Abstract: A fuel system includes a plurality of fuel injectors connected to a common drain conduit, and a plurality of isolation valve assemblies each positioned fluidly between the common drain conduit and one of the plurality of fuel injectors. Each isolation valve assembly includes a valve member movable between a closed position to block an injection control valve assembly in the fuel injector from the common drain conduit, and an open position, and a biaser biasing the isolation valve member toward the closed position such that fuel injectors are isolated from fluid pressure pulses produced by nozzle check actuation to limit cross-talk among the fuel injectors.

Abstract: A system for testing an evaporative emissions (EVAP) canister of a vehicle according to the present disclosure includes an evaporator configured to contain liquid fuel, a fuel vapor supply line configured to deliver a mixture of fuel vapor and carrier gas from the evaporator to the EVAP canister, and a fuel vapor supply valve disposed in the fuel vapor supply line. The test system further includes a gas density meter configured to measure a density of the fuel vapor mixture flowing through the fuel vapor supply line, and a valve control module configured to control a position of the fuel vapor supply valve to adjust a flow of fuel vapor from the evaporator to the EVAP canister based on the fuel vapor mixture density.

Abstract: An injection molding system, water jet cutting machine or other industrial system has a synthetically controlled variable displacement fluid working machine which outputs hydraulic fluid to one or more fluid consumers, such as rams or hydraulic motors, through hydraulically stiff fluid retaining volumes and receives hydraulic fluid back from one or more fluid consumers through the same or other said hydraulically stiff fluid retaining volumes. Individual piston cylinder assemblies can be allocated to different outputs. There may be no valve between the machine and the consumers. A working chamber of the machine can be caused to undergo a motoring cycle to enable the machine to output more power than is received from a motor driving the machine. An accumulator can be used to provide a source of hydraulic compliance. The machine can be controlled using pressure control, flow control, feed forward control or variable power/variable power limit control.

Abstract: A fuel supply apparatus for an internal combustion engine includes a fuel pump, a fuel pipe, a reduction valve, and an electronic control unit. The electronic control unit is configured to drive the fuel pump to rotate such that a required flow rate of the fuel is realized, while adjusting the fuel pressure in the fuel pipe to a target value, by driving the fuel pump to rotate. The electronic control unit is configured to operate the reduction valve to be opened when the operation state of the fuel pump is a first operation state. The first operation state is the operation state of the fuel pump where the frequency of the fuel pump has a value within a resonance area.

Abstract: An engine system and method for operating an engine including a central throttle and a port throttle is disclosed. In one example, the central throttle and port throttle are adjusted to improve air flow distribution to engine cylinders. The system and method may be particularly beneficial for turbocharged engines.

Abstract: A passive hydraulically actuated non-electric shutdown pressure relief valve relieves pressure in the high pressure volume of a low static leak common rail fuel system after shutdown. When the common rail fuel system is in operation, a transfer pump provides medium pressure to hold the shutdown pressure relief valve closed. At shutdown, the residual medium pressure downstream from the transfer pump decays back to tank, and the residual high pressure trapped in the common rail and fuel injectors pushes open the shutdown pressure relief valve to release the high pressure after back to tank.

Abstract: The injection system of a fuel injection pump is provided. In the injection system of a fuel injection pump, a plunger performs a reciprocating slide motion in the axial direction inside of the plunger chamber of a barrel for compressing fuel. The plunger has a release groove and a control edge. A spill port is formed in the wall surface of the barrel. A damping groove is formed in the upper-part outer circumference of the control edge and provides a fine fuel flow path. The damping groove meets the spill port in advance to form the fine flow of fuel from the plunger chamber to the spill port before the control edge of the plunger meets the spill port to release pressure.

Abstract: A system and method for operating a fuel system that supplies fuel to a plurality of injectors in an internal combustion engine via a first pump and a second pump with a bypass circuit returning fuel from between the first and second pumps to a fuel tank, the pumps connected in series, is provided. The bypass circuit increases its restriction to increase injection pressure during selected conditions.

Abstract: A controller for a pressure reducing valve is applied to a fuel injection system which is provided with a pressure reducing valve in a common-rail and a fuel pressure sensor detecting a fuel pressure in a fuel supply passage from the accumulator to an injection port of the fuel injector. The controller includes a fuel-pressure-variation detector for detecting a fuel pressure variation timing at which a detection value of the fuel pressure sensor is varied due to an opening operation or a closing operation of the pressure reducing valve. The controller further includes a response-delay-time computing portion for computing a response delay time of the pressure reducing valve based on a command timing and a fuel pressure variation timing.

