A cryostat based on low temperature self-regulation

Abstract

The application discloses a low-temperature thermostat based on low-temperature self-adjustment, which comprises a thermostat bottom plate, a cold mass support unit and a support assembly, wherein the cold mass support unit is slidably fixed on the top of the thermostat bottom plate through the support assembly, and the cold mass support unit is pre-offset installed relative to the thermostat bottom plate at normal temperature; and the pre-offset amount of the cold mass support unit is the cold shrinkage amount of the material of the cold mass support unit at a low-temperature state. In the application, the cold mass support unit is pre-offset installed at normal temperature, so that the whole low-temperature thermostat returns to the center line position when cold shrinking at a low temperature, thereby ensuring that the center line at the low temperature is not offset and ensuring that the low-temperature collimation is ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of low-temperature superconducting accelerator, more particularly to a low-temperature thermostat based on low-temperature self-adjustment. BACKGROUND

[0002] The low-temperature thermostat is the most important component of the superconducting particle accelerator device, which provides liquid helium and mechanical support for the superconducting cavity and superconducting magnet, realizes and maintains the temperature and pressure environment required for the normal operation of the superconducting element, and forms a thermal shield and thermal isolation to reduce the overall thermal load of the system. The performance will directly determine the investment and operating cost of the entire low-temperature system of the accelerator.

[0003] The cold mass of the thermostat is composed of a plurality of superconducting cavities and superconducting magnets in series. In order to ensure the particle acceleration performance, the relative positions of each superconducting cavity and superconducting magnet must be fixed. The position of the cold mass can be aligned at room temperature, but the material will have a cold shrinkage phenomenon at low temperature, and the cold shrinkage amount of different materials is not the same. The low-temperature alignment problem of the cold mass is the key to the performance of the thermostat.

[0004] The existing patent document with the patent number CN 205175896 U discloses an adjustable coupling connector of a spectrometer and a low-temperature thermostat. The adjustable coupling connector of the spectrometer and the low-temperature thermostat includes a bracket, the bracket includes an upper support plate, a lower support plate and a support column, a cavity for placing a sample cup of the spectrometer is formed between the upper support plate and the lower support plate; the lower support plate is provided with a base, the upper end surface of the base is provided with a groove for placing the sample cup of the spectrometer with the opening facing upward; the upper support plate is provided with a through hole penetrating through both ends of the surface and a reserved observation hole; the upper support plate is provided with a direction fine adjustment device around the through hole, the direction fine adjustment device is used for clamping and adjusting the position of the cold head in the cavity; the bracket is provided with a backstop plate on the side, the top of the backstop plate is connected with the upper support plate, the bottom of the backstop plate is connected with the lower support plate, and the connection between the bottom of the backstop plate and the lower support plate is provided with an angle link; the edge of the through hole is provided with a flexible material layer.

[0005] However, the low-temperature thermostat has a cold shrinkage phenomenon at low temperature, and the cold shrinkage amount of different materials is not the same, which cannot ensure the alignment at low temperature. SUMMARY

[0006] The technical problem to be solved by the present application is how to ensure the alignment of the cold mass support bracket at low temperature.

[0007] The present application solves the above technical problems through the following technical means: a low-temperature thermostat based on low-temperature self-adjustment, including a thermostat bottom plate, a cold mass support unit and a support assembly, the cold mass support unit is slidably fixed on the top of the thermostat bottom plate through the support assembly, the cold mass support unit is pre-offset installed relative to the thermostat bottom plate at room temperature, and the pre-offset amount of the cold mass support unit is the cold shrinkage amount of the material at low temperature.

[0008] By pre-offsetting the cold mass support unit at room temperature, the entire cryostat can return to the centerline position when it is cold contracted at low temperature, thereby ensuring that the centerline at low temperature is not offset and ensuring collimation at low temperature.

[0009] As a preferred technical solution, the cold mass support unit comprises a cold mass support part, a plurality of series-connected superconducting cavities and superconducting magnets are mounted on the cold mass support part, the cold mass support part comprises two symmetrically distributed cold mass supports, and the center line of the connecting pipeline connecting the plurality of series-connected superconducting cavities and superconducting magnets forms a beam center.

[0010] As a preferred technical solution, the support assembly comprises fixed supports and sliding supports, the cold mass support part is fixedly connected to the cryostat bottom plate through a fixed support at the middle of each side, and the free end of the cold mass support is slidingly fixed to the cryostat bottom plate through two sliding supports, the connecting line between the two fixed supports coincides with the vertical projection of the beam center axis, and the free end of the cold mass support slides towards the fixed support of the cold mass support part at low temperature.

[0011] By arranging the fixed supports at the centerline position and arranging the sliding supports on both sides, the sliding support points will move towards the fixed support points as the temperature cools down, thereby ensuring that the centerline does not deviate.

[0012] As a preferred technical solution, the two cold mass supports are a left cold mass support and a right cold mass support, respectively, the left end bottom of the left cold mass support and the right end bottom of the right cold mass support are fixedly connected to the cryostat bottom plate through fixed supports, and the right end bottom of the left cold mass support and the left end bottom of the right cold mass support are slidingly fixed to the cryostat bottom plate through two sliding supports.

[0013] As a preferred technical solution, one end of the superconducting cavity is fixedly connected to the cold mass support, and the other end is movably connected to the cold mass support, one end of the superconducting magnet is fixedly connected to the cold mass support, and the other end is movably connected to the cold mass support, the adjacent superconducting cavities are connected by a telescopic bellows, and the two ends of the superconducting magnet are connected to the superconducting cavities through the telescopic bellows.

