KR101858526B1

KR101858526B1 - Manufacturing method for tool holder

Info

Publication number: KR101858526B1
Application number: KR1020170170301A
Authority: KR
Inventors: 김재춘
Original assignee: 주식회사 세광세록스
Priority date: 2017-12-12
Filing date: 2017-12-12
Publication date: 2018-06-28

Abstract

The present invention relates to a manufacturing method for a tool holder, which significantly improves manufacturing ease by forming a key groove prearrangement portion and a protrusion groove prearrangement portion in advance in a temporary forming tool holder in a process of manufacturing the temporary forming tool holder through a forge welding process. According to the present invention, the manufacturing method comprises the following steps of: arranging a second mold in a lower portion of a first mold, arranging a third mold in an upper portion of the first mold to form a forge welding space, and arranging a raw material in the forge welding space; manufacturing a temporary forming tool holder having a key groove prearrangement portion and a protrusion groove prearrangement portion by forge processing a raw material arranged in the forge space; and manufacturing a tool holder forming a key groove and a protrusion groove by cutting the key groove prearrangement portion and the protrusion groove prearrangement portion of the temporary forming tool holder.

Description

Technical Field [0001] The present invention relates to a method of manufacturing a tool holder,

The present invention relates to a method of manufacturing a tool holder, and more particularly, to a method of manufacturing a tool holder in which, in the process of manufacturing a provisional tool holder through forging, a key groove pre- To a method of manufacturing a tool holder.

In general, a machine tool is provided with a plurality of tools in a tool box, and a specific tool among the tools of the tool box is selected by a specific control command to perform a corresponding operation. At this time, Is called a tool holder.

Such a tool holder generally includes a rotating shaft that is coupled to the spindle and rotates, includes a body for providing a base, and includes engagement and retention means for supporting engagement with the spindle. And a holder key and a key groove for accommodating the holder key.

[0002] There is a conventional technology relating to a tool holder, which is disclosed in Japanese Patent Registration No. 10-1498605 (Feb. 26, 2015) (prior art). In the prior art, a tool holder is provided with a mounting groove and a bite, a clamping bolt, The holder is fixed to the machine tool.

However, conventional techniques including the prior art do not provide any technology related to a method of manufacturing a tool holder that can remarkably improve ease of manufacture of a tool holder.

SUMMARY OF THE INVENTION The present invention has been conceived in order to solve the above-mentioned problems, and it is an object of the present invention to provide a method of manufacturing a pseudo-type tool holder by forging a keyway preform and a pre- And it is an object of the present invention to provide a method of manufacturing a tool holder in which the cutting process for forming the keyway and the engaging groove is remarkably shortened by completing the tool holder by cutting the planned portion.

The present invention having the above objects has the following steps and features.

A second mold having a lower molding part corresponding to a lower shape of the tool holder, and a third mold having an upper molding part corresponding to an upper shape of the tool holder, A method of manufacturing a tool holder using a mold,

Disposing the second metal mold at a lower portion of the first metal mold, disposing the third metal mold at an upper portion of the first metal mold to form a forging space, placing the raw material in the forging space, A step of forging the disposed raw material to produce a provisional tool holder having a key groove preliminary portion and an engagement groove preliminary portion and cutting the key groove preliminary portion and the preliminary groove preliminary portion of the provisional tool holder to form a key groove and an engagement groove And manufacturing the tool holder.

In addition, the lower molding part of the second metal mold may be provided so as to protrude upward and be disposed in the side molding part of the first metal mold, and the upper molding part of the third metal mold may be recessed upward.

In addition, the predetermined key groove portion may be formed by a first key groove forming portion protruding upward from the lower forming portion of the second mold or a second key groove forming portion protruding downward from the upper forming portion of the third mold. .

Further, the engaging groove predetermining portion includes a first engaging groove forming portion protruding toward the center side in the side forming portion of the first mold, a second engaging groove forming portion protruding upward from the lower forming portion of the second metal mold, And a third engaging groove forming part protruding downward from the upper forming part of the third mold.

According to the present invention having the steps and features described above, since the provision of the key groove portion and the engaging groove portion in the provisional tool holder manufactured through the forging process significantly shortens the cutting process for forming the key groove and the engaging groove, It is possible to remarkably improve the manufacturability such as shortening of production cost, reduction of labor and the like.

