Magnetic induction displacement encoder, displacement detection mechanism and displacement detection method

Abstract

The present invention relates to the field of displacement measurement technology, and in particular to a magnetic induction displacement encoder, a displacement detection mechanism and a displacement detection method. The magnetic induction displacement encoder comprises: a toothed mechanism, which comprises a base, a main tooth portion and a vernier tooth portion; a magnetic induction head, which comprises a detection unit, which is arranged on the side of the induction tooth facing away from the base, and a detection gap is formed between the detection unit and the induction tooth; a magnetic mechanism, which is arranged on the side of the detection unit facing away from the induction tooth, and is fixed to the magnetic induction head for generating a magnetic field. The present invention generates a corresponding electrical signal through the change of the relative position of the induction teeth arranged on the main tooth portion and the vernier tooth portion, thereby realizing the detection of the position of the measured object relative to the toothed mechanism, and the structure is simple and reliable; and through the independently arranged magnetic mechanism, a strong magnetic field can be formed to reduce the interference of the external magnetic field.

Description

Technical Field

[0001] The present invention relates to the field of displacement measurement technology, and in particular to a magnetic induction displacement encoder, a displacement detection mechanism and a displacement detection method. Background Art

[0002] The existing encoder is a sensor used to detect angle, position, speed and acceleration. It is a device that compiles and converts the angular displacement or linear displacement of mechanical rotation into an electrical signal that can be used for communication, transmission and storage. It is a precision measuring device that closely combines mechanics and electronics, and is widely used in many fields such as motors, automobiles, wind power, robots, etc.

[0003] The encoder using tunnel magnetoresistance element is a magnetic induction encoder. Traditional magnetic induction encoders can be divided into relative magnetic induction encoders and absolute magnetic induction encoders based on measurement function. The relative magnetic induction encoder can also be called an incremental magnetic induction encoder.

[0004] Among them, the magnetic scale is a component of a magnetic induction encoder that is commonly used in the linear displacement measurement of industrial automation machinery. The magnetic scale is mainly composed of two parts: the magnetic scale and the magnetic head. The N (North Pole) S (South Pole)-SN-NS poles on the magnetic scale form an electromagnetic field with different orientations. During the entire stroke of the magnetic scale movement, the magnetic head senses the change of the electromagnetic field and converts this electromagnetic field change into an analog input signal or a digital signal output.

[0005] Today, active suspensions of vehicles are equipped with active shock absorbers that can adjust the height of the vehicle body according to the working conditions. The height adjustment of the vehicle body is often achieved by a linear motor. During the adjustment process, an encoder is needed to obtain the real-time relative displacement of the motor stator and mover. The stator and mover are displaced by the change in magnetic force generated by the magnetic parts, and the encoder set between the two is easily disturbed by the magnetic field, resulting in inaccurate measurement results.

[0006] Furthermore, since the magnetic field strength that the magnetic scale can generate is relatively weak, when the magnetic head is operated in an external environment with magnetic field interference, it is easy to cause the measurement accuracy of the magnetic head to decrease or even fail.

[0007] In addition, although the invention patent application with publication number CN117232554A discloses a magnetic induction linear displacement absolute encoder and its data processing method and equipment, the magnetic field density amplitude of the detection position of the magnetic induction chip of the encoder is small during the measurement process, and is easily disturbed by the external magnetic field, thereby generating a large measurement error; in order to avoid external magnetic field interference and reduce the measurement error of the magnetic induction chip, the existing encoder needs to adopt a larger magnetic mechanism to generate a stronger magnetic field, but at the same time increases the volume of the encoder, and has fewer applicable scenarios. Summary of the invention

[0008] The purpose of the present invention is to provide a magnetic induction displacement encoder that can accurately calculate the position of a measured object, avoid external magnetic field interference, and improve detection accuracy, as well as a displacement detection mechanism and a displacement detection method including the magnetic induction displacement encoder.

[0009] In order to achieve the above object, the present invention provides a magnetic induction displacement encoder, comprising:

[0010] A toothed mechanism, the toothed mechanism comprising a base, a main tooth portion, and a vernier tooth portion cooperating with the main tooth portion to affect a magnetic field, the main tooth portion and the vernier tooth portion are both arranged on the same side of the base, the main tooth portion and the vernier tooth portion both comprise a plurality of induction teeth spaced and evenly arranged along a first direction, the interval between two adjacent induction teeth of the main tooth portion is J millimeters, the interval between two adjacent induction teeth of the vernier tooth portion is K millimeters, K>J;

[0011] A magnetic induction reading head, the magnetic induction reading head comprising a detection unit, the detection unit being arranged on a side of the induction tooth facing away from the base body and forming a detection gap between the detection unit and the induction tooth;

[0012] A magnetic mechanism, which is disposed on a side of the detection unit facing away from the induction teeth and is fixed to the magnetic induction reading head to generate a magnetic field;

[0013] In which, the magnetic induction reading head can move along the first direction with the object to be measured, and the length of the detection gap has a corresponding relationship with the tooth height of the inductive tooth. The corresponding relationship enables the detection unit to generate an electrical signal for obtaining the displacement of the object to be measured according to the magnetic flux lines of the magnetic field generated by the magnetic mechanism cut by the tooth-shaped mechanism, and the length of the detection gap is the vertical distance between the detection unit and the inductive tooth.

[0014] In some embodiments of the present application, the magnetic mechanism is a magnetic steel body, and the magnetic steel body has a magnetic field compensation portion for uniform magnetic field distribution.

[0015] In some embodiments of the present application, the magnetic field compensation portion is a groove and a protrusion formed by a side of the magnetic steel body facing toward or away from the toothed mechanism, and the protrusion is arranged on the periphery of the groove.

[0016] In some embodiments of the present application, the protrusions are respectively formed on both side edges of the groove along the first direction or the second direction, and the first direction is perpendicular to the second direction.

[0017] In some embodiments of the present application, the protrusions are arranged circumferentially along the edge of the groove.

[0018] In some embodiments of the present application, a side surface of the protrusion close to the groove is inclined upward and extends outward from the bottom surface of the groove.

[0019] In some embodiments of the present application, the groove depth of the groove is h mm, the groove width of the groove is d mm, and the distance between the magnetic steel body and the induction tooth is s mm, then:

[0020]

[0021] Among them, h>0, d>0, s>0.

[0022] In some embodiments of the present application, the bottom surface of the groove is smoothly transitionally connected to the plane connected to its periphery.

[0023] In some embodiments of the present application, the main tooth portion and the vernier tooth portion have the same length in the first direction.

[0024] In some embodiments of the present application, the number of the inductive teeth of the main tooth portion is N, and the number of the inductive teeth of the vernier tooth portion is M;

[0025] When NM=1, the magnetic induction displacement encoder is an absolute magnetic induction displacement encoder;

[0026] When NM≥2, the magnetic induction displacement encoder is a relative magnetic induction displacement encoder.

