Highly Integrated Multi-Unit Current Sensor for New Energy Vehicles and Its Assembly Process

Abstract

The present invention provides a highly integrated multi-unit current sensor for new energy vehicles and an assembly process, belonging to the technical field of sensors, including: a housing, on which there are pins, inserts and a receiving cavity. One end of the pin is located outside the housing, and the other end of the pin extends into the receiving cavity. The insert includes an iron core, which is formed by stacking and stamping and riveting multiple magnetic sheets; a printed circuit board assembly, which is embedded in the receiving cavity and is electrically connected and matched with the end of the pin extending into the receiving cavity; a housing cover, which is detachably connected to the housing and is used to seal the receiving cavity after connecting the printed circuit board assembly. By changing the structure of the iron core to be formed by stacking and stamping and riveting multiple magnetic sheets, the present invention achieves a current sensor with controllable external dimensions, good consistency, and a high qualified rate in mass production.

Description

Technical Field

[0001] The present invention belongs to the technical field of sensors, and relates to a current sensor, in particular to a highly integrated multi-unit current sensor for new energy vehicles and an assembly process thereof. Background Art

[0002] With the continuous development of technologies such as electronic power, computer technology, and ASIC, the traditional Hall technology has been difficult to meet the requirements of the motor control system of new energy vehicles. Sensor integration, miniaturization, low power consumption, large measurement range, etc. are the only way for future motor controller systems.

[0003] The existing current sensor assembly processes are generally divided into two types. The first type is an integrated current sensor for detecting the phase current of an automotive electronic control system disclosed in Chinese Patent (201720563932.6). It first assembles the housing, iron core, Hall element, and printed circuit board, and makes a preliminary positioning through the limiting structure on the housing, and finally fixes it with potting glue. The second type is a multi-channel current sensor for new energy vehicles disclosed in Chinese Patent (201921931534.0). After integrally injection molding the iron core, housing, and pins, it is welded to the printed circuit board and finally assembled with the housing cover.

[0004] However, whether the first method or the second method is adopted, the iron core is a wound iron core, that is, a coil is wound along the contour of the magnet on the surface of the magnet to form an iron core. For such an iron core structure, the external dimensions of the iron core are uncontrollable and the consistency is poor. Summary of the Invention

[0005] The object of the present invention is to address the above problems existing in the prior art, and propose a current sensor with controllable external dimensions, good consistency, and a high qualified rate for mass production.

[0006] The object of the present invention can be achieved by the following technical solutions: A highly integrated multi-unit current sensor for new energy vehicles, comprising:

[0007] A housing integrally injection molded, with pins, inserts, and a receiving cavity provided on the housing. One end of the pin is located outside the housing, and the other end of the pin extends into the receiving cavity. The insert horizontally penetrates the entire housing, and the length direction of the insert is perpendicular to the opening direction of the receiving cavity. One end of the pin protruding from the housing and the insert are respectively located on the upper and lower sides of the receiving cavity. The length direction of the receiving cavity is the same as the length direction of the housing. The insert includes an iron core, and the iron core is formed by stacking and stamping and riveting multiple magnetic sheets;

[0008] A printed circuit board assembly, embedded in the receiving cavity and electrically connected and cooperating with one end of the pin extending into the receiving cavity;

[0009] The cover is detachably connected to the housing and is used to seal the accommodation cavity after connecting the printed circuit board assembly.

[0010] In the above-mentioned highly integrated multi-unit current sensor for new energy vehicles, a through groove is provided on the iron core in the thickness direction of the iron core, and a boss is provided on the bottom of the through groove. The two sides of the boss are smoothly transitioned to the bottom of the through groove through inclined surfaces. Among them, the through groove is arranged in a T shape. The through groove includes a horizontal channel and a vertical channel, and the boss is arranged on the horizontal channel. A stepped portion is provided at each end of the horizontal channel. When the insert is injection-molded, the boss and the two stepped portions serve as the positioning positions of the iron core.

