Vacuum glass and preparation method therefor

Abstract

Disclosed in the present invention are vacuum glass and a preparation method therefor. The method comprises: grinding a corner portion on the back surface of each of two glass sheets to form a notch; tempering the two glass sheets, applying first solder to the outer edge of the back surface of each of the glass sheets, and forming a gap; merging the two glass sheets; performing first sealing on the merged two glass sheets; placing a getter in a cavity between the two glass sheets through the gap on a sealing frame; sintering second solder to form an insert and placing the insert into the notch, one end of the insert being configured towards the cavity; mounting an elastic pressing device on the two glass sheets, the elastic pressing device elastically pressing against the other end of the insert; and sequentially performing vacuumizing and second sealing on the two glass sheets, so that a vacuum is formed in the cavity, and melting the second solder to seal the notch. The present invention solves the problem that, in existing preparation methods for vacuum glass, solder at an edge portion is prone to foaming when heated at high temperature under vacuum.

Description

Vacuum Glass and its Preparation Method Technical Field

[0001] This invention relates to the field of vacuum glass technology, and more specifically to a vacuum glass and its preparation method. Background Technology

[0002] Vacuum glass consists of two panes of glass sealed around the edges and separated by thin supports, with a vacuum in the middle. Due to the vacuum layer, vacuum glass possesses excellent thermal insulation and sound insulation properties, and is extremely thin and lightweight; furthermore, the excellent airtightness and sealing strength of the surrounding welds contribute to its superior performance. Based on these characteristics, vacuum glass is widely used in industries such as energy-efficient building doors and windows, and energy-efficient glass doors for refrigerators.

[0003] Existing vacuum glass manufacturing methods (such as Chinese patent CN104030557B) mitigate the impact of edge venting on vacuum levels, but still fail to address the issues of foaming of the edge solder during high-temperature heating under vacuum and the need for double high-temperature annealing. Furthermore, the sealing solder, placed outside the glass, cannot fully wet the glass surface before reaching the sealing temperature and is difficult to press into the micro-vacuum layer to form an effective seal width. Once the sealing solder softens to a molten state, the lack of external constraint makes it prone to foaming. The sealing device is fixed to a mechanism outside the glass, restricting the glass placement and hindering continuous mass production.

[0004] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0005] To overcome the shortcomings of existing technologies, a vacuum glass and its preparation method are provided to solve the problem that existing vacuum glass preparation methods are prone to foaming when the edge solder is heated at high temperatures under vacuum.

[0006] To achieve the above objectives, a method for preparing vacuum glass is provided, comprising:

[0007] Two glass plates are provided, each glass plate having a front side and a back side, and a notch is formed by grinding one corner of the back side of the glass plate.

[0008] The two glass plates are tempered and a first solder is applied to the outer edge of the back side of the glass plates. The first solder is arranged in a circle along the circumferential direction of the glass plates, and a notch is formed in the circle of the first solder. The notch is located at the notch position.

[0009] The two glass plates are joined together so that their back sides face each other.

[0010] Under normal pressure, the two glass plates after being laminated are sealed for the first time, so that the first solder melts to form a sealing frame bonded between the back sides of the two glass plates;

[0011] The getter is placed into the cavity between the two glass plates through the notch on the sealing frame;

[0012] The second solder is sintered to form a patch and inserted into the notch. One end of the patch faces the cavity. The sealing temperature of the second solder is lower than that of the first solder and the temperature difference is less than 150°C.

[0013] An elastic pressure device is installed on the two glass plates, and the elastic pressure device is elastically pressed against the other end of the insert;

[0014] The two glass plates are sequentially evacuated and then sealed a second time, creating a vacuum inside the cavity, and the second solder melts to seal the gap.

[0015] Furthermore, the notch has an inner side facing the center of the plane of the glass plate and an outer side facing away from the center of the plane, and the width of the notch gradually decreases from the outer side of the notch to the inner side of the notch.

[0016] Furthermore, the back sides of the two glass plates are respectively formed with the notches.

[0017] Furthermore, a solder transition layer is provided between the first solder and the back of the glass plate.

[0018] Furthermore, a limiting groove is formed on the back of the glass plate, one end of the limiting groove is connected to the notch, and the getter is contained in the limiting groove.