1 is a block diagram showing each step of the present invention;
2 is a perspective view showing a mold structure according to the present invention.
3 is a plan view showing a mold structure according to the present invention.
Fig. 4 shows an embodiment of a provisional tool holder and a completed tool holder manufactured by the present invention. Fig.
5 to 7 illustrate an embodiment of a tool holder produced by the present invention.
5 is a perspective view of a tool holder manufactured by the present invention;
6 is a rear view of the tool holder produced by the present invention.
7 is a detailed view of a tool holder manufactured by the present invention;

While the present invention has been described in connection with certain embodiments, it is obvious that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention. It is to be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but on the contrary, is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the term " comprising " or " consisting of ", or the like, refers to the presence of a feature, a number, a step, an operation, an element, a component, But do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

It is to be understood that the first to second aspects described in the present specification are merely referred to in order to distinguish between different components and are not limited to the order in which they are manufactured, It may not match.

Prior to describing the present invention, a definition of a rough direction will be given. In general, the tool holder H has a cylinder-like shape and its cross-section has a circular-like shape. However, in the description of the present invention, the direction of the upper, Right, left, and right, and correspondingly, the tool holder H has upper, lower, left, and right sides. Unless otherwise specified, the claims shall also be followed.

The present invention relates to a method of manufacturing a tool holder in which manufacturing easiness is remarkably improved by preliminarily forming a key groove preliminary portion and an engagement groove preliminary portion in a provisional-type tool holder in the process of manufacturing a provisional-type tool holder through forging.

Hereinafter, a method of manufacturing a tool holder according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram showing each step of the present invention.

As shown in Fig. 1, the method includes a mold placing step S1, a forging step S2, and a cutting step S3.

Before explaining the present invention in detail, a mold structure for practicing the present invention will be described with reference to FIG. 2 (perspective view) and FIG. 3 (top view) showing a mold structure according to the present invention.

2 and 3, the molds used in the present invention largely include first through third molds M1, M2, and M3, and the first mold M1 includes a tool holder H And the second mold M2 has a lower molding portion 2m corresponding to the lower shape of the tool holder H and the third mold M3 Has an upper forming portion 3m corresponding to the upper shape of the tool holder H.

More specifically, the first mold M1 includes a mold body and a side mold portion 1m, and the side mold portion 1m is provided at the center of the mold main body. Particularly, (Or holes) formed at the center thereof.

Next, the second mold M2 includes the mold body and the lower molding portion 2m, and the lower molding portion 2m is provided at the center of the mold body. Particularly, the lower molding portion 2m is provided at the center of the mold body And is projected upward.

Next, the third mold M3 includes a mold body and an upper molding portion 3m, and the upper molding portion 3m is provided at the center of the mold body. Especially, the upper molding portion 3m is provided at the center of the mold body As shown in FIG. In the above description, the 'recessed shape' means that the depressed position is directed toward the upper side with respect to the direction in which the metal mold is coupled with the metal mold body. Reference)

The molds according to the present invention having the above structure are arranged such that the first mold M1 is arranged in a line, the second mold M2 is arranged below the first mold M1, Three molds M3 are arranged. At this time, the lower molding portion 2m of the second mold M2 is disposed in the side molding portion 1m of the first mold M1 because the upper molding portion 2m protrudes upward.

The molds arranged as described above generate a forging space which is a space surrounded by the side forming part 1m, the lower forming part 2m and the upper forming part 3m, the raw material Hr is disposed in the forging space, (Hr) becomes a temporary tool holder (Hm) through forging.

1 to 3, each step of the present invention will be described in detail. First, the mold placing step S1 is a step for forming the temporary tool holder Hm by forging the raw material Hr, In a step of properly arranging the molds, a second mold M2 is disposed at a lower portion of the first mold M1, a third mold M3 is disposed at an upper portion of the first mold M1, , And arranging the raw material (Hr) in the forging space.

In the mold placing step S1, a preferred embodiment is characterized in that the second mold M2 is disposed below the first mold M1, the material Hr is placed in the forging space, (M3) covers the upper portion of the first mold (M1).

Further, in the mold placing step S1, the raw material Hr may be plasticized by heating before being placed in the forging space, or may be placed in the forging space and then plasticized by heating . The concrete implementation of the plasticization of the raw material (Hr) will be referred to a well-known technique or to follow the common sense of ordinary skill in the art.

Next, the forging step S2 is a step for manufacturing the provisional tool holder Hm by forging the disposed raw material Hr, i.e., forging the raw material Hr disposed in the forged space, Is a step of manufacturing a provisional tool holder (Hm) having a portion (3 ') and a stopping portion (4').

