KR101467084B1 - Apparatus for Cooling Machining Tool Using Nitrogen Gas and Method of Cooling Machining Tool Using Nitrogen Gas - Google Patents

Abstract

The present invention relates to a tool cooling apparatus using nitrogen gas and a tool cooling method using nitrogen gas. More particularly, the present invention relates to a tool for cooling a workpiece and a tool using a nitrogen gas A cooling device, and a tool cooling method using nitrogen gas.
INDUSTRIAL APPLICABILITY The tool cooling apparatus using nitrogen gas and the tool cooling method using nitrogen gas of the present invention are advantageous in that the tool and the workpiece can be cooled effectively by penetrating the tool even at high speed.
The tool cooling apparatus using nitrogen gas and the tool cooling method using nitrogen gas according to the present invention are environmentally friendly since they are harmless to the human body and use nitrogen gas as a main component of the air and improve the tool life without affecting the safety of workers There is an effect that can be.

Description

Technical Field [0001] The present invention relates to a tool cooling apparatus and a tool cooling method using nitrogen gas,

The present invention relates to a tool cooling apparatus using nitrogen gas and a tool cooling method using nitrogen gas. More particularly, the present invention relates to a tool for cooling a workpiece by effectively using a nitrogen gas A cooling device, and a tool cooling method using nitrogen gas.

The process of cutting, grinding and grinding a workpiece using a machine tool has traditionally been used for a long time in the machinery industry.

In recent years, it has become possible to manufacture a high-performance and high-strength tool while advancing the manufacturing technology of the tool. Due to the development of such tools, high-speed workpieces can be machined at high speed. When a high-strength workpiece is machined at high speed using a tool, high heat is generated in the cutting process. If such cutting heat is not effectively cooled, there is a problem that the tool life is shortened. High-strength tools are expensive because of their high performance, so that if the tool is damaged by cutting heat, the cost of processing the workpiece will increase.

Conventionally, a method of machining a workpiece while spraying a water-soluble or non-water-soluble cutting fluid onto a cutting surface of a tool has been frequently used. The performance of a machine tool such as a milling machine is improved with the improvement of the performance of the tool. When the tool is rotated at a high speed, the use of such a cutting fluid alone can not effectively cool the tool. The cutting fluid can not penetrate to the cutting surface due to the centrifugal force due to the high-speed rotation of the tool, and the tool can not be cooled due to scattering. The cutting fluid may not penetrate to the cutting surface due to the air current around the tool due to the high speed rotation of the tool. Particularly in the case of the polishing process, the tool is rotated at a higher speed, so that the tool and the workpiece generate higher heat. However, the conventional cutting fluid injection method has a problem that the tool can not be sufficiently cooled.

A tool cooling apparatus using nitrogen gas of the present invention is contrived to solve such a problem and provides a tool cooling apparatus using nitrogen gas which can effectively cool the heat generated between tools and workpieces of a machine tool .

Further, a tool cooling method using nitrogen gas of the present invention is intended to provide a method of effectively cooling a tool by penetrating a cutting surface of a tool rotating at high speed.

In order to solve the above-mentioned problems, a tool cooling apparatus using nitrogen gas according to the present invention comprises: a nitrogen generating unit for collecting nitrogen in air to generate nitrogen gas; A cutting fluid supply unit for supplying a tool of a machine tool and a cutting fluid for cooling the workpiece; A mixing unit that mixes the nitrogen gas supplied from the nitrogen generating unit with the cutting fluid supplied from the cutting fluid supply unit; And a spray unit which receives a mixture of the mixed liquid and the nitrogen gas mixed in the mixing unit and injects the mixture through the cutting liquid nozzle onto the cut surface of the work.

Further, the tool cooling method using the nitrogen gas of the present invention comprises the steps of: (a) supplying a cutting fluid for cooling a tool and a workpiece of a machine tool; (b) trapping nitrogen in the air to generate nitrogen gas; (c) mixing the nitrogen gas with the cutting fluid; And (d) spraying the cutting fluid mixed with the nitrogen gas onto the cutting surface of the work.

INDUSTRIAL APPLICABILITY The tool cooling apparatus using nitrogen gas and the tool cooling method using nitrogen gas of the present invention are advantageous in that the tool and the workpiece can be cooled effectively by penetrating the tool even at high speed.

