KR101763488B1 - Glass edge grinding apparatus by using magneto-rheological fluids - Google Patents

Glass edge grinding apparatus by using magneto-rheological fluids Download PDF

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Publication number
KR101763488B1
KR101763488B1 KR1020150172320A KR20150172320A KR101763488B1 KR 101763488 B1 KR101763488 B1 KR 101763488B1 KR 1020150172320 A KR1020150172320 A KR 1020150172320A KR 20150172320 A KR20150172320 A KR 20150172320A KR 101763488 B1 KR101763488 B1 KR 101763488B1
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KR
South Korea
Prior art keywords
polishing
fluid
polishing slurry
magnetic field
supply unit
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KR1020150172320A
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Korean (ko)
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KR20170065936A (en
Inventor
조명우
하석재
김병찬
Original Assignee
인하대학교 산학협력단
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Priority to KR1020150172320A priority Critical patent/KR101763488B1/en
Publication of KR20170065936A publication Critical patent/KR20170065936A/en
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Publication of KR101763488B1 publication Critical patent/KR101763488B1/en

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B1/00—Processes of grinding or polishing; Use of auxiliary equipment in connection with such processes
    • B24B1/005—Processes of grinding or polishing; Use of auxiliary equipment in connection with such processes using a magnetic polishing agent
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B21/00—Machines or devices using grinding or polishing belts; Accessories therefor
    • B24B21/002—Machines or devices using grinding or polishing belts; Accessories therefor for grinding edges or bevels
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B21/00—Machines or devices using grinding or polishing belts; Accessories therefor
    • B24B21/18—Accessories
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B57/00—Devices for feeding, applying, grading or recovering grinding, polishing or lapping agents
    • B24B57/02—Devices for feeding, applying, grading or recovering grinding, polishing or lapping agents for feeding of fluid, sprayed, pulverised, or liquefied grinding, polishing or lapping agents
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B9/00—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor
    • B24B9/02—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor characterised by a special design with respect to properties of materials specific to articles to be ground
    • B24B9/06—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor characterised by a special design with respect to properties of materials specific to articles to be ground of non-metallic inorganic material, e.g. stone, ceramics, porcelain
    • B24B9/08—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor characterised by a special design with respect to properties of materials specific to articles to be ground of non-metallic inorganic material, e.g. stone, ceramics, porcelain of glass

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Ceramic Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)

Abstract

The present invention provides a polishing apparatus comprising: an abrasive belt moving along a roller arranged up and down; A fluid supply unit for supplying and recovering the magnetorheological fluid with the abrasive belt; A magnetic field supply unit disposed apart from both sides of the abrasive belt for applying a magnetic field to the magnetorheological fluid supplied to the abrasive belt; And a polishing slurry supply unit supplying the polishing slurry to the polishing belt; Wherein the magnetic field supply unit is provided with a glass edge polishing apparatus using a magnetorheological fluid having a distance in the center of the opposing face being greater than a distance in the edge.
In the present invention, the magnetic field supply portions disposed on both sides of the abrasive belt supplied with the magnetorheological fluid have a larger separation distance from the center, so that the magnetic field applied to the abrasive belt becomes uniform as a whole.

Description

Technical Field [0001] The present invention relates to a glass edge grinding apparatus using magneto-rheological fluids,

The present invention relates to a glass edge polishing apparatus using a magnetorheological fluid, and more particularly, to a polishing apparatus using a magnetorheological fluid, in which a magnetic field supply unit disposed on both sides of a polishing belt supplied with magnetorheological fluid has a greater distance from the center, And more particularly, to a glass edge polishing apparatus using a magnetorheological fluid capable of applying a magnetic field.

In recent years, there is an increasing demand for an integrated touch panel capable of simultaneously performing functions of a cover glass, an LCD panel, and a touch screen panel mounted above the display area, which are used for protection in displays.

After the completion of the panel, the integrated touch panel is completed by performing cutting and grinding processes in accordance with the size of the display to be used.