Abstract: A fuel system for a dual fuel power source includes a first fuel circuit fluidly connected to the power source, a second fuel circuit separate from the first fuel circuit and fluidly connected to the power source, and a pressure regulator fluidly connected to the first fuel circuit. The pressure regulator is configured to vent a first fuel from the first fuel circuit to an aftertreatment system fluidly connected to the power source in response to a pressure difference between the first and second fuel circuits being less than or equal to a pressure difference threshold.

Abstract: A compression ignition dual fuel engine supplies natural gas fuel and liquid diesel fuel to each engine cylinder from a common fuel injector. Each fuel injector is fluidly connected to both a liquid fuel common rail and a gaseous fuel common rail. The engine includes a surplus gas system for capturing surplus gas, such as evaporated gas from the gaseous fuel supply and pressure control system, or left over pressurized natural gas produced by engine shut down. Rather than being vented to atmosphere, the surplus gas can be burned in the engine when operating conditions present burn opportunities.

Abstract: An engine system is disclosed that combusts both gaseous and diesel fuels. The system includes a diesel reservoir in communication with an internal combustion engine via a diesel rail. The system also includes a liquefied gaseous fuel reservoir in communication with the internal combustion engine via a gaseous fuel rail. The gaseous fuel and diesel rails both are in communication with a pressure control device. The pressure control device measures the pressure differential between the gaseous fuel and diesel rails. If the pressure differential exceeds a desired range, the pressure control device vents gaseous fuel from the gaseous fuel rail to a spark ignited engine, where the vent gas is used as fuel. The spark ignited engine then converts the vented gaseous fuel to useful work.

Abstract: The present invention concerns a pressure control valve system for a fuel line with a pressure line with a pressure control valve for maintaining a fuel pressure in the fuel line and a filling line for filling the fuel line with fuel, wherein an inlet of the pressure line is connected to an outlet of the filling line using fluid technology.

Abstract: The present invention provides an engine start system in a vehicle. The engine start system includes an engine and a charge system. The vehicle also includes an engine speed sensor for measuring a speed of the engine. The charge system is coupled to the engine and includes a charge pump. The vehicle further includes a control unit and a temperature sensor for sensing a temperature of fluid in the charge system. The temperature sensor is electrically coupled to the control unit. A bypass system is fluidly coupled to the charge system and includes a valve and a solenoid. The solenoid is electrically coupled to the control unit such that the control unit energizes the solenoid to control the valve in response to the speed measured by the speed sensor and the temperature sensed by the temperature sensor.

Abstract: A controlling apparatus of a variable capacity type fuel pump, for avoiding noises caused due to drive of the fuel pump and noises caused due to drive of injectors from overlapping or duplicating with each other in the timing thereof, wherein signals for driving the pump reduced, or the timing thereof is shifted forward/backward, within a specific timing where the o overlapping can be prospected, or a specific timing where they are determined to overlap or duplicate with each other.

Abstract: The invention relates to a fuel supply system (1) for injecting liquefied vapour under high pressure, such as liquid petroleum gas (LPG), into a combustion chamber (3-6) of an internal combustion engine (2). The fuel supply system (1) comprises a fuel supply for liquefied vapour connected to a high-pressure pump (11) via a duct. The high-pressure pump (11) has a high-pressure chamber (105) which is embodied thereby to increase the pressure of the liquefied vapour. A high-pressure discharge of the high-pressure pump (11) is connected to a high-pressure rail (7) which comprises one or several injectors for injecting liquefied vapour into a combustion chamber. According to the invention, the fuel supply system is provided with a discharge F unit (20) for purging fuel, in particular fuel vapour, between the high-pressure chamber and the combustion chamber.

Abstract: A pressure regulator is connected to a fuel pipe to which fuel is supplied by a feed pump. There is formed a fuel channel in the pressure regulator for returning fuel from within the fuel pipe to the fuel tank. In the pressure regulator, there is also formed a stopper which can come into contact with a valve body when the valve body is displaced as a result of an increase in fuel pressure within the fuel pipe. The stopper reduces the fuel flow area of the fuel channel when the valve body is displaced as a result of the increase in the fuel pressure within the fuel pipe. Thus, the fuel flow area of the fuel channel is reduced as mentioned above when the fuel pressure within the fuel pipe is high. This makes the fuel within the fuel pipe less likely to be released through the aforementioned fuel channel.

