KR101480440B1 - Making method of pan nut - Google Patents

Abstract

The present invention relates to a method of manufacturing a fan nut, and more particularly, to a method of manufacturing a fan nut comprising a body portion, a flange portion, and a bolt hole, wherein three widthwise directions of the steel sheet material are drawn in a basic shape to be a fan nut, A drawing step of continuously drawing three points in the width direction; A basic shape formed by the drawing is subjected to a rough forging operation successively along the longitudinal direction with one set of three widthwise positions of the steel plate material by a forging punch to form a first body portion and a flange portion of the fan nut, Forging step; A shaping step of sequentially shaping the fan nut having the body and the flange portion; A second forging step of performing a forging operation by a forging punch to form a bolt hole in the shaping operation completed fan nut; A chamfering step of chamfering a bottom surface of the fan nut on which the bolt hole is formed; A hole piercing step of forming a thread in the bolt hole; A side notching step of forming a mold groove by a press-fit punch on a flange portion of the fan nut having completed the hole piercing; And a trimming step of removing an unnecessary portion of the fan nut on which the mold recess is formed. The mechanical property of the fan nut is improved by the forging operation and the production speed is increased, which is suitable for mass production.

Description

Technical Field [0001] The present invention relates to a manufacturing method of a fan nut,

More particularly, the present invention relates to a method of manufacturing a fan nut. More particularly, the present invention relates to a method of manufacturing a fan nut, and more particularly, to a method of manufacturing a fan nut by manufacturing a fan nut through a forging operation after a step of drawing a steel sheet material, The present invention relates to a method of manufacturing a fan nut, which is capable of mass production of a fan nut by continuously operating a nut, thereby improving productivity.

BACKGROUND ART [0002] As a background art of the present invention, there is a 'coupling nut and a manufacturing method thereof' described in Patent Documents 1 and 2 in patent documents of prior art documents. The fastening nut is the same as the fan nut of the present invention. The fastening nut is used to assemble an electric and electronic product such as a PDP, an LCD, and the like, and has a cylindrical body 1 and a flange And a bolt hole (3) formed through the lower center portion of the body portion (1).

As a method of manufacturing the fastening nut, there are known methods such as a cutting method, a plate material forming method, and a method of inserting a nut. Among them, a method of producing a fastening nut and a method of inserting a nut There is a problem that a fan nut is manufactured by a plate material forming process. In the method of manufacturing the fan nut by the plate material forming process, the steel plate material is cut into a plurality of small plates having a small size to be a fan nut, And a method of manufacturing the fan nuts through various steps such as blanking, drawing, and plastic working.

However, in the conventional method of manufacturing the fan nuts by the plate material forming process, since the fan nuts are made only by the drawing process of expanding the steel material, there is a problem that the mechanical properties such as strength are somewhat lowered. So that the productivity is lowered because the production speed is somewhat delayed.

That is, in the case of the conventional transfer press used in the drawing process for manufacturing the fan nuts, the productivity is significantly lower than that of the forging press on which the sequential transfer die used in the present invention is mounted, the expensive equipment of the transfer press, It is difficult to replace the model mold for manufacturing the nut, and the replacement time is also long. Furthermore, since the transfer press is set up one by one for each process of the fan nut in the bolster for setting the base material, productivity is low.

Further, in the case of manufacturing the fan nut in the above-described manner, a mold groove is formed in the flange portion of the fan nut in order to achieve a mold-bonding force with the material to be coupled to the fan nut. However, When the fan nut is coupled to the material to be bonded by the flared protrusion formed to be pushed toward the negative side, fine cracks are generated between the fingered material and the fan nut by the flared protrusions, and this fine gap is provided as a cause of the beam gap, It becomes a problem.

Korean Patent No. 10-1080149 Korean Patent No. 10-1162340

SUMMARY OF THE INVENTION The present invention has been made in order to overcome the above problems, and it is an object of the present invention to provide a forging device for a forging machine, It is another object of the present invention to provide a method of manufacturing a fan nut in which the mechanical properties of a fan nut are improved by manufacturing a fan nut by a forging operation by forging punch without manufacturing the fan nut by the method.

Another object of the present invention is to provide a method of manufacturing the fan nuts by performing the manufacturing of the fan nuts at three positions in the width direction of the steel sheet material, And a method for manufacturing a fan nut is provided.