[0011] In the above-mentioned highly integrated multi-unit current sensor for new energy vehicles, the insert further includes a bus bar, and the bus bar is connected to the iron core by injection molding. Among them, in the insert after injection molding, the bus bar is inserted into the plastic filled in the through groove of the iron core, and the length direction of the bus bar is perpendicular to the opening direction of the iron core. When the bus bar is connected to the client, it is connected by bolt fastening or by laser welding.

[0012] In the above-mentioned highly integrated multi-unit current sensor for new energy vehicles, one end of the bus bar connected to the client is bent, so that there is a height difference in the horizontal direction between the two ends of the bus bar.

[0013] In the above-mentioned highly integrated multi-unit current sensor for new energy vehicles, both sides of the bus bar are provided with a serrated structure.

[0014] In the above-mentioned highly integrated multi-unit current sensor for new energy vehicles, one end of the pin is a first plug end in the shape of a fisheye. This first plug end is the end where the sensor is connected to an external device. The other end of the pin is a second plug end connected to the printed circuit board assembly. Among them, the extension direction of the first plug end is perpendicular to the extension direction of the second plug end.

[0015] In the above-mentioned highly integrated multi-unit current sensor for new energy vehicles, a convex block integrally provided with the pin is provided at the corner of the pin, so that the corner of the pin is provided with a stepped shape.

[0016] In the above-mentioned highly integrated multi-unit current sensor for new energy vehicles, a convex portion is provided at a position on the housing corresponding to the pin.

[0017] The present invention also provides an assembly process for a highly integrated multi-unit current sensor for new energy vehicles, including the steps:

[0018] S1: Pre-completing the injection molding between the bus bar and the iron core to form an insert;

[0019] S2: Injecting and molding the insert in step S1 and the pin to form an integrally injection-molded housing;

[0020] S3: Install the printed circuit board assembly into the housing in step S2, and complete the welding electrical connection between the printed circuit board assembly and the pins.

[0021] S4: Complete the connection between the cover and the housing in step S3 to achieve the sealing of the printed circuit board assembly.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0023] (1) The iron core is formed by stacking and stamping multiple sub-magnetic sheets and riveting them together. Therefore, the processed iron core has high precision control of its external dimensions, good consistency, can achieve batch production, and has a relatively high qualification rate. Moreover, by adjusting the shape of each magnetic sheet and the number of stacked layers, the overall magnetization effect of the iron core is optimized, and the cross-sectional area at different positions of the magnetic circuit is controlled to achieve the best magnetic concentration effect within the same boundary. In addition, when multiple magnetic sheets are riveted and fixed, the riveting positions can be arranged along the direction of the magnetic circuit, thereby reducing the influence of riveting stress on the magnetization performance of the iron core.

[0024] (2) The housing is injection-molded without the need for potting encapsulation, so that there is no need to have a gap in the internal space of the entire housing, thereby realizing the integration and miniaturization of the sensor.

[0025] (3) The iron core and the housing are injection-molded together. Through the boss on the iron core and the stepped parts on both sides, the stability of the iron core air gap opening size can be ensured without the need to use a fixing piece to maintain the stability of the iron core air gap opening size. Moreover, since the iron core and the housing are injection-molded together, the plastic parts are filled in the through groove of the iron core, thereby improving the insulation effect of the iron core and eliminating the need to consider the grounding problem of the iron core.

[0026] (4) Since the busbar and the iron core are injection-molded together, and the insert and the housing are also injection-molded together, customers can freely choose whether the insert contains the busbar component, improving the flexibility of sensor molding. In addition, by integrating the busbar, the performance of the sensor is further enhanced. Moreover, as the connection component with the client, when threaded holes or through holes are provided on the busbar, a firm connection between the busbar and the client can be achieved. When no threaded holes or through holes are provided on the busbar, laser welding between the busbar and the client can be realized, thereby improving the connection flexibility between the busbar and the client.

