GB817381A - Improvements in or relating to an electromagnet or reciprocating electric motor - Google Patents

Abstract

817,381. Electromagnets; reciprocating motors. POWERS-SAMAS ACCOUNTING MACHINES Ltd. Aug. 7, 1957 [Sept. 26, 1956], No. 29429/56. Class 35. An electromagnet or a reciprocating electric motor comprises an electrically conductive wire 3 applied to the exterior of an electrically insulating tube 2 and in part wound therearound to provide two oppositely wound coils 4, 5 mutually spaced apart axially of the tube, a permanent magnet 1 disposed within the tube and so located relatively to the coils as to be movable axially of the tube when a current is applied to the coils, and restoring means to return the magnet to its starting position when the current ceases. The means may comprise a spring or preferably, as shown, two steel plates 14, 15 whose remote faces 18, 19 are coplanar with respective ends 16, 17 of the magnet. The coils are connected to earth through a brass mounting plate 12 and to either a D.C. or an A.C. supply through a phosphorbronze spring 6, a terminal plug 7 secured to an electrically insulating mounting plate 9 and an input wire 8. Distance pieces not shown interconnect plates 9, 10, 15, 12 to form a unitary structure. A screening ferro-magnetic sleeve 13 having a lengthwise split may be disposed about the tube, and there may be provided a plurality of electromagnets or motors arranged close to one another in rows in which case only those of alternate rows have screening sleeves. The electromagnets may operate a statistical record card punching apparatus through a Bowden wire not shown and a pin 20.