Inductive encoder and motor system

Abstract

The application provides an inductance encoder and a motor system. The inductance encoder comprises a rotor, which can be driven to rotate by a rotating shaft of a motor, and is configured to modulate an electromagnetic field provided by a transmitting coil; a stator, which is provided with the transmitting coil, a first receiving coil and a second receiving coil, the transmitting coil is configured to provide the electromagnetic field, the first receiving coil is configured to sense the modulated electromagnetic field to output a first sensing electric signal, and the second receiving coil is configured to sense the modulated electromagnetic field to output a second sensing electric signal, the stator and the rotor are arranged along an axis of rotation of the rotor; the first receiving coil and the second receiving coil have different pole pair numbers, the first receiving coil and the second receiving coil are arranged along the axis of rotation of the rotor, and the first receiving coil and the second receiving coil are electrically insulated, a first projection of the first receiving coil on a preset plane and a second projection of the second receiving coil on the preset plane at least partially overlap.

Description

Technical Field

[0001] This application relates to the field of inductive encoder technology, and more particularly to an inductive encoder and motor system. Background Technology

[0002] Currently, inductive encoders are widely used in robot joints, servo motors, and industrial automation, among other fields, due to their advantages such as strong resistance to contamination, resistance to high and low temperatures, and high reliability. Inductive encoders include absolute inductive encoders, rotary encoders, linear encoders, and more.

[0003] In related technologies, inductive encoders typically employ a multi-stage receiving coil structure to achieve multi-turn or high-resolution angle detection, which is not conducive to the miniaturization of inductive encoders. Utility Model Content

[0004] In view of this, this application proposes an inductive encoder and motor system, which aims to improve the integration of the inductive encoder in order to promote the miniaturization of the inductive encoder.

[0005] In a first aspect, embodiments of this application provide an inductive encoder, including, The rotor is driven to rotate by the shaft of the motor, and the rotor is used to modulate the electromagnetic field provided by the transmitting coil provided on the stator of the inductive encoder. The stator is provided with a transmitting coil, a first receiving coil and a second receiving coil. The transmitting coil is used to provide an electromagnetic field. The first receiving coil is used to sense the electromagnetic field modulated by the rotor to output a first induced electrical signal. The second receiving coil is used to sense the electromagnetic field modulated by the rotor to output a second induced electrical signal. The stator and the rotor are arranged along the rotation axis of the rotor. The first receiving coil and the second receiving coil have different numbers of pole pairs. The first receiving coil and the second receiving coil are arranged along the rotation axis of the rotor and are electrically insulated from each other. The first projection of the first receiving coil on a preset plane and the second projection of the second receiving coil on the preset plane at least partially overlap. The preset plane includes a plane perpendicular to the rotation axis of the rotor.

[0006] Secondly, embodiments of this application provide a motor system, the motor system including a motor and the aforementioned inductive encoder, the output information of the inductive encoder being able to characterize the rotation angle of the motor.

[0007] In an inductive encoder comprising a rotor and a stator, the stator is provided with a transmitting coil, a first receiving coil, and a second receiving coil, wherein the first receiving coil and the second receiving coil, having different numbers of pole pairs, are arranged along the rotational axis of the rotor, and wherein the first projection of the first receiving coil on a preset plane and the second projection of the second receiving coil on the preset plane at least partially overlap, and the preset plane includes a plane perpendicular to the rotational axis of the rotor, the degree of overlap between the first projection of the first receiving coil and the second projection of the second receiving coil on the preset plane is improved, which is beneficial to improving the integration of the inductive encoder and thus promoting the miniaturization of the inductive encoder.

[0008] Furthermore, when the number of pole pairs of the first receiving coil and the number of pole pairs of the second receiving coil are different, the first induced electrical signal output by the first receiving coil and the second induced electrical signal output by the second receiving coil can be used together to determine the output information of the inductive encoder. The output information can be used to characterize the rotation angle of the motor, which helps to improve the accuracy of the inductive encoder in measuring the rotation angle of the motor. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of the structure of an inductive encoder provided in an embodiment of this application; Figure 2 This is a schematic diagram of the arrangement of the first and second receiving coils according to an embodiment of this application; Figure 3 This is a schematic diagram of the stator structure according to an embodiment of this application; Figure 4 This is a schematic block diagram of the motor system provided in the embodiments of this application.

[0010] Explanation of reference numerals in the attached figures: 10. Motor system; 100. Inductive encoder; 110. Rotor; 111. Conductive pattern; 120. Stator; 121. First receiving coil; 1211. First circle; 1212. First sub-receiving coil; 1213. Second sub-receiving coil; 122. Second receiving coil; 1221. Second circle; 1222. Third sub-receiving coil; 1223. Fourth sub-receiving coil; 130. Preset plane; 131. First projection; 132. Second projection; 133. First orthographic projection; 134. Second orthographic projection; 140. Circuit board; 141. First circuit layer; 1411. First sub-layer; 1412. Second sub-layer; 142. Second circuit layer; 1421. Third sub-layer; 1422. Fourth sub-layer; 143. First dielectric layer; 144. Second dielectric layer; 145. Third dielectric layer; 200. Motor. Detailed Implementation

[0011] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are all within the scope of protection of this application.

[0012] Where there is no conflict, the following embodiments and features can be combined with each other.

[0013] Please see Figure 1 , Figure 1 This is a schematic diagram of the structure of an inductive encoder 100 provided in an embodiment of this application.

[0014] like Figure 1 As shown, the inductive encoder 100 includes a rotor 110 and a stator 120.

[0015] The rotor 110 can be driven to rotate by the shaft (not shown) of the motor 200. The rotor 110 is used to modulate the electromagnetic field provided by the transmitting coil provided on the stator 120 of the inductive encoder 100.

[0016] The stator 120 is provided with a transmitting coil (not shown in the figure), a first receiving coil 121, and a second receiving coil 122. The transmitting coil is used to provide an electromagnetic field. The first receiving coil 121 is used to sense the electromagnetic field modulated by the rotor 110 to output a first induced electrical signal. The second receiving coil 122 is used to sense the electromagnetic field modulated by the rotor 110 to output a second induced electrical signal. The stator 120 and the rotor 110 are arranged along the rotation axis of the rotor 110.

[0017] The first receiving coil 121 and the second receiving coil 122 have different numbers of pole pairs. The first receiving coil 121 and the second receiving coil 122 are arranged along the rotation axis of the rotor 110, and the first receiving coil 121 and the second receiving coil 122 are electrically insulated from each other. The first projection 131 of the first receiving coil 121 on the preset plane 130 and the second projection 132 of the second receiving coil 122 on the preset plane 130 at least partially overlap, and the preset plane 130 includes a plane perpendicular to the rotation axis of the rotor 110.

[0018] When a transmitting coil is provided on the stator 120 of the inductive encoder 100, the transmitting coil can be used to provide an electromagnetic field. The electromagnetic field includes, for example, a high-frequency alternating magnetic field, which is not limited here.

[0019] When the rotor 110 of the inductive encoder 100 can be driven to rotate by the shaft of the motor 200, the rotor 110 can induce eddy currents in the electromagnetic field provided by the stator 120. The eddy currents can generate corresponding magnetic fields, and the magnetic fields corresponding to the eddy currents can change the magnetic field distribution of the electromagnetic field provided by the transmitting coil. Thus, the rotor 110 can be used to modulate the electromagnetic field provided by the transmitting coil provided on the stator 120 of the inductive encoder 100.

[0020] When the inductive encoder 100 has a first receiving coil 121 on its stator 120, the first receiving coil 121 can sense the electromagnetic field modulated by the rotor 110 to output a first induced electrical signal. Correspondingly, when the inductive encoder 100 has a second receiving coil 122 on its stator 120, the second receiving coil 122 can sense the electromagnetic field modulated by the rotor 110 to output a second induced electrical signal.

[0021] The first and second induced electrical signals can be used by the inductive encoder 100 to determine the output information of the inductive encoder 100. The output information of the inductive encoder 100 can be used to characterize the rotation angle of the motor 200. When the number of pole pairs of the first receiving coil 121 and the number of pole pairs of the second receiving coil 122 are different, and the first induced electrical signal output by the first receiving coil 121 and the second induced electrical signal output by the second receiving coil 122 can be used in conjunction to determine the output information of the inductive encoder 100, it is beneficial to improve the accuracy of the inductive encoder 100 in measuring the rotation angle of the motor 200.

