Vacuum glass and preparation method thereof

Abstract

The invention discloses vacuum glass and a preparation method thereof. The preparation method comprises the following steps: grinding corners on one sides of the back surfaces of two glass sheets to form notches; tempering the two glass sheets, coating the outer edges of the back surfaces of the glass sheets with a first solder, and forming a notch; combining the two glass sheets; sealing the two glass sheets for the first time after the two glass sheets are combined; a getter is placed in the cavities of the two glass sheets through the notches in the sealing frame; sintering the second welding flux to form an inlaying piece and inserting the inlaying piece into the notch, wherein one end of the inlaying piece is arranged towards the cavity; elastic pressurizing devices are mounted on the two glass sheets, and the elastic pressurizing devices elastically abut against the other ends of the inlaying pieces; and sequentially carrying out vacuumizing and secondary sealing on the two glass sheets, so that vacuum is formed in the cavity, and the second welding flux is molten to seal the notch. The invention solves the problem that the solder at the vacuum lower edge part is easy to foam when being heated at high temperature in the existing vacuum glass preparation method.

Description

Technical Field

[0001] The 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 is two pieces of glass sealed on all sides and separated by a small support, with a vacuum state in the middle. Due to the existence of the vacuum layer, vacuum glass has excellent thermal insulation and sound insulation performance, and is very thin and light; at the same time, due to the good air tightness and sealing strength of the solder around it. Based on the above characteristics, vacuum glass is widely used in industries such as building energy-saving doors and windows, refrigerator energy-saving glass doors, etc.

[0003] The existing vacuum glass preparation method (such as the Chinese patent with announcement number CN104030557B) has reduced the impact of edge degassing on the vacuum degree, but still has not solved the problem of foaming of edge solder under vacuum under high temperature heating and two high temperature heating annealing. In addition, the sealing solder is placed outside the glass and cannot fully infiltrate the glass surface before reaching the sealing temperature, and it is difficult to press into the tiny vacuum layer to form an effective sealing width. After the sealing solder softens to a molten state, it is easy to foam without external force constraints. The sealing device is fixed on a mechanism outside the glass, and the glass placement position is limited, which is not conducive to continuous mass production.

[0004] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment 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 prior art, a vacuum glass and a preparation method thereof are provided to solve the problem that the solder at the bottom of the vacuum glass is easily foamed when heated at high temperature.

[0006] To achieve the above object, a method for preparing vacuum glass is provided, comprising: Providing two glass sheets, each of which has a front surface and a back surface, and grinding a corner portion of one side of the back surface of the glass sheet to form a notch; Tempering the two glass sheets and coating the outer edge of the back side of the glass sheets with a first solder, wherein the first solder is arranged in a circle along the circumferential direction of the glass sheets, and a notch is formed in the circle of the first solder, and the notch is arranged at the notch position; Putting the two glass sheets together so that the back surfaces of the two glass sheets are arranged opposite to each other; Under normal pressure, the two glass sheets after being joined are sealed for the first time, 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, the sealing temperature of the second solder being lower than the sealing temperature of the first solder and the temperature difference being lower 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 patching member; The two glass plates are evacuated and sealed for the second time in sequence, so that a vacuum is formed in the cavity and the second solder is melted to seal the gap.

[0007] 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.

[0008] Furthermore, the notches are respectively formed on the back sides of the two glass plates.

[0009] Furthermore, a solder transition layer is provided between the first solder and the back surface of the glass plate.

[0010] Furthermore, a limiting groove is formed on the back side of the glass plate, one end of the limiting groove is connected to the notch, and the getter is accommodated in the limiting groove.

[0011] Furthermore, the elastic pressure device comprises: A pressing rod is pressed against a side of the glass sheet away from the patching piece, and 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 patching piece; A reaction plate, which is adjustably mounted on the ends of the two limb rods; 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.

[0012] Furthermore, first through holes are respectively opened at the opposite ends of the reaction plate, and the ends of the two limbs can be movably inserted into the first through holes. External threads are formed at the ends of the limbs, and screw parts are screwed on the ends of the limbs, and the screw parts are pressed against the other side of the reaction plate.

[0013] 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.

[0014] 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 900-1300nm.

[0015] The present invention provides a vacuum glass which is prepared by adopting the above-mentioned vacuum glass preparation method.

