A water cooling structure for a three-dimensional helmholtz coil

Abstract

This invention relates to the field of water-cooling devices for magnetically controlled coils, and more specifically, to a water-cooling structure for three-dimensional Helmholtz coils. A water-cooling structure for three-dimensional Helmholtz coils includes a coil assembly, an inner cavity support frame, and a water-cooled sealed outer chamber. The inner cavity support frame and the water-cooled sealed outer chamber cooperate to form a sealed cavity. The coil assembly is fixedly sleeved on the outside of the inner cavity support frame and housed within the sealed cavity. The inner cavity support frame and the water-cooled sealed outer chamber together enclose the coil assembly, allowing cooling medium to be introduced into the sealed cavity to completely immerse the coil assembly. The water-cooled sealed outer chamber is provided with an inlet and an outlet connected to the sealed cavity. The cooling medium enters the sealed cavity through the inlet to immerse the coil assembly and then flows out through the outlet to form a circulating cooling loop. Through structural improvements, the cooling medium cools the coil, achieving a stable output of a higher magnetic field strength and enabling continuous operation over long periods.

Description

Technical Field

[0001] This invention relates to the field of water-cooling devices for magnetically controlled coils, and more specifically to a water-cooling structure for three-dimensional Helmholtz coils. Background Technology

[0002] Three-dimensional Helmholtz coils are commonly used magnetic field generators in the field of magnetically controlled microrobots, offering advantages such as high magnetic field uniformity, diverse magnetic field output modes, and a wide operating frequency range. However, as the required magnetic field strength increases, the voltage applied across the coil needs to be increased, leading to increased coil heating power. Under high electrical load operation, the resistance of the copper wire gradually increases with temperature as the operating time increases, ultimately causing a decrease in output magnetic field strength and a deterioration in magnetic field stability. Therefore, it is necessary to design and optimize a water-cooling structure based on the existing three-dimensional Helmholtz coil structure to address these technical shortcomings. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide a water-cooled structure for a three-dimensional Helmholtz coil, which, through structural optimization and improvement, enables the cooling medium to cool the coil, thereby achieving a stable output of a high magnetic field strength and long-term continuous operation.

[0004] The objective of this invention is achieved through the following technical solution:

[0005] A water-cooled structure for a three-dimensional Helmholtz coil includes a coil assembly, an inner cavity support frame, and a water-cooled sealed outer chamber. The inner cavity support frame and the water-cooled sealed outer chamber cooperate to form a sealed cavity. The coil assembly is fixedly sleeved on the outside of the inner cavity support frame and housed within the sealed cavity. The water-cooled sealed outer chamber is provided with an inlet and an outlet connected to the sealed cavity. Cooling medium enters the sealed cavity through the inlet and immerses the coil assembly, then flows out through the outlet to form a circulating cooling loop.

[0006] The coil assembly includes an X-axis coil assembly, a Y-axis coil assembly, and a Z-axis coil assembly; these three coil assemblies are sequentially fitted onto the inner cavity support frame from the inside out. The coil assemblies are made of tightly wound fine copper wire and are used to generate a three-dimensional DC / alternating uniform magnetic field. Both the X-axis and Y-axis coil assemblies contain two pairs of coaxially arranged coils, and the Z-axis coil assembly contains one pair of coaxially arranged coils. The coil assemblies also include four connecting blocks, specifically used to connect the X-axis coil assemblies located on both sides of the origin. Coils on both sides of the same axis are securely connected via these connecting blocks, tightening the entire coil assembly from the outside in. This eliminates the need for independent connecting and fastening devices between individual coils, simplifying the structure and achieving better assembly manufacturability.

[0007] Each coil in the coil assembly is made of copper wire wound around a coil frame. The outer surface of the copper wire is covered with a waterproof, corrosion-resistant, and insulating varnish layer, allowing the copper wire to be in long-term contact with the cooling medium without conducting electricity.

