Hall current sensor and preparation method therefor

Abstract

A Hall current sensor and a preparation method therefor, which relate to the technical field of sensors. The method comprises: preparing a substrate (1), wherein the substrate (1) has a first region (11) and a second region (12), the thickness of the substrate (1) corresponding to the first region (11) is greater than the thickness of the substrate (1) corresponding to the second region (12); cutting the substrate (1) to form a frame (2), wherein the frame (2) comprises a current-carrying pin frame (21) formed in the first region (11) and a signal pin (22) formed in the second region (12); providing, at one end of the signal pin (22), a Hall chip (3) that is electrically connected to the signal pin (22); providing a magnetic concentrator (4) on the current-carrying pin frame (21), such that the magnetic concentrator (4) covers the Hall chip (3); and performing injection molding processing on the region of the magnetic concentrator (4) in the frame (2), so as to encapsulate the magnetic concentrator (4), the Hall chip (3), a portion of the current-carrying pin frame (21) and a portion of the signal pin (22). The substrate (1) having different thicknesses is used, and the frame (2) comprising the current-carrying pin frame (21) and the signal pin (22) is formed in a single cutting operation, thereby meeting the production requirements of one-shot injection molding of high-current Hall sensors, improving the accuracy of the relative position between the current-carrying pin frame (21) and the Hall chip (3), and saving on the costs.

Description

Hall current sensor and method for manufacturing the same

[0001] Cross-reference to related applications

[0002] This application claims priority to the Chinese patent application No. 2024113587898, filed on September 27, 2024, and entitled "Hall current sensor and method for manufacturing the same", the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0003] The present application relates to the technical field of sensors, in particular to a Hall current sensor and a method for manufacturing the same. BACKGROUND

[0004] The integrated Hall current sensors on the market at present include small current sensors and large current sensors, wherein the large current sensors are widely used, and the working principle thereof is that when a current passes through the current-carrying pin frame, a magnetic field is generated around the current-carrying pin frame, the magnetic concentrator sleeved on the current-carrying pin frame concentrates the magnetic field, and finally the Hall chip inlaid in the middle of the magnetic concentrator detects the strength of the magnetic field, and then the signal pin outputs a signal, so as to detect the size of the current in the current-carrying pin frame.

[0005] The manufacturing method of the large current sensor is generally as follows: first, the current-carrying pin frame is processed, then the magnetic concentrator is manually or automatically sleeved, then the packaged Hall chip and the signal pin are assembled and installed in the magnetic concentrator, and finally the current-carrying pin frame, the magnetic concentrator and the Hall chip are covered together.

[0006] However, in this manufacturing process, the first injection molding is performed when the Hall chip and the signal pin are assembled, and the second injection molding is performed when the current-carrying pin frame, the magnetic concentrator and the Hall chip are covered; that is, there are two injection molding processes in the production process flow, the manufacturing cycle is long, the process steps are complicated, and two sets of injection molds need to be invested, so the mold cost is high; in addition, in the process of installing the Hall chip and the signal pin in the magnetic concentrator, the relative position of the current-carrying pin frame and the Hall chip is prone to have a large error, so that the Hall sensitive element in the Hall chip deviates from the position of the current-carrying pin frame, thereby affecting the product performance.

[0007] SUMMARY

[0008] Therefore, the present application provides a Hall current sensor and a method for manufacturing the same, so as to solve the problems that the existing large current Hall sensor has two injection molding processes and the relative position of the current-carrying pin frame and the Hall chip is prone to have a deviation, thereby affecting the production efficiency and the product performance.

[0009] In a first aspect, the present application provides a method for manufacturing a Hall current sensor, comprising:

[0010] Preparation of a substrate, the substrate has a first region and a second region, the thickness of the first region corresponding to the substrate is greater than the thickness of the second region corresponding to the substrate;

[0011] Cutting the substrate to form a frame, the frame includes a current-carrying pin frame formed in the first region, and a signal pin formed in the second region;

[0012] Providing a Hall chip at one end of the signal pin, the Hall chip is electrically connected with the signal pin;

[0013] Providing a magnetic concentrator on the current-carrying pin frame, so that the magnetic concentrator covers the Hall chip;

[0014] Injection molding the area where the magnetic concentrator is located in the frame to encapsulate the magnetic concentrator, the Hall chip, part of the current-carrying pin frame and part of the signal pin.

[0015] Beneficial effects: the preparation method of the Hall current sensor of the present application adopts a substrate with different thicknesses, forms a frame including a current-carrying pin frame and a signal pin at one time, meets the different requirements of the current-carrying pin frame and the signal pin for the thickness of the material, and further meets the production requirements of the large-current Hall sensor for one-time injection molding. Compared with the installation of a special-purpose hand tool, the one-time forming of the frame can also position the relative positions of the current-carrying pin frame and the signal pin, which helps to improve the accuracy of the relative position of the current-carrying pin frame and the Hall chip, improve the product consistency, and the Hall chip does not need to be accurately installed to the current-carrying pin frame, that is, there is no need to additionally customize the Hall chip assembly equipment, which helps to save costs and simplify the process.

