GB465081A - Improvements in or relating to continuously-variable mechanical change-speed gears - Google Patents

Abstract

465,081. Variable-speed ratchet gearing. WICHA, A. May 25, 1936, No. 14774. Convention date, June 1, 1935. [Classes 80 (ii) and 80 (iii)] [Also in Group XXVI] A driving shaft 2 carries a compound adjustable eccentric 13, which gyrates a disc 14, mounted freely on the eccentric 13 and prevented from rotation by an arm 17, the disc 14 having radial slots engaged by one-way devices 20, which grip an annular flange or flanges, carried by a built-up gear-wheel 25 driving a pinion 28 on the driven shaft 29. The eccentric, which is adjustable to zero throw, comprises an outer eccentric sleeve 13, mounted on an inner eccentric sleeve 11, the eccentricity of the outer sleeve 13 to the inner 11 being equal to that of the inner sleeve to the shaft 2. In the form shown in Figs. 1 and 2, the outer sleeve 13 is screw-threaded on the inner, and the latter is splined on the shaft 2 and is adjusted axially by means of a handle 40, adapted to turn a sleeve 41, having internal axial teeth engaging axial gaps in the screwthreaded periphery of a sleeve 36, which sleeve engages a fixed screw-thread in the casing, and is carried on a ball thrust-bearing by the eccentric sleeve 11. The one-way devices engaging the slots 19 in the disc 14, comprise wedges 20 or rollers, co-operating with additional jamming rollers 21, the wedges and rollers being supported on each side of the disc in annular grooves in the wheel 25, in which grooves they are adapted to jam. Light springs 21<1> press the rollers into jamming engagement with the wedges. The tangent of the wedge-angle alpha is less than the coefficient of friction between the annular grooves and the rollers. In the modification shown in Figs. 4 to 6 the adjustable eccentric comprises an inner eccentric 45, fixed to the driving shaft 44 and an outer eccentric 46, turned thereon by engagement with a peg 62, carried by a sleeve 61, screw-threaded on the shaft 44, and turned by axially moving it, under the influence of a bolt 66, screwing through a thrust-collar 65. The eccentric freely carries a gyratory disc 47, prevented from rotation by an Oldham connection 49 with the casing. Radial slots 52 in the gyratory disc 47 are engaged by tongues 53, Fig. 6, of one-way devices, comprising grooved sleeves 54, receiving an axial flange 56 on a driven disc 57 and internal wedging rollers 60, lightly pressed into jamming engagement, between the flange and sleeves either by springs 59<1> or additional small rollers 59.