A non-glass device for connecting an exhaust platform of a laser gyroscope

Abstract

A non-glass device for connecting a laser gyroscope to an exhaust platform, characterized in that: a bellows 1 is docked and installed with the vacuum exhaust platform, and the other end is connected to a three-way joint, the other end of the three-way joint is connected to a bellows 2, the ferrule joint of the bellows 2 is connected to the laser gyroscope, the laser gyroscope is electrically connected to a high-voltage power supply, the third port of the three-way joint is connected to a storage tank through a sealing joint, the storage tank is made of non-glass material, and is a hollow flat-bottomed circular cylinder with an upper opening, and a getter is arranged on the flat bottom of the inner cavity. The bellows, the sealing joint, and the ferrule joint are used to respectively realize flexible connection and sealed docking, so that the connection and disassembly efficiency of each component between the laser gyroscope and the vacuum exhaust platform is significantly improved compared with glass sintering, while avoiding the safety hazards of the glass structure, realizing the fire-free operation of the laser gyroscope, which is safe, convenient, and has good airtightness. In addition, the diversion device effectively reduces the interference of thermal deformation, improves the measurement accuracy of the laser gyroscope, and has high practical value.

Description

Technical Field

[0001] The invention belongs to the technical field of inertial navigation equipment manufacturing, and in particular relates to a non-glass device used for connecting a laser gyroscope to an exhaust platform. Background Art

[0002] Laser gyroscope is a sensor used to measure the angular velocity of moving objects. It is one of the commonly used sensor types in modern inertial navigation technology. Its general form is a ring-shaped helium-neon laser resonator. Common laser resonators include quadrilaterals and triangles. Like conventional helium-neon lasers, the laser gyroscope is filled with helium-neon (He-Ne) gas at a certain pressure, which is called the working substance. Ensuring the purity of the working substance is the core of maintaining the life of the laser gyroscope. Due to the large pressure difference between the inside and outside of the laser gyroscope cavity (about 0.9 atmospheres), it is a difficult challenge for the laser gyroscope manufacturing process to prevent atmospheric leakage during the use and storage period of about 10 years. In addition, other non-working gas molecules attached to the inner surface of the microcrystalline glass cavity and the inner surface of the electrode will be slowly released to affect the purity of the working gas. As a result, the laser gyroscope gain decreases, the laser intensity weakens, and even fails to reach the conditions for laser generation, making the laser gyroscope ineffective. Therefore, the increase of impurity gas is one of the key factors affecting the life of the laser gyroscope. In order to overcome the influence of impurity gas on the life of laser gyro, laser gyro needs to be installed with getter, which is generally composed of zirconium, aluminum, etc. After high temperature activation, the getter can adsorb impurity gas molecules at room temperature without adsorbing helium-neon gas. However, the activation of getter is generally implemented after the "aging" of laser gyro is completed. Therefore, when the laser gyro is connected to the vacuum exhaust table for "aging", an auxiliary getter is needed to adsorb the impurity gas generated during the "aging" process.

[0003] The laser gyroscope cavity is generally made of low-expansion microcrystalline glass. There are also external components such as electrodes and reflecting lenses outside it. These external components are generally made of materials such as metal and quartz. After being precisely cleaned, they are sealed together with the microcrystalline glass cavity of the laser gyroscope through a special process. After the resonance cavity is tuned, it must also be connected to a vacuum exhaust table and undergo "aging" treatment for several days to make the reflecting lens adapt to the low-pressure environment and become stable. At the same time, the microcrystalline glass cavity and other components sealed on it are also subjected to plasma cleaning to further release the non-working gas molecules attached to the surface. The extraction anode of the laser gyroscope is sealed on the cavity by heating and pressurizing indium wire to soften it. This kind of seal is very weak in resisting shear force. If the overall connection device is a rigid structure, it will cause tangential stress damage to the indium seal of the extraction anode. For a long time, the connection between the laser gyroscope and the vacuum exhaust table has been achieved through a hard glass tube of optoelectronics and a kovar alloy transition. During the connection process, a high-temperature flame generated by burning a hydrogen-oxygen mixed gas is required for sintering. When sintering, the operator also needs to blow air into the heated and softened glass tube through a glass port to control the diameter of the connection part by using the air pressure of blowing. The main drawbacks of this connection process are: blowing air from the mouth is easy to pollute the vacuum system. In addition, the use of hydrogen brings great difficulties to the safety production management of the work site and also makes the operator bear greater psychological pressure.

