阅读说明：本技术 具有拉力测量的片材分离设备和方法 (Sheet separation apparatus and method with tension measurement ) 是由 R·R·奎尔 于 2018-06-26 设计创作，主要内容包括：用于从玻璃带分离玻璃片的设备和方法,包括：在玻璃带上施加拉力的夹持工具,所述拉力足以从玻璃带分离出玻璃片。所述夹持工具包括至少一个力测量装置,当夹持工具在玻璃带上施加拉力时,所述至少一个力测量装置进行多次的力测量。(An apparatus and method for separating a glass sheet from a glass ribbon comprising: a gripping tool that applies a pulling force on the glass ribbon sufficient to separate a glass sheet from the glass ribbon. The clamping tool includes at least one force measuring device that performs a plurality of force measurements as the clamping tool applies a pulling force on the glass ribbon.)

1. An apparatus for separating a glass sheet from a glass ribbon comprising:

a clamping tool configured to apply a pulling force on the glass ribbon sufficient to separate a glass sheet from the glass ribbon, wherein the clamping tool comprises at least one force measurement device configured to perform a plurality of force measurements as the clamping tool applies the pulling force on the glass ribbon.

2. The apparatus of claim 1, wherein the gripping tool comprises a plurality of gripping elements.

3. The apparatus of claim 1 or 2, wherein each gripping element comprises a vacuum cup.

4. A device as claimed in claim 2 or 3, wherein the clamping means comprises four corner regions and each corner region comprises a clamping element.

5. The apparatus of any one of claims 2 to 4, wherein two or more clamping elements are associated with corresponding force measuring devices.

6. The apparatus of any one of claims 1 to 5, wherein the at least one force measuring device comprises a load cell.

7. The apparatus of any one of claims 1 to 6, wherein the gripping means comprises a sheet tensioning mechanism.

8. The apparatus of any one of claims 1 to 7, wherein the apparatus further comprises a scoring mechanism.

9. A clamping tool configured to apply a pulling force on a glass ribbon, wherein,

the clamping tool includes at least one force measurement device configured to take a plurality of force measurements as the clamping tool applies a pulling force on the glass ribbon.

10. The gripping tool of claim 9, wherein the gripping tool comprises a plurality of gripping elements.

11. The gripping tool of claim 9 or 10, wherein each gripping element comprises a vacuum cup.

12. A gripping tool according to claim 10 or 11, wherein the gripping tool comprises four corner regions and each corner region comprises a gripping element.

13. The gripping tool of any of claims 10 to 12, wherein two or more gripping elements are associated with corresponding force measuring devices.

14. The clamping tool of any one of claims 9 to 13, wherein the at least one force measuring device comprises a load cell.

15. A gripping tool according to any of claims 9 to 14, wherein the gripping tool comprises a sheet tensioning mechanism.

16. A method of separating a glass sheet from a glass ribbon, the method comprising applying a pulling force on the glass ribbon with a clamping tool, wherein the pulling force is sufficient to separate the glass sheet from the glass ribbon, and wherein the clamping tool comprises at least one force measuring device that performs a plurality of force measurements as the clamping tool applies the pulling force on the glass ribbon.

17. The method of claim 16, wherein the gripping tool comprises a plurality of gripping elements.

18. The method of claim 16 or 17, wherein each gripping element comprises a vacuum cup.

19. The method of claim 17 or 18, wherein the gripping tool comprises four corner regions and each corner region comprises a gripping element.

20. The method of any one of claims 17 to 19, wherein two or more clamping elements are associated with corresponding force measuring devices.

21. The method of claim 20, wherein the method further comprises: multiple force measurements are analyzed.

22. The method of any of claims 16 to 21, wherein the at least one force measurement device comprises a load cell.

23. The method of any of claims 16 to 22, wherein the method further comprises: the glass ribbon is tensioned using a sheet tensioning mechanism.

Technical Field

The present disclosure relates generally to apparatus and methods for separating a glass sheet from a glass ribbon, and more particularly, to apparatus and methods for measuring tension during a sheet separation process.

