Andreas Stihl Ag Co. Kg

Firma Andreas Stihl Ag & Co.

Andreas Stihl Ag & Co.

Heinrich Leufen

Eberhard Schieber

Georg Maier

Mohamed Abou-Aly

Rolf Walter

Hans Nickel

Heiko Rosskamp

Jörg Schlossarczyk

Ernst Gorenflo

David Fallscheer

Jörg Präger

Gernot Liebhard

Roland Schierling

Claus Naegele

Wolfgang Layher

Klaus Geyer

Kay-Steffen Gurr

Kai-Ulrich Machens

Andreas Bähner

Andreas Neubauer

Andreas Lingen

Alexander Haas

Markus Herzog

Erik Andresen

Jens Kloeker

Fried Berkenkamp

Franz Mandl

Stanislaw Cichon

Markus Hüsges

Joerg Praeger

Ina Weimer

Alexander Klein

Michael Harrer

Michael Link

Leo Kieβling

Rainer Widmann

Philippe Buerckel

Jürgen Redecker

Simon Klaiber

Jochen Siller

Plilippe Bürckel

Jens Klöker

A hand-guided gardening, forestry and/or construction processing device includes a processing tool, an electric motor drive system, wherein the electric motor drive system is designed to drive the processing tool, a user-adjustable operating element, and a control device. The control device is designed to control a target slope rate of a rotational speed of the electric motor drive system in dependence on a position of the operating element according to at least one allocation in such a way that maximum target slope rates of the rotational speed differ for different positions.

Hand-guided gardening, forestry and/or construction processing device and method for operating a hand-guided gardening, forestry and/or construction processing device

An electric motor is connected to a voltage source via a drive circuit and, between the drive circuit and the voltage source, the operating switch is arranged for the switching of the supply voltage (U) of the voltage source as the input voltage (U) on the drive circuit. Following the switch-out of the electric motor, the input voltage (U) on the drive circuit is monitored and a gradient of a rising voltage ramp (dU/dt) of the input voltage (U) is determined. The gradient of the rising voltage ramp (dU/dt) of the input voltage (U) thus determined is compared with a predefined limiting value and, in the event of an overshoot of the predefined limiting value, the operating switch is detected as closed, and the electric motor is restarted via the drive circuit.

Method and apparatus for the detection of the position of an operating switch for starting an electric motor

In a power tool, an internal combustion engine is coupled by a clutch to a tool member. An ignition control device is provided that for each engine speed of the internal combustion engine specifies at least one ignition timing. For each engine speed of a first engine speed range a correlated first ignition timing is specified, wherein each first ignition timing is an ignition timing of a first ignition timing range. For each engine speed of a second engine speed range, adjoining the first engine speed range, a correlated second ignition timing is specified, wherein each second ignition timing is an ignition timing of a second ignition timing range. The first ignition timing is retarded by at least 5&#xb0; crank angle relative to the second ignition timing. The first engine speed range extends at least from the coupling engine speed range to the limit engine speed of approximately 7,000 RPM.

Method for operating an internal combustion engine of a hand-guided power tool

A portable, handheld work apparatus such as a chain saw has a handle () to guide the work apparatus () and has an air-cooled, mixture-lubricated combustion engine () arranged in a casing as a drive for a work tool (). The cylinder () has a combustion chamber () formed therein to which an air/fuel mixture is supplied. The air/fuel mixture is ignited by a spark plug () which projects into the combustion chamber (). An ignition control () triggers a spark in dependence on the angular position of the crankshaft (). A temperature sensor () is provided to control the cylinder temperature. The temperature signal of the temperature sensor () is connected to a power control (). When a predetermined temperature is exceeded, the power control () changes the operating parameters of the combustion engine () in such a manner that the power of the combustion engine () is changed.

Handheld work apparatus having an air-cooled combustion engine

In a method for providing in a hand-held power tool electric energy for an engine control unit before start of an internal combustion engine of the power tool that is to be started by a rope starter, a voltage source is provided that generates electric energy electro-dynamically or photovoltaically before starting the internal combustion engine. The thus generated electric energy is stored in a rechargeable energy storage device arranged within the power tool. The electric energy stored in the energy storage device is supplied to the engine control unit upon first rope starter pull for start of the internal combustion engine. The device for performing the method has an electro-dynamic or photovoltaic voltage source and an energy storage device electrically conductingly connected to the voltage source, wherein the energy storage device has an output that is electrically conductingly connected to the engine control unit.

Method and device for providing electric energy for an engine control unit

A portable work apparatus has a combustion engine for driving a work tool. An air/fuel mixture is supplied to the engine via a carburetor which is provided with an electrical heating element for heating to a given temperature. The heating element is connected to a switch via which electrical energy, which is provided by a generator driven by the engine, is supplied. When a given temperature is exceeded, the switch interrupts the energy supply. To achieve an exact temperature control, the ohmic resistance value of the heating element is stored in a memory in dependence on the temperature. The current flowing through the heating element and the voltage drop at the heating element are measured and the instantaneous resistance of the heating element is calculated therefrom. This calculated value is compared to the value stored in the memory to open or close the switch in dependence on the comparison.

Handheld work apparatus having a control unit for an electric heating element

A handheld work apparatus has a drive motor which drives a work tool and a generator. The work apparatus has a first electrical load and a connectable second electrical load. The generator provides the electrical power for the simultaneous operation of the two loads. The work apparatus has a control unit for controlling the power supplied to the first electrical load. In order to supply approximately the same power independent of voltage fluctuations, a voltage monitoring circuit is provided which, in a first operating state, sets a first signal sequence for operating the first load and, in a second operating state, sets a different second signal sequence for operating the first load. The mean power of the first signal sequence and that of the other second signal sequence are approximately equal.

