The disclosure relates to a roller tappet for a high-pressure fuel pump. The roller tappet includes a housing that accommodates a cam contact roller next to a drive-side annular face of the housing. A bridge piece sits on an inner lateral surface of the housing, after the cam contact roller, as viewed from the drive-side annular face. An outer end face of the bridge piece has a rest for a pump piston. A separate adapter bolt protrudes from the rest beyond the output-side annular face of the housing; an end face of the adapter bolt, remote from the bridge piece, serves as a direct rest for the pump piston. An annular disc sits next to the output-side annular face of the housing, and the bore of said annular disc surrounds and retains the adapter bolt.

A roller lifter includes a lifter body having a cylindrical peripheral wall with a sliding surface on an outer periphery thereof and a roller rotatably mounted via a shaft member on the lifter body and brought into contact with a cam. The sliding surface is reciprocally slid in a sliding hole of a lifter guide. The peripheral wall has a thicker part in a part thereof in a circumferential direction. The thicker part is shaped such that a thickening part is annexed to an outer wall part formed continuously with a constant thickness in the circumferential direction. The thicker part is formed with a rotation stopper bulging outward. The rotation stopper enters a guide groove communicating with the sliding hole of the lifter guide.

The device comprises a casing portion that has an open axial end and that has two main holes, respectively for fluid feed and for fluid discharge. Said holes open out in an inside axial face of the casing portion, respectively via a first main orifice and via a second main orifice that are disposed in succession in the direction going away from the open axial end. The inside axial face has first, second, and third sealing inside bearing surface arrangements, respectively situated between the open axial end and the first main orifice, between the two main orifices, and beyond the second main orifice. At least two of the three arrangements are staggered inside arrangements, each of which comprises two axial bearing surfaces that are staggered relative to each other, and that are separated by a shoulder facing towards the open axial end.

A roller assembly, comprising a roller shoe having a bottom surface, and a groove at the bottom surface, the groove having a semicircular portion and a straight portion extending from the semicircular portion, the semicircular portion having a first diameter and the straight portion having a first width, and a cylindrical roller positioned in the roller shoe groove, the cylindrical roller having a second diameter, wherein the first width is greater than or equal to the first diameter and the second diameter is less than the first width.

The present invention provides a cylinder liner retainer system with a torque multiplier and associated method to quickly release an existing cylinder liner and reinsert a new cylinder liner as a replacement.

This plunger pump includes a pressurization chamber that has a tubular inner circumferential wall and a plunger that has a substantially cylindrical outer circumferential surface. The inner circumferential wall has, in a part thereof in a circumferential direction about an axis of the plunger, a suction opening, which communicates with the pressurization chamber and is for introducing a fuel into the pressurization chamber. The inner circumferential wall is formed with an enlarged gap portion having a larger dimension than a dimension, at a position of the suction opening, from the outer circumferential surface of the plunger to an inner circumferential surface of the inner circumferential wall along a radial direction of the plunger, in at least a part of the inner circumferential wall at a position away from the position of the suction opening in the circumferential direction.

A plunger pump is provided which comprises: a pump body having a cylinder hole with an expanded diameter section; a plunger defining, together with the lid member, a pump chamber; and a coiled spring disposed within the expanded diameter section. The coiled spring includes: an effective winding section; a lid-side seat winding section; and a plunger-side seat winding section. The lid-side seat winding section has an outer diameter larger than an outer diameter of the effective winding section, and the plunger-side seat winding section has an outer diameter smaller than an outer diameter of the plunger. With this configuration, the coiled spring within the pump chamber can have increased stability, and can be located in the center of the pump chamber.

A guide ring of a pump portion is fixed in a cylinder containing hole in such a manner that a distal end of a first end portion thereof is positioned in a cam containing hole on an upper side with respect to an opening edge of the cylinder containing hole.

A cam follower including a plunger intended to execute a reciprocating movement in an exterior body. The plunger includes a plunger body having a cylindrical exterior surface, an anti-rotation device extending radially beyond the cylindrical exterior surface of the pusher body and engaging via a matching structure in the exterior body, a roller providing the contact with a cam, and a sleeve rotatably supporting the roller in the plunger body. The plunger body includes at least one lateral bore and the sleeve is inserted in the bore. In order to avoid additional components and assembly steps to constitute the anti-rotation device, the present invention proposes to use one end of the sleeve as the anti-rotation device.

A pump system includes a first pump and a second pump each having a plunger assembly. The plunger assembly includes a crosshead, a plunger, and a sleeve. The sleeve at least partially surrounds the plunger and an end of the crosshead. The sleeve is configured to create a fluid seal between the plunger and the crosshead.