An internal combustion engine having an engine control configured to operate in first and second operating modes. The first operating mode is configured to leave as many ignition devices deactivated per cycle in dependence on the currently present power demand. The second operating mode is configured to reduce a risk of deflagration due to unburned gas-air mixture present in an exhaust stroke. After a first number (N.sub.1) of cycles, for a second number (N.sub.2) of cycles, the second operating mode has more piston-cylinder units produce power per cycle than required for the currently present power demand. After the second number (N.sub.2) of cycles, for a third number (N.sub.3) of cycles, in dependence on a currently present power demand per cycle, the second operating mode has so many piston-cylinder units produce power that this results in a torque of the crankshaft adapted to the currently present power demand.

An internal combustion engine (1) operating in cycles, having: a plurality of piston-cylinder units (2), wherein each piston-cylinder unit (2) of the plurality of piston-cylinder units (2) is assigned an ignition device (3) which can be controlled regarding activation and selection of an ignition timing by an engine control (4), wherein a piston-cylinder unit (2), when the ignition device (3) is activated, produces a power by combustion of a gas-air mixture, which can be transmitted as a torque to a crankshaft (5) of the internal combustion engine (1) an intake stroke (6) and an exhaust stroke (7), each coupled to the plurality of piston-cylinder units (2) a supply device (8) for supplying a gas-air mixture under a boost pressure to the intake stroke (6) a signal detection device (9) for acquiring at least one signal which represents a power demand on the internal combustion engine (1) or from which a power demand on the internal combustion engine (1) can be calculated an engine control (4) for actuating actuators of the internal combustion engine (1), wherein the at least one signal can be fed to the engine control (4), and the engine control (4) is configured in a first operating mode to leave as many ignition devices (8) deactivated per cycle of the internal combustion engine in dependence on the currently present power demand, that the power of those piston-cylinder units (2), the ignition devices (8) of which are activated, results in a torque of the crankshaft (5) of the internal combustion engine (1) adapted to the currently present power demand
wherein the engine control (4) is configured to, in a second operating mode, for reducing a risk of deflagration due to unburned gas-air mixture present in the exhaust stroke (7) after a first number (N.sub.1) of cycles of the internal combustion engine (1), for a second number (N.sub.2) of cycles of the internal combustion engine (1), to have more piston-cylinder units (2) produce power per cycle by activating the assigned ignition devices (8) than would be required for the currently present power demand after the second number (N.sub.2) of cycles of the internal combustion engine (1), for a third number (N.sub.3) of cycles of the internal combustion engine (1), in dependence on a currently present power demand per cycle of the internal combustion engine (1), to have so many piston-cylinder units (2) produce power by activation of the assigned ignit

A handheld work apparatus has a combustion engine (4) for driving a tool. The combustion engine (4) has an ignition device, a device for metering fuel and a control device (31). The control device (31) engages when an engagement speed (n.sub.E1, n.sub.E2) is reached, in order to limit the speed (n) of the combustion engine (4). In order to allow the speed (n) to be set in an easy manner at full throttle, the work apparatus has a device for setting the engagement speed (n.sub.E2) by the user.

In a general aspect, an apparatus can include an insulated-gate bipolar transistor device (IGBT), a gate driver circuit (driver) coupled with a gate terminal of the IGBT and a low-resistance switch device coupled between an emitter terminal of the IGBT and an electrical ground terminal, the low-resistance switch device being coupled with the electrical ground terminal via a resistor. The apparatus can also include a current sensing circuit coupled with the driver and a current sense signal line coupled with the current sensing circuit and a current sense node, the current sense node being disposed between the low-resistance switch device and the resistor. The apparatus can further include a control circuit configured, when the driver is off, to detect, based on a voltage on the current sense node, when a current through the resistor is above a threshold value and disable the IGBT in response to the detection.

An electric starting system for an internal combustion engine is provided. The starting system includes a battery, a starter motor, and a blower housing. The starter motor is configured to start the internal combustion engine. The battery is integrated with the blower housing.