[0016] In an alternative embodiment, the preparation of the substrate includes:

[0017] Providing a first initial substrate, the thickness of the first initial substrate is uniform;

[0018] Hot rolling the first initial substrate to form a first region and a second region, the thickness of the first region corresponding to the substrate is less than or equal to the thickness of the first initial substrate.

[0019] Beneficial effects: the first initial substrate with a thickness greater than or equal to the thickness of the current-carrying pin frame is selected, such as a copper material with good thermal ductility, the first initial substrate is hot-rolled to obtain a substrate with alternating thicknesses, and then the relatively thick current-carrying pin frame and the relatively thin signal pin are formed at one time through mechanical stamping, which is simple and convenient to prepare, and helps to mass production.

[0020] In an alternative embodiment, the preparation of the substrate includes:

[0021] Providing a second initial substrate;

[0022] Bending treatment is performed at one end of the second initial substrate;

[0023] The bent part is stacked and fixed with the second initial substrate to form a first area in the stacked area, and a second area in the remaining area, the second area corresponding to the thickness of the substrate being equal to the thickness of the second initial substrate.

[0024] Beneficial effects: The second initial substrate with the same thickness as the thinner signal pin is selected, and the plasticity of the copper material is utilized to bend one end and stack and fix it on the original second initial substrate. The stacked thickened area forms a first area to form a current-carrying pin frame, and the original single-layer copper material area forms a second area to form a signal pin. The same thickness of the thinner copper material does not require additional process treatment of the copper material itself, and the stacked and bent part can form a substrate with different thicknesses. The current resistance of the stacked and bent part is small, and the heat generated is also small, which helps to further reduce power consumption.

[0025] In an optional embodiment, the bending process at one end of the second initial substrate includes:

[0026] bending the second initial substrate at one end for the first time;

[0027] bending the first bent part for the second time, and the second bending folds the first bent part in half.

[0028] Beneficial effects: The second initial substrate is bent twice, the thicker first area is composed of three layers of second initial substrates, and the two bent layers are equal in size. The thinner second area is composed of a single layer of second initial substrate. The two-bending process forms a substrate with two thicknesses, which is simple and easy to operate.

[0029] In an optional embodiment, the stacking and fixing of the bent part with the second initial substrate includes: using riveting or welding to stack and fix the bent part with the second initial substrate.

[0030] Beneficial effects: Welding can use laser welding to form a stable substrate structure with different thicknesses through multiple point fixation.

[0031] In an optional embodiment, the magnetic concentrator has an opening, and the current-carrying pin frame is in the shape of a U. The magnetic concentrator is installed on the current-carrying pin frame, and the magnetic concentrator covers the Hall chip, which includes:

[0032] A glue point is provided at one end of the current-carrying pin frame close to the Hall chip;

[0033] The magnetic concentrator is placed in the U-shaped current-carrying pin frame, and the opening of the magnetic concentrator faces the side where the glue point is located;

[0034] The magnetic concentrator is pushed from one side of the current-carrying pin frame to the signal pin side to at least place the Hall chip in the opening of the magnetic concentrator;

[0035] The magnetic concentrator is fixed on the current-carrying pin frame at the glue point.

[0036] Beneficial effects: The device with the functions of glue dispensing, sucking and longitudinal pushing is used to precisely push and fix the magnetic concentrator on the current-carrying pin frame by automatic assembly, which is stable, fast and helps batch production, thereby improving production efficiency and reducing cost.

[0037] In an optional embodiment, the height L of the opening of the magnetic concentrator is greater than the thickness H of the current-carrying pin frame, and the difference between the height L and the thickness H is in the range of 0.1mm-0.2mm.

[0038] Beneficial effects: The height of the opening of the magnetic concentrator is set to have a spacing of 0.1mm-0.2mm with the thickness of the current-carrying pin frame, which facilitates the installation of the magnetic concentrator without causing large shaking and ensures that the magnetic concentrator has enough redundancy to not touch the solder wire of the Hall chip during the installation process, thereby improving the accuracy of the installation of the magnetic concentrator and enhancing the performance consistency of the product.

[0039] In an optional embodiment, the frame further comprises a connecting portion connecting the current-carrying pin frame and the signal pin to limit the relative positions of the current-carrying pin frame and the signal pin.

[0040] Beneficial effects: The connecting portion is arranged in the first area and the second area to connect the current-carrying pin frame and the signal pin, which effectively avoids the relative displacement between the current-carrying pin frame and the signal pin, thereby ensuring the precise installation of the Hall chip and the magnetic concentrator.

