A rotary hammer includes a motor, a spindle coupled to the motor for receiving torque from the motor, a piston at least partially received within the spindle for reciprocation therein, a striker received within the spindle for reciprocation in response to reciprocation of the piston, and an anvil received within the spindle and positioned between the striker and the tool bit. The anvil is configured to impart axial impacts to the tool bit in response to reciprocation of the striker. The rotary hammer also includes a retainer received within the spindle for selectively securing the striker in an idle position in which it is inhibited from reciprocating within the spindle. The retainer includes a detent member configured to engage the striker to secure the striker in the idle position, and a tensing element configured to bias the detent member radially inward toward engagement with the striker.

A handheld power tool (1) is provided, including a tool holder (2) for receiving and locking a tool (3) on a working axis (4), and including a power tool housing (6). A striking mechanism (8) includes a striker (10) for applying impacts in the impact direction (9) and an anvil (11) for absorbing the impacts and for transmitting the impacts in the impact direction (9) onto the tool (3) accommodated in the tool holder (2). A collar (18) is fastened to the power tool housing (6) and to the anvil (11). When the anvil (11) abuts a rebound impact damper (13) in the impact direction (9), the elastic collar (18) applies a force acting in the impact direction (9) onto the anvil (11).

The power cell for a hammer may comprise a head, a cylinder and a piston. The head may include a main bore, a satellite bore and a lower retainer. The main bore includes an upper chamber that includes a trough, first and second furrows, and a lock wall. The trough may include a port that extends from the main bore into the satellite bore. The lock wall may extend between the furrows. The lower retainer may be disposed in the satellite bore, and may include a core member and a jut. The core member may include a bore configured to receive a fastener. The cylinder may include a body and a protrusion on the body. The cylinder may be rotatable, wherein when in a locked position the protrusion is disposed in the port, the fastener is received in the bore, and the protrusion abuts the lock wall and the jut.

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.

The invention relates to a striking hand-held machine tool having a tool holder for holding a striking tool on a working shaft, an electric motor, and a striking mechanism. In the striking direction, the striking mechanism has an exciter piston, a pneumatic chamber, a striker, an intermediate chamber and a rivet snap following one another. A closed channel connects a first channel opening in the pneumatic chamber and a second channel opening in the intermediate chamber. A non-return valve, which shuts off during an air flow from the first channel opening to the second channel opening and opens during an air flow from the second channel opening to the first channel opening, is arranged in the channel. Arranged on the second channel opening is a shut-off valve, which is forced into a position closing the second channel opening when the rivet snap is in the working position.

A power tool comprises a housing having at least two housing parts and at least one recess, a portion of the recess provided by each housing part, and a bearing located in the recess. The power tool includes a seal comprising an elongate seal member located between the housing parts to seal at least a portion of the housing. The seal includes at least one polymeric extension part extending from the elongate seal member and in contact with an external part of the bearing without extending around the bearing. The polymeric extension part of the seal prevents the external part of the bearing from rotating with respect to the housing during use of the power tool.

A percussion mechanism contains a guide tube, an exciter piston, a hammer, a pneumatic chamber for coupling the hammer to the motion of the exciter piston, a striker, and a seat for the striker. The hammer has a striking point, defined by a striking surface of the striker when the striker lies against the seat. A check valve has an outlet opening and a closing mechanism for closing the check valve against an air flow from the interior of the guide tube. The outlet opening is arranged in such a way that the outlet opening is closed by the hammer during striking operation and otherwise is open.

A hand-held tool has a tool holder for holding a striking tool on a working axis, an electric motor, and a striking mechanism. The striking mechanism has an exciter piston moved by the motor, a striker coupled to the exciter piston by a pneumatic chamber arranged between the exciter piston and the striker, and a ram arranged in the striking direction of the striker piston. In a working position the ram rests counter to the striking direction against a stop. A stationary shut-off valve has a valve seat and an elastic shut-off member, wherein the elastic shut-off member in a relaxed state has a basic form which lifts from the valve seat, and wherein in the working position the elastic shut-off member is forced by the ram into a tensioned form resting against the valve seat.

A hand-held machine tool including a tool holder for a striking tool has a motor, an impact mechanism, a spool valve, and a pneumatic chamber. The impact mechanism has an exciter piston moved by the motor, and a hammer coupled to the exciter piston via a pneumatic chamber arranged between the exciter piston and the hammer, and a striker arranged in front of the hammer in the striking direction. In a working position counter to the striking direction, the striker bears on a stop, in a starting position the striker is offset in the striking direction relative to the working position, and in a rest position the striker is offset in the striking direction relative to the starting position. In the starting position, the hammer bearing on the striker closes the spool valve and, in the rest position, the hammer bearing on the striker opens the spool valve.

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.