Hilti Aktiengesellschaft

Christoph Dieing

Rainer Ontl

Damir Cehajic

Frank Kohlschmied

Christian Rehekampff

Oliver Ohlendorf

Axel Fischer

The hand-held power tool has a tool holder () for holding a tool () along a working axis (). A hammer mechanism () has a striker () that is moved periodically along the working axis at an impact rate. A drive control () of the hammer mechanism () sets the impact rate to a set point value. A vibration absorber () has an oscillator () that moves along the working axis () about a resting position and one or multiple springs () that drive the oscillator () back into the resting position. A calibration phase comprises the following steps: detection of an acceleration using the acceleration sensor (); determination of a minimum of the acceleration by varying the impact rate in a range of between 90% and 110% of the set point value; and adjusting the set point to the impact rate associated with the ascertained minimum.

Control method for a hand-held power tool

A hand-held power tool has a tool holder for holding a tool along a working axis. A hammer mechanism has a striker that is moved periodically at an impact rate along the working axis between a turning point in the proximity of the tool and a turning point remote from the tool. A drive control of the hammer mechanism sets the impact rate to a set point value. A vibration absorber has an oscillator that moves along the working axis about a resting position and one or multiple springs that drive the oscillator back into the resting position. A first sensor is used to determine a phase of the motion of the striker. A sensor is used to determine a first phase of a compression point of the hammer mechanism. Another sensor is used to determine a second phase of a turning point in the proximity of the tool, of the hammer mechanism. A damping controller adapts the set point value in such a way that a phase difference between the first phase and the second phase is less than a threshold value.

Hand-held power tool and control method therefor

A hand-held power tool is disclosed. The tool has a tool receptacle for holding a chiseling tool. A pneumatic percussion mechanism of the hand-held power tool includes a striker, an exciter and a guide tube. The striker is designed to apply impacts in the impact direction to the tool. The exciter is motor-driven. The striker is coupled by an air spring to the reciprocating movement of the exciter. The striker abutting the guide tube is guided along a working axis. During a movement between an impact position and the exciter, the striker is guided with a constant guide length on the guide tube and if the impact position is exceeded in the impact direction, the guide length is reduced. The hand-held power tool is equipped with an inclined guide, which inclines the striker relative to the working axis when the impact position is exceeded.

Power tool

A handheld power tool is disclosed. The tool has a housing, a hammer mechanism and a torque coupling. The hammer mechanism includes a beater which is movably guided along the working axis in the guide tube. The guide tube is mounted in a suspension attached to the housing so that it is movable along the working axis. The torque coupling is mounted on the guide tube and is supported on the suspension in the impact direction. The guide tube is supported on the torque coupling in the impact direction. The guide tube may be shifted with respect to the housing in the impact direction such that the torque coupling is shifted relative to the housing through the guide tube in a positively guided manner.

Handheld power tool

A hand-held power tool () includes a drive () located in the power tool housing () for driving a working tool (), and a torsional pendulum () at least partially mounted on the housing () for compensating vibrations generated by the drive ().

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Isny, Germany

Christoph Dieing