An electric tool includes a rotary wheel driven to rotate around a central axis thereof, an action member configured to bear a cutter of the electric tool, and a counterweight. The rotary wheel drives the action member such that it reciprocates linearly in a first direction. The rotary wheel simultaneously drives the counterweight such that it not only reciprocates linearly in the first direction in an opposite manner to the action member, but also performs reciprocating swinging movement in a plane perpendicular to the central axis. The first direction is parallel to the plane.

A percussion tool comprises a housing, an electric motor positioned within the housing, a percussion mechanism driven by the motor and including a striker supported for reciprocation in the housing along a first axis, and a pair of handles coupled to the housing. The handles define a second axis. The percussion tool further comprises a battery pack removably coupled to the housing for providing power to the motor when coupled to the housing. The first and second axes are contained within first and second planes, respectively, that are parallel to each other.

A percussion tool, for performing a chiseling operation on a workpiece with a chisel, comprises a housing including a front side, and rear side, and opposite lateral sides extending between the front and rear sides, a first handle coupled to a first of the lateral sides of the housing, a second handle coupled to a second of the lateral sides of the housing, the first and second handles oriented coaxially along a handle axis, an electric motor positioned within the housing, a percussion mechanism driven by the motor and including a striker supported for reciprocation relative to the housing along a striker axis, and a light source that produces light to illuminate the workpiece. The chisel is configured to deliver repeated axial impacts to the workpiece in response to receiving repeated axial impacts from the striker.

A hand-held power tool transmission closure having a base body for closing a transmission housing opening of a transmission housing of a hand-held power tool, in particular a hammer drill or a combi-hammer, wherein the hand-held power tool transmission closure includes a tube protruding from the base body, which extends in the transmission housing when the base body closes the transmission housing opening. The hand-held power tool transmission closure includes an air channel which extends in a first air channel section through the base body and in a second air channel section through the tube so that an air mass can flow through the air channel into and out of the transmission housing.

A hammer drive mechanism for a hammer strike mechanism of a hammer drill is provided including: a drive shaft capable of being rotationally driven by a motor, a rod capable of reciprocatingly driving a piston, and a conversion mechanism that converts the rotary movement of the drive shaft into a reciprocating movement of the rod. The drive shaft comprises a first part connected to the conversion mechanism and a second part capable of being rotationally driven by a motor. The second part connects to the first part via at least one dampener such that rotary movement of the second part is transferred to the first part via the at least one dampener.

A hammer drive mechanism for a hammer strike mechanism of a hammer drill is provided including: a drive shaft capable of being rotationally driven by a motor, a rod capable of reciprocatingly driving a piston, and a conversion mechanism that converts the rotary movement of the drive shaft into a reciprocating movement of the rod. The drive shaft comprises a first part connected to the conversion mechanism and a second part capable of being rotationally driven by a motor. The second part connects to the first part via at least one dampener such that rotary movement of the second part is transferred to the first part via the at least one dampener.

A work tool includes a driving motor, a rotary shaft member configured to be rotationally driven by the driving motor, a swinging member configured to be caused to swing by rotation of the rotary shaft member, a tool accessory driving mechanism configured to drive a tool accessory by swinging of the swinging member, a body housing the driving motor, the rotary shaft member, the swinging member and the tool accessory driving mechanism, and a vibration reducing mechanism configured to reduce vibration caused in the body. The vibration reducing mechanism includes a dynamic vibration reducer having an elastic member and a weight, and a connecting member connecting the weight and the swinging member. The vibration reducing mechanism is configured to reciprocate the weight via the connecting member by the swinging of the swinging member.

A percussion tool includes a housing, a percussion mechanism including a striker supported for reciprocation in the housing along a first axis, and an anti-vibration system for attenuating vibration in a direction of the first axis. The anti-vibration system includes a linkage coupling the percussion mechanism to the housing. The linkage permits relative movement between the housing and the percussion mechanism along the first axis. The anti-vibration system also includes a counterweight supported by the percussion mechanism for relative movement therewith along a second axis that is parallel with the first axis. The counterweight reciprocates out of phase with the striker to attenuate vibration in the direction of the first axis.

In a control method for a hand-held power tool, a striking mechanism is driven with an electric motor, wherein an exciter piston of the pneumatic striking mechanism is driven periodically by the electric motor and a striking piston of the striking mechanism is coupled to the exciter piston via a pneumatic chamber. The method includes detecting the acceleration of a machine housing along a striking direction of the striking piston in different phases of the movement of the exciter piston; and controlling a rotational speed of an electric motor according to the detected acceleration in the different phases.

A hand-held power tool, in particular a hammer drill or combination hammer, having a tool fitting for holding a striking and rotating tool on a working axis, an electric motor coupled to a transmission shaft, an impact mechanism, which has a striker that is moved periodically along the working axis, and having a rotary drive, which drives a guide tube carrying the tool fitting in rotation about the working axis, wherein the rotary drive is coupled to the transmission shaft via a rocker lever.