Magnet repair process of liquid-helium-free nuclear magnetic resonance spectrometer

Abstract

The invention relates to a magnet repair process of a liquid-helium-free nuclear magnetic resonance spectrometer, and belongs to the technical field of liquid-helium-free nuclear magnetic resonance instruments. The method comprises the following steps: 1) dismounting a magnet cold head and a service tower plate assembly; (2) the room-temperature lower end plate is dismantled; 3) dismounting the lower end plate of the cold shield; 4) mounting a magnet assembly base on the end face of the magnet lower end plate; (5) hoisting blocks are installed at the two ends of the room temperature cylinder assembly, and the magnet device is integrally hoisted and overturned by 90 degrees through auxiliary repairing equipment; (6) the magnet device is vertically placed through a magnet assembling base, and the room temperature cylinder assembly, the cold screen and the supporting inner and outer cylinder assembly are sequentially dismantled in the vertical state; (7) the cold body assembly makes contact with the outside world, and a maintainer inspects the performance of a diode of the cold body assembly, replaces a high-temperature superconducting current lead component, replaces a superconducting switch, remanufactures a superconducting connector, conducts local heat conduction strengthening treatment on a magnet and other maintenance operations. The method has the effect of improving the maintenance efficiency of the cold body assembly.

Description

Technical Field

[0001] The present application relates to the technical field of liquid helium-free nuclear magnetic resonance instruments, and in particular to a magnet repair process for liquid helium-free nuclear magnetic resonance instruments. Background Art

[0002] Magnetic resonance imaging is an advanced medical imaging device with broad application prospects and important clinical value.

[0003] Existing nuclear magnetic resonance (NMR) instruments consist of a horizontally positioned cylinder, consisting, from the inside out, of a cooling assembly, a cold shield, supporting inner and outer cylinder assemblies, and a room-temperature cylinder assembly. The sidewalls of the room-temperature cylinder assembly are equipped with a magnet base for support. Superconducting magnets can experience various faults during operation, such as abnormal temperatures, magnetic fields, and currents. If not addressed promptly, these faults can severely degrade magnet performance or even damage the magnet. Maintenance procedures can monitor the magnet's operating status in real time, allowing these faults to be detected and addressed promptly, preventing them from developing and causing further damage.

[0004] The maintenance is mainly aimed at the inner cold body assembly, so the room temperature cylinder assembly, cold screen and supporting inner and outer cylinder assemblies need to be removed during maintenance. However, the cold body assembly is in a suspended state after removal, and additional equipment is required to fix the cold body assembly, which makes maintenance more difficult and cumbersome. Summary of the Invention

[0005] In order to improve the maintenance efficiency of the cold body assembly, the present application provides a magnet repair process for a liquid helium-free nuclear magnetic resonance instrument.

[0006] The present application provides a magnet repair process for a liquid helium-free nuclear magnetic resonance instrument using the following technical solutions: A magnet repair process for a liquid helium-free nuclear magnetic resonance instrument comprises the following steps: 1) Remove the magnet cold head and service tray assembly; 2) Remove the end plate at room temperature; 3) Remove the lower end plate of the cold screen; 4) Install the magnet assembly base on the end surface of the lower end plate of the magnet; 5) Use the auxiliary rework equipment, fix one end to the room temperature cylinder assembly and the other end to the magnet base, and flip the NMR instrument 90°; 6) Place the NMR instrument vertically on the magnet assembly base. Remove the room temperature cylinder assembly, cold shield, and supporting inner and outer cylinder assemblies in sequence while in the vertical position. 7) After the room temperature cylinder assembly, cold screen and supporting inner and outer cylinder assemblies are removed, the cold body assembly is exposed to the outside world. The maintenance personnel check the performance of the diodes on the cold body assembly, replace the high-temperature superconducting current lead components, replace the superconducting switch, remake the superconducting joints, and perform local heat conduction enhancement treatment on the magnet.

[0007] By adopting the above technical solution and auxiliary repair equipment, the nuclear magnetic resonance instrument as a whole can be rotated from a horizontal state to a vertical state, and then the room temperature cylinder assembly, the cold screen and the supporting inner and outer cylinder assemblies can be removed, so that the cold body assembly is in direct contact with the outside world, which is convenient for maintenance personnel to perform maintenance; at the same time, before rotation, the magnet assembly base is first installed on the lower end plate of the magnet, so that the vertical state of the cold body assembly is supported by the magnet assembly base, ensuring stability during maintenance. Optionally, the auxiliary rework equipment includes a traveling crane mechanism, a placement mechanism for installing a nuclear magnetic resonance apparatus, and a dismantling mechanism installed on the traveling crane mechanism; the traveling crane mechanism includes a traveling crane support frame, a lifting component slidably installed on the traveling crane support frame, and a walking component that drives the lifting component to slide along the length direction of the traveling crane support frame.

