Eddy current sensor

Abstract

The present application discloses an eddy current sensor, which includes a rotor and a coil assembly. The coil assembly includes a circuit board, a receiving coil, and an excitation coil. The receiving coil includes a first coil and a second coil. The first coil includes a plurality of coil segments connected in sequence. Each coil segment includes a first segment and a second segment. A cylindrical surface is defined that is coaxial with the yoke and passes through the connection point of the first segment and the second segment. The first segment and the second segment are respectively located on either side of the cylindrical surface. The diameter of the yoke passing through the connection point is defined as a preset diameter. The first segment and the second segment are respectively located on either side of the preset diameter. The first segment and the second segment are each composed of at least two wires extending in a straight direction. The second coil has the same structure as the first coil, and the sine coil has the same structure as the cosine coil. The excitation coil is mounted on the circuit board and arranged around the receiving coil. Through the above arrangement, the resolution, signal-to-noise ratio, and anti-interference performance of the eddy current sensor can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of detection equipment, and in particular to an eddy current sensor. Background Art

[0002] In the current detection field, eddy current sensors based on electromagnetic induction and without the need for magnets have obvious advantages in terms of small size and weight, low cost and strong robustness.

[0003] The key to the performance design of eddy-current sensors lies in their receiving coils. Existing eddy-current sensors typically have a two-phase sinusoidal receiving coil structure (sinusoidal and cosine phases). Each phase consists of one or two groups, each group containing two turns. Each turn is distributed segmentally across two layers of the PCB, forming a complete, closed sinusoidal trajectory.

[0004] Eddy current sensors can increase their output signal amplitude, thereby improving their signal-to-noise ratio and anti-interference capabilities. The output signal amplitude of an eddy current sensor is the amplitude of the induced voltage in its receiving coil. This amplitude is primarily influenced by the width of the coil's sensing area, the total effective sensing area, and the number of turns per phase.

[0005] For current eddy current sensors, due to the inherent low design freedom of the sinusoidal routing of the receiving coil, its maximum pole pair number and number of turns per phase will be limited by the routing density, and the total effective sensing area utilization of the coil under a certain sensing area width is not high, which will restrict the improvement of important performance of the eddy current sensor such as resolution, signal-to-noise ratio and anti-interference. Summary of the Invention

[0006] In order to address the deficiencies of the prior art, the present application aims to provide an eddy current sensor with good resolution, signal-to-noise ratio and anti-interference performance.

[0007] To achieve the above objectives, this application adopts the following technical solutions:

[0008] An eddy current sensor, which includes a rotor and a coil assembly, the rotor includes a yoke and a plurality of teeth, the yoke is a circular ring structure, each tooth extends radially along the yoke, and the plurality of teeth are evenly distributed on the outer peripheral surface of the yoke, and a tooth slot is formed between two adjacent teeth. Along the circumference of the yoke, the width of the tooth slot is consistent with the width of the tooth and is defined as a preset width; the coil assembly is located on one side of the rotor along the axial direction of the yoke, the coil assembly includes a circuit board, a receiving coil and an excitation coil, the receiving coil includes a cosine coil and a sine coil mounted on the circuit board, the cosine coil includes a first coil and a second coil, the first coil includes a plurality of coil segments connected in sequence, each coil segment includes a first segment and a second segment, and along the circumference of the yoke, the width of the first segment and the width of the second segment are both preset width, defining a cylindrical surface coaxial with the yoke and passing through the connection point of the first section and the second section, the first section and the second section are respectively located on both sides of the cylindrical surface, the diameter of the yoke passing through the connection point is defined as a preset diameter, the first section and the second section are respectively located on both sides of the preset diameter, the first section and the second section are each composed of at least two wires extending in a straight line direction; the second coil has the same structure as the first coil, and when the second coil moves a distance of the preset width along the circumference of the yoke, the second coil overlaps with the first coil axially along the yoke; the sine coil has the same structure as the cosine coil, and when the sine coil moves a distance of half the preset width along the circumference of the yoke, the sine coil overlaps with the cosine coil axially along the yoke; the excitation coil is mounted on the circuit board and arranged around the receiving coil.

[0009] Furthermore, the cosine coil can generate a sine envelope waveform signal, and the sine coil can generate a cosine envelope waveform signal.

[0010] Furthermore, the first section includes a first part and a second part extending radially along the yoke and a third part extending radially perpendicular to the yoke, and the first part, the third part and the second part are connected in sequence; the structure of the second section is basically the same as that of the first section.

[0011] Furthermore, the first section includes a first part that forms an acute angle with the radial direction of the yoke, a second part that forms an acute angle with the radial direction of the yoke, and a third part that extends perpendicular to the radial direction of the yoke, and the first part, the third part and the second part are connected in sequence; the structure of the second section is basically the same as that of the first section.

[0012] Furthermore, the first section also includes a first transition portion, which extends along a straight line, is connected between the first portion and the third portion, and enables the first portion and the third portion to satisfy a first arrangement; and / or the first transition portion is connected between the second portion and the third portion, and enables the second portion and the third portion to satisfy a second arrangement.

[0013] Furthermore, the first section includes a first portion forming an acute angle with the radial direction of the yoke and a second portion forming an acute angle with the radial direction of the yoke, the first portion and the second portion are connected; the structure of the second section is consistent with that of the first section.

[0014] Furthermore, the first section also includes a second transition portion, which is connected to the first portion and the second portion. The second transition portion enables the angle formed by the first portion and the second portion to meet a preset angle.

[0015] Furthermore, the circuit board includes an upper layer and a lower layer distributed axially along the yoke, and the connection point of the first section and the second section is defined as a preset point. The coil section includes an upper section installed on the upper layer and a lower section installed on the lower layer. The first section includes a first upper sub-segment whose distance from the preset point is zero to one-half of the preset width and a first lower section whose distance from the preset point is one-half of the preset width to the preset width. The second section includes a second upper sub-segment whose distance from the preset point is zero to one-half of the preset width and a second lower sub-segment whose distance from the preset point is one-half of the preset width to the preset width. The first upper sub-segment is connected to the second upper sub-segment, the upper section includes the first upper sub-segment and the second upper sub-segment, and the lower section includes the first lower section and the second lower sub-segment.

