Magnet position adjusting device and method in a high magnetic field environment

Abstract

This invention discloses a magnet position adjustment device and method under a strong magnetic field environment, including magnet feet, inclined support blocks, rolling rods, and height adjustment mechanisms. Four magnet feet are evenly distributed at the four corners of the magnet's bottom, with the bottom surface of each foot forming a horizontal support surface. Four height adjustment mechanisms are also provided, each connected to a magnet foot, for raising and lowering the magnet as a whole. Each magnet foot has a pair of inclined support blocks and rolling rods below it. The inclined support blocks are wedge-shaped and positioned below the magnet feet, with their top surfaces being inclined. The rolling rods are cylindrical and positioned between the inclined support blocks and the magnet feet, transmitting the magnet's weight load. When the magnet descends via the height adjustment mechanisms, the magnet feet press against the rolling rods, causing them to slide along the inclined surfaces of the inclined support blocks, thereby moving the magnet horizontally along the inclined surfaces. This invention is safe and convenient to operate, enabling smooth, controllable, and high-precision position adjustment during magnet movement, effectively preventing impact damage to precision magnets.

Description

Technical Field

[0001] This invention relates to the field of positioning and installation technology for large precision equipment, specifically to a magnet position adjustment device and method under a strong magnetic field environment. Background Technology

[0002] Magnetic resonance imaging (MRI) equipment is a key device in modern medical diagnostics, and its core component is a superconducting magnet. This magnet, in its superconducting state (usually immersed in liquid helium at a temperature below 4K), generates a stable, high-intensity magnetic field (such as 1.5T, 3.0T, 5.0T, or higher) when a powerful current (hundreds of amperes) is passed through it. The strong magnetic field of the superconducting magnet exerts a tremendous attraction on ferromagnetic materials. Once a ferromagnetic object (such as a conventional tool) is attracted, it can not only damage the expensive internal precision structure of the magnet (such as the carbon fiber suspension system) but also cause serious injury to personnel on site. Larger ferromagnetic tools, once attracted, often require an emergency de-fielding procedure called "quenching," which results in the evaporation of a large amount of liquid helium and carries the risk of equipment failure. The superconducting magnet itself weighs approximately 6 tons; with the gradient coil, radio frequency coil, and casing, the total weight can exceed 7 tons.

[0003] The magnet must be precisely positioned during installation to ensure perfect interface with subsystems such as the quench tube and hospital bed. Any deviation in installation location (such as incorrect shielded room planning, or misalignment of the hospital bed's anchor bolts) and positional deviation caused during use (such as magnet displacement due to improper replacement of magnet vibration damping pads) necessitates appropriate adjustment of the magnet's position. Currently, the standard and only procedure for adjusting the position of a magnet that has been raised to a high magnetic field (i.e., in a strong magnetic field state) within a hospital's shielded room is as follows: S1. Lowering the field (quenching): First, perform an active quenching operation on the magnet to reduce its internal magnetic field to near zero; S2. Adjusting with heavy tools: After the magnetic field disappears, use heavy-duty transport tools such as large ground tanks and jacks to move the several-ton magnet to the target position; S3. Raising the field again: After the position adjustment is completed, perform a field raising operation on the magnet again to restore it to the working field strength. This solution relies on specialized lifting equipment and heavy-duty handling equipment. The process is complex and requires operation by professional personnel from the manufacturer, and it presents the following problems: 1. High economic costs and resource waste: Each lifting process results in the evaporation of approximately 100 liters of liquid helium, causing direct economic losses. Simultaneously, the specialized lifting equipment, ground tanks, jacks, etc., need to be transported from the manufacturer to the hospital, incurring high logistics and time costs. 2. High equipment risk: Magnetic lifting is not a risk-free operation; there is a certain probability of lifting failure, which may lead to permanent damage to the magnets and significant economic losses. 3. Complex operation and slow response: The entire process is time-consuming, from equipment transportation and personnel dispatch to completion of the operation. It cannot quickly respond to the fine-tuning needs at the installation site, seriously affecting the project schedule. 4. Safety hazards: Moving the precision magnets with heavy equipment after lowering them carries the risk of damage due to impact caused by improper operation. Summary of the Invention

[0004] To address the shortcomings of the prior art, this invention provides a magnet position adjustment device and method in a strong magnetic field environment, avoiding the need for lifting and lowering field operations and achieving stable and controllable movement of the magnet.

