JP2574584Y2 - Cam follower - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cam follower used for a valve train of an engine, and more particularly to a structure of a shaft pin for supporting a roller on an arm.

[0002]

2. Description of the Related Art As a cam follower used for a valve operating mechanism of an engine, there is a conventional one disclosed in Japanese Patent Application Laid-Open No. 62-7908. The structure is shown in FIG.

In FIG. 1, reference numeral 21 denotes an arm, and a fork 21a for holding a roller is formed at the tip of the arm 21. A hollow or solid support pin 22 is fixedly penetrated through the fork 21a.
A roller 24 is rotatably supported via a needle bearing 23.

[0004] Here, the outer peripheral surface of the central portion of the support pin 22 serving as the raceway surface of the needle bearing 23 is hardened by induction hardening, but both ends are left unhardened. Then, in a state where the support pin 22 penetrates the pin hole 25 of the bifurcated portion 21a, the uncured both ends are pin holes 2
It is fixed by caulking to the hole edge of No. 5.

[0005] In this cam follower, since the pivot pin 22 fits within the lateral width of the forked portion 21a, the shape of the arm tip becomes compact.

[0006]

In the above-described cam follower, if the amount of plastic deformation at both ends of the shaft pin 22 due to caulking is small, the plastically deformed portion due to caulking tends to drop. 22 may fall off.

To cope with this, it is only necessary to increase the caulking load applied to the spindle pin 22 to greatly plastically deform both ends. Particularly, in the case of a hollow spindle pin, the caulking load is large. Then, the load affects the center portion of the support pin 22, causing distortion of the raceway surface of the needle bearing 23, which hinders smooth rotation of the roller 24 and significantly increases wear.

The present invention has been made in view of the above-mentioned conventional problems, so that the spindle pin can be strongly caulked and fixed even with a small caulking load, and the spindle pin comes off and hardened at the center of the spindle pin. It is an object to prevent deformation.

[0009]

In order to achieve the above object, according to the present invention, a support pin is fixedly inserted through a fork at the end of an arm, and a roller is rolled on the support pin via a needle bearing. In the cam follower movably supported, the spindle pin has a needle bearing whose raceway surface is hardened, and a plastically deformable recess is formed on the outer circumference of both ends in an unhardened state. It was configured to be caulked and fixed to the edge of the pin hole of the fork.

[0010]

[Function] Since the outer periphery of both ends of the support pin is easily deformed due to the presence of the concave portion, the support pin is largely plastically deformed by a relatively small caulking load. Strongly fixed in pin holes.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the embodiments shown in FIGS. 1 and 2
1 is a sectional view of a cam follower, FIG. 2 is a side view of a pivot pin before mounting, (A) is a partially sectional side view, and (B) is an axial front view. is there.

As shown in FIG. 1, a cam follower according to this embodiment includes an arm 1 having a forked portion 1a for holding a roller at a tip thereof, and a hollow or solid member penetratingly fixed to the forked portion 1a. This is the same as the above-described conventional cam follower in that a spindle pin 2 is provided and a roller 4 rotatably supported on the spindle pin 2 via a needle bearing 3.

The feature of this embodiment resides in the support pin 2. The support pin 2 is previously subjected to a hardening treatment by a hardening method such as induction hardening on the outer peripheral surface of the central portion serving as the raceway surface of the needle bearing 3. As shown in FIG. 2, as shown in FIG. 2, a longitudinal groove-shaped concave portion 5 is formed on the outer periphery of both ends of the uncured portion other than the cured portion 2 a.
Are formed in large numbers. The portions including the recesses 5 are plastically deformed by a caulking load, so that both ends of the support pin 2 are fixed to the edge of the pin hole 6 of the forked portion 1a.

In the above configuration, since the outer periphery of both ends of the support pin 2 is easily deformed due to the presence of the concave portion, the outer periphery largely spreads with a relatively small caulking load. In this way, both ends are greatly plastically deformed,
The entire shaft pin 2 is strongly fixed to the pin hole 6 of the fork 1a, and does not fall off even after long-term use.

Further, since the caulking load applied to both ends of the pivot pin 2 can be relatively small, the caulking load does not affect the central hardened portion 2a and the hardened portion 2 due to the caulking load is not affected.
No deformation of a occurs.

In the above-described embodiment, the recesses 5 formed in the support pin 2 are formed in the form of longitudinal grooves and have a constant depth, but may have a shape as shown in FIG. In short, the concave portion 5 only needs to have a shape that promotes plastic deformation due to a caulking load on both ends of the support pin 2.

FIG. 3 shows a spindle pin according to another embodiment,
FIG. 1A is a partially sectional side view, and FIG. 1B is an axial front view thereof. That is, the concave portion 5 formed on the outer periphery of both ends of the support pin 2 may have a shape that expands in the circumferential direction, or may have a shape in which the depth of the recess increases toward the shaft end.

[0018]

As described above, according to the present invention, even when the caulking load is relatively small, the outer peripheries of both ends of the support pin are largely plastically deformed and strongly fixed to the edge of the pin hole. Therefore, not only can the pivot pin be prevented from falling off, but also there is no adverse effect on the hardened portion at the center of the spindle pin, and the hardened portion can be prevented from being deformed.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment of the cam follower of the present invention.

FIGS. 2A and 2B show a pivot pin of the embodiment, in which FIG. 2A is a partially sectional side view and FIG. 2B is an axial front view.

FIG. 3 shows a spindle pin according to another embodiment of the present invention;
Is a side view partially sectioned, and (B) is an axial front view.

FIG. 4 is a sectional view of a conventional cam follower.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Arm 1a Fork part 2 Support pin 2a Hardened part 3 Needle bearing 4 Roller 5 Concave part 6 Pin hole

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F01L 1/18 B21D 39/06 B21D 39/00 F16H 25/16 F16H 25/00

Claims (1)

(57) [Scope of request for utility model registration] 1. A cam follower in which a support pin is fixedly penetrated to a fork at the tip of an arm, and a roller is rotatably supported on the support pin via a needle bearing. The raceway surface is cured, and plastically deformable concave portions are formed on the outer periphery of both ends in an uncured state, and both ends are fixed by caulking to the edge of the pin hole of the forked portion. And a cam follower.