[0041] In an optional embodiment, the substrate is cut to form a plurality of current-carrying pin frames in the first area and a plurality of corresponding signal pins in the second area.

[0042] After the area where the magnetic concentrator is located in the frame is injection molded, the method further comprises:

[0043] The connecting portion of the frame is cut to obtain a plurality of separate Hall current sensor units, and any Hall current sensor unit comprises a current-carrying pin frame, a magnetic concentrator, a Hall chip, a signal pin and a plastic sealing structure.

[0044] In the Hall current sensor unit, the end of the current-carrying pin frame away from the magnetic concentrator is bent, and the end of the signal pin away from the magnetic concentrator is bent.

[0045] In a second aspect, the application further provides a Hall current sensor prepared by the preparation method of the Hall current sensor, comprising: a current-carrying pin frame, a signal pin, a Hall chip, a magnetic concentrator, and a plastic sealing structure; the signal pin is arranged in a spaced manner with the current-carrying pin frame, and the thickness of the signal pin is less than the thickness of the current-carrying pin frame; the Hall chip is arranged at one end of the signal pin close to the current-carrying pin frame and is arranged in a spaced manner with the current-carrying pin frame, and the Hall chip is electrically connected with the signal pin; the magnetic concentrator is arranged at one end of the current-carrying pin frame close to the signal pin, and the magnetic concentrator covers at least the Hall chip; and the plastic sealing structure is arranged at the position of the magnetic concentrator to encapsulate the magnetic concentrator, the Hall chip, part of the current-carrying pin frame, and part of the signal pin.

[0046] Beneficial effects: the Hall current sensor of the application has the current-carrying pin frame and the signal pin with different thicknesses which are formed by one-time cutting, the relative positions between the current-carrying pin frame and the signal pin are stable, thereby ensuring the accuracy of the relative positions between the Hall chip installed at one end of the signal pin and the current-carrying pin frame, and the stability and accuracy of the installation of the magnetic concentrator, improving the product consistency; meanwhile, the plastic sealing structure is encapsulated by one-time injection molding, which is simple to prepare and helps to save costs. BRIEF DESCRIPTION OF DRAWINGS

[0047] In order to more clearly illustrate the technical solutions in the specific embodiments or prior art of the application, the following will briefly introduce the drawings needed to be used in the description of the specific embodiments or prior art. Obviously, the drawings described below are some embodiments of the application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0048] FIG. 1 is a flow diagram of the preparation method of the Hall current sensor of the embodiment of the application;

[0049] FIG. 2 is a top view of a substrate in one form of the embodiment of the application;

[0050] FIG. 3 is a front view of a first initial substrate of the embodiment of the application;

[0051] FIG. 4 is a side view of a substrate in one form of the embodiment of the application;

[0052] FIG. 5 is a front view of a second initial substrate of the embodiment of the application;

[0053] FIG. 6 is a schematic view of the embodiment of the application when the second initial substrate is bent;

[0054] FIG. 7 is a front view of a substrate in another form of the embodiment of the application;

[0055] FIG. 8 is a top view of a frame of the embodiment of the application;

[0056] Fig. 9 is a top view of a schematic diagram of the current-carrying pin frame and the signal pin according to an embodiment of the present application;

[0057] Fig. 10 is a side view of a schematic diagram of the magnetic concentrator according to an embodiment of the present application;

[0058] Fig. 11 is a top view of a schematic diagram of the magnetic concentrator according to an embodiment of the present application;

[0059] Fig. 12 is a front view of a schematic diagram of the magnetic concentrator according to an embodiment of the present application;

[0060] Fig. 13 is a side view of a schematic diagram of the magnetic concentrator being set on the current-carrying pin frame according to an embodiment of the present application;

[0061] Fig. 14 is a top view of a schematic diagram of the magnetic concentrator being set on the current-carrying pin frame according to an embodiment of the present application;

[0062] Fig. 15 is a top view of a schematic diagram of the current-carrying pin frame after the adhesive dots are disposed thereon according to an embodiment of the present application;

[0063] Fig. 16 is a top view of a schematic diagram of the magnetic concentrator being placed in the U-shaped space of the current-carrying pin frame according to an embodiment of the present application;

[0064] Fig. 17 is a top view of a schematic diagram of the magnetic concentrator being pushed to be set on the current-carrying pin frame according to an embodiment of the present application;

[0065] Fig. 18 is a side view of a schematic diagram of the magnetic concentrator after the plastic encapsulation is performed on the area where the magnetic concentrator is located according to an embodiment of the present application;

[0066] Fig. 19 is a top view of a schematic diagram of the magnetic concentrator after the plastic encapsulation is performed on the area where the magnetic concentrator is located according to an embodiment of the present application;

[0067] Fig. 20 is a side view of a schematic diagram of the current-carrying pin frame and the signal pin after being bent according to an embodiment of the present application;

[0068] Fig. 21 is a top view of a schematic diagram of the current-carrying pin frame and the signal pin after being bent according to an embodiment of the present application.

