JPS625697B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a perforated component having a narrow groove provided on the outer periphery of the main body.

By the way, as a perforated part having a narrow groove on the outer periphery of the main body, for example, a cap nut-shaped screw part A ₁ embedded in a knob K made of synthetic resin as shown in FIG. 1 forms the main body 1. External body 2 next to the opening
A narrow groove 4 is provided between the main body and the other internal body 3 to prevent the knob K from coming off, and an inner hole 5 which is a screw hole is provided inside the main body.
A blind hole 6 with a diameter larger than the inner hole is formed in the deep part, and 7 is a hole 6 that is larger in diameter than the inner hole.
This is a serration provided on the outer periphery of the Also, anchor nut parts for caulking nuts shown in Fig. 1 2.
A ₂ is an outer body 2 in which a serration 7 and a collar 8 are provided in the main body 1 which is fitted into a hole H provided in a plate material, and an inner body 3 which is fitted into the outer body 1 when it is cut. A narrow groove 4 for separation is provided between the
Furthermore, an inner hole 5 is formed in the outer body 2, and a through hole 9 for a screw hole, which is smaller in diameter than the inner hole, is formed in the inner body 3. Note that the narrow grooves 4 of the upper perforated parts A ₁ and A ₂ are both formed in a tapered shape with a diameter gradually decreasing from the outer periphery of the lower body 3. It may have any shape or other cross-sectional shape.

In this way, it is difficult to form the entire shape of the perforated parts A ₁ and A ₂ in which the narrow groove 4 is provided on the outer periphery of the main body 1 by forging processing alone, apart from tapping processing. Since the narrow groove 4 is formed by rolling or cutting, the process becomes complicated and costs increase.

In the present invention, the entire shape of such a perforated part can be formed sequentially by forging process, and the embodiment shown in FIGS. 2 and 3 will be described below.

Figures 2 1 to 4 show the perforated parts shown in Figure 1 1.
This shows the process of forming the entire shape of A1 in stages, excluding the tapping of the inner hole ₅ .

First, as shown in FIG. 2, a material a of a required length is cut from a suitable long bar material, and this is supplied to the forging die ₁₁₁ in the first forging stage, and then the forging punch ₁₂₁
Pressure is applied in the axial direction to adjust the outer diameter D ₁ of the perforated part.
A primary molded product is obtained in which the shaft portion 1a is equal to the outer diameter of the main body 1 at _A1 .

Next, this primary molded product is extruded from a forging die ₁₁₁ with a knockout pin ₁₃₁ , and is then extruded as shown in FIG.
The forging punches _122a were guided by the outer cylinder _122b and pressed into the forging die ₁₁₂ at the second forging stage shown in FIG _. An outer half 2' having a cavity 5a opening therein and an inner half 3' having a bottom 1b are formed, and the material displaced by the formation of the cavity 5a is pushed out to the end of the mouth. , to obtain a secondary molded product with increased length in the axial direction,
Therefore, the inner diameter d ₁ of the cavity 5a is made equal to the inner diameter of the inner hole 5 of the perforated part A ₁ .

The above secondary molded product is pulled out from the cavity 5 by retracting the forging punch 12 ₂ a, and then the outer cylinder 1
2 While retracting with ₂ b, knockout pin 13
₂ , it is extruded from the heading die 11 ₂ , and then
is transferred to the heading die ₁₁₃ of the third heading stage. In this forging step, the inner punch 12 ₃ a of the forging punch having a double structure is first inserted into the cavity 5 a of the secondary molded product, and then the entire molded product is inserted with the outer punch 12 ₃ b. The outer half 2' formed in the previous heading step is pressed into the forging die ₁₁₃ to form an outer body 2 of outer diameter D ₁ provided with an inner hole 5 of inner diameter d ₁ in the perforated part A ₁ . In addition, the inner half 3' has an outer diameter approximately equal to the outer diameter of the narrow groove 4.
The small diameter portion 4' is pressed so as to have a diameter of D ₂ , and the inner punch 1 is inserted into the inner hole 5.
2 ₃ a has a thickness greater than the wall thickness of the side wall S formed between the outer periphery of the small diameter portion 4' and the inner hole 5 by being further press-fitted into the small diameter portion 4'. Thus, a tertiary molded product having a bottom wall 1C is obtained. Note that the inner punch 12 ₃ a used in this forging step has the inner diameter of the cavity 5 a formed in the previous step.
The outer diameter is equal to _d1 , and a large number of protrusions (not shown) are formed in the axial direction on the inner periphery of the mouth of the forging die ₁₁₃ for forging the outer body 2. Accordingly, serrations 7 can be formed on the outer periphery of the external body 2.

The thus obtained tertiary molded product is pressed by the outer punch 12 ₃ b while being pressed by the inner punch 12 3 b.
_3a is pulled out and then retreated together with the outer punch, and then extruded from the forging die ₁₁₃ by the knockout pin ₁₃₃ and transferred to the forging die ₁₁₄ of the fourth forging stage shown in FIG. 2.

