KR20170074613A - Mechanical milling system and method - Google Patents

Mechanical milling system and method Download PDF

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Publication number
KR20170074613A
KR20170074613A KR1020150184100A KR20150184100A KR20170074613A KR 20170074613 A KR20170074613 A KR 20170074613A KR 1020150184100 A KR1020150184100 A KR 1020150184100A KR 20150184100 A KR20150184100 A KR 20150184100A KR 20170074613 A KR20170074613 A KR 20170074613A
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KR
South Korea
Prior art keywords
milling
chamber
camera
balls
impeller
Prior art date
Application number
KR1020150184100A
Other languages
Korean (ko)
Inventor
이희춘
최이식
문성환
장계원
유호탁
Original Assignee
주식회사 사파이어테크놀로지
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Priority to KR1020150184100A priority Critical patent/KR20170074613A/en
Publication of KR20170074613A publication Critical patent/KR20170074613A/en

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/02—Making metallic powder or suspensions thereof using physical processes
    • B22F9/04—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C17/00—Disintegrating by tumbling mills, i.e. mills having a container charged with the material to be disintegrated with or without special disintegrating members such as pebbles or balls
    • B02C17/16—Mills in which a fixed container houses stirring means tumbling the charge
    • B02C17/163—Stirring means
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C17/00—Disintegrating by tumbling mills, i.e. mills having a container charged with the material to be disintegrated with or without special disintegrating members such as pebbles or balls
    • B02C17/18—Details
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C17/00—Disintegrating by tumbling mills, i.e. mills having a container charged with the material to be disintegrated with or without special disintegrating members such as pebbles or balls
    • B02C17/18—Details
    • B02C17/1805—Monitoring devices for tumbling mills
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/02—Making metallic powder or suspensions thereof using physical processes
    • B22F9/04—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling
    • B22F2009/041—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling by mechanical alloying, e.g. blending, milling
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/02—Making metallic powder or suspensions thereof using physical processes
    • B22F9/04—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling
    • B22F2009/043—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling by ball milling

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  • Engineering & Computer Science (AREA)
  • Food Science & Technology (AREA)
  • Machine Tool Sensing Apparatuses (AREA)

Abstract

The present invention relates to a mechanical milling system and method, wherein the mechanical milling system comprises a milling chamber provided with an internal space and a window formed on the side wall; A plurality of balls loaded into the interior space of the milling chamber to mill the milling material; An impeller installed in an inner space of the milling chamber to rotate the plurality of balls; A camera for photographing the inner wall of the milling chamber, the milling material, the ball and the impeller during the milling process through the window; And a computer device capable of monitoring an image photographed by the camera.

Description

[0001] Mechanical milling system and method [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanical milling system and method, and more particularly, to a mechanical milling system capable of grasping the state of equipment wear during a milling process, securing process stability and reliability, And methods.

For the last 20 years, cathode materials for lithium-ion batteries have been mainly applied to carbon-based cathode materials. Carbon-based active materials are largely classified into crystalline and amorphous active materials. Up to now, graphite-based materials, which are crystalline materials, have been applied to almost all lithium ion batteries. However, due to the need for high capacity lithium ion batteries, Research on materials has attracted considerable attention.

U.S. Patent No. 7,906,239 discloses SiMC (M is a metal and C is carbon) used as an electrode of a lithium ion battery, and these SiMCs are compositions manufactured by applying a mechanical milling process technology. This mechanical milling process is a technique of dispersing fine Si crystals on a metal silicide matrix during the milling process while simultaneously adding carbon with excellent conductivity.

Thus, when refining metal silicides and Si with high hardness, mechanical milling process techniques should be used.

Mechanical milling process technology is a powder metallurgy technology that can produce powder uniformly and finely by repeatedly performing cold welding and fracture processes.

Korean Patent Laid-Open Publication No. 10-2011-0010987 discloses that a mixed powder is put into a rotating container in a contact rotary type high-speed milling apparatus together with a steel ball, and then the rotary shaft is rotated at 800 to 1200 rpm in a vacuum or argon atmosphere, and the rotary container is rotated at 2000 to 2900 rpm A method of manufacturing a nanoceramic dispersion strengthening alloy / metal powder in a short time using a high speed mechanical milling apparatus including a step of rotating in a direction opposite to the rotation direction of the rotation axis and milling for a short time of 30 to 70 minutes has been disclosed , There is no technical structure for grasping the abrasion of the equipment generated during the milling process, which may lead to reduction in the life of the equipment and process instability.

This mechanical milling process technique causes abrasion of the milling equipment by materials having high hardness and in particular, abrasion of the milling vessel wall and milling ball acts as an internal powder contamination source, thereby impairing the reliability of the milling process. And to study the milling equipments and methods to solve these problems.

