A vertical furnace body for coating the inner wall of an elongated tube

Abstract

The utility model discloses a vertical furnace body for the film plating of the inner wall of an elongated tube, which is provided with an inner guiding assembly, a translational force mechanism and a process step processing station in the furnace body. The process step processing station at least includes a vacuum pumping station, an ion bombardment cleaning station and a film plating station. The inner guiding assembly can be connected with the clamp for clamping the elongated tube in a sliding fit. The translational force mechanism can drive the clamp on the inner guiding assembly and the elongated tube to move between the various stations. The upper end of the furnace body is provided with a gas adsorption rod, an ion bombardment electrode device and a magnetron sputtering target that can be lifted, corresponding to the vacuum pumping station, the ion bombardment cleaning station and the film plating station respectively. The gas adsorption rod, the ion bombardment electrode device and the magnetron sputtering target are located in a vertical telescopic cabin respectively, which is isolated from the outside but can communicate with the inside of the furnace body. The gas adsorption rod, the ion bombardment electrode device and the magnetron sputtering target can all be lowered into the furnace body and inserted into the elongated tube. The utility model can realize the film plating of the elongated tube and ensure the film plating quality.

Description

Technical Field

[0001] This utility model belongs to the field of magnetron sputtering coating technology for the inner wall of slender tubes, specifically relating to a vertical furnace for coating the inner wall of slender tubes. Background Technology

[0002] Magnetron sputtering coating technology has been widely used in various industries to prepare hard films and functional films, such as protective films for molds and dies, wear-resistant films and friction-reducing films for worn workpieces, decorative films for various products touched by human hands, as well as various optical films, optoelectronic films, magnetic films, etc. The shapes and sizes of the workpieces to be coated are varied, and the structural design of magnetron sputtering targets is becoming increasingly mature, generally applicable to the coating of various workpieces.

[0003] Slender tubes are tubes with small cross-sections but long lengths. Coating their inner walls requires processes such as vacuuming inside the tube, argon ion bombardment cleaning, depositing the underlayer, and depositing the surface metal film. The design of coating equipment for coating the inner walls of slender tubes involves many technical challenges that need to be overcome. One of these challenges is the design of the furnace structure, which requires multiple process steps to be completed on the slender tube while maintaining a vacuum inside.

[0004] In addition, the following problems are encountered in the coating process of slender tubes in the furnace: 1. It is difficult to achieve a high vacuum and uniform vacuum degree inside the slender tube placed in the chamber (the background vacuum needs to be lower than 10E-4Pa). This is mainly because the internal space of the slender tube is narrow and long, and the vacuum process is easily affected by the gas resistance inside the tube, resulting in uneven vacuum degree between the two ends and the middle section of the tube. The gas pressure in the middle section is higher (experiments show that when evacuating a slender tube longer than three meters, the vacuum degree along the tube is inconsistent, and the vacuum degree in the middle section is low. It can be seen that it is very difficult to achieve a uniform vacuum inside a 10-meter-long slender tube); 2. Argon ion bombardment cleaning, underlayer coating and surface metal film coating all require gas distribution (argon) inside the tube. However, the internal space of the slender tube is narrow and long, making it difficult to achieve uniform gas distribution. Uneven gas distribution will lead to poor argon ion bombardment cleaning effect, uneven sputtering coating, or even failure to coat the film. Utility Model Content

[0005] The purpose of this invention is to provide a vertical furnace body for coating the inner wall of a slender tube.

[0006] The objective of this utility model is achieved through the following technical solution:

[0007] A vertical furnace body for coating the inner wall of a slender tube is characterized in that: the furnace body is provided with an internal guiding component, a translational force mechanism, and process step processing stations, the process step processing stations including at least a vacuuming station, an ion bombardment cleaning station, and a coating station; the internal guiding component can be slidably connected to a clamp holding the slender tube; the translational force mechanism can drive the clamp on the internal guiding component and the slender tube to move between the various stations; the upper end of the furnace body is respectively provided with a gas adsorption rod, an ion bombardment electrode device, and a magnetron sputtering target that can be raised and lowered for the vacuuming station, the ion bombardment cleaning station, and the coating station; the gas adsorption rod, the ion bombardment electrode device, and the magnetron sputtering target are respectively located in a vertical telescopic chamber at the upper end of the furnace body; the vertical telescopic chamber is isolated from the outside but can communicate with the inside of the furnace body; the gas adsorption rod, the ion bombardment electrode device, and the magnetron sputtering target can all be lowered into the furnace body and inserted into the slender tube.

[0008] A further technical solution of this utility model is as follows: the lower end of the gas adsorption rod is provided with gas adsorption material, and multiple process gas pipelines are provided inside the ion bombardment electrode device and the magnetron sputtering target, with the outlet ends of the multiple process gas pipelines distributed at different heights.

[0009] A further technical solution of this utility model is: a vacuum valve is provided at the lower end of the vertical telescopic chamber to isolate the vertical telescopic chamber from the interior of the furnace body.

[0010] A further technical solution of this utility model is as follows: the process steps include at least one waiting station for coating and at least one waiting station for unloading. The waiting station for coating, the vacuum station, the ion bombardment cleaning station, the coating station and the waiting station for unloading are arranged in a straight line inside the furnace.

