 6a in the thermoswitch 6 is closed, the magnetic clutch 7 is connected, and the air conditioner is operated.

On the other hand, when stopping the air conditioner, when the air conditioner switch 8 or blower switch 9 is turned off, the contact 4a of the relay 4 and the thermo switch 6 are turned off.
The normally open contact 6a inside is opened, and the fan motor 5 and magnetic clutch 7 are separated. At this time, even if the fan motor 5 rotates due to inertia or the vehicle running wind and generates electricity, the normally open contact 6 in the thermo switch 6
a is open and will not close when the air conditioner switch 8 or blower switch 9 is off, so that delay in disengagement and connection of the magnetic clutch 7 are prevented.

FIG. 3 is a circuit diagram showing another embodiment of the invention. This embodiment is an example in which the fan motor 5, air conditioner switch 8, and magnetic clutch 7 are connected to independent fuses 3 due to fuse capacity and wiring, and the operation is the same as the embodiment shown in FIG. be.

As explained above, in this invention, the coil side of a normally open relay that opens and closes the circuit of a condenser cooling fan motor is connected in parallel with a thermoswitch, and the air conditioner switch and blower switch are connected in series to that circuit. If you turn off the switch or blower switch and stop the car air conditioner, the inertia of the fan motor and the speed of the vehicle will cause the fan motor to rotate and generate electricity, but the magnetic clutch will not be delayed or remain connected. There is no generation of abnormal noise from the magnetic clutch, and the durability is improved.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of a conventional car air conditioner control device, and FIGS. 2 and 3 are circuit diagrams showing embodiments of the present invention. In the figure, 1 is a power supply, 2 is an ignition switch, 4 is a relay, 4a is a contact, 4b is a coil, 5
6 is a fan motor, 6 is a thermo switch, 6a is a normally open contact, 6b is a coil, 6c is a switching transistor, 7 is a magnetic clutch, 8 is an air conditioner switch, and 9 is a blower switch.

Claims (1)

[Claims] 1. A car air conditioner control device in which a compressor magnetic clutch and a condenser cooling fan motor are connected in parallel, and a temperature detector that detects the temperature of the evaporator is used to open and close a circuit of the compressor magnetic clutch. A car air conditioner control device characterized in that the coil side of a normally open relay that opens and closes a circuit of a fan motor is connected in parallel with the temperature detector, and an air conditioner switch and a blower motor switch are connected in series to the parallel circuit.