JPS602972Y2 - Drive circuit for air control door for air conditioning - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a drive circuit for an air-conditioning air control door, particularly to a drive circuit that compensates for failures in the motor control circuit.

Generally, a vehicle air conditioner includes a cooler 2 installed in a duct 1 as shown in Fig. 1, a heater 3, and various types of air such as an inside/outside air switching door 4, an air mix door 5, a mode switching door, etc. It has a control door and provides optimal air conditioning.

Recently, it has been proposed that the air control door is driven by a motor 7, and this drive circuit is equipped with a motor forward/reverse circuit and a stop circuit, which are more effective than transistors, etc. It is made up of circuits.

However, this control circuit breaks down due to damage to transistors, etc., resulting in inconveniences such as setting the air mix door 5 to full heater mode even though it is in full cooler mode, making it impossible to perform air conditioning optimally. .

The present invention includes a power source and a motor for driving the air control door, which is connected to both ends of the motor, and supplies current to the motor and controls the direction of the current flowing through the motor to set the position of the air control door. a control circuit to be set; a switch connected in series to the motor and turned off to cut off input to the motor when the air control door is switched to a predetermined position; and one end of the motor connected to the power source; A first manual switch section that switches the other end of the motor between the power source, the other end of the control circuit, and ground; 1. By disconnecting the motor from the control circuit based on the operation of the second manual switch section and allowing current to flow in the forward and reverse directions from the power source to the motor,
This method eliminates the above drawback by making it possible to manually operate the air control door when a failure occurs in the control circuit, and will be described in detail below using examples.

FIG. 2 is a circuit diagram showing an embodiment of the drive circuit for the air control door for air conditioning according to the present invention. The mix door 5 is set in a full cooler mode, that is, so as to cut off cold air from the heater 3, and by reversing the air mix door 5 is set in a full heater mode, that is, in a position that sends cold air to the heater 3 side.

Switches 8 and 9 are connected to one end of this motor 7, switch 8 is provided in the duct 1 so as to turn off when the air mix door 5 is in full cooler mode, and switch 9 is provided in the duct 1 so as to turn off when the air mix door 5 is in full heater mode. It is provided in the duct 1 so as to turn off when the mode is set.

One end of switch 8 is connected to the cathode side of diode 10, one end of switch 9 is connected to the anode side of diode 11, and the anode of diode 10 and diode 1 are connected to each other.
The cathode of No. 1 is connected to the movable contact a of the changeover switch 12, the fixed contact of the changeover switch 12 is connected to the movable contact a of the changeover switch 13, and the fixed contact C is grounded.

A fixed contact C of the changeover switch 13 is connected to a power source, and a fixed contact C is connected to a control circuit 14.

The other end of the motor 7 is connected to a movable contact a of a changeover switch 15, its fixed contact is connected to a movable contact a of a changeover switch 16, and its fixed contact C is grounded.

A fixed contact C of the changeover switch 16 is connected to the power supply, and a fixed contact C is connected to the control circuit 14.

The changeover switches 13 and 15 are interlocked, and the contact C of the switch 13 is normally closed, and the contact C of the switch 15 is normally closed.

Changeover switches 12 and 16 are interlocked, and switch 1
The contact 2 is normally closed, and the contact C of the switch 16 is normally closed.

Note that the changeover switches 12 and 13 constitute a first manual switch section that switches one end of the motor 7 to the power supply, one end of the control circuit 14, and ground, and the changeover switches 15 and 16 configure the other end of the motor 7. A second manual switch section is configured to switch between the power source, the other end of the control circuit 14, and ground.

The control circuit 14 compares the position signal of the air mix door 5 with the setting signal of the air mix door 5, and rotates the motor 6 forward, reverse, and stops so that the difference between the position signal and the setting signal becomes zero.

According to the above configuration, if the control circuit 14 is normal, each changeover switch is in the state shown by the solid line in the figure, and each changeover switch 1
3, 12, 15, and 16 to the motor 7 to control the air mix door 5.

However, if the control circuit 14 fails, proper air conditioning cannot be performed.

Therefore, when the occupant requires the full cooler mode, the changeover switches 13 and 15 are switched.

As a result, current is supplied from the power supply to the earth via the diode 10, switch 8, motor 7, and switch 15 from switches 13 and 12, so the motor 7 rotates forward and the air mix door 5 is set to full cooler mode. .

Here, when the door 5 is set to the full cooler mode, the switch 8 is turned off, so this power supply circuit is cut off and the motor 7 is prevented from locking.

When the occupant requires the full heater mode, the changeover switch 12.16 is switched.

As a result, a current in the opposite direction is supplied to the motor 7, the motor 7 rotates in the reverse direction, and stops when the air mix door 5 enters the full heater mode due to the action of the switch 9.

Therefore, according to the above circuit, even if the control circuit fails, the necessary minimum amount of air conditioning can be performed.

Furthermore, according to this embodiment, the control circuit can be disconnected from the motor drive circuit by switching the changeover switch, so that the air mix door does not malfunction.

In addition, in the present invention, the switches 8 and 9 may be provided between the changeover switch 13, 16 and the power source.

Furthermore, it goes without saying that the present invention can also be applied to the case of driving an inside/outside air switching door or a mode switching door.

[Brief explanation of drawings]

FIG. 1 is a simplified configuration diagram showing an example of a general air conditioner, and FIG. 2 is a circuit diagram showing an embodiment of a drive circuit for an air-conditioning air control door according to the present invention. 1...Duct, 2...Cooler, 3...
... Heater, 7 ... Motor, 8, 9 ...
...Switch, 12, 13, 15, 16...
Changeover switch, 14... Control circuit.

Claims (1)

[Scope of utility model registration request] A power supply and a motor for driving the air control door, connected to both ends of the motor, supplying current to the motor and controlling the direction of the current flowing through the motor to set the position of the air control door at a set position. a control circuit; a switch connected in series to the motor and turned off to cut off input to the motor when the air control door is switched to a predetermined position; and one end of the motor connected to the power supply and the control circuit. a first manual switch section that switches the other end of the motor between the power source, the other end of the control circuit, and ground; . A drive circuit for an air control door for air conditioning, characterized in that the motor is disconnected from the control circuit based on the operation of a second manual switch section, and current is caused to flow in the forward and reverse directions from the power source to the motor.