GB1058502A - Mounting abrasive disks on a drive member - Google Patents

Abstract

1,058,502. Abrasive tools. MERIT PRODUCTS Inc. May 6, 1965, No. 19214/65. Heading B3D. An abrasive tool comprises a rotary drive member 26 having a socket formed of a non- circular drive structure 44 which is adapted to receive a non-circular hub structure 48 united with an abrasive disc 20, the drive structure and hub structure being axially engageablo and separable in a first relative rotary position in which the hub structure is loose with respect to the drive structure and being rotatable to a second relative position which is a limit position and in which position shoulders on the drive member and hub structure are positively engaged to prevent axial separation of the member and structure. The abrasive disc 20 consists of a layer of fabric on which is bonded a layer of abrasive particles and a backing layer of fibreboard. The hub structure 48 (Figs. la and 2) is of plastics material and of annular shape, the inner bore of the annulus being a snug fit on a boss (35) extending from the drive member and the outer surface being of hexagonal shape. The annulus is formed with slots (54) to provide six segments each of which has surfaces (60, 62) and the inner surfaces of the segments are provided with inwardly-extending flanges 50. The drive member has a circular body 28 secured to an elastomeric flange 30 for backing the abrasive disc. The body 28 has a sleeve 44 which forms the non-circular drive structure and has six recesses (45, Fig. 2) forming projections (46). When the abrasive disc is presented to the hub structure, the segments embrace the boss 35 and the flanges 50 enter a groove 36 therein. When the disc is rotated relative to the drive member surfaces on the projection on the sleeve engage the surfaces on the segments 55 to retain the flanges in the groove to lock the disc to the drive member. In another embodiment, the sleeve 44 is replaced by a series of pins (65, Fig. 3a). In a further embodiment, the sleeve has an oval opening and the hub structure is oval, Fig. 5 (not shown). In another embodiment in which locking is effected in only one direction of rotation, the sleeve 44c, Figs. 6 and 7 (not shown), has recesses 74 having radial 78 and inclined faces 80 and the hub structure has segments having similar faces 75, 76 so that in one limit position the inclined faces engage to lock the disc to the drive member and in the other limit position, the radial faces abut but permit axial separation of the hub and drive member. In another embodiment, the drive member 84, Fig. 9 (not shown), carries a magnet 92 within a sleeve 88, Fig. 11 (not shown), of hexagonal shape, and the abrasive disc 86 has a stamping 97 having a flat wall 98 to lie against the wall and a hexagonal peripheral wall 100. The drive structure also has a pin 95 carrying a head 96 of triangular configuration which can pass through a triangular shaped hole in the wall 98. In use, the wall 100 abuts the sleeve 88 and the triangular head is displaced relative to the hole to prevent axial separation of the disc and drive member.