Welding positioning device, welding method, and brain electrode device

Abstract

The application discloses a welding positioning device, a welding method and a brain electrode device, and relates to the technical field of brain-computer interfaces. The welding positioning device comprises a first positioning assembly and a second positioning assembly. The first positioning assembly is provided with a first positioning structure. The first positioning structure comprises a positioning groove for embedding a circuit board. The second positioning structure comprises a positioning plate, a contour marking area and a through hole array. When the second positioning assembly is located at a first position, the surface of the positioning plate close to the side of the first positioning assembly is a first surface. The contour marking area is arranged on the first surface and is used for accommodating a flexible electrode. The contour marking area comprises a through hole array corresponding to a welding hole. The through hole array corresponds to penetrating through the positioning plate. The through hole array comprises a plurality of first through holes. The first through holes are communicated with the positioning groove. The positioning plate is a plurality of positioning plates. By replacing the positioning plate located at the first position, the aperture of the first through hole is adjusted, and the amount of conductive fluid slurry is controlled.

Description

[0001] This application is a divisional application. The original application has the application number 202511385029.0 and the original application date is September 26, 2025. The entire contents of the original application are incorporated herein by reference. Technical Field

[0002] This application relates to the field of brain-computer interface technology, and in particular to a welding positioning device, welding method and brain electrode device. Background Technology

[0003] Brain-computer interfaces (BCIs) are communication and control channels established between the brain and computers or other external devices. Through these channels, users can directly express their thoughts or manipulate devices using their brains. BCIs not only enable the brain to output information to external devices, but also to input information into the brain through stimuli such as electricity, magnetism, light, and sound. Therefore, BCIs establish a direct channel for information exchange between the biological brain and intelligent machines. They can interpret brain signals, control external devices, and encode information to input into the brain, thereby replacing, repairing, enhancing, or improving brain function to achieve bidirectional interaction, collaborative work, and functional integration between the brain and intelligent machines.

[0004] Brain-computer interface (BCI) devices are devices that directly contact brain tissue to acquire electroencephalogram (EEG) signals or directly stimulate the brain, enabling information input / output. A BCI device consists of flexible electrodes and a circuit board. Ensuring a reliable connection between the flexible electrodes and the circuit board is a key technological step in stably achieving the desired functions.

[0005] Circuit boards mainly include rigid circuit boards and flexible circuit boards. Rigid circuit boards include ceramic printed circuits (CPCBs), while flexible circuit boards include flexible printed circuits (FPCs).

[0006] Currently, the mainstream welding technologies are mainly divided into two categories: gold wire welding and anisotropic conductive film (ACF film) welding. Both of these commonly used welding technologies share some common drawbacks. In the welding and production of brain electrode devices, the process typically relies heavily on manual experience to align the flexible electrodes with the pads on the circuit board, making precise positioning between the flexible electrodes and the circuit board difficult and resulting in low welding efficiency.

[0007] Therefore, there is an urgent need to propose a technology that does not rely on human experience for positioning and can improve welding efficiency to solve the technical problems existing in the current technology. Summary of the Invention

[0008] A welding positioning device, a welding method, and a brain electrode device are provided to solve the above-mentioned technical problems.

[0009] In a first aspect, a welding positioning device is provided to assist in the connection and positioning of a brain electrode device, the brain electrode device comprising flexible electrodes, a circuit board, and conductive connectors. The welding positioning device includes: A first positioning component, the first positioning component being provided with a first positioning structure, the first positioning structure including a positioning groove for fitting a circuit board; The second positioning component has a second positioning structure that can restrict the flexible electrode to a side surface facing the first positioning component. The second positioning component has a first position that is aligned and attached to the first positioning component and a second position that is separated from the first positioning component. The flexible electrode is provided with a first pad, and the first pad is provided with a solder hole. The circuit board is provided with a second pad. The cured conductive fluid slurry can form the conductive connector that connects the first pad and the second pad. The second positioning structure includes a positioning plate, a contour marking area, and a through-hole array. The surface of the positioning plate near the first positioning component is a first surface. The contour marking area is disposed on the first surface and is used to accommodate the flexible electrode. The contour marking area includes a through-hole array corresponding to the solder hole. The through-hole array penetrates the positioning plate and includes a plurality of first through holes. The first through holes communicate with the positioning groove so that conductive fluid slurry is injected into the surface of the second solder pad along the first through holes. The positioning plates are multiple, and each of the multiple positioning plates is provided with an array of through holes of different array specifications. The diameter of the first through hole in the array of through holes of different array specifications is different, so as to adjust the diameter of the first through hole by replacing the positioning plate located at the first position, thereby controlling the amount of conductive fluid slurry.

[0010] Optionally, the second positioning component further includes a clamping component, which includes a first frame and a second frame. Along a first direction, the first frame is located on opposite sides of the positioning plate and has a clamping state for fixing the positioning plate and a loosening state for removing the positioning plate. When the clamping component is in the clamping state, the positioning plate is clamped and embedded between the first frame and the second frame.

[0011] Optionally, when the clamping component is in the clamping state, the geometric center of the through-hole array coincides with the geometric center of the first frame and the second frame.

[0012] Optionally, the first frame is provided with a first clearance hole, and the through hole array is located within the space formed by the inner wall of the first clearance hole and the positioning plate.

[0013] Optionally, the first positioning component is provided with a first limiting structure, and the second positioning component is provided with a second limiting structure. When the second positioning component is located at the first position, the first limiting structure and the second limiting structure cooperate to prevent the second positioning component from shifting relative to the first positioning component.

[0014] Optionally, the first limiting structure includes a punch, which protrudes from the surface of the first positioning component near the second positioning component, and the positioning groove is disposed on the punch. The second limiting structure includes a limiting groove, which is disposed on the side of the second positioning component near the first positioning component. The limiting groove is adapted to the punch. When the second positioning component is located in the first position, the limiting groove is sleeved on the punch and fits against the surface of the punch.

[0015] Optionally, the first positioning component further includes a base, the punch is detachably protruding from the surface of the base near the second positioning component, and the positioning groove is disposed on the punch.

[0016] Optionally, the second positioning component further includes a clamping component, which can be configured with the positioning plate to form the limiting groove. The limiting groove is adapted to the punch and can be sleeved on the punch and fit against the surface of the punch.

[0017] Optionally, the conductive connector is at least partially embedded in the solder hole, and the first solder pad and the solder hole have an asymmetrical elliptical structure.

[0018] Secondly, a welding method is provided, the welding method being implemented by the aforementioned welding positioning device, the welding method comprising: The circuit board is secured to the first positioning component via a positioning slot; The second positioning component without the flexible electrode is moved to the first position, and the conductive fluid slurry is injected into the surface of the second pad along the through-hole array. At this time, the through-hole array is a first specification array, and the orthographic projection of the first through-hole in the through-hole array has a first area. After the conductive fluid slurry is injected through the first through hole of the through hole array, the positioning plate is replaced. At this time, the through hole array of the positioning plate is a second specification array, and the orthographic projection of the first through hole of the through hole array has a second area. The flexible electrode is adsorbed and fixed to the contour marking area; After the second positioning component carrying the flexible electrode is moved to the first position, pressure is applied to the flexible electrode toward the circuit board, forcing the conductive fluid slurry to fill from the surface of the second pad along the corresponding solder hole to the surface of the first pad, or to extend from the surface of the second pad to the surface of the first pad and fill to the opposite side of the solder hole under the pressure; the conductive fluid slurry is heated and cured to form the conductive connector metallurgically bonded to the first pad and the second pad.

[0019] Optionally, the first area is smaller than the projected area of ​​the second pad.

[0020] Optionally, the second area is equal to the projected area of ​​the second pad.

[0021] Optionally, after the conductive fluid slurry is heated and cured to form a metallurgical bond between the conductive connector and the first and second pads, the welding method may further include... Replace the positioning plate. At this time, the through-hole array of the positioning plate is a third specification array. At this time, the orthographic projection of the first through-hole in the through-hole array has a third area. The third area is less than or equal to the orthographic projection area of ​​the second pad, and is greater than the first area and less than the second area. Then, the second positioning component without the flexible electrode is moved to the first position, so that the conductive fluid slurry is injected into the surface of the second pad along the first through hole and covers the surface of the first pad or the opposite side of the solder hole. After the conductive fluid slurry fills the gap between the first pad, the second pad and the conductive connector, it is heated again until the conductive fluid slurry solidifies.

[0022] Optionally, the step of adsorbing and fixing the flexible electrode to the contour marking area includes: A volatile adsorbent is sprayed onto the outline marking area, and the flexible electrode is adsorbed and fixed onto the outline marking area, so that the edge contour of the flexible electrode coincides with the contour line of the outline marking area.

[0023] Optionally, the welding method further includes: The conductive fluid slurry is injected into the surface of the positioning plate away from the first positioning component, and the conductive fluid slurry is scraped across the via array at a predetermined speed so that the conductive fluid slurry is injected along the via array to the surface of the second pad; and / or, The step of applying pressure toward the circuit board to the flexible electrode includes, The pressure block is placed on the surface of the positioning plate away from the first positioning component, and the orthographic projection of the flexible electrode along the first direction is located within the orthographic projection of the pressure block along the first direction. Pressure is applied to the flexible electrode by pressing the pressure block.

[0024] Thirdly, a brain electrode device is provided, which is obtained by welding using the aforementioned welding method through a welding positioning device with the aforementioned structure.

[0025] This application provides a welding positioning device, a welding method, and a brain electrode device. The brain electrode device includes a circuit board and flexible electrodes. The welding positioning device includes a first positioning component and a second positioning component. A first positioning structure on the first positioning component can constrain the circuit board within the first positioning component, and a second positioning structure on the second positioning component can constrain the flexible electrodes within the second positioning component. Different arrays of through holes with different array specifications are provided on different positioning plates, and the diameter of the first through hole in the different array specifications is different. By adjusting the diameter of the first through hole, the amount of conductive fluid slurry can be effectively controlled. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings, wherein the same reference numerals in the following description denote the same parts.

[0028] Figure 1 This is a schematic diagram of the overall structure of the brain electrode device in some embodiments.

[0029] Figure 2 This is a schematic diagram of the overall structure of the brain electrode device, including a rigid circuit board, in some embodiments.

[0030] Figure 3 This is a schematic diagram of the overall structure of the brain electrode device, including a flexible circuit board, in some embodiments.

[0031] Figure 4 This is a schematic diagram of the specific structure of the first pad of the flexible electrode of the brain electrode device in some embodiments.

[0032] Figure 5 This is a schematic diagram of the overall structure of the welding positioning device in some embodiments.

[0033] Figure 6This is a schematic diagram of the specific structure of the first positioning component in some embodiments.

[0034] Figure 7 This is a schematic diagram of the specific structure of the second positioning component in some embodiments.

[0035] Figure 8 This is a bottom view of the second positioning component in some embodiments.

[0036] Figure 9 This is a schematic diagram of the overall structure of the welding positioning device in some other embodiments.

[0037] Figure 10 This is a schematic diagram of the overall structure of the welding positioning device at different angles in some other embodiments.

[0038] Figure 11 This is a schematic diagram of the specific structure of the first positioning component in some other embodiments.

[0039] Figure 12 This is a schematic diagram of the specific structure of the second positioning component in some other embodiments.