[0008] By adopting the above technical solution, the structural composition of the auxiliary rework equipment is disclosed. The traveling crane mechanism hoisted and moved the nuclear magnetic resonance instrument to the placement mechanism, and then the room temperature cylinder assembly was removed by the traveling crane mechanism. The cold screen and supporting inner and outer cylinder assemblies were removed by the removal mechanism. The setting of the placement mechanism can ensure the hoisting and dismantling stability of the nuclear magnetic resonance instrument and improve the stability.

[0009] Optionally, the lifting assembly includes a lifting frame and a first winding mechanism and a second winding mechanism provided on the lifting frame, the first winding mechanism is provided with a first lifting hook, and the second winding mechanism is provided with a second lifting hook; one side end of the room temperature cylinder assembly is provided with a first lifting block that cooperates and is fixed with the first lifting hook, and the other side end of the room temperature cylinder is provided with a second lifting block that cooperates and is fixed with the second lifting hook.

[0010] By adopting the above technical solution, the first lifting hook and the second lifting hook of the two sets of winding mechanisms are used to hoist the two ends of the room temperature cylinder assembly respectively. By adjusting the lifting speed of the two lifting hooks, the room temperature cylinder assembly can be rotated, so that the nuclear magnetic resonance apparatus is switched from a horizontal state to a vertical state.

[0011] Optionally, the first lifting block is located on one side of the room temperature lower end plate, and the second lifting block is located on one side of the room temperature upper end plate; the second lifting block is rotatably mounted on the room temperature upper end plate, an arc-shaped rotation groove is provided on the end surface of the room temperature upper end plate, and locking members for locking the second lifting block are provided at both ends of the arc-shaped rotation groove of the room temperature upper end plate; The locking member includes an L-shaped plate fixed to the room temperature cylinder assembly and a positioning bolt group installed on the L-shaped plate. The end surface of the second lifting block is provided with a lifting hole for lifting and a locking hole for cooperating with the positioning bolt group.

[0012] By adopting the above technical solution, the second lifting block is rotatably installed on the upper end plate at room temperature, so that the second lifting block has two states at both ends of the arc-shaped rotating groove. When the second lifting block and the first lifting block are at the same height, it is convenient for the lifting mechanism to lift the nuclear magnetic resonance instrument smoothly. When the second lifting block and the first lifting block are at different heights, it is convenient for the two sets of winding mechanisms to rotate the nuclear magnetic resonance instrument.

[0013] Optionally, the second lifting block is provided with a sliding portion cooperating with the arc-shaped rotating groove, the side wall of the sliding portion is provided with a pulley member abutting against the inner wall of the arc-shaped rotating groove, the end side walls of the arc-shaped rotating groove are provided with a plunger member, and the sliding portion is provided with a locking hole cooperating with the plunger member; The plunger member includes a plunger housing, a plunger spring and a plunger locking block. The side wall of the plunger locking block is provided with a driving inclined surface for the rotating part to abut.

[0014] By adopting the above technical solution, the setting of the pulley part on the sliding part improves the sliding efficiency of the second lifting block in the arc-shaped rotating groove. The setting of the locking hole and the plunger part enables the sliding part to achieve preliminary positioning after moving to one end of the arc-shaped rotating groove, which is convenient for the final fixation of the bolt.

[0015] Optionally, an unlocking block is slidably installed on the sliding portion, and the sliding direction of the unlocking block is parallel to the moving direction of the plunger locking block. The unlocking block is the inner wall of the locking hole toward the top of the arc-shaped rotating groove. When the unlocking block slides, the side wall of the locking hole toward the top of the arc-shaped rotating groove gradually changes from a closed shape to an open shape.

[0016] By adopting the above technical solution, when it is necessary to release the lock of the plunger and the locking hole, the unlocking blocks on both sides are moved so that the unlocking blocks move toward each other, so that one side of the locking hole is open, and the second lifting block is moved from one end of the arc-shaped rotating groove to the other end.

[0017] Optionally, the placement mechanism includes a placement frame and an auxiliary frame rotatably mounted on the placement frame and for placing the room-temperature cylinder. The auxiliary frame has an arc-shaped placement groove that cooperates with the side wall of the room-temperature cylinder, and a mounting through hole is opened on the bottom wall of the arc-shaped placement groove. The room-temperature cylinder assembly has an outer cylinder support passing through the mounting through hole. When the rotating drive rotates the auxiliary frame to a vertical state, there is a gap between the bottom of the magnet assembly base and the bottom of the placement mechanism.

[0018] By adopting the above technical solution, the structural composition of the placement mechanism is disclosed. Before rotating the nuclear magnetic resonance instrument, two sets of winding mechanisms horizontally hoist the nuclear magnetic resonance instrument on the auxiliary frame so that the outer cylinder support is inserted into the mounting through hole. Then, the position of the second hoisting block is adjusted so that the two hoisting blocks are located at different heights. The winding mechanism is started to rotate the nuclear magnetic resonance instrument and the auxiliary frame 90 degrees. Finally, the auxiliary frame and the room temperature cylinder assembly are synchronously hoisted through the winding mechanism.