[0014] By arranging the telescopic bellows, the movement of the cold mass support in the X and Y directions when it is cold contracted can be ensured, and by arranging the superconducting cavity and the superconducting magnet to be fixedly connected to the cold mass support at one end and movably connected at the other end, the cold contraction of the superconducting cavity, the superconducting magnet and their connecting parts at low temperature can be ensured.

[0015] As a preferred technical scheme, the superconducting cavity is fixedly connected with first and second connecting plates at two ends respectively, the cold mass support is fixed with connecting pieces adapted to the first and second connecting plates at two ends connected with the superconducting cavity, the connecting pieces comprise first and second connecting tables, the first connecting plate is slidably connected with the first connecting table through a supporting sliding mechanism, and the second connecting plate is connected and fastened with the second connecting table through bolts.

[0016] As a preferred technical scheme, the second connecting plate is a rectangular plate, two waist holes are formed in the top of one end of the second connecting plate respectively, a guide column is fixed on the top of the second connecting table, the waist holes are adapted to the guide column, and the bolts are located at the center of the line connecting the two waist holes.

[0017] As a preferred technical scheme, the supporting sliding mechanism comprises a lower sliding plate and a lower fixed plate, the first connecting plate is a U-shaped plate, the large end surface of the first connecting plate is fixedly connected with the superconducting cavity, the two small end surfaces of the first connecting plate are each formed with a mounting hole adapted to the lower sliding plate, the lower sliding plate is fixedly connected in the mounting hole, the lower fixed plate is fixedly embedded on the top of the cold mass support, the lower sliding plate is slidably connected with the lower fixed plate through a plurality of balls, and the radius of the balls is greater than the sum of the cold shrinkage amounts of the first connecting plate, the superconducting cavity and the second connecting plate at low temperature.

[0018] Through the arrangement of the lower sliding plate, the lower fixed plate and the balls therebetween, the sliding support between the superconducting cavity and the cold mass support can be realized, and by setting the radius of the balls to be greater than the sum of the cold shrinkage amounts of the first connecting plate, the superconducting cavity and the second connecting plate at low temperature, it can be ensured that the first connecting plate will not be separated from the first connecting table during cold shrinkage, and automatic reset can be realized at room temperature.

[0019] As a preferred technical scheme, the superconducting magnet is fixedly connected with third and fourth connecting plates at two ends respectively, the top of the cold mass support is fixed with third and fourth connecting tables adapted to the third and fourth connecting plates, the fourth connecting plate is fixedly connected with the fourth connecting table, and the third connecting plate is slidably connected with the third connecting table through a supporting sliding mechanism.

[0020] As a preferred technical scheme, the sliding support comprises a sliding support cylinder, a low-temperature end second inner flange, a second heat sink outer flange, a room-temperature end second inner flange, an upper layer sliding rail, a sliding block, a second cold screen support and a bottom layer sliding rail, the bottom plate of the thermostat is fixedly connected with a plurality of bottom layer sliding rails on the top, the bottom layer sliding rails are slidably connected with sliding blocks, the sliding blocks are slidably connected with upper layer sliding rails on the top, the vertical projections of the bottom layer sliding rails and the upper layer sliding rails form a cross-shaped structure, the upper layer sliding rails are fixedly connected with the sliding support cylinder through the room-temperature end second inner flange on the top, the low-temperature end second inner flange is in interference fit with the inner wall of the top of the sliding support cylinder, and the sliding support cylinder is fixedly connected with the cold mass support through the low-temperature end second inner flange.

[0021] As a preferred technical solution, the cold mass support is externally provided with a cold shield, the outer wall of the sliding support cylinder is fixedly connected with a second heat sink outer flange, and the second heat sink outer flange is fixed with the cold shield through a second cold shield support.

[0022] As a preferred technical solution, the sliding support further comprises a low-temperature end second outer flange, a second heat sink inner flange and a room-temperature end second outer flange, the low-temperature end second outer flange is fixedly arranged on the outer wall of the top of the sliding support cylinder, the second heat sink inner flange is fixedly arranged on the inner wall of the sliding support cylinder, and the plane where the second heat sink inner flange is located is located on the same plane as the plane where the second heat sink outer flange is located, and the room-temperature end second outer flange is fixedly connected with the outer wall of the bottom of the sliding support cylinder.

[0023] As a preferred technical solution, the top of the thermostat bottom plate is fixed with a vacuum chamber, a vacuum cavity is formed in the vacuum chamber, the cold shield is located in the vacuum cavity, a vacuum pipeline is further arranged in the cold shield, and the cold mass support unit further comprises a low-temperature pipeline mounting support, which is fixedly arranged on the top of the cold mass support and provides mounting support for the low-temperature pipeline.

[0024] As a preferred technical solution, the low-temperature pipeline comprises a main pipe and a branch pipe, the main pipe comprises a vertical section and a horizontal section, the vertical section of the main pipe is provided with an expansion bellows, the bottom of the horizontal section of the main pipe is connected with a plurality of branch pipes, the top of the superconducting cavity and the superconducting magnet is respectively provided with a connecting pipe, and the branch pipes are respectively connected with the connecting pipes through the expansion bellows, which can ensure the movement during cold shrinkage, and the horizontal installation is conducive to compensating for the large cold shrinkage displacement in the beam direction, thereby maintaining the stability of the pipeline.