[0027] In some embodiments of the present application, the base, the main tooth portion and the vernier tooth portion are integrally formed.

[0028] In some embodiments of the present application, the induction teeth are involute teeth.

[0029] In some embodiments of the present application, the toothed mechanism is a linear rack.

[0030] In some embodiments of the present application, a circular gear or an end-face toothed chainring.

[0031] In some embodiments of the present application, the tooth height of the sensing tooth is H mm, the length of the detection gap is C mm, 0.8≤H / C≤5, wherein 0.3≤C≤1.2.

[0032] In some embodiments of the present application, the thickness of the substrate is T millimeters, 0.5≤T≤5.

[0033] In some embodiments of the present application, the magnetic induction read head further includes a shell having a housing formed therein, the detection unit and the magnetic mechanism are both disposed in the housing cavity, and the magnetic mechanism is disposed on a side of the detection unit facing away from the toothed mechanism.

[0034] In some embodiments of the present application, the shell is made of non-magnetic material.

[0035] In some embodiments of the present application, a detection window communicating with the accommodating cavity is formed on a side of the shell facing the toothed mechanism, and the detection unit is disposed opposite to the toothed mechanism through the detection window.

[0036] In some embodiments of the present application, the housing is provided with an opening connected to the accommodating cavity on a side facing away from the toothed mechanism, and the opening cover is provided with a cover body.

[0037] In some embodiments of the present application, the cover is made of magnetic conductive material.

[0038] In some embodiments of the present application, a magnetic conductive sheet is provided between the magnetic mechanism and the detection unit.

[0039] In some embodiments of the present application, two side surfaces of the magnetic conductive sheet are respectively attached to the detection unit and the magnetic mechanism.

[0040] In some embodiments of the present application, the thickness of the magnetic conductive sheet is A millimeters, 0.1≤A≤1.

[0041] In some embodiments of the present application, a projection of the magnetic conductive sheet along a direction in which the toothed mechanism approaches the magnetic mechanism coincides with a side surface of the magnetic mechanism facing the toothed mechanism.

[0042] In some embodiments of the present application, a magnetic shielding mechanism made of a high magnetic permeability material is further included. Along the first direction, at least one side of the toothed mechanism is provided with the magnetic shielding mechanism, and the magnetic shielding mechanism is extended along the first direction.

[0043] In some embodiments of the present application, the magnetic shielding mechanism is provided on both sides of the toothed mechanism along the first direction.

[0044] In some embodiments of the present application, the magnetic field strength generated by the magnetic mechanism is B millitesla, 10≤B≤500.

[0045] Based on the above invention purpose, the present invention also provides a displacement detection mechanism, which includes the above magnetic induction displacement encoder.

[0046] Based on the above invention purpose, the present invention also provides a displacement detection method based on the above displacement detection mechanism, comprising the following steps:

[0047] S1: According to the toothed mechanism cutting the induced magnetic lines, a corresponding number of first sine-cosine orthogonal differential signals are generated, and the DC offset error, amplitude error and orthogonal phase error of the first sine-cosine orthogonal differential signal are corrected and compensated in real time to obtain a second sine-cosine orthogonal differential signal;

[0048] S2: Generate relative position values ​​of the main tooth portion and the vernier tooth portion relative to the power-on moment according to the second sine-cosine orthogonal differential signal;

[0049] S3: Analyze the phase and phase difference of the second sine-cosine orthogonal differential signal according to the vernier solution principle, and calculate the current displacement position of the measured object.

[0050] The implementation of the embodiments of the present invention has the following technical effects:

[0051] An independent magnetic mechanism is provided, and a strong magnetic field is generated by the magnetic mechanism. When the magnetic induction reading head moves with the measured object along the first direction in which the plurality of induction teeth of the main tooth portion and the vernier tooth portion are arranged, the magnetic field generated by the magnetic mechanism is affected. Since the distance J between two adjacent induction teeth of the main tooth portion and the distance K between two adjacent induction teeth of the vernier tooth portion are different, when the main tooth portion and the vernier tooth portion are arranged relative to each other, the relative positions of the induction teeth of the main tooth portion and the induction teeth of the vernier tooth portion are gradually offset along the first direction, so that the detection unit can detect the different magnetic field strengths generated when the magnetic mechanism is at different positions relative to the main tooth portion and the vernier tooth portion, and generate corresponding electrical signals, thereby calculating the position of the magnetic induction reading head in the tooth mechanism;

[0052] Furthermore, since an independent magnetic mechanism can be provided to generate a strong magnetic field, when the detection unit detects the change in the magnetic field of the magnetic mechanism relative to the toothed mechanism during movement, the interference of the external magnetic field can be reduced, thereby improving the reliability of the detection by the detection unit, and furthermore, the position of the object to be detected connected to the magnetic induction read head relative to the toothed mechanism can be more accurately calculated;

[0053] Finally, by making the length of the detection gap correspond to the tooth height of the induction tooth, the magnetic field density amplitude at the detection position of the detection unit can be made relatively large, thereby improving the accuracy of the detection unit in obtaining the magnetic field changes when the tooth-shaped structure cuts the magnetic flux lines of the magnetic field generated by the magnetic mechanism, reducing the possibility of external magnetic field interference and measurement errors; and can reduce the loss of magnetic field strength generated by the magnetic mechanism and reduce the volume of the magnetic mechanism used, which is suitable for more scenarios with higher requirements on the encoder usage volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] The present invention will be described in more detail below with the aid of the accompanying drawings. Regardless of a specific combination of technical features, the technical features shown in the accompanying drawings and / or described below are generally technical features of the present invention and improve the present invention accordingly.

[0055] It should be noted that in different drawings, the same reference numerals denote the same or substantially the same components.

[0056] Figure 1 is a schematic structural diagram of a magnetic induction displacement encoder according to a preferred embodiment of the present invention;

[0057] Figure 2 is a top view of a magnetic induction displacement encoder according to a preferred embodiment of the present invention;

[0058] Figure 3 is a schematic structural diagram of a magnetic induction read head according to a preferred embodiment of the present invention;

[0059] Figure 4 It is an exploded schematic diagram of a magnetic induction read head, a magnetic mechanism, and a magnetic conductive sheet according to a preferred embodiment of the present invention;

[0060] Figure 5 yes Figure 2 The cross-sectional view at Ⅰ-Ⅰ in the middle;

[0061] Figure 6 yes Figure 5 The enlarged schematic diagram of the middle II;

[0062] Figure 7 is a partially enlarged cross-sectional view of a toothed mechanism of a preferred embodiment of the present invention;

[0063] Figure 8 is a schematic structural diagram of a housing in a preferred embodiment of the present invention;

[0064] Fig. 9 is a structural schematic diagram of a cover body according to a preferred embodiment of the present invention;

[0065] Fig.10 is a structural schematic diagram of a magnetic mechanism in a preferred embodiment of the present invention;

[0066] Fig.11 is a right side view of the magnetic mechanism of the preferred embodiment of the present invention;

[0067] Fig.12 is a top view of a magnetic mechanism of a preferred embodiment of the present invention;

[0068] Fig.13 It is the strength curve of the magnetic field generated by the magnetic steel body in the Y direction in the prior art;

[0069] Fig.14 It is the intensity curve of the magnetic field in the Y direction generated by the magnetic steel body of the preferred embodiment of the present invention.

