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).

In a tappet-driven single piston pump, piston side loads caused by return spring out-of-squareness are eliminated by effectively piloting the piston return spring, preferably the associated spring seat, by the tappet, thereby allowing the tappet to bear the spring side load. The piston engages and is returned by the spring seat, but radial clearance between the piston and spring seat is greater than radial clearance between the spring seat and tappet, thus eliminating side loading imparted to the piston. The spring seat can be considered a piston retainer, in which the piston is not closely attached to the retainer but instead exhibits a predefined radial clearance greater than the piloting clearance between the retainer and the tappet.

A fuel pump assembly includes a fuel pump. The fuel pump includes a camshaft having a cam lobe. The camshaft is configured to rotate. The fuel pump includes a first cam roller and a second cam roller disposed about an outer surface of the cam lobe, a first pumping assembly configured to interact with the first cam roller, and a second pumping assembly configured to interact with the second cam roller. The second pumping assembly is offset from the first pumping assembly. The fuel pump further includes a housing configured to support the camshaft, the first cam roller, the second cam roller, the first pumping assembly, and the second pumping assembly.

A fuel pump assembly includes a fuel pump. The fuel pump includes a camshaft having a cam lobe. The camshaft is configured to rotate. The fuel pump includes a first cam roller and a second cam roller disposed about an outer surface of the cam lobe, a first pumping assembly configured to interact with the first cam roller, and a second pumping assembly configured to interact with the second cam roller. The second pumping assembly is offset from the first pumping assembly. The fuel pump further includes a housing configured to support the camshaft, the first cam roller, the second cam roller, the first pumping assembly, and the second pumping assembly.

A reciprocating pump comprising a roller tappet and a pump plunger that is operatively connected to the roller tappet, wherein the roller tappet has a roller support, a roller and a pin, wherein a first bearing eye and a second bearing eye are formed in the roller support, wherein the pin is mounted in the first bearing eye and in the second bearing eye, wherein the roller is arranged on the pin in a rotatable manner, and wherein the pin is mounted more flexibly in the first bearing eye than in the second bearing eye.

A cam follower roller device having a tappet body extending along a longitudinal axis and defining a tappet bore, a pin centered on a transverse axis and providing two opposite ends arranged in through-holes transversally facing one another on tappet body, and a roller rotatably mounted on the pin around said transverse axis. The tappet body is a machined metal tube or bar and is provided with a radial plate that is securely fixed within tappet bore, said radial plate being dedicated to support a longitudinally movable piston.

A roller tappet assembly for a reciprocating pump comprises: a tappet body; a pin element comprising: first and second opposing end portions that engage respective formations in the tappet body to retain the pin element, and a bearing portion, extending between the first and second end portions, for supporting a cam rider arrangement. The cam rider arrangement is supported on the bearing portion of the pin element so that, in use, the reciprocating pump is cyclically loaded and unloaded as an outer surface of the cam rider arrangement interfaces with a rotating camshaft. At least one of: the bearing portion of the pin element; and/or an inner surface of the cam rider arrangement; comprises one or more recessed formations for supporting hydrodynamic lubrication between the cam rider arrangement and the pin element as the bearing portion bends during the loading cycle.

A high-pressure pump including a drive shaft (2) supported about an axis of rotation (26) and having at least one cam (3). The pump includes at least two pistons (5); at least two cylinders (6) supporting the pistons (5); wherein the pistons (5) have longitudinal axes (16) oriented at an angle to each other in a projection of the piston longitudinal axes (16) in the direction of the axis of rotation (26) onto a fictitious projection plane perpendicular to the axis of rotation (26). Each of the pistons (5) is supported on a shaft rolling surface (4) of the drive shaft (2) having the at least one cam (3) indirectly by means of a respective supporting element (14) having a supporting rolling surface (15), such that a translational motion can be performed by the pistons (5) as the result of a rotational motion of the drive shaft (2), wherein the piston longitudinal axes (16) have an axial distance in the direction of the axis of rotation (26).

A mechanical system forms a cam follower or a rocker arm. The mechanical system comprises: a support element, a pin extending between two opposite ends along a first axis and supported by the support element, and a roller adapted to receive the pin. The roller being mounted on pin, movable in rotation relative to the pin around the first axis and adapted to roll on a cam. The support element comprises two separate parts, generally semi-cylindrical, each having a contact face, in contact with one other, and a holding feature for maintaining parts assembled together.

A fuel pump assembly includes a fuel pump. The fuel pump includes a camshaft having a cam lobe. The camshaft is configured to rotate. The fuel pump includes a first cam roller and a second cam roller disposed about an outer surface of the cam lobe, a first pumping assembly configured to interact with the first cam roller, and a second pumping assembly configured to interact with the second cam roller. The second pumping assembly is offset from the first pumping assembly. The fuel pump further includes a housing configured to support the camshaft, the first cam roller, the second cam roller, the first pumping assembly, and the second pumping assembly.