WO2019168951A1

WO2019168951A1 - Non-contact glass substrate guiding apparatus and method

Info

Publication number: WO2019168951A1
Application number: PCT/US2019/019791
Authority: WO
Inventors: I-Wen CHOU; Yao-Chang Huang; Po-Hao Kao; Jia-xing YE
Original assignee: Corning Incorporated
Priority date: 2018-02-28
Filing date: 2019-02-27
Publication date: 2019-09-06
Also published as: TW201936470A

Abstract

A method of transporting a glass substrate includes conveying the glass substrate horizontally along a glass conveyance path in a vertical orientation, blowing a first fluid stream against only a portion of a first side of the glass substrate with a first blower, and blowing a second fluid stream against only a portion of a second side of the glass substrate with a second blower positioned opposite the first blower. The glass substrate includes a fixed end defining a top of the glass substrate and a free end defining a bottom of the glass substrate. The first blower and the second blower provide a guiding torque to the free end of the glass substrate and suppress movement of the free end of the glass substrate in a direction transverse to the glass conveyance path.

Description

NON-CONTACT GLASS SUBSTRATE GUIDING APPARATUS AND METHOD

BACKGROUND

[0001] This application claims the benefit of priority under 35 U.S.C. § 119 of U.S.

Provisional Application Serial No. 62/636, 310 filed on February 28, 2018, the content of which is relied upon and incorporated herein by reference in its entirety.

Field

[0002] The present specification generally relates to apparatuses and methods for transporting glass substrates and, more specifically, to non-contact glass substrate guiding apparatuses and method for transporting glass substrates.

Technical Background

[0003] When a glass ribbon (e.g., for a liquid crystal display (LCD glass sheet) is manufactured, substrates cut from the glass ribbon may need to be transported for additional processing. Such glass substrates may be transported through different manufacturing processes or around structures while being vertically suspended from conveyor. During such conveyance, a free end of the glass substrate may experience a flapping phenomenon, wherein the free end of the glass substrate may incidentally contact surrounding structures potentially resulting in damage to the glass substrate.

[0004] Accordingly, a need exists for alternative non-contact glass substrate guiding apparatuses and methods for suppressing and/or preventing the flapping phenomenon while a glass substrate is being transported.

SUMMARY

[0005] In one embodiment, a method of transporting a glass substrate includes conveying the glass substrate horizontally along a glass conveyance path in a vertical orientation, blowing a first fluid stream against only a portion of a first side of the glass substrate with a first blower, and blowing a second fluid stream against only a portion of a second side of the glass substrate with a second blower positioned opposite the first blower. The glass substrate includes a fixed end defining a top of the glass substrate and a free end defining a bottom of the glass substrate. The first blower and the second blower direct a guiding torque to the free end of the glass substrate and suppress movement of the free end of the glass substrate in a direction transverse to the glass conveyance path.

[0006] In another embodiment, a non-contact glass substrate guiding apparatus includes a first blower positioned along a glass conveyance path and a second blower positioned along the glass conveyance path opposite the first blower. The glass conveyance path is defined at an upper extent by a conveyor operable to horizontally convey a glass substrate in a vertical orientation such that one end of the glass substrate conveyed along the glass conveyance path is coupled to the conveyor and a free end of the glass substrate conveyed along the glass conveyance path is unrestrained to the conveyor at a lower extent of the glass conveyance path. The first blower is positioned along the glass conveyance path so as to direct a first fluid stream toward the lower extent of the glass conveyance path. The second blower is positioned along the glass conveyance path so as to direct a second fluid stream toward the lower extent of the glass conveyance path. The first and second fluid streams are configured to contact only a portion of a first side and a second side of the glass substrate, respectively, and direct a guiding torque to the free end of the glass substrate conveyed along the glass conveyance path to suppress movement of the free end of the glass substrate transverse to the glass conveyance path.

[0007] In yet another embodiment, a glass substrate conveyance assembly includes a conveyor defining an upper extent of a glass conveyance path and including a clamp and a non-contact glass substrate guiding apparatus. The conveyor is operable to convey a glass substrate horizontally along the glass conveyance path in a vertical orientation such that one end of the glass substrate conveyed along the glass conveyance path is coupled to the conveyor by the clamp and a free end of the glass substrate conveyed along the glass conveyance path is unrestrained to the conveyor at a lower extent of the glass conveyance path. The non-contact glass substrate guiding apparatus includes a first blower positioned along the glass conveyance path and a second blower positioned along the glass conveyance path opposite the first blower. The first blower is positioned along the glass conveyance path so as to direct a first fluid stream toward the lower extent of the glass conveyance path. The second blower is positioned along the glass conveyance path so as to direct a second fluid stream toward the lower extent of the glass conveyance path. The first and second fluid streams are configured to contact only a portion of a first side and a second side of the glass substrate, respectively, and direct a guiding torque to the free end of the glass substrate conveyed along the glass conveyance path to suppress movement of the free end of the glass substrate transverse to the glass conveyance path.

[0008] These and additional features provided by the embodiments described herein will be more fully understood in view of the following detailed description, in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The embodiments set forth in the drawings are illustrative and exemplary in nature and not intended to limit the subject matter defined by the claims. The following detailed description of the illustrative embodiments can be understood when read in conjunction with the following drawings, where like structure is indicated with like reference numerals and in which:

[0010] FIG. 1 depicts a diagrammatic illustration of a glass manufacturing system, according to one or more embodiments shown and described herein;

[0011] FIG. 2A depicts a side view of a glass substrate conveyance assembly, according to one or more embodiments shown and described herein;

[0012] FIG. 2B depicts a cross-sectional view of the glass substrate conveyance assembly of FIG. 2A, wherein a glass substrate experiences a flapping phenomenon without application of a non-contact glass substrate guiding apparatus;

[0013] FIG. 3 illustrates an fluid stream profile, according to one or more embodiments shown and described herein;

[0014] FIG. 4 depicts a flow diagram of a method of transporting a glass substrate, according to one or more embodiments shown and described herein;

[0015] FIG. 5A illustrates a non-contact glass substrate guiding apparatus providing a guiding torque to a free end of a glass substrate, according to one or more embodiments shown and described herein; [0016] FIG. 5B illustrates the non-contact glass substrate guiding apparatus of FIG.

