Abstract: A high-pressure pump includes a pressurizing chamber forming portion, a suction passage forming portion, a seat member, a valve member, a cylindrical member, a needle, a movable core, a biasing member, a fixed core, and a coil including a winding portion. The coil generates an attractive force between the fixed core and the movable core when the winding portion is energized. The coil includes an outer cylindrical surface and multiple inner cylindrical surfaces that have different diameters. The multiple inner cylindrical surfaces are arranged in order of increasing diameter in a direction toward a pressurizing chamber. The movable core has an end surface that faces the fixed core, and the end surface of the movable core is located between a center, in an axial direction, of a smallest diameter one of the plurality of inner cylindrical surfaces and a center, in an axial direction, of the outer cylindrical surface.

Abstract: A damper device arranged in a housing space formed between a device main body and a cover member includes a pair of damper bodies each having a plate and a diaphragm and having an enclosed space sealed with gas. A biasing device is provided between the pair of damper bodies arranged facing each other and configured to bias the damper bodies from one side of the device main body and the cover member to the other side of the device main body and the cover member, stay members each extending from an outer peripheral edge portion of each of the damper bodies and brought into contact with other side, and a frame member arranged on one side of the device main body and the cover member and having a stopper portion configured to restrict movement of the damper bodies in the direction of the other side.

Abstract: A high-pressure pump includes a pressurizing chamber forming portion, a suction passage forming portion, a seat member, a valve member, a cylindrical member, a needle, a movable core, a biasing member, a fixed core, and a coil including a winding portion. The coil generates an attractive force between the fixed core and the movable core when the winding portion is energized. The coil includes an outer cylindrical surface and multiple inner cylindrical surfaces that have different diameters. The multiple inner cylindrical surfaces are arranged in order of increasing diameter in a direction toward a pressurizing chamber. The movable core has an end surface that faces the fixed core, and the end surface of the movable core is located between a center, in an axial direction, of a smallest diameter one of the plurality of inner cylindrical surfaces and a center, in an axial direction, of the outer cylindrical surface.

Abstract: A high-pressure pump includes a pressurizing chamber forming portion, a suction passage forming portion, a seat member, a valve member, a cylindrical member, a needle, a movable core, a biasing member, a fixed core, and a coil including a winding portion. The coil generates an attractive force between the fixed core and the movable core when the winding portion is energized. The coil includes an outer cylindrical surface and multiple inner cylindrical surfaces that have different diameters. The multiple inner cylindrical surfaces are arranged in order of increasing diameter in a direction toward a pressurizing chamber. The movable core has an end surface that faces the fixed core, and the end surface of the movable core is located between a center, in an axial direction, of a smallest diameter one of the plurality of inner cylindrical surfaces and a center, in an axial direction, of the outer cylindrical surface.

Abstract: A damper device arranged in a housing space formed between a device main body and a cover member includes a pair of damper bodies each having a plate and a diaphragm and having an enclosed space sealed with gas. A biasing device is provided between the pair of damper bodies arranged facing each other and configured to bias the damper bodies from one side of the device main body and the cover member to the other side of the device main body and the cover member, stay members each extending from an outer peripheral edge portion of each of the damper bodies and brought into contact with other side, and a frame member arranged on one side of the device main body and the cover member and having a stopper portion configured to restrict movement of the damper bodies in the direction of the other side.

Abstract: A high-pressure pump includes a pressurizing chamber forming portion, a suction passage forming portion, a seat member, a valve member, a cylindrical member, a needle, a movable core, a biasing member, a fixed core, and a coil including a winding portion. The coil generates an attractive force between the fixed core and the movable core when the winding portion is energized. The coil includes an outer cylindrical surface and multiple inner cylindrical surfaces that have different diameters. The multiple inner cylindrical surfaces are arranged in order of increasing diameter in a direction toward a pressurizing chamber. The movable core has an end surface that faces the fixed core, and the end surface of the movable core is located between a center, in an axial direction, of a smallest diameter one of the plurality of inner cylindrical surfaces and a center, in an axial direction, of the outer cylindrical surface.