Forging for the raw material Hr in the forging step S2 may be repeatedly performed through the third mold M3 or may be carried out by hitting the third mold M3 with separate hitting means . Such forging is a well-known technique, and for more specific forging, reference is made to conventional techniques and common sense of ordinary skill in the art.

The characteristic feature is that the provisional tool holder Hm manufactured in the forging step S2 has the key groove fixing portion 3 'and the locking groove fixing portion 4' The engaging groove forming part 4m has a key groove forming part 31m and 32m and a locking groove forming part 41m and 42m which are previously provided at positions where the key groove 3 and the engaging groove 4 are to be formed, ) 43m (see Fig. 4).

Next, the cutting processing step S3 is a step of cutting the provisional tool holder Hm to manufacture the tool holder H, and in this step S3, cutting processing equipment for the provisional tool holder Hm The key groove portion 3 'and the engaging groove portion 4' of the provisional tool holder Hm are cut to form the key groove 3 and the engaging groove 4, (See Fig. 4).

In the present invention including the above steps, the provisional tool holder Hm manufactured through the forging of the raw material Hr is provided with the key holding portion 3 'and the lock groove holding portion 4' in advance The cutting process for forming the key groove 3 and the engaging groove 4 can be drastically shortened and the manufacturing easiness such as the shortening of the manufacturing time and the labor saving can be drastically improved.

Fig. 4 is an embodiment showing the provisional tool holder Hm and the completed tool holder H manufactured by the present method.

Hereinafter, more detailed features and additional features of the present invention will be described with reference to FIGS. 1 to 3 and 4. FIG.

The present invention is characterized in that the key groove forming part 3 'is formed in the first key groove forming part 31m or the upper forming part 31m of the third mold M3, which protrudes upward from the lower forming part 2m of the second mold M2 And a second key groove forming part 32m protruded downward from the first key groove forming part 32m.

2 to 4, the first key groove forming part 31m protrudes upward from the lower forming part 2m of the second mold M2 and has a shape corresponding to the shape of the key groove 3 Respectively. Thus, in the forging step S2, the provisional tool holder Hm is provided with the key groove forming part 3 'at the lower part by the first key groove forming part 31m.

The second key groove forming part 32m protrudes downward from the upper forming part 3m of the third mold M3 and has a shape corresponding to the key groove 3. [ Thus, in the forging step S2, the provisional tool holder Hm is provided with the key groove portion 3 'at the upper portion by the second key groove forming portion 32m.

The first key groove forming portion 31m and the second key groove forming portion 32m may be independently or integrally formed. In the case of forming the key groove 3 in the lower portion of the tool holder H, Only a first key groove forming part 31m and only a second key groove forming part 32m when the key groove 3 is to be formed on the upper side of the tool holder H, The first key groove forming part 31m and the second key groove forming part 32m may be provided. FIGS. 2 to 4 show an embodiment having one keyway through one keyway forming part.

In Fig. 4A, it can be seen that the provisional tool holder Hm is provided with the key groove portion 3 'by the first key groove forming portion 31m or the second key groove forming portion 32m, It can be confirmed that the tool holder H having the key groove 3 as shown in FIG. 4B can be manufactured through the cutting step S3 of the provisional tool holder Hm.

Next, in this method, the retaining groove assuming portion 4 'includes a first engaging groove forming portion 41m and a second engaging groove forming portion 41m protruding from the side forming portion 1m of the first mold M1 toward the center, A second engaging groove forming part 42m protruded upward from the lower forming part 2m of the third mold M3 and a third engaging groove forming part 42m protruding downward from the upper forming part 3m of the third mold M3 43m, respectively.

2 to 4, the first engaging groove forming part 41m protrudes toward the center side in the side forming part 1m of the first mold M1, and corresponds to the side part of the engaging groove 4 . The provisional mold tool holder Hm manufactured in the forging step S2 is provided with a side portion of the engaging groove preform 4 'by the first engaging groove forming portion 41m.

The second engaging groove forming part 42m protrudes upward from the lower forming part 2m of the second mold M2 and has a shape corresponding to the lower part of the engaging groove 4. [ The provisionally formed tool holder Hm manufactured in the forging step S2 is provided with a lower portion of the retaining groove preliminary portion 4 'by the second retaining groove forming portion 42m.