Currently, the main processing method used in the grinding process of the panel is a grinding process using a grinding wheel, but cracks and chips are generated on the surface and edge of the glass, There is a problem that fine particles are generated.

In order to solve the above problem, a technique of grinding a touch panel by a polishing system using magneto-rheological fluids (MR fluids) has been disclosed.

The magnetorheological fluid polishing system can control the polishing force by changing the stress and shear force by electromagnetically controlling the concentration of the fluid, and can realize a high-quality polishing process by excluding contact between the tool and the workpiece. An example of a magnetorheological fluid polishing system is disclosed in Korean Patent No. 0793409.

According to the above-described technique, a magnetorheological fluid and a polishing slurry are supplied on the periphery of the wheel member as a disk shape, a predetermined magnetic field is applied to the magnetorheological fluid and the polishing slurry, .

In such a polishing apparatus, since the magnetorheological fluid is separated from the wheel member by the centrifugal force of the wheel member, the rotational speed of the wheel member is limited.

In addition, although the wheel member has a predetermined diameter, since the periphery of the wheel member to which the object to be polished contacts is limited to a certain range, there is a problem that the area to be polished against the object to be polished is limited.

Further, since the magnetorheological fluid and the polishing slurry are supplied simultaneously, there is a problem that the magnetorheological fluid and the polishing slurry are mixed.

In order to solve the above problems, a polishing groove is formed on the polishing belt, a magnetorheological fluid and a polishing slurry are supplied separately, a magnetic field is applied on both sides of the polishing groove, and a glass edge is polished on the inside of the polishing groove An apparatus is disclosed.

FIG. 1 is a view showing an example of the configuration of a polishing groove and a magnetic field applying section of a polishing apparatus using a magnetorheological fluid according to a conventional technique, in which magnetic cores 20 Are arranged opposite to each other.

After the magnetorheological fluid and the polishing slurry are supplied into the polishing groove 11, the magnetic core 20 applies a magnetic field to the magnetorheological fluid.

When a magnetic field is applied, a uniform magnetic field is generated in the magnetic core 20.

2 is a graph showing the degree of magnetic field application on the abrasive belt corresponding to a and b in Fig.

1 and 2, the magnetic field application degree of the portion corresponding to the center (a) of the magnetic core 20 and the portion corresponding to the edge (b) of the magnetic core 20 in the polishing groove 11 It can be seen that there is a difference.

That is, since the magnetic field applied at the edge of the magnetic core 20 is applied together at the center a of the magnetic core 20, the degree of the magnetic field actually applied is large. However, the magnetic field is not applied to the edge b of the magnetic core 20. Therefore, when the glass edge is polished, the polishing is not uniformly performed.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and it is an object of the present invention to provide a magnetic abrasive belt, And an object of the present invention is to provide a glass edge polishing apparatus using a magnetorheological fluid.

According to an aspect of the present invention, there is provided a polishing apparatus comprising: an abrasive belt moving along a roller arranged up and down; A fluid supply unit for supplying and recovering the magnetorheological fluid with the abrasive belt; A magnetic field supply unit disposed apart from both sides of the abrasive belt for applying a magnetic field to the magnetorheological fluid supplied to the abrasive belt; And a polishing slurry supply unit supplying the polishing slurry to the polishing belt; Wherein the magnetic field supply unit is provided with a glass edge polishing apparatus using a magnetorheological fluid having a distance in the center of the opposing face being greater than a distance in the edge.

An abrasive groove having a sectional shape of '└┘' may be formed along the center of the abrasive belt.

The magnetic field supply unit includes a pair of magnetic poles which are connected to each other at one end and arranged parallel to each other on opposite sides of the abrasive belt, And a magnetic coil for generating a magnetic field applied through the magnetic core.

Wherein the fluid supply portion includes a fluid supply nozzle for supplying the magnetorheological fluid to the inside of the polishing groove and a fluid supplying nozzle for supplying the fluid for recovering the magnetorheological fluid used for polishing the glass edge inside the polishing groove, And a fluid circulation pump for circulating the magnetorheological fluid recovered through the fluid recovery nozzle to the fluid supply nozzle.

