Andreas Stihl Ag Co. Kg

Sebastian Lechner

Denis Ehrler

Marc Schmid

Alexander Maier

Jörg Bläsi

Simon Jetter

Dirk Förstner

Jan Geffers

A motorized working apparatus includes a housing having an air inlet, an air guide leading from the air inlet into the housing, and an air filter which is curved hood-shaped outwardly and covers the air inlet of the housing. The air filter includes a filter frame body with a filter-fabric-free air outlet face facing the air inlet of the housing and with a window frame structure protruding over the filter-fabric-free air outlet face and having at least one window region. A filter fabric occupies the at least one window region, and a fixation releasably fixes the filter frame body to the housing. The window frame structure has frame webs which delimit the at least one window region and which protrude relative to the filter fabric towards an air supply side in the at least one window region and include web side edges which run sloping at an obtuse angle relative to adjacent window planes, and/or the fixation includes a pre-fixing clamping holding arrangement and a final fixing holding arrangement which are independent of each other, and/or the window frame structure of the air filter protrudes over the filter-fabric-free air outlet face in the shape of a roof with a triangular cross-sectional form.

Motorized working apparatus and air filter

A hand-guided working apparatus has a radial fan. The radial fan includes a fan impeller and an air duct, which has a spiral portion surrounding the fan impeller and has a duct cross section, which increases in the air flow direction. An outlet funnel portion adjoins the spiral portion, widens in a funnel shape in the air flow direction and has a radially inner boundary wall and a radially outer boundary wall. The outlet funnel portion ends in an air outlet opening, the outlet width of which is smaller than an outside diameter of the fan impeller. The radially inner and/or the radially outer boundary wall of the outlet funnel portion has a curvature opposed to that of the spiral portion. An intermediate wall is arranged in the outlet funnel portion, between the radially inner and the radially outer boundary wall. The intermediate wall extends with a curvature opposed to that of the spiral portion and divides the outlet funnel portion into two component portions, each widening in the shape of a funnel in the air flow direction.

Hand-guided working apparatus having a radial fan

Growing community of inventors

Waiblingen, Germany

Sebastian Lechner