The tool cooling apparatus using nitrogen gas and the tool cooling method using nitrogen gas according to the present invention are environmentally friendly since they are harmless to the human body and use nitrogen gas as a main component of the air and improve the tool life without affecting the safety of workers There is an effect that can be.

1 is a block diagram of a tool cooling apparatus using nitrogen gas according to a first embodiment of the present invention.
2 is a cross-sectional view of the mixing unit shown in Fig.
3 is a sectional view taken along line III-III of the mixing unit shown in Fig.
4 is a block diagram of a tool cooling apparatus using nitrogen gas according to a second embodiment of the present invention.
5 is a sectional view showing a pressing module of the tool cooling apparatus using the nitrogen gas shown in FIG.
6 is a cross-sectional view of the dissolving unit of the tool cooling apparatus using the nitrogen gas shown in Fig.

Hereinafter, a tool cooling apparatus using nitrogen gas and a tool cooling method using nitrogen gas according to the present invention will be described in detail with reference to the drawings.

Fig. 1 is a block diagram of a tool cooling apparatus using nitrogen gas according to a first embodiment of the present invention, Fig. 2 is a cross-sectional view of the mixing unit shown in Fig. 1, Fig.

1 to 3, a tool cooling apparatus using nitrogen gas according to the first embodiment includes a nitrogen generating unit 120, a cutting liquid supply unit 110, a mixing unit 130, and a spray unit 160 .

The nitrogen generating unit 120 collects nitrogen in the air to generate nitrogen gas. The nitrogen generating unit 120 may generate nitrogen gas by a pressure swing absorption (PSA) method. The nitrogen gas is generated by the pressure swing adsorption method, so that high purity nitrogen can be efficiently produced while using relatively little energy. Also, nitrogen gas separation can be effectively performed by using CMS (Carbon Molecular Sieve) as an adsorbent to adsorb and separate only nitrogen from the gases contained in the air.

The cutting fluid supply unit 110 supplies the cutting fluid. A conventional water-soluble, water-insoluble cutting fluid for cooling and lubricating the workpiece 101 and the tool 102 that are cut by the machine tool is used.

The nitrogen supplied from the nitrogen generating unit 120 and the cutting liquid supplied from the cutting fluid supply unit 110 are transferred to the mixing unit 130 and mixed with each other. The mixing unit 130 mixes the nitrogen gas and the cutting fluid so that the nitrogen gas is mixed with the cutting fluid in the form of bubbles. A cutting fluid supply pump 111 is disposed between the cutting fluid supply unit 110 and the mixing unit 130 to continuously supply the cutting fluid to the mixing unit 130. A check valve 121 is provided between the nitrogen generating unit 120 and the mixing unit 130 to prevent nitrogen gas from flowing backward.

2 and 3, the mixing unit 130 includes a cutting fluid inlet 132, a nitrogen inlet 133, and a mixing space 134. The cutting fluid supplied from the cutting fluid supply unit 110 is transferred to the mixing space 134 through the cutting fluid inlet 132. The nitrogen gas supplied from the nitrogen generating unit 120 flows through the nitrogen inlet 133 and is transferred to the mixing space 134. The cutting fluid and the nitrogen gas meet each other in the mixing space 134 and the nitrogen gas is mixed with the cutting fluid in the form of micro bubbles.

A nitrogen gas oil space 135 is disposed between the nitrogen inlet 133 and the mixing space 134 to improve microbubble generation efficiency by the nitrogen gas. The nitrogen gas introduced into the nitrogen inlet 133 is transferred to the mixing space 134 via the nitrogen gas-containing space 135. In this embodiment, the mixing space 134 is formed in a cylindrical shape, and the nitrogen light-emitting space 135 is formed to surround the outer diameter of the mixing space 134, as shown in FIGS. Nitrogen mixing holes 136 are formed between the nitrogen gas-fired space 135 and the mixing space 134 and nitrogen gas is injected into the mixing space 134 through the nitrogen mixing holes 136. Referring to FIG. 3, the nitrogen mixing holes 136 are formed to extend along the radial direction of the mixing space 134, and a plurality of nitrogen mixing holes 136 are arranged at regular intervals along the circumferential direction.