[0022] In some embodiments, the inductive encoder 100 can determine the output information of the inductive encoder 100 based on the first induced electrical signal and the second induced electrical signal, that is, determine the output information that can be used to characterize the rotation angle of the motor 200.

[0023] For example, the inductive encoder 100 can be applied to the motor system 10, which also includes the motor 200.

[0024] For example, if the stator 120 of the inductive encoder 100 is connected to the motor 200, and the rotor 110 of the inductive encoder 100 is connected to the shaft of the motor 200, then when the shaft of the motor 200 rotates, the rotor 110 of the inductive encoder 100 can be driven to rotate by the shaft of the motor 200. In this case, the inductive encoder 100 can be directly connected to the shaft of the motor 200 via its rotor 110. Therefore, when the inductive encoder 100 determines its output information based on the first and second induced electrical signals, the output information can be used to characterize the actual rotation angle of the motor 200.

[0025] For example, the motor system 10 may also include a speed reducer. The motor 200 is connected to the speed reducer, and the output of the speed reducer is connected to the inductive encoder 100. When the shaft of the motor 200 rotates, the speed reducer can reduce the rotation of the motor 200 shaft. The motor 200 can be connected to the inductive encoder 100 via the speed reducer, so that when the shaft of the motor 200 rotates, it can still drive the rotor 110 of the inductive encoder 100 to rotate. In this case, the inductive encoder 100 is essentially indirectly connected to the shaft of the motor 200 via the speed reducer. Therefore, when the inductive encoder 100 determines its output information based on the first and second induced electrical signals, the output information of the inductive encoder 100 can be used to characterize the rotation angle of the motor 200 after the speed reduction process.

[0026] Both the actual rotation angle of motor 200 and the rotation angle of motor 200 after speed reduction can represent the rotation angle of motor 200. The following text will uniformly refer to both the actual rotation angle of motor 200 and the rotation angle of motor 200 after speed reduction as the rotation angle of motor 200.

[0027] For example, the inductive encoder 100 can determine a first electrical angle corresponding to a first induced electrical signal and a second electrical angle corresponding to a second induced electrical signal. Then, by combining the first electrical angle and the second electrical angle, the output information of the inductive encoder 100 is determined to characterize the rotation angle of the motor 200. The first electrical angle can be used to indicate the number of sinusoidal cycles completed by the first induced electrical signal induced by the first receiving coil 121. A complete sine wave is one 360° electrical cycle. The second electrical angle can be used to indicate the number of sinusoidal cycles completed by the second induced electrical signal induced by the second receiving coil 122. The first and second electrical angles can be used to determine the mechanical angle of the rotor 110 of the inductive encoder 100. The mechanical angle can be used to characterize the actual rotation angle of the rotor 110. The mechanical angle of the rotor 110 can be used to determine the output information of the inductive encoder 100, and thus the output information of the inductive encoder 100 can be used to characterize the rotation angle of the motor 200.

[0028] For example, the inductive encoder 100 can demodulate the first induced electrical signal to obtain a first voltage value corresponding to the first induced electrical signal. Correspondingly, the inductive encoder 100 can demodulate the second induced electrical signal to obtain a second voltage value corresponding to the second induced electrical signal. The inductive encoder 100 can perform an arctangent operation on the first voltage value to obtain a corresponding first electrical angle. Correspondingly, the inductive encoder 100 can perform an arctangent operation on the second voltage value to obtain a corresponding second electrical angle. Given the first and second electrical angles, the inductive encoder 100 can obtain the final output information based on the first and second electrical angles.

[0029] Taking the example of a first receiving coil 121 comprising a first-cycle sine wave coil and a first-cycle cosine wave coil arranged circumferentially along the rotor 110, and a second receiving coil 122 comprising a second-cycle sine wave coil and a second-cycle cosine wave coil arranged circumferentially along the rotor 110, the circumferential direction of the rotor 110 is used to indicate the circumferential direction of rotation about the rotation axis of the rotor 110. The first-cycle sine wave coil can also be referred to as the first sine winding, and the first-cycle cosine wave coil can also be referred to as the first cosine winding. The second-cycle sine wave coil can also be referred to as the second sine winding, and the second-cycle cosine wave coil can also be referred to as the second cosine winding.

[0030] The number of periods of the first-cycle sine wave coil corresponds to the number of pole pairs of the first receiving coil 121, and the number of periods of the first-cycle cosine wave coil also corresponds to the number of pole pairs of the first receiving coil 121. The number of periods of the second-cycle sine wave coil corresponds to the number of pole pairs of the second receiving coil 122, and the number of periods of the second-cycle cosine wave coil also corresponds to the number of pole pairs of the second receiving coil 122. The number of pole pairs of the first receiving coil 121 and the second receiving coil 122 are different. It is understood that in some embodiments, the number of periods of the above-mentioned coils is equal to the number of pole pairs of the coil.

[0031] The first-cycle sine wave coil can be used to sense the electromagnetic field modulated by the rotor 110 to output a first sine amplitude-modulated signal. The first-cycle cosine wave coil can be used to sense the electromagnetic field modulated by the rotor 110 to output a first cosine amplitude-modulated signal. The first induced electrical signal output by the first receiving coil 121 includes the first sine amplitude-modulated signal and the first cosine amplitude-modulated signal.

[0032] Accordingly, the second-cycle sine wave coil can be used to induce the electromagnetic field modulated by the rotor 110 to output a second sine amplitude-modulated signal. The second-cycle cosine wave coil can be used to induce the electromagnetic field modulated by the rotor 110 to output a second cosine amplitude-modulated signal. The second induced electrical signal output by the second receiving coil 122 includes the second sine amplitude-modulated signal and the second cosine amplitude-modulated signal.

[0033] The inductive encoder 100 can demodulate the first sinusoidal amplitude-modulated signal to obtain the corresponding first sinusoidal voltage value. The inductive encoder 100 can also demodulate the first cosine amplitude-modulated signal to obtain the corresponding first cosine voltage value. The first voltage value corresponding to the first induced electrical signal includes both a first sine voltage value and a first cosine voltage value.

[0034] Accordingly, the inductive encoder 100 can demodulate the second sinusoidal amplitude-modulated signal to obtain the corresponding second sinusoidal voltage value. The inductive encoder 100 can also demodulate the second cosine amplitude-modulated signal to obtain the corresponding second cosine voltage value. The second voltage value corresponding to the second induced electrical signal includes both a second sine voltage value and a second cosine voltage value.

[0035] The inductive encoder 100 can perform arctangent calculation on the first voltage value, which includes the first sine voltage value and the first cosine voltage value, to obtain the corresponding first electrical angle.

[0036] For example, the first electrical angle can be expressed as:

[0037] in, Used to indicate the first electrical angle Used to indicate the first sinusoidal voltage value Used to indicate the value of the first cosine voltage.

[0038] Accordingly, the inductive encoder 100 can perform arctangent calculation on the second voltage value, which includes the second sine voltage value and the second cosine voltage value, to obtain the corresponding second electrical angle.

[0039] For example, the second electrical angle can be expressed as:

[0040] in, Used to indicate the second electrical angle, Used to indicate the second sinusoidal voltage value Used to indicate the value of the second cosine voltage.

[0041] Given a first electrical angle and a second electrical angle, the inductive encoder 100 can obtain the final output information based on the first electrical angle and the second electrical angle.

[0042] For example, the first electrical angle conform to:

[0043] in, Used to indicate the mechanical angle of the rotor 110 of the inductive encoder 100, The output information of the inductive encoder 100 can be used to characterize the rotation angle of the motor 200. Used to indicate the number of pole pairs of the first receiving coil 121. For example, it can be indicated by... Divide by 360° to obtain the remainder, and determine the first electrical angle based on the remainder. .

