Current sensor, manufacturing process and assembling process

Abstract

The invention discloses a current sensor, a manufacturing process and an assembling process, relates to the technical field of current sensors, and is used for solving the problem that an onboard three-phase two-path current sensor is difficult to maintain when a Hall chip is damaged. The current sensor comprises a shell, an annular iron core, a Hall chip, a cover plate and a chip pin; a mounting cavity is formed in the shell, the mounting cavity is provided with an opening, a detection cavity is formed in the shell, and the forming direction of the detection cavity is perpendicular to the opening direction of the mounting cavity; the annular iron core surrounds the detection cavity by one circle and is arranged in the shell, and a notch is formed in the part, located in the mounting cavity, of the annular iron core; the Hall chip is arranged in the mounting cavity, the Hall chip is located at the notch, the Hall chip is provided with a chip pin, the chip pin penetrates through the cover plate and extends out of the shell, and the end, located outside the shell, of the chip pin is used for being connected with a target PCB; and the cover plate is arranged at the mounting cavity, abuts against the Hall chip and is fixedly connected with the shell.

Description

Technical Field

[0001] This application relates to the technical field of current sensors, and particularly to a current sensor, a manufacturing process, and an assembly process. Background Art

[0002] An on-board three-phase two-way current sensor is a device used to measure two currents in a three-phase circuit, and is usually applied to electronic devices or systems that require precise monitoring and control of three-phase currents. It is connected to the circuit board of the target to be monitored through a terminal block, and transmits information into the control system of the target to achieve negative feedback.

[0003] A current sensor based on the Hall effect usually has a Hall chip and an internal PCB board. The Hall chip is installed on the internal PCB board, and the internal PCB board is usually encapsulated with the housing of the current sensor by means of welding, injection molding, etc.

[0004] However, during the use of the current sensor, the Hall chip is a frequently damaged component; at this time, since the internal PCB board covers the upper side of the Hall chip and is extremely easy to damage when removed by heating, most on-board three-phase two-way current sensors will choose to be directly replaced when the Hall chip is damaged due to the consideration of maintenance difficulty and cost. Summary of the Invention

[0005] This application provides a current sensor, a manufacturing process, and an assembly process, which are used to solve the problem that it is difficult to repair an on-board three-phase two-way current sensor when the Hall chip is damaged.

[0006] This application provides a current sensor, including a housing, a toroidal core, a Hall chip, a cover plate, and chip pins; an installation cavity is formed on the housing, the installation cavity has an opening, a detection cavity penetrating the housing is formed inside the housing, the detection cavity is used to accommodate a copper bar to be detected, and the opening direction of the detection cavity is perpendicular to the opening direction of the installation cavity; the toroidal core surrounds the detection cavity for one week and is arranged inside the housing, and a notch is formed on the part of the toroidal core located in the installation cavity; the Hall chip is arranged in the installation cavity, the Hall chip is located at the notch, the Hall chip has chip pins, the chip pins penetrate the housing and extend outside the housing, and one end of the chip pins located outside the housing is used to be connected to the target PCB board; the cover plate is arranged at the installation cavity, the cover plate abuts against the Hall chip, and the cover plate is fixedly connected to the housing and the chip pins.

[0007] The Hall chip in the current sensor in this application is cooperatively installed with the toroidal iron core. By placing the copper busbar to be detected in the detection cavity within the toroidal iron core, the current within the copper busbar to be detected acts on the toroidal iron core and the Hall chip to generate a specific voltage signal. In this solution, the Hall chip of the current sensor is fixed in the installation cavity within the housing through a cover plate, and is directly connected to the target PCB board through the chip pins, avoiding the use of an internal PCB board, reducing costs, and simplifying the process.

[0008] When the Hall chip detects a change in the magnetic field, it generates corresponding electrical signals, which can be output through its pins. Directly connecting the pins of the Hall chip to the lines of the external circuit board can form a complete signal transmission path, enabling the electrical signals generated by the Hall chip to be transmitted to the external circuit board for subsequent processing, amplification, display, etc., and can reduce the solder joints and the signal transmission path of the chip, reducing the risk of false soldering and EMC risk.

[0009] This structure avoids the PCB board, and there is no need for specific encapsulation between the Hall chip and the cover plate. When the Hall chip is damaged, the cover plate can be directly removed to replace the Hall chip, avoiding the problem that the internal PCB board of the current sensor is extremely easy to be damaged when removed by heating, making the current sensor easy to repair when the Hall chip is damaged; omitting the internal PCB board of the current sensor makes the overall structure of the current sensor more compact, effectively saving installation space, and being more suitable for precision devices with limited space.

[0010] At the same time, directly connecting the chip pins of the Hall chip to the target PCB board shortens the signal transmission path, reduces the interference and loss that the signal may suffer during transmission, helps to improve the quality and stability of signal transmission, thereby enhancing the measurement accuracy and reliability of the entire system; by canceling the internal PCB board of the current sensor, the heating effect of the internal PCB board and the heat dissipation barrier to the Hall chip are avoided, which is beneficial to reducing the working temperature of the Hall chip, improving the heat dissipation performance, and further extending the service life of the Hall chip and ensuring the stability of its performance.

[0011] In some embodiments of this application, a card slot is formed in the installation cavity, and the Hall chip is snap-fitted into the card slot. The card slot can provide an accurate installation position for the Hall chip, ensuring its position accuracy within the cavity, thereby ensuring the precise relative position relationship between the chip and the toroidal magnetic core, which is beneficial to improving the accuracy and stability of current measurement; the snap-fitting method can make the Hall chip stably installed in the card slot and is convenient for loading and unloading, facilitating assembly and later maintenance and replacement.

