Patent ID: 9701002
Date: 2017-07-11
CPC Classifications: B25D,E02D

Claim:
1. A hammering device which can be attached to a working machine, the hammering device comprising: a body, a moving hammering piston inside the body, a hammering element, a gas filled chamber space at a first side of the hammering piston, a first ring-shaped chamber space around the hammering piston, a second ring-shaped chamber space around the hammering piston and axially in line with the first ring-shaped chamber space and a ring-shaped valve between the first ring-shaped chamber space and the second ring-shaped chamber space, the valve comprising a group of holes, whereby feeding pressure fluid to the first ring-shaped chamber space moves the hammering piston to a hammering position the hammering piston thereby compressing gas in the gas filled chamber space, thereafter blocking the feeding of the pressure fluid to the first ring-shaped chamber space and opening the valve allows the pressure fluid to flow from the first ring-shaped chamber space to the second ring-shaped chamber space thereby causing the hammering piston to perform a hammering movement to the hammering element and the movement of the hammering piston being arranged to change volumes of the first and second ring-shaped chamber spaces.