[0016] To achieve the above objectives, this application adopts the following technical solutions:

[0017] An eddy current sensor, the eddy current sensor includes a mover and a coil assembly, the mover includes a plurality of second teeth, the plurality of second teeth are evenly arranged along a preset straight line direction, a second tooth groove is formed between two adjacent second teeth, and along the preset straight line direction, the width of the second tooth groove is consistent with the width of the second tooth and is defined as the second width; the coil assembly is located on one side of the plurality of second teeth along a first direction, the first direction is perpendicular to the preset straight line direction, the coil assembly includes a circuit board, a receiving coil and an excitation coil, the receiving coil includes a cosine coil and a sine coil mounted on the circuit board, the cosine coil includes a first coil and a second coil, the first coil includes a plurality of coil segments connected in sequence, each coil segment includes The invention comprises a first section and a second section, and along a preset straight line direction, the width of the first section and the width of the second section are both the second width, the first section and the second section are centrally symmetrical structures about the connection point between the two sections, and the first section and the second section are both composed of at least two conductive wires extending along the straight line direction; the second coil has the same structure as the first coil, and when the second coil moves a distance of the second width along the preset straight line direction, the second coil overlaps with the first coil along the first direction; the sine coil has the same structure as the cosine coil, and when the sine coil moves a distance of half the second width along the preset straight line direction, the sine coil overlaps with the cosine coil along the first direction; the excitation coil is mounted on the circuit board and arranged around the receiving coil.

[0018] Further, the first section includes a first part and a second part extending along the second direction and a third part extending along a preset straight line direction, and the first part, the third part and the second part are connected in sequence; the second direction is perpendicular to the first direction and perpendicular to the preset straight line direction; or, the first section includes a first part that forms an acute angle with the second direction, a second part that forms an acute angle with the second direction and a third part extending along the preset straight line direction, and the first part, the third part and the second part are connected in sequence; or, the first section includes a first part that forms an acute angle with the second direction and a second part that forms an acute angle with the second direction, and the first part and the second part are connected; the structure of the second section is consistent with the structure of the first section.

[0019] The cosine coil of the above-mentioned eddy current sensor includes a first coil and a second coil. The first coil includes a plurality of coil segments connected in sequence. Each coil segment includes a first segment and a second segment. The first segment and the second segment are both composed of at least two wires extending in a straight direction. The second coil has the same structure as the first coil, and the sine coil has the same structure as the cosine coil. Therefore, by adjusting the length and angle of the wire of each coil segment, the number of pole pairs of the eddy current sensor, the number of turns per phase, and the effective sensing area can be increased under the condition of a certain volume of the eddy current sensor, thereby improving the resolution, signal-to-noise ratio and anti-interference performance of the eddy current sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of the structure of the eddy current sensor provided in an embodiment of the present application.

[0021] Figure 2 This is a front view of the eddy current sensor provided in an embodiment of the present application.

[0022] Figure 3 For the embodiment of this application Figure 2 A partial enlarged view of point A in the middle.

[0023] Figure 4 This is a structural cross-sectional view of the circuit board and coil assembly of the eddy current sensor provided in an embodiment of the present application.

[0024] Figure 5 This is a cross-sectional view of the structure of the circuit board and coil assembly of the eddy current sensor provided in an embodiment of the present application from another angle.

[0025] Figure 6 This is a schematic structural diagram of the first cosine coil of the eddy current sensor provided in an embodiment of the present application.

[0026] Figure 7 Schematic diagram of the induced voltage and envelope of the cosine coil of the eddy current sensor provided in an embodiment of the present application.

[0027] Figure 8Schematic diagram of the induced voltage of the cosine coil and sine coil of the eddy current sensor provided in an embodiment of the present application.

[0028] Figure 9 A schematic structural diagram of the second cosine coil of the eddy current sensor provided in an embodiment of the present application.

[0029] Figure 10 This is a schematic structural diagram of the third cosine coil of the eddy current sensor provided in an embodiment of the present application.

[0030] Figure 11 This is a schematic structural diagram of the coil segment of the eddy current sensor provided in an embodiment of the present application.

[0031] Figure 12 A schematic structural diagram of another eddy current sensor provided in an embodiment of the present application.

[0032] Figure 13 A schematic structural diagram of a first type of cosine coil of another eddy current sensor provided in an embodiment of the present application.

[0033] Figure 14 A schematic structural diagram of a second cosine coil of another eddy current sensor provided in an embodiment of the present application.

[0034] Figure 15 A schematic structural diagram of a third cosine coil of another eddy current sensor provided in an embodiment of the present application. DETAILED DESCRIPTION

[0035] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the specific implementation of the present application will be clearly and completely described below in conjunction with the drawings in the implementation of the present application.

[0036] It should be noted that the words "first", "second" and similar terms used in the specification and claims of this application do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "an" do not indicate a quantity limitation, but rather indicate the presence of at least one. "Multiple" or "several" means at least two. Unless otherwise specified, words such as "front", "back", "left", "right", "bottom" and / or "top" are used for ease of description only and are not limited to one position or one spatial orientation. Words such as "include" or "comprising" and similar terms mean that the elements or objects appearing before "include" or "comprising" include the elements or objects listed after "include" or "comprising" and their equivalents, and do not exclude other elements or objects. Words such as "connected" or "connected" and similar terms are not limited to physical or mechanical connections, and may include electrical connections, whether direct or indirect.

[0037] As used in this specification and the appended claims, the singular forms "a," "an," "said," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0038] like Figure 1 and Figure 2 As shown, the present application provides an eddy current sensor 100, which can realize the absolute angular position measurement of a rotating component. For example, the eddy current sensor 100 can realize the absolute angular position measurement of a motor rotor.

[0039] The eddy current sensor 100 includes a rotor 11 and a coil assembly 12. When the eddy current sensor 100 detects the absolute angular position of a motor, the rotor 11 is fixed to the motor's rotor. When the eddy current sensor 100 detects the absolute angular position of other rotating components, the rotor 11 is fixed to the rotating component. The coil assembly 12 is located on one side of the rotor 11 and has a predetermined spacing therebetween. This predetermined spacing enables the coil assembly 12 and the rotor 11 to cooperate for non-contact measurement.

[0040] like Figures 1 to 3 As shown, specifically, the rotor 11 includes a yoke 111 and a plurality of teeth 112, which are integrally formed. The yoke 111 has a circular ring structure, with each tooth 112 extending radially along the yoke 111. The plurality of teeth 112 are evenly distributed on the outer circumference of the yoke 111, giving the rotor 11 a substantially gear-like structure and enhancing its stability during rotation. A tooth slot 113 is formed between adjacent teeth 112. Along the circumference of the yoke 111, the width of the tooth slot 113 is consistent with the width of the tooth 112, and both are defined as a predetermined width D1. It should be noted that the distance between the middle positions of the tooth portion 112 along the circumference of the yoke portion 111 is the above-mentioned preset width D1, and the distance between the middle positions of the tooth grooves 113 along the circumference of the yoke portion 111 is the above-mentioned preset width D1; a cylindrical surface 101 having the same axis as the yoke portion 111 is defined, and the cylindrical surface 101 divides the tooth portion 112 into two parts of basically the same length along the radial direction of the yoke portion 111. The intersection of the cylindrical surface 101 and the tooth portion 112 is the middle position of the tooth portion 112, and the intersection of the cylindrical surface 101 and the tooth groove 113 is the middle position of the tooth groove 113.