[0016] The beneficial effect of the present invention is that, in the method for preparing vacuum glass of the present invention, the pre-sealing edge is first combined and then heated under the atmosphere, so that the solder and the glass are fully infiltrated for a sufficient time, and when the welding temperature is reached, the temperature of the contact surface of the solder and the glass is the same, which is conducive to enhancing the sealing strength. In the method for preparing vacuum glass of the present invention, after the pre-sealing edge is cooled, a getter is placed through the gap to avoid oxidation of the getter by the high temperature in the atmosphere, thereby improving the service life. In the method for preparing vacuum glass of the present invention, only one high-temperature heating is required to seal and activate the getter, thereby reducing the stress annealing of the edge. In the method for preparing vacuum glass of the present invention, the patch is in full contact and infiltration with the glass for a long time under the action of the elastic pressure module, and the temperature of the contact surface of the patch is the same as that of the glass during sealing to improve the sealing strength. The patch is always under the extrusion of the pressure module from the softening temperature to the welding temperature and then to the completion of the production, and the solder is not easy to foam. The second local edge sealing of the method for preparing vacuum glass of the present invention has a small heating area and a small effect on the stress of the glass surface. In the method for preparing vacuum glass of the present invention, the pre-sealing edge under the atmosphere effectively avoids the disadvantages of high-temperature foaming and degassing of the solder under vacuum, which helps to improve the vacuum degree and welding strength. The vacuum glass preparation method of the present invention adopts an elastic pressurizing device and a patching piece 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 mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Other features, objects and advantages of the present application will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings: Figures 1 to 7 Schematic diagram of the steps of a method for preparing vacuum glass according to an embodiment of the present invention.

[0018] Figure 8 Schematic diagram of the structure of the elastic pressure device according to an embodiment of the present invention.

[0019] Figures 9 to 11 Schematic diagrams of three forms of notches according to embodiments of the present invention.

[0020] Fig.12 Schematic diagram of the state of the getter in the limiting groove according to an embodiment of the present invention.

[0021] Fig.13 It is a schematic diagram of the state of the getter according to an embodiment of the present invention under the limitation of the strip ink.

[0022] Fig.14 Schematic diagram of the layout of the solder transition layer according to an embodiment of the present invention. DETAILED DESCRIPTION

[0023] The present application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant inventions, rather than to limit the inventions. It should also be noted that, for ease of description, only the parts related to the invention are shown in the accompanying drawings.

[0024] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present 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.

[0025] Reference Figures 1 to 14 As shown, the present invention provides a method for preparing vacuum glass, comprising the following steps: S1. See Figure 1 Two glass sheets 1 are provided, each of which has a front side and a back side, and a notch 10 is formed by grinding a corner portion of one side of the back side of the glass sheet 1 .

[0026] As a preferred embodiment, the notch is arranged along the length or width direction of the glass plate. The length of the notch is adapted to the length or width of the glass plate. When the thickness of the glass plate is thin, a notch with a smaller length is prone to stress concentration at the notch position after grinding, increasing the risk of damage to the glass plate.

[0027] 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 in FIG. 1 , the width of the notch 10 gradually decreases from the outer side of the notch 10 to the inner side of the notch 10. The grinding surface of the notch is an inclined surface (such as Figure 1 As shown), plane (as Fig. 9 As shown), curved surface (such as Fig.10 The concave arc surface shown in Fig.11 convex curved surface shown).

[0028] In some embodiments, notches 10 are formed on the back sides of the two glass plates 1 .

[0029] Specifically, a portion of one side of a glass plate or the same side of two glass plates is ground off to form a notch edge whose edge thickness is less than the middle thickness of the glass.

[0030] 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.

[0031] S2, tempering the two glass plates 1 and coating 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, and a notch 20 is formed in the circle of the first solder 2, and the notch 20 is arranged at the position of the notch 10.

[0032] Before the glass sheets are tempered, a support member 11 is arranged 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.

[0033] 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.

[0034] The width of the notch is 5 to 50 mm, and the distance between the starting point and the surface of the side of the adjacent glass plate is 0 to 60 mm.

[0035] As a preferred implementation, see Fig.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 a low melting point glass powder or a metal material.

[0036] Before solder coating, a solder transition layer can be coated around one or two glass sheets, and after the glass sheets are tempered, the first solder is coated on the solder transition layer to enhance the sealing strength between the first solder and the glass.