[0004] In recent years, great improvements have been made to the connection between the laser gyroscope and the vacuum exhaust table at home and abroad. Relying on ferrule or VCR interfaces, a metal cold connection table between the laser gyroscope and the exhaust table has been realized. These improvements have greatly reduced the use of hydrogen, but have not completely eliminated the use of hydrogen because these connection table devices still have glass materials. For example, the auxiliary getter used in the aging process is still encapsulated in a glass bulb and then connected to the metal pipeline through a kovar alloy transition. Once the auxiliary getter is used up, a hydrogen-oxygen flame sintering process needs to be used to replace the new auxiliary getter. In addition, due to the presence of glass in the system, it is inevitable that the glass will break during the long-term "aging" process, resulting in air leakage into the vacuum system, polluting the laser gyroscope and damaging the precision vacuum devices in the exhaust table. Therefore, this kind of connection table device with coexistence of glass and metal has not completely solved the above problems. Summary of the Invention

[0005] Aiming at the problems in the above-mentioned prior art, the present invention provides a non-glass device for connecting the exhaust table of a laser gyroscope, and its purpose is to completely abandon the hydrogen-oxygen flame sintering process during the connection process between the laser gyroscope and the vacuum exhaust table, and realize a complete metal cold connection, so as to improve the tolerance and service life of the laser gyroscope system in the aging and working states.

[0006] The technical solution of the present invention is as follows: A non-glass device for connecting a laser gyro to an exhaust platform, comprising a connecting device assembly, a laser gyro, a high-voltage power supply, a vacuum exhaust platform, and an activation coil. Among them, the connecting device assembly includes a first bellows, a second bellows, a partition assembly, a three-way joint, a docking pipe, a sealing joint, a storage tank, and a getter; the flange interface of the first bellows is docked and installed with the flange of the vacuum exhaust platform, thereby forming a flexible connection between the connecting device assembly and the vacuum exhaust platform; the other end of the first bellows is connected to the three-way joint through the partition assembly made of insulating non-glass material, another port of the three-way joint is connected to the second bellows, and the ferrule joint at the other end of the second bellows is connected to the extraction anode of the laser gyro, thereby forming a flexible connection between the connecting device assembly and the laser gyro; the cathode and anode of the laser gyro are electrically connected to the negative and positive poles of the high-voltage power supply respectively; in addition, the third port of the three-way joint is hermetically connected to the sealing joint through the docking pipe, and the storage tank is connected below the sealing joint. The storage tank is made of non-glass material and is a hollow flat-bottomed cylindrical tube with an open upper end. The getter is arranged on its flat bottom in the inner cavity of the storage tank; the activation coil is arranged below the flat bottom of the storage tank, and the axis of its coil is perpendicular to the flat bottom of the storage tank and coincides with the axis of the storage tank.

[0007] Further, the connecting device assembly further includes a shunt ring. The shunt ring is a ring made of a weak magnetic alloy or non-magnetic alloy material. The inner diameter of the ring has an interference fit or transitional fit relationship with the outer diameter of the storage tank. When activating the getter using the activation coil, the shunt ring is sleeved on the outer wall of the bottom of the storage tank. When the getter is already in the activated state, the shunt ring can be removed for separate heat dissipation.

[0008] Further, a vacuum gauge is provided on the pipeline between the vacuum pump system for generating negative pressure in the vacuum exhaust platform and the flange interface. The measurement accuracy order of magnitude of the vacuum gauge is less than 1×10 -6 , and the judgment criterion for the activated state of the getter is that the reading of the vacuum gauge rises by at least 2 orders of magnitude.

[0009] Further, the ferrule joint includes a ferrule nut, a front ferrule, a rear ferrule, and a main joint body. The ferrule nut is sleeved on the extraction anode of the laser gyro. The front ferrule and the rear ferrule are both conical bodies and are respectively sleeved on the extraction anode from the outside to the inside. The outer diameter of the front ferrule is larger than that of the rear ferrule. When the external thread of the main joint body is docked and installed with the internal thread of the ferrule nut, the two jointly press the front ferrule and the rear ferrule to form a sealed space, and the other end of the main joint body is hermetically fixed to the end of the second bellows.

