A vacuum extraction welding device for a pressure vessel and a vacuum extraction welding method for a pressure vessel

Abstract

The present invention discloses a vacuum pumping and welding device for a pressure vessel and a vacuum pumping and welding method for a pressure vessel. The vacuum pumping and welding device for a pressure vessel includes a frame, a placement chamber provided on the frame and having a placement cavity, a pressure vessel fixture provided in the placement cavity, a vacuum pumping mechanism communicated with the placement cavity, and a laser welding machine provided on the frame for hermetically welding the pressure vessel. The pressure vessel fixture includes a lower claw disc provided in the placement cavity, a first driving motor for driving the lower claw disc to rotate, an upper claw disc rotatably provided along its own axis direction in the placement cavity and located above the lower claw disc, and a driving assembly for driving the upper claw disc to move towards or away from the lower claw disc. The vacuum pumping and welding device for a pressure vessel of the present invention has a simple structure, a simple process and low cost for vacuum pumping and welding the pressure vessel, and a good hermetic welding effect. The vacuum pumping and welding method for a pressure vessel has simple steps for vacuum pumping and welding the pressure vessel and a good hermetic welding effect.

Description

Technical Field

[0001] The present invention relates to the field of vacuum pumping and welding of pressure vessels, and particularly to a vacuum pumping and welding device for pressure vessels and a vacuum pumping and welding method for pressure vessels. Background Art

[0002] Currently, the vacuum sealing process methods for metal pressure vessels in the market are mainly divided into three types: with-tail sealing and without-tail sealing.

[0003] With-tail sealing means that there is a tail chamber at the bottom of the pressure vessel after vacuum pumping, and there is a small tail inside the chamber. The process is to weld a copper tube on the hole where the air is pumped out of the pressure vessel (the welding has good sealing performance), and the size of the copper tube is the same as the aperture of the hole. The air between the inner and outer tubes of the pressure vessel is pumped out through the copper tube. After pumping to a vacuum, the copper tube is cut off, and the deformation of the copper tube during cutting is used to achieve the sealing state. The with-tail vacuum uses the "pressure sealing technology", and its sealing effect is not very ideal. The end of the copper tube of some products will be damaged after long-term use or being knocked, and the vacuum environment is damaged, resulting in the loss of the heat preservation effect of the pressure vessel.

[0004] The without-tail vacuum uses the "fusion sealing technology". A very small glass is placed beside the hole for pumping air at the bottom of the pressure vessel. The pressure vessel is placed in a sealed environment, and the sealed environment is pumped into a vacuum. During the vacuum pumping process, this space is heated. When the vacuum reaches a certain value, the heating temperature also reaches the melting value of the glass, and the hole at the bottom of the pressure vessel is sealed by the melting of the glass, so as to achieve the internal vacuum degree of the pressure vessel. This process makes no copper tube like the with-tail left at the bottom of the pressure vessel. However, the processing cost of the without-tail vacuum sealing method is relatively high, and if the pressure vessel is dropped or knocked during use, it is very easy for the sealed glass to be broken, thus destroying the vacuum environment and causing the pressure vessel to lose the heat preservation effect. Summary of the Invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art, and provide a vacuum pumping and welding device for pressure vessels, which has a simple structure, a simple process and low cost for vacuum pumping and welding of pressure vessels, and a good sealing and welding effect.

[0006] To achieve the above object, the technical solution adopted by the present invention is: a vacuum pumping and welding device for a pressure vessel, comprising a frame, a placement chamber provided on the frame and having a placement cavity, a pressure vessel fixture provided in the placement cavity, a vacuum pumping mechanism communicated with the placement cavity, and a laser welding machine provided on the frame for hermetically welding the pressure vessel. The placement chamber includes a chamber body having the placement cavity, the placement cavity has an opening communicated with the outside, the placement chamber further includes a chamber door matched with the opening, and a sealing driving mechanism for hermetically pressing the chamber door at the opening; the pressure vessel fixture includes a lower claw plate provided in the placement cavity, a first driving motor for driving the lower claw plate to rotate, an upper claw plate rotatably provided along its own axis direction and located above the lower claw plate in the placement cavity, and a driving component for driving the upper claw plate to move in a direction close to or away from the lower claw plate. The first driving motor and the driving component are both hermetically arranged with the placement cavity.

