GB1096459A - Cramping device - Google Patents

Abstract

1,096,459. Vice. F. ARNOLD. April 6, 1965 [April 7, 1964], No. 14632/65. Heading B3B. [Also in Division F2] A toggle mechanism providing high clamping pressures a machine vice 1, comprises two opposed toggle levers, each consisting of three rollers 11, 12, 13 and two struts 15, 16 having semicylindrical recesses (14) (Fig. 3, not shown) each end in which the rollers are supported, which are arranged between an abutment 9, of a U-shaped carrier, and a movable jaw 3, the toggles being brought into action when, after the workpiece is initially gripped between the movable jaw 3 and a fixed jaw 2 by rotating a quick-acting screwed spindle 7, further operation of the spindle causes a large roller 18, fast on a centre rod 10 of the spindle 7, to be axially thrust between and force apart the centre rollers 12 of the toggles. The clamping pressures may be varied by an adjustable stop 24 which has varying height stop faces 25, 26 limiting the movement of the rod 10. The hollow spindle 7 is rotated in a nut 5, bolted at (6) (Fig. 1, not shown) in one of a number of positions along the vice 1 to suit varying workpiece widths, by a handle 8 through a spindle 43 and an overload release coupling formed on the spindle 43 by a disc 46 having a facial wedge shaped tongue 48 spring biased at 47 into a corresponding slot in a nut 44 secured by pins 45 to the spindle 7, the end of the spindle 43 bearing on the outer end of the centre rod 10 such that in operation, rotation of the spindle unit moves the vice jaw 3 into contact with the workpiece and further rotation of the handle 8 releases the outer spindle 7 and nut 44 from spindle 43 which then thrusts through the rod 10 to operate the toggle mechanism. The abutment 9 carries spring loaded bolts 37 whch co-operate with stops 35 in the slide 4 to pre-load the toggles into contact with the centre thrust roller 18.