[0010] Furthermore, the sealing joint includes a VCR joint, a VCR nut, and a sealing washer. Among them, the VCR joint is fixed to the end of the docking pipe, the VCR nut is sleeved on the VCR joint, and by screwing the VCR nut into the external thread at the end of the storage tank, the VCR joint and the end of the storage tank jointly press against both ends of the sealing washer, forming a sealed connection between the tee joint and the storage tank.

[0011] Furthermore, the partition assembly includes a ceramic tube in the middle and metal tubes at both ends. The two metal tubes are fixed to both ends of the ceramic tube by brazing. One of the metal tubes is welded and fixed to a connecting pipe, and the other end of the connecting pipe is connected to the tee joint.

[0012] Furthermore, the getter is a zirconium-aluminum getter. When activating the getter, a power of 950 - 1100W is used to drive the activation coil to generate electromagnetic waves with a frequency of 1.5 ± 0.1 MHz; the activation coil is turned on at intervals, with each turn-on time ≤ 25s, and the total duration of multiple turn-ons of the activation coil to keep the getter at the activation temperature is 5 - 15 minutes, so that the getter enters a fully activated state and performs the gas absorption function.

[0013] Furthermore, the number of turns of the activation coil is 2 - 4 turns. When the activation coil is working, the distance between its position on the horizontal plane and the bottom surface of the getter is ≤ 50mm.

[0014] Furthermore, the getter is in a disc shape, the difference between the inner diameter of the storage tank and the outer diameter of the getter is 0 - 3mm, and the storage tank is made of 304 austenitic non-magnetic stainless steel or non-magnetic alloy material.

[0015] Furthermore, convex-shaped flow dividing edges are provided on the outer wall of the flow dividing ring, and the serpentine path of the flow dividing edges is arranged around the axis of the flow dividing ring for one week.

[0016] The beneficial effects of the present invention are:

[0017] 1. The present invention uses the design of a storage tank made of non - glass material, a partition component, and a bellows connection structure, completely abandoning the use of glass materials, achieving a metal cold connection between the laser gyro and the vacuum exhaust table. It is convenient for disassembly and assembly, has good sealing performance, completely eliminates the safety hazards brought by the use of hydrogen, and there is no need to worry about the pollution and damage of the vacuum system and the laser gyro caused by the rupture of the glass tube. At the same time, the getter in the storage tank can continuously generate an air - absorbing effect after various vacuum pumps in the vacuum exhaust system stop working, adsorbing the impurity gases generated during the aging process of the laser gyro. Moreover, by using the flat - bottom structure of the storage tank, the activation coil can be calibrated from the outside, effectively improving the electromagnetic activation efficiency and the purity of the working gas. The installation and replacement of the getter also achieve fire - free operation, which is safe, convenient, and has good airtightness, greatly ensuring the accuracy, lifespan, and stability of the operation of the laser gyro equipment.

[0018] 2. The bellows flexible connection of the present invention can effectively avoid the stress damage caused by rigid connection to the laser gyro and its indium - sealed structure of the extraction anode. At the same time, the VCR joint and the ferrule joint are used to achieve the flexible disassembly, assembly, and tight sealing of the air - absorbing device assembly. The connection and disassembly efficiency of the connection device assembly, the laser gyro, and the vacuum exhaust table is significantly improved compared with glass sintering, and it has good practical value in the industry.

[0019] 3. Through the design of the shunt ring sleeved on the outer wall of the bottom of the storage tank, the present invention utilizes the skin effect of high - frequency alternating current to make a large number of induced eddy currents of the activation coil concentrate on the outer wall of the shunt ring and the thin surface of the bottom of the storage tank respectively in addition to activating the getter, thereby effectively sharing the influence of the eddy - current thermal effect on the side wall of the storage tank, reducing the degree of thermal deformation of the storage tank, and preventing heat from being conducted through the metal connecting piece to interfere with the laser gyro, effectively improving the measurement accuracy of the laser gyro. At the same time, the parallel coupling of the outer - wall eddy current is formed by the shunt ridges arranged in a serpentine pattern on the outer wall of the shunt ring, thereby effectively suppressing the concentration degree of the induced eddy current on the outer wall of the shunt ring, further reducing the degree of thermal deformation of the shunt ring itself, so as to ensure the alignment accuracy and activation efficiency of the activation coil to the getter, and improve the anti - interference ability of the overall device to thermal deformation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is the schematic assembly structure diagram of the present invention;