[0011] A further technical solution of this utility model is as follows: the process steps include two types of coating stations, namely a bottom layer magnetron sputtering coating station for depositing the bottom layer and a surface layer magnetron sputtering coating station for depositing the surface metal layer.

[0012] A further technical solution of this utility model is: the furnace body is equipped with a vacuum system that can evacuate the furnace body and each vertical telescopic chamber.

[0013] A further technical solution of this utility model is as follows: the vacuum system includes a bellows molecular pump for drawing high vacuum in the vertical telescopic chamber, a vacuum pump for drawing low vacuum in the furnace body and the vertical telescopic chamber, and a furnace body molecular pump for drawing high vacuum in the furnace body. Furnace body molecular pumps are respectively provided at the upper and lower ends of the furnace body, and the bellows molecular pump is connected to the lower end of the vertical telescopic chamber.

[0014] A further technical solution of this utility model is: the vertical telescopic cabin is composed of multiple corrugated pipes connected in sequence.

[0015] A further technical solution of this utility model is that a low-temperature pump is also provided on the furnace body.

[0016] A further technical solution of this utility model is: a heating plate assembly is provided on the inner side wall of the furnace body.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. This utility model has at least a vacuuming station, an ion bombardment cleaning station, and a coating station set up inside the furnace. During the operation, the clamps and slender tubes on the internal guide assembly are moved between the stations by the translational force mechanism. At the same time, the gas adsorption rod, the ion bombardment electrode device, and the magnetron sputtering target are designed to be able to be lifted and lowered so that they can be inserted into the slender tube to complete the required process, thereby finally achieving the coating of the slender tube.

[0019] 2. This utility model uses a gas adsorption rod to adsorb the gas inside a slender tube. By adsorbing the gas in the middle section of the slender tube by the gas adsorption rod, the slender tube can achieve a background vacuum and a uniform vacuum degree in a short time.

[0020] 3. This utility model further includes multiple process gas pipelines in the ion bombardment electrode device and the magnetron sputtering target, and the outlet ends of the multiple process gas pipelines are distributed at different heights. This achieves the purpose of uniform gas distribution in the slender tubes by segmenting the gas distribution during ion bombardment cleaning and coating, thereby better ensuring the coating quality. Attached Figure Description

[0021] Figure 1 This is a three-dimensional schematic diagram of the furnace body, the upper components, and the steel structure platform according to an embodiment of the present utility model;

[0022] Figure 2 This is a three-dimensional schematic diagram of the furnace body and the upper components according to an embodiment of the present utility model;

[0023] Figure 3 This is a three-dimensional schematic diagram of the furnace body according to an embodiment of the present utility model;

[0024] Figure 4 This is a front view schematic diagram of the furnace body according to an embodiment of the present utility model;

[0025] Figure 5 yes Figure 4 Schematic diagram of the cross section at point II-I;

[0026] Figure 6 This is a left-side view of the furnace body according to an embodiment of the present invention;

[0027] Figure 7 This is a right-side view of the furnace body according to an embodiment of the present invention;

[0028] Figure 8 This is a schematic diagram of the structure of the fixture and the slender tube being fed into the furnace for coating according to an embodiment of the present invention.

[0029] Figure 9 yes Figure 8 Enlarged schematic diagram of section II-IV;

[0030] Figure 10 yes Figure 8 Enlarged schematic diagram of section II-V;

[0031] Figure 11 This is a schematic diagram of the upper lifting structure and corrugated pipe of the furnace body according to an embodiment of the present utility model;

[0032] Figure 12 yes Figure 11 Enlarged schematic diagram of section III-I;

[0033] Figure 13 This is a schematic diagram of the structure of a section of a corrugated pipe according to an embodiment of the present invention;

[0034] Figure 14 This is a schematic diagram of the lifting structure according to an embodiment of the present utility model;

[0035] Figure 15 This is a schematic diagram of the structure of the magnetron sputtering target according to an embodiment of the present invention;

[0036] Figure 16 This is a top view of a magnetron sputtering target according to an embodiment of the present invention;

[0037] Figure 17 This is a schematic diagram showing the distribution of the outlet end of the process gas pipeline according to an embodiment of this utility model.

[0038] Figure 18 This is a cross-sectional schematic diagram of the target body of the magnetron sputtering target according to an embodiment of the present invention;

[0039] Figure 19 This is a schematic diagram of the structure of the gas adsorption rod according to an embodiment of the present invention.

[0040] Figure 20 This is a schematic diagram of the structure when a slender tube is clamped onto the fixture of this utility model embodiment;

[0041] Figure 21 yes Figure 20 Schematic diagram of cross-section at point I-I.

