A cooling gas is fed from an ejection nozzle into the interior of a through-hole which is formed in a radially central portion of a main spindle, and which penetrates through said main spindle in an axial direction. The cooling gas passes through radial venting holes provided in a plurality of locations, in the circumferential direction, in an axially intermediate portion of the main spindle, is fed into axial venting holes provided in a plurality of locations, in the circumferential direction, extending from one axial-direction end of the main spindle to an intermediate portion thereof, is caused to flow through the axial venting holes, and is discharged from discharge holes.

A hydraulic hammer is provided. The hydraulic hammer includes a housing member. The hydraulic hammer also includes a power cell disposed within the housing member. The power cell includes an outer casing. The hydraulic hammer also includes a work tool operatively coupled with the power cell. The hydraulic hammer also includes one or more bushing parts arranged within the outer casing of the power cell. The one or more bushing parts are adapted to guide the work tool during an operation of the hydraulic hammer. The one or more bushing parts include a first surface and a second surface spaced apart from the first surface. The hydraulic hammer also includes a wear indicating system for indicating a wear of the one or more bushing parts with respect to the first surface. The wear indicating system includes a first passage and a second passage.

A hydraulic hammer is provided. The hydraulic hammer includes a housing member. The hydraulic hammer also includes a power cell disposed within the housing member. The power cell includes an outer casing. The hydraulic hammer also includes a work tool operatively coupled with the power cell. The hydraulic hammer also includes one or more bushing parts arranged within the outer casing of the power cell. The one or more bushing parts are adapted to guide the work tool during an operation of the hydraulic hammer. The one or more bushing parts include a first surface and a second surface spaced apart from the first surface. The hydraulic hammer also includes a wear indicating system for indicating a wear of the one or more bushing parts with respect to the first surface. The wear indicating system includes a first passage and a second passage.

A clearance control system for a hydraulic hammer is disclosed. The hydraulic hammer includes a housing member, a power cell disposed within the housing member, a wear member disposed between the housing member and the power cell, and a clearance control system for controlling the predefined clearance between the wear member and the power cell. The clearance control system includes a mounting boss and a fastening member disposed on the mounting boss. A first end of the fastening member is configured to receive an input from an operator and the second end is configured to contact with the first surface of the wear member. The fastening member is configured to move along a central axis defined by a threaded hole of the mounting boss to move the wear member towards the power cell, to control the predefined clearance between the wear member and the power cell.

A production method provides for punching holes in a metal strip, cold-forming the metal strip to form a guide tube, and joining the lengthwise edges of the metal strip to each other by a seam or teeth so as to create a uniform material. Subsequently, a piston-like striker is inserted into the guide tube.

A sleeve is disclosed for use with a hammer. The sleeve may have a generally cylindrical body with a first end and a second end. The sleeve may also have a plurality of channels spiraling at least partially around the generally cylindrical body between the first and second ends.

A sleeve is disclosed for use with a hammer. The sleeve may have a generally cylindrical body with a first end and a second end. The sleeve may also have a plurality of channels spiraling at least partially around the generally cylindrical body between the first and second ends.

A vibration damping handle assembly is disclosed which has a control handle having an indentation formed therein, an insert adapted for fitting into the indentation formed in the control handle, an adapter sleeve having an exterior surface and an interior surface having an indentation formed in the interior surface with the indentation adapted for receiving the insert fitted into the indentation formed in the control handle, and an outer sleeve member for fitting on the exterior surface of the adapter sleeve.

A cutting tool mechanism 11 for providing a cutting, abrading or grinding action is disclosed. The mechanism 11 has an inner circular part 17 having teeth 19 extending radially outwardly, a surrounding circular part 25 having inner teeth 27 extending radially inwardly. The circular parts 17 and 25 co-operate by engagement their teeth 19 and 27. Rotation of one circular part causes the other to move constrained by the engagement of the teeth in an orbital, oscillatory or impact motion. An input coupling 81 is provided for transmission of rotary motion, and an output coupling 37 is provided to transmit said orbital, oscillatory or impact motion to a blade 13. In further embodiments, the surrounding circular part 25 can be provided with outwardly extending teeth and surrounded by a further outer circular part with inwardly extending teeth, to cooperate with the outwardly extending teeth, to provide more complex orbital, oscillatory or impact motion.

The present disclosure relates to a method for producing polycrystalline silicon fragments. The process includes (a) providing a polycrystalline silicon rod, (b) working the surface of the silicon rod by means of a hammer or needle hammer to remove at least a portion of a layer of the surface of the polycrystalline silicon rod, and (c) reducing the silicon rod to fragments. Wherein an amount of impact energy expended by the hammer and/or needle hammer is from 1 J to 15 J.