Handheld work apparatus having a control unit for operating an electric load

The invention relates to a portable hand-guided work apparatus having an internal combustion engine () for driving a work tool (). A combustion chamber () is formed in a cylinder () of the engine () and is delimited by a piston () which drives a crankshaft () in rotation. A spark plug () is held in the cylinder () and is driven by an ignition module () to ignite a compressed air/fuel mixture in the combustion chamber () to drive the piston (). A short circuit line () is provided on the ignition module () for switching off the ignition. The short circuit line () is configured as a bus line () in order to make available, in a simple manner, a plurality of further operating parameters to the ignition module. An external control apparatus () and/or sensors () are connected to the bus line (). The ignition module (), as master, controls data traffic on the bus line () and permits a data communication on the bus line () only when a minimum crankshaft angular distance (A, B) is present at an ignition time point (Z, Z) of the ignition module ().

Ignition module having a bus line

In a method for detecting an operating parameter of a power tool having an internal combustion engine with a cylinder, a piston delimiting a combustion chamber in the cylinder and driving a crankshaft supported rotatably in a crankcase, an intake supplying combustion air to the combustion chamber, an exhaust removing combustion gases from the combustion chamber, and a signal generator driven in rotation by the crankshaft emitting sequential alternating voltage signals, a period duration of the voltage signal is selected to correspond to the n-th portion of a crankshaft revolution with n greater than 2. The n-th portion of the crankshaft revolution provides a crankshaft angle interval. For each crankshaft angle interval at least one information is detected that represents a course plotted against the crankshaft angle. The course is scanned with regard to characteristic features that are correlated with an operating parameter of the power tool.

Method for detecting operating parameters of a power tool comprising an internal combustion engine

A two-stroke engine has a cylinder with a combustion chamber delimited by a reciprocating piston, wherein the piston drives in rotation a crankshaft, and wherein a spark plug projects into the combustion chamber and ignites a fuel/air mixture. The two-stroke engine further has devices for supplying fuel and combustion air to the combustion chamber and a control unit that determines the ignition timing based on an ignition map. The ignition map indicates the ignition timing as a function of the engine speed for at least one first and one second operating states and for at least one first and one second engine speed ranges. The engine is controlled in that for an engine cycle the ignition timing is set in the second operating state at least within the first engine speed range based on the engine speed and on the number of engine cycles since the last combustion.

Method for operating a two-stroke engine

An internal combustion engine has a combustion chamber having a spark plug arranged thereat. A crankcase supports a crankshaft. An intake for introducing fuel and combustion air into the combustion chamber is provided. An exhaust for exhausting combustion gases from the combustion chamber is provided. A piston is connected to the crankshaft and drives the crankshaft in rotation. A wheel member is connected to the crankshaft and rotates with the crankshaft. An alternator driven by the crankshaft supplies electric power to a consumer. The alternator is arranged within a radial boundary of the wheel member and external to the crankcase. The alternator has a stator and a rotor, wherein the crankshaft penetrates the stator and wherein the rotor is fixedly connected to the wheel member.

Internal combustion engine with alternator

A hand-held power tool has a drive motor driving a tool and a generator. One or more heating devices having one or more heating elements are provided. The generator supplies the one or more heating devices with energy. A control device controls a power supplied to the one or more heating elements as a function of at least one operating parameter of the drive motor.

Hand-held power tool and method for operating a heating device of a hand-held power tool

A power tool has a drive unit arranged in a tool housing. The drive unit has an internal combustion engine with a cylinder provided with a combustion chamber. A spark plug is arranged at the cylinder. A piston is connected to a crankshaft and reciprocates within the cylinder and delimits the combustion chamber. A central control unit controls the drive unit and has a microprocessor and an ignition control unit, wherein the central control unit is connected by the ignition control unit to the spark plug and triggers a spark at the spark plug as a function of a rotary speed of the crankshaft at an appropriate ignition timing. A data storage device is connected to the central control unit. An energy supply unit provides electric energy. An interface enables, from outside the tool housing, external data access to data of the central control unit.

Portable hand-held power tool having a data connection for diagnostic purposes

A hand-held power tool has an electric drive motor having a drive shaft and a tool connected to the drive shaft and rotatably driven by the drive shaft. The drive motor has a control device that has correlated therewith at least a first operating curve and a second operating curve. The control device operates the electric drive motor in idle according to the first operating curve and operates the electric drive motor under load according to the second operating curve. The first operating curve covers the low power range at low speed and the second operating curve covers a large power range at high speed.

Hand-held power tool, in particular a trimmer or the like, having an electric drive motor

An ignition circuit is for an internal combustion engine in a handheld portable work apparatus. A combustion chamber () is configured in the cylinder () of the engine () which is delimited by a piston () driving a crankshaft (). A pole wheel () revolves with the crankshaft () and is assigned to an induction loop (). The pole wheel periodically changes the magnetic flux in the induction loop. An ignition capacitor () is charged by a charge coil () of the induction loop and is discharged via a discharge circuit () via an ignition coil (). The ignition coil is connected to a spark plug () projecting into the combustion chamber. For achieving a powerful ignition spark, the discharge of the ignition capacitor is prevented by an rpm evaluation circuit () when the rpm curve () exhibits an rpm change (&#x394;n) which exceeds a pregiven threshold value.

Ignition circuit having a high-energy spark for an internal combustion engine

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Schwaikheim, Germany

Heinrich Leufen