A tool bushing of a breaking hammer, a tool bushing arrangement, a breaking hammer and a method of mounting a tool bushing of a breaking hammer are disclosed. The tool bushing is a sleeve-like piece having a multi-shouldered outer surface with three or more successive cylindrical portions. The cylindrical portions have different diameters that match with corresponding surfaces of a bushing housing when the tool bushing is mounted. Diameters of the bushing and the bushing housing are dimensioned so that friction forces are generated when the bushing is assembled.

A percussion tool is used for performing a chiseling operation on a workpiece with a chisel. The percussion tool comprises a housing including a cylinder portion, a tool holder coupled to the cylinder portion for holding the chisel, and a percussion mechanism including a striker supported for reciprocation in the cylinder portion. The percussion mechanism is configured to impart repeated axial impacts to the chisel with the striker. The percussion tool further comprises a flange between the cylinder portion and the tool holder. Movement of the chisel within the tool holder toward the percussion mechanism is stopped by the flange.

A power tool, in particular a rotary hammer or combination hammer, containing a percussion-mechanism apparatus for generating percussion pulses on a tool, having a basic body for receiving a rear end of the tool, at least one first and second locking element, each arranged lying in radial openings of the basic body in a reversible manner in a locking position or release position, wherein, in the locking position, the rear end of the tool is held in the basic body and, in the release position, the rear end of the tool can be removed from the basic body, a locking ring for holding the at least first and second locking elements in the locking position, and a press-on element for guiding the at least first and second locking elements in a first axial direction and a second axial direction. The press-on element consists at least partially of an elastic material.

Two balls can reliably retract for smooth insertion of a tip tool into a tool holder. A hammer drill includes a tool holder, two balls in reception holes in the tool holder, a guide washer urging the balls forward in the reception holes with a coil spring, a pressure ring adjacent to a front of the guide washer, and an operation sleeve allowing the pressure ring to move backward and forward between locked and unlocked positions of the two balls. The guide washer includes, on its front surface, a projection toward the pressure ring to cause, with the pressure ring at the locked position, the guide washer to be inclined with respect to an axis of the tool holder for a first ball to move more backward than a second ball.

Two balls can reliably retract for smooth insertion of a tip tool into a tool holder. A hammer drill includes a tool holder, two balls in reception holes in the tool holder, a guide washer urging the balls forward in the reception holes with a coil spring, a pressure ring adjacent to a front of the guide washer, and an operation sleeve allowing the pressure ring to move backward and forward between locked and unlocked positions of the two balls. The guide washer includes, on its front surface, a projection toward the pressure ring to cause, with the pressure ring at the locked position, the guide washer to be inclined with respect to an axis of the tool holder for a first ball to move more backward than a second ball.

A body of an impact unit, an impact unit and a method of forming a body of an impact unit is disclosed. The body can be an elongated hollow piece including at least two body parts. The body parts are arranged successively in an axial direction of the body and are connected to each other by axial connecting joints. The connecting joints include several slanted fastening screws for connecting the body parts together.

A body of an impact unit, an impact unit and a method of forming a body of an impact unit is disclosed. The body can be an elongated hollow piece including at least two body parts. The body parts are arranged successively in an axial direction of the body and are connected to each other by axial connecting joints. The connecting joints include several slanted fastening screws for connecting the body parts together.

A rotary impact tool includes a housing, an electric motor supported in the housing, and a drive assembly. The drive assembly includes an anvil having a longitudinal bore for selectively receiving a tool bit, and a plurality of radial slots extending from the longitudinal bore through the anvil. The rotary impact tool further includes a bit holding device including a plurality of ball detents received in the respective radial slots, and a collar slidably disposed on the anvil having an interior surface for maintaining a portion of the ball detents within the longitudinal bore, and collar spring for biasing the collar rearward to a first collar position. The bit holding device further includes a helical detent spring surrounding the anvil having a continuous helical structure with a plurality of protrusions extending into the radial slots, the protrusions are for biasing the ball detents toward an open end of the bore.

To reduce size increase, a power tool includes a motor, an output shaft located frontward from the motor, rotatable by the motor, and having an insertion hole extending rearward from a front end of the output shaft, a bearing supporting the output shaft in a rotatable manner, a locking member supported by the output shaft and movable to a locking position for locking a tip tool placed in the insertion hole and to an unlocking position for unlocking the tip tool, a bit sleeve surrounding the output shaft, and movable to a movement-restricting position for restricting radially outward movement of the locking member and to a movement-permitting position for permitting radially outward movement of the locking member, and an operable member operable to move the bit sleeve and at least partly overlapping the bearing in an axial direction.

An air hammer tool having a head section defining a blind-hole and a contact surface surrounding the blind-hole, configured to be coupled with an air hammer to provide a percussive force through the contact face of the tool to an axle flange around an axle shaft flange hole, after a flange nut has been removed, to shock a cone-washer disposed therein. The design and solution to this long-felt issue allows for easier removal of the cone-washers from the axle shaft flange holes while not contacting the respective studs and lowering chances for damage of the axle componentry.