Hammering Apparatus

Abstract

Hammering apparatus functioning with a pressurized medium, such as a pressure fluid of a hydraulic system which hammering apparatus comprises an elongated body (19) to be attached to a power tool, a movable impact mass (10) adjusted to rest on the body (19) for which impact mass a linear control part is adjusted to the mentioned body (19) and an arrangement for lifting up the movable mass (10) for the impact comprising the first cylinder (20) and a piston (16) which can be moved in it with the help of pressure fluid and a piston rod (1) in which case in the arrangement the mentioned piston rod (1) is attached to the mentioned mass (10) and comprises a valve arrangement (15) with the help of which the pressure of the hydraulic fluid can be directed to the first cylinder (20) to the other side of the piston (16) for the uplifting of the mass (10) and the mentioned pressure can be suddenly reduced when the mass (10) is being directed to impact. During the impact of the mass (10) the hydraulic fluid or a part of it coming back from the cylinder space (6) of the first cylinder (20) can be directed to an expanding space (2) inside the piston rod (1) with the help of a valve arrangement (15) in which case a harmful back pressure caused by the hydraulic fluid being removed from the front of the piston (16) is essentially reduced.

Dependencies are inferred from the claim text.