Capacitive encoders, electronic equipment

Abstract

The present application relates to the technical field of encoders, and discloses a capacitive encoder and an electronic device. The capacitive encoder of the present application includes: a circuit board, a conductor plate; the conductor plate is arranged opposite to the first surface of the circuit board; the first surface of the circuit board includes a first electrode area, a second electrode area, and a third electrode area; a first electrode is provided on the first electrode area; the second electrode area includes N first areas, each of which is provided with M second electrodes, N is an integer greater than 1, and M is an integer greater than 1; the third electrode area includes N second areas, and the second area is divided into P sub-areas; P is an integer greater than 1; the state of each sub-area is the first state or the second state; the states of the P sub-areas of each second area constitute the identification of the second area, and the identification of each second area is different, thereby taking into account both the accuracy and cost of encoder detection.

Description

Technical Field

[0001] The present application relates to the technical field of encoders, and in particular to a capacitive encoder and an electronic device. Background Art

[0002] Currently, conventional encoders include photoelectric encoders and magnetoelectric encoders. Photoelectric encoders measure position or angle by detecting whether light passes through a grating. However, low-end photoelectric encoders have low accuracy, while high-end photoelectric encoders are very expensive, making it difficult to balance cost and accuracy. Magnetoelectric encoders measure position through the interaction between magnetic materials and magnetically sensitive elements, such as Hall effect sensors or magnetoresistive elements. However, electromagnetic encoders are susceptible to external magnetic interference, resulting in low detection accuracy.

[0003] Therefore, conventional encoders cannot achieve both detection accuracy and cost. Summary of the Invention

[0004] The purpose of the embodiments of the present application is to provide a capacitive encoder and an electronic device, thereby taking into account both the accuracy and cost of encoder detection.

[0005] To solve the above technical problems, an embodiment of the present application provides a capacitive encoder, comprising: a circuit board, a conductor plate; the conductor plate is arranged opposite to the first surface of the circuit board; the first surface of the circuit board includes a first electrode area, a second electrode area arranged around the edge of the first electrode area, and a third electrode area arranged around the second electrode area along an edge away from the first electrode area; a first electrode is arranged on the first electrode area; the second electrode area includes N first areas, each of which is provided with M second electrodes, and the second electrode extends from the first edge of the second electrode area close to the first electrode area to the second edge of the second electrode area close to the third electrode area; N is an integer greater than 1, and M is an integer greater than 1; the third electrode area includes N second areas, The second region extends from the third edge of the third electrode plate region close to the second electrode plate region to the fourth edge of the third electrode plate region away from the second electrode plate region; the second region is divided into P sub-regions, and the P sub-regions of the second region gradually move away from the second electrode plate region in sequence; P is an integer greater than 1; the state of each sub-region is the first state or the second state, the first state is that the third electrode plate is provided on the sub-region, and the second state is that the third electrode plate is not provided on the sub-region; the state of each of the P sub-regions of the second region constitutes the identification of the second region, and the identification of each second region is different; wherein, during the rotation of the conductor plate, the overlapping area of ​​the conductor plate and the first region changes, and the overlapping area of ​​the conductor plate and the second region changes.

[0006] An embodiment of the present application further provides an electronic device, comprising: a motor shaft, and the capacitive encoder as described above; the conductor plate is arranged on an extension section of the motor shaft.

[0007] In some embodiments, the conductor plate includes a first conductor plate, K second conductor plates extending from the first conductor plate, and a third conductor plate extending from the second conductor plate in a direction away from the first conductor plate; K is an integer greater than or equal to 1; the first conductor plate is arranged opposite to the first electrode plate, the second conductor plate is arranged opposite to the first area of ​​the second electrode plate area, and the third conductor plate is arranged opposite to the second area of ​​the third electrode plate area.

[0008] In some embodiments, the value of K is the same as the value of N; and in the rotation direction of the conductor plate, the width of the second conductor plate is smaller than the width of the first region.

