GB787505A - An improved mechanical infinitely variable torque converter - Google Patents

Abstract

787,505. Variable-speed gear. AUTO UNION GES. March 2, 1954 [March 3, 1953], No. 6098/54. Class 80 (2). In a variable-speed gear, for a motor-vehicle, of the kind in which masses 17, 20 are rotated by an input shaft 5 about eccentric axes on an intermediate shaft 12 spring-coupled to an axledriving output shaft 23, such rotation developing alternating opposite drive impulses of which those in the direction not required are suppressed by a one-way detent, the said detent comprises a helix, e.g. 27, embracing the shaft 12, secured at one end to the fixed housing 7, and having coupling means for moving its other end into frictional engagement with the shaft 12. As shown, two detent helices 27, 28 of exponentially tapered cross-section are provided, acting in opposite directions under the selective control of a forward, neutral, reverse and park-lock lever 40, which allows the free end of either one helix to be contracted into contact with the shaft 12 whilst simultaneously expanding that of the other, by oppositely turning flared sleeves 33, 37, each surrounding a helix and connected to its free end by a light spring 31 which gives the helix end an initial contracting stress. Lever positions 41, 42, 43 give forward, neutral and reverse, whilst the transverse position 44 allows both detents to act simultaneously for parklock. The helices 27, 28 may be formed by slitting a tube and may be single or double start. In Fig. 1 the masses 17, 20 are formed on planets 16 carried by the intermediate shaft 12 and meshing an internally toothed ring 22 on a flywheel 8, driven through chain reducing gear 3 by an engine 1. In Fig. 6 (not shown) the masses are carried on arms linked together and to a crank-pin on the flywheel 8, whilst in Fig. 7 (not shown), the masses are on planet-sprockets chain-geared to an input sun. The spring coupling connecting the intermediate and output shafts 12, 23 comprises a single rectangular sectioned forwardly tapered torsion bar 45, secured to the output shaft 23 and engaged by internal driving ribs 46, 47 on the intermediate shaft 12 over a contact length which increases . with increased deflection, due to the taper of the bar. Maximum deflection is 180 degrees divided by the gear-ratio (4 to 1). In Fig. 4 the torsion bar 45a has three laminations which successively contact steps of driving ribs 46a, 47a. In Fig. 8 the shafts 12, 23 are coupled by a helical torsion spring 65 of taper cross-section, surrounded by a flared sleeve 67. The spring is contracted by relative forward acceleration of the shaft 12 and expanded by its retardation.