[0037] S3, putting the two glass plates 1 together so that the back surfaces of the two glass plates 1 are arranged opposite to each other.

[0038] The two pieces of tempered glass with the support and the first solder are put together, and high-temperature clamps are arranged around them.

[0039] S4. Under normal pressure, the two glass sheets 1 after being joined are sealed for the first time, so that the first solder 2 melts to form a sealing frame bonded between the back surfaces of the two glass sheets 1 .

[0040] Under normal pressure (i.e. atmospheric pressure), the assembled glass sheets are sent to 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 larger than the height of the support is formed in the sealing frame at the corner of the notch, and the first solder is coated on the other parts of the notch edge except the notch.

[0041] When sealing under normal pressure, solder is not prone to produce bubbles.

[0042] S5. Place the getter 3 into the cavity of the two glass plates 1 through the notch 20 on the sealing frame.

[0043] 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.

[0044] As a preferred implementation, see Fig.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. The getter is accommodated in the limiting groove.

[0045] The getter is put 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.

[0046] The limiting groove can be formed by grinding the inner side of the glass plate, or by forming two convex ridges 9 arranged opposite to each other on the inner side of the glass plate.

[0047] See also Fig.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.

[0048] Getters are either non-evaporable or evaporable, or both, and can also be activated after the vacuum glass is fabricated.

[0049] S6. Sinter the second solder to form a patch 4 and insert it into the notch 20, with one end of the patch 4 facing the cavity. The sealing temperature of the second solder is lower than the sealing temperature of the first solder 2 and the temperature difference is less than 150°C.

[0050] In this embodiment, the length of the notch side is less than or equal to the length of the side where it is located and greater than or equal to the solder frame notch, so that the notch is formed to accommodate the inlay and facilitate processing. The inlay is cylindrical, rectangular, spherical or wedge-shaped.

[0051] In this embodiment, the patch is wedge-shaped.

[0052] The second solder is prefabricated and sintered into a solid patch and 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 there is a gap 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 is conducive to the solder being heated and softened to fully contact the glass surface in the gap and form an effective sealing width.

[0053] The inlay may be one piece or multiple pieces.

[0054] 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 reduce the annealing of the local heated glass at the notch position of the sealing frame and the impact on the edge sealing of the first solder.

[0055] The first solder and the second solder are low melting point glass powder or metal solder.

[0056] S7, installing an elastic pressure device 5 on the two glass plates 1, and the elastic pressure device 5 elastically presses against the other end of the patching member 4.

[0057] In this embodiment, the elastic pressure device 5 includes a pressing rod 51 , a reaction plate 52 and a pressing plate 53 .

[0058] The pressing rod 51 abuts against one side of the glass sheet 1 away from the patch 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 sheet 1 close to the patch 4.

[0059] The reaction plate 52 is installed at the ends of the two limb rods 511 in an adjustable manner.

[0060] The pressure plate 53 is elastically mounted on one side of the reaction plate 52 facing the other side of the glass plate 1. The inner side of the pressure plate 53 is connected to an inner lining plate 531. A socket groove is formed on the inner lining plate 531. The other side of the glass plate 1 close to the patch 4 is embedded in the socket groove. The patch 4 abuts against the bottom of the socket groove.

[0061] The reaction plate 52 has first through holes at 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 screw parts 54. The screw parts 54 are pressed against the other side of the reaction plate 52.

[0062] Second through holes are respectively formed on opposite sides of the pressing plate 53. The two limbs 511 are movably inserted into the second through holes of the pressing plate 53.

[0063] The pressure plate 53 is elastically mounted on the reaction plate 52 via a spring 55 .

[0064] Use a spring-loaded elastic pressure device to apply pressure to the prefabricated patching piece that is higher than the edge of the glass toward the notch of the sealing frame, and fix the device to the side of the glass plate, and continue to apply pressure to the patching piece until the vacuum glass processing is completed. Apply pressure from the time when the solder begins to soften to the time when it reaches the sealing temperature to the time when the glass plate is completed, which is conducive to the full infiltration and sealing of the solder and the surface of the glass plate, and reduces foaming. The elastic pressure device is fixed on the glass plate and can move with the glass plate, and can be placed without restriction.

