B25D2250/035

Striking tool
11529724 · 2022-12-20 · ·

A striking tool restricting movement of an intermediate member toward a striker reliably prevents no-load strokes. A hammer drill includes a cylindrical tool holder holding a tip tool, a motor, a piston that reciprocate with rotation from the motor, a striker that reciprocate in cooperation with the piston, an intermediate member reciprocably accommodated in the tool holder between the striker and the tip tool and in contact with a rear end of the tip tool at a normal strike to indirectly transmit a strike from the striker to the tip tool, and at least two ring members that move in a front-rear direction accommodated in the tool holder at a front of the intermediate member between the tool holder and the intermediate member. At least one ring member is made of metal.

Rotary hammer

A rotary power tool includes a housing, a spindle defining a working axis, and a motor supported by the housing. The motor is operable to drive the spindle. The rotary power tool also includes a handle movably coupled to the housing and a vibration isolating assembly disposed between the housing and the handle. The vibration isolating assembly attenuates vibration transmitted from the housing to the handle. A battery pack is removably coupled directly to the handle and configured to provide power to the motor.

Percussion unit

A percussion unit for a rotary hammer and/or percussion hammer includes a control unit that is configured for open-loop and/or closed loop control of a pneumatic percussion mechanism. In at least one operating state in which the control unit changes from an idle mode to a percussion mode, the control unit is configured to adjust at least one operating parameter temporarily to a starting value.

CONTROL METHOD FOR A HAMMER DRILL

The control method for a hammer drill (1) provides the following steps. During basic operation, the motor (5) rotates at an operating speed for the drilling operation with chiseling action in order to rotationally drive the tool holder (2) and to drive the hammer mechanism (6) with a nominal striking power. The torque coupling (21) is monitored with the aid of a sensor (26). If a disengagement of the torque coupling (21) occurs, the striking power of the hammer mechanism (6) is reduced to below 10% of the nominal striking power during a disengagement of the torque coupling (21), and the torque coupling (21) is driven. When the disengagement of the torque coupling (21) ends, the striking power of the hammer mechanism (6) is increased to the nominal striking power and the torque coupling (21) is driven at the operating speed for the drilling operation with chiseling action.

Power Tool

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.

Power tool

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.

Hand-held power tool

The A hand-held power tool includes a tool holder 2 for holding a tool and a pneumatic striking mechanism for periodically generating impacts on the tool held in the tool holder. The striking mechanism includes a guiding tube, an exciter piston, a striker, a pneumatic chamber closed by the exciter piston and the striker in the guiding tube, and a compensating opening in the guiding tube for ventilating the pneumatic chamber. A cap covers the compensating opening on an outside of the guiding tube. The cap is open in an opening direction which is largely tangential to the guiding tube.

HANDHELD POWER TOOL
20210001463 · 2021-01-07 ·

A handheld power tool 1 has a tool socket 2 to hold a tool along a working axis 11. A motor-driven, pneumatic striking mechanism 6 has an exciter 17 which is driven by a motor 5, a striker 14 that is coupled to the exciter 17 via a pneumatic chamber 19, and an intermediate striker 22 arranged on the working axis 11 in the striking direction 12 behind the striker 14. A ventilation opening 30 connects a cavity 29 situated between the striker 14 and the intermediate striker 22 to the environment. A valve 38 that closes the ventilation opening 30 is opened when actuated by the intermediate striker 22 when the intermediate striker 22 is moved into its working position counter to the striking direction 12.

Percussive 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.

Striking hand-held machine tool
10821590 · 2020-11-03 · ·

A hand-held machine tool 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 between the exciter piston and the hammer, and a striker 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.