[0044] Second electrical angle conform to:

[0045] in, Used to indicate the mechanical angle of the rotor 110 of the inductive encoder 100, The output information of the inductive encoder 100 can be used to characterize the rotation angle of the motor 200. Used to indicate the number of pole pairs of the second receiving coil 122. For example, it can be indicated by... Divide by 360° to obtain the remainder, and determine the second electrical angle based on the remainder. .

[0046] With the number of pole pairs of the first receiving coil 121 The number of pole pairs of the second receiving coil 122 is 4. Taking 1 as an example, due to the extreme logarithm Greater than the number of pole pairs Then the first electrical angle It is equivalent to a high-precision and ambiguous precision electrical angle, the second electrical angle. This is equivalent to a low-precision and unambiguous coarse electrical angle. When the number of pole pairs in the second receiving coil 122 is 1, a 1° rotation of the rotor 110 results in a 1° change in the second induced electrical signal. A 360° rotation of the rotor 110 means that for every 360° rotation of the rotor 110, the second induced electrical signal completes one sine wave cycle, with the second induced electrical signal changing 360°. When the number of pole pairs in the first receiving coil 121 is 4, a 1° rotation of the rotor 110 results in a 4° change in the first induced electrical signal. A 360° rotation of the rotor 110 results in a 4×360° change in the first induced electrical signal. This means that for every 90° rotation of the rotor 110, the first induced electrical signal completes one sine wave cycle. Therefore, the inductive encoder 100 can functionally divide the 360° circumference of the rotor 110 into four sectors, corresponding to 0°~90°, 90°~180°, 180°~270°, and 270°~360° respectively.

[0047] For example, at the second electrical angle When the angle is 30°, the number of pole pairs can be used as a reference. The second electrical angle was calculated. The mechanical angle of the rotor 110 of the corresponding inductive encoder 100 It is 30°. Accordingly, at the first electrical angle When the angle is 120°, the number of pole pairs can be considered. The first electrical angle was calculated. The candidate mechanical angles of the rotor 110 of the corresponding inductive encoder 100 include 30°, 120°, 210°, and 300°. Based on this, the inductive encoder 100 can detect the second electrical angle. Corresponding mechanical angle As a criterion for determining the first electrical angle The mechanical angle of the rotor 110 of the corresponding inductive encoder 100 The reference point of the sector in which it is located, and thus from the first electrical angle Among the multiple candidate mechanical angles, the one corresponding to the second electrical angle is selected. Corresponding mechanical angle The candidate mechanical angle with the smallest angular difference between the two is determined as the first electrical angle. Corresponding mechanical angle Correspondingly, in extreme logarithms Greater than the number of pole pairs In this case, the inductive encoder 100 can be based on the first electrical angle Corresponding mechanical angle The output information of the inductive encoder 100 is determined for subsequent processing via the first electrical angle. Corresponding mechanical angle Characterizes the rotation angle of motor 200.

[0048] Of course, the number of pole pairs of the first receiving coil 121 and the number of pole pairs of the second receiving coil 122 are not limited to this, and no restrictions are imposed here.

[0049] Therefore, when the number of pole pairs of the first receiving coil 121 and the number of pole pairs of the second receiving coil 122 are different, the inductive encoder 100 can coordinate with the first induced electrical signal corresponding to the first receiving coil 121 and the second induced electrical signal corresponding to the second receiving coil 122 to determine the output information of the inductive encoder 100. The output information of the inductive encoder 100 can be used to characterize the rotation angle of the motor 200, which helps to improve the accuracy of the inductive encoder 100 in measuring the rotation angle of the motor 200.

[0050] In the inductive encoder 100, the stator 120 and rotor 110 are arranged along the rotational axis of the rotor 110. The rotational axis of the rotor 110 can be used to indicate the direction along the centerline of the rotational axis of the rotor 110. For example, in the inductive encoder 100, the stator 120 and rotor 110 are arranged adjacent to each other along the rotational axis of the rotor 110. Figure 1 As shown, when the rotation axis of rotor 110 is parallel to the vertical direction, stator 120 can be located below rotor 110. Of course, it is not limited to this; when the rotation axis of rotor 110 is parallel to the vertical direction, stator 120 can also be located above rotor 110, without any restriction.

[0051] When the inductive encoder 100 has a first receiving coil 121 and a second receiving coil 122 on its stator 120, the first receiving coil 121 and the second receiving coil 122 are arranged along the rotational axis of the rotor 110. For example, the first receiving coil 121 and the second receiving coil 122 are arranged adjacent to each other along the rotational axis of the rotor 110. Figure 1 As shown, when the rotation axis of the rotor 110 is parallel to the vertical direction, the first receiving coil 121 can be located above the second receiving coil 122. Of course, it is not limited to this; when the rotation axis of the rotor 110 is parallel to the vertical direction, the first receiving coil 121 can also be located below the second receiving coil 122, and there is no restriction here.

[0052] Accordingly, the first receiving coil 121 and the second receiving coil 122 are electrically isolated. For example, a first dielectric layer 143 is provided between the first receiving coil 121 and the second receiving coil 122 along the rotational axis of the rotor 110. The first dielectric layer 143 can be used to achieve electrical insulation between the first receiving coil 121 and the second receiving coil 122. With the first receiving coil 121 and the second receiving coil 122 electrically isolated, the possibility of crosstalk between the first induced electrical signal corresponding to the first receiving coil 121 and the second induced electrical signal corresponding to the second receiving coil 122 can be reduced, thereby improving the accuracy of the inductive encoder 100 in determining the output information of the inductive encoder 100 based on the first induced electrical signal and the second induced electrical signal. This is equivalent to improving the accuracy of the inductive encoder 100 in determining the rotation angle of the motor 200.

[0053] When the first receiving coil 121 and the second receiving coil 122 are arranged along the rotational axis of the rotor 110, the first projection 131 of the first receiving coil 121 on the preset plane 130 and the second projection 132 of the second receiving coil 122 on the preset plane 130 at least partially overlap, and the preset plane 130 includes a plane perpendicular to the rotational axis of the rotor 110. Figure 1As shown, when the rotational axis of the rotor 110 is parallel to the vertical direction, the preset plane 130 is parallel to the horizontal direction, and the normal of the preset plane 130 is parallel to the vertical direction. The inductive encoder 100 can project the first receiving coil 121 along the rotational axis of the rotor 110 onto the preset plane 130 to obtain the first projection 131. Correspondingly, the inductive encoder 100 can project the second receiving coil 122 along the rotational axis of the rotor 110 onto the preset plane 130 to obtain the second projection 132. Since the first receiving coil 121 and the second receiving coil 122 are arranged along the rotational axis of the rotor 110, it can be ensured that the first projection 131 and the second projection 132 at least partially overlap on the preset plane 130. Based on this, when designing the first receiving coil 121 and the second receiving coil 122, the inductive encoder 100 does not need to arrange the first receiving coil 121 and the second receiving coil 122 in a planar unfolded manner, but can arrange the first receiving coil 121 and the second receiving coil 122 along the rotational axis of the rotor 110. Figure 1 As shown, when the first receiving coil 121 and the second receiving coil 122 are arranged along the downward rotation axis of the rotor 110, it can be ensured that the first projection 131 and the second projection 132 at least partially overlap. This is equivalent to increasing the degree of overlap between the first projection 131 corresponding to the first receiving coil 121 and the second projection 132 corresponding to the second receiving coil 122 on the preset plane 130, which is beneficial to improving the integration of the inductive encoder 100 and thus promoting the miniaturization of the inductive encoder 100.

[0054] In some embodiments, the rotor 110 is provided with a conductive pattern 111. When the rotor 110 rotates, the conductive pattern 111 can change the mutual inductance parameter between the transmitting coil and the first receiving coil 121, and change the mutual inductance parameter between the transmitting coil and the second receiving coil 122, so as to modulate the electromagnetic field provided by the transmitting coil.

[0055] The conductive pattern 111 can induce eddy currents in the electromagnetic field provided by the transmitting coil. The eddy currents induced by the conductive pattern 111 generate a secondary magnetic field opposite in direction to the electromagnetic field provided by the transmitting coil. This allows the conductive pattern 111 to shield the electromagnetic field provided by the transmitting coil, i.e., to generate an eddy current shielding effect. As the rotor 110 rotates, the conductive pattern 111 can, based on the eddy current shielding effect, change the mutual inductance parameters between the transmitting coil and the first receiving coil 121, and also change the mutual inductance parameters between the transmitting coil and the second receiving coil 122, thereby modulating the electromagnetic field provided by the transmitting coil.

