| 摘要 |
PURPOSE:To provide an overcurrent-preventing function for a driving winding with a simple construction, by a method wherein an electric current supplied to a driving winding for a proportional valve is controlled by an input of a controlling voltage generated by a controlling voltage outputting circuit. CONSTITUTION:An output stage of the controlling voltage outputting circuit 1 is newly provided with an operational amplifier op2 as an output buffer. An output voltage V0' from the amplifier op2 is divided by a potentiometer 5 consisting of resistors R2, R3, and a voltage thus obtained is outputted as a controlling voltage V0. Accordingly, a supply current never exceding the maximum allowable current for the driving winding 3 for the current control type proportional valve being used can be secured, without need to examine the possible voltage range of output voltage signals which may be generated by the circuit 1. |
