A hydraulic breaker provided with an automatic lubricant supply structure is proposed. The automatic lubricant supply structure is configured to automatically supply a lubricant without a separate hose, using a working fluid, and is disposed in the body of the hydraulic breaker, and can be used without a separate external part.

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 heatsink structure for a pile driver includes a rotation seat, a pivot base, a pile driver gear unit, and at least one radiating pipe. The rotation seat is pivotally connected with the pivot base. The pile driver gear unit is mounted in the pivot base and includes a receiving space and a vibration device. A pump device is mounted in the receiving space of the pile driver gear unit. The at least one radiating pipe is mounted on the pivot base. Thus, the lubricating oil in the receiving space of the pile driver gear unit is pumped by the pump device during operation and is delivered to the at least one radiating pipe so that the at least one radiating pipe cools down and carries away the heat of the lubricating oil.

A power tool includes a housing having a motor housing portion and a front casing coupled to the motor housing portion. The power tool also includes an electric motor positioned within the motor housing portion, a drive assembly having an output shaft to which a tool element for performing work on a workpiece is attachable, and a powdered metal bushing disposed within the front casing that rotatably supports the output shaft.

A lubrication system for a hydraulic hammer includes a body defining a recess in fluid communication with a lubricant inlet and a lubricant outlet. A sleeve, located co-axially within the recess, defines a stepped tubular cavity having first and second portions. The sleeve also defines inlet and outlet ports extending from an outer surface to an inner surface of the sleeve. A piston, located partly within the recess and the first portion of the stepped tubular cavity respectively, has a tubular cavity co-axial with the stepped tubular cavity. A spool is located partly within the tubular cavity and the second portion of the stepped tubular cavity respectively. The spool co-operates with the inlet and outlet ports of the sleeve for reciprocally moving the piston in relation to the body so that lubricant from the lubricant inlet is delivered by the piston to the lubricant outlet via the recess.

A tool bushing of a breaking hammer, a tool bushing arrangement, a breaking hammer and a method of mounting a tool bushing of a breaking hammer are disclosed. The tool bushing is a sleeve-like piece having a multi-shouldered outer surface with three or more successive cylindrical portions. The cylindrical portions have different diameters that match with corresponding surfaces of a bushing housing when the tool bushing is mounted. Diameters of the bushing and the bushing housing are dimensioned so that friction forces are generated when the bushing is assembled.

A spray dust compression system and method includes a nozzle holder for affixing a spray nozzle to a percussive tool. The nozzle holder includes an arcuate wall having a first surface engageable with the percussive tool, and a second surface opposing the first surface. A protruding body protrudes radially outwardly from the second surface relative to a longitudinal axis of the arcuate wall and a concave recess is formed in the protruding body and receives the spray nozzle. The concave recess is angled inwardly toward the longitudinal axis of the arcuate wall.

A tool includes a housing, a drive assembly including an output shaft extending from the housing such that a tool element for performing work on a workpiece is attachable to the output shaft, and a bushing disposed within the housing. The bushing rotatably supports the output shaft. The bushing is impregnated with lubricant such that the bushing is self-lubricating, and the bushing has an impregnation ratio between about 5% and about 25%.

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 hammer drill is provided including a housing, a motor mounted within the housing, and a hammer mechanism. The hammer mechanism includes a crank plate or a wobble plate driven by the motor, a con rod coupled to the crank plate or the wobble plate, a piston reciprocatingly driven by the con rod along a longitudinal axis, a ram and a beat piece. At least one of the wobble plate or the con rod is made of sintered steel.