Vacuum insulated glass (vig) units and methods of making the same

Abstract

Certain example embodiments of the present invention relate to vacuum insulated glass (VIG) units and / or methods of making the same. A sealing tube or sealing material is disposed within the VIG unit, thereby potentially eliminating the need for a protective superstate and enabling greater freedom in handling, frame design, hybrid VIG construction, lamination, etc. In at least certain example embodiments, the sealing tube can be repositioned to an interior region within a recessed pocket of the base. The VIG unit is free of protruding pump-out tubes, etc.

Description

[0001] This application is a continuation-in-part of patent application number 202080007536.X, entitled “Internal tube for vacuum insulated glass (VIG) unit evacuation and hermetic sealing, VIG unit comprising the internal tube, and associated methods,” filed on January 6, 2020. TECHNICAL FIELD

[0002] Certain example embodiments of this application relate to vacuum insulated glass (VIG) units and / or methods of making the same. More particularly, certain example embodiments of this application relate to an internal pump-out tube for VIG unit evacuation and hermetic sealing, a VIG unit subassembly comprising the internal pump-out tube, a VIG unit made using the internal pump-out tube, and / or associated methods.

[0003] BACKGROUND AND SUMMARY

[0004] Vacuum insulated glass (VIG) units generally include at least two spaced apart glass substrates that enclose an evacuated or low pressure space / cavity therebetween. The substrates are interconnected by a peripheral edge seal, and typically include spacers between the glass substrates to maintain the spacing between the glass substrates and to avoid collapse of the glass substrates due to the low pressure environment existing between the substrates. Some example VIG configurations are disclosed, for example, in U.S. Patents 5,657,607; 5,664,395; 5,902,652; 6,506,472; and 6,383,580, the disclosures of which are hereby incorporated by reference in their entireties.

[0005] Figures 1-2 A typical VIG unit 1 and elements forming the VIG unit 1 are shown. For example, the VIG unit 1 can include two spaced apart, substantially parallel glass substrates 2, 3 that enclose an evacuated, low pressure space / cavity 6 therebetween. The glass sheets or substrates 2, 3 are interconnected by a peripheral edge seal 4, which can be made of, for example, a fused solder glass. An array of support posts / spacers 5 can be included between the glass substrates 2, 3 to maintain the spacing of the substrates 2, 3 of the VIG unit 1 according to the low pressure space / gap 6 existing between the substrates 2, 3.

[0006] The pump-out tube 8 can be hermetically sealed to the hole / hole 10 by, for example, a solder glass 9 that leads from the interior surface of one of the glass substrates 2 to the bottom of an optional recess 11 in the exterior surface of the glass substrate 2, or optionally to the exterior surface of the glass substrate 2. A vacuum pump is attached to the pump-out tube 8 to evacuate the interior cavity 6 to a low pressure, for example, using a sequential gas evacuation operation. After the cavity 6 is evacuated, a portion of the tube 8 (e.g., the tip) is melted to seal the vacuum in the low pressure cavity / space 6. The optional recess 11 can hold the sealed pump-out tube 8. Optionally, a chemical getter 12 can be included within a recess 13 disposed in the interior surface of one of the glass substrates (e.g., glass substrate 2). The chemical getter 12 can be used to absorb or bind certain residual impurities that can remain after the cavity 6 is evacuated and sealed.

[0007] VIG units with a fused solder glass perimeter edge seal 4 are typically manufactured by depositing a frit in solution (e.g., a glass paste) around the perimeter of the substrate 2 (or on the substrate 3). The glass paste ultimately forms the glass solder edge seal 4. The other substrate (e.g., 3) is placed down on the substrate 2 so as to sandwich the spacers / struts 5 and the frit solution between the two substrates 2, 3. The entire assembly including the glass substrates 2, 3, the spacers / struts 5, and the sealing material (e.g., glass frit in solution or paste) is then heated to a temperature of at least about 500°C at which time the frit melts, wets the surfaces of the glass substrates 2, 3, and ultimately forms a hermetic perimeter / edge seal 4.

[0008] After the edge seal 4 is formed between the substrates, a vacuum is drawn via the pump-out tube 8 to form a low pressure space / cavity 6 between the substrates 2, 3. The pressure in the space 6 can be produced to a level below atmospheric pressure (e.g., below about 10 -2 Torr) by the evacuation process. In order to maintain the low pressure in the space / cavity 6, the substrates 2, 3 are hermetically sealed. Small, high strength spacers / struts 5 are provided between the substrates to resist atmospheric pressure and maintain the separation of the substrates in generally parallel. As noted above, once the space 6 between the substrates 2, 3 is evacuated, the pump-out tube 8 can be sealed, for example, by melting its tip using a laser or the like.

[0009] A typical method for installing the pump-out tube 8 in the hole or hole 10 includes inserting a preformed glass pump-out tube 8 into the hole / hole 10 that has been previously formed (e.g., by drilling) in one of the glass substrates 2. After the pump-out tube 8 has been seated in the hole / hole 10, an adhesive glass frit paste is typically applied to the pump-out tube 8 in the area near the opening of the hole 10 proximate the exterior surface of the glass substrate 2. As noted above, the pump-out tube can be sealed after the VIG unit cavity is evacuated or purged.

