Vacuum glass and preparation method thereof

Abstract

The present invention discloses a vacuum glass and its preparation method. The steps include grinding a notch at a corner on one side of the back side of two glass plates; tempering the two glass plates and applying a first solder to the outer edge of the back side of the glass plates to form a notch; joining the two glass plates together; performing a first sealing on the joined glass plates; placing a getter into the cavity of the two glass plates through the notch on the sealing frame; sintering a second solder to form a patch and inserting it into the notch, with one end of the patch facing the cavity; installing an elastic pressure device on the two glass plates, the elastic pressure device elastically pressing against the other end of the patch; evacuating the two glass plates and performing a second sealing in sequence, so that a vacuum is formed in the cavity, and the second solder melts to seal the notch. The present invention solves the problem of the solder at the edge of the vacuum glass being easily foamed due to high temperature heating.

Description

Technical Field

[0001] The present invention relates to the technical field of vacuum glass, and in particular to vacuum glass and a preparation method thereof. Background Art

[0002] Vacuum glass consists of two sheets of glass sealed on all sides with a thin support between them, leaving a vacuum in the middle. This vacuum layer provides excellent thermal and sound insulation, and is very lightweight and thin. Furthermore, the solder around the edges provides excellent airtightness and sealing strength. These characteristics make vacuum glass widely used in energy-saving windows and doors for buildings, energy-saving glass doors for refrigerators, and other industries.

[0003] While existing vacuum glass production methods (such as Chinese Patent Publication No. CN104030557B) mitigate the impact of edge outgassing on the vacuum level, they still fail to address the issues of foaming and double-heat annealing during high-temperature heating of the edge solder under vacuum. 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 tiny vacuum layer to form an effective seal. Once the sealing solder softens to a molten state, it is free from external restraint and is prone to foaming. The sealing device is fixed to a mechanism outside the glass, limiting the glass placement and hindering continuous, mass production.

[0004] The information disclosed in this background technology section is only intended to enhance understanding of the overall background of the invention and should not be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the Invention

[0005] In order to overcome the defects of the existing technology, a vacuum glass and a preparation method thereof are provided to solve the problem that the solder at the lower edge of the vacuum is easily foamed when heated at high temperature in the existing vacuum glass preparation method.

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

[0007] Two glass sheets are provided, each of which has a front surface and a back surface, and a corner portion of one side of the back surface of the glass sheet is ground to form a notch;

[0008] Tempering the two glass sheets and applying a first solder on the outer edges of the back sides of the glass sheets, wherein the first solder is arranged in a circle along the circumference of the glass sheets, and a notch is formed in the circle of the first solder, wherein the notch is arranged at the position of the notch;

[0009] Putting the two glass sheets together so that the back surfaces of the two glass sheets face each other;

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

[0011] placing a getter into the cavity of the two glass sheets through the notch on the sealing frame;

[0012] Sintering a second solder to form an insert and inserting the insert into the notch, with one end of the insert facing the cavity, wherein the sealing temperature of the second solder is lower than the sealing temperature 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 elastically presses against the other end of the patch;

[0014] The two glass plates are sequentially vacuumed and sealed for a second time, so that a vacuum is formed in the cavity and the second solder is melted to seal the gap.

[0015] Furthermore, the notch has an inner side facing the plane center of the glass plate and an outer side facing away from the plane center, 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 notches are respectively formed on the back sides of the two glass plates.

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

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

[0019] Furthermore, the elastic pressure device includes:

[0020] a pressing rod abutting against a side of the glass sheet away from the patch, wherein opposite ends of the pressing rod are bent to form two limbs, and ends of the two limbs extend to the outside of the other side of the glass sheet close to the patch;

[0021] a reaction plate, mounted at the ends of the two limb rods in an adjustable manner;

[0022] A pressure plate is elastically mounted on one side of the reaction plate facing the other side of the glass plate, the inner side of the pressure plate is connected to an inner lining plate, a socket groove is formed on the inner lining plate, the other side of the glass plate close to the patch is embedded in the socket groove, and the patch rests against the bottom of the socket groove.

[0023] Furthermore, a first through hole is respectively provided at the opposite ends of the reaction plate, and the ends of the two limbs can be 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 screw parts, and the screw parts are pressed against the other side of the reaction plate.

