Patent GB-1011535-A (GB)
Title: Timepiece movement
IPC: G04C15/00
Filed: 1962-08-13
Abstract: 1,011,535. Clocks. SOC.INDUSTRIELLE DE SONCEBOZ S.A. Aug. 13, 1962 [Aug. 11, 1961], No.30929/62. Heading G3T. A timepiece movement comprises a motion work, a synchronous motor adapted to run at speeds ranging between a minimum and a maximum but having a predetermined average speed, first motion transmitting means including a first face-wheel mechanism connecting the motor to the motion work, a reserve mechanism adapted to run uninterruptedly, and second motion transmitting means including a second face-wheel mechanism connecting the reserve mechanism to the motion work, the reserve mechanism being adjusted to drive the motion work at a predetermined speed between the minimum and average speeds owing to the motor. The time output shaft 15, making a nominal one revolution in twenty-four hours, has a wheel 20 driven by pinion 19 in mesh with wheel 16, free on shaft 15 and driven by pinion 13 fast with ratchet wheel 12 engaged by spring pawl 10 carried from a pinion 7 driven by an output pinion 5 of a step-down gear (not shown) of motor 4. The reserve power spring 23 through barrel wheel 24 drives a wheel 25 geared through pinion and wheel 28, 27 to a pinion 29 fast with a wheel 30 coupled to scape balance 35, 36, 38 having a regulator 41, the wheel 30 bearing a spring pawl 31 engaging a second ratchet wheel 32 fast with pinion 13. Normally the drive from spring 23 through ratchet wheel 32 is overrun at a rate of, say, three to five minutes per day by the motor drive through ratchet wheel 12 and on stopping of the motor the spring takes over. It is shown that allowing for long term frequency variations and interruptions in supply, no significant error in the timing occurs. Spring 23 is kept wound by motor pinion 5 driving a wheel 6 which, through an automatic and intermittent clutching device, Figs. 2, 4, and 5, drives a wheel 47 geared to barrel arbor 42. A crossshaped cam 51 fast with wheel 6 bears on a projection 68 of a locked pivotable member 61 carried by the wheel 47 which overtakes the coaxial wheel 25 in the train from the barrel wheel 24. A stack of independently rotatable discs 48 between the wheels 47, 25 each has a peripheral projection 49 in the path of the next succeeding projection. The lowermost projection 49 is engaged by a nose 69 of a pawl 54 on one side of the wheel 47 which is fast with a second pawl 56 on the other side of this wheel, whilst the uppermost projection 49 is in the path of a stop 50 on wheel 25. Thus when all the projections are abutted and stopped by stop 50, pawls 54, 56 are rocked clockwise to release the pivotable member and move pawl 54 into notch 70 of a latch 59. Cam 51 is released and wheels 47, 6 disengaged. Each cross branch of member 51 successively urges member 61 back to the position where it can be locked by pawl 54 but locking is not effected again until a finger 53a on disc 53 fast with wheel 6 removes latch 59 from the path of pawl 54. Back rotation of the arbor is prevented by a spring 46 on binding post 45 and connected to a pinion 44 meshing with wheel 43. The. balance is regularly given a starting impulse by a resilient tongue 74 on lever 75 which has a sliding pivotal location in a slot 81 and is engaged by a pin 72 on wheel 6.