wheel speed sensor

Abstract

This application discloses a wheel speed sensor, which includes an inner frame, an outer frame, a circuit board, a magnet, a first chip, and a second chip. A mounting cavity is formed inside the outer frame, and the inner frame is disposed within the mounting cavity. The first chip and the second chip are disposed at one end of the inner frame. The magnet is disposed on the inner frame, and the magnet, the first chip, and the second chip are directly opposite each other along the axial direction of the inner frame. The circuit board is disposed on the inner frame, and both the first chip and the second chip are electrically connected to the circuit board. This application employs dual-chip detection, which can improve the reliability and stability of wheel speed detection. By using a circuit board for circuit design of the dual-chip wheel speed sensor, related signal stability circuit design can be performed from the sensor source, avoiding the influence of long-distance parasitic capacitance and inductance, reducing high-frequency noise interference, and further improving the reliability and stability of wheel speed detection.

Description

Technical Field

[0001] This application relates to the field of wheel speed sensor technology, and in particular to a wheel speed sensor. Background Technology

[0002] Most existing wheel speed sensors are single-chip sensors, lacking signal backup. When the single chip fails, the signal fails, leading to abnormal vehicle control. Some related technologies employ dual chips for redundancy, but these lack internal hardware circuitry, resulting in poor signal stability and reliance on the vehicle's braking system's main controller for signal stabilization. Furthermore, the presence of two chips makes these dual-chip sensors unsuitable for different gear angles. Moreover, existing wheel speed sensors typically involve injection molding the inner frame first, followed by injection molding the outer frame around it, preventing separate injection molding and resulting in low overall production efficiency. Summary of the Invention

[0003] This application aims to address at least one of the technical problems existing in the prior art. To this end, one objective of this application is to propose a wheel speed sensor that solves the problems of poor structural adaptability and insufficient signal stability in existing wheel speed sensors.

[0004] This application proposes a wheel speed sensor, which includes an inner frame, an outer frame, a circuit board, a magnet, a first chip, and a second chip. The outer frame has a mounting cavity, and the inner frame is disposed within the mounting cavity. The first chip and the second chip are disposed at one end of the inner frame. The magnet is disposed on the inner frame, and the magnet, the first chip, and the second chip are disposed opposite each other along the axial direction of the inner frame. The circuit board is disposed on the inner frame, and both the first chip and the second chip are electrically connected to the circuit board.

[0005] According to some embodiments of this application, a first mating portion is formed at the other end of the inner frame, and a second mating portion is formed on the outer frame. The first mating portion and the second mating portion are mated and connected to each other to facilitate circumferential positioning of the inner frame and the outer frame.

[0006] According to some embodiments of this application, the first mating part and / or the second mating part are configured as a plurality of parts spaced apart along the circumferential direction, and any first mating part is adapted to mate and connect with any second mating part.

[0007] According to some embodiments of this application, a first mounting groove is formed at one end of the inner skeleton, and a first chip and a second chip are disposed in the first mounting groove at intervals along a first direction; the circuit board has interfaces formed on both sides of the first direction, and the two interfaces are adapted to be connected to the first chip and the second chip respectively through connecting lines.

[0008] According to some embodiments of this application, a clearance channel suitable for the passage of connecting lines is formed between the inner frame and the outer frame, and the clearance channel is connected to the first mounting groove.

[0009] According to some embodiments of this application, the inner frame is formed with a second mounting groove, and the circuit board is disposed in the second mounting groove; the circuit board is formed with at least one positioning hole, and at least one positioning post that mates with and connects to the positioning hole is formed in the second mounting groove.

[0010] According to some embodiments of this application, the circuit board includes a circuit board body and a protection circuit, a processing unit, a voltage regulator circuit, and a filter circuit disposed on the circuit board body. One end of the protection circuit is electrically connected to a power input node. The processing unit is communicatively connected to a first chip and a second chip to receive and process detection signals generated by the first and second chips. The power input terminal of the processing unit is electrically connected to the other end of the protection circuit, and the ground terminal of the processing unit is electrically connected to a ground node. The processing unit has a first output terminal and a second output terminal to output a processed output signal. The voltage regulator circuit is connected to the other end of the protection circuit and the ground node to stabilize the voltage of the processing unit. The filter circuit is connected to the ground node and the processing unit to filter out high-frequency noise signals in the output signal.

