Glass Manufacturing Equipment

Abstract

The separation device for a glass manufacturing apparatus includes a frame assembly having an upper frame portion and a lower frame portion, a carriage assembly, and a drive assembly including a screw shaft coupled to the carriage assembly. The glass manufacturing apparatus further includes a bellows extending over the screw shaft between the lower frame portion and the carriage assembly, and a bellows cover extending over the bellows.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of priority under 35 U.S.C. § 119 of U.S. Provisional Application No. 63 / 428,182, filed November 28, 2022, the contents of which are incorporated by reference in their entirety.

[0002] The present disclosure relates to a glass manufacturing apparatus for producing a glass ribbon. More specifically, the glass manufacturing apparatus includes a glass separating device for separating glass sheets from a glass ribbon, the glass separating device including a screw shaft, a protective bellows disposed around the screw shaft, and a bellows cover disposed around the protective bellows. [Background technology]

[0003] For example, it is known to produce glass ribbons by a downdraw process, such as a fusion downdraw process. Typically, the glass ribbon is continuously drawn from a former. Glass sheets can be separated from the continuously moving glass ribbon by a glass separating device. The glass separating device can include a reciprocating carriage assembly that periodically moves downward with the glass ribbon, the reciprocating carriage assembly including a scoring device that moves transversely along the carriage assembly and scores the glass ribbon during its downward movement. Once scoring is complete, the carriage assembly is moved upward to await the start of another cycle. Summary of the Invention

[0004] The separation device includes a screw shaft and a nut assembly, the screw shaft coupled to a motor configured to rotate the screw shaft. The nut is coupled to a carriage assembly and engaged with the screw shaft. Rotation of the screw shaft causes the nut assembly, and therefore the carriage assembly, to move laterally along the rotating screw shaft, thereby providing downward and upward reciprocating motion of the carriage assembly. To minimize friction, the screw shaft and / or the nut assembly may be lubricated with a lubricant, such as oil or grease. The lubricant may include one or more petroleum products. In addition, the glass ribbon scoring and separation process may generate glass debris (e.g., glass chips) that may interfere with the proper operation of the screw shaft and nut assembly. Therefore, a bellows may be positioned around the screw shaft such that the screw shaft is protected within the passage of the bellows. In embodiments, the bellows may not be a unitary structure and may instead be formed from multiple cut pieces assembled, e.g., connected, to form the bellows.

[0005] Areas of the separation device may be heated to control the cooling of the glass ribbon and reduce stress within the glass ribbon. This heating may vaporize the lubricant, which may then leak through the bellows seams where the individual pieces comprising the bellows are connected. The vaporized lubricant may condense on the glass ribbon and contaminate it, thereby rendering the glass ribbon and any glass sheets separated from it unsuitable for use. A bellows cover may be disposed around the bellows to provide additional protection for the screw shaft and bellows and to reduce the evaporation of the lubricant. The bellows cover may reduce the temperature of the environment around the bellows, for example, inside and / or outside the bellows, thereby reducing the evaporation of the lubricant.

[0006] Accordingly, in a first aspect, a glass manufacturing apparatus is disclosed that includes a former configured to form a glass ribbon and a separating apparatus configured to separate the glass ribbon. The separating apparatus may include a frame assembly that includes an upper frame portion and a lower frame portion, a carriage assembly that includes a scoring device configured to score the glass ribbon, a drive assembly that includes a screw shaft extending between the upper and lower frame portions, the screw shaft coupled to a drive motor configured to orbit the screw shaft, a nut assembly that is coupled to the carriage assembly and engages with the screw shaft such that rotation of the screw shaft by the drive motor moves the carriage assembly along the screw shaft between the upper and lower frame portions, and a bellows cover that extends over the screw shaft between the lower frame portion and the carriage assembly, e.g., a bellows cover that extends over the bellows between the lower frame portion and the carriage assembly.

[0007] In a second embodiment, the bellows of the first embodiment may include aluminum.

[0008] In a third aspect, the bellows of any one of the first or second aspects may comprise a polymer.

[0009] In a fourth aspect, the bellows cover of any one of the first to third aspects may include a fabric, for example, a woven fabric, a knitted fabric, or a felt fabric.

[0010] In a fifth aspect, the fabric of the fourth aspect may comprise glass fibre, for example a glass fibre fabric.

[0011] In a sixth aspect, the glass manufacturing apparatus of any one of the first to fifth aspects may include a first clamp assembly connecting a first end of the bellows cover to the carriage assembly, and the first clamp assembly includes a first vacuum line extending between the vacuum source and the first clamp assembly such that the vacuum source is in fluid communication with the space between the bellows and the bellows cover.

[0012] In a seventh aspect, the glass manufacturing apparatus of the sixth aspect may further include a second clamp assembly coupling a second end of the bellows cover to the lower frame portion, the second clamp assembly including a second vacuum line extending between the vacuum source and the second clamp assembly such that the vacuum source is in fluid communication with the space between the bellows and the bellows cover.

[0013] In an eighth aspect, the glass manufacturing apparatus of any one of the first to fifth aspects may include a vacuum ring, the vacuum ring including a first ring wall portion, a second ring wall portion inside the first ring wall portion and spaced a first gap from the first ring wall portion and spaced a second gap from the screw shaft, a bellows cover coupled to the first ring wall portion, and a bellows coupled to the second ring wall portion, a first vacuum line coupled to the vacuum ring and in fluid communication with the first gap, and a second vacuum line coupled to the vacuum ring and in fluid communication with the second gap, wherein the first gap is not in fluid communication with the second gap.