United States Patent Application Publication No. US 7,906,239 Korean Patent Publication No. 10-2011-0010987

SUMMARY OF THE INVENTION It is an object of the present invention to provide a mechanical milling system and method capable of securing stability of a milling process and improving reliability of the milling process.

Another object of the present invention is to provide a mechanical milling system capable of real-time grasp of the inner wall of the milling chamber, the milling material, the ball and the impeller, thereby preventing the risk of overloading, increasing the service life of the equipment, And a method.

According to an aspect of the present invention, there is provided a mechanical milling system including a milling chamber having an inner space and a window formed on a side wall thereof;

A plurality of balls loaded into the interior space of the milling chamber to mill the milling material;

An impeller installed in an inner space of the milling chamber to rotate the plurality of balls;

A camera for photographing the inner wall of the milling chamber, the milling material, the ball and the impeller during the milling process through the window; And

And a computer device capable of monitoring an image photographed by the camera.

In a mechanical milling system according to an embodiment of the present invention, the window may be embodied as sapphire glass.

In a mechanical milling system according to an embodiment of the present invention, a light source capable of illuminating the inner space of the milling chamber may be further included.

In the mechanical milling system according to an embodiment of the present invention, an analysis program for analyzing the image transmitted from the camera and extracting problems in the milling process may be installed in the computer device.

In the mechanical milling system according to an embodiment of the present invention, the computer apparatus stores data on the range of the rotation band intervals of the plurality of balls according to the diameter of the chamber and the velocity of the impeller, When a plurality of balls of the image transmitted from the camera are out of the range of the rotation band interval, it can be determined that the milling process in which the problem has occurred is being performed.

According to another aspect of the present invention, there is provided a mechanical milling method comprising: charging a milling material into an inner space of a milling chamber in which a plurality of balls are installed and an impeller is installed;

Rotating the plurality of balls by rotation of the impeller to perform a milling process of the milling material;

Illuminating an inner space with a light source installed in a side wall of the milling chamber;

Photographing an inner space of the milling chamber with a camera through a window formed in a side wall of the milling chamber; And

And monitoring the image photographed by the camera in a computer device.

In the mechanical milling system according to an embodiment of the present invention, an analysis program for analyzing the image transmitted from the camera and extracting the problems of the milling process is installed in the computer device. In accordance with the diameter of the chamber and the speed of the impeller Wherein the step of monitoring the images photographed by the camera at the computer device comprises the steps of: storing a plurality of balls of the image transmitted from the camera in a rotation band interval If it is out of the range, it may be determined that the milling process in which the problem has occurred is being performed.

According to the present invention, there is an advantage that the reliability of the milling process can be secured and the reliability of the milling process can be improved by preventing the problems of the milling process in advance with an image captured in real time by the camera.

According to the present invention, it is possible to grasp the wear state of the inner wall of the milling chamber, the milling material, the ball and the impeller in real time to prevent the risk of overload, increase the service life of the equipment, and maintain the equipment efficiently.

According to the present invention, the milling process in which a problem occurs can be determined by comparing the data of the range of the rotation zone of the ball stored in the computer device with the range of the rotation zone of the plurality of balls of the image transmitted from the camera, There is an advantage that the wear of the side wall, the ball and the impeller can be detected quickly.

1 is a conceptual perspective view for explaining a mechanical milling system according to the present invention;
2 is a flow diagram of a mechanical milling method according to the present invention,
3 is a view for explaining a path in which a plurality of balls are rotated in a milling chamber according to the present invention.

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

1 is a conceptual perspective view illustrating a mechanical milling system according to the present invention.

The mechanical milling system according to the present invention includes a milling chamber 100 provided with an inner space and having a window 110 on a side wall thereof; A plurality of balls (120) loaded into the inner space of the milling chamber (100) to mill the milling material; An impeller 130 installed in an inner space of the milling chamber 100 to rotate the plurality of balls 120; A camera (140) for photographing the inner wall of the milling chamber (100), the milling material, the ball (120) and the impeller (130) during the milling process through the window (110); And a computer device 150 capable of monitoring an image photographed by the camera 140. [

In the mechanical milling system according to the present invention, the impeller 130 is installed in the inner space of the milling chamber 100, and the plurality of balls 120 are rotated by the rotating impeller 130 to mill the milling material . In the milling chamber 100, a driving motor and a cooling water line, which are not shown in the figure, are connected.

