A plunger (1) for a high-pressure fuel pump is proposed, having a housing (2) which is similar to a tube and in the drive-side annular face (3) of which two flats (5) lie diametrically opposite one another which are indented from an outer shell (4) of the housing (2) and in which a pin (7) is mounted which supports a roller, wherein an inner shell (8) of the housing (2) is penetrated axially below the roller by a separate bridge piece (9), the lower face (10) of which acts as a rest for a pump piston in the case of an output-side annular face (11) of the housing (2), wherein the bridge piece (9) is fixed against rotation about an axial line of the housing (2) and is configured as a thick-walled longitudinal beam, with the result that an area (13) in the manner of a cylindrical segment remains between the longitudinal walls (12) of said longitudinal beam and the inner shell (8) of the housing (2), wherein, in order to fix the bridge piece (9) against rotation about the axial line of the housing (2), in the circumferential section of the inner shell (8) of the housing (2), in a first transverse wall (14) of the bridge piece (9), at least one projection (15) protrudes from one of the components (8, 14), which projection (15) is seated in a respectively complementary recess (16) of the respective other one of the components (14, 8).

A lifter includes a roller caused to abut against a cam thereby to be pressed and a lifter body rotatably supporting the roller and housed in a guide hole of a lifter guide so as to be reciprocable in the guide hole. The lifter body includes a cylindrical part and a rotation stopper. The cylindrical part has an outer periphery formed into a cylindrical shape such that the outer periphery is slidable on an inner periphery of the guide hole. The cylindrical part has one of two axial ends, the one end being formed with a skirt covering the roller. The rotation stopper is formed to protrude outward from the other axial end of the cylindrical part, the other axial end being located opposite a side where the skirt is located. The rotation stopper prevents the lifter body from being rotated about an axis thereof relative to the lifter guide.

The invention concerns a cam follower providing 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, and a roller element movable in rotation relative to the pin around the transverse axis and adapted to roll on a cam. The tappet is made of a composite material integrating at least one dry lubricant released at the cylindrical outer surface when the cam follower is in operation. The invention also concerns a valve actuator for a motor vehicle, providing such a cam follower. The invention also concerns a method for manufacturing such a cam follower.

An internal combustion engine having a valve lifter assembly is disclosed. The internal combustion engine comprising an engine head having at least two wells adapted to receive at least one valve lifter, the at least one valve lifter includes a flat surface, at least one spacer installed within the engine head having a first surface, a hollow portion, and a second surface, the first surface is tapered with respect to a vertical axis of the at least one spacer, and a tie-bar plate for coupling the at least one spacer using head bolts. The at least one spacer and the at least one valve lifter are operatively arranged during operation in such a way that the flat surface of the at least one valve lifter faces the first surface of the at least one spacer to prevent rotation of the at least one valve lifter.

An internal combustion engine having a valve lifter assembly is disclosed. The internal combustion engine comprising an engine head having at least two wells adapted to receive at least one valve lifter, the at least one valve lifter includes a flat surface, at least one spacer installed within the engine head having a first surface, a hollow portion, and a second surface, the first surface is tapered with respect to a vertical axis of the at least one spacer, and a tie-bar plate for coupling the at least one spacer using head bolts. The at least one spacer and the at least one valve lifter are operatively arranged during operation in such a way that the flat surface of the at least one valve lifter faces the first surface of the at least one spacer to prevent rotation of the at least one valve lifter.

There is provided a cylinder head of an engine. The cylinder head includes cylindrical parts for lash adjustors into which the lash adjustors are inserted and cylindrical parts for fuel injection valves into which the fuel injection valves are inserted. An outer periphery of each of the cylindrical parts for the lash adjustors is connected to a sidewall of the cylinder head, which is disposed above intake ports communicating with a combustion chamber and each of the cylindrical parts for the fuel injection valves is disposed below the cylindrical parts for the lash adjustors. A lower end portion of each of the cylindrical parts for the lash adjustors is connected to an upper part of each of the cylindrical parts for the fuel injection valves by a reinforcement part.

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 mechanical system, comprising a tappet including a body, a support element defining two bores centered on a first axis, a pin comprising two opposite ends each adapted to be fitted in one of the two bores, and a roller element positioned between the two bores along the first axis and movable in rotation relative to the pin around the first axis. The support element is distinct from the body and fixed thereto, and the support element also comprises at least one antirotation device integrally formed thereto. The mechanical system can be integrated into an injection pump and/or a valve actuator.

A cam follower roller device, in particular for a fuel injection pump of an internal combustion engine, includes a tappet with a sleeve having an opening for partially accommodating a roller, a roller mounted rotatably in the sleeve and having a portion which protrudes axially from the opening of the sleeve provided to cooperate with a cam, and a roller support body housed in the sleeve. The roller includes a cylindrical spindle and a cylindrical body, the ends of the spindle projecting from the lateral faces of the body. The support body includes supports open towards the opening of the sleeve and supporting the ends of the spindle.

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.