Patent ID: 6959967

Claim:
A fluid-powered impact vibrator comprising: a fluid-powered percussion hammer having a percussion piston that can be moved back and forth within a cylinder housing by controlled fluid pressure, and a guide unit on which the percussion hammer is supported; control means, connected between a fluid pressure inlet line and a pressure inlet to the cylinder housing, for controlling the back and forth movement of said percussion piston, with the control means including a valve moveable between operating stroke and return stroke positions for the percussion piston; and a control valve which is a component of one of the guide unit and the percussion hammer itself, and which is one of a pressure shut-off valve and a pressure-limiting valve, connected to the pressure inlet line for monitoring the fluid pressure in the pressure inlet line, and connected to the control means for causing the percussion hammer to be stopped automatically by at least one of blocking the pressure inlet line and holding the control means in one of its operating stroke and return stroke positions if the operating pressure in the fluid pressure inlet line exceeds a specified maximum value.