[0014] In a ninth embodiment, the vacuum ring of the eighth embodiment is a first vacuum ring, the first vacuum ring coupling the first end of the bellows cover to the lower frame portion.

[0015] In a tenth aspect, the drive assembly of any one of the first to ninth aspects may include a ball screw.

[0016] Both the foregoing general description and the following detailed description present embodiments intended to provide an overview or framework for understanding the nature and features of the embodiments disclosed herein. The accompanying drawings are included to provide a further understanding, and are incorporated in and constitute a part of this specification. The drawings illustrate various embodiments of the present disclosure and, together with the description, explain its principles and operation. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a schematic diagram of an exemplary glass manufacturing apparatus. [Figure 2] 1 is an elevational view of an exemplary glass separation apparatus including a drive assembly having a screw shaft, a protective bellows, and a bellows cover. [Figure 3] FIG. 10 is an elevated side view of a clamping device used to secure a bellows cover around a screw shaft and associated bellows. [Figure 4] FIG. 10 is a cross-sectional view of a portion of a bellows cover showing a formed wire attached to an end of the bellows cover. [Figure 5] 1 is a perspective view of an exemplary restraining clamp configured to hold a bellows cover to a clamping device. FIG. [Figure 6] FIG. 10 is a cross-sectional top view of a vacuum ring in a plane perpendicular to the screw shaft for coupling a bellows and associated bellows cover around the screw shaft. [Figure 7] FIG. 7 is a cross-sectional side view of the vacuum ring of FIG. 6. DETAILED DESCRIPTION OF THE INVENTION

[0018] Reference will now be made in detail to the 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.

[0019] As used herein, the term "about" means that amounts, sizes, formulas, parameters, and other quantities and properties are not, and need not be, exact and may be approximate and / or larger or smaller, as desired, to reflect tolerances, conversion factors, rounding, measurement error, etc., as well as other factors known to those of ordinary skill in the art.

[0020] 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.

[0021] Directional terms used herein, such as up, down, right, left, front, back, top, and bottom, are for reference only as depicted in the figures and are not intended to imply absolute orientation.

[0022] Unless otherwise expressly stated, no particular order or orientation of the components of the device is intended to be inferred in any respect, and this is true for any possible implicit basis for interpretation, including logical matters relating to the order of components or the orientation of components, the apparent meaning derived from grammatical construction or punctuation, and the number or type of embodiments described herein.

[0023] As used herein, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Thus, for example, reference to "one (a) element" includes aspects having two or more such elements unless the context clearly dictates otherwise.

[0024] The words "exemplary" and "example," or various variations thereof, are used herein to mean serving as an example, instance, or illustration. Any aspect or design described herein as "exemplary" or "example" is not necessarily to be construed as preferred or advantageous over other aspects or designs. Furthermore, examples are provided merely for purposes of clarity and understanding and are not meant to limit or restrict in any way the subject matter of this disclosure, or relevant portions thereof. It will be appreciated that numerous additional or alternative examples of varying scope could be presented but have been omitted for purposes of brevity.

[0025] As used herein, the terms "comprising" and "including," and variations thereof, unless otherwise indicated, are intended to be synonymous and open-ended. The list of elements following the transitional phrases "comprising" and "including" is a non-exclusive list, such that there may be other elements than those specifically listed.

[0026] As used herein, the terms "substantial," "substantially," and variations thereof are intended to note that a described characteristic is equal or nearly equal to a value or description. For example, a "substantially planar" surface is intended to describe a surface that is planar or nearly planar. Furthermore, "substantially" is intended to describe two values ​​that are equal or nearly equal. In some embodiments, "substantially" can describe values ​​that are within about 10% of each other, such as within about 5% of each other or within about 2% of each other.

[0027] An exemplary glass manufacturing apparatus 10 is shown in Figure 1. In some embodiments, the glass manufacturing apparatus 10 can include a glass melting furnace 12 including a melting tank 14. In addition to the melting tank 14, the glass melting furnace 12 can optionally include one or more additional components, such as heating elements (e.g., combustion burners and / or electrodes) configured to heat the raw materials and convert the raw materials into molten glass. For example, the melting tank 14 can be an electrically boosted melting tank, in which energy is applied to the raw materials via combustion burners and by direct heating, such that an electric current flows through the raw materials, thereby adding energy by Joule heating of the raw materials.

[0028] In further embodiments, the glassmelting furnace 12 may include other thermal management devices (e.g., insulating components) that reduce heat loss from the melting tank. In still further embodiments, the glassmelting furnace 12 may include electronic and / or electromechanical devices that facilitate melting of the raw materials into a glass melt. The glassmelting furnace 12 may include support structures (e.g., support chassis, support members, etc.) or other components.

[0029] The melting tank 14 can be formed from a refractory ceramic material, such as a refractory ceramic material comprising alumina or zirconia, although the refractory ceramic material can include other refractory materials, such as yttrium (e.g., yttria, yttria-stabilized zirconia, yttrium phosphate), zircon (ZrSiO), or alumina-zirconia-silica, or even chromium oxide, either instead of or in any combination. In some examples, the melting tank 14 can be constructed from refractory ceramic bricks.