[0019] Furthermore, the elastic pressure device includes:

[0020] A pressure bar abuts against the side of the glass sheet away from the insert, and the opposite ends of the pressure bar are bent to form two limbs, the ends of which extend to the outside of the other side of the glass sheet near the insert.

[0021] A reaction plate is installed in an adjustable position at the ends of the two limb rods;

[0022] A pressure plate is elastically installed on one side of the reaction plate facing the other side of the glass sheet. An inner liner plate is connected to the inner side of the pressure plate. A socket groove is formed on the inner liner plate. The other side of the glass sheet near the insert is embedded in the socket groove, and the insert abuts against the bottom of the socket groove.

[0023] Furthermore, the reaction plate has first through holes at its opposite ends, and the ends of the two limbs are movably inserted into the first through holes. The ends of the limbs are formed with external threads, and the ends of the limbs are screwed with threaded parts, which press against the other side of the reaction plate.

[0024] Furthermore, a second through hole is provided on each of the opposite sides of the pressure plate, and the two limb rods are movably inserted into the second through hole of the pressure plate.

[0025] Furthermore, during the first and second sealing processes, the wavelength of the infrared heating tube in the heating device of the sealing chamber is 1050–1100 nm.

[0026] This invention provides a vacuum glass, which is prepared using the aforementioned vacuum glass preparation method.

[0027] The beneficial effects of this invention are as follows: In the vacuum glass preparation method of this invention, pre-sealing the edges under atmospheric conditions followed by lamination and heating allows sufficient time for the solder to fully wet the glass. When the welding temperature is reached, the solder and glass temperatures are the same, which enhances the sealing strength. In the vacuum glass preparation method of this invention, after the pre-sealed edges cool, a getter is inserted through a notch, preventing oxidation of the getter at high atmospheric temperatures and improving its service life. In the vacuum glass preparation method of this invention, only one high-temperature heating is needed to seal and activate the getter, reducing edge stress during annealing. In the vacuum glass preparation method of this invention, the insert is in prolonged and sufficient contact with the glass under the action of the elastic pressure module, and the temperature of the insert and the contact glass is the same during sealing, improving the sealing strength. The insert is under the action of the pressure module from the softening temperature to the welding temperature and then to the completion of the process, preventing solder foaming. The second local edge sealing in the vacuum glass preparation method of this invention has a small heating area, minimizing the impact on glass surface stress. The vacuum glass preparation method of this invention, by pre-sealing the edges under atmospheric conditions, effectively avoids the disadvantages of high-temperature solder foaming and gas release under vacuum, contributing to improved vacuum level and welding strength. The vacuum glass preparation method of the present invention uses an elastic pressure device and an insert fixed on the glass, which can move freely with the glass. In addition, the heating tube of the vacuum sealing chamber automatically selects local heating. During production, the glass can be placed arbitrarily on the support frame according to the glass size. The equipment has a high loading rate, improves the production efficiency of the vacuum production line, and is suitable for mass production. Attached Figure Description

[0028] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0029] Figures 1 to 7 are schematic diagrams illustrating the steps of the vacuum glass preparation method according to an embodiment of the present invention.

[0030] Figure 8 is a schematic diagram of the elastic pressurization device according to an embodiment of the present invention.

[0031] Figures 9 to 11 are schematic diagrams of three forms of the notch in embodiments of the present invention.

[0032] Figure 12 is a schematic diagram of the state of the getter in the limiting groove according to an embodiment of the present invention.

[0033] Figure 13 is a schematic diagram of the state of the getter under the limitation of the strip ink according to an embodiment of the present invention.

[0034] Figure 14 is a schematic diagram of the solder transition layer layout according to an embodiment of the present invention. Detailed Implementation

[0035] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0036] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0037] Referring to Figures 1 to 14, the present invention provides a method for preparing vacuum glass, comprising the following steps:

[0038] S1. Referring to Figure 1, two glass plates 1 are provided. Each glass plate 1 has a front side and a back side. A notch 10 is formed by grinding one corner of the back side of the glass plate 1.

[0039] The notch is designed to run the length or width of the glass sheet. The length of the notch is adapted to the length or width of the glass sheet. Smaller notches, after grinding, can easily cause the glass half to break due to stress concentration on either side of the notch.