Background

In the production of glass articles, such as glass sheets for display applications including televisions and hand-held devices, such as telephones and tablets, glass sheets can be separated from a continuously formed glass ribbon. Methods of separating a glass sheet from a glass ribbon include scoring the glass ribbon along a desired separation line and drawing the glass ribbon to form an arch, thereby creating a bending stress in the glass that increases as the pulling force increases. When the bending stress, along with other stresses (e.g., thermal expansion), is of sufficient magnitude and orientation, a fracture will occur along the score line resulting in a separated glass sheet.

Since many variables can affect the bending of the glass ribbon and the separation of the glass sheet from the glass ribbon, these variables can in turn affect the quality of the separation, including the quality of the edges of the glass sheet along the separation line. For example, when one or more variables affecting bending and separation of the glass sheet are not clear, defects known to those of ordinary skill in the art, such as what are known as chips, serrations, or dog-ears, may occur. Accordingly, a more complete understanding of the stresses imposed on the glass during the separation process is desired, thereby enabling a better understanding and control of the variables that affect the bending and separation of the glass sheet, thereby minimizing the occurrence of separation-related defects.

Disclosure of Invention

Embodiments disclosed herein include an apparatus for separating a glass sheet from a glass ribbon. The apparatus includes a gripping tool configured to apply a pulling force on the glass ribbon sufficient to separate a glass sheet from the glass ribbon. The clamping tool includes at least one force measuring device configured to take a plurality of force measurements as the clamping tool applies a force on the glass ribbon.

Embodiments disclosed herein also include a clamping tool configured to apply a pulling force on the glass ribbon. The clamping tool includes at least one force measuring device configured to take a plurality of force measurements as the clamping tool applies a force on the glass ribbon.

Embodiments disclosed herein also include methods of separating a glass sheet from a glass ribbon. The method comprises the following steps: a pulling force is applied to the glass ribbon with the gripping tool. The pulling force is sufficient to separate the glass sheet from the glass ribbon, and the gripping tool includes at least one force measuring device that takes a plurality of force measurements as the gripping tool exerts the pulling force on the glass ribbon.

Additional features and advantages of the embodiments disclosed herein are set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the embodiments disclosed herein, including the detailed description which follows, the claims, as well as the appended drawings.

It is to be understood that both the foregoing general description and the following detailed description present embodiments of the disclosure, and are intended to provide an overview or framework for understanding the nature and character of the claimed embodiments. The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate various embodiments of the disclosure and, together with the description, serve to explain the principles and operations of the disclosure.

Drawings

FIG. 1 is a schematic view of an exemplary fusion downdraw glass manufacturing apparatus and method;

FIG. 2 is a schematic side view of a stage of an exemplary glass sheet separation process;

FIG. 3 is a schematic side view of another stage of an exemplary glass sheet separation process;

FIG. 4 is a schematic side view of another stage of an exemplary glass sheet separation process;

FIG. 5 is a schematic side view of another stage of an exemplary glass sheet separation process;

FIG. 6 is a schematic front view of an exemplary glass sheet clamping tool;

FIG. 7 is a bottom cross-sectional schematic view of a portion of an exemplary glass sheet clamping tool with a sheet tensioning mechanism in a first position;

FIG. 8 is a bottom cross-sectional schematic view of the exemplary glass sheet holding tool portion of FIG. 7 with the sheet tensioning mechanism in a second position;

FIG. 9 is a bottom cross-sectional schematic view of the exemplary glass sheet holding tool portion of FIG. 7 including the force measuring device in a first position;

FIG. 10 is a bottom cross-sectional schematic view of the exemplary glass sheet holding tool portion of FIG. 7 including the force measuring device in a second position;

FIG. 11 is a bottom cross-sectional schematic view of the exemplary glass sheet holding tool portion of FIG. 7 including the force measuring device in a third position;

FIG. 12 is a schematic cross-sectional side view of the exemplary glass sheet holding tool portion of FIG. 7 including a force measuring device in a fourth position;

FIG. 13 is a graph showing the measured strain as a function of time as the clamping tool applies a pulling force on the glass ribbon.