[0030] In some embodiments, the glass melting furnace 12 may be incorporated as a component of a glass manufacturing apparatus configured to produce glass articles, such as glass ribbons, while in further embodiments, the glass manufacturing apparatus may be configured to form other glass articles, such as, but not limited to, glass rods, glass tubes, glass envelopes (e.g., glass envelopes for lighting devices, e.g., light bulbs), and glass lenses, although many other glass articles are contemplated. In some examples, the melting furnace may be included in a glass manufacturing apparatus, including a slot draw apparatus, a float bath apparatus, a downdraw apparatus (e.g., a fusion downdraw apparatus), an updraw apparatus, a press apparatus, a rolling mill apparatus, a tube draw apparatus, or any other glass manufacturing apparatus that would benefit from the present disclosure. By way of example, FIG. 1 schematically illustrates a glass melting furnace 12 as a component of a fusion downdraw-style glass manufacturing apparatus 10 for fusion drawing a glass ribbon into individual glass sheets for subsequent processing or rolling the glass ribbon onto spools.

[0031] Glass manufacturing system 10 may optionally include upstream glass manufacturing equipment 16 positioned upstream of melting tank 14. In some examples, a portion or all of upstream glass manufacturing equipment 16 may be incorporated as part of glass melting furnace 12.

[0032] As shown in the embodiment illustrated in FIG. 1 , the upstream glass manufacturing apparatus 16 can include a raw material storage bin 18, a raw material delivery device 20, and a motor 22 connected to the raw material delivery device 20. The raw material storage bin 18 can be configured to store a quantity of raw material 24, which can be fed into the melting tank 14 of the glass melting furnace 12 via one or more feed ports, as indicated by arrow 26. The raw material 24 typically includes one or more glass-forming metal oxides and one or more modifiers. In some examples, the raw material delivery device 20 can be powered by the motor 22 to deliver a predetermined amount of raw material 24 from the raw material storage bin 18 to the melting tank 14. In a further example, the motor 22 can power the raw material delivery device 20 to introduce the raw material 24 at a controlled rate based on a level of molten glass sensed downstream from the melting tank 14 relative to the direction of molten glass flow. The raw material 24 in the melting tank 14 can then be heated to form molten glass 28. Typically, in the initial melting step, the raw material is added to the melting tank as fine particles, for example, as various "sands." The raw material 24 may also include waste glass (i.e., cullet) from previous melting and / or forming operations. A combustion burner is typically used to initiate the melting process. In an electric boost melting process, once the electrical resistance of the raw material is sufficiently reduced, the electric boost can be initiated by generating an electrical potential between electrodes positioned in contact with the raw material, thereby establishing an electrical current through the raw material, which typically enters or is in a molten state.

[0033] Glass manufacturing apparatus 10 may also optionally include downstream glass manufacturing apparatus 30 positioned downstream of glass melting furnace 12 relative to the direction of flow of molten glass 28. In some examples, a portion of downstream glass manufacturing apparatus 30 may be incorporated as part of glass melting furnace 12. However, in some examples, a first connecting conduit 32, discussed below, or other portions of downstream glass manufacturing apparatus 30 may be incorporated as part of glass melting furnace 12.

[0034] The downstream glass-making apparatus 30 may include a first conditioning (i.e., processing) chamber, such as a fining vessel 34, located downstream of the melting vessel 14 and coupled to the melting vessel 14 by the first connecting conduit 32 described above. Molten glass 28 may be gravity-fed from the melting vessel 14 to the fining vessel 34 via an internal passageway of the first connecting conduit 32. The first connecting conduit 32 thus provides a flow path for the molten glass 28 from the melting vessel 14 to the fining vessel 34. However, other conditioning chambers may be positioned downstream of the melting vessel 14, for example, between the melting vessel 14 and the fining vessel 34. In some embodiments, a conditioning chamber may be employed between the melting vessel and the fining chamber. For example, the molten glass from the first melting vessel may be further heated in a second melting (conditioning) vessel or cooled in the second melting vessel to a temperature lower than the temperature of the molten glass in the first melting vessel before entering the fining chamber.

[0035] As previously mentioned, gas bubbles can be removed from the molten glass 28 by various techniques. For example, the raw material 24 may contain a polyvalent compound (i.e., a fining agent), such as tin oxide, that undergoes a chemical reduction reaction to release oxygen when heated. Other suitable fining agents include, but are not limited to, arsenic, antimony, iron, and cerium, although in some applications, the use of arsenic and antimony may be prohibited for environmental reasons. The fining vessel 34 is heated, for example, to a temperature higher than that of the melting vessel, thereby heating the fining agent. Oxygen produced by the temperature-induced chemical reduction of one or more fining agents contained in the molten glass diffuses into the gas bubbles created during the melting process. The enlarged and increasingly buoyant gas bubbles then rise to the free surface of the molten glass in the fining vessel and can then escape from the fining vessel.

