A pump unit for supplying fuel, preferably diesel oil, to an internal combustion engine has at least two cylinders (10), which are formed in at least one head (9), are slidingly engaged by respective pistons (13), and communicate hydraulically with respective fuel inlets (11) in the cylinders (10) via respective interposed intake valves (15) provided with respective valve bodies (16) incorporated in the head (9); the inlets (11) of all the cylinders (10) being closed by a single cover (33) fixed to the head (9).

Methods and systems are provided for a gear driven diesel fuel injection pump of an engine. In one example, a front end of an engine includes an idler gear in meshing engagement with a first end of a crankshaft and a fuel pump drive gear in meshing engagement with the idler gear. The front end of the engine may further include a fuel pump, where an input shaft of the fuel pump is directly coupled to the fuel pump drive gear.

A follower mechanism including an outer cup having a substantially cylindrical side wall, an annular lip portion disposed at a first end of the side wall, and an annular ledge disposed on the side wall, the annular ledge being disposed in a plane that is transverse to a longitudinal center axis of the follower mechanism. An inner cup includes an annular lip extending outwardly therefrom and a pair of shaft apertures, and is disposed in the outer cup so that the lip abuts the annular ledge of the outer cup and is non-rotatably fixed thereto by the annular lip of the outer cup which abuts the lip of the inner cup. A shaft is received in the shaft apertures, and a roller follower is rotatably received on the shaft such that a portion of the roller follower extends axially outwardly beyond the annular lip portion of the outer cup.

A fluid system such as a fuel system includes a fluid supply and a pump coupled between the fluid supply and a plurality of fluid delivery devices. The pump can be a cryogenic pump such as for liquefied natural gas, with valve mechanisms to control hydraulic actuation of a piston used to pump the liquefied natural gas. An electrically conductive coil is coupled with the piston. Related methodology is disclosed.

Provided is a high pressure fuel pump including: a body formed in a side surface thereof with a discharge hole; a pressurizing device for generating a suction force for sucking fuel supplied from a fuel tank and a pressurizing force for pressurizing the fuel at a high pressure; a seal carrier coupled to a lower portion of the body and coupled with the pressurizing device; a flow control valve coupled to one side of the body, for controlling a supply flow rate and a discharge pressure of the fuel; and a pressure relief valve for relieving an abnormal high pressure by transferring a part of discharged fuel to a low pressure space formed in the lower portion of the body when the abnormal high pressure exceeding a preset pressure limit is generated in a fuel supply system for supplying the fuel discharged through the discharge hole to an injector.

A mechanical system that forms a cam follower or a rocker arm. The mechanical system includes a support element, a pin extending between two opposite ends along a first axis, and a roller mounted on the pin, movable in rotation relative to the pin around the first axis and adapted to roll on a cam. The support element further comprises an insert having holding members supporting the pin ends, provided with cut-outs having a shape complementary to the shape of the pin-ends, for assembling pin with insert by quarter-turn around the first axis. The pin ends each have a flat surface and an external surface. A first dimension of each pin end, measured perpendicularly to the flat surface, between the flat surface and the external surface of the pin end, is higher than half the outer diameter of the pin ends.

A high pressure pump for complex injection engines is provided. A body of the high pressure pump includes a first flow path that transports the low pressure fuel flowing in through the low pressure fuel inlet and a low pressure fuel storage chamber that is disposed in a lower portion of the body to store the low pressure fuel transported from the first flow path. A second flow path transports the low pressure fuel stored in the low pressure fuel storage chamber and a flow control valve is disposed over the low pressure fuel storage chamber to discharge the low pressure fuel, transported through the second flow path, to the pressure unit or the damper disposed in an upper portion of the body based on an opening or closing operation. A low pressure fuel outlet discharges the low pressure fuel, transported through the damper, to a low pressure fuel rail.

An apparatus and a method for controlling a flow control valve for a high-pressure fuel pump include: a pressure sensor for fuel in a delivery pipe; a control unit for controlling an operation of a flow control valve by controlling a current applied to a coil; a power switching unit for supplying or blocking driving power supplied to the flow control valve based on a control signal of the control unit; and a current adjustment unit electrically connected/disconnected with the flow control valve by the power switching unit to reduce a current supplied to the flow control valve when the current adjustment unit is connected with the flow control valve. Therefore, a noise and a vibration by collision between the plunger and the core upon closing the flow control valve may be attenuated by adjusting a current amount applied to the coil.

A high-pressure fuel pump includes a drive shaft, and a vane pump and a plunger pump which are driven by the drive shaft. The vane pump is configured to supply pre-pressurized fuel to the plunger pump. The drive shaft includes a cam configured to drive a piston rod of the plunger pump such that the plunger pump alternately executes a fuel suction stroke and a fuel discharge stroke. The drive shaft further includes a shaft portion for driving a rotor of the vane pump. The vane pump is configured such that for each fuel suction stroke of the plunger pump the vane pump provides a fuel supply cycle that is advanced by a phase angle relative to the fuel suction stroke.

A mechanical system that forms one of a cam follower or a rocker arm. The mechanical system comprises a support element including a first body portion and a second body portion, a pin extending between two opposite ends along a first axis and supported by the first body portion of the support element, and a roller mounted on pin, movable in rotation relative to the pin around the first axis and adapted to roll on a cam. The mechanical system further comprises a spacing element comprising a first body portion connected to the second body part of the support element and a second body portion adapted to be supported by a movable support.