[0010] After the chamber is evacuated to a pressure less than atmospheric pressure, the sealing of the pump-out tube, which is used to evacuate or purge the cavity to melt the opening and thus seal the cavity of the VIG unit, can be achieved by heating the end of the pump-out tube. For example, but not by way of limitation, such heating and melting can be achieved by laser irradiation of the end of the pump-out tube.

[0011] It can sometimes be the case that the pump-out tube can not be properly seated in the hole formed in the glass substrate. Thus, the pump-out tube can be leaning or tilted, thus not substantially perpendicular to the surface of the glass substrate in which the hole is formed. Thus, in the case where the pump-out tube is not properly seated and is at an undesired angle with respect to the surface of the glass substrate, it can become difficult to properly seal the pump-out tube as the laser can not uniformly melt the end of the pump-out tube due to, for example, differences in the distance between various portions of the angled top of the pump-out tube and the laser source. Inconsistent melting of the top of the pump-out tube can result in an incomplete seal and thus air leakage, which can occur quickly or more slowly over time depending on the quality of the seal. Furthermore, based on the degree of tilt or lean of the tube, the laser can hit the tube wall instead of the top. If the laser hits the tube wall, the laser can potentially bypass the tube and hit the frit, which can damage the frit or cause undesired outgassing into the cavity.

[0012] It can seem desirable to provide a way of seating the pump-out tube in the hole to reduce the amount of lean of the tube to within an acceptable range. In this regard, improvements to the evacuation and / or lean process have been attempted. See, for example, U.S. Patents 9,371,683 and 8,833,105 and U.S. Pub. 2013 / 0306222, the entire contents of each of these patents hereby incorporated by reference herein. Such techniques are advantageous compared to conventional methods. But the inventors of the present patent application have recognized that further improvements are still possible.

[0013] For example, even when the pump-out tubes are properly oriented with respect to the substrate, they still protrude outward from the outermost surface of the VIG unit. If the sealed tubes are jostled, knocked loose, or broken in whole or in part, the VIG unit can lose vacuum faster than otherwise desired. A top cap is sometimes provided over the protruding sealed tubes to help prevent impacts that can cause breakage, etc., but such top caps have limited effect against heavy mechanical forces and add an additional processing step and material to the VIG unit manufacturing process.

[0014] This conventional arrangement is Figure 3More fully illustrating, the figure is a schematic cross-sectional view of a VIG unit with a sealed pump-out tube 8 that protrudes outward from the VIG unit and is protected using a top cap 15. When the VIG unit is evacuated and then sealed, a pump-out port is used to allow an evacuation path. Conventionally, this port is typically sealed by inserting a tube 8 with frit 9 applied thereon into a hole drilled in the glass 2, firing the frit 9 around the hole, sealing the frit 9 in place, and sealing the tube 8 by melting it with a laser, resistive filament, or similar focused energy source, thereby hermetically sealing the VIG unit. The protective top cap 15 is attached to the glass surface via adhesive tape 16 or other means to help protect the delicate tube 8 protruding from the glass surface.

[0015] Accordingly, it will be appreciated that it is desirable to completely eliminate the need for a pump-out tube that protrudes outward from the outermost surface of a VIG unit and / or its top cap.

[0016] One aspect of certain example embodiments involves the use of a pump-out tube that is internal to the VIG unit. In certain example embodiments, there is no need for a pump-out tube that protrudes outward from the outermost surface of the VIG unit. Such an arrangement simplifies the manufacturing process in certain example instances, for example, by eliminating the need to provide and seal a separate top cap, making shipping, handling, transportation, and / or other processing operations easier because of the less care needed due to the elimination of a critical but very fragile element of the VIG unit. Frame design, lamination, IG construction, and the like can also be simplified.

[0017] Another aspect of certain example embodiments involves the sealing of the internal pump-out tube such that the sealed tube does not protrude beyond the outermost surface of the VIG unit (e.g., is flush with it or below it). Such an arrangement is advantageous in certain example instances because it can reduce and sometimes eliminate the need for a separate protruding protective top cap that is placed above the tube. In turn, the removal of the protective top cap can be advantageous from an aesthetic standpoint. Furthermore, the removal of the protective top cap can be advantageous in terms of reducing the likelihood of damaging the VIG unit and making shipping, handling, transportation, and / or other processing operations easier. With respect to the former, as alluded to above, an impact top cap can translate forces to the sealed tube, which can cause it to move and / or break, thereby compromising the quality of the vacuum of the VIG. With respect to the latter, because the top cap is missing, it can be avoided that special shipping and / or packaging materials that accommodate such top caps must be used.

[0018] In certain example embodiments, a method of manufacturing a vacuum insulated glass (VIG) unit is provided. A first glass substrate and a second glass substrate are provided, with the second substrate including a hole formed therein, with the hole formed to have a first portion and a second portion, with the first portion closer to an outer surface of the second substrate than the second portion, with the first portion having a first width across the second substrate and the second portion having a second width across the second substrate, and with the first width narrower than the second width, the first portion and the second portion together forming a through-hole through the second substrate. A pump-out tube is placed in the hole. The first substrate and the second substrate are sealed together with an edge seal disposed around a peripheral edge of the first substrate and / or the second substrate, with a cavity defined by the first substrate and the second substrate, and a plurality of spacers disposed in the cavity between the first substrate and the second substrate and helping to maintain the first substrate and the second substrate in a spaced apart relationship substantially parallel to each other. The cavity is evacuated to a pressure less than atmospheric pressure. The pump-out tube is heated to collapse a portion of the tube adjacent the first substrate inward on itself to cover the second width and hermetically seal the VIG unit and form a sealed tube, with the sealed tube entirely inside the VIG unit.

