JPH0363447B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for manufacturing clawed steel sleepers used for railways, crane tracks, etc.

[Conventional technology] In recent years, steel sleepers have come to be used due to the increase in the price of wooden sleepers due to the depletion of wood resources and the difficulty of disposing of concrete sleepers.
Various forms have been developed and put into practical use as disclosed in Japanese Patent Application Laid-open No. 135403 and Japanese Patent Application Laid-Open No. 56-85001. Recently, a channel steel 1 as shown in the front view and side view of FIGS. 8a and b was press-worked, and downwardly bent pawls 2a and 2b were formed at both ends as shown in the plan view and side view of FIGS. 9a and b. The clawed steel sleeper 3 having a slightly curved shape in the length direction has a high practical effect and has come to be used in large quantities.

Next, a well-known manufacturing method for the clawed steel sleeper 3 will be explained with reference to FIGS. 10 to 12. 10th
11 are explanatory diagrams showing the state in the process of forming a claw part by bending, and are driven by a pedestal 5a fixed to a pedestal 4 and a pressing cylinder (not shown) and a pressing metal fitting 5b. Then, the groove steel 1 is held in a downward position, and then the end of the groove steel 1 is press-bent using a bending die 6 fixed to the base 4 and a pressing cylinder (not shown) to form the claw portion 2a. Next, the channel steel 1 is left and right reversed, and the other end is press-bent in the same manner as shown in FIG. 11 to form claw portions 2a and 2b at both ends. Then the 12th
As shown in the figure, support fittings 9a and 9 are attached to both ends of the pedestal 8.
b is fixed, a mold bending die 10 is provided in the center,
The claws 2a, 2b of the channel steel 1 are supported by the metal fittings 9a, 9b.
A mold bending punch 11 is mounted on the mold and then driven from above by a pressing cylinder (not shown)
In addition to such cold or warm pressing methods, hot bending methods and forging methods are also available. It has been adopted.

[Problems to be Solved by the Invention] Now, Fig. 7 is a perspective view of the claw part of the clawed steel sleeper, which has a complicated waveform because it is formed by bending channel steel. Due to unevenness in the material, slight differences or changes such as distortion in the shape of the bending punch or die, or lubrication, as well as misalignment of the machining point or machining speed, the shape may be uniform and the shape must be the same. There is a problem that it is extremely difficult to achieve dimensional accuracy of
The manufacturing method shown in Fig. 2 is a means of fixing the channel steel 1 using a pedestal 5a and a press fitting 5b and strongly pressing and bending it.The material is easily damaged, and since one side is pressed at a time, the dimensions and shape of both sides are fixed. It is difficult to make the dimensional accuracy equal, and many corrections and re-pressing are required to obtain the desired dimensional accuracy.Furthermore, despite such correction work, the tolerance for dimensional accuracy is tight, resulting in a high rate of rejection and rework. In addition to the pressing process, there are many operations such as reversing and transporting, which increases labor costs.Also, the hot bending and forging methods mentioned above have high energy costs and are prone to quality defects. There is also the problem that it is difficult to increase dimensional accuracy.

The object of the present invention is to provide an economical manufacturing method that has excellent productivity, great labor-saving effects, good dimensional accuracy, and extremely few defects.

[Means for Solving the Problems] In order to achieve the above-mentioned object, the inventors of the present invention placed a grooved steel in a supine position on a lower die hardware having a bending die in the center and bending dies at both ends. Then, the grooved steel is pressed using an upper die punch hardware having a die bending punch in the center and bending punches at both ends, and press bending is carried out in one step. He succeeded in solving all the problems by developing a manufacturing method for sleepers.

[Function] In the method of the present invention, the groove steel is placed in a supine position on the lower die hardware having a bending die in the center and bending dies at both ends, so the stability of the posture of the groove steel is good. There is extremely little need for special tools or operations to maintain the position, and there is no fear of the press shifting or jumping up during press work.

Since both ends of the grooved steel are pressed simultaneously using an upper punch metal piece that has a bending punch in the center and bending punches at both ends, the deviations and distortions that tend to occur during mold bending are avoided. It is possible to perform smooth mold bending without any problems.

Furthermore, when a rolling die equipped with a roller having a tire-shaped bulge is used as a bending die, the die rolls following the workpiece during bending.
Since a desired recess can be formed in the claw part and the workpiece can be guided, unnecessary expansion of the claw part in the width direction can be suppressed and the claw part can be formed with a desired shape.

In addition, since the die rolls, there is no scratching or scratching on the surface of the workpiece.
Due to its dual nature of processing action and guiding action, a product with excellent shape and no scratches can be obtained.

Furthermore, when a round-head cylindrical roller is used as a bending punch, the groove-shaped steel is pushed open from the inside to the outside and the bending action is performed along the arcuate circumferential surface.
An unreasonable bending force that would cause a breakage is not applied to the channel steel 1 during bending.

[Example] Now, the present inventors have developed the upper die punch hardware 14 shown in the front and side views of FIGS.
Lower die hardware 1 shown in the front and side views of b
7 was used to successfully obtain an accurate shape by one-step press bending.

Upper punch hardware 1 as shown in Figure 4 a and b
A mold bending punch 12 with a slightly downwardly curved presser surface 12a is provided at the lower central part of 4, and round-headed cylindrical roller-shaped bending punches 13a are provided at both ends around the mold bending punch 12. 13b is fixed.

On the other hand, as shown in the front and side views of FIG. In the section, rolling roller type bending dies 16a, 16b are attached to the pivot metal fitting 1.
It is rotatably supported by the shafts 8a and 18b.