Wherein the polishing slurry supply unit comprises a polishing slurry supply nozzle for supplying the polishing slurry to the inside of the polishing groove, a polishing slurry collector disposed lower than the polishing slurry supply nozzle and for recovering the polishing slurry on the inside of the polishing groove, And a polishing slurry circulation pump circulating the polishing slurry collected by the polishing slurry collector to the polishing slurry supply nozzle.

The polishing slurry supply part may be arranged to be spaced apart from the belt than the fluid supply part.

In the present invention as described above, the separation distance of the magnetic field supply unit disposed on both sides of the polishing belt supplied with the magnetorheological fluid is made longer at the center than the edge of the opposing face, so that the magnetic field applied to the polishing belt becomes uniform as a whole.

1 is a view showing an example of the configuration of a polishing groove and a magnetic field applying section of a polishing apparatus using a magnetorheological fluid according to a conventional technique.
Fig. 2 is a graph showing the magnetic field strength on the abrasive belt corresponding to a and b in Fig. 1;
3 is a view showing an example of a configuration of a glass edge polishing apparatus using a magnetorheological fluid according to an embodiment of the present invention.
4 is a cross-sectional view taken along the line AA in Fig.
5 is a perspective view showing an example of the configuration of a magnetic field supply unit used in the present invention.
6 is a detailed view of a portion A in Fig.
7 is a graph showing the magnetic field strength on the abrasive belt corresponding to a and b in Fig.

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

3 is a view showing an example of a configuration of a glass edge polishing apparatus using a magnetorheological fluid according to an embodiment of the present invention.

Referring to FIG. 3, a glass edge polishing apparatus 100 using a magnetorheological fluid according to an embodiment of the present invention includes a polishing belt 110, a fluid supply unit 120, a magnetic field supply unit 130, a polishing slurry supply unit 140 ).

The abrasive belt 110 operates by driving the first and second rollers R1 and R2 arranged up and down. A motor is connected to the rotary shaft of the first and second rollers (R1, R2) so that the roller can be driven.

The abrasive belt 110 is entirely planar, but an abrasive groove 112 having a predetermined depth and width is formed along the middle portion of the abrasive belt 110. Here, the polishing belt 110 is arranged so that the polishing surface of the polishing groove 112 moves from the upper part to the lower part.

The abrasive belt 110 may comprise a material such as rubber or cloth.

Fig. 4 is a cross-sectional view taken along the line A-A in Fig. 3, showing an example of the configuration of the belt and magnetic field supply unit used in the present invention.

Referring to FIG. 4, the polishing groove 112 is formed to have a sectional shape of '?'. The polishing fluid is supplied to the polishing groove 112 and the polishing slurry to be described later, and the polishing operation is performed on the object 1 to be polished.

Here, the object to be polished 1 is a rectangular glass having a predetermined size, and one edge of the object 1 is inserted into the inside of the polishing groove 112 to perform polishing.

The width and the depth of the polishing groove 112 can be variously set according to the needs of the user.

Referring again to FIG.

The fluid supply part 120 supplies and retrieves the magnetorheological fluid to the inside of the polishing groove 112.

The fluid supply unit 120 includes a fluid supply nozzle 120A, a fluid recovery nozzle 120B, and a fluid circulation pump P1.

The fluid supply nozzle 120A supplies the magnetorheological fluid to the inside of the polishing groove 112. [

Magneto-rheological fluid (MR fluid) has the property that its viscosity changes when a magnetic field is applied.

A magnetorheological fluid is a fluid in which a nonmagnetic fluid such as oil or water is mixed with a magnetic material having a minute size that is sensitive to a magnetic field such as iron. The magnetic material included in the magnetorheological fluid has a diameter of several micrometers And is contained in a volume ratio of 30 to 40 percent. When a magnetic field is added to such a magnetorheological fluid, the flow characteristics are controlled in real time, and when a proper magnetic field is formed, the viscosity changes rapidly from the Newtonian fluid state to a strong semi-solid state, thereby increasing the viscosity and yield stress several times.