[0021] Figure 2 is the schematic structure diagram of the connection device assembly in the present invention;

[0022] Figure 3 is the partial structure explosion diagram of the partition component in the present invention;

[0023] Figure 4 is the relevant structure explosion diagram of the ferrule joint in the present invention;

[0024] Figure 5Explosion diagram of the relevant structure of the sealing joint in the present invention;

[0025] Figure 6 Schematic diagram of the working state of the activation coil in the present invention;

[0026] Figure 7 Schematic diagram of the installation structure of the shunt ring and the storage tank in the present invention;

[0027] Figure 8 Schematic diagram of the eddy current direction of the shunt ridge in the present invention;

[0028] Figure 9 Schematic diagram of the finite element analysis of the storage tank under the eddy current thermal effect in the present invention;

[0029] Figure 10 Schematic diagram of the finite element analysis of the storage tank under the eddy current thermal effect after installing the shunt ring in the present invention.

[0030] In the figure: 1 - connecting device assembly, 11 - bellows one, 111 - flange interface, 12 - bellows two, 121 - ferrule joint, 121a - ferrule nut, 121b - front ferrule, 121c - rear ferrule, 121d - main joint body, 13 - partition assembly, 131 - ceramic tube, 132 - metal tube, 133 - connecting tube, 14 - three-way joint, 15 - docking tube, 16 - sealing joint, 161 - VCR joint, 162 - VCR nut, 163 - sealing washer, 17 - storage tank, 18 - getter, 19 - shunt ring, 19a - shunt ridge, 2 - laser gyroscope, 21 - extraction anode, 22 - cathode, 23 - anode, 3 - high-voltage power supply, 4 - vacuum exhaust station, 41 - vacuum pump system, 42 - vacuum gauge, 5 - activation coil. Detailed implementation manners

[0031] The present invention will be further described in detail below with reference to the accompanying drawings of the specification and embodiments.

[0032] Embodiment 1

[0033] As Figure 1-6As shown in the figure, a non-glass device for connecting a laser gyro 2 to an exhaust table includes a connecting device assembly 1, a laser gyro 2, a high-voltage power supply 3, a vacuum exhaust table 4, and an activation coil 5. Among them, the connecting device assembly 1 includes a first bellows 11, a second bellows 12, a partition assembly 13, a three-way joint 14, a docking pipe 15, a sealing joint 16, a storage tank 17, and a getter 18; the flange interface 111 of the first bellows 11 is butt-mounted with the flange of the vacuum exhaust table 4, thereby forming a flexible connection between the connecting device assembly 1 and the vacuum exhaust table 4. A vacuum gauge 42 is provided on the pipeline between the vacuum pump system 41 for generating negative pressure in the vacuum exhaust table 4 and the flange interface 111. The measurement accuracy order of magnitude of the vacuum gauge 42 is 1×10 -7; The other end of the bellows 11 is connected to the three-way joint 14 through the partition assembly 13. The partition assembly 13 includes a ceramic tube 131 in the middle and metal tubes 132 fixed at both ends thereof by brazing. One of the metal tubes 132 is welded and fixed to a connecting tube 133, and the other end of the connecting tube 133 is connected to the three-way joint 14; the other port of the three-way joint 14 is connected to the bellows 12. The other end of the bellows 12, the ferrule joint 121, is connected to the extraction anode 21 of the laser gyro 2, thereby forming a flexible connection between the connection device assembly 1 and the laser gyro 2. The ferrule joint 121 includes a ferrule nut 121a, a front ferrule 121b, a rear ferrule 121c, and a main joint body 121d. The ferrule nut 121a is sleeved on the extraction anode 21 of the laser gyro 2. The front ferrule 121b and the rear ferrule 121c are both conical bodies and are respectively sleeved on the extraction anode 21 from the outside to the inside. The outer diameter of the front ferrule 121b is larger than that of the rear ferrule 121c. When the external thread of the main joint body 121d is butt-joined with the internal thread of the ferrule nut 121a, the two jointly press the front ferrule 121b and the rear ferrule 121c to form a sealed space, and the other end of the main joint body 121d is hermetically fixed to the end of the bellows 12; the cathode 22 and the anode 23 of the laser gyro 2 are respectively electrically connected to the negative electrode and the positive electrode of the high-voltage power supply 3; in addition, the third port of the three-way joint 14 is hermetically connected to the sealing joint 16 through the docking tube 15. The sealing joint 16 includes a VCR joint 161, a VCR nut 162, and a sealing gasket 163. The VCR joint 161 is fixed to the end of the docking tube 15. The VCR nut 162 is sleeved at the VCR joint 161. By screwing the VCR nut 162 into the external thread at the end of the storage tank 17, the VCR joint 161 and the end of the storage tank 17 jointly abut against both ends of the sealing gasket 163 to form a sealed connection between the three-way joint 14 and the storage tank 17; the storage tank 17 is made of 304 austenitic non-magnetic stainless steel and is a hollow flat-bottomed circular cylinder with an open upper end. An getter 18 placed on its flat bottom is provided in the inner cavity of the storage tank 17. The getter 18 is a round cake-shaped zirconium-aluminum getter 18, and its outer diameter is 2 mm smaller than the inner diameter of the storage tank 17; the activation coil 5 is arranged below the flat bottom of the storage tank 17, and the axis of its coil is perpendicular to the flat bottom of the storage tank 17 and coincides with the axis of the storage tank 17.

