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, a cushion washer, and at least one spring. The body includes a grip and a fitting sleeve having a chamber, a closing element, and an opening. The cylinder is fitted in the chamber 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 and the at least one spring are mounted in the chamber, and the cushion washer abuts against the closing element 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 lubrication system including a drive fluid chamber and a lubricant chamber. A first movable member is movable from a first position to a second position within the drive fluid chamber in response to drive fluid pressure acting on the first movable member. A second movable member is movable between a first position and a second position within the lubricant chamber and is operatively coupled to the first movable member. A biasing member is positioned to bias the first movable member toward the first position. A relief valve is associated with the first movable member and, when the relief valve in an open state, the drive fluid pressure acting on the first movable member is reduced such that the biasing member moves the first movable member to the first position within the drive fluid chamber.

A claw hammer includes a circular or oval recessed hole located on one lateral wall of a hammerhead thereof, a circular through hole located in a bottom wall of the recessed hole and cut through the other lateral wall of the hammerhead, a V-shaped opening extended from the border of the through hole and defining two abutment edges. When extracting a nail laterally, move the hammerhead horizontally to receive the head of the nail in the through hole and to abut the two abutment edges of the V-shaped opening against the shank of the nail, and then bias the handle of the claw hammer to extract the nail. Thus, the claw hammer provides an added lateral nail extracting function.

A hammer tool for hammering on a workpiece by a tool bit moving at least linearly in a longitudinal direction of the tool bit, configured so that a hammering element moves toward the tool bit to hits the tool bit by way of air pressure fluctuation in an air chamber when a driving element is moved from a first position to a second position. In addition, the stroke center position of the reciprocating movement of the driving element moved between the first position and the second position is configured to be changeable.

An electrical hammer (100) comprises a main housing (101), a hand grip (500) connected to the main housing (101) via a compression coil spring (321). In the electrical hammer (100), a hammer bit (119) is driven by a first motion converting mechanism (120) and thereby a hammering operation is performed. During the hammering operation, the hand grip (500) is moved against the main housing (101) in a state that biasing force of the compression coil spring (321) is applied on the hand grip (500). Further, the electrical hammer (100) comprises a second motion converting mechanism (220) which drives a counterweight (231).

A breaking device includes a frame, an impact device having a pressure chamber with a rear pressure chamber and a front pressure chamber. The breaking device further includes a first low pressure port at the rear pressure chamber, a first low pressure channel and a first low pressure accumulator connected to the first low pressure channel. The breaking device further includes a second low pressure port at the rear pressure chamber substantially opposite to the first low pressure port, second low pressure channel and a second low pressure accumulator connected to the second low pressure channel. The first low pressure accumulator and the second low pressure accumulator are arranged at the outer circumference of the frame of the breaking device at different positions in the axial direction of the breaking device.

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, a cushion washer, and at least one spring. The body includes a grip and a fitting sleeve having a chamber, a closing element, and an opening. The cylinder is fitted in the chamber 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 and the at least one spring are mounted in the chamber, and the cushion washer abuts against the closing element 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.

The invention relates to an impact machine which is adapted to perform a hammering operation on a surface or an object to be worked upon. In particular, a vibration reduction arrangement is attached to the housing and comprises a moveable counterweight, interacting with a motion reversing arrangement having a non-linear spring characteristics, such that the motion of the counterweight can be brought into a counter-acting movement in relation to the vibrations in the housing of the hammering element thus substantially reducing the vibrations. A spring action arrangement is arranged inside said counter weight, the counter weight being movable a first distance without actuating the spring action arrangement, and the counterweight comprises displaceable projecting member for actuating the spring action arrangement.

A hammer assembly used in a machine is described. The hammer assembly comprises a power member, a tool member, and a housing member. The housing member includes a first set of channels and a second set of channels. The first set of channels is disposed along a first axis and the second set of channels is disposed along a second axis in an orthogonal direction with respect to the first axis. The hammer assembly is rotated by an angle to make use of any one of the first set of channels or the second set of channels. The first set of channels is shaped to receive a first set of pins and the second set of channels is shaped to receive a second set of pins for engagement of the housing member and the tool member.