GB942808A - Improvements in or relating to combined clockwork and manually operated mechanisms - Google Patents

Abstract

942,808. Retractive switches; cam-operated switches. S. SMITH & SONS (ENGLAND) Ltd. May 10, 1961 [May 10, 1960], No. 16545/60. Heading H2B. [Also in Divisions D1 and F2] A combined manual and clockwork actuating mechanism comprising a single manipulating member is so arranged that movement in one direction by hand away from a datum position conditions the clockwork for actuating one control device and movement in another direction by hand away from the datum position actuates another control device. Contacts 15, 16 on blades 13 engage contact strips 14, 17 respectively to provide a double pole two-way switch (only one pole shown). A peg 20 extends through a hole 19 in a base member 10 and acts as a follower for a face cam 41 on the spindle 26 of the manipulating member. The clockwork mechanism embodies a conventional escapement wheel 24 controlled by a balance wheel 25 and driven through a gear train from a spindle 26, to which is attached a mutilated gear-wheel 27. A spindle 29 carrying gear-wheels 28, 31 is swung, in known manner, by a ratcheting action to disengage the gears when the transmission is rotated in one direction. A spiral spring 34 has one end fixed to the spindle 26 and the other end fixed to a lug 35 on an anchor plate 36. An arm 37 is attached to the spindle 26 and engages the lug 35. Rotation of the spindle to wind up the spring 34 moves the arm 37 away from the lug and actuates the ratcheting mechanism. Rotation of the plate 36 is prevented by an abutment 38 engaging in a slot 39 in a plate 23 and a second lug 40 on the plate 36 prevents over-winding of the spring. When the manipulating member is released the spindle 26 rotates, carrying with it the face cam 41 and after a time the pinion 28 enters the cut-away portion of the gear-wheel 27 which then rotates rapidly until the peg 20 reaches the datum position on the cam 41. When the arm 37 engages the lug 35, as the spindle 26 is rotated in the opposite direction to that for winding, the whole anchor plate 36 rotates. A cam plate 46 which is provided with cut-out portions 48, 49, is engaged by a camfollower 50 fixed to a pivoted arm 51 which is tensioned by a spring 53. The cam-plate 46 locates the spindle 26 in the datum position when the follower 50 is in the cut-out portion 48. The cut-out portion 49 detains the spindle in the position where the contacts 16 and the strips 17 are engaged and prevents rotation of the spindle beyond this point.