[0040] In a preferred embodiment, the notch 10 has an inner side facing the center of the plane of the glass plate 1 and an outer side facing away from the center of the plane. Referring to Figures 9 to 11, the width of the notch 10 gradually decreases from the outer side to the inner side of the notch 10. The grinding surface of the notch is a bevel (as shown in Figure 1), a plane (as shown in Figure 9), or an arc surface (a concave arc surface as shown in Figure 10 and a convex arc surface as shown in Figure 11).

[0041] In some embodiments, notches 10 are formed on the back sides of the two glass plates 1 respectively.

[0042] Specifically, a portion of one side of a glass sheet or the same side of two glass sheets is ground off to create a notch with a thickness less than the thickness in the middle of the glass.

[0043] The width of the notch edge in the plane direction of the glass plate is 5 to 20 mm, and the grinding height in the thickness direction of the glass plate is 0.5 to 2.5 mm.

[0044] S2. Temper the two glass plates 1 and apply the first solder 2 to the outer edge of the back side of the glass plates 1. The first solder 2 is arranged in a circle along the circumferential direction of the glass plates 1. The circle of the first solder 2 forms a notch 20, and the notch 20 is located at the notch 10 position.

[0045] Before the glass plates are tempered, a support member 11 is placed on one of the glass plates, and then the two glass plates are sent into the tempering furnace for tempering, and the support member 11 is sintered on the glass plates.

[0046] After the glass plates are tempered, the first solder is applied to the notch edge of one of the glass plates and the remaining edges, and a notch 20 is reserved in the solder frame at one or both ends of the notch edge.

[0047] The width of the notch is 5-50 mm, and the starting point is 0-60 mm away from the side surface of the adjacent glass plate.

[0048] As a preferred embodiment, referring to Figure 14, a solder transition layer 6 is provided between the first solder 2 and the back surface of the glass plate 1. The solder transition layer has a composition similar to the first solder and its coefficient of thermal expansion is between that of glass and the first solder. The solder transition layer is made of low-melting-point glass powder or a metallic material.

[0049] Before applying the solder, a solder transition layer can be applied around one or two glass plates. After the glass plates are tempered, the first solder is applied to the solder transition layer to enhance the sealing strength between the first solder and the glass.

[0050] S3. Join the two glass plates 1 together so that the back sides of the two glass plates 1 are facing each other.

[0051] Two pieces of tempered glass with support members and the first solder are joined together, and high-temperature clamps are arranged around them.

[0052] S4. Under normal pressure, the two glass plates 1 after being assembled are sealed for the first time, so that the first solder 2 melts to form a sealing frame bonded between the back sides of the two glass plates 1.

[0053] Under normal pressure (i.e. atmospheric pressure), the assembled glass sheets are fed into a continuous edge sealing furnace. After preheating, glue removal, sealing, and cooling, the first sealing of the edges of the glass sheets is completed. A notch is formed in the sealing frame at the corner of the notch, which is larger than the height of the sealing frame of the support. The first solder is applied to the parts of the notch edge other than the notch.

[0054] Under normal pressure, the solder is less likely to produce bubbles during sealing.

[0055] S5. Place the getter 3 into the cavity between the two glass plates 1 through the notch 20 on the sealing frame.

[0056] The getter is placed into the vacuum layer between the two glass plates through the notch. After the first sealing, the getter is placed in to prevent oxidation of the getter due to high temperature in the atmosphere.

[0057] In a preferred embodiment, referring to FIG12, a limiting groove is formed on the back side of the glass plate 1. The limiting groove communicates with the notch. One end of the limiting groove is connected to the notch 20. The getter is contained in the limiting groove.

[0058] The getter is inserted into the pre-made limiting groove on the inner surface of the glass plate through the notch of the sealing frame. One end of the limiting groove of a glass plate is connected to the notch of the sealing frame to facilitate the placement of more getter.

[0059] The limiting groove can be formed by grinding the inner side of the glass plate, or by forming two opposing ridges 9 on the inner side of the glass plate.

[0060] Referring to Figure 13, the getter can also be inserted from the sealing frame into the channel formed by one or two thin strips of ink 31 prefabricated on the glass surface to prevent displacement when inserting the getter.

[0061] The getter can be one or both non-evaporable and evaporable, and can also be activated after the vacuum glass is made.

