Torque steering sensor

Abstract

The invention provides a torque steering sensor. The torque steering sensor comprises a shell, a first rotor, a circuit board and a second rotor, the shell is provided with a shaft hole, the first rotor is rotatably embedded in the shaft hole, the first rotor extends in the radial direction to form first blades, the first rotor is fixedly connected to an input shaft of an automobile steering device, the second rotor extends in the radial direction to form second blades, and the second rotor is fixedly connected to an output shaft of the automobile steering device. The circuit board is installed in the shell and located between the first blade and the second blade, and an eddy current detection chip used for detecting the first blade and the second blade is arranged on the circuit board so as to calculate the rotation angle difference value of the first rotor and the second rotor. And the rotation angle difference value is transmitted to an electronic control unit of the automobile steering device for torque calculation. An eddy current detection chip is adopted to collect the angle difference of the double rotors to calculate the torque, the detection precision and the anti-interference performance are improved, and stable and reliable torque signals can be provided for an EPS system.

Description

Technical Field

[0001] This invention relates to the field of automotive sensors, and more specifically to a torque steering sensor. Background Technology

[0002] Torque steering sensors are core components of automotive EPS (Electric Power Steering) systems. Their main function is to provide precise torque signals to the steering system, directly affecting the stability and safety of the vehicle's steering handling. Currently available torque steering sensors suffer from several technical shortcomings: some products use the Hall effect principle for torque detection, which not only has low measurement accuracy but also lacks robustness and is susceptible to external electromagnetic interference affecting signal accuracy; others employ complex mechanical transmission structures to ensure detection stability, resulting in a large overall size that is difficult to fit into the compact installation space of a vehicle. To meet the automotive industry's demands for high precision, miniaturization, and durability in steering sensors, there is an urgent need to develop a torque steering sensor with superior performance. Summary of the Invention

[0003] The present invention aims to at least partially solve one of the technical problems in the aforementioned technologies. Therefore, the objective of the present invention is to provide a torque steering sensor that uses an eddy current detection chip to acquire the angle difference between two rotors to calculate torque, thereby improving detection accuracy and anti-interference capabilities, and providing a stable and reliable torque signal for the EPS system.

[0004] To achieve the above objectives, the present invention provides a torque steering sensor, comprising: a housing, a first rotor, a circuit board, and a second rotor; The housing has a shaft hole, and the first rotor is rotatably fitted into the shaft hole. The first rotor has first blades arranged in a circumferential array extending radially therefrom. The first rotor is fixedly connected to the input shaft of the vehicle steering device to rotate synchronously with the input shaft. The second rotor has second blades arranged in a circumferential array extending radially therefrom. The second rotor is fixedly connected to the output shaft of the vehicle steering device to rotate synchronously with the output shaft. The circuit board is installed inside the housing and located between the first blades and the second blades. The circuit board is provided with an eddy current detection chip for detecting the first blades and the second blades to calculate the rotation angle difference between the first rotor and the second rotor, and transmits the rotation angle difference to the electronic control unit of the vehicle steering device for torque calculation.

[0005] According to the present invention, a torque steering sensor employs a dual-rotor structure with a housing shaft hole. The first rotor has a first circumferential array of blades and is rigidly connected to the input shaft, while the second rotor has a second circumferential array of blades and is rigidly connected to the output shaft. A circuit board is precisely positioned between the two sets of blades and integrates an eddy current detection chip. This chip can directly capture the position of the dual rotor blades to calculate the angle difference, and the electronic control unit then combines this with the torsion bar coefficient to calculate the torque. Compared to traditional Hall effect detection methods, this not only significantly improves detection accuracy and anti-interference capabilities but also reduces wear risk by eliminating redundant transmission components, providing a long-term stable and reliable torque signal for the EPS system.

[0006] In addition, the torque steering sensor proposed in the above embodiments of the present invention may also have the following additional technical features: Optionally, the first rotor includes an inner cylinder and an outer cylinder, the outer cylinder is rotatably fitted into the shaft hole, the first blade is disposed at the bottom of the inner cylinder, the outer cylinder is sleeved on the inner cylinder, the upper end face of the inner cylinder protrudes from the upper end face of the outer cylinder, the outer cylinder has an annular flange extending radially therefrom, and the first blade extends out from inside the annular flange.

