Hilti Aktiengesellschaft

Guenther Veik

Ralf Meixner

Hans-Joerg Rieger

Roland Schaer

Josef Schittl

Eduard Sever

Ralf Greitmann

Dragomir Ljubojevic

Marcus Flock

Christoph Würsch

Helmut Specht

Georg Studer

Stefan Teufelhart

A handheld, hand-guided cutting-off machine (), which includes a rotating cutting-off wheel, a supporting housing part (), an output shaft, which is rotatably supported around an output axis (), a drive motor, a transmission mechanism (), which connects the drive motor to the output shaft, a flange and a safety guard (), which covers the cutting-off wheel over a covering area. The cutting-off wheel is rotatably fixedly mounted on the output shaft with the aid of the flange and surrounded by the safety guard (), which is pivotable around a pivot axis. The safety guard (), the supporting housing part () and the transmission mechanism () have maximum distances from the output axis () over an outcut angle (&#x3b8;), which are less than or equal to half the flange diameter of the flange.

Handheld, hand-guided cutting-off machine

A hand-held power tool for driving a cutting or grinding working tool () includes a running gear () having a roller () and a support section () for supporting the roller (), and a locking device () for locking the roller () against rotation relative to the support section ().

Hand-held power tool

A hand-held power tool for driving a working tool () includes a drive belt (), first and second arms () longitudinally displaceable relative to each other and carrying respective deflection rollers () of the drive belt (), a belt tensioning device () located between the first and second arms () and including a spring () preloaded against the first arm (), and a displaceable pressure piston () located between the spring () and the second arm ().

Hand-held power tool with a belt tensioning device

For the automatic determination of the diameter of a tool, particularly a saw blade for an automatic wall saw, which is driven by a motor via a gear unit, the moment of inertia of the tool is used as an indicator for its diameter. Three basic solution variants are introduced. In particular, the system including a motor, gear unit and tool is treated as a dual-mass oscillator such that the elasticity of the shafts and gears is arranged as a torsion spring between the inertial masses in two discrete points while taking into account two coefficients of friction including coefficients of the known inertia of the motor rotor (&#x398;) and of the tool (&#x398;). This system can be described by equations which are then simplified by reasonable assumptions or premises. The selected formulations are solved for the moment of inertia of the tool to determine the diameter therefrom and to make an optimal adjustment for the drive possible which is adapted to the respective tool.

Method and device for the automatic determination of the diameter of a round disk-like tool driven by a motor

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Maeder, Austria

Guenther Veik