5A providing a balanced flow force to the free end of the glass substrate, according to one or more embodiments shown and described herein;

[0017] FIG. 6A generally illustrates a non-contact glass substrate guiding apparatus as applied to an exemplary bottom-of-draw process, according to one or more embodiments shown and described herein;

[0018] FIG. 6B illustrates a cross-sectional top view of the manufacturing assembly of FIG. 6A, according to one or more embodiments shown and described herein;

[0019] FIG. 6C illustrates a cross-sectional front view of the manufacturing assembly of FIG. 6A, according to one or more embodiments shown and described herein;

[0020] FIG. 7A illustrates a top view of a non-contact glass substrate guiding apparatus as applied to another exemplary bottom-of-draw process, according to one or more embodiments shown and described herein; and

[0021] FIG. 7B illustrates a cross-sectional front view of the non-contact glass substrate guiding apparatus as applied to the glass lamination assembly of FIG. 7A, according to one or more embodiments shown and described herein.

DETAILED DESCRIPTION

[0022] Embodiments of the present disclosure are directed to non-contact glass substrate guiding apparatuses and methods of transporting a glass substrate. Such

apparatuses include at least a first blower positioned along a glass conveyance path and a second blower positioned along the glass conveyance path opposite the first blower. A glass substrate may be transported horizontally in a vertical orientation along the glass conveyance path through a variety of bottom-of-draw manufacturing processes and equipment. The first blower may be positioned along the glass conveyance path so as to direct a first fluid stream toward lower extent of the glass conveyance path and the second blower may be positioned along the glass conveyance path so as to direct a second fluid stream toward the lower extent of the glass conveyance path. The first and second fluid streams provided by the first and second blowers are configured to contact only a portion of a first side and a second side of the glass substrate, respectively, and direct a guiding torque to a glass substrate conveyed along the glass conveyance path to prevent movement of the glass substrate transverse to the glass conveyance path Accordingly, when a glass substrate is being transported along the glass conveyance path the guiding torque provided by the first and second blowers can guide the glass substrate so that it does make unwanted contact with bottom-of-draw equipment lining the glass conveyance path. Various embodiments of non-contact glass guiding apparatuses and methods of using the same will be described herein with specific reference to the appended drawings.

[0023] 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.

[0024] Directional terms as used herein - for example up, down, right, left, front, back, top, bottom - are made only with reference to the figures as drawn and are not intended to imply absolute orientation.

[0025] Unless otherwise expressly stated, it is in no way intended that any method set forth herein be construed as requiring that its steps be performed in a specific order, nor that with any apparatus specific orientations be required. Accordingly, where a method claim does not actually recite an order to be followed by its steps, or that any apparatus claim does not actually recite an order or orientation to individual components, or it is not otherwise specifically stated in the claims or description that the steps are to be limited to a specific order, or that a specific order or orientation to components of an apparatus is not recited, it is in no way intended that an order or orientation be inferred, in any respect. This holds for any possible non-express basis for interpretation, including: matters of logic with respect to arrangement of steps, operational flow, order of components, or orientation of components; plain meaning derived from grammatical organization or punctuation, and; the number or type of embodiments described in the specification. [0026] 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” component includes aspects having two or more such components, unless the context clearly indicates otherwise.

[0027] As used herein, the term“bottom-of-draw” (hereinafter“BOD”) refers to manufacturing processes occurring after molten glass has been formed into a glass ribbon, as will be described in greater detail herein. For example, BOD manufacturing processes may include glass cutting, vertical bead removal, measuring, weighing, cooling, laminating, coating, etc.

[0028] Referring now to FIG. 1, a schematic view of an example glass manufacturing system 100 is depicted. In this embodiment, the glass manufacturing system 100 uses the fusion process to make a continuous glass ribbon 154 from which glass substrates 155 are sectioned. The glass manufacturing system 100 includes a melting vessel 110, a fining vessel 115, a mixing vessel 120 (e.g., stir chamber 120), a delivery vessel 125 (e.g., bowl 125), a forming vessel 135 (e.g., isopipe 135), a pull roll assembly 140, a scoring device 150, a glass substrate conveyance assembly 151, and a BOD manufacturing process 200.

[0029] Glass batch materials are introduced into the melting vessel 110 as shown by arrow 112 and melted to form molten glass 126. The fining vessel 115 (e.g., finer tube 115) has a high temperature processing area that receives the molten glass 126 from the melting vessel 110 and in which bubbles are removed from the molten glass 126. The fining vessel 115 is connected to the mixing vessel 120 by a connecting tube 122. The mixing vessel 120 is connected to the delivery vessel 125 by connecting tube 127. The delivery vessel 125 delivers the molten glass 126 through a downcomer 130 to an inlet 132 and into the forming vessel 135 (e.g., an isopipe 135). The forming vessel 135 includes an opening 136 that receives the molten glass 126 which flows into a trough 137 and then overflows and runs down two sides l38a and l38b of the forming vessel 135 before fusing together at a root 139. The root 139 is where the two sides 138a and 138b come together and where the two overflow streams of molten glass 126 rejoin (e.g., refuse) before being drawn downward by the pull roll assembly 140 to form a glass ribbon 154. The scoring device 150 then cuts the glass ribbon 154 into distinct glass substrates 155 which are carried away by a glass substrate conveyance assembly 151 with a conveyor 152 and through one or more BOD manufacturing processes 200

[0030] The one or more BOD manufacturing processes 200 may include process which operates on a glass substrate 155 following separation of the glass substrate 155 from the glass ribbon 154. For example, the BOD manufacturing process 200 may include scoring, cutting, bead removal, measuring (e.g., by a thickness gauge), weighing, cooling, laminating, etc. In some embodiments, the conveyor 152 may transport the glass substrate 155 to and/or through multiple BOD manufacturing processes 200 or equipment lining the glass conveyance path 250. It is noted that while the present methods and non-contact glass substrate guiding apparatus, as will be discussed in greater detail herein, are discussed as being used in conjunction with BOD manufacturing process 200, it is contemplated that such methods and apparatuses may be applied equally to other downstream manufacturing processes. In the embodiments described herein, the non-contact glass substrate guiding apparatus may be integrated with the BOD manufacturing process 200 or separate and distinct from the BOD manufacturing process 200.

