JPS5815271Y2 - Single unit type cut wave patterned seat lug and seat pipe for bicycles - Google Patents

Description

[Detailed description of the invention] This invention is a single-unit type cut-out tube that is formed by integrally molding a seat lug and a seat pipe (also called a vertical pipe) that connect to the seat post directly below the bicycle saddle. This relates to a sheet/rug/sheet/pipe with a wave pattern.

In the conventional bicycle frame structure, the seat boss +C (not shown) located directly under the saddle is inserted into the seat pipe 3 through a common seat lug 1 as shown in FIG. However, the opening 1b of the seat lug 1 is engaged with the upper pipe of the tubular frame structure, and the handlebar of the bicycle is located in front of this upper pipe.

As shown in Fig. 1, the seat lug 1 is provided with a seat pin tightening part 2 on the opposite side of the opening 1b, and the seat post directly under the saddle is connected to the seat pipe through the upper opening 1b. The height of the saddle, which is inserted into the bicycle seat 3 and directly connected to the seat post, can be adjusted appropriately depending on the height of the bicycle rider, and this adjustment is made by tightening the pin mentioned above. A pin is passed through the opening that passes through the pin tightening part 2, and the seat pipe 3 is tightened by this pin.
to secure the seat post at the desired height.

Conventionally, the seat lug 1 shown in FIG. 1 is produced as a single component from a steel plate by processing such as pressing, and the method generally adopted is to fix the thus produced seat lug 1 to a seat pipe 3. .

The present invention provides a seat lug and seat pipe that is formed by integrally molding a seat lug and a seat pipe, which were conventionally produced separately.

The present invention will be explained below with reference to the drawings.

As mentioned above, the present invention involves manufacturing a seat/lug/sheet/pipe as an integrally molded product by using a pipe material as a starting material, setting this pipe material in a split mold, and applying the hydraulic bulge forming method. A bulging protrusion having an opening 4d shown in FIG. 1 must be molded.

The hydraulic bulge forming method is Japanese patent 417728゜41805
5.480529, 482147゜730010, etc., and it was introduced and implemented in the bicycle industry to which the present inventor belongs. One applied aspect of the hydraulic bulge forming method entitled ``and equipment'' was published in patent publication 12460/1989 (Japanese Patent No. 982106).
), and the present invention utilizes this.

According to the patent, a piece of pipe material is set in a split mold, high-pressure hydraulic oil is introduced from both ends of the pipe material, and a protrusion is formed on one side of the pipe shaft. - Next, take out the molded product from the mold, set this molded product in the second split mold, forcefully press fit a mandrel with a diameter slightly larger than the inner diameter of this molded product, and combine the pressing force of this mandrel with the second split mold. A desired pattern is produced on the outer surface of the molded product by using the cut wave pattern that is intaglio engraved.

Next, the hydraulic bulge forming method of the present invention will be described with reference to the drawings of the same patent.

FIG. 4 shows a hydraulic bulge forming press 20 with an arch-shaped frame, which is also used in the present invention.
This ram 22 fixes the upper mold 5 of the split mold, and the lower mold 5a thereof is fixed to the bed 6 of the press 20.

On both sides of the ram 22 are rams 23 and 24 that move horizontally using hydraulic pressure.
The sealed split molds 5 and 5a with the pipe materials set therein are firmly fixed on the bed 6 by the rams 22, 23, and 24, and hydraulic oil having a hydraulic pressure of 950 to 1,200 kg/cnt is introduced into the inside of the pipe materials. Then perform the necessary bulge forming.

For this purpose, the hydraulic circuit shown in FIG. 5 is used, and this figure also follows the drawing of the above-mentioned patent.

However, the following points are different: 1. One bulging protrusion is formed at one location on the pipe material.

In FIG. 5, the pipe material 3 set in the split molds 5, 5a
Inside the oil supply pipe 17a, pressureless hydraulic oil 12 is supplied from the oil supply pump 17 through oil introduction holes 19, 19a passing through the centers of the pistons 14, 14a.

17b, and both ends of the tube 3 are connected to the piston 14.
14a, the pump 17 is connected to the high pressure pump 16.
The hydraulic pressure is increased through the high-pressure pipes 16 a and 16 b to a predetermined pressure value of 950 to 1200 ky/d, and the pressurizing force of the vertical movable ram 22, the pressurizing force of the pair of horizontal movable rams, and the internal hydraulic pressure are increased. Under the combined pressure of , hydraulic bulge forming is performed, and a single bulging protrusion 11 shown in FIG. 6 is produced on one side of the tube shaft indented in the split mold.