[0009] In some embodiments, M is 5; the M second pole plates have the same size and shape; in the rotation direction of the conductor plate, the width of the second conductor plate is equal to the width of the two second pole plates in the second region.

[0010] In some embodiments, the number of the third conductor plate is one; the third conductor plate has the same shape and size as the second region.

[0011] In some embodiments, a grounding area is provided between the first electrode area and the second electrode area, and a grounding plate is provided on the grounding area; the grounding area is provided around the edge of the first electrode area, and the second electrode area is provided around the grounding area away from the edge of the first electrode area.

[0012] In some embodiments, a projection of the first plate region on the first surface is circular.

[0013] In some embodiments, the P and N satisfy the following relationship: P≥log2N.

[0014] In some embodiments, N is 8, P is 3, and the third conductor plate extends from two adjacent second conductor plates.

[0015] The technical solution provided by the embodiments of the present application has at least the following advantages:

[0016] Through the above-mentioned structure, this embodiment can determine the identification of the second area where the conductor plate is located based on the capacitance formed by the first electrode plate and the third electrode plate under the action of the conductor plate, and the position range of the conductor plate can be determined based on the identification. The specific rotation angle of the conductor plate within the position range can be further determined based on the capacitance formed by the first electrode plate and the second electrode plate under the action of the conductor plate, thereby achieving the accuracy of encoder detection at a lower cost, taking into account both the accuracy and cost of encoder detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] One or more embodiments are exemplarily illustrated by pictures in the corresponding drawings. These exemplifications do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings are represented as similar elements. Unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0018] Figure 1 is a structural diagram of a capacitive encoder according to an embodiment of the present application;

[0019] Figure 2 This is a schematic diagram of the structure of the circuit board divided into various areas according to an embodiment of the present application;

[0020] Figure 3is a schematic structural diagram of a circuit board according to an embodiment of the present application;

[0021] Figure 4 Schematic diagram of the principle of forming a first capacitor by the first plate and the second plate under the action of the conductor plate;

[0022] Figure 5 It is a schematic diagram of the principle of the first plate and the third plate forming a second capacitor under the action of the conductor plate;

[0023] Figure 6 is another structural schematic diagram of a circuit board according to an embodiment of the present application;

[0024] Figure 7 is a schematic diagram of the specific structure of a circuit board according to an embodiment of the present application;

[0025] Figure 8 is a schematic diagram of a specific equivalent structure of a capacitive encoder according to an embodiment of the present application;

[0026] Figure 9 is a schematic structural diagram of a conductor plate according to an embodiment of the present application;

[0027] Figure 10 2 is another structural schematic diagram of a circuit board according to an embodiment of the present application. DETAILED DESCRIPTION

[0028] As known from the background art, conventional encoders cannot take into account both detection accuracy and cost.

[0029] In order to solve the technical problem that conventional encoders cannot achieve both detection accuracy and cost, the embodiments of the present application provide a capacitive encoder, comprising a circuit board and a conductor plate; the conductor plate is arranged opposite to a first surface of the circuit board; the first surface of the circuit board includes a first electrode region, a second electrode region arranged around an edge of the first electrode region, and a third electrode region arranged around the second electrode region along an edge away from the first electrode region; a first electrode plate is arranged on the first electrode region; the second electrode region includes N first regions, each of which is provided with M second electrodes, the second electrode plate extending from a first edge of the second electrode region near the first electrode region to a second edge of the second electrode region near the third electrode region; N is an integer greater than 1, and M is an integer greater than 1; The third electrode plate region includes N second regions, and the second region extends from a third edge of the third electrode plate region close to the second electrode plate region to a fourth edge of the third electrode plate region away from the second electrode plate region; the second region is divided into P sub-regions, and the P sub-regions of the second region gradually move away from the second electrode plate region in sequence; P is an integer greater than 1; the state of each sub-region is a first state or a second state, the first state is that a third electrode plate is provided on the sub-region, and the second state is that no third electrode plate is provided on the sub-region; the state of the P sub-regions of each second region constitutes an identification of the second region, and the identification of each second region is different; wherein, during the rotation of the conductor plate, the overlapping area of ​​the conductor plate and the first region changes, and the overlapping area of ​​the conductor plate and the second region changes.