[0025] As a preferred technical solution, valves are arranged at both ends of the connecting pipeline, the connecting pipeline is in a beam vacuum state, a connecting port is arranged on the vacuum chamber, the connecting port is rotatably connected with a transmission rod, the transmission rod is in transmission connection with the expansion ends of the valves through a cross universal joint, and the movement of the valve core in the valve can be realized by rotating the transmission rod, so as to realize the closing or opening of the beam vacuum.

[0026] As a preferred technical solution, the expansion bellows connecting the branch pipes and the connecting pipes is horizontally installed.

[0027] The advantages of the present application are as follows:

[0028] (1) In the present application, the cold mass support unit is pre-offset installed at room temperature, so that the entire low-temperature thermostat returns to the centerline position when cold shrinking at low temperature, thereby ensuring that the centerline at low temperature is not offset and ensuring the collimation at low temperature.

[0029] (2) In the application, the telescopic corrugated pipe is arranged to ensure the movement of the cold mass support in the X direction and the Y direction during cold shrinking, and the superconducting cavity and the superconducting magnet are fixed at one end of the superconducting cavity and the superconducting magnet and movably connected at the other end, so as to ensure the cold shrinking of the superconducting cavity, the superconducting magnet and the connecting parts thereof under low temperature.

[0030] (3) In the application, the lower sliding plate, the lower fixed plate and the ball therebetween are arranged to realize the sliding support between the superconducting cavity and the cold mass support, the radius of the ball is greater than the sum of the cold shrinking amount of the first connecting plate, the superconducting cavity and the second connecting plate under low temperature, so as to ensure that the first connecting plate will not be separated from the first connecting table during cold shrinking, and the automatic reset can be realized under normal temperature.

[0031] (4) In the application, the telescopic corrugated pipe is arranged to ensure the movement during cold shrinking, and the horizontal installation is conducive to compensating for the large cold shrinking displacement of the beam direction, so as to maintain the stability of the pipeline. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 A schematic diagram of the overall structure of a low-temperature thermostat based on low-temperature self-adjustment is provided for the embodiments of the application.

[0033] Figure 2 A schematic diagram of the beam center structure of a low-temperature thermostat based on low-temperature self-adjustment is provided for the embodiments of the application.

[0034] Figure 3 A schematic diagram of the cold mass support structure of a low-temperature thermostat based on low-temperature self-adjustment is provided for the embodiments of the application.

[0035] Figure 4 A schematic diagram of the support assembly structure of a low-temperature thermostat based on low-temperature self-adjustment is provided for the embodiments of the application.

[0036] Figure 5 A schematic diagram of the cold screen structure of a low-temperature thermostat based on low-temperature self-adjustment is provided for the embodiments of the application.

[0037] Figure 6 A schematic diagram of the valve structure of a low-temperature thermostat based on low-temperature self-adjustment is provided for the embodiments of the application.

[0038] Figure 7 A schematic diagram of the support assembly top view structure of a low-temperature thermostat based on low-temperature self-adjustment is provided for the embodiments of the application.

[0039] Figure 8 A schematic diagram of the support assembly three-dimensional structure of a low-temperature thermostat based on low-temperature self-adjustment is provided for the embodiments of the application.

[0040] Figure 9A first cold screen support structure schematic diagram of a low-temperature thermostat based on low-temperature self-regulation is provided for the embodiment of the present application.

[0041] Figure 10 A fixed support structure schematic diagram of a low-temperature thermostat based on low-temperature self-regulation is provided for the embodiment of the present application.

[0042] Figure 11 A second cold screen support structure schematic diagram of a low-temperature thermostat based on low-temperature self-regulation is provided for the embodiment of the present application. Figure 10 A B-B cross-sectional structure schematic diagram of the low-temperature thermostat based on low-temperature self-regulation.

[0043] Figure 12 A sliding support structure schematic diagram of a low-temperature thermostat based on low-temperature self-regulation is provided for the embodiment of the present application.

[0044] Figure 13 A sliding support structure schematic diagram of a low-temperature thermostat based on low-temperature self-regulation is provided for the embodiment of the present application.

[0045] Figure 14 A A-A cross-sectional structure schematic diagram of the low-temperature thermostat based on low-temperature self-regulation. Figure 13

[0046] Figure 15 A cold mass support overhead structure schematic diagram of a low-temperature thermostat based on low-temperature self-regulation is provided for the embodiment of the present application.

[0047] Figure 16 A mass support overhead side view structure schematic diagram of a low-temperature thermostat based on low-temperature self-regulation is provided for the embodiment of the present application.

[0048] Figure 17 A low-temperature pipeline mounting support structure schematic diagram of a low-temperature thermostat based on low-temperature self-regulation is provided for the embodiment of the present application.

[0049] Figure 18 A superconducting cavity overhead structure schematic diagram of a low-temperature thermostat based on low-temperature self-regulation is provided for the embodiment of the present application.

[0050] Figure 19 A support sliding mechanism structure schematic diagram of a low-temperature thermostat based on low-temperature self-regulation is provided for the embodiment of the present application.

[0051] Figure 20 A first connecting plate structure schematic diagram of a low-temperature thermostat based on low-temperature self-regulation is provided for the embodiment of the present application.