[0019] Optionally, rotating parts are provided on opposite sides of the auxiliary frame, the placement frame includes a fixed frame and a lifting frame installed on the fixed frame, the lifting frame has a rotating groove for installing the rotating part, and the top of the rotating groove is open; Arc-shaped driving parts are provided on both sides of the rotating part, and a first sliding post for abutting the arc-shaped driving part is slidably installed in the lifting frame body, and two second sliding posts are slidably provided on the end of the first sliding post away from the arc-shaped driving part of the lifting frame body, and a locking protrusion is provided on the top of the placement frame body, and the locking protrusion has a sliding cavity for installing the second sliding post, and the locking protrusion and the lifting frame body are plugged into each other; When the rotating part rotates 90 degrees, the rotating part drives the first sliding post to slide, and the first sliding post drives the second sliding post to slide, so that the second sliding post is separated from the sliding chamber, and the lifting frame and the placement frame are unlocked.

[0020] By adopting the above technical solution, the auxiliary frame is rotatably installed in the rotating slot of the lifting frame body through the rotating part, and the top of the rotating slot is open, so that after the auxiliary frame is rotated 90 degrees, the lifting of the winding mechanism can separate the auxiliary frame from the lifting frame body. The cooperation of the arc-shaped driving part, the first slide column and the second slide column enables the lifting frame body and the placement frame to be unlocked after the auxiliary frame is rotated, so that the magnet assembly base can move downward under the action of the lifting frame body, so that the support wheel abuts against the bottom surface, thereby achieving stable support of the cold body component.

[0021] Optionally, the dismantling mechanism is a third winding mechanism provided on the overhead crane mechanism, and the lifting hook of the third winding mechanism is provided with a locking clamp for locking the cold screen and supporting the inner and outer cylinder assemblies.

[0022] By adopting the above technical solution, the dismantling mechanism is a winding mechanism, which can lift and remove the locking cold screen and the supporting inner and outer cylinder components from the nuclear magnetic resonance instrument, so that the cold body components are exposed to the outside world. The lifting and dismantling method using the winding mechanism has a simple structure and high dismantling efficiency.

[0023] Optionally, the magnet assembly base includes a magnet support base fixed to the lower end plate of the magnet and multiple sets of magnet support wheels arranged on the magnet support base, the magnet support base is provided with a support connecting plate for fitting the lower end plate of the magnet, the lower end plate of the magnet is provided with a support positioning groove for positioning the support connecting plate, and the support positioning groove is provided with a support bolt hole for fixing to the support connecting plate.

[0024] By adopting the above technical solution, the structural composition of the magnet assembly base is disclosed. Before installing the magnet assembly base, the room temperature lower end plate and the cold screen lower end plate are removed in advance, so that the magnet assembly base is directly fixed to one end of the cold body assembly. After the nuclear magnetic resonance apparatus is switched to a vertical state, the cold body assembly is supported by the magnet assembly base, which facilitates the movement of the cold body assembly and does not require additional equipment for clamping the cold body assembly.

[0025] In summary, this application includes at least one of the following beneficial technical effects: 1. The magnet repair process of this application improves the maintenance efficiency of the internal cold body components of liquid helium-free nuclear magnetic resonance instruments; 2. The present application sets up a magnetic assembly base, so that after disassembling the room temperature cylinder assembly, the cold screen and the supporting inner and outer cylinder assemblies, the cold body assembly can be arranged vertically through the magnetic assembly base, which is convenient for maintenance personnel to perform maintenance operations; 3. The present application can assist the rotation of the MRI apparatus by setting up a placement mechanism, thereby improving the stability of the MRI apparatus during rotation, so that after the MRI apparatus is rotated to 90 degrees, the lifting frame and the fixed frame are unlocked, and the MRI apparatus slowly descends, so that the magnet assembly base contacts the ground. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematic diagram of the explosion of the liquid helium-free nuclear magnetic resonance instrument according to an embodiment of the present application.

[0027] Figure 2 2 is a cross-sectional schematic diagram of a liquid helium-free nuclear magnetic resonance instrument according to an embodiment of the present application.

[0028] Figure 3 yes Figure 2 A local enlarged schematic diagram of point A in the middle.

[0029] Figure 4 It is a structural schematic diagram of the magnet assembly base and the magnet lower end plate of an embodiment of the present application.

[0030] Figure 5 It is a structural diagram of the auxiliary rework equipment according to an embodiment of the present application.

[0031] Figure 6 This is a structural diagram of the room temperature cylinder assembly after the lifting block is installed in the embodiment of the present application.

[0032] Figure 7 It is a cross-sectional schematic diagram of the cooperation between the sliding portion and the arc-shaped rotating groove in an embodiment of the present application.

[0033] Figure 8 yes Figure 6 A partial enlarged schematic diagram of point B in the middle.

[0034] Figure 9 It is a structural diagram of the placement mechanism of an embodiment of the present application.