Therefore, as mentioned above, the lower die hardware 1
When the channel steel is placed in a supine position on 7 and pressed with the upper punch hardware 14, it becomes possible to manufacture a desired clawed steel sleeper with just one press. Such a processing method was previously unknown and was thought to be impossible due to the complicated shape of the claw as described above, but the inventors and others have conducted numerous experimental studies. This was the first time that it was successfully developed.

Next, the specific method of the present invention will be explained in more detail with reference to the drawings according to the processing procedure.

Figure 1 shows the bending die 1 of the lower die hardware 17.
6a, 16b, the groove steel 1 is placed in a supine position, and the bending punches 13a,
13b is an explanatory diagram showing a step immediately before pressing is started by bringing the groove steel 1 into contact with the groove steel 1, and only the groove steel 1 is shown in a longitudinal cross-sectional view for convenience of explanation.

In order to prevent the workpiece, that is, the channel steel 1, from shifting from a predetermined position in such press working, and to ensure safety during the process, guide hardware (not shown) can be appropriately installed to make the work more efficient. I can do things.

Although the upper punch metal fitting 14 is not shown, it is engaged with an upper pressing cylinder of the press machine and is operated to move up and down.

Next, as shown in FIG. 2, when the upper punch hardware 14 is pushed down, both ends of the channel steel 1 become flat and open outward and are bent from the portions that contact the bending punches 13a and 13b.

Furthermore, as shown in FIG.
Press down and bend the back side of the channel steel 1 (which becomes the rail mounting surface when formed as a sleeper) with the mold bending die 1.
On the other hand, the bending punches 13a, 13b and the bending dies 16a, 16b continue to bend the ends with the bending punch 12 until they come into contact with the bending punch 12 and the bending die 15. When the mold bending is completed, the bending of both ends is also completed at the same time. In this way,
A claw steel sleeper is completed in one press step.

Next, dimensions of an example of a press apparatus used for carrying out the present invention will be shown.

To manufacture a clawed steel sleeper with a total length of approximately 2790 mm, a total height of 200 mm, and a bottom opening width of 280 mm, the following upper punch hardware and lower die hardware were used.

Upper punch hardware Bending punch spacing 2360mm Bending punch width 910mm Lower die hardware Bending die spacing 2850mm Bending die width 910mm Figure 6 shows a perspective view of the end bending process.

Components with the same symbols as in FIGS. 1 to 3 and FIGS. 4 to 5 described above are the same members, so explanations will be omitted. In FIG. 6, the bending punch 13a has a rounded end. The body is a roller type with a cylindrical shape, and a support arm 14a is attached to the upper punch hardware 14.
It is fixed by welding through.

The dimensions of the bending punch 13a are the same as those of the channel steel 1.
When the dimensions are set so that the groove steel 1 can be opened outward from the inside one after another, the ends of the channel steel 1 are easily expanded and bent into a flat shape by a press, resulting in a claw with excellent dimensional accuracy and quality. Part formation is possible.

In addition, the bending die 16a, that is, the rolling die, is provided with a tire-shaped expansion part 19 in the center of the roller, which is the main part thereof, to actively form a dent in the claw part during bending, and at the same time, to prevent bending. As described above, when the guiding action is performed, unnecessary expansion of the claw portion in the width direction is prevented and the claw portion can be formed in a desired shape.

[Effects of the Invention] The manufacturing method of the present invention can manufacture the desired clawed steel sleepers in one press step, so it is extremely productive and economical, and there are no problems with dimensional accuracy or quality. Since there is no correction or re-pressing after pressing, it has the effect of significantly reducing sleeper manufacturing costs.

[Brief explanation of drawings]

1 to 3 are explanatory diagrams showing the press bending process of one embodiment of the present invention, and FIG. 1 shows the start of pressing,
Fig. 2 shows the press in progress, Fig. 3 shows the press completed, Figs. 4 a and b are front and side views of the upper punch metal piece according to the present invention, and Figs. 5 a and b show the lower die metal piece. 6 is a schematic perspective view showing the bending press working of the claw portion, and FIG. 7 is a front view and a side view.
The figure is a schematic perspective view of the claw part of a clawed steel sleeper, Figure 8a,
b is a front view and side view of the channel steel, Fig. 9 a, b
1 is a plan view and a side view of a clawed steel sleeper, and FIGS. 10 to 12 are explanatory diagrams of a conventional press bending process. 1... Channel steel, 2a, 2b... claw portion, 3... clawed steel sleeper, 4... pedestal, 5a... pedestal, 5b...
...Press fitting, 6...Bending die, 7...Bending punch, 8...Plinth, 9a, 9b...Supporting metal fittings,
10...Bending die, 11...Bending punch,
12...Mold bending punch, 12a...Press surface, 13
a, 13b...Bending punch, 14...Upper punch hardware, 15...Bending die, 16a, 16b
...Bending die, 17...Lower die hardware, 1
8a, 18b... Pivot support hardware, 19... Expansion part.

Claims (1)

[Claims] 1. A grooved steel is placed in a supine position on a lower die hardware having a bending die in the center and bending dies at both ends, and then a bending punch is placed in the center and a bending punch is placed at both ends. A method for manufacturing a sleeper made of clawed steel, characterized in that the grooved steel is pressed using an upper punch hardware equipped with a bending punch and press-bent in one step. 2. The method for producing a clawed steel sleeper according to claim 1, wherein a rolling die equipped with a roller having a tire-shaped bulge is used as the bending die. 3. The method for manufacturing a clawed steel sleeper according to claim 1, characterized in that a round-headed cylindrical roller is used as the bending punch. 4. The method for manufacturing a claw steel sleeper according to claim 1, characterized in that a trapezoidal die is used as the shape bending die.