JPH04210868A - Manufacture of fitting metal tool - Google Patents

Abstract

PURPOSE:To obtain a coupling metal tool surely formed with braze-padding near the joining part by arranging wall face formed with a hole in a fixed part and plural cut-out parts at one side of outer peripheral face in a pipe part and joining with the brazing. CONSTITUTION:The through hole 20A and the pipe part 14 are joined with copper brazing. On the outer peripheral face of the pipe part 14, the copper brazing filler prepared by cutting a linear copper brazing filler and bending as ring-state, is set and heated together with the fitting metal tool. By this method, molten copper brazing filler is surely penetrated into gap between the through hole 20A and the pipe part 14, and by forming eutectic structure on inner face of through hole 20A in the fixed part 12 and outer peripheral face in the pipe part 14 with the copper brazing filler, the sticking force is worked, and the fixed part 12 and the pipe part 14 are joined.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing a fitting, and is particularly used for hydraulic piping for brakes on steering wheels of vehicles, etc., in which a socket to which a flexible hose is connected is connected to a fixed part. The present invention relates to a method of manufacturing a joint fitting that is inserted into a hole formed on the outer peripheral surface of a metal fitting and brazed thereon.

[Conventional technology]

There are various methods for joining metals, one of which is brazing.

Joining metals by brazing does not melt the metals to be joined and does not apply an extremely large force to the metals, so it can be joined without impairing the original properties of the metals.

This brazing includes copper brazing using copper solder.

- Copper wax melted in boat fishing has the property of increasing its viscosity as the temperature drops, gathering in areas with high viscosity due to surface tension, and also having the property of entering narrow gaps by capillary action. When this molten copper solder adheres to the metal surface, a eutectic structure is formed on the metal surface, which has the property of exerting adhesive force on the metal surface. Copper brazing utilizes the properties of copper solder to join metals together.

This copper brazing is sometimes used to manufacture fittings used to connect flexible hoses. For example, it is used to manufacture a joint fitting 70 used for a connection part of a hydraulic piping for a vehicle brake shown in FIG. 5. This fitting 70 includes a socket 16 having a fixing part 12 and a pipe part 14.
Copper brazing is used to join the fixing part 12 and the tube part 14 of the socket 16.

A through hole 2O is provided on the outer peripheral surface of the fixing part 12 of this joint fitting 70.
A is drilled, and a socket 16 is inserted into this through hole 2OA.
The tip of the tube portion 14 is press-fitted and tightly joined by copper brazing. Further, between the vicinity of the outer periphery of the through hole 2OA and the outer circumferential surface of the tube portion 14, build-up is performed using copper brazing to improve fatigue strength.

[Problem to be solved by the invention]

When joining by copper brazing, if the gap between the overlapped metal parts is too wide or too narrow, a joining failure will occur.
The gap between the surface of the metal to be inserted and the inner surface of the hole is 0. Om
m to 0.05 mm is considered ideal.

In other words, if the gap at the connection part is wide, or if extremely high pressure is applied to a part of the joint surface due to press fitting (if it is too narrow), the copper solder will completely penetrate into the gap at the joint part. No copper solder has entered the joint [l
Since iJ remains, a bonding failure will occur.

Since the joint between the fixed part of the fitting and the pipe part must be filled with copper solder, the pipe part must be tightly press-fitted into the hole in the fixed part to prevent the copper solder from flowing out. For this reason, the copper solder does not flow sufficiently into the gap between the inner surface of the hole in the fixing portion and the outer circumferential surface of the tube portion, resulting in poor bonding.

In order to prevent defects in the copper brazing of the fitting, the machining accuracy between the hole in the fixing part of the fitting and the outer circumferential surface of the socket must be high, which requires skilled technology and increases production costs. I end up.

In consideration of the above-mentioned facts, the present invention aims to provide a method for manufacturing a joint fitting in which a fixing part and a socket are reliably joined by brazing through simple processing.

[Means to solve the problem]

A method for manufacturing a joint fitting according to the present invention is a method for manufacturing a joint fitting in which a cylindrical tube portion is inserted into a hole drilled in the outer circumferential surface of a fixed portion and joined by brazing, the method comprising: A plurality of notches are provided in at least one of the wall surface forming the fixing part and the outer peripheral surface of the tube part, and the tube part is inserted into the hole of the fixing part and joined by brazing.

[Effect]

According to the present invention having the above configuration, the notch is formed either in the hole drilled in the outer circumferential surface of the fixing part or in the outer circumferential surface of the tube section inserted into the hole.

By forming this notch, the tube part can be press-fitted into the hole of the fixing part, and in places where the fit is tight,
The fixed part or the pipe part is plastically deformed, and the excess material can be brought to the vicinity of this notch.

This allows for areas where the fit is extremely tight, i.e.
Since the gap between the hole and the tube can be eliminated from the part where it becomes extremely narrow, it is possible to reliably infiltrate the melted wax into the gap between the hole and the tube. This penetrating solder forms a eutectic structure on the surface of each metal, allowing the fixing part and the socket to be reliably joined by brazing. Further, it is possible to manufacture a joint fitting in which the solder is built up near the joint between the fixing part and the pipe part due to surface tension, thereby improving the fatigue strength of the joint.