[0007] Preferably, the driving component includes a lead screw arranged in the vertical direction, a second driving motor for driving the lead screw to rotate, a roller matched with the lead screw, a guide post arranged in the placement cavity and parallel to the lead screw, and a sliding plate slidably sleeved on the guide post. The roller is fixed to the sliding plate, and the upper claw plate is rotatably arranged on the sliding plate along its own axis direction.

[0008] Preferably, the placement chamber further includes a slide rail provided at the opening, a chute matched with the slide rail is opened on the chamber door, and the sealing driving mechanism includes a first driving cylinder for driving the chamber door to reciprocate along the slide rail.

[0009] Further, the chamber door includes a front end cover provided with the chute, and a sealing cover slidably arranged on the front end cover and capable of moving in a direction close to or away from the opening. The sealing driving mechanism further includes a second driving cylinder for driving the sealing cover to move in a direction close to or away from the opening.

[0010] Furthermore, the chamber door further includes a guiding mechanism for guiding the movement of the sealing cover. The guiding mechanism includes a guiding hole provided on the front end cover and a guiding post fixed to the sealing cover and matched with the guiding hole.

[0011] Preferably, the vacuum pumping mechanism includes a low vacuum acquisition module communicated with the placement cavity and a high vacuum acquisition module communicated with the placement cavity.

[0012] Further, the low vacuum acquisition module includes a gas delivery vacuum pump, and the high vacuum acquisition module includes a gas capture vacuum pump.

[0013] Preferably, the vacuum welding device further includes a laser welding machine adjusting mechanism disposed on the frame. The laser welding machine is fixed to the laser welding machine adjusting mechanism, and the laser welding machine adjusting mechanism includes a lateral adjusting portion, a longitudinal adjusting portion, and a vertical adjusting portion.

[0014] Further, the laser welding machine includes a laser head. A laser head insertion hole is formed in the side wall of the cabin body. The laser head extends into the placement cavity through the laser head insertion hole. The laser head is connected to the laser head insertion hole by a flexible welding bellows, and a sealing lens is provided in the laser head.

[0015] Another object of the present invention is to provide a method for vacuum welding a pressure vessel, which has simple vacuum welding steps and good sealing welding effect.

[0016] To achieve the above object, the technical solution adopted by the present invention is: a method for vacuum welding a pressure vessel, characterized in that: it includes the above-mentioned pressure vessel vacuum welding device and the pressure vessel to be welded. The pressure vessel includes a pressure vessel body and a pressure vessel bottom. The pressure vessel body includes an outer tire and an inner tire connected to each other at one end. There is an open sandwich between the outer tire and the inner tire. The end of the pressure vessel bottom cooperates with the other end of the outer tire to form an annular weld gap. The method for vacuum welding a pressure vessel is as follows:

[0017] Step 1: Open the cabin door, clamp the pressure vessel body on the lower jaw plate, and clamp the pressure vessel bottom on the upper jaw plate;

[0018] Step 2: Drive the sealing drive mechanism to drive the cabin door to seal the placement cavity;

[0019] Step 3: Drive the low vacuum acquisition module to perform low vacuum pumping on the placement cavity;

[0020] Step 4: Drive the high vacuum acquisition module to perform high vacuum pumping on the placement cavity;

[0021] Step 5: Drive the drive assembly to drive the upper jaw plate to descend, so that the pressure vessel bottom is pressed against the pressure vessel body, so that the end of the pressure vessel bottom cooperates with the other end of the outer tire to form an annular weld gap 73

[0022] Step 6: Adjust the laser welding machine adjusting mechanism so that the light outlet of the laser welding machine directly faces the weld gap;

[0023] Step 7: Drive the first drive motor to drive the lower jaw plate to rotate, and drive the pressure vessel body and the bottom of the container to rotate synchronously. Drive the laser welding machine to weld the seam to be welded, so as to form a vacuum sealing interlayer between the outer tire, the inner tire and the bottom of the pressure vessel.

