GB189905112A - Improvements in Gear for Transmitting Motion. - Google Patents

Abstract

5112. Mallet, P. March 8. Motor road vehicles, variable-speed and reversing gearing for. The transmission is effected through roller-and-disc friction gear and worm and wheel gear ; the thrust of the worm is taken by springs, so that, as the resistance increases or diminishes, the worm and its shaft with the friction roller are caused to move axially, and thus to vary the radius of contact of the roller with the disc, and thereby the ratio of the transmission. Referring to Figs. 5, 7, and 10, the friction discs b, c, driven from the shaft a, press upon a loose roller 1 and a fixed roller d upon the shaft e, which is formed with a worm f, in gear with a wheel g on the driven shaft h. The worm is supported between rollers 51 ; its thrust is taken by springs s, which are connected by racks and pinions to a lever working against an adjustable stop, whereby the movement of the springs to the right, and hence the maximum speed, may be regulated. The shaft carries a cone j which, as it moves to the right, under diminished resistance and with increase of speed, comes into contact with a fixed hollow cone q which forms a brake. The movement of the shaft to its extreme position to the right also brings a clutch on the face of the roller d into gear with a clutch on the wheel of an epicyclic train mounted on the end of the driving-shaft a, the carrier-wheel 17 of which may be locked or retarded by means of a brake, for the purpose of driving the shaft e in the reverse direction. The engagement of the brake j, q is regulated by a lever 3 acting upon a sleeve r which bears upon the cone i. The discs b, c are driven by friction rollers 28 and toothed wheels 26 from a pinion 25 on the shaft a; they are mounted on taper spindles, the bearings of which pass through the frame, and are threaded to receive nuts 44, 45 by which they can be adjusted to set the discs with the desired pressure against the roller d. The driving-treads on the backs of the discs are provided with set-screws, by which they can be forced away from the discs to compensate for wear &c. 29 are counterpressure rollers, and 31 are pressure discs on spindles 32 pressed up by hand-operated levers acting on blocks 38 fitted to slide in the frame. The bearings of the spindles are adjustable in the vertical plane The arrangement of the brake for the carrier disc is shown in Fig. 7. In Fig. 10, the wormwheel g is shown as the carrier wheel of a compensating-gear, the main wheels 77 of which are mounted on squares on the shafts h, and with their bosses extending between the boss of the worm-wheel and the shaft bearings in the frame sides. In a simpler form of the mechanism, the discs b, c are driven from the shaft a by bevel gearing ; they are pressed up by springs on their spindles, which springs by a system of cranks and levers serve also to receive the thrust of the worm. In the modification shown in Fig. 13, the discs b, c are formed with extensions provided with friction surfaces 94, which gear directly with the edge of the flywheel 6 on the driving-shaft, or with that of a movable disc pressed up by a spring. The rollers d, 1 are both loose on the shaft e, but either of them may be connected to it by a clutch placed between them. The discs are pressed up by flat springs, which bear upon the other ends of the cylinders 113, which enclose the bearings, and are drawn together by adjustable tie-rods.