[0005] To achieve the above-mentioned technical objectives, the technical solution adopted by the present invention is as follows:

[0006] A magnet position adjustment device for a strong magnetic field environment includes magnet feet, inclined support blocks, rolling rods, and height adjustment mechanisms. Four magnet feet are evenly distributed at the four corners of the magnet's bottom, with the bottom surface of each foot forming a horizontal support surface. Four height adjustment mechanisms are connected to the magnet feet for raising and lowering the magnet as a whole. Each magnet foot has a pair of inclined support blocks and rolling rods below it. The inclined support blocks are wedge-shaped and positioned below the magnet feet, with their top surfaces being inclined. The rolling rods are cylindrical and positioned between the inclined support blocks and the magnet feet, transmitting the magnet's weight load. When the magnet descends via the height adjustment mechanisms, the magnet feet press against the rolling rods, causing them to slide along the inclined surfaces of the inclined support blocks, thereby moving the magnet horizontally along the inclined surfaces.

[0007] As a preferred technical solution, the height adjustment mechanism includes a mounting bracket, a trapezoidal lead screw assembly, a drive component, and a lead screw support plate. The mounting bracket is fixedly installed on the side wall of the magnet base. The nut of the trapezoidal lead screw assembly is vertically axially installed and embedded in the mounting bracket, and the trapezoidal lead screw is threadedly connected to the nut. The lead screw support plate is placed on the supporting ground, and a countersunk hole is opened on the top surface. The outer circumference of the countersunk hole is adapted to the lower part of the trapezoidal lead screw. The bottom of the trapezoidal lead screw abuts against the countersunk hole of the lead screw support plate, and the top of the trapezoidal lead screw is connected to the drive component.

[0008] As a preferred technical solution, the inclined support block and the rolling rod are both made of 304 austenitic stainless steel.

[0009] As a preferred technical solution, the inclination angle of the top surface of the inclined support block is 3~8°.

[0010] As a preferred technical solution, the inclination angle of the top surface of the inclined support block is 5°.

[0011] As a preferred technical solution, the driving component is a driving swing arm.

[0012] As a preferred technical solution, the driving component is bonded to the trapezoidal lead screw.

[0013] As a preferred technical solution, one end of the drive swing arm is a connecting end, and the connecting end is provided with a square connecting hole. The top of the trapezoidal lead screw is provided with a square column, and the connecting hole is adapted to the square column.

[0014] As a preferred technical solution, the mounting bracket, trapezoidal lead screw, driving component, and lead screw support plate are made of 304 austenitic stainless steel.

[0015] A method for adjusting the position of a magnet in a strong magnetic field environment, using the aforementioned magnet position adjustment device for a strong magnetic field environment, includes the following steps:

[0016] S1. Initial positioning: Screw the trapezoidal lead screw into the nut and fix the mounting bracket to the magnet foot with screws; fix the lead screw support plate to the supporting ground and adjust the lower end of the trapezoidal lead screw to fall into the countersunk hole of the lead screw support plate;

[0017] S2. Magnet Lifting: The four drive components rotate synchronously, driving the trapezoidal lead screw to rotate and extend axially, thus lifting the magnet.