[0030] Through the above-mentioned structure, this embodiment can determine the identification of the second area where the conductor plate is located based on the capacitance formed by the first electrode plate and the third electrode plate under the action of the conductor plate, and the position range of the conductor plate can be determined based on the identification. The specific rotation angle of the conductor plate within the position range can be further determined based on the capacitance formed by the first electrode plate and the second electrode plate under the action of the conductor plate, thereby achieving the accuracy of encoder detection at a lower cost, taking into account both the accuracy and cost of encoder detection.

[0031] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, each embodiment of the present application will be described in detail below with reference to the accompanying drawings. However, it will be understood by those skilled in the art that in each embodiment of the present application, many technical details are proposed to enable the reader to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in the present application can be implemented. The division of the following embodiments is for convenience of description and should not constitute any limitation on the specific implementation of the present application. The various embodiments can be combined and referenced with each other under the premise of no contradiction.

[0032] An embodiment of the present application relates to a capacitive encoder, such as Figure 1 As shown in FIG. , it is a schematic diagram of the structure of the capacitive encoder of this embodiment. Figure 2 As shown in FIG. 1 , it is a schematic diagram of the structure of the circuit board of this embodiment, wherein each area is divided into Figure 3 The figure shows the structure of the circuit board of this embodiment. Figure 2 The dotted lines in the figure divide the circuit board into a first plate area 11, a second plate area 12, a third plate area 13, and a grounding area 14. Figure 2 This is only to show the division of the first plate area 11, the second plate area 12, the third plate area 13, and the grounding area 14 on the circuit board. The corresponding plates are not marked. For details on the marking of each plate, see Figure 3 .

[0033] The capacitive encoder of this embodiment includes a circuit board 1 and a conductor plate 2 .

[0034] Specifically, the first surface of the circuit board 1 includes a first plate region 11 , a second plate region 12 arranged around an edge of the first plate region 11 , and a third plate region 13 arranged around the second plate region 12 along an edge away from the first plate region 11 .

[0035] Specifically, a first electrode plate 111 is provided on the first electrode plate region 11; the second electrode plate region 12 includes N first regions 120, and each first region 120 is provided with M second electrode plates 121, and the second electrode plate 121 extends from the first edge of the second electrode plate region 12 close to the first electrode plate region 11 to the second edge of the second electrode plate 121 close to the third electrode plate region 13, that is, each second electrode plate 121 extends from the first edge of the second electrode plate region 12 to the second edge of the second electrode plate region 12, wherein the first edge is the edge of the second electrode plate region 12 close to the first electrode plate region 11, and the second edge is the edge of the second electrode plate region 12 close to the third electrode plate region 13; N is an integer greater than 1, and M is an integer greater than 1.

[0036] It should be noted that the figure takes N as 8 and M as 5 as an example for illustration. In actual applications, N can be 2, 3, 4, 5, 6, 7, 8, etc., and M can be 2, 3, 4, 5, etc., which are set according to actual needs and are not specifically limited in this embodiment.

[0037] Specifically, the third electrode region 13 includes N second regions 130, and the second region 130 extends from the third edge of the third electrode region 13 close to the second electrode region 12 to the fourth edge of the third electrode region 13 away from the second electrode region 12, that is, each second region 130 extends from the third edge of the third electrode region 13 to the fourth edge of the third electrode region 13, wherein the third edge is the edge of the third electrode region 13 close to the second electrode region 12, and the fourth edge is the edge of the third electrode region 13 away from the second electrode region 12.

