KR102156262B1 - Coating apparatus for forming a diamond coating layer having uniform thickness on cutting tools - Google Patents

Abstract

The present invention relates to a coating apparatus for forming a diamond coating layer having a uniform thickness on surfaces of cutting tools, which includes: a cutting tool mounting part arranging a plurality of cutting tools on an upper portion on a straight line to mount the same thereon; a plurality of heating filaments arranged on front and back surfaces of the plurality of cutting tools in parallel with each other along a longitudinal direction of the cutting tools; and a cutting tool rotating part coupled to a lower portion of the cutting tool mounting part to integrally rotate the plurality of rotating tools at a predetermined angle.

Description

Coating apparatus for forming a diamond coating layer having uniform thickness on cutting tools}

The present invention relates to a device for coating diamond on the surface of a cutting tool to cut a workpiece having high strength and hardness, such as a carbon fiber composite, and more particularly, to form a diamond coating layer with a uniform thickness on the surface of the cutting tool. It relates to a coating device.

Carbon fiber composites are widely used in aviation and automobile fields because carbon fiber is used as a reinforcing material and resin, ceramic, metal, etc. are used as a base material. In order to process a carbon fiber composite material having such high strength and hardness, a cutting tool coated with a diamond on the tool surface is used so that the tool is not easily worn by friction during cutting.

To coat diamond on the tool surface, chemicals converted to plasma or thermal energy by various power sources (direct current, alternating current, high frequency, microwave) in a mixed gas atmosphere containing hydrocarbons such as methane (CH ₄ ) or benzene (C ₆ H ₆ ). It is formed by chemical vapor deposition (CVD) method, and the types include hot filament method, combustion method, DC discharge plasma method, arc discharge plasma jet, microwave plasma, and among them, thermal filament method is generally used. have.

In the hot filament method, a filament made of tungsten is placed in a chamber, and when electricity is applied through an electrode connected to the filament to heat the filament with resistance to a high temperature of 2,000°C, the mixed gas introduced into the chamber reacts and a tool placed near the filament. Diamond is coated. In such a coating by the hot filament method, the film formation speed and thickness of the tool surface are different depending on the distance between the filament and the tool, but the thickness of the thin film near the filament is formed thick, and the thickness of the thin film at the distant part is formed thin. There is.

In order to solve this problem, a coating device of Patent Publication No. 10-2016-0044082 was proposed. The above patented invention is a shaft connecting tools arranged in a row around a filament, a motor driving the shaft, and a connection between the shaft and the motor. As a result, it is proposed a method of converting the rotational motion of the motor into a linear motion to form a link part, and coating the diamond with a uniform thickness on the tool surface by rotating the shaft around the heated filament during coating.

However, such a method requires a large number of parts such as a motor and a link part, so that the structure is complex, and when the rotation is driven, an impact occurs due to the gear coupling of the shaft and the link part, and when the number or weight of tools increases, the load is affected. There is a possibility that the shaft may be bent, so there is a limit to stable coating work.

Korean Patent Publication No. 10-2016-0044082 (Name of invention: diamond coating cutting tool, diamond coating method of cutting tool, and coating device used in this coating method)

Accordingly, the present invention was devised to solve the problems of the conventional diamond coating apparatus, and provides a coating apparatus that can be stably driven by having a simple structure to form a diamond coating layer with a uniform thickness on the surface of a cutting tool. It has its purpose.

In order to solve the above technical problem, the present invention is a device for coating diamond on the surface of a cutting tool by injecting a mixed gas into the chamber, and a cutting tool seating part arranged and seated on the upper part of a plurality of cutting tools in a straight line. And, a plurality of heating filaments arranged side by side along the longitudinal direction of the cutting tool at the front and rear of the plurality of cutting tools, and a cutting tool that is coupled to the lower part of the cutting tool seat to integrally rotate the plurality of cutting tools at a predetermined angle. It has a rotating part.

Here, the cutting tool rotation unit rotates a plurality of cutting tools in one direction and then rotates again in the other direction to return to the original position.The cutting tool can be rotated and returned by a cycle set according to the temperature of the heating filament. have.

In addition, the cutting tool rotation unit can rotate and return the cutting tool by reciprocating linear motion of forward and backward according to the arrangement direction of the plurality of cutting tools, and the plurality of cutting tools can be integrally rotated by 90°.

In addition, the cutting tool rotation unit may pass through a plurality of tool holder fittings coupled to a lower portion of the cutting tool seating portion to define a fitting alignment plate arranged in a straight line, and a plurality of tool holder fittings protruding from the fitting alignment plate. It has a rotation driving unit that rotates integrally at an angle.