Furthermore, by making the length of the notch slightly shorter than the press-fitting allowance, it is possible to manufacture a joint fitting in which the solder build-up is reliably formed in the vicinity of the joint portion.

〔Example〕

1 to 4 show a joint fitting 10 according to this embodiment. This joint fitting 10 is composed of a fixing part 12 and a socket 16.

As shown in FIGS. 2 and 4, the fixing part 1 of the joint fitting 10
2 is manufactured by processing a steel material into a cylindrical shape, and a through hole 18 is formed in the axial center.

A groove 20 is formed coaxially with the through hole 18 on the inner surface of the through hole 18 .

In this embodiment, the groove 20 is formed in the through hole 18 of the fixing part 12, but the groove 20 may not be formed. The enlarged diameter portion may be formed coaxially with the through hole 18.

This fixing part 12 is provided with a through hole 2OA that penetrates in a direction perpendicular to the axis of the fixing part 12, and this through hole 2OA opens toward the groove 20 from the outer periphery of the fixing part 12. has been done.

Furthermore, a groove 32 is formed on the outer circumferential surface of the fixing part 12 along the axial direction of the fixing part 12 . The groove 32 has a substantially semicircular cross section in a direction perpendicular to the axial direction of the fixing portion 12 . A cylindrical pin 34 is provided in the groove 32 of this fixing part 12.
is said to be able to be installed.

A socket 16 is attached to this fixed part 12.

A substantially cylindrical tube portion 14 whose diameter is reduced by drawing is formed at one end of the socket 16 .

Further, as shown in FIGS. 1 and 3A, a notch 26 having a depth A (shown in FIG. 3A) is formed on the outer circumferential surface of the tip of the tube I4 along the axial direction from the tip of the tube 14. is formed, and the length of the notch 26 is approximately the same as that of the through hole 2OA of the tube portion 14.
This is considered to be the press-fitting cost. This notch 26 is
A plurality of them are provided along the circumference of the outer peripheral surface.

When the tip of the tube portion 14 of the socket 16 is press-fitted into the fixing portion 18, if there is an extremely tight fit between the tube portion 14 and the through hole 2OA,
The pipe portion 14 is plastically deformed and the excess wall on the outer periphery is pushed to form the notch 2.
I'll be stopping by around 6. As a result, the gap between the outer periphery of the through hole 2OA and the pipe portion 14 is narrowed at the notch 26, but since the notch 26 is formed and the gap is made larger, the gap does not become extremely narrow. .

The through hole 2OA and the pipe portion 14 are joined by copper brazing. Copper solder (not shown), which is made by cutting a wire-shaped copper solder and bending it into a ring shape, is placed on the outer peripheral surface of the pipe portion 14 and heated together with the joint fitting 10. As a result, the molten copper solder 56 reliably penetrates into the gap between the through hole 2OA and the pipe portion 14, and as shown in FIG.
A eutectic structure 56Δ is formed by the copper solder 56 on the inner surface of A and the outer circumferential surface of the tube portion 14, and adhesive force acts to join the fixing portion 12 and the tube portion 14.

Further, near the joint between the fixing part 12 and the pipe part 14, the copper solder 56 adheres due to surface tension to form a build-up.

On the other hand, as shown in FIG. 4, this socket 16 is provided with a communication hole 22 along its axis. In addition, the communication hole 22
A reduced diameter portion 24 is formed near the boundary between the tube portion 14 and the socket 16, and the diameter is further reduced in the tube portion 14 to reach the tip portion 14A.

A nipple 28 is inserted into the socket 16 from the opening side of the socket 16 toward the reduced diameter portion 24 of the communication hole 22 and joined by copper brazing.

As shown in FIGS. 2 and 4, one end of the flexible hose 30 is inserted into the socket 16 of the joint fitting 10 manufactured in this way, and the nipple 28 is inserted into the inner surface of the flexible hose 30. .

This flexible hose 30 can be attached to the fitting fitting 1 by caulking the outer circumference of the socket 16 (as shown in FIG. 4).
0.

The other end of the flexible hose 30 is connected to a mask cylinder of a brake (not shown).

As shown in FIG. 4, the joint fitting 10 to which the flexible hose 30 is connected is fixed to a cylinder block 36 of a brake caliper 60 of a front wheel of a vehicle (not shown). This fixing is achieved by arranging copper washer gaskets 38 on both sides of the through hole 18 of the fixing part 12 in the axial direction, inserting union bolts 40 into these copper washer gaskets 38 and the through hole 18, and then attaching the union bolts 40 to the cylinder block 36. This is done by screwing into a screw thread 48A formed in an engagement hole 48 drilled in the .

When fixing the joint fitting 10 to the cylinder block 36, drive the tip of the pin 34 into the rotation prevention hole 46 formed in the cylinder block 36, fit the pin 34 into the groove 32 of the fixing part 12, and then tighten the union bolt 40. By screwing together, the cylinder block 3B and the joint fitting 10 are fixed.