[0027] (5) By bending one end of the busbar connected to the client, the mechanical stress caused by bolt fastening or laser welding when the busbar is connected to the client can be effectively reduced, thereby improving the reliability of sensor use and extending the service life of the sensor.

[0028] (6) Since the bus bar is connected to the iron core by injection molding, and the bus bar is connected to the plastic at the filling position of the through groove on the iron core, by setting serrated structures on both sides of the bus bar, the bonding force between the bus bar and the plastic after overall injection molding can be effectively increased, avoiding mutual slippage between the plastic and the bus bar, thereby improving the reliability of the entire insert structure.

[0029] (7) One end of the pin connected to the external device is set in a fisheye shape, which can avoid connecting the pin to the external device by welding. Thus, the risks of false soldering and missed soldering are avoided, and the assembly efficiency is high, which is more suitable for mass production. Moreover, the middle part of the first plug end in the fisheye shape is hollow, making the first plug end elastic and further improving the reliability when the pin is connected to the external device.

[0030] (8) By setting bumps at the corners of the pin, the overall strength of the pin is improved, thus avoiding deformation when the first plug end is connected to the external device, thereby improving the reliability when the pin is connected to the external device.

[0031] (9) By setting convex parts, the strength at the position of the pin on the housing is increased, thus avoiding the corresponding deformation risk when the first plug end is connected to the external device, and further extending the service life of the sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 FIG. is an exploded view of a highly integrated multi-unit current sensor for a new energy vehicle according to the present invention.

[0033] Figure 2 FIG. is a schematic structural diagram of a housing in a preferred embodiment of the present invention.

[0034] Figure 3 FIG. is an exploded view of a housing in a preferred embodiment of the present invention.

[0035] Figure 4 FIG. is a schematic structural diagram of an insert in a preferred embodiment of the present invention.

[0036] Figure 5 FIG. is a schematic structural diagram of an iron core in a preferred embodiment of the present invention.

[0037] Figure 6 FIG. is a cross-sectional view of an iron core in a preferred embodiment of the present invention.

[0038] Figure 7 FIG. is a schematic structural diagram of a pin in a preferred embodiment of the present invention.

[0039] In the figure, 100 is the housing; 110 is the pin; 111 is the first plug-in end; 112 is the second plug-in end; 113 is the bump; 120 is the insert; 121 is the iron core; 1211 is the through groove; 1212 is the boss; 1213 is the stepped portion; 122 is the plastic; 123 is the busbar; 130 is the receiving cavity; 131 is the convex portion; 200 is the printed circuit board assembly; 300 is the housing cover. Detailed implementation manners

[0040] The following are specific embodiments of the present invention and, in combination with the accompanying drawings, further describe the technical solutions of the present invention, but the present invention is not limited to these embodiments.

[0041] It should be noted that all 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.

[0042] As Figures 1 to 7 shown, a highly integrated multi-unit current sensor for a new energy vehicle provided by the present invention includes:

[0043] A housing 100 integrally injection-molded, and a pin 110, an insert 120 and a receiving cavity 130 are provided on the housing 100. One end of the pin 110 is located outside the housing 100, and the other end of the pin 110 extends into the receiving cavity 130. The insert 120 horizontally penetrates the entire housing 100, and the length direction of the insert 120 is perpendicular to the opening direction of the receiving cavity 130. One end of the pin 110 extending out of the housing 100 and the insert 120 are respectively located on the upper and lower sides of the receiving cavity 130. The length direction of the receiving cavity 130 is consistent with the length direction of the housing 100. The insert 120 includes an iron core 121, and the iron core 121 is formed by stacking, stamping and riveting multiple magnetic sheets;

[0044] A printed circuit board assembly 200, which is embedded in the receiving cavity 130 and is electrically connected and cooperated with one end of the pin 110 extending into the receiving cavity 130;

[0045] A housing cover 300, which is detachably connected to the housing 100 and is used to seal the receiving cavity 130 after connecting the printed circuit board assembly 200.