Abstract: The present invention relates to a fuel injector for injecting fuel into a combustion chamber of an internal combustion engine, having a valve piston that is displaceably guided in an injector body in terms of lifting motions, whereby the lifting motion of the valve piston can be controlled by a control valve. The control valve has a valve needle with a guide bore, so that the needle is displaceably guided in the direction of a lifting axis in terms of lifting motions. A guide section integrally formed on an end of a valve piece extends into the guide bore for the displaceable guidance of the valve needle in terms of lifting motions. Along the lifting axis a vertical bore extends through the valve piece into the guide section, such that fuel is able to flow through the bore from a control chamber into an annular chamber introduced between the guide bore and the guide section for controlling the lifting motion of the valve piston.

Abstract: A nozzle injection apparatus for use in internal combustion engines includes a fuel pump for intermittently pressurizing fuel, an injection conduit in fluid communication with the fuel pump, the injection conduit permitting the pressurized fuel to be communicated to a fuel injection nozzle a control valve in fluid communication with the nozzle, wherein the control valve dynamically and selectively controls a pressure of said pressurized fuel within the injection conduit.

Abstract: Fuel supply equipment for a vehicle includes a fuel filter cover for covering a fuel filter that is disposed outside of a fuel tank. A fuel pressure regulator for keeping fuel supplied to a fuel injection system under predetermined pressure is arranged so that the fuel pressure regulator is located inside the fuel filter cover and is overlapped with the fuel filter cover when a vehicle is viewed from the side. The fuel pressure regulator is connected to an outflow side of the fuel filter via a fuel hose for keeping fuel supplied to a fuel injection system under predetermined pressure. A holder for supporting the fuel pressure regulator is attached to the fuel filter cover before it is attached to a body frame. The resulting configuration enhances the ability to install and maintain a fuel filter provided outside the fuel tank.

Abstract: The invention relates to a high-pressure fuel pump for an internal combustion engine with direct injection, comprising a pump housing, a low-pressure region on the intake side, and a high-pressure region on the output side. The high-pressure fuel pump comprises a purely mechanical pressure regulating device for regulating a constant pressure in the high-pressure region.

Abstract: A fuel pressure regulation system for a compression ignition diesel engine. The system comprises a fuel supply line connected to an inlet of a transfer pump and a transfer pressure fuel line connected between the transfer pump outlet and the high pressure fuel pump inlet. A fuel filter is positioned in the transfer pressure fuel line and a fuel spill line fluidly connects a fuel pressure regulator to the transfer pressure fuel line at a point between the transfer pump outlet and the fuel filter. A fuel return line is connected between the fuel pressure regulator and the fuel supply line and a control fuel line is connected between the fuel pressure regulator and the transfer pressure fuel line. The fuel pressure regulator comprises a bore within which is located a valve member moveable from a non-regulating position of the fuel pressure regulator to a regulating position of the fuel pressure regulator.

Abstract: The injection system (1) includes a storage volume (6) of pressurized fuel supplied by a high-pressure pump (7) along a delivery pipe (8); and a control unit (16) for defining the required fuel pressure of the storage volume (6) as a function of the operating conditions of the engine (2). The regulating device includes a bypass solenoid valve (14); and a pair of non-return valves (32, 33) connected antiparallel and located between the bypass valve (14) and the storage volume (6). One of the non-return valves (32, 33) permits fuel drainage from the storage volume (6) to the bypass valve (14) when the control unit (16) defines a predetermined reduction (?p) in the fuel pressure of the storage volume (6).

Abstract: A fuel supply system for an accumulator fuel injection system designed to inject fuel, as stored in an accumulator, into an internal combustion engine through a fuel injector The fuel supply system includes a feed pump working to pump the fuel out of a fuel tank and a fuel filter disposed between the feed pump and a high-pressure pump working to deliver the fuel to the accumulator. The fuel supply system also includes a return path and a control valve. When the pressure of the fuel between the fuel filter and the flow rate control valve exceeds a first set pressure, the control valve opens the return path to return the fuel from downstream to upstream of the feed pump to keep the pressure of fuel supplied to the flow rate control valve below the first set pressure, thereby controlling the flow rate of the fuel passing through the fuel filter.

Abstract: A pump unit for a fuel injection system of an internal combustion engine is arranged along a fuel feed circuit and has a pre-feed pump and a high-pressure pump which has a pump body and a flange joined to the pump body. The feed circuit is provided with a feed branch and a delivery branch of the pre-feed pump which are formed, at least partly, in the flange of the high-pressure pump.

