JPS603904B2 - Manufacturing method of brazed bolt with flange - Google Patents

Description

[Detailed description of the invention] The present application relates to a method of manufacturing a flanged brazed bolt.

Bolt with flange 1, as shown in Figure 1, collar 1, head 2
A bolt 3 is provided with a collar 4, and is used, for example, as a bolt for a liquid furnace 5 for an internal combustion engine shown in FIG. Therefore, the flanged bolt 10 is required not only to have bonding strength between the components, that is, the shaft portion 1, the head portion 2, and the collar portion 4, but also to have liquid tightness between them. Such flanged bolts are manufactured by an integral furnace brazing method instead of a welding method in consideration of mass production.

In that case, as shown in Fig. 1, the thread groove 6 is formed in the shaft part 1, the head part 2 and the collar part 4 are screwed into the groove, and the gap between the collar part 4 and the head part 2 is A possible method is to arrange the wax foil 7 and then integrate it in a furnace. In this manufacturing method, the head 2 and the collar 4 are integrally screwed onto the collar 1 before brazing, and the bonito wax foil 7 is held between the head 2 and the collar 4. Therefore, although it has the advantage of not requiring pressurized holding and odor detection before and during brazing, it also has the following drawbacks. That is, during brazing, the head 2 and the flange 4 are fixed to the shaft 1, so after the solder foil 7 melts and diffuses, the gap between the head 2 and the flange 4 is The gap M corresponding to the thickness remains formed. Such a gap M separates the head 2 and the collar 4 to reduce the joint area, and also prevents molten solder from spreading to the thread groove 6 and flowing outward depending on the posture during brazing. It will also happen. Therefore, in this manufacturing method, not only the bonding strength but also sufficient liquid tightness cannot be obtained because the thread grooves are not filled with solder. In view of the above, the present application provides a method for manufacturing a flanged brazed bolt that is easy to manufacture and provides sufficient joint strength and liquid tightness.

To explain based on an example, in FIG. 3, a bolt 20 that is a target of the manufacturing method of the present invention is composed of a collar portion 21, a collar portion 22, and a head portion 23.

The shaft portion 21 has thread grooves 24 and 25 on the outer periphery of both ends. The flange portion 22 is disk-shaped with a central entrance, and a threaded groove 26 is provided on the inner periphery of the entrance. The head 23 is in the shape of a polygonal column having a central opening with a threaded groove 27 on its inner periphery, and a recess 28 is formed on one side of the head to fit the central opening. The flanged brazing bolt 20 made of such components is manufactured as follows. First, insert the collar portion 22 into the threaded groove 25 at one end of the collar portion 21.
Screw together the central closing screw groove 26 of the
Insert the screw all the way to the end. Next, the thread groove 2 of the shaft portion 21 is also
5, the head 23 filled with the brazing material 29 is screwed into the recess 28, and the recess 28 on one side of the collar 22 and the head 23 is screwed into the recess 28.
Let's support with outsiders. As a result, the shaft portion 21 and the head portion 23
The flange portion 22 and the flange portion 22 are integrally assembled while retaining the brazing material 29. Further, the assembly thus assembled is placed in a furnace and heated to melt the waxy village 29. When taken out from the furnace, a brazed bolt 20 with an integrally fixed flange is obtained. As shown in FIG. 4, a brazed bolt with a flange can be formed using a bolt having a recess 28a for filling the brazing material in the flange 22a instead of the head 23a in the same manner.

In the above manufacturing process, the shaft portion 21, the collar portion 22, and the head portion 23 are each screwed into one piece, and the brazing material 29 is held therebetween without using a jig.

The held brazing material 29 is sealed in a recess 28 formed between the collar 21, the collar 22, and the head 23. The collar portion 22 and the head portion 23 abut against each other to increase the joint area. The brazing filler metal 29 filled in the recess 28 is heated and melted, and enters the minute gaps formed in the thread grooves 26, 25, 27 and the contact area between the collar 22 and the head 23 by capillary action. Seal the gap and secure them together. Bolt 2 assembled during furnace brazing
However, even if the position is disturbed, the solder metal 29 is sealed and the molten solder will not leak out to areas other than the joint surface. As described above, according to the manufacturing method of the present invention, since the head and the flange are brought into contact and brazed, it is possible to increase the joint area and obtain a bolt with high joint strength.

In addition, since the solder is heated while being sealed in the recess between the brim and the head, the molten solder will not leak out, regardless of the orientation of the assembly bolt during brazing. , diffuses into thread grooves, etc. to form bolts with high joint strength and liquid tightness. Furthermore, since the head, flange, and shaft are each screwed together and integrated, they can be brazed without the need for pressurization or odor control for retaining the brazing material, increasing manufacturing efficiency. .

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a brazed bolt with a flange made by the conventional manufacturing method, Fig. 2 is a sectional view of a furnace using a brazed bolt with a flange, and Figs. A sectional view of a brazed bolt with a flange obtained by the above method is shown. 21...Shaft part, 22...Brim part, 23...
... Head, 28 ... Recess, 29 ... Brazing material. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1 One end of a shaft part with threaded grooves on both ends has a central opening with a threaded groove on the inner periphery, and a collar part with a recessed part communicating with the opening on one side and a threaded groove on the inner periphery. a head with a central opening, or a collar with a central opening with a threaded groove on the inner periphery, a central opening with a threaded groove on the inner periphery, and a recess on one side communicating with the opening; The assembling process involves filling the concave part with brazing material and sequentially screwing the concave part into contact with the outside of the concave part on one side of either the collar part or the head part, and then putting the assembled part in a furnace. A method for manufacturing a brazed bolt with a flange, which comprises a fixing step of heating and melting a brazing material in a flange.