The third engaging groove forming part 43m protrudes downward from the upper forming part 3m of the third mold M3 and has a shape corresponding to the upper part of the engaging groove 4. [ The provisional tool holder Hm manufactured in the forging step S2 is provided with an upper portion of the engaging groove portion 4 'by the third engaging groove forming portion 43m. That is, the provisional tool holder Hm has the engaging groove forming portion 4 'by the first to third engaging groove forming portions 41m, 42m, 43m.

In FIG. 4A, it can be seen that the provisional tool holder Hm is provided with the engaging groove preliminaries 4 'by the first to third engaging groove forming portions 41m, 42m and 43m , It can be confirmed that the tool holder H having the engaging groove 4 as shown in FIG. 4B can be manufactured through the cutting step S3 of the provisional tool holder Hm .

Fig. 5 is a perspective view of a tool holder (hereinafter referred to as " H ") manufactured by the present invention, Fig. 6 is a perspective view of the apparatus H, Fig. 7 is a detailed view of the present apparatus H. Fig. Hereinafter, each sub-feature of the tool holder H manufactured by the method will be described with reference to FIGS. 5 to 7. FIG.

(Hereinafter, a direction specific criterion different from the description of the present method will be applied, and the upper, lower, left, and right sides will be distinguished based on FIG. 5).

As shown in Fig. 5, the apparatus H mainly includes a pivot shaft 1, a body 2, and a key groove 3.

For each configuration, the rotary shaft 1 is coupled to the spindle at the center of rotation so that the device H can be rotated by receiving a rotational force from the spindle. Here, the spindle is a part of a machine tool such as a lathe, a drilling machine, or the like, and is a rotary shaft used for mounting a tool holder such as the present invention.

Next, the body 2 is provided with a base of the apparatus H, and as shown in Fig. 5, a coupling portion 21 with the rotary shaft 1 is provided on one side, And a mounting portion 22. Here, with reference to Fig. 5, one side is the upper side and the other side is the lower side. The coupling portion 21 is coupled to the rotary shaft 1. The coupling between the rotary shaft 1 and the body 2 is preferably integrally coupled through a welding connection. The tool mounting portion 22 is provided with a drill, a cutter, A tool suitable for the operation such as a cutting tool is selected and combined.

5 to 7, the key groove 3 is provided to receive the holder key provided on the spindle for supporting the coupling between the apparatus H and the spindle. .

Particularly, the key groove 3 is a key feature of the present invention. As shown in FIGS. 5 to 7, the key groove 3 includes a seating part 31 provided at a position recessed from the outer surface of the body 2, An opening 32 provided at one side and a wall portion 33 provided at a position excluding the opening 32 along the periphery of the seating portion 31.

The opening portion 32 is a space opened to one side of the seating portion 31 and the wall portion 33 is a space in which the key groove 3 is seated, This is a part that can be fixed.

The present apparatus having the above-described features and features can afford a margin for tolerance by presenting a key groove 3 of the form that one side is opened through the opening 32, thereby providing improved workability and furthermore, Cost reduction effect.

In an additional feature of the apparatus, the body 2 can be composed of a first body 2A on one side and a second body 2B on the other side coupled thereto, and in particular, the first body 2A And the second body 2B is arranged on the lower side on the upper side.

The engaging portion 21 may be provided on the first body 2A and the tool mounting portion 22 may be provided on the second body 2B. More preferably, 1, the tool mounting portion 22 may be provided at the other end (lower end) of the second body 2B at one end (upper end) of the body 2A.

Also, it is preferable that the first body 2A and the second body 2B are integrally coupled to each other.

In the present invention, the engaging portion 21 to which the rotational force is applied and the tool mounting portion 22 to which the tool is mounted are physically separated from each other by the separation structure of the body 2, It is possible to minimize the problem that the tool is released by the tool.

5 to 7, the apparatus H includes a seat portion 31 of the key groove 3, and a seat portion 3 of the key groove 3, which is a part of the key groove 3, And can be formed in a U-shape.

In this embodiment, the 'U' shape originates from the shape of the opening 32 and the wall portion 33. In one embodiment, in the U shape, the curved portion of the wall portion 33 is formed on the rotation axis 1) direction, the opening 32 can be arranged in the direction of the tool mounting portion 22.

With this configuration, the present invention can have a margin for tolerance and a positive sensitivity of the holder key, the curved portion of the wall portion 33 providing a margin for tolerance, The holder key itself is moved along the curved portion of the wall portion 33 so as to be accommodated while correcting the correct position, thereby providing improved manufacturing and use convenience .