[0040] Figure 13 This is a schematic flowchart of a welding method provided in some embodiments of this application; Figure 14 This is a schematic flowchart of a welding method provided in some other embodiments of this application.

[0041] The above figures include the following reference numerals: 10. Flexible electrode; 11. First pad; 110. Solder hole; 12. First side; 13. Second side; 14. Contact area; 20. Circuit board; 21. Second solder pad; 30. Conductive connector; 31. First conductive layer; 32. Second conductive layer; 40. First positioning component; 401. First positioning structure; 402. First groove; 41. Base; 42. Punch; 421. Positioning slot; 43. Fastening component; 431. Fixing hole; 44. Second guide component; 441. Second protrusion; 442. Guide hole; 50. Second positioning component; 501. Second positioning structure; 011. Contour marking area; 1a. Main body area; 1b. Extension area; 502. Through hole array; 021. First through hole; 503. First surface; 51. Clamping component; 511. First frame; 5111. First clearance hole; 512. Second frame; 5121. Second clearance hole; 52. Positioning plate; 531. Locking component; 532. Connecting hole; 54. Limiting groove; 60. Receiving cavity; 61. Second groove; 62. Third groove; 70. First guide component; 71. First protrusion; 72. Second through hole. Detailed Implementation

[0042] 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 a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the protection scope of this application.

[0043] In the embodiments of this application, "at least one" refers to one or more; "multiple" refers to two or more. In the description of this application, the terms "first," "second," "third," etc., are used only for the purpose of distinguishing descriptions and should not be construed as indicating or implying relative importance, nor should they be construed as indicating or implying order.

[0044] References such as "one embodiment" or "some embodiments" as used in this specification mean that one or more embodiments of this application include specific features, structures, or characteristics described in connection with that embodiment. Different components and techniques in different embodiments can be freely combined with each other. The terms "comprising," "including," "having," and variations thereof in this specification mean "including but not limited to," unless otherwise specifically emphasized.

[0045] It should be noted that in the embodiments of this application, "and / or" describes the relationship between associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. In addition, the character " / ", unless otherwise specified, generally indicates that the associated objects before and after it are in an "or" relationship.

[0046] It should be noted that in the embodiments of this application, "connection" can be understood as electrical connection. The connection between two electrical components can be a direct or indirect connection between the two electrical components. For example, the connection between A and B can be a direct connection between A and B, or an indirect connection between A and B through one or more other electrical components.

[0047] Definition: The vertical direction Z is the first direction, the horizontal direction X is the second direction, and the horizontal direction Y is the third direction.

[0048] Combination Figures 1 to 3 As shown, this application provides a brain electrode device, which includes a flexible electrode 10, a circuit board 20, and a conductive connector 30.

[0049] The flexible electrode 10 has a welding area. Along the thickness direction of the flexible electrode 10, the welding area is located on one side of the opposite sides of the flexible electrode 10, and the welding area is provided with a plurality of first welding pads 11.

[0050] Optionally, the flexible electrode 10 is typically an elongated sheet-like thin film, including a supporting substrate layer and a metal wire layer bonded and distributed on the substrate layer. Specifically, the substrate layer material is typically polyimide, and the metal wire layer material is typically gold. The thickness of the flexible electrode 10 is 5 μm to 100 μm.

[0051] Optionally, the flexible electrode 10 further includes a contact region 14 for contacting brain tissue. The contact region 14 is spaced apart from the welding region along its length.

[0052] Optionally, along the thickness direction of the flexible electrode 10, the flexible electrode 10 includes a first side 12 and a second side 13.

[0053] Optionally, multiple first pads 11 are arranged in an array.

[0054] The circuit board 20 is provided with a plurality of second pads 21, and the plurality of second pads 21 are provided in a one-to-one correspondence with the plurality of first pads 11.

[0055] Optionally, the circuit board 20 includes a rigid circuit board, such as a ceramic substrate, a metal substrate, an epoxy fiberglass cloth substrate, a glass substrate, etc., preferably a ceramic substrate.

[0056] Optionally, the circuit board 20 includes a flexible circuit board, such as a polyimide substrate, a liquid crystal polymer substrate, a poly(p-dimethyl ethylene glycol) substrate, a polypropylene substrate, etc., preferably a polyimide substrate.

[0057] The conductive connector 30 includes multiple conductive connectors 30, which are connected one-to-one between multiple first pads 11 and multiple second pads 21.

[0058] Optionally, the conductive connector 30 is a structure formed by the curing of conductive fluid slurry injected between the first pad 11 and the second pad 21, and there is a gap between two adjacent conductive connectors 30.

[0059] Alternatively, the conductive fluid paste can be one or more of the following: carbon black paste, graphite paste, conductive gold paste, conductive platinum paste, conductive silver paste, conductive copper paste, conductive carbon paste, graphene paste, conductive solder paste, and composite paste.

[0060] It is important to emphasize that the flexible electrode 10 and the circuit board 20 of the brain electrode device can be precisely positioned through the aforementioned conductive connector 30. Furthermore, the conductive connector, which is formed by the solidification of conductive fluid slurry, makes it less likely for two adjacent first pads 11 and two adjacent second pads 21 to short-circuit.

[0061] In some embodiments, each of the first pads 11 is provided with a solder hole 110, and the conductive connector 30 is at least partially embedded in the solder hole 110.

[0062] Understandably, the solder hole 110 can not only serve as a channel for the conductive fluid slurry to flow to the surface of the first solder pad 11 and the surface of the second solder pad 21, but also improve the stability and connection strength of the conductive connector 30 between the first solder pad 11 and the second solder pad 21.

[0063] In some embodiments, the first pad 11 and the solder hole 110 are asymmetrical elliptical structures.

[0064] Optionally, combined Figure 4 As shown, the first pad 11 and the solder hole 110 of the flexible electrode 10 are both elliptical structures. The elliptical first pad 11 is located on the outer ring, and the other elliptical solder hole 110 is located inside the first pad 11. The two are asymmetrical elliptical structures. Furthermore, the two are asymmetrical elliptical structures with inner and outer rings on the same plane.

[0065] It should be noted that, in the process of using conductive fluid paste for soldering, compared to the radially symmetrical structure of circular pads and solder holes, the use of an asymmetrical elliptical structure with inner and outer rings, especially the elliptical solder hole 110, can form a directional guiding channel for the conductive fluid paste by utilizing the extension characteristics of the long axis of the elliptical structure. The long axis of the elliptical solder hole can reduce the resistance of the conductive fluid paste (reducing the flow shear force by about 30%-40%), promoting the uniform spread of the conductive fluid paste along the long axis, avoiding local accumulation or voids, and thus significantly increasing the effective contact area between the conductive fluid paste and the pad (25%-35% higher than that of circular pads).

[0066] Specifically, in combination Figure 4 As shown, in some embodiments, the ratio between the major axis and the minor axis of the first pad 11 is 2:1. For example, the length of the major axis of the elliptical structure of the first pad 11 is specifically set to 100μm-400μm, and the width of the minor axis is 50μm-200μm.

[0067] Specifically, in combination Figure 4As shown, in some embodiments, the ratio between the major axis and the minor axis of the weld hole is 5:2. For example, the length of the major axis of the weld hole in the elliptical structure is specifically set to 50μm-250μm, and the width of the minor axis is 20μm-100μm.

[0068] It is particularly important to emphasize that when the first pad 11 is set to an elliptical structure, it can also be highly matched with the deformation direction of the ball diameter in gold wire welding and the pressure distribution of ACF film welding. For example, during gold wire welding, the major axis of the elliptical first pad 11 can accommodate the major axis direction of the ball weld deformation, preventing the ball weld from overflowing the edge of the first pad. During ACF film welding and pressing, the narrow design of the minor axis of the elliptical first pad 11 can concentrate the pressure stress and increase the contact probability between the conductive particles and the first pad (approximately 20% higher than that of a circular pad). In other words, the elliptical pad structure can better adapt to various mainstream welding processes and achieve better welding results.

[0069] It should be noted that the first pad 11, the solder hole 110 and the second pad 21 can all be set as elliptical structures or as annular elliptical structures with internal and external symmetry. No specific restrictions are made here. The corresponding structures have the same effect as the aforementioned structures and will not be described again here.

[0070] In some embodiments, a plurality of first pads 11 and contact areas 14 are located on the same side of the flexible electrode 10, the plurality of first pads 11 are used to connect correspondingly to the second pads 21 of the circuit board 20, and the contact areas 14 are used to directly contact brain tissue.

[0071] Optionally, the plurality of first pads 11 and contact areas 14 are all located on the first side 12 or the second side 13 of the flexible electrode 10. Preferably, combined with Figure 2 As shown, multiple first pads 11 and contact areas 14 are located on the first side 12 of the flexible electrode 10. The solder holes 110 provided in the first pads 11 extend from the first side 12 to the corresponding second side 13. The contacts of the contact areas 14 are arranged in a direction away from the second side 13.

[0072] The circuit board 20 includes a rigid circuit board or a flexible circuit board. Preferably, it is combined with... Figure 2 As shown, the circuit board 20 includes a rigid circuit board, such as a ceramic substrate. A plurality of second pads 21 are provided on the side of the rigid circuit board facing the flexible electrode 10, and the plurality of second pads 21 correspond one-to-one with the plurality of first pads 11.

[0073] Optionally, the conductive connector 30 includes a first conductive layer 31 and a second conductive layer 32. The first conductive layer 31 is located between the first pad 11 of the flexible electrode 10 and the second pad 21 of the circuit board 20 and extends at least partially from the second pad 21 along the solder hole 110 to contact the surface of the first pad 11. The second conductive layer 32 at least partially covers the first conductive layer 31 and extends to the surface of the first pad 11, and is connected to the first conductive layer 31.

[0074] Specifically, the first conductive layer 31 and the second conductive layer 32 are designed to improve the welding reliability and connection strength between the first pad 11 of the flexible electrode 10 and the second pad 21 of the circuit board 20. These are formed by repeating the same welding process, i.e., screen printing the conductive fluid paste at least twice, and then curing the resulting structure. Specifically, the first conductive layer 31 is the paste coating structure formed by the first screen printing and curing of the conductive fluid paste. The second conductive layer 32 is the paste coating structure formed by repeating the second screen printing and curing of the conductive fluid paste based on the formation of the first conductive layer 31. Figure 2 and Figure 3 As shown, the welding structure of this "sandwich-like" conductive path ensures the mechanical bonding strength of the welding interface of the brain electrode device, and the contour consistency and thickness uniformity of each conductive layer are highly controllable, which facilitates mass production with a high yield rate.

[0075] It is particularly important to emphasize that when the first pad 11 is disposed on the first side 12 of the flexible electrode 10, at least two screen printings of conductive fluid paste must be performed between the first pad 11 and the second pad 21 of the circuit board 20, and the two curings will form the first conductive layer 31 and the second conductive layer 32 respectively to form a conductive connector 30, thereby ensuring that the first pad 11 and the second pad 21 are reliably soldered together.

[0076] In other embodiments, a plurality of first pads 11 are located on the second side 13. Solder holes 110 provided in the first pads 11 extend from the second side 13 to the corresponding first side 12.

[0077] Optionally, the contact area 14 may be disposed on the first side 12 or the second side 13 of the flexible electrode 10, preferably in combination with Figure 3 As shown, the contact area 14 is located on the first side 12. Further, the contacts of the contact area 14 can be positioned towards the second side 13, or they can be positioned away from the second side 13. Preferably, the contacts of the contact area 14 are positioned away from the second side 13.

