Title:
Glass cassette for loading glass substrates of display panels
Kind Code:
A1


Abstract:
A glass cassette for loading glass substrates for display panels includes an upper plate, a lower plate, side plates, a stopper and stepped support members. The lower plate is disposed substantially parallel to the upper plate. The side plates are disposed spaced apart from each other in a first direction and substantially parallel to each other. The side plates are connected to the upper plate and the lower plate. The stopper is disposed at an end portion of the glass cassette to limit a movement of the glass substrates in a second direction that is substantially perpendicular to the first direction to stop the movement of the glass substrates upon insertion. The stopper is connected between the upper plate and the lower plate. The stepped support members are disposed at each of the side plates while facing each other in the first direction in order to flatly support the glass substrates.



Inventors:
Cho, Jae-nam (Asan-si, KR)
An, Geun-soo (Cheonan-si, KR)
Application Number:
11/316624
Publication Date:
10/12/2006
Filing Date:
12/12/2005
Primary Class:
International Classes:
A47G19/08
View Patent Images:
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Primary Examiner:
PUROL, SARAH L
Attorney, Agent or Firm:
CANTOR COLBURN LLP (Hartford, CT, US)
Claims:
What is claimed is:

1. A glass cassette for loading glass substrates of display panels, wherein the glass cassette comprises: an upper plate; a lower plate disposed substantially parallel to the upper plate; side plates disposed spaced apart from each other in a first direction and substantially parallel to each other, the side plates being connected to the upper plate and the lower plate; a stopper disposed at an end portion of the glass cassette to limit a movement of the glass substrates in a second direction that is substantially perpendicular to the first direction to stop the movement of the glass substrates upon insertion, the stopper being connected between the upper plate and the lower plate; and stepped support members disposed at each of the side plates while facing each other in the first direction in order to flatly support the glass substrates.

2. The glass cassette of claim 1, wherein the stepped support members comprise: a first stepped support member disposed at a first side plate; and a second stepped support member disposed at a second side plate corresponding to the first side plate such that the first and second stepped support members face each other, wherein a vertical distance between a step of the first stepped support member and the lower plate is substantially same as the vertical distance between a step of the second stepped support member, which faces the step of the first stepped support member, and the lower plate.

3. The glass cassette of claim 1, wherein a glass supporting surface is disposed on an external surface of the stepped support members and comes in contact with the glass substrate.

4. The glass cassette of claim 3, wherein the glass supporting surface includes a peak that extends in a direction perpendicular to a direction at which the glass substrates are inserted into the glass cassette.

5. The glass cassette of claim 1, wherein the stepped support member includes alternating glass supporting surfaces and vertical surfaces that are continuously connected to each other to form steps, and an inclined surface is disposed between each of the glass supporting surfaces and the vertical surfaces.

6. The glass cassette of claim 1, wherein the upper plate and the lower plate each have grooves extending along the first direction and facing each other, and a position of each of the side plates is adjustable along the grooves in order to adjust a spacing between the stepped support members responsive to a size of the glass substrates.

7. The glass cassette of claim 1, wherein the stepped support member comprises a metal portion.

8. A glass cassette for loading glass substrates of display panels, wherein the glass cassette comprises: an upper plate; a lower plate disposed substantially parallel to the upper plate; side plates disposed spaced apart from each other in a first direction and substantially parallel to each other, the side plates being connected to the upper plate and the lower plate; and support members disposed at each of the side plates while facing each other in the first direction in order to flatly support the glass substrates, wherein each of the support members comprises multiple glass supporting surfaces corresponding to glass substrates of varying sizes.

9. The glass cassette of claim 8, further comprising a stopper disposed at an end portion of the glass cassette to limit a movement of the glass substrates in a second direction that is substantially perpendicular to the first direction to stop the movement of the glass substrates upon insertion, the stopper being connected between the upper plate and the lower plate.

10. The glass cassette of claim 8, wherein a distance between the side plates is adjustable along grooves disposed in the upper and lower plates.

11. A glass cassette for loading glass substrates of display panels, wherein the glass cassette comprises: an upper plate; a lower plate disposed substantially parallel to the upper plate; side plates disposed spaced apart from each other in a first direction and substantially parallel to each other, the side plates being connected to the upper plate and the lower plate; a stopper disposed at an end portion of the glass cassette to limit a movement of the glass substrates in a second direction that is substantially perpendicular to the first direction to stop the movement of the glass substrates upon insertion, the stopper being connected between the upper plate and the lower plate; and stepped support members comprising a resin, the stepped support members disposed at each of the side plates while facing each other in the first direction in order to flatly support the glass substrates.

12. The glass cassette of claim 11, wherein the resin is a polyether ether ketone (PEEK).

13. The glass cassette of claim 11, wherein the stepped support member further comprises a metal portion.

14. The glass cassette of claim 11, wherein an external surface of the stepped support member that comes in contact with the glass substrates is made of the resin.

15. The glass cassette of claim 11, wherein the resin is a polyether ether ketone (PEEK).

16. The glass cassette of claim 13, wherein the metal portion is made of aluminum (Al).

17. The glass cassette of claim 13, wherein an external surface of the metal portion is stepped.

18. The glass cassette of claim 13, wherein the metal portion is integrally formed with one of the side plates.

19. A glass cassette for loading glass substrates of display panels, wherein the glass cassette comprises: an upper plate; a lower plate disposed substantially parallel to the upper plate; side plates disposed spaced apart from each other in a first direction and substantially parallel to each other, the side plates being connected to the upper plate and the lower plate; and support members comprising a resin disposed at each of the side plates while facing each other in the first direction in order to flatly support the glass substrates, wherein each of the support members comprises multiple glass supporting surfaces corresponding to glass substrates of varying sizes.

20. The glass cassette of claim 19, further comprising a stopper disposed at an end portion of the glass cassette to limit a movement of the glass substrates in a second direction that is substantially perpendicular to the first direction to stop the movement of the glass substrates upon insertion, the stopper being connected between the upper plate and the lower plate.

21. The glass cassette of claim 19, wherein a distance between the side plates is adjustable along grooves disposed in the upper and lower plates.

22. The glass cassette of claim 19, wherein the support members further comprise a metal portion, and the resin is disposed at a surface of the support members that contact the glass substrates.

Description:

This application claims priority to Korean Utility Model Application No. 2005-0009634 filed on Apr. 8, 2005 and Korean Patent Application No. 2005-0037084 filed on May 3, 2005, and all the benefits accruing therefrom under 35 U.S.C ยง119, and the contents of which in its entirety are herein incorporated by reference.

BACKGROUND OF THE INVENTION

(a) Field of the Invention

The present invention relates to a glass cassette for loading glass substrates of display panels, and more particularly, to a glass cassette for loading glass substrates having various sizes.

(b) Description of the Related Art

Recent developments in semiconductor technology have led to a demand for display devices having smaller size, decreased weight and enhanced performance. Liquid crystal display (LCD) devices, plasma display panel (PDP) devices, flat emission display (FED) devices, vacuum fluorescent display (VFD) devices, and organic light emitting display (OLED) devices are examples of such display devices.

Although display devices are manufactured by various methods, most of the display devices include a pair of glass substrates with a vacuum between the pair of glass substrates. Glass substrates are typically produced by cutting an original piece of glass into a plurality of cell glass substrates, which are used in manufacturing display devices.

The original piece of glass or the cell glass substrates are loaded into a glass cassette in order for transportation during a manufacturing process. For example, during manufacture of an LCD device, multilayered thin film patterns are disposed on transparent insulation glass panels or cell glass substrates made of, for example, SiO2 using a deposition process and an etching process. Next, the cell glass substrates are loaded into the glass cassette and transported in order to undertake a next process. Since the cell glass substrate is suctioned and attached to an arm of a robot, it is possible to remove the cell glass substrate from the glass cassette freely. Additionally, since the cell glass substrate is transported in the glass cassette, exposed surfaces of the cell glass substrate may be protected from damage, and thereby the cell glass substrate is both preserved and easily transported.

Recently, large display devices have been manufactured using a large cell glass substrate. The large cell glass substrate is manufactured by cutting large pieces of original glass using a multi-cutting process. When the large cell glass substrate is manufactured, it is necessary for the large cell glass substrate to be loaded into the glass cassette without deflection. When the large cell glass substrate is deflected, patterns disposed on a surface of the large cell glass substrate may be damaged or the large cell glass substrate may be broken. In addition, when the large cell glass substrate is deflected while being loaded in the glass cassette, it is difficult to stably fix the large cell glass substrate in the glass cassette.

Additionally, a problem currently exists in that cell glass substrates of various sizes cannot be loaded together into a glass cassette of the prior art. Since each glass cassette currently loads cell glass substrates of only one size, many glass cassettes are required to transport each of various different sizes of glass substrates. Therefore, a cost of manufacturing display devices is increased.

SUMMARY OF THE INVENTION

The present invention is contrived to solve the above-mentioned problems by providing a glass cassette for loading glass substrates of various sizes together.

A glass cassette for loading glass substrates of display panels includes an upper plate, a lower plate, side plates, a stopper and stepped support members. The lower plate is disposed substantially parallel to the upper plate. The side plates are disposed spaced apart from each other in a first direction and substantially parallel to each other. The side plates are connected to the upper plate and the lower plate. The stopper is disposed at an end portion of the glass cassette to limit a movement of the glass substrates in a second direction that is substantially perpendicular to the first direction to stop the movement of the glass substrates upon insertion. The stopper is connected between the upper plate and the lower plate. The stepped support members are disposed at each of the side plates while facing each other in the first direction in order to flatly support the glass substrates.

In another exemplary embodiment of the present invention, a glass cassette for loading glass substrates of display panels includes an upper plate, a lower plate, side plates, and stepped support members including a resin. The lower plate is disposed substantially parallel to the upper plate. The side plates are disposed spaced apart from each other in a first direction and substantially parallel to each other. The side plates are connected to the upper plate and the lower plate. The stepped support members including a resin are disposed at each of the side plates while facing each other in the first direction in order to flatly support the glass substrates. Each of the support members includes multiple glass supporting surfaces corresponding to glass substrates of various sizes.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings, in which:

FIG. 1 is a perspective view of a glass cassette according to an exemplary embodiment of the present invention;

FIG. 2 is a front view of the glass cassette of FIG. 1;

FIG. 3 is an enlarged view of area A of FIG. 1;

FIG. 4 is an enlarged view of area B of FIG. 1; and

FIG. 5 is an enlarged view of a stepped supporting member of a glass cassette according to an exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to FIGS. 1 to 5. The embodiments herein explained are intended only to exemplify the present invention, and thus the present invention is not limited thereto.

FIG. 1 shows a glass cassette 100 for loading glass substrates of various sizes. For example, as shown in FIG. 1, a size of a relatively large glass substrate G1 is larger than a size of a relatively small glass substrate G2. A structure of the glass cassette 100 shown in FIG. 1 is merely to illustrate an exemplary embodiment of the present invention and the present invention is not limited thereto. Accordingly, the structure of the glass cassette 100 may be modified into other forms.

A shape of the glass cassette 100 shown in FIG. 1 is similar to a hexahedron. The glass cassette 100 includes side plates 24 that are installed to face each other. The side plates 24 are extended in a Y-axis direction and arranged in an X-axis direction, which is substantially perpendicular to the Y-axis direction, such that each of the side plates 24 is substantially parallel to each other and faces each other. The side plates 24 are spaced apart from each other along the X-axis direction by a selected distance. The side plates 24 are extended in a Z-axis direction, which is substantially perpendicular to an X-Y plane. In order to load as many glass substrates into the glass cassette 100 as possible, it is desirable that the glass substrates are loaded in the Y-axis direction. In order for a glass handling robot to conveniently handle the glass substrates and in order to occupy an effective processing space in a production line, it is desirable that accommodation for size differences between the glass substrates should be made in the X-axis direction rather than in the Z-axis direction. Therefore, the side plates 24 are installed along the X-axis direction such that the glass cassette 100 may accommodate glass substrates having different sizes.

It is possible to adjust a spacing between the side plates 24 along the X-axis direction by moving the side plates 24, as described below. Therefore, the relatively small glass substrate G1 can be loaded into a space between one set of side plates 24, while the relatively large glass substrate G2 can be loaded into a space between another set of side plates 24. Alternatively, the relatively small and large glass substrates G1 and G2 may both be loaded between a same set of side plates 24 because the glass cassette 100 includes support members capable of accommodating glass substrates having various sizes. Advantageously, occupying efficiency of space within the glass cassette 100 may be improved.

Referring to FIG. 1, the glass cassette 100 includes an upper plate 21, a lower plate 22, the side plates 24, and a stopper 23. The glass cassette 100 may also include other elements, if necessary. The glass substrates may be inserted into the glass cassette 100 or removed from the glass cassette 100 in a direction indicated by an arrow (in the Y-axis direction). The stopper 23 is installed at an interior portion of the glass cassette 100 such that the stopper 23 limits motion of the glass substrates G1 and G2 in the Y-axis direction in order to stop them upon insertion. The stopper 23 extends in the Z-axis direction, for example, from the lower plate 22 to the upper plate 21. Therefore, the stopper 23 prevents the glass substrates from falling out of the glass cassette 100.

The stopper 23 in FIG. 1 is shown substantially in a vertical orientation along the Z-axis, but alternatively, the stopper 23 may be placed diagonally from the lower plate to the upper plate 21. In other alternative embodiments, a single stopper 23 or more than two may be installed on the interior portion of the glass cassette 100 such that that movement of the glass substrates G1 and G2 in the Y-axis may be limited.

The lower plate 22 is disposed substantially parallel to the upper plate 21 and faces the upper plate 21. Rollers 30 may be installed under the lower plate 22 to permit movement of the glass cassette 100. The side plates 24 connect the upper plate 21 and the lower plate 22 together and face each other. A plurality of stepped support members 15 may be installed on each of the side plates 24 to have a predetermined spacing between each of the stepped support members 15 in both the Y-axis and Z-axis directions. Each of the stepped support members 15 extends toward a corresponding one of the stepped support members 15 disposed at a corresponding one of the side plates 24.

The stepped support members 15 may be individually installed on the side plates 24. The side plates 24 may be configured to allow the support members 15 to be installed at any of a number of positions along the side plates 24. In alternative embodiments, the stepped support members 15 may be pre-assembled onto a strip (not shown), the strip with the support members 15 then installed on the side plates.

Glass substrates of various sizes may be loaded into the glass cassette 100 together due to a structure of the stepped support members 15. In other words, as shown in FIG. 1, it is possible to load the relatively large glass substrate G1 and the relatively small glass substrate G2 into the glass cassette 100 together.

Referring to FIG. 1, the upper plate 21 and the lower plate 22 may have top and bottom grooves 211 and 213, respectively. The top and bottom grooves 211 and 213 face each other along the Z-axis direction and are formed along the X-axis direction. The side plates 24 are installed to enable movement of the side plates 24 along the grooves 211 and 213 in the X-axis direction. For example, the side plates 24 can be freely moved in the X-axis direction by releasing screws 241. The screws 241 are screwed into a hole (not shown) which is continuously formed through screw fixing members 243 and the side plates 24. When the side plates 24 are placed in a desirable position, is the side plates 24 are fixed there by tightening the screws 241. Therefore, it is possible to adjust spacing between stepped support members 15 facing each other according to a size of the glass substrates.

The screw fixing members 243 can be detached from the side plates 24 by completely unscrewing the screws 241 if necessary. Therefore, the side plates 24 may be easily removed from the glass cassette 100. Removal of the side plates 24 may be necessary when a spacing between the side plates 24 and stepped support members 15 must be adjusted in order to load a much larger glass substrate. Advantageously, the glass cassette 100 is easily maneuverable and configurable to enhance a transporting capability of glass substrates so that manufacturing time is reduced since the side plates 24 can be easily detached from the glass cassette 100 or repositioned.

As shown in FIG. 2, the glass substrates G1 and G2, which are inserted into the glass cassette 100, are flatly supported in the X-Y plane or horizontal direction. The stepped support members 15 are formed to face each other in the horizontal direction so as to flatly support the glass substrates. Advantageously, it is also possible to prevent deflection of the glass substrates such that patterns formed on the glass substrates are not damaged.

The stepped support members 15 include a first stepped support member 15a and a second stepped support member 15b facing the first stepped support member 15a. The glass substrate (G1 for example) may be loaded onto corresponding steps of the first stepped support member 15a and the second stepped support member 15b. In an exemplary embodiment of the present invention, heights of the steps of the first and second stepped support members 15a and 15b facing each other may be substantially the same in order to flatly support the relatively large and small glass substrates G1 and G2.

For example, a vertical distance h1 between a step 151a of the first stepped support member 15a and the lower plate 22 is substantially same as a vertical distance h2 between a corresponding step 151b of the second stepped support member 15b, which faces to the step 151a of the first stepped support member 15a, and the lower plate 22. Therefore, it is possible to load a glass substrate into the glass cassette 100 stably.

In alternative embodiments, the heights of the steps of the first and second stepped support members 15a and 15b may be different as to support the glass substrates G1 and G2 at an angle as retrieval or placement of the glass substrates G1 and G2 into the glass cassette 100 may require.

An enlarged view of area A of FIG. 1 showing the stepped support member 15 is shown in FIG. 3. The stepped support member 15 has a structure capable of supporting various sizes of glass substrates without changing a position of the side plates 24. The shape of the stepped support member 15 shown in FIG. 3 is merely to illustrate an exemplary embodiment of the present invention, and the present invention is not limited thereto.

An external surface of the stepped support member 15 is shaped like steps which include alternating glass supporting surfaces 1531 and vertical surfaces 1533 which are continuously connected to each other. In other words, the external surface of the stepped support member 15 includes a series of alternating vertical surfaces 1533 and glass supporting surfaces 1531, which form a series of steps. Although three such steps are shown in FIG. 3, a number of the steps may be more or less than three as desired. Therefore, a glass substrate may be loaded into or removed from the glass cassette 100 by a robot or an operator and the glass substrate is effectively supported while taking up minimal space in the glass cassette 100. Advantageously, the glass substrate may be prevented from being cracked and a generation of particulates is prevented by reducing contact or interference with the vertical surface 1533 of the stepped support member 15.

In an exemplary embodiment, the stepped support member 15 is made of a resin, which is substantially non-abrasive and provides stability for the glass substrate when the glass substrate is placed on the stepped support member 15 and comes in contact therewith. Advantageously, the glass substrate is prevented from being scratched.

Glass substrates undergo a thermal treating process while in the glass cassette 100. Therefore, there is a possibility that the stepped support member 15 may be thermally deformed if a general resin is used to form the stepped support member 15. Thus, polyether ether ketone (PEEK), which is resistant to thermal deformation, is used as the resin in the stepped support member 15.

A peak 1531a may be formed on the external surface of the stepped support member 15, which comes in contact with the glass substrate. A shape of the peak 1531a in FIG. 3 is merely to illustrate an exemplary embodiment of the present invention and the present invention is not limited thereto. Therefore, the shape of the peak 1531a can be modified to other forms. Advantageously, the peak 1531a minimizes friction between the glass substrate and the stepped support member 15 to prevent scratches on a surface of the glass substrate by minimizing a contact area between the glass substrate and the stepped support member 15. This will be explained in more detail with reference to FIG. 4 below.

An inclined surface 1535 may be formed between the glass supporting surface 1531 and the vertical surface 1533 of the stepped support member 15. The inclined surface 1535 advantageously reduces interference between the glass substrate and the vertical surface 1533 of the stepped support member 15, and makes it easier to load the glass substrate into the glass cassette 100.

FIG. 4 is an enlarged view showing the stepped support member 15 of area B of FIG. 1. The relatively larger glass substrate G1 is loaded onto the stepped support member 15. The glass supporting surface 1531 is peaked along the X-axis direction substantially perpendicular to the glass-inserting direction (the direction indicated by an arrow in the y-direction). In other words, the peak 1531a of each glass supporting surface 1531 extends in the X-axis direction, which is substantially perpendicular to the glass-inserting direction.

An enlarged circle of FIG. 4 shows a cross section of a portion of the relatively large glass substrate G1 and the stepped support member 15. As shown in FIG. 4, a contact area between the relatively large glass substrate G1 and the glass supporting surface 1531 on which the relatively large glass substrate G1 is loaded is minimized. In other words, the relatively large glass substrate G1 only comes in contact with the peak 1531a of the stepped support member 15. In particular, the glass supporting surface 1531 is shaped with inclined surfaces that form the peak 1531a. Therefore, particulates do not remain on the glass supporting surface 1531 but rather fall off. Advantageously, since the particulates are removed in this manner, deterioration of quality of a glass substrate due to the particulates is reduced, or effectively prevented.

FIG. 5 shows a stepped support member 25 provided in the glass cassette 100 according to another exemplary embodiment of the present invention. Since a structure of the stepped support member 25 is substantially same as the stepped support member 15 described with reference to FIGS. 1-4, a detailed explanation of the same elements will be omitted for convenience.

As shown in FIG. 5, a metal portion 251 is included in the stepped support member 25. An external surface of the metal portion 251 is covered with a resin 253. Since a forming process of the resin 253 on the external surface of the metal portion 251 can be easily understood by those skilled in the art, a detailed explanation of the forming process is omitted.

It is possible to easily injection-mold the resin 253 on the external surface of the metal portion 251. Strength of the metal portion 251 allows a length of the stepped support member 25 to be increased in order to stably support a large glass substrate. In such a case, if the stepped support member 25 is manufactured using the metal portion 251, the resin 253 does not sink while being injection-molded.

Since the stepped support member 25 is extended in the X-axis direction, it is pressed downward (Z-axis direction) when the large glass substrate is loaded thereon. Accordingly, unless it is strong enough, the stepped support member 25 can be deflected downward and the large glass substrate may fall off. Advantageously, strength of the stepped support member 25 is improved by using the metal portion 251, which reduces, or effectively prevents deflection of the stepped support member 25.

In an exemplary embodiment, a light material with good strength such as Al is used as the metal portion 251, although other light materials may also be used. The metal portion 251 may be integrally manufactured with the side plate 24 and then injection-molded with the resin 253.

In addition, an upper surface 2511 of the metal portion 251 is stepped, thereby reinforcing the strength of the stepped support member 25, while allowing multiple sized glass substrates to be transported by the glass cassette 100 without requiring a repositioning of the side plates 24. Although the upper surface 2511 of the metal portion 251 is stepped in FIG. 5, this is merely to illustrate an exemplary embodiment of the present invention and the present invention is not limited thereto. Therefore, it is satisfactory if at least one external surface among the external surfaces of the metal portion 251 is stepped.

Direct contact between a glass substrate and the metal portion 251 may cause damage to the glass substrate. In order to prevent damage to the glass substrate, at least one external surface of the stepped support member 25 that comes in contact with the glass substrate may be made of or coated with the resin 253.

In a glass cassette according to an exemplary embodiment of the present invention, stepped support members are installed in the horizontal direction while facing each other. Advantageously, damage to the glass substrate caused by deflection thereof can be reduced, or effectively prevented.

Since a vertical distance between a step of a first stepped support member and a lower plate of the glass cassette may be substantially the same as a vertical distance between a corresponding step of a second stepped support member and the lower plate, the glass substrate may be stably loaded in the glass cassette.

A peak may be formed on an external surface of the stepped support members and comes in contact with the glass substrate to minimize a contact area between the glass substrate and the stepped support member and reduce, or effectively prevent scratches or damage to a surface of the glass substrate.

Inclined surfaces are formed between the glass supporting surface and a vertical surface of the stepped support member, and thereby interference between the glass substrate and the vertical surface of the stepped support member can be minimized. Therefore, it is easy to load the glass substrate into the glass cassette.

Since grooves are formed in an upper plate and lower plate of the glass cassette, it is possible for spacing between side plates facing each other to be varied. Since the stepped support members are made of a resin, the glass substrate is prevented from being damaged. Since PEEK is used as the resin, thermal deformation of the stepped support members is prevented. A metal portion may be included in the stepped support member, thus strength of the stepped support member is reinforced.

Although exemplary embodiments of the present invention have been described, it can be obviously understood by those skilled in the art that the present invention may be modified in various forms without departing from the spirit and scope of the appended claims.