GB1273163A - Improvements in or relating to magnetic actuators - Google Patents

Abstract

1,273,163. Selective punching. HONEYWELL Inc. 28 Nov., 1969 [30 Dec., 1968], No. 58348/69. Heading B4B. A mechanical actuator for a selectable punch 7 comprises an interposer flexure member 32 mounted between a pair of guide members 33, 34 and arranged to be reciprocated in order to drive the punch, electromagnetic means 21, 22, 26, 27, 28 being provided for selectively actuating the flexure member for contact with either of the guide members. The guide members and flexure member are secured to a reciprocable member 9 having a slot 42 in which the punch is slidable. The interposer which is of a magnetic material is is normally held against the guide member 33 by means of a permanent magnet 11 having bars 15, 16 fitted with coils 21, 22 respectively; in this position of the interposer the punch moves freely in the slot so that the punch does not pierce the material e.g. a punch card. Upon a voltage being applied to the coils as a result of signal being fed to an amplifier 27 and circuit 26, 28, an electromagnetic force is set up on the coils in opposition to the force of the magnet 11 so that the interposer is held in contact with the guide member 34. The punch is thereby prevented from movement in the slot so that a hole is pierced in the card. Towards the end of the return stroke of the member 9 the circuit provides for the electromagnetic force to be reversed so that interposer is returned to its initial position. At the end of the stroke an electromagnetic force aiding the force of the permanent magnet is terminated so that the interposer is held by the permanent magnet only.