[0041] It should be noted that the preset width D1 is essentially the length of an arc on the cylindrical surface 101. If the number of pole pairs of the eddy current sensor 100 is p, then the central angle subtended by the preset width D1 is π / p.

[0042] like Figures 2 to 5As shown, specifically, the coil assembly 12 is located on one side of the rotor 11 along the axial direction of the yoke 111. The coil assembly 12 includes a circuit board 121, a receiving coil 122 and an excitation coil 123. The excitation coil 123 can pass high-frequency alternating current, thereby generating an excitation magnetic field; the receiving coil 122 can sense changes in the magnetic field, thereby outputting an induced voltage. The receiving coil 122 and the excitation coil 123 are both mounted on the circuit board 121, and the excitation coil 123 is arranged around the receiving coil 122. In the present application, the excitation coil 123 is basically annular, and the axis of the excitation coil 123 basically coincides with the axis of the yoke 111.

[0043] It should be noted that, in the present application, the circuit board 121 may be a PCB (Printed Circuit Board).

[0044] In this embodiment, the receiving coil 122 includes a cosine coil 200 and a sine coil 1221 , and both the cosine coil 200 and the sine coil 1221 are mounted on the circuit board 121 .

[0045] It should be noted that the receiving coil 122 needs to meet the following constraints:

[0046] (1) The number of pole pairs of the eddy current sensor 100 is p. The cosine coil 200 and the sine coil 1221 each include n groups of coils, where n is an integer greater than or equal to 1, and each group of coils includes two turns of coils. The two turns of coils have a total of p periods on the circumference, and the central angle of one period is θturn = 2π / p. The definition of the period will be described below and will not be repeated here.

[0047] (2) The circuit board 121 includes an upper layer 1211 and a lower layer 1212 axially distributed along the yoke 111. The two turns of the coil are distributed in sections on the upper layer 1211 and the lower layer 1212 of the circuit board 121 (i.e., two adjacent sections are located on the upper layer 1211 and the lower layer 1212, respectively). The central angle of each section is θset = π / p. The adjacent sections are connected by vias 1213 on the circuit board 121. The definition of the two adjacent sections will be described below and will not be repeated here.

[0048] (3) The two turns of the coil are exactly the same, with only a phase difference of π / p.

[0049] (4) The two turns of coils are connected in reverse series on the circuit board 121 through wiring processing (two coils of the same specifications are combined in opposite directions (clockwise + counterclockwise), electrically connected in series to form a differential pair).

[0050] (5) If the number n of the cosine coil 200 and the sine coil 1221 groups is greater than 1, the phase difference between each group of coils is θset / 2n, and each group of coils is connected in series in a forward direction through wiring processing on the circuit board 121 (two coils of the same specifications are combined in the same direction (both clockwise or counterclockwise), electrically connected in series, and signal superposition is formed).

[0051] (6) The phase difference between the cosine coil 200 and the sine coil 1221 is θset / 2, and the cosine coil 200 and the sine coil 1221 are electrically insulated.

[0052] (7) The rotor 11 is made of metal material and has a gear-like structure. The central angle subtended by the tooth portion 112 is θset=π / p, and the central angle subtended by the tooth slot 113 is θset=π / p. The radial dimension of the tooth slot 113 in the yoke 111 is required to ensure that the projection of the induction area of the receiving coil 122 is within the projection of the tooth slot 113.

[0053] (8) The excitation coil 123 is annular and is located on the upper layer 1211 or the lower layer 1212 of the circuit board 121. The radius of the excitation coil 123 is greater than the maximum distance between the receiving coil 122 and the axis of the yoke 111, and the minimum distance between the excitation coil 123 and the receiving coil 122 is close to the minimum line spacing required by the circuit board 121.

[0054] Through the above configuration, the eddy current sensor 100 of the present application can perform the same measurement function as the eddy current sensor 100 with a sinusoidal trace.

[0055] It should be noted that the central angle corresponding to the preset width D1 is the aforementioned θset=π / p.

[0056] like Figure 3 and Figure 6 As shown in FIG, as an implementation, the cosine coil 200 includes a first coil 21 and a second coil 22. It should be noted that the two turns of the cosine coil 200 in the above constraint condition are the first coil 21 and the second coil 22; and as in the above constraint condition (1), the cosine coil 200 may include n groups of coils, each group of coils including the first coil 21 and the second coil 22.

[0057] The first coil 21 includes a plurality of sequentially connected coil segments 211. Each coil segment 211 includes a first segment 2111 and a second segment 2112. Along the circumference of the yoke 111, the width of the first segment 2111 and the width of the second segment 2112 are both a predetermined width D1. The cylindrical surface 101 also passes through the connection point between the first segment 2111 and the second segment 2112. The first segment 2111 and the second segment 2112 are located on either side of the cylindrical surface 101, i.e., the first segment 2111 and the second segment 2112 are located on the inner and outer sides of the cylindrical surface 101, respectively. The diameter of the yoke 111 passing through the connection point between the first segment 2111 and the second segment 2112 is defined as a predetermined diameter 103. The first segment 2111 and the second segment 2112 are located on either side of the predetermined diameter 103, i.e., the first segment 2111 and the second segment 2112 are located on either side of the predetermined diameter 103 along the circumference of the yoke 111. Specifically, the first segment 2111 and the second segment 2112 are each formed of at least two conductive wires extending in a straight line. It should be noted that each coil segment 211 forms a period, i.e., the central angle subtended by each coil segment 211 is θturn = 2π / p; the central angle subtended by the first segment 2111 and the second segment 2112 is θset = π / p, thereby satisfying the aforementioned constraint (1).

[0058] Through the above arrangement, each period of the first coil 21 (i.e., each coil segment 211) can be composed of one or more segments of wire, and each segment of wire extends in a straight line. The length of each segment of wire and the angle between the multiple segments of wire can be adjusted according to actual conditions. The above arrangement allows each segment of wire in the coil segment 211 of the present application to have design freedom. This design freedom refers to the fact that the length of each segment of wire in the first segment 2111 and the second segment 2112 and the radial inclination angle relative to the yoke 111 can be adjusted, thereby making the coil segment 211 more flexible and deformable. As a result, the eddy current sensor 100 of the present application is more suitable for adjusting the effective sensing area utilization, the number of turns per phase, and the number of pole pairs according to actual conditions, compared to existing sinusoidal eddy current sensors. It also has a higher designable maximum effective sensing area utilization, the designable maximum number of turns per phase, and the designable maximum number of pole pairs, thereby improving the resolution, signal-to-noise ratio, and anti-interference performance of the eddy current sensor 100.

