| 摘要 |
<p>PURPOSE:To contrive to reduce the current consumption by a method wherein large current is fed in the electromagnetic clutch in order to increase its friction torque when the delivery pressure of a compressor becomes high, while small current is fed when the delivery pressure becomes low. CONSTITUTION:When the delivery pressure of the compressor 3 exceeds a set pressure, a steady-state coil 7 and a starting coil 6 are put into operation in parallel by means of a pressure responding switching circuit 11 so as to feed large current to the electromagnetic clutch, resulting in generating the friction torque necessary for driving the compressor 3 with high driving torque. On the contrary, when the delivery pressure becomes below the set pressure, the starting coil 6 is deengaged and the steady-state coil 7 only is under operation. During the operation of the steady-state coil 7 only, the current past through the electromagnetic clutch is small, resulting in making the power consumption smaller. In such a manner as mentioned above, the power consumption can be reduced during the steady-state operation of the compressor, during which no high driving torque is required.</p> |