[0038] Specifically, the second region 130 is divided into P sub-regions 132, and the P sub-regions 132 of the second region 130 gradually move away from the second electrode region 12 in sequence; P is an integer greater than 1; the state of each sub-region 132 is a first state or a second state, the first state is that a third electrode 131 is provided on the sub-region 132, and the second state is that the third electrode 131 is not provided on the sub-region 132; the state of the P sub-regions 132 of each second region 130 constitutes the identification of the second region 130, and the identification of each second region 130 is different.

[0039] Specifically, in this embodiment, the conductive plate 2 is disposed opposite the first surface of the circuit board 1. During the rotation of the conductive plate 2, the overlapping area between the conductive plate 2 and the first region 120 changes, and the overlapping area between the conductive plate 2 and the second region 130 changes. The conductive plate 2 rotates along the central axis of the first plate region 11, which is a line perpendicular to the first plate region 11 and intersecting the center point of the first plate region 11.

[0040] Through the above-mentioned structure, this embodiment can determine the identification of the second area 130 where the conductor plate 2 is located based on the capacitance formed by the first electrode 111 and the third electrode 131 under the action of the conductor plate 2, and the position range of the conductor plate 2 can be determined based on the identification. The specific rotation angle of the conductor plate 2 within the position range can be further determined based on the capacitance formed by the first electrode 111 and the second electrode 121 under the action of the conductor plate 2, thereby achieving the accuracy of encoder detection at a lower cost, taking into account both the accuracy and cost of encoder detection.

[0041] Specifically, the encoder of this embodiment uses a capacitive encoder, a new type of encoder that can arrange both the emitter plate and the receiver plate on the same circuit board 1, and arrange the conductor plate 2 on the extension of the motor shaft. The emitter plate is coupled to the receiver plate via a floating conductive sheet to form a capacitor. When the conductor plate 2 rotates with the motor, that is, when the motor shaft rotates, the conductor plate 2 rotates along with it, and the area directly opposite the conductor plate 2 and the emitter plate and receiver plate changes, causing a change in capacitance. Therefore, by detecting the capacitance value, the absolute position of the current shaft can be fed back.

[0042] The first electrode plate 111 and the second electrode plate 121 of this embodiment form a first capacitor under the action of the conductor plate 2. Figure 4As shown, it is a schematic diagram of the principle of the first plate and the second plate forming the first capacitor under the action of the conductor plate, wherein the first plate 111 is used as the emitter plate and the second plate 121 is used as the receiving plate for explanation. The electric field lines between the first plate 111, the second plate 121 and the conductor plate 2 first pass through the first plate 111 to the conductor plate 2, and then to the second plate 121, so that the first plate 111 and the second plate 121 are coupled through the conductor plate 2 to form the first capacitor.

[0043] The first electrode plate 111 and the third electrode plate 131 of this embodiment form a second capacitor under the action of the conductor plate 2. Figure 5 As shown, it is a schematic diagram of the principle of the first plate and the third plate forming a second capacitor under the action of the conductor plate, wherein the first plate 111 is used as the emitter plate and the third plate 131 is used as the receiving plate for explanation. The electric field lines between the first plate 111, the third plate 131 and the conductor plate 2 first pass through the first plate 111 to the conductor plate 2, and then to the third plate 131, so that the first plate 111 and the third plate 131 are coupled through the conductor plate 2 to form a second capacitor.

[0044] Specifically, in this embodiment, the identifier of the second area 130 where the conductor plate 2 is located can be determined based on the size of the second capacitor, and the position range of the conductor plate 2 can be determined based on the identifier. Thereafter, the specific rotation angle of the conductor plate 2 within the position range can be further determined based on the size of the first capacitor, thereby achieving the accuracy of encoder detection at a lower cost, taking into account both the accuracy and cost of encoder detection.

[0045] In some embodiments, the N first regions 120 have the same size and shape. By setting the N first regions 120 to be identical, this embodiment improves the accuracy of the obtained rotation angle of the conductor plate 2 when the specific rotation angle of the conductor plate 2 within the position range can be further determined based on the magnitude of the first capacitance, thereby improving the accuracy of encoder detection.