[0059] For example, by adjusting the radial inclination angle of the wires in the first section 2111 and the second section 2112 relative to the yoke 111, the projections of the sensing areas of the first section 2111 and the second section 2112 can be made into different shapes, thereby increasing the utilization rate of the effective sensing area; by adjusting the angle and length between the wires in the first section 2111 and the second section 2112, the shape of each coil segment 211 can be adapted to the routing density brought about by the increase in the number of turns of the first coil 21, thereby obtaining a higher designable maximum number of turns per phase; by adjusting the preset width D1 of each coil segment 211 as a whole, the number of pole pairs of the eddy current sensor 100 can be increased to adapt to different application requirements and detection requirements.

[0060] It should be noted that if the application requires increasing the number of poles of the eddy current sensor 100 (for example, when applied to a multi-pole motor) or the number of turns per phase (for example, when the output signal amplitude needs to be increased), the sinusoidal coil is often difficult to meet the requirements of a multi-pole design with matching pole numbers or a dense design with a large number of turns per phase under a certain size, resulting in an exponential loss of the electrical angle measurement resolution of the motor or the output signal amplitude and its signal-to-noise ratio not meeting the detection requirements. In the present application, since each section of the wire of the coil segment 211 of the present application has design freedom, the structural flexibility and deformability of the coil segment 211 are relatively high. Through but not limited to the adjustment embodiments provided in the present application, the maximum number of pole pairs and the maximum number of turns per phase of the eddy current sensor 100 of the present application can be increased. That is, compared with the sinusoidal coil, the resolution, signal-to-noise ratio and anti-interference performance of the eddy current sensor 100 of the present application are improved.

[0061] In this embodiment, the second coil 22 has the same structure as the first coil 21. When the second coil 22 is displaced by a predetermined width D1 along the circumferential direction of the yoke 111, the second coil 22 and the first coil 21 overlap axially along the yoke 111. In other words, the aforementioned constraint (2) is satisfied: "The two turns of the coils are identical, with only a phase difference of π / p."

[0062] Among them, the beneficial effects brought by the second coil 22 are basically the same as the beneficial effects brought by the first coil 21, and will not be repeated here.

[0063] It should be noted that the first coil 21 and the second coil 22 enable the length of each section of the cosine coil 200 and the angle between multiple sections of the wire to be adjusted according to actual conditions, thereby increasing the number of pole pairs of the eddy current sensor 100, increasing the number of turns per phase, and increasing the utilization rate of the effective sensing area, thereby improving the resolution, signal-to-noise ratio and anti-interference performance of the eddy current sensor 100.

[0064] In this embodiment, the sine coil 1221 and the cosine coil 200 have the same structure. When the sine coil 1221 moves along the circumference of the yoke 111 by a distance half of the preset width D1, the sine coil 1221 and the cosine coil 200 overlap axially along the yoke 111. That is, the above-mentioned constraint (6) is satisfied: the phase difference between the cosine coil 200 and the sine coil 1221 is θset / 2. At the same time, the sine coil 1221 and the cosine coil 200 are electrically insulated.

[0065] Among them, the beneficial effects brought by the sine coil 1221 are basically the same as the beneficial effects brought by the cosine coil 200, and will not be repeated here.

[0066] It should be noted that the sine coil 1221 and the cosine coil 200 enable the length of each section of the wire of the receiving coil 122 and the angle between multiple sections of the wire to be adjusted according to actual conditions, thereby increasing the number of pole pairs of the eddy current sensor 100, increasing the number of turns per phase of the receiving coil 122, and increasing the utilization rate of the effective sensing area, thereby improving the resolution, signal-to-noise ratio and anti-interference performance of the eddy current sensor 100.

[0067] It should be noted that, unlike the existing sinusoidal routing technology, constraints (1) to (8) extend the routing shape of the receiving coil 122 of the eddy current sensor 100 from the existing sinusoidal shape to any shape: for the routing of the receiving coil 122 of any shape, satisfying the above constraints is a necessary and sufficient condition for the eddy current sensor 100 of the present application to perform the same measurement function as the existing sinusoidal routing eddy current sensor. Based on the above constraints, the design freedom brought by the technical solution of the present application is utilized to design the routing shape of the receiving coil 122. Under the condition that the volume of the eddy current sensor 100 is constant, the number of pole pairs of the eddy current sensor 100 and the number of turns per phase can be increased, and under the condition that the width of the sensing area is constant, the maximum effective sensing area can be obtained, thereby improving the resolution, signal-to-noise ratio and anti-interference performance of the eddy current sensor 100.

[0068] like Figure 7 and Figure 8 As shown, as an implementation, the cosine coil 200 can generate a sinusoidal envelope waveform signal, and the sine coil 1221 can generate a cosine envelope waveform signal. It can be seen that the eddy current sensor 100 of the present application can perform the same measurement function as the eddy current sensor 100 with a sinusoidal trace.

[0069] like Figure 6As shown, as an optional implementation, the first segment 2111 includes a first portion 2111a and a second portion 2111b extending radially along the yoke 111, and a third portion 2111c extending perpendicularly to the radial direction of the yoke 111. That is, the first portion 2111a and the second portion 2111b both extend along a straight line, and when the number of coil segments 211 is sufficient, the first portion 2111a and the second portion 2111b can be considered to be substantially parallel.

[0070] The first section 2111a, the third section 2111c, and the second section 2111b are connected in sequence; the structure of the second section 2112 is substantially identical to that of the first section 2111. Through the above arrangement, the projection M1 of the sensing area of the first section 2111 can be made substantially rectangular, and the projection M2 of the sensing area of the second section 2112 can be made substantially rectangular. It should be noted that the structure of the second section 2112 being substantially identical to that of the first section 2111 refers to a minor difference between the two. The difference between the two structures is that the second section 2112 includes a corresponding portion corresponding to the third section 2111c, and the length of the corresponding portion is shorter than that of the third section 2111c. In other words, the difference between the second section 2112 and the first section 2111 is only the difference in length between the corresponding portion and the third section 2111c.

[0071] It should be noted that this implementation method can obtain the maximum effective sensing area under a certain sensing area width, that is, this implementation method can maximize the utilization rate of the effective sensing area, thereby improving the output signal amplitude and waveform quality, signal-to-noise ratio and anti-interference performance of the eddy current sensor 100.