[0019] In certain example embodiments, a method of manufacturing a vacuum insulated glass (VIG) unit sub-assembly is provided. A second glass substrate is provided, with the second substrate including a hole formed therein, with the hole formed to have a first portion and a second portion, with the first portion closer to an outer surface of the second substrate than the second portion, with the first portion having a first width across the second substrate and the second portion having a second width across the second substrate, with the first width narrower than the second width, and with the first portion and the second portion together forming a through-hole through the second substrate. The second substrate is transferred to another party to: place a pump-out tube in the hole; seal a first glass substrate with the second substrate together with an edge seal disposed around a peripheral edge of the first substrate and / or the second substrate, with a cavity defined by the first substrate and the second substrate, a plurality of spacers disposed in the cavity between the first substrate and the second substrate, and helping to maintain the first substrate and the second substrate in a spaced apart relationship substantially parallel to each other. Evacuate the cavity to a pressure less than atmospheric pressure; and laser heat the pump-out tube to collapse a portion of the tube adjacent the first substrate inward on itself to cover the second width and hermetically seal the VIG unit and form a sealed tube, the sealed tube entirely inside the VIG unit.

[0020] In certain example embodiments, a vacuum insulated glass (VIG) unit is provided, including a first glass substrate and a second glass substrate maintained in spaced apart relationship substantially parallel to each other via a hermetic edge seal and a plurality of spacers disposed in a cavity defined between the first and second glass substrates, the cavity evacuated to a pressure less than atmospheric pressure using a pump-out port hermetically sealed with a laser sealed tube laser, the laser sealed tube including a sealed portion thereof manufactured adjacent the cavity, the laser sealed tube located inside the VIG unit and not protruding therefrom.

[0021] In certain example embodiments, a method of manufacturing a vacuum insulated glass (VIG) unit is provided. The method includes having a first glass substrate and a second glass substrate, the second substrate including a through hole formed therein. A cover is placed over the hole on the second glass substrate. The first and second substrates are sealed together with an edge seal disposed around a peripheral edge of the first and / or second substrates, a cavity is defined by the first and second substrates, a plurality of spacers are disposed in the cavity between the first and second substrates and facilitate maintaining the first and second substrates in spaced apart relationship substantially parallel to each other, the cover is disposed between the first and second substrates. The cavity is evacuated to a pressure less than atmospheric pressure. After the evacuation, the cover is connected to an interior surface of the second substrate and hermetically seals the VIG unit, the cover being entirely inside the VIG unit.

[0022] In certain example embodiments, a vacuum insulated glass (VIG) unit is provided, including a first glass substrate and a second glass substrate maintained in spaced apart relationship substantially parallel to each other via a hermetic edge seal and a plurality of spacers disposed in a cavity defined between the first and second glass substrates, the cavity evacuated to a pressure less than atmospheric pressure using a pump-out port hermetically sealed with a cover, the cover disposed in the cavity without protruding from the VIG unit.

[0023] The features, aspects, advantages, and example embodiments described herein can be combined to realize yet further embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0024] These and other features and advantages can be better understood with reference to the following exemplary illustrative embodiments described in connection with the drawings, in which:

[0025] Figure 1 is a cross-sectional schematic view of a conventional vacuum insulated glass (VIG) unit;

[0026] Figure 2 is a top plan view of a conventional VIG unit;

[0027] Figure 3 is a cross-sectional schematic view of a VIG unit having a sealed pump-out tube that protrudes outward from the VIG unit and is protected using a top cap;

[0028] Figure 4 is a cross-sectional schematic view showing how a first example internal pump-out tube can be sealed according to certain example embodiments;

[0029] Figure 5 is a cross-sectional schematic view showing a first example internal pump-out tube sealed according to certain example embodiments; Figure 4

[0030] Figure 6 is a cross-sectional schematic view showing how a second example internal pump-out tube can be sealed according to certain example embodiments;

[0031] Figure 7 is a cross-sectional schematic view showing a second example internal pump-out tube sealed according to certain example embodiments; Figure 6

[0032] Figure 8 is a flowchart showing an example method for manufacturing a VIG unit in conjunction with an internal pump-out tube according to certain example embodiments;

[0033] Figure 9 is a cross-sectional schematic view showing another method of sealing a pump-out port according to certain example embodiments; and

[0034] Figure 10 is a flowchart showing another example method for manufacturing a VIG unit in conjunction with an internal seal according to certain example embodiments. DETAILED DESCRIPTION

[0035] ​​Certain example embodiments relate to improved techniques for evacuating vacuum insulated glass (VIG) units. More particularly, certain example embodiments of the present invention relate to an internal pump-out tube for VIG unit evacuation and hermetic sealing, a VIG unit subassembly including the internal pump-out tube, a VIG unit manufactured using the internal pump-out tube, and / or associated methods. Typically, the interior space of a VIG unit is evacuated through a surface-mounted tube or other structure that facilitates sealing once the interior space reaches a sufficiently low pressure. Even when sealed, the tube or other structure protrudes from the surface and is typically protected with a protective cap, but often requires special handling. Certain example embodiments improve upon this approach by repositioning the sealing tube inside the VIG unit, thereby potentially eliminating the need for a protective cap and enabling greater freedom in handling, frame design, hybrid VIG construction, lamination, etc. In essence, at least in certain example embodiments, the sealing tube is repositioned to an interior surface within a recessed pocket.