The fluid recovery nozzle 120B recovers the magnetorheological fluid used inside the polishing groove 112. The fluid recovery nozzle 120B is disposed lower than the fluid supply nozzle 120A. More specifically, the fluid recovery nozzle 120B is disposed lower than the object 1 to be polished.

The fluid circulation pump P1 supplies the magnetorheological fluid recovered through the fluid recovery nozzle 120B to the fluid supply nozzle 120A so that the magnetorheological fluid can be circulated and utilized.

The magnetic field supply unit 130 applies a magnetic field to the magnetorheological fluid 2 supplied to the polishing groove 112 so that the magnetorheological fluid 2 has a predetermined viscosity.

5 is a perspective view showing an example of the configuration of a magnetic field supply unit used in the present invention.

Referring to FIG. 5, the magnetic field supply unit 130 includes a pair of magnetic cores 132 and a magnetic coil 136.

The pair of magnetic cores 132 may have a predetermined length and width in a hexahedron shape, but the shape thereof may be variously formed according to the needs of the user. The pair of magnetic cores 132 are disposed opposite to each other on both sides of the polishing groove 112 formed on the polishing belt 110 to apply a magnetic field to the magnetorheological fluid 2 inside the polishing groove 112. And the other end is connected to a magnetic coil 136 described later.

The magnetic coil 136 generates a magnetic field applied through the magnetic core 132.

Here, the center of the opposing face of the magnetic core 132 may be formed to have a larger distance from the edge.

Fig. 6 is a detailed view of part A in Fig. 5, showing the configuration of the magnetic core 132 disposed on both sides of the abrasive belt 110 on which the polishing grooves 112 are formed.

The magnetic core 132 is disposed apart from both sides of the polishing groove 112 of the abrasive belt 110 and a plurality of protrusions protrudes on the opposing surfaces of the magnetic core 132.

A plurality of protrusions will be described in more detail.

The magnetic cores 132 are disposed opposite to each other at a certain distance from both sides of the polishing groove 112. Here, a plurality of protrusions protrude at regular intervals on the opposing surfaces of the magnetic core 132. [ 6, it is assumed that the number of protrusions is three. However, the number of protrusions may vary depending on the needs of the user. However, in the present embodiment, it is assumed that the number of protrusions is three. On the magnetic core 132, the protrusions are protruded to oppose each other.

The center projection is assumed to be the first projection 133a, and the projections on both side edges are assumed to be the second projection 133b.

Here, the first protrusion 133a and the second protrusion 133b may protrude at different heights. That is, as shown in the figure, the second projection 133b protrudes higher than the first projection 133a. When the number of the protrusions is three or more, it is preferable that the protrusion height of the protrusion gradually increases toward the edge from the center of the opposing face of the magnetic core 132.

The projecting height of the projections is made different from each other, so that there is a difference in the interval of the facing stone periods on the opposed faces of the magnetic core 132. [ That is, the distance between the first projections 133a is longer than the distance between the second projections 133b. Therefore, the magnetic field applied to the polishing groove 112 from the second projection 133b becomes larger than the magnetic field applied to the polishing groove 112 from the first projection 133a.

7 is a graph showing the magnetic field strength on the abrasive belt corresponding to a and b in Fig.

Referring to FIG. 7, it can be seen that a uniform magnetic field is applied regardless of a portion having a large separation distance and a portion having a small separation distance.

Referring again to FIG.

The polishing slurry supply unit 140 supplies the polishing slurry to the inside of the polishing groove 112. The polishing slurry is generally a liquid used in a polishing apparatus, and the polishing slurry contains abrasive grains.

The polishing slurry supply unit 140 is disposed apart from the belt 1100 more than the fluid supply unit 120.

