Shielding device for gradient coil

Abstract

The present invention discloses a shielding device for a gradient coil, comprising a steel mesh, the steel mesh being covered with a polyester glass cloth, the polyester glass cloth being embedded on one side of the steel mesh where the steel mesh and the polyester glass cloth are bonded, and both the polyester glass cloth and the steel mesh being impregnated with a resin layer that completely encapsulates the two. Because the polyester glass cloth itself contains polyester fibers and has good fusion with the resin, the steel mesh is pre-impregnated with the resin layer so that the resin layer and the steel mesh completely permeate the steel mesh, thereby firmly encapsulating the steel mesh in the polyester glass cloth and the resin layer. When the shielding device provided by the present invention is then placed in a gradient coil and filled with resin, the outermost resin layer of the shielding device ensures good fusion with the resin poured into the gradient coil, thereby significantly improving product yield. Furthermore, because the steel mesh and the polyester glass cloth are relatively low in price, the shielding device has the advantage of low cost.

Description

Technical Field

[0001] The present invention relates to the technical field of magnetic resonance shielding, and more particularly to a shielding device for a gradient coil. Background Art

[0002] Shielding devices are essential for the gradient coils in magnetic resonance imaging equipment. They need to be integrated into the resin of the gradient coils. There are two common types of shielding devices:

[0003] 1. Use pure stainless steel wire mesh for shielding. Place the stainless steel wire mesh in the gradient coil and infuse it with resin so that the stainless steel wire mesh is integrated into the resin layer. However, the stainless steel wire mesh has high requirements for its subsequent assembly and resin infusion process. In fact, the stainless steel wire mesh is not easy to integrate well with the resin layer, and there is often a problem of separation, resulting in a high product defect rate.

[0004] Second, copper-clad PCBs are used for shielding. The shielding effect is the same as that of stainless steel wire, and it blends well with the resin, with a high product yield. However, the disadvantage is that the PCB itself is relatively expensive, resulting in excessively high costs for the shielding device.

[0005] Therefore, how to solve the problems of high defect rate and high cost of existing shielding device products is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0006] In view of this, an object of the present invention is to provide a shielding device for a gradient coil, which significantly improves the effective integration with the resin layer, improves the product yield, and has the characteristics of low cost.

[0007] In order to achieve the above object, the present invention provides the following technical solutions:

[0008] A shielding device for a gradient coil comprises a steel mesh covered with polyester glass fiber cloth, wherein the side of the steel mesh where the steel mesh and the polyester glass fiber cloth are bonded is embedded in the polyester glass fiber cloth, and the polyester glass fiber cloth and the steel mesh are both soaked in a resin layer that completely wraps the two.

[0009] Preferably, the steel mesh is a stainless steel mesh.

[0010] Preferably, the resin layer has a uniform thickness.

[0011] Preferably, the steel wire mesh and the polyester glass fiber cloth are hot-pressed.

[0012] Preferably, the polyester glass fiber cloth includes a first polyester glass fiber cloth and a second polyester glass fiber cloth respectively covering the front and back of the steel mesh, the front of the steel mesh is embedded in the first polyester glass fiber cloth, and the back of the steel mesh is embedded in the second polyester glass fiber cloth.

[0013] Preferably, the length of the resin layer is 1400 mm.

[0014] The shielding device for the gradient coil provided by the present invention has a steel mesh embedded in a polyester glass fiber cloth so that the steel mesh and the polyester glass fiber cloth form an integral whole. At the same time, the steel mesh and the polyester glass fiber cloth are soaked in a resin layer that completely wraps the two. Since the polyester glass fiber cloth itself contains polyester fibers, the polyester glass fiber cloth and the resin have good fusion properties. Before the resin is poured into the gradient coil, the resin layer is pre-soaked in the steel mesh so that the resin layer completely penetrates the gaps in the steel mesh, thereby firmly wrapping the steel mesh in the polyester glass fiber cloth and the resin layer. When the shielding device provided by the present invention is placed in the gradient coil and the resin is poured, since the outermost layer of the shielding device is the resin layer, it can be ensured that the shielding device and the resin poured into the gradient coil are well fused, thereby significantly improving the product yield. At the same time, since the steel mesh and the polyester glass fiber cloth are relatively low in price, they have the advantage of low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0016] Figure 1 A schematic diagram of the internal structure of a specific embodiment of a shielding device for a gradient coil provided by the present invention;

[0017] Figure 2 for Figure 1 A partial enlarged view of part A.