[0012] In some embodiments of the present application, a plurality of chip pins are provided, and the plurality of chip pins are distributed in parallel. The plurality of chip pins can be respectively connected to the positive power supply, negative power supply, and signal output terminal, so as to provide a stable working power supply for the Hall chip, and at the same time accurately transmit the electrical signal detected by the chip to the target PCB board to achieve the functions of current measurement and monitoring.

[0013] In some embodiments of the present application, a plurality of avoidance holes are provided on the cover plate, and the plurality of avoidance holes correspond to the plurality of chip pins one by one, and each chip pin passes through an independent avoidance hole. The avoidance holes provide precise positioning for the chip pins, ensuring that each terminal can accurately pass through the corresponding hole, thereby ensuring the accuracy and stability of the connection between the chip pins and the external circuit; at the same time, the avoidance holes facilitate the installation of the cover plate.

[0014] In some embodiments of the present application, two detection cavities are provided, the opening directions of the two detection cavities are the same and the two detection cavities are spaced apart, and an annular iron core is provided outside each detection cavity, and an installation cavity is formed at the notch of each annular iron core. A Hall chip, a cover plate, and chip pins are provided on each installation cavity.

[0015] The two detection cavities can perform double measurements on the same copper bar to be detected. By comparing or fusing the data obtained from the two detection cavities, the measurement error can be effectively reduced, and the accuracy and reliability of the measurement can be improved; if one of the detection cavities fails, the other detection cavity can still work normally and continue to provide current detection data to ensure the normal operation of the system, improve the stability and fault tolerance of the system, and the redundant detection cavity can improve the reliability of the current sensor.

[0016] In some embodiments of the present application, at least two positioning posts and positioning holes are provided on the housing, and the at least two positioning posts and positioning holes are both used for the positioning and installation of the current sensor and the target component. The positioning posts and positioning holes can provide precise position references for the installation of the housing, ensure that it is accurately installed at the predetermined position during the installation process, and avoid installation deviations; the plurality of positioning structures can position the housing from different directions and positions, further improving the accuracy and accuracy of the positioning, and ensuring the overall accuracy and performance of the equipment after installation.

[0017] A manufacturing process of a current sensor, in which an annular iron core, an embedded ring, and a plastic material are integrally injection-molded to form a housing, a positioning hole is formed in the area where the plastic ring is located, an installation cavity and a detection cavity are formed on the housing, and a card slot is formed in the installation cavity; the Hall chip is snapped into the card slot, and after the cover plate is buckled on the housing, the Hall chip is fixed to the housing; the avoidance holes on the cover plate are correspondingly installed with the chip pins, and the cover plate is fixed to the housing.

[0018] Integrally injection-molding a toroidal iron core, an embedded ring, and a plastic material to form a housing can make the housing have good integrity and stability, ensuring the accurate relative positions between various parts. By providing an installation cavity, a card slot, and a positioning hole on the housing, and a clearance hole on the cover plate, precise positioning and secure installation of the Hall chip can be achieved, ensuring the electrical connection and mechanical stability between components. This design makes the assembly process more convenient, conducive to improving production efficiency and reducing assembly difficulty.

[0019] In some embodiments of the present application, bolt holes are provided on the housing so that the bolt holes and the embedded ring jointly form fixing holes. The bolt holes and the embedded ring cooperate with each other to fix the installation components from different positions and directions, improving the connection stability between the current sensor and the target component.

[0020] An assembly process for a current sensor involves positioning through the positioning holes on the current sensor and a specified area on the target component, and relatively fixing the current sensor and the target component through a connecting piece; soldering all the protruding chip pins on the current sensor to corresponding positions on the PCB board inside the target component; calibrating; and passing the copper bar to be detected of the target component through the detection cavity of the housing of the current sensor.

[0021] The cooperation between the positioning holes and the specified area on the target component can ensure that the current sensor is installed at the accurate position on the target component, guaranteeing the relative position accuracy with other components. Soldering the chip pins of the current sensor to the corresponding positions on the PCB board inside the target component can form a good electrical connection, ensuring the accurate transmission of voltage signals, reducing signal interference and transmission loss.

[0022] Through calibration, the measurement accuracy of the current sensor can be determined, calibrated, and adjusted so that it can accurately measure the current value of the copper bar to be detected in the target component. And calibrating after the installation of the current sensor and the target component is completed can avoid installation errors caused by premature calibration, enabling better accuracy when measuring the same current, which is beneficial for use in precision equipment.

[0023] In some embodiments of the present application, the current sensor has two detection cavities, and the same copper bar to be detected passes through the two detection cavities, so that the two detection cavities respectively form a main detection cavity and an auxiliary detection cavity.

[0024] The redundant detection cavities can perform double measurements on the same copper bar to be detected, effectively reducing measurement errors and improving the accuracy and reliability of measurement. If one of the detection cavities fails, the other detection cavity can still work normally and continue to provide current detection data, ensuring the normal operation of the system, improving the stability and fault tolerance of the system, and enhancing the reliability of the current sensor. Description of the Drawings

[0025] The accompanying drawings are used to provide a further understanding of the technical solution of the present invention, and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present invention, and do not constitute a limitation to the technical solution of the present invention.

[0026] Figure 1 It is an exploded schematic diagram of a current sensor provided by an embodiment of the present application.

[0027] Figure 2 It is an assembly schematic diagram of a current sensor provided by an embodiment of the present application.

[0028] Figure 3 It is a schematic diagram of the production and installation process of a current sensor provided by an embodiment of the present application.

[0029] Reference numerals: 1 - housing; 11 - installation cavity; 111 - card slot; 12 - detection cavity; 13 - positioning hole; 14 - embedding ring; 2 - annular iron core; 21 - notch; 3 - Hall chip; 4 - cover plate; 41 - avoidance hole; 5 - chip pin. Detailed implementation manners

[0030] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0031] It should be noted that all the directional indications (such as up, down, left, right, front, back,...) in the embodiments of the present invention are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0032] The terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, unless otherwise stated, the meaning of "a plurality" is two or more.