[0062] S6. The second solder is sintered to form an insert 4 and inserted into the notch 20. One end of the insert 4 is set towards the cavity. The sealing temperature of the second solder is less than the sealing temperature of the first solder 2 and the temperature difference is less than 150℃.

[0063] In this embodiment, the length of the notch edge is less than or equal to the side length of the edge being greater than or equal to the solder frame notch, forming a notch to accommodate the insert and facilitate processing. The insert can be cylindrical, cuboid, spherical, or wedge-shaped.

[0064] In this embodiment, the insert is wedge-shaped.

[0065] The second solder is pre-sintered into a solid insert and filled into the notch 20 of the sealing frame. The other end of the insert protrudes above the side of the glass plate, and there is a gap between the insert and the sealing frames and glass on both sides to form an air extraction channel connecting the inside and outside of the glass plate. Placing the insert into the notch facilitates the solder to fully contact the glass surface inside the notch after heating and softening, and to form an effective sealing width.

[0066] The insert can be one or more pieces.

[0067] The sealing temperature of the insert is less than or equal to the sealing temperature of the first solder, and the temperature difference is less than 150°C. This helps to reduce the annealing of the glass with local heating at the notch of the sealing frame and the impact on the sealing edge of the first solder.

[0068] The first and second solders are low-melting-point glass powder or metal solder.

[0069] S7. An elastic pressure device 5 is installed on the two glass plates 1, and the elastic pressure device 5 is elastically pressed against the other end of the insert 4.

[0070] In this embodiment, the elastic pressing device 5 includes: a pressing rod 51, a reaction plate 52, and a pressure plate 53.

[0071] The pressing rod 51 abuts against the side of the glass plate 1 away from the insert 4. The opposite ends of the pressing rod 51 are bent to form two limbs 511. The ends of the two limbs 511 extend to the outside of the other side of the glass plate 1 near the insert 4.

[0072] The reaction plate 52 is adjustablely installed at the end of the two limb rods 511.

[0073] The pressure plate 53 is elastically mounted on the side of the reaction plate 52 facing the glass plate 1. An inner liner plate 531 is connected to the inner side of the pressure plate 53. A socket groove is formed on the inner liner plate 531. The side of the glass plate 1 closest to the insert 4 is embedded in the socket groove. The insert 4 abuts against the bottom of the socket groove.

[0074] The reaction plate 52 has first through holes at its two opposite ends. The ends of the two limbs 511 are movably inserted into the first through holes. The ends of the limbs 511 are formed with external threads, and the ends of the limbs 511 are screwed with threaded parts 54. The threaded parts 54 press against the other side of the reaction plate 52.

[0075] The pressure plate 53 has a second through hole on each of its opposite sides. The two limb rods 511 are movably inserted into the second through holes of the pressure plate 53.

[0076] The pressure plate 53 is elastically mounted to the reaction plate 52 by a spring 55.

[0077] A spring-loaded elastic pressure device applies pressure to a pre-fabricated insert protruding above the glass edge, towards the notch in the sealing frame. The device can be fixed to the side of the glass sheet, and pressure is continuously applied to the insert until vacuum glass processing is complete. Pressure is applied throughout the time from the solder's initial softening to reaching the sealing temperature and until the glass sheet is finished. This facilitates thorough wetting and sealing of the solder and glass sheet surface, and reduces foaming. The elastic pressure device is fixed to the glass sheet and can move with it, allowing for unrestricted placement.

[0078] Referring to Figure 5, when placing the elastic pressurizing device, a shielding plate 7 can be covered outside the area that needs to be heated to reduce the impact of local heating; a high-temperature clamp is applied to the sealing frame in the area affected by local heating to reduce the impact of local heating.

[0079] S8. Vacuuming and second sealing are performed on the two glass plates 1 in sequence to create a vacuum in the cavity, and the second solder melts to seal the gap 20.

[0080] A glass plate equipped with an elastic pressurizing device is fed into multiple consecutive vacuum chambers for low-temperature preheating and vacuuming. Air inside the glass plate is extracted through the air extraction channel within the sealing frame notch. When the vacuum level and temperature reach a certain level, it enters the second edge sealing chamber. The heating device in the sealing chamber locally heats the insert and getter at the edge notch, softening the insert and gradually heating it to the sealing temperature. Under the action of the elastic pressurizing device, the solder is gradually pressed in and fully fills the notch, completing the second edge sealing.

