Andreas Stihl Ag Co. Kg

Andreas Stihl Ag & Co.

Michael Raffenberg

Heiko Rosskamp

Lars Bergmann

Klaus Langhans

Heinz Hettmann

Jochen Kramer

Thomas Stark

Florian Hoche

Antonio Fattorusso

Igor Klaric

Michael Grether

Matthias Müller

Peter Pretzsch

Clemens Klatt

Hans-Georg Wiedmann

Markus Pfeifer

Markus Zeller

Karsten Schmidt

Andreas Hägele

Johannes Alber

Johann Trumpf

Jörg Elfner

Fevronia Konstantinidou

Sebastian Hansen

Isgard Sabelberg

Bettina Zitzmann

Hannes Frank

Heiko Roßkamp

A fuel feed unit has a base body with an intake channel section, into which a fuel opening opens. A partition wall section divides the intake channel section into a mixture channel and an air channel. The wall section has a recess in which the throttle flap at least partially lies in an end position. The wall section has, upstream of the recess, a continuous surface facing the mixture channel and which has lateral sections adjacent to the channel wall and a middle section running between the lateral sections. The lateral sections have, upstream of the throttle flap, a separation edge for the flow. In the end position, the side of the throttle flap facing the mixture channel defines a reference plane which divides the unit into a first region and a second region. The lateral sections extend, at least directly upstream of the recess, into the second region.

Fuel feed unit and two-stroke engine having a fuel feed unit

A carburetor has a housing wherein a control drum is rotatably mounted. A section of an intake channel is formed in the carburetor. A subsection of this section is formed in the control drum. The control drum controls the free flow cross section of the intake channel. A fuel opening is connected to a fuel chamber via an unbranched fuel channel which opens into the subsection of the intake channel. A simple configuration of the carburetor is achieved by the carburetor including an electrically actuated valve which controls the flow of fuel through the fuel channel. For a method for operating an internal combustion engine with a carburetor, a temperature (T) is determined before or during the starting of the engine and that the flow of fuel through the fuel channel during the starting of the engine is controlled in dependence upon the temperature (T).

Carburetor and method for operating an internal combustion engine having said carburetor

A two-stroke engine has an intake arrangement including a carburetor. An intake channel divides into a mixture channel and an air channel. An intermediate flange is mounted between the carburetor and the cylinder. This flange has a carburetor connecting surface, which faces toward the carburetor, and a cylinder connecting surface which faces toward the cylinder. Referred to the flow direction in the intake channel, the air channel divides upstream of the cylinder connecting surface into two branches. The first branch has a first longitudinal center axis and the second branch has a second longitudinal center axis. The intersect points of the center axes with the connecting surfaces are mutually connected via an imaginary connecting line in the carburetor connecting surface or the cylinder connecting surface. The two connecting lines conjointly define an angle &#x3b2; in the carburetor connecting surface with this angle being greater than 0&#xb0;.

Two-stroke engine having an intake arrangement

An internal combustion engine having an intake channel that is divided by a partition into an air duct and a mixture duct. The partition has a connecting opening that at least at full throttle of the internal combustion engine is substantially closed. A main fuel opening opens out into the mixture duct. At least one further fuel opening is provided that opens out into the mixture duct at a first distance relative to the wall of the intake channel and at a second distance relative to the partition.

Internal combustion engine

A work apparatus such as a blower apparatus () or a spray apparatus () has a drive motor (), a blower wheel () and a blower tube (). The blower wheel () is driven by the drive motor () and moves a flow of air through the blower tube (). The work apparatus () has a back carrier () on which the drive motor () is mounted. In order to avoid electrostatic charges during operation, the back carrier () has an arrangement which establishes an electrically conductive connection between the work apparatus () and the operator () of the work apparatus () during operation thereof.

Work apparatus

A portable spray apparatus () is provided to selectively discharge liquid spray medium and solid dust medium with a blower airflow () generated by a blower (). An adaptor () is provided which has at least a channel section () of a liquids channel () for the liquid spray medium and a channel section () of a solids channel () for the solid dust medium. The adaptor () is releasably connected to a supply vessel (). The liquids channel () and the solids channel () open into the blower airflow (). Various built-in positions of the supply vessel () and of the adaptor () are freely selectable relative to each other and to the blower unit () by the operator. In one built-in position, the liquids channel () is connected via its channel section () to an interior space () of the supply vessel () and, in another built-in position, the solids channel () is connected to this interior space () via the channel section () thereof.

Portable spray apparatus

A portable sprayer having a backpack to which are secured a blower unit and a supply tank. The blower unit includes a drive motor and a blower driven thereby. The blower unit is mounted on the backpack by at least one anti-vibration element. The supply tank, for example for spray agent, is mechanically separated from the blower unit and is also mounted on the backpack by at least one anti-vibration element. A removable, at least approximately rigid connection element is provided for coupling the supply tank and the blower unit together or for isolating them from one another with respect to vibrations.

Portable sprayer

A carburetor including a mixture channel and an air channel that are separated from one another, wherein a fuel opening opens into the mixture channel. A throttle element is rotatable about an axis of rotation that extends transverse of the direction of flow in the mixture channel and in the air channel and extends through both channels. As a function of its position, the throttle element throttles a flow cross-section of the mixture channel and the air channel. The flow cross-section of a portion of the mixture channel and/or of the air channel has a non-circular shape in the vicinity of the throttle element.