[0034] The working steps of this embodiment are as follows:

[0035] Step 1: Before the getter 18 is put into the storage tank 17, its threaded joint needs to be removed. Then, with the flat bottom of the getter 18 facing down, it is slid along the inner wall of the storage tank 17 to the bottom plane so that their planes are in contact. After that, each component is connected and installed as described above, and the tightness of the seals at each docking point such as the ferrule joint 121 and the sealing joint 16 is inspected to ensure the airtight performance of the device.

[0036] Step 2: Start the vacuum pump system 41 to evacuate the air and maintain a low-pressure state for the system operation. Then start the high-voltage power supply 3 to discharge and glow between the cathode 22 and the anode 23. The glow voltage is as high as several thousand volts. After the current stabilizes, maintain the voltage at several hundred volts. Since the extraction anode 21 is both an electrode of the ring laser gyro 2 and a connection port between the ring laser gyro 2 and the vacuum exhaust table 4, the insulation is ensured through the ceramic tube 131 of the partition component 13 in the connection device assembly 1. An insulation block is formed between the positive pole of the high-voltage power supply 3 and the metal tube 132 path of the vacuum exhaust table 4 to ensure the safety of the equipment and operators. At the same time, the flexible connections of the bellows I 11 and the bellows II 12 effectively prevent stress damage to the indium seal structure of the extraction anode 21.

[0037] Step 3: Align the axis of the activation coil 5 with the center of the circular bottom surface of the storage tank 17 and ensure that the distance between the center of the cross-section of the activation coil 5 and the bottom surface of the storage tank 17 is 15 mm. Since the difference between the inner diameter of the storage tank 17 and the outer diameter of the disc-shaped getter 18 in the designed dimensions is only 2 mm, visual calibration does not need to rely on the previous glass shell. As long as the axis of the activation coil 5 is aligned with the axis of the storage tank 17, it can ensure alignment with the getter 18. Then, drive the activation coil 5 with 4 turns around at a power of 1000 W to generate an electromagnetic wave with a frequency of 1.5 MHz. When starting for the first time, after 25 s, pause the coil power supply. After that, turn on the activation coil 5 multiple times at certain intervals. The time for each turn-on of the activation coil 5 should be such that the getter 18 is maintained at a constant activation temperature. Continue this intermittent operation for 5 - 12 min. If during this process, the order of magnitude of the reading of the vacuum gauge 42 rises from 10 -7 to 10 -5 , it can be ensured that the getter 18 has entered the stimulated gas absorption state, and then turn off the coil power supply. Since activation uses electromagnetic induction heating, high-frequency alternating current is passed through the coil to generate a high-frequency electromagnetic field, causing the magnetic induction lines to pass through the disc-shaped getter 18, and then eddy currents are generated in the getter 18, triggering a thermal effect, thereby reaching a high temperature, activating the gas-absorbing substance and adsorbing the impurity gases in the inner cavity of the overall device. At the same time, since the storage tank 17 is made of metal, a certain degree of eddy current effect will also occur and cause heating, such as Figure 7As shown in the figure, the above parameters are simulated using the multi-physics interface in the finite element analysis software COMSOL Multiphysics. It is calculated that when the activation coil 5 lasts for 25 s, the bottom surface temperature of the storage tank 17 is 350 °C, and the side wall temperature near the bottom end is about 200 °C. Since the deformation temperature range of the stainless steel material is 900-1150 °C, it can ensure that the thermal deformation degree of the storage tank 17 meets the requirements of the use range, and then maintain the alignment of the activation coil 5. At the same time, the above parameters and structure have withstood the test of production practice in actual production, have good airtightness, extremely low leakage rate, and show high reliability during high-temperature baking, ensuring the measurement accuracy of the laser gyro 2.