[0024] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art: The pressure vessel vacuum pumping and welding device and the pressure vessel vacuum pumping and welding method of the present invention can directly pump vacuum on the pressure vessel body and the bottom of the pressure vessel in the placement cavity, and directly weld the pressure vessel body and the bottom of the pressure vessel. The pressure vessel vacuum pumping and welding device has a simple structure, a simple process, low cost, good sealing welding effect and high stability for pumping vacuum and welding the pressure vessel. The pressure vessel vacuum pumping and welding method has a simple pumping vacuum and welding step, good sealing welding effect, high weld stability and is not easy to be damaged. It eliminates the cumbersome steps of first opening a seam at the bottom of the pressure vessel, then welding the pressure vessel body and the bottom of the pressure vessel, then pumping vacuum inside the pressure vessel, and finally welding the seam opened at the bottom of the pressure vessel. Brief Description of the Drawings

[0025] Att Figure 1 is a three-dimensional schematic diagram of the present invention;

[0026] Att Figure 2 is a three-dimensional structural schematic diagram of the present invention after removing the frame;

[0027] Att Figure 3 is the attached Figure 2 partial enlarged view of part A in the attached;

[0028] Att Figure 4 is a structural schematic diagram of the placement cabin, the pressure vessel fixture and the vacuum pumping mechanism of the present invention;

[0029] Att Figure 5 is a structural schematic diagram of the perspective view of the placement cabin, the pressure vessel fixture and the vacuum pumping mechanism of the present invention;

[0030] Att Figure 6 is the first structural schematic diagram of the pressure vessel;

[0031] Att Figure 7 is the attached Figure 6 partial enlarged view of part B in the attached;

[0032] Att Figure 8 is the second structural schematic diagram of the pressure vessel;

[0033] Att Figure 9 is the attached Figure 8 partial enlarged view of part C in the attached;

[0034] Appendix Figure 10 It is the third structural schematic diagram of the pressure vessel;

[0035] Appendix Figure 11 It is the appendix Figure 10 The partial enlarged view of part D in

[0036] Wherein: 1. Frame; 2. Placement cabin; 21. Placement cavity; 211. Opening; 22. Cabin body; 221. Laser head insertion hole; 23. Cabin door; 231. Front end cover; 232. Sealing cover; 233. Guiding mechanism; 2331. Guiding hole; 2332. Guiding column; 24. Sealing driving mechanism; 241. First driving cylinder; 242. Second driving cylinder; 25. Slide rail; 3. Pressure vessel fixture; 31. Lower claw disc; 32. First driving motor; 33. Upper claw disc; 34. Driving assembly; 341. Lead screw; 342. Second driving motor; 343. Guiding column; 344. Slide plate; 4. Vacuum pumping mechanism; 41. Low vacuum acquisition module; 42. High vacuum acquisition module; 5. Laser welding machine; 51. Laser head; 6. Laser welding machine adjustment mechanism; 61. Horizontal adjustment part; 62. Longitudinal adjustment part; 63. Vertical adjustment part; 7. Pressure vessel; 71. Pressure vessel body; 711. Outer tire; 712. Inner tire; 713. Interlayer; 72. Bottom of the pressure vessel; 73. Welding seam to be welded; 74. Limit protrusion. Specific embodiments

[0037] The technical solution of the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0038] Refer to Appendix Figure 1 to Appendix Figure 5 As shown, a pressure vessel vacuum pumping and welding device includes a frame 1, a placement cabin 2 provided on the frame 1 and having a placement cavity 21, a pressure vessel fixture 3 provided in the placement cavity 21, a vacuum pumping mechanism 4 communicated with the placement cavity 21, and a laser welding machine 5 provided on the frame 1 for hermetically welding the pressure vessel 7.

[0039] The placement cabin 2 includes a cabin body 22 having a placement cavity 21. The placement cavity 21 has an opening 211 communicated with the outside. The opening 211 of the placement cavity 21 is located on the side, top or bottom of the cabin body 22. The placement cabin 2 further includes a cabin door 23 matching the cavity opening 211 and a sealing driving mechanism 24 for hermetically pressing the cabin door 23 at the opening 211.

[0040] A slide rail 25 is provided at the opening 211 of the placement cavity. A chute matching the slide rail 25 is opened on the hatch door 23. The sealing drive mechanism 24 includes a first drive cylinder 241 for driving the hatch door 23 to reciprocate along the slide rail 25. The cylinder block of the first drive cylinder 241 is fixed to the frame 1, and the piston rod is fixed to the hatch door 23. The movement of the hatch door 23 to or away from the opening 211 can be controlled by the first drive cylinder 241.