[0031] Although the glass manufacturing system 100 described herein uses the fusion process to make glass substrates 155, it should be understood that the non-contact glass substrate guiding apparatus and method 300 for transporting a glass substrate 155 described herein could be used with other types of glass manufacturing systems which form a glass ribbon from which discrete glass substrates are separated including, without limitation, slot- draw glass manufacturing systems and the like.

[0032] FIG. 2A illustrates a side view of a schematic representation of the glass substrate conveyance assembly 151 and FIG. 2B illustrates a cross-sectional front view of the glass substrate conveyance assembly 151. The glass substrate conveyance assembly 151 generally includes a conveyor 152, defining an upper extent of the glass conveyance path 250, and one or more conveyor clamps 153 configured to secure a glass substrate 155 to the conveyor 152. The conveyor 152 is an overhead conveyor that is operable to transport the glass substrate 155 horizontally along the glass conveyance path 250 with the glass substrate 155 vertically oriented (i.e., the major surfaces of the glass substrate 155 are generally parallel with the X-Z plane of the coordinate axes depicted in the figures). [0033] The glass substrate 155 includes a fixed end 160 defining a top of the glass substrate 155 and a free end 162 defining a bottom of the glass substrate 155. The glass substrate 155 further includes a leading edge 164 extending between the fixed end 160 and the free end 162. Though the glass substrate 155 is shown as having a rectangular shape, other polygonal and non-polygonal shapes are also contemplated. The glass substrate 155 may be used as display glass for various applications including, without limitation, smartphones, tablets, and other display devices. Accordingly, the glass substrate 155 may be very thin. For example, in embodiments, the glass substrate may have a thickness of 5 mm or less (e.g., 4 mm, 3 mm, 2 mm, 1.5 mm, 1 mm, 0.5 mm, or thinner). However, it is contemplated that glass substrates of greater thicknesses may also benefit from the methods and non-contact glass substrate guiding apparatuses as described herein.

[0034] The glass substrate 155 is suspended from the conveyor 152 at the fixed end

160 of the glass substrate 155. More particularly, the fixed end 160 of the glass substrate 155 may be coupled to the conveyor 152 with one or more conveyor clamps 153. In some embodiments, the one or more conveyor clamps 153 may include a first clamp l53a and a second clamp 153b. However, a greater or fewer number of conveyor clamps 153 may be used to secure the fixed end 160 of the glass substrate 155 to the conveyor 152. The free end 162 of the glass substrate 155 is unrestrained at a lower extent of the glass conveyance path 250 to the conveyor 152. By allowing the bottom of the glass substrate 155 to hang freely, contact with a majority of the major surfaces of the glass substrate 155 can be avoided during conveyance of the glass substrate 155.

[0035] The glass substrate conveyance assembly 151 transports the glass substrate

155 in a conveyance direction 252 along the glass conveyance path 250. As illustrated in FIG. 2A the conveyance direction 252 may be perpendicular to the leading edge 164 of the glass substrate 155. That is, in the embodiment depicted in FIG. 2A, the major surfaces of the glass substrate 155 are parallel to the X-Z plane of the coordinate axes depicted in the figure, as described herein, and the conveyance direction 252 is generally parallel to the +/- X direction of the coordinate axes depicted in the figure. Accordingly, it should be understood that the glass conveyance path 250 is parallel to the X-Z plane of the coordinate axes depicted in FIG. 2A and the glass substrate 155 is conveyed on the glass conveyance path 250 in the +X direction of the coordinate axes.

[0036] FIG. 2B illustrates a cross-sectional view of the glass substrate conveyance assembly 151 taken at the first pair of blowers 206 when viewed from a centerline of the glass conveyance path 250 in the +X direction of the illustrated coordinate axes. As illustrated in FIG. 2B, as the glass substrate 155 is transported along the glass conveyance path 250, the free end 162 of the glass substrate 155 may experience a flapping phenomenon wherein the free end 162 of the glass substrate 155 moves transverse to the glass conveyance path 250 (i.e., in the +/- Y direction of the coordinate axes depicted in FIG. 2B). That is, as the glass substrate 155 is transported the free end 162 of the glass substrate 155 may move away from its vertical orientation and rotate about the fixed end 160 a tilt angle a._t away from a vertical axis 156 that is parallel to the +/- Z axis of the coordinate axes depicted in the figure. This flapping phenomenon may become more pronounced when transporting the glass substrate 155 along the glass conveyance path 250 at higher speeds. Such flapping may cause the free end 162 of the glass substrate 155 to contact various structures positioned along the glass conveyance path 250, including BOD manufacturing process equipment positioned along the glass conveyance path 250, potentially resulting in the glass substrate 155 fracturing or other damage to the glass substrate 155. In particular, larger glass substrates 155 (e.g., having a length greater than or equal to about 1000 mm in the vertical direction) may be particularly susceptible to damage due to this flapping phenomenon.

[0037] Referring again to FIG. 2A, the non-contact glass substrate guiding apparatus

204 is provided to mitigate the above-described flapping phenomenon. Stated another way, the non-contact glass substrate guiding apparatus 204 may prevent or reduce movement of the free end 162 of the glass substrate 155 transverse to the glass conveyance path 250 and thereby prevent or reduce damage to the glass substrate 155 due to the flapping phenomenon. The non-contact glass substrate guiding apparatus 204 may include a communication path 221, a control unit 220, a glass detector 222, and one or more blower pairs 205 (e.g., first blower pair 206, second blower pair 208, and third blower pair 210 as depicted in FIG. 2A) positioned along the glass conveyance path 250.

[0038] The control unit 220 may be communicatively coupled to the one or more blower pairs 205 with communication path 221. The control unit 220 may include one or more processors and one or more memory modules. In the embodiments described herein, the memory modules may be non-transitory memory modules which include machine readable and executable instructions for controlling the one or more blower pairs 205. In particular, the instructions stored on the one or more memory modules, when executed by the processor, cause the processor to automatically activate and/or deactivate the one or more blower pairs 205.