[0042] Meaning of the labels in the attached diagram:

[0043] 1-Furnace body; 2-Steel structure platform; 3-Flange; 4-Bellowed pipe; 5-Upper steel structure support; 6-Furnace opening; 7-Furnace door; 8-Furnace body molecular pump; 9-Cryogenic pump; 10-Vacuum pump; 11-Heating plate assembly; 12-Base; 13-Bellowed pipe molecular pump; 14-Mounting pipe seat; 15-Vacuum valve; 16-Third V-shaped guide rail; 17-Third flat guide wheel assembly; 18-Waiting for coating station; 19-Vacuuming station; 20-Ion bombardment cleaning station; 2 1- Bottom film magnetron sputtering coating station; 22- Top film magnetron sputtering coating station; 23- Waiting for furnace exit station; 24- Translation drive motor; 25- Synchronous belt; 26- Synchronous pulley; 27- Cylinder; 28- External electrode connector; 29- Slender tube; 30- Upper clamp; 31- First V-shaped guide wheel assembly; 32- Lower clamp; 33- First planar guide rail; 34- Connecting shaft; 35- Third V-shaped guide wheel assembly; 36- Second V-shaped guide rail; 37- Mounting base; 38- Offset 39-Piercing wire; 40-Inner electrode connector; 41-Conductive rod; 42-Gas adsorption rod; 43-Ion bombardment electrode device; 44-Bottom layer film magnetron sputtering target; 45-Surface layer film magnetron sputtering target; 46-Telescopic hydraulic cylinder; 47-Telescopic guide rail; 48-Telescopic guide slider; 49-Slider connecting rod; 50-Oxygen-free copper pad; 51-Spacer ring; 52-Support rod; 53-Coating rotary motor; 54-Top connector; 55-Air inlet connector; 56-Sealing connection structure; 56-Target body; 57-Limit seat; 58-Process gas pipeline; 59-Gas outlet; 60-Target seat; 61-Insulation kit; 62-Magnet assembly; 63-Anode cooling water pipeline; 64-Anode; 65-Cathode target material; 66-Cathode cooling water chamber; 67-Electrifying head; 68-Fixed mounting plate; 69-Limit ring; 70-Mounting and fixing pipe; 71-Gas adsorption material; 72-Clamp; 73-Sleeve; 74-Base plate; 75-Perforation; 76-Insulation layer. Detailed Implementation

[0044] The present invention will be further described below with reference to embodiments.

[0045] In the description of this utility model, it should be understood that the directional descriptions, such as up, down, front, back, left, right, etc., indicate the directional or positional relationships based on the directional or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0046] In the description of this utility model, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. If "first" or "second" is used in the description, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0047] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0048] Example:

[0049] This embodiment uses a vertical furnace capable of coating the inner wall of a slender tube with a diameter of approximately 150 mm and a length of approximately 10 m as an example. Figures 1 to 5 As shown, the furnace body 1 in this embodiment has a relatively narrow width but a height equivalent to three stories. It is installed vertically on the base 12, serving as a vacuum coating chamber that provides a high-vacuum environment for coating operations on the inner wall of the slender tube 29. A steel structure platform 2 is designed around the furnace body 1, providing a safe, reliable, and operational platform that meets the requirements of the production process.

[0050] The furnace body 1 has a furnace opening 6 and a furnace door 7 that can seal and cover the furnace opening 6 on one side. The furnace door 7 is installed using a push-pull structure. When the furnace door 7 is pulled out to one side, the furnace opening 6 is opened.

[0051] The furnace body 1 is equipped with an internal guide assembly, a translational force mechanism, a process step processing station, and a vacuum system.

[0052] The internal guide assembly includes an internal upper guide rail assembly and an internal lower guide wheel assembly located at the upper and lower ends, such as... Figure 9 and Figure 10 As shown, the internal upper guide rail assembly of this embodiment includes two third V-shaped guide rails 16 arranged opposite to each other on the two side walls, and the internal lower guide wheel assembly includes a third planar guide wheel group 17 and a third V-shaped guide wheel group 35 installed side by side at the bottom of the furnace body. The guide wheels of the third planar guide wheel group 17 and the third V-shaped guide wheel group 35 correspond one-to-one, and the guide wheels of the third planar guide wheel group 17 and the third V-shaped guide wheel group 35 are connected to each other through a connecting shaft 34, so that the guide wheels at the bottom of the furnace body 1 can rotate synchronously.

[0053] like Figure 6As shown, the translational motion mechanism of this embodiment includes a translational drive motor 24 and synchronous pulleys 26 that are arranged one-to-one with the connecting shaft 34. The translational drive motor 24 and the synchronous pulleys 34 are both located on the outside of the furnace body 1. The synchronous pulleys 26 are connected to the connecting shaft 34 one-to-one. Adjacent synchronous pulleys 26 are connected to each other by a synchronous belt 25. The synchronous pulley 26 closest to the translational drive motor 24 is connected to the output end of the translational drive motor 24 by a synchronous belt 25. Finally, the translational drive motor 24 can drive the guide wheel at the bottom of the furnace body 1 to rotate synchronously, thereby driving the clamp and the slender tube 29 on it to move between various workstations.

[0054] like Figure 5 As shown, the process steps in this embodiment include a waiting coating station 18, a vacuuming station 19, an ion bombardment cleaning station 20, a bottom layer magnetron sputtering coating station 21, a surface layer magnetron sputtering coating station 22, and a waiting furnace exit station 23. These stations are arranged in a straight line inside the furnace body 1.

