A metering valve supplies fuel to and block fuel from a pressurizing chamber by moving a valve body by switching between energization and de-energization of an electromagnetic unit. An energization control unit performs a valve closing control and a valve opening control to reduce operating sound in one opening and closing period in which the valve body opens and closes. A time control unit controls, on determination that the energizing period of the electromagnetic unit exceeds the upper limit value, a moving speed of the valve body when the valve body moves to a valve closing side, such that the energization period of the electromagnetic unit in the one opening and closing period does not exceed the upper limit value, thereby to cause the energization control unit to perform both the valve closing control and the valve opening control in the one opening and closing period.

The disclosure relates to a tappet for acting on a pump piston of a high-pressure fuel pump of an internal combustion engine. The tappet includes a tubular housing, and at the upper annular end face of the tubular housing, two surfaces which are indented relative to the outer casing of the housing and comprise a pin that supports a cam roller, lie diametrically opposite each other. An upper end face of a transverse beam lies against axial inner end faces of the two surfaces. A transverse beam lower end face, which faces a lower annular end face of the housing, is provided with a pin, which protrudes from the housing and is surrounded by a spring plate supported against the inner casing of the housing. A sleeve-like inner collar of the spring plate guides the unstepped pin.

The purpose of the present invention is to increase the pressure of fuel while reducing an increase in the maximum lift amount of a cam and deterioration of a fuel injection ability. This cam for use in a fuel injection pump that increases the pressure of fuel supplied into a fuel supply chamber by an axial movement of a plunger. The cam includes a first cam surface that causes an increase rate of an axial speed of the plunger when the cam rotates at a constant speed, in a pre-stroke period until the plunger increases the pressure of the fuel in the fuel supply chamber, to be a first increase rate, and a second cam surface that causes the increase rate of the axial speed of the plunger when the cam rotates at the constant speed, in a pressure increasing period that is a period from a start of increasing the pressure of the fuel in the fuel supply chamber by the plunger, to be a second increase rate, wherein the first increase rate is set higher than the second increase rate.

A tappet, which may be a pump actuator, comprises a body that is a contiguous piece of ferrous metal. The body comprises an outer shell and an inner side. The outer shell is case-hardened to a first hardness, and the inner side comprises a second hardness less than the first hardness. The outer shell comprises a bore-running surface and an outward projection that is operative as an anti-rotation guide feature and projects outwardly from the bore-running surface. The body further comprises two parallel planar surfaces disposed at a drive-input end of the body and an axle hole defined in each of the two parallel planar surfaces. The tappet further comprises an axial support pin mounted through the axle hole of each of the two parallel planar surfaces and a cam follower mounted to the body via the axial support pin.

A fuel injection pump includes: a tappet configured to reciprocate by rotation of a cam; a cylinder that supports the tappet to reciprocate; and a plunger configured to reciprocate with the tappet. The tappet includes: a tappet body supported by the cylinder to reciprocate; a pin supported on both sides in an axial direction of the pin by the tappet body; a roller rotatably fitted to an outer peripheral side of the pin; a washer disposed between at least one end surface of the roller in the axial direction and an inner peripheral surface of the tappet body. The washer has at least one protrusion to be in contact with a stopper of the tappet body in either of two rotational directions.

A cam follower, comprising: a tappet which includes two flanges provided with opposite holes centered on a transverse axis; a pin extending along the transverse axis between two opposite ends received in the opposite holes; and a roller movable in rotation relative to the pin around the transverse axis and adapted to roll on a cam. Each of the opposite holes is provided with: an open portion for mounting the pin by translation in a first direction perpendicular to the transverse axis, a cylindrical portion for supporting the pin along the first direction and a plane portion for retaining the pin along the transverse axis during transport and mounting of the cam follower. A method includes steps for manufacturing such a cam follower.

A pump unit for feeding fuel, preferably diesel fuel, to an internal combustion engine; the pump unit (1) comprising: a head (4) inside which a cylinder (12) extending along an axis (A1) is formed; a pumping piston (5) extending along the axis (A1) and slidingly coupled with the cylinder (12); a through-hole (13) which extends from the cylinder (12) towards the outside of the pump unit (1); an intake chamber (8) communicating with the cylinder (12) via the hole (13); an intake valve (7) which controls the flow of fuel from the intake chamber (8) to the hole (13); a cap (23; 123; 223) which is connected to the head (4), is arranged on the opposite side to the pumping piston (5) and can be selectively fixed along an outer surface (25) of the head (4) so as to close the intake chamber (8) on one side.

A fuel pump for a direct injection system and having: a main body; a pumping chamber; a piston, which is mounted in a sliding manner on the inside of the pumping chamber; an intake duct, which ends in the pumping chamber; an intake valve, which is arranged along the intake duct; and a flow rate adjustment device provided with a control rod which is coupled to the intake valve and with an electromagnetic actuator which is configured to axially move the control rod. The flow rate adjustment device has a containing element, which houses the electromagnetic actuator, has an open end facing the intake valve, and ends with a “U”-shaped rim which has an outer ring which is arranged around the containing element at a given distance from a cylindrical wall of the containing element. An annular weld (22) is obtained between the main body and the outer ring of the “U”-shaped rim.

A roller for a mechanical fuel pump assembly includes an elongate body extending from a first axial end to a second axial end of the elongate body over an overall length of the elongate body. The elongate body defines an effective length that is less than the overall length. The elongate body defines a uniform circular cross section over a second length of the elongate body. The second length is 75 to 90 percent of the effective length and the second length extends between a first plane and a second plane. A first area of reduced cross section extends axially outward from the first plane to a third plane located axially inward of the first axial end; and a second area of reduced cross section extends axially outward from the second plane to a fourth plane located axially inward of the second axial end.

Pump, in particular a high-pressure fuel pump, having at least one pump element (10) which has a pump piston (12) which is driven in a reciprocating movement by way of a drive shaft (14) with at least one cam (16; 160) and delimits a pump working chamber (24) which can be filled with delivery medium via an inlet valve (26) during the suction stroke of the pump piston (12). The at least one cam (60; 160) of the drive shaft (14) is a multiple cam with a plurality of cam delivery regions (16a, 16b) for the delivery strokes of the pump piston (12), or a plurality of single or multiple cams (160) with in each case at least one cam delivery region (160a, 160b) for the delivery strokes of the pump piston (12) are provided which are arranged next to one another in the direction of the rotational axis (15) of the drive shaft (14). The cam profiles of the cam delivery regions (16a, 16b) of the at least one multiple cam (16) or the cam profiles of the cam delivery regions (160a, 160b) of the single cams (160) are of different configuration.