[0039] Each of the one or more processors of the control unit 220 may be any device capable of executing machine readable instructions. Accordingly, each of the one or more processors may be a controller, an integrated circuit, a microchip, a computer, or any other computing device. The one or more processors are communicatively coupled to a

communication path 221 that provides signal interconnectivity between various components of the non-contact glass substrate guiding apparatus 204. Accordingly, the communication path 221 may communicatively couple any number of processors with one another, and allow the components coupled to the communication path 221 to operate in a distributed computing environment. Specifically, each of the components may operate as a node that may send and/or receive data. As used herein, the term "communicatively coupled" means that coupled components are capable of exchanging data signals with one another such as, for example, electrical signals via conductive medium, electromagnetic signals via air, optical signals via optical waveguides, and the like.

[0040] Accordingly, the communication path 221 may be formed from any medium that is capable of transmitting a signal such as, for example, conductive wires, conductive traces, optical waveguides, or the like. In some embodiments, the communication path 221 may facilitate the transmission of wireless signals, such as WiFi, Bluetooth, and the like. Moreover, the communication path 221 may be formed from a combination of mediums capable of transmitting signals. In one embodiment, the communication path 221 includes a combination of conductive traces, conductive wires, connectors, and buses that cooperate to permit the transmission of electrical data signals to components such as processors, memories, sensors, input devices, output devices, and communication devices. Accordingly, the communication path 221 may comprise a vehicle bus, such as for example a LIN bus, a CAN bus, a VAN bus, and the like. Additionally, it is noted that the term "signal" means a waveform (e.g., electrical, optical, magnetic, mechanical or electromagnetic), such as DC, AC, sinusoidal-wave, triangular-wave, square-wave, vibration, and the like, capable of traveling through a medium.

[0041] As noted above, the non-contact glass substrate guiding apparatus 204 may include a glass detector 222 communicatively coupled to the control unit 220. The glass detector 222 may be configured to output a signal indicative of the glass substrate 155 being located within a predetermined portion of the glass conveyance path 250 (e.g., within or proximate to the non-contact glass substrate guiding apparatus 204 and/or the BOD manufacturing process 200). When the glass detector 222 outputs the signal indicative of the glass substrate 155 being located within the predetermined portion of the glass conveyance path 250, the control unit 220 executes logic to selectively operate the one or more blower pairs 205. Similarly, the control unit 220 can execute logic to automatically deactivate the one or more pair of blowers when it is determined, based on the signal of the glass detector 222, that the glass substrate 155 is not located in the predetermined portion of the glass conveyance path 250. Accordingly, the glass detector 222 can be any detector capable of outputting a signal indicative of the location of the glass substrate 155 along the glass conveyance path 250. For example, the glass detector 222 may be a timer wherein, based on operating speeds of the conveyor 152 and other manufacturing equipment, the location of the glass substrate 155 along the conveyance path can be determined based on output signal of the timer. In other embodiments, the glass detector 222 may include, but is not limited to, an optical detector or the like, to optically detect the location of the glass substrate 155 along the glass conveyance path 250. In other embodiments there may be no glass detector 222. For example, the one or more blower pairs 205 may be manually controlled from a user interface of the control unit 220. In other embodiments, the one or more blower pairs 205 may automatically turn on when the conveyor 152 is operating.

[0042] FIG. 2A illustrates the non-contact glass substrate guiding apparatus 204 as including a first blower pair 206 and second blower pair 208 positioned downstream of the first blower pair 206. In some embodiments, a third blower pair 210 may be positioned downstream from the second blower pair 208. However, a greater or fewer number of blower pairs 205 may be present without departing from the scope of the present disclosure. For example, in some embodiments there may only be a single blower pair. In other

embodiments, there may be more than one blower pair (e.g., two blower pairs, three blower pairs, four blower pairs, etc.) The number of blower pairs may be based on a length of the BOD manufacturing process 200 through which the glass substrate 155 is conveyed along the glass conveyance path 250. The one or more blower pairs 205 may include any type of blower operable to direct a fluid stream (e.g., compressed dry air, compressed nitrogen gas, or the like) toward the glass conveyance path 250. For example, and not as a limitation, the one or more blower pairs 205 may include air knives, air nozzles, air gates, air slots, or similar such devices. In a particular embodiment, the one or more blowers are air knives that substantially adhere to the Coanda profile wherein the fluid stream exiting the air knife entrains surrounding air into the fluid stream, which may result in an amplification of the fluid stream. FIG. 3 generally illustrates this concept.

[0043] In particular, FIG. 3 illustrates a diffusive turbulent flow pattern of a fluid stream 211 produced by an example air knife 212 that may be used as a blower of the one or more blower pairs 205, wherein ambient fluid 213 is combined into the fluid stream 211 in adherence with the Coanda profile discussed above. The fluid stream 211 experiences greater diffusion as the distance increases from the outlet of the air knife 212. Based on modeling of known standard air knife performance exhibiting the illustrated diffusive turbulent flow pattern shown in FIG. 3, such as the Exair© Standard Air knife available from the Exair Corporation, Cincinnati, Ohio, guiding torque acting on the surface of the glass substrate 155 can be estimated based on modeling of the diffusive turbulent flow pattern.

[0044] For example, the Exair© Standard Air knife with a 0.002 inch thick shim installed in the air outlet of the air knife has the following performance parameters:

Table 1 : Exair© Standard Air Knife Performance

[0045] Using the fluid flow equation for open-jet turbulent flow (Equation 1):

Equation 1

where u is flow speed, r is position relative to the r-axis , x is position along the x-axis. and C is a constant which can be derived from the above equation using the above known factors of the Exair© Standard Air knife. The flow force can then be estimated as a flow pressure multiplied by the area of the glass substrate, and guiding torque can be calculated from the estimated flow force, based on parameters that will be described in greater detail herein including installation height (H_n) of the one or more blowers pairs 205, nozzle distance (D_n) of the one or more blower pairs 205 from major surfaces of the glass surface, and the blowing angle (q_h) of the fluid stream from the one or more blower pairs 205.

