A hydraulic, pneumatic, gasoline, diesel, or electric tool may include a spindle that is adapted for rotational movement. A swing arm may be coupled to the spindle such that rotational motion of the spindle is transferred to the swing arm. The swing arm makes contact with a piston such that the rotational motion causes the piston to move along a linear path. The piston may interact with an energy storage medium when the swing arm moves the piston in the first direction, causing energy to be stored in the energy storage medium. As the swing arm continues to rotate, the swing arm may lose contact with the piston, thus allowing the energy storage medium to urge the piston in a second direction opposite the first direction to strike an anvil. The swing arm may be a multiple roller swing arm. The energy storage medium may be a compound spring assembly.

A driver capable of suppressing increase in a load torque of a motor when a striking mechanism is moved by the torque of the motor against a force of a first moving mechanism is provided. The driver includes a striking mechanism 12 movable in a first direction B1 and a second direction B2 opposite to the first direction B1 and a first moving mechanism configured to move the striking mechanism 12 in the first direction B1 to strike a fastener, and the driver further includes a motor, a second moving mechanism 45 rotated by the torque of the motor and configured to move the striking mechanism 12 in the second direction against a force of the first moving mechanism, and torque suppression mechanisms 45A to 45H configured to suppress increase in the torque of the motor when the striking mechanism 12 is moved in the second direction B2.

A driver capable of suppressing increase in a load torque of a motor when a striking mechanism is moved by the torque of the motor against a force of a first moving mechanism is provided. The driver includes a striking mechanism 12 movable in a first direction B1 and a second direction B2 opposite to the first direction B1 and a first moving mechanism configured to move the striking mechanism 12 in the first direction B1 to strike a fastener, and the driver further includes a motor, a second moving mechanism 45 rotated by the torque of the motor and configured to move the striking mechanism 12 in the second direction against a force of the first moving mechanism, and torque suppression mechanisms 45A to 45H configured to suppress increase in the torque of the motor when the striking mechanism 12 is moved in the second direction B2.

A driving tool includes a piston, a driver, and a lift mechanism. The piston moves in a driving direction by a pressure of a gas. The driver extends from the piston and includes a plurality of engaged portions. The lift mechanism moves the driver in a direction opposite to the driving direction. The lift mechanism includes a rotation shaft, a wheel, a plurality of engaging portions, and a supporting member. The wheel rotates integrally with the rotation shaft. Each of the plurality of engaging portions may engage an engaged portion. The supporting member supports the wheel so the wheel is allowed to move between an initial position and an eccentric position in a radial direction of the rotation shaft.

A driving tool includes a piston, a driver, and a lift mechanism. The piston moves in a driving direction by a pressure of a gas. The driver extends from the piston and includes a plurality of engaged portions. The lift mechanism moves the driver in a direction opposite to the driving direction. The lift mechanism includes a rotation shaft, a wheel, a plurality of engaging portions, and a supporting member. The wheel rotates integrally with the rotation shaft. Each of the plurality of engaging portions may engage an engaged portion. The supporting member supports the wheel so the wheel is allowed to move between an initial position and an eccentric position in a radial direction of the rotation shaft.

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.

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.

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.