[0041] Preferably, the hatch door 23 includes a front end cover 231 with a chute, and a sealing cover 232 slidably arranged on the front end cover 231 and capable of moving towards or away from the opening 211. The sealing drive mechanism 24 further includes a second drive cylinder 242 for driving the sealing cover 232 to move towards or away from the opening 211 of the placement cavity. Preferably, the cylinder block of the second drive cylinder 242 is fixed to the front end cover 231, and the piston rod is fixed to the sealing cover 232. After the first drive cylinder 241 controls the hatch door 23 to move to the opening 211 of the placement cavity, the second drive cylinder 242 drives the sealing cover 232 to move towards the opening 211 of the placement cavity, so that the sealing cover 232 is pressed against the opening 211 of the placement cavity to achieve a sealing effect. To enhance the sealing effect, a sealing ring is provided around the opening 211 of the placement cavity.

[0042] The hatch door 23 further includes a guiding mechanism 233 for guiding the movement of the sealing cover 232, so that the sealing cover 232 can reciprocate stably. The guiding mechanism 233 includes a guiding hole 2331 provided on the front end cover 231 and a guiding post 2332 fixed to the sealing cover 232 and matching the guiding hole 2331. Preferably, a plurality of guiding mechanisms 233 are provided, and the plurality of guiding mechanisms 233 are arranged around the front end cover 231, and the second drive cylinder 242 is arranged in the middle of the plurality of guiding mechanisms 234. The guiding mechanism 233 exemplified in this embodiment is an example, and any guiding mechanism 233 that can guide the movement of the sealing cover 232 is within the protection scope of this application.

[0043] The pressure vessel fixture 3 includes a lower jaw plate 31 arranged in the placement cavity 21, a first drive motor 32 for driving the lower jaw plate 31 to rotate, an upper jaw plate 33 rotatably arranged along its own axis direction in the placement cavity 21 and located above the lower jaw plate 31, a drive assembly 34 for driving the upper jaw plate 33 to move towards or away from the lower jaw plate 31, a lower jaw plate drive mechanism for driving the lower jaw plate 31 to clamp or loosen, and an upper jaw plate drive mechanism for driving the upper jaw plate 33 to clamp or loosen. The first drive motor 32 and the drive assembly 34 are both hermetically arranged with the placement cavity 21.

[0044] In this embodiment, the driving component 34 includes a lead screw 341 arranged in the vertical direction, a second driving motor 342 for driving the lead screw 341 to rotate, a roller engaged with the lead screw 341, a plurality of limiting columns 343 arranged in parallel with the lead screw 341 in the placement cavity 21, and a sliding plate 344 sleeved on the plurality of limiting columns 343. The sliding plate 344 is fixed to the roller. The upper claw plate 33 is rotatably arranged on the sliding plate 344 along its own axial direction. The second driving motor 342 drives the lead screw 341 to rotate, thereby driving the upper claw plate 33 to move up and down.

[0045] The vacuum pumping mechanism 4 in this embodiment includes a low-vacuum acquisition module 41 communicated with the placement cavity 21 and a high-vacuum acquisition module 42 communicated with the placement cavity 21. Preferably, the low-vacuum acquisition module 41 includes a gas transfer vacuum pump. The gas transfer vacuum pump includes a variable-volume vacuum pump, a momentum transfer pump, etc. Among them, the variable-volume vacuum pump includes a reciprocating vacuum pump, a rotary vacuum pump, etc.; the high-vacuum acquisition module 42 includes a gas capture vacuum pump. The gas capture vacuum pump includes an adsorption pump, a getter pump, a cryopump, etc. Preferably, the low-vacuum acquisition module is communicated with the rear side of the placement cavity 21. To increase the acquisition time and acquisition effect of the low vacuum in the placement cavity 21, 4 identical low-vacuum acquisition modules are provided in this embodiment. Preferably, the high-vacuum acquisition module is communicated with the top of the placement cavity 21. Throttle valves are provided on the pipelines where the low-vacuum acquisition module 41 and the high-vacuum acquisition module 42 are communicated with the placement cavity 21.

[0046] After sealing the placement cavity 21, the variable-volume vacuum pump first performs rough vacuum pumping on the placement cavity 21 to make the vacuum degree in the placement cavity 21 reach 10 - 100 Pa, and then a cryopump or a molecular vacuum pump intervenes to perform fine vacuum pumping on the placement cavity 21. Taking the cryopump as an example in this embodiment, a cold plate cooled to an extremely low temperature by liquid helium or a refrigerator is provided in the cryopump. The cryopump condenses the gas in the placement cavity 21 and keeps the vapor pressure of the condensate lower than the ultimate pressure of the pump, thereby achieving the effect of high vacuum pumping. This enables the interior of the placement cavity 21 to reach a high-vacuum state, without gas molecule interference, resulting in a high vacuum degree and good heat preservation effect in the pressure vessel; at the same time, in the absence of gas molecule interference, it can reduce the interference with subsequent laser welding and increase the sealing effect of the welding.