[0018] S3. Arrangement of inclined support block and rolling rod: According to the calibrated moving direction, place the inclined surface of the inclined support block towards the target direction; push the rolling rod along the inclined surface into the V-shaped space formed by the inclined support block and the magnet foot;

[0019] S4. Horizontal movement control: Slowly reverse the drive mechanism to retract the trapezoidal lead screw, transferring the weight of the magnet to the rolling rod. The magnet slides along the inclined plane towards the target direction while its height decreases. When the end of the trapezoidal lead screw contacts the countersunk hole of the lead screw support plate, the weight of the magnet is again borne by the trapezoidal lead screw assembly. Continue to slowly reverse the drive mechanism, and the magnet continues to descend and move towards the target position. Stop reversing the drive mechanism when the target position is reached.

[0020] S5. Determine if the position is in place and whether repeated adjustment and synchronization control are needed: If the magnet has not reached the target position when the rolling rod reaches the bottom of the inclined support block, repeat steps S2 to S4 until the target position is reached.

[0021] S6. Final Positioning and Unloading: After the movement is completed, rotate the four drive components to lift the magnet, remove the inclined support block and rolling rod, and install the vibration damping pad; lower the magnet to press it against the vibration damping pad, retract the trapezoidal lead screw, disassemble the mounting bracket and lead screw support plate, and the adjustment is complete.

[0022] The beneficial effects of this invention are:

[0023] 1. The device and method of the present invention achieve field-free adjustment: allowing the magnet to be precisely adjusted in position while maintaining the working field strength (strong magnetic field environment), completely avoiding the operation of raising and lowering the magnet field, fundamentally eliminating the resulting liquid helium loss (saving about 100 liters each time) and the risk of magnet field raising failure, greatly improving economic benefits and equipment safety; saving expensive special equipment transportation costs and equipment waiting time costs, with outstanding overall economic benefits.

[0024] 2. The device and method of the present invention ensure smooth and precise adjustment: Based on the combination of inclined support rod, rolling rod and trapezoidal lead screw assembly, a controllable and smooth movement mechanism is provided, which can precisely control the direction and distance of magnet movement and avoid any impact or damage to precision magnet.

[0025] 3. The device and method of the present invention enable non-magnetic manual operation, which is safe and convenient: the entire set of adjustment fixtures is made entirely of non-magnetic or weakly magnetic materials, and can be safely operated manually by installation personnel or after-sales service personnel in a shielded room, without the need to introduce any ferromagnetic tools or large power equipment. Manual operation is simple and intuitive, requiring no professional lifting equipment or heavy tools, and has a fast response speed, greatly improving installation and commissioning efficiency. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is an overall schematic diagram of the device of the present invention;

[0028] Figure 2 yes Figure 1 Enlarged view of the area within the dashed box;

[0029] Figure 3 This is a front view of the device of the present invention;

[0030] Figure 4 yes Figure 3 Enlarged view of the area within the dashed box;

[0031] Figure 5 This is a top view of the magnet base arrangement;

[0032] Figure 6 This is a cross-sectional view of a trapezoidal lead screw;

[0033] Figure 7 This is a sectional view of the lead screw support plate;

[0034] Figure 8 This is a flowchart illustrating the method of the present invention.

[0035] Icons: 1-Magnet, 2-Magnet foot, 3-Angled support block, 4-Rolling rod, 5-Mounting bracket, 6-Trapezoidal screw, 7-Drive component, 8-Screw support plate, 81-Sunk hole, 9-Supporting ground. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0037] A magnet position adjustment device in a strong magnetic field environment, such as Figures 1-7 As shown, the device includes magnet feet 2, inclined support blocks 3, rolling rods 4, and a height adjustment mechanism. Four magnet feet 2 are evenly distributed at the four corners of the bottom of the magnet 1, and the bottom surface of each magnet foot 2 is a horizontal support surface. Four height adjustment mechanisms are connected to the magnet feet 2 respectively, used for raising and lowering the magnet 1 as a whole. Each magnet foot 2 is equipped with a pair of inclined support blocks 3 and rolling rods 4 below it. The inclined support blocks 3 are wedge-shaped and positioned below the magnet feet 2, with their top surfaces being inclined. The rolling rods 4 are cylindrical and positioned between the inclined support blocks 3 and the magnet feet 2, transmitting the weight load of the magnet. When the magnet 1 descends via the height adjustment mechanism, the magnet feet 2 press against the rolling rods 4, causing the rolling rods 4 to slide along the inclined surface of the inclined support blocks 3, thereby driving the magnet 1 to move horizontally along the inclined surface.

