Gradient shimming device

Abstract

The utility model discloses a gradient shimming device, which relates to the technical field of magnetic resonance imaging and comprises a magnet, a support, a plurality of shimming strips and a plurality of drivers. A plurality of shimming grooves in which all the shimming strips can be inserted in a one-to-one correspondence manner are formed in the magnet; all the drivers are connected with all the shimming strips in a one-to-one correspondence mode and used for driving the shimming strips to move relative to the shimming grooves in a pluggable mode. All the drivers are arranged on the support. The gradient shimming device can automatically insert and pull out shimming strips and effectively position the shimming strips. According to the gradient shimming device, when the shimming strips are automatically inserted and pulled through the multiple drivers, the moving difficulty of the shimming strips in the magnetic field environment can be reduced, the multiple shimming strips can enter and exit from the shimming grooves at the same time, the workload of operators is reduced, and the shimming strips can be frequently inserted and pulled to debug the shimming strips and shimming pieces of the shimming strips.

Description

Technical Field

[0001] The utility model relates to the technical field of magnetic resonance imaging, in particular to a gradient shimming device. Background Art

[0002] The magnetic resonance system requires a magnet to generate a highly uniform magnetic field in the image acquisition area in order to perform magnetic resonance imaging.

[0003] Usually, the magnetic field of the magnetic resonance system needs to be corrected for magnetic field uniformity in order to obtain a magnetic resonance image with better imaging quality. Currently, a passive shimming method can be used to make the magnetic field have better magnetic field uniformity.

[0004] Passive shimming refers to installing ferromagnetic materials such as iron sheets as shims in shim bars, and then inserting multiple shim bars into the slots of the gradient coil according to the designed positions. The number and position of shims in each shim bar affect the magnetic field uniformity, which is generally measured and analyzed by a gauss meter or field strength meter.

[0005] However, the existing passive shimming method is difficult to operate and is very time-consuming. This is because the number and position of shim pieces in each shim bar require multiple tests and iterative calculations. Therefore, operators need to frequently plug and unplug the shim bars. Shim bars are difficult to move in a magnetic field, and shim bars moved out of the magnetic field require additional positioning. All of these increase the difficulty and workload of passive shimming.

[0006] In summary, how to reduce the difficulty of magnetic field uniformity correction has become an urgent problem to be solved by those skilled in the art. Utility Model Content

[0007] The utility model aims to provide a gradient shimming device which can be used for passive shimming, can automatically and efficiently plug and unplug shimming strips, reduce the difficulty of magnetic field uniformity correction, and improve the passive shimming effect.

[0008] To achieve the above-mentioned purpose, the utility model provides a gradient shimming device, comprising a magnet, a bracket, a plurality of shimming strips and a plurality of drivers; a plurality of shimming slots are arranged in the magnet for all the shimming strips to be inserted one by one; all the drivers are connected to all the shimming strips one by one and are used to drive the shimming strips to be inserted, pulled out and moved relative to the shimming slots; all the drivers are arranged on the bracket.

[0009] In some embodiments, the bracket includes a positioning plate and a positioning rod; the magnet is columnar, the axial end of the magnet is spaced parallel to the positioning plate, and the two ends of the positioning rod are respectively connected to the magnet and the positioning plate; all drivers are arranged on the positioning plate.

[0010] In some embodiments, the bracket further includes a plurality of guide rods; all guide rods correspond to all shim strips one by one, the two ends of any guide rod are respectively connected to the magnet and the positioning plate, and any shim strip is slidably mounted on the corresponding guide rod.

[0011] In some embodiments, any guide rod is provided with a lead screw and a lead screw slider provided on the lead screw; any shim bar is attached to the corresponding lead screw, and the end of any shim bar is connected to the corresponding lead screw slider.

[0012] In some embodiments, a plurality of guide rods are disposed between the magnet and the positioning disk; all guide rods are distributed in a circle around the central axis of the positioning disk, and all shim strips are disposed around the circumference of all guide rods.