[0065] See also 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.

[0066] 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 .

[0067] The glass sheets with elastic pressure devices are sent into multiple continuous vacuum chambers for low-temperature preheating and vacuuming. The air in the glass sheets is extracted through the exhaust channel in the gap of the sealing frame. When the vacuum degree and temperature reach a certain level, they enter the second edge sealing chamber. The heating device in the sealing chamber can locally heat the patching parts and getter of the edge gap, soften the patching parts and gradually heat them to the sealing temperature. Under the action of the elastic pressure device, the solder is gradually pressed into and fully fills the gap, completing the second edge sealing.

[0068] 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.

[0069] 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.

[0070] In this embodiment, the glass sheet with the elastic pressure device can be fed into the vacuum chamber vertically or horizontally.

[0071] 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.

[0072] See also Figure 8 As shown, the heating device of the second edge sealing chamber is a plurality of infrared heating tubes 8 with focusing reflective coatings which 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.

[0073] The wavelength of the infrared light heating tube of the heating device of the first and second edge sealing chambers can be 900-1300nm. The infrared light heating in this wavelength band heats up quickly and reduces the stress annealing degree of the glass surface.

[0074] 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 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, and the first solder is coated on the transition layer after tempering. The sealing strength between the metal solder and the glass is enhanced by the transition layer, and 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 vacuum glass is produced.

[0075] The present invention provides a vacuum glass which is prepared by adopting the above-mentioned vacuum glass preparation method.

[0076] 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 gap) at low temperature under vacuum. The elastic pressurizing device is conducive to the removal of solder bubbles, which greatly reduces the possibility of bubbling during high-temperature welding under vacuum and basically avoids bubbling.

[0077] Because the second edge sealing only needs to seal a small part under vacuum, coupled with the placement and position of the getter, the second edge sealing only heats the glass plate locally, greatly reducing the annealing effect on the overall tempered surface stress of the glass plate.

[0078] Because the elastic pressure device is locked to the glass plate and can be placed without restriction, the production efficiency is greatly improved.

[0079] The vacuum glass preparation method of the present invention is to pre-seal the edges in the atmosphere, first close the sheets and then heat them, so that the solder and the glass have enough time to fully infiltrate. When the welding temperature is reached, the temperatures of the solder and the glass are the same, which is beneficial to enhancing the sealing strength.

[0080] The vacuum glass preparation method of the present invention provides a method for placing a getter 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.

[0081] 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.

[0082] The vacuum glass preparation method of the present invention can seal and activate the getter only by high-temperature heating once, thereby alleviating edge stress annealing.

[0083] In the vacuum glass preparation method of the present invention, the patch is in full contact and infiltration with the glass for a long time under the action of the elastic pressure module, and the patch is at the same temperature as the contact glass during sealing to improve the sealing strength. The patch is always under the extrusion of the pressure module from the softening temperature to the welding temperature and then to the completion of the production, and the solder is not easy to foam.

[0084] In the method for preparing vacuum glass 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, so that the solder forms a sufficiently wide welding band to enhance the sealing performance.

[0085] The welding temperature of the inlay 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.

[0086] 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.

[0087] The vacuum glass preparation method of the present invention pre-seales the edges under the atmosphere to effectively avoid the disadvantages of solder foaming and degassing at high temperature under vacuum, and is helpful to improve the vacuum degree and welding strength.

[0088] The vacuum glass preparation method of the present invention adopts an elastic pressurizing device and a patching piece 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 mass production.

[0089] In order to further illustrate the method for preparing vacuum glass of the present invention in detail, the following examples are given for illustration.

[0090] S11, providing two glass sheets 1, and grinding the corner portion of one side of the back side of the glass sheet 1 to form a notch 10.

[0091] A notch is ground on one entire side of a glass plate, the width of the notch is 12 mm, and the grinding amount in the thickness direction is 1 mm.

[0092] S21, tempering two glass plates 1 and coating 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, and a notch 20 is formed in the circle of the first solder 2, and the notch 20 is arranged at the position of the notch 10.

[0093] After tempering, the first solder low-melting point glass powder is coated on the edge and notch edge of one of the glass plates. Since the weld seam on the notch edge is larger than that on other edges, the coating amount is 1 times that on other edges. The sealing temperature of the first solder is 430°C, and a gap of 10 mm in length is reserved on 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 12 mm away from the adjacent glass edge.