[0011] According to some embodiments of this application, the protection circuit includes a first diode and a resistor. The anode of the first diode is electrically connected to a power supply access node; one end of the resistor is electrically connected to the cathode of the first diode, and the other end of the resistor is connected to the power input terminal of the processing unit.

[0012] According to some embodiments of this application, the voltage regulator circuit includes a first capacitor and a second diode. One end of the first capacitor is electrically connected to the other end of a resistor, and the other end of the first capacitor is electrically connected to a ground node. The cathode of the second diode is electrically connected to the connection node between the first capacitor and the resistor, and the anode of the second diode is electrically connected to the ground node.

[0013] According to some embodiments of this application, the filter circuit includes a second capacitor and a third capacitor. One end of the second capacitor is electrically connected to a second output terminal, and the other end of the second capacitor is electrically connected to a ground node. One end of the third capacitor is electrically connected to a first output terminal, and the other end of the third capacitor is electrically connected to a ground node.

[0014] This application employs dual-chip detection, which improves the reliability and stability of wheel speed detection. By utilizing a circuit board to design internal stability circuits for the dual-chip wheel speed sensor, signal stability circuit design can be implemented from the sensor source, avoiding the influence of long-distance parasitic capacitance and inductance, reducing high-frequency noise interference, and further improving the reliability and stability of wheel speed detection. Furthermore, the independent outer and inner frame structures of this application allow for separate assembly, improving production efficiency.

[0015] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0016] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0017] Figure 1 This is a first axial cross-sectional view of a wheel speed sensor according to some embodiments of this application; Figure 2 This is a second axial sectional view of a wheel speed sensor according to some embodiments of this application; Figure 3 This is a first-view structural schematic diagram of a wheel speed sensor (without the exoskeleton) according to some embodiments of this application; Figure 4 This is a structural schematic diagram of a wheel speed sensor (without the exoskeleton) according to some embodiments of this application from a second perspective. Figure 5 This is a schematic diagram of the structure of a wheel speed sensor according to some embodiments of this application; Figure 6 This is a schematic diagram of the exoskeleton according to some embodiments of this application; Figure 7 This is a circuit diagram of a circuit board according to some embodiments of this application; Figure 8 This is a spectrum diagram of the detection signal from the wheel speed sensor before processing; Figure 9 This is a spectrum diagram of the detection signal (output signal) of a wheel speed sensor according to some embodiments of this application; Figure 10 This is a schematic diagram of the pulse signal of a wheel speed sensor according to some embodiments of this application.

[0018] Figure label: Inner frame 10; First mating part 11; First mounting groove 12; Second mounting groove 13; Third mounting groove 14; Clearance hole 15; Positioning post 16; Outer frame 20; Second mating part 21; Connecting part 22; Circuit board 30; First interface 31; Second interface 32; Magnet 40; First chip 50; Second chip 60; First connecting line 71; Second connecting line 72; Cover plate 80; First clearance channel 91; Second clearance channel 92. Detailed Implementation

[0019] The embodiments of this application are described in detail below. Examples of these embodiments are shown 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 are only used to explain this application, and should not be construed as limiting this application.

[0020] The following is for reference. Figures 1-10 A wheel speed sensor according to an embodiment of this application is described.

[0021] This application proposes a wheel speed sensor, which includes an inner frame 10, an outer frame 20, a circuit board 30, a magnet 40, a first chip 50, and a second chip 60. The outer frame 20 has a mounting cavity, and the inner frame 10 is disposed in the mounting cavity. The first chip 50 and the second chip 60 are disposed at one end of the inner frame 10. The magnet 40 is disposed on the inner frame 10, and the magnet 40, the first chip 50, and the second chip 60 are directly opposite each other along the axial direction of the inner frame 10. The circuit board 30 is disposed on the inner frame 10, and the first chip 50 and the second chip 60 are both electrically connected to the circuit board 30.

[0022] According to the wheel speed sensor of this application, based on the Hall effect principle, a magnet 40 provides a magnetic field, and a first chip 50 and a second chip 60 are disposed in the magnetic field. When the wheel rotates, the change in magnetic reluctance on the gear ring causes a change in the magnetic field strength. When the first chip 50 and the second chip 60 sense the change in the magnetic field, they generate pulse signals and transmit them to the circuit board 30. After processing and calculation, the wheel rotation speed can be obtained from the pulse signals, thereby realizing wheel speed detection. The circuit board 30 allows for circuit design to process the signal. The use of the first chip 50 and the second chip 60 provides redundant detection, avoiding the failure of a single chip, improving fault tolerance, and enhancing the reliability and safety of the system. It also reduces the risk of misjudgment, enhances anti-interference capabilities, and adapts to complex working conditions. Furthermore, the circuit board 30, magnet 40, first chip 50, and second chip 60 are all disposed on the inner frame 10, which is located within the mounting cavity of the outer frame 20. This allows for independent processing and assembly of the structure, improving production efficiency.