[0013] In some embodiments, multiple positioning rods are provided between the magnet and the positioning plate; one end of all the positioning rods is detachably connected to the magnet, and the other end of all the positioning rods is detachably connected to the positioning plate; at least one end of all the positioning rods is provided with an elongated mounting hole extending radially along the magnet and a locking piece arranged in the elongated mounting hole.

[0014] In some embodiments, at least one end of any positioning rod is provided with an L-shaped connecting bent rod; the connecting bent rod is provided with an elongated mounting hole and a locking piece.

[0015] In some embodiments, a gradient coil is provided on the surface of the magnet; the gradient coil is provided with a plurality of gradient strip mounting holes which are aligned one by one with all the shim slots.

[0016] Compared with the above background technology, the gradient shimming device provided by the utility model includes a magnet, a bracket, a plurality of shimming strips and a plurality of drivers; a plurality of shimming slots are provided in the magnet for all shimming strips to be inserted one by one; all drivers are connected to all shimming strips one by one, and are used to drive the shimming strips to be inserted and removed relative to the shimming slots; all drivers are arranged on the bracket. The beneficial effects of the gradient shimming device are as follows:

[0017] The gradient shim device provided by the utility model can automatically insert and remove shim bars. Compared with manual insertion and removal of shim bars, it can reduce the difficulty of moving the shim bars in a magnetic field environment, and realize multiple shim bars entering and exiting the shim slot at the same time, thereby improving operating efficiency, reducing the operating burden of frequent insertion and removal of shim bars, and providing great convenience for debugging the shim bars and the shim sheets thereon. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0019] Figure 1 A schematic diagram of the structure of a gradient shimming device provided in an embodiment of the utility model;

[0020] Figure 2 This is a schematic diagram of the assembly of the shim strips, brackets and drivers provided in an embodiment of the utility model.

[0021] Among them, 1-magnet, 11-uniform field slot, 2-bracket, 21-positioning plate, 22-positioning rod, 23-guide rod, 3-uniform field bar, 4-driver, 51-lead screw, 52-lead screw slider, 6-gradient coil, 7-locking piece. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0023] In order to enable those skilled in the art to better understand the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0024] Please refer to Figure 1 and Figure 2 , Figure 1 A schematic diagram of the structure of a gradient shimming device provided in an embodiment of the utility model; Figure 2 This is a schematic diagram of the assembly of the shim strips, brackets and drivers provided in an embodiment of the utility model.

[0025] The utility model provides a gradient shimming device, comprising a magnet 1, a bracket 2, shimming strips 3 and a driver 4; in the gradient shimming device, a plurality of shimming strips 3 are arranged between the magnet 1 and the bracket 2, a plurality of shimming slots 11 are arranged in the magnet 1, all the shimming strips 3 can be plugged into all the shimming slots 11 one by one, any shimming strip 3 is connected with a corresponding driver 4, all the drivers 4 are connected to the bracket 2, any driver 4 can drive the corresponding shimming strip 3 to be plugged and pulled relative to the shimming slot 11, that is, any shimming strip 3 can be automatically pulled out from the shimming slot 11 under the action of the corresponding driver 4, and can also be automatically inserted into the shimming slot 11 under the action of the corresponding driver 4.

[0026] The gradient shimming device uses a driver 4 to manipulate the shim strips 3 to move relative to the shim slots 11, so that the shim strips 3 can be automatically inserted into and removed from the corresponding shim slots 11, without the need for manual insertion and removal by operators, thereby reducing the operator's workload.

[0027] Usually, when using a gradient shim device, it is necessary to repeatedly debug the shim bars 3 and the shim plates thereon, so it is necessary to frequently plug and unplug the shim bars 3 in the shim slot 11. The gradient shim device provided by the utility model automatically plugs and unplugs each shim bar 3 through multiple drivers 4, which not only reduces the difficulty of moving the shim bars 3 in a magnetic field environment, thereby reducing the workload of frequently plugging and unplugging the shim bars 3, providing great convenience for debugging the shim bars 3 and the shim plates thereon, but also enables multiple shim bars 3 to enter and exit the shim slot 11 at the same time, thereby improving operating efficiency.

[0028] The gradient shimming device provided by the present invention is further described below in conjunction with the accompanying drawings and implementation examples.