[0008] The inner cavity support frame is a three-dimensional six-way tubular structure, which is not only an important load-bearing component of the overall structure, but also serves as the internal boundary of the sealed space required by the cooling medium, isolating the coil assembly from the outside. Its tube body has a rectangular cross-section and is designed to fit the inner contour of the coil assembly. All six end faces of the inner cavity support frame are provided with flanges for sealing and mating with the water-cooled sealing outer chamber.

[0009] The water-cooled sealed outer chamber includes a water-cooled cylindrical shell, two side shells, six end caps, and a base plate. The water-cooled sealed outer chamber serves as the outer boundary of the sealed cavity, completely enclosing the coil assembly inside, and the overall structure is cylindrical. The water-cooled cylindrical shell is fitted onto the outside of the coil assembly, axially enclosing and limiting the Y-axis and Z-axis coil assemblies. The two side shells are respectively sealed to the two axial ends of the water-cooled cylindrical shell by fasteners. The six end caps are correspondingly and sealed at the six openings of the inner cavity support frame. The end cap structure corresponding to the lower part of the Z-axis is different from the other end cap structures. This bottom end cap is connected to the base plate, relying on the base plate as the support of the overall structure, so that the entire device can be placed stably on the experimental platform.

[0010] Each end cap is provided with a flange around its circumference. The inner side of each end cap is provided with two layers of circumferential sealing grooves, namely a first sealing groove that mates with the flange of the inner cavity support frame, and a second sealing groove that mates with the corresponding plane of the water-cooled cylinder shell or side shell. A sealing ring is installed in the sealing groove. By pressing the end cap with fasteners, the six openings of the inner cavity support frame are simultaneously sealed and connected to the water-cooled cylinder shell and side shell, ensuring the water seal of the sealed cavity.

[0011] The lower part of the water-cooled cylinder shell is symmetrically provided with two waterproof cable interfaces. The waterproof cable interfaces on the water-cooled cylinder shell are used to lead the coil cable to the coil control equipment. The waterproof cable interfaces are equipped with waterproof cable connectors with sealing structures to ensure the water tightness of the wire threading position.

[0012] The inlet and outlet are integrated into a water interface and located at the bottom of the water-cooled shell. The water interface is an integrated inlet and outlet. The water interface is connected to the water chiller through an external water pipe to establish a complete water circulation path. The outlet is connected to a water pipe extending to the upper part of the sealed cavity, so that the cooling medium circulates in the sealed cavity in a bottom-in, top-out flow manner.

[0013] The beneficial effects of this application are:

[0014] 1. This invention employs water-cooling technology. Through the structural design of the internal cavity support frame and the water-cooled outer shell, a sealed cavity environment is created for the coil assembly. Driven by an external water chiller, a continuously updated cooling medium flows through the coil, thereby removing the heat generated by the coil and creating an opportunity to achieve high magnetic field strength in the magnetically controlled coil.

[0015] 2. This invention can complete the water-cooling heat dissipation modification by adding only a few auxiliary components while preserving the original structure of the three-dimensional Helmholtz coil. At the same time, it preserves the original field of view of the device to the maximum extent, and the increase in overall structural weight and external size is controlled within a very small range. Attached Figure Description

[0016] Figure 1 This is an overall schematic diagram of a water-cooling structure for a three-dimensional Helmholtz coil according to the present invention;

[0017] Figure 2 This is a three-dimensional structural diagram of the coil assembly and support frame in the water-cooled structure of the present invention;

[0018] Figure 3 This is an overall front view of the water-cooling structure of the present invention;

[0019] Figure 4 This is a left view of the overall water-cooling structure of the present invention;

[0020] Figure 5 This is a top view of the overall water-cooling structure of the present invention;

[0021] Figure 6 This is a three-dimensional structural schematic diagram and a cross-sectional view of the water-cooled junction end cap of the present invention;

[0022] In the figure: Coil group 1; X-axis coil group 11; Y-axis coil group 12; Z-axis coil group 13; Connecting block 14; Inner cavity support frame 2; Water-cooled sealed outer chamber 3; Water-cooled shell 31; Cable interface 311; Water interface 312; Side shell 32; End cover 33; First sealing groove 331; Second sealing groove 332; Base plate 34. Detailed Implementation

[0023] The following is in conjunction with the appendix Figure 1 To be continued Figure 6 The following provides a more detailed description of the specific embodiments of the present invention. This embodiment is based on the technical solution of the present invention and provides detailed implementation methods and specific assembly and operation processes; however, the scope of protection of the present invention is not limited to the following embodiment.

