A high-pressure oil pump roller tappet, used for automobile fuel injection system, mounted between the driving cam and the tappet. The roller tappet includes a shell, a holder, a roller, and a pin. Planes A are arranged on both sides of the seam on lateral sides of the shell. Holes I are arranged at symmetrical positions on two planes A. Holes II are arranged on symmetrical positions on vertical plates. The roller is located in the middle of the pin. Welding has no requirement on the thickness of the plate. The weight can be controlled effectively, reducing inertia force, friction, and wear, improving engine efficiency. The shell and holder are designed as being separate, ensuring that the shell subjects to lateral force as little as possible when the holder subjects to a force, such that the shell is less likely to vibrate. Thus, the shell avoids the abrasion.

Fuel pump for a direct injection system provided with a common rail. The fuel pump has a pumping chamber defined in a main body; a piston which is mounted in a sliding manner inside the pumping chamber to cyclically vary the volume of the pumping chamber; an intake channel which originates from a wall of the pumping chamber; an intake valve which is coupled to the intake channel; a delivery channel which originates from a wall of the pumping chamber; a delivery valve which is coupled to the delivery channel; and an actuating spring which has a plurality of turns having a pitch that varies between the turns and that is coupled to the piston so as to push the piston towards a maximum volume or minimum volume position of the pumping chamber.

Disclosed is a pump, in particular a high-pressure fuel pump, comprising at least one pump element (10) that has a roller tappet (20) inside which a roller (42) is rotatably mounted on a bearing bolt (44) by means of a bearing sleeve (46), said roller (42) rolling off a cam (22) of an input shaft (24). The bearing sleeve (46) is made of a plastic material, especially polyether ether ketone (PEEK) or polyphthalamide (PPA).

An axial piston pump has a fluid inlet, a fluid outlet, and a rotatable, one-piece piston housing carrying one or more pistons movable within one or more respective sleeves formed by the housing. A circumferential row of fixed field members is mounted to the housing at a mounting location formed by the housing, the mounting location being radially outward of the sleeve(s). The pump further has a stator surrounding the piston housing and including a circumferential row of armature windings such that the piston housing and the stator form an electro-magnetic motor operable to rotate the piston housing, and a swashplate engaged with the piston(s) such that rotation of the piston housing relative to the swashplate around an axis of rotation produces reciprocating movement of the piston(s) for the pressurisation of fluid received into the sleeve(s) from the fluid inlet and then discharged from the sleeve(s) to the fluid outlet.

The present disclosure provides a high-pressure fuel pump including a barrel unit, a plunger, and a camshaft assembly having an eccentric cam lobe including a surface of the lobe. A follower is provided between the plunger and the surface of the lobe of the camshaft assembly to facilitate translation between the rotational movement of the camshaft assembly to axial movement of the plunger. The follower includes arcuate surfaces configured to mate with corresponding arcuate surfaces of the lobe of the cam shaft assembly and the plunger, respectively.

A piston pump, in particular a high-pressure fuel pump for an internal combustion engine, includes a pump housing, a pump piston, and a delivery chamber that is delimited at least by the pump housing and the pump piston. The piston pump further includes a seal configured to seal the delivery chamber and a separate guide element configured to guide the pump piston. The seal and the guide element are arranged between the pump piston and the pump housing. The seal is formed as a plastic ring with a substantially sleeve-shaped base portion.

A fuel pump includes a camshaft that rotates in accordance with operation of an engine and a tappet provided in contact the camshaft. An ECU includes an angle determination unit configured to determine whether a rotation angle from a start of rotation of the camshaft when starting the engine is under a predetermined angle required for forming an oil film on a sliding portion of the tappet, and a control unit configured to, when the rotation angle from the start of rotation of the camshaft is determined to be under the predetermined angle, execute a limit process including at least one of limiting a fuel discharge pressure of the fuel pump or limiting a rotation of the camshaft.

A cam follower assembly is provided including an improved lubricant flowpath. The assembly includes a generally cylindrical housing including an annular groove adapted to be in communication with a lubricant gallery in an engine block or cylinder head. An axial end of the housing includes skirt portions including openings, and one of the skirt portions includes a first recessed section indented from an outer lateral surface of the housing and extending axially between the annular groove and a respective one of the openings. A pin is mounted in the openings of the skirt portions and has a second recessed section indented from an outer lateral surface of the pin that extends to at least one of the ends of the pin. The second recessed section is in communication with the first recessed section, and a cam roller supported on the pin.

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).

An object of the present invention is to obtain a high pressure fuel supply pump capable of reducing pressure pulsation that occurs in a low pressure pipe, preventing damage to the low pressure pipe, or reducing noise due to vibrations of the low pressure pipe. The present invention provides a high pressure fuel supply pump of a type in which, from a fuel suction port connected to a low pressure pipe provided upstream of a fuel, a low pressure passage, an electromagnetic suction valve driven by an electromagnetic force, a pressurizing chamber in which the volume thereof is increased or reduced by a plunger that is reciprocatingly moved by being guided by a cylinder, and a discharge valve provided at an outlet of the pressurizing chamber are sequentially arranged, a fuel is sucked to the pressurizing chamber through the electromagnetic suction valve, the amount of a part of the fuel, which is sucked to the pressurizing chamber, to be returned to the low pressure passage side is adjusted so that the amount of the fuel to be discharged through the discharge valve is controlled, and the high pressure fuel supply pump includes a backflow suppression mechanism for suppressing backflow of fuel from the fuel from the fuel suction portion to the low pressure pipe side.