Abstract: A fuel system (10) serves to supply fuel (18) to an internal combustion engine. The fuel system includes a reservoir (16) and a first fuel pump (20) whose input is connected to the reservoir (16). In addition, a second fuel pump (38) is provided, whose input is connected to the first fuel pump (20). Furthermore, at least one injection valve (50) is provided, which is connected to the second fuel pump (38) and can supply fuel at least indirectly to a combustion chamber. A leakage line (68) is provided between the second fuel pump (38) and the reservoir (16). In order to permit a reliable hot start of the engine with a simultaneously low strain on the components, the invention proposes that the leakage line (68) be provided with a valve device (70), which has a shutoff function (72) and a pressure relief function (74) that are connected in parallel with each other.

Abstract: An injection system for internal combustion engines is proposed, in which once the engine has been turned off, a pressure equalization is established between the intake side and the pressure side of the high-pressure fuel pump. This prevents uncombusted fuel from reaching the combustion chambers of the engine. The pressure prevailing on the pressure side and the intake side when the engine is off furthermore assures that vapor bubbles cannot form, and this makes starting the engine easier.

Abstract: A fuel system for supplying fuel to an internal combustion engine includes a storage tank and a first fuel pump, which is connected on the input side to the storage tank. A second fuel pump is connected on the input side to the first fuel pump via a fuel connection. The system also includes a pressure adjusting device for the output side of the second fuel pump and a pressure damping device disposed in the fuel connection between the first fuel pump and the second fuel pump. Cost of the system is reduced by a flow inhibitor, which only permits a flow in the direction of the second fuel pump, disposed in the fuel connection between the first fuel pump and the second fuel pump, close to the second fuel pump and upstream of an inlet of the pressure adjusting device in terms of the flow direction.

Abstract: A method for cooling a fuel injection system and fuel injection systems are proposed that improve the hot-starting performance of the internal combustion engine.

Abstract: A pressure control valve serves to regulate the fuel pressure in a fuel system. The pressure control valve includes a valve housing, at least one inlet, at least one outlet, and at least one prestressed, electrically actuatable, and at least regionally ball-shaped valve member. The valve member cooperates with a valve seat structurally connected to the housing. To make it possible to achieve stable closed- and/or open-loop control properties of the pressure control valve, it is proposed that the valve seat widen conically toward the valve member, and the ball diameter of the valve member is selected such that with the valve closed, the valve member touches the valve seat in the vicinity of its farther end.

Abstract: The fuel supply apparatus for supplying fuel to an internal combustion engine has a fuel tank (2), a first fuel pump (6) that supplies fuel from the fuel tank to a fuel line (10), a second fuel pump (12) that supplies fuel from the fuel line (10) via a pressurized line to at least one fuel valve (16) and a fuel return line (22) that connects the fuel line (10) to the fuel tank for return of excess fuel. A shut off valve (30), which is closed at high temperatures, and a pressure regulator valve (26) are arranged hydraulically in series in the fuel return line (22). A fuel scavenger line (60) is provided, by which fuel at high temperatures is returned to the fuel tank (2). The fuel scavenger line (60) conducts the fuel back to the fuel tank (2), at least partially through the second fuel pump (12) and through a hydraulic resistance. Gas bubble formation is prevented by a high fuel supply pressure and by transfer of heat from the second fuel pump (12).

Abstract: A fuel supply system (1) for an internal combustion engine, especially of a motor vehicle, is described which is provided with an accumulator (2) and a pump (6, 10). Fuel can be supplied to the accumulator (2) with the pump (6, 10). A control apparatus (16) is provided for controlling (open loop and/or closed loop) the pressure in the accumulator (2) by a pressure control valve (4). With the control apparatus (16), the pressure control valve (4) can be closed when the engine is intended to be started but no rotational movement is yet present.

Abstract: In fuel delivery systems with two fuel pumps connected in series, two fuel distribution strips are provided in V-engines. Before now in this connection, there was the problem that in order to regulate the pressure in the two fuel distribution strips, a considerably high cost was required and/or the regulation of the pressure could not take place with the desired quality. In the fuel delivery system proposed here, a favorable pressure regulation in the two fuel distribution strips (21, 22) can be achieved by means of the one pressure control valve (30), with a minimum of rigid lines to be laid. The fuel delivery system is provided for an internal combustion engine of a vehicle.

Abstract: A high-pressure fuel pump which is suitable above all for use in internal combustion engines with direct gasoline injection, in which the pressure surge upon opening of a check valve between the high-pressure line and the pumping chamber of the fuel feed pump is limited by structural provisions.

Abstract: An internal combustion engine, in particular for a motor vehicle, which is provided with a fuel pump which can deliver fuel into a pressure reservoir. A control device is provided, which is connected to the fuel pump. The delivery quantity of the fuel pump can be changed and the fuel quantity supplied to the pressure reservoir can be adjusted to a required fuel quantity by influencing the delivery quantity of the fuel pump. The control device can control the delivery quantity of the fuel pump by a program map as a function of a number of input variables during the startup of the engine.