[0069] Legend of reference numerals: 10-first initial substrate; 100-second initial substrate; 1-substrate; 11-first region; 12-second region; 2-frame; 21-current-carrying pin frame; 22-signal pin; 23-connection part; 3-Hall chip; 31-chip body; 32-wire; 4-magnetic concentrator; 41-opening; 42-inclined surface; 5-plastic encapsulation structure; 6-adhesive dot. DETAILED DESCRIPTION

[0070] The application will be described in further detail below with reference to the drawings and embodiments. It is to be understood that the specific embodiments described herein are merely illustrative of the application and are not intended to limit the scope of the application. In addition, it is to be understood that, for the purpose of description, only parts related to the application are shown in the drawings rather than all parts. In the following description, the description of well-known structures and techniques is omitted to avoid unnecessarily obscuring the concept of the application. In the drawings, various structural diagrams according to embodiments of the application are shown. These diagrams are not drawn to scale, in which certain details are exaggerated for the purpose of clarity and certain details may be omitted. The shapes of various regions, layers, and the relative size and position relationship between them shown in the drawings are only exemplary, and in actuality, they may deviate due to manufacturing tolerances or technical limitations, and a person skilled in the art can additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs. In the context of the present application, when a layer / element is referred to as being located "on" another layer / element, the layer / element can be directly located on the other layer / element, or there can be an intermediate layer / element between them. In addition, if a layer / element is located "on" another layer / element in one orientation, it can be located "under" the other layer / element when the orientation is reversed.

[0071] In the related art, for a large-current Hall sensor formed by one injection molding, in order to maximize the detection current size while reducing the heat problem, a relatively thick material is usually required for the current-carrying pin frame. However, a relatively thick material for the frame will limit the gap between the materials (the distance between the materials after the frame is made, similar to the spacing between the signal pins) due to processability (generally, the gap is required to be greater than one times the thickness of the copper material), and the signal pins are not suitable for a relatively thick material; if a relatively thin material is used for the current-carrying pin frame, the maximum current that the current-carrying pin frame can withstand will also be limited, which leads to an irreconcilable contradiction between the processability and the measurement range of the product. Of course, a small-current Hall sensor does not require a relatively thick current-carrying pin frame, i.e., there is no such problem.

[0072] To solve this contradiction of the large-current Hall current sensor, the present embodiment provides a preparation method of a Hall current sensor, with reference to FIGS. 1-21, which includes the following steps:

[0073] S101, a base material 1 is prepared, the base material 1 has a first region 11 and a second region 12, the thickness of the first region 11 corresponding to the base material 1 is greater than the thickness of the second region 12 corresponding to the base material 1.

[0074] Referring to FIG. 2, the substrate 1 of the embodiment is made of materials with different thicknesses, and can be made of copper material, which has excellent electrical conductivity, and can be made of high-conductivity heat-resistant copper alloy (KFC). The substrate 1 has regions with different thicknesses in the longitudinal direction of FIG. 2, i.e., in the width direction of the substrate 1. The thicker region is the first region 11, and the thinner region is the second region 12. The substrate 1 with different thicknesses facilitates the manufacture of structures with different thickness requirements.

[0075] S102, the substrate 1 is cut to form the frame 2, which includes the current-carrying pin frame 21 formed in the first region 11 and the signal pin 22 formed in the second region 12.

[0076] Exemplarily, the substrate 1 with different thicknesses is cut by a die-cutting mold to form the frame 2 with integrated thicknesses, as shown in FIG. 8. The thicker first region 11 is cut into the current-carrying pin frame 21, and the thinner second region 12 is cut into the signal pin 22.

[0077] S103, the Hall chip 3 is arranged at one end of the signal pin 22, and the Hall chip 3 is electrically connected to the signal pin 22.

[0078] Referring to FIG. 9, the Hall chip 3 is arranged at the end of the signal pin 22 close to the current-carrying pin frame 21, so as to realize the electrical connection between the Hall chip 3 and the current-carrying pin frame 21, and facilitate the Hall chip 3 to guide the signal out through the signal pin 22. The Hall chip 3 is a magnetic field sensor made according to the Hall effect, and can convert magnetic field information into an electrical signal. The Hall chip 3 generally includes a magnetic field system, a Hall element, and a signal processing circuit integrated in a chip body 31, and a bonding wire 32 configured to output an electrical signal. The magnetic field system can convert an input signal into a magnetic field signal, the Hall element converts the magnetic field signal into an electrical signal, and the signal processing circuit converts the output signal of the Hall element into a signal meeting the application. It can be understood that the Hall chip 3 of the embodiment is an integrated circuit (IC) chip with the Hall effect.