[0052] Figure 21 A valve structure schematic diagram of a low-temperature thermostat based on low-temperature self-regulation is provided for the embodiment of the present application. ​

[0053] Figure 22 A valve internal structure schematic diagram of a low-temperature thermostat based on low-temperature self-regulation is provided for the embodiment of the present application.

[0054] Figure 23 A low-temperature pipeline structure schematic diagram of a low-temperature thermostat based on low-temperature self-regulation is provided for the embodiment of the present application.

[0055] Figure 24 A vacuum chamber structure schematic diagram of a low-temperature thermostat based on low-temperature self-regulation is provided for the embodiment of the present application.

[0056] FIG. 1 is a thermostat bottom plate; 2 is a base support; 3 is a cold mass support; 31 is a low-temperature pipeline mounting support; 4 is a superconducting cavity; 401 is a first connecting plate; 402 is a second connecting plate; 403 is a waist hole; 404 is a bolt; 405 is a support sliding mechanism; 4051 is an upper sliding plate; 4052 is an upper fixed plate; 4053 is a lower sliding plate; 4054 is a lower fixed plate; 5 is a superconducting magnet; 501 is a third connecting plate; 502 is a fourth connecting plate; 6 is a beam center; 7 is a support assembly; 71 is a fixed support; 711 is a fixed support cylinder; 712 is a low-temperature end first inner flange; 713 is a low-temperature end first outer flange; 714 is a first heat sink inner flange; 715 is a first heat sink outer flange; 716 is a room temperature end first inner flange; 717 is a room temperature end first outer flange; 718 is a first cold screen support; 72 is a sliding support; 7201 is a sliding support cylinder; 7202 is a low-temperature end second inner flange; 7203 is a low-temperature end second outer flange; 7204 is a second heat sink inner flange; 7205 is a second heat sink outer flange; 7206 is a room temperature end second inner flange; 7207 is a room temperature end second outer flange; 7208 is an upper layer sliding rail; 7209 is a sliding block; 7210 is a second cold screen support; 7211 is a bottom layer sliding rail; 73 is a connecting piece; 731 is a first connecting table; 732 is a second connecting table; 733 is a guide column; 734 is a third connecting table; 735 is a fourth connecting table; 8 is a low-temperature pipeline; 81 is a main pipe; 82 is a branch pipe; 9 is a cold screen; 10 is a vacuum chamber; 101 is a connecting port; 1010 is a transmission rod; 1011 is a cross universal joint; 1012 is a sealing ring; 1013 is a limit stop ring; 11 is a valve; 1101 is a baffle; 12 is a negative pressure protection device. DETAILED DESCRIPTION

[0057] In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort belong to the scope of protection of the present application.

[0058] Referring to Figures 1 to 6 A low-temperature thermostat based on low-temperature self-regulation comprises a thermostat base plate 1, a base support 2, a cold mass support unit, a superconducting cavity 4, a superconducting magnet 5, a beam center 6, a support assembly 7, a low-temperature pipeline 8, a cold screen 9, a vacuum chamber 10, a valve 11, and a negative pressure protection device 12. The vacuum chamber 10 is fixedly connected to the top of the thermostat base plate 1, and a vacuum cavity is arranged in the vacuum chamber 10. The superconducting cavity 4, the superconducting magnet 5, the beam center 6, the support assembly 7, the low-temperature pipeline 8, the cold screen 9, and the valve 11 are all arranged in the vacuum cavity. The base support 2 is a height-adjustable bottom support structure and can be a commercially available part, and the specific structure is not described again. The cold mass support unit is adjustably arranged on the top of the thermostat base plate 1 through the support assembly 7. The cold mass support unit is provided with a mounting cavity of the superconducting cavity 4 and the superconducting magnet 5. The superconducting cavity 4 and the superconducting magnet 5 are adjustably mounted in the mounting cavity of the cold mass support unit. The superconducting cavity 4 is fixed at one end to the cold mass support unit and is in clearance fit at the other end to the other end of the cold mass support unit. The center line of the connecting pipeline connecting the superconducting cavities 4 and the superconducting magnets 5 in series forms the beam center 6.

[0059] The cold screen 9 is fixedly connected to the cold mass support unit. The connecting pipeline connecting the superconducting cavity 4 and the superconducting magnet 5 is provided with the valve 11 at both ends. The connecting pipeline is a beam vacuum. The ion beam runs in the beam vacuum. The opening and closing of the beam vacuum can be realized by opening the valve core of the valve 11. The low-temperature pipeline 8 is located above the cold screen 9. Figure 24 The negative pressure protection device 12 is fixedly connected to the top of the vacuum chamber 10. One end of the low-temperature pipeline 8 is connected to the negative pressure protection device 12, and the other end is connected to the superconducting cavity 4 and the superconducting magnet 5.

[0060] In this embodiment, the superconducting cavity 4 is fixed by sliding support mode, so that it can freely slide during the cooling process. According to the different cold shrinkage coefficients of different materials on the superconducting cavity 4, the installation and fixation points on both sides are pre-offset installed in X and Y directions. The cold mass support unit is pre-offset installed relative to the beam center 6 at room temperature, and returns to the beam line position of the beam center 6 at low temperature. At the same time, the cold shrinkage amount at low temperature is added to the height direction of the cold mass support unit. At room temperature, the height of the cold mass support unit is higher than the height under normal operation, so that the support assembly 7 can cold shrink according to the material properties of itself at low temperature, reach the normal operation height, and after low-temperature cold shrinkage, the thermostat can automatically realize the effect of collimation.