[0024] like Figure 1As shown in the figure, this embodiment discloses a water-cooled structure for a three-dimensional Helmholtz coil, mainly comprising three parts: a coil assembly 1, an inner cavity support frame 2, and a water-cooled sealed outer chamber 3. The inner cavity support frame 2 and the water-cooled sealed outer chamber 3 are assembled and fitted together to form a closed sealed cavity; the coil assembly 1 is fixedly sleeved on the outside of the inner cavity support frame 2 and is entirely housed inside the sealed cavity; the water-cooled sealed outer chamber 3 is provided with an inlet and an outlet connected to the sealed cavity, and the cooling medium is introduced into the sealed cavity through the inlet and completely submerges the coil assembly 1, and then flows out through the outlet, forming a continuously circulating cooling circuit to remove the heat generated by the coil assembly 1 during operation.

[0025] like Figure 2 As shown, the coil group 1 includes an X-axis coil group 11, a Y-axis coil group 12, a Z-axis coil group 13, and four connecting blocks 14. The X-axis coil group 11 and the Y-axis coil group 12 have large winding radii and low magnetic field strength. To balance the magnetic field strength along the x, y, and z axes, two sets of both the X-axis coil group 11 and the Y-axis coil group 12 are provided. Based on the magnetic field generation characteristics of Helmholtz coils, the larger the coil winding radius, the lower the magnetic field strength in its central region. Therefore, in this embodiment, the Z-axis coil group 13, the Y-axis coil group 12, and the X-axis coil group 11 are sequentially mounted on the inner cavity support frame 2 from the inside out. The X-axis coil group 11 and the Y-axis coil group 12 each contain two pairs of coaxially arranged coils, and the Z-axis coil group 13 contains one pair of coaxially arranged coils. The three sets of coils work together to generate a three-dimensional DC or alternating uniform magnetic field.

[0026] Each axial coil is constructed by tightly winding fine copper wire around a coil frame, with the ends of the copper wire leading out to the outside of the device for connection to external coil control equipment. Each coil frame is equipped with a positioning connection part, and four elongated connecting blocks 14 are arranged circumferentially around the coil group and fixedly connected to the positioning connection part by fastening bolts. The outermost pair of X-axis coil groups 11 are connected as one unit by the four connecting blocks 14. The entire coil group is then clamped from the outside in through the outermost pair of X-axis coil groups 11, eliminating the need for separate connection and fastening devices for each coil, simplifying the overall structure, and improving assembly processability.

[0027] Furthermore, the outer surface of the copper wire is coated with a waterproof, corrosion-resistant, and insulating varnish layer, allowing the copper wire to be in direct contact with the cooling medium for a long period of time without conducting electricity or being corroded, thus ensuring the operational reliability of the coil under immersion cooling conditions.

[0028] like Figure 2As shown, the inner cavity support frame 2 is a three-dimensional six-way tubular structure, which is both the core load-bearing component of the overall water-cooling structure and the internal boundary of the sealed cavity, isolating and supporting the coil group 1 on its outer side. The tube body of the inner cavity support frame 2 has a rectangular cross-section, and the outer wall of the tube is set to fit the inner contour of the coil group 1, making the overall structure compact. Each of the six end faces of the inner cavity support frame 2 is provided with a flange for sealing with the water-cooled sealed outer chamber 3; during assembly, the Z-axis coil group 13, Y-axis coil group 12, and X-axis coil group 11 are sequentially assembled on the outer wall of the inner cavity support frame 2 through transition fit, ensuring the coaxiality and assembly stability of each coil group.

