A percussion tool comprises a housing and an electric motor positioned within the housing. The percussion tool further comprises a battery pack supported by the housing for providing power to the motor. The battery pack includes a plurality of battery cells having a nominal voltage of up to 120 Volts. The percussion tool further comprises a percussion mechanism driven by the motor and including a striker supported for reciprocation in the housing. The percussion tool has a ratio of impact energy to mass that is greater than or equal to 2.5 Joules/kilogram.

An electric power tool includes a motor, a driving side member, and a driven side member. The driving side member and the driven side member have mutually opposed surfaces. A plurality of cam teeth are respectively disposed on concentric circles on the opposed surfaces. The plurality of cam teeth have meshing surfaces inclined at predetermined lead angles. A torque limiter is formed to disengage the engagement of the meshing surfaces of the cam teeth by moving the one member in a separation direction from the other member when load of the driven side member increases. The respective cam teeth are formed such that the lead angles of the meshing surfaces are different between a forward rotation side and a reverse rotation side. A transmission torque transmitted from the driving side member to the driven side member is equal between the forward rotation and the reverse rotation.

To prevent, for example, a tube in a case from blocking an oil port, an oil unit includes a case that contains oil, a blade inside the case, an output shaft holding the blade and protruding from the case, at least one oil port formed on the case, a hollow tube adjacent to an inner surface in which the at least one oil port is open in the case, and a flow channel definer positioning the tube adjacent to an opening of the at least one oil port in the inner surface at a predetermined position and defining a flow channel of oil to flow into the case through the opening.

To prevent, for example, a tube in a case from blocking an oil port, an oil unit includes a case that contains oil, a blade inside the case, an output shaft holding the blade and protruding from the case, at least one oil port formed on the case, a hollow tube adjacent to an inner surface in which the at least one oil port is open in the case, and a flow channel definer positioning the tube adjacent to an opening of the at least one oil port in the inner surface at a predetermined position and defining a flow channel of oil to flow into the case through the opening.

An electropneumatic impact mechanism for an electric hand-held power tool, in particular a hammer drill and/or chipping hammer, wherein the impact mechanism has a transmission housing, a guide tube arranged at least partially in the transmission housing, an exciter piston that is movable in the guide tube, a connecting rod coupled to the exciter piston, and an eccentric wheel which is designed as an externally toothed gearwheel and is coupled to the connecting rod on one side and is mounted so as to be rotatable with respect to the transmission housing about an axis of rotation on the other side, an axial gap, preferably for optionally receiving at least part of a lubrication space separating element, is provided between an eccentric wheel surface facing the connecting rod and a connecting rod surface facing the eccentric wheel.

An electropneumatic impact mechanism for an electric hand-held power tool, in particular a hammer drill and/or chipping hammer, wherein the impact mechanism has a transmission housing, a guide tube arranged at least partially in the transmission housing, an exciter piston that is movable in the guide tube, a connecting rod coupled to the exciter piston, and an eccentric wheel which is designed as an externally toothed gearwheel and is coupled to the connecting rod on one side and is mounted so as to be rotatable with respect to the transmission housing about an axis of rotation on the other side, an axial gap, preferably for optionally receiving at least part of a lubrication space separating element, is provided between an eccentric wheel surface facing the connecting rod and a connecting rod surface facing the eccentric wheel.

An electric power tool includes a motor, a driving side member, and a driven side member. The driving side member and the driven side member have mutually opposed surfaces. A plurality of cam teeth are respectively disposed on concentric circles on the opposed surfaces. The plurality of cam teeth have meshing surfaces inclined at predetermined lead angles. A torque limiter is formed to disengage the engagement of the meshing surfaces of the cam teeth by moving the one member in a separation direction from the other member when load of the driven side member increases. The respective cam teeth are formed such that the lead angles of the meshing surfaces are different between a forward rotation side and a reverse rotation side. A transmission torque transmitted from the driving side member to the driven side member is equal between the forward rotation and the reverse rotation.

A hammer drill is provided including a housing, a motor mounted within the housing, and a hammer mechanism. The hammer mechanism includes a crank plate or a wobble plate driven by the motor, a con rod coupled to the crank plate or the wobble plate, a piston reciprocatingly driven by the con rod along a longitudinal axis, a ram and a beat piece. At least one of the wobble plate or the con rod is made of sintered steel.

A hammer drill is provided including a housing, a motor mounted within the housing, and a hammer mechanism. The hammer mechanism includes a crank plate or a wobble plate driven by the motor, a con rod coupled to the crank plate or the wobble plate, a piston reciprocatingly driven by the con rod along a longitudinal axis, a ram and a beat piece. At least one of the wobble plate or the con rod is made of sintered steel.

An impact tool includes a housing; and a motor, a tubular tool holder, a driving mechanism, a rotation shaft, a driving mechanism housing region inside the housing. The tool holder has a distal end on which a bit is mountable. The driving mechanism is configured to hammer the bit. The rotation shaft is disposed in the driving mechanism and rotates by a rotation of an output shaft of the motor. The driving mechanism housing region houses the driving mechanism in a sealed state inside the housing. The air escape path that releases air inside the driving mechanism housing region to outside of the driving mechanism housing region is formed inside the rotation shaft while an inlet of the air escape path is formed on an outer peripheral surface of the rotation shaft.