[0007] Furthermore, the outer wall and inner wall of the housing are respectively defined by a first step groove and a second step groove. The first step groove and the second step groove are both coaxially connected with the shaft hole. The first blade and the annular convex edge are located in the second step groove. The inner cylinder is fitted with a fixing ring, which is located in the first step groove.

[0008] Furthermore, the lower end face of the fixing ring is in clearance fit with the stepped surface of the first stepped groove, the inner circumferential surface of the shaft hole is in clearance fit with the outer circumferential surface of the outer cylinder, and the upper end face of the inner cylinder is in clearance fit with the stepped surface of the first stepped groove.

[0009] Furthermore, the retaining ring is provided with teeth.

[0010] Optionally, the circuit board is provided with a connector for connecting to the electronic control unit of the vehicle steering system.

[0011] Furthermore, the housing has a cutout that exposes the connector's insertion end.

[0012] Optionally, the housing is provided with protrusions to prevent the housing from rotating. Attached Figure Description

[0013] Figure 1 An exploded view of a torque steering sensor according to an embodiment of the present invention; Figure 2This is a schematic diagram of the assembled torque steering sensor according to an embodiment of the present invention; Figure 3 for Figure 2 Partial exploded view; Figure 4 A partial exploded view of the torque steering sensor according to an embodiment of the present invention; Figure 5 This is a partial structural schematic diagram of the torque steering sensor according to an embodiment of the present invention; Figure 6 This is a partial structural diagram of the housing according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the structure of the first rotor according to an embodiment of the present invention; Figure 8 This is a schematic diagram of the installation of the torque steering sensor and the steering device mounting base according to an embodiment of the present invention; Explanation of reference numerals in the attached figures: 1. Housing, 11. Shaft hole, 12. First step groove, 13. Second step groove, 14. Hollowed-out part, 15. Protrusion, 2. First rotor, 21. First blade, 22. Inner cylinder, 23. Outer cylinder, 24. Annular protrusion, 3. Circuit board, 3. Eddy current detection chip, 31. Connector, 32. Second rotor, 41. Second blade, 41. Fixing ring, 5. Tooth, 51. Steering device mounting base, 6. Detailed Implementation

[0014] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0015] To better understand the above technical solutions, exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the invention to those skilled in the art.

[0016] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0017] The following is for reference. Figures 1-8 The implementation of the torque steering sensor proposed in the embodiments of the present invention will be described in detail.

[0018] According to an embodiment of the present invention, a torque steering sensor includes: a housing 1, a first rotor 2, a circuit board 3, and a second rotor 4; The housing 1 has a shaft hole 11, and the first rotor 2 is rotatably embedded in the shaft hole 11. The first rotor 2 has first blades 21 arranged in a circumferential array along its radial direction. The first rotor 2 is fixedly connected to the input shaft of the vehicle steering device to rotate synchronously with the input shaft. The second rotor 4 has second blades 41 arranged in a circumferential array along its radial direction. The second rotor 4 is fixedly connected to the output shaft of the vehicle steering device to rotate synchronously with the output shaft. The circuit board 3 is installed inside the housing 1 and located between the first blade 21 and the second blade 41. The circuit board 3 is provided with an eddy current detection chip 31 for detecting the first blade 21 and the second blade 41 to calculate the rotation angle difference between the first rotor 2 and the second rotor 4, and transmit the rotation angle difference to the electronic control unit of the vehicle steering device for torque calculation.