It is preferable that the width L of the nitrogen diesel oil space 135 is larger than the inner diameter of the nitrogen inlet 133 and the inner diameter of the nitrogen mixing hole 136 is smaller than the width L of the nitrogen diesel oil space 135. The width L of the nitrogen light oil room space 135 is formed to be larger than the inner diameter of the nitrogen light oil inlet 133 so that the nitrogen gas can smoothly flow into the nitrogen light oil space 135 As shown in FIG. The inner diameter of the nitrogen mixing hole 136 is made smaller than the width L of the nitrogen diesel fuel space 135 such that the nitrogen gas flows into the mixing space 134 at a pressure higher than the nitrogen diesel fuel space 135. This has the advantage that the production efficiency of microbubbles by nitrogen gas is improved. It is possible to improve the generation efficiency of microbubbles by the nitrogen gas by controlling the ratio of the width L and the height D of the nitrogen light oil space 135.

The pressure at which the nitrogen gas is introduced into the mixing space 134 can be made larger than the pressure at which the nitrogen gas is introduced into the nitrogen gas space 135 by making the inner diameter of the nitrogen mixing hole 136 smaller than the inner diameter of the nitrogen inlet 133 . By using such a structure, it is possible to push the nitrogen gas into the mixing space 134 with a strong pressure to improve the generation efficiency of micro bubbles.

In the mixing space 134, the cutting liquid mixed with the nitrogen gas in the form of micro bubbles is transferred to the injection unit and sprayed on the cutting surface of the tool 102. The injection unit 160 of this embodiment has the same structure as the nozzle 160 installed in the mixing space 134 as shown in FIG. In some cases, it is also possible to connect the flow path to the mixing space 134 to dispose the injection unit at a position spaced apart from the mixing unit 130.

Nitrogen gas dissolved in the cutting fluid in the form of micro bubbles expands under atmospheric pressure and is discharged into the air. The nitrogen gas dissolved in the cutting fluid is rapidly expanded and mixed into the air. As the nitrogen gas expands, it instantaneously generates a high temperature and then absorbs the surrounding heat while expanding adiabatically. This has the advantage that the tool 102 rotating at high speed or friction and the cutting surface of the work 101 can be effectively cooled. Also, the micro bubble nitrogen gas can effectively penetrate the cutting surface of the tool 102 rotating at a high speed due to the increased volume of the ultrasonic wave and the nitrogen gas generated during the expansion of the micro bubble nitrogen gas.

In the case of a conventional cutting fluid cooling method, in the case of a tool rotating or operating at high speed, even if the cutting fluid is sprayed due to the rotation speed of the tool and the air flow around the tool, the cutting fluid can not penetrate to the cutting surface of the tool, The workpiece can not be cooled. In such a case, the life of the expensive tool is shortened and the surface roughness of the workpiece is also increased. However, in the case of the tool cooling apparatus using the nitrogen gas of this embodiment, it is possible for the cutting liquid and the nitrogen gas to penetrate to the cutting face of the tool 102 by micro bubbles caused by the nitrogen gas and expansion of the nitrogen gas. When the cutting liquid moves only to the vicinity of the tool 102 by the jetting pressure of the jetting unit 160, the nitrogen gas inside the cutting liquid expands and fills the surrounding space at a very high speed, . Since the nitrogen gas has lubrication characteristics, the lubrication characteristics of the cutting fluid are complemented, and the endothermic reaction due to adiabatic expansion of the nitrogen gas cools the heat of the tool 102.

There have been cases where microbubbles using oxygen or nitrogen gas have been used in other industrial fields, but there have been no cases in which they are used for cutting and polishing processes using machine tools. The present invention has been an unsolved problem for a long time due to the change of the idea. Particularly, since the performance of the machine tool has recently been improved and the cutting speed has been improved, the problem of cooling and lubrication of the tool 102 and the workpiece 101, It is characterized by its breakthrough.

Next, a tool cooling apparatus using the nitrogen gas according to the second embodiment of the present invention will be described with reference to Figs. 4 to 6. Fig.

FIG. 4 is a block diagram of a tool cooling apparatus using nitrogen gas according to the second embodiment, FIG. 5 is a sectional view showing a pressing module of the tool cooling apparatus using nitrogen gas shown in FIG. 4, Sectional view of a melting unit of a tool cooling apparatus using nitrogen gas shown in Fig.