[0035] Figure 10 It is a schematic cross-sectional view in the vertical direction when the lifting frame and the fixed frame are locked according to the embodiment of the present application.

[0036] Figure 11 This is a horizontal cross-sectional diagram of the embodiment of the present application when the lifting frame and the fixed frame are locked. Explanation of reference numerals: 1. Cryogen-free nuclear magnetic resonance instrument; 11. Cold body assembly; 111. Lower end plate of magnet; 1111. Support positioning groove; 12. Cold shield and supporting inner and outer cylinder assembly; 121. Cold shield assembly; 122. Support outer cylinder; 123. Support inner cylinder; 124. Lower end plate of cold shield; 125. Upper end plate of cold shield; 126. Lower flange of supporting outer cylinder; 13. Room temperature cylinder assembly; 131. Room temperature outer cylinder; 132. Room temperature outer cylinder flange; 133. Room temperature lower end plate; 134. Room temperature upper end plate; 1 341, arc-shaped rotating groove; 1342, plunger; 13421, guide slope; 135, outer cylinder support; 136, first lifting block; 137, second lifting block; 1371, lifting hole; 1372, fixing hole; 1373, sliding part; 13731, locking hole; 1374, unlocking block; 1375, fixing plate; 1376, driving rod; 1377, limit block; 14, magnet cold head; 15, service tower plate assembly; 16, locking piece; 2, magnet assembly base; 21, magnet 2. Support chassis; 22. Magnetic support wheel; 221. Rectangular frame; 222. Support connector; 2221. Support connector rod; 2222. Support connector plate; 3. Traveling crane mechanism; 31. Traveling crane support frame; 311. Vertical frame; 312. Horizontal frame; 32. Lifting assembly; 321. Lifting frame; 322. First winding mechanism; 3221. First lifting hook; 323. Second winding mechanism; 3231. Second lifting hook; 33. Traveling assembly; 331. First traveling member; 33 2. Second walking member; 4. Placement mechanism; 41. Placement frame; 411. Fixed frame; 4111. Locking protrusion; 4112. Sliding chamber; 4113. Drive socket; 412. Lifting frame; 4121. Rotation slot; 4122. First slide post; 41221. Drive slope; 4123. Second slide post; 42. Auxiliary frame; 421. Arc-shaped placement slot; 422. Positioning through hole; 423. Rotation part; 424. Arc-shaped drive part; 5. Removal mechanism; 51. Locking clamp. DETAILED DESCRIPTION

[0037] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Since the embodiments disclosed in the present invention can be set in different directions, these terms indicating directions are only for illustration and should not be regarded as limitations. For example, "up" and "down" are not necessarily limited to directions opposite to or consistent with the direction of gravity. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of such features.

[0038] The following is combined with Figure 1-11 This application is described in further detail.

[0039] The embodiments of the present application disclose a magnet repair process for a liquid helium-free nuclear magnetic resonance apparatus.

[0040] Reference Figure 1 The liquid helium-free nuclear magnetic resonance apparatus 1 includes, from the inside to the outside, a cold body assembly 11, a cold shield and supporting inner and outer cylinder assemblies 12, and a room temperature cylinder assembly 13.

[0041] Combine Figure 2 and Figure 3 The room temperature cylinder assembly 13 includes a room temperature outer cylinder 131, a room temperature outer cylinder flange 132, a room temperature lower end plate 133, a room temperature upper end plate 134 and an outer cylinder support 135. The two ends of the room temperature outer cylinder 131 are fixed to the room temperature outer cylinder flange 132 and the room temperature upper end plate 134 respectively. The room temperature lower end plate 133 is fixed to the room temperature outer cylinder flange 132 by bolts. Two sets of outer cylinder supports 135 are fixedly installed on the side wall of the room temperature outer cylinder 131, and the liquid helium-free nuclear magnetic resonance apparatus 1 is placed horizontally on the ground through the outer cylinder supports 135. Among them, the magnet cold head 14 and the magnet service tower plate assembly 15 are installed on the top of the side wall of the room temperature outer cylinder 131. The magnet cold head 14 and the magnet service tower plate are connected to the cold body assembly 11 through the room temperature cylinder assembly 13, the cold screen and the supporting inner and outer cylinder assembly 12.

[0042] The cold shield and support inner and outer cylinder assembly 12 includes a cold shield assembly 121, a support outer cylinder 122, and a support inner cylinder 123. A cold shield lower end plate 124 and a cold shield upper end plate 125 are mounted on both ends of the cold shield assembly 121. One end of the support outer cylinder 122 is secured to the room temperature lower end plate 133 via a support outer cylinder lower flange 126.

[0043] During maintenance, the magnet cold head 14 and the magnet service tower plate assembly 15 are removed from the room temperature outer cylinder 131, and then the room temperature lower end plate 133 and the cold screen lower end plate 124 are removed, so that the magnet lower end plate 111 of the cold body assembly 11 is in contact with the outside world, and then the magnet assembly base 2 is installed on the end face of the magnet lower end plate 111.

