Abstract: In a fuel-injection system with a pressure regulator disposed in the middle of a fuel supply line and located upstream of a fuel injector for regulating the pressure of fuel flowing through the fuel supply line and for returning surplus fuel via the pressure regulator into a fuel tank, a reflux pipe arrangement is located downstream of the fuel injector and connected at one end to the downstream end of the fuel supply line and connected at the other end to the fuel tank. A reflux control device is disposed in the middle of the reflux pipe arrangement for controlling a flow rate of the fuel flowing through the reflux pipe arrangement. The reflux control device is comprised of a reflux control valve or a fluid-flow restriction orifice member.

Abstract: A fuel injection system for internal combustion engines includes an injector supplied from a high-pressure fuel source and a pressure booster device, in which the pressure booster device has a movable pressure booster piston that disconnects a chamber that is connectable to the high-pressure fuel source from a high-pressure chamber communicating with the fuel injector, and by filling a return chamber of the pressure booster device with fuel and by evacuating the return chamber of fuel, the fuel pressure in the high-pressure chamber can be varied, and the fuel injector has a movable closing piston, for opening and closing injection openings, which protrudes into a closing pressure chamber, so that the closing piston can be subjected to fuel pressure to attain a force acting in the closing direction on the closing piston, and the closing pressure chamber and the chamber are formed by a common work chamber, and all the portions of the work chamber communicate permanently with one another for exchanging fuel.

Abstract: The present invention comprises a housing main body, a valve assembly disposed within the housing main body and provided with a valve main body having a large-diameter cylinder portion and a small-diameter cylinder portion, a valve seat having a fuel injection aperture secured within the valve main body and a needle valve for closing and opening the fuel injection aperture, a seal ring held between a cylinder head and a shoulder portion when the valve assembly is inserted into an insertion port in the cylinder for preventing combustion gas in the cylinder from leaking into the housing main body and a welded joint for securing the valve main body to the housing main body disposed between the side of the large-diameter cylinder portion and an engaging portion on the housing main body.

Abstract: The invention relates to a fuel supply system for an internal combustion engine, having a unit such as a pressure regulator, mounted in electrically insulated fashion and including an electrically conductive housing, and the housing is connected via an electrical connection to a defined electrical potential. As a result, static charging of the unit, which could become dangerous, is precluded. The fuel supply system is intended in particular for pumping fuel to an internal combustion engine of a motor vehicle.

Abstract: Each of two fuel tanks is disposed at a respective side of a chassis of a motor vehicle and has a respective sender for indicating the level of liquid fuel in the respective tank. A pump draws fuel from the tanks through a respective fuel draw conduit. Excess fuel is returned to each tank through a respective fuel return conduit. When the senders indicate an imbalance of fuel between the two tanks, a valve mechanism controlled by the senders disallows return fuel flow to the tank whose sender indicates that the level of fuel is greater than that indicated by the sender of the other tank by some defined amount while the pump continues to draw fuel from both tanks through the fuel draw conduits.

Abstract: A fuel delivery unit for an internal combustion engine including a housing, which includes a timing unit for shifting the point of injection of fuel into the combustion chambers of the internal combustion engine. An injection timing piston is accommodated in the timing unit, which is displaceably mounted in the timing unit and which encloses a trailing piston displaceably relative thereto. The timing unit contains a pressure chamber which may be pressurized/depressurized via an actuator, a cold start accelerator piston being movable via the pressure chamber, acting upon both the trailing piston via a spring element and, together with a spring-sleeve combination, influencing the injection timing piston.

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 for a vehicle, the fuel supply system being comprised of a fuel tank, a fuel pump installed in the fuel tank, a fuel level detection unit which is comprised of a float and a sensor member which detects a vertical displacement of the float, and a pressing member which presses with elasticity the sensor member against the inside bottom of the fuel tank.

Abstract: An accumulator type fuel injection system adapted to prevent engine trouble by making a judgement that fuel injection rate switching change-over valves provided correspondingly to fuel injection nozzles in cylinders, a valve for controlling the pressure in a low-pressure accumulator or means for detecting fuel pressures in accumulators gets out of order, and carrying out when any of these parts break down a control operation of a limp-home mode in which a region of an operation of an engine is limited. To provide such an accumulator type fuel injection system, a control means 8 is formed so that, when a judgement that first control valves 5, a second control valve 34 or pressure sensors 3a, 4a for detecting the fuel pressures in the respective accumulators get out of order is given, the control means 8 sets a discharge pressure of a fuel pump 1 not higher than a permissible pressure in a second accumulator 4, and injects a fuel from fuel injection nozzles 9.

Abstract: A pump assembly flows pressurized engine oil to hydraulic injectors in a diesel engine. The assembly includes a high-pressure pump with a bored piston passage. The outer end of the piston bore is closed by a plug assembly pressed in the bore.

Abstract: In a pressure accumulator vessel of a high pressure fuel supply device, a chamfered section is formed in a connection between an accumulation chamber and a corresponding fuel passage. An inner plated part, which includes a plating layer, is formed along a wall surface of the accumulation chamber, a wall surface of the fuel passage and a wall surface of the chamfered section. The pressure accumulator vessel further includes connecting portions and sealing portions. The connecting portion is formed to join with a fuel pipe. The sealing portion is formed adjacent to the connecting portion to fluid-tightly engage with the fuel pipe. Each unplated part is formed along a wall surface of the corresponding connecting portion and a wall surface of the corresponding sealing portion.