4 to 6, a tool cooling apparatus using nitrogen gas according to the present embodiment includes a nitrogen generating unit 220, a cutting liquid supplying unit 210, a mixing unit 230, a dissolving unit 240, 250 and an injection unit 260.

The nitrogen generating unit 220 and the cutting liquid supplying unit 210 are the same as the nitrogen generating unit 120 and the cutting liquid supplying unit 110 of the first embodiment.

The nitrogen supplied from the nitrogen generating unit 220 and the cutting fluid supplied from the cutting fluid supplying unit 210 are transferred to the mixing unit 230 and mixed with each other. The mixing unit 230 mixes the nitrogen gas and the cutting fluid so that the nitrogen gas is mixed with the cutting fluid in the form of bubbles. A check valve 221 is provided between the nitrogen generating unit 220 and the mixing unit 230 to prevent nitrogen gas from flowing backward. The mixing unit 230 of this embodiment may be formed in a structure similar to that of the mixing unit 130 of the first embodiment described above with reference to FIGS. 2 and 3, or may be configured to mix the cutting liquid with nitrogen gas It is also possible.

The cutting liquid in which the nitrogen gas is mixed in the mixing unit 230 is transferred to the dissolving unit 240. The dissolving unit 240 includes a dissolving tank 242, a dissolving pump 241, and a pressing module 243.

The dissolving pump 241 sucks the cutting fluid transferred from the mixing unit 230 and transfers it while applying pressure to the dissolving tank 242.

Referring to FIG. 6, the dissolution tank 240 of the dissolution unit 240 is filled with a ceramic ball 247. The cutting fluid mixed with the nitrogen gas flows through the ceramic balls 247 made of porous ceramics at a high pressure, and the solubility of the nitrogen gas is improved. In order to improve the efficiency of the dissolving unit 240, the dissolution inlet 244 through which the cutting liquid mixed with the nitrogen gas flows into the dissolving tank 242 is disposed on the upper side of the dissolving tank 242, It is preferable that the dissolution outlet 245 through which the cutting fluid mixed with the nitrogen gas flows in the inside of the dissolution tank 242 is disposed below the dissolution tank 242. The opportunity of contact with the ceramic ball 247 between the dissolution inlet 244 and the dissolution outlet 245 and the contact time are increased as the dissolution inlet 244 is disposed on the upper side and the dissolution outlet 245 is disposed on the lower side, And as a result, a cutting fluid having increased solubility of nitrogen gas is produced.

Between the dissolution pump 241 and the dissolution tank 242, a pressurizing module 243 as shown in FIG. 2 is preferably provided. The pressurizing module 243 is disposed on the flow path of the cutting fluid in which the nitrogen gas is mixed to improve the solubility of the nitrogen gas in the cutting fluid. The pressing module 243 has a plurality of through holes 2432 formed in the body portion 2431. The through hole 2432 is formed so that the inner diameter decreases along the flow direction of the cutting fluid. That is, the through hole 2432 of the pressure module 243 is formed such that the inner diameter of the outlet is smaller than that of the inlet. So that the pressure of the cutting fluid rises through the through hole 2432. By the action of the through hole 2432 of the pressing module 243 using the Bernoulli's law, the nitrogen gas is gradually dissolved in the cutting fluid at a higher concentration.

As described above, the cutting fluid passed through the pressure module 243 is stored in the dissolution tank 242 at a high pressure. The cutting fluid stays in the dissolution tank 242 due to the high pressure applied by the dissolution pump 241, and the nitrogen gas gradually dissolves in the cutting fluid.

Although the cutting liquid having improved solubility of nitrogen gas in the dissolution tank 242 is directly transferred to the injection unit 260 and sprayed on the cutting surface of the tool 102, in the tool cooling apparatus using the nitrogen gas of this embodiment, The cutting fluid is transferred to the injection unit 260 via the tank 250. [ The cutting liquid in which the nitrogen gas is sufficiently dissolved in the dissolving unit 240 is transferred to and stored in the storage tank 250. The dissolving unit 240 transfers the cutting liquid sufficiently dissolved with nitrogen gas to the storage tank 250 to empty the dissolving tank 242, and then receives the next cutting fluid to dissolve the nitrogen gas.

The storage tank 250 stores the oil well at a sufficient pressure to maintain the solubility of the nitrogen gas.