[0033] In the description of the present application, it should be noted that unless otherwise clearly specified and defined, the terms "connected" and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances. Additionally, when describing pipelines, the "connected" and "coupled" used in the present application have the meaning of conducting. The specific meaning needs to be understood in combination with the context.

[0034] In the embodiments of the present application, words such as "exemplary" or "for example" are used to represent examples, illustrations, or explanations. Any embodiment or design solution described as "exemplary" or "for example" in the embodiments of the present application should not be construed as being more preferred or having more advantages than other embodiments or design solutions. Rather, the use of words such as "exemplary" or "for example" is intended to present relevant concepts in a specific manner.

[0035] The on-board three-phase two-way current sensor is a device for measuring two-way currents in a three-phase circuit, and is usually applied to electronic devices or systems that require precise monitoring and control of three-phase currents. It is connected to the circuit board of the target to be monitored through terminals, and transmits information into the control system of the target to achieve negative feedback.

[0036] The current sensor based on the Hall effect usually has a Hall chip and an internal PCB board. The Hall chip is mounted on the internal PCB board, and the internal PCB board is usually encapsulated with the housing of the current sensor by means of soldering, injection molding, etc.

[0037] However, during the use of the current sensor, the Hall chip is an element that is often damaged. At this time, since the internal PCB board covers the upper side of the Hall chip and is extremely easy to be damaged when removed by heating, for the consideration of maintenance difficulty and cost, most on-board three-phase two-way current sensors will choose to directly replace when the Hall chip is damaged.

[0038] To this end, please refer to Figure 1 , the present application provides a current sensor, including a housing 1, a toroidal core 2, a Hall chip 3, a cover plate 4, and chip pins 5.

[0039] Please refer to Figure 1 , an installation cavity 11 is formed on the housing 1. The installation cavity 11 has an opening. A detection cavity 12 penetrating the housing 1 is formed inside the housing 1. The detection cavity 12 is used to accommodate the copper bar to be detected. The opening direction of the detection cavity 12 is perpendicular to the opening direction of the installation cavity 11. The housing 1 can be made of plastic material or other materials that are easy to mold.

[0040] Please refer to Figure 1, The installation cavity 11 is a space formed inside the housing 1 and has an opening. The installation cavity 11 is mainly used to install the internal components of the current sensor, such as the Hall chip 3. The opening facilitates the installation and disassembly of the components, making it convenient for assembly during the production process and for replacing or maintaining the components during subsequent repairs. Therefore, the cross-section of the opening can be larger than the cross-sectional area of the components installed in the installation cavity 11.

[0041] Please refer to Figure 1 , The detection cavity 12 is a cavity that penetrates the housing 1 inside the housing 1. Its main function is to accommodate the copper bar to be detected. When there is current passing through the copper bar to be detected, a magnetic field will be generated inside the detection cavity 12. The current sensor uses principles such as the Hall effect to measure the magnitude of the current in the circuit by detecting this magnetic field. The opening direction of the detection cavity 12 is perpendicular to the opening direction of the installation cavity 11, thus facilitating the configuration of the toroidal core.

[0042] Please refer to Figure 1 , The toroidal iron core 2 surrounds the detection cavity 12 for one week and is arranged inside the housing 1. A notch 21 is formed on the part of the toroidal iron core 2 located in the installation cavity 11. The toroidal iron core 2 surrounds the detection cavity 12 for one week and is arranged inside the housing 1. Its main function is to enhance the magnetic field generated by the copper bar to be detected. When there is current passing through the copper bar to be detected, a magnetic field will be generated around it. The toroidal iron core 2 can gather and guide these magnetic fields, making the magnetic field more concentrated and stable, thereby improving the detection sensitivity and accuracy of the current sensor.

[0043] Please refer to Figure 1 , The toroidal structure helps to form a closed magnetic circuit, reducing the leakage of the magnetic field into the external environment, reducing the interference of the external magnetic field on the detection result, and at the same time avoiding the influence of the magnetic field of the current sensor itself on other surrounding electronic devices, improving the electromagnetic compatibility of the entire system.

[0044] Please refer to Figure 1 , The notch 21 formed on the part of the toroidal iron core 2 located in the installation cavity 11 is mainly for installing the Hall chip 3. The Hall chip 3 needs to be placed in a position where the magnetic field change can be accurately detected. The existence of the notch 21 provides a suitable installation space for the Hall chip 3, enabling it to be fully coupled with the magnetic field generated by the toroidal iron core 2, thereby accurately detecting the change in the magnetic field intensity and then converting it into a corresponding electrical signal to achieve the measurement of the current.

[0045] Please refer to Figure 1 , The notch 21 is also the air gap of the toroidal core. This air gap will affect the induction range and induction accuracy of the Hall chip 3 arranged inside the toroidal core. Therefore, the size design of the notch 21 needs to be reasonable.

[0046] Please refer to Figure 1, the Hall chip 3 is disposed in the installation cavity, and the Hall chip 3 is located at the notch 21. It works based on the Hall effect. When there is a current passing through the Hall chip 3, a voltage proportional to the magnetic field strength will be generated in the direction perpendicular to the current and the magnetic field, that is, the Hall voltage. In this current sensor, the toroidal iron core 2 enhances and concentrates the magnetic field generated by the copper busbar to be detected. The Hall chip 3 is placed at the notch 21 of the iron core, and can accurately detect this magnetic field and convert it into a corresponding electrical signal. By processing and analyzing the electrical signal, the magnitude of the current in the copper busbar to be detected can be obtained.

