A pneumatic impact tool having a vibration reducing structure includes a handle with a bucket member and a directional control valve. A tube member including a cylindrical wall and a chamber is coupled with the bucket member. The chamber is divided into a front and a rear chamber portion by a hammer member. Gas may be guided into the front or the rear chamber portion by the directional control valve. A vent is disposed on the cylindrical wall. An exhaust channel which communicates with the front chamber portion and not communicates with the rear chamber portion is disposed on an outer peripheral surface of the hammer member. The hammer member is pushed to return if gas is guided into the front chamber portion. Gas in the front chamber portion is exhausted when the exhaust channel communicates with the vent.

The invention relates to a pneumatically operated drill hammer, comprising a piston and a distributor axially arranged relative to each other in a housing, the piston being arranged to be moved axially between a first position and a second position. The drill hammer further includes a pneumatic drive system, including a drive chamber, a return chamber and a plurality of channels for distribution of drive gas in said drive system. The return chamber is arranged at a lower side of the piston and the drive chamber is arranged at an upper side of the piston, wherein the drive chamber is defined by a variable space enclosed by at least the housing, the piston and the distributor. The drive chamber includes at least one inlet port and at least one exhaust port arranged at a circumference of the drive chamber.

A vibration reducing structure of pneumatic hammer includes a handle having a concave room with a bottom wall and an air inlet channel communicating with the concave room. A control valve is disposed in the air inlet channel. A movable inner tube shell is accommodated in an outer tube shell coupled with the concave room and extends a rear bucket portion into the concave room. A movable hammer member, an air inlet valve for activating the hammer member and a hole communicating the air inlet channel to the air inlet valve are disposed in the inner tube shell. An air room is formed between the bottom wall and an end wall of the inner tube shell. A communicating channel communicates the air inlet channel to the air room for air with high pressure entering the air room.

An air impact tool includes an inner tubular member that is connected to the barrel. The inner tubular member has an annular wall and a cavity. The annular wall has exhaust hole. An air flow channel communicating with the air flow control valve and the cavity is defined inside the annular wall. The air flow channel is formed with a first air inlet. A hammer is in the cavity. The hammer is in close contact with the annular wall. A cylindrical gap is defined between a middle section of the hammer and the annular wall. The hammer has an exhaust passageway communicating with the cavity and the cylindrical gap. When the compressed air is injected into the cavity from the first air inlet, the hammer is pushed back, and the compressed air is exhausted via the exhaust passageway, the cylindrical gap and the exhaust hole in sequence.

A cushion device is used for a cylinder of a pneumatic tool, and the pneumatic tool contains: a body, a cylinder, a valve unit, a piston member, and a cushion washer. The body includes a grip and a fitting sleeve having a chamber, a closing face, and an opening. The cylinder is slidably fitted in the chamber, partially extends out of the fitting sleeve from the opening, and includes a room and an abutting portion. The valve unit is mounted between the room and the abutting portion. The piston member is accommodated in the room and slides along a movement axis. The cushion washer is made of a flexible rubber, is mounted in the chamber, and abuts against the closing face and the pressing face. The cushion washer includes at least one open segment which has at least one air groove each having a mouth parallel to the movement axis.

A method of regulating the disassembly of a component from a powered tool assembly that uses a pressurized fluid and a locking member that is in operative association or communication with the fluid is provided. The method comprises biasing the locking member into a locked configuration using the pressurized fluid, preventing movement of the component in a first predetermined direction.

The rotary percussive hydraulic perforator comprises a body; a fitting; a striking piston configured to strike the fitting; a stop piston including a front face facing the fitting and a rear face situated opposite to a rear wall of a cavity receiving the piston stop; and a main hydraulic supply circuit including a high pressure fluid supply conduit and a low pressure fluid return conduit. The body and the stop piston delimit a first control chamber permanently connected to the high pressure fluid supply conduit and configured to bias the stop piston forwards, and a second control chamber configured to bias the stop piston forwards and permanently connected to a low pressure accumulator connected to the low pressure fluid return conduit.

A vibration reducing structure of pneumatic hammer includes a handle having a concave room with a bottom wall and an air inlet channel communicating with the concave room. A control valve is disposed in the air inlet channel. A movable inner tube shell is accommodated in an outer tube shell coupled with the concave room and extends a rear bucket portion into the concave room. A movable hammer member, an air inlet valve for activating the hammer member and a hole communicating the air inlet channel to the air inlet valve are disposed in the inner tube shell. An air room is formed between the bottom wall and an end wall of the inner tube shell. A communicating channel communicates the air inlet channel to the air room for air with high pressure entering the air room.

Systems and methods for reducing vibration in power tool. One system includes a power tool that includes a housing and a motor. The power tool further includes a magnetically susceptible fluid located within the housing. The power tool further includes an inductor configured to introduce a magnetic field to the magnetically susceptible fluid. The power tool further includes a sensor configured to indicate an amount of vibration experienced by the power tool. The power tool further includes an electronic processor coupled to the sensor and to the inductor. The electronic processor is configured to receive a user-selected sensitivity level for vibration control, to receive an input signal from the sensor indicating the amount of vibration, to generate a control signal based on the input signal, and to provide the control signal to the inductor to control the magnetic field.

A vibration reducing structure of pneumatic hammer includes a handle having a concave room with a bottom wall and an air inlet channel communicating with the concave room. A control valve is disposed in the air inlet channel. A movable inner tube shell is accommodated in an outer tube shell coupled with the concave room and extends a rear bucket portion into the concave room. A movable hammer member, an air inlet valve for activating the hammer member and a hole communicating the air inlet channel to the air inlet valve are disposed in the inner tube shell. An air room is formed between the bottom wall and an end wall of the inner tube shell. A communicating channel communicates the air inlet channel to the air room for air with high pressure entering the air room.