GB422076A - Differential transmission mechanism for meters, clocks, and other purposes - Google Patents

Abstract

422,076. Differential gearing. MAAG, W., 128, Albisstrasse, Zurich, Switzerland. Oct. 19, 1933, No. 28982. [A Specification was laid open to inspection under Sect. 91 of the Acts, April 23, 1934.] [Class 80 (ii)] [See also Groups XIX, XVIII, and XXVI] A transmission mechanism for actuating a counting-apparatus and for other purposes comprises differential wheel gears driven by two different sources and so coupled together as to drive a shaft in accordance with the difference in movement derived from the two sources. The driven shaft may actuate a counter or operate a switch or other control mechanism. The invention is applicable to prepayment meters, to apparatus for synchronizing alternating current generators and motors, and to means for synchronizing clock installations. As shown in Fig. 1, two sun wheels 2, 3, driven in the same direction from two different power sources, are loosely mounted on a shaft 1 and drive planet wheels 4, 5, to transmit movement through sun wheels 6, 7 to a common pinion 13 secured to a shaft 14. The planet wheels are mounted on shafts 8, 9 secured to a hollow shaft 10 on which the sun wheels 6, 7, are loosely mounted. The shaft 14 actuates a counter 15 or may operate a switch to open to close a circuit when the shaft is moved into a normal or zero position. As applied to a prepayment meter for radio apparatus. The insertion of coins into the meter and the operation of sun wheel 2 will cause the counter 15 to indicate the number of coins inserted. Switching on the radio apparatus will release a clockwork to drive the sun wheel 3 and cause the counter wheels to return to zero position whereupon a switch arm or cam on the shaft 14 will interrupt a circuit in the apparatus. In cases where the force acting on the sun wheel 2 or 3 is insufficient to effect its movement an auxiliary force may be employed. This auxiliary force acts to rotate the shaft 1 and to store up energy in an elastic member such as a spiral spring connected at one end to the shaft and at the other end to a ratchet wheel integral with the sun wheel. The movement to be counted is effective to release a pawl from the ratchet wheel and the tensioned spring causes the sun wheel to move. As shown in Fig. 2 applied to a clock installation comprising a master clock 20 and a secondary clock 21, the master clock is driven by a spring barrel 23 and regulated by a pendulum acting on a wheel 24 while the secondary clock is driven by a source of power such as an electric motor. A difference in the two movements is indicated by the numeral wheel 15. For synchronizing alternating current generators or motors 30, 31, Fig. 3, the shaft 14 driven through the differential gear operates a regulating member 32 controlling a switch 33 with co-operating contacts 34, 35 in regulating circuits.