JP3014491B2 - Method of manufacturing eye joint by cold rolling - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to a metal having a relatively small diameter of about 20 m / m or less, which is provided as an oil supply / supply path for an automobile or various machines, equipment, and devices. The present invention relates to a method for manufacturing an eye joint with a branch pipe by cold rolling, which is frequently used as a fixing means at a connection end of a pipe or a flexible tube.

[0002]

2. Description of the Related Art Conventionally, as a manufacturing method of this kind, for example, as shown in FIGS. 11 and 12, a pair of dies (12) (12 ₁ ) having a concave groove is cut into a short dimension. Set the tube as a material, press it in the axial direction to bulge the peripheral side wall (11 ') outward, cut the cut surfaces on both sides in parallel, and shape it to form an eye joint ring. (1
1) is formed, and then a through hole (13) communicating with the inside is provided in a part of the peripheral side wall by cutting, or the whole is formed by cutting, and then the through hole (13) is formed in the inner peripheral portion by cutting. It was formed by brazing (W) a branch tube body (14) having a stepped portion (14 ') on the side of the opening end.

[0003]

However, in such a conventional technique, parallel cutting work on the bearing surface of the eye joint ring body (11), drilling work in the through hole (13), and further branching. The manufacturing process is troublesome due to the cutting work including the stepped part (14 ') in the cylindrical body (14) and the assembling and brazing (W) work with the branch cylindrical body (14) in the through hole (13). Not only does this cause a drop in productivity, but also due to the reheating and local overheating of the product during brazing (W) and subsequent brazing with pipes (not shown), (14) The mechanical strength is deteriorated near the connection part on the side, cracks are generated in combination with the vibration under the arrangement state, and breakage occurs, and also, as a material due to a decrease in the yield of the material due to the cutting process, The product price cannot be reduced for the use of the tube, and FIG.
As shown in the figure above, the periphery of the mounting hole on both sides is tapered, which causes thermal deformation due to heating during soldering (W), so that a sufficient seating surface cannot be obtained and In such a case, a large number of man-hours are required, and the yield of the material is extremely poor.

[0004] The present invention has been made in view of the above-mentioned problems of the prior art, and is manufactured by cold rolling with a die, a punch, and a pin in each step, thereby greatly reducing the number of cutting processes. Eliminate waste of material, make it cheap by easy production, and secure mechanical strength against tightening at the periphery of the mounting hole in terms of quality,
It is still another object of the present invention to provide a method of manufacturing an eye joint by cold rolling that can prevent cracks and breakage by an integrated product shape.

[0005]

In order to achieve the above object, according to the present invention, a metal pillar having parallel flat surfaces in a cross section is used as a raw material, and a first punch tool is used to slightly adjust a shaft in a concave groove of a first die. A first step of pressing the core in the direction of the core to set the outer surface;
A second step of extruding the rear container in the axial direction with a punch tool to form a hollow bottomed cylinder; attaching the bottomed cylinder to a third die, and making the bottom surface arc-shaped by a third punch tool. And a third step of forming a stepped portion on the inner peripheral surface on the opening end side of the cylindrical portion; attaching the bottomed cylindrical body to the fourth die, inserting a punch into the cylindrical body, and using a fourth punch tool. A fourth step of forming the cylindrical body portion into a short tubular shape and shaping the bottom surface into a single-layered arc surface; and attaching the bottomed cylindrical body to the fifth die and inserting the punch, setting the bottom surface to the fifth shape. A fifth step of forming into a sphere by a punch tool; and a sixth step of forming an assembling hole by forming an assembling hole through the parallel flat surface left facing the outer surface. The gist is a method of manufacturing a joint, and the drilling of the mounting hole is further performed by pressing or cutting. Ri performed, also those subjected to further cutting the outer surface of the parallel flat surface.