[0055] At the upper end of the furnace body 1, corresponding to the vacuuming station 19, ion bombardment cleaning station 20, bottom film magnetron sputtering coating station 21, and surface film magnetron sputtering coating station 22, there are top holes, and correspondingly, there are liftable gas adsorption rods 41, ion bombardment electrode devices 42, bottom film magnetron sputtering targets 43, and surface film magnetron sputtering targets 44. The gas adsorption rods 41, ion bombardment electrode devices 42, bottom film magnetron sputtering targets 43, and surface film magnetron sputtering targets 44 are all vertically arranged and elongated, able to penetrate into the furnace body 1 and be inserted into the slender tube 29. The lifting and lowering of the gas adsorption rods 41, ion bombardment electrode devices 42, bottom film magnetron sputtering targets 43, and surface film magnetron sputtering targets 44 are achieved through lifting mechanisms.

[0056] At the upper end of the furnace body 1, corresponding to the vacuum station 19, ion bombardment cleaning station 20, bottom film magnetron sputtering coating station 21, and surface film magnetron sputtering coating station 22, there are vertical telescopic chambers that are isolated from the outside world but can communicate with the inside of the furnace body. The gas adsorption rod 41, ion bombardment electrode device 42, bottom film magnetron sputtering target 43, and surface film magnetron sputtering target 44 are respectively installed in the corresponding vertical telescopic chambers, with only the upper head for connecting to the outside world exposed above the vertical telescopic chamber.

[0057] In this embodiment, vacuum valves 15 are respectively installed at the upper end of the furnace body 1 corresponding to the vacuuming station 19, ion bombardment cleaning station 20, bottom film magnetron sputtering coating station 21, and surface film magnetron sputtering coating station 22, and mounting bases 14 are connected above the vacuum valves 15. The vertical telescopic chamber in this embodiment is composed of multiple corrugated pipes 4 connected sequentially, and flanges 3 are respectively provided at the upper and lower ends of the vertical telescopic chamber and between adjacent corrugated pipes 4. The flange 3 at the lower end of the vertical telescopic chamber is fixedly connected to the mounting base 14. Furthermore, as shown... Figure 14 As shown, support rods 51 are respectively provided at the four lower corners of the flange 3 at the lower end of the vertical telescopic chamber. The lower ends of the support rods 51 are fixedly connected to the upper part of the furnace body 1 to form a support. The upper ends of the gas adsorption rod 41, the ion bombardment electrode device 42, the bottom film magnetron sputtering target 43, and the surface film magnetron sputtering target 44 are respectively connected to the flange 3 at the upper end of the vertical telescopic chamber, and the ends are exposed outside the bellows 4, so that they can be connected to the outside world for cooling water, electricity, and gas.

[0058] like Figure 14 As shown, the lifting mechanism includes vertical telescopic components respectively installed between adjacent flanges 3. The telescopic components extend and retract the bellows 4 between adjacent flanges 3. Each telescopic component includes two telescopic hydraulic cylinders 45 arranged diagonally. The upper and lower ends of the bellows 4 are fixedly connected to the corresponding flanges 3. An oxygen-free copper gasket 49 is provided between the end face of the bellows 4 and the surface of the flange 3 to form a sealed connection.

[0059] In this embodiment, an upper rigid structure support 5 is provided on the top of the furnace body 1 to support the upper structure. The lifting mechanism and the bellows 4 are both located inside the upper rigid structure support 5. Vertical telescopic guide rails 46 are provided on both sides of the bellows 4 inside the upper rigid structure support 5. Sliding rods 48 are provided on both sides of the bellows 4. Telescopic guide sliders 47 are provided at the outer ends of the sliding rods 48. The telescopic guide sliders 47 are slidably connected to the telescopic guide rails 46, thereby ensuring that the vertical extension and retraction of the bellows 4 can be carried out stably.

[0060] Figure 13 The structure of one section of the bellows 4 is shown, in a compressed state. Bellows 4 is an existing component purchased directly from the market, so its structure is only briefly described here: Figure 13 The corrugated pipe 4 shown is composed of seven telescopic pipe sections connected sequentially. Spacer rings 50 are provided between the pipe sections to connect them together. The guide mechanism between the spacer rings 50 is built into the corrugated pipe and will not be described further here. In this embodiment, a slider connecting rod 48 is provided on both sides of each spacer ring 50.

[0061] The magnetron sputtering target in this embodiment is a planar target. Its main improvement lies in the presence of an anode 64 and multiple independent process gas pipelines 58 (because a bias voltage must be applied to the wall of the slender pipe during coating, which shields the anode (furnace wall), so an anode is necessary). The remaining structure is designed according to the traditional magnetron sputtering target structure, and therefore will only be briefly described here. Figures 15 to 18As shown, the magnetron sputtering target mainly includes a top connector 53, a sealing connection structure 55, a target body 56, and a limiting seat 57. The sealing connection structure 55 is used for sealing connection to the flange 3 at the upper end of the vertical telescopic chamber. The top connector 53 is located on the outer side of the upper end of the vertical telescopic chamber, and the target body 56 is located on the inner side of the vertical telescopic chamber. A coating rotary motor 52 is provided on the top connector 53. The rotation of the coating rotary motor 52 is transmitted to the target body 56 through an intermediate shaft, thereby driving the target body 56 to rotate. A cooling water connector for connecting to an external cooling water circulation system is also provided on the top connector 53. The cooling water connector is connected to the cooling water channel inside the target body 56.