The cutting fluid stored in the storage tank 250 is transferred to the injection unit 260 and is sprayed onto the tool 102 and the work 101. The injection unit 260 has an injection pump 261 and a nozzle 262. The injection pump 261 sucks the cutting fluid stored in the storage tank 250 and presses it in the direction of the nozzle 262. The cutting liquid ejected from the nozzle 262 is sprayed on the cutting surface of the work 101 and the tool 102 to protect the tool 102 and cool it. The nozzle 262 is installed so that the tool 102 of the machine tool can supply the cutting fluid to the cutting surface on which the workpiece 101 is to be cut. Optionally, the injection unit 260 may have a plurality of nozzles 262. In the case where a plurality of injection nozzles 262 are provided, the cutting liquid may be injected in two or more directions with respect to one tool 102, or the cutting liquid may be supplied simultaneously to a plurality of machine tools .

The nitrogen gas dissolved at a high pressure causes microbubbles to be generated inside the cutting fluid while the cutting fluid is ejected through the nozzle 262 at atmospheric pressure. The nitrogen gas in the micro bubble state dissolved in the cutting fluid is discharged into the atmospheric air.

Although the preferred embodiments of the present invention have been described above, the scope of the present invention is not limited to those described above and shown in the drawings.

For example, although the dissolving unit 240 has been described as having the pressing module 243, it may also constitute a dissolving unit that does not include the pressing module 243.

In some cases, it is also possible to constitute a tool cooling apparatus using nitrogen gas not having the storage tank 250. In this case, the cutting liquid in which the nitrogen gas is dissolved is directly delivered from the dissolution unit 240 to the injection unit 260 without passing through the storage tank, and is sprayed onto the cutting surface of the tool 102.

Hereinafter, a process of performing the tool cooling method using the nitrogen gas by using the tool cooling apparatus using the nitrogen gas of the present invention described above will be described.

First, cutting fluid for cooling the tool 102 of the machine tool and the workpiece 101 is supplied (step (a)). The cutting fluid is supplied by using the above-described cutting fluid supply units (110, 210).

At the same time, the nitrogen generating units 120 and 220 described above are used to collect nitrogen in the air to generate nitrogen gas (step (b)).

Next, nitrogen gas is mixed into the cutting fluid in the mixing units 130 and 230 (step (c)).

The cutting liquid in which the nitrogen gas is mixed is delivered to the dissolving unit 240. The dissolving unit 240 dissolves nitrogen gas into the cutting fluid by applying pressure to the cutting fluid mixed with the nitrogen gas (step (e)). As described above, the cutting fluid is introduced into the dissolving tank 242 via the pressing module 43 having a plurality of through holes 2432 whose inner diameters decrease along the flow direction of the cutting fluid, thereby improving the solubility of the nitrogen gas . As the nitrogen gas and the cutting fluid transferred to the dissolution tank 242 are stored in the dissolution tank 242 at a high pressure, the solubility of the nitrogen gas in the cutting fluid is improved.

The cutting liquid in which the nitrogen gas is fully dissolved can be stored in the storage tank 250 and transferred directly from the dissolution tank 242 to the spray unit 260 to spray the cutting surface of the tool 102, (Step (d)).

According to the tool cooling method using the nitrogen gas of the present invention as in the tool cooling apparatus using nitrogen gas of the present invention described above, the cutting liquid and the nitrogen gas can be deeply penetrated to the tool 102 and the cutting surface, 102 and the workpiece 101 can be improved.

In addition, since nitrogen gas, which is a main component of air, is used, there is an advantage that the nitrogen gas discharged after the injection does not pollute the environment and does not damage the safety of the operator. That is, when the tool cooling apparatus using nitrogen gas and the tool cooling method using nitrogen gas of the present invention are carried out, there is an advantage that an extremely effective machining process can be performed by an environmentally friendly method. The tool cooling apparatus using nitrogen gas and the tool cooling method using nitrogen gas of the present invention can be used not only in cutting process but also in polishing process.