[0036] In certain example embodiments, the sealed internal tube is flush with or recessed relative to the exterior surface of the glass of the VIG. As a result, there is no need to apply a protective cap thereover. This in turn can result in easier processing, especially for secondary processes such as lamination, hybrid VIG manufacturing, etc. Additionally, eliminating an external tube that protrudes outward from the base can enable improvements in shipping methods, e.g., because additional packaging dunnage need not be provided to properly space apart VIG units to account for the extra protrusion. In certain example embodiments, standard or more standard packaging, etc. can be used.

[0037] There are a variety of internal tube designs that can be used in conjunction with certain example embodiments. In this regard, Figure 4 is a cross-sectional schematic that illustrates how a first example internal pump-out tube 8a can be sealed in accordance with certain example embodiments, and Figure 5 is a cross-sectional schematic that illustrates a first example internal pump-out tube 8a sealed in accordance with certain example embodiments. Figure 4 is a cross-sectional schematic that illustrates a first example internal pump-out tube 8a sealed in accordance with certain example embodiments.

[0038] The tube 8a is recessed in the interior space of the VIG unit 10 in certain example embodiments. Figure 4The tube 8a is located inside the VIG unit sub-assembly and is substantially situated in a recess drilled in the substrate 3. The tube 8a can be held in place using glass frit 9, which can be fired according to conventional methods. However, the tube 8a itself does not protrude beyond the outer surface of the substrate 3. There is almost no space between the substrates 2 and 3 because the cavity defined therebetween is quite narrow. However, the recess in which the tube 8a is located is advantageous because it allows more tube material to be exposed and used to form a seal, as will be understood from the description below. The port in which the tube 8a will be located can be formed by drilling a through-hole of a first diameter or main distance, and the recess can be formed by drilling a recess in the substrate adjacent to the through-hole. This recess is not a through-hole, otherwise it would only serve as a larger (or supplementary) pump outlet port. The through-holes and recesses used to form the recess can be formed to be aligned with each other, for example, such that the approximate centers of each through-hole and recess are substantially aligned (e.g., from a plan view and / or a cross-sectional perspective view, the latter can be determined according to...). Figure 4 (Understanding). In some exemplary embodiments, the through-holes and recesses used to form the pits may be substantially circular in a plan view, but other configurations are possible in different exemplary embodiments.

[0039] Figure 4 The VIG unit subassembly shown uses a vacuum pump 19 to evacuate through tube 8a, which is open to the internal air space or cavity. The vacuum cup is... Figure 4 The example is shown, but it is not required for all implementations (e.g., in implementations where the entire subassembly is processed under vacuum conditions). When a sufficiently low pressure is reached, a laser 21 is used to seal tube 8a. The laser 21 can be directed through another glass substrate 2 to heat the tube 8a at one point adjacent to the cavity and promote the relaxation of the molten tube material until it eventually covers the hole. This will cause the sidewalls of tube 8a to begin to relax inwards. As the bridging begins to form, the laser 21 can track the degree of relaxation, thereby hermetically sealing tube 8a. The sealed tube 8a′ is in... Figure 5 As shown in the image.

[0040] The glass substrate 2 is preferably sufficiently transparent to the wavelength of the laser 21 to avoid absorbing a large amount of energy before it reaches the tube 8a. In contrast, the tube 8a is preferably sufficiently opaque to that wavelength to absorb energy and form a seal. In this sense, the tube 8a may be preferentially heated (e.g., compared to the substrate 2 and / or the substrate 3).

[0041] Additionally, in certain example embodiments, the heating can be preferential heating, which includes a first heating stage or core heating stage that substantially melts the tube (or sealing sidewall), followed by a second stage that allows the tube (or sealing sidewall) to relax together and form a bridge. One or both of these stages can preferentially heat the tube (or sealing sidewall) relative to the rest of the VIG unit subassembly, including, for example, the overlying substrate. In different example embodiments, laser heating can be used for either stage or both stages. While laser heating is mentioned herein, it should be understood that infrared (IR) heating can be used in conjunction with any of the heating procedures described herein.

[0042] Figure 6 is a cross-sectional schematic showing how a second example internal pump-out tube can be sealed according to certain example embodiments, and Figure 7 is a cross-sectional schematic showing a second example internal pump-out tube sealed according to certain example embodiments. Figure 6 is a cross-sectional schematic showing a second example internal pump-out tube sealed according to certain example embodiments. Figures 6-7 is similar to Figures 4-5 .

[0043] However, Figures 6-7 shows a pump-out tube 8b inserted into a hole that includes one or more steps 23. The presence of one or more steps 23 can be advantageous in helping to reduce the likelihood of the tube 8b falling through the glass substrate 3, for example during machining operations, including during evacuation. The steps 23 also help to reduce the likelihood of the tube sliding into a position where it can protrude from the outer surface of the substrate 3, for example as shown in the sealed tube 8b’ in Figure 7 . Frit can also be applied over the stepped portions. The steps 23 can be formed via any suitable technique such as, for example, drilling. The alignment, configuration options, etc. described above with respect to through-holes and recesses can also be applied with respect to the stepped portions.

[0044] In certain example embodiments, the machined pocket can be expanded to allow getter to be inserted around the sealed tube. The expanded area 25 is shown in Figure 6 , but this approach can be used in conjunction with other example embodiments, including Figure 4 example embodiments.