[0062] like Figure 18 As shown, the target body 56 in this embodiment is provided with a target base 60. A cathode target 65 is fixedly installed on the front of the target base 60. A mountain-shaped magnet assembly 62 is provided inside the target base 60. A cathode cooling water chamber 66 is formed in the space of the magnet assembly 62. An anode 64 is connected to both sides of the target base 60 through an insulating kit 61. There is a certain gap between the anode 64 and the target base 60. The anode 64 is insulated from the target base 60. An anode cooling water pipe 63 is provided on the side of the anode 64. The cathode cooling water chamber 66 and the anode cooling water pipe 63 are both part of the cooling water channel. Since the cooling water channel is the same as the structure of a conventional magnetron sputtering target, it will not be described in detail here.

[0063] In this embodiment, four process gas pipes 58 are respectively provided on both sides of the rear of the target holder 60, such as... Figure 17 As shown, the outlet ends of each process gas pipeline 58 are distributed at different heights, and each process gas pipeline 58 has multiple outlet holes 59 at its outlet end. Eight inlet connectors 54 are correspondingly provided on the side of the top connector 53, and each of the eight inlet connectors 54 is connected to a process gas pipeline 58, allowing each process gas pipeline 58 to be supplied with gas independently. The connection between the process gas pipeline 58 and the top connector 53, as well as the connection to the external gas source, are the same as the structure of a traditional magnetron sputtering target, and therefore will not be described in detail here. During use, by introducing gas through multiple process gas pipelines 58, the gas can be delivered to different height positions within the slender tube 29, achieving segmented gas distribution and ultimately achieving uniform gas distribution.

[0064] The bottom layer magnetron sputtering target 43 and the top layer magnetron sputtering target 44 have the same structure, except that the cathode target 65 is made of different materials. In this embodiment, the cathode target 65 of the bottom layer magnetron sputtering target 43 is made of Cr, while the cathode target 65 of the top layer magnetron sputtering target 44 is made of the metal material required for the surface layer.

[0065] The ion bombardment electrode device 42 in this embodiment has a shape similar to the magnetron sputtering target described above, adopting a long, flat design. The magnet assembly is eliminated, while the rotating mechanism, cooling water channel, and gas supply channel are retained. Its main structure is the same as that of a traditional ion bombardment electrode, therefore its main structure will not be described in detail. The difference lies in the design of multiple process gas pipes 58, specifically eight. The design of the process gas pipes 58 is the same as that of the film magnetron sputtering target described above. The outlet ends of each process gas pipe 58 are distributed at different heights, and each process gas pipe 58 has multiple outlet holes 59 at its outlet end. During use, gas is independently introduced through multiple process gas pipes 58 to achieve segmented gas distribution, ultimately achieving uniform gas distribution.

[0066] like Figure 19 The diagram shows the structure of the gas adsorption rod 41. It is rod-shaped with an electric induction head 67 at the upper end and a mounting plate 68 near the upper end. The mounting plate 68 is sealed to the flange 3 at the upper end of the vertical telescopic chamber. A limiting ring 69 is located at the lower end, and a mounting tube 70 is located below the limiting ring 69. Gas adsorption material 71 is connected to the lower end of the mounting tube 70. The gas adsorption material 71 is a commercially available component and will not be described in detail; it is cylindrical as shown in the diagram. The electric induction head 67 connects to an external power source to provide activation power for the gas adsorption material 71. The operating principle and electrical connection structure of the gas adsorption material 71 are conventional technologies and will not be described in detail.

[0067] The vacuum system of this embodiment includes a bellows molecular pump 13, a vacuum pump 10, and a furnace body molecular pump 8. A bellows molecular pump 13 is installed on the furnace body 1 corresponding to each vertical telescopic chamber. The bellows molecular pump 13 is connected to the mounting base 14, thereby arranging the bellows molecular pump 13 between the vacuum valve 15 and the lower end of the vertical telescopic chamber. The bellows molecular pump 13 is used to evacuate the vertical telescopic chambers to a high vacuum. The vacuum pump 10 is connected to the furnace body 1 and is used to evacuate the furnace body 1 and the vertical telescopic chambers to a low vacuum. Multiple furnace body molecular pumps 8 are installed at the upper and lower ends of the furnace body 1 to evacuate the furnace body 1 to a high vacuum.

[0068] In this embodiment, a heating plate assembly 11 is provided on the inner wall of the furnace body 1. The heating plate assembly 11 is used to heat the interior of the furnace body 1 and the workpiece. Six cryogenic pumps 9 are respectively provided on the outer side of one side wall and the outer side of the rear wall of the furnace body 1. The six cryogenic pumps 9 are arranged vertically at intervals. The number of cryogenic pumps 9 can be adjusted according to actual needs. The cryogenic pumps 9 are responsible for obtaining a high vacuum inside the furnace. Choosing cryogenic pumps 9 is more conducive to removing water vapor.