[0078] The circuit board 20 includes a rigid circuit board or a flexible circuit board. Preferably, such as... Figure 3As shown, the circuit board 20 includes a flexible circuit board, such as a polyimide substrate. A plurality of second pads 21 are provided on the side of the flexible circuit board facing the flexible electrode 10, and the plurality of second pads 21 correspond one-to-one with the plurality of first pads 11.

[0079] Optionally, the first pad 11 and the second pad 21 abut against each other, and the conductive connector 30 extends from the surface of the second pad 21 to the first side 12 corresponding to the solder hole 110.

[0080] It should be noted that when the first pad 11 and the second pad 21 are in contact, only one screen printing of the conductive fluid paste is required, and the conductive connector 30 is formed in one step, thus reliably welding the first pad 11 and the second pad 21 together. Depending on actual needs, the screen printing and welding process of the conductive fluid paste can be repeated.

[0081] In some embodiments, combined with Figure 2 and Figure 3 As shown, the brain electrode device also includes a protective reinforcement layer, which is at least partially embedded in the pore between the weld hole 110 and the conductive connector 30.

[0082] Specifically, the protective reinforcement layer can be formed by curing a protective reinforcement fluid, which may include one or more of the following: epoxy resin silicone, organic silicone, polyurethane, acrylate, and UV adhesive (ultraviolet light curing adhesive). For example, if the protective reinforcement fluid is composed of epoxy resin silicone, after the flexible electrode 10 and circuit board 20 in the brain electrode device are welded together via conductive connectors 30, the epoxy resin silicone, being in a fluid state, is injected along the weld holes 110 of the flexible electrode 10. At this time, although the weld holes 110 are filled with conductive connectors 30 formed by curing the conductive fluid slurry, the conductive connectors 30 and the weld holes 110 are not tightly bonded without gaps. The epoxy resin silicone fluid will completely fill these gaps along the guide of the conductive connectors 30. It should be noted that the formation of other protective reinforcement fluids with different compositions is similar, and will not be elaborated further here.

[0083] Furthermore, a protective reinforcing fluid can be applied to the entire first side 12 of the flexible electrode 10, forming a protective reinforcing layer integrally. This not only further improves the welding strength between the flexible electrode 10 and the circuit board 20, but also protects the flexible electrode 10 from oxidation.

[0084] In some embodiments, combined with Figures 5-12As shown, the present invention provides a welding positioning device for assisting in the connection and positioning between the circuit board and the flexible electrode 10 in the aforementioned brain electrode device. The welding positioning device includes a first positioning component 40 and a second positioning component 50. The first positioning component 40 is mainly used for the precise positioning and fixing of the circuit board 20, while the second positioning component 50 is mainly used for the visual and precise alignment and fixing of the flexible electrode 10, thereby working together to improve the welding quality and efficiency of the brain electrode device.

[0085] The first positioning component 40 is provided with a first positioning structure 401, which is at least adapted to restrict the circuit board 20 to the first positioning component 40. It can be understood that after the circuit board 20 is restricted to the first positioning component 40, the spatial positions of the plurality of second pads 21 on the circuit board 20 are fixed.

[0086] The second positioning component 50 is provided with a second positioning structure 501, which is at least adapted to restrict the flexible electrode 10 to the second positioning component 50. It can be understood that after the flexible electrode 10 is restricted to the second positioning component 50, the spatial position of the multiple first pads 11 on the flexible electrode 10 is fixed.

[0087] The second positioning component 50 has a first position that is aligned and attached to the first positioning component 40 and a second position that is separated from the first positioning component 40.

[0088] Furthermore, when the second positioning component 50 is in the first position, the second positioning structure 501 and the first positioning structure 401 form a positioning cavity. When the brain electrode device is positioned within the positioning cavity, the circuit board 20 and the flexible electrode 10 at least partially abut against each other. It is understood that the positioning cavity formed by the second positioning structure 501 and the first positioning structure 401 ensures that the at least partially abutting circuit board 20 and flexible electrode 10 achieve precise alignment. In the second position, where the second positioning component 50 is separated from the first positioning component 40, all components of the second positioning component 50 do not contact the second positioning component 50.

[0089] Specifically, along the first direction, after the second positioning component 50 is moved to the first position, the second positioning structure 501 is stacked on the first positioning structure 401 and forms a positioning cavity with the first positioning structure 401. The flexible electrode 10, confined within the positioning cavity, will at least partially stack and abut against the circuit board 20, and the multiple first pads 11 and multiple second pads 21 will correspond one-to-one, achieving precise and rapid positioning of the flexible electrode 10 and the circuit board 20. After the flexible electrode 10 and the circuit board 20 are positioned, the multiple first pads 11 and multiple second pads 21 are welded together one-to-one to form multiple conductive connectors 30, thereby obtaining the desired brain electrode device.

[0090] Understandably, the welding positioning device helps to make the positioning between the circuit board 20 and the flexible electrode 10 in the brain electrode device faster and more accurate. Moreover, by setting up multiple welding positioning devices on the production line, multiple flexible electrodes 10 and multiple circuit boards 20 can be positioned and welded in batches, thereby realizing the mass production of brain electrode devices and improving production efficiency.

[0091] In some embodiments, the first positioning structure 401 includes a positioning groove 421. The positioning groove 421 is disposed on the surface of the first positioning component 40 near the second positioning component 50 and is recessed in a direction away from the second positioning component 50. The shape of the positioning groove 421 is adapted to the circuit board 20. The positioning groove 421 can accurately position the plurality of second pads 21 of the circuit board 20 in both horizontal and vertical directions, thereby achieving precise spatial positioning of the plurality of second pads 21 and preventing the plurality of second pads 21 from shifting during the soldering process. Furthermore, the positioning groove 421 is easy to process and the assembly with the circuit board 20 is efficient and convenient.

[0092] In some embodiments, combined Figures 5-8 As shown, the circuit board 20 includes a rigid circuit board, such as a ceramic plate, i.e., a ceramic printed circuit. The shape of the inner wall of the positioning groove 421 can be set to match the overall outline of the ceramic plate.

[0093] Optionally, after the rigid circuit board is integrally fitted into the positioning groove 421, the edge contour of the rigid circuit board is tightly fitted with the inner wall surface of the positioning groove 421 to achieve horizontal positioning of the multiple second pads 21. The upper surface of the rigid circuit board is flush with the upper surface of the first positioning component 40, or flush with the opening of the positioning groove 421, thereby achieving vertical positioning of the second pads 21. For example, the positioning groove 421 can be a square positioning groove 421 with a length of 10mm-25mm × width of 10mm-25mm × depth of 0.5mm-4mm.

[0094] In some other embodiments, combined Figures 9-12 As shown, the circuit board 20 includes a flexible circuit board, such as an FPC board, i.e., a flexible printed circuit. The shape of the inner wall of the positioning groove 421 can be set to match the outer contour of the welding section of the flexible circuit board. The welding section is a welding area of ​​multiple second solder pads 21 provided on the flexible circuit board.

[0095] Optionally, after the soldering segment of the flexible circuit board is integrally fitted into the positioning groove 421, the edge contour of the soldering segment is tightly fitted with the inner wall surface of the positioning groove 421 to achieve horizontal positioning of the second solder pad 21. The upper surface of the soldering segment is flush with the upper surface of the first positioning component 40 or flush with the opening of the positioning groove 421, thereby achieving vertical positioning of the second solder pad 21. For example, the positioning groove 421 can be a square positioning groove 421 with a length of 5mm-15mm × width of 5mm-15mm × depth of 0.2mm-1.3mm, used to fix the soldering segment of the flexible circuit board (such as an FPC board).

[0096] It is particularly emphasized that, regardless of whether it is a rigid circuit board or a flexible circuit board, this application can achieve precise positioning and restriction of multiple second pads 21 on the circuit board 20 in the horizontal and vertical directions by setting a positioning groove 421 that is adapted to the shape of the circuit board 20, so as to provide conditions for rapid and accurate positioning between them and the flexible electrode 10, which is conducive to the high-efficiency production needs of brain electrode devices.

[0097] Optionally, in some embodiments, the first positioning component 40 further includes a base 41 and a punch 42. The base 41 serves as the basic support for the welding positioning device, and the punch 42 is detachably protruded from the surface of the base 41 near the second positioning component 50.

[0098] Specifically, the base 41 has a mounting hole in its central area that matches the punch 42. The punch 42 is mounted over the mounting hole in the central area of ​​the base 41. The distance deviation between the outer edge of the punch 42 and the inner wall of the mounting hole in the base 41 is ≤0.05mm, so that the punch 42 fits tightly against the mounting hole without damaging the base 41 or making it difficult to disassemble due to excessive tightness. The mounting hole reduces the overall weight of the first positioning component 40, making it easier to handle.

[0099] For example, the base 41 can be made from an aluminum alloy frame structure with a thickness of 3mm-5mm and a flatness of ≤0.05mm. The surface of the base 41 is anodized to support other components and ensure overall rigidity.

[0100] For example, the punch 42 can be a square block structure with a thickness of 3mm-5mm.

[0101] Furthermore, a positioning groove 421 is provided on the punch 42 and is recessed in a direction away from the second positioning component 50. The positioning groove 421 provided on the punch 42 is used to directly support and fix the circuit board 20, and is the core component for achieving precise positioning at the welding station. Specifically, the top surface of the punch 42 has a positioning groove 421 that is adapted to the shape of the welding section of the rigid circuit board or the flexible circuit board. The groove depth of the positioning groove 421 along the first direction is consistent with the thickness of the circuit board 20, and the groove width of the positioning groove 421 matches the width and length of the welding section of the rigid circuit board or the flexible circuit board in the horizontal direction. By making the axis of the positioning groove 421 parallel to the length direction of the base 41, precise embedding and positioning of the circuit board 20 can be achieved, ensuring the coaxiality and load-bearing rigidity of the punch 42 and the base 41, while facilitating alignment with external tooling references, effectively improving the positioning accuracy and process matching of the welding station, and ensuring the stability of welding quality.

[0102] Understandably, when it is necessary to position circuit boards 20 of different sizes or types, it is only necessary to remove the punch 42 with the positioning groove 421 and replace it with a punch 42 that has a positioning groove 421 that matches the circuit board 20 to be soldered.

[0103] Optionally, in some embodiments, to facilitate the assembly of the base 41 and the punch 42, the base 41 and the punch 42 can be detachably connected together by a fastening component 43. The fastening component 43 may include a combination of fasteners (such as screws or bolts) and fixing holes 431. The fixing holes 431 are provided through the punch 42 and the base 41, and internal threads are provided in the fixing holes 431. The screw is inserted into the fixing holes 431 and tightened by engaging with the internal threads.

[0104] The fastening component 43 serves as a mechanical connection channel between the base 41 and the punch 42, and the two are rigidly fixed by fixing screws. The axis of the fixing hole 431 coincides with the center of the four corners of the base 41 and the punch 42 (positional deviation ≤0.03mm), ensuring the installation consistency of the punch 42 and the base 41.

