An impact tool includes a mechanism part, a main-body housing and a grip housing. The mechanism part strikes a tool bit. The main-body housing holds the mechanism part therein. The grip housing is continuously provided to a rear portion of the main-body housing. One end portion of the grip housing is displaceably connected to the main-body housing through an elastic member, and the other end portion of the grip housing is rotatably connected to the main-body housing through a rotary joint. A center of the rotary joint is disposed on a leading end side of the impact tool with respect to a center of the elastic member, when viewed in a strike direction of the impact tool.

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 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.

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.

An objective is to provide a technique to securely protect the striking tool even when the striking tool inadvertently falls down. A striking tool including a rotating shaft relatively rotatably connect a main body with a handle, a first elastic member reducing transmitting of vibration from the main body to the handle in a case that the handle relatively rotates to the main body, wherein the handle includes a battery mounting portion to which battery to drive the motor is attachable and the handle is arranged to relatively move to the main body across the rotating shaft, and an adjuster such that the relative movement amount of the handle to the main body in a predetermined direction is adjusted to be larger than the relative movement amount in a direction other than the predetermined direction.

A percussion tool includes a housing having a top end, a bottom end, a front end, and a rear end. The housing defines a barrel portion, a handle portion opposite the barrel portion, and a motor housing portion between the barrel portion and the handle portion. The percussion tool also includes an electric motor positioned within the motor housing portion and a percussion mechanism driven by the motor and including a striker supported for reciprocation in the housing. The striker defines a striker axis in a reciprocating direction. The percussion tool further includes a battery receptacle supported by the housing and a battery pack removably coupled to the battery receptacle for providing power to the motor. The battery pack and the battery receptacle define a battery axis extending longitudinally through the battery pack and battery receptacle. The striker axis and the battery axis are parallel.

Method for the open-loop and closed-loop control of a power tool, in particular a chipping hammer, having a drive, a control device, a sensor device, a transmission device and a handle apparatus, wherein the handle apparatus contains a lever element with a signal transmitter, said lever element being pivotable relative to the sensor device. The method includes: sensing a first and second position of the signal transmitter by the sensor device; determining an acceleration of the signal transmitter from the first position to the second position by the control device; setting a first rotational speed for the drive by the control device for the output of a first impact energy value of the transmission device when the determined acceleration reaches a first predetermined threshold value or setting a second rotational speed for the drive by the control device for the output of a second impact energy value of the transmission device when the determined acceleration reaches a second predetermined threshold value. A handle apparatus on a power tool, in particular a chipping hammer, is also provided.

A hammer has a head connected to a lightweight handle with a center of gravity that is proximate to the head of the hammer and separated from the base of the handle by 85%-95% of the total hammer length, measured from the base of the handle to the top side of the head. The handle weight is between 10%-20%. Accordingly, the lighter handle allows the center of gravity of the hammer to be within 85%-95% of the total hammer length from the base of the handle while maintaining a comfortable head weight between 14 oz. and 25 oz. The hammer also has inflection point proximate to the base of the handle providing multiple gripping sections to allow a user to grip the handle in different locations and at different gripping angles that move relative to the longitudinal axis of the hammer.

A pneumatic hammer including a connector for connection to an external compressed air source and a striking mechanism. The striking mechanism includes a housing and a piston arranged for reciprocating motion in the housing. The striking piston has front and rear piston portions. The piston and the housing form front and rear spaces. A compressed air conduit is arranged in airflow communication with the front space via a second passage in the housing, at which second passage a first valve is arranged. There is an intermediate space between the front and rear piston portions and the housing. The control unit is alternately subjected to air pressure of the rear space with respect to the intermediate space during reciprocating motion of the piston. The control unit controls the first valve based on air pressure to alternately supply compressed air to the front space and achieving a return movement of the piston.

A hand-held power tool includes a tool holder for holding a tool on a working axis, a pneumatic striking mechanism for striking the tool, and an absorber, which includes a bending spring, situated transversely to the working axis, and a mass body. A countershaft is driven by the motor around a rotation axis which runs in parallel to the working axis. A wobble drive for driving the pneumatic striking mechanism is situated on the countershaft. In addition, a cam disk is situated on the countershaft and includes a cam which projects in a start-up direction which runs in parallel to the working axis. The bending spring includes a counterpiece provided relative to the cam. The cam, which abuts the counterpiece, pretensions the bending spring in the start-up direction.