[0046] Referring again to FIGS. 2A and 2B, and in particular to FIG. 2B, each of the one or more blower pairs 205 may include a first blower positioned along the glass conveyance path and a second blower positioned along the glass conveyance path opposite the first blower. For example, FIG. 2B illustrates the first blower pair 206 as having a first blower 206a positioned along the glass conveyance path 250 and a second blower 206b positioned along the glass conveyance path 250 opposite the first blower 206a. The first blower 206a is positioned along the glass conveyance path 250 so as to direct a first fluid stream 21 la toward the lower extent of the glass conveyance path 250 and the second blower 206b is positioned along the glass conveyance path 250 so as to direct a second fluid stream 21 lb toward the lower extent of the glass conveyance path 250. The position, orientation, and blowing force of the fluid streams 21 la, 21 lb of the first blower 206a and the second blower 206b are equal and opposite to each other on either side of the glass conveyance path 250. Accordingly, when the free end 162 of the glass substrate 155 passes between the first and second blowers, the first and second fluid streams 21 la, 21 lb contact only a portion of a first side and a second side of the glass substrate, respectively. In this manner, a guiding torque can be provided to the free end 162 of the glass substrate 155 by the first and second fluid streams 21 la, 21 lb thereby preventing the flapping phenomenon described herein. Each subsequent blower pair (e g., the second blower pair 208, the third blower pair 210, etc.) may be similarly oriented. Accordingly, description of the first and second blowers 206a, 206b in regards to the first blower pair 206 apply equally to each of the one or more blower pairs 205.

[0047] The guiding torque 215 provided to the free end 162 of the glass substrate 155 by the first and second blowers 206a, 206b may be dependent on several parameters including the installation height (H_n), the nozzle distance (D_n), the blowing angle (0_n), and the operating flow rates of the first and second blowers 206a, 206b. Each of these parameters may be adjusted based on the dimensions of the glass substrate 155 being conveyed along the glass conveyance path 250, the desired conveyance speed, the natural torque experienced by the glass substrate 155 due to gravity, and the like. Each of the above parameters may also be limited based on the BOD manufacturing process 200 to which they are applied. For example, lamination processing, as will be described in the examples, may not rely on nozzle distance (D_n) or installation height (H_n) as the structure of the lamination process may limit placement of the first and second blowers 206a, 206b.

[0048] Installation height (H_n) refers to the vertical position at which the first and second blowers 206a, 206b are installed on either side of the glass conveyance path 250. The installation height (H_n) is determined relative to the fixed end 160 of the glass substrate 155 (i.e., where the one or more conveyor clamps 153 coupled the glass substrate 155 to the conveyor 152 shown in FIG. 2A). Accordingly, the installation height (H_n) may be any height which allows the first and second blowers 206a, 206b to provide a guiding torque to the free end 162 of the glass substrate 155. The installation height (H_n) may be dependent on a number of factors. In particular, the installation height (H_n) may be limited by the BOD manufacturing process 200 with which the one or more blower pairs 205 is used in conjunction with (e.g., certain BOD manufacturing processes 200 may have limited space for mounting the one or more blower pairs 205). In some embodiments, the installation height (H_n) places the first and second blowers 206a, 206b adjacent to the free end 162 of the glass substrate 155. However, other installation heights (H_n) are contemplated and possible depending on the size of the glass substrate 155. While it is contemplated that the present apparatus may be applicable to glass substrates of any size, some example sizes include glass substrates having the following example dimensions: 1240 mm x 1350 mm, 1360 mm x 1550 mm, 1550 mm x 1360 mm, 1880 mm x 1520 mm, and the like. Based on the above examples, in some embodiments, the installation height (H_n) may be from about 0 mm to about 1500 mm. However, it is noted that the smaller the installation height (H_n), the larger the blowing angle (q_h) and nozzle distance (D_n) so that guiding torque can be provided to the free end 162 of the glass substrate 155.

[0049] The nozzle distance (D_n) is the distance of the first blower 206a and the second blower 206b of the one or more blower pairs 205 from the respective major surfaces of the glass substrate 155 when the glass substrate 155 is parallel with the vertical plane (i.e., parallel to the X-Z substrate of the coordinate axes depicted in the figures and indicated by vertical axis 156. As with the installation height (H_n), the nozzle distance (D_n) may be dependent on a number of factors, including the BOD manufacturing process 200 with which the one or more blower pairs 205 is used in conjunction with. Accordingly, the nozzle distance (D_n) may be any distance which allows the one more blower pairs 205 to provide a guiding torque 215 to the free end 162 of the glass substrate 155. For example, too large a distance may prevent the fluid streams of the one or more blower pairs 205 from adequately contacting the glass substrate 155 to provide a guiding torque 215. In some embodiments, the nozzle distance (D_n) is from about 100 mm to about 250 mm. However, it should be understood that other nozzle distances (D_n) are contemplated and possible.

[0050] The blowing angle (q_h) is the angle at which the first and second fluid streams

21 la, 21 lb are directed toward the glass conveyance path 250 relative to the horizontal axis (y). The blowing angle (q_h) may be any angle such that the first and second fluid streams 21 la, 21 lb are capable of providing a guiding torque 215 to the free end 162 of the glass substrate 155 traveling along the glass conveyance path 250. In some embodiments, the blowing angle (q_h) is a non-zero angle relative to a horizontal axis (y). In some

embodiments, the blowing angle (q_h) is a non-zero angle from about 10 degrees to about 70 degrees below the horizontal axis (e.g., 45 ± 0.5 degrees, 60 ± 0.5 degrees).

[0051] The guiding torque per inch of blower pair to prevent the flapping

phenomenon for a particular glass substrate may be modeled using the following equation (Equation 2):

Equation 2

where M_t is the guiding torque Aί, is the natural torque acting the glass substrate due to gravity, target drag is the flow drag force acting on glass substrate, current drag is the flow drag force acting on a baseline glass substrate, target acceleration is the acceleration of the glass substrate, current acceleration is the acceleration of the baseline glass substrate, target stiffness is the stiffness of the glass substrate, and current stiffness is the stiffness of the of the baseline glass substrate. Therefore, depending on the conveying settings and the parameters of the glass substrate, the guiding torque to prevent the flapping phenomenon can be estimated. Accordingly, the various parameters of the one or more blower pairs including the installation height (H_n), the nozzle distance (D_n), the blowing angle (q_h) can be adjusted to provide the estimated guiding torque.

