GB444222A - Improvements in or relating to vibration damping devices - Google Patents

Abstract

444,222. Vibration-dampers. SARAZIN, R. R. R., St.-Prix, Seine & Oise, France. Jan. 22, 1935, No. 2107. [Class 108 (iii)] In a vibration-damping device comprising a mass movably supported upon the vibrating part by one or more rolling members, each of which rolls on a track carried by the vibrating part and on a track carried by the mass, the rolling member is a circular or non - circular cylinder and rolls with its outer surface on the roll. ing tracks of the vibrating part and of the movable mass respectively. A disc 2 secured to a shaft 1 has slots in which is mounted a weight 3 having pins 5 of smaller diameter than recesses 6 in the disc 2. The pins 5 and recesses 6 are formed with cylindrical bearing surfaces 7, 8 on which run rollers 9 which form the connecting members between the shaft 1 and weight 4. A weight 11 mounted in a recess 10 in the weight 3 and urged by a spring against the disc 2 prevents relative motion between the weight and the shaft at low velocities. The weight 11 moves outwardly when the shaft 1 rotates at high velocity thus freeing the weight 3 for movement relative to the disc 2. In a modified construction, Fig. 5, a member 2, attached to the shaft 1 has spaced lugs between which the ends of the weights 3 are mounted. The central part of the roller 18 rolls on a hardened sleeve 17 mounted in the weight and each end portion of the roller has a bush 19 on which is freely rotatable a sleeve 20 which rolls on a hardened sleeve 15 mounted in a recess 14 in the lug. To prevent jamming at low velocity each weight is provided with two studs of which the ends are adjustably set near the surface of the member 2. In a modification of Fig. 5, Fig. 6 (not shown), each rolling member is provided with toothed rims secured to the roller by a key and shrunk on to the central portion of the roller. A central toothed rim co-operates with teeth formed on an annulus secured to the added weight. For damping longitudinal vibrations in a crank-shaft, the disc 2 is supported on the crank-shaft in a plane passing through its longitudinal axis, and the mass 3 vibrates in a direction parallel to that plane. The rolling member may have a non circular cross-section and the rolling tracks may be other than circular and of different curvatures. Lubrication is effected from an axial bore 23 associated with a passage 24 in a bolt 25 and connected to a passage 26 in the member 2.