[0036] The downstream glass manufacturing apparatus 30 may further include a mixing device 36, such as a stirring vessel or another conditioning chamber, for mixing the molten glass flowing downstream from the fining vessel 34. The mixing device 36 is used to provide a uniform glass melt composition, thereby reducing chemical or thermal inhomogeneities that may be present in the molten glass exiting the fining chamber. As shown, the fining vessel 34 may be coupled to the mixing device 36 via a second connecting conduit 38. In some embodiments, the molten glass 28 may be gravity-fed from the fining vessel 34 to the mixing device 36 via an internal passage in the second connecting conduit 38. The molten glass in the mixing device 36 may include a free surface, and a free volume may extend between the free surface and the top of the mixing device. Although the mixing device 36 is shown downstream of the fining vessel 34 relative to the direction of molten glass flow, the mixing device 36 may be positioned upstream of the fining vessel 34 in other embodiments. In some embodiments, downstream glass manufacturing equipment 30 may include multiple mixing devices, such as a mixing device upstream from fining layer 34 and a mixing device downstream from fining tank 34. These multiple mixing devices may be of the same design or may be of different designs. One or more of the tanks and / or conduits may include stationary mixing blades positioned therein to promote mixing and subsequent homogenization of the molten materials.

[0037] The downstream glass manufacturing apparatus 30 may further include another conditioning chamber, such as a delivery vessel 40 located downstream from the mixing apparatus 36. The delivery vessel 40 may be conditioned to deliver the molten glass 28 to a downstream forming device. For example, the delivery vessel 40 may function as an accumulator and / or a flow controller to regulate and provide a consistent flow of the molten glass 28 to the former 42 via an outlet conduit 44. The molten glass in the delivery vessel 40, in some embodiments, may include a free surface, with a free volume extending upward from the free surface to the top of the delivery chamber. As shown, the mixing apparatus 36 may be coupled to the delivery vessel 40 via a third connecting conduit 46. In some examples, the molten glass 28 may be gravity fed from the mixing apparatus 36 to the delivery vessel 40 via an internal passage of the third connecting conduit 46.

[0038] The downstream glass manufacturing system 30 may further include a forming apparatus 48 comprising the former 42 described above, including an inlet conduit 50. The outlet conduit 44 may be positioned to deliver the molten glass 28 from the delivery vessel 40 to the inlet conduit 50 of the forming apparatus 48.

[0039] Components of the downstream glass manufacturing equipment 30, including any one or more of the connecting conduits 32, 38, 46, the fining vessel 34, the mixing device 36, the delivery vessel 40, the outlet conduit 44, or the inlet conduit 50, may be formed from precious metals. Suitable precious metals include platinum group metals selected from the group consisting of platinum, iridium, rhodium, osmium, ruthenium, and palladium, or alloys thereof. For example, the downstream components of the glass manufacturing equipment may be formed from a platinum-rhodium alloy containing about 70% to about 90% by weight platinum and about 10% to about 30% by weight rhodium. However, other suitable metals for forming the downstream components of the glass manufacturing equipment include molybdenum, rhenium, tantalum, titanium, tungsten, and alloys thereof.

[0040] A former 42 in a fusion downdraw glass manufacturing apparatus may include a trough 52 positioned on the top surface of the former and a converging forming surface 54 (only one surface shown) that converges in the draw direction along a bottom edge (bottom) 56 of the former. Molten glass delivered to the former trough 52 via the delivery vessel 40, outlet conduit 44, and inlet conduit 50 overflows the walls of the trough 52 and descends along the converging forming surface 54 as separate streams of molten glass. The separate streams of molten glass join below and along the bottom 56 to produce a single ribbon of molten glass 58 that is elongated from the bottom 56 along the draw plane in a draw direction 60 by applying downward tension to the glass ribbon, such as by gravity rolls and / or pull roll assemblies (not shown), to control the dimensions of the glass ribbon as the molten glass cools and the viscosity of the material increases. Thus, the glass ribbon 58 undergoes a viscoelastic transition to an elastic state and acquires mechanical properties that provide the glass ribbon 58 with stable dimensional properties. The glass ribbon 58 includes a first outer edge 62a and a second outer edge 62b opposite the first outer edge 62a, the first outer edge and the second outer edge extending longitudinally along the glass ribbon 58. The glass ribbon 58 further includes a first thickened edge portion 64a and a second thickened edge portion 64b (hereinafter, first beads 64a and second beads 64b, respectively), where the beads 64a, 64b may extend inward from the respective first outer edge 62a and second outer edge 62b. The glass ribbon 58 includes a width W defined between the first outer edge 62a and the second outer edge 62b. The first beads 64a and the second beads 64b may have a thickness greater than the thickness of the glass ribbon along the longitudinal centerline of the glass ribbon. The glass ribbon extending between the first beads 64a and the second beads 64b may be referred to as a “quality” region 66 of the glass ribbon. The quality region 66 is the most commercially valuable portion of the ribbon, exhibiting a substantially uniform thickness and a pristine or substantially pristine surface, since the beads are typically removed and used as cullet or scrap.The glass ribbon 58 may, in some embodiments, be separated into individual glass sheets 68 by a glass separating apparatus 100, while in further embodiments, the glass ribbon 58 may be wound onto a spool and stored for further processing.

[0041] As shown in FIG. 2 , the glass separating apparatus 100 can include a carriage assembly 102 supported by multiple drive assemblies 104. Each drive assembly 104 of the multiple drive assemblies includes a screw shaft 106 coupled to a drive unit 108, and optionally a first bearing assembly 109 at one end of the screw shaft and a second bearing assembly 110 at the opposite end of the screw shaft. In addition, a nut assembly 112 can be coupled to each screw shaft 106, and each nut assembly 112 can be coupled to the carriage assembly 102, for example, at the opposite end of the carriage assembly. The glass separating apparatus 100 can include at least two drive assemblies 104, one drive assembly positioned and coupled to a first end of the carriage assembly 102 via a first nut assembly 112, and a second drive assembly positioned and coupled to a second end of the carriage assembly 102 via a second nut assembly 112. In some embodiments, the glass separating apparatus 100 can include at least four drive assemblies 104, two drive assemblies at one end of the carriage assembly 102 and two drive assemblies positioned and coupled to the opposite end of the carriage assembly 102.