[0047] The Hall chip 3 has chip pins 5. The chip pins 5 penetrate through the housing 1 and extend outside the housing 1. One end of the chip pins 5 located outside the housing 1 is used to connect to the target PCB board. The chip pins 5 are fixedly connected to the Hall chip 3. This structure belongs to the conventional structure of the Hall chip 3 to transmit the electrical signal detected by the Hall chip 3.

[0048] The end of the Hall chip penetrates through the cover plate 4 and extends outside the housing 1, which is convenient for connecting to the target PCB board, so as to transmit the signal detected by the current sensor to the PCB board for further processing, amplification, display or control and other operations.

[0049] The connection between the chip pins 5 and the Hall chip 3 is an integral connection. This connection structure depends on the Hall chip 3. The connection between the chip pins 5 and the target PCB board can be welding to ensure the stability of the connection, the stability of signal and power transmission.

[0050] Please refer to Figure 1 , the magnetic field at the notch 21 is relatively concentrated and uniform, which is beneficial for the Hall chip 3 to accurately sense the magnetic field change, improving the measurement accuracy and reliability. At the same time, being installed in the installation cavity can be protected by the housing 1, avoiding interference and damage from external factors. The Hall chip 3 can be located at the center position of the notch 21, or it can also have a certain error range for easy installation.

[0051] Please refer to Figure 1 and Figure 2 , the cover plate 4 is disposed at the installation cavity 11. The cover plate 4 abuts against the Hall chip 3, and the cover plate 4 is fixedly connected to the housing 1. The cover plate 4 can be made of PA66-GF30 or PBT-GF30, which has relatively high strength and toughness and can effectively protect the Hall chip 3.

[0052] In some other examples, the cover plate 4 can also be made of other materials, such as aluminum alloy material or ceramic material.

[0053] Please refer to Figure 2, the size of the cover plate 4 can be customized according to the size of the installation cavity 11, such as slightly larger than the opening of the installation cavity 11 to ensure complete coverage of the opening; the cover plate 4 can be U-shaped so that the bent edges on both sides of the cover plate 4 can be snap-fitted on the side walls of the housing 1 on both sides of the opening.

[0054] The cover plate 4 and the housing 1 can be snap-connected, or can be adhesively bonded with glue or fixed with screws, and these connection methods can relatively fix the cover plate 4 and the housing 1.

[0055] Please refer to Figure 1 , in the current sensor of the present application, the Hall chip 3 is cooperatively installed with the toroidal iron core 2. By placing the copper bar to be detected in the detection cavity 12 in the toroidal iron core 2, the current in the copper bar to be detected acts on the toroidal iron core 2 and the Hall chip 3 to generate a specific voltage signal; the Hall chip 3 of the current sensor in this solution is fixed in the installation cavity 11 in the housing 1 through the cover plate 4 and is directly connected to the target PCB board through the chip pins 5, avoiding the use of an internal PCB board, reducing the cost and simplifying the process.

[0056] Please refer to Figure 1 , when the Hall chip 3 detects a magnetic field change, corresponding electrical signals will be generated, and these signals can be output through its pins. Directly connecting the pins of the Hall chip 3 to the circuit of the external circuit board can form a complete signal transmission path, enabling the electrical signals generated by the Hall chip 3 to be transmitted to the external circuit board for subsequent processing, amplification, display, etc., and can reduce the solder joints and the chip signal transmission path, reducing the risk of false soldering and EMC risk.

[0057] Please refer to Figure 1 , this structure avoids the PCB board, and the Hall chip 3 and the cover plate 4 do not require specific encapsulation. When the Hall chip 3 is damaged, the cover plate 4 can be directly removed to replace the Hall chip 3, avoiding the problem that the internal PCB board of the current sensor is extremely easy to be damaged when removed by heating. When the Hall chip 3 of the current sensor is damaged, it is convenient for maintenance; the internal PCB board of the current sensor is omitted, making the overall structure of the current sensor more compact, effectively saving installation space, and being more suitable for precision devices with limited space.

[0058] Please refer to Figure 1At the same time, the chip pin 5 of the Hall chip 3 is directly connected to the target PCB board, which shortens the signal transmission path and reduces the interference and loss that the signal may receive during the transmission process, which helps to improve the quality and stability of signal transmission, thereby improving the measurement accuracy and reliability of the entire system; by eliminating the built-in PCB board of the current sensor, the heating effect of the built-in PCB board and the heat dissipation barrier to the Hall chip 3 are avoided, which is conducive to reducing the operating temperature of the Hall chip 3, improving the heat dissipation performance, and thus extending the service life of the Hall chip 3 and ensuring the stability of its performance.

[0059] It can be explained that the target component can be a component using the current sensor provided by this solution, such as a motor, a power module, an inverter, etc.; the target PCB board can be a circuit board inside the target component, which can be a circuit board connected to a controller, or other integrated circuit board; the target PCB board should belong to the circuit control and signal processing part of the entire electrical system. Various electronic components, such as resistors, capacitors, chips, etc., are integrated on the target PCB board. These components are connected together through printed circuits to form specific circuit functions.

[0060] Please refer to Figure 1 In some examples, a slot 111 is formed in the mounting cavity 11, and the Hall chip 3 is snapped into the slot 111. The slot 111 can provide an accurate mounting position for the Hall chip 3, ensuring its positional accuracy within the cavity, thereby ensuring the precise relative positional relationship between the chip and the annular magnetic core, which is conducive to improving the accuracy and stability of current measurement. The snap-fit method can ensure that the Hall chip 3 is firmly mounted in the slot 111 and is easy to load and unload, facilitating assembly and subsequent maintenance and replacement.

[0061] In some examples, the slot 111 can be rectangular in shape. This shape matches the shape of the Hall chip 3, providing a stable engagement effect and keeping the Hall chip 3 in a fixed position within the slot 111, preventing shaking or displacement during use that could affect detection accuracy. The rectangular slot 111 is also easy to process and manufacture, ensuring dimensional accuracy and consistency.

