Importance

Loading Importance Indicators...

Abstract

A novel bistable actuator of the coaxial plunger type, requiring only a single electrical coil and a single permanent magnet, provides electrical remote control of extension and retraction of a locking pin in a linear power stroke whose two end conditions require no power and are stabilized by the magnet against environmental acceleration as required for missile or aerospace component locking requirements. The coil is located in a cylindrical soft iron stator shell that acts as a magnetic yoke handling the flux loop from the permanent magnet which, fitted with circular end pole plates, forms a moving armature/plunger driving the locking pin. A specially shaped bobbin carries the coil in the shell/yoke and also forms a tubular guide that confines movement of the armature to axial sliding. The shell/yoke is shaped to form two radial air gaps in the flux loop path of the armature magnet: a working gap traversing a portion of the coil and a return gap outside the coil. Both gaps remain constant over the major extent of the stroke so that the actuator functions in the mode of a speaker voice coil when DC is applied to the coil to move the armature between the stable stroke-ends, the direction being reversible according to the DC polarity. The magnetic holding force at the stroke ends can be independently adjusted in design.

Loading the Abstract Image...

First Claim