[0038] Preferably, the inclined support block 3 and the rolling rod 4 are both made of 304 austenitic stainless steel. The inclination angle of the top surface of the inclined support block 3 is 3~8°. Specifically, the inclination angle of the top surface of the inclined support block 3 can be 3°, 5°, 6°, or 8°. The rolling rod, inclined support block, and magnet feet that are in contact with each other are all made of 304 austenitic stainless steel. The rolling friction coefficient μ of this material combination in the unlubricated state is usually between 0.005 and 0.01. The inclination angle of the top surface of the inclined support block 3 is much larger than the theoretical rolling friction angle, which can ensure that the magnet can overcome the rolling resistance and slide smoothly under the action of the gravity component. At the same time, the angle itself is small, which is conducive to achieving precise displacement control. Preferably, the inclined support block 3 and the rolling rod 4 are provided with handles on the side for easy handling and hand-held orientation adjustment.

[0039] In one specific embodiment, the height adjustment mechanism includes a mounting bracket 5, a trapezoidal lead screw assembly, a drive component 7, and a lead screw support plate 8. The mounting bracket 5 is fixedly mounted on the side wall of the magnet base 2. The nut of the trapezoidal lead screw assembly is vertically axially positioned and embedded in the mounting bracket 5, and the trapezoidal lead screw 6 is threadedly connected to the nut. The lead screw support plate 8 rests on the supporting ground 9, and a countersunk hole 81 is formed on its top surface. The outer circumference of the countersunk hole 81 is adapted to the lower part of the trapezoidal lead screw 6. The bottom of the trapezoidal lead screw 6 abuts against the countersunk hole of the lead screw support plate 8, and the top of the trapezoidal lead screw 6 is connected to the drive component 7. By rotating the drive component 7, the trapezoidal lead screw 6 is rotated, which in turn drives the mounting bracket 5, the magnet base 2, and the magnet 1 to rise and fall via the nut.

[0040] Preferably, the lower part of the trapezoidal lead screw 6 is cylindrical, and the bottom end face is convex arc-shaped to reduce friction between the trapezoidal lead screw and the lead screw support plate. The driving component 7 is keyed to the trapezoidal lead screw 6. In a preferred embodiment, the driving component 7 is a driving swing arm, one end of which is a connecting end with a square connecting hole. The top of the trapezoidal lead screw 6 has a square post, and the connecting hole matches the square post. The driving swing arm has a relatively long lever arm, which ensures easy operation and meets the condition of "human-powered drive". Of course, the driving component 7 can also be a handwheel.

[0041] Preferably, the mounting bracket 5, trapezoidal lead screw 6, driving component 7, and lead screw support plate 8 are made of 304 austenitic stainless steel.

[0042] The adjustment device of the present invention utilizes the self-locking characteristics of inclined plane transmission and trapezoidal screw assembly. The height of the magnet is controlled by raising and lowering the trapezoidal screw assembly, so that the weight of the magnet is transferred between the rolling rod pressing on the inclined plane support block and the support between the trapezoidal screw, thereby achieving precise horizontal displacement.

[0043] This invention controls the height of a magnet using a trapezoidal lead screw assembly. The magnet's weight, acting as a component on an inclined plane, drives its horizontal movement, converting manual rotation into smooth, precise, and directionally controllable horizontal movement. It also ensures the magnet can self-lock at any desired position. The horizontal displacement is precisely adjusted by controlling the number of rotations of the trapezoidal lead screw, supporting independent operation of each support point to achieve translation or in-plane rotation of the magnet. Precise adjustment of the overall magnet's posture (position and orientation) is achieved by independently controlling the displacement and direction of the devices at each support point (magnet's feet). The trapezoidal lead screw has a self-locking characteristic, ensuring the magnet's position remains stable during adjustment, preventing accidental slippage, and guaranteeing operator safety. All components are made of non-magnetic materials such as 304 stainless steel, ensuring normal operation of the fixture in strong magnetic field environments.