[0046] In some embodiments, the N second regions 130 have the same size and shape. In this embodiment, by setting the N second regions 130 to be identical, the second plate region 12 is divided into multiple identical position ranges. Since each second region 130 corresponds to a different identifier, when determining the identifier of the second region 130 where the conductor plate 2 is located based on the magnitude of the second capacitance, the angular range of the conductor plate 2 can be limited to a specific position range, thereby improving the accuracy of encoder detection.

[0047] like Figure 2 、 Figure 3As shown, the projection of the first plate region 11 on the first surface is circular. That is, the first plate region 11 is circular, the second plate region 12 is a circular ring structure surrounding the first plate region 11, and the third plate region 13 is a circular ring structure surrounding the second plate region 12. Through this arrangement, the shapes and sizes of the multiple first regions 120 in the second plate region 12 can be set to be exactly the same, and the shapes and sizes of the second plates 121 arranged in the first regions 120 can also be set to be exactly the same, thereby improving the accuracy of the detection of the rotation angle of the conductor plate 2 and improving the accuracy of the encoder detection.

[0048] Specifically, the first electrode region 11 of this embodiment is circular, and a first electrode plate 111 is provided on the first electrode region 11. The first electrode plate 111 can be set to be circular or other shapes, as long as the conductor plate 2 can always cover the first electrode plate 111 during the rotation process.

[0049] like Figure 2 As shown, a grounding region 14 is provided between the first electrode region 11 and the second electrode region 12 of this embodiment, and a grounding plate is provided on the grounding region 14; Figure 6 FIG. 1 is another structural diagram of the circuit board of this embodiment. Figure 2 、 Figure 6 The middle dashed line marks the grounding region 14 and the grounding plate 141. In this embodiment, the grounding region 14 is disposed between the first plate region 11 and the second plate region 12, and the grounding plate 141 is disposed on the grounding region 14. The grounding region 14 is disposed around the edge of the first plate region 11, and the second plate region 12 is disposed around the grounding region 14, away from the edge of the first plate region 11. In this embodiment, by disposing the grounding region 14 between the first plate region 11 and the second plate region 12, the grounding plate 141 is disposed between the first plate 111 and the second plate 121, isolating the first plate 111 and the second plate 121. This prevents direct coupling of signals between the first plate 111 and the second plate 121, improves the accuracy of signal acquisition, and enhances the accuracy of encoder detection.

[0050] Specifically, in the rotational direction of the conductor plate 2, the width of the second conductor plate 22 is smaller than the width of the first region 120. In this embodiment, by setting the width of the second conductor plate 22 to be smaller, when the conductor plate 2 rotates along the central axis of the first electrode region 11, the first capacitance formed between the second conductor plate 22 and the corresponding second electrode plate 121 in the first region 120 changes. The magnitude of the first capacitance can be used to further determine the specific rotation angle of the conductor plate 2, thereby improving the accuracy of encoder detection.

[0051] In some embodiments, within a second region 130, the M second electrodes 121 have the same size and shape. In this embodiment, the value of M can be 5, or 3, 4, 6, etc., wherein, in the rotation direction of the conductor plate 2, the width of the second conductor plate 22 is equal to the width of the two second electrodes 121 in the second region 130; that is, the second conductor plate 22 covers the two second electrodes 121 within a second region 130. In this way, during the rotation of the second conductor plate 22, the first capacitance formed by the second conductor plate 22 and one of the second electrodes 121 gradually increases, and the first capacitance formed by the second conductor plate 22 and the other second electrodes 121 gradually decreases. By the change in the capacitance formed between the second conductor plate 22 and the multiple second electrodes 121, the angle information of the rotation of the conductor plate 2 can be more clearly determined, thereby improving the detection accuracy.

[0052] The following is an example of the simulation part of this embodiment, without limiting the implementation details of this embodiment.