[0019] In other words, the automotive steering system includes an input shaft, an output shaft, and torsion bars located inside the input and output shafts. The two ends of the torsion bars are connected to the input and output shafts respectively. The input shaft passes through a shaft hole 11 and is rigidly connected to the first rotor 2. The second rotor 4 is rigidly connected to the output shaft outside the shaft hole. The first rotor 2 and the second rotor 4 are respectively equipped with a circumferential array of first blades 21 and second blades 41. The circuit board 3 integrating the eddy current detection chip 31 is arranged between the two sets of blades. When the driver turns the steering wheel, the torsion bar of the steering system undergoes torsional deformation, causing the input and output shafts to rotate relative to each other, thus causing the first rotor 2 and the second rotor 4 to synchronously form a corresponding angular difference. The eddy current detection chip 31 can capture the positional changes of the two sets of blades in real time, accurately calculate the rotation angle difference between the two rotors, and transmit it to the electronic control unit. The electronic control unit multiplies the rotation angle difference by the torsion bar coefficient to obtain the torque data. Compared to traditional Hall effect sensors, eddy current detection significantly improves signal anti-interference capability and detection accuracy. Furthermore, the dual-rotor direct-drive steering shaft structure eliminates redundant transmission components, reducing overall size and wear risk, and providing long-term stable and reliable torque signals for EPS systems.

[0020] The housing 1 is fixedly connected to the steering device mounting base 6. The housing 1 can be composed of an upper shell and a lower shell, which can be ultrasonically welded together. The circuit board 3 can be fixed inside the housing 1 with screws. The circuit board 3, the first rotor 2 and the second rotor 4 are all provided with through holes that are coaxial with and communicate with the shaft hole 11, so that the input shaft can pass through the housing 1, the first rotor 2 and the circuit board 3 synchronously. The second rotor 4 can be sleeved on the output shaft.

[0021] Therefore, the torque steering sensor proposed according to the present invention adopts a structure in which a dual rotor is embedded in the shaft hole 11 of the housing 1. The first rotor 2 has a first blade 21 with a circumferential array and is rigidly connected to the input shaft, and the second rotor 4 has a second blade 41 with a circumferential array and is rigidly connected to the output shaft. The circuit board 3 is precisely positioned between the two sets of blades and integrates an eddy current detection chip 31. This chip can directly capture the position of the dual rotor blades to calculate the angle difference, and the electronic control unit then combines the torsion bar coefficient to calculate the torque. Compared with the traditional Hall effect detection scheme, it not only significantly improves the detection accuracy and anti-interference ability, but also reduces the wear risk by eliminating redundant transmission components, and can provide a long-term stable and reliable torque signal for the EPS system.

[0022] Optionally, the first rotor 2 includes an inner cylinder 22 and an outer cylinder 23. The outer cylinder 23 is rotatably fitted into the shaft hole 11. The first blade 21 is located at the bottom of the inner cylinder 22. The outer cylinder 23 is fitted onto the inner cylinder 22. The upper end face of the inner cylinder 22 protrudes beyond the upper end face of the outer cylinder 23. The outer cylinder 23 has an annular flange 24 extending radially therefrom, and the first blade 21 extends from inside the annular flange 24. Understandably, this double-layer cylindrical structure of the first rotor 2 is a targeted optimization for rotor assembly and testing accuracy. The rotatable outer cylinder 23, fitted into the shaft hole 11, provides stable radial support for the first rotor 2, ensuring its coaxiality during rotation. The design of the upper end face of the inner cylinder 22 protruding beyond the outer cylinder 23 provides sufficient space for the subsequent assembly of the fixing ring 5 and also increases the contact area between the first rotor 2 and the input shaft, improving the stability of the connection between the first rotor 2 and the input shaft. The annular protrusion 24 extending from the outer cylinder 23 can provide circumferential protection for the first blade 21, preventing the blade from rubbing against the housing 1 during rotation. The first blade 21 can be integrally formed at the bottom of the inner cylinder 22. The outer cylinder 23 can be made of wear-resistant material and can partially cover the bottom of the first blade 21 and the inner cylinder 22, leaving the free end of the first blade 21 exposed.

