Claims:We Claim:

1. A roller tappet (10) for a high pressure fuel pump, said roller tappet (10) comprising:
a roller tappet body (12);
a roller (14) positioned within said roller tappet body (12);
a bearing bolt (16) positioned within said roller (14); characterized in that
a retainer ring (18) wound around said bearing bolt (16) and said roller tappet body (12) for securing said bearing bolt (16) to said roller tappet body (12), said retainer ring (18) orientated along a longitudinal axis of said bearing bolt (16) and perpendicular to a longitudinal axis of said roller tappet body (12).

2. The roller tappet (10) for the high pressure fuel pump in accordance with Claim 1, further comprising a groove (21) defined in said roller tappet body (12), wherein said retainer ring (18) is inserted onto the groove (21).
, Description:Field of the invention
[0001] This invention relates to a roller tappet and more particularly to a retainer ring that fastens a bearing bolt to a roller tappet body of the roller tappet.

Background of the invention
[0002] US 2006/288974 A describes a connection of a bearing bolt in a cylindrical housing of a roller tappet that is actuated in the direction of the longitudinal axis (Z), especially for a tappet push-rod valve drive of an internal combustion engine. The bearing bolt is supported in bore holes of the housing, which extend in a transverse plane (XY) to the roller tappet, perpendicular to the longitudinal axis (Z), and is connected with a positive and/or non-positive fit to the housing through material deformation. The material deformation is provided as one or more segments of which at least one segment completely encloses a radial load zone of the bearing bolt, and a section of the bearing bolt extending about the transverse plane (XY) is free from material deformation.

Brief description of the accompanying drawings
[0003] Figure 1 illustrates a schematic diagram of a roller tappet for a high pressure fuel pump; and
[0004] Figure 2 illustrates a side view of the roller tappet for the high pressure fuel pump.

Detailed description of the invention
[0005] Figure 1 illustrates a roller tappet 10 for a high pressure fuel pump. The roller tappet 10 comprises a roller tappet body 12 and a roller 14 positioned within the roller tappet body 12. A bearing bolt 16 is positioned within the roller 14. A retainer ring 18 is wound around the bearing bolt 16 and the roller tappet body 12 for securing the bearing bolt 16 to the roller tappet body 12. The retainer ring 18 is orientated along the longitudinal axis of the bearing bolt 16 and perpendicular to the longitudinal axis of the roller tappet body 12.

[0006] Figure 2 illustrates a side view of the roller tappet 10 for the high pressure fuel pump. The roller tappet 10 further comprises a groove 21 defined on the roller tappet body 12 such that the groove 21 goes around the entire roller tappet body 12 in a transverse plane perpendicular to the longitudinal axis of the roller tappet body 12.
[0007] In an exemplary embodiment, the retainer ring 18 is inserted onto the groove 21 that is defined on the roller tappet body 12 such that the retainer ring 18 extends circumferentially around the groove 21 of the roller tappet body 12 to form a tight fit within the groove 21 of the roller tappet body 12. In addition, the retainer ring 18 extends around the bearing bolt 16 to facilitate securing the bearing bolt 16 onto the roller tappet body 12. In the embodiment shown in Figure 1, the retainer ring 18 is orientated along the longitudinal axis of the bearing bolt 16 and perpendicular to the longitudinal axis of the roller tappet body 12.
[0008] The retainer ring 18 applies a restraining force on the bearing bolt 16 to facilitate securing the bearing bolt 16 to the roller tappet body 12. The restraining force applied prevents the bearing bolt 16 from disengaging from the roller tappet body 12. When it is required to disengage the bearing bolt 16 from the roller tappet body 12, the ends of the retaining ring 18 are pried apart, and the retaining ring 18 is withdrawn from the groove 21. Once the retaining ring 18 is withdrawn from the roller tappet body 12, the bearing bolt 16 may be disengaged from the roller tappet body 12.
[0009] It must be understood that the embodiments explained above are only illustrative and do not limit the scope of the disclosure. Many modifications in the embodiments with regard to leverage and dimensions of various components are envisaged and form a part of this invention. The scope of the invention is only limited by the scope of the claims.