Detailed Description

Reference will now be made in detail to the preferred embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. This disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

Ranges can be expressed herein as from "about" one particular value, and/or to "about" another particular value. When such a range is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent "about," it will be understood that the particular value forms another embodiment. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.

Directional terms used herein, such as upper, lower, right, left, front, rear, top, bottom, are used only with reference to the drawings, and are not intended to imply absolute orientations.

Unless specifically stated otherwise, any methods described herein should not be construed as requiring that their steps be performed in a particular order, or that any apparatus be specifically oriented. Accordingly, if a method claim does not actually recite an order to be followed by its steps, or any apparatus claim does not actually recite an order or orientation to individual components, or no further limitation to a specific order is explicitly stated in the claims or specification, or a specific order or orientation is recited to components of an apparatus, then no order or orientation should be inferred, in any respect. This applies to any possible non-expressive basis for interpretation, including: a logical problem related to the arrangement of steps, a flow of operations, an order of components, or an orientation of components; obvious meaning derived from grammatical organization or punctuation, and quantity or type of implementation described in the specification.

As used herein, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a" or "an" element includes aspects having two or more such elements, unless the context clearly indicates otherwise.

As used herein, the term "vacuum source" refers to a source capable of generating at least a partial vacuum in a device, system or component, and the device, system or component is in fluid communication with the vacuum source.

FIG. 1 illustrates an exemplary glass manufacturing apparatus 10. In some examples, the glass manufacturing apparatus 10 may include a glass melting furnace 12, and the glass melting furnace 12 may include a melting vessel 14. In addition to the melting vessel 14, the glass melting furnace 12 may optionally include one or more additional components, such as heating elements (e.g., burners or electrodes) that heat and convert the raw materials into molten glass. In further examples, the glass melting furnace 12 may include thermal management devices (e.g., insulation members) that reduce heat loss near the melting vessel. In further examples, the glass melting furnace 12 may include electronic and/or electromechanical devices that facilitate melting the raw materials into a glass melt. Still further, the glass melting furnace 12 may include support structures (e.g., support bases, support members, etc.) or other components.

The glass melting vessel 14 typically comprises a refractory material, for example a refractory ceramic material such as a refractory ceramic material comprising alumina or zirconia. In some examples, the glass melting vessel 14 may be constructed from refractory ceramic bricks. Specific embodiments of the glass melting vessel 14 will be described in more detail below.

In some examples, a glass melting furnace may be incorporated as a component of a glass manufacturing apparatus to manufacture glass substrates, such as glass ribbons having a continuous length. In some examples, a glass melting furnace of the present disclosure may be incorporated as a component of a glass manufacturing apparatus, including a slot draw apparatus, a float bath apparatus, a downdraw apparatus (e.g., a fusion process apparatus), an updraft apparatus, a press roll apparatus, a tube draw apparatus, or any other glass manufacturing apparatus that would benefit from aspects disclosed herein. For example, FIG. 1 schematically illustrates a glass melting furnace 12 as a component of a fusion downdraw glass manufacturing apparatus 10, the fusion downdraw glass manufacturing apparatus 10 being used to fusion draw a glass ribbon for subsequent processing of the glass ribbon into individual glass sheets.

The glass manufacturing apparatus 10 (e.g., fusion downdraw apparatus 10) can optionally include an upstream glass manufacturing apparatus 16, with the upstream glass manufacturing apparatus 16 being located upstream of the glass melting vessel 14. In some examples, a portion or the entirety of the upstream glass manufacturing apparatus 16 may be incorporated as part of the glass melting furnace 12.