[0024] Furthermore, second through holes are respectively opened on two opposite sides of the pressing plate, and the two limbs are movably inserted into the second through holes of the pressing plate.

[0025] Furthermore, during the first sealing and the second sealing, the wavelength of the infrared light heating tube of the heating device in the sealing chamber is 900 to 1300 nm.

[0026] The present invention provides a vacuum glass, which is prepared by adopting the above-mentioned vacuum glass preparation method.

[0027] The present invention provides advantageous effects, including that the vacuum glazing manufacturing method of the present invention utilizes atmospheric pre-sealing, prior to joining the sheets and then heating, to allow sufficient time for the solder to fully infiltrate the glass. When the welding temperature is reached, the solder and glass interface temperatures are at the same level, which enhances seal strength. In the vacuum glazing manufacturing method of the present invention, a getter is introduced through the gap after the pre-sealing has cooled, preventing oxidation of the getter by the high atmospheric temperature and improving service life. The vacuum glazing manufacturing method of the present invention requires only a single high-temperature heating step to seal and activate the getter, mitigating stress annealing at the edges. In the vacuum glazing manufacturing method of the present invention, the patching components, under the action of the elastic pressure module, maintain long-term contact and infiltration with the glass, and the contact surfaces of the patching components and the glass are at the same temperature during sealing, enhancing seal strength. The patching components are continuously subjected to the compression of the pressure module from softening temperature to welding temperature and then to completion, preventing solder foaming. The second partial edge sealing in the vacuum glazing manufacturing method of the present invention utilizes a small heating area, minimizing the impact on glass surface stress. The atmospheric pre-sealing method of the present invention effectively avoids the drawbacks of solder foaming and outgassing at high temperatures under vacuum, thereby enhancing vacuum and welding strength. The vacuum glass preparation method of the present invention adopts an elastic pressure device and a patch fixed on the glass, which can move arbitrarily with the glass. In addition, the heating tube in the vacuum sealing chamber automatically selects local heating. During production, the glass can be placed arbitrarily on the carrier according to the size of the glass. The equipment loading rate is high, the production efficiency of the vacuum production line is improved, and it is suitable for large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0029] Figures 1 to 7 Schematic diagram of the steps of a method for preparing vacuum glass according to an embodiment of the present invention.

[0030] Figure 8 Schematic diagram of the structure of the elastic pressure device according to an embodiment of the present invention.

[0031] Figures 9 to 11 Schematic diagrams of three forms of notches according to embodiments of the present invention.

[0032] Figure 12 This 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 This is a schematic diagram of the state of the getter in an embodiment of the present invention under the limitation of the strip ink.

[0034] Figure 14 Schematic diagram of the layout of the solder transition layer according to an embodiment of the present invention. DETAILED DESCRIPTION

[0035] The present application will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the relevant invention and are not intended to limit the invention. It should also be noted that, for ease of description, only portions relevant to the invention are shown in the accompanying drawings.

[0036] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

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

[0038] S1. See Figure 1 Two glass sheets 1 are provided, each of the glass sheets 1 having a front surface and a back surface, and a notch 10 is formed by grinding a corner portion of one side of the back surface of the glass sheet 1 .

[0039] In a preferred embodiment, the notch extends along the entire length or width of the glass sheet. The length of the notch is adapted to the length or width of the glass sheet. When the glass sheet is thin, a smaller notch can easily cause stress concentration at the notch after grinding, increasing the risk of damage to the glass sheet.

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

[0041] In some embodiments, a notch 10 is formed on the back surface of each of the two glass plates 1 .

[0042] Specifically, a portion of one side of a glass sheet or the same side of two glass sheets is ground off to form a notch edge in which the thickness of the edge is less than the thickness of 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 on 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. A notch 20 is formed in the circle of the first solder 2. The notch 20 is arranged at the position of the notch 10.

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

[0046] After the glass sheets are tempered, a first solder is applied inside the notch edge and on the remaining edges of one of the glass sheets, 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 to 50 mm, and the starting point is 0 to 60 mm away from the surface of the side of the adjacent glass plate.

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

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

[0050] S3. Put the two glass plates 1 together so that the back surfaces of the two glass plates 1 face each other.

[0051] The two pieces of tempered glass with the support 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 are sealed for the first time after being joined, so that the first solder 2 melts to form a sealing frame bonded between the back surfaces of the two glass plates 1 .

