GB1440865A - Clamp - Google Patents

Abstract

1440865 Welding by pressure CLARKE CHAPMAN Ltd 3 Feb 1975 [19 April 1974] 17201/74 Heading B3R A clamp comprises a base 10, an actuator 12 fixed in relation to the base, first and second jaws 14, 16 supported by the base, the first jaw and a bar 18 being movable in the same direction by the actuator and the second jaw being movable in opposition to the first jaw by a lever 20 pivoted to the base and angularly movable by the bar. In an embodiment the actuator is a hydraulic ram having its cylinder secured to the base and its piston-rod connected to a member 34 with a head located in a recess 36 in one end of a block 38. The first jaw 14 is secured to the other end of the block, which block is connected on its underside with the bar 18 by a key and screws. The bar 18 is located in a horizontal channel in the base and at its end remote from the ram engages a roller 106 on one end of the lever 20 pivoted at 104 to the base. The other end of the lever carries a roller 102 which engages a lug 94 secured to one end of a block 381 slidable on the base and carrying the second jaw 16 at the other end. Links 98, 110 connect the lug and the bar with the pins on which the rollers are journalled. The operation of the ram moves the first jaw and the bar and the latter causes rotation of the lever 20 to cause equal and opposite movement of the second jaw. The clamp may be arranged between two slides on the base of a friction welder. The workpiece 22 may engage a backstop while the other workpiece is rotated against it or the workpiece 22 may be forced by an hydraulic ram against another workpiece rotated by a head fixed relatively to the slides. The rollers 102, 106 may be replaced by bushes having flat operative surfaces.