As shown in the illustrated example, the upstream glass manufacturing apparatus 16 can include a storage bin 18, a raw material delivery device 20, and an engine 22 connected to the raw material delivery device. The storage bins 18 may be configured to store a quantity of raw material 24, and the raw material 24 may be fed into the melting vessel 14 of the glass melting furnace 12, as indicated by arrow 26. The feedstock 24 typically comprises one or more glass-forming metal oxides and one or more modifiers. In some examples, the feedstock delivery device 20 may be powered by the engine 22 such that the feedstock delivery device 20 delivers a predetermined amount of feedstock 24 from the storage bin 18 to the melting vessel 14. In further examples, engine 22 may power feedstock delivery device 20 to add feedstock 24 at a controlled rate based on a sensed level of molten glass downstream of melting vessel 14. Thereafter, the raw materials 24 within the melting vessel 14 may be heated to form molten glass 28.

The glass manufacturing apparatus 10 may also optionally include a downstream glass manufacturing apparatus 30 located downstream of the glass melting furnace 12. In some examples, a portion of the downstream glass manufacturing apparatus 30 may be incorporated as part of the glass melting furnace 12. In some cases, the first connecting conduit 32, as discussed below, or other portions of the downstream glass manufacturing apparatus 30, may be incorporated as part of the glass melting furnace 12. The elements of the downstream glass manufacturing apparatus, including the first connecting conduit 32, may be formed from a precious metal. Suitable noble metals include platinum group metals selected from the group consisting of: platinum, iridium, rhodium, osmium, ruthenium, and palladium, or alloys thereof. For example, downstream components of the glass manufacturing apparatus may be formed from a platinum-rhodium alloy comprising from about 70 wt.% to about 90 wt.% platinum and from about 10 wt.% to about 30 wt.% rhodium. However, other suitable metals may include molybdenum, palladium, rhenium, tantalum, titanium, tungsten, and alloys thereof.

Downstream glass manufacturing apparatus 30 may include a first conditioning (i.e., processing) vessel, such as fining vessel 34, located downstream from melting vessel 14 and connected to melting vessel 14 by first connecting conduit 32 as described above. In some examples, molten glass 28 may be fed by gravity from melting vessel 14 to fining vessel 34 via first connecting conduit 32. For example, gravity may cause molten glass 28 to pass from melting vessel 14 to fining vessel 34 through the internal passage of first connecting conduit 32. It should be understood that other conditioning vessels may be located downstream of the melting vessel 14, such as between the melting vessel 14 and the fining vessel 34. In some embodiments, a conditioning vessel may be used between the melting vessel and the fining vessel, wherein molten glass from the main melting vessel is further heated to continue the melting process, or cooled to a lower temperature than the temperature of the molten glass in the melting vessel prior to entering the fining vessel.

In fining vessel 34, bubbles can be removed from molten glass 28 by various techniques. For example, the feedstock 24 may include multivalent compounds (i.e., fining agents), such as tin oxides, that chemically reduce and release oxygen when heated. Other suitable fining agents include, but are not limited to, arsenic, antimony, iron, and cerium. Fining vessel 34 is heated to a higher temperature than the melting vessel, thereby heating the molten glass and fining agents. Oxygen bubbles generated by the temperature-induced chemical reduction reaction of the fining agent rise through the molten glass within the fining vessel, wherein gases within the molten glass generated within the melting furnace may diffuse or coalesce into the oxygen bubbles generated by the fining agent. The enlarged bubbles may then rise to the free surface of the molten glass in the fining vessel and then exit the fining vessel. The oxygen bubbles may further initiate mechanical mixing of the molten glass in the fining vessel.

The downstream glass manufacturing apparatus 30 may also include another conditioning vessel, such as a mixing vessel 36 for mixing molten glass. Mixing vessel 36 may be located downstream of fining vessel 34. Mixing vessel 36 may be used to provide a uniform glass melt composition, thereby reducing striae caused by chemical or thermal inhomogeneities that may otherwise be present in the refined molten glass exiting the fining vessel. As shown, the fining vessel 34 may be connected to the mixing vessel 36 by a second connecting conduit 38. In some examples, molten glass 28 may be fed from fining vessel 34 to mixing vessel 36 via second connecting conduit 38 by gravity. For example, gravity may cause molten glass 28 to pass from fining vessel 34 to mixing vessel 36 through the internal passage of second connecting conduit 38. It should be noted that although mixing vessel 36 is shown downstream of fining vessel 34, mixing vessel 36 may be located upstream of fining vessel 34. In some embodiments, downstream glass manufacturing apparatus 30 may include multiple mixing vessels, such as a mixing vessel located upstream of fining vessel 34 and a mixing vessel located downstream of fining vessel 34. These multiple mixing vessels may be of the same design, or they may be of different designs.

