GB233754A - Improved gearing mechanism - Google Patents

Abstract

233,754. British Thomson-Houston Co., Ltd., and Tuppen, E. B. Jan. 19, 1924. Toothed, belt, and chain gearing.-Relates to gearing for producing a cyclic variation of speed so that the driven member periodically slows, stops, or reverses, particularly applicable to electric switch gear and controller gear in which it is desired that a switch arm or the like shall pause momentarily on each contact. In the form shown in Fig. 2, the driven wheel 2 turns on a fixed pivot 1, about which swings a frame 8 carrying a driving-wheel 3 gearing with the wheel 2. A crank-pin 5 on the wheel 3 is connected by a link 6 to a fixed point 7 and the wheel 3 is rotated at constant speed bv a universally jointed shaft. The wheel 2 is constrained by the links 6, 8 to swing about the pivot 1 and, when the pin 5 is arranged upon the pitch circle of the wheel 3, the wheel 2 is driven at a varying speed falling intermittently to zero. If the pin 5 is arranged respectively within or without the pitch circle of the wheel 3, the velocity of the wheel 2 either does not fall to zero or is temporarily reversed during each cycle. Other means may constrain the wheel 3 to swing about the pivot 1 and the pin 5 to move radially to the wheel 2. The toothed gearing may be replaced by chain or belt gearing. As shown in Fig. 6, the wheel 3 may be driven by a concentric wheel 14 secured thereto and gearing with a driving-wheel 15 loose on the pivot 1. This drive produces a fluctuation in the speed of the wheel 3, which is, however, small when the wheel 14 is large, and by suitably arranging the pin 5 with relation to the pitch circle, of the wheel 3, the effect of the fluctuation may be overcome and the desired motion obtained.