[0038] Step 4: Regularly activate the getter 18 according to the operation described in Step 3. During the regular heating and degassing process, a large number of gas molecules are released (the reading of the vacuum gauge 42 increases by two orders of magnitude), indicating that it serves the purpose of absorbing miscellaneous gases during the aging process of the laser gyro 2 and improving the service life of the long-term operation of the laser gyro 2.

[0039] Embodiment 2

[0040] The difference between this embodiment and Embodiment 1 is that the connecting device assembly 1 further includes a shunt ring 19. The shunt ring 19 is a ring-shaped body made of non-magnetic alloy material, and its inner ring diameter has an interference fit relationship with the outer diameter of the storage tank 17.

[0041] As Figure 7 shown, when activating the getter 18 using the activation coil 5, the shunt ring 19 is sleeved on the outer wall of the bottom of the storage tank 17, so that the bottom surface of the shunt ring 19 is flush with the bottom surface of the storage tank 17. At this time, start the activation coil 5 according to the same parameters and methods described in Step 3 of Embodiment 1. Using the skin effect of high-frequency alternating current, a large number of induced eddy currents of the activation coil 5 are concentrated on the outer wall of the shunt ring 19 and the thin surface of the bottom of the storage tank 17 respectively in addition to activating the getter 18, thereby effectively sharing the influence of the eddy current thermal effect on the side wall of the storage tank 17. As Figure 10 shown, the storage tank 17 equipped with the shunt ring 19 is simulated using the multi-physics interface in the finite element analysis software COMSOL Multiphysics. It is calculated that when the activation coil 5 lasts for 25 s, the bottom surface temperature of the storage tank 17 is 350 °C, and the side wall temperature near the bottom end is about 50 °C. Compared with the bottom side wall temperature (200 °C) measured in Embodiment 1, there is an obvious decrease, and it can be seen from the following table that installing the shunt ring 19 has an obvious effect on reducing the side wall temperature of the storage tank 17.

[0042] Inductive temperature \ Installation structure Separate storage tank( Figure 9 ) Storage tank + flow splitting ring( Figure 10 ) Bottom surface temperature of storage tank (℃) 350 350 Bottom side wall temperature of storage tank (℃) 200 50 Middle side wall temperature of storage tank (℃) 100 25

[0043] From Figure 10It can be clearly seen that the side wall of the storage tank 17 is hardly affected by the eddy current thermal effect. The heat generated by induction heating is mainly concentrated on the bottom surface of the storage tank 17 and the getter 18 placed on the bottom surface, thereby effectively reducing the degree of thermal deformation in the axial direction of the storage tank 17 and preventing the thermal interference caused by the heat conduction through the metal connecting piece to the laser gyro 2, and improving the measurement accuracy of the laser gyro 2 and the calibration accuracy of the activation coil 5.

[0044] From Figure 10 And Figure 9 By comparison and analysis, although the flow dividing ring 19 has a greater cooling effect on the side wall of the storage tank 17, the temperature of the bottom surface of the storage tank 17 has no obvious change. Therefore, it can be judged that the flow dividing ring 19 has a lower interference degree on the electromagnetic field in the central part of the activation coil 5. Therefore, the high-frequency electromagnetic field in the central annular part of the activation coil 5 can normally pass through the getter 18 above the bottom surface of the storage tank 17, so as to normally implement the activation operation.