[0070] Description of reference numerals:

[0071] 1. Toothed mechanism, 11. Base, 12. Main tooth, 13. Vernier tooth, 14. Induction tooth

[0072] 2. Magnetic induction reader, 21. Detection unit, 211. Magnetic induction chip, 212. Interface circuit, 22. Shell, 221. Accommodation cavity, 222. Detection window, 223. Hook groove, 224. Positioning groove, 225. Wire hole, 23. Cover, 231. Hook;

[0073] 3. magnetic mechanism, 31. magnetic steel body, 32. groove, 33. protrusion;

[0074] 4. Magnetic sheet;

[0075] 5. Magnetic shielding mechanism. DETAILED DESCRIPTION

[0076] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the invention but are not intended to limit the scope of the present invention.

[0077] First, it should be noted that the top, bottom, upward, downward and other directions mentioned in this article are defined relative to the directions in the various drawings. They are relative concepts and can therefore be changed according to different positions and different usage conditions, so these or other directions should not be understood as restrictive terms. At the same time, the term "comprising" does not exclude other elements or steps, and "a" or "an" does not exclude plural numbers.

[0078] In addition, it should be pointed out that any single technical feature described or implied in the embodiments of this document, or any single technical feature shown or implied in the drawings, can still be combined between these technical features (or their equivalents) to obtain other embodiments of the present application that are not directly mentioned in this document.

[0079] In addition, it should be understood that the terms "first", "second", etc. are used herein to describe various information, but such information should not be limited to these terms, and these terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of this application, "first" information may also be referred to as "second" information, and similarly, "second" information may also be referred to as "first" information.

[0080] In this embodiment, a displacement detection mechanism is provided, wherein the displacement detection mechanism includes a magnetic induction displacement encoder. Figure 1 and Figure 2In this embodiment, a magnetic induction displacement encoder is provided, comprising: a toothed mechanism 1, a magnetic induction reader 2 and a magnetic mechanism 3. The displacement detection mechanism in this embodiment is used for the active suspension of the vehicle, and can be used to detect the relative displacement and relative position between the mover and stator of the linear motor when the stator and mover of the linear motor are relatively displaced by fixing the toothed mechanism 1 to the stator of the linear motor in the active suspension and fixing the magnetic induction reader 2 to the mover in the linear motor.

[0081] Further, the toothed mechanism 1 includes a base 11, a main tooth portion 12 and a vernier tooth portion 13, the main tooth portion 12 and the vernier tooth portion 13 are both arranged on the same side of the base 11, the main tooth portion 12 and the vernier tooth portion 13 each include a plurality of sensing teeth 14 spaced and evenly arranged along a first direction, the interval between two adjacent sensing teeth 14 of the main tooth portion 12 is J mm, the interval between two adjacent sensing teeth 14 of the vernier tooth portion 13 is K mm, K>J;

[0082] The magnetic induction reader 2 includes a detection unit 21, which is arranged on the side of the sensing tooth 14 facing away from the base 11 and forms a detection gap between the detection unit 21 and the sensing tooth 14; the magnetic mechanism 3 is arranged on the side of the detection unit 21 facing away from the sensing tooth 14 and is fixed to the magnetic induction reader 2 for generating a magnetic field.

[0083] Among them, the magnetic induction head 2 can move along the first direction with the object to be measured (the mover of the linear motor in the vehicle's active suspension), and the detection unit 21 generates a corresponding electrical signal according to the magnetic flux lines of the magnetic field generated by the toothed mechanism 1 cutting the magnetic mechanism 3 to obtain the displacement of the object to be measured; specifically, the magnetic induction head 2 can be fixedly connected to the object to be measured by bolting, welding or bonding.

[0084] In this way, the magnetic induction displacement encoder in this embodiment is provided with an independent magnetic mechanism 3, and the magnetic mechanism 3 can generate a strong magnetic field. When the magnetic induction head 2 moves with the measured object along the first direction in which the plurality of induction teeth 14 of the main tooth portion 12 and the vernier tooth portion 13 are arranged, the magnetic field generated by the magnetic mechanism 3 is affected, and because the distance J between two adjacent induction teeth of the main tooth portion 12 and the distance K between two adjacent induction teeth 14 of the vernier tooth portion 13 are different, therefore, when the main tooth portion 12 and the vernier tooth portion 13 are arranged relative to each other, the relative positions of the induction teeth 14 of the main tooth portion 12 and the induction teeth 14 of the vernier tooth portion 13 are gradually offset along the first direction, so that the detection unit 21 can detect the different magnetic field strengths generated when the magnetic mechanism 3 is at different positions relative to the main tooth portion 12 and the vernier tooth portion 13, and generate corresponding electrical signals, thereby calculating the position of the magnetic induction head 2 in the tooth mechanism 1;

[0085] Furthermore, since an independent magnetic mechanism 3 can be set up to generate a strong magnetic field, when the detection unit 21 detects the changes in the magnetic field of the magnetic mechanism 3 during the movement of the toothed mechanism 1, the interference of the external magnetic field can be reduced, thereby improving the reliability of the detection of the detection unit 21, and further more accurately calculating the position of the object to be measured connected to the magnetic induction reader 2 relative to the toothed mechanism 1.

[0086] refer to Figure 1 , Figure 2 , Figure 5 and Figure 7 Furthermore, in the present embodiment, the toothed mechanism 1 is a linear rack, wherein the first direction in the present embodiment is the length direction of the linear rack. Specifically, the inductive teeth 14 of the main tooth portion 12 and the vernier tooth portion 13 in the present embodiment are all involute teeth. It should be noted that the linear rack is a special gear with an infinite gear radius. The "pitch circle" of the rack becomes a pitch line, which is a straight line. Because the standard gear pressure angle is 20°, the tooth profile curvature radius at the rack "pitch circle" is infinite, so the tooth profile presents a trapezoidal shape.

[0087] In other embodiments, the toothed mechanism 1 may be a circular gear or an end-face toothed chainring.

[0088] refer to Figure 2 and Figure 3 Specifically, the magnetic induction displacement encoder in this embodiment is an absolute magnetic induction displacement encoder, wherein the detection unit 21 includes a magnetic induction chip 211 and an interface circuit 212, the magnetic induction chip 211 is electrically connected to the interface circuit 212, and is electrically connected to the external circuit through the interface circuit 212; specifically, the magnetic induction chip 211 of this embodiment adopts the iC-MU series magnetic off-axis absolute position encoder chip of the German iC-Haus company, model iC-MU200.