The polishing slurry supply unit 140 includes a polishing slurry supply nozzle 142, a polishing slurry collector 144, and a polishing slurry circulation pump P2.

The polishing slurry supply nozzle 142 supplies the polishing slurry to the inside of the polishing groove 112. Here, the polishing slurry supply nozzle 142 is disposed on the abrasive belt 110 so as to be spaced apart from the fluid supply nozzle 120A. The polishing slurry supply portion of the polishing slurry supply nozzle 142 is preferably within a magnetic field application range of the magnetic field supply portion 130.

Therefore, the polishing slurry 3 supplied through the polishing slurry supply nozzle 142 is not mixed with the magnetorheological fluid 2 on the polishing groove 112, but is mixed with the magnetorheological fluid 2 and the object 1 So that the abrading object 1 is brought into contact with the abrading surface on the contact surface.

The polishing slurry collector 144 is a container having a predetermined size and is disposed directly below the operation surface of the polishing belt 110. [ The polishing slurry 3 used for polishing on the polishing grooves 112 is moved in the polishing grooves 112 to the polishing slurry collecting section 112. In this case, (144).

The polishing slurry circulation pump P2 circulates the polishing slurry 3 recovered in the polishing slurry collector 144 to the polishing slurry supply nozzle 142.

In the present invention, the magnetic field supply portions disposed on both sides of the abrasive belt supplied with the magnetorheological fluid have a larger separation distance from the center, so that the magnetic field applied to the abrasive belt becomes uniform as a whole.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

100: Glass edge polishing apparatus
110: abrasive belt 112: abrasive groove
120: fluid supply unit 130: magnetic field supply unit
140: polishing slurry supply part

Claims (6)

An abrasive belt moving along rollers arranged up and down and formed with an abrasion groove having a sectional shape of '?
A fluid supply unit for supplying and recovering the magnetorheological fluid with the abrasive belt;
A pair of magnetic cores, one end of which is opposed to and parallel to the opposite sides of the abrasive belt, and the other end of which has a lower height than that of the second projections protruding from the edge of the opposing face, A magnetic field supply unit including a magnetic coil for generating a magnetic field applied through the core and spaced apart from both sides of the abrasive belt to apply a magnetic field to the magnetorheological fluid supplied to the abrasive belt; And
A polishing slurry supply unit supplying the polishing slurry to the polishing belt; Lt; / RTI >
Wherein the magnetic field supply unit uses a magnetorheic fluid having a center distance of the opposing face being greater than a separation distance of the edge.
delete delete The method according to claim 1,
Wherein the fluid supply portion includes:
A fluid supply nozzle for supplying the magnetorheological fluid to the inside of the polishing groove,
A fluid recovery nozzle which is disposed lower than the fluid supply nozzle and recovers the magnetorheological fluid used for polishing the glass edge inside the polishing groove,
And a fluid circulation pump for circulating the magnetorheological fluid recovered through the fluid recovery nozzle to the fluid supply nozzle. The method according to claim 1 or 4,
The polishing slurry supply unit includes:
A polishing slurry supply nozzle for supplying the polishing slurry to the inside of the polishing groove,
A polishing slurry collector disposed lower than the polishing slurry feeding nozzle and recovering the polishing slurry inside the polishing groove,
And a polishing slurry circulation pump circulating the polishing slurry recovered by the polishing slurry recovery device to the polishing slurry supply nozzle. 6. The method of claim 5,
Wherein the polishing slurry supply unit is disposed apart from the belt more than the fluid supply unit.
KR1020150172320A 2015-12-04 2015-12-04 Glass edge grinding apparatus by using magneto-rheological fluids KR101763488B1 (en)

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KR101763488B1 true KR101763488B1 (en) 2017-07-31

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Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013530846A (en) * 2010-07-09 2013-08-01 コーニング インコーポレイテッド End finishing device

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013530846A (en) * 2010-07-09 2013-08-01 コーニング インコーポレイテッド End finishing device

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