Carburetor

A connector between a carburetor and a cylinder connection of an internal combustion engine of an implement is provided. The flow channel formed in the connector is provided with raised portions over the inner periphery of the channel. To avoid fluctuations in the speed of the engine as a function of changes in position of the implement, the raised portions are embodied as wall portions that are oriented approximately transverse to the center line of the channel. The wall portions provide a flow cross-section for the channel that varies in a step-shape or terrace-shaped manner.

Connector between a carburetor and a cylinder of an internal combustion engine

An internal combustion engine, for example a two-stroke engine having scavenging collection, is provided. The combustion chamber formed in the cylinder is delimited by a reciprocating piston. A fuel/air mixture prepared in the Venturi section of a diaphragm carburetor is supplied to the engine. The air portion of the mixture is conveyed to the Venturi section via an intake channel, and the fuel portion is conveyed to the Venturi section via a main nozzle path that branches off from a fuel-filled control chamber to which fuel is supplied via a fuel line and a feed valve that is controlled by a control diaphragm that delimits the control chamber. A device is provided for varying the air portion and/or the fuel portion at full load. Connected to the device is a control unit that receives, as an input variable, an operating parameter of the engine that varies as a function of engine speed. The device is actuated as a function of the output signal of the control unit.

Internal combustion engine having adjustable CO characteristic curve

The invention relates to a two-stroke engine for a portable handheld work apparatus such as a motor-driven chain saw, cutoff machine, brushcutter or the like. A crankcase ( ) is formed below the engine cylinder ( ). A piston ( ) moves up and down in the cylinder ( ) and drives a crankshaft ( ) rotatably journalled in the crankcase ( ). A fuel-containing mixture is supplied via a membrane carburetor ( ) to the combustion chamber ( ) delimited between the piston ( ) and the cylinder ( ). A bypass channel ( ) is provided parallel thereto and supplies essentially fuel-free air to the combustion chamber ( ). The bypass channel ( ) opens into a channel segment ( ) via a connecting piece ( ) fixedly attached to the cylinder ( ). The channel segment ( ) is formed in the cylinder wall ( ). A spark plug ( ) and an ignition control device ( ) are assigned to the combustion chamber ( ). The ignition control device ( ) is fixedly mounted with a portion to the cylinder ( ) via one attachment point ( ) and is fixedly mounted to the connecting piece ( ) via another attachment point ( ).

Two-stroke engine

A cylinder is produced of die cast metal and is for a two-stroke engine in a portable handheld work apparatus such as a motor chain saw. A combustion chamber ( ) is formed in the cylinder ( ) and this combustion chamber is delimited by a piston ( ). In the cylinder wall ( ), there is an outlet ( ) for conducting away the combustion gases from the combustion chamber ( ). Transfer channels ( ) are provided which open into the combustion chamber ( ) via transfer windows ( ) and supply the operating medium from the crankcase ( ) needed for operating the two-stroke engine. The transfer channels ( ) are configured in the cylinder wall ( ) as channels opening radially to the outside and are closed by a seated cover ( ).

Die cast metal cylinder assembly for a two-stroke engine

The invention relates to a two-stroke engine in a portable handheld work apparatus such as a motor chain saw. A combustion chamber ( ) is formed in a cylinder ( ) and is delimited by a piston ( ). The piston ( ) drives a crankshaft ( ) via a connecting rod ( ). The crankshaft is journalled in a crankcase ( ). Air is supplied to the combustion chamber ( ) via a first outlet-near transfer channel ( ); whereas, the air/fuel mixture, which is needed for operation, flows in via a second outlet-remote transfer channel ( ) from the crankcase ( ). The constructive volume of the outlet-near transfer channel ( ) is designed to be approximately 20% to 60% of the volumetric total air input of the engine ( ) in order to achieve a complete charge of the combustion chamber while having low scavenging losses.

The invention relates to a two-stroke engine in a portable handheld work apparatus. A combustion chamber ( ) is formed in a cylinder ( ) and the chamber is delimited by a piston ( ). At least one transfer channel ( ) is provided which connects the crankcase ( ) to the combustion chamber ( ). An air channel ( ) opens into the transfer channel ( ) and this channel supplies essentially fuel-free gas, preferably air. The intake channel ( ) of a carburetor ( ) is connected to an intake opening ( ) in the housing base ( ) of the air filter housing ( ) upstream of a carburetor throttle flap. The intake channel ( ) connects downstream of the carburetor throttle flap to an intake channel ( ) to the crankcase ( ). To provide an ignition-ready mixture in order to start and run up the engine, it is provided that the air channel ( ) is connected to a bypass opening ( ) in the housing base ( ) of the air filter ( ) and a common pivotable choke element ( ) is assigned to the intake opening ( ) as well as the bypass opening ( ). The choke element ( ) clears the openings ( ) in the operating position and closes the passthrough cross section of the bypass opening ( ) in the start position whereas the passthrough cross section of the intake opening ( ) is reduced to a start cross section.

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Fellbach, Germany

Michael Raffenberg