[0089] In order to save the space for setting the toothed mechanism 1, the lengths of the main tooth portion 12 and the vernier tooth portion 13 in the first direction are equal, and the number of the inductive teeth 14 of the main tooth portion 12 is N, and the number of the inductive teeth 14 of the vernier tooth portion 13 is M, where M<N. Since the present embodiment is an absolute magnetic induction displacement encoder, the relationship between the number N of the inductive teeth 14 of the main tooth portion 12 and the number M of the inductive teeth 14 of the vernier tooth portion 13 is: NM=1, so that the main tooth portion 12 and the vernier tooth portion 13 are mirror-symmetrically arranged except for the two inductive teeth 14 at both ends in the length direction, and along the first direction, the inductive teeth 14 of the main tooth portion 12 and the vernier tooth portion 13 are gradually offset and shifted, and the offset distances are all different, so that when the magnetic field generated by the magnetic mechanism 3 corresponds to any two inductive teeth 14 on both sides of the first direction, the magnetic field strength detected by the detection unit 21 is different, and a unique electrical signal can be generated accordingly to determine the position of the magnetic induction reading head 2 in the toothed mechanism 1.

[0090] In some other embodiments, the magnetic induction displacement encoder is a relative magnetic induction displacement encoder, NM≥2; specifically, when NM=2, the magnetic induction displacement encoder is a dual-cycle displacement encoder; when NM=3, the magnetic induction displacement encoder is a triple-cycle displacement encoder; and so on.

[0091] For further reference, Figure 1 In this embodiment, the base 11, the main tooth portion 12 and the vernier tooth portion 13 are integrally formed. Specifically, the base 11, the main tooth portion 12 and the vernier tooth portion 13 in this embodiment are integrally formed by metal injection molding; on the one hand, the overall stability and reliability of the toothed mechanism 1 can be improved; on the other hand, the base 11, the main tooth portion 12 and the vernier tooth portion 13 can be molded at one time to ensure the accuracy of the relative position between the main tooth portion 12 and the sensing tooth 14 of the vernier tooth portion 13, avoid errors that may occur during the assembly process, and improve the reliability of detection.

[0092] In other embodiments, the base 11 , the main tooth portion 12 and the cursor tooth portion 13 may be integrally formed by using a molding technique.

[0093] In order to improve the measurement accuracy and reduce the measurement error, the length of the detection gap is made to correspond to the tooth height of the induction tooth 14, and the magnetic field strength of the detection position of the detection unit 21 is increased. The length of the detection gap, that is, the vertical distance between the detection unit 21 and the induction tooth 14, is referred to Figure 1 and Figure 7 , the tooth height of the inductive tooth 14 is H mm, the vertical distance between the detection unit 21 and the inductive tooth 14 is C mm, and the following relationship is satisfied: 0.8≤H / C≤5, and the directions of the magnetic field generated by the magnetic mechanism in this embodiment are respectively the X direction, the Y direction and the Z direction, wherein, since the detection unit 21 can simultaneously scan the inductive teeth 14 of the main tooth portion 12 and the vernier tooth portion 13, therefore, the vertical distance C mm between the detection unit 21 and the inductive tooth 14 is the vertical distance between the detection unit 21 and the inductive tooth 14 of the main tooth portion 12 or the vertical distance between the detection unit 21 and the inductive tooth 14 of the vernier tooth portion 13, wherein the X direction is the above-mentioned first direction, the Y direction is perpendicular to the X direction, and the toothed mechanism 1, the detection unit 21 and the magnetic mechanism 3 are arranged in sequence along the Z direction;

[0094] Table 1

[0095]

[0096] As can be seen from Table 1, when the tooth height H of the induction tooth 14 and the distance C between the detection unit 21 and the induction tooth 14 meet 0.8≤H / C, under the action of the same magnetic mechanism 3, the magnetic field density amplitude of the magnetic field generated by the magnetic mechanism 3 in the Y direction where the detection unit 21 is located is relatively high, and has a larger increase relative to H / C<1, so that the modulation of the magnetic field by the magnetic induction chip 211 when the magnetic induction head 2 moves relative to the toothed mechanism 1 can be enhanced, thereby increasing the amplitude of the sine-cosine orthogonal differential signal, and can effectively increase the ratio of the intensity of the received useful signal to the intensity of the received interference signal, thereby reducing the detection error. Therefore, when the magnetic mechanism 3 of the same volume is used, the spatial structure of the magnetic induction encoder can be optimized through the above relationship, so that the space utilization rate of the equipment assembled therein is higher and better performance is exerted. On the premise that the requirements of the magnetic field density amplitude in the Y direction have been met, considering the problem of space occupation and ensuring a higher average value of the magnetic field density in the Y direction, it is set to H / C≤5.

[0097] In addition, when 0.3≤C≤1.2, the magnetic mechanism 3 can be set as close to the tooth mechanism 1 as possible, so as to ensure the magnetic field strength at the position of the tooth mechanism 1, and avoid the magnetic field generated by the magnetic mechanism 3 being disturbed by the external magnetic field when acting on the tooth mechanism 1, thereby affecting the measurement accuracy, thereby achieving higher detection accuracy and smaller measurement error.

[0098] Furthermore, in order to avoid interference from the external magnetic field and improve the measurement accuracy of the detection unit 21, the magnetic field strength generated on the surface of the magnetic mechanism 3 is B millitesla (mT), 10≤B≤500; specifically, in this embodiment, the magnetic field strength B generated on the surface of the magnetic mechanism 3 is 50mT. The tooth height H of the induction tooth 14 in this embodiment is 1.4 mm, and the vertical distance C between the detection unit 21 and the induction tooth 14 is 0.4 mm, satisfying the following relationship: H / C=3.5. In other embodiments, the tooth height H of the sensing tooth 14 may be 1.8 mm, and the vertical distance C between the detection unit 21 and the sensing tooth 14 may be 0.5 mm; the tooth height H of the sensing tooth 14 may be 1.4 mm, and the vertical distance C between the detection unit 21 and the sensing tooth 14 may be 0.6 mm; the tooth height H of the sensing tooth 14 may be 0.8 mm, and the vertical distance C between the detection unit 21 and the sensing tooth 14 may be 0.7 mm; the tooth height H of the sensing tooth 14 may be 2 mm, and the vertical distance C between the detection unit 21 and the sensing tooth 14 may be 0.4 mm.

[0099] Furthermore, the detection unit 21 in this embodiment has a detection plane, which is parallel to the tooth top plane of the inductive teeth 14 of the main tooth portion 12 and the vernier tooth portion 13, so that when the magnetic induction reading head 2 moves along the first direction, the magnetic field uniformity of the position of the detection plane along the Y direction is better, which helps to reduce the measurement error; thus, in this embodiment, the detection plane is the side of the detection unit 21 facing the toothed mechanism 1, that is, the vertical distance C between the detection unit 21 and the inductive teeth 14, which is the vertical distance between the detection plane and the inductive teeth 14 of the main tooth portion 12 or the vernier tooth portion 13.

