An insert bushing arrangement of a breaking hammer, a breaking hammer and a method of supporting a breaking tool of a breaking hammer is provided. The insert bushing arrangement includes a bearing support inside which an insert bushing is mountable. Between the bearing support and the insert bushing is one or more intermediate material layers for preventing jamming of the components.

A roller bearing for at least one set of roller bodies, which are disposed in an annular manner, the roller bearing having at least one track element with a track, on which the roller bodies are provided for rolling. The track comprises a track base having a circular circumferential line. The track element comprises, on each axial side of the track base, a shoulder or a rim for the roller bodies, each shoulder or rim having a circular circumferential line. The track element is formed such that, as viewed perpendicular to the planes defined by the circumferential lines, all center points of the three circumferential lines are different from each other.

A heatsink structure for a pile driver includes a rotation seat, a pivot base, a pile driver gear unit, and at least one radiating pipe. The rotation seat is pivotally connected with the pivot base. The pile driver gear unit is mounted in the pivot base and includes a receiving space and a vibration device. A pump device is mounted in the receiving space of the pile driver gear unit. The at least one radiating pipe is mounted on the pivot base. Thus, the lubricating oil in the receiving space of the pile driver gear unit is pumped by the pump device during operation and is delivered to the at least one radiating pipe so that the at least one radiating pipe cools down and carries away the heat of the lubricating oil.

A hammer drill includes a housing inside which a motor, a tubular tool holder, a driving mechanism, a rotation conversion member, and an inner housing are disposed. The driving mechanism is configured to perform at least one of rotation actuation of the tool holder and hammering actuation of a bit. The inner housing supports the driving mechanism, supports the tool holder via a first bearing, and supports an output shaft via a second bearing. The inner housing is divided into a front housing holding the first bearing and a rear housing that is formed in a separate body from the front housing and holds the second bearing. The inner housing is formed by connecting the front housing to the rear housing in an axis line direction of the tool holder. A seal member sealing outside space of the inner housing inside the housing is disposed in the front housing.

An apparatus for punching an anchor bolt insertion hole is disclosed. The apparatus enables punching work for forming the anchor bolt insertion hole, of which the bottom side is wider than an inlet, on a panel surface for constructing a concrete structure to be performed regardless of the skill of a worker. During operation, the apparatus provides the movement direction of a hammer drill into the vertical direction and the inclination direction so as to enable precise punching work, and doubly arranges springs, which are elastic devices for adjusting the movement range of the hammer drill, so as to uniformly maintain the angle and size for cutting a wall such that a cross-sectional diameter is large at a portion adjacent to the bottom of the anchor bolt insertion hole.

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.

An electric vibration driver drill as one example of an electric power tool includes the gear housing, the vibration mechanism and the clutch mechanism each located inside the gear housing, the mode switching ring (vibration switching ring) configured to operate the vibration mechanism and rotatably held to the gear housing, the clutch ring (clutch switching ring) configured to operate the clutch mechanism and rotatably held to the housing, and the respective balls located between the mode switching ring and the clutch ring.

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 powered tool includes a body, a cylinder, an impact piston reciprocating within the cylinder, and a mount to secure an attachment. The attachment includes a shank and a head sleeve fit over the shank and extending beyond its front end. The head sleeve includes a nozzle at its front end having a slot terminating at a muzzle. An internal hold in the head sleeve is in open communication with the slot. The front end of the shank is disposed within the internal hold and reciprocates therein. A rod is carried within the head sleeve for reciprocal movement in response to reciprocation of the shank with respect to the head sleeve. The rod includes a tongue extending from the internal hold into the slot of the nozzle. The tongue terminates inside the slot for reciprocal movement within the slot in response to reciprocal movement of the shank.

An inner-flanged bushing for a hydraulic breaker is a tubular shape having an inner flange and is made of a steel containing at least 0.55% and less than 0.70% by mass of carbon, at least 0.15% and less than 0.35% by mass of silicon, at least 0.4% and less than 0.9% by mass of manganese, at least 0.4% and less than 1.3% by mass of chromium, and at least 0.10% and less than 0.55% by mass of molybdenum, with the balance being iron and unavoidable impurities. The bushing includes a base region having a hardness of at least 30 HRC and less than 45 HRC, and a quench hardened layer formed on an inner periphery side of the base region to include an inner peripheral surface of a region including the inner flange, the quench hardened layer having a hardness of at least 55 HRC and less than 63 HRC.