Patent ID: 8240394

Claim:
A power-driven hammer comprising: a body including a tubular housing; and a barrel assembly received in the housing having an at-rest position relative to the housing when the hammer is not operating, the barrel assembly comprising: a barrel having a forward end adapted to hold a tool, an opening, and a rearward end opposite the forward end; and a mass received in the opening of the barrel, the mass moving in the barrel opening when the hammer is operating through a power stroke, in which the mass moves toward the forward end of the barrel to strike the tool when held in the barrel, and a return stroke, in which the mass moves toward the rearward end of the barrel; the barrel assembly moving forward and rearward from its at-rest position relative to the housing when the hammer is operating; and a vibration reducing mechanism connecting the barrel assembly to the body reducing shock transmitted to the housing as the mass moves forward and rearward in the barrel; wherein the vibration reducing mechanism comprises a first reduction member configured to decelerate forward movement of the barrel assembly relative to the body and a second reduction member configured to decelerate rearward movement of the barrel assembly relative to the body, wherein the first reduction member comprises a first spring, and wherein the second reducing member comprises a second spring, and wherein the vibration reducing mechanism comprises a fastener secured to a rearward end of the barrel assembly and extending through an opening in the housing, said first spring being held by the fastener outside the housing and said second spring is held by the fastener inside the housing.