[0081] Before the gap is sealed, the gas inside the glass is continuously discharged through the gradually narrowing gap, which can also activate the getter.

[0082] Finally, after gradual cooling and pressurization to atmospheric pressure, the vacuum glass is removed from the furnace and the elastic pressurization device is removed, completing the production of vacuum glass.

[0083] In this embodiment, the glass plate with the elastic pressure device can be fed into the vacuum chamber vertically or horizontally.

[0084] The preheating temperature of the glass plate with the elastic pressure device is less than or equal to the surface stress annealing temperature of the glass plate.

[0085] Referring to Figure 8, the heating device of the second edge sealing chamber consists of multiple infrared heating tubes 8 with light-concentrating reflective coatings arranged closely on one or both sides of the glass. Each infrared heating tube can be controlled individually, and the nearest one or more infrared heating tubes can be automatically activated according to the gaps in the sealing frames on the multiple glass plates on the support frame and the position of the getter.

[0086] The infrared heating tubes of the heating devices in the first and second edge sealing chambers have wavelengths ranging from 1050 to 1100 nm. Infrared heating in this band results in rapid temperature rise and reduces the degree of stress annealing on the glass surface.

[0087] In some embodiments, when the first solder is a 250°C metal solder and the second edge-sealing solder is a 230°C metal solder, since the solder temperature is low and the expansion coefficients of metal and glass differ greatly, a metal-glass sealing transition layer can be applied around one or two pieces of glass before solder coating. After tempering, the first solder is applied on the transition layer. The transition layer enhances the sealing strength between the metal solder and the glass. When the pressurizing device is placed, a high-temperature clamp can be applied simultaneously to the edge of the area affected by the local heating pipe. In addition to the notch and getter, a shielding plate is covered in other glass areas affected by the local heating pipe to reduce the impact of local heating on the first edge sealing strip. The getter is activated after the vacuum glass is manufactured.

[0088] This invention provides a vacuum glass, which is prepared using the aforementioned vacuum glass preparation method.

[0089] The vacuum glass of the present invention seals most of the edge of the glass plate at high temperature under atmospheric pressure, and seals a small part of the edge (i.e., the notch) at low temperature under vacuum. The elastic pressure device is conducive to the elimination of solder bubbles, which greatly reduces the possibility of foaming during high-temperature welding under vacuum and basically avoids foaming.

[0090] Because the second edge sealing only needs to seal a small portion under vacuum, and considering the placement and location of the getter, the second edge sealing only requires local heating of the glass plate, greatly reducing the impact of annealing on the overall tempered surface stress of the glass plate.

[0091] Because the flexible pressurization device is locked to the glass plate and its placement is unrestricted, production efficiency is greatly improved.

[0092]

[0093] The vacuum glass preparation method of the present invention involves pre-sealing the edges under atmospheric conditions, then assembling the sheets and heating them. This allows the solder and glass to be fully impregnated for a sufficient time, and the solder and glass reach the same temperature when the welding temperature is reached, which helps to enhance the sealing strength.

[0094] The vacuum glass preparation method of the present invention involves inserting a getter through a notch after pre-sealing and cooling, thereby avoiding oxidation of the getter due to high atmospheric temperatures and improving its service life.

[0095] The vacuum glass preparation method of the present invention has a base temperature of less than 290°C before the vacuum chamber is sealed, which greatly reduces the annealing of the glass.

[0096] The vacuum glass preparation method of the present invention only requires one high-temperature heating to seal and activate the getter, without the need for preheating to reduce edge stress annealing.

[0097] In the vacuum glass preparation method of this invention, the insert is fully immersed in the glass for a long time under the action of an elastic pressure module, and the temperature of the insert and the contact glass are the same during sealing, which improves the sealing strength. The insert is under the action of the pressure module from the softening temperature to the welding temperature and then to the completion of the manufacturing process, so the solder is not prone to foaming.

[0098] In the vacuum glass preparation method of the present invention, the thickness of the notch of the sealing frame is greater than that of the support and the pressure module, so that the solder forms a sufficiently wide welding band to enhance the sealing performance.

[0099] In the vacuum glass preparation method of the present invention, the welding temperature of the insert can be lower than that of the first solder, thereby reducing the impact of heating on the first solder.