[0023] According to the wheel speed sensor of this application, the use of dual-chip detection can improve the reliability and stability of wheel speed detection; by using the circuit board 30 to design the internal circuit of the dual-chip wheel speed sensor, the relevant signal stability circuit design can be carried out from the sensor source, avoiding the influence of long-distance parasitic capacitance and parasitic inductance; the outer frame 20 and the inner frame 10 are structurally independent and can be assembled separately, which can improve production efficiency.

[0024] According to some embodiments of this application, a first mating portion 11 is formed at the other end of the inner frame 10, and a second mating portion 21 is formed on the outer frame 20. The first mating portion 11 and the second mating portion 21 are mated and connected to suit the circumferential positioning of the inner frame 10 and the outer frame 20. In this embodiment, by setting the first mating portion 11 and the second mating portion 21 to achieve the circumferential positioning connection between the inner frame 10 and the outer frame 20, it can be ensured that the first chip 50 and the second chip 60 are fixed in position during detection, thereby improving the stability and reliability of detection.

[0025] According to some embodiments of this application, the first mating part 11 and / or the second mating part 21 are configured as a plurality of parts spaced apart circumferentially, and any first mating part 11 is adapted to mate with any second mating part 21. It should be noted that the outer frame 20 is the housing of the wheel speed sensor. When the wheel speed sensor is mounted on a vehicle, the outer frame 20 is used for positioning and installation, such as... Figure 2 As shown, the outer frame 20 has a connecting portion 22 suitable for connection with the vehicle frame. In this embodiment, by providing multiple first mating portions 11 and / or second mating portions 21, and selecting one to achieve mating connection, the circumferential relative position of the inner frame 10 and the outer frame 20 can be adjusted, thereby adjusting the relative position of the first chip 50, the second chip 60 and the wheel. This ensures that the magnet 40, the first chip 50 and the second chip 60 can adapt to the wheel angle, accurately realize wheel speed detection, and thus improve the accuracy and reliability of wheel speed detection.

[0026] In some embodiments, such as Figure 3 , 4 As shown, the first mating part 11 is constructed as a protrusion provided on the outer peripheral surface of the end of the inner frame 10; as Figure 6 As shown, the second mating part 21 is constructed as a groove on the inner circumferential surface of the outer frame 20; the outer frame 20 and the inner frame 10 are circumferentially limited and connected by the engagement of the protrusion and the groove.

[0027] Furthermore, such as Figure 1 , 2 and Figure 5 As shown, in some embodiments, the wheel speed sensor also includes a cover plate 80, which is connected to the outer frame 20 and is disposed at the outer end of the inner frame 10. After the inner frame 10 and the outer frame 20 are assembled and connected, the inner frame 10 can be axially limited by assembling the cover plate 80 to the outer frame 20, thereby achieving stable assembly of the outer frame 20 and the inner frame 10.

[0028] According to some embodiments of this application, a first mounting groove 12 is formed at one end of the inner frame 10, and a first chip 50 and a second chip 60 are spaced apart in the first mounting groove 12 along a first direction; the circuit board 30 has interfaces formed on both sides in the first direction, and the two interfaces are adapted to be connected to the first chip 50 and the second chip 60 respectively via connecting wires. In this embodiment, as... Figure 3 , 4 As shown, the first chip 50 and the second chip 60 are positioned and installed by setting the first mounting slot 12; as Figure 1 As shown, the circuit board 30 has two independent interfaces, namely the first interface 31 and the second interface 32. The first chip 50 is connected to the first interface 31 through the first connecting line 71, and the second chip 60 is connected to the second interface 32 through the second connecting line 72. If one chip or interface fails due to physical damage, electrical fault or software error, the other chip can still work normally, which can prevent the wheel speed sensor from being completely paralyzed. At the same time, the two interfaces are connected to the chip through independent connecting lines, which can avoid signal crosstalk and improve the accuracy of wheel speed detection.

