A seal for a tool of a breaking hammer, a sealing arrangement, a breaking hammer and a method of sealing a tool of breaking hammer is provided. The seal includes a resilient first seal element and a rigid second seal element. The first seal element is fastened to a seal housing and the second seal element is fastened to the first seal element. The second seal element provides mechanical protection for the first seal element.

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.

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.

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 impact tool which transmits an impact force to a tool bit supported by a casing includes: a cylinder which is attached to the casing and has an opening on one end side thereof to which the tool bit is inserted; an intermediate element which is provided in an inside of the cylinder so as to be able to move straight, has a projection projecting in a radial direction so as to regulate a range of the straight movement, and transmits the impact force to the tool bit; and passages and which communicate a space in an inside of the cylinder at a position nearer to the tool bit than the projection with the outside of the cylinder and penetrate through the cylinder in the radial direction.

An impact tool which transmits an impact force to a tool bit supported by a casing includes: a cylinder which is attached to the casing and has an opening on one end side thereof to which the tool bit is inserted; an intermediate element which is provided in an inside of the cylinder so as to be able to move straight, has a projection projecting in a radial direction so as to regulate a range of the straight movement, and transmits the impact force to the tool bit; and passages and which communicate a space in an inside of the cylinder at a position nearer to the tool bit than the projection with the outside of the cylinder and penetrate through the cylinder in the radial direction.

The present disclosure provides a sleeve for a hydraulic hammer. The sleeve includes an elongated body. The elongated body defines an outer surface, an inner surface, and a plurality of axial conduits to transmit hydraulic fluid. The elongated body further defines a plurality of radial holes extending from the plurality of axial conduits to the inner surface of the elongated body. The elongated body also defines a plurality of circumferential grooves on the inner surface. Each of the plurality of circumferential grooves is located along a longitudinal axis of the sleeve. The elongated body also defines at least one micro channel extending radially to form a fluid connection between each of the plurality of axial conduits and each of the plurality of circumferential grooves to transmit the hydraulic fluid for lubrication on the inner surface of the elongated body.

A hammer drive mechanism is provided for converting rotary drive from a motor to reciprocatory movement of an impact member of a hammer drill. The mechanism comprises a rotatable plate adapted to be rotated by the motor, an input drive member associated with the rotatable plate in an eccentric position with respect to the axis of rotation of the rotatable plate, an output drive member associated with the impact member, and a crank shaft having a respective driver adjacent each of its ends. Each driver engages with, and is complementary to a respective one of the drive members. At least one end portion of the crank shaft comprises a lubricating aperture which opens into the adjacent driver to provide a lubrication path to the engaging surfaces of the drivers and the drive members.