[0018] Among them, 1-steel wire mesh, 2-resin layer, 3-polyester glass fiber cloth, 31-first polyester glass fiber cloth, 32-second polyester glass fiber cloth. DETAILED DESCRIPTION

[0019] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0020] The core of the present invention is to provide a shielding device for a gradient coil, which significantly improves the effective integration with the resin layer, improves the product yield, and has the characteristics of low cost.

[0021] Please refer to Figures 1 to 2 , Figure 1 A schematic diagram of the internal structure of a specific embodiment of a shielding device for a gradient coil provided by the present invention; Figure 2 for Figure 1 A partial enlarged view of part A.

[0022] The shielding device for the gradient coil provided by the present invention includes a steel mesh 1, which is covered with a polyester glass fiber cloth 3. The polyester glass fiber cloth 3 is embedded in the side where the steel mesh 1 and the polyester glass fiber cloth 3 are bonded. The polyester glass fiber cloth 3 and the steel mesh 1 are both impregnated with a resin layer 2 that completely wraps the two.

[0023] Among them, the polyester glass fiber cloth 3 is a composite geosynthetic material composed of 60% glass fiber and 40% polyester fiber. Since the polyester glass fiber cloth 3 itself contains polyester fiber, the polyester glass fiber cloth 3 has good fusion with the resin. The polyester glass fiber cloth 3 has a certain thickness. Therefore, the polyester glass fiber cloth 3 can be covered on the steel mesh 1, and the side of the steel mesh 1 where the polyester glass fiber cloth 3 is in contact with the polyester glass fiber cloth 3 is embedded in the polyester glass fiber cloth 3. The polyester glass fiber cloth 3 and the steel mesh 1 are also impregnated with a resin layer 2 that completely wraps the two. As a result, the outer layer of the shielding device provided by the present invention is the resin layer 2, which can be reliably integrated with the resin in the gradient coil.

[0024] Specifically, the steel mesh 1 and the polyester glass fiber cloth 3 can be stacked in a mold, and liquid resin is poured into the mold so that the resin penetrates into the gaps of the steel mesh 1 and completely wraps the steel mesh 1 and the polyester glass fiber cloth 3. Then, one side of the steel mesh 1 is pressed into the polyester glass fiber cloth 3 by hot pressing, so that one side of the steel mesh 1 is embedded in the polyester glass fiber cloth 3. After the resin solidifies, a resin layer 2 is formed that penetrates the gaps of the steel mesh 1 and completely wraps the steel mesh 1 and the polyester glass fiber cloth 3. The side of the steel mesh 1 that contacts the polyester glass fiber cloth 3 is embedded in the polyester glass fiber cloth 3, so that the polyester glass fiber cloth 3 and the resin layer 2 firmly wrap the steel mesh to prevent the steel mesh 1 from falling off.

[0025] Therefore, in the shielding device for the gradient coil provided by the present invention, the steel mesh 1 is embedded in the polyester glass fiber cloth 3 so that the steel mesh 1 and the polyester glass fiber cloth 3 form a whole, and at the same time, the resin layer 2 that completely wraps the steel mesh 1 and the polyester glass fiber cloth 3 is soaked in the resin layer 2. Since the polyester glass fiber cloth 3 itself has polyester fibers, the polyester glass fiber cloth 3 has good fusion with the resin. Before the resin is poured into the gradient coil, the resin layer 2 is soaked in the steel mesh 1 in advance so that the resin layer 2 completely penetrates the gaps in the steel mesh 1, thereby firmly wrapping the steel mesh 1 in the polyester glass fiber cloth 3 and the resin layer 2. When the shielding device provided by the present invention is placed in the gradient coil and the resin is poured, since the outermost layer of the shielding device is the resin layer 2, it can be ensured that the shielding device and the resin poured into the gradient coil are well fused, thereby significantly improving the product yield. At the same time, since the steel mesh 1 and the polyester glass fiber cloth 3 are relatively low in price, they have the advantage of low cost.

[0026] Based on the above embodiment, preferably, the steel mesh 1 is a stainless steel mesh, which can prevent the steel mesh 1 from rusting and ensure the firmness of the steel mesh 1 embedded in the polyester glass fiber cloth 3.