The downstream glass manufacturing apparatus 30 can also include another conditioning vessel, such as a delivery vessel 40, which can be located downstream of the mixing vessel 36. Delivery vessel 40 can condition molten glass 28 to be fed into a downstream forming device. For example, delivery vessel 40 can function as an accumulator and/or a flow controller to regulate the flow of molten glass 28 and/or to provide a constant flow of molten glass 28 to forming body 42 through outlet conduit 44. As shown, the mixing vessel 36 may be connected to the delivery vessel 40 by a third connecting conduit 46. In some examples, molten glass 28 may be fed from mixing vessel 36 to delivery vessel 40 by gravity through third connecting conduit 46. For example, gravity may drive molten glass 28 from mixing vessel 36 to delivery vessel 40 through the internal passage of third connecting conduit 46.

The downstream glass manufacturing apparatus 30 can also include a forming apparatus 48, with the forming apparatus 48 including the forming body 42 and the inlet conduit 50 described above. Outlet conduit 44 can be positioned to deliver molten glass 28 from delivery vessel 40 to inlet conduit 50 of forming apparatus 48. For example, in some examples, outlet conduit 44 may be nested in an inner surface of inlet conduit 50 and spaced apart from the inner surface of inlet conduit 50, thereby providing a free surface of molten glass between the outer surface of outlet conduit 44 and the inner surface of inlet conduit 50. The forming body 42 in a fusion downdraw glass manufacturing apparatus can include a trough 52 in an upper surface of the forming body and converging forming surfaces 54 that converge in the draw direction along a bottom edge 56 of the forming body. The molten glass delivered to the forming body trough via delivery vessel 40, outlet conduit 44 and inlet conduit 50 overflows the side walls of the trough and descends along converging forming surfaces 54 as separate streams of molten glass. The separate flows of molten glass join below and along the bottom edge 56 to create a single glass ribbon 58, the single glass ribbon 58 being drawn from the bottom edge 56 in the draw or flow direction 60 by applying tension to the glass ribbon (e.g., by gravity, edge rollers 72, and pulling rollers 82) to control the size of the glass ribbon as the glass cools and the viscosity of the glass increases. Thus, the glass ribbon 58 undergoes a viscoelastic transition and acquires mechanical properties that provide the glass ribbon 58 with stable dimensional characteristics. In some embodiments, glass ribbon 58 can be separated into individual glass sheets 62 in the elastic zone of the glass ribbon using glass separation apparatus 100. Robot 64 may then use gripping tool 65 to transfer each glass sheet 62 to a conveyor system, from which each glass sheet may be further processed.

Fig. 2 shows a schematic side view of a stage of an exemplary glass sheet separation process. As shown in FIG. 2, the glass separation apparatus 100 includes a scoring mechanism 102 and a nosing 104, wherein the scoring mechanism 102 and nosing 104 are located on opposite sides of the glass ribbon 58. In the stage shown in fig. 2, the scoring mechanism 102 moves widthwise across the glass ribbon 58 and imparts a widthwise score line on the glass ribbon 58. Further, in the stage shown in FIG. 2, the clamping tool 65 has not yet engaged the glass ribbon 58, although engagement while scoring is also known in the art and is typically performed as such.

Although the scoring mechanism 102 is shown in fig. 2 as a mechanical scoring mechanism, such as a mechanism comprising a scoring wheel, it should be understood that embodiments herein include other types of scoring mechanisms, such as a laser scoring mechanism. When the scoring mechanism 102 comprises a scoring wheel, the scoring wheel can be mounted on a ball bearing pivot secured to a shaft, which in turn is mounted on a linear actuator (air cylinder) that moves the scoring wheel toward the glass ribbon 58 so that it can be pulled and scored on one side of the glass ribbon.