[0072] like Figure 9 As shown, as an optional implementation, Figure 6 A simple variation of the implementation shown is provided to illustrate one of the design freedoms afforded by the present invention's technical solution. The first section 2111 includes a first portion 2111a that forms an acute angle α with the radial direction of the yoke 111, a second portion 2111b that forms an acute angle β with the radial direction of the yoke 111, and a third portion 2111c that extends perpendicularly to the radial direction of the yoke 111. Specifically, the first portion 2111a and the second portion 2111b extend along a straight line, and the first portion 2111a and the second portion 2111b form an included angle. It should be noted that the acute angle α formed between the first portion 2111a and the radial direction of the yoke 111 can be equal to the acute angle β formed between the second portion 2111b and the radial direction of the yoke 111, or the acute angle α formed between the first portion 2111a and the radial direction of the yoke 111 can be different from the acute angle β formed between the second portion 2111b and the radial direction of the yoke 111. This means that the positions of the first portion 2111a and the second portion 2111b can be adjusted based on actual conditions.

[0073] Among them, the first section 2111a, the third section 2111c, and the second section 2111b are connected in sequence; the structure of the second section 2112 is substantially identical to that of the first section 2111. Through the above arrangement, the projection M1 of the sensing area of the first section 2111 can be made substantially trapezoidal, and the projection M2 of the sensing area of the second section 2112 can be made substantially trapezoidal. It should be noted that the structure of the second section 2112 is substantially identical to that of the first section 2111, which means that there are minor differences between the two. The difference between the two structures is that the second section 2112 includes a corresponding portion corresponding to the third section 2111c, and the length of the corresponding portion is shorter than the length of the third section 2111c. In other words, the difference between the second section 2112 and the first section 2111 is only the difference in length between the corresponding portion and the third section 2111c.

[0074] like Figure 6 and Figure 9 As shown, in the above two embodiments, the first section 2111 also includes a first transition portion 2111d, the first transition portion 2111d extends along a straight line, the first transition portion 2111d is connected between the first portion 2111a and the third portion 2111c, and the first transition portion 2111d makes the first portion 2111a and the third portion 2111c satisfy the first arrangement mode; and / or the first transition portion 2111d is connected between the second portion 2111b and the third portion 2111c, and the first transition portion 2111d makes the second portion 2111b and the third portion 2111c satisfy the second arrangement mode. The first arrangement, namely, the angle and position between the first portion 2111a and the third portion 2111c, meet the requirements for the use of the first segment 2111, enabling normal operation of the first segment 2111. The second arrangement, namely, the angle and position between the second portion 2111b and the third portion 2111c, meet the requirements for the use of the first segment 2111, enabling normal operation of the first segment 2111. It should be noted that normal operation of the first segment 2111 refers to the fact that the first segment 2111 of the cosine coil 200 does not conflict with the portion of the adjacent sine coil 1221 corresponding to the first segment 2111, thereby preventing routing problems for the cosine coil 200 and the sine coil 1221. The specific length, angle, and starting and ending positions of the first transition portion 2111d are relatively freely adjustable, further enhancing the design freedom of the cosine coil 200.

[0075] It should be noted that, under a certain sensing area width, by adjusting the specific length, angle, start and end positions of the first transition portion 2111d, Figure 6 The implementation shown in the figure obtains the maximum effective sensing area utilization. Specifically: Figure 3As shown, by adjusting the starting and ending positions of the first transition portion 2111d, shortening the length of the first transition portion 2111d, and adjusting the angle of the first transition portion 2111d, the starting and ending positions of the first transition portion 2111d are aligned with the via hole 1213 on the circuit board 121 (see FIG. Figure 4 ) is the shortest. In this case, within a certain sensing area width, the effective sensing area of the eddy current sensor 100 is maximized, i.e., the utilization rate of the effective sensing area is maximized, thereby improving the output signal amplitude and waveform quality, signal-to-noise ratio, and anti-interference performance of the eddy current sensor 100.

[0076] It should be noted that the first arrangement and the second arrangement can be adjusted according to actual needs, and this application does not impose any restrictions.

[0077] For example, the first arrangement can use the first transition portion 2111d to make the transition between the first portion 2111a and the third portion 2111c a non-right-angle or non-sharp-angle transition, thereby avoiding signal interference caused by an increase in distributed capacitance of the wiring.

[0078] The second arrangement can use the first transition portion 2111d to make the transition between the second portion 2111b and the third portion 2111c a non-right-angle or non-sharp-angle transition, thereby avoiding signal interference caused by an increase in distributed capacitance of the wiring.

[0079] like Figure 10 As shown, as another optional implementation, the first section 2111 includes a first portion 2111a that forms an acute angle Ω with the radial direction of the yoke 111 and a second portion 2111b that forms an acute angle γ with the radial direction of the yoke 111, that is, the first portion 2111a and the second portion 2111b both extend along a straight line, and the first portion 2111a and the second portion 2111b form an angle. It should be noted that the acute angle Ω formed by the first portion 2111a and the radial direction of the yoke 111 can be equal to the acute angle γ formed by the second portion 2111b and the radial direction of the yoke 111, and the acute angle Ω formed by the first portion 2111a and the radial direction of the yoke 111 can also be different from the acute angle γ formed by the second portion 2111b and the radial direction of the yoke 111, that is, the positions of the first portion 2111a and the second portion 2111b can be adjusted according to actual conditions.

[0080] The first portion 2111a and the second portion 2111b are connected, and the structure of the second segment 2112 is substantially the same as that of the first segment 2111. With this arrangement, the projection M1 of the sensing area of the first segment 2111 can be substantially triangular, and the projection M2 of the sensing area of the second segment 2112 can be substantially triangular.

[0081] It should be noted that the structure of the second section 2112 is substantially identical to that of the first section 2111, meaning that there are minor differences between the two. The structural differences between the two are that the first section 2111 also includes a second transition portion 2111e, which connects the first section 2111a and the second section 2111b. The second transition portion 2111e ensures that the angle formed by the first section 2111a and the second section 2111b meets a predetermined angle. The predetermined angle can be adjusted according to actual needs and is not limited in this application. However, the second section 2112 does not include the second transition portion 2111e.

[0082] It should be noted that the function of the second transition portion 2111e is basically the same as that of the first transition portion 2111d, and will not be repeated here.

[0083] It should be noted that compared with the existing sinusoidal routing and other implementation methods of the present application, this implementation method is more conducive to designing a higher routing density because the angle between the first part 2111a and the second part 2111b can be adjusted arbitrarily, and is more suitable for meeting the needs of increasing the number of pole pairs and the number of turns per phase. Therefore, when the volume of the eddy current sensor 100 is constant, the eddy current sensor 100 can have a larger maximum designable number of pole pairs and number of turns per phase, thereby improving the maximum pole pairs, resolution, signal-to-noise ratio and anti-interference performance of the adaptable motor of the eddy current sensor 100.