[0100] The second local sealing step in the vacuum glass preparation method of the present invention has a small heating area and has little impact on the stress on the glass surface.

[0101] The vacuum glass preparation method of the present invention effectively avoids the disadvantages of high-temperature foaming and gas release of solder under vacuum by pre-sealing the edges under atmospheric conditions, which helps to improve the vacuum degree and welding strength.

[0102] The vacuum glass preparation method of the present invention uses an elastic pressure device and an insert fixed on the glass, which can move freely with the glass. In addition, the heating tube of the vacuum sealing chamber automatically selects local heating. During production, the glass can be placed arbitrarily on the support frame according to the glass size. The equipment has a high loading rate, improves the production efficiency of the vacuum production line, and is suitable for mass production.

[0103] To further illustrate the vacuum glass preparation method of the present invention in detail, the following examples are provided.

[0104] S11. Two glass plates 1 are provided, and a notch 10 is formed by grinding one corner of the back side of the glass plate 1.

[0105] A notch is ground along one entire edge of a glass plate, with a notch width of 12mm and a grinding amount of 1mm in the thickness direction.

[0106] S21. Temper the two glass plates 1 and coat the outer edge of the back side of the glass plates 1 with the first solder low melting point glass powder 2. The first solder 2 is arranged in a circle along the circumferential direction of the glass plates 1. The circle of the first solder 2 forms a notch 20, and the notch 20 is located at the notch 10 position.

[0107] After tempering, a first solder, low-melting-point glass powder, is applied to the edge and notch edge of one of the glass plates. Since the weld seam at the notch edge is larger than that at other edges, the amount of solder applied is twice that at other edges. The sealing temperature of the first solder is 430℃. A 10mm long notch is reserved in the first solder strip at one corner of the notch edge, with the starting point located inside the solder strip on the adjacent straight edge, 12mm from the adjacent glass edge.

[0108] S31. Join the two glass plates 1 together so that the back sides of the two glass plates 1 are facing each other.

[0109] Two tempered glass sheets with a 0.2mm high support 4 and a first solder 2 are joined together, and high-temperature clamps are arranged around them.

[0110] S41. The two glass plates 1 after being assembled are sealed for the first time, so that the first solder 2 melts and forms a sealing frame bonded between the back sides of the two glass plates 1.

[0111] After being preheated at 150℃, degummed at 350℃, and sealed at 430℃ in a continuous edge sealing furnace, the first sealing of the glass plate is completed. After cooling, a sealing frame notch is formed at the corner of the notch by the sealing strips on both sides and the two pieces of glass. The length is reduced to 6mm due to the melting and widening of the sealing strips on both sides, and the thickness is 1.2mm.

[0112] S51. Place the getter 3 into the cavity between the two glass plates 1 through the notch 20 on the sealing frame.

[0113] Insert a strip of getter, 0.15 mm thick and 5 mm wide, into the vacuum layer through the notch.

[0114] S61. The second solder low-melting-point glass powder is sintered to form an insert 4 and inserted into the notch 20, with one end of the insert 4 facing the cavity.

[0115] The pre-fabricated, sintered insert of a second type of low-melting-point glass powder is filled into the notch at the edge of the gap. The sealing temperature of this insert is 380°C. The length, width, and height of the sealing frame are slightly smaller than the notch to form an air extraction channel connecting the inside and outside of the glass. The insert protrudes above the edge of the glass sheet. Placing the insert into the notch facilitates the solder to fully contact the glass surface inside the notch after heating and softening, thus forming an effective sealing width.

[0116] S71. An elastic pressure device 5 is installed on the two glass plates 1, and the elastic pressure device 5 is elastically pressed against the other end of the insert 4.

[0117] Maintaining a certain pressure throughout the time from when the solder begins to soften until it reaches the sealing temperature and the vacuum glass fabrication is completed is beneficial for the solder to fully wet and seal the glass surface and to prevent the solder from foaming under vacuum.

[0118] S81. Vacuuming and second sealing are performed on the two glass plates 1 in sequence to create a vacuum in the cavity, and the second solder melts to seal the gap 20.