[0046] It is worth mentioning that the iron core 121 in this embodiment is formed by stacking, stamping and riveting multiple sub-magnetic sheets. Therefore, the processed iron core 121 has high control precision of the external dimension, good consistency, can achieve mass production, and has a high qualification rate. Moreover, by adjusting the shape of each magnetic sheet and the number of stacked layers, the overall magnetization effect of the iron core 121 is optimized, and the cross-sectional area at different positions of the magnetic circuit is controlled to achieve the best magnetic concentration effect within the same boundary. In addition, when the multiple magnetic sheets are riveted and fixed, the riveting positions can be arranged along the direction of the magnetic circuit, so as to reduce the influence of the riveting stress on the magnetization performance of the iron core 121.

[0047] In addition, in this embodiment, the housing 100 is injection molded without potting encapsulation, so that there is no need to have a gap in the internal space of the entire housing 100, thereby realizing the integration and miniaturization of the sensor.

[0048] A highly integrated multi-unit current sensor for a new energy vehicle provided by the present invention achieves a current sensor with controllable external dimensions, good consistency, and high batch production qualification rate by changing the structure of the iron core 121 to be formed by stacking, stamping and riveting multiple magnetic sheets.

[0049] Preferably, a through groove 1211 penetrating the thickness direction of the iron core 121 is provided on the iron core 121, and a boss 1212 is provided on the bottom of the through groove 1211. The two sides of the boss 1212 are smoothly transitioned to the bottom of the through groove 1211 through inclined surfaces. Among them, the through groove 1211 is arranged in a T shape. The through groove 1211 includes a horizontal channel and a vertical channel, and the boss 1212 is provided on the horizontal channel. A stepped portion 1213 is provided at each end of the horizontal channel. When the insert 120 is injection molded, the boss 1212 and the two stepped portions 1213 serve as the positioning positions of the iron core 121.

[0050] It is worth mentioning that the contour of the iron core 121 in this embodiment is roughly the same as that of the iron core 121 in the prior art, and is arranged in a C-shaped structure. The opening of the C-shaped iron core 121 serves as the air gap opening of the iron core 121. In the prior art, in order to ensure the stability of the size of the air gap opening of the iron core 121, a fixing piece needs to be connected at the air gap opening, and a grounding end is provided on the fixing piece. In this embodiment, however, the iron core 121 and the housing 100 are injection-molded, and through the boss 1212 on the iron core 121 and the stepped portions 1213 on both sides, the stability of the size of the air gap opening of the iron core 121 can be ensured, without the need to use a fixing piece to maintain the stability of the size of the air gap opening of the iron core 121. Moreover, since the iron core 121 and the housing 100 are injection-molded, the plastic 122 is filled in the through groove 1211 of the iron core 121, thereby improving the insulation effect of the iron core 121 and eliminating the need to consider the grounding problem of the iron core 121. Therefore, compared with the structure of the iron core 121 in the prior art, the iron core 121 in this embodiment omits the structure for maintaining the stability of the size of the air gap opening of the iron core 121 and the grounding problem, thus simplifying the assembly process of the sensor.

[0051] In addition, the iron core 121 in this embodiment is formed by stacking and stamping and riveting multiple magnetic sheets, and the riveting positions are located at the respective corners of the iron core 121. The extension lines of adjacent two riveting positions intersect to form a "diamond" structure, thereby reducing the influence of the riveting stress on the magnetization performance of the iron core 121.

[0052] Preferably, the insert 120 further includes a bus bar 123, and the bus bar 123 is connected to the iron core 121 by injection molding. Among them, in the insert 120 after injection molding, the bus bar 123 is inserted into the plastic 122 filled in the through groove 1211 of the iron core 121, and the length direction of the bus bar 123 is perpendicular to the opening direction of the iron core 121.

