GB281350A - Improvements relating to mechanical relay mechanism - Google Patents

Abstract

281,350. Graseby, R. C. June 26. 1926. Clockwork actuation.- Mechanical detent mechanism for clockwork-controlled switches &c. comprises a number of escapement mechanisms cooperating with a stop and being reset directly by a cam, the arrangement being such that after one of the escapements is reset it is held in that position by the cam, whilst after a subsequent operation by another escapement, the former escapement is held reset by a trip lever. As shown, the arm 5 for moving the switch &c. is connected to the clockwork spindle 2 upon which are rigidly secured two cams 8, 9. the cam 9 being provided with a detent 24 and the cam 8 having a projecting tooth 10. Escapement spindles 12, 13 have flats 16, 17 cut in them and are adapted to arrest or release the cam tooth 10 when their corresponding arms 22, 23 lie on the cam surface or fall behind the detent 24. Movement of the arm 22 or 23 behind the detent 24 is, however, presented until one or other of levers 35 is tripped about the pivot 34, the trip levers having pin-and-slot connections 28 - - 31 with further arms 26, 27 carried by the escapement spindles 12, 13. The pin-and-slot connections are such that while, say, in the left-hand connection, the pin 29 abuts the edge of the slot 31, there exists a certain amount of loose play in the other connections. This arrangement permits slight actuation of one trip lever without affecting the escapement mechanism. An interlocking arrangement 41 further prevents both trip levers from being actuated at the same time. The trip levers are restored by light springs 39.