[0105] Optionally, in some embodiments, the surface of the punch 42 near the second positioning component 50 is provided with a first protrusion 71. The first protrusion 71 includes at least three protrusions 71 arranged in a triangular pattern. This triangular arrangement provides a stable three-point positioning reference as an alignment reference for the first positioning component 40. The multiple first protrusions 71 are used to form a first guide component 70 that guides the second positioning component 50 to move to a first position along a first direction. The distance between the axis of the first protrusion 71 and the edge of the base 41 is 1 mm, the positional deviation is ≤0.01 mm, and the spacing between each protrusion 71 and its corresponding hole is strictly consistent to ensure assembly consistency of the components.

[0106] For example, the first protruding post 71 is a cylindrical steel post of a certain height. The first protruding post 71 can be made of GCr15 bearing steel, and the surface is hardened. The surface roughness Ra of the post body is ≤0.2μm to ensure smooth sliding.

[0107] Optionally, in some embodiments, to facilitate more precise and rapid installation of the punch 42 onto the base 41, a second guide component 44 may be provided between the punch 42 and the base 41.

[0108] Specifically, the second guide assembly 44 includes a second protrusion 441 and a guide hole 442. The second protrusion 441 can be disposed on at least one of the base 41 and the punch 42, and the guide hole 442 can be disposed on the other of the base 41 and the punch 42 (i.e., one of them, or both). The depths of the second protrusion 441 and the guide hole 442 are matched. Thus, by lowering the second protrusion 441 along the guide hole 442 until the punch 42 abuts against the base 41, the base 41 and the punch 42 can be detachably fastened together by the fastening member 43.

[0109] Optionally, at least two second protrusions 441 are spaced apart on one diagonal of the top surface of the base 41, with the axis of the second protrusion 441 12mm-14mm away from the edge of the base 41 (positional deviation ≤0.01mm), serving as the alignment reference between the base 41 and the punch 42. Guide holes are provided on the punch at the corresponding positions. The cooperation between the second protrusions 441 and the guide holes 442 ensures the installation consistency between the punch 42 and the base 41.

[0110] Understandably, the diagonal distribution and spacing of the second protrusion 441 match the basic structure to ensure the installation accuracy of the punch 42 and the base 41.

[0111] For example, the second protruding post 441 is a cylindrical steel post of a certain height. The second protruding post 441 can be made of GCr15 bearing steel, and the surface is hardened. The surface roughness Ra of the post body is ≤0.2μm to ensure smooth sliding.

[0112] Optionally, in some embodiments, combined with Figures 5-6 and Figure 9 , Figure 11 As shown, along the second direction, the first positioning component 40 includes at least one first groove 402. The first groove 402 is recessed along the second direction on the inner wall surface of at least one side of the positioning groove 421 and communicates with the positioning groove 421. That is, the first groove 402 communicates with the positioning groove 421, providing sufficient operating space for the placement and removal of the circuit board 20. In other words, the first groove 402 facilitates the operator to use corresponding clamping tools to fit the circuit board 20 into or remove it from the positioning groove 421.

[0113] Optionally, in some embodiments, combined with Figure 9 and Figure 11 As shown, along the third direction, the first positioning component 40 includes at least one second groove 61, which is disposed on at least one side of the positioning groove 421, that is, a second groove 61 is provided on one side or opposite sides, and does not overlap with the first groove 402.

[0114] For example, the second groove 61 may be a long, shallow groove structure for accommodating the flexible electrode 10 and / or the extension of the flexible circuit board to prevent damage to the flexible electrode 10 and the extension of the flexible circuit board during welding.

[0115] Understandably, when the brain electrode device is a combination of a flexible circuit board and a flexible electrode 10, a second groove 61 needs to be provided on both sides of the positioning groove 421. In this case, the extension of the flexible electrode 10 that is misaligned in the welding area can extend from one of the second grooves 61 to form a welding positioning device, while the portion of the flexible circuit board that is misaligned in the welding section can extend from the other second groove 61 to form a welding positioning device. When the brain electrode device is a combination of a rigid circuit board and a flexible electrode 10, only a second groove 61 needs to be provided on one side, and it is sufficient that the extension of the flexible electrode 10 that is misaligned in the welding area can extend from the second groove 61 to form a welding positioning device.

[0116] In some embodiments, the second positioning component 50 includes a clearance space, which is disposed opposite to the second positioning structure 501 and communicates with the positioning cavity. Thus, multiple first pads 11 and multiple second pads 21 can be welded together one-to-one along the clearance space. Positioning before welding is completed by a welding positioning device, making positioning faster and more accurate. The clearance space allows for direct welding of the flexible electrode 10 and the circuit board 20, or facilitates touch-up welding of any missed solder joints between the flexible electrode 10 and the circuit board 20. This can be flexibly adjusted according to actual process requirements.

[0117] Optionally, in some embodiments, the clearance space may be an opening that exposes a plurality of first pads 11 on the flexible electrode 10, thereby allowing a soldering operator to solder the first pads 11 and the second pads 21 together along the clearance space.

[0118] In some embodiments, combined with Figure 5 , Figures 7-8 as well as Figures 9-10 , Figure 12As shown, along the first direction, the second positioning component 50 includes a first surface 503 adjacent to the first positioning component 40. The second positioning structure 501 includes a contour marking region 011 disposed on the first surface 503. The contour marking region 011 is configured to adapt to the shape of the flexible electrode 10 so as to restrict the flexible electrode 10 to the second positioning component 50 by attaching the flexible electrode 10 to the contour marking region 011.

[0119] Understandably, the contour marking area 011 and the positioning groove 421 are arranged to form a positioning cavity and are aligned, so that when the second positioning component 50 is located in the first position aligned and attached to the first positioning component 40, the brain electrode device composed of the circuit board 20 and the flexible electrode 10 can be at least partially confined within the positioning cavity, and the circuit board 20 and the flexible electrode 10 in the positioning cavity are stacked and abutted to form a conductive connector 30.

[0120] Optionally, the contour marking area 011 is formed by the contour line provided on the first surface 503, and the flexible electrode 10 can be attached and accommodated in the contour marking area 011 as a whole. The edge contour of the flexible electrode 10 coincides with the contour line of the contour marking area 011, and the lower top surface of the flexible electrode 10 is flush with the lower top surface of the contour marking area 011. Optionally, the width of the outline is between 0.05mm and 0.1mm (e.g., widths of 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.09mm, 0.1mm, etc.), and the depth of the outline marking area 011 is between 0.01mm and 0.1mm (e.g., depths of 0.01mm, 0.02mm, 0.03mm, 0.04mm, 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.09mm, 0.1mm, etc.). The overall depth of the outline marking area 011 is consistent with the thickness of the flexible electrode 10, and can be freely selected according to the thickness of the flexible electrode 10. Optionally, the entire outline marking area 011 is obtained by laser engraving.

[0121] Optionally, the outline marking area 011 includes a structure where at least one of its color and transparency differs from the other areas of the first surface 503. For example, the color of the outline marking area 011 may be different from the colors of other areas of the first surface 503, or the outline marking area 011 may be set to be more transparent than other areas of the first surface 503. The outline marking area 011 may be created using a laser engraving process. It is particularly emphasized that when the welding area of ​​the flexible electrode 10 and the contact area 14 that contacts the brain tissue are located on opposite sides of the flexible electrode 10 along its thickness direction, to ensure that the contact area 14 can contact the brain tissue downwards after the flexible electrode 10 and the circuit board 20 are welded, the outline marking area 011 is a mirror image of the portion of the flexible electrode 10 where the welding area is located.

[0122] It is understood that, regardless of the form of the outline marking area 011 described above, this application only requires attaching the flexible electrode 10 to the outline marking area 011 and aligning the outer contour of the flexible electrode 10 with the edge contour of the outline marking area 011 to constrain the flexible electrode 10 to the first surface 503 of the second positioning component 50. When the second positioning component 50 moves to the first position and the first surface 503 is tightly attached to the surface of the first positioning component 40, at least partial contact is made between the flexible electrode 10 and the circuit board, thereby aligning the plurality of first pads 11 of the flexible electrode 10 with the plurality of second pads 21 on the circuit board 20 to form corresponding conductive connectors 30.

[0123] Optionally, in some embodiments, to further improve the welding efficiency between the flexible electrode 10 and the circuit board 20, the second positioning structure 501 further includes a positioning plate 52, and the first surface 503 is the surface of the positioning plate 52 near the first positioning component 40. A contour marking area 011 is disposed on the first surface 503 of the positioning plate 52.

[0124] Optionally, the outline marking area 011 includes a through-hole array 502 penetrating the positioning plate 52, which is a perforated mesh structure.

[0125] By setting the positioning plate 52 with the contour marking area 011 and / or the through hole array 502, it is possible to quickly and accurately position the circuit board 20 and the flexible electrode 10, and also to precisely control the coating position and amount of conductive fluid slurry, which is the core component to ensure welding quality.

[0126] For example, the positioning plate 52 can be made of a thin SUS304 stainless steel sheet with a thickness of 0.04mm-0.2mm, such as a sheet structure with a thickness of 0.04mm, 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.09mm, 0.1mm, 0.15mm, or 0.2mm. The surface of the positioning plate 52 is electropolished to achieve a surface roughness Ra ≤ 0.1μm, improving smoothness and flatness, thereby preventing the conductive fluid slurry injected onto the positioning plate 52 from adhering and remaining on it. The surface roughness Ra of the positioning plate 52 can include one of 0.1μm, 0.09μm, 0.08μm, 0.06μm, 0.05μm, or 0.03μm.

[0127] It is particularly important to emphasize that the use of positioning plate 52 screen printing process to replace pressure welding can precisely control the amount of conductive fluid slurry coated (deviation ≤ ±5%), effectively avoiding defects such as uneven solder joint size, hidden cracks, cracks or short circuits / open circuits caused by equipment parameter fluctuations. The welding yield is increased from 70%-80% of the traditional process to more than 95%, making the welding quality more controllable and achieving high precision, high efficiency and low cost control of the welding process.

[0128] Optionally, in some embodiments, the through-hole array 502 corresponds to the positioning plate 52 and is disposed opposite to the contour marking area 011. The through-hole array 502 includes a plurality of first through holes 021 disposed along a first direction. The plurality of first through holes 021 are spaced apart from each other and arranged in an array. The first through holes 021 communicate with the positioning cavity, specifically with the positioning groove 421.

[0129] For example, the first through hole 021 can be a circular through hole or an elliptical through hole, with a hole diameter ranging from 0.1mm to 0.35mm (the hole diameter can be set to one of 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, etc.). The arrangement can be consistent with the multiple second pads 21 on the circuit board 20 and the multiple first pads 11 on the flexible electrode 10. For example, the spacing between several first through holes 021 and adjacent first through holes 021 along a first direction is 0.1mm-1mm (which can be set to one of 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, etc.), and the spacing between several first through holes 021 and adjacent first through holes 021 along a second direction is 0.1mm-1mm (which can be set to one of 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, etc.). That is, the several first through holes 021 are distributed in multiple rows and columns, wherein the spacing between two adjacent first through holes 021 in each row is 0.1mm-1mm, and the spacing between two adjacent first through holes 021 in each column is 0.1mm-1mm. It is emphasized that, in any case, the arrangement of the plurality of first through holes 021 and the plurality of second pads 21 on the circuit board 20 and the plurality of first pads 11 on the flexible electrode 10 are consistent with each other. The detailed specification of any one of the three components is the detailed specification of the other two.

