A technique for making a handle vibration-proof while avoiding size increase is provided in an impact tool. The impact tool has a striking mechanism part for driving a tool bit in its axial direction, a motor for driving the striking mechanism part, a tool body housing the motor and striking mechanism part, an outer shell housing covering part of the tool body, a handle that is integrally formed with the outer shell housing and extends transversely to the axial direction, a first handle end portion formed on one extending end of the handle, a second handle end portion formed on the other extending end of the handle, a first elastic element that connects the first handle end portion and tool body for relative movement in the axial direction, and a second elastic element that connects the second handle end portion and tool body for relative movement in the axial direction.

A hand-held power tool is disclosed. The tool has a tool receptacle for holding a chiseling tool. A pneumatic percussion mechanism of the hand-held power tool includes a striker, an exciter and a guide tube. The striker is designed to apply impacts in the impact direction to the tool. The exciter is motor-driven. The striker is coupled by an air spring to the reciprocating movement of the exciter. The striker abutting the guide tube is guided along a working axis. During a movement between an impact position and the exciter, the striker is guided with a constant guide length on the guide tube and if the impact position is exceeded in the impact direction, the guide length is reduced. The hand-held power tool is equipped with an inclined guide, which inclines the striker relative to the working axis when the impact position is exceeded.

A power tool, such as a rotary hammer or hammer drill, includes a first housing that contains a motor and a drive mechanism for linearly reciprocally driving a tool accessory, and a second housing that includes a handle, a first portion and a second portion. At least one elastic element connects the first and second housings such that the handle is biased away from the first housing. A first set of sliding contact surfaces is defined on or connected to the first housing and the first portion of the second housing. A second set of sliding contact surfaces is defined on or connected to the first housing and the second portion of the second housing. The first and second sets of sliding contact surfaces are located on opposite sides of the motor such that the rotational axis of the motor intersects the first and second sets of sliding contact surfaces.

Power tool, in particular a hammer drill, including a housing, a tool fitting for receiving and holding a tool, an impact device for producing and transmitting impact pulses to the tool, and a rotation device for producing and transmitting a torque to the tool, wherein a working axis passing through the impact device is provided. The power tool includes a first drive unit having a first axis of rotation for driving the rotation device and a second drive unit having a second axis of rotation for driving the impact device, wherein the first and second drive units are arranged in such a way relative to one another in the housing that the first axis of rotation of the first drive unit is arranged at a first angle to the second axis of rotation of the second drive unit and at a second angle to the working axis.

A rotary hammer tool can include a housing, a first motor supported by the housing, a spindle rotated by the first motor, a second motor supported by the housing, and a reciprocation mechanism reciprocated by the second motor. The reciprocation mechanism can include a piston driven to reciprocate within the spindle and a striker to reciprocate within the spindle in response to reciprocation of the piston. The rotational speed of the spindle and a reciprocation frequency of the reciprocation mechanism may be independently controllable.

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 hydraulic hammer is disclosed having a piston and an accumulator membrane disposed external and co-axial to the piston. Additionally, a sleeve is disposed between the piston and accumulator membrane, wherein the sleeve has a plurality of radial passages formed therein that fluidly connect the accumulator membrane with the piston.

An impact system for a hydraulic hammer is disclosed. The impact system may include a piston, a sleeve disposed co-axial with the piston, and an accumulator membrane disposed external to the sleeve. A first seal may be located at an end of the sleeve, and configured to connect the sleeve to the piston. The accumulator membrane may have an extension configured to engage a recess in the sleeve.

A hammer drill serving as an impact tool is provided with a crank housing that accommodates a crankshaft, and a cylinder accommodated in the crank housing. Receiving portions that receive the cylinder which is pressed rearward are provided at multiple locations of the crank housing in the front-rear direction. At least one of the receiving portions is disposed to receive the rear-end portion of the cylinder. A portion of the cylinder, which is received by another one of the receiving portions is a circlip (circumferential member) made of a metal.

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.