JPH0610098Y2 - Valve lifter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a valve lifter installed in a valve train of an engine and driven by a cam to open and close an engine valve.

[Conventional technology]

A valve lifter, which is one of the engine valve system components, is located between a cam and a push rod or between a cam and a valve, and moves up and down by driving the cam to open and close an engine valve. A disk-shaped adjusting shim is fitted to a portion of the top surface which comes into contact with the cam. And this adjusting sim
Since it is always used in contact with the cam, it is worn out so much that it needs to be replaced occasionally. Various means have been proposed in the past for the replacement of the adjusting shim.

As an example, as shown in FIG. 3, the valve lifter 1
There is a valve lifter provided with an outer edge portion 3 for forming a recess 2 into which an adjusting shim is fitted, and notches 4, 4 provided on the diametrically opposite sides of the outer edge portion 3 (actually developed sho 58 -67906).

Further, as shown in FIG. 4, an annular narrow groove 5 is provided on the inner wall 8 of the outer edge portion 3, while the adjusting shim 6 has an inner wall on the inner diameter side of the narrow groove 5 at a part of its outer peripheral portion. There is also one in which a notch 7 reaching near is formed (see Japanese Utility Model Laid-Open No. 60-69303).

[Problems to be solved by the invention]

In the valve lifter of the type shown in FIG. 3, since the outer edge portion 3 has the notches 4 and 4, the strength is reduced. In particular, when the weight is made of a lightweight member such as aluminum, the strength is insufficient. Because of this, the outer edge portion 3 may be damaged, and its function cannot be fulfilled.

Further, in the case of the type shown in FIG. 4, although the strength is not so lowered as in the case of the type shown in FIG. 3, the strength is lowered because the annular groove 5 is formed over the entire circumference of the outer edge portion 3. The tendency is unavoidable, and the adjusting sim 6
Also, since the notch 7 is required, there is also a problem that the machining cost increases together with the formation of the peripheral groove 5 on the outer edge of the valve lifter.

SUMMARY OF THE INVENTION In view of the above points, the present invention intends to provide a valve lifter that can prevent the strength of the valve lifter from being lowered as much as possible and that can easily perform an adjusting shim replacement operation.

[Means for solving problems]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a valve lifter in which an outer edge portion for forming a recess into which an adjusting shim is fitted is provided on a top surface portion to be brought into contact with a cam. , A part of the inner wall in contact with the outer peripheral surface of the adjusting shim is provided with a narrow groove having a semicircular cross section reaching from the top to the top surface of the valve lifter, and the outer edge is entirely formed in all parts in the height direction. There is provided a valve lifter which is provided so as to be continuous to the circumference, and further has a hemispherical small recess provided on the top surface portion of the valve lifter which is continuous with the narrow groove.

[Action]

In the valve lifter of the present invention having the above-described structure, in order to remove the adjusting shim fitted on the top of the valve lifter, a gap formed between the valve lifter and the adjusting shim and having a small groove and a small recess is formed. The adjusting shim can be easily removed by inserting a thin rod having a hook-like tip into the and inserting the tip of the rod into the lower surface of the adjusting shim.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 showing an embodiment of the present invention, a cylindrical valve lifter 1 is provided with an outer edge portion 3 in an annular shape so as to form a recess 2 at the top thereof. The recess 2 is for fitting an adjusting shim (not shown). A fine groove 11 having a semicircular cross section that extends from the top portion 9 to the top surface portion 10 of the valve lifter 1 is provided at one location on the inner wall 8 of the outer edge portion 3 that contacts the outer peripheral surface of the adjusting shim. Even if the narrow groove 11 is provided in the outer edge portion 3, all the portions in the height direction thereof are still continuous over the entire circumference. That is, the outer edge portion 3 has no notch. Further, the valve lifter 1 has a top surface portion 10 provided with a hemispherical small recess 12 continuous with the lower end of the narrow groove 11 (FIG. 2).

When using the valve lifter 1 configured as described above, an adjusting shim (not shown) is fitted into the recess 2 on the top surface, and a cam (not shown) is inserted into the adjusting shim.
Are mounted in the valve train so that they contact each other.

When it was necessary to replace the adjusting shim, the tip was hooked in the gap between the valve lifter 1 and the adjusting shim, which was formed by the narrow groove 11 having a semicircular cross section in the outer edge portion 3. After inserting a thin rod (not shown) so that its tip reaches the small recess 12 formed in the top surface portion 10, the hook-shaped tip portion of this rod is hooked on the lower surface of the adjusting shim to adjust it. The sting sim is raised and it is removed.

By using the narrow groove 11 provided in the outer edge portion 3 and the small recess 12 provided in the top surface portion 10 in this manner, the adjusting shim can be easily removed with a single thin rod and replaced with a new one. .

Moreover, since this rod is inserted, only the thin groove 11 is provided in the outer edge portion 3 at one position thereof, and it is not necessary to form the notch, so that the reduction of the strength of the outer edge portion 3 is avoided. Further, the valve lifter 1 has a thin groove 1 on the inner wall of the outer edge portion 3.
1 has a structure in which the small recess 12 is formed in the top surface portion 10, so that it can be easily formed by forging or the like, and the cost can be reduced.

[Effect of device]

Since the present invention has the above-mentioned configuration, the notch is not required in the outer edge portion of the valve lifter top portion, the strength of the outer edge portion is secured, and the adjusting shim can be replaced.

In other words, the thrust force acting on the shim is not concentrated and deforms or is damaged in the notch as in the case where the notch is provided in the outer edge, and even if there is a part where the wall thickness is thin, the outer edge does not exist. Since stress is distributed all around the circumference, stress is distributed in the circumferential direction to avoid concentration of stress, and the strength of the entire outer edge is reduced like an annular narrow groove formed over the entire inner circumference of the outer edge. And the strength of the outer edge is secured.

In addition, since the outer edge does not require a cutting process for forming a notch, the valve lifter can be easily formed by forging, etc. Furthermore, a groove is provided all around the outer edge, or the adjusting shim itself is not cut. Since no special processing such as providing a notch is required, the manufacturing cost can be reduced.

[Brief description of drawings]

FIG. 1 is a plan view of an embodiment of the present invention, FIG. 2 is a vertical sectional front view of the same as above, FIG. 3 is a perspective view of a conventional valve lifter, and FIG. 4 is a plan view of another type of conventional valve lifter. 1 ... Valve lifter, 2 ... Recess, 3 ... Outer edge, 4 ... Notch, 5 ... Fine groove, 7 ... Notch, 8 ... Outer edge inner side wall, 9 ... Outer edge top, 10 ... Valve lifter top surface, 11 ... Fine groove, 12 ... Small recess.

Claims (1)

[Scope of utility model registration request] 1. A valve lifter in which an outer edge portion for forming a recess into which an adjusting shim is fitted is provided on a top surface portion to be brought into contact with a cam, wherein an outer periphery of the adjusting shim of the outer edge portion. A small groove having a semicircular cross section reaching from the top to the top surface of the valve lifter is formed on a part of the inner wall in contact with the surface so that the outer edge is continuous over the entire circumference in all parts in the height direction. A valve lifter, characterized in that a hemispherical small recess is also provided on the top surface of the valve lifter connected to the narrow groove.