[0130] Specifically, when the circuit board 20 and the flexible electrode 10 are at least partially aligned and abutted before welding, the projected outer contours of the multiple first through holes 021, multiple first pads 11, and multiple second pads 21 coincide along the first direction. Conductive fluid slurry can be simultaneously guided along the through hole array 502 to the multiple first pads 11 and multiple second pads 21, so that the multiple first pads 11 and multiple second pads 21 are welded together one-to-one by the conductive connectors 30 formed by the conductive fluid slurry, ensuring more controllable and efficient welding.

[0131] Optionally, along the axial direction of the first through-hole 021, at least one side of the opening of the first through-hole 021 is provided with a chamfer structure. The chamfer structure may include a 0.02mm × 45° rounded corner or bevel, to prevent conductive fluid paste from sticking to the edge, and to avoid the first through-hole 021 being blocked by the conductive fluid paste stuck to the edge, so that the through-hole array 502 can be reused. The first through-hole 021 may also be at least one of a square hole, a polygonal hole, an elliptical hole, etc., as long as its size is smaller than the size of the second pad 21.

[0132] It is particularly important to note that the positioning plate 52 can be replaced with various through-hole arrays 502 with different through-hole diameters to adapt to the screen printing requirements of flexible electrodes 10 with different pad sizes, achieving "one device with multiple specifications compatibility". At the same time, it can achieve millimeter-level precise quantitative control of the amount of conductive fluid slurry by using different parameter combinations of the through-hole array 502 of the positioning plate 52 to correspond to the volume.

[0133] Optionally, in some embodiments, combined with Figure 8 and Figure 12 As shown, the contour marking area 011 includes a main area 1a and an extension area 1b. Along the length direction of the extension area 1b, one end of the extension area 1b is connected to the main area 1a, and the other end extends to the outer edge of the second positioning component 50 away from the main area 1a. Along the first direction, the projected outer contour of the through-hole array 502 is located within the projected outer contour of the main area 1a. The main area 1a is mainly used for adsorption and positioning of the welding area of ​​the flexible electrode 10 where multiple first pads 11 are provided. After adsorption and positioning, it can be ensured that the multiple first through holes 021 of the through-hole array 502 correspond one-to-one with the multiple first pads 11 on the flexible electrode 10, forming corresponding fluid communication. The extension area 1b can position the area located between the welding area and the contact area 14, and make the contact area 14 extend out of the welding positioning device, improving the positioning accuracy of the flexible electrode 10 without confining the entire flexible electrode 10 within the positioning cavity.

[0134] Optionally, in some embodiments, 75% alcohol is uniformly sprayed onto the outline marking area 011. A flexible electrode 10, with the same size as the outline marking area 011, is then gently placed within the outline marking area 011. Utilizing the surface tension of the alcohol before evaporation, the flexible electrode 10 is positioned quickly and non-contactly, ensuring precise alignment and complete attachment within the outline marking area 011. Furthermore, the surface of the outline marking area 011 is hydrophilically treated (contact angle ≤ 30°) to enhance the micro-adhesive adsorption effect of the adsorption liquid (such as alcohol) on the flexible electrode 10.

[0135] Understandably, the geometric center of the contour marking area 011 coincides with the geometric center of the through-hole array 502 (deviation ≤ 0.02 mm), serving as a visual alignment reference. Through the synergistic effect of the contour marking area 011 and the micro-adhesive adsorption of the adsorption liquid, the flexible electrode 10 is quickly and accurately fixed onto the first surface 503 of the positioning plate 52. The outer edge of the contour marking area 011 completely coincides with the actual edge of the flexible electrode 10 (deviation ≤ 0.02 mm), and the center distance deviation between the outer edge contour line of the contour marking area 011 and the welding area formed by the multiple first pads 11 is ≤ 0.01 mm. The flexible electrode 10 is precisely aligned and completely contained within the contour marking area 011.

[0136] Specifically, after the positioning plate 52 is placed on the first positioning component 40, the flexible electrode 10 directly covers the contour marking area 011. Positioning is completed by intuitively judging the overlap between the edge of the flexible electrode 10 and the contour marking area 011, and multiple second pads 21, without the need for additional measuring tools. The placement of the flexible electrode 10 is directly guided by the visualized contour marking area 011, replacing the complex process of "manual visual inspection + optical positioning system" in traditional processes, and achieving rapid and accurate positioning with "zero tool dependence".

[0137] Optionally, in some embodiments, combined with Figure 5 and Figure 8 As shown, the second positioning structure includes a positioning groove 54, which is disposed on the side of the second positioning component 50 near the first positioning component 40. The positioning groove 54 is adapted to the punch 42, and the first surface 503 is located at the bottom of the positioning groove 54. When the second positioning component 50 is in the first position, the positioning groove 54 is sleeved on the punch 42 and fits against the surface of the punch 42, so that the second positioning component 50 is more stable relative to the first positioning component 40 during the welding process. The positioning groove 54 is sleeved on the punch 42 and the first surface 503 fits against the surface of the punch 42.

[0138] At this time, the punch 42 serves as the first limiting structure, and the limiting groove 54 serves as the second limiting structure. When the second positioning component 50 is in the first position, the first and second limiting structures cooperate to prevent the second positioning component 50 from shifting relative to the first positioning component 40. This not only allows the second positioning component 50 to move more precisely to the first position, but also makes the second positioning component 50 in the first position more stable relative to the first positioning component 40, thereby improving the stability of the circuit board 20 and the flexible electrode 10 during the welding process and preventing them from shifting.

[0139] Understandably, this application, through the cooperation of the punch 42 and the limiting groove 54 provided in the first positioning component 40, can more tightly and stably restrict the second positioning component 50 to the first position after it moves to the first position. The inner wall surface of the limiting groove 54 fits against the inner wall surface of the punch 42, realizing the positioning of the second positioning component 50 in the horizontal and vertical directions, and preventing the second positioning component 50 from shifting relative to the first positioning component 40 during the welding process. Thus, not only can the second positioning component 50 move to the first position more accurately, but the second positioning component 50 in the first position is also more stable relative to the first positioning component 40, thereby preventing the flexible electrode 10 from shifting relative to the circuit board 20, and improving welding accuracy and efficiency.

[0140] Optionally, in some embodiments, the second positioning component 50 includes a clamping member 51, which is detachably clamped to the outer periphery of the positioning plate 52 and can form a limiting groove 54 with the positioning plate 52. The limiting groove 54 is adapted to the punch 42 and can be sleeved on the punch 42 and fit against the surface of the punch 42.

[0141] In other words, during the welding of the circuit board 20 and the flexible electrode 10 using conductive fluid slurry, when it is necessary to replace the through-hole array 502 with different specifications and sizes (i.e., different apertures of the first through-hole 021), only the positioning plate 52 with the different specifications and sizes of the through-hole array 502 needs to be replaced. When the positioning plate 52 is no longer needed, it can be removed from the clamping member 51, and the positioning plate 52 that needs to be used can be clamped by the clamping member 51. Moreover, after the positioning plate 52 is clamped on the clamping member 51, it can form a limiting groove 54 with the clamping member 51, making the assembly efficient and convenient.

[0142] Optionally, in some embodiments, combined with Figures 7-8 and Figure 10 , Figure 12 As shown, the clamping component 51 includes a first frame 511 and a second frame 512. Along the first direction, the first frame 511 is located on opposite sides of the positioning plate 52 and has a clamped state for fixing the positioning plate 52 and a loosened state for removing the positioning plate 52.

[0143] Optionally, the first frame 511 is provided with a first clearance hole 5111. The second frame 512 is provided with a second clearance hole 5121. The through-hole array 502 is located within the space formed by the inner wall of the first clearance hole 5111 and the positioning plate 52, which exposes the upper surface of the positioning plate 52, facilitating the injection of conductive fluid slurry into the through-hole array 502 on the positioning plate 52, so that the conductive slurry can flow along the through-hole array 502 to achieve welding between the first pad 11 and the second pad 21. When the clamping component 51 is in the clamping state, the inner wall of the second clearance hole 5121 on the second frame 512 and the positioning plate 52 form a limiting groove 54, which is adapted to the punch 42.

[0144] Optionally, when the clamping component 51 is in the clamped state, the positioning plate 52 is clamped and embedded between the first frame 511 and the second frame 512. The area of ​​the positioning plate 52 that is not clamped accounts for 80% of the total area of ​​the first frame 511 and the second frame 512, and the geometric center of its through-hole array 502 coincides with the geometric center of the first frame 511 and the second frame 512. By replacing and installing positioning plates 52 with through-hole arrays 502 of different specifications, precise control of the coating position and amount of conductive fluid slurry can be achieved, thereby ensuring welding quality.

[0145] Specifically, in some examples, both the first frame 511 and the second frame 512 are made of metal plates (such as steel plates) of a certain thickness, which facilitates processing. The first frame 511 is made of 3mm-5mm thick steel plate, with countersunk holes at the four corners, and a flat bottom surface that fits against the upper surface of the positioning plate 52. As a clamping structure for the positioning plate 52, it provides stable support for the positioning plate 52 through rigid fastening. The second frame 512 is made of 3mm-5mm thick steel plate, with threaded holes at the four corners of the top surface, and a flat top surface that fits against the lower surface of the positioning plate 52.

[0146] Optionally, the steel plate serving as the first frame 511 and the steel plate serving as the second frame 512 are arranged in parallel (the parallelism between them is ≤0.02mm), and the distance between them is equal to the thickness of the positioning plate 52 plus 0.01mm, so as to ensure that the positioning plate 52 can be evenly clamped by the first frame 511 and the second frame 512.

[0147] Optionally, in some embodiments, the clamping component 51 further includes a locking member 531. The locking member 531 locks the first frame 511 and the second frame 512 into a clamped state or unlocks them into a released state. When the positioning plate 52 needs to be replaced, the first frame 511 and the second frame 512 are unlocked into the released state using the locking member 531. After replacing the new positioning plate 52, the first frame 511 and the second frame 512 are locked into the clamped state using the locking member 531. Disassembly is convenient and assembly is simple.

[0148] For example, the clamping component 51 also includes a matching connecting hole 532. The locking component 531 may specifically include a screw. The connecting hole 532 is disposed through the first frame 511, the positioning plate 52 and the second frame 512. An internal thread matching the external thread on the screw is provided in the connecting hole 532 of one of the first frame 511 and the second frame 512. Then, the screw is inserted into the connecting hole 532 and tightened by engaging the internal thread. The assembly is convenient and the cost is low.

[0149] Optionally, in some embodiments, combined with Figures 7-8 and Figure 9 , Figure 12 As shown, the clamping component 51 includes a third groove 62. Along a third direction, the third groove 62 at least connects to one side of the second clearance hole 5121 of the second frame 512. For example, the groove width of the third groove 62 is 13mm-14.5mm, and the groove thickness is 3mm-5mm, formed by machining. When the limiting groove 54 is formed by the second frame 512 and the positioning plate 52, the third groove 62 can be directly machined onto the second frame 512, making machining convenient.

[0150] Specifically, when the second positioning component 50 is in the first position, the second groove 61 in the first positioning component 40 and the third groove 62 in the second positioning component 50 form a receiving cavity 60. The receiving cavity 60 is connected between the positioning cavity and the outside of the welding positioning device, which can reserve space for the flexible electrode 10 and / or the flexible circuit board to extend out of the welding positioning device, so that the area of ​​the flexible electrode 10 away from the first solder pad 11 can extend out of the welding positioning device along the receiving cavity 60, thereby avoiding damage to the flexible electrode 10 and / or the flexible circuit board.