[0045] In certain example embodiments, the tube and sealing frit can be installed with a pre- temper, for use in constructing a tempered VIG unit. The sealing frit can be fired during the tempering process, which can allow for higher melting point frit to be used for obtaining a hermetic seal.

[0046] In certain example embodiments, the pump-out tube can be integral with the base. For example, the profile / cross-section can be formed by forming a through-hole and a channel or trench around the through-hole. The glass left between the through-hole and the channel forms one or more sidewalls of the through-hole and / or the sealing arms of the VIG unit itself. These features can be formed in any suitable manner such as, for example, by drilling into the base. In this sense, the internally-integrated pump-out tube is at least partially defined by the through-hole and the trench / channel formed around the through-hole. Ultimately, the sealing arms can be melted to collapse over the through-hole and form a “plug-free” bridge of the hermetically sealed VIG unit, which is similar to the case where a separate tube is provided.

[0047] When viewed in cross-section, the recess can be generally U-shaped, semi-circular, trapezoidal, etc. Successive drilling operations can also be performed, for example, in a more stepped manner to approximate these and / or other shapes.

[0048] When viewed in plan, the through-hole and / or recess can use generally circular, oval, square, rectangular, and / or other features in different example embodiments. For example, generally square, oval, and / or other configurations when viewed from plan can be used in different example embodiments. It should also be understood that different shaped features can be used in conjunction with a single embodiment. For example, an example embodiment can include a generally circular through-hole and a trench, channel, or recess that is generally square, rectangular, etc. over its outer extent when viewed from plan. Similarly, an example embodiment can include a generally rectangular or square through-hole and a trench, channel, or recess that is generally circular, oval, etc. over its outer extent when viewed from plan.

[0049] It should be understood that, in all embodiments, the recess need not extend entirely around the through-hole. Rather, multiple collapsible arms can be formed, for example, via multiple recesses. These multiple recesses can take different sizes and / or shapes, similar to that described in the preceding paragraph.

[0050] The technology of U.S. Patent 9,371,683 (the entirety of which is hereby incorporated by reference) can be used to seal an integral tube, for example, by tracing a smaller and smaller circle or other connected pattern around the tube adjacent the sidewall / sealing arm so as to relax the opposing edges of the sidewall / sealing arm toward one another and form a bridge (e.g., as shown in Figure 5 and Figure 7 The similar effect can be achieved using a progressively narrower width of the scan in the case where multiple separate sidewalls / sealing arms are provided. For example, one or more lasers can be used to scan along a first upwardly projecting sealing arm and a second upwardly projecting sealing arm so as to relax them toward one another. The lasers can be focused along scan lines or scan areas that are increasingly closer to one another, for example, as the relaxation continues to progress in the formation of the bridge.

[0051] Figure 8 is a flow diagram illustrating an example method for manufacturing a VIG unit with an internal pump-out tube according to certain example embodiments. In step S81, an internal port profile is formed in a first substrate, e.g., via one or more drilling operations, etc. In step S83, a spacer or pillar is placed on a second substrate. In step S85, a frit material is applied to a peripheral edge of the second substrate. In step S87, the first and second substrates are pinned together such that a cavity is formed therebetween, and a hermetic edge seal is formed in step S89 (e.g., via laser heating, heating in an oven, using an infrared heater, etc.). In step S91, the cavity is evacuated to a pressure less than atmospheric pressure. For example, while maintaining the vacuum, the internal tube is optionally pre-heated in step S93. This can be achieved using an oven, using an infrared heater, via a laser, etc. Core heating is performed in step S95, and tube slot heating is repeatedly performed in step S97 until the tube is sealed (e.g., as indicated by step S99). The core heating process of step S95 provides the majority of the melting process, while the tube slot heating of step S97 is provided with progressively smaller perimeters, areas, etc., e.g., depending on the configuration of the tube, sidewall / seal arms, through-holes, relaxation in progress, etc. Once sealed, the unit can be moved in step S101 for further processing.

[0052] As will be appreciated from the foregoing, the internal seal is not limited to the use of a separate glass tube. As noted above, in certain example embodiments, an integrated tube formed from one of the substrates itself can be used. Further, certain example embodiments can utilize a hermetic sealing material (e.g., a metal solder) that can withstand VIG processing temperatures and that can be placed into a VIG subassembly to facilitate sealing of the pump-out port from the inside. For example, Figure 9 is a cross-sectional schematic illustrating another method of sealing a pump-out port according to certain example embodiments. As shown, Figure 9 a metal or other disc 90 is disposed in the cavity. The disc 90 has solder disposed on its surface that is intended to cooperate with the recess formed in the substrate 3. In certain example embodiments, the solder can be shaped sufficient to allow the evacuation of gas through the port. Additionally or alternatively, in certain example embodiments, the disc 90 can be held "above" the pump port during evacuation via one or more magnets 92, allowing for the expulsion of air and / or contaminant material. The disc 90 and / or the solder applied thereto can be heated via induction (e.g., using an induction coil 94), laser, or other means, e.g., to seal the pump-out port from the inside.