[0045] When the intermittent activation operation lasting for 5 - 12 minutes is completed, the reading of the vacuum gauge 42 changes significantly, indicating that the getter 18 reaches the activation state. At this time, turn off the power supply of the activation coil 5 and let it stand for a while to make the residual high temperature on the bottom surface of the storage tank 17 transfer upward to the flow dividing ring 19, and then use tools to remove the flow dividing ring 19 to reduce the isolated heat dissipation alone, so as to ensure that most of the induced heat energy is absorbed by the flow dividing ring 19, reduce the influence of thermal interference on the overall device, and improve the measurement accuracy of the laser gyro 2.

[0046] Embodiment 3

[0047] The difference between this embodiment and Embodiment 1 is that: the connecting device assembly 1 further includes a flow dividing ring 19. At the same time, the difference between this embodiment and Embodiment 2 is that: the outer wall of the flow dividing ring 19 is provided with convex flow dividing edges 19a distributed in a serpentine path, and the serpentine path of the flow dividing edges 19a is arranged around the axis of the flow dividing ring 19 for one week.

[0048] As Figure 7 shown, the flow dividing ring 19 with the flow dividing edges 19a is sleeved on the outer wall of the bottom of the storage tank 17 so that the bottom surface of the flow dividing ring 19 is flush with the bottom surface of the storage tank 17, and then the activation coil 5 is started according to the same parameters and methods described in Embodiment 2.

[0049] As Figure 8 shown, when the excitation coil generates a high-frequency electromagnetic field acting on the flow dividing ring 19 to generate high-frequency induced eddy currents, due to the skin effect of high-frequency currents, it will be concentrated on the thin sheet on the surface of the conductor, and the induced eddy currents will propagate along the serpentine path of the flow dividing edges 19a. At this time, the current directions on any two adjacent edges of the flow dividing edges 19a are opposite, thereby dividing into multiple magnetic field regions with adjacent opposite directions (as Figure 8The magnetic field direction where the symbol "×" is located points to the axis of the shunt edge 19a, and the magnetic field direction where the symbol "·" is located deviates from the axis of the shunt edge 19a). Therefore, when the magnitude of the eddy current changes with the alternating electromagnetic field, Figure 8 the edge current in each magnetic field region in Figure 8 will be inhibited by the induced current generated by the adjacent reverse magnetic field. Similarly, through the parallel coupling between multiple edges, the shunt edge 19a can be equivalently regarded as a ring-shaped filter inductor as a whole, thereby reducing the current intensity of the high-frequency eddy current on the surface of the shunt ring 19. At the same time, the shunt edge 19a can play a role in assisting heat dissipation. Through the above method, the degree of thermal deformation of the shunt ring 19 itself is further reduced, so as to ensure the alignment accuracy and activation efficiency of the activation coil 5 to the getter 18, and improve the anti-interference ability of the overall device to thermal deformation.

[0050] The above-described embodiments are only preferred embodiments of the present invention and do not constitute a formal limitation on the present invention. It should be understood that for those skilled in the art, other modifications, changes and equivalent substitutions can also be made by using the features of the claims of the present invention, and these should all fall within the protection scope of the present invention.