An internal combustion engine (1) operating in cycles, having: a plurality of piston-cylinder units (2), wherein each piston-cylinder unit (2) of the plurality of piston-cylinder units (2) is assigned an ignition device (3) which can be controlled regarding activation and selection of an ignition timing by an engine control (4), wherein a piston-cylinder unit (2), when the ignition device (3) is activated, produces a power by combustion of a gas-air mixture, which can be transmitted as a torque to a crankshaft (5) of the internal combustion engine (1) an intake stroke (6) and an exhaust stroke (7), each coupled to the plurality of piston-cylinder units (2) a supply device (8) for supplying a gas-air mixture under a boost pressure to the intake stroke (6) a signal detection device (9) for acquiring at least one signal which represents a power demand on the internal combustion engine (1) or from which a power demand on the internal combustion engine (1) can be calculated an engine control (4) for actuating actuators of the internal combustion engine (1), wherein the at least one signal can be fed to the engine control (4), and the engine control (4) is configured in a first operating mode to leave as many ignition devices (8) deactivated per cycle of the internal combustion engine in dependence on the currently present power demand, that the power of those piston-cylinder units (2), the ignition devices (8) of which are activated, results in a torque of the crankshaft (5) of the internal combustion engine (1) adapted to the currently present power demand
wherein the engine control (4) is configured to, in a second operating mode, for reducing a risk of deflagration due to unburned gas-air mixture present in the exhaust stroke (7) after a first number (N.sub.1) of cycles of the internal combustion engine (1), for a second number (N.sub.2) of cycles of the internal combustion engine (1), to have more piston-cylinder units (2) produce power per cycle by activating the assigned ignition devices (8) than would be required for the currently present power demand after the second number (N.sub.2) of cycles of the internal combustion engine (1), for a third number (N.sub.3) of cycles of the internal combustion engine (1), in dependence on a currently present power demand per cycle of the internal combustion engine (1), to have so many piston-cylinder units (2) produce power by activation of the assigned ignit

An internal combustion engine (1) operating in cycles, having: a plurality of piston-cylinder units (2), wherein each piston-cylinder unit (2) of the plurality of piston-cylinder units (2) is assigned an ignition device (3) which can be controlled regarding activation and selection of an ignition timing by an engine control (4), wherein a piston-cylinder unit (2), when the ignition device (3) is activated, produces a power by combustion of a gas-air mixture, which can be transmitted as a torque to a crankshaft (5) of the internal combustion engine (1) an intake stroke (6) and an exhaust stroke (7), each coupled to the plurality of piston-cylinder units (2) a supply device (8) for supplying a gas-air mixture under a boost pressure to the intake stroke (6) a signal detection device (9) for acquiring at least one signal which represents a power demand on the internal combustion engine (1) or from which a power demand on the internal combustion engine (1) can be calculated an engine control (4) for actuating actuators of the internal combustion engine (1), wherein the at least one signal can be fed to the engine control (4), and the engine control (4) is configured in a first operating mode to leave as many ignition devices (8) deactivated per cycle of the internal combustion engine in dependence on the currently present power demand, that the power of those piston-cylinder units (2), the ignition devices (8) of which are activated, results in a torque of the crankshaft (5) of the internal combustion engine (1) adapted to the currently present power demand
wherein the engine control (4) is configured to, in a second operating mode, for reducing a risk of deflagration due to unburned gas-air mixture present in the exhaust stroke (7) after a first number (N.sub.1) of cycles of the internal combustion engine (1), for a second number (N.sub.2) of cycles of the internal combustion engine (1), to have more piston-cylinder units (2) produce power per cycle by activating the assigned ignition devices (8) than would be required for the currently present power demand after the second number (N.sub.2) of cycles of the internal combustion engine (1), for a third number (N.sub.3) of cycles of the internal combustion engine (1), in dependence on a currently present power demand per cycle of the internal combustion engine (1), to have so many piston-cylinder units (2) produce power by activation of the assigned ignit

A two-stroke engine (4) has a throttle motor (22) for driving a throttle valve (20), a fuel injection device (430) disposed in an intake system (18) including a crank chamber (420), and a control unit (24) controlling the throttle motor (22) and the fuel injection device. The two-stroke engine (4) is designed to achieve an engine rotation speed of 4,500 rpm to 7,000 rpm when the throttle valve (20) is fully open. The two-stroke engine (4) is operated with the throttle full open by the control unit (24), and a battery (8) is charged with electric power generated by a generator (6) using the two-stroke engine.

A two-stroke engine (4) has a throttle motor (22) for driving a throttle valve (20), a fuel injection device (430) disposed in an intake system (18) including a crank chamber (420), and a control unit (24) controlling the throttle motor (22) and the fuel injection device. The two-stroke engine (4) is designed to achieve an engine rotation speed of 4,500 rpm to 7,000 rpm when the throttle valve (20) is fully open. The two-stroke engine (4) is operated with the throttle full open by the control unit (24), and a battery (8) is charged with electric power generated by a generator (6) using the two-stroke engine.

Various embodiments of the present technology comprise a method and apparatus for an ignition system. In various embodiments, the ignition system activates a soft shutdown of an ignition coil in the event of an over dwell condition. The apparatus comprises a first counter and a second counter that are selectively activated at predetermined events. An output of the second counter controls the value of a reference current that decreases linearly over time and wherein a rate of change of the reference current may be adjusted according to a frequency of a clock signal. In various embodiments, the soft shutdown operates independent of the supply voltage and temperature.