[0053] like Figure 7 As shown, it is a schematic diagram of the specific structure of the circuit board of this embodiment, wherein the edge of the first electrode area 11 is periodically distributed with 8 first areas 120, each first area 120 covers a 45-degree area, wherein each first area 120 is provided with 5 fan-shaped second electrodes 121, namely Rx1, Rx2, Rx3, Rx4, and Rx5, respectively. In the next 45-degree area, the 5 fan-shaped second electrodes 121 of each first area 120 are also arranged periodically according to Rx1, Rx2, Rx3, Rx4, and Rx5. The 5 second electrodes 121 of each first area 120, namely Rx1, Rx2, Rx3, Rx4, and Rx5, are coupled with the first electrode 111 through the conductor plate 2 to form a first capacitor, which can be marked as C1, C2, C3, C4, and C5 respectively. Thus, the specific rotation angle of the conductor can be determined by the changes in the multiple first capacitors, thereby improving the accuracy of the encoder detection.

[0054] In order to better illustrate the principle, the above structure is simplified to some extent, from rotation to translation, and then the first electrode 111 is equivalent to some parts. The specific equivalent structure diagram of the capacitive encoder is as follows: Figure 8 As the conductor plate 2 moves to the left, the area facing one Rx3 increases, and the corresponding capacitance C3 increases, while the area facing the other Rx1 decreases, and the corresponding capacitance C1 decreases. By detecting the size of the capacitance value, the rotation angle of the conductor plate 2 can be detected.

[0055] Due to the array repetition relationship between the above structures, for the same group of capacitance signals, namely C1, C2, C3, C4, and C5, there are multiple different positions that meet the conditions. That is, there are 8 groups of Rx1, Rx2, Rx3, Rx4, and Rx5 in the figure, and 8 positions can be determined. Then, combined with the combined digital signal of the third electrode area, it can be determined in which sector, thereby achieving the accuracy of angle detection.

[0056] like Figure 9 , which is a schematic structural diagram of the conductor plate of this embodiment. Specifically, the conductor plate 2 of this embodiment is a metal plate, which can realize the function of coupling the emitter plate and the receiver plate to form a capacitor.

[0057] The conductor plate 2 of this embodiment includes a first conductor plate 21, K second conductor plates 22 extending from the first conductor plate 21, and a third conductor plate 23 extending from the second conductor plate 22 in a direction away from the first conductor plate 21. K is an integer greater than or equal to 1. The first conductor plate 21, the second conductor plate 22, and the third conductor plate 23 are integrally formed.

[0058] It should be noted that Figure 9 、 Figure 3 In the figure, K is 8 and N is also 8 as an example. In actual applications, N can be 2, 3, 4, 5, 6, 7, 8, etc., and K can be 1, 2, 3, 4, 5, 6, 7, 8, etc. N and K can be the same or different, and are set according to actual needs. This embodiment does not make any specific limitations.

[0059] Specifically, the first conductor plate 21, the second conductor plate 22, and the third conductor plate 23 all cover different areas, wherein the first conductor plate 21 is arranged opposite to the first electrode plate 111, the second conductor plate 22 is arranged opposite to the first area 120 of the second electrode area 12, and the third conductor plate 23 is arranged opposite to the second area 130 of the third electrode area 13.

[0060] like Figure 9 As shown, the third conductor plate 23 extends from two adjacent second conductor plates 22. If the third conductor plate 23 extends from only one of the second conductor plates 22, the end of the third conductor plate 23 not connected to the second conductor plate 22 may be closer to the circuit board 1 due to the weight of the third conductor plate 23 itself, which not only affects the detection accuracy, but in more serious cases, may also cause the third conductor plate 23 to directly contact the circuit board 1, affecting the performance of the circuit board 1. Therefore, in this embodiment, the third conductor plate 23 extends from two adjacent second conductor plates 22, and is jointly supported by the two second conductor plates 22. This improves the stability of the third conductor plate 23, improves the accuracy of the detection of the rotation angle of the conductor plate 2, improves the accuracy of the encoder detection, and prevents damage to the circuit board 1.