Abstract: In one embodiment, a small-diameter opening (42b) is formed in the central portion of a valve element (42) included in a check valve (40) of a high pressure fuel pump (1). A needle valve (44) is provided integrally with a valve element (35a) of an electromagnetic spill valve (30), and the opening (42b) of the valve element (42) can be opened and closed with a tip portion of the needle valve (44). When the high pressure fuel pump (1) switches from the drive state to the stopped state, the needle valve (44) retreats from the opening (42b) of the valve element (42) in conjunction with the movement of the valve element (35a) of the electromagnetic spill valve 30, thus forming a micro gap.

Abstract: A relief valve includes a valving element, a movable holder, a housing having a guide hole and a valve seat, and a resilient member. The valving element is lifted from its seated state, in which the valving element is engaged with the valve seat, toward a pressurizing chamber in a lift period. The lift period includes a lift first period and a lift second period. An amount of the lift of the valving element reaches a set distance in the lift first period. The lift second period is after the amount of the lift of the valving element has reached the set distance. The movable holder slides inside the guide hole both in the lift first period and in the lift second period. A minimum clearance area between the movable holder and the guide hole is larger in the lift second period than in the lift first period.

Abstract: A fuel pump includes a housing having therein a suction passage and a pressurization chamber into which fuel from the suction passage flows, a plunger held in the housing to be reciprocable so as to pressurize the fuel flowing into the pressurization chamber, and a diaphragm device located in a suction chamber that is provided in the suction passage. The diaphragm device includes a pair of first and second diaphragms that are arranged to define an inner space therebetween and air-tightly sealed at its entire peripheries. A mass addition member may be attached to an inside surface of at least one of the first and second diaphragms, so that the first and second diaphragms with the mass addition member have different characteristic frequencies. Accordingly, pressure pulsation of the fuel in the suction chamber can be effectively reduced by the pulsation damper.

Abstract: A volume chamber is formed by a valve member, an inner peripheral wall of a tubular portion and a bottom portion of a stopper when the valve member is engaged with tubular portion. A communication passage communicates between the volume chamber and one of an intermediate passage of a valve body and a tertiary passage of the stopper. The communication passage is formed at a location, which is spaced from a contact surface between the tubular portion and the valve member by a first predetermined distance and is also spaced from a contact surface between the bottom portion and the first urging member by a second predetermined distance.

Abstract: A fuel pump includes a pump housing having a compression chamber. A plunger is axially movable in the pump housing for pressurizing fuel in the compression chamber. A discharge valve is configured to open to supply fuel from the compression chamber to an internal combustion engine when pressure in the compression chamber is more than predetermined pressure. A fuel passage is configured to communicate a downstream of the discharge valve with an upstream of the discharge valve. An in-passage member is accommodated in the fuel passage. The in-passage member includes multiple members, which are combined to define a throttle portion for restricting fuel, which returns from the downstream of the discharge valve to the upstream of the discharge valve.

Abstract: In one embodiment, a small-diameter opening (42b) is formed in the central portion of a valve element (42) included in a check valve (40) of a high pressure fuel pump (1). A needle valve (44) is provided integrally with a valve element (35a) of an electromagnetic spill valve (30), and the opening (42b) of the valve element (42) can be opened and closed with a tip portion of the needle valve (44). When the high pressure fuel pump (1) switches from the drive state to the stopped state, the needle valve (44) retreats from the opening (42b) of the valve element (42) in conjunction with the movement of the valve element (35a) of the electromagnetic spill valve 30, thus forming a micro gap.

Abstract: A fuel gallery has an inlet opening through which a fuel is introduced therein and a suction opening through which the fuel flows between the fuel gallery and a compression chamber. A pulsation damper is supported in the fuel gallery by a first and a second supporting member. The second supporting member defines an inner fuel chamber and outer fuel chamber which communicates with each other through apertures. The suction opening is located at a side wall of the fuel gallery and the inlet opening is located at a bottom wall of the inner fuel chamber which is defined radially inside of the second supporting member. The fuel discharged into the outer fuel chamber through the suction opening is introduced into the inner fuel chamber through the apertures. A flow velocity of the fuel is decreased and a pressure pulsation reduction effect of the pulsation damper is surely achieved.

