Patent ID: 7891227
Filing Date: 2011-02-22
Classification: B21D,B25J

Abstract:
1. A gripping apparatus for gripping and holding elongated workpieces, in particular for bending machines, said apparatus comprising: a guiding body and an axially consecutive housing located on a common longitudinal axis, the housing, carrying two gripping jaws, each of said gripping jaws being pivotable about an axis of rotation and movable between an opened receiving position and a closed clamping position, the guiding body having an axial end surface facing the housing and guidingly supports the housing such that the housing is displaceable with respect to the guiding body axially in an extension direction over a predetermined maximum travel distance from a retracted initial position, in which the housing is in only axial contact with said axial end surface of the guiding body, to an end position, in which the housing is the predetermined maximum travel distance axially away from said axial end surface of the guiding body, wherein the gripping jaws are mounted to an end region of the housing opposite from the guiding body, the gripping apparatus further comprising a control element attached to an end of a rod, the control element movable relative to the housing and to the gripping jaws, the rod is movable within the guiding body, said control element comprising a control surface, which is located in a plane of intersection perpendicular to the axes of rotation of the gripping jaws and comprising the longitudinal axis, said control surface being symmetrical to the longitudinal axis and tapering away from the rod in the extension direction, with the central axis of the control element being centrally located between both gripping jaws, and the control element being displaceable between an extended end position, in which it spreads apart the two gripping jaws' end regions facing it, so as to assume the clamping position of the gripping jaws, and a retracted end position, in which the end regions of the gripping jaws converge so as to assume their opened receiving position, and the control element, in its retracted end position, abutting against a stop in the housing, wherein the housing being constantly spring-biased in a direction away from said axial end surface of the guiding body towards the extended end position of the housing by a compression spring provided between the guiding body and the housing, and the control element, having reached its retracted end position upon being retracted, takes the housing along in a further retraction movement, against the spring bias of the latter relative to the guiding body until the housing contacts the guiding body.