Patent ID: 6237700
Filing Date: 2001-05-29
Classification: B25D

Abstract:
A pneumatic-spring percussion mechanism for an impact hammer and/or drill hammer, havinga drive piston (1) which can be moved axially back and forth and has a guide sleeve (1a), a piston head (2) and a piston-suspension means (3);a percussion piston (17) which can be moved axially back and forth in the guide sleeve (1a); and havinga cavity (19) which is formed between the drive piston (1) and the percussion piston (17) and encloses a pneumatic spring; it being the case thatprovided in the guide sleeve (1a) is at least one air-equalizing slot (5) which is of a length which is greater than the axial length of a contact surface between the percussion piston (17) and the guide sleeve (1a);the guide sleeve (1a) is guided by a guide tube (16) which covers the air-equalizing slot (5) on its radially outer side; andthe cavity (19) can be brought into connection with a front end side (1b) of the drive piston (1) via the air-equalizing slot (5).