[0062] The card slot 111 can be a recessed structure with a certain depth, which can be slightly greater than the thickness of the Hall chip 3 to ensure that the chip can be completely embedded in the card slot 111 and that the chip will not be subjected to additional squeezing or warping after the cover plate 4 is installed.

[0063] Since the housing 1 in this solution is formed by injection molding, the slot 111 can be directly formed during the injection molding process; or it can be formed through secondary processing after the injection molding is completed.

[0064] Please refer to Figure 1, in some examples, there are multiple chip pins 5, and the multiple chip pins are distributed in parallel. The multiple chip pins 5 can respectively include a positive power supply, a negative power supply, and a signal output terminal, so as to provide a stable working power supply for the Hall chip 3, and at the same time accurately transmit the electrical signals detected by the chip to the target PCB board to achieve the functions of current measurement and monitoring.

[0065] In some examples, the way of using multiple chip pins 5 externally connected to the Hall chip 3 is a conventional way; the multiple chip pins can be exactly the same, which is convenient for installation and assembly.

[0066] The number of chip pins can be adjusted according to needs. For example, a current-type chip only includes two pins, and a voltage-type chip can be set to 3 or 4 pins according to needs. The number of pins of the chip depends on the specific type of the Hall chip 5.

[0067] Please refer to Figure 1 , in some examples, there are multiple avoidance holes 41 provided on the cover plate 4, and each chip pin 5 passes through an independent avoidance hole 41. The avoidance holes 41 provide precise positioning for the chip pins 5, ensuring that each terminal can accurately pass through the corresponding hole, thus ensuring the accuracy and stability of the connection between the chip pins 5 and the external circuit; at the same time, the avoidance holes 41 can facilitate the installation of the cover plate 4.

[0068] Exemplarily, since different types of Hall chips 5 have different numbers and positions of chip pins 5, the number and position of the avoidance holes 41 should be set according to the number and position of the chip pins 5 on the Hall chip 5 during design to ensure that the two can cooperate with each other.

[0069] Please refer to Figure 1 , in some examples, there are two detection cavities 12, the opening directions of the two detection cavities 12 are the same and the two detection cavities 12 are spaced apart. An annular iron core 2 is provided outside each detection cavity 12, and an installation cavity 11 is formed at the notch 21 of each annular iron core 2. A Hall chip 3, a cover plate 4, and chip pins 5 are provided on each installation cavity 11.

[0070] The two detection cavities 12 can perform double measurements on the same copper bar to be detected. By comparing or fusing the data obtained from the two detection cavities 12, the measurement error can be effectively reduced, and the accuracy and reliability of the measurement can be improved; if one of the detection cavities 12 fails, the other detection cavity 12 can still work normally and continue to provide current detection data to ensure the normal operation of the system, improve the stability and fault tolerance of the system, and the redundant detection cavities 12 can improve the reliability of the current sensor.

[0071] In some examples, the two detection cavities 12 can be exactly the same, and there should be a certain distance between the corresponding toroidal cores 2 in the two detection cavities 12 to avoid mutual influence; the opening directions of the two detection cavities 12 can be exactly the same, and the inside can adopt the same circuit, so as to facilitate the stability of the detection results and enable the fault tolerance provided by the redundant detection cavities 12 to be realized.

[0072] Please refer to Figure 1 and Figure 2 , in some examples, at least two positioning posts and positioning holes 13 are provided on the housing 1, and the at least two positioning posts and positioning holes are both used for the positioning and installation of the current sensor and the target component.

[0073] The positioning posts and the positioning holes 13 can provide an accurate position reference for the installation of the housing 1, ensure that it is accurately installed at the predetermined position during the installation process, and avoid installation deviation; multiple positioning structures can position the housing 1 from different directions and positions, further improving the accuracy and precision of positioning, and ensuring the overall accuracy and performance of the equipment after installation.

[0074] In some examples, the positioning posts are columnar protrusions (not marked in the figure) formed at specific positions during the injection molding of the housing, and the number of positioning posts can be two, three or other numbers.

[0075] The positioning holes 13 are hole-shaped structures provided on the housing 1 for determining the position of the housing 1 during the installation process. They can be through holes, threaded holes or other hole structures. Their main function is to cooperate with other positioning components to ensure the accuracy and consistency of the installation of the housing 1, ensure that it can be accurately docked and assembled with the surrounding components or equipment, so that the structure of the entire system is more stable and the electrical connection is more reliable.

[0076] Please refer to Figure 1 , in some examples, the shape of the positioning holes 13 can be circular or square; the positioning holes 13 can be located on the edge, center, side wall or bottom wall of the housing 1. The number of positioning holes 13 can be two, three, four or five, and the sizes of different positioning holes 13 can be the same or different.

[0077] Exemplarily, the current sensor provided by this solution has the above-mentioned housing 1, toroidal core 2, Hall chip 3, cover plate 4 and chip pins 5, and does not have an internal circuit board. Therefore, the positioning of the Hall chip 3 is only achieved through the card slot 111 in the housing 1 and the cover plate 4.

[0078] At this time, the current sensor does not encapsulate an internal PCB board. Therefore, when replacing the Hall chip 3, the disassembly process is simpler, and it also avoids damaging the internal PCB board and various disassembly and installation problems caused by the internal PCB board.

[0079] In addition, when a conventional current sensor is disassembled, the built-in PCB board is not only easily damaged, but there are also installation problems with some terminals between the Hall chip 3 and the built-in PCB board, and between the built-in PCB board and the PCB board of the target component. In addition, after the Hall chip 3 is replaced on the built-in PCB board, regardless of whether the built-in PCB board is damaged during maintenance, the PCB board needs to be recalibrated. The current value generated by the recalibrated built-in PCB board has a new deviation from the original current value due to the position of the Hall chip 3, the calibration of the built-in PCB board, and the deviation of the installation position, which is not conducive to the subsequent use of the current sensor.