The flange 104 may comprise a resilient material, such as silicone rubber. In certain exemplary embodiments, the flange 104 may be a compliant flange having the arcuate shape of the glass ribbon 58, as disclosed in, for example, U.S. patent No. 8,051,681, the entire disclosure of which is incorporated herein by reference. The flange 104 may also be in fluid communication with a vacuum source (not shown) to enhance the engagement between the glass ribbon 58 and the flange, as disclosed in, for example, U.S. patent No. 8,245,539, the entire disclosure of which is incorporated herein by reference.

FIG. 3 shows a side schematic view of another stage of an exemplary glass sheet separation process in which the scoring mechanism 102 is disengaged from the glass ribbon 58 and the clamping tool 65 (including the clamping element 66) is actuated by the robot 64 to engage the glass ribbon 58. The clamping element 66 may comprise, for example, an elastomeric material, such as silicone rubber, and in certain exemplary embodiments, may comprise a cup-shaped elastomeric material that may be in fluid communication with a vacuum source (not shown) to enhance engagement between the glass ribbon 58 and the clamping element 66 (the clamping element comprising the cup-shaped material and in fluid communication with the vacuum source is hereinafter referred to as a vacuum cup).

As shown in fig. 3, while the clamping tool 64 (including the clamping element 66) exerts a pulling force on the glass ribbon 58, the pulling force is not sufficient to significantly bend the glass ribbon 58 away from the draw or flow direction 60. However, fig. 4 shows a schematic side view of another stage of the exemplary glass sheet separation process in which the gripping tool 65 is further actuated by the robot 64, thereby applying a pulling force and sufficient to initiate bending of the portion of the glass ribbon 58 extending below the flange 104 away from the draw or flow direction 60. However, as shown in fig. 4, the pulling force is still insufficient to substantially separate the portion of the glass ribbon 58 extending below the flange 104 from the remainder of the glass ribbon 58.

Fig. 5 shows a schematic side view of another stage of the exemplary glass sheet separation process, wherein the gripping tool 65 is further actuated by the robot 65, thereby applying a pulling force and the pulling force is sufficient to separate the portion of the glass ribbon 58 (i.e., the glass sheet) extending below the flange 104 from the remainder of the glass ribbon 58. The glass sheet may then be transferred, for example, to a conveyor system for further processing.

Fig. 6 shows a schematic front view of an exemplary glass sheet holding tool 65. The clamping tool 65 comprises four corner regions A, B, C and D, respectively, and each corner region contains a clamping element 66. As shown in fig. 6, the clamping means 65 further comprises clamping elements 66 between the clamping elements in the corner regions a and C, and clamping elements 66 between the clamping elements in the corner regions B and D, thus totaling six clamping elements. However, it should be understood that the clamping means encompassed by embodiments disclosed herein comprise any number of clamping elements in any pattern or arrangement. For example, in certain embodiments, the gripping tool 65 may include gripping elements only at corner regions A, B, C, D, thus totaling four gripping elements. The gripping tool 65 may also include more than one gripping element between the gripping elements in corner regions a and C, and more than one gripping element between the gripping elements in corner regions B and D (i.e., multiple columns of gripping elements between corner regions a and C and another multiple columns of gripping elements between corner regions B and D). For example, the gripping tool 65 may include a gripping element located in the center of the gripping tool 65.

Fig. 7 shows a bottom cross-sectional schematic view of a portion of an exemplary glass sheet clamping tool 65 with the sheet tensioning mechanism in a first position. The sheet tensioning mechanism includes a sheet tensioning cylinder 74 and a movable slide plate 73 on which is mounted a clamping member mounting block 68, the clamping member mounting block 68 being in fluid communication with a vacuum fitting 69 and a clamping member connector 67 (e.g., a draw nut) mounted on the clamping member mounting block 68. A gripping element 66 (e.g., a vacuum cup) is mounted on the gripping element connector 67 and is in fluid communication with the gripping element connector 67, and a vacuum fitting 69 is in fluid communication with a vacuum source (not shown), thereby allowing fluid communication between the gripping element 66 and the vacuum source through the vacuum fitting 69, the gripping element mounting block 68, and the gripping element connector 67. The gripping tool 65 further comprises an arm 71, an arm mounting block 70 and an end face 72.