[0042] The carriage assembly 102 may further include a scoring unit 120 for scoring the glass ribbon 58 and a scoring unit drive assembly 124 for moving the scoring unit 120 laterally along the carriage assembly 102. The scoring unit drive assembly 124 may include, for example, a belt coupled to a drive motor 128 and configured as an endless loop supported by rail members and rollers, with the scoring unit 120 also coupled to the belt. However, other methods of driving the scoring unit 120 may be employed. For example, the scoring unit 120 may be coupled to a linear actuator that moves the scoring unit along the length of the carriage. The scoring unit drive assembly 124 may move the scoring unit 120 laterally along the carriage assembly 102 in the draw direction 60 across the glass ribbon 58 for scoring the glass ribbon 58.

[0043] Each drive unit 108 associated with the carriage assembly 102 can include a drive motor 114 and a reduction gear assembly 116 coupling the drive motor 114 to the screw shaft 106. Each drive motor 114 can be a dedicated drive motor. That is, a drive motor can be dedicated to a single screw shaft 106 (driving the single screw shaft 106 and not the other screw shafts). Thus, for example, if there are two drive units 108, there will be two drive motors 114 coupled to two screw shafts 106 by two reduction gear assemblies 116. If there are four drive units 108, there will be four drive motors 114 coupled to four screw shafts 106 by four reduction gear assemblies 116. The reduction ratio of the reduction gear assemblies 116 can be less than 5:1, for example, in the range of about 4:1 to about 2:1, such as about 3.5:1. A reduction ratio of less than 5:1, provided by the reduction gear assembly 116 and / or the dedicated drive motor 114, can reduce the load borne by each drive assembly 104 during operation of the drive assembly. Thus, in such an embodiment, a smaller motor can be used than would be required if, for example, only a single drive motor were used for the pair of drive assemblies. Additionally, component life can be improved, and the vertical traverse speed of the carriage assembly 102, particularly during upward traverse, can be increased, thereby improving cycle time.

[0044] The drive unit 108 may be supported by a lower frame portion 118. The lower frame portion 118 may be any suitable rigid support capable of supporting the weight of the glass separating apparatus 100. For example, the lower frame portion 118 may be attached to a building beam, a concrete floor, or other suitable structural member of a building. In embodiments, the lower frame portion 118 may be a freestanding structure. The glass separating apparatus 100 may further include an upper frame portion 119 coupled to the drive assembly 104 at its upper end, for example, at a support bearing 110 attached to the upper frame portion 119. The upper frame portion 119 may provide rigidity to the drive assembly 104 and ensure uniform, consistent spacing between the drive assemblies (e.g., threaded shafts 106). The upper drive portion 119 may be connected to the lower frame portion 118.

[0045] Each nut assembly 112 may include a plurality of ball bearings housed in a housing, which engage raceways on the screw shaft 106. That is, each drive assembly 104 may include a ball screw device, and each screw shaft 106 is rotatable by a respective drive unit 108. As the screw shaft is rotated by a respective drive unit 108, the nut assembly 112 advances along the length of the screw shaft 106 in accordance with the direction of rotation of the screw shaft 106. Ball screw devices are known in the art, and their configuration will not be further described. Because the carriage assembly 102 is supported on the screw shaft 106 by the nut assembly 112, rotation of the screw shaft 106 by a respective drive unit 108 either raises or lowers the carriage assembly 102, depending on the direction of rotation of the screw shaft.

[0046] The drive unit 108 is used to laterally move the carriage assembly 102 during the scoring operation. As the glass ribbon 58 is drawn downward in the draw direction 60 at a draw speed, the carriage assembly 102 is moved downward parallel to the draw direction 60 at a downward lateral movement speed equal to the draw speed. During this downward lateral movement, the scoring unit 120 is moved laterally across the width of the glass ribbon, at which time a scoring tool disposed on the scoring unit scores the glass ribbon across at least a portion of the glass ribbon width. A robot (not shown) downstream of the carriage assembly 102 bends the glass ribbon at the scores, thereby separating the glass sheet from the glass ribbon. Once the scoring and separation operations are complete, the drive unit 108 reverses the rotation of the screw shaft 106 and traverses the carriage assembly 102 upward to the holding position until a sufficient length of the glass ribbon has passed the holding position to separate another glass sheet, at which point the drive unit again traverses the carriage assembly downward at the draw speed while the scoring unit scores the glass ribbon. Synchronizing the downward traverse speed of the carriage assembly 102, and thereby the scoring unit 120, with the draw speed allows scores to be made in the glass ribbon 58 perpendicular to the edge of the glass ribbon while it is moving.

