GB870781A - Improved rotary power transmission shaft - Google Patents

Abstract

870,781. Shafts; resiliently-mounted racerings. GENERAL MOTORS CORPORATION. Sept. 25, 1959 [Sept. 26, 1958], No. 32665/59. Addition to 839,292. Class 80 (2). [Also in Groups XXXI, XXXII and XXXIV] The drive-transmitting shaft 1, Fig. 1, of the parent Specification, which is normally straight but is held bowed in operation by bearings 9, 11 comprising, as shown, a crank-shaft bearing and a differential gear bearing in a motor car transmission, is modified by the provision of vibration absorbing devices 17, 19, Fig. 6, to control bending vibrations in the shaft at its second mode critical speed or a sub-harmonic of this speed. The vibration dampers may comprise masses 15 secured for rotation with the shaft 1 by dashpots 17 alone, or dashpots 17 in combination with springs 19. Alternatively, Figs. 10-13 (not shown), the vibrations may be absorbed by non-rotary dashpots or similar devices connected between the shaft 1 and stationary parts of the car, the dashpots then being mounted by bearings on the shaft. As a still further modification, Figs. 14, 15 (not shown), magnetic vibration damping devices may be employed. In one construction, a rotary mass 31, Fig. 16, is connected by rings 41 of butyl rubber to a sleeve 39 itself connected by rings 37 and set-screws 38 to split-rings 35 enclosing rubber shims 33 sourrounding the shaft 1. Each of the butyl rubber rings 41, which both act as springs and absorb vibrations, is formed with holes 43, Fig. 17. In another form, a non-rotary mass 59, Fig. 18, connected to the motor-car frame by a strut 61, surrounds a ball-bearing 51 within which rotates a sleeve 58 mounted through butyl rubber &c. rings 47 on a sleeve 45 in turn mounted through shims 35 of rubber upon the shaft 1. In another similar construction, a non-rotary mass 72, Fig. 19, again attached to the car frame by a strut 61, is connected by rubber rings 69 to a non-rotary housing 65 supporting a ball-bearing 51 the inner race of which is mounted upon a metal sleeve 64 and a rubber sleeve 63 fitted upon the shaft 1. In yet another construction, a stationary housing 77, Figs. 20, 21, contains a mass 79 of rubber acting as a vibration damper and surrounding a non-rotary casing 75 enclosing a ball-bearing 51 mounted by a sleeve 73 upon the shaft 1. In another, similar construction, an outer ring 89, Fig. 22, secured to the car frame, encloses a rubber ring 85 forming an annular chamber 87 filled with silicone fluid or a similar viscous medium. A needle roller bearing 83 connects the rubber ring 85 to a metal ring 81 upon a shim 73 carried by the shaft 1. The silicone &c. fluid provides damping additional to that of the rubber ring 85.