[0053] Under normal pressure (i.e. atmospheric pressure), the glass sheets after being joined are sent into a continuous edge sealing furnace for preheating, debinding, sealing and cooling to complete the first sealing of the edges of the glass sheets. A notch is formed in the sealing frame at the corner of the notch, and the notch is larger than the height of the support member. The first solder is coated on the other parts of the notch edge except the notch.

[0054] When sealing under normal pressure, solder is not prone to bubbles.

[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 gap, and the getter is placed after the first edge sealing to avoid high-temperature heating and oxidation of the getter in the atmosphere.

[0057] As a preferred embodiment, see Figure 12 A limiting groove is formed on the back of the glass plate 1. The limiting groove is connected to the notch. One end of the limiting groove is connected to the notch 20. A getter is accommodated in the limiting groove.

[0058] The getter is placed into the prefabricated limiting groove on the inner surface of the glass plate through the notch of the sealing frame. One end of the limiting groove on 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 forming two convex ridges 9 arranged opposite to each other on the inner side of the glass plate.

[0060] See Figure 13 As shown, the getter can also be placed from the sealing frame into a channel formed by one or two thin ink strips 31 prefabricated on the glass surface to prevent deviation when inserting the getter.

[0061] Getters are either non-evaporable or evaporable, or both, and can also be activated after the vacuum glass is fabricated.

[0062] S6. Sinter the second solder to form an insert 4 and insert it into the notch 20, with one end of the insert 4 facing the cavity. The sealing temperature of the second solder is lower than that of the first solder 2, and the temperature difference is less than 150°C.

[0063] In this embodiment, the length of the notch side is less than or equal to the side length and greater than or equal to the solder frame gap, forming a gap to accommodate the patch and facilitate processing. The patch is cylindrical, rectangular, spherical or wedge-shaped.

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

[0065] A second solder prefabricated and sintered solid patch is filled into the gap 20 of the sealing frame. The other end of the patch is higher than the side of the glass plate, and a gap is formed between the patch and the sealing frame and glass on both sides to form an exhaust channel connecting the inside and outside of the glass plate. Placing the patch into the gap facilitates the solder to fully contact the glass surface in the gap after heating and softening, thereby forming an effective sealing width.

[0066] The patch can be one piece or multiple pieces.

[0067] The sealing temperature of the patch is less than or equal to the sealing temperature of the first solder, and the temperature difference is less than 150° C., which is beneficial to reducing the annealing of the locally heated glass at the notch position of the sealing frame and the impact on the edge sealing of the first solder.

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

[0069] S7 . Install the elastic pressure device 5 on the two glass plates 1 . The elastic pressure device 5 elastically presses against the other end of the patch 4 .

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

[0071] The pressing rod 51 abuts against one side of the glass plate 1 away from the patch 4. 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 patch 4.

[0072] The reaction plates 52 are mounted at the ends of the two limb rods 511 in an adjustable manner.

[0073] The pressure plate 53 is elastically mounted on the side of the reaction plate 52 facing the other side of the glass sheet 1. An inner lining plate 531 is connected to the inner side of the pressure plate 53. A socket groove is formed in the inner lining plate 531. The other side of the glass sheet 1, near the patch 4, is inserted into the socket groove. The patch 4 rests against the bottom of the socket groove.

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

[0075] The pressing plate 53 has two opposite sides respectively provided with second through holes. The two limbs 511 are movably arranged in the second through holes of the pressing plate 53 .

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

[0077] A spring-loaded elastic pressure device applies pressure to the prefabricated patch, which extends beyond the edge of the glass, toward the notch in the sealing frame. The device is then secured to the side of the glass sheet, maintaining pressure on the patch until the vacuum glazing is complete. Pressure is applied from the time the solder softens, until it reaches the sealing temperature, and until the glass sheet is formed. This facilitates full wetting and sealing between the solder and the glass sheet surface, minimizing foaming. The elastic pressure device is fixed to the glass sheet and can be moved with it, allowing for unrestricted placement.

[0078] See Figure 5 As shown, when placing the elastic pressure device, a shielding plate 7 can be covered outside the area 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 , sequentially evacuating the two glass sheets 1 and sealing them for the second time, so that a vacuum is formed in the cavity, and the second solder melts to seal the gap 20 .