[0151] Optionally, in some embodiments, combined with Figure 6 and Figure 8 As shown, when the circuit board 20 includes a rigid circuit board, the third groove 62, along a third direction, only connects to one side of the second clearance hole 5121 of the second frame 512, and can be formed with the corresponding second groove 61 on the first positioning component 40 to form a receiving cavity 60, which is in fluid communication with the positioning cavity. The receiving cavity 60 is used to reserve space for the flexible electrode 10 to extend out of the welding positioning device, preventing damage to parts of the flexible electrode 10 other than the welding area.

[0152] Optionally, in some embodiments, combined with Figure 10 , Figure 12 As shown, when the circuit board 20 includes a flexible printed circuit board (FPC), the third groove 62, along a third direction, connects the opposite sides of the second clearance hole 5121 of the second frame 512, and can be formed with the corresponding second groove 61 on the first positioning component 40 to form a receiving cavity 60, which is in fluid communication with the positioning cavity. Further, the side of the extension area 1b of the contour marking area 011 away from the main body area 1a is located within any of the third groove 62, extending along the bottom of the third groove 62 to the outer edge of the second positioning component 50. In this case, the receiving cavity 60 is used to reserve space for the flexible electrode 10 and the flexible circuit board to extend out of the welding positioning device, preventing damage to the flexible electrode 10 and other parts of the flexible circuit board except for the welding area.

[0153] Understandably, since the welding segment with multiple second solder pads 21 on the flexible circuit board is located at one end of the flexible circuit board along its own length, it is only necessary to fit the welding segment into the positioning groove 421, while the other parts of the flexible circuit board extend out of the receiving cavity 60 to form the welding positioning device. The presence of the receiving cavity 60 can prevent other parts of the flexible circuit board that are misaligned in the welding segment from being crushed by the first positioning component 40 and the second positioning component 50. Other parts of the flexible electrode 10 that are misaligned in the welding area can also pass through the welding positioning component along the receiving cavity 60, thereby avoiding being crushed by the first positioning component 40 and the second positioning component 50.

[0154] Optionally, in some embodiments, combined with Figure 12As shown, the positioning plate 52 is provided with corresponding second through holes 72 that are adapted to multiple first protrusions 71. The multiple second through holes 72 are staggered in the through hole array 502. The multiple second through holes 72 are through holes that penetrate the positioning plate 52, including at least three. The at least three second through holes 72 are respectively provided in a one-to-one correspondence with at least three first protrusions 71 (corresponding one-to-one with the number and position of the first protrusions 71). The second through holes 72 and the first protrusions 71 can form a clearance fit. When the fit is achieved, the axis of the corresponding second through hole 72 is completely coincident with the axis of the first protrusion 71.

[0155] Specifically, a plurality of first protrusions 71 disposed on the first positioning component 40 and a plurality of second through holes 72 disposed on the second positioning component 50 constitute a first guide component 70, used to guide the second positioning component 50 to move to a first position along a first direction. Through the first guide component 70, the second positioning component 50 can be guided to move to the first position more accurately and efficiently, thereby achieving precise positioning between the circuit board 20 and the flexible electrode 10, especially in the horizontal direction, achieving sub-millimeter level alignment accuracy. Simultaneously, since the axis of the corresponding second through hole 72 completely coincides with the axis of the first protrusion 71, the coaxiality between the second positioning component 50 and the first positioning component 40 is ensured when the second positioning component 50 moves to the first position.

[0156] It is particularly emphasized that, by setting at least three first protrusions 71 corresponding to the second through holes 72, during the process of moving the second positioning component 50 to the first position, the first protrusions 71 pass through the second through holes 72, thereby guiding the second positioning component 50 to descend to the first position, ensuring precise guidance and positioning. Furthermore, the gap fit between the at least three first protrusions 71 and the second through holes 72 ensures smooth and stable sliding during the guiding process. Overall, the high stability of the alignment process between the first positioning component 40 and the second positioning component 50 is achieved through precise positional constraints, ultimately ensuring rapid and precise alignment between the through hole array 502 and the multiple first pads 11 and multiple second pads 21 during the welding process.

[0157] In summary, it is important to emphasize that the second positioning component 50 is used for precise positioning with the first positioning component 40 and for fixing the flexible electrode 10, effectively avoiding printing misalignment caused by structural deformation. The contour marking area 011 set on the second positioning component 50 provides a visual reference for the placement of the flexible electrode 10. Combined with the precise opening design of the through-hole array 502, it further improves the accuracy of the welding positioning device in the welding position of the flexible electrode 10 and the control of the amount of conductive fluid slurry coated. Furthermore, since the flexible electrode 10 is longer than the welding positioning device, the second frame 512 of the second positioning component 50 has a third groove 62 formed along one or both sides of the third direction to meet the extension requirements of the flexible electrode 10 and the flexible circuit board, preventing the welding positioning device from damaging or injuring the brain electrode device.

[0158] Understandably, after the circuit board 20 and the flexible electrode 10 are constrained and positioned in the welding positioning device, this application can align the multiple first pads 11 of the flexible electrode 10 with the multiple second pads 21 on the circuit board 20 one-to-one, achieving precise and rapid positioning of the flexible electrode 10 and the circuit board 20. After the flexible electrode 10 and the circuit board 20 are positioned, the multiple first pads 11 and the multiple second pads 21 can be welded together one-to-one along the clearance space to obtain the desired brain electrode device.

[0159] In some embodiments, the present invention also provides a welding method, which is implemented by a welding positioning device of the aforementioned structure. By using the welding positioning device of the aforementioned structure to assist in the connection and positioning between the flexible electrode 10 and the circuit board 20, the brain electrode device of the aforementioned structure is obtained. The welding method is described in detail below.

[0160] Specifically, in combination Figures 13-14 As shown, the welding method includes the following steps: Step S1: The circuit board 20 is restricted to the first positioning component 40 by the first positioning structure 401 of the welding positioning device.

[0161] Step S2: The flexible electrode 10 is constrained to the second positioning component 50 by the second positioning structure 501 of the welding positioning device.

[0162] Step S3: Move the second positioning component 50 to the first position so that the multiple first pads 11 of the flexible electrode 10 stacked on the circuit board 20 correspond one-to-one with the multiple second pads 21 on the circuit board 20, so as to solder the multiple first pads 11 and the multiple second pads 21 together.

[0163] Understandably, through the above steps, after the circuit board 20 and the flexible electrode 10 are constrained and positioned in the welding positioning device, the multiple first pads 11 of the flexible electrode 10 can be matched one-to-one with the multiple second pads 21 on the circuit board 20, achieving precise and rapid positioning and alignment of the flexible electrode 10 and the circuit board 20. After the flexible electrode 10 and the circuit board 20 are aligned, conductive fluid paste can be screen-printed and injected to weld the multiple first pads 11 and the multiple second pads 21 together in a one-to-one correspondence, thereby obtaining the desired brain electrode device.

[0164] In some embodiments, in the corresponding welding method, the circuit board 20 is first constrained in the first positioning component 40 by the first positioning structure 401 of the welding positioning device.

[0165] Optionally, the first positioning structure 401 includes a positioning groove 421. The overall shape of the positioning groove 421 is adapted to the circuit board 20, and the circuit board 20 is fitted into the positioning groove 421 so that the outer contour of the edge of the circuit board 20 is in contact with the inner wall surface of the positioning groove 421, and the top surface of the circuit board 20 away from the bottom of the positioning groove 421 is flush with the top surface of the positioning groove 421. In other words, by placing the circuit board 20 in the positioning groove 421, the circuit board 20 can be accurately positioned in both horizontal and vertical directions, and the misalignment of the circuit board 20 during the soldering process can be avoided.

[0166] For example, combined Figure 2 , Figures 5-6 As shown, circuit board 20 includes a rigid circuit board, such as a ceramic plate suitable for implantable brain-computer interface systems. The ceramic plate has a length of 10mm-25mm, a width of 10mm-25mm, and a thickness of 0.5mm-4mm. The ceramic plate to be soldered is placed entirely within the positioning groove 421. The length, width, and depth of the positioning groove 421 are equal to the length, width, and thickness of the ceramic plate. The outer contour of the ceramic plate's edge is fitted against the inner wall of the positioning groove 421, forming a gapless fit between the ceramic plate and the positioning groove 421. The top surface of the ceramic plate is flush with the top surface of the positioning groove 421, achieving precise horizontal positioning of the rigid circuit board and consistent vertical height positioning. At this time, multiple second solder pads 21 on the ceramic plate are evenly arrayed on the surface facing the flexible electrode 10.

[0167] For example, combined Figure 3 , Figures 9-11As shown, circuit board 20 includes a flexible circuit board, such as an FPC board. The flexible circuit board includes a soldering section with multiple second solder pads arrayed on the soldering section. The dimensions of the soldering section of the flexible circuit board range from 10mm to 12mm in length, 8mm to 10mm in width, and 1mm to 2mm in thickness. The soldering section of the FPC board to be soldered is placed in the positioning groove 421. The length, width, and depth of the positioning groove 421 are equal to the length, width, and thickness of the soldering section of the FPC board. The outer contour of the edge of the soldering section of the FPC board is fitted with the inner wall of the positioning groove 421, forming a gapless fit between the soldering section of the FPC board and the positioning groove 421. The top surface of the soldering section of the FPC board is flush with the top surface of the positioning groove 421, achieving precise horizontal positioning and consistent vertical height positioning of the soldering section of the FPC board, and preventing the soldering section from shifting during the soldering process.

[0168] In some embodiments, in the corresponding welding method, the flexible electrode 10 is constrained to the second positioning component 50 by the second positioning structure 501 of the welding positioning device.

[0169] In some embodiments, the second positioning structure 501 includes a contour marking region 011, which is adapted to the shape of the flexible electrode 10, fixing the flexible electrode 10 to the contour marking region 011 and aligning the edge contour of the flexible electrode 10 with the contour line of the contour marking region 011. This achieves precise positioning of the flexible electrode 10.

[0170] Optionally, the first pad 11 is provided with a solder hole 110, which is at least partially opposite to the second pad 21. The conductive fluid paste can extend along the solder hole 110 to the surfaces of multiple first pads 11 and multiple second pads 21. The cured conductive fluid paste can form a conductive network composed of multiple conductive connectors 30 that connect the first pads 11 and the second pads 21.

[0171] Optionally, the second positioning structure 501 includes a positioning plate 52, with a contour marking area 011 disposed on the positioning plate 52. The contour marking area 011 includes a through-hole array 502 corresponding one-to-one with the weld holes 110. Through-hole arrays 502 with different array specifications are provided on different positioning plates 52, and the diameter of the first through hole 021 of the through-hole arrays 502 with different array specifications is different. It can be understood that by adjusting the diameter of the first through hole 021, the amount of conductive fluid slurry can be effectively controlled.

[0172] In this process, after the circuit board 20 is constrained to the first positioning component 40 by the positioning groove 421, the second positioning component 50, which does not carry the flexible electrode 10, is moved to the first position.

