Andreas Stihl Ag & Co.

Andreas Stihl

Lothar Ulrich

Helmut Lux

Phillip Neumann

A vibration damper is disposed between two components ( ) of a portable handheld work apparatus ( ). The vibration damper is held especially between a housing ( ), which holds an internal combustion engine ( ), and a handle ( ) which is fixed on the housing ( ) for guiding the work apparatus ( ). The vibration damper includes a coil spring ( ) and respective attachment elements ( ) at the ends ( ) of the coil spring. A coupling member ( ) is provided to ensure that the work apparatus can be guided notwithstanding a break of a coil spring. The coupling member ( ) projects through the coil spring ( ) and bridges the axial distance ( ) between the attachment elements ( and ). The coupling member ( ) is connected to each attachment element ( ) so that it cannot separate therefrom.

vibration damper between two components

The invention is directed to a portable handheld work apparatus including a motor-driven chain saw, cutoff machine and the like. The work apparatus includes a housing and an internal combustion engine mounted in the housing for driving a work tool. The housing defines a space from which said engine draws combustion air and a fan wheel is disposed in the housing for generating a cooling-air flow which leaves the fan wheel in a direction tangential to the periphery of the fan wheel for cooling the engine. The housing has a U-shaped channel for conducting the cooling-air flow. The U-shaped channel is disposed so as to face toward the fan wheel with the base wall thereof being disposed at a predetermined spacing from the periphery of the fan wheel. The U-shaped channel has a pass-through formed in the base wall at a pregiven spacing downstream from the fan wheel for passing a portion of the cooling-air flow to the space as combustion air for the engine. The pass-through defines a plane and a center axis perpendicular to the plane. The U-shaped channel is configured to impart a predetermined direction of flow to the cooling-air flow at the region of the pass-through and the center axis and the predetermined direction of flow conjointly define an angle .beta. having a value in a range of approximately 70.degree. to 180.degree..

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Schwaikheim, Germany

Lothar Ulrich