[0029] like Figure 3 , Figure 4 , Figure 5 As shown, the water-cooled sealed outer chamber 3 forms the outer boundary of the sealed cavity, completely enclosing the coil assembly 1 inside, and the overall structure presents a cylindrical shape. The water-cooled sealed outer chamber 3 includes a water-cooled cylindrical shell 31, two side shells 32, six end caps 33, and a bottom plate 34.

[0030] The water-cooled shell 31 is fitted onto the outside of the coil assembly 1, axially enclosing and limiting the Y-axis coil assembly 12 and the Z-axis coil assembly 13. The inner cavity of the water-cooled shell 31 is a square with rounded edges, which matches the outer contour of the coil assembly 1. The outer wall is cylindrical, taking into account both structural adaptability and appearance regularity. The two side shells 32 are respectively sealed to the axial ends of the water-cooled shell 31 by fasteners, sealing the axial opening of the water-cooled shell 31.

[0031] Six end caps 33 are installed at the six openings of the inner cavity support frame 2, respectively. The sealing structure of each end cap 33 is the same, and only the external dimensions are adapted according to the installation position. The bottom end cap 33 located at the lower part of the Z-axis is fixedly connected to the base plate 34, and relies on the base plate 34 as the support base of the overall structure, so that the entire device can be placed stably on the experimental platform.

[0032] like Figure 6 As shown, each end cap 33 has two layers of circumferential sealing grooves on its inner side. These are a first sealing groove 331 that mates with the flange flange of the inner cavity support frame 2, and a second sealing groove 332 that mates with the corresponding plane of the water-cooled cylinder shell 31 or the side shell 32. Both sealing grooves are equipped with sealing rings. When the end cap 33 is tightened by fasteners, the sealing rings are deformed under pressure, which can simultaneously achieve a double seal between the opening of the inner cavity support frame 2 and the outer shell, ensuring the water tightness of the sealed cavity and preventing the leakage of cooling medium.

[0033] Furthermore, the lower part of the water-cooled shell 31 is symmetrically provided with two waterproof cable interfaces 311 for leading out both ends of the copper wires on the coil assembly. Essentially, each interface is an M10×1 threaded hole connected to an M10 waterproof cable connector. The wiring cable of the coil assembly 1 is led out through the waterproof cable interface 311 to the outside of the device and connected to the coil control equipment. The waterproof cable interface 311 is equipped with a waterproof cable connector with a sealing structure. A sealing ring is provided at the threaded part of the connector, and clamping claws and a sealing sleeve are provided at the wire hole to ensure the watertightness of the cable insertion point.

[0034] The inlet and outlet are integrated into a water interface 312 and located at the lower part of the water-cooled shell 31. The water interface 312 can be connected to an external water chiller via an external water pipe to establish a complete water circulation path. The two water interfaces 312 are essentially two G1 / 8 threaded holes, with one inlet for water intake and the other for water outlet. The outlet is connected to a water inlet pipe extending to the upper part of the sealed cavity, allowing the cooling medium to circulate within the sealed cavity in a bottom-in, top-out flow pattern. This effectively removes air from the cavity, ensuring the cooling medium completely submerges the coil assembly 1 and improving cooling heat exchange efficiency.

[0035] In practical use, the water-cooled structure of this embodiment connects the water interface 312 to an external water-cooling circulation system. The cooling medium is introduced into the sealed cavity through the inlet, gradually filling the cavity and completely submerging the coil assembly 1. The heat generated by the coil assembly 1 during energization is directly transferred to the cooling medium through the surface of the copper wire. The heated cooling medium flows out from the top of the cavity through the water inlet and outlet, returning to the water chiller for heat dissipation and cooling, completing the cooling cycle. Under the condition of long-term operation with high electrical load of the coil assembly, the continuously circulating cooling medium can stably remove heat, suppress the rise of coil temperature, and ensure the strength and stability of the magnetic field output.