[0047] The operation of the separation apparatus relies on adequate lubrication of the drive unit 108, particularly the screw shaft 106. Additionally, the separation of the glass sheet from the glass ribbon 58 generates glass particles that can adhere to parts of the drive unit, such as the screw shaft, which can be exacerbated by the lubricant. Accordingly, a bellows 200 may be provided around the screw shaft. A bellows 200 may be coupled to both parts of the screw shaft, one positioned around the lower portion of the screw shaft below the nut assembly 112 and one positioned around the upper portion of the screw shaft above the nut assembly 112. For example, the lower bellows 200 may be coupled at one end to the carriage assembly 102 and at the opposite end to the drive unit 108. A second bellows 200 may be positioned around the screw shaft 106 between the carriage assembly 102 and an upper frame portion 119, e.g., a second upper bearing assembly 110. The accordion-like pleated configuration of the bellows 200 allows the lower bellows 200 to compress and the upper bellows 200 to expand during downward lateral movement of the carriage assembly 102, and conversely, allows the upper bellows 200 to compress and the lower bellows 200 to expand during upward lateral movement of the carriage assembly 102.

[0048] The bellows 200 may be insufficient to prevent lubricant from the drive unit 108 from contaminating the glass ribbon and the glass sheet separated from the glass ribbon. For example, the area surrounding the separating device may be heated to control cooling of the glass ribbon, thereby applying stress to the glass ribbon, thereby vaporizing the lubricant. Furthermore, rather than a unitary bellows, such as a molded rubber bellows, in some embodiments, the bellows 200 may be formed from individual pieces connected together, such as individual pieces taped together. In some embodiments, the bellows 200 may be formed from a laminate material. In some embodiments, the laminate material may include an aluminum layer, a polymer layer such as polyvinyl chloride (PVC), and an organic paper layer such as kraft paper. The laminate material may include fiberglass. For example, the laminate material may include an aluminum fiberglass outer layer, a kraft paper middle layer, and a PVC inner layer, available as Alpha-Shield from Alpha Associates, Lakewood, NJ, USA. Vaporized lubricant can penetrate the seams between the individual pieces of the bellows and deposit, e.g., condense, on the glass ribbon 58. Lubricant contamination of the glass ribbon is difficult to remove and can permanently contaminate the glass ribbon.

[0049] A secondary shield in the form of a bellows cover 204 may be disposed around each bellows 200 to provide an additional barrier against lubricant leaking from the bellows 200. The bellows cover 204 may be a fabric (e.g., a woven, knit, or felt fabric) configured into a tubular shape, with the bellows 200 and the screw shaft 106 positioned therein disposed within the tube. The bellows cover fabric may include silica. For example, in embodiments, the fabric may include glass fiber (e.g., a fiberglass fabric). In embodiments, the fabric may include Heptasil™ 610, available from Heptagon Industries of Singapore. The bellows cover 204 may be formed into a tube, for example, by joining opposing ends of the fabric along seam 205 and fastening them together by, for example, taping or other means such as hook-and-loop fastening (e.g., Velcro®) to form a tube that extends around the bellows 200. The use of hook-and-loop fasteners facilitates quick installation or removal of the bellows cover during operation of the glass manufacturing equipment, for example, for replacement or cleaning. The bellows cover 204 is heat-resistant and flexible, allowing it to compress and expand in unison with the bellows 200 as the bellows alternately compress and expand during the reciprocating motion of the carriage assembly 102. Additionally, the bellows cover 204 reduces the temperature of the environment within the bellows, thereby reducing evaporation of lubricant from the screw shaft and subsequent contamination of the glass ribbon. The bellows cover 204 has been found to reduce the temperature within the bellows (e.g., between the bellows 200 and the screw shaft 106) by as much as 20%.

[0050] One end of the bellows cover 204 may be coupled to a corresponding frame portion, such as the upper frame portion 119 or the lower frame portion 118, for example, to the bearing assemblies 109, 110, or another support unit, by a clamping device 206. In FIG. 3, the bellows cover 204 is shown disposed around the screw shaft 106 and the upper portion of the bellows 200 and coupled to the upper frame portion 119 between the carriage assembly 102 and the upper frame portion. Similarly, the opposite end of the bellows cover 204 may be coupled to the carriage assembly 102, for example, by a second clamping device 102. The clamping device 206 may include a shroud 208 and a plate 210. One or more restraining clamps 212 attached to the shroud 208 may engage with formed wires 214 disposed on one or both ends of the bellows cover 204. That is, the bellows cover 204 may include a shaped wire 214 attached to the end of the bellows cover to maintain the shape of the bellows cover at the end and to provide a rigid member for clamping the bellows cover thereon. For example, the shaped wire may be inserted into a loop formed in the end of the bellows cover. In the embodiment shown in FIG. 3, the restraining clamps 212 engage the bellows cover 204 such that the shaped wire is captured by the restraining clamps, thereby preventing removal of the bellows cover until the clamps are relaxed or removed. As shown in FIG. 4, the shaped wire 214 may be inserted into a loop in the end of the bellows cover. In the embodiment shown in FIG. 3, each restraining clamp 212 may include a bracket 216 attached to the shroud 208, one or more clamping screws 218, and a clamping bar 220. As shown, the bracket 216 may be an L-shaped bracket with one or more clamping screws 218 engaging the bracket through threaded openings in the bracket, and the clamping screws 218 further engaging a clamping bar.5 , in a further embodiment, the clamping screw 218 may be replaced with a pin 222 that extends through and slidably engages an opening in the bracket 216, with the pin 222 attached to the clamping bar 220 at its distal end. The opposing proximal end of the pin is attached to a stop member 224. Thus, the clamping bar 220 and stop member 224 are movable relative to the bracket 216 along the longitudinal axis of the pin 222 as the pin 222 slides within the opening in the bracket 216. Additionally, the pin 222 extends through a spring 226, e.g., a helical compression spring, which is captured on the pin 222 between the bracket 216 and the clamping bar 220. The springs 226 exert a biasing spring force on the clamping bar 220 such that when the bellows cover 204 is positioned between the clamping bar 220 and the shroud 208, e.g., on the shroud 208 or a clamping block 228 coupled to a portion of the shroud 208, the biasing spring force presses the clamping bar 220 against the bellows cover (e.g., a clamp block) and holds the bellows cover in place against the shroud 208. The formed wire 214 prevents the bellows cover from being pulled from the restraining clamp until the springs 226 are compressed, releasing the biasing spring force from the bellows cover and allowing the bellows cover 204 to be removed. In embodiments, the restraining clamp 212 may include multiple pins and springs. For example, in the embodiment shown in FIG. 5, the restraining clamp 212 includes two sets of pins 222 and springs 226. The shroud 208 may be coupled to a plate 210, which may be coupled to a corresponding frame portion, such as the bearing assemblies 109, 110, or other mounting structure coupled to a corresponding frame portion.