[0044] Specific adjustment methods are as follows Figure 8 As shown, the steps include:

[0045] S1, Initial Positioning

[0046] Screw the trapezoidal lead screw 6 into the nut and fix the mounting bracket to the magnet foot 2 with screws; fix the lead screw support plate 8 to the supporting ground 9 and adjust the lower end of the trapezoidal lead screw 6 into the countersunk hole 81 of the lead screw support plate 8.

[0047] S2, Magnet Lifting

[0048] The operator rotates the four drive components 7 in sync, causing the trapezoidal lead screw 6 to rotate and extend axially relative to the nut, thus lifting the magnet. The lifting height is determined by ensuring that the inclined support block 3 and the rolling rod 4 can be smoothly placed under the magnet's feet.

[0049] S3. Arrangement of inclined support block and rolling rod

[0050] According to the calibrated direction of movement, place the inclined surface of the inclined support block 3 toward the target direction; push the rolling rod 4 along the inclined surface into the V-shaped space formed by the inclined support block 3 and the magnet foot 2 to prevent slippage.

[0051] S4, Horizontal Movement Control

[0052] Slowly reverse the drive component 7 to retract the trapezoidal lead screw 6, transferring the weight of the magnet to the rolling rod 4 (the bottom end face of the trapezoidal lead screw 6 leaves the bottom surface of the recessed hole 81, keeping the bottom of the trapezoidal lead screw 6 still within the recessed hole 81); since the inclination angle of the inclined plane is greater than the rolling friction angle, the magnet slides along the inclined plane in the target direction (the magnet drives the trapezoidal lead screw to move together, and since the trapezoidal lead screw has not detached from the lead screw support plate, it drives the lead screw support plate to move together), while the height decreases slightly; when the lower end of the trapezoidal lead screw 6 contacts the bottom surface of the recessed hole of the lead screw support plate 8, the weight of the magnet is again borne by the trapezoidal lead screw assembly, and the movement stops; if the target position is not reached, continue to slowly reverse the drive component, and the magnet continues to descend and move towards the target position, stopping when the target position is reached.

[0053] S5. Determine if the position is in place and whether repeated adjustments and synchronization control are needed.

[0054] If the magnet has not reached the target position when the rolling rod 4 reaches the bottom of the inclined plane of the inclined support block 3, and needs to continue moving, then repeat steps S2 to S4 until the target position is reached.

[0055] If only some magnet feet need to be adjusted, the magnet feet that do not need to be adjusted should be kept raised and their height adjusted together with the other magnet feet to keep the magnets level. However, there is no need to place inclined support blocks and rolling rods under the magnet feet.

[0056] S6. Final Location and Uninstallation

[0057] After the movement is complete, raise the magnet again, remove the inclined support block 3 and the rolling rod 4, and install the vibration damping pad. Lower the magnet 1 to press it against the vibration damping pad, retract the trapezoidal lead screw 6, disassemble the mounting bracket and lead screw support plate, and the adjustment is complete.

[0058] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the appended claims.

