GB190908761A - Improvements in or relating to Variable Speed Gears. - Google Patents

Abstract

8761. Dubrul, A. April 13. Driving machines. - Variable-speed gearing, of the class comprising tapering friction gear members adapted to be shifted angularly to alter the point or zone of gear contact, has the engaging-surfaces grooved to increase friction. A " roll " 1, Fig. 1, on a fixed driving-shaft 4, is adapted to drive a roll 2 on a driven shaft 5. The roll 2 has a curved contour, so that, by altering the inclination of the axis of the roll 2 to that of the roll 1, the velocity-ratio may be varied. The shaft 5 is for this purpose divided, and the ends of the portion carrying the roll 2 are supported in slide blocks 6, which may be moved relatively to one another. The blocks 6 have pins 8, Figs. 3 and 5, engaging oppositelyinclined cams 9, 9<a> secured to a rock-shaft 10. The shaft 10 is connected by a lever 11, Fig. 3, and a link 12 to an operating-lever 13 capable of perpendicular movements about pivots 14, 47, Figs. 1 and 5. A movement of the lever 13 transverse to the shaft 4 thus tilts the roll 2 to vary the speed. For reversing, cylindrical rolls 24, 25 are provided on the shaft 4, and on the other portion of the shaft 5, respectively. To effect reversal, the roll 2 is moved bodily back from the roll 1, and the rolls 24, 25 are connected by an idler 26. The shaft 5 of the roll 2 and the spindle 27 supporting the idler 26 are for this purpose mounted at both ends in eccentrics 37, Fig. 3 and 28, Fig. 5, respectively, the pairs of eccentrics being connected by links 39, 29, &c., and rock-shafts 41, 31. A yoke 48 surrounds the lever 13 and is slotted to allow the transverse movement already described to take place freely. Links 43, 33, Fig. 1, connect this yoke 48 to the shafts 41, 31, respectively, so that a movement of the lever 13 to the left or right of Fig. 1 advances the roll 2 or the idler 26, as the case may be, into driving-engagement, the other of these gear elements being simultaneously withdrawn. The parts of the shaft 5 are connected through two universal joints 15, Figs. 1 and 6, connected through a coupling 16 which allows relative longitudinal movement. One of the blocks 6, Fig. 3, is connected through links 21, 19 to a rod 17, Fig. 1, which slides over a scale 18 on the lever 13, as the roll 2 is tilted, and serves as a speedindicator. The lever 13 may be moved transversely by hand, or automatically through a link 50, Fig. 1, the latter arrangement being specially applicable where the link 50 is a cross-feed member in a metal-working machine.