This pin 34 is attached to the groove 32 of the joint fitting 10 to which the flexible hose 30 is joined, and then
may be fixed to the cylinder block 36.

On the other hand, the union bolt 40 has a through hole 1 in the fixing part 12.
A communication hole 42 is formed from a portion located in the groove 20 portion in the groove 8 to the tip. In addition, the cylinder block 36
A communication hole 48B is formed from the engagement hole 48 to the cylinder 62.

Brake oil (not shown) inside the flexible hose 30 is sent into the cylinder 62 through the communication hole 22 of the fitting 10, the groove 20, the communication hole 42 of the union bolt 40, and the communication hole 48B of the cylinder block 36. Since the fitting 10 is tightly joined by copper brazing, even if high pressure of brake oil is applied, the fitting 1
0 will not cause leakage.

According to the manufacturing method of the joint fitting 10 according to the present embodiment, the pipe portion 14 in which the notch 26 is formed is press-fitted into the through hole 2OA of the fixed portion 12 of the joint fitting 10 and copper brazed. It is possible to obtain a joint fitting 10 in which the socket 16 is tightly joined.

In this example, the tube portion 14 with a diameter of 7 mm is connected to the through hole 2OA.
When inserting 3 mm into the tube and brazing the copper, the depth A of the notch 26 (shown in Fig. 3A) is set to 0.03 to 0.05 mm, and six locations are provided on the outer circumferential surface of the pipe portion 14 to achieve the optimum condition. I was able to perform copper brazing.

Further, as a modification of this embodiment, the depth A of the notch 26 is
(shown in FIG. 3A) is 0.03 to 0.05 mm, and the length of the tube 14 is 2 mm to 2.5 mm from the tip of the tube 14.
It is also possible to provide six locations on the outer peripheral surface of the.

In this case, a copper solder (not shown) made by cutting a linear copper solder and bending it into a ring shape is placed on the outer circumferential surface of the pipe portion 14, and a copper solder (not shown) is placed on the inner surface of the through hole 2OA. There is.

Since the notch 56 of the tube portion 14 is short, the fit is tight near the injection port of the through hole 2OA, and even if the ring-shaped copper solder melts, a large amount of it will not seep into the gap between the through hole 2OA and the tube portion 14. First, a build-up is formed between the tube portion 14 and the fixed portion 12. Moreover, the copper solder disposed inside the through hole 2OA reliably penetrates into the gap between the through hole 2OA and the tube portion 14, since there is no part where the gap between the through hole 2OA and the tube portion 14 is extremely narrow.

As a result, the through hole 2O of the fixing part 12 shown in FIG. 3B
A eutectic structure 56A is formed by the copper solder 56 on the inner surface of A and the outer peripheral surface of the tube portion 14, and adhesive force is exerted on the fixing portion 1.
2 and the socket 16 can be tightly and firmly joined. In addition, the copper solder 56 can adhere to the vicinity of the joint between the fixing part 12 and the tube part 14 due to surface tension to form a build-up.

As described above, copper brazing can be reliably performed by a simple process of forming the notch 26 on the outer circumferential surface of the tube portion 14 of the socket 16, and a joint fitting 10 without defective joints can be manufactured.

Incidentally, as shown in FIG. 6, it is also possible to form a notch 26A on the inner surface of the through hole 20A of the fixing part 12. In this embodiment, the notch 26 is formed in the tube portion 14, but the same effect can be obtained even if the notch 26A is formed in the through hole 2OA of the fixing portion 12.

〔Effect of the invention〕

As explained above, according to the present invention, by a simple process of forming a plurality of notches on the outer circumferential surface of the tube portion or the inner surface of the hole in the fixing portion, a desired distance between the hole in the fixing portion and the inserted tube portion can be formed. There is a gap between Thereby, an excellent effect can be obtained in which the fixing part and the pipe part can be reliably joined by brazing to manufacture a joint fitting.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the main parts of a joint fitting to which the present invention is applied, FIG. 2 is a perspective view of a joint fitting according to this embodiment, and FIG. 3A is a sectional view taken along the line 3A-3A in FIG. 1. Figure 3B is Figure 13
4 is a cross-sectional view showing the attachment of the fitting according to this embodiment; FIG. 5 is a perspective view similar to FIG. 2 showing the conventional example; FIG. FIG. 1 is a sectional view of a main part taken along the line 6-6 in FIG. 1, showing a modification of the present embodiment. DESCRIPTION OF SYMBOLS 10... Joint fitting, 12... Fixing part, 14... Pipe part, l6... Socket, 2OA... Through hole, 26... Notch, 56A... Eutectic structure.

Claims (1)

[Claims] (1) A method for manufacturing a fitting in which a cylindrical tube is inserted into a hole drilled in the outer peripheral surface of a fixing part and joined by brazing, the wall surface forming the hole of the fixing part and the tube part A method for manufacturing a fitting, characterized in that a plurality of notches are provided in at least one of the outer circumferential surfaces of the fitting, and the pipe portion is inserted into the hole of the fixing portion and joined by brazing.