Patent GB-146245-A (GB)
Title: An improved clock with chimes
IPC: G04B21/02
Filed: 1920-06-28
Abstract: 146,245. Herschede Hall Clock Co., (Assignees of Herschede, W. J., and Cohan, C.). Dec. 14, 1916, [Convention date]. Chimes; striking-mechanism. - In chiming mechanism of the general character disclosed in Specification 14071/08, the chime drum rotates through a number of complete revolutions during every hour and the mechanism for synchronizing the operation of the time indicating means and the chime drum includes a contact member adapted to be disengaged from its track to permit of the shifting of the drum to bring the hour striking means into operation, the hour hand being also capable of independent adjustment. The pindrum 44 makes two revolutions in playing the quarter chimes by means of the pins 45 and hammers 46, and then after being shifted longitudinally makes a third revolution during which it strikes the hour by means of the pins 74 and is shifted a second time; it is then stopped and shortly after is pushed back to be ready for the first quarter of the next hour. Beyond the left end of the drum is a concentric fixed ring 52, Figs. 4 and 5, presenting to the drum a groove 64 of two circles and within this ring is a wheel 53 having a plain crown 62 which makes a step between the ring and the disk of the wheel. The crowned wheel is geared through a countershaft 55 to an equal wheel 57 which is driven from the hour sleeve 13 through equal wheels 14, 59, so that the crown 62 turns within the grooved ring once in twelve hours. The inner end of the groove dips to the crown and the latter has a gap 65 with inclined side 66. The recessed end of the drum contains a radial slide pressed outwards by a spring and from this projects a pin 70 abutting on the grooved ring. The figures show the parts in the positions at the instant when the mechanism is starting to play the fourth quarter and to strike twelve o'clock the pin 70 then being a quadrant forward on the inner circle of the groove. The detent 19 which normally holds the train at the high-speed wheel 25 is supported off its rest 30 by a prop 31 having two notches for engaging a lateral pin 34. Such engagement at the inner notch and the correctly timed release of the train have just been brought about because the hour pin 29 on the central minute-wheel 15 has lifted and let fall a second detent 20 bearing a pin 35. As the fourth quarter is played the pin 70 completes its travel on the inner circle of the groove and arrives at the beginning 79 of the crown 62 whereupon the drum is shifted. As the twelve hours are struck the pin travels round to the gap 65 which lets the drum be shifted the second time. Immediately after, a stud 77 on the drum disengages the detent 19 from the prop and lets it fall to hold the train again. Early in the first quarter of the next hour, the drum is pushed back to the right by the lever 39 and the pin 70 is returned from the position 83 to the outer circle of the groove. At other hours the gap 65 in the crown is less than a circle in advance of the delivery end of the groove so that the pin 70 has a shorter travel on the crown 62 and after the hours have been struck completes the revolution on the disk 63, with the striking pins 74 out of register. At the first, second and third quarters the detent 20 is lifted higher than at the hour the pins 28 being further out than the pin 29. The detent 19 is accordingly propped with its finger 37 in the path of pins 75 and 76 on the drum which act at the end of the first and second quarters respectively; at the end of the third quarter the pin 75 acts again. Motionwork.-The hour wheel 14<a> of the motionwork is loose on the hour sleeve 13 and drives it by friction against a fast wheel 14, thus the hour hand can be adjusted in independence of the minute hand.