[0056] For example, the conductive pattern 111 can be arranged circumferentially along the rotor 110, such as around the rotation axis of the rotor 110. The conductive pattern 111 includes a conductive grid. The conductive grid can also be referred to as copper foil, copper foil grid, or at least one of these, without limitation herein. The conductive grid is periodic. Figure 1 As shown, the conductive pattern 111 may have multiple conductive grids, which are arranged along the circumference of the rotor 110, and there is a blank area between every two adjacent conductive grids arranged along the circumference of the rotor 110.

[0057] For example, as the rotor 110 rotates, the conductive grid included in the conductive pattern 111 can gradually approach the first magnetic field sensing window formed in space by the first receiving coil 121, so that the coverage area of ​​the conductive grid over the first magnetic field sensing window gradually increases until the coverage area of ​​the conductive grid over the first magnetic field sensing window reaches its maximum value. As the rotor 110 continues to rotate, the conductive grid can gradually move away from the first magnetic field sensing window, so that the coverage area of ​​the conductive grid over the first magnetic field sensing window gradually decreases, and the coverage area of ​​the blank area over the first magnetic field sensing window gradually increases until the coverage area of ​​the conductive grid over the first magnetic field sensing window reaches its minimum value. By repeating this cycle, the conductive pattern 111 provided on the rotor 110 can be used to change the mutual inductance parameters between the transmitting coil and the first receiving coil 121.

[0058] As the coverage area of ​​the conductive grid over the first magnetic field sensing window gradually increases, the eddy current shielding effect of the conductive grid on the first magnetic field sensing window gradually strengthens. Therefore, the conductive grid can gradually reduce the mutual inductance parameter between the transmitting coil and the first receiving coil 121 until the mutual inductance parameter between the transmitting coil and the first receiving coil 121 reaches its minimum value. Conversely, as the coverage area of ​​the conductive grid over the first magnetic field sensing window gradually decreases, the eddy current shielding effect of the conductive grid on the first magnetic field sensing window gradually weakens. Therefore, the conductive grid can gradually increase the mutual inductance parameter between the transmitting coil and the first receiving coil 121 until the mutual inductance parameter between the transmitting coil and the first receiving coil 121 reaches its maximum value.

[0059] Based on this, during the rotation of rotor 110, rotor 110 can modulate the electromagnetic field provided by the transmitting coil through conductive pattern 111, so that the first receiving coil 121 can sense the electromagnetic field modulated by rotor 110 and then output the first induced electrical signal.

[0060] Accordingly, as the rotor 110 rotates, the conductive grid included in the conductive pattern 111 can gradually approach the second magnetic field sensing window formed in space by the second receiving coil 122, so that the coverage area of ​​the conductive grid on the second magnetic field sensing window gradually increases until the coverage area of ​​the conductive grid on the second magnetic field sensing window reaches its maximum value. As the rotor 110 continues to rotate, the conductive grid can gradually move away from the second magnetic field sensing window, so that the coverage area of ​​the conductive grid on the second magnetic field sensing window gradually decreases, and the coverage area of ​​the blank area on the second magnetic field sensing window gradually increases until the coverage area of ​​the conductive grid on the second magnetic field sensing window reaches its minimum value. In this cycle, the conductive pattern 111 provided on the rotor 110 can be used to change the mutual inductance parameters between the transmitting coil and the second receiving coil 122.

[0061] As the coverage area of ​​the conductive grid over the second magnetic field sensing window gradually increases, the eddy current shielding effect of the conductive grid on the second magnetic field sensing window gradually strengthens. Therefore, the conductive grid can gradually reduce the mutual inductance parameter between the transmitting coil and the second receiving coil 122 until the mutual inductance parameter between the transmitting coil and the second receiving coil 122 reaches its minimum value. Conversely, as the coverage area of ​​the conductive grid over the second magnetic field sensing window gradually decreases, the eddy current shielding effect of the conductive grid on the second magnetic field sensing window gradually weakens. Therefore, the conductive grid can gradually increase the mutual inductance parameter between the transmitting coil and the second receiving coil 122 until the mutual inductance parameter between the transmitting coil and the second receiving coil 122 reaches its maximum value.

[0062] Based on this, during the rotation of rotor 110, rotor 110 can modulate the electromagnetic field provided by the transmitting coil through conductive pattern 111, so that the second receiving coil 122 can sense the electromagnetic field modulated by rotor 110 and then output the second induced electrical signal.

[0063] Based on the conductive pattern 111 on the rotor 110 of the inductive encoder 100, the inductive encoder 100 can output a first induced electrical signal through the first receiving coil 121 and a second induced electrical signal through the second receiving coil 122 when the rotor 110 rotates. The first and second induced electrical signals can be used by the inductive encoder 100 to determine its output information. Since the output information of the inductive encoder 100 can characterize the rotation angle of the motor 200, it is beneficial to improve the ease of determining the rotation angle of the motor 200 using the inductive encoder 100. Furthermore, when the number of pole pairs of the first receiving coil 121 and the second receiving coil 122 are different, the first induced electrical signal output by the first receiving coil 121 and the second induced electrical signal output by the second receiving coil 122 can be used collaboratively to determine the output information of the inductive encoder 100. Since the output information can characterize the rotation angle of the motor 200, it is beneficial to improve the measurement accuracy of the rotation angle of the motor 200 by the inductive encoder 100.

[0064] In some embodiments, the conductive pattern 111 includes a first conductive pattern and a second conductive pattern. The first conductive pattern includes a first conductive grid, the number of periods of which corresponds to the number of pole pairs of the first receiving coil 121. The second conductive pattern includes a second conductive grid, the number of periods of which corresponds to the number of pole pairs of the second receiving coil 122.

[0065] For example, the conductive pattern 111 may include a first conductive pattern and a second conductive pattern. The first conductive pattern includes a first conductive grid, the number of periods of which corresponds to the number of pole pairs of the first receiving coil 121, such that the first conductive grid is correspondingly arranged with respect to the first receiving coil 121. Correspondingly, the second conductive pattern includes a second conductive grid, the number of periods of which corresponds to the number of pole pairs of the second receiving coil 122, such that the second conductive grid is correspondingly arranged with respect to the second receiving coil 122.

[0066] For example, the first conductive pattern and the second conductive pattern are arranged along the rotational axis of the rotor 110. For instance, the first conductive pattern and the second conductive pattern are arranged adjacent to each other along the rotational axis of the rotor 110. In some exemplary embodiments, the rotor 110 may include at least two preset circuit boards, and the at least two preset circuit boards are arranged along the rotational axis of the rotor 110. The first conductive pattern and the second conductive pattern may be disposed on different preset circuit boards. In other exemplary embodiments, the rotor 110 may include at least one preset circuit board, and the preset circuit board includes at least two preset circuit layers. Taking an example where the at least two preset circuit layers include a first preset circuit layer and a second preset circuit layer. The first preset circuit layer and the second preset circuit layer are arranged adjacent to each other along the rotational axis of the rotor 110. The first conductive pattern may be formed on the first preset circuit layer, and the second conductive pattern may be formed on the second preset circuit layer.

[0067] When the conductive pattern 111 includes a first conductive pattern, the first conductive pattern includes a first conductive grid, and the number of periods of the first conductive grid corresponds to the number of pole pairs of the first receiving coil 121, the first conductive pattern can be used to change the mutual inductance parameter between the transmitting coil and the first receiving coil 121 when the rotor 110 rotates, thereby modulating the electromagnetic field provided by the transmitting coil. The first receiving coil 121 can then sense the electromagnetic field modulated by the first conductive pattern included in the rotor 110 to output a first induced electrical signal.