In the present invention, the inner space of the milling chamber 100 is dark, and the inner space of the milling chamber 100 is illuminated so that a clear image of the milling material, the ball 120 and the impeller 130 can be taken during the milling process A light source 200 can be installed on the inner wall of the milling chamber 100. [

Accordingly, the present invention can be applied to the camera 140 through the window 110 formed in the milling chamber 100, the state of the inner wall of the milling chamber 100, the milling material, the ball 120 and the impeller 130 during the milling process By monitoring the image on the computer device 150, problems occurring in the milling process can be grasped in real time, and reliability of the milling process can be improved. Here, the computer device 150 is a device including a computer main body and a monitor.

Meanwhile, as the impeller 130, which is a rotating body installed in the inner space of the milling chamber 100, rotates, the milling process rotates the ball 120 and the powder as a milling material. At this time, the rotating ball 120 and the ball 120 collide with each other, and powder is caught or collided between the colliding balls 120, and the powder is crushed.

Here, the ball 120 loaded in the inner space of the milling chamber 100 by the high-speed rotation of the impeller 130 rotates and collides with the milling material.

In addition, since the milling process is performed by welding the powders to each other due to the collision with the balls, the powders of different compositions can be uniformly dispersed.

Here, when a high energy milling process for milling a milling material such as a Si composite material having a high hardness in the milling chamber into fine particles is performed, the inner wall of the milling chamber 100, the balls 120 And the impeller 130 are worn and mixed with the milling material, or the shape of the impeller 130 is deformed to change the rotational locus of the ball, so that an unstable milling process can be performed.

Accordingly, the present invention can prevent the problems of the milling process in advance by securing the stability of the milling process and improve the reliability of the milling process.

In addition, the present invention provides a method and system for grinding the inner wall of the milling chamber 100, the milling material, the ball 120 and the impeller 130 in real time to prevent overloading, increase the life of the equipment, It has the advantage of maintenance.

The window 110 formed on the sidewall of the milling chamber 100 is preferably formed of a high-hardness sapphire glass so as not to be damaged by a collision of a high-hardness milling material during the milling process.

2 is a flow chart of a mechanical milling method according to the present invention.

The mechanical milling method according to the present invention is characterized in that a milling material is charged into an inner space of a milling chamber in which a plurality of balls are loaded and an impeller is installed (S100), and the milling material is milled (S110). Then, the inner space is illuminated with a light source installed in the inner wall of the milling chamber (S120), and the inner space of the milling chamber is photographed with a camera through a window formed on a sidewall of the milling chamber (S130). Then, the image photographed by the camera is monitored by a computer device (S140).

Here, the 'S150' step of monitoring the image photographed by the camera in the computer device is performed by real-time transmission of the image photographed by the camera to the computer device so that the operator can recognize the problem of the milling process by confirming with eyes.

In addition, in the present invention, an analysis program for analyzing images transmitted from a camera and extracting problems in a milling process may be installed in a computer device, and the analysis program may be configured to monitor images photographed by the camera.

3 is a view for explaining a path in which a plurality of balls are rotated in a milling chamber according to the present invention.

The impeller 130 installed in the milling chamber 100 is rotated to rotate a plurality of balls 120 loaded in the inner space 101 of the milling chamber 100 to perform a milling process. Here, the plurality of balls 120 to be rotated have a path rotated in a predetermined path in the inner space 101 of the milling chamber 100.

That is, the inner space 101 of the milling chamber 100 is cylindrical, the impeller 130 is rotated around the center of the cylindrical shape, and the plurality of balls 120 are cylindrical edges 102 spaced from the center of the cylindrical shape ) Of the rotor.

At this time, a plurality of balls 120 are rotated along the cylindrical edge 102 in a distance L (referred to as a 'rotation band gap') from a cylindrical edge 102 to a spaced position.

Meanwhile, in the present invention, it is possible to analyze the image transmitted from the camera using the analysis program installed in the computer device, thereby extracting problems in the milling process.

As an example, the computer device stores data on the range of the rotation belt intervals of a plurality of balls 120 according to the diameter of the chamber and the speed of the impeller, as a judgment standard of a milling process having no problem and reliability, When a plurality of balls 120 of the image transmitted from the camera are out of data on the stored range of the rotation belt interval, it is determined that the milling process in which the problem has occurred is being performed.

As shown in Table 1, the computer device stores data on the range of the rotation belt intervals of the plurality of balls 120 according to the diameter of the chamber and the speed of the impeller.

Chamber Diameter (mm) Impeller Speed (RPM) Rotation band gap range (mm)
400
350 80-100 400 45 to 60 450 30 to 40
500
350 60 to 75 400 40 to 50 450 20 ~ 30

In Table 1, when the milling process is performed with the impeller speed set to 450 RPM in a milling chamber having a diameter of 400 mm, when the rotation band interval range of a plurality of balls 120 of an image transmitted from the camera is 25 mm, The analysis program detects that the stored rotation band interval is out of the range, and determines that the milling process is being performed with a problem of reduced reliability.