[0080] Glass sheets equipped with elastic pressure devices are fed into multiple consecutive vacuum chambers for low-temperature preheating and evacuation. Air within the glass sheets is extracted through exhaust channels within the gaps in the sealing frame. When the vacuum and temperature reach a certain level, they enter the second edge sealing chamber. The heating device in this sealing chamber locally heats the patching components and getter in the edge gaps, softening the patching components and gradually heating them to the sealing temperature. The elastic pressure device then gradually presses the solder into the gaps, fully filling them and completing the second edge sealing.

[0081] Before the gap is sealed, the gas in the glass is continuously discharged through the gradually shrinking gap, and the getter can also be activated at the same time.

[0082] Finally, it is gradually cooled and pressurized to atmospheric pressure, then taken out of the furnace and the elastic pressurizing device is removed to complete the production of vacuum glass.

[0083] In this embodiment, the glass sheet 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] See Figure 8 As shown, the heating device of the second edge sealing chamber is a plurality of infrared heating tubes 8 with a focusing reflective coating that are closely arranged and distributed on one side or both sides of the glass. Each infrared heating tube can be controlled individually and can automatically start the nearest one or more infrared heating tubes according to the notch of the sealing frame on the multiple glass plates on the carrier and the position of the getter.

[0086] The wavelength of the infrared light heating tube of the heating device of the first and second edge sealing chambers can be 900-1300nm. Infrared light in this wavelength range heats up quickly and reduces the degree of stress annealing on the glass surface.

[0087] In some embodiments, when the first solder is a metal solder at 250°C and the second edge sealing solder is a metal solder at a temperature of 230°C, due to the low solder temperature and the large difference in the expansion coefficients of metal and glass, a metal-glass sealing transition layer can be coated around one or two pieces of glass before solder coating. After tempering, the first solder is coated on the transition layer to enhance the sealing strength between the metal solder and the glass through the transition layer. When placing the pressurizing device, a high-temperature clamp can be applied to the edge of the area affected by the local heating tube at the same time. In addition to the notch and the getter, a shielding plate is covered on other glass areas that can be affected by the local heating tube to reduce the impact of local heating on the first edge sealing tape. The getter can also be activated after the production of the vacuum glass is completed.

[0088] The present invention provides a vacuum glass, which is prepared by adopting the above-mentioned vacuum glass preparation method.

[0089] The vacuum glass of the present invention seals most of the edges of the glass sheets at high temperature under atmospheric pressure and seals a small part of the edges (i.e., the gap) at low temperature under vacuum. The elastic pressurizing device is conducive to the removal 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 part under vacuum, and the placement and position of the getter, the second edge sealing only heats the glass sheet locally, greatly reducing the annealing effect on the overall tempered surface stress of the glass sheet.

[0091] Because the elastic pressure device is locked to the glass plate and can be placed without restrictions, production efficiency is greatly improved.

[0092] The vacuum glass preparation method of the present invention pre-seales the edges in the atmosphere, first closes the pieces and then heats them, so that the solder and the glass have enough time to fully infiltrate. When the soldering temperature is reached, the solder and the glass have the same temperature, which is beneficial to enhancing the sealing strength.

[0093] In the vacuum glass preparation method of the present invention, a getter is placed through the gap after the pre-sealed edge is cooled, thereby preventing the getter from being oxidized by high temperature in the atmosphere and improving the service life.

[0094] 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 glass annealing.

[0095] The vacuum glass preparation method of the present invention can seal and activate the getter only by one high-temperature heating, thereby alleviating edge stress annealing.

[0096] In the vacuum glass fabrication method of the present invention, the patching piece is in long-term, full contact and soaking with the glass under the action of an elastic pressure module. During sealing, the patching piece and the contact glass are at the same temperature, enhancing the sealing strength. The patching piece is constantly under the pressure of the pressure module from its softening temperature to the welding temperature and then to completion, preventing the solder from foaming.

[0097] In the vacuum glass preparation method of the present invention, the thickness of the gap of the sealing frame is greater than that of the support member and the presence of the pressurizing module enables the solder to form a sufficiently wide welding band, thereby enhancing the sealing performance.

[0098] The welding temperature of the patching piece in the vacuum glass manufacturing method of the present invention can be lower than that of the first solder, thereby reducing the influence of heating on the first solder.

[0099] The second local edge sealing in the vacuum glass preparation method of the present invention has a small heating area and little influence on the stress of the glass surface.

