Patent GB-594971-A (GB)
Title: Improvement in bevel gear holding fixture
IPC: B24B41/06
Filed: 1944-12-29
Abstract: 594,971. Chucks. BRYANT CHUCKING GRINDER CO. Dec. 29, 1944, No. 26116. Convention date, Dec. 20, 1943. [Class 83 (iii)] [Also in Group XIX] In a chuck or work-holder for supporting toothed bevel gears during machining or gauging operations which are concentric with the pitch cone, the teeth are engaged by discs spaced around the holder and having bevelled edges for engaging the tooth flanks in predetermined relation to the pitch cone. In one form a bevel gear 12, Figs. 2 and 3, is engaged by bevelled discs 10 which are held against accurately machined surfaces 8, 9 on a chuck body 5 by an internal ring 13 and an annular plate 20 held to the body 5 by screws. The discs 10 are spaced circumferentially by segments 15, Fig. 1, clamped to the body by screws 16. The gear 12 is held in contact with the discs 10 by diametrically opposed levers 25 pivoted at 28 on a ring 30 connected by a pin 40 to a draw spindle 32, the action being such that rearward motion of the draw spindle causes bevelled surfaces 46 on the levers to engage cam surfaces 45 on the chuck body and contract them over the work, whereupon further motion draws the levers axially to clamp the work. The levers are expanded on forward motion of the draw spindle by springs 50 and the ring 30 may rock on the pin 40 to equalize the pressure of the levers. The discs 10 may consist of two spaced rings with inner bevelled surfaces for engaging opposite faces of a tooth on the work and may be held axially in position by spindles engaging slots in the segments 15. In a modification the discs 10a, Fig. 10, are held against the centring surfaces 8a, 9a, by levers 80 held on the chuck body 5a by screws 82 and having bevelled ends 81 engaging the discs and slotted ends 85 engaging pins 86 on the body. In another modification the discs 10b, Fig. 13, are held by lugs 91 on a ring 20b clamped to the body by screws 92 and the work-clamping levers have bevelled ends for engaging a conical surface 90 on the work. In another modification the discs are held by a conical portion 95, Fig. 15, on a central sleeve 96 secured in the chuck body by a nut 98 and the levers 25c engage an end surface of the work 12c, whilst in another modification the discs 10d, Fig. 17, are retained by a conical interior surface 8d on the body and a central cylindrical sleeve 110 secured by a flange 101 on a screwed bush 102, the levers 25d then engaging an annular surface 105 on the work 12d. Alternatively the work 12e, Fig. 19, may.be engaged by discs 123 in a carrier 120 which may be gripped in a chuck 1 with either end projecting so as to facilitate machining either end of the work as by a grinding wheel 55, The discs are held in the carrier by the conical end of a sleeve 129 and a nut 127 and the conical exterior of the work is engaged by the inclined ends 131 of jaws 130 having shanks 135 slidable through flanges 136 of the carrier 120. Springs 140 urge the jaws to clamping position and abut on nuts 137 which are screwed on the shanks 135 and are locked by screws 138 co-acting with split ends of the shanks. The carrier is gripped in the chuck by three jaws 150 engaging bevelled surfaces 151 and moved axially by a flange 157 on a draw spindle 158.