Andreas Stihl Ag Co. Kg

Firma Andreas Stihl Ag & Co.

Ernst Buck

Joachim Hoffmann

Arno Kinnen

Helmar Amend

Igor Klaric

Peter Bauer

Norbert Veser

Heiko Däschner

Heiko Daeschner

Frank Opelka

An ignition circuit for a combustion engine has an ignition coil and a control unit for the coil. The coil and the control unit are included in a common component as an ignition module. The module is supplied with voltage by a generator driven by the engine. A spark plug and the coil form a power circuit which includes a line segment to a reference potential outside the module. A sensor detects data of the engine and the output of the sensor is supplied to the module. The sensor is supplied with voltage via a sensor circuit. The sensor circuit and the power circuit use the line segment as a common connection to the reference potential, so that for a defect of the line segment, a missing connection to the reference potential in the high voltage circuit is recognized via the change of the sensor output signals.

Ignition circuit

A protective cover of a hand-held cut-off machine has a bracket that is secured on the exterior side of the protective cover. The bracket is locked in at least one locked position with at least one locking projection in at least one receptacle of the protective cover. The bracket is releasable from the locked position by a movement of the bracket in the release direction. A simple release of the bracket can be achieved in that the protective cover has means that move the locking projection upon movement of the bracket in the release direction at least partially out of the receptacle.

Protective cover for a hand-held cut-off machine

A portable, manually-guided implement, such as a cut-off machine, is provided and has an internal combustion engine, a cylinder of which has a combustion chamber with an exhaust gas outlet. The combustion chamber is delimited by a piston that, via a connecting rod, drives a crankshaft rotatably mounted in a crankcase. Disposed on both sides of a central plane of the cylinder are transfer channels that respectively connect the crankcase with the combustion chamber. The first end of a transfer channel is connected via an inlet window with the combustion chamber, while the second end of the transfer channel is open toward the crankcase. The transfer channels are connected with an air duct that, via a control member, supplies essentially fuel-free combustion air from an air filter. A duct section of the air duct is formed in a housing wall disposed between the carburetor and the engine cylinder.

Rigid connecting duct

A snap closure is provided for the detachable securement of a housing cover on a housing of a manually-guided implement, especially to secure an air filter cover that covers an air filter of an internal combustion engine for driving a tool of the implement. At least one snap hook is provided on one of the components that are to be secured together, namely the cover and the housing. The snap hook is provided on an end of an elastically deflectable leg that is disposed on the one component. The snap hook is tapered in the manner of a detent and when the cover is mounted on the housing the snap hook, accompanied by an elastic return force, is engagable in an undercut provided on the other component. The snap hook is deflectable in or parallel to a surface plane on the one component that carries the snap hook.

Snap closure

Growing community of inventors

Leutenbach, Germany

Ernst Buck