Patent GB-389525-A (GB)
Title: Improvements in or relating to one-revolution and like clutches
IPC: F16D67/02
Filed: 1931-09-18
Abstract: 389,525. Starting and stopping gear ; operating clutches. BRITISH TABULATING MACHINE CO., Ltd., Victoria House, Vernon Place, Southampton Row, London.- (Assignees of Carroll, F. M. ; 1080, Warburton Avenue, Yonkers, and Smith, A. F. ; 4023, Church Avenue, Brooklyn, both in New York, U.S.A.) Sept. 18, 1931, No. 26210. Convention date, Sept. 20, 1930. [Class 80 (ii).] Rotation of a driven element through the whole or part of a revolution is obtained by a main-clutch drive combined with an auxiliary drive or retardation effected during the appropriate part of the motion of a constantly oscillating member so as smoothly and accurately to complete the motion of the driven element after the main clutch is disengaged. The parts are, further, so constructed and arranged as to effect a gradual take-up of the main-clutch drive. The driven member 14, 20 carries a clutch pawl 17, the point 35 of which is adapted to engage with a flattened clutch recess 13 in the driving-member 12 when an arm 36 on the pawl is released by a catch-arm 19 turning with arms 22, 24 on a stationary pin 21. When the pawl 17 is thus released, its arm 36 snaps past a spring catch 37 and rests upon the top surface thereof. The catch-arm 19 is linked to a lever 26 which turns with a lever 30 held in the position shown by a latch 31 until an electromagnet 33 is energized, when a catch 32 is withdrawn from the latch 31 and the lever 30 and the catch-arm 19 move to the left under the influence of a spring 29. The magnet 33 is energized automatically by other machine means at such time that the pawl engages with the bottom of the recess 13 and is move outwards by the surface 38 of the recess so that its arm 36 presses on the upper surface of the catch 37 and levers the driven element 14 forwardly to start its rotation without shock. The pawl ultimately engages a notch 39 at the end of the clutch recess and the clutch drive becomes positive. During its rotation, a cam 23 on the element 14 engages the arm 22 and returns the arm 19 to position to engage the pawl at the end of the revolution. At the same time, the lever 30 is re-engaged with the latch 31 and retained thereby, provided the magnet 33 is not re-energized so that the lever 26 engages the pawl-arm 28 and disengages the clutch. The driven element 14 moves on by its momentum and, in order to ensure that it completes its revolution and engages the arm 36 with the arm 19 without shock, a pin 55 on the element 14 is adapted to be engaged by pawls 49, 58 carried by a rocker 47 which is constantly oscillated around the element 14 by a link 46, lever 45 and levers 42, 43 engaging cams 40, 41 turning with the driving element 12. A lever 53 turning on a fixed pivot 54 has a pin 55 engaging a slot in the lever 30 and has a curved surface x adapted to be engaged by an extension 52 of the pawl 49, when the clutch is in action, so as to prevent engagement of the pawl with the pin 55. When, however, the clutch is disengaged, the lever 53 falls and the pawl 49 moves into the path of the pin 55 which snaps past the pawl 58 to engage between the pawls 58, 49, which are then moving at approximately the same speed as the pin 55 and either drive the element 14 or retard its motion, as required, until the pawl 49 strikes a stop 56 and is disengaged from the pin 55, at which time the arm 36 has been brought to rest against the arm 19. A detent pawl 57 prevents back-running of the element 14.