Abstract: An internal combustion engine and method of operating same is provided which includes a plurality of first cylinders and at least one second cylinder. The at least one second cylinder serves as an input cylinder in that a portion of the exhaust gas therefrom is fed by way of an exhaust gas recirculating system to carbureted fuel for the engine. The engine includes an injection system for injecting fuel into the first cylinders and into the at least one second cylinder. The injected fuel quantity of the at least one second cylinder is controlled independently of the injected fuel quantity of the first cylinders.

Abstract: An evaporative fuel emission control system includes a canister that adsorbs fuel vapor generated in a fuel tank, a canister outgoing gas producing unit that causes a canister outgoing gas to flow out of the canister, a vapor condensing unit that condenses the canister outgoing gas to provide a processed gas containing a higher concentration of fuel vapor than that of the canister outgoing gas, and a processed gas passage through which the processed gas is fed to the fuel tank. A controller of this system is operable to restrict flow of the processed gas into the fuel tank when the fuel vapor concentration in the processed gas is lower than or is expected to be lower than a predetermined level.

Abstract: A load timer mechanism of a fuel injection pump includes a governor shaft, which is secured to a housing, and a governor sleeve, which is axially slidably supported around the governor shaft. The governor shaft includes a fuel relief passage, which is communicated with a low pressure side of the pump and has an outer opening in an outer peripheral surface of the governor shaft, and a first annular groove, which is recessed in the outer peripheral surface of the governor shaft such that the first annular groove is axially displaced from the outer opening. The governor sleeve includes a port, which extends between an outer peripheral surface and an inner peripheral surface of the governor sleeve, and a second annular groove, which is recessed in the inner peripheral surface of the governor sleeve such that the second annular groove is axially displaced from the port.

Abstract: A mounting device for securing a fuel injector in a cylinder head of an internal combustion engine has at least one hold-down device which is mounted on a front face of the cylinder head and secures fuel injector in a receiving bore of the cylinder head. The at least one hold-down device is supported by a shoulder which is formed at the downstream end of the fuel injector and surrounds the fuel injector at least partially.

Abstract: A fuel injection pump includes a cam shaft (7) driving a plunger (4) and a feed pump (3) assembled therein for feeding fuel pressured by the plunger (4). A flange part (52) projecting radially is provided on the cam shaft (7), an internal gear (41) transmits a power to the feed pump (7), and a housing member (8c) rotatably supports the cam shaft (7) on the free end opposite to the end part of the driven side of the cam shaft (7). A housing member (8c) rotatably supporting the cam shaft (7) through a radial bearing (12) is held between the flange part (52) and the internal gear (41) so as to allow adjustment of the axial position of the cam shaft (7), so that adjustment of the axial position of the cam shaft is substituted for the existing member assembled into the pump. Thus, an axial gap due to a deterioration of durability of the bearing is eliminated to be adjusted so as to facilitate the assembly, reduce the number of parts, and reduce the size of the injection pump.

Abstract: A novel injection-pump plunger used in a unit injector for an EMD-type diesel engine has its upper (cut-off) control edge shaped to retard start of injection at full power from what it is with standard plungers, and to provide in a straight-line manner a relatively small increase in retardation from full load to idle. In a preferred form, the plunger has one or more steps in its upper (cut-off) control edge, the step or steps being formed between adjacent segments of the edge that are associated with different load points. A method of improving emissions/fuel-economy of EMD diesel engines comprises using prototype injection-pump plungers shaped within certain parameters, assessing their performance, selecting new patterns of timing based on the assessment, making new prototype plungers and assessing them, and repeating the steps of selecting, making and assessing if and as required until an assessment indicates compliance with applicable performance standards.

Abstract: A fuel injection pump includes a plurality of plungers and a cam shaft having a plurality of drive cams (31, 32) corresponding to the plungers. The cam shaft is rotated by a power from the outside so as to reciprocate the plurality of plungers by the corresponding drive cams, and fuel is pressurized and force-fed in the forward stroke of each plunger. All or a part of the drive cams (31, 32) are installed with the phase thereof shifted, and the cam lobes (31a, 32a) of the drive cams are formed asymmetrical so that the amount of displacement of the plungers relative to a unit cam rotating angle is reduced in the forward stroke more than in the backward stroke of the plunger. Thus, the pressure variation in a common rail is reduced, the pressure resistance of the entire system is lowered, and the drive torque is reduced so as to reduce the load and noise of a drive system.

Abstract: A method and apparatus for controlling a fuel injector assembly of an internal combustion engine during cold operation thereof is disclosed. If a combustion-absent condition is detected in one or more of the cylinders associated with the engine, an engine control module cuts out the affected cylinders thereby preventing additional fuel from being delivered to the cylinders for a predetermined period of time, such as 4-5 seconds. During the period of time in which the cylinders are cut out, the pistons in the remaining cylinders associated with the engine continue to operate thereby heating the engine block. After the predetermined period of time, fuel is again injected into the cylinders if a combustion-present condition is detected therein.

Abstract: Steel fuel rails are provided with the mechanical components of a plurality of fuel injector valve bodies. The electronics for operating those valves are molded into an injector pack. The valve bodies are inserted into the passages associated with the injector pack such that the electronics are part of a single molded plastic portion. A corrugated seal is sealed to an outer portion of the passage on the injector pack. Thus, the present invention eliminates the number of connections for supplying fuel that needed to be sealed in the prior art. Further, the number of required assembly steps is reduced over the prior art.