[0100] The vacuum glass preparation method of the present invention pre-seales the edges under atmosphere and effectively avoids the disadvantages of solder easily foaming and outgassing at high temperature under vacuum, thereby helping to improve the vacuum degree and welding strength.

[0101] The vacuum glass preparation method of the present invention adopts an elastic pressure device and a patch fixed on the glass, which can move arbitrarily with the glass. In addition, the heating tube in the vacuum sealing chamber automatically selects local heating. During production, the glass can be placed arbitrarily on the carrier according to the size of the glass. The equipment loading rate is high, the production efficiency of the vacuum production line is improved, and it is suitable for large-scale production.

[0102] In order to further illustrate the vacuum glass preparation method of the present invention in detail, the following examples are given for illustration.

[0103] S11 . Provide two glass sheets 1 , and grind the corner portion of one side of the back surface of the glass sheet 1 to form a notch 10 .

[0104] A notch is ground on one entire side of a glass plate. The width of the notch is 12 mm and the amount of grinding in the thickness direction is 1 mm.

[0105] S21. Temper the two glass plates 1 and apply the first solder low-melting-point glass powder 2 on the outer edge of the back side of the glass plate 1. The first solder 2 is arranged in a circle along the circumferential direction of the glass plate 1. A notch 20 is formed in the circle of the first solder 2. The notch 20 is arranged at the position of the notch 10.

[0106] After tempering, a first solder low-melting-point glass powder is applied to the edge and notch edge of one of the glass sheets. Since the weld seam on the notch edge is larger than that on other edges, the coating amount is 1 times that of other edges. The sealing temperature of the first solder is 430°C, and a 10mm gap is reserved in the first solder strip at a corner of the notch edge. The starting point is located on the inner side of the solder strip on the adjacent straight edge, and the starting point is 12mm away from the adjacent glass edge.

[0107] S31. Put the two glass plates 1 together so that the back surfaces of the two glass plates 1 face each other.

[0108] Two pieces of tempered glass with 0.2 mm high support members 4 and first solder 2 are joined together, and high-temperature clamps are arranged around them.

[0109] S41 , performing a first sealing on the two joined glass sheets 1 , so that the first solder 2 melts to form a sealing frame bonded between the back surfaces of the two glass sheets 1 .

[0110] After being sent into the continuous edge sealing furnace for preheating at 150℃, debinding at 350℃ and sealing at 430℃, the first sealing of the edge of the glass plate is completed. After cooling, the sealing tape at the corner of the notch forms a sealing frame gap formed by the sealing tapes on both sides and the two pieces of glass. The length is reduced to 6mm due to the melting of the sealing tapes on both sides, and the thickness direction is 1.2mm.

[0111] S51 , placing the getter 3 into the cavity between the two glass plates 1 through the notch 20 on the sealing frame.

[0112] A strip-shaped getter with a thickness of 0.15 mm and a width of 5 mm is inserted into the vacuum layer through the notch.

[0113] S61 , sintering a second solder low-melting-point glass powder to form a patching piece 4 and inserting the patching piece 4 into the notch 20 , with one end of the patching piece 4 facing the cavity.

[0114] A prefabricated, sintered second-type low-melting-point glass powder edge-sealing patch is placed into the notch at the edge of the cutout. The sealing temperature of the patch is 380°C. The length, width, and height of the sealing frame are slightly smaller than the notch, forming an exhaust passage connecting the inside and outside of the glass. The patch also protrudes above the edge of the glass sheet. Placement of the patch within the notch facilitates full contact between the heated and softened solder and the glass surface within the notch, creating an effective seal.

[0115] S71 , installing the elastic pressure device 5 on the two glass plates 1 , and elastically pressing the elastic pressure device 5 against the other end of the patch 4 .

[0116] Maintaining a certain pressure from the time the solder begins to soften to the time it reaches the sealing temperature to the time the vacuum glass is made is beneficial for the solder to fully infiltrate and seal the glass surface and avoid bubbling of the solder under vacuum.

[0117] S81 , sequentially evacuating and sealing the two glass plates 1 for a second time, so that a vacuum is formed in the cavity, and the second solder melts to seal the gap 20 .

