Electromagnetic solenoid

Abstract

An electromagnetic solenoid for a fluid control valve includes a cylindrical casing accommodating a solenoid coil and having an end wall formed at its one end and which is open at its other end, the open end of the casing being closed by an end cap. A fixed iron core is disposed in and fixedly mounted on the casing. An output rod is disposed in the casing with its one end extending outwardly through the casing end wall for connection with a valve member of the fluid control valve. The output rod slidably extends through the fixed iron core and is supported on its opposite ends by a slide bearing disposed in the end wall of the casing and by a slide ball bearing disposed in the end cap member. A movable iron core is received in the solenoid coil for axial sliding movement and is firmly mounted on the output rod in a face-to-face relation with the fixed iron core at a location such that the distance between the center of the movable iron core and the slide ball bearing is less than the distance between the center of the movable iron core and the slide bearing. The output rod and the slide bearing in the casing end wall are formed of a non-magnetic material. In one embodiment, the end wall of the casing has a fluid passage formed therethrough for providing fluid communication between the interior of the casing and the outside. In another embodiment, the slide bearing in the end wall of the casing has a fluid passage formed therethrough for providing fluid communication between the interior of the casing and the housing bore.