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 carbon-fiber seat for a pneumatic hammer has a rear valve, a front valve, and a valve plate. The rear valve, the front valve, and the valve plate are made of carbon fiber materials. The rear valve has an inlet recess, an inlet passage, an exhaust annular recess, at least one exhaust port, and at least one exhaust passage. The front valve abuts the rear valve and has a communicating recess, an exhaust mount, and at least one exhaust port. The communicating recess is formed through the front valve, and communicates with the inlet recess of the rear valve. The exhaust mount is formed on and protrudes axially from the front valve around the communicating recess. The at least one exhaust port is formed in the exhaust mount such that the communicating recess communicates with the outer recess. The valve plate is deposited between the two valves.

An eccentric drive 1 for a portable power tool 2 has a motor 5, an eccentric wheel 6, a linear guide 9, a slide 8 and a connecting rod 7, which has a head 17 suspended on the slide 8 and a second head 15 suspended on the eccentric wheel 6. A bearing bush 16 for the rotatable mounting of the connecting rod 7 is provided at least on one of the two heads 17. The head 15 is composed of an injection molding material. The bearing bush 16 is composed of a fiber composite material, which includes continuous carbon fibers 25 embedded in a thermoplastic matrix.

A power tool is disclosed. The power tool has a pneumatic percussion mechanism with a percussion element guided on a working axis and a percussion surface pointing in a percussion direction, an exciter piston driven by a motor, and a pneumatic chamber formed between the exciter piston and the percussion element. The percussion element has a first partial body forming the percussion surface, a second partial body, and a spring element. The first partial body is moveable along the working axis relative to the second partial body. The second partial body has an abutment surface pointing in the percussion direction. The first partial body has an impact surface opposite the abutment surface. The spring element drives the first partial body relative to the second partial body in the percussion direction into a starting position in which the abutment surface is separated from the impact surface by a gap.

A device absorbs shock in a pneumatic tool containing a body, a cylinder, a valve unit, a piston member, plural buffer springs, and multiple fitting sleeves. The body includes a grip and a fitting sleeve fitted with the grip. The fitting sleeve has a chamber, a close face formed on a first end thereof, and an opening formed on a second end thereof. Each fitting sleeve is hollow and includes a limitation length forming along a hollow extending direction and shorter than a largest length. Multiple positioning sleeves are defined between a close face of the fitting sleeve and an abutting portion of the cylinder, and the multiple positioning sleeves are hollow so as to accommodate plural buffer springs. Because the limitation length is shorter than the largest length, the plural buffer springs extend out of the multiple positioning sleeves respectively.

A powered fastener driver includes a housing defining a cylinder support portion and a motor housing portion, a cylinder within the cylinder support portion, and a piston movable within the cylinder. The piston is moveable from a top-dead-center (TDC) position to a bottom-dead-center (BDC) position along a driving axis. A stroke length is measured between the TDC position and the BDC position along the driving axis. The fastener driver also includes a driver blade attached to the piston for movement along the driving axis from the TDC position toward the BDC position for driving a fastener into a workpiece. The fastener driver includes a lifter operable to move the piston and driver blade, in unison, from the BDC position toward the TDC position. The piston includes a first seal and a second seal located at a distance of at least the stroke length from the first seal.

A power tool includes an air spring cylinder. A piston is movably positioned within the cylinder. A head valve assembly of the power tool includes a flapper valve configured to seal the air spring cylinder from an air accumulator when the flapper valve is in a non-firing position.

An improved pneumatically operated percussive tool and implement with a host of innovative design features that provide improved performance, drastically reduced weight, and speed of implement attachment and removal.

Disclosed is a device including an exhaust valve, that operates on a pressurised working fluid. The device includes a working chamber, defined at least in part by a side wall, which working chamber can hold a workload to or toward a first end thereof, the working chamber to receive the working fluid to act on a rear surface of the workload to propel the workload to or towards a second end, opposite the first, of the working chamber. The device also includes a return chamber to receive fluid under pressure from a front surface of the workload, the pressure developed at least in part by the movement of the workload towards the second end. Present also is an exhaust valve fluidly connected to the return chamber, the exhaust valve normally biased closed preventing working fluid from exiting the working chamber, but on receipt of, and action by, the fluid under pressure from the return chamber, will open to allow the working fluid to exhaust the working chamber to a lower pressure location, the working fluid exhausting via the side wall of the working chamber through to the exhaust valve. Provided then is a device that will remove or reduce pressure building on the rear surface of the workload when moved from the second end to the first end.

An actuation trigger for a device, comprising or including, A dose chamber to hold a charge of high pressure working fluid, received from a high pressure source, A dose valve, biased closed to seal the dose chamber off from a working chamber, and hold the charge in the dose chamber, A hammer operated by a piston with a driven chamber on a first side of the piston, and a trigger chamber on a second side of the piston, sealed from the first side, the driven chamber receiving high pressure working fluid directly or indirectly from the high pressure source, A trigger valve to selectively supply high pressure working fluid to the trigger chamber, or to release high pressure working fluid from the trigger chamber, Such that when the hammer has high pressure working fluid in both the driven chamber and the trigger chamber it is held by a force imbalance in a first position, and when the high pressure working fluid is released from the trigger chamber, the hammer is driven to, or towards a second position towards the trigger chamber, The hammer, when driven to, or towards the second position strikes the dose valve, unseating the dose valve to unseal the dose chamber and the working chamber thus allowing the charge to enter the working chamber to do work therein.