Next, the pipe material 3 with one bulging protrusion 11 molded thereon is placed in the split mold 5.
, 5a, and set in the second split mold 5b shown in FIG.

This second mold differs from the second mold shown in the above-mentioned patent in the following respects: 16 Only one mandrel is used.

2. Of the hydraulic circuits, the one on the right side of the diagram is unnecessary.

As mentioned above, since the cut wave pattern 4at4b (FIG. 3) is engraved on the second mold half 5b, it has the bulging protrusion shown in FIG. 6 set inside the second mold half. When a mandrel 18 having a diameter slightly larger than the inner diameter of the pipe material is strongly press-fitted into the pipe material using hydraulic driving force, a desired pattern is imparted to the outer surface of the pipe material according to the pattern engraved on the second mold. be done.

However, in this case, the pattern is not applied by high-pressure hydraulic oil introduced into the pipe, but by the pressing force of the mandrel, and the force for pushing the mandrel into the pipe is due to hydraulic pressure.

As shown in FIG. 3, the height difference between the thick portion 4a and the thin portion 4b is about 1 mm or less.

Next, the raw tube material 4 with the cut wave pattern and the bulging protrusion 11 is taken out from the second split mold, and the upper end of the protrusion 11 is cut off to form an opening 4d.

The pin tightening part 7 shown in FIG. 8 is attached to the outer surface of the pipe material 4 which is formed as shown in FIG.
Weld and secure as shown in the figure.

This pin tightening part 7 is provided with a through hole.

Incidentally, the openings 1a and 1b of the seat lug 1 shown in FIG.
correspond to openings 4c and 4d in FIG.

Furthermore, the shape of the seat lug 1 shown in FIG. 1 with the ears 2 is different from the shape shown in FIG.
As can be clearly seen from the figure, the molded product shown in FIG. 9 is a final product after the slit 8 is cut out.

Needless to say, the function of the seat lug is to insert a pin through both ears of the pin tightening part, tighten this pin against the seat post inserted into the seat pipe from the opening 4c, and tighten the seat lug. The post is secured in place within the seat pipe.

That is, after welding the part 7 shown in FIG. 8, two ears 2 are formed by the slits 8.

As described above, according to the present invention, the seat lug and the seat pipe are integrally molded, which simplifies the manufacturing process. , it is not inferior to conventional products in terms of strength,
Its practical effect is a dog.

[Brief explanation of the drawing]

Figure 1 is a sketch of an example of a conventional seat lug, Figure 2 is a perspective view of a seat pipe, and Figure 3 is a sheet pipe with a cut wave pattern and a bulging protrusion with an opening. Fig. 4 is a schematic diagram of a hydraulic bulge forming machine; Fig. 5 is a cross-sectional view of the process of setting a sheet pipe in a split mold and forming a bulging protrusion by the hydraulic bulge forming method; Fig. 6 The figure is a perspective view of a product in which a bulging protrusion is molded into a sheet pipe by the process shown in Figure 5, and Figure 7 shows the molded product shown in Figure 6 set in a second split mold to give it a cut wave pattern. A sectional view of the process, Figure 8 shows the pin tightening part, Figure 9 shows the pin tightening part in Figure 8 welded to the sheet pipe, and the first
Figure 0 is a rear view of the completed seat/lug/seat/pipe. 1... Seat lug, 2... Ear as above, 3... Sheet pipe, 4... Unfinished molded product, 5゜5a... ...First split type, 20...
...Hydraulic bulge forming machine, 11...Bulging protrusion, 14-17...Hydraulic circuit and parts, 18.
...Mandrel, 5b...Second split mold, 6
...Bed, 12...Hydraulic oil, 7...
...Pin tightening parts, 8...Slit, 9.
...Final product.

Claims (1)

[Scope of utility model registration request] An opening 4c is provided at the upper end of the sheet pipe 3, and the sheet is inserted into the thick cut wave pattern area 4a of the sheet pipe 3.
A bulging protrusion having an opening 4d formed integrally with the pipe 3 is provided, and a sheet is attached to the outer wall surface of the sheet pipe at a symmetrical position with respect to the sheet pipe axis of the bulging protrusion of the sheet pipe 3. The pin fastening part 2 is fixed by welding, and the sheet/pin fastening part 2 is fixed to the outer wall surface including the seat/pin fastening part 2.
A single unit type cut wave patterned seat lug/seat pipe for bicycles characterized by having a slit of a predetermined length in the same direction as the pipe axis.