[0100] For further reference, Figure 7 , along the first direction, in this embodiment, the tooth spacing between two adjacent inductive teeth 14 is L, the tooth root spacing between two adjacent inductive teeth 14 is L1, and the tooth top width of the inductive teeth 14 is L2, wherein, L1:L2:L =1:1:(2.8-3.2), thereby meeting the machining accuracy requirements and ensuring the resolution and sensitivity of the detection unit to obtain the magnetic field change when the relative toothed mechanism 1 moves; specifically, since the relationship between the number N of the inductive teeth 14 of the main tooth portion 12 and the number M of the inductive teeth 14 of the vernier tooth portion 13 is: NM=1, since the magnetic induction chip 211 of this embodiment adopts the iC-MU series magnetic off-axis absolute position encoder chip of the German iC-Haus company, model iC-MU200, therefore, the number N of the inductive teeth 14 of the main tooth portion 12 is set to 32, the number M of the inductive teeth 14 of the vernier tooth portion 13 is set to 31, and the main tooth portion 12 along the first direction The distance between the two induction teeth 14 at both ends is the same as the distance between the two induction teeth 14 at both ends of the vernier tooth portion 13 along the first direction, that is, the distance between two adjacent induction teeth 14 of the main tooth portion 12 is smaller than the distance between two adjacent induction teeth 14 of the vernier tooth portion 13. Furthermore, in the present embodiment, the tooth spacing L of the main tooth portion 12 is 4±0.03 mm, the tooth top width L2 is 1.345±0.03 mm, and the tooth root spacing L1 is 1.345±0.03 mm; the tooth spacing L of the vernier tooth portion 13 is 4.129±0.03 mm, the tooth top width L2 is 1.345±0.03 mm, and the tooth root spacing L1 is 1.345±0.03 mm.

[0101] The thickness of the substrate 11 in this embodiment is T mm, 0.5≤T≤5. On the one hand, the substrate 11 of this thickness can form a good shielding effect of the external magnetic field, reduce the influence of the external magnetic field on the magnetic field generated by the magnetic mechanism 3, thereby improving the detection accuracy of the detection unit 21; on the other hand, the substrate 11 with a thickness less than the above thickness cannot effectively shield the external magnetic interference, thereby reducing the detection accuracy of the detection unit 21. The substrate 11 with a thickness greater than the above thickness is likely to cause the installation to occupy a larger space, thereby reducing the space utilization rate; specifically, T=1 mm in this embodiment.

[0102] For further reference, Figure 2 , Figure 8 and Fig. 9 The magnetic induction reading head 2 in this embodiment also includes a shell 22, which is provided with a screw hole. The shell 22 is fixed to the object to be measured by screws so as to move with the object to be measured. A accommodating cavity 221 is formed in the shell 22, and the detection unit 21 is arranged in the accommodating cavity 221. The magnetic mechanism 3 is arranged on the side of the detection unit 21 facing away from the tooth mechanism 1; specifically, the magnetic mechanism 3 is also arranged in the accommodating cavity 221, and is arranged close to the side of the detection unit 21 facing away from the induction tooth 14.

[0103] Among them, a magnetic conductive sheet 4 is provided between the magnetic mechanism 3 and the detection unit 21, and the magnetic mechanism 3, the magnetic conductive sheet 4 and the detection unit 21 are sequentially fitted and fixed. Specifically, since the detection unit 21 includes a magnetic induction chip 211 and an interface circuit 212, wherein the interface circuit 212 is a circuit board structure, in order to enable the magnetic induction chip 211 to better detect the changes in the magnetic field caused by the influence of the toothed mechanism 1, the magnetic induction chip 211 is installed on the side of the interface circuit 212 facing away from the magnetic mechanism 3 and arranged toward the toothed mechanism 1. Furthermore, the magnetic mechanism 3, the magnetic conductive sheet 4 and the detection unit 21 are all fixed in the accommodating cavity 221 formed by the shell 22 through epoxy resin encapsulation, so that the relative positions of the magnetic mechanism 3, the magnetic conductive sheet 4 and the detection unit 21 are fixed, thereby avoiding the decrease in detection accuracy due to relative movement; specifically, the shell 22 in this embodiment is made of non-magnetic conductive material, which can avoid the magnetic field generated by the magnetic mechanism 3 from being affected, so that the magnetic lines of force generated by the magnetic field of the magnetic mechanism 3 can penetrate the shell 22 to reach the detection unit 21.

[0104] For further reference, Figure 8 A detection window 222 connected to the accommodating cavity 221 is provided on one side of the shell 22 facing the toothed mechanism 1. The detection unit 21 is arranged opposite to the toothed mechanism 1 through the detection window 222, thereby avoiding the problem of reduced detection accuracy caused by other objects blocking the detection unit 21 and improving the detection reliability; specifically, the detection unit 21 is installed on the interface circuit 212, protrudes toward the direction of the toothed mechanism 1, and is embedded in the detection window 222, so that the detection unit 21 can be as close to the toothed mechanism 1 as possible, thereby improving the accuracy of magnetic field sensing.

[0105] In addition, the shell 22 of this embodiment is provided with an opening connected to the accommodating chamber 221 on the side facing away from the toothed mechanism 1, and the opening cover is provided with a cover body 23. The cover body 23 can be made of magnetic or non-magnetic material. Specifically, the cover body 23 in this embodiment is made of magnetic material, which can effectively block the interference of the external magnetic field from the side of the cover body 23 facing away from the accommodating chamber 221, thereby improving the stability of the magnetic field generated by the magnetic mechanism 3 and the detection accuracy of the detection unit 21.

[0106] Among them, reference Figure 8 and Fig. 9 The cover body 23 in this embodiment is fixed to the shell body 22 by a snap-fit ​​structure. Specifically, hooks 231 are respectively provided on the two opposite sides of the cover body 23 facing the side of the shell body 22. The two hooks 231 both have hook portions, and the hook portions of the two hooks 231 are arranged back to back. Hook grooves 223 are respectively provided on the two opposite side walls of the shell body 22. When the cover body 23 is covered and fixed to the shell body 22, the hooks 231 can be embedded in the hook grooves 223 and hooked on the inner wall of the hook grooves 223.

[0107] Furthermore, a positioning groove 224 is formed on the inner wall of the shell 22, and the positioning groove 224 passes through a side of the shell 22 facing the cover 23. When the cover 23 is covered on the shell 22, it can be embedded in the positioning groove 224 to improve the reliability and efficiency of the installation of the cover 23 and the shell 22.

[0108] A wire hole 225 is provided on one side wall of the housing 22, through which external wires can pass and be electrically connected to the interface circuit 212 in the housing 22, so as to realize electrical conduction and data transmission between the magnetic induction chip 211 and the interface circuit 212 and external devices.