[0052] FIG. 4 illustrates a flow diagram of one method 300 of transporting a glass substrate 155 using the glass substrate conveyance assembly 151 described herein. Though the various steps of the method 300 are shown as having a particular order, the method 300 could be performed with a different ordering of steps or with more or fewer steps without departing from the scope of the present disclosure. The method 300 includes conveying the glass substrate 155 (step 302). As described above, such conveyance may be horizontal along the glass conveyance path 250 with the glass substrate 155 in a substantially vertical orientation. The method 300 further includes activating the one or more blower pairs 205 (step 306). Activating the one or more blower pairs 205 results in a first fluid stream 21 la from a first blower 206a being incident against a first side 158 (indicated in FIG. 5 A) of the glass substrate 155 and a second fluid stream 21 lb from a second blower 206b being incident against a second side 159 (also indicated in FIG. 5A) of the glass substrate 155. As noted herein, the first blower 206a and the second blower 206b are positioned opposite one another along the glass conveyance path 250 and can provide equal and opposite fluid streams 21 la, 21 lb directed toward the glass conveyance path. The first and second fluid streams 21 la,

21 lb from the first blower 206a and the second blower 206b can accordingly provide a guiding torque to the free end 162 of the glass substrate 155 and prevent movement of the free end 162 of the glass substrate 155 in a direction transverse to the glass conveyance path 250. FIGS. 5 A and 5B illustrate this phenomenon.

[0053] In particular, FIG. 5 A illustrates the glass substrate 155 experiencing a flapping phenomenon wherein the free end 162 of the glass substrate 155 has rotated transverse to the glass conveyance path 250 by the tilt angle (a_t). The free end 162 of the glass substrate 155 is thus positioned closer to one of the first blower 206a and the second blower 206b, in this case the first blower 206a. When the free end 162 of the glass substrate 155 is positioned closer the first blower 206a or the second blower 206b, the flow force acting on both sides of the glass substrate 155 is not balanced. That is, the first fluid stream 21 la provides a greater force to a first side of the glass substrate 155 than the second fluid stream 21 lb provides to a second side of the glass substrate 155 due to flow leakage near the bottom of the glass substrate 155. Stated another way, a portion of the second fluid stream 21 lb is not directed against the glass substrate 155 at the free end 162 of the glass substrate 155. Due to the greater force on one side of the glass substrate 155 provided by the first fluid stream 21 la, a guiding torque 215 is introduced against the first side 158 of the glass substrate 155 at the free end 162 to pivot the glass substrate 155 back to the vertical orientation, as shown in FIG. 5B where the first and second fluid streams 21 la, 21 lb on either side of the glass substrate 155 are balanced.

[0054] Referring again to FIG. 4, in some embodiments, the method 300 may further include a step 304 of determining the location of the glass substrate 155 along the glass conveyance path 250. As noted above, determining the location of the glass substrate 155 may be accomplished with use of a glass detector 222 configured to output a signal indicative that the glass substrate 155 is located within a predetermined portion of the glass conveyance path 250. For example, the glass detector 222 may be a timer, wherein based on the output signal of the timer, the control unit 220 executes logic to determine whether or not the glass substrate 155 is in a predetermined portion of the glass conveyance path 250. Based on the signal from the glass detector 222 the control unit 220 can automatically activate the one or more blower pairs 205 (step 306) when, based on the signal of the glass detector 222, the glass substrate 155 is located within a predetermined portion along the glass conveyance path 250. ln some embodiments, the control unit 220 can automatically deactivate the one or more blower pairs 205 (step 308), when, based on the signal of the glass detector 222, the glass is not located within the predetermined portion along the glass conveyance path 250. In some embodiments, the one or more blowers 205 may be always activated when the glass substrate 155 is conveyed along the glass conveyance path irrespective of where the glass substrate is positioned along the glass conveyance path 250. In alternative embodiments, the one or more blower pairs 205 may be manually activated and/or deactivated. Examples

[0055] Example 1 - Guidance Through a Built-In Weight Scale (“BIWS”) and

Thickness Gauge

[0056] FIG. 6A illustrates a side view of a portion of a BIWS and thickness gauge

Station 400, a BOD manufacturing process, having a frame 402 and a non-contact glass substrate guiding apparatus 204 mounted on the frame 402 along the glass conveyance path 250, when viewed along the +X direction of the coordinate axes depicted. FIG. 6B illustrates a cross section of the BIWS and thickness gauge Station 400 when viewed from above along the -Z direction of the coordinate axes depicted. FIG. 6C illustrates a cross-section of the BIWS and OLTG Station 400 when viewed from a centerline of the glass conveyance path in the +X direction of the coordinate axes depicted in the figures. To enter the BIWS and OLTG station 400, the glass substrate 155 is conveyed along the glass conveyance path 250 between narrowing opposing portions (e.g., 406 and 404) of the frame 402 (FIG. 6B). In manufacturing processes without a non-contact glass substrate guiding apparatus 204, when the glass substrate 155 experiences the flapping phenomenon described herein shown in FIG. 2B, the free end 162 of the glass substrate 155 can contact either portion 404, 406 of the frame 402 which may lead to damage to the glass substrate 155. Accordingly, under traditional conveyance techniques (i.e., without use of the non-contact glass substrate guiding apparatus 204 described herein) the conveyance speed of the glass substrate 155 along the conveyor 152 may be slowed so as to prevent substantial flapping of the free end 162 of the glass substrate 155 as the glass substrate 155 travels through the BIWS and OLTG station 400.