It is still another object of the present invention to provide a fan nut which, when forming a mold groove for molding with a material to be fused by a press-fitting punch in the flange portion of the fan nut, And a minute gap is not generated between the flange and the coupling member.

In order to achieve the above object, the present invention provides a method of manufacturing a fan nut including a body portion, a flange portion, and a bolt hole, the method comprising the steps of: A drawing step of continuously drawing three portions in the width direction along the longitudinal direction; A basic shape formed by the drawing is subjected to a rough forging operation successively along the longitudinal direction with one set of three widthwise positions of the steel plate material by a forging punch to form a first body portion and a flange portion of the fan nut, Forging step; A shaping step of sequentially shaping the fan nut having the body and the flange portion; A second forging step of performing a forging operation by a forging punch to form a bolt hole in the shaping operation completed fan nut; A chamfering step of chamfering a bottom surface of the fan nut on which the bolt hole is formed; A hole piercing step of forming a thread in the bolt hole; A side notching step of forming a mold groove by a press-fit punch on a flange portion of the fan nut having completed the hole piercing; And a trimming step of removing an unnecessary portion of the fan nut on which the mold recess is formed.

In the first forging step, it is preferable that the forging work is performed through several steps with a forging punch having various shapes so as to be close to the shape of the body portion and the flange portion of the fan nut in the basic shape of the fan nuts by the drawing step.

It is preferable that, when the mold groove is formed in the flange portion of the fan nut by the press-fitting punch in the side notching step, the mold projection is not formed on the opposite side of the mold groove while forming the through hole in the mold groove.

According to the method of manufacturing a fan nut of the present invention, since the fan nut is manufactured by forging the steel sheet material, which is the base material of the fan nut, the mechanical property value such as strength is improved more than the fan nut manufactured by the drawing method have.

In addition, it is possible to mass-produce the fan nuts at three positions in the width direction of the long steel sheet material and to continuously perform such operations while moving the steel sheet material along the longitudinal direction of the steel sheet material, And the productivity is improved. That is, the sequential transfer mold used in the forging press of the present invention is applied as one set, and when such a sequential transfer mold is used, the production speed can be adjusted upward, And it is effective to reduce the initial investment cost by self-transferring the steel sheet material, which is the base material of the fan nut.

In addition, since no fused protrusion is formed when forming the mold recess for the coupling with the material to be bonded, the fused material is joined to the fan nut, so that fine cracks do not occur due to the fused protrusion, There is no effect at all.

1 is a partial perspective view of a forging press used in a method of manufacturing a fan nut according to the present invention;
2 is a plan view of a steel sheet material as a base material in the method of manufacturing a fan nut according to the present invention.
3 is a schematic flowchart of a method of manufacturing a fan nut according to the present invention
4 is a perspective view of a fan nut manufactured by the manufacturing method of the fan nut according to the present invention,
5 is a longitudinal sectional view of a fan nut manufactured by the method of manufacturing a fan nut according to the present invention
Fig. 6 is a schematic view of forming a mold groove in a fan nut manufactured by the method of manufacturing a fan nut according to the present invention
7 is a longitudinal cross-sectional view of the coupling nut of the fan nut and the material to be bonded, which is manufactured by the manufacturing method of the fan nut according to the present invention

Hereinafter, preferred embodiments of a method of manufacturing a fan nut according to the present invention will be described in detail with reference to the accompanying drawings. It is to be understood that the present invention is not limited to the disclosed embodiments, but may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, It is provided to inform.

FIG. 1 is a perspective view of a part of a forging press used in the method of manufacturing a fan nut according to the present invention, and FIG. 2 is a plan view of a steel material as a base material in the method of manufacturing a fan nut according to the present invention.

1 and 2, a forging press P used in the method of manufacturing a fan nut according to the present invention includes a punch die 30 on which a long steel plate material 20, which is a base material of a fan nut, And a forging punch 40 provided on the upper portion of the punch die 30.