[0061] Referring to Figure 7 , Figure 8 , the support assembly 7 includes a fixed support 71 and a sliding support 72; the fixed support 71 includes a fixed support cylinder 711, a low-temperature end first inner flange 712, a low-temperature end first outer flange 713, a first heat sink inner flange 714, a first heat sink outer flange 715, a room-temperature end first inner flange 716, a room-temperature end first outer flange 717, and a first cold screen support 718;

[0062] Referring to Figure 9 , Figure 10 , Figure 11 , the top of the fixed support cylinder 711 is a low-temperature end, and the bottom is a room-temperature end. The outer wall of the top of the fixed support cylinder 711 is provided with the low-temperature end first outer flange 713 in interference fit, and the inner wall of the top is provided with the low-temperature end first inner flange 712 in interference fit. The low-temperature end first inner flange 712 is connected and fastened with the cold mass support unit through a hinge hole bolt. The outer wall of the middle of the fixed support cylinder 711 is fixedly connected with the first heat sink outer flange 715, and the inner wall is fixedly connected with the first heat sink inner flange 714. The outer wall of the first heat sink outer flange 715 is fixedly provided with the first cold screen support 718, which is used to support the cold screen 9 and obtain cold quantity from the cold screen 9, thereby playing the effect of heat sink and reducing the heat leakage of the low-temperature end cold mass support unit. The outer wall of the bottom of the fixed support cylinder 711 is fixedly connected with the room-temperature end first outer flange 717, and the inner wall of the bottom is fixedly connected with the room-temperature end first inner flange 716. The room-temperature end first inner flange 716 is fixedly connected with the thermostat bottom plate 1 and is positioned through an intermediate pin hole, thereby ensuring the installation precision. It should be noted that the low-temperature end first inner flange 712, the low-temperature end first outer flange 713, the first heat sink inner flange 714, the first heat sink outer flange 715, the room-temperature end first inner flange 716, and the room-temperature end first outer flange 717 are all in interference fit with the fixed support cylinder 711, and all maintain the relative position stable through the friction force of interference fit, with a bearing capacity greater than 50KN. The fixed support cylinder 711 is made of G10 / G11 material, has an extremely low thermal conductivity, and can obtain a high bearing capacity and a low heat leakage effect in a limited size.

[0063] Referring to Figure 12 , Figure 13 , Figure 14 , the sliding support 72 comprises a sliding support cylinder 7201, a low-temperature end second inner flange 7202, a low-temperature end second outer flange 7203, a second heat sink inner flange 7204, a second heat sink outer flange 7205, a room-temperature end second inner flange 7206, a room-temperature end second outer flange 7207, an upper-layer sliding rail 7208, a sliding block 7209, a second cold screen support 7210, and a bottom-layer sliding rail 7211; the length direction of the thermostat bottom plate 1 is defined as the X direction, the width direction is defined as the Y direction, and the height direction is defined as the Z direction;

[0064] Referring to Figure 8 , Figure 13 , the thermostat bottom plate 1 is fixedly connected with the bottom-layer sliding rail 7211 at the top, the bottom-layer sliding rail 7211 is arranged along the Y direction, the sliding block 7209 is slidably connected to the bottom-layer sliding rail 7211, the upper-layer sliding rail 7208 is slidably connected to the top of the sliding block 7209, the upper-layer sliding rail 7208 is arranged along the X direction, the upper-layer sliding rail 7208 is fixedly connected with the sliding support cylinder 7201 through the room-temperature end second inner flange 7206, the top of the sliding support cylinder 7201 is the low-temperature end, and the bottom is the room-temperature end, the low-temperature end second outer flange 7203 is in interference fit with the outer wall of the top of the sliding support cylinder 7201, and the low-temperature end second inner flange 7202 is in interference fit with the inner wall of the top of the sliding support cylinder 7201, the low-temperature end second inner flange 7202 is connected and fastened with the bottom of the cold mass support unit through the hinge hole bolt, the second heat sink outer flange 7205 is fixedly connected with the outer wall of the middle of the sliding support cylinder 7201, and the second heat sink inner flange 7204 is fixedly connected with the inner wall of the middle of the sliding support cylinder 7201, the second cold screen support 7210 is fixedly arranged on the outer wall of the second heat sink outer flange 7205, the second cold screen support 7210 is used for supporting the cold screen 9 and obtaining cold energy from the cold screen 9, thereby playing a heat sink effect and reducing the heat leakage of the low-temperature end cold mass support unit, the room-temperature end second outer flange 7207 is fixedly connected with the outer wall of the bottom of the sliding support cylinder 7201, and the room-temperature end second inner flange 7206 is fixedly connected with the inner wall of the bottom of the sliding support cylinder 7201, the sliding support cylinder 7201 is made of G10 / G11 material, has an extremely low thermal conductivity, and can obtain a high bearing capacity and a low heat leakage effect in a limited size.