[0057] The non-contact glass substrate guiding apparatus 204 used in conjunction with the BIWS and OLTG station 400 may include a first blower pair 206, a second blower pair 208, and a third blower pair 210 mounted to the frame 402 of the BIWS and OLTG station 400. The pairs of blowers may be mounted to the frame 402 using any coupling techniques suitable for mounting the pairs of blowers to the frame 402 (e.g., fasteners, adhesives, clamps, etc.). Each pair of blowers includes a first blower (e.g., 206a, 208a, 2l0a) and a second blower (e.g., 206b, 208b, and 2l0b.) The pairs of blowers may be equally spaced from one another along the conveyance path such that each pair of blowers are equidistantly spaced from one another or the pairs of blowers may be unequally spaced along the glass conveyance path. In this example, each of the blowers are 6 inch (i.e., 152.4 mm) long air knives with a flow rate of about 200 liter/min - to about 400 liters/ min (e g., about 260 to about 370 liters/min) under a pressure of about 20 psig. In determining the guiding torque as provided by Equation 2, above, the baseline glass substrate had a vertical length of 1880 mm, a width of 1520 mm, a thickness of 5 mm, and a natural torque (M„) of 0.045 N- m/inch of blower pair length, a conveying speed of 0.5 m/s and an acceleration of 1 m/s².

[0058] FIG. 6C illustrates a cross-sectional view of the first blower pair 206 mounted on the BIWS and OLTG station 400. In this example, the nozzle distance (D_n) was set at 200 mm and the blowing angle (q_h) was fixed at about 45 degrees below the horizontal (Y), and the installation height (H_n), illustrated in FIG. 2B) was varied to provide an adequate guiding torque sufficient to control the flapping phenomenon of glass substrate samples. The samples tested had the following dimensions given in vertical length by horizontal width of the major surface of the sample: Sample 1 - 1240 mm x 1350 mm; Sample 2 - 1360 mm x 1550 mm; Sample 3 - 1550 mm x 1360 mm; and Sample 4 - 1880 mm x 1520 mm). Each of the samples had thickness of about 0.25 mm. The guiding torque (in newton-meter per inch of blower pair length) for preventing the flapping phenomenon for each size of glass substrate and the range of installation heights (H_n) are provided in Table 2.

Table 2: Results of Testing for non-contact glass substrate guiding apparatus as applied to BIWS and OLTG station

[0059] It was also found that conveying speeds could be increased by up to about 1.5 times the conventional conveying speed (i.e., the conveying speed without the non-contact glass substrate guiding apparatus 204) with an increase in acceleration of up to 1.3 times the conventional acceleration of the glass substrate without experiencing the flapping

phenomenon. Under some conditions it was found that the conveying speeds could be increased by up to 1.8 times that of the conventional conveying speed. This increase in conveying speed may result in a cycle time reduction of 15% or greater.

[0060] Example 2 - Guidance Through a Lamination (LAM) Assembly

[0061] FIGS. 7A and 7B illustrate a non-contact glass substrate guiding apparatus 204 used in conjunction with a LAM assembly 500. The LAM assembly 500 includes a first moveable frame member 502 and second moveable frame member 506. A first roller 508 may be mounted to the first moveable frame member 502 and a second roller 510 may be mounted to the second moveable frame member 506. In operation, the glass substrate 155 may be conveyed on the conveyor 152 (shown in FIG. 2A) along the glass conveyance path 250 to be positioned between the first and second rollers 508, 510. The first and second moveable frame members 502, 506 may then move toward one another in the Y direction as indicated by the illustrated coordinate axes into the glass conveyance path 250 such that a glass substrate 155 traveling there between can be contacted by the first and second rollers 508, 510, detached from the conveyor 152 (shown in FIG. 2A), and passed vertically through the first and second rollers 508, 510 to coat the glass substrate 155.

[0062] The non-contact glass substrate guiding apparatus 204 mounted on the LAM assembly 500 may include a first blower pair 206, a second blower pair 208, and a third blower pair 210. The pairs of blowers may be mounted to the first and second moveable frame members 502, 506 using any coupling techniques suitable for mounting the pairs of blowers to the first and second moveable frame members 502, 506 (e.g., fasteners, adhesives, clamps, etc.). Each pair of blowers includes a first blower (e.g., 206a, 208a, and 2l0a) and a second blower (e.g., 206b, 208b, and 2l0b.) The pairs of blowers may be equally spaced from one another along the conveyance path or unequally spaced. In this example, each of the blowers are 18 inch (457.2 mm) long air knives with a flow rate of about 350 liter/min to about 450 liters/min under a pressure of about 10 psig. In this case, a blowing angle of about 60 degrees was found to be adequate to supply a guiding torque to the free end 162 of the glass substrate 155 to suppress movement of the glass substrate 155 transverse to the conveyance path.

[0063] It should now be understood that embodiments of the present disclosure are directed to non-contact glass substrate guiding apparatuses and to methods of transporting a glass substrate wherein a flapping phenomenon experienced at a free end of the glass substrate is suppressed and/or prevented. Such apparatuses include at least a first blower positioned along a glass conveyance path and a second blower positioned along the glass conveyance path opposite the first blower. A glass substrate can be transported horizontally with the glass substrate in a vertical orientation along the glass conveyance path through a variety of bottom-of-draw manufacturing processes and equipment. The first blower can be positioned along the glass conveyance path so as to direct a first fluid stream toward lower extent of the glass conveyance path and the second blower can be positioned along the glass conveyance path so as to direct a second fluid stream toward the lower extent of the glass conveyance path. The first and second fluid streams provided by the first and second blowers are configured to provide a guiding torque to a glass substrate conveyed along the glass conveyance path to prevent movement of the of the glass substrate transverse to the glass conveyance path. Accordingly, when a glass substrate is being transported along the glass conveyance path the guiding torque provided by the first and second blowers can guide the glass substrate so that it does make unwanted contact with bottom-of-draw equipment arranged along the glass conveyance path. Moreover, by preventing and/or reducing the flapping phenomenon, conveyance speeds can be increased and cycle times may be reduced. In this manner, the overall yield of BOD manufacturing processes can be improved from by 80%-92%.

[0064] It is noted that the terms "substantially" and "about" may be utilized herein to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. These terms are also utilized herein to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue. [0065] While particular embodiments have been illustrated and described herein, it should be understood that various other changes and modifications may be made without departing from the spirit and scope of the claimed subject matter. Moreover, although various aspects of the claimed subject matter have been described herein, such aspects need not be utilized in combination. It is therefore intended that the appended claims cover all such changes and modifications that are within the scope of the claimed subject matter.

