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.

A reciprocating tool includes a motor, a driving mechanism, a body housing, a movable part, and a vibration control mechanism. The driving mechanism includes a reciprocating member configured to reciprocate in a first direction. The movable part is connected to the body housing via a first elastic member and a second elastic member to be relatively movable in the first direction. The vibration control mechanism includes at least one weight configured to move in a direction opposite to the reciprocating member. The center of gravity of the at least one weight is offset from the driving axis in a second direction. In the second direction, the first elastic member is closer to the center of gravity than the second elastic member. A load of the first elastic member when the movable part is placed in a closer position is smaller than a load of the second elastic member.

A percussion tool comprises a housing and an electric motor positioned within the housing. The motor has a nominal outer diameter of up to about 80 mm and is operable to output at least about 2760 W. 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 80 Volts and a sustained operating discharge current of between about 40 A and about 60 A. 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.

A percussion tool comprises a housing, an electric motor positioned within the housing, a percussion mechanism driven by the electric motor and including a striker supported for reciprocation in the housing, a battery pack removably coupled to the housing for providing power to the electric motor when coupled to the housing, and an electronic controller including an electronic processor and a memory. The electronic controller is coupled to the electric motor and configured to activate the motor and determine whether the percussion tool is in a loaded condition. In response to determining that the percussion tool is in the loaded condition, the electronic controller is configured to operate the motor in accordance with a predetermined profile and in response to determining that the percussion tool is in a no load condition, the electronic controller is configured to operate the motor at a no-load speed.

An impacting apparatus may include a frame, an arm movably mounted on the frame, a weight mounted on the arm to rotate about a rotation axis eccentric to a center of mass of the weight, and a weight rotation assembly rotatably mounting the weight on the arm. The rotation assembly may comprise a rotation shaft mounted on the arm and the weight, and a clutch. The apparatus may include a rotation assembly configured to rotate the rotation shaft with respect to the arm to thereby cause rotation of the weight with respect to the arm, and an impact member movably mounted on the frame and being aligned with the impact location on the arm such that the arm impacts the impact member, with the impact member having an impact surface.

Vibrations resulting from a reciprocating piston and vibrations resulting from a rotating crank shaft are reduced effectively. A housing for a hammer drill accommodates, at a position at which a cap closes a supply port, a counterweight movable in cooperation with a crank mechanism to reduce vibrations in a striking axis direction resulting from a reciprocating piston, and a second counterweight rotatable in cooperation with the crank mechanism to reduce vibrations in a rotational direction resulting from a crank shaft.

A method for reducing vibrations in a percussion tool includes activating, using an electronic controller of the percussion tool, the motor of the percussion tool, determining, using the electronic controller, that the percussion tool is in a loaded condition, and operating, using the electronic controller, the motor in accordance with a predetermined profile in response to determining that the percussion tool is in the loaded condition. The method also includes determining, using the electronic controller, that the percussion tool is in a no-load condition and operating, using the electronic controller, the motor with reduced speed in response to determining that the percussion tool is in the no-load condition.

A dust collecting system includes a power tool and a dust collector. The power tool includes at least one battery-mounting part, a first motor, a driving mechanism and a body housing. The at least one battery-mounting part is each configured to removably receive a battery. The first motor is configured to operate with electric power supplied from the battery. The driving mechanism is configured to drive the tool accessory by power of the first motor. The body housing houses the first motor and the driving mechanism. The dust collecting system includes a control device configured to control operation of at least one of the power tool and the dust collector according to a state of the whole dust collecting system.

A sliding center of gravity hammer is disclosed herein allows the user to slide a heavy weight to various positions in the barrel of the hammer for different applications. When more force is needed to drive a nail, the heavy weight could be locked in the first position which is closest to the hammer head. When less force is needed, the heavy weight could be locked in the third position which is closest to the handle end. The embodiment allows the user to adjust the weight of the hammer to the user's needs when working on many different applications which increases the operation efficiency and reduces risk of injury to the user.

A percussion tool comprises a housing and an electric motor positioned within the housing. The motor has a nominal outer diameter of up to about 80 mm and is operable to output at least about 2760 W. 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 80 Volts and a sustained operating discharge current of between about 40 A and about 60 A. 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.