摘要:
A method for operating an internal combustion engine having a fuel system which feeds fuel at a given pressure to a metering valve provides that a controller defines the opening time and the closing time of the metering valve and correspondingly actuates the metering valve so that the metering valve opens and closes at the defined times. In order to permit precise metering of fuel even in high-speed internal combustion engines there is provision for the controller to define at least one of the times for the opening or closing of the metering valve while taking into account the counterpressure actually prevailing at the outlet opening of the metering valve.
摘要:
A method for operating an internal combustion engine having a fuel system which feeds fuel at a given pressure to a metering valve provides that a controller defines the opening time and the closing time of the metering valve and correspondingly actuates the metering valve so that the metering valve opens and closes at the defined times. In order to permit precise metering of fuel even in high-speed internal combustion engines there is provision for the controller to define at least one of the times for the opening or closing of the metering valve while taking into account the counterpressure actually prevailing at the outlet opening of the metering valve.
摘要:
The absolute crankshaft angle of an internal combustion engine of a hand-held power tool is to be determined. The engine has a cylinder with a combustion chamber delimited by a piston that drives a crankshaft in a crankcase. The crankcase is connected by a transfer passage to the combustion chamber and the transfer port of the transfer passage is piston-controlled. Ignition takes place at an adjusted crankshaft angle. The energy supply unit of the engine is driven by the crankshaft and provides electric energy for ignition. The crankshaft angle is determined in that a signal generator is provided as an energy supply unit and generates an alternating voltage signal caused by a crankshaft revolution. An operating pressure signal of the engine is detected by a pressure sensor. The output signals of the pressure sensor and of the signal generator are linked with one another for determining the absolute crankshaft angle.
摘要:
The absolute crankshaft angle of an internal combustion engine of a hand-held power tool is to be determined. The engine has a cylinder with a combustion chamber delimited by a piston that drives a crankshaft in a crankcase. The crankcase is connected by a transfer passage to the combustion chamber and the transfer port of the transfer passage is piston-controlled. Ignition takes place at an adjusted crankshaft angle. The energy supply unit of the engine is driven by the crankshaft and provides electric energy for ignition. The crankshaft angle is determined in that a signal generator is provided as an energy supply unit and generates an alternating voltage signal caused by a crankshaft revolution. An operating pressure signal of the engine is detected by a pressure sensor. The output signals of the pressure sensor and of the signal generator are linked with one another for determining the absolute crankshaft angle.
摘要:
In a method for priming a fuel metering device for an internal combustion engine with a piston arranged in a combustion chamber and driving a crankshaft that is rotatably supported in a crankcase, with a fuel pump that conveys fuel from a fuel tank to a metering valve that opens into a metering chamber at alternating operating pressure, and with a control unit that calculates and controls timing for the metering valve for metering a fuel quantity corresponding to a load situation of the internal combustion engine, the metering valve is kept open, independent of the calculated timing for the metering valve, for a priming duration in a starting phase of the internal combustion engine when the alternating operating pressure of the metering chamber at the mouth of the metering valve is negative and when a fuel system pressure in the fuel metering device is below a target pressure.
摘要:
A hand-guided work apparatus includes a combustion engine to drive a work tool. The combustion engine includes a crankcase (14) in which a crankshaft (16) is rotatably mounted about a rotational axis (44). A pressure sensor (27) and a temperature sensor (26) are arranged on the crankcase (14). The pressure sensor (27) and the temperature sensor (26) are arranged in a common sensor housing (31). In the typical put-down position (8) of the work apparatus, the pressure sensor (27) and the temperature sensor (26) are arranged below a plane (45) which is parallel to the horizontal storage surface (7) and contains the rotational axis (44) of the crankshaft (16). A connecting channel (25) is formed in the sensor housing (31). The connecting channel (25) connects the pressure sensor (27) to the crankcase interior (20) and the base (35) of the connecting channel (25) slopes down toward the crankcase interior (20) in the typical put-down position (8) of the work apparatus.
摘要:
A hand-guided work apparatus includes a combustion engine to drive a work tool. The combustion engine includes a crankcase (14) in which a crankshaft (16) is rotatably mounted about a rotational axis (44). A pressure sensor (27) and a temperature sensor (26) are arranged on the crankcase (14). The pressure sensor (27) and the temperature sensor (26) are arranged in a common sensor housing (31). In the typical put-down position (8) of the work apparatus, the pressure sensor (27) and the temperature sensor (26) are arranged below a plane (45) which is parallel to the horizontal storage surface (7) and contains the rotational axis (44) of the crankshaft (16). A connecting channel (25) is formed in the sensor housing (31). The connecting channel (25) connects the pressure sensor (27) to the crankcase interior (20) and the base (35) of the connecting channel (25) slopes down toward the crankcase interior (20) in the typical put-down position (8) of the work apparatus.
摘要:
In a method for priming a fuel metering device for an internal combustion engine with a piston arranged in a combustion chamber and driving a crankshaft that is rotatably supported in a crankcase, with a fuel pump that conveys fuel from a fuel tank to a metering valve that opens into a metering chamber at alternating operating pressure, and with a control unit that calculates and controls timing for the metering valve for metering a fuel quantity corresponding to a load situation of the internal combustion engine, the metering valve is kept open, independent of the calculated timing for the metering valve, for a priming duration in a starting phase of the internal combustion engine when the alternating operating pressure of the metering chamber at the mouth of the metering valve is negative and when a fuel system pressure in the fuel metering device is below a target pressure.
摘要:
A method for leak-testing a fuel supply system has been provided, wherein the fuel supply system comprises a fuel tank, a fuel injection valve, fuel lines between the fuel tank and the fuel valve, and a control valve controlled by a diaphragm, and wherein the diaphragm bounds a control chamber on one side, the method comprising: acting upon the portion of the fuel supply system upstream of the control valve with a predetermined pressure level, acting upon the side of the diaphragm facing away from the control chamber with a counterforce, wherein the counterforce is equal or greater to the predetermined pressure level. A device for leak-testing a fuel system according to the above method, wherein the device comprises a test pressure unit with at least one test pressure line, wherein said test pressure line is connectable to the fuel supply system.
摘要:
A carburetor for an internal combustion engine includes an intake channel section (2) as well as a throttle element journalled in the intake channel section (2). The throttle element is adjustable between a full-load position (25) and an idle position (26). A pump (20, 30) is provided for additional fuel metering and this pump includes a pumping chamber (24, 34) and a pump piston (21, 31) guided in the pumping chamber (24, 34). The position of the pump piston (21, 31) is coupled to the position of the throttle element. To ensure an optimal supply of the internal combustion engine with fuel in each operating state, the pump piston (21, 31) is so coupled to the throttle element that fuel is pumped from the pumping chamber (24, 34) into the intake channel section (2) when there is a displacement of the throttle element from the full throttle position (25) into the idle position (26).