GB1460558A - Push button servo control arrangement - Google Patents

Abstract

1460558 Mechanical switches; controlling electric motors INTERNATIONAL STANDARD ELECTRIC CORP 30 April 1975 [7 May 1974] 18047/75 Heading H1N [Also in Division F2] In a servo-system selectively operated by push-buttons 1 Fig. 5 of electric switches 8 for controlling the operation of slides 12 for tape transport mechanisms of cassette tape recorders, the buttons 1 also engage a clutch 5a, Fig. 3, on a driven shaft via a cam portion 1b and pivoted fork 2 whereby the selected cam 5b rotates to operate the selected slider 12. On release of the selected button a holding circuit is maintained to the selected driving motor (9), Fig. 2 (not shown), through a switch 15 operated by a follower 14 initially engaged in a groove of a cylindrical cam 5c and holds the switch 15 closed until the shaft 11 has rotated through one revolution and the follower 14 re-enters the groove. A detent spring 16 also engages in a notch in the cam 5a to assist in retaining the cam in the unoperated position. The clutch is also maintained closed for one revolution by a catch 6a which engages over the end of the clutch fork 2 under spring loading when the clutch initially engages and is withdrawn by a projection 5e on the cam when a revolution is complete. Locking slides not shown hold each slider 12 in its operated position until the next slider is operated.