[0029] According to some embodiments of this application, a clearance channel suitable for the passage of connecting wires is formed between the inner frame 10 and the outer frame 20, and the clearance channel connects to the first mounting groove 12. In this embodiment, by providing a clearance channel, the connecting wire can pass through the clearance channel, with one end connected to the first chip 50 or the second chip 60 in the first mounting groove 12, and the other end connected to the corresponding interface of the circuit board 30. The clearance channel in this embodiment can be realized by processing on the outer periphery of the inner frame 10 or the inner wall of the outer frame 20, which is a simple processing method and helps to improve production efficiency.

[0030] Among them, such as Figure 1 As shown, the clearance channel is constructed in two parts, namely the first clearance channel 91 and the second clearance channel 92, which are respectively connected to the two ends of the first mounting groove 12 in the first direction, so that the two first connecting lines 71 and the second connecting line 72 can pass through respectively.

[0031] In some embodiments, a first mounting portion is formed at one end of the inner frame 10, and the aforementioned first mounting groove 12 is formed on the outer end face of the first mounting portion, such as... Figure 3 As shown, the first mounting portion also forms a third mounting groove 14, in which the magnet 40 is disposed. Further, a portion of the outer peripheral wall of the first mounting portion is constructed as a cylindrical surface, and the inner wall of the outer frame 20 is also constructed as a cylindrical surface. This portion of the outer peripheral wall of the first mounting portion mates with the inner wall of the outer frame 20, achieving stable assembly of the outer frame 20 and the inner frame 10, thereby preventing arbitrary relative movement between the outer frame 20 and the inner frame 10. Even further, a portion of the outer peripheral wall of the first mounting portion is constructed as a plane, and a gap exists between this plane and the cylindrical inner wall of the outer frame 20; this gap serves as the aforementioned clearance channel.

[0032] According to some embodiments of this application, the inner frame 10 has a second mounting groove 13, and the circuit board 30 is disposed in the second mounting groove 13; the circuit board 30 has at least one positioning hole, and at least one positioning post 16 that mates with the positioning hole is formed in the second mounting groove 13. In this embodiment, as... Figure 1 As shown, the second mounting slot 13 provides the mounting base for the circuit board 30, and the positioning pin 16 and positioning hole cooperate to limit the circuit board 30, so that it is fixed on the inner frame 10, thereby achieving stable assembly of the circuit board 30 and improving the stability and accuracy of wheel speed detection.

[0033] According to some embodiments of this application, the bottom wall of the second mounting groove 13 is formed with a clearance hole 15, and the interface on the side near the bottom wall is... Figure 4 The second interface 32 shown is positioned directly opposite the clearance hole 15 along the first direction. In this embodiment, the clearance hole 15 provides a channel for the second connecting line 72 to connect from the bottom wall of the second mounting groove 13 to the second interface 32 on the circuit board 30, so that the circuit board 30 and the second chip 60 can be electrically connected through the second connecting line 72.

[0034] In some embodiments, the inner frame 10 has a second mounting area, and a portion of the outer peripheral wall of the second mounting area mates with the inner wall of the outer frame 20 to achieve a stable assembly connection. Further, the second mounting area has the aforementioned second mounting groove 13, and a gap is formed between the bottom wall of the second mounting groove 13 and the outer frame 20; after the circuit board 30 is disposed in the second mounting groove 13, a gap is also formed between the open side surface of the circuit board 30 and the outer frame 20; these two gaps are respectively connected to one of the aforementioned two clearance channels, so that the connecting wire can extend to the circuit board 30 and achieve an electrical connection with the circuit board 30.