[0065] Referring to Figure 15 , Figure 16 , Figure 17The cold mass support unit comprises two cold mass support parts, each of which comprises two symmetrically arranged cold mass supports 3, namely a left cold mass support 3 and a right cold mass support 3. The four cold mass supports 3 are counted as a first, a second, a third and a fourth cold mass support 3 from left to right, respectively. The first cold mass support part and the second cold mass support part are fixedly connected with two fixed supports 71 and four sliding supports 72 at the bottom. The cold mass support 3 has a rectangular structure with a Y-direction length greater than an X-direction length. The two fixed supports 71 are fixedly arranged at the middle of the two cold mass supports 3. One of the fixed supports 71 is fixedly connected to the left side of the first cold mass support 3, and the other fixed support 71 is fixedly connected to the right side of the second cold mass support 3. The two sliding supports 72 are fixedly connected to the right side of the first cold mass support 3 and symmetrically arranged along the Y-direction centerline of the first cold mass support 3. The second cold mass support part has the same structure as the first cold mass support part. The second cold mass support part comprises a third cold mass support 3 and a fourth cold mass support 3 arranged in sequence along the direction of the beam center 6. The third cold mass support 3 and the fourth cold mass support 3 are fixedly connected with a fixed support 71 at the center of the left side of the third cold mass support 3 and the right side of the fourth cold mass support 3, respectively. The third cold mass support 3 and the fourth cold mass support 3 are fixedly connected with two sliding supports 72 at the center of the right side of the third cold mass support 3 and the left side of the fourth cold mass support 3, respectively, and symmetrically arranged along the Y-direction centerline of the third cold mass support 3. The four fixed supports 71 are located on the same straight line. The four cold mass supports 3 can be limited by the four fixed supports 71. At low temperature, the sliding supports 72 are cold contracted and have X-direction and Y-direction offsets. When the X-direction offset occurs, the sliding support barrel 7201 drives the upper slide rail 7208 to slide along the X-direction of the sliding block 7209. When the Y-direction offset occurs, the sliding support barrel 7201 drives the sliding block 7209 to slide along the bottom slide rail 7211 (i.e., the Y-direction) through the upper slide rail 7208. Therefore, during installation, the cold mass support 3 is pre-offset installed according to the offset amount at low temperature. On the mass-produced thermostat, the pre-offset amount in three directions is based on theoretical calculation, and a collimation measurement can be performed at low temperature to check and correct the pre-offset amount, thereby further improving the collimation at low temperature.

[0066] Referring to Figure 17 The cold mass support unit further comprises a low-temperature pipeline mounting bracket 31 fixedly connected to the top of the cold mass support 3 for supporting the low-temperature pipeline 8.

[0067] Referring to Figure 18The first connecting plate 401 is fixedly connected to one end of the superconducting cavity 4, and the second connecting plate 402 is fixedly connected to the other end of the superconducting cavity 4. The cold mass support 3 is fixedly connected to the connecting pieces 73 which are adapted to the first connecting plate 401 and the second connecting plate 402 at two ends, respectively. The connecting piece 73 comprises a first connecting table 731, a second connecting table 732 and a guide column 733. The first connecting table 731 is located on the same side of the superconducting cavity 4 as the first connecting plate 401. The second connecting table 732 is located on the same side of the superconducting cavity 4 as the second connecting plate 402. The second connecting plate 402 is a rectangular plate. Two waist holes 403 are formed in the top of one end of the second connecting plate 402. The guide column 733 is fixed to the corresponding position of the second connecting table 732 and the waist hole 403. The waist hole 403 is adapted to the shape of the guide column 733 and limits the guide column 733. The second connecting plate 402 is fastened to the second connecting table 732 through the bolt 404 at the middle of the top of one end of the second connecting plate 402. At low temperature, the two ends of the second connecting plate 402 are cold contracted to the middle because the middle of the second connecting table 732 is fixed. The second connecting plate 402 is a U-shaped plate. The large end surface of the second connecting plate 402 is fixedly connected to the superconducting cavity 4. The two small end surfaces of the second connecting plate 402 are slidably fixed to the first connecting table 731 through the support sliding mechanism 405. Referring to Figure 19 、 Figure 20 The support sliding mechanism 405 comprises an upper sliding plate 4051, an upper fixed plate 4052, a lower sliding plate 4053 and a lower fixed plate 4054. The two small end surfaces of the second connecting plate 402 are provided with mounting holes. The mounting holes are through holes with steps. The step size is adapted to the size of the upper sliding plate 4051, the upper fixed plate 4052, the lower sliding plate 4053 and the lower fixed plate 4054. The lower fixed plate 4054 is located at the bottom of the lower sliding plate 4053 and is slidably connected to the lower sliding plate 4053 through a plurality of ball bodies with the same diameter. The top of the lower fixed plate 4054 is arranged with recesses adapted to the ball bodies at equal angles along the circumferential direction. The recesses limit the ball bodies and prevent the ball bodies from sliding out of the recesses. It should be noted that the radius of the ball body is greater than the total cold contraction amount of the superconducting cavity 4, the first connecting plate 401 and the second connecting plate 402. The lower sliding plate 4053 is clamped in the mounting hole. The lower fixed plate 4054 is fixedly connected to the second connecting table 732, thereby achieving the sliding support of the first connecting table 731 and the superconducting cavity 4. The upper fixed plate 4052 is fixedly connected in the mounting hole. The upper sliding plate 4051 is slidably connected to the upper fixed plate 4052 through a plurality of ball bodies.

