GB1469115A - Brake discs - Google Patents

Abstract

1469115 Brake discs; reducing noise GENERAL MOTORS FRANCE 22 May 1975 [30 May 1974] 24056/74 Heading F2E A brake disc 1 for a disc brake has in its outer periphery a circumferential groove 2 having a base surface 4 and two wall surfaces 3, into which groove 2 is fitted an annular member 5 with at least one surface thereof in frictional contact with and bonded by a resilient cement to, one of the surfaces of the groove 2 so as to allow some degree of resilient movement between said one surfaces of the annular member 5 and the disc 1, whereby, when the disc 1 is exposed to vibration in use, the frictional forces generated between the surfaces alternate the vibration and decrease its audibility. By resilient cement is meant an adhesive, for example a heatresistant epoxy resin cement which, after setting, permits some slight degree of freedom of movement between the secured surfaces without breaking the adhesive bond. In the embodiment of Fig. 2, the wall surfaces 3 are parallel and the annular member 5 comprises two ring-shaped laminµ 6 stacked in the groove 2 with their flat radial surfaces forming frictionally-contacting surfaces; these surfaces are bonded by resilient cement and the radial surfaces contiguous with surfaces 3 are bonded thereto. In the embodiment of Fig. 3 (not shown) the groove (2) has radially inwardly converging side surfaces (3) and the complementary shaped annular member (5) has its side surfaces (7) bonded thereto. In the embodiment of Fig. 4 (not shown) the annular member (5) comprises two rectangular cross-section rings (6) of different diameters placed one upon the other and bonded to one another and with the radially inner ring bonded to the base surface (4). A clearance (8) is left between the sides of the rings (6) and surfaces (3). The embodiment of Figs. 5, 6 shows an annular member of waved contour with the surfaces 9 being bonded to the side surfaces 3. In the embodiment of Fig. 7 (not shown) an annular member of waved contour form has its crests (10) lying on the inside circumference of the annular member and bonded to the base surface (4), and a clearance is provided between the member (5) and the side surfaces (3). The annular members could be in the form of closed loops, open loops or comprised of separate segments evenly distributed around the groove, the annular members may be of metal or synthetic resin material. More than two laminµ bonded together could be used in an annular member-the resilient cement could be applied over the whole area of the contiguous surfaces of the laminµ, or could be applied at certain areas only. Each lamina could be formed from separate segments cemented to one another.