[0051] In an embodiment, the plate 210 may include an exhaust port 230 including a fitting 232 therein configured to receive a tube line 234 in fluid communication with a vacuum source (not shown). The exhaust port 230 provides fluid communication between the tube line 234 and an interior space 236 between the bellows cover 204 and the bellows 200, as indicated by arrow 238, such that air within the interior space 236 can be exhausted along with any airborne particles. For example, the bellows cover 204 itself may emit small fibrous particles. As the carriage assembly 102 transversely moves the screw shaft in a direction that compresses the bellows 200 (and the bellows cover 204), particles emitted by the bellows cover may be exhausted from the interior space 236 between the bellows cover and the bellows. Such exhausted particles may then contaminate the glass ribbon 58. Removing particles from the interior space 236 via vacuum reduces the chance of exhausting such particles into the open atmosphere of the manufacturing facility.

[0052] In an embodiment, both ends of the bellows cover 204 can be coupled to a respective upper or lower frame portion by clamping devices 206, and each clamping device 206 can be positioned in fluid communication with a vacuum source by tubing lines 234 so that particles in an interior space 236 between the bellows cover 204 and the bellows 200 can be vacuumed from the interior space 236. The applied vacuum can also be effective to remove lubricant vapors from the interior space 236.

[0053] The clamping device 206 may couple the bellows 200 and the bellows cover 204 to the respective frame portion (e.g., the lower frame portion 118 or the upper frame portion 119) and / or the carriage assembly 102. For example, each set of bellows 200 and bellows cover 204 extending between the respective frame portion (e.g., the lower frame portion 118 or the upper frame portion 119) and the carriage assembly 102 and surrounding a portion of the screw shaft 106 may be coupled to the respective frame portion and the carriage assembly 102 by the clamping device 206 so that a vacuum can be applied to the interior space between the bellows 200 and the bellows cover 204 and to the interior space between the bellows 200 and the screw shaft 106 at both ends of the bellows 200 and the bellows cover 204. Thus, for example, each screw shaft 106 may have two sets of bellows 200 and bellows covers 204: a first set of bellows 200 and bellows covers 204 positioned between one end of the carriage assembly 102 and a frame portion (e.g., the lower frame portion 118 or the upper frame portion 119), and a second set of bellows 200 and bellows covers 204 positioned between one end of the carriage assembly 102 and the other end of the upper or lower frame portion. A second screw shaft coupled to the opposite end of the carriage assembly may include a similar set of bellows and bellows covers. In some embodiments, the glass separating apparatus 100 may include multiple screw shafts and associated nut assemblies positioned at each end of the carriage assembly 102. For example, the glass separating apparatus may include two screw shafts coupled to a first end of the carriage assembly 102 and two screw shafts coupled to a second end of the carriage assembly 102. Each screw shaft may be protected above and below the carriage assembly by bellows, i.e., the upper portion of each screw shaft above the carriage assembly may be provided with bellows, and each screw shaft below the carriage assembly may be provided with bellows.In some cases, the bellows cover associated with the upper bellows may be sized to accommodate both upper bellows within a single upper bellows cover, and similarly, the bellows cover associated with the lower bellows may be sized to accommodate both lower bellows with a single lower bellows cover.