Claims

1. A non - glass device for connecting a laser gyro to an exhaust table, comprising a connecting device assembly, a laser gyro, a high - voltage power supply, a vacuum exhaust table, and an activation coil. Characterized in that: The connecting device assembly includes a first bellows, a second bellows, a partition component, a three - way joint, a butt - joint pipe, a sealing joint, a storage tank, and a getter. The flange interface of the first bellows is butt - connected and installed with the flange of the vacuum exhaust table, thereby forming a flexible connection between the connecting device assembly and the vacuum exhaust table. The other end of the first bellows is connected to the three - way joint through the partition component made of insulating non - glass material. The other port of the three - way joint is connected to the second bellows. The other end of the second bellows is connected to the extraction anode of the laser gyro through a ferrule joint, thereby forming a flexible connection between the connecting device assembly and the laser gyro. The cathode and anode of the laser gyro are electrically connected to the negative and positive poles of the high - voltage power supply respectively. In addition, the third port of the three - way joint is hermetically connected to the sealing joint through the butt - joint pipe. The storage tank is connected below the sealing joint. The storage tank is made of non - glass material and is a hollow flat - bottomed circular cylinder with an open upper end. The getter is arranged on its flat bottom in the inner cavity of the storage tank. The activation coil is arranged below the flat bottom of the storage tank. The axis of its coil is perpendicular to the flat bottom of the storage tank and coincides with the axis of the storage tank. The connecting device assembly further includes a shunt ring. The shunt ring is a ring made of a weak - magnetic alloy or non - magnetic alloy material. The inner diameter of its ring has an interference fit or transitional fit relationship with the outer diameter of the storage tank. When activating the getter using the activation coil, the shunt ring is sleeved and installed on the outer wall of the bottom of the storage tank. When the getter is already in an activated state, the shunt ring can be removed for separate heat dissipation. The outer wall of the shunt ring is provided with convex shunt ribs distributed in a serpentine path. The serpentine path of the shunt ribs is arranged around the axis of the shunt ring for one week.

2. A non - glass device for connecting a laser gyro to an exhaust table according to claim 1, Characterized in that: A vacuum gauge is provided on the pipeline between the vacuum pump system for generating negative pressure in the vacuum exhaust table and the flange interface, and the order of magnitude of the measurement accuracy of the vacuum gauge is less than 1×10 -6 . The judgment criterion for the activation state of the getter is that the reading of the vacuum gauge rises by at least 2 orders of magnitude.

3. A non - glass device for connecting a laser gyro to an exhaust table according to claim 1, Characterized in that: The ferrule joint includes a ferrule nut, a front ferrule, a rear ferrule, and a main joint body. The ferrule nut is sleeved on the extraction anode of the laser gyro. The front ferrule and the rear ferrule are both conical bodies and are respectively sleeved on the extraction anode from the outside to the inside. The outer diameter of the front ferrule is larger than that of the rear ferrule. When the external thread of the main joint body is butt - connected and installed with the internal thread of the ferrule nut, the two jointly press the front ferrule and the rear ferrule to form a sealed space. The other end of the main joint body is hermetically fixed to the end of the second bellows.

4. A non - glass device for connecting a laser gyro to an exhaust table according to claim 1, Characterized in that: The sealing joint includes a VCR joint, a VCR nut, and a sealing washer. The VCR joint is fixed to the end of the butt joint pipe. The VCR nut is sleeved on the VCR joint. By screwing the VCR nut into the external thread at the end of the storage tank, the VCR joint and the end of the storage tank jointly press against both ends of the sealing washer, forming a sealed connection between the tee joint and the storage tank.

5. A non-glass device for connecting an exhaust platform of a ring laser gyroscope according to claim 1, characterized in that: The partition assembly includes a ceramic tube in the middle and metal tubes at both ends. The two metal tubes are fixed to both ends of the ceramic tube by brazing. One of the metal tubes is welded and fixed to a connecting pipe, and the other end of the connecting pipe is connected to the tee joint.

6. A non-glass device for connecting an exhaust platform of a ring laser gyroscope according to claim 1, characterized in that: The getter is a zirconium-aluminum getter. When activating the getter, a power of 950-1100 W is used to drive the activation coil to generate an electromagnetic wave with a frequency of 1.5±0.1 MHz; the activation coil is turned on in an intermittent manner, and the on-time each time is ≤25 s. The total duration of repeatedly turning on the activation coil to keep the getter at the activation temperature is 5-15 min, so that the getter enters a fully activated state and performs the gas absorption function.

7. A non-glass device for connecting an exhaust platform of a ring laser gyroscope according to claim 1, characterized in that: The number of turns of the activation coil is 2-4 turns. When the activation coil is working, the distance between its set position on the horizontal plane and the bottom surface of the getter is ≤50 mm.

8. A non-glass device for connecting an exhaust platform of a ring laser gyroscope according to claim 1, characterized in that: The getter is in a disc shape. The difference between the inner diameter of the storage tank and the outer diameter of the getter is 0-3 mm. The storage tank is made of 304 austenitic non-magnetic stainless steel or non-magnetic alloy material.

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