Andreas Stihl Ag Co. Kg

Niels Kunert

Florian Hoche

Michael Grether

Horst Denner

Werner Geyer

Heiko Rosskamp

Klaus Geyer

Tommy Roitsch

André Prager

Michael Dietenberger

Johannes Alber

Martin Christoph Arenz

Hans Hildenbrand

Marcus Bonifer

Jürgen Aupperle

Markus Maurer

Dietmar Widmann

Jan-Eilert Kueper

Jan-Eilert KÜPER

An exhaust muffler has an exhaust inlet, an exhaust outlet, as well as a catalytic converter which, in the flow direction, is disposed between the exhaust inlet and the exhaust outlet. The catalytic converter has at least one throughflow body which includes at least one wire body. At least one first component region of the throughflow body is coated with a catalytically functioning coating. The throughflow body moreover has a second component region which in terms of volume has a smaller quantity of catalytically functioning coating than the first component region.

Exhaust muffler, two-stroke engine or four-stroke engine having an exhaust muffler, and catalytic converter for an exhaust muffler

A working apparatus has an internal combustion engine which drives at least one tool via a clutch. The clutch starts the coupling process at an initial engagement speed when the internal combustion engine is accelerated. The internal combustion engine has a piston, an ignition device and an ignition timing control device. The control device provides a first ignition timing for idling and a second ignition timing for full load operation, which is earlier than the first ignition timing. A method for operating the working apparatus provides that the ignition timing is adjusted toward 'late,' with respect to the first ignition timing, when the engine speed drops in a first speed range above the idling speed and below the initial engagement speed.

Working apparatus and a method for operating same

A two stroke engine comprises a cylinder, in which a combustion chamber bounded by a piston is formed, and an intake passage. A carburetor forms a section of the intake passage, within which a throttle element is mounted pivotably, and at least one main fuel opening and at least one idling fuel opening open into the intake passage, which is divided downstream of the carburetor into an air passage and a mixture passage. The idling fuel opening feeds a secondary passage arranged within the mixture passage. In the idling position, the throttle element may be arranged adjacent to the upstream entry opening in the secondary passage, and the throttle element may have an opening which, in the idling position of the throttle element, is arranged in the region of the entry opening and connects the secondary passage to that region of the intake passage located upstream of the throttle element.

Two-stroke engine

A two-stroke engine has a cylinder having a cylinder bore with a combustion chamber and an outlet connected with the combustion chamber. A piston is disposed in the cylinder and delimits the combustion chamber. The piston has a piston recess. A crankcase is provided that has a crankshaft rotatably supported therein. The piston drives in rotation the crankshaft. In at least one position of the piston, the crankcase is connected by a transfer passage with the combustion chamber. An air passage is provided as well as a mixture passage that has a mixture inlet that is disposed at the cylinder bore and opens into the cylinder bore and is piston-controlled. The transfer passage is connected by the piston recess to the air passage when the piston is at top dead center. The piston recess has a connection to the mixture inlet in at least one position of the piston.

A hand-held power tool has a two-stroke engine with a cylinder with combustion chamber and a piston disposed therein that drives a crankshaft supported in a crankcase. In at least one piston position, crankcase and combustion chamber are connected by a transfer passage. An air passage supplies in at least one piston position combustion air to the transfer passage. A mixture passage for fuel/air mixture is provided. Air and mixture passages in operation are at least partially connected to each other. Part of the mixture passage is formed in a carburetor where a fuel port opens into the mixture passage. The mixture passage opens into the crankcase with a piston-controlled mixture inlet having a width in circumferential direction of the cylinder. Upon upward piston stroke the mixture inlet is connected to the crankcase with a portion of the width before a connection of air passage and transfer passage is established.

Hand-held power tool

An internal combustion engine has a cylinder () wherein a combustion chamber () is formed which is delimited by a piston () journalled to move back and forth. At least one transfer channel () is provided which connects the crankcase () of the engine to the combustion chamber () in at least one position of the piston (). The engine has a supply channel () which opens with a supply channel inlet () at the cylinder bore (). The supply channel () is connected to the transfer channel () via at least one piston pocket () in at least one position of the piston (). In order to achieve low exhaust-gas values of the engine, the piston pocket () has a distance (a) to a lower edge () of the transfer window () which is less than the distance (b) to a lower edge () of the inlet () of the supply channel at bottom dead center of the piston (). A method for operating an engine provides that the piston pocket () is first connected to the transfer window () and then to the supply channel inlet () during the upward stroke of the piston ().

Internal combustion engine and method of operating the same

A cylinder for a two-stroke engine has a cylinder wall defining a cylinder interior. A cylinder head closes of a combustion chamber in the cylinder interior. An exhaust is connected to the cylinder interior. At least one transfer passage having a transfer port opens into the cylinder interior. The at least one transfer passage is disposed in the cylinder wall for connecting a crank case of the two-stroke engine to the combustion chamber. The at least one transfer passage has at the level of the transfer port at least one flow deflecting rib having a radial spacing from the transfer port in a radial outward direction relative to a longitudinal cylinder axis.

Cylinder for a two stroke engine

A two-stroke engine includes an air channel for supplying substantially fuel-free combustion air and a mixture channel for supplying an air/fuel mixture. The air channel and the mixture channel connect the cylinder of the two-stroke engine to an air filter. A section of the mixture channel and a section of the air channel are guided in a common component. In order to prevent induction of mixture into the air channel, the length (a) of the mixture channel and the length (b) of the air channel are so matched to each other that the pressure wave in the air channel, which forms during operation, oscillates in phase with the pressure wave formed in the mixture channel. The length (a) of the mixture channel is matched to an optimal fuel induction via the fuel opening. A method for tuning the two-stroke engine provides that the length (a) of the mixture channel is matched to an optimal fuel discharge from the fuel opening in a first step and, in a second step, the length (b) of the air channel is so matched to the length (a) of the mixture channel that the pressure wave in the air channel and the pressure wave in the mixture channel oscillate in phase during operation of the two-stroke engine.

Two-stroke engine assembly

A cylinder for an internal combustion engine of a manually guided implement, and a method of producing such a cylinder, are provided. A cast cylinder body that peripherally delineates a cylinder chamber has formed therein at least one transfer channel that is open inwardly into the cylinder chamber and includes a central portion, extending approximately parallel to the cylinder axis, and a head portion that above the central portion faces in the direction of the cylinder chamber. A cylindrical sleeve covers the central portion of the transfer channel inwardly in the direction of the chamber. The sleeve extends in the direction of the cylinder axis beyond the central portion and ends below the head portion.

Cylinder for an internal combustion engine of a manually guided implement

An intake arrangement for an internal combustion engine includes an intake channel () which connects the clean side () of an air filter () to the engine. The intake channel () is subdivided by a partition wall () into an air channel () and a mixture channel (). A throttle flap is mounted in the intake channel (). A fuel opening () for supplying fuel opens into the mixture channel (). In order to avoid a throw back of fuel from the mixture channel () into the air channel (), it is provided that the clean side () of the air filter () is divided into two chambers (and) and the mixture channel () opens into the first chamber () and the air channel () opens into the second chamber ().

Growing community of inventors

Ottenbach, Germany

Niels Kunert