110, 210: Cutting liquid supply unit 120, 220: Nitrogen generating unit
130, 230: mixing unit 240: melting unit
241: dissolving pump 242: dissolving tank
243: Pressure module 250: Storage tank
260: injection unit 261: injection pump
262: nozzle 101: workpiece
102: Tools

Claims (12)

A nitrogen generating unit for collecting nitrogen in the air to generate nitrogen gas;
A cutting fluid supply unit for supplying a tool of a machine tool and a cutting fluid for cooling the workpiece;
A mixing unit that mixes the nitrogen gas supplied from the nitrogen generating unit with the cutting fluid supplied from the cutting fluid supply unit;
A spray unit that receives a mixture of the mixed liquid and the nitrogen gas mixed in the mixing unit and injects the mixture through a cutting liquid nozzle onto a cutting surface of the workpiece; And
A dissolving tank for receiving and storing the nitrogen gas and the cutting liquid mixed in the mixing unit and a dissolving pump for applying pressure to the dissolving tank so that the nitrogen gas is dissolved in the dissolving tank, And a dissolving unit for transferring the cutting liquid in which the nitrogen gas stored in the dissolving tank is dissolved to the spray unit,
Wherein the spraying unit is supplied with a cutting fluid in which nitrogen gas is dissolved in the dissolving unit and is sprayed onto a cutting surface of the workpiece. The method according to claim 1,
Wherein the mixing unit is connected to the cutting fluid inflow port into which the cutting fluid supplied from the cutting fluid supply unit flows, the nitrogen inflow port into which the nitrogen gas supplied from the nitrogen generating unit flows, A mixing space in which a cutting fluid and nitrogen are mixed, and a nitrogen light oil space disposed between the nitrogen inlet and the mixing space,
The nitrogen-containing space has a width larger than an inner diameter of the nitrogen inlet,
Wherein the inner diameter of the nitrogen mixing hole formed between the nitrogen gas-fired space and the mixed space is smaller than the width of the nitrogen gas-fired space. 3. The method of claim 2,
Wherein the mixing space is formed in a cylindrical shape,
The nitrogen gas-tight space is formed to surround the outer diameter of the mixing space,
Wherein the nitrogen mixing hole is formed to extend in the radial direction of the mixing space. The method of claim 3,
And the inner diameter of the nitrogen mixing hole is smaller than the inner diameter of the nitrogen inlet. delete The method according to claim 1,
The melting tank of the dissolution unit is filled with a ceramic ball,
Wherein a dissolution inlet through which the cutting liquid mixed with the nitrogen gas flows into the dissolution tank is disposed on the upper side of the dissolution tank,
And a dissolution outlet through which the cutting fluid mixed with the nitrogen gas flows out from the dissolution tank is disposed below the dissolution tank. The method according to claim 1,
And a storage tank disposed between the dissolution unit and the spray unit for receiving and storing the cutting liquid in which the nitrogen gas is dissolved in the dissolution unit,
Wherein the spray unit further comprises a spray pump for delivering the cutting fluid stored in the storage tank to the nozzle. The method according to claim 1,
Wherein the dissolution unit is disposed on a flow path of the cutting fluid in which the nitrogen gas is mixed to form a plurality of through holes having an inner diameter decreasing along the flow direction of the cutting fluid so as to improve the solubility of the nitrogen gas in the cutting fluid, Further comprising a pressure module formed on the substrate. (a) supplying a cutting fluid for cooling a tool and a workpiece of a machine tool;
(b) trapping nitrogen in the air to generate nitrogen gas;
(c) mixing the nitrogen gas with the cutting fluid;
(d) spraying the cutting liquid mixed with the nitrogen gas onto a cutting surface of the workpiece; And
(e) dissolving the nitrogen gas in the cutting fluid by applying pressure to the cutting fluid mixed with the nitrogen gas in the step (c)
Wherein the step (d) comprises the step of injecting the cutting fluid in which the nitrogen gas is dissolved in the step (e) to generate the nitrogen gas microbubble in the cutting fluid. delete 10. The method of claim 9,
Wherein the step (e) further comprises the step of increasing the solubility of the nitrogen gas by passing the time while the cutting liquid in which the nitrogen gas is dissolved by pressure is stored in the dissolution tank . 12. The method of claim 11,
In the step (e), pressure is applied to the cutting fluid through the pressurizing module having a plurality of through holes having an inner diameter decreasing along the flow direction of the cutting fluid, so that the cutting fluid is introduced into the dissolving tank A method for cooling a tool using nitrogen gas.

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