Abstract: Disclosed is a pressure regulator for a fuel supply unit of a motor vehicle comprising a valve for joining a connection to an outlet above a designated pressure in the connection, a valve body and a valve seat, and a spring element for prestressing the valve body against the valve seat, characterized in that the valve body is designed as a sheet-metal part.

Abstract: The invention relates to a machine tool having working field illumination disposed in a housing, having an illumination mechanism and a transparent element which allows the light from the illumination mechanism to be led out toward the working field. A light beam can be deflected between the illumination mechanism and the transparent element. According to the invention, the transparent element forms a region of the housing.

Abstract: A fuel system control method may include determining when an engine transitions from an engine on condition to an engine off condition. The method further includes determining a first fuel pressure in a fuel system of the engine a predetermined time after the determined engine off condition. A fuel injector of the fuel system may be actuated during the engine off condition when the first determined fuel pressure is above a first predetermined pressure limit to bleed fuel from the fuel system and reduce pressure within the fuel system.

Abstract: A fuel supply apparatus for an engine may include a plurality of common rails that stores fuel under relatively different pressures, and at least an injector that is connected to the common rails to be independently supplied with the fuel and selectively inject the fuel in any one of the connected common rails.

Abstract: A fuel supply system includes a fuel pump for supplying fuel in a fuel tank to an engine, a pressure regulator and a three-way valve disposed in a valve chamber. The pressure regulator includes a pressure regulating chamber and a control pressure chamber and adjusts a fuel pressure in the pressure regulating chamber depending on a fuel pressure in the control pressure chamber. A control pressure passage for flowing the fuel to the control pressure chamber and the valve chamber is formed in a unit case.

Abstract: The fuel injection system has at least two electrically actuated control valves for controlling the fuel injection; the control valves are each connected via electric lines to an electric control unit. In the fuel injection system, terminal elements for connection of the electric lines are provided. For a first of the control valves, a structural element is provided, on which the terminal elements for all the control valves are disposed, and which can be secured to a housing part of the fuel injection system. At least one electric connecting line from the terminal elements to the second control valve disposed inside a housing part of the fuel injection system is integrated with the structural element.

Abstract: A fuel pump module comprising a fuel pump, a pressure regulator, a supply line check valve, a relief valve, and a flange adapted to engage a fuel supply line that fluidly links the fuel pump module with an injector rail. The pressure regulator is adapted to maintain a predetermined fuel pressure between the fuel pump and the supply line check valve. The supply line check valve is adapted to facilitate a minimum fuel pressure in the fuel supply line. The relief valve is adapted to limit the maximum fuel pressure in the fuel supply line. The supply line check valve, the relief valve, and the flange are integrated to form a single fluidly interconnected structure disposed within a fluid path between the pressure regulator and the fuel supply line. An integrated casing may house the fuel pump and the pressure regulator.

Abstract: A relief valve is provided for use with a fuel system. The relief valve may have a housing forming an inlet, an outlet, and a central bore fluidly connecting the inlet to the outlet. The relief valve may also have a valve element disposed within the central bore of the housing and being configured to move between a flow-passing position and a flow-blocking position. The valve element may have a passageway continuously communicating the inlet of the housing with the outlet of the housing. The relief valve may also have a resilient member situated to bias the valve element toward the flow-blocking position.

Abstract: A fuel supply method and circuit including at least one flow-rate regulating valve is provided at a return pipe for returning excess return fuel from a combustion chamber side. During the combustion operation, the fuel from the supply pipe is supplied to a fuel injection nozzle with the return pipe closed or restricted to a predetermined opening degree and the back pressure of the return pipe raised by at least one flow-rate regulating valve. The fuel is supplied to the fuel injection nozzle as being pressurized by the return back pressure, so that the fuel injection nozzle supplies to the combustion chamber the fuel that has been heated to a high-temperature. The return fuel is circulated from the return pipe directly through the supply pipe, and mixed in a sub-tank with low-temperature fuel from a fuel tank. The mixed fuel is supplied to the fuel injection nozzle.