[0029] In some embodiments, the bracket 2 may include a positioning plate 21 and a positioning rod 22, and the magnet 1 is columnar; wherein the axial end of the magnet 1 is spaced and parallel to the positioning plate 21, and the two ends of the positioning rod 22 are respectively connected to the magnet 1 and the positioning plate 21; all drivers 4 are arranged on the positioning plate 21.

[0030] In the above embodiment, all drivers 4 are arranged on the positioning plate 21, and all shim strips 3 are between the magnet 1 and the positioning plate 21. Any driver 4 can drive the corresponding shim strip 3 to move back and forth between the magnet 1 and the positioning plate 21, so that the aforementioned shim strip 3 can be inserted into the shim slot 11 of the magnet 1 or pulled out of the shim slot 11 of the magnet 1.

[0031] For reference Figure 1 In some embodiments, the bracket 2 includes not only a positioning plate 21 and a positioning rod 22, but also a plurality of guide rods 23; wherein all guide rods 23 correspond to all uniform field strips 3 one by one, and the two ends of any guide rod 23 are respectively connected to the magnet 1 and the positioning plate 21, and any uniform field strip 3 is slidably installed on the corresponding guide rod 23.

[0032] In the above embodiment, the two ends of the guide rod 23 are respectively connected to the magnet 1 and the positioning plate 21 , which specifically means that one end of the guide rod 23 is fixed to the positioning plate 21 and the other end is against the magnet 1 .

[0033] In the above embodiment, the guide rod 23 can support the shim bar 3 and guide the movement of the shim bar 3, so that the shim bar 3 can smoothly and accurately enter and exit the shim slot 11 of the magnet 1. For example, when the shim bar 3 is completely pulled out of the shim slot 11, the guide rod 23 can ensure that the shim bar 3 is inserted into the corresponding shim slot 11 again.

[0034] For reference Figure 1 and Figure 2 Any guide rod 23 is provided with a lead screw 51 and a lead screw slider 52; the lead screw 51 is connected to the driver 4, and the lead screw slider 52 is provided on the lead screw 51. When the driver 4 is running, the lead screw slider 52 can be driven to slide along the lead screw 51. In this embodiment, any shim bar 3 is attached to the corresponding lead screw 51, and the end of any shim bar 3 is connected to the corresponding lead screw slider 52. The driver 4 can push and pull the shim bar 3 through the lead screw slider 52, so that the shim bar 3 moves along the lead screw 51, so that the shim bar 3 automatically enters and exits the shim slot 11.

[0035] In some embodiments, a plurality of guide rods 23 are provided between the magnet 1 and the positioning plate 21; Figure 1 As shown, all guide rods 23 can be distributed in a circle around the central axis of the positioning disk 21, and all shim strips 3 are arranged around the circumference of all guide rods 23. In other words, any shim strip 3 is arranged on the side of the corresponding guide rod 23 away from the central axis of the positioning disk 21, so that the operator can adjust the structural shape of the shim strip 3, such as adding or removing shim plates to the shim strip 3.

[0036] In some embodiments, a plurality of positioning rods 22 are provided between the magnet 1 and the positioning plate 21, one end of the positioning rods 22 is detachably connected to the magnet 1, and the other end of the positioning rods 22 is detachably connected to the positioning plate 21; for any one of the positioning rods 22, its end is provided with an elongated mounting hole extending radially along the magnet 1 and a locking piece 7 arranged in the elongated mounting hole, and the elongated mounting hole and the locking piece 7 are arranged at at least one end of any one of the positioning rods 22.

[0037] In the above embodiment, the end of the positioning rod 22 is provided with an elongated mounting hole and a locking member 7, and the elongated mounting hole extends in the radial direction of the magnet 1 and also in the radial direction of the positioning plate 21. When the locking member 7 is used to lock and fix the positioning rod 22, the installation position of the locking member 7 in the elongated mounting hole can be adjusted, for example, the locking member 7 can be close to one end of the elongated mounting hole along its own length direction, or the locking member 7 can be located in the middle of the elongated mounting hole along its own length direction, so as to adapt to the installation requirements of different models of magnets 1 and positioning plates 21.