[0119] Place the glass plate with the elastic pressure device on the support frame. When placing it, the direction of the getter in the notch is parallel to the direction of the heating pipe in the sealing chamber behind. In addition to the notch and getter, cover other glass areas that can be affected by the local heating pipe with a shielding plate to reduce the impact of local heating on the surface stress of other glass areas.

[0120] Then it is sent into multiple consecutive vacuum chambers for cryogenic preheating and vacuuming. The cryogenic preheating and vacuuming are carried out in multiple vacuum chambers, and the temperature and vacuum level are gradually increased. When the vacuum level reaches 10... - When the pressure reaches 3 Pa and the temperature reaches 280°C, the material enters the sealing chamber. The infrared heaters in the sealing chamber are closely arranged. Based on the edge gaps of each piece of glass on the support frame and the location of the getter, the nearest heater is automatically selected for local heating. This softens the insert and gradually heats it to the sealing temperature of 380°C. Under the action of the pressure fixture, the solder is gradually pressed in and fully fills the gap, completing the second edge sealing and forming a vacuum layer. At the same time, the strip getter can also be activated.

[0121] Finally, after gradually cooling and pressurizing to atmospheric pressure, the vacuum glass is removed from the furnace, thus completing the production of vacuum glass.

[0122] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A method for preparing vacuum glass, characterized in that, Includes the following steps: Two glass plates are provided, each glass plate having a front side and a back side, and a notch is formed by grinding one corner of the back side of the glass plate. The notch has an inner side facing the center of the plane of the glass plate and an outer side facing away from the center of the plane, and the width of the notch gradually decreases from the outer side of the notch to the inner side of the notch; The two glass plates are tempered and a first solder is applied to the outer edge of the back side of the glass plates. The first solder is arranged in a circle along the circumferential direction of the glass plates, and a notch is formed in the circle of the first solder. The notch is located at the notch position. The two glass plates are joined together so that their back sides face each other. Under normal pressure, the two glass plates after being laminated are sealed for the first time, so that the first solder melts to form a sealing frame bonded between the back sides of the two glass plates; The getter is placed into the cavity between the two glass plates through the notch on the sealing frame; The second solder is sintered to form a patch and inserted into the notch. One end of the patch faces the cavity. The sealing temperature of the second solder is lower than that of the first solder and the temperature difference is less than 150°C. An elastic pressure device is installed on the two glass plates, and the elastic pressure device is elastically pressed against the other end of the insert; The two glass plates are evacuated and then sealed a second time under vacuum, so that a vacuum is formed in the cavity, and the second solder melts to seal the gap; The elastic pressing device includes: a pressing rod abutting against the side of the glass plate away from the insert, the opposite ends of the pressing rod being bent to form two limbs, the ends of the two limbs extending to the outside of the other side of the glass plate near the insert; a reaction plate, positionably mounted on the ends of the two limbs; and a pressure plate elastically mounted on the side of the reaction plate facing the other side of the glass plate, the inner side of the pressure plate being connected to an inner liner plate, the inner liner plate having a socket groove, the other side of the glass plate near the insert being embedded in the socket groove, and the insert abutting against the bottom of the socket groove.

2. The method for preparing vacuum glass according to claim 1, characterized in that, The back sides of the two glass plates are respectively formed with the notches.

3. The method for preparing vacuum glass according to claim 2, characterized in that, A solder transition layer is provided between the first solder and the back of the glass plate.

4. The method for preparing vacuum glass according to claim 1, characterized in that, A limiting groove is formed on the back of the glass plate, one end of which is connected to the notch, and the getter is contained in the limiting groove.

5. The method for preparing vacuum glass according to claim 1, characterized in that, The reaction plate has a first through hole at each of its opposite ends. The ends of the two limbs are movably inserted into the first through hole. The ends of the limbs are formed with external threads. The ends of the limbs are screwed with a threaded engagement member, which presses against the other side of the reaction plate.

6. The method for preparing vacuum glass according to claim 5, characterized in that, The pressure plate has a second through hole on each of its opposite sides, and the two limb rods are movably inserted into the second through hole of the pressure plate.

7. The method for preparing vacuum glass according to claim 1, characterized in that, During the first and second sealing processes, the wavelength of the infrared heating tube in the sealing chamber is 900–1300 nm.

8. A vacuum glass, characterized in that, It is prepared by the vacuum glass preparation method according to any one of claims 1 to 7.

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