[0084] like Figure 5 and Figure 11 As shown, as an implementation, the circuit board 121 includes an upper layer 1211 distributed along the axial direction of the yoke 111 (refer to Figure 4 ) and lower layer 1212 (refer to Figure 5 ), the connection point between the first section 2111 and the second section 2112 is defined as a preset point 102. It should be noted that the preset point 102 is located on the cylindrical surface 101 coaxial with the yoke 111.

[0085] Specifically, the coil segment 211 includes an upper segment 2113 installed on the upper layer 1211 and a lower segment 2114 installed on the lower layer 1212 . Among them, the first section 2111 includes a first upper sub-segment 2111f whose distance from the preset point 102 is zero to half the preset width D1 and a first lower sub-segment 2111g whose distance from the preset point 102 is half the preset width D1 to the preset width D1, the second section 2112 includes a second upper sub-segment 2112a whose distance from the preset point 102 is zero to half the preset width D1 and a second lower sub-segment 2112b whose distance from the preset point 102 is half the preset width D1 to the preset width D1, the first upper sub-segment 2111f is connected to the second upper sub-segment 2112a, the upper section 2113 includes the first upper sub-segment 2111f and the second upper sub-segment 2112a, and the lower section 2114 includes the first lower sub-segment 2111g and the second lower sub-segment 2112b.

[0086] It should be noted that the upper segment 2113 and the first lower segment 2111g are the "two adjacent segments" in the above constraint condition (2), or the upper segment 2113 and the second lower segment 2112b are the "two adjacent segments" in the above constraint condition (2), thereby satisfying the above constraint condition (2).

[0087] like Figure 12 and Figure 13 As shown, the present application also provides another eddy current sensor 300, which can measure the moving distance of a linear moving component. It should be noted that the linear moving component is any mechanism that can move along a straight line, such as a push rod.

[0088] The eddy current sensor 300 includes a mover 31 and a coil assembly 32. When the eddy current sensor 300 detects the travel distance of a linearly movable component, the mover 31 is fixed to the linearly movable component. In other words, in this embodiment, the eddy current sensor 300 does not include a rotor. The coil assembly 32 is located on one side of the mover 31 and is spaced apart from the mover 31 by a predetermined distance. This predetermined distance enables the coil assembly 32 and mover 31 to cooperate for non-contact measurement.

[0089] Specifically, the mover 31 includes a plurality of second teeth 311, which are evenly arranged along a preset straight line 301. As an optional implementation, the plurality of second teeth 311 are fixed to a linear moving component and evenly arranged along the preset straight line 301.

[0090] More specifically, a second tooth groove 312 is formed between two adjacent second tooth portions 311. Along the predetermined straight line 301, the width of the second tooth groove 312 is the same as the width of the second tooth portion 311, and both are defined as a second width D2. It should be noted that because the plurality of second tooth portions 311 are evenly arranged along the predetermined straight line 301, i.e., the plurality of second tooth portions 311 are equally spaced along the predetermined straight line 301, the second width D2 is the width of the second tooth portion 311 along the predetermined straight line 301, and the second width D2 is the width of the second tooth groove 312 along the predetermined straight line 301.

[0091] Specifically, the coil assembly 32 is located on one side of the plurality of second teeth 311 along a first direction perpendicular to the direction of the predetermined straight line 301. The coil assembly 32 includes a circuit board (not shown), a receiving coil 322, and an excitation coil 323. It should be noted that the receiving coil 322 of the coil assembly 32 in this embodiment differs from the receiving coil 122 of the coil assembly 12 in the previous embodiment only in their arrangement; the circuit board and excitation coil 323 in this embodiment are substantially identical to the circuit board 121 and excitation coil 123 in the previous embodiment.

[0092] In this embodiment, the receiving coil 322 includes a cosine coil 400 and a sine coil 3221 , and both the cosine coil 400 and the sine coil 3221 are mounted on a circuit board.

[0093] In which, the cosine coil 400 includes a first coil 41 and a second coil 42, the first coil 41 includes a plurality of coil segments 411 connected in sequence, each coil segment 411 includes a first segment 4111 and a second segment 4112, along the direction of the preset straight line 301, the width of the first segment 4111 and the width of the second segment 4112 are both the second width D2, and the first segment 4111 and the second segment 4112 are a centrally symmetrical structure about the connection point between the two.

[0094] Specifically, the first segment 4111 and the second segment 4112 are each composed of at least two conductive wires extending in a straight direction.

[0095] Through the above-described arrangement, each coil segment 411 of the first coil 41 can be composed of one or more segments of conductive wire, and each segment of conductive wire extends in a straight line. The length of each segment of conductive wire and the angle between the multiple segments of conductive wire can be adjusted according to actual conditions. The above-described arrangement allows each segment of conductive wire in the coil segment 411 of the present application to have design freedom. This design freedom refers to the fact that the length and inclination angle of each segment of conductive wire in the first segment 4111 and the second segment 4112 relative to the second direction 303 can be adjusted, thereby providing the coil segment 411 with greater structural flexibility and deformability. As a result, the eddy current sensor 300 of the present application is more suitable for adjusting the effective sensing area utilization, number of turns per phase, and period length (i.e., second width D2) according to actual conditions, compared to existing sinusoidal eddy current sensors. It also has a higher designable maximum effective sensing area utilization, designable maximum number of turns per phase, and designable minimum period length, thereby improving the resolution, signal-to-noise ratio, and anti-interference performance of the eddy current sensor 300.

[0096] For example, by adjusting the inclination angle of the conductive wires in the first section 4111 and the second section 4112 relative to the second direction 303, the projections of the sensing areas of the first section 4111 and the second section 4112 can be made into different shapes to accommodate different application and detection requirements. The second direction 303 is perpendicular to the first direction and perpendicular to the direction of the preset straight line 301.

[0097] In this embodiment, the second coil 42 has the same structure as the first coil 41. When the second coil 42 moves a distance of the second width D2 along the preset straight line 301, the second coil 42 overlaps with the first coil 41 along the first direction. The sine coil 3221 has the same structure as the cosine coil 400. When the sine coil 3221 moves a distance of half the second width D2 along the preset straight line 301, the sine coil 3221 overlaps with the cosine coil 400 along the first direction.

[0098] Among them, the beneficial effects brought by the second coil 42 are basically the same as those brought by the first coil 41, and are not repeated here; the beneficial effects brought by the sine coil 3221 are basically the same as those brought by the cosine coil 400, and are not repeated here.