[0023] Furthermore, the outer wall and inner wall of the housing 1 define a first stepped groove 12 and a second stepped groove 13 in a corresponding manner. The first stepped groove 12 and the second stepped groove 13 are both coaxially connected with the shaft hole 11. The first blade 21 and the annular protrusion 24 are located in the second stepped groove 13. The inner cylinder 22 is fitted with a fixing ring 5, which is located in the first stepped groove 12. Understandably, the first stepped groove 12 is located on the outer wall of the housing 1, and the second stepped groove 13 is located on the inner wall of the housing 1. The first stepped groove 12 and the second stepped groove 13 are arranged opposite to each other. During installation, the outer cylinder 23 of the first rotor 2 is inserted into the shaft hole 11 through the second stepped groove 13, so that the first blade 21 and the annular protrusion 24 are located in the second stepped groove 13, and the inner cylinder 22 extends out of the first stepped groove 12. The fixing ring 5 is sleeved on the inner cylinder 22 and abuts against the upper end face of the outer cylinder 23. In this way, the first rotor 2 is restricted to move within a certain range in the axial and radial directions. At the same time, the first blade 21 and the annular protrusion 24 being located in the second stepped groove 13 and the fixing ring 5 being located in the first stepped groove 12 can play a protective role, providing a stable and safe working space for the first rotor 2, and also greatly reducing the overall space occupied by the sensor. The diameter of the second step groove 13 is larger than the diameter of the circumference of the first blade 21, and the outer diameter of the annular convex edge 24 is smaller than the diameter of the circumference of the first blade 21. The first step groove 12 and the second step groove 13 can be integrally formed on the shell 1.

[0024] Furthermore, the lower end face of the fixing ring 5 is clearance-fitted with the stepped surface of the first stepped groove 12, the inner circumferential surface of the shaft hole 11 is clearance-fitted with the outer circumferential surface of the outer cylinder 23, and the upper end face of the inner cylinder 22 is clearance-fitted with the stepped surface of the first stepped groove 12. Understandably, the clearance fit between the lower end face of the fixing ring 5 and the stepped surface of the first stepped groove 12 avoids rotational jamming caused by excessive tightness in the fixing ring 5 assembly and also limits its axial movement; the clearance fit between the inner circumferential surface of the shaft hole 11 and the outer circumferential surface of the outer cylinder 23 controls the radial runout amplitude of the first rotor 2; and the clearance fit between the upper end face of the inner cylinder 22 and the stepped surface of the first stepped groove 12 further enhances the axial limiting effect. Precise control of each fitting clearance can significantly reduce the wear rate between components, avoid a decrease in detection accuracy caused by increased clearance after long-term operation, effectively extend the sensor's entire lifespan, and ensure continuous and reliable torque signal output.

[0025] Furthermore, the fixing ring 5 is provided with teeth 51. Understandably, these teeth 51 can directly serve as the rotation angle output end of the input shaft. For applications requiring separate acquisition of the input shaft rotation angle, external detection components can directly obtain the input shaft rotation angle data through meshing with or signal coupling with these teeth 51, without the need for additional signal output structures. That is, the fixing ring 5 not only serves to fix the first rotor 2 but also functions as the output end of the steering input shaft. The teeth 51 can be integrally formed on the fixing ring 5, and the teeth 51 can be ring gears, the diameter of which can be smaller than the diameter of the fixing ring 5.

[0026] Optionally, the circuit board 3 is equipped with a connector 32 for connecting to the electronic control unit of the vehicle's steering system. Understandably, the connector 32 integrated on the circuit board 3 is the core component for establishing signal interaction between the sensor and the electronic control unit of the vehicle's steering system. It achieves a stable electrical connection with the circuit board 3 via pins, forming an integrated signal transmission module. The interface specifications of this connector 32 are compatible with the communication protocols of mainstream automotive steering system electronic control units, enabling the accurate transmission of the rotor angle difference signal calculated by the eddy current detection chip 31 on the circuit board 3 to the electronic control unit in the form of an electrical signal, providing a reliable data link for subsequent torque conversion. Simultaneously, the integrated design of the connector 32 and the circuit board 3 eliminates the cumbersome process of additional wiring, reducing the space occupied inside the sensor, improving the overall structural compactness, reducing interference and loss during signal transmission, ensuring the real-time performance and accuracy of torque data, and enhancing the compatibility of the sensor with the vehicle's EPS system.

