The electromagnetic clutch of the automobile air conditioner is controlled by the air conditioner switch, thermostat, air conditioner amplifier, pressure switch, etc., and turns on or off the power transmission between the engine and the compressor when needed. In addition, when the compressor is overloaded, it can also play a certain protective role.

Among them, the electromagnetic coil is fixed on the casing of the compressor, the drive plate is connected with the main shaft of the compressor, and the pulley is installed on the head cover of the compressor through a bearing, which can rotate freely. When the air conditioner switch is turned on, the current passes through the electromagnetic coil of the electromagnetic clutch, and the electromagnetic coil generates electromagnetic suction, which combines the drive disc of the compressor with the pulley, and transmits the torque of the engine to the compressor main shaft, so that the compressor main shaft rotates. When the air conditioner switch is turned off, the suction force of the electromagnetic coil disappears, the drive disc and the pulley are disengaged under the action of the spring sheet, and the compressor stops working.