The steel plate material 20 has only a portion 50a which is to be a fan nut properly in the middle, upper and lower portions in the width direction, and the other portion has an incised shape. Thereby making it possible to manufacture the maximum number of fan nuts in one steel sheet material 20. [

The punch die 30 is formed in the form of a successive transfer mold for sequentially transferring the steel sheet material 20 on its upper surface. When the steel sheet material 20 is placed on the steel sheet material 20, The present invention is not limited to the above-described embodiments, and it is possible to easily manufacture other types of fan nuts by disposing the set mold as a set mold corresponding to the entire material 20 and mounting the set mold as a set mold for manufacturing other types of fan nuts . The predetermined portion 50b in the width direction of the punch die 30 becomes a portion that coincides with the portion 50a to be the fan nut of the steel plate material 20. [

The forging punch 40 is used for the initial drawing operation and the forging operation of the steel sheet material for manufacturing the pan nuts and can be replaced with various types of forging punches 30 in order to make the shape of the fan nuts have.

A method of manufacturing the fan nut of the present invention using the forged press constructed as described above will be described in detail as follows.

FIG. 3 shows a schematic flow chart of a method of manufacturing a fan nut according to the present invention.

3, according to the method of manufacturing a fan nut according to the present invention, first of all, at three portions in the width direction of the steel sheet material 20 on the punch die 30 used as a sequential feed metal mold, At the same time, the steel sheet material 10 is expanded in a roughly cap-like shape (drawing step) by a drawing operation by the drawing punch 40a.

Next, the body portion 1 and the flange portion 2 are sequentially formed in a primary shape and a secondary shape by a primary forging punch 40b in a cap shape roughly made of the steel plate material 20, A portion for forming a bolt hole is formed by the forging punch 40c (primary forging step).

Next, the shape of the fan nut roughly formed by the forging work is precisely machined to the design dimension by the cemented carbide tool, and the shaping work for luster is applied to the forging press by a shaping machine made of a cemented carbide tool, (The shaping step).

Next, though not shown in the region where the bolt hole with the shape of the fan nut is formed, the hole 60 is formed through the third forging punch (second forging step).

Next, the periphery of the lower end of the hole 60 penetrating the portion where the bolt hole is to be formed is trimmed by chamfering (chamfering step) by the third forging punch.

Next, a thread is formed in the hole 60 by a hole piercing operation to form a bolt hole 3 (hole piercing step).

Next, the flange portion 2 having the shape of a fan nut formed up to the bolt hole 3 is subjected to side notching (side notching step) in which a mold groove for forming a coupling member is formed by a press-fitting punch. The side notching step of forming the mold groove will be described later in detail.

Next, the manufacturing of the fan nuts is finally completed (trimming step) by trimming finishing the shape of the fan nuts completed until the side notching.

The manufacturing work of the fan nuts at one time in the width direction of the steel plate material 20 is performed continuously along the longitudinal direction while moving the steel plate material 20 on the punch die 30, ), A plurality of fan nuts are manufactured at once.

4 is a perspective view and an enlarged perspective view of a main portion of a fan nut manufactured by the method of manufacturing a fan nut according to the present invention and FIG. 5 is a longitudinal sectional view of a fan nut manufactured by the method of manufacturing a fan nut according to the present invention will be.

4 and 5, the fan nut 5 manufactured by the method of manufacturing a fan nut according to the present invention is basically composed of a cylindrical body 1 and a lower end of the body 1 And a nut hole 3 formed to extend inwardly from the central portion of the upper end surface of the body portion 1. The flange portion 2 has a flange portion 2, And a plurality of mold grooves 4a for forming a mold-contacting force with the material to be bonded are formed on the base 2 at predetermined intervals along the periphery. The mold recess 4a is formed from the flange portion 2 toward the body portion 1 so that the through hole H is formed between the flange portion 2 and the body portion 1 after the mold recess 4a is formed, Respectively.

As shown in Fig. 6, the flange portion 2 formed on the body portion 1 of the fan nut is directed upward so that the flange portion 2 formed on the body portion 1 of the fan nut faces upwards The press-fit punch 6 is press-fitted into the body 1 from the upper side of the flange portion 2 with a constant pressure input to form a plurality of the mold grooves 4a. At this time, 6 are formed in the flange portion 2 by suitably adjusting the press-in force of the press-fit punches 6, 6 so that the mold recesses 4a are formed in the flange portion 2, It is preferable that protrusions corresponding to the mold recesses 4a are not formed to be pushed outwardly of the body section 1.