Abstract: A control method of a direct injection system of the common-rail type provided with a shut-off valve for controlling the flow rate of a high-pressure fuel pump; the control method contemplates the steps of: feeding the pressurized fuel to a common rail by means of a high-pressure pump which receives the fuel through a shut-off valve; cyclically controlling the opening and closing of the shut-off valve for choking the flow rate of fuel taken in by the high-pressure pump; adjusting the flow rate of fuel taken in by the high-pressure pump by varying the ratio between the duration of the opening time and the duration of the closing time of the shut-off valve; determining a lower limit value of the opening time of the shut-off valve; and adjusting the driving frequency of the shut-off valve so that the real opening time of the shut-off valve is always over the lower limit value.

Abstract: A method for maintaining and/or adjusting a system pressure in a fuel injection system of an internal combustion engine, in which the internal combustion engine is a part of an hybrid power train, which includes in addition at least one further drive. A system pressure in a reservoir element of the fuel injection system is monitored using a pressure sensor. In operating modes in which the internal combustion engine is shut down and/or is separated from the hybrid power train, the maintaining or the adjusting of the system pressure takes place via a pressure-regulating valve. The activation of the pressure-regulating valve takes place directly or indirectly via a control unit or a vehicle control unit or a clutch control unit.

Abstract: A check valve includes a body defining a passageway through which fuel flows in a first fuel-flow direction during pump operation. The check valve also includes a seat, a seal member, and a biasing member biasing the seal member toward the seat. The seal member is movable between a first seated position in which the seal member is engaged with the seat and the pressure in the fuel rail is substantially equal to the operating pressure, and a second seated position in which the seal member is engaged with the seat and a residual pressure in the fuel rail is substantially less than the operating pressure. The seal member and the seat define a leak path between the fuel pump and the fuel rail permitting fuel to flow in a second fuel-flow direction opposite the first fuel-flow direction when the seal member is in the second seated position.

Abstract: An internal combustion engine has a fuel delivering device with a high-pressure pump which conveys fuel into a fuel reservoir, and a volume flow control valve that is assigned to the high-pressure pump. A control difference (FUP_DIF) is determined from a difference between a predefined fuel pressure (FUP_SP) and a detected fuel pressure (FUP_AV). The control difference (FUP_DIF) is fed to a controller that encompasses at least one integral portion (I_CTRL). A corrective value (COR) for an error value of a fuel flow rate is determined in accordance with the integral portion (I_CTRL) of the controller if a sum of the integral portion (I_CTRL) exceeds a given threshold value during a predefined mode of operation of the internal combustion engine. In addition, an actuating signal (PWM) for the volume flow control valve is generated according to a controller value (FUEL_MASS_FB_CTRL) and the corrective value (COR).

Abstract: In a method for determining the closure time for a valve, operated by a piezoelectric actuator, in order to record the closing time, the voltage at the piezoelectric actuator is recorded and the time is recorded at which the voltage has a maximum difference value from a comparison curve. The difference curve is generated between a start and an end point for a measured curve, having the voltage values applied to the piezoelectric actuator. A precise determination of the closing time can thus be carried out.

Abstract: A method in an internal combustion engine for controlling a fuel injector of the unit injector type which includes a plunger that is driven by a rotating camshaft and during a working stroke generates a hydraulic pressure increase in the fuel. Pressure build-up is regulated by a spill valve the injection sequence is regulated by a needle control valve. The spill valve and the needle control valve are regulated in such a way that additional plunger retardation force is produced in a part of a working stroke in addition to the normal retardation force that is produced by the plunger return spring and the flow resistance in the injector.

Abstract: The injection system comprises a high-pressure pump with variable flowrate, having at least one pumping element provided with an intake valve in communication with an intake pipe and a delivery valve in communication with a delivery pipe. A pressure regulator is set on the intake pipe downstream of a metering solenoid valve designed to meter the flowrate of the pump according to the operating conditions of the engine. The pressure regulator is designed to discharge the excess fuel into a compartment of a crankcase for lubricating the usual actuation mechanism of the pumping element. Set between an inlet of the solenoid valve and an inlet of the pressure regulator is a control volume designed to contain an amount of fuel such as to guarantee an adequate flow of fuel in an area corresponding to the inlet of the solenoid valve.

Abstract: A method for detecting the opening of a passive pressure control valve, which conducts fuel from a common rail system back to a fuel tank, in which the rail pressure (pCR) is automatically controlled by calculating a correcting variable for acting on the controlled system from a rail pressure control deviation via a pressure controller, and in which, starting from a steady-state rail pressure in normal operation, a load reduction is detected when the rail pressure exceeds a first limit. Opening of the pressure control valve is detected after the first limit is exceeded if a steady-state operating state is subsequently detected again, and if a characteristic of the closed-loop control system deviates significantly from a reference value.