[0044] Reference Figure 4 The magnet assembly base 2 includes a magnet support base 21 and a magnet support wheel 22. The magnet support wheel 22 includes a rectangular frame 221 and support connectors 222 fixed to the four corners of the rectangular frame 221. The support connectors 222 include a support connecting rod 2221 and support connecting plates 2222 fixed to both ends of the support connecting rod 2221. The support connecting plate 2222 on one side is fixed to the magnet lower end plate 111 by bolts, and the support connecting plate 2222 on the other side is fixedly connected to the magnet support wheel 22. Among them, the end surface of the magnet lower end plate 111 has a support positioning groove 1111 for positioning the support connecting plate 2222. The magnet lower end plate 111 is provided with a bolt hole in the support positioning groove 1111 for fixing the support connecting plate 2222.

[0045] After the magnet assembly base 2 is installed, hoisting blocks are installed at both ends of the room temperature outer cylinder 131, and the nuclear magnetic resonance instrument is hoisted and rotated 90 degrees using auxiliary rework equipment.

[0046] Reference Figure 5 The auxiliary rework equipment includes a traveling crane mechanism 3, a placing mechanism 4 and a dismantling mechanism 5. The traveling crane mechanism 3 includes a traveling crane support frame 31, a lifting assembly 32 slidably mounted on the traveling crane support frame 31, and a traveling assembly 33 that drives the lifting assembly 32 to move. The traveling crane support frame 31 includes a vertical frame 311 fixed vertically on both sides and a horizontal frame 312 mounted on the two vertical frames 311. The lifting assembly 32 is fixed on the horizontal frame 312, which includes a lifting frame 321, a first winding mechanism 322 and a second winding mechanism 323. The traveling assembly 33 includes a first walking member 331 for driving the horizontal frame 312 to slide and a second walking member 332 for driving the lifting frame 321 to slide. The sliding directions of the horizontal frame 312 and the lifting frame 321 are perpendicular. The first traveler 331 is a conventional linear drive module, used to drive the horizontal frame 312 to slide along the top of the vertical frame 311. The second traveler 332 is driven by a roller gear, used to drive the lifting frame 321 to slide along the length of the horizontal frame 312. The removal mechanism 5 is a third winding mechanism installed on the horizontal frame 312. The output shaft of the third winding mechanism is equipped with a locking clamp 51 for clamping the cold shield and inner and outer cylinder assemblies.

[0047] The first winding mechanism 322 and the second winding mechanism 323 have the same structure, both including an electric winch and a pulley set, and the first lifting hook 3221 and the second lifting hook 3231 are installed at the output ends of the electric winches of the first winding mechanism 322 and the second winding mechanism 323 respectively.

[0048] Reference Figure 6 The lifting blocks include a first lifting block 136 and a second lifting block 137. The first lifting block 136 is fixed to the side of the room temperature outer cylinder 131 facing the magnet assembly base 2. The first lifting block 136 is fixed to the top of the room temperature outer cylinder 131 by bolts. To improve the stability of the lifting, two first lifting blocks 136 are installed on the room temperature outer cylinder 131, and the two first lifting blocks 136 are symmetrically arranged along the axis of the room temperature outer cylinder 131.

[0049] The second lifting block 137 is slidably mounted on the room-temperature upper end plate 134 on the other side of the room-temperature outer cylinder 131. The end surface of the room-temperature upper end plate 134 has an arcuate rotation groove 1341 for the two second lifting blocks 137 to slide separately. The arcuate rotation groove 1341 is symmetrically arranged along the axis of the room-temperature outer cylinder 131. The room-temperature upper end plate 134 is equipped with locking members 16 at both the upper and lower ends of the arcuate rotation groove 1341 for locking the second lifting block 137. Under the action of the two locking members 16, the second lifting block 137 has two installation states. When the second lifting block 137 is fixed to the top locking member 16, the second lifting block 137 and the first lifting block 136 are at the same height, which facilitates the lifting assembly 32 to smoothly lift the nuclear magnetic resonance imager. When the second lifting block 137 is fixed to the bottom locking member 16, the height of the second lifting block 137 and the lifting block are staggered, which facilitates the two sets of winding mechanisms to rotate the nuclear magnetic resonance imager.

[0050] Locking member 16 comprises an L-shaped plate secured to room-temperature outer cylinder 131 and a set of positioning bolts mounted on the L-shaped plate. The end surface of second hoisting block 137 is provided with hoisting holes 1371 and fixing holes 1372 along its length. Hoisting holes 1371 are used for hoisting with second lifting hook 3231, while fixing holes 1372 are used for securing with positioning bolts 162.

[0051] Reference Figure 6 and Figure 7 The second lifting block 137 is integrally provided with a sliding portion 1373 for cooperating with the arc-shaped rotating groove 1341. The sliding portion 1373 is an arc-shaped block, and a pulley is installed on the side facing the bottom wall of the arc-shaped rotating groove 1341 to improve the sliding smoothness of the sliding portion 1373 in the arc-shaped rotating groove 1341.