The heading die ₁₁₄ used in this heading stage is
The outer diameter D ₁ of the outer body 2 in the part A ₁ is made equal to the outer diameter D 1 of the outer body 2 . Therefore, the inner punch 12 ₄ a with an outer diameter that maintains the inner hole 5 formed as the inner diameter d ₁ in the previous step is inserted into the outer cylinder. The inner punch 12 ₄ a is inserted into the inner hole 5 while being guided by the inner punch 12 ₄ b.
When the bottom wall 1C of the small diameter portion ₄ ' formed in the third forging step is pressurized from the inside and outside in the axial direction by the knockout pin 134, the bottom wall 1C is pressed outward in the forging die ₁₁₄ . As it is buckled and deformed to expand into a flat shape, the end of the small diameter portion 4' is formed in the inner body 3 with the outer diameter _D1 of the main body ₁ in the perforated part A1. Furthermore, since the inner thickness of the bottom wall 1C to be subjected to buckling deformation was larger than the wall thickness of the side wall S, the bottom wall 1C would flow in the outer circumferential direction due to the expansion deformation of the bottom wall 1C. A blind hole 6 having a diameter larger than the inner diameter _d1 of the inner hole 5 is formed around the tip of the inner punch _124a , and at the same time, the smaller diameter formed in the previous step is formed by forging deformation of the inner body 3. As the end portion of the portion 4' is expanded by buckling deformation and the inner body 3 is forged as described above, the small diameter portion 4' remaining between the outer body 2 and the inner body 3 is removed. The constricted groove 4 having the outer diameter D ₂ in the perforated part A ₁ is formed by deforming the hole part A 1 . By providing circular protrusions 12' and 13' as shown in the figure on the opposing end surfaces of the inner punch _124a and the knockout pin ₁₃₄ , the buckling deformation can be effectively carried out.

The quaternary molded product formed by heading as described above has an outer body 2 and an inner body 3 of a main body ₁ with an outer diameter of D1.
A narrow groove 4 with an outer diameter D ₂ is provided between the outer body 2 and an inner hole 5 with an inner diameter d ₁ in the outer body 2 .
It has a shape in which a blind hole 6 with a diameter larger than the inner hole is provided inside, and the inner punch _124a is pulled out and the outer punch 12 is removed.
After retreating with _4b , this molded product is taken out from the forging die ₁₁₄ with the knockout pin ₁₃₄ ,
When the inner hole 5 is tapped, a perforated part _A1 as shown in FIG. 1 is obtained.

Next, Figs. 3 1 to 5 show the perforated parts shown in Fig. 1 and 2.
This refers to the step-by-step process of forming the entire shape of _A2 , excluding the tapping process, by heading.

The steps shown in the forging steps 1 to 4 excluding FIG. 3 are different from the steps shown in the forging steps in FIGS. 2 1 to 4 described above. The inner punches 12 ₃ a and 12 ₄ a have protrusions 12 ₃ c and 12 4 c each having the same diameter and smaller diameter than the inner diameter d ₁ at the tips of the inner punches 12 3 a and 12 _{4 a} . ₁₁₄ , the knockout pins ₁₃₁ to ₁₃₄ , and the forging punches ₁₂₁ , _122a , _122b in FIGS. 31 and 2 are the same as those shown in FIG. 2, respectively. It is also indicated by a code.

That is, in the first forging stage shown in FIG. 3, the outer diameter of the main body 1
A shaft portion 1a having a diameter D ₁ is formed, and in the next second forging step, a cavity 5a having an inner diameter d ₁ is formed with one end open.
The outer half 2' with the bottom 1b and the inner half 3' with the bottom 1b each have an outer diameter _D1 .

However _, in the third _forging stage shown in _{FIG .} In this step, an outer body 2 having an outer diameter D ₁ having an inner hole 5 having an inner diameter d ₁ is formed, and a bottom wall 1C is formed at the innermost part of the small diameter portion 4' formed to have an outer diameter D ₂ . A recessed portion 5b having a wall thickness greater than that of the side wall S is formed.

_The above-mentioned tertiary molded product is inserted into the forging die ₁₁₄ in the _fourth forging stage shown in FIG. The bottom wall 1 of the small diameter portion ₄ ' formed in the pre-heading stage is
When C is pressurized from the inside and outside in the axial direction, the flesh around the bottom wall is buckled and deformed so as to expand outward in a flat shape, and the inner body 3 has an outer diameter of D ₁ . At the same time as the bottom wall 1C is formed, as the meat of the bottom wall 1C flows in the outer circumferential direction, a bag is formed on the outer periphery of the protrusion 12 ₄ c in the inner punch 12 ₄ a so that the upper part is narrowed 6'. The hole 6 is forged, and by forging the inner body 3, the small diameter portion 4' between the inner body 3 and the outer body 2 formed in the previous step is reforged so as to become the narrow groove 4. The next molded product is obtained. Note that the diameter of the tip projection 12 ₄ c of the inner punch is determined so that the inner diameter of the blind hole 6 formed in this forging step is smaller than the inner diameter d ₁ of the inner hole 5 formed in the outer body 2. Inner punch 12 ₄ a
The diameter of the protrusion 12 ₄ c may be the same as that of the protrusion 12 4 c, but as shown in the figure, the diameter of the protrusion 12 4 c is smaller than the inner diameter d ₁ .
There is no problem even if it is formed to have a diameter larger than that of the protrusion 12 ₄ c.