[0068] Referring to Figure 2 、 Figure 18, the first cold mass support 3 is provided with two superconducting cavities 4, the second cold mass support 3 is provided with one superconducting cavity 4 and one superconducting magnet 5, the third cold mass support 3 is provided with two superconducting cavities 4, the fourth cold mass support 3 is provided with one superconducting cavity 4 and one superconducting magnet 5, the adjacent superconducting cavities 4 are sequentially communicated through the telescopic bellows, the superconducting magnet 5 is communicated with the adjacent superconducting cavities 4 through the telescopic bellows at both ends, the right end of the superconducting magnet 5 on the fourth cold mass support 3 is connected with the beam center 6 through the telescopic bellows, refer to Figure 21 、 Figure 22 , the valve 11 is arranged on the beam center 6, the cold mass needs to be assembled in the clean room, and after the assembly is completed, it is transferred to the outside for the overall assembly of the thermostat, before leaving the clean room, the beam vacuum needs to be closed and protected, therefore, one valve 11 is arranged at both ends of the first cold mass support 3 and the fourth cold mass support 3, after the installation of the thermostat is completed, the valve 11 is fixedly connected in the inner side of the vacuum chamber 10, the vacuum chamber 10 is fixedly connected with a connecting port 101, the connecting port 101 is rotatably connected with a transmission rod 1010, and the rotation sealing is realized through a sealing ring 1012, the valve 11 is movably connected with a baffle 1101, the baffle 1101 (valve core) is coaxial with the axis of the beam center 6, the valve 11 is a commercially available part, the right side of the valve 11 has an input end, rotating the input end can drive the baffle 1101 to slide in the valve 11, so as to realize the closing or opening of the beam vacuum, one end of the transmission rod 1010 is formed with a hexagonal screw port, the other end is drivingly connected with the input end of the valve 11 through a cross universal joint 1011, the cross universal joint 1011 can realize eccentric transmission, the transmission rod 1010 is fixedly connected with a limiting baffle ring 1013, so as to prevent the transmission rod 1010 from being sucked into the vacuum.

[0069] refer to Figure 18 , the superconducting magnet 5 is movably fixed on the second cold mass support 3, one end of the superconducting magnet 5 is fixedly connected with a third connecting plate 501, the other end is fixedly connected with a fourth connecting plate 502, the second cold mass support 3 is fixedly connected with a third connecting table 734 and a fourth connecting table 735, the third connecting table 734 is located on the same side as the third connecting plate 501, the fourth connecting table 735 is located on the same side as the fourth connecting plate 502, the fourth connecting table 735 is fixedly connected with the fourth connecting plate 502 through two bolts, and the third connecting plate 501 is slidingly fixed with the third connecting table 734 through the supporting sliding mechanism 405.

[0070] refer to Figure 23The low-temperature pipeline 8 provides refrigerant for cold mass, and comprises a main pipe 81 and branch pipes 82. The main pipe 81 comprises a horizontal section and a vertical section, and the vertical section of the main pipe 81 is provided with an expansion bellows to take into account the cold shrinkage in the height direction. The horizontal section of the main pipe 81 is connected with a plurality of branch pipes 82 at the bottom. The superconducting cavity 4 and the superconducting magnet 5 are both provided with a connecting pipe at the top. The branch pipes 82 are respectively connected with the connecting pipes through an expansion bellows. The expansion bellows can compensate for the low-temperature cold shrinkage. The expansion bellows are horizontally installed, which is conducive to compensating for the large cold shrinkage displacement in the beam direction. The fixing points of the low-temperature pipeline 8 are arranged at the middle positions, and the main pipe 81 is symmetrically arranged on both sides. Whether the operation is under negative pressure or positive pressure, the forces of the expansion bellows will be counteracted, and no impact will be caused to the main pipe 81, so as to maintain the stability of the pipeline.

[0071] The above examples are only used to illustrate the technical solutions of the present application, but not to limit it. Although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that the technical solutions recorded in the foregoing examples can be modified, or some technical features can be replaced by equivalent ones. The modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A low-temperature self-regulating cryostat, characterized in that, The system includes a thermostat base plate, a cold mass support unit, and a support assembly. The cold mass support unit is slidably fixed to the top of the thermostat base plate via the support assembly. At room temperature, the cold mass support unit is pre-offset relative to the thermostat base plate. The pre-offset amount of the cold mass support unit is the amount of material contraction at low temperatures. The cold mass support unit includes a cold mass support section, on which multiple superconducting cavities and superconducting magnets are mounted in series. The cold mass support section includes two symmetrically distributed cold mass supports. One end of each superconducting cavity is fixedly connected to a cold mass support, and the other end is movably connected to a cold mass support. One end of the superconducting magnet is fixedly connected to the cold mass support, and the other end is movably connected to the cold mass support. Adjacent superconducting cavities are connected by telescopic bellows. Both ends of the superconducting magnet are connected to the superconducting cavity through telescopic bellows. A first connecting plate and a second connecting plate are fixedly connected to both ends of the superconducting cavity, respectively. The ends of the cold mass support connected to the superconducting cavity are fixed with connecting parts adapted to the first connecting plate and the second connecting plate, respectively. The connecting parts include a first connecting platform and a second connecting platform. The first connecting plate and the first connecting platform are slidably connected by a support sliding mechanism. The second connecting plate is connected and fastened to the second connecting platform by bolts.

2. A low-temperature self-regulating cryostat according to claim 1, characterized in that, The centerline of the connecting pipes that connect multiple superconducting cavities and superconducting magnets in series forms the beam center.

