The invention concerns a cam follower including a tappet having a cylindrical outer surface centered on a longitudinal axis (Y1) and adapted to slide in a housing surrounding the tappet, a pin extending between two opposite ends along a transverse axis (X1) perpendicular to the longitudinal axis (Y1), a roller element movable in rotation relative to the pin around the transverse axis (X1) and adapted to roll on a cam, and an antirotation member for preventing a rotation of the tappet around the longitudinal axis (Y1) in the housing. According to the invention, the antirotation member is one of overmolded onto the tappet and the tappet is overmolded onto the antirotation member. The invention also concerns an injection pump for a motor vehicle, each having a cam follower. The invention also concerns a method for manufacturing a cam follower.

A lifter rotation preventing structure includes a lifter body, a retainer and a biasing member. The lifter body is inserted into a sliding hole of a housing and reciprocated according to rotation of a cam. The lifter body has a peripheral wall slidable in a sliding hole and a partition wall partitioning an inside of the peripheral wall into a first space where the cam is located and a second space located opposite the first space. The retainer has a retainer body connected to an engaging member and a rotation preventing protrusion protruding from an outer periphery of the retainer body and fittingly extending through the peripheral wall. The rotation preventing protrusion has a distal end moved into a rotation preventing groove to prevent the lifter body from rotation. The biasing member interposed between the retainer body and the housing to bias the lifter body to the cam side.

An anti-rotation guide for a lifter in an overhead valve valvetrain. The anti-rotation guide includes a plug having two lobes connected through a neck region. A first lobe of the plug is held within a bore in the lifter. The bore forms an opening at the edge of the lifter through which the neck of the plug emerges. The bore in the lifter accommodates a first lobe of the plug that is wider than the opening in the edge of the lifter, whereby the plug is shaped to prevent its slipping from the lifter through the opening. The lifter reciprocates in a first bore in the cylinder head. The second lobe of the plug extends outward from the lifter into a second bore formed in the cylinder head and adjoining the first bore. The second lobe reciprocates in the second bore and limits rotation of the lifter.

A tappet assembly for use in translating force between a camshaft lobe and a fuel pump assembly via reciprocal movement within a tappet cylinder having a guide slot. The tappet assembly includes a bearing assembly having a shaft and a bearing rotatably supported by the shaft for engaging the lobe. An intermediate element has a shelf for engaging the fuel pump assembly, and a pair of arc-shaped bearing surfaces rotatably engaging the shaft when the bearing engages the lobe and the shelf engages the fuel pump assembly. The intermediate element includes a pair of lock apertures. The bearing assembly further includes a pair of shields supported on the shaft of the bearing assembly with the bearing interposed between the shields. The shields include a pair of opposing fingers for engaging the lock apertures so as to substantially retain the bearing assembly to the intermediate element and so as to substantially retain the shaft of the bearing assembly within the annular body in absence of engagement between the bearing and the camshaft lobe.

The present disclosure relates to fuel systems. Some embodiments of the teachings may include a fuel pump comprising: a pump piston having a longitudinal centerline; a camshaft with at least one cam; a roller tappet arranged between the pump piston and the cam; and a tappet body and a roller rotatably held on the roller tappet. The pump piston and the tappet body may be movement-coupled with regard to movements in directions parallel to the piston longitudinal centerline. The roller may be in contact with the cam. The longitudinal centerline may intersect a geometric axis of rotation of the roller. The tappet body defines a tappet body longitudinal centerline parallel to the piston longitudinal centerline. The tappet body longitudinal centerline, in a projected view oriented parallel to the geometric axis of rotation of the roller, runs with a lateral spacing to the piston longitudinal center line.

An object is to provide a roller lifter which can maintain a proper dimensional accuracy of an outer diameter. A shaft (25) rotatably supporting a roller (30) is inserted through a pair of opposed portions (21) and swaged to be fixed. A cylindrical portion (61) is disposed to be fixed at a relative position to the opposed portions (21). Upon rotation of a cam (90), the cylindrical portion (61) is reciprocated via the roller (30). The roller lifter (10) includes a first member (20) in which the shaft (25) is swaged to be fixed to the opposed portions (21) and a second member (60) separate from the first member (20) and couplable via a coupling member to the first member (20). The second member (60) includes at least the cylindrical portion (61).

A tappet assembly for use in translating force between a camshaft lobe and a fuel pump assembly via reciprocal movement within a tappet cylinder having a guide slot. The tappet assembly includes a bearing assembly having a shaft and a bearing rotatably supported by the shaft for engaging the lobe. An intermediate element has a shelf for engaging the fuel pump assembly, and a pair of arc-shaped bearing surfaces rotatably engaging the shaft when the bearing engages the lobe and the shelf engages the fuel pump assembly. The intermediate element includes a pair of lock apertures. The bearing assembly further includes a pair of shields supported on the shaft of the bearing assembly with the bearing interposed between the shields. The shields include a pair of opposing fingers for engaging the lock apertures so as to substantially retain the bearing assembly to the intermediate element and so as to substantially retain the shaft of the bearing assembly within the annular body in absence of engagement between the bearing and the camshaft lobe.

The cam follower roller device provides a tappet body extending along an axis, an insert mounted in the tappet body, a pin mounted at least on the insert and a roller mounted on the pin. The device further provides a spacer having a body mounted axially against the insert and with retaining means, cooperating with the insert for fixing the spacer to the insert.

The cam follower roller device provides a tappet body extending along an axis, an insert 18 mounted in the tappet body, a pin 14 mounted at least on the insert and a roller mounted on the pin. The device further provides a removable retaining plug carried by the tappet body and adapted to retain the insert relative to the body. A radial interference fit is provided between the retaining plug and the tappet body.

A roller tappet for a fuel unit pump of an internal combustion engine is provided with a roller tappet bore for inserting the roller tappet within the internal combustion engine. The roller tappet includes a roller tappet body having a body longitudinal axis for connecting the roller tappet to a reciprocating element of the fuel unit pump. A cam roller contacts a cam lobe of a rotatable shaft of the internal combustion engine. The cam roller is rotatably mounted to the roller tappet body around a cam roller rotation axis. The external surface of the roller tappet body is configured to allow tilting of the roller tappet within the roller tappet bore for aligning the roller tappet with respect to the cam lobe of the rotatable shaft.