[0080] Please refer to Figure 1 , in some examples, in order to ensure that the Hall chip 3 is well encapsulated and improve the dust-proof ability, a corresponding sealing structure can be provided between the cover body and the housing 1. For example, a sealing gasket can be formed on the cover body to improve the sealing effect between the cover body and the housing 1, making the sealing effect between the cover plate 4 and the housing 1 better.

[0081] Please refer to Figure 3 , a manufacturing process of a current sensor, in which the toroidal core 2, the embedded ring 14 and the plastic material are integrally injection-molded to form the housing 1. The positioning holes 13 are formed in the area where the plastic ring is located. The installation cavity 11 and the detection cavity 12 are formed on the housing 1, and the card slot 111 is formed in the installation cavity 11. The Hall chip 3 is snapped into the card slot 111, and after the cover plate 4 is buckled on the housing 1, the Hall chip 3 is fixed to the housing 1. The avoidance holes 41 on the cover plate 4 are correspondingly installed with the chip pins 5, and the cover plate 4 is fixed on the housing 1.

[0082] Please refer to Figure 3 , integrally injection-molding the toroidal core 2, the embedded ring 14 and the plastic material to form the housing 1 can make the housing 1 have good integrity and stability, ensuring the accurate relative positions of all parts. By providing the installation cavity 11, the card slot 111 and the positioning holes 13 on the housing 1, and the avoidance holes 41 on the cover plate 4, accurate positioning and firm installation of the Hall chip 3 can be achieved, ensuring the electrical connection and mechanical stability between all components. This design makes the assembly process more convenient, which is conducive to improving production efficiency and reducing the assembly difficulty.

[0083] In some examples, if the toroidal core 2 needs to be encapsulated and protected in the traditional way, additional encapsulation materials and process steps are required. When integrally injection-molded, the plastic material directly wraps the toroidal core 2, eliminating the need for a separate encapsulation layer, reducing the material cost and the encapsulation process cost, and at the same time simplifying the product structure and making the overall structure more compact.

[0084] The injection-molded plastic material itself has good insulation performance, which can effectively isolate the toroidal core 2 from the outside world, preventing it from causing electrical short circuits with other components or being affected by corrosion, wear, etc. of the external environment. Moreover, the plastic is tightly combined with the core, and the protection effect is better than that of a separately provided encapsulation layer, and it can better adapt to different working environments.

[0085] Without the interference of an additional encapsulation layer, the electromagnetic performance of the toroidal core 2 is more stable. The integrally injection-molded plastic housing 1 can be optimized according to electromagnetic requirements during design, reducing problems such as electromagnetic interference or magnetic circuit distortion caused by the encapsulation layer, which helps to improve the measurement accuracy and reliability of devices such as current sensors.

[0086] In some examples, the integrally injection-molded process forms the toroidal core 2, the embedded ring 14, and the plastic material in one mold at one time. Compared with the traditional method of separately manufacturing each component first and then assembling them, the production process and time are greatly reduced. There is no need to perform complex operations such as separately processing, assembling multiple components, and encapsulating the toroidal core 2, improving production efficiency and being suitable for large-scale industrial production.

[0087] During the injection molding process, the mold can precisely control the size and shape of the housing 1, ensuring the fitting accuracy between the toroidal core 2, the embedded ring 14, and the plastic housing 1. Compared with separately manufacturing and then assembling, the integrally injection-molded process can effectively avoid errors generated during the assembly process, making the positional relationship between components more accurate, which is beneficial to improving the consistency and quality stability of the product.

[0088] At the same time, it avoids complex operations such as coating and winding that may occur in the encapsulation process of the toroidal core 2, as well as problems such as poor adhesion between the subsequent encapsulation layer and the core. The integrally injection-molded process is relatively simple and easy to control, reducing the process difficulty and the skill requirements for operators, and also reducing the defective rate of products caused by complex processes.

[0089] In some examples, when the Hall chip 3 is fixed to the housing 1 after the housing 1 is fastened with the cover plate 4, according to the mounting holes of the Hall chip 3 and the thickness of the plastic housing 1, self-tapping screws with appropriate diameter and length are selected, and before screwing in the self-tapping screws, a drill bit slightly smaller than the diameter of the self-tapping screw is first used to pre-drill holes in the plastic housing 1 to avoid cracking of the housing 1.

[0090] Please refer to Figure 1, in some examples, bolt holes are provided on the housing 1 so that the bolt holes and the embedding ring 14 together form fixing holes. The bolt holes cooperate with the embedding ring 14, and can position the mounting component from different positions and directions, and can fixedly assemble the current sensor with a specified position of the target component, more accurately determine the position of the mounting component, reduce the deviation during the installation process, improve the overall installation accuracy, and improve the connection stability between the current sensor and the target component.

[0091] In some examples, internal threads can be provided inside the embedding ring 14 to form the above-mentioned bolt holes, or a smooth ring surface can be provided inside the embedding ring 14 to form a pin shaft connection relationship with a specified position on the target component. At this time, the positioning posts near the threaded holes can form a positioning relationship with the specified holes of the target component, and a fixed connection relationship can be formed between the current sensor and the target component through the connection between the threaded holes and the corresponding threaded parts.

[0092] The three self-tapping threaded holes provided on the housing 1 can form a mating relationship with a specified position on the target component, so that the current sensor forms a fixed relationship with the PCB board in the MCU of the client (target component).