[0006]

Since the present invention is based on such a manufacturing method, waste of material can be reduced by extremely reducing the number of cutting steps, the manufacturing cost can be reduced by easy manufacturing, and sufficient mechanical strength at the periphery of the mounting hole can be obtained. The strength is obtained, and a highly accurate product can be obtained by the integral product shape.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1a to FIG. 5a are cross-sectional views showing a manufacturing process of the present invention, and FIG. 1b to FIG. 6, FIG. 6 is a perspective view of the material obtained from FIG. 5, FIG. 7 is an enlarged plan view of a metal column piece as a material of the present invention, FIG. 8 is a sectional view taken along line VIII-VIII of FIG. FIG. 9 is an enlarged plan view of an eye joint manufactured according to the present invention, and FIG.
First, as a first step, the extruded material is cut, and has a flat surface (1 ₁ ′) and (1 ₁ ″) parallel to each other in cross section, for example, a drum shape (FIG. 8A) and a square shape (FIG. 8B). ) Or a chamfered square (FIG. 8c) shaped metal pillar piece (1 ₁ ) as a material is placed in the groove of the first die (2 ₁ ) shown in FIG. to form the curved corner is pressed slightly axis direction by 3 _1), a flat surface parallel to flattening (1 1 _'), provided (1 1 _"). Next, as a second step, as shown in FIG.
₁₎ second die (2 ₂₎ set to the outer surface in a state of mounting a second punch member (3 ₂₎ by the rear container extrusion allowed a flat surface parallel to the axial direction (1 2 _'), ( 1 ₂ ")
, For example, a hollow bottomed cylindrical body having a drum-shaped cross section (1 ₂ )
To form Then, as a third step, as shown in FIG. 3, the bottomed cylindrical body (1 ₂ ) is attached to a third die (2 ₃ ) having a concave portion having a curved surface at the bottom by reversing the setting direction and corresponding to the tip. Having a curved surface and an enlarged diameter portion in the middle
A flat surface parallel with the insertion of the punch tool _{(3 3) (1 3} '),
(1 ₃ "), leaving the bottom surface in an arc shape and the cylindrical body (4)
A stepped portion (4 ') is preformed on the inner peripheral surface on the opening end side of the portion. Further, as a fourth step, as shown in FIG.
₃₎ re-sets the direction opposite the mounting to the fourth die (2 _4), the cylindrical body (4) the forward tube extrusion Pounds a fourth punch tool by inserting a punch (5) in the interior (3 ₄₎ The tip of the cylindrical body is made to be a short tube, and the inner stepped part (4 ') is rough-finished so that the bottom surface is shaped into a more circular surface (6). At this time, the parallel flat surfaces (1 ₄ ′) and (1 ₄ ″) are left as they are. Subsequently, the bottomed cylindrical body (1 ₄ ) is subjected to a fifth step as a spherical surface as shown in FIG. in the fifth die (2 ₅₎ attached to the set state in which the insertion of the punch (7) having a portion, in which allowed to shaping the bottomed face fifth punch tool ₍₃₅₎ by cross section drum-shaped spherical (See FIG. 6), and is formed by drilling an assembling hole (8) through the parallel flat surface ( ₁₅ ') and ( ₁₅ ") which are left as a final step after removal. Will be done.

Incidentally, all of the steps up to the fifth step are automatically processed by a multi-stage cold heading machine using a parts former. Further, the assembling hole (8) may be formed by continuous parts forming or by cutting. Further, the parallel flat surfaces ( ₁₅ ′) and ( ₁₅ ″) may be subjected to a cutting process on the outer surface after the parts former to further improve the sealing performance.

[0009]

As described above, according to the method for manufacturing an eye joint by cold rolling according to the present invention, the metal column piece (1) having parallel flat surfaces (1 ₁ ′) and (1 ₁ ″) in cross section is provided. _{Since 1} ) is used as a material and formed by cold rolling and drilling of the assembling hole (8) in the subsequent five steps, the number of cutting steps is extremely reduced, material waste is eliminated, and the cost is reduced by easy manufacturing. In addition, sufficient mechanical strength is obtained at the peripheral edge of the mounting hole (8), and a highly accurate product can be obtained by the integral product shape.