[0109] refer to Figure 5 and Figure 6 In this embodiment, the thickness of the magnetic sheet 4 is A=0.1 mm, and the magnetic sheet 4 is made of a high magnetic permeability material, such as a silicon steel sheet material. On the one hand, it can shield the residual magnetism and stray magnetic field generated by the outside world, and prevent the detection unit 21 from being disturbed by the residual magnetism and stray magnetic field generated by the outside world; on the other hand, it can play a magnetic conductive role in the magnetic field generated by the magnetic mechanism 3. Since the magnetic lines of force are always perpendicular to the surface of the ferromagnetic material, the magnetic lines of force are NS closed and bent at the edge of the ferromagnetic material, and are equivalent to parallel magnetic fields in a parallel plane at a certain distance in the middle. Placing a magnetic sheet 4 made of a high magnetic permeability material on the side of the magnetic steel facing the toothed mechanism 1 can increase the emitting surface of the magnetic pole, increase the area of ​​the uniform parallel magnetic field, and improve the uniformity of the magnetic field within a certain sensing area, thereby improving the detection accuracy; wherein, it can be understood that the magnetic sheet 4 is a rectangular body, and the projection of the rectangular magnetic sheet 4 along the direction of the toothed mechanism 1 approaching the magnetic mechanism 3 basically coincides with the side of the magnetic mechanism 3 facing the toothed mechanism 1.

[0110] Specifically, in different embodiments, the thickness A of the magnetic conductive sheet 4 can be 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.6 mm, 0.8 mm, or 1 mm.

[0111] For further reference, Figure 1, this embodiment also includes a magnetic shielding mechanism made of a high magnetic permeability material, and a magnetic shielding mechanism 5 is provided on at least one side of the toothed mechanism 1 along the first direction; specifically, magnetic shielding mechanisms 5 are provided on both sides of the toothed mechanism 1, and the length of the magnetic shielding mechanism 5 extending along the first direction is substantially the same as that of the toothed mechanism 1, and the magnetic shielding mechanism 5 is closely attached to the two side surfaces of the toothed mechanism 1, and can shield the external stray magnetic field from entering the toothed mechanism 1, and absorb the external interfering electromagnetic waves, thereby preventing the magnetic field generated by the magnetic mechanism 3 from being interfered with by the external magnetic field, thereby solving the problem that the current magnetic scale cannot work in a strong magnetic environment; specifically, the magnetic shielding mechanism 5 can be a rectangular body made of a high magnetic permeability material, and one side surface of the magnetic shielding mechanism 5 is in contact with the side surface of the toothed mechanism 1.

[0112] Furthermore, the magnetic mechanism 3 of the present embodiment is a magnetic steel body 31. Since the magnetic field generated by the magnetic steel body 31 in the X and / or Y direction is closer to the edge, the magnetic field lines of the magnetic field gradually begin to diffuse, resulting in the magnetic field intensity generated by the magnetic steel body 31 gradually decreasing in the X and / or Y direction, generating a magnetic field bias, thereby resulting in poor uniformity of the magnetic field intensity generated by the magnetic steel body 31. Therefore, when the magnetic field intensity uniformity of the detection plane of the magnetic induction chip 211 is poor, the magnetic field bias in the X and / or Y direction cannot be eliminated, and the residual bias separation will be brought into the calculation process, resulting in a large calculation error;

[0113] Therefore, the magnetic steel body 31 has a magnetic field compensation part for uniform magnetic field distribution. Specifically, the magnetic field compensation part is a groove 32 and a protrusion 33 formed by a side of the magnetic steel body 31 facing or facing away from the toothed mechanism. The protrusion 33 is arranged on the outer periphery of the groove 32. In this way, since the thickness P of the magnetic steel body 31 with the protrusion 33 in the Z direction is greater than the thickness Q of the magnetic steel body 31 in the Z direction corresponding to the position where the groove 32 is formed by the depression, the magnetic field strength at the edge of the magnetic plane can be increased, and the magnetic field distribution can be uniform, thereby making the magnetic field strength uniform in the plane where the magnetic induction chip 211 is located better, reducing the error generated when the magnetic induction chip 211 is measured, and improving the detection accuracy; further, along the X direction (first direction) or the Y direction (second direction), the edges of the two sides of the magnetic plane are respectively provided with protrusions 33, or the protrusions 33 are arranged around the edge of the groove 32 circumferentially, so that the uniformity of the magnetic field in the X and Y directions can be improved at the same time;

[0114] Specifically, refer to Figure 4 , Figure 5 , Figure 10-12 In this embodiment, a magnetic field compensation portion is formed on the side of the magnetic steel body 31 facing away from the toothed mechanism 1 , wherein protrusions 33 are provided on both side edges of the groove 32 in the Y direction.

[0115] Furthermore, a side surface of the protrusion 33 close to the groove 32 is inclined upward and extends outward from the bottom surface of the groove 32, so that the thickness P of the magnetic body 31 corresponding to the position of the protrusion 33 can gradually increase, and the corresponding magnetic field strength also gradually increases, corresponding to the closer the magnetic body 31 is to the edge, the larger the bias amount is, and they compensate each other, further improving the uniformity of the magnetic body 31 in the Y direction or X direction of the detection plane of the magnetic sensing chip 211.

[0116] Furthermore, the bottom surface of the groove 32 is smoothly connected to the surrounding plane, thereby avoiding distortion of the periodic change signal sensed by the magnetic induction chip 211, further improving the uniformity of the magnetic field generated by the magnetic steel body 31 on the detection plane of the magnetic induction chip 211, and reducing measurement errors.

[0117] refer to Fig.13 , Fig.13 Schematic diagram of the strength of the magnetic field in the Y direction generated by the magnetic steel body without protrusions. Fig.13 It can be seen from the figure that the uniform magnetic field generated by the magnetic steel body without protrusions has a distance of approximately Fig.13 The horizontal axis value is 6.5 to 14, that is, the length of the uniform magnetic field generated by the magnetic steel body without grooves in the Y direction is 7.5;

[0118] refer to Fig.14 , Fig.14 The magnetic steel body 31 of this embodiment is Fig.14 It can be seen that the distance of the uniform magnetic field generated by the magnetic body 31 with the protrusion 33 in the Y direction in this embodiment is approximately 3-17 of the horizontal axis value, that is, the length of the uniform magnetic field generated by the magnetic body 31 with the protrusion 33 in the Y direction in this embodiment is 14, which is much larger than the area of ​​the uniform magnetic field that can be generated by the magnetic body without the protrusion 33.

[0119] Specifically, the magnetic body 31 in this embodiment is made of N40UH material, which has high magnetic properties and can form a strong magnetic field to avoid interference from the external magnetic field. The dimensions of the magnetic body 31 are: length (along the X direction) -10 mm, width (along the Y direction) -15 mm, height (along the Z direction) -4 mm.