[0053] Figure 10 is a flow diagram illustrating another example method for manufacturing a VIG unit with an internal seal according to certain example embodiments.Figure 10 In many respects similar to Figure 8 For example, in step S81, an internal pump-out tube profile is formed in the first substrate, e.g., via one or more drilling operations, etc. In step S83, a spacer or post is placed on the second substrate. In step S85, a frit material is applied to the peripheral edge of the second substrate. However, unlike Figure 8 In step S103, a disc is placed onto the second substrate (e.g., adjacent to the forming port). The disc can have frit or other sealing material applied thereto prior to being placed on the second substrate. Again, similar to Figure 8 In step S87, the first and second substrates are staked together such that a cavity is formed therebetween (e.g., with the disc located in the cavity), and in step S89, a hermetic edge seal is formed (e.g., via laser heating, heating in an oven, using an infrared heater, etc.). In step S105, the magnet is activated to lift the disc. In step S91, the cavity is evacuated to a pressure less than atmospheric pressure. In step S107, the disc is released, and in step S109, it is heated. Once sealed, the unit can be moved for further processing in step S101.

[0054] It should be appreciated that Figure 8 And The steps in the example methods of Figure 10 may be performed by different parties in any suitable order, and / or additional steps can be provided in different example embodiments. For example, a different party than the party sealing the VIG and / or port can form the hole. In certain example embodiments, forming a tube profile in the first substrate can be performed, the first and / or second substrates can be tempered, the frit can be applied to the peripheral edge of the first and / or second substrate, the spacer can be placed, and then other operations can be performed, e.g., as shown in these figures.

[0055] In certain example embodiments, where a separate tube is provided, the diameter or major distance of the through hole can be 0.5 mm - 5 mm, more preferably the diameter or major distance is 1 mm - 3 mm, and still more preferably the diameter or major distance is 1.5 mm - 2.6 mm. In certain example embodiments, where an integral or unitary tube is provided, the diameter or major distance of the through hole can be 0.5 mm - 5 mm, more preferably the diameter or major distance is 1.5 mm - 4 mm, and still more preferably the diameter or major distance is 2 mm - 3.5 mm. In example embodiments using a tube, the width or major distance of the tube can be slightly smaller (e.g., 0.1 mm - 1 mm smaller in width or major distance). In certain example embodiments, the tube sidewall thickness can be 0.2 mm - 0.5 mm thick, more preferably 0.25 mm - 0.45 mm thick.

[0056] Any suitable laser can be used for sealing. For example, a 1064 nm wavelength laser operating at 10-30 watts, more preferably 20-30 watts, can be used. With such lasers and diameters, it has been found that the tube can be sealed by burning through the float glass, and requires about 10-30% more energy than to seal the tube unimpeded. In different example embodiments, the increase can be provided in time and / or power.

[0057] In certain example embodiments using a sealing disk or the like, the diameter or major distance of the through hole will preferably be 4-5 mm. The disk is preferably about twice the size of the hole. For example, in certain example embodiments, the diameter or major distance of the disk can be about 7-10 mm. In certain example embodiments, the disk can be made of a ferromagnetic material that will have a layer of solder or metal that will melt onto the inner surface when heated.

[0058] It should be appreciated that the technology disclosed herein can be used for a wide variety of applications, including, for example, VIG window applications, merchandisers, laminated products, hybrid VIG units (e.g., units in which a substrate is spaced apart from a VIG unit via a spacer system), and the like.

[0059] As used herein, the terms "heat treatment" and "heat treating" mean heating an article to a temperature sufficient to achieve thermal tempering and / or thermal strengthening of the article comprising glass. This definition includes, for example, heating the coated article in an oven or furnace at a temperature of at least about 550 °C, more preferably at least about 580 °C, more preferably at least about 600 °C, more preferably at least about 620 °C, and most preferably at least about 650 °C, for a period of time sufficient to allow tempering and / or thermal strengthening. In certain example embodiments, this can be for at least about two minutes, or up to about 10 minutes. These processes can be adapted to involve different times and / or temperatures.

[0060] As used herein, unless expressly stated otherwise, the terms "on," "supported by," and the like are not to be construed as meaning that two elements are directly adjacent to one another. In other words, a first layer can be said to be "on" or "supported by" a second layer even though there is one or more layers between them.

[0061] In certain example embodiments, a method of manufacturing a vacuum insulated glass (VIG) unit is provided. A first glass substrate and a second glass substrate are provided, with the second substrate including a hole formed therein, with the hole formed to have a first portion and a second portion, with the first portion closer to an outer surface of the second substrate than the second portion, with the first portion having a first width across the second substrate and the second portion having a second width across the second substrate, and with the first width narrower than the second width, the first portion and the second portion together forming a through-hole through the second substrate. A pump-out tube is placed in the hole. The first substrate and the second substrate are sealed together with an edge seal disposed around a peripheral edge of the first substrate and / or the second substrate, with a cavity defined by the first substrate and the second substrate, with a plurality of spacers disposed in the cavity between the first substrate and the second substrate and facilitating maintaining the first substrate and the second substrate in a spaced apart relationship substantially parallel to each other. The cavity is evacuated to a pressure less than atmospheric pressure. The pump-out tube is heated to collapse a portion of the tube adjacent the first substrate inward on itself to cover the second width and hermetically seal the VIG unit and form a sealed tube, with the sealed tube entirely inside the VIG unit.

[0062] In addition to the features of the preceding paragraph, in certain example embodiments, the first portion and the second portion of the hole can be formed via drilling.

[0063] In addition to the features of either of the preceding two paragraphs, in certain example embodiments, the pump-out tube can be sealed to the second substrate using a glass frit material provided to the pump-out tube and / or the second substrate.