FIG. 8 illustrates a bottom cross-sectional schematic view of the exemplary glass sheet holding tool portion of FIG. 7 with the sheet tensioning mechanism in a second position. As shown in fig. 8, the sheet tensioning cylinder 74 actuates the lateral movement of the slide plate 73 in the direction indicated by the arrow M and moves the gripping member mounting block 68, the vacuum fitting 69, the gripping member connector 67, and the gripping member 66 correspondingly. The sheet tensioning mechanism on the opposite side of the gripping tool 65 may be correspondingly moved, for example, in a direction opposite to that indicated by arrow M. The lateral movement of the sheet tensioning mechanism can increase the planarization of the glass sheet engaged by the clamping element 66. Such lateral movement may occur, for example, after the glass sheet has been separated from the glass ribbon 58, or between when the clamping tool 65 initially engages the glass ribbon 58 (as shown in fig. 3) and when the clamping tool 65 applies a pulling force sufficient to initiate bending of the portion of the glass ribbon 58 extending below the flange 104 away from the draw or flow direction 60 (as shown in fig. 4).

As the clamping tool 65 exerts a pulling force on the glass ribbon 58 (e.g., as shown in fig. 3-5), it induces a bending stress on the glass ribbon 58, and measuring the pulling force or forces on the glass ribbon 58 provides quantitative information about the bending stress experienced by the glass ribbon 58 during the sheet separation process. Tension measurements may be made according to embodiments disclosed herein, wherein the clamping tool 65 includes at least one force measuring device configured to take multiple tension measurements as the clamping tool 65 applies tension on the glass ribbon 58.

FIG. 9 shows a bottom cross-sectional schematic view of the exemplary glass sheet holding tool portion of FIG. 7 including the force measuring device 75a in a first position. As shown in fig. 9, the force measuring device 75a is located between the clamping member 66 and the clamping member mounting block 68. The force measuring device 75a may be, for example, an annular load cell circumferentially surrounding the clamping element connector 67, such as a miniature low-profile perforated press-type load cell available from Omega Engineering.

Fig. 10 shows a bottom cross-sectional schematic view of the exemplary glass sheet holding tool portion of fig. 7 including the force measuring device 75b in a second position. As shown in fig. 10, the force measuring device 75b is located between the slide plate 73 and the clamping member mounting block 68. The force measuring device 75b may be, for example, a miniature low-profile universal load cell operating in either a tension or compression mode, such as the MLP series low-profile universal load cell available from Transducer technologies.

Fig. 11 shows a bottom cross-sectional schematic view of the exemplary glass sheet holding tool portion of fig. 7 including the force measuring device 75b in a third position. As shown in fig. 11, the force measuring device 75b is located at the location of the arm mounting block 70, and in this regard, it may be located on the arm mounting block 70 or in place of the arm mounting block 70. Like the force measurement device 75b illustrated in FIG. 10, the force measurement device 75b may be, for example, a miniature low-profile universal load cell operating in either a tension or compression mode, such as the MLP series low-profile universal load cell available from transducer technologies.

FIG. 12 shows a schematic side cross-sectional view of the exemplary glass sheet holding tool portion of FIG. 7 including the force measuring device 75c in a fourth position. As shown in fig. 12, a force measuring device 75c is located on or in the arm 71. The force measuring device 75c may be, for example, a thin beam sensor calibrated to correlate deflection of the arm 71 with a pulling or pushing force on the clamping element 66, such as a TBS series full bridge thin beam sensor available from Transducer technologies or a full bridge thin beam load cell available from Omega Engineering. Although fig. 12 shows the force measuring device 75c at a particular location, the force measuring device 75c may be mounted at any location where the deflection of the arm 71 is associated with a strong pulling or pushing force on the clamping element 66. This correlation may be enhanced by increasing the degree of strain in the arm 71 at or near the location of the force measuring device, such as by forming a cut-out 76 on the side of the arm 71 opposite the force measuring device 75 c.

