| 摘要 |
<p>An electromagnetic shear lock comprising an electromagnet assembly adapted to be mounted to a doorway and an armature assembly adapted to be mounted to a door in a position to be attracted to tile electromagnet, the electromagnet comprises an elongated core of E-shape in cross section with an energizing coil positioned about the middle leg of said E-shaped core and between the outer legs of said E-shaped core. The electromagnet assembly in one embodiment has projections on either side and at both ends thereof extending beyond the surfaces of the core. An armature member has a generally rectangular surface adapted to be mounted to a door and positioned to be attracted by the electromagnet, the armature is relieved at the corners thereof whereby when the armature is attracted to the electromagnet the projections on the extension members extend into the relieved portions of the armature. In an alternate embodiment the armature is recessed at either end thereof intermediate the longitudinal edges and the projections from the electromagnet assembly are received in the recesses. The armature assembly comprises an elongated base member adapted to be secured to a door, the base member receives at least two devices therethrough with the heads of devices extending above the base member. an elongated armature having spaced apart recesses receives and rests on the heads when not attracted to the electromagnet, an elongated leaf spring is secured to the armature intermediate the ends thereof and is secured to the base member adjacent the ends of whereby the spring exerts a return force on the armature when the armature is attracted to said electromagnet.</p> |
