GB1137912A - Improvements in or relating to collets - Google Patents

Abstract

1,137,912. Hand tool handle fixings. U A ENG. Ltd. 1 April, 1966 [4 Jan., 1965], No. 221/65. Heading B4K. A tool shank 9 is attached to a handle 2 by a collet which comprises outer and inner tubular sleeves 1, 5 which are relatively rotatable without relative axial movement or relative eccentric movement, the outer sleeve 1 having a cam formation to provide the gripping action. The tool shank 9 has a projecting cross pin 10 the ends of which are located in corresponding recesses 13 in the end of the handle member 2 to prevent rotation of the shank. The inner sleeve 5 has diametrically opposed jaws 7 in the form of integral flexible tongues. Rotation of the outer sleeve 1 acts through cam formations 8, Fig. 3 (not shown), to move the tongues 7 inwardly to grip the shank 9, the inner ends of the jaws 7 engaging in front of the cross pin 10. In a modification the cross pin is omitted, the shank being formed to a non- circular profile and the bore of non-circular cross-section. In another modification, Fig. 5 (not shown), the inner sleeve 5 is located in the tubular handle 2 by a set screw 3, one end of the inner sleeve having a shoulder 14 of enlarged diameter, the annular periphery of which engages an annular abutment on the sleeve 1. The outer sleeve 1 has an enlarged nose 6. The annular surface surrounding the point where the central bore in the outer sleeve 1 breaks into the inside of the latter has an axially inwardly facing cam formation 16 which engages the cross pin 10 and grips the latter between the cam formation 16 and an arcuate depression formed in the outer end surface of the shoulder 14.