[0047] The main functions of cryopumping are cryogenic condensation, cryogenic adsorption, and cryogenic trapping. ① Cryogenic condensation: Gas molecules condense on the surface of the cold plate or on the already condensed gas layer, and its equilibrium pressure is basically equal to the vapor pressure of the condensate. When pumping air, the temperature of the cold plate must be lower than 25 K; when pumping hydrogen, the temperature of the cold plate is even lower. The thickness of the cryogenic condensation pumping condensate layer can reach about 10 millimeters. ② Cryogenic adsorption: Gas molecules form a monolayer thickness (10 - 8The ones on the order of centimeters are adsorbed onto the surface of the adsorbent coated on the cold plate. The equilibrium pressure of adsorption is much lower than the vapor pressure at the same temperature. For example, at 20K, the vapor pressure of hydrogen is equal to the atmospheric pressure, while when hydrogen is adsorbed by activated carbon at 20K, the equilibrium pressure of adsorption is lower than 10- 8 Pa. Thus, it is possible to pump gas through cryo-adsorption at a relatively high temperature. ③ Cryo-trapping: Gas molecules that cannot be condensed at the pumping temperature are buried and adsorbed by the growing layer of condensable gas. Generally speaking, the ultimate pressure of the pump is the vapor pressure of the condensable gas at the temperature of the cold plate. At 120K, the vapor pressure of water is already lower than 10- 8 Pa. At 20K, the vapor pressures of other gases except helium, neon, and hydrogen are also lower than 10- 8 Pa. However, due to the temperature difference between the container to be pumped and the cryogenic cold plate, the ultimate pressure of the pump is higher than the vapor pressure of the condensate. For a container at room temperature and a cryogenic plate at 20K, the ultimate pressure of the pump is about 4 times the vapor pressure of the condensate. Finally, the vacuum degree in the placement cavity 21 is pumped to the vacuum degree required by the pressure vessel by the cryopump.

[0048] The vacuum pumping and welding device further includes a laser welding machine adjusting mechanism 6 provided on the frame 1, and the laser welding machine 5 is fixed on the laser welding machine adjusting mechanism 6. The laser welding machine adjusting mechanism 6 includes a lateral adjusting part 61, a longitudinal adjusting part 62, and a vertical adjusting part 63, which can adjust the laser welding machine 5 in the horizontal and vertical directions so that the laser beam of the laser welding machine 5 can directly irradiate the welding positions of the pressure vessel body 91 and the bottom 92. This laser welding machine adjusting mechanism 6 tends to finely adjust the position of the laser welding machine 5.

[0049] The laser welding machine 5 includes a laser head 51. A laser head insertion hole 221 is provided on the side wall of the cabin body 22. The laser head 51 extends into the placement cavity 21 through the laser head insertion hole 221. The laser head 51 is connected to the laser head insertion hole 221 in a soft seal manner. Preferably, a flexible welding bellows is used. The flexible welding bellows can not only move along with the laser head 51 but also ensure the sealing performance, so as to facilitate the adjustment of the position of the laser head 51; a sealing lens is provided in the laser head 51 to form a sealing effect between the laser head 51 and the placement cavity 21.

[0050] The pressure vessel 7 of this embodiment includes a pressure vessel body 71 and a pressure vessel bottom 72. The pressure vessel body 71 includes an outer tire 711 and an inner tire 712 connected to each other at one end. There is an open sandwich layer 713 between the outer tire 711 and the inner tire 712. The end of the pressure vessel bottom 72 cooperates with the other end of the outer tire 711 to form an annular weld gap 73. The pressure vessel vacuum welding device of this application welds the weld gap 73, so that a vacuum-sealed sandwich layer is formed between the outer tire 711, the inner tire 712, and the pressure vessel bottom 72. Preferably, the pressure vessel 7 is a metal product, and can be a thermos cup, a thermos flask, etc.