Claims

1. A water-cooled structure for a three-dimensional Helmholtz coil, comprising a coil assembly (1), an inner cavity support frame (2), and a water-cooled sealed outer chamber (3), characterized in that: The inner cavity support frame (2) cooperates with the water-cooled sealed outer chamber (3) to form a sealed cavity; the coil group (1) is fixedly sleeved on the outside of the inner cavity support frame (2) and housed in the sealed cavity; the water-cooled sealed outer chamber (3) is provided with an inlet and an outlet connected to the sealed cavity, the cooling medium enters the sealed cavity through the inlet and immerses the coil group (1), and then flows out through the outlet to form a circulating cooling circuit.

2. The water-cooling structure for a three-dimensional Helmholtz coil according to claim 1, characterized in that: The coil group (1) includes an X-axis coil group (11), a Y-axis coil group (12) and a Z-axis coil group (13); the Z-axis coil group (13), the Y-axis coil group (12) and the X-axis coil group (11) are sequentially sleeved on the inner cavity support frame (2) from the inside to the outside.

3. A water-cooling structure for a three-dimensional Helmholtz coil according to claim 2, characterized in that: The X-axis coil group (11) and the Y-axis coil group (12) each contain two pairs of coaxially arranged coils, and the Z-axis coil group (13) contains one pair of coaxially arranged coils. The coil group (1) also includes four connecting blocks (14). The outermost pair of X-axis coil groups (11) are connected as one unit through the four connecting blocks (14), and the entire coil group is clamped from the outside to the inside through the outermost pair of X-axis coil groups (11).

4. A water-cooling structure for a three-dimensional Helmholtz coil according to claim 1, characterized in that: Each coil in the coil group (1) is made of copper wire wound around a coil frame. The outer surface of the copper wire is covered with a waterproof and corrosion-resistant insulating varnish layer, so that the copper wire can be in long-term contact with the cooling medium without conducting electricity.

5. A water-cooling structure for a three-dimensional Helmholtz coil according to claim 1, characterized in that: The inner cavity support frame (2) is a three-dimensional six-way tubular structure with a rectangular cross section that fits the inner contour of the coil group (1). All six end faces of the inner cavity support frame (2) are provided with flanges for sealing with the water-cooled sealed outer chamber (3).

6. A water-cooling structure for a three-dimensional Helmholtz coil according to claim 1, characterized in that: The water-cooled sealed outer chamber (3) includes a water-cooled cylindrical shell (31), two side shells (32), six end caps (33), and a bottom plate (34). The water-cooled cylindrical shell (31) is fitted on the outside of the coil assembly (1), and the two side shells (32) are respectively sealed and connected to the two axial ends of the water-cooled cylindrical shell (31). The six end caps (33) are correspondingly sealed and installed at the six openings of the inner cavity support frame (2). The bottom plate (34) is connected below the bottom end caps (33) and is used for supporting the overall structure.

7. A water-cooling structure for a three-dimensional Helmholtz coil according to claim 6, characterized in that: Each end cap (33) has two layers of circumferential sealing grooves on its inner side, namely a first sealing groove (331) that mates with the flange flange of the inner cavity support frame (2) and a second sealing groove (332) that mates with the corresponding plane of the water-cooled cylinder shell (31) or the side shell (32); a sealing ring is installed in the sealing groove, and the water seal of the sealing cavity is achieved by pressing the end cap (33) with fasteners.

8. A water-cooling structure for a three-dimensional Helmholtz coil according to claim 6, characterized in that: The lower part of the water-cooled shell (31) is symmetrically provided with two waterproof cable interfaces (311). The wiring terminals of the coil group (1) are led out to the external control equipment through the waterproof cable interfaces (311). The waterproof cable interfaces (311) are equipped with waterproof cable connectors with sealing structures to ensure the water tightness of the wiring position.

9. A water-cooling structure for a three-dimensional Helmholtz coil according to claim 6, characterized in that: The inlet and outlet are integrated into a water interface (312) and arranged at the lower part of the water-cooled shell (31); the outlet is connected to a water pipe extending to the upper part of the sealed cavity, so that the cooling medium circulates in the sealed cavity in a bottom-in, top-out flow manner.

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