Abstract: A volume chamber is formed by a valve member, an inner peripheral wall of a tubular portion and a bottom portion of a stopper when the valve member is engaged with tubular portion. A communication passage communicates between the volume chamber and one of an intermediate passage of a valve body and a tertiary passage of the stopper. The communication passage is formed at a location, which is spaced from a contact surface between the tubular portion and the valve member by a first predetermined distance and is also spaced from a contact surface between the bottom portion and the first urging member by a second predetermined distance.

Abstract: A delivery valve is connected to a discharge passage, through which fuel in a compression chamber is discharged. The delivery valve is screwed to a mount hole formed in the cylinder. A communication passage is formed in a body to extend through the sidewall between a screwed part in which the mount hole and the body are screwed to each other, and a gasket. A small clearance is formed between an inner peripheral surface of the mount hole and an outer peripheral surface of the body. The communication passage provides communication between a fuel passage downstream of a valve seat member and the clearance. The clearance communicates with the suction chamber through a return passage formed in the cylinder.

Abstract: A fuel pump includes a housing having therein a suction passage and a pressurization chamber into which fuel from the suction passage flows, a plunger held in the housing to be reciprocable so as to pressurize the fuel flowing into the pressurization chamber, and a diaphragm device located in a suction chamber that is provided in the suction passage. The diaphragm device includes a pair of first and second diaphragms that are arranged to define an inner space therebetween and air-tightly sealed at its entire peripheries. A mass addition member may be attached to an inside surface of at least one of the first and second diaphragms, so that the first and second diaphragms with the mass addition member have different characteristic frequencies. Accordingly, pressure pulsation of the fuel in the suction chamber can be effectively reduced by the pulsation damper.

Abstract: A high pressure pump has a fuel passage and a pump chamber. Fuel flows into the pump chamber through the fuel passage. The high pressure pump includes a valve member and a plunger. The valve member is movable along a movable axis in a substantially axial direction of the valve member for controlling an amount of fuel flowing into the pump chamber through the fuel passage. The plunger is movable substantially along a movable axis in a substantially axial direction of the plunger. The plunger is capable of pressurizing fuel in the pump chamber to discharge fuel in the pump chamber. The movable axis of the valve member is displaced from the movable axis of the plunger substantially in parallel with each other.

Abstract: A fuel pump includes a pump housing having a compression chamber. A plunger is axially movable in the pump housing for pressurizing fuel in the compression chamber. A discharge valve is configured to open to supply fuel from the compression chamber to an internal combustion engine when pressure in the compression chamber is more than predetermined pressure. A fuel passage is configured to communicate a downstream of the discharge valve with an upstream of the discharge valve. An in-passage member is accommodated in the fuel passage. The in-passage member includes multiple members, which are combined to define a throttle portion for restricting fuel, which returns from the downstream of the discharge valve to the upstream of the discharge valve.

Abstract: A delivery valve is connected to a discharge passage, through which fuel in a compression chamber is discharged. The delivery valve is screwed to a mount hole formed in the cylinder. A communication passage is formed in a body to extend through the sidewall between a screwed part, in which the mount hole and the body are screwed to each other, and a gasket. A small clearance is formed between an inner peripheral surface of the mount hole and an outer peripheral surface of the body. The communication passage provides communication between a fuel passage downstream of a valve seat member and the clearance. The clearance communicates with the suction chamber through a return passage formed in the cylinder.

Abstract: A high pressure pump has a fuel passage and a pump chamber. Fuel flows into the pump chamber through the fuel passage. The high pressure pump includes a valve member and a plunger. The valve member is movable along a movable axis in a substantially axial direction of the valve member for controlling an amount of fuel flowing into the pump chamber through the fuel passage. The plunger is movable substantially along a movable axis in a substantially axial direction of the plunger. The plunger is capable of pressurizing fuel in the pump chamber to discharge fuel in the pump chamber. The movable axis of the valve member is displaced from the movable axis of the plunger substantially in parallel with each other.