[0079] S104, the magnetic concentrator 4 is arranged on the current-carrying pin frame 21, so that the magnetic concentrator 4 covers the Hall chip 3.

[0080] Referring to FIGS. 10 to 14, the magnetic concentrator 4 is sleeved on the current-carrying pin frame 21, so as to generate a magnetic field around the current-carrying pin frame 21 when current passes through the current-carrying pin frame 21. The magnetic concentrator 4 concentrates the magnetic field, and then detects the strength of the magnetic field through the covered Hall chip 3, so as to obtain the size of the current passing through the current-carrying pin frame 21. Finally, the size of the current passing through the current-carrying pin frame 21 is output through the signal pin 22, so as to realize the detection of the size of the current passing through the current-carrying pin frame 21.

[0081] S105, injection molding the area where the magnetic concentrator 4 in the frame 2 is located to encapsulate the magnetic concentrator 4, the Hall chip 3, part of the current-carrying pin frame 21 and part of the signal pin 22.

[0082] Referring to FIGS. 18 and 19, the area where the magnetic concentrator 4 is located is plastic encapsulated, and the encapsulation of the main functional part of the Hall current sensor is realized by one-time injection molding, high leakage protection is realized, and normal operation of the Hall current sensor is ensured.

[0083] The preparation method of the Hall current sensor of the embodiment adopts a base material 1 with different thicknesses, and the frame 2 including the current-carrying pin frame 21 and the signal pin 22 is formed by one-time cutting, which meets the different requirements of the current-carrying pin frame 21 and the signal pin 22 for the material thickness, and further meets the production requirements of one-time injection molding of the large-current Hall sensor. Compared with the installation of a special-purpose hand tool, the one-time forming of the frame 2 can also position the relative positions of the current-carrying pin frame 21 and the signal pin 22, which helps to improve the relative position accuracy of the current-carrying pin frame 21 and the Hall chip 3, improve product consistency, and the Hall chip 3 does not need to be accurately installed to the current-carrying pin frame 21, that is, there is no need to additionally customize the Hall chip 3 assembly equipment, which helps to save costs and simplify the process.

[0084] As an optional embodiment, the step S101 of preparing the base material 1 includes:

[0085] S1011a, providing a first initial base material 10, the thickness of the first initial base material 10 is uniform;

[0086] S1012a, hot rolling the first initial base material 10 to form a first area 11 and a second area 12, the thickness of the first area 11 is less than or equal to the thickness of the first initial base material 10.

[0087] That is, the first initial base material 10 with a thickness greater than or equal to the thickness of the current-carrying pin frame 21 is selected, such as copper material, and the good thermal ductility of the first initial base material 10 is used to obtain the base material 1 with alternating thick and thin thicknesses shown in FIG. 3 by hot rolling the first initial base material 10, and then the thicker current-carrying pin frame 21 and the thinner signal pin 22 are formed by one-time mechanical stamping, which is simple and convenient to prepare and helps to mass production.

[0088] As another optional embodiment, as shown in FIGS. 5 to 7, the step S101 of preparing the base material 1 can also include:

[0089] S1011b, providing a second initial base material 100;

[0090] S1012b, bending processing is performed on one end of the second initial base material 100;

[0091] S1013b, stack and fix the bent part with the second initial substrate 100 to form the first area 11 in the stacked area, and the rest is the second area 12, and the thickness of the second area 12 is equal to the thickness of the substrate 1.

[0092] That is, the second initial substrate 100 with the same thickness as the thinner signal pin 22 is selected, and the plasticity of the copper material is used to bend one end and stack and fix it on the original second initial substrate 100. The stacked thickened area forms the first area 11 to form the current-carrying pin frame 21, and the original single-layer copper material area is the second area 12 to form the signal pin 22. The same thickness of the thinner copper material does not need additional process treatment to the copper material itself, and after bending and stacking, the substrate 1 with different thicknesses is formed, and the current resistance of the stacked thickened part is small, and the heat is also small, which helps to further reduce power consumption.

[0093] In one embodiment, referring to FIG. 6, the step S1012b includes:

[0094] bending one end of the second initial substrate 100 for the first time;

[0095] bending the part bent for the first time for the second time, and the second bending folds the part bent for the first time.

[0096] That is, the second initial substrate 100 is bent twice, and the thicker first area 11 is composed of three layers of the second initial substrate 100, wherein the two layers of the second initial substrate 100 are equal in size, and the direction of the arrow in FIG. 6 is the direction of the force for stamping and bending. Specifically, the single-layer second initial substrate 100 is made of a copper plate with a thickness of 0.5 mm, and after being bent twice, the substrate 1 with two thicknesses of 1.5 mm and 0.5 mm is formed.