[0069] During the coating process, the slender tube 29 will be clamped in a fixture, such as Figure 20 and Figure 21As shown, the clamps are respectively provided with an upper clamp 30 and a lower clamp 32 at both ends of the slender tube. In this embodiment, the upper clamp 30 is a clamping plate with two clamping holes. A clamping hoop 72 is provided at the outer end of the clamping holes. An insulating layer 76 is provided on the inner wall of both the clamping holes and the clamping hoop 72, so that the upper clamp 30 is completely insulated from the slender tube 29. The two sides of the upper clamp 30 are respectively provided with a first V-shaped guide wheel group 31, which can be connected to the third V-shaped guide rail 16 inside the furnace body 1.

[0070] The lower clamp 32 includes a base plate 74 and two sleeves 73 mounted on the base plate 74. A clamp 72 is provided at the outer end of each sleeve 73. A through hole 75 is provided on the base plate 74 corresponding to the middle of each sleeve 73. The diameter of the through hole 75 is smaller than the outer diameter of the slender tube 29. An insulating layer 76 is provided on the inner wall of the sleeves 73, the inner wall of the clamps 72, and the portion of the base plate 74 located inside the sleeves 73, ensuring complete insulation between the lower clamp 32 and the slender tube 29. A second V-shaped guide rail 36 and a first flat guide rail 33 are provided on the surface of the base plate 74 away from the upper clamp 30. The first flat guide rail 33 and the second V-shaped guide rail 36 can respectively cooperate with the third flat guide wheel group 17 and the third V-shaped guide wheel group 35 inside the furnace body 1. The third flat guide wheel group 17 and the third V-shaped guide wheel group 35 can support the first flat guide rail 33 and the second V-shaped guide rail 36 on them.

[0071] The V-shaped guide wheel assembly consists of multiple guide wheels with V-shaped grooves on their surfaces arranged in sequence. The planar guide wheel assembly consists of multiple guide wheels with planar surfaces arranged in sequence. The V-shaped guide rail has a triangular front cross-section and can cooperate with the guide wheels of the V-shaped guide wheel assembly. The front of the planar guide rail is flat and can cooperate with the guide wheels of the planar guide wheel assembly.

[0072] The number of clamping holes on the upper clamp 30 and sleeves 73 on the lower clamp 32 is set according to the number of slender tubes to be processed each time. The coating equipment in this embodiment can process two slender tubes 29 each time, so the number of clamping holes and sleeves 32 is two. It can be seen that the number of clamping holes and sleeves 32 is not limited to this.

[0073] In this embodiment, a slender tube bias connection assembly is provided on the upper surface of the base plate 74. The slender tube bias connection assembly includes a mounting base 37 and a conductive rod 40. The conductive rod 40 is mounted on the mounting base 37 and can move axially. A spring is provided on the conductive rod 40 to provide cushioning and pressure during docking. Of course, the conductive rod 40 is insulated from the mounting base 37. In use, one end of the conductive rod 40 near the sleeve 73 is connected to the slender tube 29 through a bias wire 38, while the other end docks with the bias external assembly on the furnace body 1.

[0074] In this embodiment, bias external components are respectively provided on the side wall of the furnace body 1 for the ion bombardment cleaning station 20, the bottom film magnetron sputtering coating station 21, and the surface film magnetron sputtering coating station 22, such as... Figure 10 As shown, the external bias assembly includes a bias docking telescopic mechanism, an external electrode connector 28, and an internal electrode connector 39. The bias docking telescopic mechanism is installed on the outside of the furnace body 1. In this embodiment, the bias docking telescopic mechanism is specifically a cylinder 27. The piston rod of the cylinder 27 extends into the furnace body 1. The internal electrode connector 39 is located on the piston rod of the cylinder 27, and the external electrode connector 28 is located on the side wall of the furnace body 1. The internal electrode connector 39 and the external electrode connector 28 are connected by a bias wire 38. During ion bombardment cleaning, the external electrode connector 28 is grounded through the wire. During sputtering coating, the external electrode connector 28 is connected to the negative terminal of the bias power supply. Of course, the internal and external electrode connectors are insulated from the furnace body 1 and the cylinder 27. After the fixture is moved into place, when it is necessary to connect the external bias assembly to the slender tube bias connection assembly, the cylinder 27 is activated. The piston rod of the cylinder 27 extends, so that the inner electrode connector 39 is pressed against the end face of the conductive rod 40, thereby achieving connection.

[0075] The usage process of furnace body 1 in this embodiment is as follows:

[0076] Before coating, the slender tube 29 is clamped onto the fixture. The slender tube 29 passes through the clamping hole of the upper fixture 30 and is then inserted into the sleeve 73 of the lower fixture 32, and the clamping clamp 72 is locked to complete the clamping. After clamping, the material is fed into the furnace body 1. The upper fixture 30 is slidably connected to the internal upper guide rail assembly inside the furnace body 1, and the lower fixture 32 is supported on the internal lower guide wheel assembly inside the furnace body 1.