[0053] In this embodiment, since the bus bar 123 and the iron core 121 are injection-molded, and the insert 120 and the housing 100 are also injection-molded, customers can freely choose whether the insert 120 includes the component of the bus bar 123, thereby improving the flexibility of sensor molding. In addition, by integrating the bus bar 123, the performance of the sensor is further enhanced. Moreover, the bus bar 123 serves as a connecting component to the client. When threaded holes or through holes are provided on the bus bar 123, a firm connection between the bus bar 123 and the client can be achieved. When no threaded holes or through holes are provided on the bus bar 123, laser welding between the bus bar 123 and the client can be achieved, thereby improving the flexibility of the connection between the bus bar 123 and the client.

[0054] Further preferably, one end of the bus bar 123 connected to the client is bent, such that there is a height difference in the horizontal direction between the two ends of the bus bar 123.

[0055] In this embodiment, by bending one end of the busbar 123 connected to the client, the mechanical stress caused by bolt fastening or laser welding when the busbar 123 is connected to the client can be effectively reduced, thereby improving the reliability of the sensor and extending the service life of the sensor.

[0056] Further preferably, both sides of the busbar 123 are provided with a serrated structure.

[0057] In this embodiment, since the busbar 123 and the iron core 121 are connected by injection molding, and the busbar 123 is connected to the plastic 122 at the filling position of the through groove 1211 on the iron core 121, by providing a serrated structure on both sides of the busbar 123, the bonding force between the busbar 123 and the plastic 122 after overall injection molding can be effectively increased, avoiding mutual slippage between the plastic 122 and the busbar 123, thereby improving the reliability of the entire insert 120 structure.

[0058] Preferably, the pin 110 is generally arranged in a Z-shaped structure, and one end of the pin 110 is a first plug end 111 in the shape of a fish eye. This first plug end 111 is the end where the sensor is connected to an external device. The other end of the pin 110 is a second plug end 112 connected to the printed circuit board assembly 200. Among them, the extending direction of the first plug end 111 is perpendicular to the extending direction of the second plug end 112.

[0059] In this embodiment, by setting the end of the pin 110 connected to the external device in the shape of a fish eye, the connection method of welding when the pin 110 is connected to the external device can be avoided, thereby avoiding the risks of false soldering and missed soldering, and having high assembly efficiency, being more suitable for mass production. Moreover, the middle part of the first plug end 111 in the shape of a fish eye is hollow, making the first plug end 111 elastic and capable of further improving the reliability when the pin 110 is connected to the external device.

[0060] Further preferably, a convex block 113 integrally provided with the pin 110 is provided at the corner of the pin 110, so that the corner of the pin 110 is provided in a stepped shape.

[0061] In this embodiment, by providing the convex block 113 at the corner of the pin 110, the overall strength of the pin 110 is improved, thereby avoiding deformation when the first plug end 111 is connected to the external device, and thus improving the reliability when the pin 110 is connected to the external device.

[0062] Further preferably, a convex portion 131 is provided at a position on the housing 100 corresponding to the pin 110.

[0063] In this embodiment, by providing the convex portion 131, the strength of the position of the pin 110 on the housing 100 is increased, thereby avoiding the corresponding deformation risk when the first plug end 111 is connected to an external device, and further extending the service life of the sensor.

[0064] The present invention also provides an assembly process for a highly integrated multi-unit current sensor for a new energy vehicle, including the steps of:

[0065] S1: Pre-completing the injection molding between the bus bar 123 and the iron core 121 to form the insert 120;

[0066] S2: Completing the injection molding of the insert 120 in step S1 and the pin 110 to form the integrally injection-molded housing 100;

[0067] S3: Embedding the printed circuit board assembly 200 in the housing 100 in step S2 and completing the welding electrical connection between the printed circuit board assembly 200 and the pin 110;

[0068] S4: Completing the connection of the cover to the housing 100 in step S3 to achieve the sealing of the printed circuit board assembly 200.