[0027] Furthermore, the housing 1 exposes a cutout 14 at the connector 32's insertion end. Understandably, the position and size of the cutout 14 match the connector 32's insertion end, facilitating connection between the connector 32 and the wiring harness of the automotive steering electronic control unit without disassembling the sensor housing 1, simplifying vehicle assembly and subsequent maintenance. It also provides some limiting protection for the connector 32, reducing bending or damage to the insertion end due to external impacts. Simultaneously, the cutout structure provides adequate heat dissipation space, preventing the connector 32 from overheating during long-term operation and affecting signal transmission stability, thus ensuring efficient torque data transmission.

[0028] Optionally, the housing 1 is provided with a protrusion 15 to prevent rotation of the housing 1. Understandably, this protrusion 15 can be precisely inserted into the corresponding slot of the steering device mounting seat 6, effectively limiting the circumferential rotation of the sensor housing 1. This prevents the relative position of the circuit board 3 and the dual rotor from shifting due to the sensor's own rotation during vehicle steering, thus preventing changes in the detection reference of the eddy current detection chip 31. Furthermore, the anti-rotation protrusion 15 can also share some of the radial impact force on the sensor, reducing the vibration amplitude of the internal components of the housing 1, providing a stable working environment for the circuit board 3 and the dual rotor, and ensuring the continuity and accuracy of torque signal acquisition and transmission. The protrusion 15 can be equipped with a flexible snap-fit ​​for easy quick assembly and disassembly from the steering device mounting seat 6; there can be two protrusions 15.

[0029] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0030] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0031] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0032] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0033] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. The illustrative expressions of the above terms in this specification should not be construed as necessarily referring to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0034] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A torque turning sensor characterized by, The utility model relates to a kind of automobile steering device, including: Shell, first rotor, circuit board and second rotor; The shell is equipped with shaft hole, the first rotor is rotatably embedded in the shaft hole, the first rotor extends in its radial direction with the first blade of circumferential array, the first rotor is fixedly connected on the input shaft of automobile steering device to follow the input shaft synchronous rotation, the second rotor extends in its radial direction with the second blade of circumferential array, the second rotor is fixedly connected on the output shaft of automobile steering device to follow the output shaft synchronous rotation, the circuit board is installed in the shell and is located between the first blade and the second blade, the circuit board is equipped with eddy current detection chip for detecting the first blade and the second blade, to calculate the rotation angle difference of the first rotor and the second rotor, and the rotation angle difference is transmitted to the electronic control unit of automobile steering device to calculate torque.

2. The torque turn sensor of claim 1, wherein, The first rotor includes inner cylinder and outer cylinder, the outer cylinder is rotatably embedded in the shaft hole, the first blade is arranged at the bottom of the inner cylinder, the outer cylinder is sleeved on the inner cylinder, the upper end surface of the inner cylinder protrudes the upper end surface of the outer cylinder, the outer cylinder extends in its radial direction with annular flange, and the first blade extends from the inside of the annular flange.

3. The torque turn sensor of claim 2, wherein, The outer wall and the inner wall of the shell correspondingly define the first step groove and the second step groove, the first step groove and the second step groove are coaxially communicated with the shaft hole, the first blade and the annular flange are located in the second step groove, the inner cylinder is sleeved with fixing ring, and the fixing ring is located in the first step groove.

4. The torque sensing of claim 3 wherein, The lower end surface of the fixing ring is in clearance fit with the step surface of the first step groove, the inner periphery of the shaft hole is in clearance fit with the outer periphery of the outer cylinder, and the upper end surface of the inner cylinder is in clearance fit with the step surface of the first step groove.

5. The torque sensing of claim 3 wherein, The fixing ring is provided with a tooth portion.

6. The torque sensing of claim 1 wherein, The circuit board is provided with a connector for connecting with the electronic control unit of the automobile steering device.

7. The torque sensing of claim 6 wherein, The shell is provided with a hollow portion exposing the plug-in end of the connector.

8. The torque sensing of claim 1 wherein, The shell is provided with a protrusion for preventing the shell from rotating.

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