Hydraulic Swivel Drive And Grab With Such Swivel Drive

摘要

A hydraulic swivel drive for a grab that has two gripping arms or shells movable like tongs, including two swivel shafts parallel to each other and rotatably mounted in a drive housing, whose shaft ends are connectable with the gripper arms or shells, wherein the swivel shafts each have two oppositely threaded screw engagement portions, with which two pistons movable in opposite directions by means of hydraulic pressure for driving the swivel shafts are in screw engagement. Two differently large and differently contoured cylinder pressure chambers can be assigned to each piston in order to optimally adapt the cross-sectional area of the pistons for each of the reciprocating positioning movements and to appropriately select the pressure conditions. To be able to run in the differently contoured and dimensioned cylinder pressure chambers, each of the pistons is provided with different piston portions which are adapted to the respective cylinder pressure chamber.

主权项

1. A hydraulic swivel drive for a grab that has two gripping arms or shells movable like tongs, comprising two swivel shafts rotatably mounted in a drive housing and parallel to each other, whose shaft ends are connectable with the gripping arms, wherein the swivel shafts each have two oppositely threaded screw engagement portions, with which two pistons movable in opposite directions for driving the swivel shafts are in screw engagement, wherein the pistons each have two piston running surfaces on the outer shell surface, which are shaped differently in cross-section and are arranged to run in differently large cylinder pressure chambers shaped differently in cross-section, which are formed by the drive housing.