[0069] It should be noted that in the present invention, descriptions such as "first", "second", "one", etc. are only for descriptive purposes and should not be construed as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically defined. Terms such as "connection" and "fixation" should be understood in a broad sense. For example, "fixation" may be a fixed connection, a detachable connection, or an integral body; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two components or the interaction relationship between two components, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0070] In addition, the technical solutions between various embodiments of the present invention can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement it. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present invention.

[0071] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Those skilled in the art to which the present invention pertains may make various modifications or supplements to the described specific embodiments or use similar means for substitution, but will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

Claims

1. A highly integrated multi-unit current sensor for new energy vehicles, characterized in that, Comprising: A housing integrally injection-molded, with pins, inserts and a receiving cavity provided on the housing. One end of the pin is located outside the housing, and the other end of the pin extends into the receiving cavity. The insert horizontally penetrates the entire housing, and the length direction of the insert is perpendicular to the opening direction of the receiving cavity. The end of the pin protruding from the housing and the insert are respectively located on the upper and lower sides of the receiving cavity. The length direction of the receiving cavity is consistent with the length direction of the housing. Wherein, the insert includes an iron core, and the iron core is formed by stacking, stamping and riveting multiple magnetic sheets; A printed circuit board assembly, embedded in the receiving cavity and electrically connected and cooperated with the end of the pin extending into the receiving cavity; A cover, detachably connected to the housing and used to seal the receiving cavity after connecting the printed circuit board assembly; A through groove penetrating the thickness direction of the iron core is provided on the iron core, and a boss is provided on the bottom of the through groove. The two sides of the boss are smoothly transitioned to the bottom of the through groove through inclined surfaces. Wherein, the through groove is arranged in a T shape. The through groove includes a horizontal channel and a vertical channel, and the boss is arranged on the horizontal channel. A stepped portion is provided at each end of the horizontal channel. When the insert is injection-molded, the boss and the two stepped portions serve as the positioning positions of the iron core.

2. The highly integrated multi-unit current sensor for new energy vehicles according to claim 1, wherein The insert further includes a busbar, and the busbar is connected to the iron core by injection molding. Wherein, in the insert after injection molding, the busbar is inserted into the plastic filled in the through groove of the iron core, and the length direction of the busbar is perpendicular to the opening direction of the iron core. When the busbar is connected to the client, it is fixedly connected by bolts or laser welded.

3. The highly integrated multi-unit current sensor for new energy vehicles according to claim 2, characterized in that, One end of the busbar connected to the client is bent, so that there is a height difference in the horizontal direction between the two ends of the busbar.

4. The highly integrated multi-unit current sensor for new energy vehicles according to claim 2, characterized in that, Both sides of the busbar are provided with a serrated structure.

5. The highly integrated multi-unit current sensor for new energy vehicles according to claim 1, characterized in that, One end of the pin is a first plug end in the shape of a fish eye, and this first plug end is the end where the sensor is connected to an external device. The other end of the pin is a second plug end connected to the printed circuit board assembly. Wherein, the extending direction of the first plug end is perpendicular to the extending direction of the second plug end.

6. The highly integrated multi-body current sensor for new energy vehicles according to claim 1, wherein, A convex block integrally provided with the pin is provided at the corner of the pin, so that the corner of the pin is provided with a stepped shape.

7. The highly integrated multi-link current sensor for new energy vehicles according to claim 1, wherein A convex portion is provided at a position on the housing corresponding to the pin.

8. An assembly process for a highly integrated multi-unit current sensor for new energy vehicles according to any one of claims 1 to 7, characterized in that, Including steps: S1: Pre-completing the injection molding between the busbar and the iron core to form an insert; S2: Injecting and molding the insert in step S1 and the pin to form an integrally injection-molded housing; S3: Embedding the printed circuit board assembly in the housing in step S2 and completing the welding and electrical connection between the printed circuit board assembly and the pin; S4: Completing the connection between the cover and the housing in step S3 to realize the sealing of the printed circuit board assembly.

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