Patent GB-1062165-A (GB)
Title: Method and apparatus for remote control of pendulum machines of master clocks
IPC: G04R40/00
Filed: 1965-07-07
Abstract: 1,062,165. Radio controlled pendulum clock. LABORATORNI PRISTROJE, NARODNI PODNIK. July 7, 1965 [July 11, 1964], No. 28880/65. Heading G3T. The apparatus controls a pendulum master clock by radio time signals. The pendulum (86), Fig. 2 (not shown) is controlled by adding or removing two ball masses 89, 90 which can be captured by electromagnets 91, 92 or dropped into cups 87, 88 on the pendulum. One minute prior to the signal, e.g. at 11 hours 59 minutes, a synchronous motor is cut-in to rotate gears 2, 6 frictionally coupled to main and auxiliary shafts 3, 7. Simultaneously a solenoid 49 is energized and moves a detent lever 47 to release the auxiliary shaft 7 which carries three cams 31, 32, 33. Six seconds later, the cam 32 closes a contact 43 connecting a first coil 27 of a solenoid 25 with terminals 100, 101. These terminals receive each minute an impulse which is normally transmitted by the master clock to slave clocks and which lasts two seconds. At the same time cam 31 operates a changeover switch 35 to open a control 39 and close a contact 42 for a further six seconds. This disconnects auxiliary coils 57, 58 of two relays 53, 54 from D. C. terminals 96, 97, whereby two switches 59, 60 of relay 53 are opened and two switches 61, 62 of relay 54 which were already open remain so. Magnet 91 is deenergized and the captive ball 89 is released, both balls thus being on the pendulum a nominal fifty-four seconds before the expected time signal. Closing of contact 41 has also energized a solenoid 71 to advance a ratchet wheel 63 one tooth through a pawl 69. This advances a layshaft 64 so that a contact segment 83 meets a brush 84 and a circuit to a second brush 85 is established through a collecting ring 66. At the end of the further six seconds, changeover switch 35 being returned, solenoid 71 is de-energized so that pawl 69 returns to a rest position. Contact 39 renews the connection of coils 57, 58 with the negative D. C. terminal 97 but their relays are not energized as switches 59, 61 are open. The apparatus is now ready for regulation. One of the normal clock impulses at terminals 100, 101 corresponds to the sixtieth minute and goes through contact 43 to energize solenoid 25. This moves a detent lever 24 to start the main shaft 3 which goes until it is arrested by a stop 22 meeting the lever 24 in its new position. Three cams 14, 15, 16 on the main shaft are thus stopped in a position where associated arms of switches 18, 19, 20 touch the cams at 102, 103, 104. The arrangement is such that ten milliseconds after the start the switch 20 is closed and connects the second coil 26 of magnet 25 with the D. C. terminals 96, 97 through the switch 36 so holding the lever 24 before it can be released by cessation of the normal time signal. Two milliseconds thereafter the start switch 18 closes for one hundred and twenty milliseconds, connecting main coil 55 of relay 53 with the radio signal input terminals 98, 99. One hundred and twenty milliseconds thereafter the start switch 19 closes and connects the main coil 56 of the relay 54 with the terminals 98, 99 at the moment when the switch 18 again opens. If the clock is late with respect to the signal magnet 25 is not yet energized to start shaft 3 and switches 18, 19, 20 are open. The circuit between terminal 98 and the main coils 55, 56 is not made. The time signal, which lasts one hundred milliseconds, goes only through a solenoid 79 which lifts a holding pawl 76, and ratchet wheel 63 returns to stop position. Relays 53, 54 remain inactive and both the balls 89, 90 are left on the pendulum to accelerate the clock. If the clock is on time, main shaft 3 starts in coincidence with the signal. Relay 53 is energized transitionally from the signal terminals 98, 99 through switch 18 and coil 55. Switches 59, 60 are closed and relay 53 and magnet 93 energized from the D. C. source. Ball 89 is captured and the clock regulated at correct speed by ball 90 remaining on the pendulum. Simultaneously solenoid 79 is energized by the signal and ratchet wheel 63 returns to stop. If the clock is ahead of the time signal the main shaft 3 starts as before. Transitional switch 18 is unused and on arrival of the signal relay 54 is energized through switch 19, closing switches 61, 62. This maintains relay 54 and both magnets 92, 93 energized, so that both balls are captured and the clock slowed down. Solenoid 78 again returns the ratchet wheel to stop. Forty-eight seconds after the start, i. e. twenty-four seconds after transmission of the sixtieth impulse by the master clock, (a) switch 43 opens and disconnects the first coil 27 of magnet 25 from terminals 100, 101 so that the influence of the following impulses which are transmitted by the master clock each minute is suppressed; and (b) contact 40 is opened and contact 42 closed. The second coil 26 of magnet 25 is thus de-energized. Lever 24 is turned into the track of stop 21 and shaft 3 comes to rest in its initial position. By the closing of contact 42 of changeover switch 36 brush 84 is connected with the positive terminal 96 of the current source. However, owing to return of ratchet wheel 63 to its original position, insulating segment 82 comes under the brush and interrupts the circuit. Thus when the time signal has been correctly received and the clock corrected, the closing of contact 42 has no effect. In case of failure of the time signals, magnet 78 is not energized and pawl 76 prevents return of the ratchet wheel 63. Thus closed contact 42 of changeover switch 36 connects, by way of brush 84, segment 83, ring 65 and brush 85, the auxiliary coil 57 with terminal 96 whilst the coil is connected with terminal 97 through contact 39. Thus relay 53 closes switches 59, 60 and remains energized after contact 42 opens. Magnet 91 attracts ball 89. Thus twenty four seconds after the time for receipt of the absent signal has elapsed, the clock is adjusted by its own action to the correct speed. This is repeated for three regulating periods. In the fourth period a stop 80 and ratchet wheel 63 closes a switch 81 to signal the failure of the time signals.