[0173] Understandably, at this time, the positioning plate 52 of the second positioning component 50 does not carry the flexible electrode 10, but the multiple first through holes 021 on the positioning plate 52 are aligned with the multiple second pads 21 one by one. The second positioning component 50 can slide down under the guidance of the first guide component 70 to a first position aligned and fitted with the first positioning component 40. The second through holes 72 of the first guide component 70 are clearance-fitted with the first protrusions 71. After manually placing the second positioning component 50 directly above the first positioning component 40, it slowly descends vertically until the first surface 503 of the positioning plate 52 contacts the top surface of the protrusion 42 of the first positioning component 40. At this point, the multiple first through holes 021 are aligned with the multiple second pads 21 one by one.

[0174] The first screen printing is then performed.

[0175] Conductive fluid paste is injected onto the surface of the second pad 21 along the via array 502. At this time, the via array 502 is a first-size array, and the projected area of ​​the first via 021 in the via array 502 is smaller than the projected area of ​​the second pad 21. This setting effectively controls the amount of conductive fluid paste applied, thereby reducing the area of ​​conductive fluid paste coated on the second pad during the first screen printing process. This prevents the conductive fluid paste from overflowing or creeping due to high humidity during soldering, thus reducing the risk of short circuits.

[0176] The conductive fluid slurry is injected into the surface of the positioning plate 52 away from the first positioning component 40, and the conductive fluid slurry is scraped across the through-hole array 502 at a predetermined speed so that the conductive fluid slurry is injected into the surface of the second pad 21 along the through-hole array 502.

[0177] For example, the diameter of the second pad 21 is 0.3mm-0.35mm, and a positioning plate 52 with a first through-hole 021 diameter of 0.1mm-0.15mm is used. That is, 0.1mm-0.15mm is the diameter range of the first through-hole 021 in the first specification through-hole array. When the second pad 21 is attached and aligned with the first through-hole 021, conductive fluid paste is injected onto the surface of the positioning plate 52. A squeegee is used to scrape across the through-hole array 502 of the positioning plate 52 at a certain angle and speed. The conductive fluid paste is coated onto the surface of the second pad 21 along multiple first through-holes 021 to form the first conductive layer 31 of the conductive connector 30. The thickness of the first conductive layer 31 is equal to the thickness of the positioning plate 52, and the coating amount deviation is ±4%. After the first screen printing is completed, the second positioning component 50 is manually and slowly raised vertically until it reaches the second position separated from the first positioning component 40.

[0178] In this process, after the conductive fluid slurry is injected through the first through hole 021 for the first screen printing, the positioning plate 52 is replaced. At this time, the through hole array 502 on the positioning plate 52 is a second specification array, and the orthographic projection area of ​​the first through hole 021 of the through hole array 502 is equal to the orthographic projection area of ​​the second pad 21.

[0179] A volatile adsorbent is sprayed onto the outline marking area 011 on the positioning plate 52. The flexible electrode 10 is adsorbed and fixed onto the outline marking area 011, and the edge contour of the flexible electrode 10 coincides with the contour line of the outline marking area 011. Optionally, the adsorbent can be a volatile liquid such as alcohol, acetone, or ether.

[0180] For example, a positioning plate 52 with a diameter of 0.3mm-0.35mm is used for the first through-hole 021, i.e., 0.3mm-0.35mm is the diameter range of the first through-hole 021 in the second specification through-hole array. 75% alcohol is uniformly sprayed onto the contour marking area 011. The edge of the flexible electrode 10 is picked up with pointed tweezers, and the flexible electrode 10, which matches the shape of the contour marking area 011, is gently placed on the contour marking area 011. Further, the position can be adjusted by visually comparing the contour line of the contour marking area 011 with the edge of the flexible electrode 10 under a microscope, so that the edge of the flexible electrode 10 completely coincides with the contour line. At this time, the flexible electrode 10 is fixed to the contour marking area 011 by the temporary adsorption of alcohol. The multiple first pads 11 of the flexible electrode 10 correspond directly to the multiple second pads 21 on the circuit board 20, and the flexible electrode 10 on the positioning plate 52 maintains a vertical alignment with the circuit board 20.

[0181] In this process, the second positioning component 50 carrying the flexible electrode 10 is left to stand for a preset time, and then the second positioning component 50 is moved to the first position for alignment and bonding.

[0182] For example, after alignment, the assembly is left to stand at room temperature for 10 minutes to allow some of the alcohol to evaporate and reduce residue, thus preventing short circuits caused by excessive wetting of the conductive fluid slurry due to alcohol residue during the welding process. The first positioning component 40 is placed on the heating table of the heating device, and the second positioning component 50 is slowly slid down along the first guide component 70 to the first position manually or through an auxiliary lifting device until the positioning plate 52 is in close contact with the top surface of the punch 42. At this time, the multiple first through holes 021 of the positioning plate 52 are completely aligned with the multiple first solder pads 11, solder holes 110 and multiple second solder pads 21 in the horizontal and vertical directions, forming a vertical projection overlap. The three maintain the stacked abutment structure of positioning plate 52-flexible electrode 10-circuit board 20 in the vertical direction, thereby achieving precise positioning and alignment between circuit board 20 and flexible electrode 10.

[0183] In this process, after the second positioning component 50 carrying the flexible electrode 10 is moved to the first position, pressure is applied to the flexible electrode 10 toward the circuit board 20, forcing the conductive fluid slurry to flow from the surface of the second pad 21 along the solder hole 110 and fill the surface of the first pad 11 under pressure, or to extend from the surface of the second pad 21 to the surface of the first pad 11 and fill the opposite side of the solder hole 110.

[0184] For example, circuit board 20 includes a rigid circuit board, and second positioning component 50 is held in a first position. At this position, positioning plate 52, flexible electrode 10, and rigid circuit board are fully aligned in the horizontal and vertical directions to form a stacked abutment structure. First pad 11 is located on the first side 12 of flexible electrode 10, and first pad 11 does not abut against second pad 21. A custom stainless steel pressure block is used, with a length and width equal to the length and width corresponding to the welding area of ​​flexible electrode 10 plus 2mm, and a thickness of 4mm-5mm. The pressure block is applied vertically to the surface of positioning plate 52, and its boundary extends 2mm beyond the boundary of the effective area of ​​flexible electrode 10, so that the portion of the pressure block extending beyond flexible electrode 10 can limit the flexible electrode 10. Pressure is applied to flexible electrode 10 by pressing the pressure block 1-3 times uniformly (single press / s), forcing the conductive fluid paste on second pad 21 to flow from the surface of second pad 21 along the solder hole and fill the surface of first pad 11 under pressure. After pressing, the pressure block is removed. At this time, the positioning plate 52, the flexible electrode 10 and the rigid circuit board are still aligned and attached, and the conductive fluid slurry has a filling rate of ≥99% in the weld hole without voids, so as to achieve full filling of the weld hole.

[0185] For example, circuit board 20 includes a flexible circuit board, and second positioning component 50 is held in a first position. At this time, positioning plate 52, flexible electrode 10 and flexible circuit board are fully aligned in the horizontal and vertical directions and form a stacked abutment structure. First pad 11 is located on the second side 13 of flexible electrode 10, and first pad 11 abuts against second pad 21. A custom stainless steel pressure block is used, with the length and width of the pressure block = the length and width corresponding to the welding area of ​​flexible electrode 10 + 2mm, and the thickness is 4mm-5mm. The pressure block is applied vertically to the surface of positioning plate 52, and its boundary extends 2mm beyond the boundary of the effective area of ​​flexible electrode 10, so that the part of the pressure block extending beyond flexible electrode 10 can limit the flexible electrode 10. Pressure is applied to flexible electrode 10 by pressing the pressure block 1-3 times uniformly (single press / s), forcing the conductive fluid paste on second pad 21 to extend from the surface of second pad 21 to the surface of first pad 11 under pressure and fill the opposite side of solder hole 110. After pressing, the pressure block is removed. At this time, the positioning plate 52, the flexible electrode 10 and the flexible circuit board are still aligned and attached. The conductive fluid slurry has a filling rate of ≥99% in the weld hole 110 and no voids, so as to achieve full filling of the weld hole 110.

[0186] The conductive fluid slurry is heated and cured to form a conductive connector 30 that is metallurgically bonded to the first pad 11 and the second pad 21.

[0187] For example, the base 41 and punch 42 of the first positioning component 40 are heated by a heating table at a rate of 10°C / min to 80°C-150°C for 0.5-1 hour. The organic carrier in the conductive fluid slurry completely evaporates, and the conductive particles are sintered to form a conductive connector 30 connecting the first pad 11 and the second pad 21, thereby achieving a metallurgical bond between the flexible electrode 10 and the circuit board 20.

[0188] Optionally, the second positioning component 50 is removed to the second position, and an optical microscope is used to inspect and confirm the welding surface of the brain electrode device, including the circuit board 20 and the flexible electrode 10, obtained after the first screen printing welding. The focus is on observing the filling status of the conductive fluid paste (whether there are unfilled areas), the relative position of the flexible electrode 10 (whether it has shifted), the shape of the flexible electrode 10 (whether there are demolding abnormalities such as edge lifting), and the diffusion of the conductive fluid paste (whether it overflows to other adjacent pads and causes a short circuit), so as to complete defect identification and qualified product screening.

[0189] It is particularly important to emphasize that, typically when the circuit board 20 includes a flexible circuit board, since the first pad 11 and the second pad 21 are in close contact, even if only one screen printing is performed to form the conductive connector 30, the welding strength is sufficient for the metallurgical bonding between the flexible electrode 10 and the flexible circuit board. If necessary, multiple screen printing and curing processes can be repeated. When the circuit board 20 includes a rigid circuit board, since the first pad 11 is located on the first side 12 of the flexible electrode 10, there is no close contact between the first pad 11 and the second pad 21. In order to improve the welding reliability and connection strength between the first pad 11 of the flexible electrode 10 and the second pad 21 of the rigid circuit board, at least two screen printing processes of conductive fluid paste must be performed to cure and form the corresponding metallurgical bonding structure.

[0190] Optionally, after the circuit board 20 and the flexible electrode 10 have completed the first screen printing and curing, a second screen printing and curing can be performed as needed.

[0191] In this process, the circuit board 20 of the brain electrode device, after the first screen printing and curing, is placed in the positioning groove 421 to achieve precise horizontal positioning and consistent vertical alignment of the brain electrode device, providing a stable positional reference for the adjustment of the secondary screen printing. The specific alignment requirements are the same as those for the first screen printing and will not be repeated here.

[0192] In this process, the positioning plate 52 is replaced. The through-hole array 502 of the positioning plate 52 is now a third-specification array. The orthographic projection area of ​​the first through-hole 021 in the through-hole array 502 is less than or equal to the orthographic projection area of ​​the second pad 21, and greater than the first area but less than the second area. This is to ensure that even if the conductive fluid paste diffuses to the edge of the first pad 11 or the second pad 21 due to high humidity, it will not exceed the coverage area of ​​the first pad 11 or the second pad 21, thus avoiding the risk of short circuits.

[0193] For example, the positioning plate 52 of the second positioning component 50 is replaced with the first through hole 021 with a diameter of 0.2mm-0.25mm, that is, 0.2mm-0.25mm is the diameter range of the first through hole 021 in the third specification through hole array.

[0194] Then, the second positioning component 50, which does not carry the flexible electrode 10, is moved to the first position.