[0052] A plunger 1342 is mounted on the top inner wall of the arcuate rotation groove 1341 of the room temperature upper end plate 134. Locking holes 13731 are provided on opposite side walls of the sliding portion 1373 to engage with the plunger 1342. The engagement of the plunger 1342 and the locking holes 13731 ensures the initial positioning of the sliding portion 1373 and the room temperature upper end plate 134, preventing the sliding portion 1373 from sliding to the bottom of the arcuate rotation groove 1341 due to gravity.

[0053] The plunger assembly 1342 comprises a plunger housing, a plunger spring, and a plunger locking block. The inner wall of the arcuate rotation slot 1341 has mounting side grooves for securing the plunger housing. The plunger spring is secured to the inner wall of the plunger housing and the plunger locking block at both ends, respectively. The plunger locking block is rectangular in shape, with a guide slope 13421 on the side facing away from the top of the arcuate rotation slot 1341.

[0054] To unlock the sliding portion 1373 and the plunger 1342, an unlocking block 1374 is mounted on the sliding portion 1373. The sliding direction of the unlocking block 1374 is parallel to the sliding direction of the plunger locking block, that is, the unlocking block 1374 slides in the radial direction of the upper end plate 134 at room temperature. The unlocking block 1374 is located on the inner wall of the locking hole 13731 facing the top of the arcuate rotation groove 1341. When the unlocking block 1374 slides away from the plunger locking block, the inner wall of the locking hole 13731 facing the arcuate rotation groove 1341 changes from a closed state to an open state, allowing the sliding portion 1373 to slide directly to the bottom of the arcuate rotation groove 1341.

[0055] The sliding portion 1373 has a fixed plate 1375 between the two unlocking blocks 1374, and the fixed plate 1375 and the unlocking block 1374 are connected by an elastic member. The elastic member can be a spring, a shrapnel, etc. The unlocking block 1374 has a driving rod 1376 extending to the outside of the upper end plate 134 at room temperature, and the sliding portion 1373 has a sliding groove for the driving rod to slide. A limiting block 1377 is installed on the end surface of the sliding portion 1373 away from the bottom wall of the arc-shaped rotating groove 1341. The limiting block 1377 can limit the sliding of the driving rod 1376, so that when the sliding portion 1373 and the plunger 1342 are normally locked and matched, the limiting block 1377 limits the sliding of the driving rod 1376.

[0056] Reference Figure 5 and Figure 9 The placement mechanism 4 includes a placement frame 41 and an auxiliary frame 42. The auxiliary frame 42 is rotatably mounted on the placement frame 41 and is used to position and place the room-temperature cylinder assembly 13. The auxiliary frame 42 has an arcuate placement groove 421 that mates with the room-temperature outer cylinder 131. The auxiliary frame 42 also has a positioning through-hole 422 formed on the bottom wall of the arcuate placement groove 421 for the outer cylinder support 135 to pass through.

[0057] The lifting assembly 32 hoists the nuclear magnetic resonance apparatus on the auxiliary frame 42, then adjusts the position of the second hoisting block 137, and then hoists and rotates the nuclear magnetic resonance apparatus so that the nuclear magnetic resonance apparatus switches from a horizontal state to a vertical state. When the nuclear magnetic resonance apparatus switches to a vertical state, there is still a gap between the magnet assembly base 2 and the bottom surface.

[0058] The placement frame 41 includes a fixed frame 411 and an elevating frame 412 that is slidably mounted on the fixed frame 411. The auxiliary frame 42 has cylindrical rotating portions 423 on opposite sides. The elevating frame 412 has a rotating slot 4121 for the rotating portion 423 to rotatably mount. The top of the rotating slot 4121 is open.

[0059] Reference Figure 9 and Figure 10 The lifting frame 412 is sleeved on the fixed frame 411, and the two are connected by multiple sets of compression springs. The top ends of the fixed frame 411 are provided with locking protrusions 4111, and the lifting frame 412 has a plug-in through hole that plugs into the locking protrusions 4111.

[0060] Combine Figure 10 Arc-shaped driving portions 424 are provided on opposite sides of the rotating portion 423. First slide posts 4122 are slidably mounted within the lifting frame 412, abutting against the arc-shaped driving portions 424. Two sets of second slide posts 4123 are slidably mounted on the lifting frame 412 on the side of the first slide posts 4122 away from the arc-shaped driving portions 424. Springs are sleeved around the outer sides of the first and second slide posts 4122, 4123 for elastic return.

[0061] The second slide post 4123 corresponds to the locking protrusion 4111. The locking protrusion 4111 has a sliding cavity 4112 extending through both end surfaces and adapted to receive the second slide post 4123. The second slide post 4123 is partially located in the sliding cavity 4112, while the other portion is located within the lifting frame 412. The cooperation between the second slide post 4123 and the locking protrusion 4111 locks the lifting frame 412 and the fixed frame 411. In this locked state, the lifting frame 412 cannot be raised or lowered vertically.