At this time, the tool holder coupling hole has a coupling protrusion coupled to the lower end of the tool holder in which the cutting tool is accommodated, and the lower portion protrudes from the coupling hole alignment plate, and the coupling hole is aligned through a carbon bushing to facilitate rotation. It is pierced through the plate and joined. In addition, a snap ring is coupled to an upper portion of the tool holder coupling hole so that the carbon bushing does not come off.

In addition, the rotation drive unit is provided in a linear direction of the rack gear that moves in a linear direction along the arrangement direction of a plurality of tool holder fittings by a driving cylinder, and a tool that rotates by being combined with the linear moving rack gear and is provided under the tool holder fitting. It is equipped with a pinion gear for rotation.

Here, the linear movable rack gear may be coupled to a plurality of rotation pinion gears for tool rotation provided in each of the lower portions of the plurality of tool holder fittings to integrally rotate the plurality of tool holder fittings.

In this case, the linear movable rack gear may be interposed between adjacent rows of the tool holder coupler formed in a plurality of rows.

According to the present invention, a plurality of cutting tools arranged between heating filaments arranged in a plurality of rows in a chamber in a mixed gas atmosphere are rotated integrally in one direction to reduce the temperature deviation of the surface of the cutting tool heated by the heating filament. During vapor deposition, a diamond coating layer can be formed with a uniform thickness on the surface of the cutting tool.

1 is a front view of a coating apparatus according to the present invention.
2 is a front view showing a plurality of cutting tools arranged between a plurality of rows of heating filaments according to the present invention.
3 is a plan view of FIG. 2.
Figure 4 is a perspective view of a combination of a plurality of cutting tools and cutting tool rotation according to the present invention.
5 is a cross-sectional view of FIG. 4.
6 is an exploded perspective view of a cutting tool and a rotating part of the cutting tool according to the present invention.
7 is an exploded perspective view of a rotating part of a cutting tool according to the present invention.
8 is a view showing the operation of the cutting tool rotated and returned according to the cutting tool rotation unit according to the present invention.
9 is a SEM photograph showing a comparison of the diamond coating layer formed on the surface of the cutting tool according to the Example and Comparative Example of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

This embodiment is provided to more completely describe the present invention to those with average knowledge in the art, and the shape of the element, the size of the element, the spacing between the elements, etc. in the drawings emphasize a more clear description. For this reason, it can be exaggerated or reduced.

In addition, in describing the embodiment, if a component is described as "formed", "included", "coupled", or "fixed" to another component, it is formed directly on the other component, It may be included, combined, or fixed, but it should be understood that other components may exist in the middle.

In addition, when it is determined that the technical features of the present invention may be unnecessarily obscure as matters already obvious to those skilled in the art, such as known functions or known configurations related in principle in describing the embodiments, the detailed The explanation will be omitted.

1 is a front view of a coating apparatus according to the present invention, FIG. 2 is a front view showing a plurality of cutting tools 11 disposed between a plurality of rows of heating filaments 30, and FIG. 3 is a plan view of FIG. 2.

Referring to Figures 1 to 3, the coating apparatus according to the present invention includes a chamber 10 having an inner space formed therein, a cutting tool seating portion 20 provided in the chamber 10 to seat the cutting tool 11 thereon, A heating filament 30 for heating the cutting tool 11 seated on the cutting tool seat 20, and a cutting tool rotating unit that is coupled to the lower portion of the cutting tool seat 20 to rotate the plurality of cutting tools 11 It is made including 40.

The chamber 10 has an enclosed inner space in which the coating of the cutting tool 11 is formed, and an injection port for injecting a mixed gas of methane (CH ₄ ) and hydrogen (H ₂ ) for diamond coating on one side, and the other side After diamond coating is completed, an outlet for discharging gas is formed. A gas supply unit 50 is provided on the inner upper part of the chamber 10 to inject the mixed gas injected into the chamber 10 into the cutting tool seating unit 20 by being connected to the injection port.

The cutting tool seating portion 20 is arranged at the lower end of the gas supply unit 50 by seating a plurality of cutting tools 11 at the top, and a tool holder 21 that is accommodated and coupled to the lower end of the cutting tool 11, a plurality of The tool holder 21 of the mounting plate 22 is coupled to the surface, and a transfer roller is provided in the lower portion of the mounting plate 22 to enter the chamber 10. A plurality of tool holders 21 are coupled to the surface of the mounting plate 22 in a grid form, and the lower end of the cutting tool 11 is coupled to the open upper surface of the tool holder 21. Accordingly, a plurality of cutting tools 11 are arranged on a straight line at regular intervals on the upper part of the cutting tool seat 20.