The thus obtained quaternary molded product is produced by pulling out the inner punch 12 ₄ a and then removing the outer punch 12 ₄ b.
After the molded product is withdrawn from the forging die ₁₁₄ by the knockout pin ₁₃₄ , it is transferred to the fifth forging stage shown in FIG. 3.

The heading die ₁₁₅ used in this heading stage is
The outer diameter D1 of the main body 1 in the perforated part _A2 is made equal to the outer diameter _D1 , and a receiving cylinder _13'5 through which a knockout pin ₁₃₅ is inserted is inserted inside, and the forging punch is further inserted into the above-mentioned main body. The outer diameter D of the guide punch ₁₂₅ is inserted into the inner _hole 5 of the upper body 2 at the tip of the large diameter punch _125a , which has an outer diameter D larger than 1, and the inner diameter of the blind hole 6 formed in the forging step. By integrally forming the three stages of the trimming punch _125c , which has a large diameter and a smaller diameter than the inner diameter _d1 of the inner hole 5, the fourth molded product formed in the pre-heading step can be transferred to the forging die. In ₁₁₅ , the large-diameter punch _125a and the guide punch _125b press the collar 8 into an overhanging shape on the upper end of the outer body 2, and
A through hole 9 having a smaller diameter than the inner hole 5 is formed in the inner body 3 by the trimming punch _125c , and the peripheral wall 9' that had formed the blind hole 6 is punched downward from the inside of the receiving tube _13'5 . That's what happens.

The quintic molded product formed by heading as described above has an outer diameter D of ₁ between the outer body 2 and the inner body 3.
A narrow groove 4 with an outer diameter D ₂ is provided, a collar 8 is provided at the end of the outer body 2, and a serration 7 formed in the third forging step as described above is provided on the outer periphery. 3 is forged into a shape in which a through hole 9 having a diameter smaller than the inner diameter d ₁ of the inner hole 5 is provided. Therefore, trimming punch 1 at the tip of the forging punch
2 ₅ c is retreated to the outside of the heading die 11 ₅ ,
By advancing the knockout pin ₁₃₅ and the receiver _13'5 , they are taken out to the outside and tapped into the through hole 9, resulting in a perforated part as shown in FIG.
A ₂ is obtained.

As described above, according to the present invention, a perforated component is manufactured which has a constriction groove on the outer periphery between the outer body and the inner body constituting the main body, and has an inner hole with at least one end opened in the outer body. In this process, a material of an appropriate length is pressurized in the axial direction to forge a shaft portion of the required outer diameter, and a cavity of the required inner diameter is formed from one end of this shaft portion to an appropriate depth, and then this cavity is By narrowing the other inner half of the provided outer half of the shaft to a smaller diameter part of the required outer diameter, the outer half is forged into the outer body of the main body with the required inner hole. The cavity is formed to a position where a bottom wall with a thickness greater than the thickness of the side wall formed between the outer periphery of the small diameter part and the cavity is provided, and then the bottom wall is formed from the inside and outside in the axial direction. By applying pressure, the inner half is expanded to a required outer diameter, thereby forging the inner body of the main body, and the small diameter portion remaining between the inner body and the outer body is expanded to the required outer diameter. Since the narrow groove is formed on the outer periphery of the main body, it is possible to form a perforated part with a narrow groove on the outer periphery of the main body, including an inner hole opened at one end, only by heading processing. Therefore, whereas conventional narrowing grooves are created by rolling or cutting,
This simplifies the manufacturing process and allows the above-mentioned perforated parts to be manufactured with high efficiency and at low cost.

[Brief explanation of the drawing]

1 and 2 are partially cutaway side views showing examples of perforated parts to which the present invention is applied; FIG. 4 is a cutaway side view of main parts shown in order. a is the material, 1 is the main body, 1a is the shaft, 2c is the bottom, 2' is the outer half, 3' is the inner half, 4' is the small diameter part,
2 is an external body, 3 is an internal body, 4 is a narrow groove, 5' is a cavity, 5 is an inner hole, and S is a side wall.

Claims (1)

[Claims] 1 Press a material of an appropriate length in the axial direction to forge a shaft portion of the required outer diameter, form a cavity of the required inner diameter from one end of this shaft portion to an appropriate depth, and then provide this cavity. By narrowing the other inner half to the outer half of the shaft so as to have a smaller diameter than the required outer diameter, the outer half becomes the outer body of the main body having the required inner hole. The cavity is formed to a position where a bottom wall having a thickness greater than the thickness of the side wall formed by the outer periphery of the small diameter part and the cavity is provided, and then this bottom wall is pressurized from the inside and outside in the axial direction. By tightening the inner half, the end portion of the inner half is enlarged to the required outer diameter to form the inner body of the main body, and the small diameter portion remaining between the inner body and the outer body is expanded to the required outer diameter. A method for manufacturing a perforated part provided with a narrow groove, the method comprising forming a narrow groove.