[0062] The end of the first slide post 4122 is located between the two sets of second slide posts 4123. The locking protrusion 4111 has a drive socket 4113 for inserting the first slide post 4122. The drive socket 4113 is longer in height than the first slide post 4122. The end of the first slide post 4122 has a drive slope 41221 that pushes the second slide post 4123. When the first slide post 4122 is inserted into the drive socket 4113, the two sets of second slide posts 4123 move away from each other, completely disengaging the second slide posts 4123 from the sliding chamber 4112. At this point, the lifting frame 412 and the fixed frame 411 are unlocked, and the lifting frame 412 slowly descends under the weight of the MRI scanner until the magnet assembly base 2 contacts the ground.

[0063] The specific magnet repair process includes the following steps: 1) Remove the magnet cold head and service tray assembly; 2) Remove the end plate at room temperature; 3) Remove the lower end plate of the cold screen; 4) Install the magnet assembly base on the end surface of the lower end plate of the magnet; 5) Install the first and second lifting blocks, slide the second lifting block so that it is at the same height as the first lifting block, and initially fix the second lifting block with the plunger and then with the L-shaped plate bolts; 5.1) Using the auxiliary rework equipment, hoist the NMR spectrometer horizontally onto the auxiliary frame with the lifting assembly. Unlock the second hoisting block and plunger assembly, move the second hoisting block downward to the bottom of the arc-shaped rotating trough, and activate the two winding mechanisms to adjust the NMR spectrometer from horizontal to vertical. 6) After the auxiliary frame rotates, the lifting frame and the fixed frame are unlocked, and the magnet assembly base falls to the ground; 6.1) Place the machine vertically using the magnet assembly base. Remove the room temperature cylinder assembly, cold shield, and supporting inner and outer cylinder assemblies in sequence while the machine is in the vertical position. 7) After the room temperature cylinder assembly, cold screen and supporting inner and outer cylinder assemblies are removed, the cold body assembly is exposed to the outside world. The maintenance personnel check the performance of the diodes on the cold body assembly, replace the high-temperature superconducting current lead components, replace the superconducting switch, remake the superconducting joints, and perform local heat conduction enhancement treatment on the magnet.

[0064] The above are all preferred embodiments of the present application, and are not intended to limit the scope of protection of the present application. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A magnet repair process for a liquid helium-free nuclear magnetic resonance instrument, characterized in that: The method comprises the following steps: 1) removing the magnet cold head (14) and the service plate assembly (15); 2) removing the room temperature end plate (133); 3) removing the lower end plate (124) of the cold shield; 4) installing a magnet assembly base (2) on the end surface of the magnet lower end plate (111); 5) Install lifting blocks at both ends of the room temperature cylinder assembly (13), and use auxiliary repair equipment to make the entire nuclear magnetic resonance instrument be lifted and flipped 90°; 6) The nuclear magnetic resonance instrument is placed vertically through the magnet assembly base (2), and the room temperature cylinder assembly (13), the cold shield and the supporting inner and outer cylinder assemblies (12) are removed in sequence in the vertical state; 7) After the room temperature cylinder assembly (13), the cold shield and the supporting inner and outer cylinder assemblies (12) are removed, the cold body assembly (11) is exposed to the outside world. The maintenance personnel check the performance of the diodes on the cold body assembly (11), replace the high temperature superconducting current lead components, replace the superconducting switch, remake the superconducting joints, and perform local heat conduction enhancement treatment on the magnet.

2. The magnet repair process of a liquid helium-free nuclear magnetic resonance instrument according to claim 1, characterized in that: The auxiliary rework equipment comprises a traveling crane mechanism (3), a placement mechanism (4) for installing a nuclear magnetic resonance apparatus, and a removal mechanism (5) installed on the traveling crane mechanism (3); the traveling crane mechanism (3) comprises a traveling crane support frame (31), a lifting component (32) slidably installed on the traveling crane support frame (31), and a walking component (33) driving the lifting component (32) to slide along the length direction of the traveling crane support frame (31).

3. The magnet repair process for a liquid helium-free nuclear magnetic resonance instrument according to claim 2, characterized in that: The lifting assembly (32) comprises a lifting frame (321) and a first winding mechanism (322) and a second winding mechanism (323) arranged on the lifting frame (321); the first winding mechanism (322) is provided with a first lifting hook (3221), and the second winding mechanism (323) is provided with a second lifting hook (3231); a first lifting block (136) which is fixedly matched with the first lifting hook (3221) is provided at one end of the room temperature cylinder assembly (13), and a second lifting block (137) which is fixedly matched with the second lifting hook (3231) is provided at the other end of the room temperature cylinder.