[0051] There are various cooperation methods between the end of the pressure vessel bottom 72 and the other end of the outer tire 711, all of which are within the protection scope of this application. For example, ① As shown in the attached Figure 6 and the attached Figure 7 , the end of the pressure vessel bottom 72 is located inside the other end of the outer tire 711. A limiting protrusion 74 is provided on the outer periphery of the end of the pressure vessel bottom 72 and / or a limiting protrusion 74 is provided on the inner periphery of the outer tire 911. An annular weld gap is formed between the outer tire 911 and the limiting protrusion 74; ② As shown in the attached Figure 8 and the attached Figure 9 , the end of the pressure vessel bottom 72 is located outside the other end of the outer tire 711. A limiting protrusion 74 is provided on the inner periphery of the end of the pressure vessel bottom 72 and / or a limiting protrusion 74 is provided on the outer periphery of the outer tire 911. An annular weld gap is formed between the end of the pressure vessel bottom 72 and the limiting protrusion 74; ③ As shown in the attached Figure 10 and the attached Figure 11 , preferably, the structure in which the end of the pressure vessel bottom 72 is located inside the other end of the outer tire 711 and a limiting protrusion 74 is provided on the outer periphery of the end of the pressure vessel bottom 72 is adopted. However, the above-mentioned 3 structures are all within the protection scope of this application.

[0052] A pressure vessel vacuum welding method includes the pressure vessel vacuum welding device and the pressure vessel 7 to be welded as described above. The pressure vessel 7 includes a pressure vessel body 71 and a pressure vessel bottom 72. The pressure vessel body 71 includes an outer tire 711 and an inner tire 712 connected to each other at one end. There is an open sandwich layer 713 between the outer tire 711 and the inner tire 712. The end of the pressure vessel bottom 72 cooperates with the other end of the outer tire to form an annular weld gap 73. The pressure vessel vacuum welding device of this application welds the weld gap 73, so that a vacuum-sealed sandwich layer is formed between the outer tire 711, the inner tire 712, and the pressure vessel bottom 72. Preferably, the pressure vessel 7 is a metal product, and can be a thermos cup, a thermos flask, etc.

[0053] The attached Figure 6 , the attached Figure 7 , the attached Figure 8 , the attached Figure 9 , the attachedFigure 10 and the attached Figure 11 The to-be-welded gap 73 shown in exaggerated form is larger than the actual to-be-welded gap 73. The actual situation is as follows: during the production process, as shown in the attached Figure 6 and the attached Figure 7 As shown, the outer tire 711 abuts against the limiting protrusion 74, and a very small to-be-welded gap 73 is formed between the outer tire 711 and the limiting protrusion 74, and a laser welding machine welds it; as shown in the attached Figure 8 and the attached Figure 8 As shown, the bottom 72 of the pressure vessel abuts against the limiting protrusion 74, and a very small to-be-welded gap 73 is formed between the bottom 72 of the pressure vessel and the limiting protrusion 74, and a laser welding machine welds it; as shown in the attached Figure 10 and the attached Figure 11 As shown, the bottom 72 of the pressure vessel abuts against the outer tire 711, and a very small to-be-welded gap 73 is formed between the bottom 72 of the pressure vessel and the outer tire 711, and a laser welding machine welds it. Because the to-be-welded gap 73 is very small, the completed weld seam is also small, which can save welding time and improve welding quality. (Compared with laser welding of large gaps, it wastes time, the welding sealing requirements are relatively high, and air-permeable small holes are likely to appear). The method for vacuum welding of the pressure vessel in this application is as follows:

[0054] Step 1: Open the hatch 23, clamp the pressure vessel body 71 on the lower jaw plate 31, and clamp the bottom 72 of the pressure vessel on the upper jaw plate 33;

[0055] Step 2: Drive the sealing drive mechanism 24 to drive the hatch 23 to seal the placement cavity 21;

[0056] Step 3: Drive the low-vacuum acquisition module 41 to perform low vacuum pumping on the placement cavity 21 to make the vacuum degree in the placement cavity 21 reach 10 - 100 Pa;

[0057] Step 4: Drive the high-vacuum acquisition module 42 to perform high vacuum pumping on the placement cavity 21 to condense the gas in the placement cavity 21 and keep the vapor pressure of the condensate lower than the ultimate pressure of the high-vacuum acquisition module 42, so as to achieve the effect of high vacuum pumping. Make the inside of the placement cavity 21 reach a high vacuum state without gas molecule interference;

[0058] Step 5: Drive the drive assembly 34 to drive the upper jaw plate 33 to descend, so that the bottom 72 of the pressure vessel is pressed against the pressure vessel body 71, so that the end of the bottom 72 of the pressure vessel cooperates with the other end of the outer tire 711 to form an annular to-be-welded gap 73;

[0059] Step 6: Adjust the laser welding machine adjustment mechanism 6 so that the light outlet of the laser welding machine 5 directly faces the to-be-welded gap 73;

[0060] Step 7: Drive the first driving motor 32 to drive the lower jaw plate 31 to rotate, and drive the pressure vessel body 71 and the vessel bottom 72 to rotate synchronously, and drive the laser welding machine 5 to weld the weld seam 73 to be welded, so as to form a vacuum sealing interlayer between the outer tire 711, the inner tire 712 and the pressure vessel bottom 72.