[0027] Based on the above embodiment, the resin layer 2 preferably has a uniform thickness. Considering the specific method of impregnating the stainless steel mesh with the resin layer 2, the stainless steel mesh and the polyester glass fiber cloth 3 can be stacked and placed in a mold for impregnation with the resin. Liquid resin is then poured into the mold. After the resin solidifies, a shielding device with a uniform thickness is formed. Furthermore, the depth of the mold can be used to control the overall thickness of the shielding device.

[0028] Based on the above embodiment, considering the specific method of embedding the steel mesh 1 into the polyester glass fiber cloth 3, it is preferred that the steel mesh 1 and the glass fiber cloth are hot-pressed. That is, after the stainless steel mesh and the polyester glass fiber cloth 3 are stacked in a mold and poured with resin, the stainless steel mesh is pressed into the polyester glass fiber cloth 3 by a hot-pressing machine, so that one side of the steel mesh 1 is pressed into the polyester glass fiber cloth 3, thereby embedding one side of the steel mesh 1 in the polyester glass fiber cloth 3.

[0029] Based on any of the above embodiments, preferably, the polyester glass fiber cloth 3 includes a first polyester glass fiber cloth 31 and a second polyester glass fiber cloth 32 respectively covering the front and back of the steel wire mesh 1, the front of the steel wire mesh 1 is embedded in the first polyester glass fiber cloth 31, and the back of the steel wire mesh 1 is embedded in the second polyester glass fiber cloth 32.

[0030] In this embodiment, to further improve the reliability of the fusion between the steel mesh 1 and the resin layer 2, preferably, the front and back sides of the steel mesh 1 are covered with polyester fiberglass cloth 3, with the front side of the steel mesh 1 embedded with a first polyester fiberglass cloth 31 and the back side of the steel mesh 1 embedded with a second polyester fiberglass cloth 32. Thus, when the steel mesh 1, the first polyester fiberglass cloth 31, and the second polyester fiberglass cloth 32 are immersed in resin, the resin impregnated in the gaps of the steel mesh 1 can fuse with the first polyester fiberglass cloth 31 and the second polyester fiberglass cloth 32, respectively, and firmly adhere together, thereby firmly wrapping the steel mesh 1 in the first polyester fiberglass cloth 31, the second polyester fiberglass cloth 32, and the resin layer 2, further improving the reliability of the shielding device provided by the present invention. Of course, a layer of polyester fiberglass cloth 3 can also be provided on only one side of the steel mesh 1, and the specific arrangement can be flexibly based on needs.

[0031] Based on the above embodiment, considering the specific dimensions of the resin, and because the resin thickness is determined based on the diameter of the gradient coil, the preferred length of the resin layer 2 is 1400 mm. Furthermore, the number of layers of polyester fiberglass cloth 3 can be increased or decreased depending on the size of the gradient coil.

[0032] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0033] The shielding device for a gradient coil provided by the present invention has been described in detail above. Specific examples have been used herein to illustrate the principles and implementation methods of the present invention. The description of the above examples is intended only to facilitate understanding of the method and core concepts of the present invention. It should be noted that those skilled in the art will be able to make various improvements and modifications to the present invention without departing from the principles of the present invention, and such improvements and modifications are also within the scope of protection of the claims of the present invention.

Claims

1. A shielding device for a gradient coil, characterized in that: The invention comprises a steel mesh (1), the steel mesh (1) is covered with a polyester glass fiber cloth (3), the side of the steel mesh (1) where the polyester glass fiber cloth (3) is bonded is embedded in the polyester glass fiber cloth (3), and both the polyester glass fiber cloth (3) and the steel mesh (1) are impregnated with a resin layer (2) that completely wraps the two. The polyester glass fiber cloth (3) comprises a first polyester glass fiber cloth (31) and a second polyester glass fiber cloth (32) respectively covering the front and back sides of the steel mesh (1); the front side of the steel mesh (1) is embedded in the first polyester glass fiber cloth (31), and the back side of the steel mesh (1) is embedded in the second polyester glass fiber cloth (32); The steel wire mesh (1) and the polyester glass fiber cloth (3) are hot-pressed into shape.

2. The shielding device for a gradient coil according to claim 1, characterized in that: The steel wire mesh (1) is a stainless steel wire mesh.

3. The shielding device for a gradient coil according to claim 2, characterized in that: The thickness of the resin layer (2) is uniform.

4. The shielding device for a gradient coil according to any one of claims 1 to 3, characterized in that: The length of the resin layer (2) is 1400 mm.

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