[0094] S31, putting two glass plates 1 together so that the back surfaces of the two glass plates 1 are arranged opposite to each other.

[0095] Two pieces of tempered glass with 0.2 mm high support members 4 and first solder 2 are put together, and high temperature clamps are arranged around them.

[0096] 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 .

[0097] 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 edge of the notch forms a sealing frame gap formed by the sealing tapes on both sides and two pieces of glass. The length is reduced to 6mm due to the melting and widening of the sealing tapes on both sides, and the thickness direction is 1.2mm.

[0098] S51 , placing the getter 3 into the cavity of the two glass plates 1 through the notch 20 on the sealing frame.

[0099] 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.

[0100] S61, sintering the second solder low melting point glass powder to form the patch 4 and inserting it into the notch 20, with one end of the patch 4 facing the cavity.

[0101] The prefabricated second low-melting-point glass powder edge sealing patch that has been sintered into a patch is filled into the gap at the edge of the notch, and the sealing temperature of the patch is 380°C. The length, width and height of the sealing frame are slightly smaller than the gap of the sealing frame to form an exhaust channel connecting the inside and outside of the glass, and the patch is higher than the edge of the glass plate. Putting the patch into the gap is conducive to the solder being heated and softened to fully contact the glass surface in the gap and form an effective sealing width.

[0102] S71 , installing an elastic pressure device 5 on the two glass plates 1 , and the elastic pressure device 5 elastically presses against the other end of the patching member 4 .

[0103] A certain pressure is maintained from the time when the solder begins to soften to the time when the sealing temperature is reached to the time when the vacuum glass is made, which is conducive to the full wetting and sealing of the solder and the glass surface and to avoid bubbling of the solder under vacuum.

[0104] S81 , 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 .

[0105] Place the glass plate with an elastic pressure device on the support frame with the direction of the notch getter parallel to the direction of the heating tube in the sealing chamber behind. 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.

[0106] 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 pa and the 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 pressurized tooling, the solder is gradually pressed into 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.

[0107] 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.

[0108] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the above features are replaced with (but not limited to) technical features with similar functions disclosed in the present application.

Claims

1. A method for preparing vacuum glass, characterized in that: The following steps are involved: Providing two glass sheets, each of which has a front surface and a back surface, and grinding a corner portion of one side of the back surface of the glass sheet to form a notch; Tempering the two glass sheets and coating the outer edge of the back side of the glass sheets with a first solder, wherein the first solder is arranged in a circle along the circumferential direction of the glass sheets, and a notch is formed in the circle of the first solder, and the notch is arranged at the notch position; Putting the two glass sheets together so that the back surfaces of the two glass sheets are arranged opposite to each other; Under normal pressure, the two glass sheets after being joined are sealed for the first time, 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, the sealing temperature of the second solder being lower than the sealing temperature of the first solder and the temperature difference being lower 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 patching member; The two glass plates are evacuated and sealed for the second time under vacuum, so that a vacuum is formed in the cavity and the second solder is melted to close the gap.

2. The method for preparing vacuum glass according to claim 1, characterized in that: 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.

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

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

5. 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 the limiting groove is connected to the notch, and the getter is accommodated in the limiting groove.

6. The method for preparing vacuum glass according to claim 1, characterized in that: The elastic pressure device comprises: A pressing rod is pressed against a side of the glass sheet away from the patching piece, and 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 patching piece; A reaction plate, which is adjustably mounted on the ends of the two limb rods; 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.

7. The method for preparing vacuum glass according to claim 6, characterized in that: The reaction plate is provided with first through holes at opposite ends thereof, the ends of the two limbs are movably inserted into the first through holes, external threads are formed at the ends of the limbs, and screw parts are screwed on the ends of the limbs, and the screw parts are pressed against the other side of the reaction plate.

8. The method for preparing vacuum glass according to claim 7, characterized in that: The pressing plate is provided with second through holes at two opposite sides thereof, and the two limbs are movably inserted into the second through holes of the pressing plate.

9. The method for preparing vacuum glass according to claim 1, characterized in that: 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 900-1300nm.

10. A vacuum glass, characterized in that: The vacuum glass is prepared by the vacuum glass preparation method as described in any one of claims 1 to 9.

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