JPS6026162Y2 - Light metal tube push rod for internal combustion engine valve train - Google Patents

Description

[Detailed description of the invention] The present invention relates to the improvement of a bushing rod used as a valve mechanism of an internal combustion engine, and in particular, an abutment end fitting is connected to a hollow end of a tube made of a light metal such as aluminum or aluminum alloy. The present invention relates to an improvement in the structure of a tube joint in a bush rod.

As shown in FIGS. 3 and 4, the conventional bushing rod has a shaft 12' connected to the back surface of the abutment end fitting 12, which is press-fitted into the hollow end 11' of the tube 11, and the hollow end of the tube 11
The ends of the end fittings 1 and 2 were connected to each other with their tips abutting against flat locking surfaces 14 in the radial direction provided at the base of the shaft of the end fitting.

For this reason, when the bushing rod is used for a long period of time and the reciprocating bushing movement is repeated, the abutting portion of the hollow end of the tube deforms into an outwardly expanding shape as shown by the imaginary line, which causes the intake and exhaust valves to open and close. This caused timing errors or deviations, which adversely affected the performance of the internal combustion engine.

Therefore, an object of the present invention is to overcome the above-mentioned drawbacks by promoting weight reduction of the bushing rod, and by easily connecting the end fitting of the bushing rod and the hollow end of the tubular body by means of a close-fitting pressure coupling means, and which also allows easy processing. To provide a strong bushing rod in which the hollow end of a tubular body does not expand and deform even after repeated reciprocating bushing movements for a long period of time just by rubbing.

Hereinafter, an example of the bush rod according to the present invention will be explained with reference to the drawings. In FIGS. 1 and 2, 1 is a tube made of a light metal material such as aluminum or aluminum alloy, and one of the tubes or As shown in FIGS. 1 and 2, at least the vicinity of the hollow end portion 1' of both has been previously subjected to hard alumite treatment 1'a.

2 is a contact end fitting for a bushing having a concave or convex curved head 3, and a locking surface 4 on the back surface of the head and a shaft body 2' that integrally projects rearward; The end fitting 2 is usually made of steel, and the curved head portion is hardened.

The bushing rod according to the present invention has the shaft body 2' of the end fitting 2 press-fitted into one or both hollow ends 1' of the tube body 1 whose hollow end part is hard alumite treated to lock the end fitting. The shaft body 2 is press-bonded to the inner circumferential wall surface of the hollow end portion of the tube body 1 in a tight fit state with the surface 4 and the end surface of the hollow end portion 1' of the tube body in contact with each other.

In this way, the bushing rod of the present invention has the locking surface 4 of the end fitting.
Since the hollow end 1' of the tube that comes into contact with the bushing has been hardened in advance by hardening alumite treatment, the hollow end will not expand outward and deform even if the reciprocating bushing movement is repeated over a long period of time. will disappear.

Therefore, it is possible to prevent a timing shift in opening and closing the intake and exhaust valves of the internal combustion engine caused by the deformation of the hollow end portion of the joint, so that there is no risk that the performance of the internal combustion engine will be impaired.

Well, according to the present invention, aluminum or aluminum alloy material can be used as the bush rod tube body without any problems, which makes it possible to further reduce the weight of the bush rod.Furthermore, resistance welding is not required when connecting the tube body and end fittings. There is an advantage that there is no need for any troublesome work such as the above, and the two members can be easily connected by simply press-fitting them tightly.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway sectional view of one end of a light metal tube bushing rod according to an embodiment of the present invention, FIG. 2 is a partially cutaway sectional view of one end of a light metal tube bushing rod according to another embodiment, and FIG. 4 and 4 are partially cutaway sectional views showing the structure and deformed state of a conventional bushing rod. 1... Aluminum or aluminum alloy tube body, 1'.
...Hollow end of tube, l'a...Hard anodized part, 2...Abutment end fitting for bushing, 2'...End fitting shaft Body, 4...Latching surface.

Claims (1)

[Scope of utility model registration request] A tube body 1 made of a light metal material such as aluminum or aluminum alloy, which has been subjected to hard alumite treatment 1'a in advance at least near the hollow end portion 1' of the tube body, and a concave or convex curved head, and the curved head A bushing rod for an internal combustion engine valve, comprising a locking surface 4 and a steel abutting end fitting 2 having a rearwardly protruding shaft body 2' coupled to the back surface of the hollow end portion 1' of the pipe body.
The shaft body 2' of the end fitting 2 is compressed, and the locking surface 4 of the end fitting 2 is sealed.
The shaft body 2' is press-bonded to the inner circumferential wall surface of the hollow end portion of the tube body 1 in a tight fit state with the hard alumite-treated end surface of the hollow end portion 1' of the tube body in contact with the end surface of the hollow end portion 1' of the tube body 1. A bushing rod made of light metal tube for internal combustion engine valves, characterized by: