JP2013514259A - Separation of glass sheets from laser-marked curved glass ribbons - Google Patents

Abstract

A method and apparatus for separating a glass sheet (13) from a laser-scribed curved glass ribbon (33) is disclosed. In a particular embodiment, the glass ribbon (33) is flattened before the separation between the glass sheet (13) and the ribbon (33) begins at the position of the laser-marked scribe line (7). By making reliable contact with (540), the occurrence of edge defects is reduced. In other embodiments, the nosing (540) has a circular cross-section and is optionally rotatable. In a further embodiment, the nosing is integrated with the sheet engaging assembly (530), and the nosing moves further away from the newly formed upper edge (690) of the glass sheet (13), thereby continuing the processing station. It is assumed that the upper part of the sheet (13) can be engaged for movement to the position.

Description

Explanation of related applications

  This application claims the benefit of priority of US Provisional Patent Application No. 61 / 286,961, filed Dec. 16, 2009.

  The present disclosure relates to a method and apparatus for separating a glass sheet from a laser-scribed curved glass ribbon.

  The following discussion refers to a vertically moving glass ribbon, which is a typical application of the method and apparatus disclosed herein. However, this orientation is only assumed to aid this announcement and should not be construed as limiting the present disclosure in any way.

Glass scoring is conventionally performed using mechanical means. However, for example, by heating the glass using laser radiation, such as CO ₂ laser radiation with a wavelength of 10.6 [mu] m, there are alternative means for generating a tensile stress by a temperature gradient. Regarding those using a laser for scoring glass, Patent Document 1 entitled “Method and apparatus for breaking brittle materials” by the same applicant and “In laser scoring” This is discussed in US Pat. No. 6,057,096 entitled “Control of median crack depth in laser scoring”.

  As shown in FIG. 1, during laser scoring, a vent is generated on the main surface 114 of the glass 112 along the line 115. To create a vent, a small scratch start point 111 is formed near one edge on the glass surface. In order to transform the scratch start point into a vent, the laser beam 121 generated by the laser 141 is propagated so that the footprint 113 traverses the glass surface, and the cooling area generated by the cooling nozzle 119 is added to this. Follow. Heating the glass with a laser light beam and then quenching it immediately with a coolant creates a thermal gradient and a corresponding stress field, which contributes to the propagation of the scratch start and vents. Form.

  Patent document 3 (published '994) by the same applicant describes a laser scoring system for a moving glass ribbon. In this system, the moving carriage moves along a linear trajectory that is inclined by an angle α with respect to a line crossing the direction of ribbon movement.

Figures 2 and 3 of the present application schematically illustrate the '994 published system. In these figures, the reference number 33 for the glass ribbon, the number 14 for the moving carriage, the number 15 for the linear track, the number 11 for the support structure (support frame) for the track, and the equipment for generating the ribbon, such as a fusion draw device, It is identified by the number 9. As discussed in the '994 publication, when viewed from a fixed reference frame (eg, the xyz reference frame of FIG. 2), the glass ribbon moves at a speed S _ribbon in the direction of vector 16 and the carriage is It moves at a speed S _carriage in the direction of the vector 17. Here, S _ribbon , S _carriage , and angle α satisfy the following relationship.

S _carriage = S _ribbon / sin α equation (1)
Thus, the carriage keeps the same pace as the ribbon, ie, more precisely, the magnitude of the component parallel to the direction of ribbon movement at the carriage speed is equal to S _ribbon . As a result, when viewed from the ribbon, the carriage simply traverses the ribbon in the direction of the vector 18, ie along the crease line 7 perpendicular to the direction of movement of the ribbon, and the speed S _score given by Move with.

S _score = S _carriage cosα equation (2)
As described in the '994 publication, a light emitting device that provides a laser light beam and a nozzle that provides a cooling fluid flow (e.g., water) are coupled to the carriage, and when the carriage moves along a linear trajectory, Together these form a vent across the width of the ribbon. In some embodiments, a mechanical scoring head (eg, a scoring wheel) is further coupled to the carriage to form a scratch start point on the glass ribbon. Alternatively, the scratch start point may be formed by equipment other than the carriage.

  FIG. 4 schematically illustrates these aspects of the '994 publication. Reference numerals 21, 22, and 23 denote the positions of (1) the cooling fluid footprint, (2) the laser light beam footprint, and (3) the scratch start point at the start of the scoring process. The reference numbers 31 and 32 represent the positions of the cooling fluid footprint and the laser light beam footprint at some point after completion of the start.

US Pat. No. 5,776,220 US Pat. No. 6,327,875 US Patent Application Publication No. 2008/0264994

  Regarding the cutting of individual glass sheets 13 from the ribbon 33, the '994 publication refers to using conventional bending techniques. In this technique, a robot with a suction cup grips the glass ribbon below the scribe line, and the robot also bends the ribbon to separate the ribbon at the scribe line. According to the present disclosure (see below), it has already been found that scoring lines generated by a laser have different characteristics than scoring lines generated by a mechanical scoring device. . As a result, bending techniques that have historically worked well for mechanically scribed ribbons have poor quality edges for laser scribed ribbons, such as edges with jagged cracks. Is known to bring As is well known in the art, inferior edges can lead to sheet breakage and, in turn, can result in a large amount of chips in the subsequent handling and finishing process. The present disclosure addresses this issue and when separating a glass sheet from a laser-marked ribbon using a bending technique, the edge quality of the sheet is at least substantially equivalent to that obtained by mechanical scoring. A method and apparatus are provided.

According to a first aspect, a method of making a glass sheet (13) is disclosed, the method comprising:
(I) forming a glass ribbon (33) having a first surface (501) and a second surface (502); and
(II) forming a plurality of glass sheets (13) from the ribbon (33), the process of producing each glass sheet (13) comprising:
(A) forming a ruled line (7) using a laser (141) on the first surface (501) of the glass ribbon (33); and
(B) separating the glass sheet (13) from the glass ribbon (33) at the scribing line (7), and this separation process comprises a bending moment at the scoring line (7) on the laser-marked glass. Rotating the sheet engaging assembly (530) about an axis through the scoring line (7) so that the sheet engaging assembly (530) is in the frame (520). And a plurality of ribbon / sheet holding devices (eg, suction cups (510)) that engage at least a second surface (502) of the glass ribbon (33) and are supported by the frame (520). The distance between the scribing line (7) and the ribbon / sheet holding device closest to the scribing line (7) is L,
here,
(I) During step (II) (B), a nosing (540) that is flat in the direction across the ribbon engages the second surface (502) of the ribbon (33) at the score line (7). And then
(Ii) The second side (502) of the ribbon (33) is moved to the ribbon (33) before any separation of the glass sheet (13) from the glass ribbon (33) occurs by rotation of step (II) (B). L is chosen to be sufficiently long so that it contacts the nosing (540) over substantially the entire width.

According to a second aspect, a method for improving the edge quality of a glass sheet (13) is disclosed, and the process of making this glass sheet comprises:
(I) forming a glass ribbon (33) having a first surface (501) and a second surface (502); and
(II) forming a plurality of glass sheets (13) from the ribbon (33), the process of producing each glass sheet (13) comprising:
(A) forming a ruled line (7) using a laser (141) on the first surface (501) of the glass ribbon (33); and
(B) separating the glass sheet (13) from the glass ribbon (33) at the scoring line (7), the separation process comprising:
A sheet engagement assembly (530) about an axis passing through the scoring line (7), with a nosing (540) that is flat in the direction across the ribbon contacting the second surface (502) of the glass ribbon (33). The step of rotating,
Wherein the seat engaging assembly (530) engages the frame (520) and at least the second surface (502) of the glass ribbon (33) during rotation and the frame (520). And a plurality of ribbon / sheet holding devices (for example, a suction cup (510)), and the ribbon / sheet holding device closest to the scribe line (7). The distance between and is L
The method includes the step of increasing L from a reference value suitable for mechanical scoring so as to improve the edge quality of the glass sheet (13) separated from the ribbon (33). .

According to a third aspect, a method of making a glass sheet (13) is disclosed, which method comprises:
(I) forming a glass ribbon (33) having a first surface (501) and a second surface (502); and
(II) forming a plurality of glass sheets (13) from the ribbon (33), the process of producing each glass sheet (13) comprising:
(A) forming a ruled line (7) using a laser (141) on the first surface (501) of the glass ribbon (33); and
(B) separating the glass sheet (13) from the glass ribbon (33) at the scribing line (7), and this separation process comprises a bending moment at the scoring line (7) on the laser-marked glass. Rotating the sheet engaging assembly (530) about an axis through the scoring line (7) so that the sheet engaging assembly (530) is in the frame (520). And a plurality of ribbon / sheet holding devices (eg, suction cups (510)) that engage at least a second surface (502) of the glass ribbon (33) and are supported by the frame (520). And
here,
(I) During step (II), the nosing (540) supported on the frame (520) engages the second surface (502) of the ribbon (33) at the ruled line (7);
(Ii) After step (II), the method moves the nosing (540) away from the separated glass sheet (13) to expose the upper edge (690) of the sheet (13). It is characterized by including.

  An apparatus for performing the above method is further disclosed.

  The reference numbers used in the above summary of various aspects of the disclosure are for the convenience of the reader only and are not intended to be construed as limiting the scope of the invention. Should not be done. More generally, the foregoing general description and the following detailed description are merely exemplary of the invention and are intended to provide an overview or arrangement for understanding the nature and features of the invention. I want you to understand.

  Additional features and advantages of the invention will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from the description or may be described by way of example in the present description. It will be recognized by doing. The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. It should be understood that the various features of the invention disclosed in this document and in the drawings can be used in any and all combinations. Exemplary combinations of specific features are specified below as additional aspects of the invention.

  According to a fourth aspect, there is provided a method according to any one of the first to third aspects, characterized in that nosing is supported by the frame.

  According to a fifth aspect, there is provided a method according to any one of the first to fourth aspects, characterized in that the nosing has a curved cross section.

  According to a sixth aspect, there is provided a method according to any one of the first to fifth aspects, characterized in that the nosing has a circular cross section.

  According to a seventh aspect, there is provided a method according to any one of the first to sixth aspects, characterized in that nosing is rotatable about an axis parallel to the scribing line.

  According to an eighth aspect, there is provided the method of any one of the first to seventh aspects, characterized in that the glass ribbon is formed by a downdraw process.

  According to a ninth aspect, there is provided the method of any one of the first to eighth aspects, characterized in that the glass sheet is a substrate for a display device.

  According to the tenth aspect, the second aspect or the fourth to ninth aspects are characterized in that the frame is operated by a robot and L is increased by changing one or more operation parameters of the robot. Any one of the methods is provided.

  According to an eleventh aspect of the first to tenth aspects, further comprising engaging the exposed top of the separated sheet and further moving the sheet to a subsequent processing station Any one method is provided.

  According to the twelfth aspect, the ribbon / sheet holding device includes a pad for engaging the first surface of the ribbon and a suction cup for engaging the second surface, and A method according to any one of the first to eleventh aspects is provided, comprising the step of engaging a ribbon with a suction cup using a pad.

  According to a thirteenth aspect, there is provided a method according to any one of the first to twelfth aspects, characterized in that the nosing is flat in the direction across the ribbon.

Schematic showing laser scoring Schematic showing the laser marking system by '994 release Schematic showing in more detail the movement of the carriage of FIG. Schematic showing the position of the cooling fluid, laser light beam, and scratch start point at the beginning of the scoring process and after a while Schematic showing the seat engaging assembly and nosing engaging the curved ribbon Schematic view of the seat engagement assembly, nosing, and curved ribbon of FIG. 5 viewed from above. Schematic showing the rotation of the glass ribbon, generating a bending moment at the position of the crease line Effect of changing the distance between the scoring line and the ribbon / sheet holding device (specifically, in this case, the closest suction cup) of the sheet engagement assembly closest to this line Plot of calculated data showing FIG. 5 is a schematic view of the seat engagement assembly, nosing, and curved ribbon of FIG. 5 viewed from above after the ribbon has been rotated as shown in FIG. Schematic showing nosing with a curved cross section A perspective view of an integrated nosing / seat handling assembly prior to engagement with a glass ribbon A perspective view of the integrated nosing / seat handling assembly after engaging the glass ribbon A perspective view of the integrated nosing / sheet handling assembly immediately after separating the glass sheet from the glass ribbon. A perspective view of the integrated nosing / sheet handling assembly after the robot has moved the assembly and the separated glass sheet attached thereto away from the glass ribbon. The robot moves the assembly and the separated glass sheet attached to it away from the glass ribbon, and the robot moves the assembly to the sheet so that the handling equipment can engage the sheet from above. A perspective view of the integrated nosing / seat handling assembly after moving away from the upper edge Side view showing in more detail the nosing of FIGS.

  As noted above, the present disclosure relates to the discovery that crease lines generated by laser crease have different separation characteristics than crease lines produced by mechanical scribers. That is, when the mechanical scoring device generates a scoring line, the device physically moves the glass surface and the glass below the glass surface at the position of the scoring line. This process produces a large number of glass particles, many of which may be found embedded in the glass at or near the scribe line. As a result, if the mechanically scribed glass can be left as it is, it is often separated spontaneously at the mechanical scribe line without applying bending force. That is, mechanical scoring as a result of the physical damage that the glass has received so far, or the stress induced by particles forced into the glass at the scoring line position by a mechanical scoring device. Scraped glass separates spontaneously.

  The ruled lines formed by the laser are quite different. First, the laser typically does not move the glass material off the scoring line and does not generate particles that will be embedded in the glass at and near the scoring line. Rather, the laser is affected by weakening chemical bonds at the location where the laser and cooling fluid acted. If it is allowed to be left as it is, especially in a humid atmosphere where water can be involved in chemical bond restructuring, the laser scribed lines are actually separated rather than separated spontaneously. May be repaired. As a result, it has already been found that a glass sheet separated by a scribing line laser-marked from a glass ribbon is significantly different from a glass sheet separated by a mechanical scoring line.

  In particular, for glass ribbons that are curved when undergoing the sheet separation process, the glass bending procedure that has historically worked well on mechanically scored crease lines is subject to all other conditions. It has been found that edges of inferior quality are produced when applied to laser marked scribe lines with the same. In fact, it has already been found that this edge quality is so poor that the majority of the resulting sheet is useless for its intended purpose, for example a liquid crystal display substrate.

  According to one aspect of the present disclosure, by changing the bending process so that separation at this scoring line does not begin until the portion of the glass ribbon that contains the laser-scribing scoring line is substantially flat. Overcoming the problem of not being able to use conventional bending techniques for laser marked scribe lines. In practice, in particular where the glass scoring and separation takes place (often referred to as the “bottom of the draw” or BOD (bottom of the draw)), in particular, the thickness is 0.7 mm or less and For example, in a ribbon made of thin glass having a width as wide as 0.5 m or more, the glass ribbon has a non-flat shape in a direction transverse to stretching. For example, the ribbon may be arcuate and either side of the ribbon may be concave. For example, it may be a more complicated shape such as an M shape or a W shape.

  FIGS. 5 and 6 show an example of an arcuate ribbon 33, where the concave surface of the ribbon faces the suction cup 510 and frame 520 of the seat engagement assembly 530. As shown in these figures, suction cup 510 engages second surface 502 of ribbon 33 and nosing 540 engages as well. Although suction cups are shown as ribbon / sheet holding devices in FIGS. 5 and 6, it will be appreciated that the holding device may have various other structures now known or later developed in the art. I want you to understand. For example, as shown in FIGS. 11 to 15, the holding device may include a pad that engages with the first surface 501 of the ribbon and a suction cup that engages with the second surface. As another variation, the suction cup of FIGS. 11-15 that engages the second side of the ribbon may be replaced with a pad so that the ribbon is clamped between a set of pads that engage its opposing side. Become.

  As shown in FIG. 7, during the separation process, for example, using an industrial robot 700, the sheet engaging assembly 530 is moved around the axis through the scoring line and the nosing 540 is a stop or fulcrum of rotation. Rotate to function as. In addition to this figure, in FIGS. 5 and 6, the laser-marked scribe line is provided on the first side 501 of the ribbon, ie, the side away from the nosing 540, and the frame and ribbon / sheet. The rotation of the holding device (suction cup in this embodiment) is clockwise. As can be seen from FIG. 6, since the ribbon is not flat, a gap 560 exists between the nosing 540 and the second surface 502 of the ribbon.

  By rotating the sheet engaging assembly 530, a bending moment is applied to the glass ribbon at the score line. When this bending moment becomes sufficiently large, i.e. when the stress induced in the glass by bending exceeds the breaking stress of the glass, the ribbon breaks at the scribe line, i.e. the glass sheet is released from the ribbon. Further description of the bending process can be obtained in commonly assigned US Pat. No. 6,616,025 to Edward Andrewlavage, Jr., the entire contents of which are hereby incorporated by reference.

  Initially, ribbon non-flatness in nosing, such as the presence of gap 560 in FIG. 6, was not thought to be related to the poor quality edges seen in laser scoring. However, through experiments and computer analysis, it has been found that it is indeed non-flatness that causes poor quality edges. Specifically, it has been found that if the sheet separation process begins when the ribbon is in a non-flat state, substantial shear stress can be developed along the laser-scribed scribe line. When this shear stress is released by separation of the glass sheet, a jagged edge is generated. In mechanical scoring, the scoring lines are relatively easily separated, which limits the amount of stress that can be generated before separation, including the amount of shear stress, i.e., non-flat ribbons. Acceptable edge quality is also obtained. On the other hand, laser scoring is relatively difficult to separate at the scoring line, so the amount of stress, including shear stress, can increase, i.e., reach a level sufficient to create a jagged edge.

  According to experiments and computer analysis, the stress at the crease line is the distance between the crease line and the ribbon / sheet holding device (in this embodiment, the suction cup) of the sheet engagement assembly closest to this line. It was further shown to be related to L (see FIG. 10). In particular, it has been experimentally observed that separation essentially always begins in the area of the scoring line above or adjacent to the location of the holding device (eg, suction cup). Computer analysis showed that the magnitude of the principal stress at this position of the scribe line depends on the distance L. This effect is shown in FIG. In this figure, the vertical axis indicates the first principal stress in the crease line calculated by an arbitrary unit, and the horizontal axis indicates the distance from the ribbon center, also in the arbitrary unit. . The inner and outer edges of the holding device (suction cup) are indicated by vertical lines 810 and 820. Curve 800 shows the calculated reference stress distribution for L values suitable for mechanical scoring, while curves 801 and 802 show the results of decreasing and increasing L by approximately 25%, respectively. It is a thing. As can be seen, as L increases, the stress at the scribe line decreases (curve 802), whereas when L decreases, the stress increases (curve 801).

  From this analysis, it can be seen that by moving the closest ribbon / sheet holding device further away from the scoring line, the magnitude of the stress generated in the scoring line can be reduced. This means that the sheet engaging assembly can be further rotated around the scribe line before separation of the glass sheet begins. This rotation causes the ribbon to flatten against nosing, and correspondingly flatter, especially as rotation increases, so as the stress generated by increasing L decreases, the sheet engagement assembly Can be so great that the ribbon can be substantially completely flat against nosing before separation begins.

  The effect of this flattening associated with rotation of the seat engagement assembly is illustrated in FIG. Here, as compared with FIG. 6, as a result of the rotation, the gap 560 was significantly reduced. Further rotation will bring the glass in contact with the nosing, i.e., the glass can be in the desired substantially perfectly flat shape. In this way, i.e. by increasing L, the ribbon is already flat against nosing, i.e. not subject to too much shear stress, when the stress produced by rotation eventually exceeds the fracture stress of the glass. . If the shear stress is not that large, the edges of the glass sheet will not be jagged and the desired result will be obtained.

  This approach to improving the edge quality of glass sheets produced from laser-marked glass ribbons is due to the fact that nosing is flat in the direction across the ribbon. However, it has already been found that edge quality can be further improved if the nosing cross-section is a curve that makes contact between the second side of the ribbon and the nosing along a substantially single line. ing. Such curved nosing is shown in FIG. In this figure, reference numeral 570 indicates the direction of rotation of the seat engagement assembly 530. The curved nosing may be fixed or rotatable about an axis parallel to the scoring line. A variety of materials can be used for nosing, a suitable material being silicone rubber. Similarly, curved nosing can have various curvatures. For example, it has been found that 50 mm diameter is suitable for nosing with a circular cross section. While nosing with a curved cross-section improves edge quality, the planarization aspect of the present disclosure can be implemented with nosing with other cross-sectional shapes, such as a rectangular shape, if desired.

  In practice, to determine the distance L between the scoring line and the closest ribbon / sheet holding device that provides acceptable edge quality, observe the gap 560 and close the gap before separation begins. In addition, L is increased until separation is sufficiently delayed so that the surface 502 of the glass ribbon is in contact with the nosing. Alternatively, using the edge quality itself as a parameter to determine when L is sufficiently large, increase L until the occurrence of jagged edges is reduced to a desired level, eg, essentially no jagged edges are eliminated. You may let them. In any case, the adjustment of L is made straight forward, especially when the seat engagement assembly is operated by an industrial robot and the change of L can be realized by changing one or more operating parameters of the robot.

  The longer L means that the sheet engagement assembly 530 must be rotated further with respect to the scribe line before separation occurs, so the amount of L that can be increased by the speed of movement of the ribbon 33. Note that an upper limit is set. At a given rotational speed (eg, a rotational speed that matches the elastic properties of the glass), the time to rotate the sheet engagement assembly 530 is even longer, ie at some point the separation process lags behind the ribbon production speed. Will take. In practice, however, it has already been found that L can be increased to a level that substantially catches the jagged edge problem while easily catching up with the ribbon movement speed.

  11 to 16 show an embodiment of an apparatus for carrying out the above method for improving the edge quality of a glass sheet separated by a scribing line laser-marked from a glass ribbon. The apparatus further illustrates a further aspect of the present disclosure in which nosing is integrated with the sheet handling equipment, the sheet handling equipment (1) applying a bending moment to separate the glass sheet from the glass ribbon. (2) The separated glass sheet is moved away from the glass ribbon, and (3) the separated sheet is moved to a transfer facility engaged with the upper part of the sheet. Such an integrated nosing / seat handling assembly reduces costs and further simplifies the deployment of equipment under the stretch.

  In addition to its use as a pivot (fulcrum) for the ribbon bending process, the nosing of the one-piece assembly can be used as a backing for forming a scratch start point (see reference numeral 23 in FIG. 4) or as a machine rather than laser scoring. It can also be used as a backing for the entire scoring process when a manual scoring is performed. If nosing of the assembly is used only to create the scratch start and not as a fulcrum for sheet separation or as a backing for mechanical scoring across the full width of the ribbon, nosing of the assembly is It does not need to extend across the entire width, only a length that can generate a scratch start.

  The integrated assembly of FIGS. 11-16 can be operated with an industrial robot, where the assembly may be attached to the robot, for example, at the nominal center 670 of the device. The assembly may include a vacuum port 620 above and below the nosing as shown in FIG. 15 to recover the glass fragments produced when the glass sheet separates from the glass ribbon. This vacuum port may be connected to a vacuum system (not shown) through a vacuum plenum 630. The one-piece assembly is described in the above-referenced US Pat. No. 6,616,025, where once separated, the separated sheet can be automatically dropped from the moving ribbon. A connector assembly 650 may also be included.

  As noted above, in one embodiment, the assembly employs both a suction cup that engages the second surface 502 of the glass ribbon and a clamp pad that engages the first surface 501 and a sheet clamp unit 660. May be used. The clamp pad is moved relative to the ribbon using a pneumatic cylinder 680. In practice, the suction cup may be in close proximity to the second side of the ribbon and then a clamp pad may be used to press the sheet against the suction cup. This combination of suction cup and clamp pad increases the holding capacity, widens the process window, for example, making this equipment usable for ribbons that have a large distorted bow at the bottom of the stretch, and the consumption of the suction cup Can be reduced. As with the nosing, the pad and suction cup can be made of a variety of materials including, for example, silicone rubber.

  The integrated nosing / sheet handling assembly further includes an air cylinder 640 that is the plane defined by the sheet clamp unit, i.e., the second of the glass ribbon when the sheet clamp unit engages the glass ribbon. For moving the nosing into and out of this plane relative to the nominal plane of the face. In particular, nosing needs to be in this plane when supporting the ribbon during mechanical scoring and sheet separation, but exposes the upper edge of the sheet when moving the sheet to subsequent handling equipment. Therefore, it is necessary to be out of this plane. When the air cylinder is in the extended configuration (see FIGS. 11-14), the nosing is moved into the plane, while when in the contracted configuration (see FIG. 15), the nosing is moved out of the plane to expose the upper edge 690. . Of course, linkages other than those shown in FIGS. 11-15 may be used to move the nosing between the two positions, for example, a servo motor may be used for this purpose. it can.

  A typical movement of the integrated nosing / sheet handling assembly as the sheet is separated from the moving ribbon is shown in FIGS. FIG. 11 shows the assembly prior to engagement with the ribbon, and FIG. 12 shows the assembly immediately after engagement. Once engaged with the ribbon, the robot moves the assembly down at the same pace as the ribbon when creating a scratch start and laser scoring. The robot then rotates the assembly around the scoring line (or equivalently, around the leading edge of the nosing) to first flatten the ribbon against nosing and then separate the sheet from the ribbon. Let FIG. 13 shows the arrangement of the system immediately after the glass sheet is separated from the ribbon. Thereafter, as shown in FIG. 14, the assembly and the separated glass sheet are moved so that the robot moves away from the glass ribbon. Finally, in FIG. 15, the pneumatic cylinder 640 moves the nose away from the upper edge of the seat so that subsequent handling equipment can engage the seat from above. The robot then returns the assembly to the position in FIG. 11 and the process is repeated for the next glass sheet.

  Various modifications that do not depart from the scope and spirit of the invention will be apparent to those skilled in the art from the foregoing disclosure. The following claims are intended to cover the specific embodiments specified herein, as well as modifications, variations, and equivalents thereof.

13 Glass sheet 33 Ribbon 501 First side 502 Second side 510 Suction cup 520 Frame 530 Sheet engaging assembly 540 Nosing 620 Vacuum port 630 Vacuum plenum 660 Sheet clamp unit

Claims (6)

In a method for producing a glass sheet,
(I) forming a glass ribbon having a first surface and a second surface; and
(II) forming a plurality of glass sheets from the ribbon, the process of generating each glass sheet,
(A) forming a scribing line on the first surface of the glass ribbon using a laser; and
(B) separating the glass sheet from the glass ribbon at the scoring line, the separating process applying a bending moment at the scoring line to the laser scoring glass. Rotating the sheet engaging assembly about an axis through the writing line, wherein the sheet engaging assembly engages the frame and at least the second surface of the glass ribbon; A plurality of ribbon / sheet holding devices supported by the frame, wherein a distance between the crease line and the ribbon / sheet holding device closest to the crease line is L And
here,
(I) during step (II) (B), a nosing that is flat in a direction transverse to the ribbon engages the second surface of the ribbon at the scoring line;
(Ii) before the second rotation of step (II) (B) causes any separation of the glass sheet from the glass ribbon, so that the second surface of the ribbon spans substantially the entire width of the ribbon. A method characterized in that L is chosen to be sufficiently long so as to be in contact with nosing. In a method for improving the edge quality of a glass sheet, the process of producing the glass sheet comprises:
(I) forming a glass ribbon having a first surface and a second surface; and
(II) forming a plurality of glass sheets from the ribbon, the process of generating each glass sheet,
(A) forming a scribing line on the first surface of the glass ribbon using a laser; and
(B) separating the glass sheet from the glass ribbon at the scoring line, the separation process comprising:
Rotating a sheet engagement assembly about an axis passing through the scribe line while contacting a nosing that is flat in a direction across the ribbon to the second surface of the glass ribbon;
Wherein the sheet engagement assembly engages the frame and at least the second surface of the glass ribbon during the rotation and is supported by the frame / A sheet holding device, and a distance between the scoring line and the ribbon / sheet holding device closest to the scoring line is L,
The method includes the step of increasing L from a reference value suitable for mechanical scoring so as to improve the edge quality of the glass sheet separated from the ribbon.   3. The method of claim 2, wherein the frame is manipulated by a robot and L is increased by changing one or more operational parameters of the robot. In a method for producing a glass sheet,
(I) forming a glass ribbon having a first surface and a second surface; and
(II) forming a plurality of glass sheets from the ribbon, the process of generating each glass sheet,
(A) forming a scribing line on the first surface of the glass ribbon using a laser; and
(B) separating the glass sheet from the glass ribbon at the scoring line, the separating process applying a bending moment at the scoring line to the laser scoring glass. Rotating the sheet engaging assembly about an axis through the writing line, wherein the sheet engaging assembly engages the frame and at least the second surface of the glass ribbon; A plurality of ribbon / sheet holding devices supported by the frame;
here,
(I) During step (II), nosing supported by the frame engages the second surface of the ribbon at the scribing line;
(Ii) After step (II), the method includes moving the nosing away from the separated glass sheet to expose the upper edge of the sheet.   The method according to claim 1, wherein the nosing has a curved cross section.   6. A method according to any one of claims 1 to 5, characterized in that the nosing is rotatable about an axis parallel to the scribing line.

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