[0118] Place the glass plate with an elastic pressure device on the support frame. When placing it, the direction of the notch getter is parallel to the direction of the heating tube in the sealing chamber behind it. In addition to the notch and the getter, other glass areas that can be affected by the local heating tube are covered with shielding plates to reduce the impact of local heating on the surface stress of other glass areas.

[0119] Then it is sent to multiple continuous vacuum chambers for low temperature preheating and vacuuming. The low temperature preheating and vacuuming are carried out in multiple vacuum chambers. The temperature and vacuum degree are gradually increased. When the vacuum degree reaches 10 -3 When the pa and temperature reach 280℃, it enters the sealing chamber. The infrared heaters in the sealing chamber are closely arranged. According to the edge gap of each piece of glass on the carrier and the position of the getter, it can automatically select a nearest heater for local heating, soften the patch and gradually heat it to the sealing temperature of 380℃. Under the action of the pressurizing tooling, the solder is gradually pressed in and fully fills the gap to complete the second edge sealing and form a vacuum layer. At the same time, the strip getter can also be activated.

[0120] Finally, it is gradually cooled and pressurized to atmospheric pressure, then taken out of the furnace and the pressurizing device is removed to complete the production of vacuum glass.

[0121] The above description is merely a preferred embodiment of the present application and an illustration of the technical principles employed. Those skilled in the art should understand that the scope of the invention herein is not limited to the technical solutions formed by the specific combination of the above-mentioned technical features, but also encompasses other technical solutions formed by any combination of the above-mentioned technical features or their equivalents without departing from the inventive concept. For example, a technical solution formed by replacing the above-mentioned features with (but not limited to) technical features having similar functions disclosed in this application.

Claims

1. A method for preparing vacuum glass, characterized in that: The following steps are involved: Two glass sheets are provided, each of which has a front surface and a back surface, and a corner portion of one side of the back surface of the glass sheet is ground to form a notch; The notch has an inner side facing the plane center of the glass sheet and an outer side facing away from the plane center, and the width of the notch gradually decreases from the outer side of the notch to the inner side of the notch; Tempering the two glass sheets and applying a first solder on the outer edges of the back sides of the glass sheets, wherein the first solder is arranged in a circle along the circumference of the glass sheets, and a notch is formed in the circle of the first solder, wherein the notch is arranged at the position of the notch; Putting the two glass sheets together so that the back surfaces of the two glass sheets face each other; Under normal pressure, the two glass sheets are sealed for the first time after being joined, so that the first solder melts to form a sealing frame bonded between the back surfaces of the two glass sheets; placing a getter into the cavity of the two glass sheets through the notch on the sealing frame; Sintering a second solder to form an insert and inserting the insert into the notch, with one end of the insert facing the cavity, wherein the sealing temperature of the second solder is lower than the sealing temperature 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 elastically presses against the other end of the patch; Evacuating the two glass sheets and performing a second sealing process under vacuum, so that a vacuum is formed in the cavity and the second solder melts to seal the gap; The elastic pressure device includes: a pressure rod, which presses against the side of the glass plate away from the patch, and the opposite ends of the pressure rod are bent to form two limbs, and the ends of the two limbs extend to the outside of the other side of the glass plate close to the patch; a reaction plate, which is adjustably mounted on the ends of the two limbs; a pressure plate, which is elastically mounted on one side of the reaction plate facing the other side of the glass plate, and the inner side of the pressure plate is connected to an inner lining plate, and a socket groove is formed on the inner lining plate, and the other side of the glass plate close to the patch is embedded in the socket groove, and the patch presses against the bottom of the socket groove.

2. The method for preparing vacuum glass according to claim 1, wherein: The back surfaces of the two glass plates are respectively formed with the notches.

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

4. The method for preparing vacuum glass according to claim 1, wherein: 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 accommodated in the limiting groove.

5. The method for preparing vacuum glass according to claim 1, wherein: A first through hole is respectively provided at the opposite ends of the reaction plate, and the ends of the two limbs can be 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 screw parts, and the screw parts are pressed against the other side of the reaction plate.

6. The method for preparing vacuum glass according to claim 5, wherein: The pressure plate is provided with second through holes on opposite sides thereof, and the two limbs are movably inserted into the second through holes of the pressure plate.

7. The method for preparing vacuum glass according to claim 1, wherein: During the first sealing and the second sealing, the wavelength of the infrared light heating tube of the heating device in the sealing chamber is 900 to 1300 nm.

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

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