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 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.

Disclosed is a fluid hammer tool with two separate fluid hammers in separate sections of the tool. The tool includes an upper poppet valve assembly along one fluid flow path, and a lower poppet valve assembly along a separate outer flow path. Both fluid flow paths are fed from an upper sub and both exit through a lower sub. Both poppet valves include spring return mechanisms. Sealing of each poppet valve propagates an upstream shock wave. The lower poppet valve assembly encounters greater fluid flow and generates a larger shock wave. In the period when the upper poppet valve is closed, the lower poppet valve cannot open.

A system includes first and second power tools that each have a percussion mechanism, a motor, and a transmission. The transmission includes a striking mechanism and is configured to transfer a driving motion of the motor to an insert tool held in a tool holder. The transmission has a guide tube that is identical in some regions along a working axis and accommodates a striker. The guide tube is rotatably coupled to the motor by a first transmission unit. The striker is driven to linearly oscillate by a piston of a second transmission unit. A ratio between a diameter of the tool holder and a diameter of the guide tube is 1.8 times greater in the first power tool than in the second power tool. A striking energy of the second power tool is mechanically reduced compared to a striking energy of the first power tool.

A first required flow rate is calculated as a function of a first maximum allowable flow rate and a value of a first signal. A second required flow rate is calculated as a function of a value of the second signal. When the first maximum allowable flow rate is higher than a first capacity, the value of the first signal is a maximum level, and the value of the second signal is equal to or higher than a minimum level and equal to or lower than a maximum level, a first working fluid supply is controlled to discharge working fluid at a flow rate equal to the first capacity, and a second working fluid supply is controlled to discharge working fluid at a flow rate obtained by deducting the first capacity from the first maximum allowable flow rate, added to the second required flow rate.

A system includes first and second power tools that each have a percussion mechanism, a motor, and a transmission. The transmission includes a striking mechanism and is configured to transfer a driving motion of the motor to an insert tool held in a tool holder. The transmission has a guide tube that is identical in some regions along a working axis and accommodates a striker. The guide tube is rotatably coupled to the motor by a first transmission unit. The striker is driven to linearly oscillate by a piston of a second transmission unit. A ratio between a diameter of the tool holder and a diameter of the guide tube is 1.8 times greater in the first power tool than in the second power tool. A striking energy of the second power tool is mechanically reduced compared to a striking energy of the first power tool.

A first required flow rate is calculated as a function of a first maximum allowable flow rate and a value of a first signal. A second required flow rate is calculated as a function of a value of the second signal. When the first maximum allowable flow rate is higher than a first capacity, the value of the first signal is a maximum level, and the value of the second signal is equal to or higher than a minimum level and equal to or lower than a maximum level, a first working fluid supply is controlled to discharge working fluid at a flow rate equal to the first capacity, and a second working fluid supply is controlled to discharge working fluid at a flow rate obtained by deducting the first capacity from the first maximum allowable flow rate, added to the second required flow rate.

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 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.

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.