[0035] According to some embodiments of this application, the circuit board 30 includes a circuit board body and a protection circuit, a processing unit, a voltage regulator circuit, and a filter circuit disposed on the circuit board body, wherein one end of the protection circuit is connected to the power input node V. S1 Electrical connection; the processing unit is communicatively connected to the first chip 50 and the second chip 60 to receive and process the detection signals generated by the first chip 50 and the second chip 60; the power input terminal V of the processing unit S2The processing unit is electrically connected to the other end of the protection circuit, and its ground terminal GND2 is electrically connected to the ground node GND1. The processing unit has a first output terminal A and a second output terminal B to output the processed output signal. A voltage regulator circuit is connected to the other end of the protection circuit and the ground node GND1 to stabilize the voltage of the processing unit. A filter circuit is connected to the ground node GND1 and the processing unit to filter out high-frequency noise signals in the output signal. In this embodiment, the protection circuit can prevent damage to the circuit board 30 or other components, improving circuit safety. The voltage regulator circuit can stabilize the voltage across the processing unit, preventing damage to the processing unit due to overvoltage and preventing voltage fluctuations from introducing interference and causing errors in the output signal. The processing unit can receive and process the first detection signal collected by the first chip 50 and the second detection signal collected by the second chip 60, process and analyze the first and second detection signals to obtain the corresponding first and second output signals, and output the processed first output signal through the first output terminal A and the processed second output signal through the second output terminal B. After the first and second output signals are output to an external system, the corresponding first and second wheel speeds can be obtained through calculation and analysis, thereby realizing wheel speed detection. By setting up a filtering circuit to remove high-frequency noise interference from the first and second output signals, the reliability and stability of wheel speed detection are improved. Specifically, the first output terminal A is connected to the first output node VoutA of the circuit, and the second output terminal B is connected to the second output node VoutB of the circuit.

[0036] According to some embodiments of this application, the protection circuit includes a first diode D and a resistor Rp, wherein the anode of the first diode D is connected to the power supply connection node V. S1 Electrical connection; one end of resistor Rp is electrically connected to the cathode of the first diode D, and the other end of resistor Rp is connected to the power input terminal V of the processing unit. S2 Connected. In this embodiment, by setting a unidirectional first diode D, reverse power connection can be prevented, avoiding damage to subsequent circuits due to reverse power supply; by setting a resistor Rp, which is connected in series between the first diode D and the processing unit, the maximum current flowing into the processing unit can be limited, preventing overcurrent damage; by utilizing the combined effect of the forward voltage drop of the first diode D and the voltage drop of the resistor Rp, the input voltage of the processing unit can also be reduced.

[0037] According to some embodiments of this application, the voltage regulator circuit includes a first capacitor C1 and a second diode ZD. One end of the first capacitor C1 is electrically connected to the other end of the resistor Rp, and the other end of the first capacitor C1 is electrically connected to the ground node GND1. The cathode of the second diode ZD is electrically connected to the connection node between the first capacitor C1 and the resistor Rp, and the anode of the second diode ZD is electrically connected to the ground node GND1. In this embodiment, by setting the first capacitor C1, low-frequency noise on the power line can be filtered out, stabilizing the power supply voltage of the processing unit; by setting the second diode ZD, when the power supply voltage exceeds a set value, reverse breakdown occurs, clamping the voltage to a safe value, which can prevent overvoltage damage to the processing unit.

[0038] According to some embodiments of this application, the filtering circuit includes a second capacitor C2 and a third capacitor C3. One end of the second capacitor C2 is electrically connected to the second output terminal B, and the other end of the second capacitor C2 is electrically connected to the ground node GND1. One end of the third capacitor C3 is electrically connected to the first output terminal A, and the other end of the third capacitor C3 is electrically connected to the ground node GND1. In this embodiment, by setting the second capacitor C2 and the third capacitor C3, high-frequency noise in the first output signal and the second output signal output by the processing unit can be filtered out, thereby improving the reliability and sensitivity of wheel speed detection.

[0039] like Figure 7 As shown, the circuit design described above is integrated on the circuit board 30 of this application, which can achieve stable signal output. In a specific embodiment, the first diode D is a 1N4007 type, the resistor Rp is 100Ω; the first capacitor C1 is 100nF, the second capacitor C2 and the third capacitor C3 are 10nF; the voltage regulation voltage of the second diode ZD is 12V.

[0040] Figure 8 This is a spectrum of the output signal from the wheel speed sensor without stability circuit processing. The spectrum was obtained from the chip's detection signal via Fourier analysis. Figure 8 As can be seen, there is significant energy at 80,000 Hz in the frequency spectrum, while the wheel speed detection signal is a low-frequency signal; therefore, it is necessary to filter out the high-frequency energy signal. To address this, the wheel speed output signal is processed using the circuit board 30 of this application. Figure 9 The spectrum of the wheel speed output signal after being processed by the stability circuit of the circuit board 30 described above is shown in the figure. Figure 9 As can be seen, high-frequency energy has been filtered out, retaining only the low-frequency effective wheel speed output signal, thus improving the reliability of the wheel speed output signal. Furthermore, due to... Figure 9 It can be seen that some glitches still exist in the processed wheel speed output signal (e.g., the normal pulse signal width is greater than 0.2ms, while the glitches are less than 0.02ms). Further software processing can be used to remove these glitches. Figure 10The pulse signal fluctuation shown is relatively small (less than 0.02ms), which achieves glitch filtering and further improves the accuracy of wheel speed detection. Among these, Figure 10 In the pulse signals shown, C1-C2 is a normal pulse, and C3-C4 is a glitch.