[0099] More specifically, the cosine coil 400 is the same as the cosine coil 200 and can generate a cosine-sine envelope waveform signal. The sine coil 3221 is the same as the sine coil 1221 and can generate a sine-cosine envelope waveform signal.

[0100] like Figure 13As shown, in this embodiment, exemplarily, the first section 4111 includes a first portion 4111a and a second portion 4111b extending along the second direction 303 and a third portion 4111c extending along the direction of the preset straight line 301, that is, the first portion 4111a and the second portion 4111b both extend along a straight line, and the first portion 4111a and the second portion 4111b are basically parallel.

[0101] The first portion 4111a, the third portion 4111c, and the second portion 4111b are sequentially connected; the structure of the second segment 4112 is consistent with that of the first segment 4111. Through this arrangement, the projection M3 of the sensing area of the first segment 4111 can be made substantially rectangular, and the projection M4 of the sensing area of the second segment 4112 can be made substantially rectangular. Furthermore, the projections of the sensing areas of the first segment 4111 and the second segment 4112 are centrally symmetrical about their connection point.

[0102] like Figure 14 As shown, for example, the first section 4111 includes a first portion 4111a that forms an acute angle with the second direction 303, a second portion 4111b that forms an acute angle with the second direction 303, and a third portion 4111c that extends along the predetermined straight line 301. That is, the first portion 4111a and the second portion 4111b both extend along a straight line, and the first portion 4111a and the second portion 4111b form an angle therebetween. It should be noted that the acute angle formed by the first portion 4111a and the second direction 303 can be the same as the acute angle formed by the second portion 4111b and the second direction 303, or the acute angle formed by the first portion 4111a and the second direction 303 can be different from the acute angle formed by the second portion 4111b and the second direction 303. That is, the positions of the first portion 4111a and the second portion 4111b can be adjusted according to actual conditions.

[0103] The first portion 4111a, the third portion 4111c, and the second portion 4111b are connected in sequence; the structure of the second segment 4112 is consistent with that of the first segment 4111. Through the above arrangement, the projection M3 of the sensing area of the first segment 4111 can be substantially trapezoidal, and the projection M4 of the sensing area of the second segment 4112 can be substantially trapezoidal. Furthermore, the projections of the sensing areas of the first segment 4111 and the second segment 4112 are centrally symmetrical about their connection point.

[0104] It should be noted that in the above two embodiments, the first section 4111 also includes the same first transition portion 4111d as in the previous embodiment. The first transition portion 4111d has the same structure and effect as the first transition portion 2111d in the previous embodiment, and will not be described in detail here.

[0105] like Figure 15 As shown, for example, the first section 4111 includes a first portion 4111a that forms an acute angle with the second direction 303 and a second portion 4111b that forms an acute angle with the second direction 303. That is, the first portion 4111a and the second portion 4111b both extend along a straight line, and the first portion 4111a and the second portion 4111b form an angle. It should be noted that the acute angle formed by the first portion 4111a and the second direction 303 can be equal to the acute angle formed by the second portion 4111b and the second direction 303, or the acute angle formed by the first portion 4111a and the second direction 303 can be different from the acute angle formed by the second portion 4111b and the second direction 303. That is, the positions of the first portion 4111a and the second portion 4111b can be adjusted according to actual conditions.

[0106] The first portion 4111a and the second portion 4111b are connected, and the structure of the second segment 4112 is consistent with that of the first segment 4111. Through this arrangement, the projection M3 of the sensing area of the first segment 4111 is substantially triangular, and the projection M4 of the sensing area of the second segment 4112 is substantially triangular. Furthermore, the projection M4 of the sensing area of the first segment 4111 and the second segment 4112 are centrally symmetrical about their connection point.

[0107] It should be noted that, in the above embodiment, the first section 4111 further includes the same second transition portion 4111e as in the previous embodiment. The second transition portion 4111e has the same structure and effect as the second transition portion 2111e in the previous embodiment, and will not be described in detail here.

[0108] It should be understood that those skilled in the art can make improvements or changes based on the above description, and all such improvements and changes should fall within the scope of protection of the claims appended to this application.

Claims

1. An eddy current sensor, characterized in that: include: The rotor comprises a yoke and a plurality of teeth, the yoke being annular in structure, each of the teeth extending radially along the yoke, the plurality of teeth being evenly distributed on the outer circumferential surface of the yoke, a tooth slot being formed between two adjacent teeth, and the width of the tooth slot being consistent with the width of the tooth along the circumference of the yoke and both being defined as a preset width; A coil assembly is located on one side of the rotor along the axial direction of the yoke, and the coil assembly includes: circuit boards; A receiving coil, comprising a cosine coil and a sine coil mounted on the circuit board, the cosine coil comprising a first coil and a second coil, the first coil comprising a plurality of sequentially connected coil segments, each comprising a first segment and a second segment, the width of the first segment and the width of the second segment along the circumference of the yoke both being the preset width, defining a cylindrical surface coaxial with the yoke and passing through a connection point between the first segment and the second segment, the first segment and the second segment being located on either side of the cylindrical surface, the diameter of the yoke passing through the connection point being defined as a preset diameter, the first segment and the second segment being located on either side of the preset diameter, the first segment and the second segment each being composed of at least two straight-line extending conductors; the second coil having the same structure as the first coil, axially overlapping the first coil when the second coil moves along the circumference of the yoke by a distance of the preset width; the sine coil having the same structure as the cosine coil, axially overlapping the cosine coil when the sine coil moves along the circumference of the yoke by a distance half of the preset width; an excitation coil, the excitation coil being mounted on the circuit board and arranged around the receiving coil; The first section includes a first part, a second part, a third part and a first transition part. The first part, the third part and the second part are connected in sequence. The first transition part extends along a straight line. The first transition part is connected between the first part and the third part. The first transition part makes the first part and the third part satisfy a first arrangement method; and / or the first transition part is connected between the second part and the third part. The first transition part makes the second part and the third part satisfy a second arrangement method.

2. The eddy current sensor according to claim 1, characterized in that The cosine coil can generate a sine envelope waveform signal, and the sine coil can generate a cosine envelope waveform signal.

3. The eddy current sensor according to claim 1, characterized in that The first portion and the second portion both extend radially along the yoke, and the third portion extends perpendicularly to the radial direction of the yoke; the structure of the second section is substantially consistent with that of the first section.

4. The eddy current sensor according to claim 1, characterized in that The first portion forms an acute angle with the radial direction of the yoke, the second portion forms an acute angle with the radial direction of the yoke, and the third portion extends perpendicularly to the radial direction of the yoke; the structure of the second section is basically consistent with that of the first section.

