Patent GB-474791-A (GB)
Title: Improvements in and relating to the operation of striking and chiming mechanism for clocks
IPC: G04C21/10
Filed: 1936-05-12
Abstract: 474,791. Clocks. HAYCOCK, H., HAYCOCK, F. W., and HAYCOCK, H. May 12, 1936, No. 13395. [Class 139] Striking - mechanism; chiming- mechanism.-In striking or chiming mechanism for clocks, wherein the synchronous-motor driving the 'hands actuates the striking or chiming mechanism under control of cam means actuated by the minute-hand arbor, the cam means effects the rocking of a lever 17, 18, 19 which slidably moves one (13) of two rotatable members 12, 13 to couple it to the other member, one member (13) being a gear-wheel continuously rotated by the motor and the other being a second cam which operates the striking and chiming mechanism. A threearmed lever 17, 18, 19 is counterweighted at 17<1> and pivoted at 16<1> to a block 16 on the rear plate 9. The forked end of arm 19 engages a collar 20 on a freely-mounted wheel 13, continuously driven from the synchronous-motor driving the clock, and holds wheel 13 to the left so that its pin 15 does not engage a pin 14 on a cam 12 which is rigid with shaft 11 and operates the arm 22 on the striking hammer spindle 21. A gathering pallet 23 for the striking rack is also rigid on arbor 11 so that when the end of arm 18 is depressed to rock arm 19 to the right and engage pins 14, 15 a stroke is effected and one tooth of the rack is gathered for each rotation of shaft 11 and wheel 13. On the minute hand arbor is a cam, or a disc with a pin, which at the hour rocks a lever 26, pivoted at 26<1>, to raise an arm 25 about its pivot 25<1>. Pivoted at 27<1> to a depending piece 28 of arm 25 is a lever 27, 29 weighted at 27<a> as arm 25 rises the end 29 moves to the left, Fig. 3, and engages over the end of arm 18. When arm 25 is again lowered, arm 29 depresses arm 18 to engage pins 15, 14 and drive shaft 11. As arm 25 rises, a pin 30 on it lifts a member 24 to release the striking rack. At the end of striking, member 24 falls to a lower position and a pin 31 on it engages lever 27 and removes its arm 29 from the arm 18, whereby the counterweight 17<1> moves arm 19 to the left to disengage pins 15, 14. For chiming, the arrangement of rocking lever, sliding gearwheel &c. is duplicated. Part 47, Fig. 4, corresponds to arm 18, Fig. 1, an inverted T-shaped lever 44 corresponds to arm 27, 29, Fig. 3, and lever 34' corresponds to lever 25. Pins 32, Fig. 4, on the minute wheel 33 raise the lever 34 pivoted at 35 so that the lever 44, pivoted concentrically with pivot 41 on lever 34, rises and falls to the left so that its hook 46 engages over arm 47. When lever 34 clears a pin 32, arm 47 is thus pulled down to engage a chiming coupling similar to pins 14, 15 of Fig. 1. A pin 37 on lever 34 raises a lever 38 pivoted at 39 and a weighted catch 40 is pivoted at 41 to lever 38 so that when the latter is raised, the catch is raised out of one of the slots 42 in the cam wheel 43 and by its weight swings slightly forward against pin 36 to ride on the periphery of the disc 43 and hold the lever 38 up. The cam wheel 43 is driven by the synchronous motor and chiming proceeds until catch 40 falls into the next slot 42. Lever 38 thereby falls, lever 44 is rocked clockwise by pin 45 on lever 38 and hook 46 moves clear of arm 47 so that the chiming coupling is broken.