[0068] Accordingly, when the conductive pattern 111 includes a second conductive pattern, the second conductive pattern includes a second conductive grid, and the number of periods of the second conductive grid corresponds to the number of pole pairs of the second receiving coil 122, the second conductive pattern can be used to change the mutual inductance parameter between the transmitting coil and the second receiving coil 122 when the rotor 110 rotates, thereby modulating the electromagnetic field provided by the transmitting coil. The second receiving coil 122 can then sense the electromagnetic field modulated by the second conductive pattern included in the rotor 110 to output a second induced electrical signal.

[0069] Since the number of pole pairs of the first receiving coil 121 and the number of pole pairs of the second receiving coil 122 are different, the number of periods of the first conductive grid and the number of periods of the second conductive grid are also different, which makes the number of pole pairs of the first receiving coil 121 different from the number of periods of the second conductive grid, and the number of pole pairs of the second receiving coil 122 different from the number of periods of the first conductive grid.

[0070] When the number of pole pairs of the first receiving coil 121 corresponds to the number of periods of the first conductive grid, and the number of pole pairs of the first receiving coil 121 is different from the number of periods of the second conductive grid, the first receiving coil 121 can be used as a spatial filter for electromagnetic orthogonal decoupling. That is, the first receiving coil 121 can respond to the electromagnetic field modulated by the first conductive grid and decouple the electromagnetic field modulated by the second conductive grid to output the first induced electrical signal.

[0071] Accordingly, when the number of pole pairs of the second receiving coil 122 corresponds to the number of periods of the second conductive grid, and the number of pole pairs of the second receiving coil 122 is different from the number of periods of the first conductive grid, the second receiving coil 122 can be used as a spatial filter for electromagnetic orthogonal decoupling. That is, the second receiving coil 122 can respond to the electromagnetic field modulated by the second conductive grid and decouple the electromagnetic field modulated by the first conductive grid to output the second induced electrical signal.

[0072] Taking an example where the first receiving coil 121 has 8 pole pairs and the second receiving coil 122 has 5 pole pairs, the first conductive pattern can include 8 first conductive grids. There is a blank area between every two adjacent first conductive grids arranged circumferentially along the rotor 110. The inductive encoder 100 can then determine the period of a first conductive grid based on one adjacent first conductive grid and one blank area arranged circumferentially along the rotor 110, thus making the number of periods of the first conductive grid equal to 8. Correspondingly, the second conductive pattern can include 5 second conductive grids. There is a blank area between every two adjacent second conductive grids arranged circumferentially along the rotor 110. The inductive encoder 100 can then determine the period of a second conductive grid based on one adjacent second conductive grid and one blank area arranged circumferentially along the rotor 110. And so on. Of course, the number of pole pairs of the first receiving coil 121, the number of periods of the first conductive grid, the number of pole pairs of the second receiving coil 122, and the number of periods of the second conductive grid are not limited to these values ​​and are not restricted here.

[0073] Based on the configuration of the first conductive grid, the first conductive grid can be used to change the mutual inductance parameter between the transmitting coil and the first receiving coil 121 to modulate the electromagnetic field provided by the transmitting coil, thereby causing the first receiving coil 121 to sense the electromagnetic field modulated by the first conductive grid, and thus outputting a first induced electrical signal. Based on the configuration of the second conductive grid, the second conductive grid can be used to change the mutual inductance parameter between the transmitting coil and the second receiving coil 122 to modulate the electromagnetic field provided by the transmitting coil, thereby causing the second receiving coil 122 to sense the electromagnetic field modulated by the second conductive grid, and thus outputting a second induced electrical signal. By setting the number of periods of the first conductive grid and the second conductive grid, the interference of the second conductive grid on the first induced electrical signal and the interference of the first conductive grid on the second induced electrical signal can be reduced, which is beneficial to improving the determination accuracy of the first and second induced electrical signals. The first and second induced electrical signals can be used by the inductive encoder 100 to determine the output information of the inductive encoder 100. The output information of the inductive encoder 100 can be used to characterize the rotation angle of the motor 200, which is beneficial to improving the accuracy of the inductive encoder 100 in measuring the rotation angle of the motor 200.

[0074] In some embodiments, the first receiving coil 121 includes a first periodic sinusoidal waveform coil arranged circumferentially along the rotor 110, the number of periods of the first periodic sinusoidal waveform coil corresponding to the number of pole pairs of the first receiving coil 121. The second receiving coil 122 includes a second periodic sinusoidal waveform coil arranged circumferentially along the rotor 110, the number of periods of the second periodic sinusoidal waveform coil corresponding to the number of pole pairs of the second receiving coil 122. The circle formed by the midpoints of the multiple peaks and troughs of the first periodic sinusoidal waveform coil is a first circle 1211, and the circle formed by the midpoints of the multiple peaks and troughs of the second periodic sinusoidal waveform coil is a second circle 1221. The first orthographic projection 133 of the first circle 1211 onto the preset plane 130 coincides with the second orthographic projection 134 of the second circle 1221 onto the preset plane 130.

[0075] For example, the first receiving coil 121 includes a first-period sinusoidal waveform coil arranged circumferentially along the rotor 110. The first-period sinusoidal waveform coil has a periodic sinusoidal waveform shape. Figure 2As shown, the first-cycle sinusoidal waveform coil has multiple peaks and troughs, and there is a trough between every two adjacent peaks arranged circumferentially along the rotor 110. The inductive encoder 100 can start from one of the peaks of the first-cycle sinusoidal waveform coil, follow the direction of the first-cycle sinusoidal waveform coil through a trough, and continue along the direction of the first-cycle sinusoidal waveform coil to the next peak. The next peak can then be used as the endpoint. By combining the portions of the first-cycle sinusoidal waveform coil corresponding to the endpoint, one cycle of the first-cycle sinusoidal waveform coil can be determined. This process can be repeated to determine the number of cycles of the first-cycle sinusoidal waveform. Furthermore, the inductive encoder 100 can be designed so that the number of cycles of the first-cycle sinusoidal waveform coil corresponds to the number of pole pairs of the first receiving coil 121. The first-cycle sinusoidal waveform coil can be used by the first receiving coil 121 to sense the electromagnetic field modulated by the rotor 110, thereby outputting a first induced electrical signal.

[0076] Accordingly, the second receiving coil 122 includes a second-period sinusoidal waveform coil arranged circumferentially along the rotor 110. The second-period sinusoidal waveform coil has a periodic sinusoidal waveform shape. Figure 2 As shown, the second-cycle sinusoidal waveform coil has multiple peaks and troughs, and there is a trough between every two adjacent peaks arranged circumferentially along the rotor 110. The inductive encoder 100 can start from one of the peaks of the second-cycle sinusoidal waveform coil, follow the direction of the second-cycle sinusoidal waveform coil through a trough, and continue along the direction of the second-cycle sinusoidal waveform coil to the next peak. The next peak can then be used as the endpoint, and the corresponding portion of the second-cycle sinusoidal waveform coil from the start to the endpoint can be combined to determine one cycle of the second-cycle sinusoidal waveform coil. This process can be repeated to determine the number of cycles of the second-cycle sinusoidal waveform. Furthermore, the inductive encoder 100 can be designed so that the number of cycles of the second-cycle sinusoidal waveform coil corresponds to the number of pole pairs of the second receiving coil 122. The second-cycle sinusoidal waveform coil can be used by the second receiving coil 122 to sense the electromagnetic field modulated by the rotor 110 to output a second induced electrical signal.

[0077] like Figure 2 As shown, there is a midpoint between each peak and trough of the first-cycle sinusoidal waveform coil. Therefore, when the first-cycle sinusoidal waveform coil has multiple peaks and troughs, it can have multiple midpoints between peaks and troughs. When the first-cycle sinusoidal waveform coil is arranged circumferentially along the rotor 110, connecting the midpoints of multiple peaks and troughs of the first-cycle sinusoidal waveform coil sequentially forms a circle, resulting in the first circle 1211 formed by the midpoints of multiple peaks and troughs of the first-cycle sinusoidal waveform coil.