The formation of the mold groove 4a by the press-fit punch 6 is performed by a method of belonging to a shearing force by a kind of press molding or by forming the mold groove 4a by a method similar to cutting when viewed by plastic working, It is necessary to minimize the shear force in order to prevent the protrusion corresponding to the mold groove 4a from being formed by the shearing force. For this purpose, a constant radius of curvature (for example, R). In order to reinforce the rigidity of the press-fit punch 6 by such a radius of curvature R, even if the shape of the press-in punch 6 is not given, the frictional surface of the press-fit punch 6 contacting the corner portion is minimized, . That is, a small protrusion may be formed on the outside of the body portion 1 corresponding to the mold groove 4a by the deformation in the direction of 'A' with respect to the shearing repulsion by the press-in of the press-in punch 6, As described above, it is preferable to form the mold groove 4a without forming a protrusion with which the entire side surface protrudes finely.

The mold recess 4a is formed with the minimum shearing force when the curvature radius R is equal to or larger than the thickness t of the fan nut 5 but the product shape is deformed by the shear force, It was confirmed through the production of continuous samples that no corresponding protrusion was formed. For example, when the thickness t of the fan nut 5 is 2t, the R value of the radius of curvature is preferably 2 or more. When the size of the mold groove 4a is 2 mm or more due to the shearing force of the press-in punch 6, the curvature of the boundary portion between the flange portion 2 and the body portion 1 from the outside of the body portion 1 The value of the radius R is 0.2 or less so that the shearing force can be minimized.

FIG. 7 is a longitudinal cross-sectional view of a coupling part of a fan nut manufactured by the method of manufacturing a fan nut according to the present invention.

7, when the fan nut 5 is inserted into the material to be bonded 10 and then placed on a press-fitting die and forcedly press-fitted into the flange portion 2 by the press-molding punch, The volume increase of the material to be bonded 10 generated at the same time as the press-fitting is transferred to the plurality of mold grooves 4a through the through holes H by the flow of the solid material, 10) are combined, it is possible to generate a clamping force, that is, a mold clamping force, and generate a rotation preventing force.

Since the molding force is normally generated by the plurality of mold grooves 4a as described above but the protrusion does not protrude to the outside of the body 1 of the fan nut 5, 5) and the material to be bonded does not occur at all due to a fine gap.

As described above, the method of manufacturing a fan nut according to the present invention has been described with reference to the drawings. However, the present invention is not limited to the embodiments and drawings disclosed in the present specification, Various modifications may be made by those skilled in the art.

1: body portion 2: flange portion
3: Bolt hole 4a, 4b: Mold joint
5: Fan nut 6: Indentation punch
10: bonding material 20: steel sheet material
30: punch die 40: forging punch
40a: drawing punch 40b: primary forging punch
40c: secondary forging punch 50a: part to be a pan nut of steel sheet material
50b: a predetermined portion in the width direction of the punch die
60: hole H: through hole
P: Forging Press

Claims (3)

1. A method of manufacturing a fan nut comprising a body portion, a flange portion, and a bolt hole,
A drawing step of drawing the middle, upper and lower portions along the width direction of the steel strip in a basic shape to be a fan nut, while continuously drawing three widthwise portions along the lengthwise direction;
The basic shape formed by the drawing is subjected to a rough forging operation successively along the longitudinal direction with one set of the middle, the upper and the lower three along the width direction of the steel sheet material by forging punches, A first forging step of forming a flange portion;
A shaping step of sequentially shaping the fan nut having the body and the flange portion to a design dimension and performing a shaping work for luster;
Performing a forging operation to form a bolt hole in the fan nut having completed the shaping operation;
A chamfering step of chamfering a bottom surface of the fan nut on which the bolt hole is formed by a forging punch;
A hole piercing step of forming a thread in the bolt hole;
A side notching step of forming a mold groove by a press-fit punch on a flange portion of the fan nut having completed the hole piercing; And
A trimming step of removing an unnecessary portion of the fan nut on which the mold recess is formed;
Wherein the first and second flanges are spaced apart from each other. The method according to claim 1,
Wherein the first forging step is performed by performing a plurality of steps of forging punches having various shapes so as to approximate the shapes of the body portion and the flange portion of the fan nuts in the shape of the basic fan nuts by the drawing step, ≪ / RTI > The method according to claim 1,
Characterized in that when forming the mold groove in the flange portion of the fan nut by the press-fitting punch in the side notching step, the mold protrusion is not formed on the opposite side of the mold groove while forming the through hole in the mold groove Gt;

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