GB1478785A - Chuck with diaphragm-action clamping - Google Patents

Abstract

1478785 Chucks TOBLER SA MECANIQUE DE PRECISION FRANCO - SUISSE 7 March 1975 [12 April 1974] 9653/75 Heading B3B A chuck with a diaphragm-action clamping comprises a body 1, a diaphragm 2 with a central aperture mounted on the body, independent jaw carriers 5 firmly secured on the diaphragm, jaws 10 radially adjustable in the jaw carriers 5, and operation means 8 including a hub 7 which acts axially to deform the diaphragm elastically to tilt the jaw carriers to allow a workpiece P to be placed within or around the jaws 10 to be gripped externally or internally when the diaphragm is released, characterized by the provision of clearances between the shanks of screws 6 and apertures in the diaphragm in the clamping of the jaw carriers 5 to the diaphragm, and between a hub 7 and the central aperture of the diaphragm. The diaphragm 2 is held in the body 1 by a clamping ring 3. The diaphragm 2 includes an annular rib 21 against which the jaw carriers aer set. The jaw carriers include toe part 45 which engages behind a flange of the hub 7. The operating means 8 has operating clearances j and j 1 when the diaphragm is in the relaxed state to allow the chuck to be used for internal as well as external gripping. The jaws 10 are adjusted radially in the carrier 5 and gripped by a taper cotter 12 engaging a flat 10 1 . Alternatively the jaw shank may be threadably engaged with carrier (Figs. 4, and 5, not shown) and have two opposed flats for gripping by a cotter. The jaw 10 may be further supported by a bearing ring 11. The workpiece is pulled back on to abutments 16 during gripping. For internally gripping tubes (Fig. 6, not shown) peripheral workpiece abutments (17) are provided. The chuck body is centred on a machine arbor B. In the manufacture of the diaphragm the rear face (AR) (Fig. 7, not shown) is machined as a hyperbole to produce a straight front face generatrix (AV) in the relaxed and deflected states.