GB1279539A - Improvements in or relating to clamping devices - Google Patents

Abstract

1279539 Chucks; mandrels J TOBLER SA 2 April 1970 [6 Aug 1969] 15686/70 Heading B3B A device for clamping a workpiece 8 in a machine tool comprises radially movable clamping blocks 4 which are moved by ramp surfaces 3<SP>1</SP> of a control member 3. Initial axial movement of the control member 3 radially grips a workpiece 8 and further axial movement thereof moves a surface 8<SP>1</SP> against a reference surface 1<SP>1</SP> of a body plate 1 of the device. A spring 6 biases a movable sleeve 2 against the direction of clamping movement of the control member 3. A clearance a is less than a clearance b so that slippage occurs between the blocks 4 and the workpiece until a flange 2<SP>1</SP> abuts an end surface 7<SP>11</SP> of a member 7. In a second embodiment (Fig. 2, not shown) a narrow workpiece is axially clamped by providing a detachable clamp member on the end of sleeve 2. In a third embodiment (Fig. 3, not shown) axial clamping surfaces are formed on a radial flange of the blocks 4. In a fourth embodiment (Fig. 4, not shown) the clamping blocks are moved radially inwards to grip a male workpiece, the ramp surfaces being provided on the sleeve 2. In a fifth embodiment two workpieces are gripped together on a sleeve 2 that houses a spring-biased control member 3 1 and a second axially movable control member 3, the two control members operating two sets of radially movable clamping blocks 4.