[0078] Accordingly, such as Figure 2As shown, there is a midpoint between each peak and trough of the second-cycle sinusoidal waveform coil. Therefore, when the second-cycle sinusoidal waveform coil has multiple peaks and troughs, it can have multiple midpoints between peaks and troughs. When the second-cycle sinusoidal waveform coil is arranged circumferentially along the rotor 110, connecting the midpoints of multiple peaks and troughs of the second-cycle sinusoidal waveform coil sequentially can form a circle, thus obtaining the second circle 1221 formed by the midpoints of multiple peaks and troughs of the second-cycle sinusoidal waveform coil.

[0079] like Figure 2 As shown, when the first circle 1211 and the second circle 1221 are projected onto the preset plane 130 along the rotation axis of the rotor 110, a first orthographic projection 133 of the first circle 1211 on the preset plane 130 and a second orthographic projection 134 of the second circle 1221 on the preset plane 130 can be obtained. Since the first receiving coil 121 and the second receiving coil 122 are arranged along the rotation axis of the rotor 110, and the first projection 131 of the first receiving coil 121 on the preset plane 130 and the second projection 132 of the second receiving coil 122 on the preset plane 130 at least partially overlap, it can be ensured that the first orthographic projection 133 of the first circle 1211 onto the preset plane 130 and the second orthographic projection 134 of the second circle 1221 onto the preset plane 130 coincide.

[0080] When the first orthographic projection 133 of the first circle 1211 onto the preset plane 130 coincides with the second orthographic projection 134 of the second circle 1221 onto the preset plane 130, the degree of overlap between the first projection 131 corresponding to the first receiving coil 121 and the second projection 132 corresponding to the second receiving coil 122 can be increased, which is conducive to improving the integration of the inductive encoder 100 and thus promoting the miniaturization of the inductive encoder 100.

[0081] Of course, the first receiving coil 121 and the second receiving coil 122 are not limited to this. For example, the first receiving coil 121 also includes a first-period cosine waveform coil arranged circumferentially along the rotor 110. The number of periods of the first-period cosine waveform coil corresponds to the number of pole pairs of the first receiving coil 121. The second receiving coil 122 also includes a second-period cosine waveform coil arranged circumferentially along the rotor 110. The number of periods of the second-period cosine waveform coil corresponds to the number of pole pairs of the second receiving coil 122. The circle formed by the midpoints of the multiple peaks and troughs of the first-period cosine waveform coil is a third circle, and the circle formed by the midpoints of the multiple peaks and troughs of the second-period cosine waveform coil is a fourth circle. The third orthographic projection of the third circle onto the preset plane 130 coincides with the fourth orthographic projection of the fourth circle onto the preset plane 130. The relevant descriptions of the first-period cosine waveform coil and the second-period cosine waveform coil can be referred to the aforementioned descriptions of the first-period sine waveform coil and the second-period sine waveform coil, and will not be repeated here.

[0082] In some embodiments, the first receiving coil 121 is positioned closer to the transmitting coil in the rotational axis of the rotor 110 than the second receiving coil 122, and the number of pole pairs of the first receiving coil 121 is greater than the number of pole pairs of the second receiving coil 122.

[0083] For example, the transmitting coil can be integrated with the first receiving coil 121.

[0084] For example, when the first receiving coil 121 and the second receiving coil 122 are respectively disposed on different circuit boards 140 included in the stator 120, the transmitting coil can be disposed on the same circuit board 140 of the stator 120 as the first receiving coil 121, thereby making the first receiving coil 121 closer to the transmitting coil in the rotational axis of the rotor 110 than the second receiving coil 122.

[0085] For example, when the first receiving coil 121 and the second receiving coil 122 are respectively disposed on different circuit layers of the same circuit board 140 included in the stator 120, the transmitting coil can be disposed on the same circuit layer of the same circuit board 140 as the first receiving coil 121, thereby making the first receiving coil 121 closer to the transmitting coil on the rotation axis of the rotor 110 than the second receiving coil 122.

[0086] For example, the transmitting coil can be set up independently.

[0087] For example, when the stator 120 includes at least two circuit boards 140, the transmitting coil, the first receiving coil 121 and the second receiving coil 122 can be respectively disposed on different circuit boards 140 included in the stator 120, and the circuit board 140 where the first receiving coil 121 is located is located between the circuit board 140 where the stator 120 is located and the circuit board 140 where the second receiving coil 122 is located in the rotational axis of the rotor 110, so that the first receiving coil 121 is disposed closer to the transmitting coil in the rotational axis of the rotor 110 than the second receiving coil 122.

[0088] For example, when the circuit board 140 of the stator 120 includes at least two circuit layers, the transmitting coil, the first receiving coil 121 and the second receiving coil 122 can be respectively disposed on different circuit layers of the same circuit board 140, and the circuit layer where the first receiving coil 121 is located is located between the circuit layer where the stator 120 is located and the circuit layer where the second receiving coil 122 is located in the rotational axis of the rotor 110, so that the first receiving coil 121 is disposed closer to the transmitting coil in the rotational axis of the rotor 110 than the second receiving coil 122.

[0089] When the first receiving coil 121 is positioned closer to the transmitting coil in the rotational axis of the rotor 110 than the second receiving coil 122, the number of pole pairs of the first receiving coil 121 can be simultaneously set to be greater than the number of pole pairs of the second receiving coil 122.

[0090] Taking the example that the area of ​​the stator 120 occupied by the first receiving coil 121 is the same as the area of ​​the stator 120 occupied by the second receiving coil 122, when the number of pole pairs of the first receiving coil 121 is greater than the number of pole pairs of the second receiving coil 122, the area of ​​the stator 120 occupied by the first receiving coil 121 in each cycle is smaller than the area of ​​the stator 120 occupied by the second receiving coil 122 in each cycle. Consequently, the intensity of the first induced electrical signal that can be sensed by the first receiving coil 121 in each cycle is lower than the intensity of the second induced electrical signal that can be sensed by the second receiving coil 122 in each cycle. Correspondingly, a conductive pattern 111 is provided on the rotor 110. The conductive pattern 111 includes a first conductive pattern and a second conductive pattern. The first conductive pattern includes a first conductive grid, and the second conductive pattern includes a second conductive grid. The number of periods of the first conductive grid corresponds to the number of pole pairs of the first receiving coil 121, and the number of periods of the second conductive grid corresponds to the number of pole pairs of the second receiving coil 122. In this case, the area of ​​the rotor 110 occupied by the first conductive grid is smaller than the area occupied by the second conductive grid. Therefore, the intensity of the electromagnetic field modulated by the first conductive grid is lower than the intensity of the electromagnetic field modulated by the second conductive grid. Since the intensity of the first induced electrical signal induced by the first receiving coil 121 in each cycle is lower than the intensity of the second induced electrical signal induced by the second receiving coil 122 in each cycle, and / or the intensity of the electromagnetic field modulated by the first conductive grid is lower than the intensity of the electromagnetic field modulated by the second conductive grid, it is easy for the signal intensity of the first induced electrical signal output by the first receiving coil 121 to be lower than the signal intensity of the second induced electrical signal output by the second receiving coil 122.

[0091] However, when the number of pole pairs of the first receiving coil 121 is greater than the number of pole pairs of the second receiving coil 122, the accuracy of determining the output information of the inductive encoder 100 by the first induced electrical signal is higher than the accuracy of determining the output information of the inductive encoder 100 by the second induced electrical signal. Therefore, based on the consideration of improving the accuracy of determining the output information of the inductive encoder 100, the positions of the first receiving coil 121 and the second receiving coil 122 can be designed. For example, the first receiving coil 121 can be positioned closer to the transmitting coil in the rotational axis of the rotor 110 than the second receiving coil 122, so as to enhance the signal strength of the first induced electrical signal, which is beneficial to improving the accuracy of determining the output information of the inductive encoder 100.

[0092] Furthermore, with the first receiving coil 121 positioned closer to the transmitting coil along the rotational axis of the rotor 110 than the second receiving coil 122, and the number of pole pairs in the first receiving coil 121 being greater than that in the second receiving coil 122, the first receiving coil 121 can be positioned closer to the electromagnetic field provided by the transmitting coil. This can improve the anti-interference capability of the first receiving coil 121, thereby reducing the adverse effects of stray electromagnetic interference on the first induced electrical signal output by the first receiving coil 121. This can further improve the accuracy of determining the output information of the inductive encoder 100.