[0038] In the above embodiment, at least one end of any positioning rod 22 is provided with a connecting bent rod, the connecting bent rod is L-shaped, and the connecting bent rod is provided with a long strip mounting hole and a locking member 7. Figure 1 The connecting bent rod can clamp the edge of the magnet 1 or the edge of the positioning plate 21 to ensure that the positioning rod 22 is firmly and reliably positioned between the magnet 1 and the positioning plate 21.

[0039] Furthermore, in some embodiments, the magnet 1 is provided with a gradient coil 6 , and the shim bars 3 entering and exiting the magnet 1 are located inside the aforementioned gradient coil 6 .

[0040] In summary, the gradient shimming device provided by the utility model can automatically insert and remove the shim strips 3, can reduce the difficulty of moving the shim strips 3 in a magnetic field environment, can realize multiple shim strips 3 entering and exiting the shim slot 11 at the same time, and is convenient for operators to debug the shim strips 3 that are out of the shim slot 11, such as adding or reducing shim pieces on the shim strips 3. The operator does not need to free up his hands to position the shim strips 3, thereby reducing the operator's workload and improving work efficiency.

[0041] The above is a detailed introduction to the gradient shimming device provided by the present invention. This article uses specific examples to illustrate the principle and implementation method of the present invention. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, the present invention can also be improved and modified, and these improvements and modifications also fall within the scope of protection of the present invention.

Claims

1. A gradient shimming device, characterized in that: The invention comprises a magnet (1), a bracket (2), a plurality of shim bars (3) and a plurality of drivers (4); the magnet (1) is provided with a plurality of shim slots (11) into which all the shim bars (3) can be inserted in a one-to-one correspondence; all the drivers (4) are connected to all the shim bars (3) in a one-to-one correspondence and are used to drive the shim bars (3) to be inserted and removed relative to the shim slots (11); and all the drivers (4) are arranged on the bracket (2).

2. The gradient shimming device according to claim 1, characterized in that: The bracket (2) comprises a positioning plate (21) and a positioning rod (22); the magnet (1) is columnar, the axial end of the magnet (1) and the positioning plate (21) are spaced and parallel, and the two ends of the positioning rod (22) are respectively connected to the magnet (1) and the positioning plate (21); all the drivers (4) are arranged on the positioning plate (21).

3. The gradient shimming device according to claim 2, characterized in that: The bracket (2) further comprises a plurality of guide rods (23); all the guide rods (23) correspond to all the shim strips (3) in a one-to-one manner, the two ends of any guide rod (23) are respectively connected to the magnet (1) and the positioning plate (21), and any shim strip (3) is slidably mounted on the corresponding guide rod (23).

4. The gradient shimming device according to claim 3, characterized in that: Any of the guide rods (23) is provided with a lead screw (51) and a lead screw slider (52) provided on the lead screw (51); any of the shim strips (3) is fitted to the corresponding lead screw (51), and an end of any of the shim strips (3) is connected to the corresponding lead screw slider (52).

5. The gradient shimming device according to claim 4, characterized in that: A plurality of guide rods (23) are provided between the magnet (1) and the positioning disk (21); all of the guide rods (23) are arranged in a ring around the central axis of the positioning disk (21), and all of the shim strips (3) are arranged around the circumference of all of the guide rods (23).

6. The gradient shimming device according to any one of claims 2 to 5, characterized in that: A plurality of positioning rods (22) are provided between the magnet (1) and the positioning plate (21); one end of all the positioning rods (22) is detachably connected to the magnet (1), and the other end of all the positioning rods (22) is detachably connected to the positioning plate (21); at least one end of all the positioning rods (22) is provided with an elongated mounting hole extending radially along the magnet (1) and a locking member (7) provided in the elongated mounting hole.

7. The gradient shimming device according to claim 6, characterized in that: At least one end of any one of the positioning rods (22) is provided with an L-shaped connecting bent rod; the connecting bent rod is provided with the elongated mounting hole and the locking member (7).

8. The gradient shimming device according to any one of claims 1 to 5, characterized in that: The magnet (1) is provided with a gradient coil (6).

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