As shown in the drawing, a plurality of heating filaments 30 are arranged in the longitudinal direction of the cutting tool along the width direction inside the chamber 10, and are arranged in a plurality of rows parallel to the front and rear surfaces of the plurality of cutting tools 11 As a result, the cutting tool 11 is heated from both sides. The heating filament 30 is formed of a heating material such as tungsten that is electrically connected to an external power source and can generate heat by resistance heat. The heating filament 30 generates resistance heat of approximately 1,800 to 2,200°C by the applied power. To be heated.

The heating filaments 30 are preferably arranged at equal intervals along the longitudinal direction of the cutting tool 11, in this way, the heating filaments 30 are along the longitudinal direction in both directions of the front and rear surfaces of the cutting tool 11 As it is arranged at equal intervals, it is possible to reduce the temperature deviation between the surfaces of the coated cutting tool 21, so that coating with a uniform thickness is possible, and also the internal temperature of the coating space can be made to be high, thereby improving the film formation speed. have.

4 is a perspective view of a combination of a plurality of cutting tools 11 and a cutting tool rotating part 40 according to the present invention, FIG. 5 is a cross-sectional view of FIG. 4, and FIG. 6 is a cutting tool 11 and a cutting tool rotating part 40 It is an exploded perspective view of, and Figure 7 is an exploded perspective view of the cutting tool rotating part 40.

4 to 7, the cutting tool rotation part 40 is coupled to the lower part of the cutting tool seating part 20 to integrally rotate the plurality of cutting tools 11 at a predetermined angle, and a plurality of tool holders 21 The tool holder coupling part 41 coupled to the lower portion of the coupling member alignment plate 42 arranged in a straight line, and a plurality of tool holder coupling holes 41 protruding from the coupling member alignment plate 42 at a predetermined angle. It has a rotation driving unit that rotates integrally.

The tool holder coupling part 41 is formed in a cylindrical shape, and the upper part is formed with a coupling protrusion 44 that is coupled to the coupling groove 43 formed at the lower end of the tool holder 21, and the lower part of the coupling hole alignment plate 42 It protrudes from the lower surface. The coupler alignment plate 42 is coupled to the lower portion of the cutting tool mounting portion 20 through a plurality of tool holder fittings 41 are coupled through, and the combined tool holder fittings 41 interposed therebetween. The carbon bushing 45 is coupled to the inner periphery of the mounting hole of the coupling hole alignment plate 42 to which the tool holder coupling portion 41 is coupled to facilitate rotation of the tool holder coupling portion 41 by a rotation driving unit. In addition, a snap ring 46 is coupled to an upper portion of the tool holder fitting 41 to which the carbon bushing 45 is coupled so that the carbon bushing 45 does not come off.

The rotary drive unit is a drive shaft 47 coupled by a drive cylinder 60, a linear rack gear 48 coupled to the drive shaft 47 and moving in a linear direction along the arrangement direction of a plurality of tool holder couplings 41, And a pinion gear 49 provided below the tool holder coupling part 41 and rotated by being coupled to the linear moving rack gear 48. Therefore, as the pinion gear 49 for tool rotation is engaged and rotated with the rack gear 48 that is linearly moved by the driving cylinder, the plurality of tool holder engaging ports 41 coupled to the pinion gear 49 also rotate. Thus, a plurality of tool holders 21 in which the cutting tool 11 is accommodated are integrally rotated. At this time, the linear movable rack gear 48 may be provided interposed between adjacent rows of the tool holder coupling part 41 formed in a plurality of rows.

As described above, the present invention can reduce the temperature deviation of the surface of the cutting tool heated by the heating filaments 30 disposed on the front and rear surfaces of the cutting tool 11 by rotating the cutting tool 11 in one direction. A diamond coating film can be formed with a uniform thickness.

In order to form a diamond coating film with a more uniform thickness, the rotation driving unit can rotate the cutting tool 11 in one direction and then rotate it in the other direction to return it to its original position as shown in FIG. 8. The rotation and return of (11) may be made by a cycle set according to the temperature of the heating filament (30). For example, when the heating filament 30 temperature is set higher, the rotation and return cycle is faster, and when the heating filament 30 temperature is relatively low, the rotation and return cycle is slower.

The rotation and return of the cutting tool 11 can be achieved by reciprocating linear motion of the forward and backward movement of the linear rack gear 48 as described above, and are arranged on the front and rear sides as shown in FIG. It is preferable to rotate the side of the cutting tool 11 located farthest from the heated filament 30 by 90° so that it is closest to the heating filament 30.

