JPS5940598Y2 - chain - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a type of chain using a wound bush.

More specifically, when obtaining a rolled bushing by winding and forming a flat plate material into a cylindrical shape, the diameter of both ends of the bushing is made larger than the center part, and the press-fit type is used when the bushing is press-fitted and fixed to the inner link plate. The present invention relates to a chain that is designed to have a straight shape with equal diameters continuous in the length direction, to prevent local wear of bushes and pins, and to improve lifespan and durability.

FIG. 8 shows a cross-sectional view of a main part of the chain 1, in which a pair of left and right outer link plates 2, 2 are connected and integrated by a pin 3, and inner link plates 4, 4 are connected and integrated by a bush 5.

A mounting hole 4a is formed through each inner link plate 4.
A is press-fitted, and the bushing 5 and the inner link plate 4 are press-fitted and fixed.

In this case, a press-fitting load acts on the end portion 5a of the bushing 5 from the outer diameter direction to the inner diameter direction, and as a result, a convex portion 5b protruding in the inner diameter direction is formed on the bushing 5 at the inner link plate 4 portion by the press-fitting mold. The inner diameter of the bushing 5 is locally narrowed.

When chain 1 gets caught in the sprocket and rotates,
The chain 1 will perform a bending movement, but this bending movement is influenced by the relative rotational movement between the pin 3 and the bush 5.

As described above, when the convex portion 5b protrudes from the inner diameter hole of the bush 5, the bush 5 comes into sliding contact with the pin 3 only at this convex portion 5b, causing local wear on the pin 3 and the bush 5, which causes the chain to deteriorate. This causes elongation, reducing the lifespan and durability of the chain.

The inventor of the present invention has devised the present invention in view of the above-mentioned problems in the past, in order to effectively solve the problems.
In particular, the present invention has been developed to effectively solve the above problems while retaining the advantages of a rolled bushing, which is more cost-effective than a bushing made by drawing.

The object of the present invention is to provide a chain in which a rolled bushing is formed by winding a flat plate material into a cylindrical shape. As a result, when the bushing is press-fitted and fixed to the inner link plate, the diameter of the bushing is made uniform and continuous in the length direction by the press-fitting type, which equalizes the sliding contact between the pin and the bushing, preventing local wear and unevenness. To provide a chain designed to prevent wear and improve lifespan and durability.

A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a half-cut view of a winding bushing, and FIGS. 2 to 6 are diagrams showing the manufacturing of the winding bushing according to the processing order.

The entire winding bush 10 is formed into a drum shape, and both ends 10
a, 10a has an outwardly widening tapered portion 11
11, and the diameter of the end portion 10a gradually increases outward.

The diameter of the central portion 10b that connects both end portions 10alOa is made equal and continuous in the length direction and smaller in diameter than the tapered end portion 10a, thereby making the winding bushing 10 bilaterally symmetrical and making the diameter of both end portions 10a, 10a Center diameter 1
The diameter should be larger than 0b.

This rolled bushing 10 is a flat plate material W of equal thickness shown in FIG.
A first intermediate workpiece W1 is obtained by forming and processing both ends wta and Wla downward at an appropriate angle, and the other end parts W11 . W1b is rolled and curved inward using a roll means or the like.

As a result, it is formed as shown in FIG.

Both curved ends W1b, W1b of the first intermediate workpiece W1 are further wound and curved to obtain a second intermediate workpiece W2 as shown in Fig. 5, and the open edges W2b, W2b are tightly combined to form a finished product. Get W3.

The wound bushing 10 is formed by the above steps, and both ends 10 a
, 10b has a larger diameter than the central portion 10b,
Moreover, it is formed in a tapered shape that widens outward.

The spring bushing 10 described above can be processed and formed using the same method as a conventional rolled bushing formed into a cylindrical shape, and when forming an intermediate workpiece, both ends W, a, and W1a are curved as shown in FIG. The only difference is that it is bent in the opposite direction to the winding direction.

Therefore, the winding bushing 10 can be manufactured while maintaining its relatively simple manufacturing and cost advantages.

When the winding bushing 10 is press-fitted into the mounting hole 4a of the inner link plate 4 described above, both ends 10a with larger diameters,
Since the press-fitting load acts on 10a, this part 10a
is pressed in the inner radial direction and its diameter decreases, and at the end of the press-fitting, it becomes the same or approximately the same as the diameter of the central portion 10b, and has a straight shape in which the approximately equal diameter continues in the length direction.

Therefore, during bending motion of the chain, the winding bush 10 and the pin 3, which rotate relative to each other, do not come into sliding contact partially, but are in sliding contact evenly over the entire surface, preventing local wear and chain elongation caused by this. can do.

FIG. 7 shows a modified embodiment of a winding bushing. This winding bushing 10-1 has a flat part 13.13 continuous to the end of a widening tapered part 12.12. The diameter of both end portions 10-1a, 10-1a provided with 13 becomes larger than that of the central portion 1O-1b depending on the amount of expansion of the tapered portion 12.

According to this embodiment, the flat portion 13 allows the bushing 10-
1 can be easily press-fitted into the mounting holes 4a of the inner link plates 1 and 4, and the ease of assembling the chain can be improved. Since it is made larger than the center part, the diameter of both ends becomes approximately the same as the center part by press-fitting into the inner link play 1, and the diameter of both ends becomes approximately the same as that of the center part. It is possible to effectively prevent local wear of the pins and bushings by making even sliding contact without sliding on the chain, contributing to improving the durability and life of the chain.

Moreover, according to the present invention, since it can be manufactured by the same molding process as conventional rolled bushings, it is possible to maintain the cost advantage over bushings made by drawing process, and the above-mentioned It can be mass-produced at low cost while still being effective, and has a remarkable feature in practical use.

[Brief explanation of the drawing]

FIG. 1 is a half-cut view of the winding bushing, FIGS. 2 to 6 are diagrams showing the forming of the winding bushing according to the processing order, and FIG. 7 is a diagram similar to FIG. 1 showing a modified embodiment of the winding bushing. FIG. 8 is a sectional view of the main part of the chain. In the drawing, 1 is a chain, 4 is an inner link plate, and 10 is a chain.
10a is the end portion, and 10b is the center portion.

Claims (1)

[Scope of utility model registration request] In a chain formed by winding and forming a flat plate material into a cylindrical shape to form a wound bushing, and press-fitting both ends of the wound bushing into the mounting hole of an inner link plate, the winding bushing is inserted into the mounting hole of the inner link plate. At the time of press-fitting, the portion of the winding bushing that is press-fitted and fitted into the mounting hole is formed in advance into a diameter-expanding tapered shape so that substantially equal diameters are continuous in the length direction. chain.