[0195] Understandably, the second positioning component 50, without the flexible electrode 10, slides down the first guide component 70 to the first position and abuts against the first positioning component 40, until the first surface 503 of the positioning plate 52 contacts the top surface of the flexible electrode 10. At this time, the plurality of first through holes 021 of the through hole array 502 of the positioning plate 52 are completely aligned with the plurality of first pads 11, solder holes 110 and the plurality of second pads 21, and are precisely aligned and covered with the conductive fluid paste cured by the first screen printing, so as to form the reference positioning required for the second screen printing.

[0196] Specifically, conductive fluid slurry is injected along the first through hole 021 onto the surface of the second pad 21 and covers the surface of the first pad 11 or the opposite side of the solder hole 110.

[0197] For example, the second positioning component 50 is held in the first position, and the circuit board 20 includes a rigid circuit board. At this time, the positioning plate 52, the flexible electrode 10, and the rigid circuit board are fully aligned in the horizontal and vertical directions and form a stacked abutment structure. The first pad 11 is located on the first side 12 of the flexible electrode 10, and the first pad 11 does not abut against the second pad 21. Conductive fluid paste is injected into the surface of the positioning plate 52, and a doctor blade is used to scrape across the through-hole array 502 of the positioning plate 52 at a certain angle and a certain speed. The conductive fluid paste is coated onto the stencil area or gap area after the first screen printing through the first through-hole 021 relative to the first specification array through the third specification array. When pressure is applied using the same pressure block as described above, the conductive fluid paste is forced to be injected into the surface of the second pad 21 along the first through-hole 021 and cover the surface of the first pad 11.

[0198] For example, the second positioning component 50 is held in the first position, and the circuit board 20 includes a flexible circuit board. At this time, the positioning plate 52, the flexible electrode 10, and the flexible circuit board are fully aligned in the horizontal and vertical directions and form a stacked abutting structure. The first pad 11 is located on the second side 13 of the flexible electrode 10, and the first pad 11 is in contact with the second pad 21. Conductive fluid paste is injected into the surface of the positioning plate 52, and a squeegee is used to scrape across the through-hole array 502 of the positioning plate 52 at a certain angle and a certain speed. The conductive fluid paste is coated onto the missing area or gap area after the first screen printing through the first through-hole 021 relative to the first specification array aperture of the third specification array. When pressure is applied using the same pressure block as described above, the conductive fluid paste is forced to be injected into the surface of the second pad 21 along the first through-hole 021 and cover the opposite side of the solder hole 110.

[0199] After the conductive fluid slurry fills the gap between the first pad 11, the second pad 21 and the conductive connector 30, it is heated again until the conductive fluid slurry solidifies.

[0200] For example, the second positioning component 50 is removed, while the first positioning component 40 remains stationary. After microscopic inspection confirms that the conductive fluid slurry filling meets the standards, the first positioning component 40 is heated using a heating stage. During heating, the temperature is increased to 80℃-150℃ at a rate of 10℃ / min and maintained for 0.5 hours to 1 hour. After heating, the organic carrier in the conductive fluid slurry completely evaporates, and the conductive particles sinter and solidify, forming a conductive network composed of multiple conductive connectors 30. Ultimately, the conductive fluid slurry forms a sandwich-style continuous conductive path structure from top to bottom: "conductive fluid slurry - flexible electrode 10 - conductive fluid slurry - circuit board 20". Under this structure, the mechanical bonding strength of the welding interface of the brain electrode device obtained by welding is guaranteed, and through precise contour consistency and thickness uniformity control, low contact resistance (≤MΩ level) and high-reliability electrical connection characteristics are achieved.

[0201] In this process, the second positioning component 50 without the flexible electrode 10 is moved to the first position, and the protective reinforcement fluid is injected into the surface of the second pad 21 along the first through hole 021 of the positioning plate 52. This ensures that there is a gap for the flow of the protective reinforcement fluid between the first through hole 021 and the corresponding conductive connector 30, so as to form a protective reinforcement layer covering the surface of the first pad 11, the conductive connector 30 and the surface of the second pad 21.

[0202] For example, the protective reinforcement fluid is set as epoxy resin silicone. After coating with epoxy resin silicone, it is injected from the first through-hole 021 onto the surface of the second pad 21, ensuring a gap for the epoxy resin silicone to flow between the first through-hole 021 and the corresponding conductive connector 30, thus forming a protective reinforcement layer covering the surface of the first pad 11 and the conductive connector 30 to the surface of the second pad 21. Furthermore, it can wrap around the surface of the first side 12 of the flexible electrode 10 to increase the welding strength between the flexible electrode 10 and the circuit board 20.

[0203] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments. Different components and technologies in different embodiments can be freely combined and used with each other.

[0204] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Although this application has disclosed preferred embodiments as above, it is not intended to limit this application. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the technical solution of this application. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A welding positioning device, characterized in that, The welding positioning device is used to assist in the connection and positioning of the brain electrode device, which includes flexible electrodes, a circuit board, and conductive connectors. The welding positioning device includes: A first positioning component, the first positioning component being provided with a first positioning structure, the first positioning structure including a positioning groove for fitting a circuit board; The second positioning component has a second positioning structure that can restrict the flexible electrode to a side surface facing the first positioning component. The second positioning component has a first position that is aligned and attached to the first positioning component and a second position that is separated from the first positioning component. The flexible electrode is provided with a first pad, and the first pad is provided with a solder hole. The circuit board is provided with a second pad. The cured conductive fluid slurry can form the conductive connector that connects the first pad and the second pad. The second positioning structure includes a positioning plate, a contour marking area, and a through-hole array. The surface of the positioning plate near the first positioning component is a first surface. The contour marking area is disposed on the first surface and is used to accommodate the flexible electrode. The contour marking area includes a through-hole array corresponding to the solder hole. The through-hole array penetrates the positioning plate and includes a plurality of first through holes. The first through holes communicate with the positioning groove so that conductive fluid slurry is injected into the surface of the second solder pad along the first through holes. The positioning plates are multiple, and each of the multiple positioning plates is provided with an array of through holes of different array specifications. The diameter of the first through hole in the array of through holes of different array specifications is different, so as to adjust the diameter of the first through hole by replacing the positioning plate located at the first position, thereby controlling the amount of conductive fluid slurry.

2. The welding positioning device according to claim 1, characterized in that, The second positioning component further includes a clamping component, which includes a first frame and a second frame. Along a first direction, the first frame is located on opposite sides of the positioning plate and has a clamping state for fixing the positioning plate and a loosening state for removing the positioning plate. When the clamping component is in the clamping state, the positioning plate is clamped and embedded between the first frame and the second frame.

3. The welding positioning device according to claim 2, characterized in that, When the clamping component is in the clamping state, the geometric center of the through-hole array coincides with the geometric center of the first frame and the second frame.

4. The welding positioning device according to claim 2, characterized in that, The first frame is provided with a first clearance hole, and the through hole array is located within the space formed by the inner wall of the first clearance hole and the positioning plate.

5. The welding positioning device according to claim 1, characterized in that, The first positioning component is provided with a first limiting structure, and the second positioning component is provided with a second limiting structure. When the second positioning component is located at the first position, the first limiting structure and the second limiting structure cooperate to prevent the second positioning component from shifting relative to the first positioning component.

6. The welding positioning device according to claim 5, characterized in that, The first limiting structure includes a punch, which protrudes from the surface of the first positioning component near the second positioning component. The positioning groove is disposed on the punch. The second limiting structure includes a limiting groove, which is disposed on the side of the second positioning component near the first positioning component. The limiting groove is adapted to the punch. When the second positioning component is in the first position, the limiting groove is sleeved on the punch and fits against the surface of the punch.

7. The welding positioning device according to claim 6, characterized in that, The first positioning component also includes a base, and the punch is detachably protruding from the surface of the base near the second positioning component, and the positioning groove is disposed on the punch.

8. The welding positioning device according to claim 6, characterized in that, The second positioning component further includes a clamping component, which can be configured with the positioning plate to form the limiting groove. The limiting groove is adapted to the punch and can be sleeved on the punch and fit against the surface of the punch.

9. The welding positioning device according to any one of claims 1 to 8, characterized in that, The conductive connector is at least partially embedded in the weld hole, and the first pad and the weld hole are asymmetrical elliptical structures.

10. A welding method, characterized in that, The welding method is implemented using the welding positioning device according to any one of claims 1 to 9, and the welding method includes: The circuit board is secured to the first positioning component via a positioning slot; The second positioning component without the flexible electrode is moved to the first position, and the conductive fluid slurry is injected into the surface of the second pad along the through-hole array. At this time, the through-hole array is a first specification array, and the orthographic projection of the first through-hole in the through-hole array has a first area. After the conductive fluid slurry is injected through the first through hole of the through hole array, the positioning plate is replaced. At this time, the through hole array of the positioning plate is a second specification array, and the orthographic projection of the first through hole of the through hole array has a second area. The flexible electrode is adsorbed and fixed to the contour marking area; After the second positioning component carrying the flexible electrode is moved to the first position, pressure is applied to the flexible electrode toward the circuit board, forcing the conductive fluid slurry to fill from the surface of the second pad along the corresponding solder hole to the surface of the first pad, or to extend from the surface of the second pad to the surface of the first pad and fill to the opposite side of the solder hole under the pressure; the conductive fluid slurry is heated and cured to form the conductive connector metallurgically bonded to the first pad and the second pad.

11. The welding method according to claim 10, characterized in that, The first area is smaller than the projected area of ​​the second pad; and / or, the second area is equal to the projected area of ​​the second pad.

12. The welding method according to claim 10, characterized in that, After the conductive fluid slurry is heated and cured to form a metallurgical bond with the first and second pads to the conductive connector, the welding method may further include... Replace the positioning plate. At this time, the through-hole array of the positioning plate is a third specification array. At this time, the orthographic projection of the first through-hole in the through-hole array has a third area. The third area is less than or equal to the orthographic projection area of ​​the second pad, and is greater than the first area and less than the second area. Then, the second positioning component without the flexible electrode is moved to the first position, so that the conductive fluid slurry is injected into the surface of the second pad along the first through hole and covers the surface of the first pad or the opposite side of the solder hole. After the conductive fluid slurry fills the gap between the first pad, the second pad and the conductive connector, it is heated again until the conductive fluid slurry solidifies.

13. The welding method according to claim 10, characterized in that, The step of adsorbing and fixing the flexible electrode to the contour marking area includes: A volatile adsorbent is sprayed onto the outline marking area, and the flexible electrode is adsorbed and fixed onto the outline marking area, so that the edge contour of the flexible electrode coincides with the contour line of the outline marking area.

14. The welding method according to claim 10, characterized in that, The welding method further includes: The conductive fluid slurry is injected into the surface of the positioning plate away from the first positioning component, and the conductive fluid slurry is scraped across the via array at a predetermined speed so that the conductive fluid slurry is injected along the via array to the surface of the second pad; and / or, The step of applying pressure toward the circuit board to the flexible electrode includes, The pressure block is placed on the surface of the positioning plate away from the first positioning component, and the orthographic projection of the flexible electrode along the first direction is located within the orthographic projection of the pressure block along the first direction. Pressure is applied to the flexible electrode by pressing the pressure block.

15. A brain electrode device, characterized in that, The brain electrode device is obtained by welding according to any one of claims 10 to 14.

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