[Brief description of the drawings]

FIG. 1a is an explanatory view by a cross section showing a first step in manufacturing an embodiment of the present invention.

1b is a cross-sectional view of the material of FIG. 1a along the line II.

FIG. 2a is a view showing a second step.

2b is a cross-sectional view of the material of FIG. 2a, taken along line II-II.

FIG. 3a is a view showing a third step.

3b is a cross-sectional view of the material of FIG. 3a, taken along line III-III.

FIG. 3c is a cross-sectional view taken along the line III′-III ′ of FIG. 3a.

FIG. 4a is a view showing a fourth step.

4b is a cross-sectional view of the material of FIG. 4a along the line IV-IV.

FIG. 4c is a cross-sectional view taken along the line IV′-IV ′ of FIG. 4a.

FIG. 5a is a view showing a fifth step.

5b is a cross-sectional view of the material of FIG. 5a along the line VV.

FIG. 5c is a cross-sectional view taken along line V'-V 'of FIG. 5a.

FIG. 6 is a perspective view of a material obtained in a fifth step.

FIG. 7 is an enlarged plan view of a metal column piece as a material of the present invention.

8a is a sectional view taken along line VIII-VIII of FIG. 7;

FIG. 8b is a view corresponding to FIG. 8a of another embodiment of the metal column piece.

FIG. 8c is a view corresponding to FIG. 8a of still another embodiment.

FIG. 9 is an enlarged plan view of an eye joint manufactured according to the present invention.

FIG. 9 is a sectional view taken along line XX of FIG. 9;

FIG. 11 is an explanatory diagram illustrating a cross section showing a manufacturing method of a conventional example.

FIG. 12 is a longitudinal sectional view of the eye joint manufactured according to FIG. 11;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ₁ Metal pillar piece 1 ₂ Bottomed cylinder 1 ', 1 "Flat surface 2 ₁ 1st die 3 ₁ 1st punch tool 2 ₂ 2nd die 3 ₂ 2nd punch tool 2 ₃ 3rd die 3 ₃ 3rd punch Tool ₄ 4th die 3 ₄ 4th punch 2 ₅ 5th die 3 ₅ 5th punch 4 Cylindrical body 4 ′ Stepped portion 5 Punch 6 Arc surface 7 Punch 8 Assembly hole

Claims (3)

(57) [Claims] A flat surface (1 ₁ ′) parallel in cross section;
Using a metal column piece (1 ₁ ) having (1 ₁ ") as a material, the first
A first step of slightly pressing the concave groove portion of the die (2 ₁ ) in the axial direction with the first punch tool (3 ₁ ); attaching the metal column piece to the second die (2 ₂ ), 2 punch tool (3 ₂₎ a second step and to form a hollow bottomed tubular body (1 ₂₎ brought behind the container extrusion in the axial direction by; in a bottomed cylindrical body 3 die (2 ₃₎ with mounting the third punch member (3 ₃₎ the bottom of the arc shape, and a third step of forming stepped portions (4 ') on the inner peripheral surface of the cylindrical body (4) opening end side of; Yes Attach the bottom cylinder (1 ₃ ) to the fourth die (2 ₄ ),
Insert the punch (5) into the cylinder (4) and insert the fourth punch (3
₍₄ ) a _{fourth step} of forming the cylindrical portion into a short tubular shape and shaping the bottom surface into a single-layered arc surface (6);
Left to face the outer surface; ₄₎ fifth step and shaping the bottom surface in a state of inserting the punch (7) attached to the fifth die (2 ₅₎ spherically by the fifth punch tool ₍₃₅₎ A sixth step of forming an assembling hole (8) by penetrating the parallel flat surfaces ( ₁₅ ') and ( ₁₅ "). Manufacturing method of the joint. 2. The method for manufacturing an eye joint by cold rolling according to claim 1, wherein the assembling holes (8) are formed by pressing or cutting. 3. The method for producing an eye joint by cold rolling according to claim 1, wherein the outer surfaces of the parallel flat surfaces ( ₁₅ ′) and ( ₁₅ ″) are further cut.