Electrohydraulic control valve is actuated by polarized switching magnet; control electronics reverse polarity of direct current magnet depending on direction of valve change

摘要

The control valve has a 3/2-way valve for connection to a high pressure line and a direct current magnet for connection to an intrinsically safe electrical supply. Control electronics control the 3/2-way valve between closing and opening positions. A permanent magnet holds a switching pin in its switch position and the electronics reverse the polarity of the d.c. magnet depending on valve change. The control valve has a 3/2-way valve for connection to a high pressure line and a direct current magnet for connection to an intrinsically safe electrical supply and driven by control electronics to control the 3/2-way valve between a closing position and an opening position. A permanent magnet (22) holds a switching pin (20) in its switch position and the control electronics reverses the polarity of the d.c. magnet (12) depending on valve change. For changing the valve to the opening position the permanent and d.c. magnets have equal polarity and for closing they have opposite polarity.