[0061] Take 20 thermos cups made by the above-mentioned pressure vessel vacuum pumping and welding device and the pressure vessel vacuum pumping and welding method for heat preservation experiments to test the heat preservation effect.

[0062] Under the condition of room temperature 20±2°C and nearly windless state, remove the cup lid of the thermos cup and place it for 2 hours, then pour boiling water to a position 5 mm below the water blocking part, place it vertically, and when the water temperature becomes 95±0.5°C, tighten the cup lid, and measure the water temperature in the cup after placing it for 6 hours. The standard requires that the heat preservation efficiency value after 6 hours ≥ 46°C meets the requirements. The final test temperatures after 6 hours are 50.9°C, 51.8°C, 50.4°C, 51.0°C, 50.7°C, 50.4°C, 50.7°C, 51.6°C, 51.9°C, 50.9°C, 52.2°C, 51.4°C, 51.7°C, 51.2°C, 51.4°C, 52.4°C, 52.4°C, 52.1°C, 51.9°C, 50.8°C, meeting the standard requirements.

[0063] Take 10 thermos cups made by the above-mentioned pressure vessel vacuum pumping and welding device and the pressure vessel vacuum pumping and welding method for cold preservation experiments to test the cold preservation effect.

[0064] Under the condition of room temperature 20±2°C and nearly windless state, remove the cup lid of the thermos cup and place it for 2 hours, then pour ice water to a position 5 mm below the mouth, place it vertically, and when the water temperature becomes 1±0.5°C, tighten the cup lid, and measure the water temperature in the cup after placing it for 12 hours. The standard requires that the cold preservation efficiency value after 12 hours ≤ 12.7°C meets the requirements. The final test temperatures after 6 hours are 11.8°C, 11.6°C, 11.8°C, 11.5°C, 11.6°C, 11.6°C, 11.7°C, 11.8°C, 12.0°C, 12.1°C, meeting the standard requirements.

[0065] In summary, a vacuum extraction welding device for a pressure vessel and a vacuum extraction welding method for a pressure vessel according to the present invention can directly extract vacuum from the pressure vessel body and the bottom of the pressure vessel in the placement cavity, and directly weld the pressure vessel body and the bottom of the pressure vessel. The vacuum extraction welding device for a pressure vessel has a simple structure, a simple process for vacuum extraction welding of the pressure vessel, low cost, and good sealing welding effect. The vacuum extraction welding method for a pressure vessel has simple steps for vacuum extraction welding, good sealing welding effect, high weld stability, and is not easily damaged. It eliminates the cumbersome steps of first opening a gap at the bottom of the pressure vessel, then welding the pressure vessel body and the bottom of the pressure vessel, then extracting vacuum inside the pressure vessel, and finally welding the gap opened at the bottom of the pressure vessel.

[0066] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly, and shall not be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit and essence of the present invention shall be covered within the protection scope of the present invention.

Claims

1. A vacuum pumping and welding device for a pressure vessel, comprising a frame, a placement chamber provided on the frame and having a placement cavity, a pressure vessel clamp provided in the placement cavity, a vacuum pumping mechanism communicated with the placement cavity, and a laser welding machine provided on the frame for hermetically welding the pressure vessel. It is characterized in that: The placement chamber includes a chamber body having the placement cavity. The placement cavity has an opening communicated with the outside. The placement chamber further includes a chamber door matched with the opening, and a sealing driving mechanism for hermetically pressing the chamber door at the opening. The pressure vessel clamp includes a lower jaw plate provided in the placement cavity, a first driving motor for driving the lower jaw plate to rotate, an upper jaw plate rotatably provided along its own axis direction above the lower jaw plate in the placement cavity, and a driving component for driving the upper jaw plate to move in a direction close to or away from the lower jaw plate. The first driving motor and the driving component are both hermetically arranged with the placement cavity. The vacuum pumping mechanism includes a low-vacuum obtaining module communicated with the placement cavity and a high-vacuum obtaining module communicated with the placement cavity. The low-vacuum obtaining module is communicated with the rear side of the placement cavity, and the high-vacuum obtaining module is communicated with the top of the placement cavity. The pressure vessel includes a pressure vessel body, and the pressure vessel body includes an outer tire and an inner tire connected to each other at one end. There is an open sandwich layer between the outer tire and the inner tire, and the mouth of the open sandwich layer faces the top of the placement cavity.