Next, another detailed feature of the key groove 3 is that the wall portion 33 of the key groove 3 is inclined with respect to the inclined surface 330 so that the width of the seating portion 31 widens toward the upper side And the like.

7, the wall portion 33 includes an inclined surface 330 on the inner side, and the inclined surface 330 is formed such that the width of the seating portion 31 increases toward the upper side.

The inclination of the inclined surface 330 works together with the above features to further enhance the effect of ensuring clearance for the tolerance and relieving the positive sensitivity of the holder key.

Particularly, the angle (a) formed by the inclination angle a of the inclined plane 330, that is, the extension line of the vertical line of the wall portion 33 and the inclined plane 330 is preferably 5 to 15 degrees, more preferably 10 degrees.

The clearance between the holder key and the wall portion 33 is significantly increased so that the holder key is not moved to the seating portion 31. In this case, So that the effect of supporting the coupling force is deteriorated.

Next, in further detail of another key groove 3, the apparatus H includes a first round 331 having a wall portion 33 of the key groove 3 at its inner end, 2 < / RTI >

7, the first round 331 is provided at the inner end of the wall portion 33, that is, at the lower end of the wall portion 33 (the seating surface side of the seating portion 31) And the second round 332 is provided at the outer end of the wall portion 33, that is, at the upper end of the wall portion 33 (the outer surface side of the body 2).

The first round 331 and the second round 332 also provide an effect of reducing the sensitivity of the holder key to the correct insertion of the holder key. And the second round 332 provided on the outer side corrects the correct position of the holder key that enters the seating part 31. In this case,

The apparatus H may further include a latching groove 4 provided on the outer surface of the body 1 and provided around the other portion where the key groove 3 is not provided.

The latching groove 4 has an effect that the attachment of the body 1 is held more firmly, and further, the body 1 is prevented from being shaken.

The present invention is further characterized in that it can further include a corrosion preventing layer provided on the outer surface of the pivot shaft (1) and the body (2).

The anti-corrosive layer is composed of a mixture of 100 parts by weight of silica filler and water, 2 to 3 parts by weight of pozzolan, 3 to 4 parts by weight of wax or paraffin, 1 to 2 parts by weight of styrene thermoplastic elastomer, And 1.5 to 3 parts by weight of an amorphous polyolefin (APO). Preferably, the composition may be applied by applying a cushioning agent including the compositions and curing.

For each constitution, first, the mixed material is made by mixing silica filler and water, and it is possible to increase or decrease the specific gravity of water according to the production design such as coagulation and application of the cushioning agent.

In particular, the silica filler is added to improve the physical properties such as tensile strength and hardness, and the silica filler can use fumed silica having a relatively low incidence of yellowing phenomenon, and one of hydrophobic dry silica and hydrophilic dry silica Or more can be used.

Pozzolan is a natural mineral material such as diatomite, which is used to purify foreign matter adhering to the outer surface coated with the anticorrosive agent by anion release, deodorization and antibacterial action. And serves to prevent cracks from occurring. If the amount of the pozzolan is less than 2 parts by weight, the cleaning effect is low. If the amount is more than 3 parts by weight, the binding force is decreased.

Next, the corrosion inhibiting layer may further contain 3 to 4 parts by weight of wax or paraffin. Since the wax or paraffin has a melting point of 40 to 60 캜, it acts to lower the production temperature of the anticorrosive agent, It is not volatilized after curing of the application surface, and the quality is not deteriorated. When the amount of the wax or paraffin is less than 3 parts by weight, the effect of addition is scarcely added. When the amount of the wax or paraffin is more than 4 parts by weight, the brittleness of the anticorrosive coating increases and cracks occur easily.

Next, the corrosion inhibiting layer may further contain 1 to 2 parts by weight of a styrene thermoplastic elastomer. The styrene thermoplastic elastomer has a polystyrene block as a hard segment and a polybutadiene as a soft segment in the middle, (soft segment) structure. It can be low viscosity when dissolved in mixed solvent. It has excellent elasticity and low temperature durability, so cracks on the applied surface of the anticorrosive material due to the lapse of time and the low temperature durability of the anti- The synthetic zeolite powder dispersed in the particulate state has an advantage that the surface of the anticorrosive agent can have a certain buffer against the external force due to regular fine pores inside.