[0077] For ease of explanation, we will refer to the slender tube 29 on the fixture that is furthest from the furnace opening 6 as the first slender tube, and the other as the second slender tube. First, start the motor of the translational power mechanism so that the second slender tube is in the waiting coating station 18. At this time, the first slender tube is in the vacuum station 19. Close the furnace door 7 and enter the coating process. The first slender tube is coated first, and then the second slender tube is coated after that.

[0078] The coating process specifically includes the following steps:

[0079] Step 1: Vacuuming inside furnace body 1: Open all vacuum valves 15 at the top of furnace body 1, and start vacuum pump 10 to create a low vacuum inside furnace body 1 and the corrugated tube 4. Start heating plate assembly 11 to heat inside furnace body 1 and the slender tube 29. Start furnace body molecular pump 8 and cryogenic pump 9 to create a high vacuum inside furnace body 1, and start corrugated tube molecular pump 13 to create a high vacuum inside the corrugated tube 4 corresponding to each station. When the furnace body 1 and the upper and lower sections of the first slender tube reach the background vacuum, start the lifting mechanism at the top of vacuum station 19 to compress the corrugated tube 4, causing the gas adsorption rod 41 to descend and insert into the first slender tube until it reaches the middle section of the first slender tube. The gas adsorption rod 41 is energized to assist in gas intake in the middle section of the first slender tube, increasing the vacuum level in the middle section of the first slender tube to achieve the required vacuum level and uniformity. Subsequently, the lifting mechanism at the upper end of the vacuum station 19 is activated, causing the gas adsorption rod 41 to rise and reset, and the vacuum valve 15 at the upper end of the vacuum station 19 is closed, while the bellows molecular pump 13 maintains the vacuum in the space inside the bellows 4.

[0080] The second step is argon glow discharge ion bombardment cleaning: The translational motion mechanism is activated to transfer the first slender tube to the ion bombardment cleaning station 20. The cylinder 27 of the bias external connection component is activated, causing the inner electrode connector 39 to be directly pressed against the end face of the conductive rod 40 of the bias connection component of the slender tube, achieving docking, while the outer electrode connector 28 is grounded. The lifting mechanism corresponding to the ion bombardment cleaning station 20 is activated to lower the ion bombardment electrode device 42 and insert it into the first slender tube. Argon gas is supplied to the first slender tube in sections through the eight process gas pipes 58 of the ion bombardment electrode device 42, achieving uniform gas distribution within the first slender tube and ultimately reaching 1 Pa. The ion bombardment electrode device 42 is energized, inputting a positive high voltage to provide a high-voltage electric field within the space of the first slender tube, generating argon glow discharge plasma and bombarding the tube wall, thus achieving ion bombardment cleaning. After the operation is completed, the ion bombardment electrode device 42 is powered off and the gas supply is shut off. The cylinder 27 of the bias external component retracts and separates from the conductive rod 40. The corresponding lifting mechanism is activated to raise and reset the ion bombardment electrode device 42, and the corresponding vacuum valve 15 is closed, while the bellows molecular pump 13 maintains a vacuum inside the bellows 4.

[0081] The third step is to deposit the bottom layer film: The translational force mechanism is activated to transfer the first slender tube to the vacuum station 19. Following the vacuuming process in the first step, a high vacuum is evacuated again inside the first slender tube, achieving a vacuum level of 5 x 10⁻² Pa. The translational force mechanism is then activated to transfer the first slender tube to the bottom layer film magnetron sputtering coating station 21. The cylinder 27 of the bias external component is activated, causing the inner electrode connector 93 to align with the conductive rod 40. The outer electrode connector 28 at this station is connected to the negative terminal of the bias power supply, applying a negative bias voltage to the slender tube. The corresponding lifting mechanism is activated to lower the bottom layer film magnetron sputtering target 43 and insert it into the first slender tube. Argon gas is supplied to the first slender tube in sections through the eight process gas pipes 58 on the bottom layer film magnetron sputtering target 43, ensuring uniform gas distribution inside and achieving a pressure of 0.4 Pa. The bottom layer magnetron sputtering target 43 is activated to begin depositing a Cr film, forming the bottom layer film. Once the set thickness is reached, the bottom layer magnetron sputtering target 43 is stopped, and the gas supply is halted. The cylinder 27 of the bias external component is activated, causing the internal electrode connector 39 to separate from the conductive rod 40. The corresponding lifting mechanism is activated, causing the bottom layer magnetron sputtering target 43 to rise and reset. The corresponding vacuum valve 15 is closed, and the bellows molecular pump 13 maintains a vacuum inside the bellows 4.