[0093] In some embodiments, the stator 120 includes at least two circuit boards 140, with the first receiving coil 121 and the second receiving coil 122 respectively disposed on different circuit boards 140.

[0094] For example, circuit board 140 can be a flexible printed circuit board or a rigid-flex board, without limitation.

[0095] For example, the stator 120 includes at least two circuit boards 140, which are arranged along the rotational axis of the rotor 110. Thus, the first receiving coil 121 and the second receiving coil 122 can be respectively disposed on different circuit boards 140, such that the first receiving coil 121 and the second receiving coil 122 are arranged along the axial direction of the rotor 110. Alternatively, the at least two circuit boards 140 included in the stator 120 can be arranged adjacent to each other along the rotational axis of the rotor 110, and thus the first receiving coil 121 and the second receiving coil 122 can be respectively disposed on different circuit boards 140, such that the first receiving coil 121 and the second receiving coil 122 are arranged along the axial direction of the rotor 110. Accordingly, an air gap can exist between the different circuit boards 140 to achieve electrical insulation between them. Of course, the method of achieving electrical insulation between the different circuit boards 140 is not limited to this, and is not restricted here.

[0096] In some embodiments, the stator 120 includes at least one circuit board 140, on which the first receiving coil 121 and the second receiving coil 122 are formed.

[0097] For example, the stator 120 includes at least one circuit board 140. The same circuit board 140 may include at least two circuit layers, and these at least two circuit layers are arranged along the rotational axis of the rotor 110. Consequently, the first receiving coil 121 and the second receiving coil 122 may be formed on different circuit layers of the same circuit board 140, such that the first receiving coil 121 and the second receiving coil 122 are arranged along the axial direction of the rotor 110. For instance, the at least two circuit layers included in the same circuit board 140 of the stator 120 may be arranged adjacent to each other along the rotational axis of the rotor 110. Consequently, the first receiving coil 121 and the second receiving coil 122 may be formed on different circuit layers of the same circuit board 140, such that the first receiving coil 121 and the second receiving coil 122 are arranged along the axial direction of the rotor 110.

[0098] When the first receiving coil 121 and the second receiving coil 122 can be disposed on different circuit boards 140, or when the first receiving coil 121 and the second receiving coil 122 can be formed on the same circuit board 140, the arrangement of the first receiving coil 121 and the second receiving coil 122 is diverse, which is beneficial to improving the flexibility of the arrangement of the first receiving coil 121 and the second receiving coil 122.

[0099] In some embodiments, the circuit board 140 includes a first circuit layer 141, a first dielectric layer 143, and a second circuit layer 142 arranged sequentially along the rotation axis of the rotor 110. A first receiving coil 121 is formed on the first circuit layer 141, and a second receiving coil 122 is formed on the second circuit layer 142. The first dielectric layer 143 is used to achieve electrical insulation between the first receiving coil 121 and the second receiving coil 122.

[0100] The circuit board 140 includes a first circuit layer 141, a first dielectric layer 143, and a second circuit layer 142 arranged sequentially along the rotational axis of the rotor 110. A first receiving coil 121 is formed on the first circuit layer 141, and a second receiving coil 122 is formed on the second circuit layer 142, so that the first receiving coil 121 and the second receiving coil 122 can be formed on the same circuit board 140. Figure 3 As shown, the first circuit layer 141, the first dielectric layer 143, and the second circuit layer 142 can be arranged adjacent to each other along the rotation axis of the rotor 110, and a first receiving coil 121 is formed on the first circuit layer 141, and a second receiving coil 122 is formed on the second circuit layer 142.

[0101] Accordingly, since a first dielectric layer 143 is provided between the first circuit layer 141 and the second circuit layer 142, and the first dielectric layer 143 can be an insulating medium, the first dielectric layer 143 can be used to achieve electrical insulation between the first receiving coil 121 and the second receiving coil 122.

[0102] Based on this, the arrangement of the first dielectric layer 143 in the circuit board 140 can reduce the possibility of mutual interference between the first receiving coil 121 and the second receiving coil 122, thereby improving the output accuracy of the first receiving coil 121 for the first induced electrical signal and the output accuracy of the second receiving coil 122 for the second induced electrical signal, which is beneficial to improving the determination accuracy of the output information of the inductive encoder 100 in the future.

[0103] In some embodiments, the first circuit layer 141 includes a first sublayer 1411 and a second sublayer 1412, and the first receiving coil 121 includes a first sub-receiving coil 1212 and a second sub-receiving coil 1213. The first sub-receiving coil 1212 is formed on the first sublayer 1411, and the second sub-receiving coil 1213 is formed on the second sublayer 1412.

[0104] For example, the same circuit layer may include multiple sub-layers.

[0105] like Figure 3 As shown, the first circuit layer 141 includes a first sub-layer 1411 and a second sub-layer 1412. The first receiving coil 121 may include a first sub-receiving coil 1212 and a second sub-receiving coil 1213. The first sub-receiving coil 1212 may include, for example, one of a first-cycle sine wave coil and a first-cycle cosine wave coil, and the second sub-receiving coil 1213 may include the other of a first-cycle sine wave coil and a first-cycle cosine wave coil. Of course, it is not limited to this, and no limitation is made here.

[0106] like Figure 3 As shown, a first sub-receiving coil 1212 is formed on a first sub-layer 1411, and a second sub-receiving coil 1213 is formed on a second sub-layer 1412, such that the first sub-receiving coil 1212 and the second sub-receiving coil 1213 can be arranged along the rotational axis of the rotor 110. For example, the first sub-receiving coil 1212 and the second sub-receiving coil 1213 can be arranged adjacent to each other along the rotational axis of the rotor 110.

[0107] The second circuit layer 142 includes a third sublayer 1421 and a fourth sublayer 1422, and the second receiving coil 122 includes a third sub-receiving coil 1222 and a fourth sub-receiving coil 1223. The third sub-receiving coil 1222 is formed on the third sublayer 1421, and the fourth sub-receiving coil 1223 is formed on the fourth sublayer 1422.

[0108] like Figure 3As shown, the second circuit layer 142 includes a third sub-layer 1421 and a fourth sub-layer 1422. The second receiving coil 122 may include a third sub-receiving coil 1222 and a fourth sub-receiving coil 1223. The third sub-receiving coil 1222 may include, for example, one of a second-cycle sine wave coil and a second-cycle cosine wave coil, and the fourth sub-receiving coil 1223 may include the other of a second-cycle sine wave coil and a second-cycle cosine wave coil. Of course, it is not limited to these, and no limitation is made here.

[0109] like Figure 3 As shown, a third sub-receiving coil 1222 is formed on a third sub-layer 1421, and a fourth sub-receiving coil 1223 is formed on a fourth sub-layer 1422, such that the third sub-receiving coil 1222 and the fourth sub-receiving coil 1223 can be arranged along the rotational axis of the rotor 110. For example, the third sub-receiving coil 1222 and the fourth sub-receiving coil 1223 can be arranged adjacent to each other along the rotational axis of the rotor 110.

[0110] When the first receiving coil 121 includes a first sub-receiving coil 1212 and a second sub-receiving coil 1213 arranged along the rotational axis of the rotor 110, and the second receiving coil 122 includes a third sub-receiving coil 1222 and a fourth sub-receiving coil 1223 arranged along the axial direction of the rotor 110, the arrangement of the first receiving coil 121 and the second receiving coil 122 along the axial direction of the rotor 110 is beneficial to improving the integration of the inductive encoder 100, and thus facilitates the miniaturization of the inductive encoder 100.

[0111] The circuit board 140 also includes a second dielectric layer 144 located between the first sub-layer 1411 and the second sub-layer 1412, and a third dielectric layer 145 located between the third sub-layer 1421 and the fourth sub-layer 1422. The second dielectric layer 144 is used to achieve electrical insulation between the first sub-receiving coil 1212 and the second sub-receiving coil 1213, and the third dielectric layer 145 is used to achieve electrical insulation between the third sub-receiving coil 1222 and the fourth sub-receiving coil 1223.

