Percussion mechanism for an electrical hand-held tool with a blank blow cut-off

US6467555B2 · kind B2 · utility

Assignee

• Hilti Aktiengesellschaft · LI

Inventors

• Uto Plank · Freising, DE
• Martin Richter · Stuttgart, DE

Key dates

• Filing date: Jan 23, 2002
• Grant date: Oct 22, 2002
• Expiry date: Jan 23, 2022

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B25D2250/035
• WIPO field: Machine tools
• WIPO sector: Mechanical engineering

Abstract

A percussion mechanism for an electrical hand-held power tool including a guide tube, a percussion piston (4) axially displaceable in the guide tube (2), an anvil (5) for impacting a working tool and axially displaceable together with the percussion piston (4), a gas spring (1) provided on an axial side of the percussion piston (4) remote from the anvil (5), an air channel (9) for aeration of the gas spring (1) and extending between an axial region of the gas spring (1) and an axial region of the anvil (5) outwardly of the inner surface of the guide tube (2), and a ventilation opening (8) for communicating the air channel (9) with a surrounding environment and which is closed by the anvil (5) in its operational position.