[0082] Step 4, Surface Metal Coating: Activate the translational motion mechanism to move the first slender tube back to the vacuum station 19. Following the vacuuming process in Step 1, evacuate the first slender tube again to a high vacuum of 5 x 10⁻² Pa. Activate the translational motion mechanism to transfer the first slender tube to the surface film magnetron sputtering coating station 22. Activate the cylinder 27 of the external bias assembly to align the inner electrode connector 39 with the conductive rod 40. The outer electrode connector 28 at this station is connected to the negative terminal of the bias power supply, applying a negative bias to the slender tube. Activate the corresponding lifting mechanism to lower the surface film magnetron sputtering target 44 and insert it into the first slender tube. Argon gas is supplied to the first slender tube in sections through the eight process gas pipes 58 on the surface film magnetron sputtering target 44, ensuring uniform gas distribution inside and reaching a pressure of 0.4 Pa. The surface film magnetron sputtering target 44 is started to deposit a metal film. Once the set thickness is reached, the surface film magnetron sputtering target 44 is stopped, and the gas supply is stopped. The cylinder 27 of the bias external component is activated, causing the internal electrode connector 39 to separate from the conductive rod 40. The corresponding lifting mechanism is activated, causing the surface film magnetron sputtering target 44 to rise and reset. The corresponding vacuum valve 15 is closed, and the bellows molecular pump 13 maintains a vacuum inside the bellows 4.

[0083] At this point, the coating process for the first slender tube is complete. The first slender tube is then moved to the waiting-to-be-out-of-furnace station 23.

[0084] The next step is to coat the second slender tube, which is done in the manner described in steps one through four above.

[0085] After the coating of the two slender tubes 29 is completed, vacuuming continues, but heating is stopped, and the slender tubes 92 are cooled to the specified temperature along with the furnace body 1. Gas is introduced into the furnace body 1, the furnace door 7 is opened, and the translational force mechanism is started, so that the second slender tube moves to the waiting coating station 18. At this time, the first slender tube is located at the vacuum station 19, and then the subsequent slender tubes can be unloaded.

[0086] The above embodiments of this utility model are not intended to limit the scope of protection of this utility model. The implementation of this utility model is not limited thereto. All other modifications, substitutions or alterations made to the above structure of this utility model based on the above content of this utility model and in accordance with the common technical knowledge and conventional means in the field, without departing from the basic technical idea of ​​this utility model, shall fall within the scope of protection of this utility model.

Claims

1. A vertical furnace body for coating the inner wall of a slender tube, characterized in that: The furnace body is equipped with an internal guide assembly, a translational force mechanism, and process step processing stations. The process step processing stations include at least a vacuuming station, an ion bombardment cleaning station, and a coating station. The internal guide assembly can be slidably connected to a clamp holding a slender tube. The translational force mechanism can drive the clamp and slender tube on the internal guide assembly to move between the various stations. The upper end of the furnace body is equipped with a gas adsorption rod, an ion bombardment electrode device, and a magnetron sputtering target that can be raised and lowered, corresponding to the vacuuming station, the ion bombardment cleaning station, and the coating station, respectively. The gas adsorption rod, the ion bombardment electrode device, and the magnetron sputtering target are located in a vertical telescopic chamber at the upper end of the furnace body. The vertical telescopic chamber is isolated from the outside but can communicate with the interior of the furnace body. The gas adsorption rod, the ion bombardment electrode device, and the magnetron sputtering target can all be lowered into the furnace body and inserted into the slender tube.

2. The vertical furnace body for coating the inner wall of a slender tube according to claim 1, characterized in that: The lower end of the gas adsorption rod is provided with gas adsorption material, and the ion bombardment electrode device and the magnetron sputtering target are provided with multiple process gas pipes, the outlet ends of the multiple process gas pipes are distributed at different heights.

3. The vertical furnace body for coating the inner wall of a slender tube according to claim 1, characterized in that: The lower end of the vertical telescopic chamber is equipped with a vacuum valve that can isolate the vertical telescopic chamber from the interior of the furnace.

4. The vertical furnace body for coating the inner wall of a slender tube according to claim 1, characterized in that: The process steps also include at least one waiting station for coating and at least one waiting station for unloading. The waiting station for coating, vacuuming station, ion bombardment cleaning station, coating station and waiting station for unloading are arranged in a straight line inside the furnace.

5. The vertical furnace body for coating the inner wall of a slender tube according to claim 4, characterized in that: The process steps include two types of coating stations: a bottom layer magnetron sputtering coating station for depositing the bottom layer and a surface layer magnetron sputtering coating station for depositing the surface metal layer.

6. The vertical furnace body for coating the inner wall of a slender tube according to claim 1, characterized in that: The furnace body is equipped with a vacuum system that can evacuate the furnace body and each vertical telescopic chamber.

7. The vertical furnace body for coating the inner wall of a slender tube according to claim 6, characterized in that: The vacuum system includes a bellows molecular pump for drawing high vacuum in the vertical telescopic chamber, a vacuum pump for drawing low vacuum in the furnace body and the vertical telescopic chamber, and a furnace body molecular pump for drawing high vacuum in the furnace body. Furnace body molecular pumps are provided at the upper and lower ends of the furnace body, and the bellows molecular pump is connected to the lower end of the vertical telescopic chamber.

8. The vertical furnace body for coating the inner wall of a slender tube according to claim 1, characterized in that: The vertical telescopic cabin is composed of multiple corrugated pipe sections connected in sequence.

9. The vertical furnace body for coating the inner wall of a slender tube according to claim 1, characterized in that: The furnace body is also equipped with a cryogenic pump.

10. The vertical furnace body for coating the inner wall of a slender tube according to claim 1, characterized in that: The inner wall of the furnace body is provided with a heating plate assembly.

Images