Andreas Stihl Ag Co. Kg

Ralf Cornelsen

Harald Schliemann

Wolfgang Weissert

Norbert Apfel

Gerd Densborn

Manfred Schumacher

A handheld work apparatus has a blower wheel. The blower wheel is held via a nut on the shaft in a manner locked against rotation by frictional force. A thread moment of friction is transmittable between the nut and the shaft via a thread section. A first moment of friction is transmittable between the nut and the blower wheel via a first friction contact surface. The first friction contact surface is configured such that, at a minimum tightening torque of the nut, the first moment of friction is greater than the thread moment of friction. As a result, during the operation of the work apparatus when there is a relative movement between the blower wheel and the shaft, the blower wheel moves the nut along therewith. The nut retensions the blower wheel against the shaft. The second friction contact surface runs conically with respect to the rotational axis.

Handheld work apparatus

A hand-held work implement having a tool has a braking device for the tool that includes a brake band which wraps around a brake drum. The brake band and the brake drum undergo friction as they move relative to one another during braking. At least one of the band or drum comprises an austenitic steel, a duplex steel, super duplex steel, a nickel-base alloy or a cobalt-base alloy and has a base body and a marginal layer. The hardness of the marginal layer is approximately 150% to approximately 600% of the hardness of the base body and the carbide proportion in the marginal layer is less than approximately 0.5% by weight. A process for production of the foregoing includes diffusing carbon and/or nitrogen into a marginal layer at a temperature of less than 500&#xb0; C.

Growing community of inventors

Aspach, Germany

Ralf Cornelsen