GB698208A - Oscillation damper - Google Patents

Abstract

698,208. Frictional vibration-dampers. GRANET, C., and ROLAND, G. April 3, 1951 [April 6, 1950; Oct. 19, 1970], No. 7755/51. Class 108 (iii). The rotor 2, Figs. 1 and 2, of a frictional oscillation vibration-damper is made entirely or partially of resilient material and has at least one protuberance or boss 3, the stator 5, 6, 7 having means capable of rendering progressive the friction-damping action for either direction of rotation. In the construction shown in Figs. 1 and 2, the rotor 2 has three bosses 3 spaced at 120 degrees and co-operating with respective, similarly-shaped recesses 8 formed in the stator body 7. On deflection in either direction from a normal neutral position (shown), each boss is compressed as it passes from its recess 8 into an escape recess 10 within which it is able to move freely. Deflection is limited by axially-disposed rotor projections 4 which correspond with similar projections 11 formed on the stator end-plate 6. Friction between the opposed side-faces of the rotor 2 and stator end-platc 6 is adjustable by the action of a nut 12 bearing on angularlyspaced fingers 14. A spring-loaded ball 18 in each finger, co-operates with a respective indexing recess in the nut 12. In a modification, Figs. 5 to 7, two rotor portions 2a, 2b each identical with the rotor 2 of Figs. 1, 2 are rigid, but angularly spaced, with respect to each other, so that a boss 3a on the portion 2a lies equidistant from adjacent bosses 3b on the portion 2b. The stator body 7 is formed with a pair of correspondingly angularlyoriented series of recesses 8a, 8b, each identical with the series of recesses 8 of Figs. 1 and 2. The stator body 7 is also formed with a pair of series of escape recesses 10a, 10b corresponding to the recesses 10 of Figs. 1 and 2. Deflection is limited by the action of an axial projection 4a. The portions 2a, 2b may be formed integrally, Fig. 9 (not shown), and a greater number of portions may be employed in conjuction with a corresponding number of stator recess series. The projections 3a, 3b may be assymetrically disposed in relation to the stator recesses so as to produce an initial friction force in the neutral position. In another form of construction, Fig. 3 (not shown), the bosses may project axially from the side faces of the rotor tn co-operate with recesses formed in side plates secured by bolts to the stator. A plurality of axially-disposed rotors may be assembled on a common operating shaft, Fig. 4 (not shown), each with a respective pair of recessed side-plates. A combination of the constructions of Figs. 1 and 3 (i.e. having both peripheral and axially-disposed bosses) may be employed. The rotor may be of natural or synthetic resin.