[0061] In some embodiments, the value of K is the same as the value of N; for example, N and K are both 2, 3, 4, 5, 6, 7, 8, etc. In this embodiment, by setting K and N to the same value, during the rotation of the conductor plate 2, the K second conductor plates 22 correspond to the N second regions 130 one-to-one. One second conductor plate 22 and one corresponding second region 130 can determine a rotation angle of the conductor plate 2. By combining multiple rotation angles, more accurate rotation angle information of the conductor plate 2 can be determined, thereby improving the detection accuracy of the encoder.

[0062] In some embodiments, the number of the third conductor plate 23 is one; the third conductor plate 23 has the same shape and size as the second region 130. Figure 9 As shown, the number of the third conductor plate 23 is one. In this embodiment, the identifier of the only second region 130 can be determined according to the size of the second capacitor, and the precise position range of the conductor plate 2 can be determined according to the identifier.

[0063] To describe the implementation principle of this embodiment in more detail, the following is an example in which P is 3, K is 8, and N is 8.

[0064] Specifically, the second area 130 is the digital part of this embodiment. Each second area 130 covers a 45-degree area. Each second area 130 is provided with three sub-areas 132 arranged from the inside to the outside. The way of setting the third electrode 131 on the three sub-areas 132 of each second area 130 is different. There are a total of 8 combinations. If the sub-area 132 is provided with the third electrode 131, the first state is 1, and the sub-area 132 is not provided with the third electrode 131, which corresponds to the second state is 0. The states of the three sub-areas 132 constitute the identification of the second area 130, which is a 3-bit digital signal. The 3-bit digital signal is arranged in order from the inside to the outside of the sub-area 132, and the identification corresponding to the 8 combinations is 000, 001, 010, 011, 100, 101, 110, and 111.

[0065] It should be noted that to ensure that each second region 130 corresponds to a unique identifier, the following relationship is satisfied between P and N: P ≥ log2N. When N is 8, the minimum setting for P is 3, and P can also be set to 4, 5, 6, and so on. For example, when P is set to 4, the states of the four sub-regions 132 can theoretically constitute 16 identifiers, each of which is a 4-bit digital signal. In this case, 8 identifiers can be selected from the 16 identifiers for use.

[0066] Specifically, when the third conductor plate 23 covers a second area 130, the second capacitance generated by the three sub-areas 132 in the second area 130 can be obtained to determine the second area 130 covered by the third conductor plate 23, that is, to determine whether the conductor plate 2 is within the angular range of the second area 130. Figure 10 , which is another structural schematic diagram of the circuit board of this embodiment, in the figure, three second regions 130 , namely region 1 , region 2 , and region 3 , are marked in the second region 130 of the third electrode region 13 .

[0067] For example, the conductive plate 2 first rotates to an area 1. Since the third electrode 131 is not provided in the three sub-areas 132 within the second area 130, the identifier corresponding to the second area 130 is 000. When the conductive plate 2 rotates to the area 1, the second capacitance obtained at this time is almost 0. It can be considered that the combined digital signal at this time is 000. By matching the combined digital signal 000 with the identifier 200 of the area 1, it can be determined that the conductive plate 2 has rotated to the position range of the area 1 at this time.

[0068] Similarly, assuming that the conductive plate 2 rotates to area 2, and the three sub-areas 132 of a second area 130 from the inside to the outside have the third electrode 131 set in the states of set, not set, and not set, respectively, then the identifier corresponding to this second area 130 is 100. When the third conductive plate 23 covers the second area 130, the sub-area 132 with the third electrode 131 generates a second capacitance, and the recorded digital signal is 1. The sub-area 132 without the third electrode 131 does not generate a second capacitance, and the recorded digital signal is 0, thereby obtaining a combined digital signal of 100. By matching the combined digital signal 100 with the identifier 100 of area 2, it can be determined that the conductive plate 2 has now rotated to within the position range of area 2.

