WAGENHEBER

摘要

A lifting jack having a hollow upright column (10), a foot (12) at the bottom, and a threaded spindle (18) and a carriage (26) which extends through a longitudinal slit (22) in the upright column (10), is provided with a carrier arm (24) and a nut (30) movable on the threaded spindle (18). In order that, should the carrier arm (24) be overloaded, the upright column section is not deformed such that its longitudinal slit (22) undergoes an unacceptable widening, either the rear (10b) of the upright column (10) opposite the longitudinal slit (22) has an increased wall thickness, and/or on either side of the longitudinal slit (22) interengaging sections (26c) and (10e) are provided on the carriage (26) and the upright column (10) and come into effect only on such an overload and hook the edge regions of the upright column wall adjacent to the upright column longitudinal slit (22) onto the carriage (26) such that the longitudinal slit (22) cannot be widened by the overload. The interengaging sections may include a separate plastics strip (26e'') (Fig 4, not shown), engaging in grooves in the carriage and the column. <IMAGE>