2. The vacuum extraction welding device for pressure vessels according to claim 1, wherein: The driving component includes a lead screw arranged in the vertical direction, a second driving motor for driving the lead screw to rotate, a roller matched with the lead screw, a guide post arranged in the placement cavity and parallel to the lead screw, and a slide plate slidably sleeved on the guide post. The roller is fixed to the slide plate, and the upper jaw plate is rotatably arranged on the slide plate along its own axis direction.

3. The vacuum extraction and welding device for pressure vessels according to claim 1, characterized in that: The placement chamber further includes a slide rail provided at the opening. A chute matched with the slide rail is opened on the chamber door. The sealing driving mechanism includes a first driving cylinder for driving the chamber door to reciprocate along the slide rail.

4. The vacuum extraction welding device for pressure vessels according to claim 3, characterized in that: The chamber door includes a front end cover provided with the chute, and a sealing cover slidably arranged on the front end cover and capable of moving in a direction close to or away from the opening. The sealing driving mechanism further includes a second driving cylinder for driving the sealing cover to move in a direction close to or away from the opening.

5. The vacuum pumping and welding device for pressure vessels according to claim 4, characterized in that: The chamber door further includes a guiding mechanism for guiding the movement of the sealing cover. The guiding mechanism includes a guiding hole provided on the front end cover and a guiding post fixed to the sealing cover and matched with the guiding hole.

6. The vacuum pumping and welding device for pressure vessels according to claim 1, characterized in that: The low-vacuum obtaining module includes a gas transfer vacuum pump, and the high-vacuum obtaining module includes a gas capture vacuum pump.

7. The vacuum extraction welding device for pressure vessels according to claim 1, characterized in that: The vacuum pumping and welding device further includes a laser welding machine adjusting mechanism provided on the frame. The laser welding machine is fixed to the laser welding machine adjusting mechanism. The laser welding machine adjusting mechanism includes a horizontal adjusting part, a vertical adjusting part, and a vertical adjusting part.

8. The vacuum extraction welding device for pressure vessels according to claim 1, characterized in that: The laser welding machine includes a laser head. A laser head insertion hole is formed in the side wall of the cabin body. The laser head extends into the placement cavity through the laser head insertion hole. The laser head and the laser head insertion hole are connected by a flexible welding bellows. A sealing lens is provided in the laser head.

9. A method for vacuum pumping and welding of a pressure vessel, characterized in that: It includes a pressure vessel vacuum welding device as described in any one of claims 1 to 8, and a pressure vessel to be welded. The pressure vessel includes a pressure vessel body and a pressure vessel bottom. The pressure vessel body includes an outer tire and an inner tire that are connected to each other at one end. There is an open sandwich between the outer tire and the inner tire. The end of the pressure vessel bottom cooperates with the other end of the outer tire to form an annular weld gap to be welded. The pressure vessel vacuum welding method is as follows: Step 1: Open the hatch door, clamp the pressure vessel body on the lower jaw plate, and clamp the pressure vessel bottom on the upper jaw plate. Step 2: Drive the sealing drive mechanism to drive the hatch door to seal the placement cavity. Step 3: Drive the low vacuum acquisition module to perform low vacuum pumping on the placement cavity. Step 4: Drive the high vacuum acquisition module to perform high vacuum pumping on the placement cavity. Step 5: Drive the drive assembly to drive the upper jaw plate to move downward, so that the pressure vessel bottom is pressed against the pressure vessel body, and the end of the pressure vessel bottom cooperates with the other end of the outer tire to form an annular weld gap to be welded (73). Step 6: Adjust the laser welding machine adjustment mechanism so that the light output port of the laser welding machine directly faces the weld gap to be welded. Step 7: Drive the first drive motor to drive the lower jaw plate to rotate, and drive the pressure vessel body and the container bottom to rotate synchronously. Drive the laser welding machine to weld the weld gap to be welded, so that a vacuum sealing sandwich is formed between the outer tire, the inner tire, and the pressure vessel bottom.

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