[0097] In one embodiment, referring to FIG. 7, the step S1013b includes: using riveting or welding to stack and fix the bent part with the second initial substrate 100 together, and the welding can use laser welding to finally form the thicker first area 11 and the thinner second area 12, and the arrow in FIG. 7 shows the direction of riveting or laser spot welding.

[0098] Referring to FIGS. 10-17, the magnetic concentrator 4 of the present embodiment has an opening 41, and the current-carrying pin frame 21 is in the shape of U; and the step S104 of mounting the magnetic concentrator 4 on the current-carrying pin frame 21 makes the magnetic concentrator 4 cover the Hall chip 3, which can be automatically assembled by a device with the functions of dispensing, sucking and longitudinal pushing, including the following steps:

[0099] S1041, a glue point 6 is arranged at one end of the current-carrying pin frame 21 close to the Hall chip 3.

[0100] As shown in FIG. 15, the U-shaped current-carrying pin frame 21 includes input ends and output ends arranged vertically on both sides, and a detection end arranged horizontally in the middle. In this embodiment, the detection end in the middle is suitable for arranging the magnetic concentrator 4 to detect the current, so the detection end in the middle is partially glued to form the glue point 6, facilitating the fixation of the magnetic concentrator 4.

[0101] S1042, the magnetic concentrator 4 is placed in the U-shaped current-carrying pin frame 21, and the opening 41 of the magnetic concentrator 4 faces the side where the glue point 6 is located.

[0102] As shown in FIG. 16, the magnetic concentrator 4 is placed in the blank area between the input ends and the output ends of the current-carrying pin frame 21 by mechanical suction, and the opening 41 of the magnetic concentrator 4 is opposite to the detection end, facilitating the pushing of the opening 41 of the magnetic concentrator 4 to the detection end to avoid damage caused by collision.

[0103] S1043, the magnetic concentrator 4 is pushed from one side of the current-carrying pin frame 21 to the side of the signal pin 22 to at least place the Hall chip 3 in the opening 41 of the magnetic concentrator 4.

[0104] As shown in FIG. 17, the magnetic concentrator 4 is pushed into the current-carrying pin frame 21 in the direction indicated by the arrow by using a longitudinal thrust structure, so that the magnetic concentrator 4 covers the detection end of the current-carrying pin frame 21 and the Hall chip 3, so that the enhanced magnetic field signal of the magnetic concentrator 4 is fully transmitted to the Hall chip 3 and converted into an electrical signal output.

[0105] S1044, the magnetic concentrator 4 is fixed on the current-carrying pin frame 21 at the glue point 6.

[0106] In order to facilitate the smooth pushing of the magnetic concentrator 4, the size of the opening 41 of the magnetic concentrator 4 is usually slightly larger than the thickness of the current-carrying pin frame 21, so the magnetic concentrator 4 needs to be moved downward to contact the glue point 6, and then the glue point 6 is cured by methods such as ultraviolet curing or thermal curing, which enhances the stability of the magnetic concentrator 4 and the current-carrying pin frame 21, and also ensures that the magnetic concentrator 4 has enough redundancy to avoid touching the solder wire 32 of the Hall chip 3, ensuring smooth signal output.

[0107] The above-mentioned automatic assembly method precisely fixes the magnetic concentrator 4 on the current-carrying pin frame 21, which is helpful for mass production, thereby improving production efficiency and reducing cost.

[0108] Referring to FIGS. 10 and 13, in this embodiment, the height L of the opening 41 of the magnetic concentrator 4 is greater than the thickness H of the current-carrying pin frame 21, and the difference between the height L and the thickness H is in the range of 0.1mm-0.2mm.

[0109] The height dimension of the opening 41 of the magnetic concentrator 4 is close to the thickness of the thicker current-carrying pin frame 21 in the frame 2, and in this embodiment, it is provided with a spacing of 0.1mm-0.2mm, which facilitates the installation of the magnetic concentrator 4 without causing large shaking, thereby improving the accuracy of the installation of the magnetic concentrator 4 and enhancing the performance consistency of the product. If the spacing is less than 0.1mm, the magnetic concentrator 4 is difficult to be clamped into the current-carrying pin frame 21; if the spacing is greater than 0.2mm, it is easy to cause the problem of not being clamped tightly, thereby causing up and down shaking.

[0110] In addition, referring to FIGS. 10 and 11, the outer wall surface of the opening 41 of the magnetic concentrator 4 is also formed with an inclined surface 42, which facilitates the push assembly of the magnetic concentrator 4 and avoids damage to other structures caused by sharp right-angle structures.

