Patent GB-794563-A (GB)
Title: Improvements in or relating to automatic apparatus for receiving or despatching signals
IPC: H04L15/26
Filed: 1954-03-09
Abstract: 794,563. Alarm signals. DAVALL & SONS, Ltd., S., and KRIVOCHEEF, G. June 9, 1955 [March 9, 1954], No. 6878/64. Class 118 (1). In automatic apparatus for sending signals, for example S.O.S. wireless signals, automatically and repeatedly a clockwork transmitter is provided which has a going train regulated by an escapement determining the initiation of signals, and a separately regulated functional train for operating the signals, and means to set the functional train in operation by the going train when the transmission or reception of signals is to be started. The going train comprises a spring-driven arbor 13, Fig. 2, driving gears 16-21 regulated by an escapement 22. On a spindle 23 of this going train which rotates once per hour is a release cam 24 having five notches 25 co-operating with a cam release lever 26. The spring barrel 14 carries a gear 27 which drives at least one functional train 30-33 regulated by an escapement 34. The lever 26 releases the functional train every twelve minutes which after its signal cycle stops and re-sets the lever 26. One or more cams 36, 37 are mounted on a spindle 35 of the functional train and rotate once for each signal cycle, which single rotation takes much less than twelve minutes. The release lever 26, Fig. 1, carries a pin 28 which may drop into one of the notches 25, and it has an arm 29 which urges the pin 28 into the notches and carries a pin 40 working in a slot in a bell crank 41 so that when the pin 28 is raised out of a notch 25 the functional train escapement wheel 44 is stopped by a wire 42 and signals cease. The lever 41 is pivoted on an arbor 43 which may slide laterally but is spring urged to bear on a face of the cam 37. The cam 37 has a sloping portion 45 and at the end of a cycle the arbor 43 drops on to the slope 45 and brings the brush 42 against the balance wheel 44. When however the lever 26 operates and rotates the lever 41 to start the functional train, the slope 45 presses the arbor 43 endwise and removes the brush from the plane of the balance wheel 44 before the pin 28 lifts out of the notch 25, and holds the brush out of the way until the cam 37 has completed its cycle. Cam 36 has an edge which sends a distress signal and ship data automatically by operating a switch 50, Fig. 3, after which signal the cam 37 and switch 50 cut out the battery. The cam and switch therefore switch the battery in again when movement recommences, and allow time for valves to warm up before the cam sends an S.O.S. This economizes battery and spring power as the spring in the case 14 has for the most of the time to drive only the going train to release cam 24. The cam 36 carries a projection 136 to operate the switch 50 to put the batteries in circuit as soon as the cam is started, and the projection 136 later operates a switch 151 for changing the signal circuit after the valves have warmed up. There is another switch behind the switch 50 for operating on the edge of cam 37. To start the going train a lever 52, Fig. 4, is rocked to the dotted position to move levers 54-56 which rotate an arm 57 which in turn rocks a lever 60 which moves a brush 61 away from the going train escapement 22 and engages a catch 161 with the release lever 26 to prevent the pin 28 from dropping into a notch 25 is a notch happens to be beneath. The lever 56 also moves a hook 63.adapted to drop into one of the notches 25, and the cam 24 which is loose on its arbor 23 carries a.pawl 64 driven by a ratchet wheel 65 on the arbor so that the cam 24 can overrun the arbor. When the start-. ing lever 52 is therefore operated, if the cam 24 is not in position to let the lever 26 push the pin 28 into a notch 25 the hook 63 will pull it into the appropriate position so that signals can commence at once. The edge of cam 37 is shaped to give an alarm, and to this end the lever 52 is moved counter-clockwise to rotate a toothed segment 75, the gear 76 being fast with an arm 77 on the end of which is a spring plunger 78 also operating on the slope 45 of the cam 37. This movement of the lever 52 to the left moves the arm 77 and the plunger 78 to the left and with it the cams 36, 37 to bring the cam 37 into the alarm position and slide the lever 41 laterally to free the balance wheel 44. When lever 52 operates quadrant 74 the going train is not released as only one sequence of the functional train is required. The alarm signal occupies only a part turn of the cam 37, and by starting the cam in this way the termination of the signal coincides with the end point of the movement where the arbor 43 stops the balance wheel 44 and the functional escapement 34. This initial rotation continues until a spring latch 79 on the back of cam 36 passes a pin 80 on the segment 75, which pin was moved to the dotted position, Fig. 4. The spring latches 79 and 81 will then engage the pin 80 and stop further movement. When the lever 52 is released a spring 82 will draw the segment 75 back and move the pin 80 to release the cams 36, 37. The arm 77 in rotating moves a spring lever 83 to flick and start the escapement wheel 44. A switch operating lever 96 is moved by a projection 89 on the segment 75 when it is moved to the alarm position, and this lever 96 disconnects the distress signal contacts and make the alarm contacts. The lever 94 is held in the alarm position by a pawl 98 and a pin 99, but when the cam assembly is within 30 degrees of its one revolution of travel a pin on the cam 37 releases the pawl 98 allowing the switch contacts to move back to the distress position in readiness for the next signal cycle. The external lever 101, Fig. 5 (not shown), operating the lever 52 is returned by a releasable catch operated by a push button, and a switch on the casing may connect the apparatus to a main or emergency battery on to an alternative supply or cut off. Specification 785,360, [Group XXVI], is referred to.