Abstract: A fuel supply system with two series-connected fuel pumps including a control valve, which is relatively small, and having a very precise regulation of the quantity of fuel pumped from the first pump into a pressure line by the second fuel pump is obtained at little effort or expense. The fuel supply system is intended for an internal combustion engine of a vehicle.

Abstract: A fuel supply system for an internal combustion engine, in particular of a motor vehicle, is equipped with a pressure accumulator and a high-pressure pump with which fuel can be delivered to the pressure accumulator. Also provided is a control device with which at least the pressure in the pressure accumulator can be controlled. When the internal combustion engine is in coastdown (overrun) mode, the pump output of the high-pressure pump can be reduced.

Abstract: A system for supplying an internal combustion engine with fuel present in a tank, in which a feed segment for the fuel extends from a feed pump through a fuel filter, is characterized in that the fuel filter includes a prefilter and a fine filter. It is especially suitable for supplying an internal combustion engine by direct injection.

Abstract: A fuel delivery systems with first and second fuel pumps connected in series in which, a satisfactorily precise regulation of the fuel quantity supplied by the second fuel pump is possible. In particular, a switching time of a control valve that controls the fuel quantity is very short. The control valve includes an electromagnet which holds the valve member in a starting position. The electromagnet is supplied with just enough current that the valve member remains in this position. A slight change of the current supply of electromagnet can then cause the switching of the control valve into the end position within an extremely short period of time. The fuel delivery system is provided for an internal combustion engine of a vehicle.

Abstract: A fuel-supply system for an internal combustion engine, particularly of a motor vehicle. The fuel-supply system is provided with a pump for delivering fuel into a storage chamber and for producing a pressure in the storage chamber. In addition, provision is made for a pressure sensor for measuring an actual value of the pressure in the storage chamber, as well as a pressure-control valve for influencing the pressure in the storage chamber. A control unit is provided with means by which the pressure in the storage chamber is controllable to a setpoint value. In addition, the control unit is provided with means by which the closed-loop control of the pressure in the storage chamber is able to be superseded by an open-loop control.

Abstract: A fuel injection system for internal combustion engines, having a high-pressure fuel pump which fills a high-pressure collection chamber with high fuel pressure. Injection lines lead away from the high pressure collection chamber to the individual injection valves. A prefeed pump that feeds fuel from a tank via a low-pressure line system into a work chamber of the high-pressure pump, and at least one control valve controls the high-pressure pumping quantity of the high-pressure pump. Control valves are inserted into the low-pressure line system that adjust the fuel filling flow into the work chamber of the high-pressure pump to the fill volume actually required for operation.

Abstract: The invention relates to a fuel pumping device for two-cycle engines with at least a one-piece housing, on which a pulse air connector (14), which is pneumatically connected with the crankcase of the two-cycle engine, a fuel aspiration connector and a fuel pressure connector are arranged, in which a diaphragm (41) on which pulse air acts, drives a pump piston (22) in connection with a diaphragm disk (42), in the course of which fuel being supplied from the tank (1) at the fuel aspiration connector during the pump aspiration stroke is aspirated via a flap valve (61) into the compression chamber (51) located upstream of the pump piston, and is pumped during the compression stroke via a further flap valve (71) into the fuel pressure connector and into a reservoir (73) and/or an injection valve (5). The pulse air connector (14) terminates in a housing chamber (13) located between the diaphragm (41) and the pump piston (22), and at least one spring element (15, 35, 94) acts on each side of the diaphragm (41).

Abstract: An injection valve is described, in particular for direct injection of fuel into a combustion chamber of an internal combustion engine, with a valve body having a valve opening surrounded by a valve seat to form a spray opening, and with a valve needle which is pressed into its closed position, has a closing head and extends through the valve opening so that the closing head which works together with the valve seat is in contact with the valve seat on the spray side when the valve is closed.

Abstract: A fuel injection valve, particularly an injection valve for fuel injection equipment of internal combustion engines, having a pump piston that can be activated using a piezoelectric or magnetostrictive actuator for exerting a translatory pump motion. A spray-discharge nozzle with at least one spray-discharge opening is hydraulically connected via a fuel pressure line to the pump piston. The spray-discharge nozzle opens when the fuel pressure produced by the pump piston in the fuel pressure line exceeds a predetermined threshold. In the fuel pressure line, at least one non-return valve is arranged so that it opens in the direction towards the spray-discharge nozzle and closes in the opposite direction.

Abstract: A fuel supply system with two series-connected pumps and fuel injection valves that inject fuel directly into a combustion chamber of an engine. The system includes a relief device. In a simple embodiment, the relief device can assure that the pressure in the pressure line can drop when the engine has been shutoff. The relief line may, however, also be embodied such that during the entire time of engine operation, the pressure in the pressure line can be lowered at any time as needed. The apparatus and the method are intended for an internal combustion engine of a vehicle.