Here, when the plurality of balls 120 are out of the range of the rotation belt interval stored in the computer device during the milling process, wear of one of the inner wall of the milling chamber 100, the ball 120, and the impeller 130 occurs, An unstable milling process in which reliability is deteriorated due to the deviation of the rotating shaft 120 from the stable rotation path.

That is, in the present invention, the accumulated data as shown in Table 1 is prepared through a preliminary experiment on the range of the rotation band intervals of a plurality of balls 120 according to the diameter of the chamber and the speed of the impeller, The analysis program compares the data of the rotation range of the ball stored in the computer device with the range of the rotation of the plurality of balls 120 of the image transmitted from the camera and stops the equipment in case of a milling process error, And equipment life.

By managing the equipment through the real-time monitoring device, it is possible to compensate the disadvantages of the existing process technology and to secure the stable powder powder and the life (safety) of the equipment.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be construed as limited to the embodiments set forth herein. Various changes and modifications may be made by those skilled in the art.

The present invention is applied to a mechanical milling system capable of grasping the wear state of the equipment during milling process, securing stability and reliability of the process, increasing the life span, and efficiently maintaining the process.

100: milling chamber 101: inner space
102: edge 110: window
120: ball 130: impeller
140: camera 150: computer device
200: Light source

Claims (7)

A milling chamber provided with an inner space and having a window formed on its side wall;
A plurality of balls loaded into the interior space of the milling chamber to mill the milling material;
An impeller installed in an inner space of the milling chamber to rotate the plurality of balls;
A camera for photographing the inner wall of the milling chamber, the milling material, the ball and the impeller during the milling process through the window; And
And a computer device capable of monitoring an image photographed by the camera. 2. The mechanical milling system of claim 1, wherein the window is embodied as sapphire glass. 2. The mechanical milling system of claim 1, further comprising a light source capable of illuminating an interior space of the milling chamber. 2. The mechanical milling system according to claim 1, wherein an analysis program for analyzing an image transmitted from the camera and extracting problems in the milling process is installed in the computer device. 5. The apparatus of claim 4, wherein the computer device stores data on a range of rotation zone distances of the plurality of balls according to a diameter of the chamber and a velocity of the impeller, Is determined to be performing the milling process in which the problem has occurred when the ball of the ball exceeds the range of the rotational strip interval. Charging a milling material into an internal space of a milling chamber in which an impeller is installed and a plurality of balls are loaded;
Rotating the plurality of balls by rotation of the impeller to perform a milling process of the milling material;
Illuminating an inner space with a light source installed in a side wall of the milling chamber;
Photographing an inner space of the milling chamber with a camera through a window formed in a side wall of the milling chamber; And
And monitoring the image photographed by the camera in a computer device. The method according to claim 6,
An analysis program for analyzing an image transmitted from the camera and extracting a problem of a milling process is installed in the computer device and data on a rotation band interval range of the plurality of balls according to the diameter of the chamber and the velocity of the impeller In addition,
Wherein the step of monitoring the image photographed by the camera at the computer device comprises:
Wherein when the plurality of balls of the image transmitted from the camera are out of the range of the rotation band interval, the analysis program determines that the problem is occurring in the milling process.














KR1020150184100A 2015-12-22 2015-12-22 Mechanical milling system and method KR20170074613A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107597306A (en) * 2017-11-08 2018-01-19 铜陵市明诚铸造有限责任公司 A kind of abrading-ball based on graphical analysis crushes automation control system
CN107716080A (en) * 2017-11-08 2018-02-23 铜陵市明诚铸造有限责任公司 A kind of high-precision abrading-ball crushes control system
KR20230011065A (en) * 2021-07-13 2023-01-20 주식회사 엘지화학 A method for evaluating the wear of the filler and a method for seleting the filler composition

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107597306A (en) * 2017-11-08 2018-01-19 铜陵市明诚铸造有限责任公司 A kind of abrading-ball based on graphical analysis crushes automation control system
CN107716080A (en) * 2017-11-08 2018-02-23 铜陵市明诚铸造有限责任公司 A kind of high-precision abrading-ball crushes control system
CN107597306B (en) * 2017-11-08 2019-05-17 铜陵市明诚铸造有限责任公司 A kind of abrading-ball crushing automatic control system based on image analysis
KR20230011065A (en) * 2021-07-13 2023-01-20 주식회사 엘지화학 A method for evaluating the wear of the filler and a method for seleting the filler composition

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