[0093] It can be explained that in the above description, both positioning holes 13 and fixing holes and threaded holes are provided on the housing 1. At this time, the above hole structures can be the same hole structure or different hole structures. The specific number, position, and type of holes can be set according to different fixing requirements, but the positioning requirements are usually positioned through the above-mentioned positioning posts extending from the housing 1.

[0094] An assembly process of a current sensor positions through the positioning holes 13 on the current sensor and a specified area on the target component, and relatively fixes the current sensor and the target component through a connecting piece; solders all the protruding chip pins on the current sensor to corresponding positions on the PCB board in the target component; calibrates; passes the copper bar to be detected of the target component through the detection cavity 12 of the housing 1 of the current sensor.

[0095] The cooperation between the positioning holes 13 and the specified area on the target component can ensure that the current sensor is installed at the accurate position of the target component and ensure the relative position accuracy with other components; soldering the chip pins of the current sensor to the corresponding positions on the PCB board in the target component can form a good electrical connection, ensure the accurate transmission of voltage signals, and reduce signal interference and transmission loss.

[0096] Calibration can determine the measurement accuracy of the current sensor, calibrate and adjust it so that it can accurately measure the current value of the copper bar to be detected in the target component. Calibrating after the installation of the current sensor and the target component is completed can avoid installation errors caused by premature calibration, have better accuracy when measuring the same current, and is beneficial for use on precision equipment.

[0097] It should be added that calibration is an important process in the related technology of current sensors.

[0098] Calibration refers to the process of determining the quantitative relationship between the output signal of the current sensor and the actual input current through a series of precise operations and measurements, and calibrating and adjusting the sensor to ensure the accuracy and reliability of its measurement.

[0099] During the production process of current sensors, due to the influence of various factors, such as the discreteness of component parameters and the differences in manufacturing processes, there may be certain deviations in their output characteristics. Through calibration, the difference between the actual output and the theoretical value of the sensor can be accurately measured and adjusted to make its measurement accuracy meet the specified requirements.

[0100] Before calibration, usually a standard current source with a precision higher than the accuracy requirement of the current sensor to be calibrated is prepared. The current sensor is connected to the standard current source and measuring instruments (such as digital multimeters, oscilloscopes, etc.) according to the specified circuit connection method to ensure reliable connection and avoid problems such as poor contact or short circuit. It is carried out under specified environmental conditions. For example, environmental parameters such as temperature, humidity, and air pressure should meet the usage requirements of the sensor. Generally speaking, the environmental temperature should be controlled at 20°C ± 5°C, and the relative humidity is preferably 40% - 60% to reduce the influence of environmental factors on the sensor performance.

[0101] Then apply the standard current and record the output signal. Adjust the gain of the amplifier on the built-in PCB board, the zero potentiometer, etc. according to the standard current and the recorded output signal to make the output characteristics of the sensor meet the requirements of the calibration curve, so that the output voltage signal is the same as the standard current data.

[0102] The above calibration procedure is the calibration process during the conventional production of current sensors, and all the above processes are completed during the production stage.

[0103] However, when calibrating the current sensor, usually the fixing holes on the housing 1 are installed on the predetermined mold, and then calibrated through the above process. However, the fixing holes usually adopt a clearance thread fit relationship. Even for the fixing holes on the same housing 1, there will be deviations when installed at different positions, and this deviation is a non-linear deviation, which is difficult to make up for by data correction means.

[0104] After the current sensor is sold and installed on the target component, most of the deviations during the calibration and use of the current sensor will be amplified, reducing the accuracy of the current sensor. For precision devices, the accuracy requirements cannot be met.

[0105] However, for the current sensor provided by this solution, since there is no built-in PCB board inside during the manufacturing stage, there is no calibration process during the production stage.

[0106] According to the above description, the calibration of the current sensor is a process after the positioning on the target component is completed. At this time, all adjustments to the component during the calibration process are carried out on the PCB board of the target component, so that the current information output by the target component can be exactly the same as the information during calibration, thus greatly improving the accuracy of the current sensor.

[0107] When disassembling and repairing the current sensor, such as replacing the Hall chip 3, recalibration can be carried out, that is, the detection accuracy of the current sensor can be guaranteed after reinstallation during maintenance.

[0108] Generally speaking, calibrating the current sensor after installing it at a fixed position on the target component can make the sensor in the same environmental and position conditions as in the actual work during the calibration process. This can take into account various influences that the target component may have on the sensor, such as magnetic field distribution, temperature change, etc., thereby improving the accuracy of calibration and ensuring that the sensor can measure the current more accurately during actual use.

[0109] Calibrating after installation can avoid measurement errors caused by deviations or uncertainties during the installation process. If calibrated first and then installed, situations such as sensor position offset and angle change may occur during the installation process, thus affecting the measurement accuracy of the sensor. However, calibrating after installation can directly perform calibration after installation, including the errors generated during the installation process in the calibration result, effectively eliminating the influence of installation factors on the measurement accuracy.

[0110] Calibrating at a fixed position on the target component helps to optimize the performance of the entire measurement system. Because the parameters obtained during calibration at this time are for a specific installation position and environment, they can better match the target component and the entire system, thereby improving the accuracy and reliability of the entire system for measuring current and providing a more accurate basis for subsequent data analysis and control.

[0111] In some examples, the current sensor provided by this solution lacks a built-in PCB. Therefore, the PCB on the target component is directly connected to the current sensor via chip pins 5 extending from the Hall effect chip 3. This direct connection reduces the number of intermediate links in the signal transmission process, shortens the signal transmission path, and thus reduces the impact of external electromagnetic interference on the signal. The signal output by the Hall effect chip 3 is typically weak and susceptible to interference. Direct connection to the PCB of the target component allows the signal to be transmitted within a relatively closed internal circuit, improving signal stability and interference resistance, and ensuring the accuracy of the measurement results.