[0120] Furthermore, in order to enable the detection unit to obtain the change of the magnetic field of the magnetic steel body 31 under the influence of the toothed mechanism 1, it is necessary to make the magnetic field generated by the magnetic steel body 31 have a good magnetic field uniformity in the Y direction of the detection plane of the magnetic induction chip 211, that is, the proportion of the uniform magnetic field in the Y direction generated by the magnetic steel body 31 in the length of the detection plane of the magnetic induction chip 211 in the Y direction, so that the detection plane of the magnetic induction chip 211 can be accommodated in the uniform magnetic field as much as possible, avoiding the measurement error of the magnetic induction chip 211. Therefore, in order to increase the length of the uniform magnetic field in the Y direction generated by the magnetic steel body 31, in this embodiment, the groove depth of the groove 32 is set to h mm, the groove width of the groove 32 is set to d mm, and the distance between the magnetic steel body 31 and the induction tooth 14 is s mm, then:

[0121]

[0122] Among them, 4>h>0, 15>d>0, s>0; preferably, 0.5≤Q / P≤0.95, Q=Ph, so that in the detection plane of the magnetic induction chip 211, the length E of the uniform magnetic field in the Y direction generated by the magnetic steel body 31 accounts for the length F of the detection plane of the magnetic induction chip 211 in the Y direction, so that the detection plane of the magnetic induction chip 211 can be in a uniform magnetic field as much as possible, which helps to reduce the measurement error of the magnetic induction chip 211.

[0123] In this embodiment, the grade of the magnetic steel body 31 is N40UH; the dimensions of the magnetic steel body 31 are 10 mm in length, 15 mm in width, and 4 mm in height; by setting grooves with different size parameters on the magnetic steel body 31 and measuring the ratio of the length of the uniform magnetic field formed in the Y direction of the detection plane of the magnetic induction chip 211 to the length of the Y direction of the detection plane of the magnetic induction chip 211, the following table can be obtained:

[0124] Table 2

[0125]

[0126] Based on Table 2, it can be seen that when the groove depth h of the groove 32, the groove width d of the groove 32, and the distance s between the magnetic steel body 31 and the induction tooth 14 satisfy the relationship:

[0127]

[0128] The uniform magnetic field length in the Y direction generated by the magnetic steel body 31 on the detection plane of the magnetic induction chip 211 accounts for more than 50% of the length in the Y direction of the detection plane of the magnetic induction chip 211. In this way, the magnetic induction chip 211 can be placed in a magnetic field environment with better uniformity as much as possible, thereby improving its detection accuracy and reducing detection errors.

[0129] Furthermore, based on the above displacement detection mechanism, the object to be measured is fixedly connected to the magnetic induction reading head. Thus, the displacement detection method of the object to be measured includes the following steps:

[0130] S1: The magnetic induction displacement encoder applies the working principle of rack induction magnetic lines of force, and performs non-contact scanning on the main tooth portion 12 and the vernier tooth portion 13 of the induction teeth 14 whose number difference is 1. The detection unit 21 cuts the induction magnetic lines of force according to the toothed mechanism 1, generates a corresponding number of high-reliability first sine-cosine orthogonal differential signals, and performs real-time correction and compensation for the DC offset error, amplitude error and orthogonal phase error of the first sine-cosine orthogonal differential signal to obtain a second sine-cosine orthogonal cross signal, thereby realizing high-precision detection, compensation and subdivision of the sine-cosine orthogonal differential signal.

[0131] S2: the detection unit 21 generates relative position values ​​of two code tracks (code track formed by the main tooth part 12 and code track formed by the vernier tooth part 13) relative to the power-on moment for the two tracks of the main tooth part 12 and the vernier tooth part 13 (i.e., the second sine-cosine orthogonal differential signal);

[0132] S3: Analyze the phase and phase difference between the two trajectories (i.e., the second sine-cosine orthogonal differential signal) according to the cursor solution principle. Because in this embodiment, NM=1, the phase and phase difference within a stroke are fixed and unique, and then the magnetic induction displacement encoder can calculate the current absolute position and absolute displacement of the measured object through the relative position of the two code channels.

[0133] Thus, in this embodiment, when the magnetic induction chip 211 moves with the object to be measured, when the magnetic induction chip 211 moves to different positions of the toothed mechanism 1 during the movement, the magnetic induction chip 211 generates corresponding sine-cosine orthogonal differential signals according to the different influences of the two relative induction teeth 14 of the main tooth portion 12 and the position change between the vernier tooth portion 13 on the magnetic field generated by the magnetic steel body 31. In addition, the magnetic induction chip 211 can calculate the absolute value of the displacement of the current object to be measured relative to the toothed mechanism 1 by performing tangent operations and a vernier solution algorithm on the original sine-cosine orthogonal differential signals.

[0134] In summary, in the displacement detection mechanism of the present embodiment, the magnetic induction displacement encoder is provided with an independent magnetic mechanism, and a strong magnetic field is generated by the magnetic mechanism. When the magnetic induction reading head moves along the first direction in which the sensing teeth of the main tooth portion and the vernier tooth portion are arranged along the object to be measured, the magnetic field generated by the magnetic mechanism is affected due to the change in the relative position of the sensing teeth of the main tooth portion and the vernier tooth portion. The detection unit can detect the change in the magnetic field generated when the magnetic mechanism is at different positions relative to the toothed mechanism, and generate a corresponding electrical signal, thereby calculating the position of the magnetic induction reading head in the toothed mechanism;

[0135] Furthermore, since an independent magnetic mechanism can be provided to generate a strong magnetic field, when the detection unit detects the change in the magnetic field of the magnetic mechanism relative to the toothed mechanism during movement, the interference of the external magnetic field can be reduced, thereby improving the reliability of the detection by the detection unit, and furthermore, the position of the object to be detected connected to the magnetic induction read head relative to the toothed mechanism can be calculated more accurately;

[0136] Finally, the detection error of the detection unit can be reduced by optimizing the uniformity of the magnetic field generated by the magnetic mechanism.

[0137] In addition, the displacement detection method based on the above-mentioned displacement detection mechanism provided in this embodiment can accurately obtain the position and displacement of the object to be detected relative to the toothed mechanism, thereby improving the detection accuracy.

[0138] This specification discloses the present application with reference to the accompanying drawings, and also enables those skilled in the art to implement the present application, including making and using any device or system, using suitable materials, and using any combined method. The scope of the present application is defined by the technical solution for protection, and includes other examples that occur to those skilled in the art. As long as such other examples include structural elements that are not different from the literal language of the technical solution for protection, or such other examples contain equivalent structural elements that are not substantially different from the literal language of the technical solution for protection, such other examples should be considered to be within the scope of protection determined by the technical solution for protection of the present application.

