Tool fitting device for a power tool, in particular a chipping hammer, including—a holding device for receiving and holding a tool shank, a retention element extending at least around a section or sections of the holding device, and a dust protection device for preventing the penetration of dust into the tool fitting device. The dust protection device includes at least one first dust stripping element, at least one fixing bead, and at least one sealing lip element, wherein the sealing lip element is positioned in front of the retention element in the axial direction. Dust protection device for use in a tool fitting device.

The hydraulic rotary-percussive hammer drill includes a fluid injection portion including a fluid feed-in inlet and an annular inner groove fluidly connected to the fluid feed-in inlet; a shank including a fluid injection conduit fluidly connected to the annular inner groove; front and rear main sealing gaskets disposed on either side of the annular inner groove and configured to cooperate with a first shank portion of the shank; a rear backup sealing gasket located at the rear of the rear main sealing gasket and configured to cooperate with a second shank portion of the shank; a leakage passage defined between the shank and the fluid injection portion; pressure drop generation means configured to generate pressure drops in the leakage passage when a leakage flow flows in the leakage passage.

A pressure accumulator, rock breaking machine and method of storing pressure energy. The accumulator includes a casing and an elastic membrane arranged inside the casing. The membrane divides an inner space of the casing into two separate pressure spaces. A gas space is prefilled with pressurized gas. On the opposite side of the membrane is a hydraulic space for receiving hydraulic fluid. The membrane is a hat-like element having side walls, a mounting flange at its open end and a closed top end. The mounting flange of the membrane is mounted between the casing and a flange element. The accumulator is without a screen. The flange element is provided with a sealing for sealing a piston.

A vibration reducing structure of pneumatic hammer includes a handle having a concave room with a bottom wall and an air inlet channel communicating with the concave room. A control valve is disposed in the air inlet channel. A movable inner tube shell is accommodated in an outer tube shell coupled with the concave room and extends a rear bucket portion into the concave room. A movable hammer member, an air inlet valve for activating the hammer member and a hole communicating the air inlet channel to the air inlet valve are disposed in the inner tube shell. An air room is formed between the bottom wall and an end wall of the inner tube shell. A communicating channel communicates the air inlet channel to the air room for air with high pressure entering the air room.

A power tool contains one or more moving parts coated with a lubricant to reduce friction. The lubricant is intended to be sealed within a housing of the power tool. In order to better prevent leakage of the lubricant to the exterior of the housing, the housing and/or a component supported by the housing includes a part exhibiting oil repellency. The oil repellency is preferably imparted at least at a junction of the housing and the component supported by the housing. The oil repellency may be imparted by applying a fluorine-based coating or a nanocoating to the junction. In addition or in the alternative, the oil repellency may be imparted by forming a portion or all of the housing from a resin material containing an oil-repelling component and/or by attaching an oil-repellant component at or proximal to the junction.

A seal of 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 is a sealing ring having an outer periphery provided with several projecting elements, which are slanted. The projecting elements generate torque in the sealing ring when being pushed in a transverse direction during use of the breaking hammer. Thus, the sealing ring may rotate relative to the tool.

A sound suppressing device for reducing the sound made when using a piece of equipment or tool is disclosed. The sound suppressing device includes: an outer shell, a window in the top of the outer shell, a filler inside the outer shell, and a containment seal for the filler. The sound suppressing device has an opening extending between its top and bottom that is sized and configured to fit around a portion of the body of the tool that will be adjacent the work piece when the tool is in use.

A power tool for chiseling and drilling includes a housing, a motor disposed inside the housing, and a pneumatic percussion mechanism. An operation mode selector switch is disposed on the housing and has a first operation mode setting and a second operation mode setting where the first operation mode setting activates the pneumatic percussion mechanism and the second operation mode setting deactivates the pneumatic percussion mechanism. A valve has an inlet-port formed inside the guiding tube and an outlet-port formed outside the guiding tube where the valve is connected to the operation mode selector switch. The valve is closed in the first operation mode setting which disables an air exchange between the inlet-port and the outlet-port and the valve is open in the second operation mode setting which enables the air exchange between the inlet-port and the outlet-port.

This hydraulic percussion apparatus, includes a guide body; a striking piston which is slidably mounted inside the guide body; a sealing device which is mounted in an annular retaining groove provided on the guide body so as to produce a sealing between a first fluid passage and a second fluid passage. The sealing device comprises includes an inner sealing ring including an inner sealing portion provided with a sealing lip sealingly cooperating with the striking piston, an annular protection portion which is internally delimited by a converging protection surface converging towards the sealing lip, an annular groove which is disposed between the sealing lip and the converging protection surface, and a balancing channel comprising first and second ends opening respectively into the annular groove and into an outer surface of the annular protection portion.

An electropneumatic impact mechanism for an electric hand-held power tool, in particular a hammer drill and/or chipping hammer, wherein the impact mechanism has a transmission housing, a guide tube arranged at least partially in the transmission housing, an exciter piston that is movable in the guide tube, a connecting rod coupled to the exciter piston, and an eccentric wheel which is designed as an externally toothed gearwheel and is coupled to the connecting rod on one side and is mounted so as to be rotatable with respect to the transmission housing about an axis of rotation on the other side, an axial gap, preferably for optionally receiving at least part of a lubrication space separating element, is provided between an eccentric wheel surface facing the connecting rod and a connecting rod surface facing the eccentric wheel.