GB364925A - Improvements relating to collets - Google Patents

Abstract

364,925. Chucks. MATTHEWS, M. J., 3583, Beniteau, Detroit, Michigan, U.S.A. March 5, 1931, No. 6935. Convention date, March 12, 1930. [Class 83 (iii).] In a collet, constructed to ensure that the gripping faces of the jaws contact along the whole of their length with various sizes of work pieces, the jaw members are radially slidable on a shank member. A tubular shank 8 stepped down at 10 has two opposite annular sockets 11, 12 in which are loosely pivoted trunnions 13, 14 of a pair of semicircular sleeve pieces 15, 16. Each of the sleeve pieces is provided with two extending trunnions 19, 20 which engage recesses in a pair of jaw members, there being four gripping jaws in all; the edges of the intermediate members 15, 16 are cut away, Fig. 2, to give a limited rocking movement to the jaws. The jaws, having bevelled outer faces, are kept in contact with the complementary bevelled face of a hollow spindle 38, Fig. 1, by a spring ring 26. If the bar being gripped is slightly out of round the two opposite jaw members engaging the larger diameter move inwards by reason of the rocking action of the members 15, 16 and the other pair of jaws will move outwardly so that all four jaws grip the work with equal pressure. A modification consists in connecting the gripping jaws by trunnions directly to the shank 8 without employing intermediate members 15, 16.