Hydraulic screw tightening or tensioning device

US7661336B2 · kind B2 · utility

Inventors

• Jörg Hohmann · Meschede, DE
• Frank Hohmann · Warstein, DE

Key dates

• Filing date: Aug 4, 2005
• Grant date: Feb 16, 2010
• Expiry date: Aug 4, 2025

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B25B29/02
• WIPO field: Machine tools
• WIPO sector: Mechanical engineering

Abstract

A hydraulic screw tensioning device includes a cylinder supported on a machine part that is to be clamped by a threaded bolt and nut. A first annular piston is guided in a sealed manner in a cylinder element, is disposed on the change sleeve, and is supported against an inclined surface of a monolithic collar of the change sleeve. At least one second annular piston is guided in a sealed manner in a cylinder element, is disposed on the change sleeve, and is supported against the first annular piston. Respective, facing inclined axial annular surfaces on the annular pistons and on the cylinder elements or annular shoulders thereof are inclined in the same direction and are pressure-remote. Annular surfaces on the second annular piston or pistons and on the annular shoulders of the cylinder elements extend perpendicular to the cylinder axis and are pressurized.