[0041] In the description of this application, 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," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application 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 application.

[0042] In the description of this application, "first feature" and "second feature" may include one or more of the features.

[0043] In the description of this application, "multiple" means two or more.

[0044] In the description of this application, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or the first and second features being in contact through another feature between them.

[0045] In the description of this application, the terms "above," "over," and "on top" for the first feature and the second feature include the first feature being directly above or diagonally above the second feature, or simply indicate that the first feature is at a higher horizontal level than the second feature.

[0046] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "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 this application. In this specification, the illustrative expressions of the above terms do not necessarily refer 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.

[0047] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A wheel speed sensor, characterized in that, include: An inner frame and an outer frame, wherein the outer frame has an internal mounting cavity, and the inner frame is disposed within the mounting cavity; A first chip and a second chip are disposed at one end of the inner frame; A magnet is disposed on the inner frame, and the magnet is disposed opposite to the first chip and the second chip along the axial direction of the inner frame; A circuit board is disposed on the inner frame, and the first chip and the second chip are both electrically connected to the circuit board.

2. The wheel speed sensor according to claim 1, characterized in that, The inner frame has a first mating part at the other end, and the outer frame has a second mating part. The first mating part and the second mating part are connected to each other to limit the circumferential movement of the inner frame and the outer frame.

3. The wheel speed sensor according to claim 2, characterized in that, The first mating part and / or the second mating part are configured as a plurality of parts spaced apart along the circumference, and any first mating part is adapted to mate and connect with any second mating part.

4. The wheel speed sensor according to claim 1, characterized in that, One end of the inner skeleton is formed with a first mounting groove, and the first chip and the second chip are disposed in the first mounting groove at intervals along a first direction; The circuit board has interfaces on both sides in the first direction, and the two interfaces are respectively connected to the first chip and the second chip via connecting lines.

5. The wheel speed sensor according to claim 4, characterized in that, A clearance channel is formed between the inner frame and the outer frame to facilitate the passage of the connecting line, and the clearance channel is connected to the first mounting slot.

6. The wheel speed sensor according to claim 4, characterized in that, The inner frame has a second mounting groove, and the circuit board is disposed in the second mounting groove; the circuit board has at least one positioning hole, and at least one positioning post that mates with the positioning hole is formed in the second mounting groove.

7. The wheel speed sensor according to claim 1, characterized in that, The circuit board includes: The circuit board body and the protection circuit, processing unit, voltage regulator circuit and filter circuit disposed on the circuit board body, wherein, One end of the protection circuit is electrically connected to the power supply access node; The processing unit is communicatively connected to the first chip and the second chip to receive and process the detection signals generated by the first chip and the second chip. The power input terminal of the processing unit is electrically connected to the other end of the protection circuit, the ground terminal of the processing unit is electrically connected to the grounding node, and the processing unit has a first output terminal and a second output terminal to be adapted to output the processed output signal. The voltage regulator circuit is connected to the other end of the protection circuit and the grounding node respectively, and is used to stabilize the voltage of the processing unit; The filtering circuit is connected to the grounding node and the processing unit respectively, and is used to filter out high-frequency noise signals in the output signal.

8. The wheel speed sensor according to claim 7, characterized in that, The protection circuit includes: A first diode, the anode of which is electrically connected to the power access node; A resistor, one end of which is electrically connected to the cathode of the first diode, and the other end of which is connected to the power input terminal of the processing unit.

9. The wheel speed sensor according to claim 8, characterized in that, The voltage regulator circuit includes: A first capacitor, one end of which is electrically connected to the other end of the resistor, and the other end of which is electrically connected to the grounding node; The second diode has its cathode electrically connected to the connection node between the first capacitor and the resistor, and its anode electrically connected to the ground node.

10. The wheel speed sensor according to claim 7, characterized in that, The filtering circuit includes: The second capacitor has one end electrically connected to the second output terminal and the other end electrically connected to the grounding node. The third capacitor has one end electrically connected to the first output terminal and the other end electrically connected to the grounding node.

Images