A solenoid comprising a solenoid coil having a longitudinal hole at the center of a bobbin made of a non-magnetic material and a coil winding wound around the peripheral wall of the bobbin. A yoke comprising a peripheral side plate, an upper end plate and a lower end plate all for the covering the outer...http://www.google.de/patents/US6076550?utm_source=gb-gplus-sharePatent US6076550 - Solenoid and solenoid valve