Examples and comparative examples of forming a diamond coating layer on the surface of a cutting tool using the coating apparatus according to the present invention made as described above will be described below.

<Example>

A 12-edged end mill is seated on the cutting tool seat 20, and the heating filaments 30 are placed at equal intervals along the longitudinal direction on the front and rear of the cutting edge, and then hydrogen gas and methane gas are injected into the chamber. I did. Then, by heating by applying a current to the heating filament 30, diamond coating of the end mill seated on the cutting tool seat 20 was performed. During the deposition time, the end mill was rotated at 90° and returned to rotation every 1 hour using the cutting tool rotating part 40.

<Comparative Example>

Unlike the example, a diamond coating layer was formed on the surface of the end mill under the same conditions without rotating the end mill.

<Diamond coating layer thickness comparison>

As shown in FIG. 9, in the embodiment, the thickness of the diamond coating layer deposited at the four points (①, ②, ③, ④) of the end mill closest to the heating filament 30 was measured when rotating at 90° and returning to rotation. , In the comparative example, the thickness of the diamond coating layer deposited at the two points (①, ③) of the end mill closest to the heating filament 30, which is the same position as the end mill of the Example, and the two points farthest (②, ④) were measured. . The thickness of the diamond coating layer was measured through SEM cross-sectional analysis as shown in FIG. 9, and the results are shown in Table 1 below.

① Branch ② Branch ③ Branch ④ Branch Example 6.3㎛ 6.6㎛ 6.4㎛ 6.3㎛ Comparative example 7.8㎛ 6.5㎛ 8.1㎛ 6.4㎛

As shown in Table 1 above, in the Example, the thickness deviation of the diamond coating layer deposited at the four points (①, ②, ③, and ④) of the end mill is only ±0.3㎛, whereas the thickness deviation of the diamond coating layer of the comparative example is ± It can be seen that there is a difference of more than 5 times compared to the Example in 1.7㎛.

Therefore, the present invention reduces the temperature deviation of the surface of the cutting tool heated by the heating filament by integrally rotating a plurality of cutting tools disposed between the heating filaments arranged in a plurality of rows on the front and rear sides of the chamber. During vapor deposition, a diamond coating layer can be formed with a uniform thickness on the surface of the cutting tool.

The present invention described above is not limited to the described embodiments, and it is apparent to those of ordinary skill in the art that various modifications and variations can be made without departing from the spirit and scope of the present invention. Therefore, such modifications or modifications will have to belong to the claims of the present invention.

10: chamber 11: cutting tool
20: cutting tool seat 21: tool holder
22: seat plate 30: heating filament
40: cutting tool rotating part 41: tool holder coupling
42: coupling hole alignment plate 43: coupling groove
44: coupling protrusion 45: carbon bushing
46: snap ring 47: drive shaft
48: linear moving rack gear 49: pinion gear for tool rotation
50: gas supply unit 60: drive cylinder

Claims (12)

In the device for coating diamond on the surface of a cutting tool by injecting a mixed gas into the chamber,
A cutting tool seating portion arranged and seated on a plurality of cutting tools in a straight line;
A plurality of heating filaments arranged side by side along the longitudinal direction of the cutting tool on the front and rear surfaces of the plurality of cutting tools; And,
Combined with the lower part of the cutting tool seating part, the plurality of cutting tools are integrally rotated in one direction by reciprocating linear motion of forward and backward at a cycle set according to the temperature of the heating filament, and then integrally rotated in the other direction to the original position. It includes; a cutting tool rotating part to return to,
The cutting tool rotating part,
A tool holder engaging hole having an engaging protrusion coupled to a lower end of the tool holder accommodating the cutting tool formed on an upper portion thereof and coupled to a lower portion of the cutting tool seating portion,
A coupler alignment plate arranged in a straight line by protruding lower portions of the plurality of tool holder fittings through a carbon bushing; And,
And a rotation driving unit that integrally rotates a plurality of the tool holder coupling holes to which a snap ring is coupled to an upper portion so that the carbon bushing does not come off at a predetermined angle, and
The rotation driving part,
A linear movable rack gear provided between neighboring rows of the tool holder fittings formed in a plurality of rows and moving in a linear direction along the arrangement direction of the plurality of tool holder fittings by a driving cylinder; And,
A coating apparatus comprising: a pinion gear for rotation of a tool provided under the tool holder coupling unit and coupled with the linear moving rack gear to rotate. delete delete delete delete delete delete delete delete delete delete delete

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