[0111] Referring to FIG. 8, the frame 2 further includes a connecting portion 23 connecting the current-carrying pin frame 21 and the signal pin 22 to limit the relative positions of the current-carrying pin frame 21 and the signal pin 22.

[0112] It can be known that when the current-carrying pin frame 21 and the signal pin 22 are formed by processing the frame 2 from the base material 1, they do not need to be electrically connected in the final product. In this embodiment, the connecting portion 23 with a linear structure is arranged in both the first area 11 and the second area 12 to connect the current-carrying pin frame 21 and the signal pin 22, which effectively avoids the relative displacement between the current-carrying pin frame 21 and the signal pin 22, thereby ensuring the accurate installation of the Hall chip 3 and the magnetic concentrator 4. After the installation is completed, the connecting portion 23 can be removed by cutting to ensure the relative isolation of the current-carrying pin frame 21 and the signal pin 22.

[0113] In one embodiment, in the step S102 of cutting the base material 1, a plurality of current-carrying pin frames 21 are formed in the first area 11, and a plurality of corresponding signal pins 22 are formed in the second area 12; after the step of S105 of performing injection molding treatment on the area of the frame 2 where the magnetic concentrator 4 is located, the method further includes:

[0114] S106, cutting the connecting portion 23 of the frame 2 to obtain a plurality of separate Hall current sensor units, and any Hall current sensor unit includes the current-carrying pin frame 21, the magnetic concentrator 4, the Hall chip 3, the signal pin 22, and the plastic package structure 5;

[0115] S107, for each Hall current sensor unit, the end of the current-carrying pin frame 21 away from the magnetic concentrator 4 is bent, and the end of the signal pin 22 away from the magnetic concentrator 4 is bent.

[0116] Specifically, the frame 2 after injection molding is cut by a cutting rib forming device, that is, the connecting part 23 is cut and removed from the position, and then the input end and the output end of the current-carrying pin frame 21 and the free end of the signal pin 22 in each obtained Hall current sensor unit are bent, as shown in FIGS. 20 and 21, to obtain a single Hall current sensor product.

[0117] The embodiment also provides a Hall current sensor prepared by the preparation method of the Hall current sensor, comprising a current-carrying pin frame 21, a signal pin 22, a Hall chip 3, a magnetic concentrator 4 and a plastic sealing structure 5; the signal pin 22 is arranged in a spaced manner with the current-carrying pin frame 21, and the thickness of the signal pin 22 is less than the thickness of the current-carrying pin frame 21; the Hall chip 3 is arranged at one end of the signal pin 22 close to the current-carrying pin frame 21 and is arranged in a spaced manner with the current-carrying pin frame 21, and the Hall chip 3 is electrically connected with the signal pin 22; the magnetic concentrator 4 is arranged at one end of the current-carrying pin frame 21 close to the signal pin 22, and the magnetic concentrator 4 covers at least the Hall chip 3; and the plastic sealing structure 5 is arranged at the position of the magnetic concentrator 4 to encapsulate the magnetic concentrator 4, the Hall chip 3, part of the current-carrying pin frame 21 and part of the signal pin 22.

[0118] The Hall current sensor of the embodiment has the current-carrying pin frame 21 and the signal pin 22 with different thicknesses formed by one-time cutting, the relative position between the current-carrying pin frame 21 and the signal pin 22 is stable, thereby ensuring the accuracy of the relative position between the Hall chip 3 arranged at one end of the signal pin 22 and the current-carrying pin frame 21, and the stability and accuracy of the magnetic concentrator 4, and improving the product consistency; meanwhile, the plastic sealing structure 5 is encapsulated by one-time injection molding, which is simple to prepare and helps save cost.

[0119] In the above description, the technical details such as the patterning of each layer and etching are not described in detail. However, those skilled in the art should understand that the layers and regions with desired shapes can be formed by various technical means. In addition, those skilled in the art can also design methods that are not exactly the same as the methods described above to form the same structure. In addition, although each embodiment is described above, this does not mean that the measures in each embodiment cannot be used advantageously in combination.

[0120] Although the embodiments of the present application are described in conjunction with the drawings, various modifications and changes can be made by those skilled in the art without departing from the spirit and scope of the present application, and such modifications and changes fall within the scope defined by the appended claims.

Claims

1. A method of manufacturing a Hall current sensor, characterized by, The application relates to a method for manufacturing a Hall sensor, comprising the following steps: preparing a base material (1) having a first area (11) and a second area (12), wherein the thickness of the first area (11) corresponding to the base material (1) is greater than the thickness of the second area (12) corresponding to the base material (1); cutting the base material (1) to form a frame (2), wherein the frame (2) comprises a current-carrying pin frame (21) formed in the first area (11) and signal pins (22) formed in the second area (12); arranging a Hall chip (3) on one end of the signal pins (22), wherein the Hall chip (3) is electrically connected to the signal pins (22); arranging a magnetic concentrator (4) on the current-carrying pin frame (21), so that the magnetic concentrator (4) covers the Hall chip (3); performing injection molding on the area of the frame (2) where the magnetic concentrator (4) is arranged, so as to encapsulate the magnetic concentrator (4), the Hall chip (3), part of the current-carrying pin frame (21) and part of the signal pins (22).

