Provided is a reciprocating work machine capable of further reducing vibration transmitted from a housing to a handle. The reciprocating work machine provided with an electric motor, a piston and a striker reciprocating by power of the electric motor and striking a tool, and a housing accommodating the electric motor, the piston, and the striker, includes: a resin handle operably connected to the housing; a spring provided between the housing and the handle and expanding and contracting in a reciprocating direction of the piston and the striker when the handle operates relative to the housing; and a weight provided to the handle and made of a material having a specific gravity higher than each of a specific gravity of a material constituting the handle and a specific gravity of a material constituting the housing.

A hand-held power tool, in particular a demolition hammer, with an impact mechanism assembly includes an electric motor, an eccentric assembly, and an impact pin oscillating linearly along an impact mechanism axis. The eccentric assembly includes an eccentric wheel mounted in an impact mechanism carrier of the impact mechanism assembly, an eccentric wheel rotating about an eccentric axis, and a connecting rod driven by the eccentric wheel. The electric motor has a motor shaft along a motor axis which drives the impact piston by way of the eccentric wheel and the connecting rod. The eccentric wheel has an eccentric hub formed on one side, which is mounted along the eccentric axis on a side of the eccentric wheel facing away from the connecting rod proximally with a floating bearing and distally with a fixed bearing in the impact mechanism carrier.

A hand-power tool includes at least one oscillation-damping device that has at least one damping spring, a damping mass, and a mechanism housing. The oscillation-damping device has at least two retaining parts that at least partly enclose the damping mass.

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).

The representative impact tool has a motor, a driving mechanism, a body housing and a handle, and part of the motor and part of the handle are disposed on an axis of a tool accessory. The impact tool has an outer housing that is disposed to cover the outside of the body housing and connected to the body housing via an elastic element so as to be allowed to move with respect to the body housing in an axial direction of the tool accessory, and the handle is integrally connected to the outer housing. The body housing has an exposed region in which at least part of a region of the body housing corresponding to at least one of the motor and the driving mechanism, is not covered by the outer housing.

A hand-held power tool includes at least one transmission housing, at least one single-stage transmission unit, at least one motor housing, and at least one compensating unit. The at least one transmission unit is disposed in the at least one transmission housing. The at least one compensating unit includes at least one movably mounted compensating mass element. The at least one compensating unit is disposed at least for the most part in the at least one transmission housing or between the at least one transmission housing and the at least one motor housing.

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.

The disclosure provides a work tool having an electric motor, a power transmission means that receives motive power from the electric motor and transmits the motive power to a tip tool, a gear housing for accommodating at least a portion of the power transmission means, weights swingably supported on the gear housing, and coil springs that function as an urging means for urging the weights such that the weights are located at an initial neutral position, wherein the weights and the coil springs are provided respectively on the two sides of the gear housing so as to put the power transmission means therebetween, and a rotational support axle is provided that functions as a connecting means for connecting the weights provided on both sides of the gear housing so as to connect the weights such that the weights swing integrally.

A power tool includes a housing, a motor that is disposed within the housing and defining a first axis, and a tool holder driven to oscillate about a second axis by the motor. The second axis is perpendicular to the first axis. The power tool also includes a vibration dampening assembly with a counterweight that is configured to reciprocate along a third axis that is perpendicular to both the first axis and the second axis in response to oscillation of the tool holder about the second axis.

A hand-held power tool, in particular a demolition hammer, with an impact mechanism assembly includes an electric motor, an eccentric assembly, and an impact pin oscillating linearly along an impact mechanism axis. The eccentric assembly includes an eccentric wheel mounted in an impact mechanism carrier of the impact mechanism assembly, an eccentric wheel rotating about an eccentric axis, and a connecting rod driven by the eccentric wheel. The electric motor has a motor shaft along a motor axis which drives the impact piston by way of the eccentric wheel and the connecting rod. The eccentric wheel has an eccentric hub formed on one side, which is mounted along the eccentric axis on a side of the eccentric wheel facing away from the connecting rod proximally with a floating bearing and distally with a fixed bearing in the impact mechanism carrier.