[0112] To reduce the possibility of mutual interference between the first sub-receiving coil 1212 and the second sub-receiving coil 1213, and thereby improve the accuracy of the first receiving coil 121's output of the first induced electrical signal, the circuit board 140 also includes a second dielectric layer 144 located between the first sub-layer 1411 and the second sub-layer 1412. For example... Figure 3As shown, the first sub-layer 1411, the second dielectric layer 144, and the second sub-layer 1412 are arranged sequentially along the rotational axis of the rotor 110. For example, the first sub-layer 1411, the second dielectric layer 144, and the second sub-layer 1412 are arranged adjacent to each other along the rotational axis of the rotor 110. The second dielectric layer 144 may be made of an insulating material so that it can be used to provide electrical insulation between the first sub-receiving coil 1212 and the second sub-receiving coil 1213.

[0113] Accordingly, based on the consideration of reducing the possibility of mutual interference between the third sub-receiving coil 1222 and the fourth sub-receiving coil 1223, and thus improving the output accuracy of the second receiving coil 122 for the second induced electrical signal, the circuit board 140 also includes a third dielectric layer 145 located between the third sub-layer 1421 and the fourth sub-layer 1422. For example... Figure 3 As shown, the third sub-layer 1421, the third dielectric layer 145, and the fourth sub-layer 1422 are arranged sequentially along the rotational axis of the rotor 110. For example, the third sub-layer 1421, the third dielectric layer 145, and the fourth sub-layer 1422 are arranged adjacent to each other sequentially along the rotational axis of the rotor 110. The third dielectric layer 145 can be made of an insulating material so that it can be used to provide electrical insulation between the third sub-receiving coil 1222 and the fourth sub-receiving coil 1223.

[0114] Please see Figure 4 , Figure 4 This is a schematic block diagram of the structure of the motor system 10 provided in the embodiments of this application.

[0115] like Figure 4 As shown, the motor system 10 includes a motor 200 and the aforementioned inductive encoder 100. The output information of the inductive encoder 100 can be used to characterize the rotation angle of the motor 200.

[0116] In some embodiments, the motor system 10 includes a motor 200 having a rotating shaft. The motor 200 can drive the rotating shaft to rotate. During the rotation of the rotating shaft of the motor 200, the motor 200 can drive the rotor 110 included in the inductive encoder 100 to rotate via the rotating shaft of the motor 200, thereby the rotation axis of the motor 200 is the same as the rotation axis of the rotor 110 included in the inductive encoder 100.

[0117] For example, the motor system 10 can be applied to applications such as robot dexterous hands, small servo joints, and compact drive systems. For instance, in the application of the motor system 10 to a robot dexterous hand, the motor system 10 can use the motor 200 to drive the robot dexterous hand to rotate, and use the inductive encoder 100 to output information that can characterize the rotation angle of the motor 200. Therefore, the motor system 10 can use the output information of the inductive encoder 100 to characterize the rotation angle of the robot dexterous hand. Of course, the application scenarios of the motor system 10 are not limited to this. For example, the motor system 10 can also be applied to robot rotary joints, automotive steering systems, LiDAR, medical exoskeletons, drone gimbals, and other applications that require controlling the rotation angle of corresponding components; this is not a limitation.

[0118] For a description of the inductive encoder 100 included in the motor system 10 in this embodiment, please refer to the corresponding description of the inductive encoder 100 in the foregoing embodiments, which will not be repeated here.

[0119] The increased integration of the inductive encoder 100, which facilitates its miniaturization, also contributes to the increased integration of the motor system 10, thereby promoting its miniaturization. With the increased integration and miniaturization of the motor system 10, it can be adapted to more small devices and smaller components, thus enhancing its application flexibility.

[0120] In this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features.

[0121] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An inductance encoder characterized in that, include, The rotor is driven to rotate by the shaft of the motor, and the rotor is used to modulate the electromagnetic field provided by the transmitting coil provided on the stator of the inductive encoder. The stator is provided with a transmitting coil, a first receiving coil and a second receiving coil. The transmitting coil is used to provide an electromagnetic field. The first receiving coil is used to sense the electromagnetic field modulated by the rotor to output a first induced electrical signal. The second receiving coil is used to sense the electromagnetic field modulated by the rotor to output a second induced electrical signal. The stator and the rotor are arranged along the rotation axis of the rotor. The first receiving coil and the second receiving coil have different numbers of pole pairs. The first receiving coil and the second receiving coil are arranged along the rotation axis of the rotor and are electrically insulated from each other. The first projection of the first receiving coil on a preset plane and the second projection of the second receiving coil on the preset plane at least partially overlap. The preset plane includes a plane perpendicular to the rotation axis of the rotor.

2. The inductive encoder of claim 1, wherein, The rotor is provided with a conductive pattern. When the rotor rotates, the conductive pattern can change the mutual inductance parameter between the transmitting coil and the first receiving coil, and also change the mutual inductance parameter between the transmitting coil and the second receiving coil, so as to modulate the electromagnetic field provided by the transmitting coil.

3. The inductive encoder of claim 2, wherein, The conductive pattern includes a first conductive pattern and a second conductive pattern. The first conductive pattern includes a first conductive grid, the number of periods of which corresponds to the number of pole pairs of the first receiving coil. The second conductive pattern includes a second conductive grid, the number of periods of which corresponds to the number of pole pairs of the second receiving coil.

4. The inductive encoder according to claim 1, characterized in that, The first receiving coil includes a first-period sinusoidal waveform coil arranged circumferentially along the rotor. The number of periods of the first-period sinusoidal waveform coil corresponds to the number of pole pairs of the first receiving coil. The second receiving coil includes a second-period sinusoidal waveform coil arranged circumferentially along the rotor. The number of periods of the second-period sinusoidal waveform coil corresponds to the number of pole pairs of the second receiving coil. The circle formed by the midpoints of multiple peaks and troughs of the first-period sinusoidal waveform coil is a first circle. The circle formed by the midpoints of multiple peaks and troughs of the second-period sinusoidal waveform coil is a second circle. The first orthographic projection of the first circle onto the preset plane coincides with the second orthographic projection of the second circle onto the preset plane.

5. The inductive encoder according to claim 1, characterized in that, The first receiving coil is positioned closer to the transmitting coil along the rotational axis of the rotor than the second receiving coil, and the first receiving coil has a greater number of pole pairs than the second receiving coil.

6. The inductive encoder according to any one of claims 1 to 5, characterized in that, The stator includes at least two circuit boards, with the first receiving coil and the second receiving coil respectively disposed on different circuit boards.

7. The inductive encoder according to any one of claims 1 to 5, characterized in that, The stator includes at least one circuit board, and the first receiving coil and the second receiving coil are formed on the same circuit board.

8. The inductive encoder according to claim 7, characterized in that, The circuit board includes a first circuit layer, a first dielectric layer and a second circuit layer arranged sequentially along the rotation axis of the rotor. The first receiving coil is formed on the first circuit layer and the second receiving coil is formed on the second circuit layer. The first dielectric layer is used to achieve electrical insulation between the first receiving coil and the second receiving coil.

9. The inductive encoder according to claim 8, characterized in that, The first circuit layer includes a first sub-layer and a second sub-layer, and the first receiving coil includes a first sub-receiving coil and a second sub-receiving coil. The first sub-receiving coil is formed on the first sub-layer, and the second sub-receiving coil is formed on the second sub-layer. The second circuit layer includes a third sub-layer and a fourth sub-layer, and the second receiving coil includes a third sub-receiving coil and a fourth sub-receiving coil, wherein the third sub-receiving coil is formed on the third sub-layer and the fourth sub-receiving coil is formed on the fourth sub-layer; The circuit board further includes a second dielectric layer located between the first sub-layer and the second sub-layer, and a third dielectric layer located between the third sub-layer and the fourth sub-layer. The second dielectric layer is used to provide electrical insulation between the first sub-receiving coil and the second sub-receiving coil, and the third dielectric layer is used to provide electrical insulation between the third sub-receiving coil and the fourth sub-receiving coil.

10. A motor system, characterized in that, The motor system includes a motor and an inductive encoder as described in any one of claims 1 to 9, wherein the output information of the inductive encoder can be used to characterize the rotation angle of the motor.

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