[0112] Furthermore, direct connection reduces signal attenuation and distortion caused by factors such as connection interfaces and wires. The direct electrical connection between the Hall effect chip 3 and the PCB provides excellent conductivity and signal transmission characteristics, enabling efficient signal transmission to the processing circuitry of the target component, thereby improving the overall system's response speed and measurement accuracy.

[0113] This connection method reduces the need for additional wiring and adapters, making the circuit structure more compact. This simplified circuit structure not only reduces costs and size but also facilitates installation and maintenance, improving system reliability and maintainability. It also reduces potential points of failure and the risk of system failures caused by poor connections.

[0114] Please refer to Figure 1 In some examples, the current sensor has two detection cavities 12 , and the same copper busbar to be detected passes through the two detection cavities 12 , so that the two detection cavities 12 form a main detection cavity 12 and an auxiliary detection cavity 12 , respectively.

[0115] The redundant detection chamber 12 can perform double measurements on the same copper busbar to be detected, effectively reducing measurement errors and improving measurement accuracy and reliability; if one of the detection chambers 12 fails, the other detection chamber 12 can still work normally and continue to provide current detection data, ensuring the normal operation of the system, improving the stability and fault tolerance of the system, and improving the reliability of the current sensor.

[0116] In some examples, the primary and secondary detection chambers 12 can independently measure the current in the same copper busbar. Since the measurement results from the two detection chambers 12 should theoretically be identical, they can be calibrated by comparing the measurement data from the two detection chambers 12. If a deviation or error occurs in one detection chamber 12, comparison with the results from the other detection chamber 12 can promptly identify and correct it, thereby improving overall measurement accuracy.

[0117] When performing data output, the measurement results of the two detection cavities 12 can be averaged to reduce measurement errors. Since each detection cavity 12 may be affected by various random factors during the measurement process, such as electromagnetic interference, component noise, etc., the random errors can be offset to a certain extent through averaging operations, making the measurement results closer to the true value.

[0118] In some examples, the copper busbar to be detected may be affected by common-mode interference, such as electromagnetic field interference in the surrounding environment, power supply noise, etc. The common-mode interference will affect both the main detection cavity 12 and the auxiliary detection cavity 12. If the differential measurement method is adopted, that is, subtracting the measurement results of the two detection cavities 12, the common-mode interference signal can be effectively suppressed, and only the differential-mode signal related to the current is retained, thereby improving the measurement accuracy and anti-interference ability.

[0119] In the description of this specification, specific features, structures, materials, or characteristics can be combined in a suitable manner in any one or more embodiments or examples.

[0120] As described above, only the specific implementation manners of the present application are provided, but the protection scope of the present application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present application should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A current sensor, characterized in that, Comprising: A housing on which an installation cavity is formed. The installation cavity has an opening. A detection cavity penetrating the housing is formed inside the housing. The detection cavity is used to accommodate a copper bar to be detected. The opening direction of the detection cavity is perpendicular to the opening direction of the installation cavity; An annular iron core surrounding the detection cavity for one week and disposed inside the housing. A notch is formed on the part of the annular iron core located in the installation cavity; A Hall chip disposed in the installation cavity. The Hall chip is located at the notch. The Hall chip has chip pins. The chip pins penetrate the housing and extend outside the housing. One end of the chip pins located outside the housing is used to connect to a target PCB board; A cover plate disposed at the installation cavity. The cover plate abuts against the Hall chip. The cover plate is fixedly connected to the housing.

2. The current sensor according to claim 1, wherein A card slot is formed in the installation cavity. The Hall chip is snap-fitted in the card slot.

3. The current sensor according to claim 1, wherein The chip pins are provided in plurality. The plurality of chip pins are distributed in parallel.

4. The current sensor according to claim 3, wherein A plurality of avoidance holes are provided on the cover plate. The plurality of avoidance holes correspond to the plurality of chip pins one by one. Each chip pin passes through an independent avoidance hole.

5. The current sensor according to any one of claims 1 to 4, wherein The detection cavities are provided in two. The opening directions of the two detection cavities are the same and the two detection cavities are spaced apart. An annular iron core is provided outside each detection cavity. An installation cavity is formed at the notch of each annular iron core. The Hall chip, the cover plate and the chip pins are provided on each installation cavity.

6. The current sensor according to any one of claims 1 to 5, wherein At least two positioning posts and positioning holes are provided on the housing. The at least two positioning posts and the positioning holes are both used for positioning and installing the current sensor with the target component.

7. A manufacturing process of a current sensor, wherein The annular iron core, the embedded ring and the plastic material are integrally injection-molded to form the housing. The area where the plastic ring is located forms the positioning holes. The installation cavity and the detection cavity are formed on the housing. The card slot is formed in the installation cavity; The Hall chip is snap-fitted in the card slot. After the cover plate is buckled on the housing, the Hall chip is fixed to the housing; The avoidance holes on the cover plate are correspondingly installed with the chip pins, and the cover plate is fixed on the housing to form the current sensor according to claim 1.

8. The manufacturing process of the current sensor according to claim 7, wherein Bolt holes are provided on the housing so that the bolt holes and the embedded ring jointly form fixing holes.

9. An assembly process of a current sensor, wherein The current sensor according to any one of claims 1 to 6 is positioned by aligning the positioning holes on the current sensor with a specified area on the target component, and the current sensor and the target component are relatively fixed by a connecting member; All the protruding chip pins on the current sensor are soldered to corresponding positions on the PCB board within the target component; Calibration; The copper busbar to be detected of the target component is passed through the detection cavity of the housing of the current sensor.

10. The assembly process of the current sensor according to claim 9, wherein The current sensor has two such detection cavities, and the same copper busbar to be detected passes through the two detection cavities, so that the two detection cavities respectively form a main detection cavity and an auxiliary detection cavity.

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