Abstract: A mechanism is described for incorporating into a clamping workbench of the type comprising a pair of main clamping jaws (234, 237) and a supplementary clamping jaw (230) which is movable as a consequence of relative movement of the main jaws to engage and clamp a workpiece lying across the main jaws. The clamping movement of the supplementary jaw (230) is generally perpendicular to that of the main jaws. The invention concerns a supplementary jaw (230) having a single actuating arm (238), one end of which is adapted to be pivotally received in an opening (246) in one of the main jaws (237), and the other end of which is slidably connected to the supplementary jaw (230) and held captive therein by pin means (304, 306) extending above and below the captive end of the arm (238).

Abstract: Supplementary jaw means is described for fitting to a clamping workbench transversely to the main jaws thereof at a position spaced from stop means at the other end of the main jaws, whereby operation of the drive means which moves the main jaws towards or away from each other will increase the distance between the supplementary jaw means and the stop means when operated in one sense, and will decrease the distance therebetween when operated in the other sense. A clamping workbench may be fitted with one supplementary clamping jaw means and a fixed stop for clamping a workpiece therebetween above the main clamping jaws.