The fuel injection valve has a hydraulic control device for controlling the axial movement of the injection valve member. The stem of the intermediate valve member of mushroom-shaped configuration of the intermediate valve is guided in the guide recess of the intermediate part. In the open position, the intermediate valve member opens up a second connection between a high-pressure fuel inlet and a valve chamber and, in the closed position, the intermediate valve member shuts off the second connection between the high-pressure fuel inlet and the valve chamber. In the closed position of the intermediate valve member, the head of the intermediate valve member lies with a side facing toward the intermediate part against the intermediate valve seat via a first sealing surface, which runs around the stem or the guide recess at a first radial spacing so as to form a first annular sealing surface which is continuous in the circumferential direction.

There are provided a laminated piezoelectric element in which a stress applied to an interface between a cover layer and a stacked body is reduced, and an injection device and a fuel injection system provided with the laminated piezoelectric element. A laminated piezoelectric element includes a stacked body in which piezoelectric layers and internal electrode layers are alternately laminated; and a cover layer disposed so as to surround a side face of the stacked body, and the cover layer has a two-layer structure with an annular boundary when viewed in a section perpendicular to a stacking direction of the stacked body.

A characteristic determining device is provided which determines fuel injection characteristics of a plurality of fuel injectors for an internal combustion engine. The characteristic determining device includes a pressure sensor and a plurality of pipes each of which connects between the pressure sensor and one of the fuel injectors. The pressure sensor is designed to have a plurality of pressure inputs from the respective fuel injectors through the pipes and outputs a signal indicative of a level of pressure in each of the fuel injectors. The characteristic determining device analyzes the signals from the first pressure sensor to determine the fuel injection characteristics of the respective fuel injectors. These arrangements result in a simplified structure of the characteristic determining device and a decreased manufacturing cost thereof.

Provided is a fuel supply pump capable of improving welding quality while securing a function of a valve body. A fuel supply pump of the present invention includes a regulating member (discharge valve stopper 84) that guides movement of a valve body (discharge valve 82), a main body portion (body 1) provided with a valve chamber (discharge valve chamber 1d) that houses the regulating member, a sealing member (plug 85) that seals the valve chamber, and a welded portion (welded portion 86) that fixes the sealing member to the main body portion. An annular space portion (annular space portion 60) along an outer periphery of the regulating member is formed between the welded portion and the regulating member. The regulating member includes a positioning portion (fitting portion 84a) for positioning with respect to the main body portion on a side opposite to the sealing member, and a gap forming portion (gap forming portion 84c) forming an annular gap (annular gap 63) between the gap forming portion and the main body portion, and the annular gap allows a space on a side of the positioning portion in the valve chamber and the annular space portion to communicate with each other.

An injector apparatus (110) for injecting fluid under pressure into an associated chamber (132), the apparatus including a body (112), a first piston (114) moveable in the body, the first piston defining a first working area facing an associated chamber (132), a high pressure piston (18,118) defining a high pressure working area facing a high pressure chamber (19), the first working area being greater than the high pressure working area, the first piston (114) being operable to compress fluid in the high pressure chamber using the high pressure piston (118), the injector apparatus (110) having a first configuration having a first ratio of the first working area to high pressure working area and having a second configuration having a second ratio of the first working area to the high pressure working area, wherein a first ratio is different from the second ratio.

An injector apparatus (110) for injecting fluid under pressure into an associated chamber (132), the apparatus including a body (112), a first piston (114) moveable in the body, the first piston defining a first working area facing an associated chamber (132), a high pressure piston (18,118) defining a high pressure working area facing a high pressure chamber (19), the first working area being greater than the high pressure working area, the first piston (114) being operable to compress fluid in the high pressure chamber using the high pressure piston (118), the injector apparatus (110) having a first configuration having a first ratio of the first working area to high pressure working area and having a second configuration having a second ratio of the first working area to the high pressure working area, wherein a first ratio is different from the second ratio.

The invention relates to a fuel injector for injecting fuel under high pressure, comprising a housing (1) equipped with a nozzle needle (10) which can be moved in a longitudinal direction and a seal surface (11) of which opens and closes one or more injection openings (13), fuel being injectable via said injection openings. A control chamber (20) which can be filled with fuel exerts a hydraulic pressure onto the nozzle needle (10) in the closing direction thereof, wherein the pressure in the control chamber (20) can be influenced by a control valve (22) in that the control valve (22) opens and closes a hydraulic connection between the control chamber (20) and a low-pressure chamber (21). The control valve (22) comprises a solenoid armature (23) which interacts with a control valve seat (26) in order to open and close the hydraulic connection, said solenoid armature (23) being radially guided in the housing (1) on the exterior (33) of the solenoid armature.

Provided is a discharge valve mechanism capable of improving responsiveness when a discharge valve is opened, and a high-pressure fuel supply pump including the discharge valve mechanism.

A discharge valve mechanism 500 includes a valve seat portion 51 having a primary-side flow path, a valve body 52 which can be seated on and separated from the valve seat portion 51, and a guide portion 542a which is formed to be slidable on an outer surface of the valve body 52 and guides movement of the valve body 52 in a contacting/separating direction with respect to the valve seat portion 51. The guide portion 542a includes a portion in which a gap from the outer surface of the valve body 52 is set to a predetermined value or less. A first secondary-side flow path 545 which allows an internal space 541a on an upstream side of the guide portion 542a to communicate with an external flow path 2g is formed to allow the fluid to flow out to a side in a moving direction of the valve body 52, and a second secondary-side flow path 546 which allows an internal space 543a on a downstream side of the guide portion 542a to communicate with the external flow path 2g is formed to allow the fluid to flow out to the side in the moving direction of the valve body 52.

Systems and methods for supplying lubricating oil to a high-pressure fuel pump of an engine fuel system. In one embodiment, a system may include a plurality of channels routing lubricating oil to a gear system and drive shaft of a pump without flowing an entire volume of the lubricating oil through a cavity of the drive shaft.

With a simple configuration, responsiveness between an electronic control unit and a load drive circuit is monitored without deteriorating characteristics of the load drive circuit. The load drive circuit according to the present invention diagnoses an abnormality in responsiveness of a switch element that drives a load based on a drive command of the switch element and a signal at an output terminal of the switch element.