摘要:
An ignition circuit is for an internal combustion engine in a handheld portable work apparatus. A combustion chamber (4) is configured in the cylinder (3) of the engine (1) which is delimited by a piston (5) driving a crankshaft (7). An electromagnetic induction loop (13) and a pole wheel (10) are provided. The pole wheel (10) revolves with the crankshaft (7) and is assigned to the induction loop (13). The pole wheel (10) periodically changes the magnetic flux in the induction loop (13). An ignition capacitor (16) is charged by a charge coil (14) of the induction loop (13) and is discharged via a discharge circuit (15) via an ignition coil (17). The ignition coil (17) is connected to a spark plug (19) projecting into the combustion chamber (4). For achieving a powerful ignition spark, the discharge of the ignition capacitor (16) is prevented by an rpm evaluation circuit (23) when the rpm curve (30) exhibits an rpm change (Δn) which exceeds a pregiven threshold value.
摘要:
The invention is directed to a method for operating a two-stroke engine having a cylinder in which a combustion chamber is formed and which includes devices for metering fuel and supplying combustion air as well as an ignition device for igniting a mixture in the combustion chamber. In the method, fuel and combustion air are supplied to the engine and the mixture in the combustion chamber is ignited. The combustion chamber is delimited by a piston which drives a crankshaft rotatably journalled in a crankcase. A control is provided which controls the metering of fuel and the ignition of the mixture in the combustion chamber. In the method, the two-stroke engine is controlled in at least one operating state so that the number of combustions is less than the number of revolutions of the crankshaft in the same time interval.
摘要:
The invention is directed to a method for operating a two-stroke engine having a cylinder in which a combustion chamber is formed and which includes devices for metering fuel and supplying combustion air as well as an ignition device for igniting a mixture in the combustion chamber. In the method, fuel and combustion air are supplied to the engine and the mixture in the combustion chamber is ignited. The combustion chamber is delimited by a piston which drives a crankshaft rotatably journalled in a crankcase. A control is provided which controls the metering of fuel and the ignition of the mixture in the combustion chamber. In the method, the two-stroke engine is controlled in at least one operating state so that the number of combustions is less than the number of revolutions of the crankshaft in the same time interval.
摘要:
An ignition circuit is for an internal combustion engine in a handheld portable work apparatus. A combustion chamber (4) is configured in the cylinder (3) of the engine (1) which is delimited by a piston (5) driving a crankshaft (7). A pole wheel (10) revolves with the crankshaft (7) and is assigned to an induction loop (13). The pole wheel periodically changes the magnetic flux in the induction loop. An ignition capacitor (16) is charged by a charge coil (14) of the induction loop and is discharged via a discharge circuit (15) via an ignition coil (17). The ignition coil is connected to a spark plug (19) projecting into the combustion chamber. For achieving a powerful ignition spark, the discharge of the ignition capacitor is prevented by an rpm evaluation circuit (23) when the rpm curve (30) exhibits an rpm change (Δn) which exceeds a pregiven threshold value.
摘要:
The invention relates to a two-cycle engine for a drive engine in a portable, manually operated tool. The combustion chamber formed in a cylinder is delimited by a piston that moves up and down, whereby the piston, by means of a connecting rod, drives a crankshaft rotatably mounted in a crankcase. The combustion chamber has an outlet for removing waste gases, and provided for supplying a fuel/air mixture prepared by a mixture preparation device, and combustion air, are gas-supplying channels that open into the combustion chamber. In order to reduce scavenging losses, it is provided that for the entire duration of the gas exchange exclusively air flows in the area near the outlet and exclusively fuel/air mixture flows out of the crankcase in the area further away from the outlet.
摘要:
In a method for operating an internal combustion engine, wherein the internal combustion engine has a cylinder in which a combustion chamber is provided that is delimited by a reciprocating piston guided in the cylinder, wherein the piston is connected by a connecting rod to a crankshaft and wherein the internal combustion engine has a device for supplying fuel and a device for igniting the fuel/air mixture in the combustion chamber at least one engine speed value of the internal combustion engine is determined and evaluated. A pre-ignition state of the internal combustion engine is determined based on the result of the evaluation step.
摘要:
An arrangement for decanting liquids includes a tubular-shaped support (1) having a flow channel (2). The flow channel (2) is blocked by a valve plate (3) which is coupled via axial connecting elements (4, 4′) to the relative movement of an inner sleeve (5) and an outer sleeve (6) of the support (1). The outer sleeve (6) lies in overlapment and the axial connecting elements (4, 4′) extend into the interior of the support. The valve plate (3) can be lifted from its valve seat against a spring force engaging at the inner sleeve (5) and at the outer sleeve (6). A radial flange collar (13) is formed on the outer sleeve (6). To ensure an accurate metering at the highest possible volume flow of the discharged liquid at low manufacturing costs, the valve plate (3) is mounted at a free end (9) of the support (1) and the axial connecting elements are configured as tension rods (4, 4′) and are arranged next to an edge of the valve plate (3).
摘要:
A portable handheld work apparatus such as a motor-driven chain saw (1) includes a housing (2) wherein an internal combustion engine (10) and a carburetor (11) are mounted. A throttle lever (6) is provided which is pivotally journalled on a handle (3). The handle (3) is connected to the housing (2) via at least one antivibration element (33). A vibration gap (9) is configured between the handle (3) and the housing (2). A transmitting unit (13) is provided for transmitting the pivot movement of the throttle lever (6) to the carburetor (11). The transmitting unit includes a rigid transmitting element (17, 37) which bridges the vibration gap (9). A simple configuration and a substantial decoupling of the relative movement between the housing (2) and the handle (3) from the actuating movement of the carburetor is achieved in that the transmitting element (17, 37) is rotatably journalled and the pivot movement of the throttle lever (6) is transmitted as a rotation about a rotational axis (22) lying transverse to the vibration gap (9).
摘要:
The invention relates to a carburetor arrangement for an internal combustion engine (1), especially for a drive motor of a work apparatus such as a motor-driven chain saw, a brushcutter, a cutoff machine or the like. The carburetor arrangement includes a carburetor (2) having an intake channel (3) and an air filter (4) mounted upstream of the intake channel (3). The air filter (4) has an air filter housing (5). The intake channel (3) opens with an intake opening (6) in a housing base (7) of the air filter housing (5). The intake opening (6) can be covered at least partially by a choke element (8). The choke element (8) is held on a choke carrier (9) so as to permit a limited movement of the choke element.
摘要:
The invention is directed to a tensioning arrangement for saw chains of motor-driven chain saws which include a device for longitudinally displacing the guide bar. The clamped guide bar is released so that the adjusting arrangement can be actuated for the longitudinal displacement of the guide bar. By rotating a disc having a spiral slot, a slide piece, which is coupled to the guide bar, is displaced in the longitudinal direction. Assembly is simplified and handling facilitated when the tension in the saw chain is adjusted. This is achieved by making the slide piece on the spiral disc so that it is not released therefrom but instead is held so as to be rotationally and longitudinally displaceable. The slide piece is fixedly connected to the guide bar by using appropriate attachment devices.