5. The eddy current sensor according to claim 1, characterized in that: The circuit board includes an upper layer and a lower layer distributed axially along the yoke, and the connection point of the first segment and the second segment is defined as a preset point. The coil segment includes an upper segment installed on the upper layer and a lower segment installed on the lower layer. The first segment includes a first upper sub-segment with a distance from zero to one-half of the preset width from the preset point and a first lower segment with a distance from one-half of the preset width to the preset width from the preset point. The second segment includes a second upper sub-segment with a distance from zero to one-half of the preset width from the preset point and a second lower sub-segment with a distance from one-half of the preset width to the preset width from the preset point. The first upper sub-segment is connected to the second upper sub-segment. The upper segment includes the first upper sub-segment and the second upper sub-segment, and the lower segment includes the first lower sub-segment and the second lower sub-segment.

6. An eddy current sensor, characterized in that: include: The rotor comprises a yoke and a plurality of teeth, the yoke being annular in structure, each of the teeth extending radially along the yoke, the plurality of teeth being evenly distributed on the outer circumferential surface of the yoke, a tooth slot being formed between two adjacent teeth, and the width of the tooth slot being consistent with the width of the tooth along the circumference of the yoke and both being defined as a preset width; A coil assembly is located on one side of the rotor along the axial direction of the yoke, and the coil assembly includes: circuit boards; A receiving coil, comprising a cosine coil and a sine coil mounted on the circuit board, the cosine coil comprising a first coil and a second coil, the first coil comprising a plurality of sequentially connected coil segments, each comprising a first segment and a second segment, the width of the first segment and the width of the second segment along the circumference of the yoke both being the preset width, defining a cylindrical surface coaxial with the yoke and passing through a connection point between the first segment and the second segment, the first segment and the second segment being located on either side of the cylindrical surface, the diameter of the yoke passing through the connection point being defined as a preset diameter, the first segment and the second segment being located on either side of the preset diameter, the first segment and the second segment each being composed of at least two straight-line extending conductors; the second coil having the same structure as the first coil, axially overlapping the first coil when the second coil moves along the circumference of the yoke by a distance of the preset width; the sine coil having the same structure as the cosine coil, axially overlapping the cosine coil when the sine coil moves along the circumference of the yoke by a distance half of the preset width; an excitation coil, the excitation coil being mounted on the circuit board and arranged around the receiving coil; The first section includes a first part, a second part and a second transition part, the first part and the second part are connected, the second transition part is connected to the first part and the second part, and the second transition part makes the angle between the first part and the second part meet the preset angle.

7. The eddy current sensor according to claim 6, characterized in that The first portion forms an acute angle with the yoke in the radial direction, and the second portion forms an acute angle with the yoke in the radial direction; the structure of the second section is substantially consistent with that of the first section.

8. An eddy current sensor, characterized in that: include: A mover, the mover comprising a plurality of second teeth, the plurality of second teeth being evenly arranged along a preset straight line, a second tooth groove being formed between two adjacent second teeth, and a width of the second tooth groove being consistent with a width of the second tooth along the preset straight line and both being defined as a second width; a coil assembly, the coil assembly being located on one side of the plurality of second teeth along a first direction, the first direction being perpendicular to the preset straight line direction, the coil assembly comprising: circuit boards; A receiving coil, the receiving coil comprising a cosine coil and a sine coil mounted on the circuit board, the cosine coil comprising a first coil and a second coil, the first coil comprising a plurality of sequentially connected coil segments, each of the coil segments comprising a first segment and a second segment, the width of the first segment and the width of the second segment both being the second width along the preset straight line direction, the first segment and the second segment being centrally symmetrical about their connection point, the first segment and the second segment each being composed of at least two conductive wires extending along a straight line direction; the second coil having the same structure as the first coil, and when the second coil moves along the preset straight line direction by a distance of the second width, the second coil overlaps with the first coil along the first direction; the sine coil having the same structure as the cosine coil, and when the sine coil moves along the preset straight line direction by a distance of half the second width, the sine coil overlaps with the cosine coil along the first direction; an excitation coil, the excitation coil being mounted on the circuit board and arranged around the receiving coil; The first section includes a first part, a second part, a third part and a first transition part. The first part, the third part and the second part are connected in sequence. The first transition part extends along a straight line. The first transition part is connected between the first part and the third part. The first transition part makes the first part and the third part satisfy a first arrangement method; and / or the first transition part is connected between the second part and the third part. The first transition part makes the second part and the third part satisfy a second arrangement method.

9. The eddy current sensor according to claim 8, characterized in that: The first portion and the second portion both extend along the second direction, and the third portion extends along the preset straight line direction; The second direction is perpendicular to the first direction and perpendicular to the preset straight line direction; Alternatively, the first portion forms an acute angle with the second direction, the second portion forms an acute angle with the second direction, and the third portion extends along the preset straight line direction; The structure of the second section is consistent with that of the first section.

10. An eddy current sensor, characterized in that: include: A mover, the mover comprising a plurality of second teeth, the plurality of second teeth being evenly arranged along a preset straight line, a second tooth groove being formed between two adjacent second teeth, and a width of the second tooth groove being consistent with a width of the second tooth along the preset straight line and both being defined as a second width; a coil assembly, the coil assembly being located on one side of the plurality of second teeth along a first direction, the first direction being perpendicular to the preset straight line direction, the coil assembly comprising: circuit boards; A receiving coil, the receiving coil comprising a cosine coil and a sine coil mounted on the circuit board, the cosine coil comprising a first coil and a second coil, the first coil comprising a plurality of sequentially connected coil segments, each of the coil segments comprising a first segment and a second segment, the width of the first segment and the width of the second segment both being the second width along the preset straight line direction, the first segment and the second segment being centrally symmetrical about their connection point, the first segment and the second segment each being composed of at least two conductive wires extending along a straight line direction; the second coil having the same structure as the first coil, and when the second coil moves along the preset straight line direction by a distance of the second width, the second coil overlaps with the first coil along the first direction; the sine coil having the same structure as the cosine coil, and when the sine coil moves along the preset straight line direction by a distance of half the second width, the sine coil overlaps with the cosine coil along the first direction; an excitation coil, the excitation coil being mounted on the circuit board and arranged around the receiving coil; The first section includes a first part, a second part and a second transition part, the first part and the second part are connected, the second transition part is connected to the first part and the second part, and the second transition part makes the angle between the first part and the second part meet the preset angle.

11. The eddy current sensor according to claim 10, characterized in that: The first portion forms an acute angle with the second direction, and the second portion forms an acute angle with the second direction; the second direction is perpendicular to the first direction and perpendicular to the preset straight line direction; The structure of the second section is substantially the same as that of the first section.

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