[0064] In addition to the features of any of the preceding three paragraphs, in certain example embodiments, the hole can include a stepped portion formed in the first portion, e.g., with the stepped portion sized, shaped, and arranged to support the pump-out tube during sealing of the first substrate and the second substrate together by heating the pump-out tube.

[0065] In addition to the features of any of the preceding four paragraphs, in certain example embodiments, the second portion can form at least a portion of a pocket in the second substrate. For example, a getter material can be provided to the pocket.

[0066] In addition to the features of any of the preceding four paragraphs, in certain example embodiments, the heating can be laser heating.

[0067] In addition to the features of the preceding paragraph, in certain example embodiments, the laser heating is practiced so as to preferentially heat the pump-out tube relative to the first substrate.

[0068] In addition to the features of any of the preceding two paragraphs, in certain example embodiments, the heating can be performed in conjunction with a laser placed on an opposite side of the first substrate from the second substrate such that the laser emits energy through the first substrate.

[0069] In addition to the features of any of the preceding three paragraphs, in certain example embodiments, the laser heating can include tracking a collapsed portion of the tube as the tube collapses inward on itself during formation of the sealed tube.

[0070] In certain example embodiments, a method of manufacturing a vacuum insulating glass (VIG) unit subassembly is provided. A second glass substrate is provided, where the second substrate includes a hole formed therein, where the hole is formed to have a first portion and a second portion, where the first portion is closer to an outer surface of the second substrate than the second portion, where the first portion has a first width across the second substrate and the second portion has a second width across the second substrate, where the first width is narrower than the second width, and where the first portion and the second portion together form a through-hole through the second substrate. The second substrate is transferred to another party to: place a pump-out tube in the hole; seal a first glass substrate together with the second substrate in conjunction with an edge seal disposed around a peripheral edge of the first substrate and / or the second substrate, a cavity being defined by the first substrate and the second substrate, a plurality of spacers disposed in the cavity between the first substrate and the second substrate, and facilitating maintaining the first substrate and the second substrate in a spaced apart relationship substantially parallel to each other. Evacuate the cavity to a pressure less than atmospheric pressure; and laser heat the pump-out tube so as to collapse a portion of the tube adjacent to the first substrate inward on itself to cover the second width and hermetically seal the VIG unit and form a sealed tube, the sealed tube being entirely inside the VIG unit.

[0071] In addition to the features of the preceding paragraph, in certain example embodiments, the first portion and the second portion of the hole can be formed via drilling.

[0072] In addition to the features of any of the preceding two paragraphs, in certain example embodiments, the second portion can form at least a portion of a recess in the second substrate.

[0073] In addition to the features of any of the preceding three paragraphs, in certain example embodiments, the laser heating is practiced so as to preferentially heat the pump-out tube relative to the first substrate.

[0074] In addition to the features of any of the preceding four paragraphs, in certain example embodiments, the laser heating can be performed in conjunction with a laser placed on an opposite side of the first substrate from the second substrate such that the laser emits energy through the first substrate.

[0075] Certain example embodiments are directed to a vacuum insulating glass (VIG) unit made by the method of any of the preceding 14 paragraphs.

[0076] In certain example embodiments, a vacuum insulating glass (VIG) unit is provided, including a first glass substrate and a second glass substrate maintained in a spaced apart relationship substantially parallel to each other via a hermetic edge seal and a plurality of spacers disposed in a cavity defined between the first glass substrate and the second glass substrate, the cavity evacuated to a pressure less than atmospheric pressure using a pump-out port hermetically sealed with a laser-seal tube, the laser-seal tube including a sealed portion adjacent the cavity fabricated therefrom, the laser-seal tube located inside the VIG unit and not protruding therefrom.

[0077] In addition to the features of the preceding paragraph, in certain example embodiments, the tube can be connected to the second substrate of the VIG unit via a frit material.

[0078] In addition to the features of any of the preceding two paragraphs, in certain example embodiments, the getter can be disposed on an opposite side of the laser-seal tube in a pocket formed in the second substrate.

[0079] In addition to the features of any of the preceding three paragraphs, in certain example embodiments, the tube can be located on a stepped portion of the pump-out port.

[0080] In certain example embodiments, a method of manufacturing a vacuum insulating glass (VIG) unit is provided. The method includes having a first glass substrate and a second glass substrate, the second substrate including a through-hole formed therein. A cover is placed over the hole on the second glass substrate. The first substrate and the second substrate are sealed together in conjunction with an edge seal disposed around a peripheral edge of the first substrate and / or the second substrate, a cavity is defined by the first substrate and the second substrate, a plurality of spacers are disposed in the cavity between the first substrate and the second substrate and facilitate maintaining the first substrate and the second substrate in a spaced apart relationship substantially parallel to each other, the cover is disposed between the first substrate and the second substrate. The cavity is evacuated to a pressure less than atmospheric pressure. After the evacuation, the cover is connected to an interior surface of the second substrate and hermetically seals the VIG unit, the cover being entirely inside the VIG unit.

[0081] In addition to the features of the preceding paragraph, in certain example embodiments, the cover can be sealed to the second substrate using a frit material provided to the cover and / or the second substrate.

[0082] In addition to the features of either of the preceding two paragraphs, in certain example embodiments, the cover can also be magnetic, and the method can further include lifting the cover using a magnet during the evacuating; and allowing the cover to rest on the second substrate after the evacuating in preparation for sealing the cover to the second substrate.