If the content of the amine-based curing agent is less than 2.5 parts by weight, the strength and durability may be lowered, which may cause deterioration of physical properties. If the content of the amine-based curing agent exceeds 3.5 parts by weight The viscosity becomes high and the workability becomes poor.

The anti-corrosion layer may further include 1.5 to 3 parts by weight of an amorphous polyolefin. Amorphous polyolefin (APO) is a strong adhesive material in which olefins such as ethylene and propylene are added and polymerized. The conductivity of the heat transferred to the inside is lowered to minimize the change in temperature acting on the surface of the anticorrosive material.

Hereinafter, one embodiment for explaining the effect of the corrosion prevention layer will be described.

Example

500 g of the silica filler and 430 g of water were mixed to prepare 930 g of a mixed material. 10 kg of pozzolan, 20 g of paraffin, 10 g of styrene plastic elastomer, 15 g of an amine-based curing agent and 15 g of amorphous polyolefin were mixed to prepare a first method.

After that, the anticorrosive agent is applied to the outer surface of the tool holder H prepared for testing. After the corrosion-preventing layer was formed through the step of completely curing, water was sprayed onto the surface of the tool holder H for 12 hours, and then the corrosion inhibition layer was removed to examine the degree of internal infiltration. As a result, no moisture was detected .

Although the description of the specific implementation of the method corresponding to the additional features of the present apparatus described above is omitted, it is expected that it will be reasonable for an ordinary technician to speculate and carry out through the description of the present apparatus, The detailed description of the mold of the present invention will be replaced with the description of the present apparatus.

In addition, the present invention described with reference to the accompanying drawings can be variously modified and changed by a person skilled in the art, and such modifications and changes should be construed as falling within the scope of the present invention.

M1: First mold 1m: Side molding part
M2: second mold 2m: lower molding part
M3: Third mold 3m: Upper forming part
31m: first key groove forming part 32m: second key groove forming part
41m: first engaging groove forming part 42m: second engaging groove forming part
43m: third engaging groove forming part
Hm: Pseudo-type tool holder
3`: Key groove example 4`:
H: Tool holder (this unit)
1: Pivot shaft 2: Body
3: keyway 4: latching groove

Claims

A second mold having a lower molding part corresponding to a lower shape of the tool holder, and a third mold having an upper molding part corresponding to an upper shape of the tool holder, A method of manufacturing a tool holder using a mold,
Disposing the second metal mold on the lower part of the first metal mold, disposing the third metal mold on the first metal mold to form a forging space, and placing the raw material in the forging space;
Forging the raw material disposed in the forging space to produce a provisional toolholder having a keyway preliminary portion and an engaging groove preliminary portion; And
Forming a key groove and an engaging groove in the provisional tool holder to form a key groove and an engaging groove, thereby manufacturing a tool holder;
Lt; / RTI >
Wherein the lower molding portion of the second mold is projected upward and is disposed in the side molding portion of the first mold,
Wherein the upper molding part of the third mold is provided in a shape recessed upward,
Further comprising the step of providing an anti-corrosion layer on the outer surface of the pivot shaft and the body of the tool holder manufactured through the steps,
The corrosion-
A mixture of 100 parts by weight of silica filler and water, 2 to 3 parts by weight of Pozzolan, 3 to 4 parts by weight of wax or paraffin, 1 to 2 parts by weight of a styrene thermoplastic elastomer, 2.5 to 3.5 parts by weight of an amine curing agent, And 1.5 to 3 parts by weight of amorphous polyolefin (APO).

The method according to claim 1,
Wherein the keyway includes a seating part provided at a position recessed from an outer surface of the body, an opening part provided at one side of the seating part, and a wall part provided at a position except the opening part along the periphery of the seating part,
Wherein the wall portion includes an inclined surface on the inner side surface, the width of the seating portion becoming wider toward the upper side,
The inclination angle of the inclined surface is 5 to 15 degrees,
Wherein the wall portion further comprises a first round at an inner end and a second round at an outer end.

The method according to claim 1,
The key-
A first key groove forming part protruding upward from the lower forming part of the second mold or a second key groove forming part protruding downward from the upper forming part of the third mold. Way.

The method according to claim 1,
The catching-
A first engaging groove forming part protruding toward the center side in the side forming part of the first metal mold, a second engaging groove forming part protruding upward from the lower forming part of the second metal mold, And a third engaging groove forming part protruding downward from the first engaging groove forming part.