3. A low-temperature self-regulating cryostat according to claim 2, characterized in that, The support assembly includes fixed supports and sliding supports. The middle of each side of the cold mass support is fixedly connected to the thermostat base plate through a fixed support. The free end of the cold mass bracket is slidably fixed to the thermostat base plate through two sliding supports. The line connecting the two fixed supports coincides with the vertical projection of the beam center axis. The free end of the cold mass bracket slides toward the fixed support of the cold mass support at low temperature.

4. A low-temperature self-regulating cryostat according to claim 3, characterized in that, The two cold mass supports are a left cold mass support and a right cold mass support. The bottom left end of the left cold mass support and the bottom right end of the right cold mass support are fixed to the thermostat base plate by fixed supports. The bottom right end of the left cold mass support and the bottom left end of the right cold mass support are slidably fixed to the thermostat base plate by two sliding supports.

5. A low-temperature self-regulating cryostat according to claim 1, characterized in that, The second connecting plate is a rectangular plate with waist holes on both sides of the top end facing the second connecting platform. A guide post is fixed on the top of the second connecting platform. The waist holes are adapted to the guide post. The bolt is located at the center of the line connecting the two waist holes.

6. A low-temperature self-regulating cryostat according to claim 5, characterized in that, The supporting sliding mechanism includes a lower sliding plate and a lower fixed plate. The first connecting plate is a U-shaped plate with its large end face fixedly connected to the superconducting cavity. Both small end faces of the first connecting plate are formed with mounting holes adapted to the lower sliding plate. The lower sliding plate is fixedly connected in the mounting holes. The lower fixed plate is fixedly embedded in the top of the cold mass support. The lower sliding plate slides in cooperation with the lower fixed plate through multiple spheres.

7. A low-temperature self-regulating cryostat according to claim 1, characterized in that, The superconducting magnet has a third connecting plate and a fourth connecting plate fixedly connected to its two ends, respectively. The top of the cold mass support has a third connecting platform and a fourth connecting platform that are adapted to the third connecting plate and the fourth connecting plate. The fourth connecting plate is fixedly connected to the fourth connecting platform, and the third connecting plate is slidably connected to the third connecting platform through a support sliding mechanism.

8. A low-temperature self-regulating cryostat according to claim 4, characterized in that, The sliding support includes a sliding support cylinder, a second inner flange at the low temperature end, a second outer flange at the second heat sink end, a second inner flange at the room temperature end, an upper slide rail, a slider, a second cold shield support, and a bottom slide rail. Multiple bottom slide rails are fixedly connected to the top of the thermostat base plate. A slider is slidably connected to the bottom slide rail. An upper slide rail is slidably connected to the top of the slider. The vertical projections of the bottom slide rail and the upper slide rail form a cross-shaped structure. The top of the upper slide rail is fixedly connected to the sliding support cylinder through the second inner flange at the room temperature end. The inner wall of the top of the sliding support cylinder is interference-fitted with the second inner flange at the low temperature end, and is fixedly connected to the cold mass support through the second inner flange at the low temperature end.

9. A low-temperature self-regulating cryostat according to claim 8, characterized in that, The cold mass support is provided with a cold screen on the outside, and a second heat sink outer flange is fixedly connected to the outer wall of the sliding support cylinder. The second heat sink outer flange is supported and fixed to the cold screen by the second cold screen.

10. A low-temperature self-regulating cryostat according to claim 8, characterized in that, The sliding support also includes a second outer flange at the low temperature end, a second inner flange at the second heat sink, and a second outer flange at the room temperature end. The second outer flange at the low temperature end is fixedly installed on the top outer wall of the sliding support cylinder, and the second inner flange at the second heat sink is fixedly installed on the inner wall of the sliding support cylinder. The plane where the second inner flange is located is on the same plane as the plane where the second outer flange at the second heat sink is located. The second outer flange at the room temperature end is fixedly connected to the bottom outer wall of the sliding support cylinder.

11. A low-temperature self-regulating cryostat according to claim 9, characterized in that, A vacuum chamber is fixed to the top of the thermostat base plate. A vacuum cavity is opened in the vacuum chamber. The cold screen is located in the vacuum cavity. A vacuum pipeline is also provided in the cold screen. The cold mass support unit also includes a low-temperature pipeline mounting bracket. The low-temperature pipeline mounting bracket is fixed to the top of the cold mass support and provides installation support for the low-temperature pipeline.

12. A low-temperature self-regulating cryostat according to claim 11, characterized in that, The cryogenic pipeline includes a main pipe and branch pipes. The main pipe includes a vertical section and a horizontal section. A telescopic corrugated pipe is provided on the vertical section of the main pipe. Multiple branch pipes are connected to the bottom of the horizontal section of the main pipe. A connecting pipe is provided at the top of the superconducting cavity and the superconducting magnet. The branch pipes are respectively connected to the connecting pipes through telescopic corrugated pipes.

13. A low-temperature self-regulating cryostat according to claim 11, characterized in that, Both ends of the connecting pipe are equipped with valves. The connecting pipe contains a beam vacuum. The vacuum chamber is equipped with a connection port. The connection port is rotatably connected to a transmission rod. The transmission rod is connected to the telescopic end of the valve through a universal joint. By rotating the transmission rod, the valve core inside the valve can be moved to achieve the sealing or opening of the beam vacuum.

14. A low-temperature self-regulating cryostat according to claim 12, characterized in that, The telescopic corrugated pipe connecting the branch pipe and the connecting pipe is installed horizontally.

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