4. The magnet repair process for a liquid helium-free nuclear magnetic resonance instrument according to claim 3, characterized in that: The first lifting block (136) is located on one side of the room temperature lower end plate (133), and the second lifting block (137) is located on one side of the room temperature upper end plate (134); the second lifting block (137) is slidably mounted on the room temperature upper end plate (134), an arc-shaped rotation groove (1341) is provided on an end surface of the room temperature upper end plate (134), and locking members (16) for locking the second lifting block (137) are provided at both ends of the arc-shaped rotation groove (1341); The locking member (16) comprises an L-shaped plate fixed to the room temperature cylinder assembly (13) and a positioning bolt group installed on the L-shaped plate, and the end surface of the second lifting block (137) is provided with a lifting hole (1371) for lifting and a fixing hole (1372) for cooperating with the positioning bolt group.

5. The magnet repair process of a liquid helium-free nuclear magnetic resonance instrument (1) according to claim 4, characterized in that: The second lifting block (137) is provided with a sliding portion (1373) matched with the arc-shaped rotating groove (1341), the side wall of the sliding portion (1373) is provided with a pulley member abutting against the inner wall of the arc-shaped rotating groove (1341), the end side walls of the arc-shaped rotating groove (1341) are provided with a plunger member (1342), and the sliding portion (1373) is provided with a locking hole (13731) that is locked and matched with the plunger member (1342); The plunger member (1342) comprises a plunger housing, a plunger spring and a plunger locking block, and a side wall of the plunger locking block is provided with a guide inclined surface (13421) for the sliding portion (1373) to abut against.

6. The magnet repair process of a liquid helium-free nuclear magnetic resonance instrument (1) according to claim 5, characterized in that: An unlocking block (1374) is slidably installed on the sliding portion (1373), and the sliding direction of the unlocking block (1374) is parallel to the moving direction of the plunger locking block. The unlocking block (1374) is the inner wall of the locking hole (13731) facing the top of the arc-shaped rotating groove (1341). When the unlocking block (1374) slides, the side wall of the locking hole (13731) facing the top of the arc-shaped rotating groove (1341) is adjusted from a closed state to an open state.

7. The magnet repair process of a liquid helium-free nuclear magnetic resonance instrument (1) according to claim 1, characterized in that: The placement mechanism (4) comprises a placement frame (41) and an auxiliary frame (42) rotatably mounted on the placement frame (41) and for placing the room temperature cylinder, the auxiliary frame (42) having an arc-shaped placement groove (421) matched with the side wall of the room temperature cylinder assembly (13), and a positioning through hole (422) is provided on the bottom wall of the arc-shaped placement groove (421), the room temperature cylinder assembly (13) having an outer cylinder support (135) passing through the positioning through hole (422), and when the lifting assembly (32) rotates the auxiliary frame (42) to a vertical state, there is a gap between the bottom of the magnet assembly base (2) and the ground.

8. The magnet repair process of a liquid helium-free nuclear magnetic resonance instrument (1) according to claim 7, characterized in that: The auxiliary frame (42) is provided with rotating parts (423) on opposite sides thereof, the placement frame (41) comprises a fixed frame (411) and a lifting frame (412) installed on the fixed frame (411) in a lifting manner, the lifting frame (412) having a rotating groove (4121) for installing the rotating part (423), and the top of the rotating groove (4121) is open; Arc-shaped driving parts (424) are arranged on both sides of the rotating part (423); a first sliding post (4122) for abutting against the arc-shaped driving part (424) is slidably installed in the lifting frame body (412); two second sliding posts (4123) are slidably installed on the lifting frame body (412) at one end of the first sliding post (4122) away from the arc-shaped driving part (424); a locking protrusion (4111) is arranged on the top of the placement frame body (41); the locking protrusion (4111) is provided with a sliding chamber (4112) for installing the second sliding post (4123); the locking protrusion (4111) and the lifting frame body (412) are plug-fitted; When the rotating part (423) rotates 90 degrees, the rotating part (423) drives the first sliding post (4122) to slide, and the first sliding post (4122) drives the second sliding post (4123) to slide, so that the second sliding post (4123) is separated from the sliding chamber (4112), and the lifting frame (412) and the placement frame (41) are unlocked.

9. The magnet repair process of a liquid helium-free nuclear magnetic resonance instrument (1) according to claim 3, characterized in that: The dismantling mechanism (5) is a third winding mechanism arranged on the traveling hoist mechanism (3), and the lifting hook of the third winding mechanism is provided with a locking clamp (51) for locking the cold screen and supporting the inner and outer cylinder assemblies (12).

10. The magnet repair process of a liquid helium-free nuclear magnetic resonance instrument (1) according to claim 1, characterized in that: The magnet assembly base (2) comprises a magnet support base frame (21) fixed to the magnet lower end plate (111) and a plurality of groups of magnet support wheels (22) arranged on the magnet support base frame (21); the magnet support frame is provided with a support connecting plate (2222) for fitting with the magnet lower end plate (111); the magnet lower end plate (111) is provided with a support positioning groove (1111) for positioning the support connecting plate (2222); and the support positioning groove (1111) is provided with a bolt hole for fixing with the support connecting plate (2222).

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