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.

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 shock absorption structure of a pneumatic tool, the pneumatic tool contains: a body, a cylinder, a gas valve unit, an impact element, and an elastic unit. The body includes an air channel and a cavity having a closing face, an opening, and an air chamber. The body also includes a first orifice and a second orifice. The cylinder includes a sliding room, a contacting fringe, a defining cutout, and an air inlet. The gas valve unit is fixed between the sliding room and the contacting fringe. The impact element is disposed in the sliding room and is pushed by the high pressure gas to reciprocately move. The elastic unit includes an elastic pushing force and is secured in the air chamber so as to push against the closing face and the contacting fringe and to push the cylinder to move away from the grip handle.

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 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.

In an improved air inlet valve assembly, a flow of air along a first or second flow path may be controlled by a position of air inlet guide surfaces of a rotatable valve relative to air inlet guide slots of a fixed valve sleeve. Air flowing along the first flow path may rotate a motor in a first direction to operate the tool in a forward mode. Air flowing along the second flow path may rotate the motor in the second direction to operate the tool in a reverse mode. In the forward mode, as air flows along the first flow path, air may be discharged along a primary discharge path, with a portion of the second flow path providing a secondary discharge path. In the reverse mode, as air flows along the second flow path, air may be discharged along the primary discharge path, with a portion of the first flow path providing the secondary discharge path.

In an improved air inlet valve assembly, a flow of air along a first or second flow path may be controlled by a position of air inlet guide surfaces of a rotatable valve relative to air inlet guide slots of a fixed valve sleeve. Air flowing along the first flow path may rotate a motor in a first direction to operate the tool in a forward mode. Air flowing along the second flow path may rotate the motor in the second direction to operate the tool in a reverse mode. In the forward mode, as air flows along the first flow path, air may be discharged along a primary discharge path, with a portion of the second flow path providing a secondary discharge path. In the reverse mode, as air flows along the second flow path, air may be discharged along the primary discharge path, with a portion of the first flow path providing the secondary discharge path.

A driving tool includes a first piston slidably disposed within a cylinder chamber and having an elongated driving part configured to drive a struck material. A second piston is configured to generate compressed air within the combustion chamber. A compressed air supply passage enables communication between the compression chamber and the cylinder chamber. A valve member opens and closes the compressed air supply passage. A relay member mechanically connects an electric motor with the valve member. The valve member opens and closes the compressed air supply passage via the relay member.

A pneumatic tool with changeable exhaust direction includes a tool main body and a direction change assembly. The tool main body includes a housing portion having a first exhaust channel. The direction change assembly includes an air guidance member and an adjustment member. The air guidance member is mounted onto the housing portion, and a second exhaust channel is formed with the air guidance member. The adjustment member is installed with a sealing ring. The adjustment member generates an axial movement relative to the air guidance member and along a first axis to move away from the air guidance member in order to open the second exhaust channel or to allow the sealing member to abut against the air guidance member in order to close the second exhaust channel. Accordingly, the exhaust direction is adjustable during the use of the pneumatic tool in order to facilitate different processing operations.

A prior art powered wrist pin knocker is improved with a new plunger that prevents wobbling. The new plunger responds to a return vacuum pressure. The improved plunger is symmetrical along a longitudinal axis. New embodiments include a new side mount valve head to reduce length, a remote air controller and a variable length cylinder for the cannon. The new valve head is a simplified valve head assembly that adapts to an end of the cannon mount or a side mount or a remote mount. Another embodiment provides a stand for a surface mount application. This embodiment can have an extended piston for loosening tail bearings down a long channel. A manual return embodiment can use a rod to manually return the plunger to the proximal end for another firing cycle.