Claims

1. A magnet position adjustment device under a strong magnetic field environment, characterized in that: It includes magnet feet, inclined support blocks, rolling rods, and height adjustment mechanisms; there are four magnet feet, evenly distributed at the four corners of the bottom of the magnet, and the bottom surface of the magnet feet is a horizontal support surface; there are four height adjustment mechanisms, each connected to a magnet foot, for raising and lowering the magnet as a whole. Each magnet's base is equipped with a pair of inclined support blocks and a rolling rod. The inclined support blocks are wedge-shaped and positioned below the magnet's base, with their top surfaces inclined at an angle of 3-8°. The rolling rods are cylindrical and positioned between the inclined support blocks and the magnet's base to transmit the magnet's weight load. When the magnet descends via the height adjustment mechanism, the magnet's base presses against the rolling rods, causing them to slide along the inclined surfaces of the support blocks, thereby driving the magnet to move horizontally along the inclined surfaces. The height adjustment mechanism includes a mounting bracket, a trapezoidal lead screw assembly, a drive component, and a lead screw support plate. The mounting bracket is fixedly mounted on the side wall of the magnet's base. The nut of the trapezoidal lead screw assembly is vertically axially positioned and embedded in the mounting bracket, with the trapezoidal lead screw and nut threadedly connected. The lead screw support plate is placed on the supporting ground, with a countersunk hole on its top surface. The outer circumference of the countersunk hole is adapted to the lower part of the trapezoidal lead screw. The bottom of the trapezoidal lead screw abuts against the countersunk hole of the lead screw support plate, and the top of the trapezoidal lead screw is connected to the drive component.

2. The magnet position adjustment device under a strong magnetic field environment according to claim 1, characterized in that: The inclined support block and rolling rod are both made of 304 austenitic stainless steel.

3. The magnet position adjustment device under a strong magnetic field environment according to claim 1, characterized in that: The inclination angle of the top surface of the inclined support block is 5°.

4. The magnet position adjustment device under a strong magnetic field environment according to claim 1, characterized in that: The driving component is a driving swing arm.

5. The magnet position adjustment device under a strong magnetic field environment according to claim 4, characterized in that: The drive component is bonded to the trapezoidal lead screw.

6. The magnet position adjustment device under a strong magnetic field environment according to claim 5, characterized in that: One end of the drive swing arm is a connecting end, and the connecting end is provided with a square connecting hole. The top of the trapezoidal lead screw is provided with a square column, and the connecting hole is adapted to the square column.

7. The magnet position adjustment device under a strong magnetic field environment according to claim 1, characterized in that: The mounting bracket, trapezoidal lead screw, drive component, and lead screw support plate are made of 304 austenitic stainless steel.

8. A method for adjusting the position of a magnet in a strong magnetic field environment, characterized in that: Using the magnet position adjustment device in a strong magnetic field environment as described in any one of claims 1 to 7, the steps include: S1. Initial positioning: Screw the trapezoidal lead screw into the nut and fix the mounting bracket to the magnet foot with screws; fix the lead screw support plate to the supporting ground and adjust the lower end of the trapezoidal lead screw to fall into the countersunk hole of the lead screw support plate; S2. Magnet Lifting: The four drive components rotate synchronously, driving the trapezoidal lead screw to rotate and extend axially, thus lifting the magnet. S3. Arrangement of inclined support block and rolling rod: According to the calibrated moving direction, place the inclined surface of the inclined support block towards the target direction; push the rolling rod along the inclined surface into the V-shaped space formed by the inclined support block and the magnet foot; S4. Horizontal movement control: Slowly reverse the drive mechanism to retract the trapezoidal lead screw, transferring the weight of the magnet to the rolling rod. The magnet slides along the inclined plane towards the target direction while its height decreases. When the end of the trapezoidal lead screw contacts the countersunk hole of the lead screw support plate, the weight of the magnet is again borne by the trapezoidal lead screw assembly. Continue to slowly reverse the drive mechanism, and the magnet continues to descend and move towards the target position. Stop reversing the drive mechanism when the target position is reached. S5. Determine if the position is in place and whether repeated adjustment and synchronization control are needed: If the magnet has not reached the target position when the rolling rod reaches the bottom of the inclined support block, repeat steps S2 to S4 until the target position is reached. S6. Final Positioning and Unloading: After the movement is completed, rotate the four drive components to lift the magnet, remove the inclined support block and rolling rod, and install the vibration damping pad; lower the magnet to press it against the vibration damping pad, retract the trapezoidal lead screw, disassemble the mounting bracket and lead screw support plate, and the adjustment is complete.

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