[0083] In addition to the features of any of the preceding three paragraphs, in certain example embodiments, a recess can be provided in the second substrate around the through-hole and on an example of the second substrate facing the first substrate, e.g., where the recess has a getter provided thereto.

[0084] In addition to the features of any of the preceding four paragraphs, in certain example embodiments, the connecting can be practiced by engaging an induction coil. For example, the induction coil can be provided on an example of the second substrate opposite the first substrate.

[0085] In addition to the features of any of the preceding five paragraphs, in certain example embodiments, the connecting can be practiced by heating the cover and / or a region adjacent thereto.

[0086] In addition to the features of the preceding paragraph, in certain example embodiments, the heating can be laser heating.

[0087] In addition to the features of the preceding paragraph, in certain example embodiments, the laser heating is practiced so as to preferentially heat the cover and / or a frit material applied thereto relative to the first substrate.

[0088] In addition to the features of any of the preceding three paragraphs, in certain example embodiments, the heating can be performed in conjunction with a laser placed on an example of the first substrate opposite the second substrate such that the laser emits energy through the first substrate.

[0089] Certain example embodiments are directed to a vacuum insulating glass (VIG) unit made by a method according to any of the preceding nine paragraphs.

[0090] In certain example embodiments, a vacuum insulating glass (VIG) unit is provided, including a first glass substrate and a second glass substrate maintained in spaced apart, substantially parallel relationship to one another via a hermetic edge seal and a plurality of spacers disposed in a cavity defined between the first and second glass substrates, the cavity evacuated to a pressure less than atmospheric pressure using a pump-out port hermetically sealed with a cover disposed in the cavity without protruding from the VIG unit.

[0091] In addition to the features of the preceding paragraph, in certain example embodiments, the cover can be connected to the second substrate of the VIG unit via a frit material.

[0092] In addition to the features of either of the preceding two paragraphs, in certain example embodiments, a getter can be disposed on opposite sides of the port formed in the recess in the second substrate.

[0093] While this application has been described in connection with the embodiments shown, it will be understood that it is not limited to any disclosed embodiment but is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A method for manufacturing a vacuum-insulating glass (VIG) unit, the method comprising: It has a first glass substrate and a second glass substrate, the second glass substrate including a through hole formed therein; The cover is placed on the through hole on the second glass substrate; An edge seal is used to seal a first glass substrate and a second glass substrate together, the edge seal being disposed near the peripheral edge of the first glass substrate and / or the second glass substrate, a cavity being located between at least the first glass substrate and the second glass substrate, a plurality of spacers being disposed in the cavity between at least the first glass substrate and the second glass substrate and helping to maintain the first glass substrate and the second glass substrate in a substantially parallel and spaced-apart relationship, and a cover being disposed between at least the first glass substrate and the second glass substrate; The cavity is evacuated to a pressure less than atmospheric pressure; as well as After the evacuation, the cover is attached to the inner surface of the second glass substrate and the VIG unit is hermetically sealed, with the cover completely inside the VIG unit; Wherein, the cover is magnetic and the method further includes: The cover is lifted using a magnet during the evacuation process; and After the evacuation, the cover is allowed to rest on the second glass substrate in preparation for sealing the cover to the second glass substrate.

2. The method according to claim 1, further comprising: The cover is sealed to the second glass substrate using a glass frit material provided to the cover and / or the second glass substrate.

3. The method according to claim 1, wherein, A recess is provided in the second glass substrate around the through hole and on the side of the second glass substrate facing the first glass substrate, the recess having a getter provided to the recess.

4. The method according to claim 1, wherein, The connection is implemented using an induction coil.

5. The method according to claim 4, wherein, The induction coil is disposed on the side of the second glass substrate opposite to the first glass substrate.

6. The method according to any one of claims 1 to 5, wherein, The connection is achieved by heating the cover and / or the area adjacent to the cover.

7. The method according to claim 6, wherein, The heating includes laser heating.

8. The method according to claim 7, wherein, The laser heating is practiced to preferentially heat the cover and / or the glass frit material applied to the cover relative to the first glass substrate.

9. The method according to claim 6, wherein, The heating is performed using a laser placed on the side of the first glass substrate opposite to the second glass substrate, such that the laser emits energy through the first glass substrate.

10. A vacuum-insulated glass (VIG) unit, comprising: A first glass substrate and a second glass substrate, the first glass substrate and the second glass substrate being maintained in a substantially parallel and spaced-apart relationship via an hermetically sealed edge seal and a plurality of spacers disposed in a cavity defined between the first glass substrate and the second glass substrate, the cavity being evacuated to a pressure less than atmospheric pressure using a pump outlet port, the pump outlet port being hermetically sealed with a cover, the cover being disposed in the cavity without protruding from the VIG unit, wherein the cover is magnetic and is lifted using a magnet during the evacuation, and after the evacuation, the cover is allowed to rest on the second glass substrate in preparation for sealing the cover to the second glass substrate.

11. The VIG unit according to claim 10, wherein, The cover is connected to the second glass substrate of the VIG unit via a glass frit material.

12. The VIG unit according to any one of claims 10 to 11, further comprising: A getter is disposed on the opposite side of the port formed in a recess in the second glass substrate.

13. A vacuum-insulated glass (VIG) unit manufactured by the method according to claim 1.

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