[0054] 6 and 7 , in some embodiments, the bellows cover 204 can be coupled to a vacuum ring 300 disposed between the bellows cover 204 and a respective upper or lower frame portion. The vacuum ring 300 can include a plurality of exhaust ports in fluid communication with tubing lines in fluid communication with one or more vacuum sources. In embodiments, the vacuum ring can include a first outer ring wall 302 and a second inner ring wall 304 positioned inside the outer ring wall 302, such as concentric with the outer ring wall 302. The inner ring wall 304 is spaced apart from the outer ring wall 302 by a first gap 306 and spaced apart from the screw shaft 106 by a second gap 308. Bellows 200 can be coupled to inner ring wall 304, and bellows cover 204 can be coupled to outer ring wall 302, such that a first gap 306 between bellows 200 and threaded shaft 106 is separated from a second gap 308 between bellows 200 and bellows cover 204. Vacuum ring 300 can include at least one first exhaust port 310 in fluid communication with a first vacuum source (not shown) configured to evacuate lubricant vapors from the space between screw shaft 106 and bellows 200, as indicated by arrow 314, and associated tubing line 312, and at least one second exhaust port 316 in fluid communication with either the first vacuum source or a second vacuum source configured to remove particles between bellows 200 and bellows cover 204, as indicated by arrow 320, and associated tubing line 318. The vacuum ring 300 may couple the bellows 200 and bellows cover 204 to a respective frame portion (eg, the lower frame portion 118 or the upper frame portion 119 ) and / or the carriage assembly 102 .For example, each set of bellows 200 and bellows cover 204 extending between a respective frame portion (e.g., lower frame portion 118 or upper frame portion 119) and carriage assembly 102 and surrounding a portion of screw shaft 106 may be coupled to the respective frame portion and carriage assembly 102 by a vacuum ring 300 so that a vacuum can be applied to first gap 306 and second gap 308 at both ends of the gaps (i.e., both ends of bellows 200 and bellows cover 204).

[0055] It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments of the present disclosure without departing from the spirit or scope of the disclosure. Thus, it is intended that the present disclosure cover such modifications and variations insofar as they come within the scope of the appended claims and their equivalents.

Claims

1. 1. A glass manufacturing apparatus comprising: a former configured to form a glass ribbon; a separating device configured to separate the glass ribbon, the separating device comprising: a frame assembly comprising an upper frame portion and a lower frame portion; a carriage assembly; a drive assembly coupled to the carriage assembly and including a screw shaft extending between the upper frame portion and the lower frame portion; a bellows extending over the screw shaft; a bellows cover extending over the bellows.

2. The glass manufacturing apparatus of claim 1 , wherein the bellows comprises aluminum.

3. The glass manufacturing apparatus of claim 1 or 2, wherein the bellows comprises a polymer.

4. The glass manufacturing apparatus of claim 1 , wherein the bellows cover comprises fabric.

5. The glass manufacturing apparatus of claim 4 , wherein the fabric comprises glass fibers.

6. 2. The glass manufacturing apparatus of claim 1, further comprising a first clamp assembly coupling a first end of the bellows cover to the carriage assembly, the first clamp assembly comprising a first vacuum line extending between a vacuum source and the first clamp assembly such that the vacuum source is in fluid communication with an interior space between the bellows and the bellows cover.

7. 7. The glass manufacturing apparatus of claim 6, further comprising a second clamp assembly coupling a second end of the bellows cover to the lower frame portion, the second clamp assembly comprising a second vacuum line extending between the vacuum source and the second clamp assembly such that the vacuum source is in fluid communication with the interior space between the bellows and the bellows cover.

8. 10. The glass manufacturing apparatus of claim 1, comprising a vacuum ring comprising: a first ring wall; a second ring wall inside the first ring wall and spaced a first gap from the first ring wall and a second gap from the screw shaft, wherein the bellows cover is coupled to the first ring wall and the bellows is coupled to the second ring wall; a first vacuum line coupled to the vacuum ring and in fluid communication with the first gap; and a second vacuum line coupled to the vacuum ring and in fluid communication with the second gap, wherein the first gap is not in fluid communication with the second gap.

9. 10. The glass manufacturing apparatus of claim 8, further comprising a second vacuum ring coupling a second end of the bellows cover to the lower frame portion.

10. The glass manufacturing apparatus of claim 1 , wherein the drive assembly comprises a ball screw.

11. 1. A glass manufacturing apparatus comprising: a former configured to form a glass ribbon; a separating device configured to separate the glass ribbon, the separating device comprising: a frame assembly comprising an upper frame portion and a lower frame portion; a carriage assembly; a drive assembly comprising: a screw shaft extending between the upper frame portion and the lower frame portion, the screw shaft coupled to a drive motor configured to rotate the screw shaft; and a nut assembly coupled to the carriage assembly and engaged with the screw shaft such that rotation of the screw shaft by the drive motor moves the carriage assembly along the screw shaft between the upper frame portion and the lower frame portion; a bellows extending over the screw shaft between the lower frame portion and the carriage assembly; a bellows cover extending over the bellows.

12. The glass manufacturing apparatus of claim 11 , wherein the bellows cover comprises a fiberglass fabric.

13. 12. The glass manufacturing apparatus of claim 11, further comprising a first clamp assembly coupling a first end of the bellows cover to the carriage assembly, the first clamp assembly comprising a first vacuum line extending between a vacuum source and the first clamp assembly such that the vacuum source is in fluid communication with an interior space between the bellows and the bellows cover.

14. 14. The glass manufacturing apparatus of claim 13, further comprising a second clamp assembly coupling a second end of the bellows cover to the lower frame portion, the second clamp assembly comprising a second vacuum line extending between the vacuum source and the second clamp assembly such that the vacuum source is in fluid communication with the interior space between the bellows and the bellows cover.

15. 12. The glass manufacturing apparatus of claim 11, comprising a vacuum ring comprising: a first ring wall; a second ring wall inside the first ring wall and spaced a first gap from the first ring wall and a second gap from the screw shaft, wherein the bellows cover is coupled to the first ring wall and the bellows is coupled to the second ring wall; a first vacuum line coupled to the vacuum ring and in fluid communication with the first gap; and a second vacuum line coupled to the vacuum ring and in fluid communication with the second gap, wherein the first gap is not in fluid communication with the second gap.

Images