GB454098A - Improvements in or relating to vibration dampers of the friction disc type - Google Patents

Abstract

454,098. Vibration-dampers. TRIER, V. A., Andre Works, Victoria Gardens, Notting Hill Gate, London. March 23, 1935, No. 9124. [Class 108 (iii)] A frictional vibration - damper comprises plates A<1>, B<1>, Fig. 1, having conical friction surfaces inclined at an angle of between 10‹ and 20<0> to planes normal to the axis of the damper, the plates or sets of plates being movable to a limited extent relatively to each other about axes other than the axis of the central supporting bolt G which passes with clearance through apertures in the plates and is surrounded by an annular expansible chamber J formed partly or wholly of rubber &c. adapted when expanded by fluid-pressure to press the plates towards each other. The plates may be separated by a friction disc or discs D of wood &c. As shown in Fig. 1, the bolt G carries clamping members G, G<3> adapted to move with the plates A<1>, B<1> which are formed integral, alternately, with the arms A, B of the damper. Facing plates E of brass &c. are secured to the plates B<1> and formed with circumferential flanges E<1> between which and the edges of the discs D packing rings F are inserted. An annular housing H, H<1>, H<2>, H<3> containing the expansible chamber J is interposed between the uppermost plate A<1> and a clamping plate G<6>, the walls H<2>, H<3> having a limited axial movement relatively to the walls H, H<1> and to one another. The chamber J is formed by moulding the rubber around a disc-like core J<1>, Figs. 10, 11, comprising two annuli having bosses J<2>, J<3> through one of which fluid is forced to expand the chamber, e.g. under the driver's control in the case of a vehicle. In an alternative construction of chamber J a single metal &c. disc is provided, the pressure fluid being forced into spaces on opposite sides of the disc. In a modification of the vibration-damper one of the arms A, B is dispensed with and the corresponding plates connected by a bolt to a fixed bracket. In another modification, the wall H<1> is horizontal and the walls H, H<2> integral and movable relatively to the walls H<1>, H<3>, the wall H<3> bearing directly on the uppermost friction plate in order to vary the degree of friction when the clamping nut is tightened. The discs D may be made of wood machined to the desired conical shape or may comprise one or more annular laminations having a section between two radii removed, the disc being forced into conical shape when the damper is assembled. Where the disc comprises a plurality of laminations they may be glued together or separated by brass &c. interleaves. Alternatively, a single wooden layer may be backed with a conical packing piece of another material. In another construction, Fig. 3, a single friction plate M on one arm is secured between nuts N<1> to the bolt G and is clamped between the plates M<1> on the other arm by a star-shaped spring N<2> and the expansible chamber J, the outer wall of which abuts a pressure plate N<3> which bears against the nut P. In a modification, the spring N<2> is omitted, the plate M is movable relatively to the bolt G, and the clamping plate N<3> and adjacent end of the bolt are connected by an internally and externallythreaded nut by which the pressure of a spring acting between the nut and upper plate M<1> may be controlled in order to vary the degree of friction independently of the fluid-pressure device. Fig. 6 shows another construction in which the expansible chamber J and a spring Q<6> are arranged between friction plates Q, Q<1> on the arms, the plates being separated by discs Q<4> and facing plates Q<5>. Fig. 7 shows a further construction in which the degree of friction is varied by fluid pressure in an expansible chamber comprising integral walls S, S<1>, S<2> and a relatively movable wall S<3>, a reinforced, annular, flanged, rubber disc V<1> clamped to the wall S<2> bearing on the wall S<3> when fluid is injected through a pipe W into the space between the walls S, S<1>, S<2> and the disc.