When positioning the force measuring devices (75a, 75b, 75c), care is taken to adequately protect the devices from heat sources, particularly heat radiating from the glass ribbon 58, as the force measuring devices may be sensitive to temperature. It may also be beneficial to use a force measuring device that is relatively less sensitive to temperature. In addition, care is taken to adequately protect the device from glass fragments and other materials.

Embodiments disclosed herein include embodiments in which each gripping element 66 of the gripping tool 65 is associated with a corresponding force measuring device, such as force measuring devices 75a, 75b, and 75c shown in fig. 9-12. For example, embodiments disclosed herein include embodiments in which the clamping tool 65 includes four corner regions (e.g., as shown in fig. 6) and each corner region includes a clamping element 66 and a corresponding force measurement device. Embodiments disclosed herein also include embodiments in which the gripping tool 65 comprises any number of multiple gripping elements and each gripping element 66 is associated with a corresponding force measuring device.

Embodiments disclosed herein include embodiments without a sheet tensioning mechanism and with the clamp element mounting block 68 attached directly to the arm mounting block 70 or the clamp element mounting block 68 attached directly to the arm 71, for example.

The at least one force measurement device, such as force measurement devices 75a, 75b, and 75c illustrated in fig. 9-12, may perform a plurality of force measurements while the clamping tool 65 is exerting a pulling force on the glass ribbon 58, such as at least 2, further such as at least 5, further such as at least 10, further such as at least 100, further such as at least 1000, tension measurements while the clamping tool 65 is exerting a pulling force on the glass ribbon 58. Accordingly, embodiments disclosed herein include embodiments in which the clamping tool 65 includes any number of the plurality of clamping elements 66 and two or more clamping elements 66 are associated with corresponding force measurement devices, wherein each force measurement device makes multiple force measurements as the clamping tool 65 exerts a pulling force on the glass ribbon 58.

Fig. 13 is a graph showing the measured strain as a function of time when a gripping tool similar to gripping tool 65 illustrated in fig. 6 exerts a pulling force on a glass ribbon. To generate the data shown in fig. 13, the gripping tool was equipped with a thin beam sensor located on opposite arms of the gripping tool and calibrated to correlate the measured deflection of the arms with a known pull force. As can be seen from fig. 13, the point in time when the clamping tool applies a force on the glass ribbon to bend the glass ribbon, the point in time when the glass sheet is separated from the glass ribbon, and the point in time when the robot moves the glass sheet away from the glass ribbon can be clearly distinguished.

The embodiments disclosed herein provide a better understanding of not only the stresses experienced by the glass ribbon during the bending and separation process, but also factors that affect the quality of the separation of the glass sheet from the glass ribbon, such as factors that may affect defects associated with the separation (e.g., chips, serrations, or dog-ears). These factors include, for example, the position and orientation of the gripping tool when it initially engages the glass ribbon, the position of the flange, the position of the pulling roll, and the maximum extent to which the gripping tool will bend the glass ribbon and the rate at which the bending occurs. Accordingly, embodiments disclosed herein include analyzing multiple force measurements, including the force when the clamping tool initially engages the glass ribbon and the force when scoring the glass ribbon, wherein these analyses can increase the understanding and control of factors that affect the quality of separation of the glass sheet from the glass ribbon.

Although the above embodiments have been described with reference to a fusion down-draw process, it should be understood that the embodiments may also be applicable to other glass forming processes, such as float processes, slot draw processes, up-draw processes, tube draw processes, and roller processes.

It will be apparent to those skilled in the art that various modifications and variations can be made in the embodiments of the present disclosure without departing from the spirit and scope of the disclosure. Thus, it is intended that the present disclosure cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.