GB833048A - Improvements in or relating to chucks - Google Patents

Abstract

833,048. Chucks; boring-heads. SYKES, A. E. April 29, 1957, No. 13524/57. Class 83 (3). A chuck has an open-ended hollow body 10, Fig. 1, housing a thin-walled lamella or sleeve 14 which is distorted by fluid-pressure to grip a tool or workpiece. The sleeve 14, having a flange 15, is sealed to the body 10 at 19, 20, and fluid medium is forced from a bore 21 of the body 10 through a passage 25, by a screw 23 in the bore, rotatable by hand at 24. This fluid-pressure acts between the sleeve 14 and body 10 to contract the sleeve on to a collet 18 engaging the work &c. In a modification, a sleeve 26, Fig. 2, in the bore 13 is sealed at 20, 27 to the body 10, the seal 27 being held by a disc 28 and screw 29. Pressure is exerted on the sleeve 26 by fluid expelled from one or more bores 30 and passages 31, by plungers 32 actuated by a cap 33 screwing at 35 on the body 10. In a further modification, fluid is supplied through a hollow spindle to the passage 25 from an external source. In another modification of the form of Fig. 2, the bores 30 are formed in a sleeve whose outer and inner surfaces are deformed by the fluid-pressure against the outer body and an inner collet. An additional modification has springs urging balls against plungers to facilitate positioning thereof. The pressure may be regulated, in the above embodiments, to allow slipping of the collets on excessive torque occurring, or radial plungers may be depressed by internal cams on a rotatable sleeve having graduations to indicate the slipping torque required for screw-cutting taps. The collets and sleeves may be tapered internally or externally. In another modification, a boring-tool 55, Fig. 6, held in an eccentric-bore 57 in the collet 54, has its cutting-edge 56 adjusted radially by rotation within bore 57. The adjustment is registered by a pointer 63 reading against a scale 64. The collet is held against rotation in the body 10 by a pin 60, and is closed by fluid-pressure applied by any of the above constructions. Specification 802,278 is referred to.