2. The method of producing a Hall current sensor according to claim 1, wherein The method for preparing the base material (1) comprises the following steps: providing a first initial base material (10) having a uniform thickness; hot-rolling the first initial base material (10) to form a first area (11) and a second area (12), wherein the thickness of the first area (11) corresponding to the base material (1) is less than or equal to the thickness of the first initial base material (10).

3. The method of claim 1, wherein the Hall current sensor is prepared by a process comprising: The method for preparing the base material (1) comprises the following steps: providing a second initial base material (100); bending one end of the second initial base material (100); stacking the bent part and the second initial base material (100) to form a first area (11) in the stacked area, and a second area (12) in the remaining area, wherein the thickness of the second area (12) corresponding to the base material (1) is equal to the thickness of the second initial base material (100).

4. The method of claim 3, wherein the Hall current sensor is prepared by a process comprising: The method for bending one end of the second initial base material (100) comprises the following steps: firstly bending one end of the second initial base material (100); secondly bending the part bent in the first step, so that the part bent in the first step is folded in half.

5. The method of claim 4, wherein the Hall current sensor is prepared by a process comprising: The method for stacking the bent part and the second initial base material (100) comprises the following steps:

6. The method of producing a Hall current sensor according to claim 1, wherein riveting or welding the bent part and the second initial base material (100) together. The magnetic concentrator (4) has an opening (41), and the current-carrying pin frame (21) is in a U shape; the method for arranging the magnetic concentrator (4) on the current-carrying pin frame (21) so that the magnetic concentrator (4) covers the Hall chip (3) comprises the following steps: arranging a glue point (6) on one end of the current-carrying pin frame (21) close to the Hall chip (3); placing the magnetic concentrator (4) in the U-shaped current-carrying pin frame (21), wherein the opening (41) of the magnetic concentrator (4) faces the side where the glue point (6) is arranged. Pushing the magnetic concentrator (4) to move from the side of the current-carrying pin frame (21) to the side of the signal pin (22) to at least place the Hall chip (3) in the opening (41) of the magnetic concentrator (4); Fixing the magnetic concentrator (4) on the current-carrying pin frame (21) at the glue point (6).

7. The method of producing a Hall current sensor according to claim 6, wherein The height L of the opening (41) of the magnetic concentrator (4) is greater than the thickness H of the current-carrying pin frame (21), and the difference between the height L and the thickness H is in the range of 0.1mm-0.2mm.

8. The method of producing a Hall current sensor according to any one of claims 1 to 7, characterized in that, The frame (2) further comprises: A connecting part (23) connecting the current-carrying pin frame (21) and the signal pin (22) to limit the relative position of the current-carrying pin frame (21) and the signal pin (22).

9. The method of claim 8, wherein the Hall current sensor is prepared by a process comprising: The cutting of the substrate (1) forms a plurality of current-carrying pin frames (21) in the first area (11) and a plurality of corresponding signal pins (22) in the second area (12); After the injection molding of the area in the frame (2) where the magnetic concentrator (4) is located, further comprising: Cutting the connecting part (23) of the frame (2) to obtain a plurality of separate Hall current sensor units, any of which comprises a current-carrying pin frame (21), a magnetic concentrator (4), a Hall chip (3), a signal pin (22), and a plastic package structure (5); Bending the end of the current-carrying pin frame (21) away from the magnetic concentrator (4) and the end of the signal pin (22) away from the magnetic concentrator (4) in the Hall current sensor unit.

10. A Hall current sensor produced by the method of producing a Hall current sensor according to any one of claims 1 to 9, characterized by Comprise: A current-carrying pin frame (21); A signal pin (22) is arranged in a spaced manner with the current-carrying pin frame (21); the thickness of the signal pin (22) is less than the thickness of the current-carrying pin frame (21); A Hall chip (3) is arranged at the end of the signal pin (22) close to the current-carrying pin frame (21) and is arranged in a spaced manner with the current-carrying pin frame (21); the Hall chip (3) is electrically connected with the signal pin (22); A magnetic concentrator (4) is arranged at the end of the current-carrying pin frame (21) close to the signal pin (22); the magnetic concentrator (4) covers at least the Hall chip (3); A plastic package structure (5) is arranged at the position of the magnetic concentrator (4) to package the magnetic concentrator (4), the Hall chip (3), part of the current-carrying pin frame (21), and part of the signal pin (22).

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