Claims

1. A magnetic induction displacement encoder, characterized in that: include: A toothed mechanism, the toothed mechanism comprising a base, a main tooth portion, and a vernier tooth portion cooperating with the main tooth portion to affect a magnetic field, the main tooth portion and the vernier tooth portion are both arranged on the same side of the base, the main tooth portion and the vernier tooth portion both comprise a plurality of induction teeth spaced and evenly arranged along a first direction, the interval between two adjacent induction teeth of the main tooth portion is J millimeters, the interval between two adjacent induction teeth of the vernier tooth portion is K millimeters, K>J; A magnetic induction reading head, the magnetic induction reading head comprising a detection unit, the detection unit being arranged on a side of the induction tooth facing away from the base body and forming a detection gap between the detection unit and the induction tooth; A magnetic mechanism, which is disposed on a side of the detection unit facing away from the induction teeth and is fixed to the magnetic induction reading head to generate a magnetic field; The magnetic induction reading head can move along the first direction with the object to be measured, the length of the detection gap has a corresponding relationship with the tooth height of the induction tooth, and the corresponding relationship enables the detection unit to generate an electrical signal for obtaining the displacement of the object to be measured according to the magnetic flux lines of the magnetic field generated by the magnetic mechanism cut by the tooth-shaped mechanism, and the length of the detection gap is the vertical distance between the detection unit and the induction tooth; The magnetic mechanism is a magnetic steel body, and the magnetic steel body has a magnetic field compensation part for generating a uniform magnetic field whose second direction length accounts for more than 50% of the second direction length of the detection plane of the detection unit, and the first direction is perpendicular to the second direction; The magnetic field compensation part is a groove and a protrusion formed by a side of the magnetic steel body facing toward or away from the toothed mechanism, and the protrusion is arranged on the outer periphery of the groove; The groove depth of the groove is h mm, the groove width of the groove is d mm, and the distance between the magnetic steel body and the induction tooth is s mm, then: ； Among them, h>0, d>0, s>0; The tooth height of the sensing tooth is H mm, the length of the detection gap is C mm, and the corresponding relationship is: 0.8≤H / C≤5, wherein 0.3≤C≤1.

2.

2. The magnetic induction displacement encoder according to claim 1, characterized in that: The protrusions are respectively formed on both side edges of the groove along the first direction or the second direction.

3. The magnetic induction displacement encoder according to claim 1, characterized in that: The protrusions are arranged circumferentially along the edge of the groove.

4. The magnetic induction displacement encoder according to any one of claims 1 to 3, characterized in that: A side surface of the protrusion close to the groove is inclined upward and extends outward from the bottom surface of the groove.

5. The magnetic induction displacement encoder according to claim 1, characterized in that: The bottom surface of the groove is smoothly transitionally connected to the plane connected to its periphery.

6. The magnetic induction displacement encoder according to claim 1, characterized in that: The main tooth portion and the cursor tooth portion have the same length in the first direction.

7. The magnetic induction displacement encoder according to claim 1, characterized in that: The number of the inductive teeth of the main tooth portion is N, and the number of the inductive teeth of the vernier tooth portion is M; When NM=1, the magnetic induction displacement encoder is an absolute magnetic induction displacement encoder; When NM≥2, the magnetic induction displacement encoder is a relative magnetic induction displacement encoder.

8. The magnetic induction displacement encoder according to claim 1, characterized in that: The base body, the main tooth portion and the cursor tooth portion are integrally formed.

9. The magnetic induction displacement encoder according to claim 1, characterized in that: The induction teeth are involute teeth.

10. The magnetic induction displacement encoder according to any one of claims 1, 6 to 9, characterized in that: The toothed mechanism is a linear rack.

11. The magnetic induction displacement encoder according to any one of claims 1, 6 to 9, characterized in that: The toothed mechanism is a circular gear or an end-face toothed toothed disc.

12. The magnetic induction displacement encoder according to claim 1, characterized in that: The thickness of the substrate is T millimeters, 0.5≤T≤5.

13. The magnetic induction displacement encoder according to claim 1, characterized in that: The magnetic induction read head further comprises a shell, a receiving cavity is formed in the shell, the detection unit and the magnetic mechanism are both arranged in the receiving cavity, and the magnetic mechanism is arranged on a side of the detection unit facing away from the toothed mechanism.

14. The magnetic induction displacement encoder according to claim 13, characterized in that: The shell is made of non-magnetic material.

15. The magnetic induction displacement encoder according to claim 13, characterized in that: A detection window communicating with the accommodating cavity is formed on a side of the housing facing the toothed mechanism, and the detection unit is arranged opposite to the toothed mechanism through the detection window.

16. The magnetic induction displacement encoder according to claim 13, characterized in that: An opening communicating with the accommodating cavity is formed on a side of the shell body facing away from the toothed mechanism, and the opening is covered with a cover body.

17. The magnetic induction displacement encoder according to claim 16, characterized in that: The cover body is made of magnetic conductive material.

18. The magnetic induction displacement encoder according to claim 1, characterized in that: A magnetic conductive sheet is provided between the magnetic mechanism and the detection unit.

19. The magnetic induction displacement encoder according to claim 18, characterized in that: The two side surfaces of the magnetic conductive sheet are respectively attached to the detection unit and the magnetic mechanism.

20. The magnetic induction displacement encoder according to claim 18, characterized in that: The thickness of the magnetic conductive sheet is A millimeters, 0.1≤A≤1.

21. The magnetic induction displacement encoder according to claim 18, characterized in that: A projection of the magnetic conductive sheet along a direction in which the toothed mechanism approaches the magnetic mechanism coincides with a side surface of the magnetic mechanism facing the toothed mechanism.

22. The magnetic induction displacement encoder according to claim 1, characterized in that: It also includes a magnetic shielding mechanism made of a high magnetic permeability material. Along the first direction, at least one side of the toothed mechanism is provided with the magnetic shielding mechanism, and the magnetic shielding mechanism is extended along the first direction.

23. The magnetic induction displacement encoder according to claim 22, characterized in that: Along the first direction, the magnetic shielding mechanism is provided on both sides of the toothed mechanism.

24. The magnetic induction displacement encoder according to claim 1, characterized in that: The magnetic field strength generated by the magnetic mechanism is B millitesla, 10≤B≤500.

25. A displacement detection mechanism, characterized in that: A magnetic induction displacement encoder comprising any one of claims 1-24.

26. A displacement detection method based on the displacement detection mechanism of claim 25, characterized in that: The following steps are involved: S1: According to the toothed mechanism cutting the induced magnetic lines, a corresponding number of first sine-cosine orthogonal differential signals are generated, and the DC offset error, amplitude error and orthogonal phase error of the first sine-cosine orthogonal differential signal are corrected and compensated in real time to obtain a second sine-cosine orthogonal differential signal; S2: Generate relative position values ​​of the main tooth portion and the vernier tooth portion relative to the power-on moment according to the second sine-cosine orthogonal differential signal; S3: Analyze the phase and phase difference of the second sine-cosine orthogonal differential signal according to the vernier solution principle, and calculate the current displacement position of the measured object.

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