Claims

What is claimed is:

1. A method of transporting a glass substrate, comprising:

conveying the glass substrate horizontally along a glass conveyance path in a vertical orientation, wherein the glass substrate comprises a fixed end defining a top of the glass substrate and a free end defining a bottom of the glass substrate;

blowing a first fluid stream against only a portion of a first side of the glass substrate with a first blower;

blowing a second fluid stream against only a portion of a second side of the glass substrate with a second blower positioned opposite the first blower, wherein the first blower and the second blower direct a guiding torque to the free end of the glass substrate and suppress movement of the free end of the glass substrate in a direction transverse to the glass conveyance path.

2. The method of claim 1, wherein the fixed end is coupled to a conveyor with one or more conveyor clamps.

3. The method of claim 1, wherein the first blower and the second blower direct the first and second fluid streams toward the glass substrate at a non-zero angle relative to a horizontal axis.

4. The method of claim 1, wherein the first and second blowers direct the first and second fluid streams toward the glass substrate at an angle relative to a horizontal axis from about 10 degrees to about 70 degrees below the horizontal axis.

5. The method of claim 1, wherein the glass substrate comprises a leading edge extending between the fixed end and the free end and a conveyance direction along the glass conveyance path is perpendicular to the leading edge.

6. The method of claim 1, wherein the first and second blowers comprise air knives.

7. The method of claim 1, further comprising:

determining a location of the glass substrate along the glass conveyance path;

activating the first and second blowers when the glass substrate is located in a predetermined portion of the glass conveyance path; and

deactivating the first and second blowers when the glass substrate is not located in the predetermined portion of the glass conveyance path.

8. A non-contact glass substrate guiding apparatus, comprising: a first blower positioned along a glass conveyance path, wherein the glass conveyance path is defined at an upper extent by a conveyor operable to horizontally convey a glass substrate in a vertical orientation such that one end of the glass substrate conveyed along the glass conveyance path is coupled to the conveyor and a free end of the glass substrate conveyed along the glass conveyance path is unrestrained to the conveyor at a lower extent of the glass conveyance path; and

a second blower positioned along the glass conveyance path opposite the first blower, wherein:

the first blower is positioned along the glass conveyance path so as to direct a first fluid stream toward the lower extent of the glass conveyance path;

the second blower is positioned along the glass conveyance path so as to direct a second fluid stream toward the lower extent of the glass conveyance path; and

the first and second fluid streams are configured to contact only a portion of a first side and a second side of the glass substrate, respectively, and direct a guiding torque to the free end of the glass substrate conveyed along the glass conveyance path to suppress movement of the free end of the glass substrate transverse to the glass conveyance path.

9. The non-contact glass substrate guiding apparatus of claim 8, wherein the first and second blowers direct the first and second fluid streams toward the lower extent of the glass conveyance path at a non-zero angle relative to a horizontal axis.

10. The non-contact glass substrate guiding apparatus of claim 8, wherein the first and second blowers direct the first and second fluid streams toward the lower extent of the glass conveyance path at an angle relative to a horizontal axis from about 10 degrees to about 70 degrees below the horizontal axis.

11. The non-contact glass substrate guiding apparatus of claim 8, wherein the first and second blowers comprise air knives.

12. The non-contact glass substrate guiding apparatus of claim 8, further comprising:

a control unit communicatively coupled to the first and second blowers; and

a glass detector communicatively coupled to the control unit and configured to output a signal indicative of the glass substrate positioned in a predetermined portion of the glass conveyance path, wherein the control unit executes logic to automatically activate the first and second blowers when it is determined, based on the signal of the glass detector, that the glass substrate is located in the predetermined portion of the glass conveyance path.

13. The non-contact glass substrate guiding apparatus of claim 12, wherein the control unit executes logic to automatically deactivate the first and second blowers when it is determined, based on the signal of the glass detector, that the glass substrate is not located in the predetermined portion of the glass conveyance path.

14. The non-contact glass substrate guiding apparatus of claim 12, wherein:

the first and second blowers comprise a first blower pair;

the non-contact glass substrate guiding apparatus further comprises a second blower pair positioned downstream of the first blower pair along the glass conveyance path; and

the second blower pair comprise a first blower positioned along the glass conveyance path and a second blower positioned along the glass conveyance path opposite the first blower of the second blower pair.

15. A glass substrate conveyance assembly, comprising:

a conveyor defining an upper extent of a glass conveyance path, the conveyor comprising a clamp, wherein the conveyor is operable to convey a glass substrate horizontally along the glass conveyance path in a vertical orientation such that one end of the glass substrate conveyed along the glass conveyance path is coupled to the conveyor by the clamp and a free end of the glass substrate conveyed along the glass conveyance path is unrestrained to the conveyor at a lower extent of the glass conveyance path; and

a non-contact glass substrate guiding apparatus, comprising:

a first blower positioned along the glass conveyance path; and

16. The glass substrate conveyance assembly of claim 15, wherein the first blower and the second blower of the non-contact glass substrate guiding apparatus direct the first and second fluid streams toward the lower extent of the glass conveyance path at an angle relative to a horizontal axis

17. The glass substrate conveyance assembly of claim 15, wherein the first blower and the second blower of the non-contact glass substrate guiding apparatus direct the first and second fluid streams toward the lower extent of the glass conveyance path at an angle relative to a horizontal axis from about 10 degrees to about 70 degrees below the horizontal axis.

18. The glass substrate conveyance assembly of claim 15 wherein the first and second blowers of the non-contact glass substrate guiding apparatus comprise air knives.

19. The glass substrate conveyance assembly of claim 15, further comprising:

a control unit communicatively coupled to the first and second blowers of the non-contact glass substrate guiding apparatus; and

a glass detector communicatively coupled to the control unit and configured to output a signal indicative of the glass substrate located in a predetermined portion of the glass conveyance path, wherein the control unit executes logic to automatically activate the first and second blowers when it is determined, based on the signal of the glass detector, that the glass substrate is located in the predetermined portion of the glass conveyance path.

20. The glass substrate conveyance assembly of claim 19, wherein the control unit executes logic to automatically deactivate the first and second blowers when it is determined, based on the signal of the glass detector, that the glass substrate is not located in the predetermined portion of the glass conveyance path.