Abstract: A pressure relief valve useful in vehicle fuel delivery systems includes a spring biased, concave conical flow directing surface and a spherical valve seat.

Abstract: A pressure regulator includes a housing, a divider including a first valve member, and a second valve member. The housing includes an inlet and an outlet, and defines an interior volume. The divider separates the interior volume into first and second chambers, and included the first valve member, a diaphragm, and a retainer. The diaphragm extends between the housing and the first valve member. Fluid communication between the first and second chambers through the diaphragm being prevented. The retainer secures the diaphragm relative to the first valve member, and the retainer is press-fitted with respect to the first valve member. The second valve member is arranged between first and second configurations relative to the first valve member. The first configuration substantially prevents fluid communication between the inlet and the outlet, and the second configuration permits fluid communication between the inlet and the outlet.

Abstract: A pressure regulator includes a housing, a divider, and a valve. The housing includes an inlet and an outlet. The divider separates the housing into a first chamber and a second chamber. And the valve includes a spherical valve ball and a seat. The spherical valve ball is fixed with respect to a first one of the housing and the divider, and the seat is fixed with respect to a second one of the housing and the divider. A first configuration of the spherical valve ball with respect to the seat substantially prevents fluid communication between the inlet and the outlet, and a second configuration of the spherical valve ball with respect to the seat permits fluid communication between the inlet and the outlet.

Abstract: A pump assembly includes a high-pressure pump that flows pressurized working fluid in a fuel injection system of a diesel engine. The assembly includes a pilot-operated inlet throttle valve that receives a flow of low-pressure fluid from a feed pump and controls the volume of fluid flowed to the high-pressure pump in response to an electronic control module for the diesel engine. The operation of the inlet throttle valve is independent of fluctuations in output pressure from the feed pump.

Abstract: A flow-through pressure regulator includes a retainer that secures a diaphragm relative to a seat, and includes an intermediate portion, an end portion and a base portion. The intermediate portion extends along a longitudinal axis and is fixed with respect to the seat. The end portion extends from the intermediate portion and includes a concave surface facing the seat. The regulator includes multiple flow diffusers such that the end portion includes at least one aperture having a flow axis that is oblique to the longitudinal axis so as to reduce noise due to fluid flow and/or the seat forms a passage having an increasing cross-sectional area from an inlet to an outlet.

Abstract: A fuel return valve comprises a housing and a closing unit, a first passage, which is line-connected to a fuel pump, a second passage, which is line-connected to an internal combustion engine, and a third passage, which is line-connected to the fuel tank, as well as a pressure chamber, being formed in the housing, which pressure chamber is in communication with the first passage, and, via the closing unit, with the third passage. To make a valve of this type maintenance-free and simple and inexpensive to produce, the closing unit is a piston which is guided in the housing attachment and is pressed by a spring arranged and supported in the housing attachment onto a sealing surface which is formed on the housing and surrounds the pressure chamber, and an annular chamber which is in communication with the third passage and with the space containing the spring is formed outside the sealing surface.

Abstract: A pressure regulation assembly of a fuel supply includes a receptacle, an inlet connectable to the fuel supply and in fluid communication with the receptacle, an outlet in fluid communication with the receptacle, and a pressure regulator mounted in the receptacle to selectively open fluid communication between the inlet and the outlet. The receptacle includes a first surface surrounding an axis, and a second surface surrounding the axis and the first surface to provide a void between the first surface and the second surface. The pressure regulator extends into the void between the first surface of the receptacle and the second surface of the receptacle and includes a third surface surrounding the axis and a fourth surface surrounding the axis and the third surface. A first seal engages the first surface of the receptacle and the third surface of the pressure regulator. A second seal engages the second surface of the receptacle and the fourth surface of the pressure regulator.

Abstract: In a common rail type fuel injection system, fuel in a fuel tank is sucked by a feed pump and fed to a pressurizing pump. Fuel pressurized in the pressurizing pump is supplied to a common rail. The pressurized fuel accumulated in the common rail is injected into a cylinder of an internal combustion engine from an injector. All of these operations are electronically controlled by an electronic control unit. To gradually suck air in the fuel tank together with fuel and to avoid air accumulation in a fuel filter, a relief valve is connected to the common rail. The relief valve is opened when the engine is idling thereby to increase an amount of fuel sucked by the feed pump and to gradually suck the air together with the fuel. The relief valve is opened only in interval periods in which fuel is not injected from the injector.