[0069] Similarly, assuming that the conductive plate 2 rotates to area 3, and the three sub-areas 132 of a second area 130 from the inside to the outside are provided with the third electrode 131 in the states of "set", "set", and "set" respectively, then the corresponding identifier of this second area 130 is 111. When the third conductive plate 23 covers the second area 130, the sub-area 132 provided with the third electrode 131 generates a second capacitance, and the recorded digital signal is 1, thereby obtaining a combined digital signal of 111. By matching the combined digital signal 111 with the identifier 111 of area 3, it can be determined that the conductive plate 2 has now rotated to within the position range of area 3.

[0070] After determining the area where the conductor plate 2 is located, this embodiment can accurately determine the rotation angle of the conductor plate 2 in combination with the data of the above simulation part, thereby improving the detection accuracy of the encoder.

[0071] It should be noted that during the rotation of the conductor plate 2, the third conductor plate 23 may simultaneously cover two adjacent second areas 130. At this time, a combined digital signal corresponding to the two second areas 130 may be obtained. In order to ensure that the obtained combined digital signal is unique, it can be set that when two combined digital signals are obtained, a combined digital signal can be determined with reference to the time when the two combined digital signals are generated. For example, the combined digital signal with the earliest or latest generation time is selected, and the rotation position range of the conductor plate 2 is determined based on the second area 130 corresponding to the combined digital signal.

[0072] Specifically, based on the conventional capacitive encoder, this embodiment makes the second electrode plate 121 cycle periodically along the circumference, for example Figure 3 、 Figure 7 As shown, the circuit is cycled eight times to form eight periodic sectors, i.e., eight periodic first regions 120. On this basis, according to the logic of digital signal design, eight second regions 130 are designed around the eight periodic second regions 130. The sector to which the conductor plate 2 is currently rotated is determined based on the combined digital signals corresponding to the second regions 130. Through this combination of analog and digital, the detection accuracy is effectively improved without substantially increasing the cost, and both the accuracy and cost of encoder detection are taken into account.

[0073] On the other hand, an embodiment of the present application further provides an electronic device, comprising: a motor shaft, a capacitive encoder as described above; and a conductor plate disposed on an extension section of the motor shaft.

[0074] It is not difficult to find that this embodiment is an electronic device embodiment corresponding to the embodiment, and this embodiment can be implemented in conjunction with the above embodiment. The relevant technical details mentioned in the above embodiment are still valid in this embodiment, and to reduce repetition, they are not repeated here. Accordingly, the relevant technical details mentioned in this embodiment can also be applied to the above embodiment.

[0075] In addition, in order to highlight the innovative part of this application, this embodiment does not introduce units that are not closely related to solving the technical problems raised by this application, but this does not mean that there are no other units in this embodiment.

[0076] The division of various components above is only for the purpose of clear description. During implementation, they can be combined into one component or some components can be split and decomposed into multiple components. As long as they include the same logical relationship, they are all within the scope of protection of this application.

[0077] Those skilled in the art will appreciate that the above embodiments are specific embodiments for implementing the present application, and that in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present application.

Claims

1. A capacitive encoder, characterized in that: include: Circuit boards, conductor boards; The conductive plate is disposed opposite to the first surface of the circuit board; the first surface of the circuit board includes a first plate region, a second plate region disposed around an edge of the first plate region, and a third plate region disposed around the second plate region and along an edge away from the first plate region; The first electrode region is provided with a first electrode plate; the second electrode region includes N first regions, each of which is provided with M second electrode plates, and the second electrode plate extends from a first edge of the second electrode region close to the first electrode region to a second edge of the second electrode plate close to the third electrode region; N is an integer greater than 1, and M is an integer greater than 1; The third electrode region includes N second regions, and the second region extends from a third edge of the third electrode region close to the second electrode region to a fourth edge of the third electrode region away from the second electrode region; the second region is divided into P sub-regions, and the P sub-regions of the second region are gradually away from the second electrode region in sequence; P is an integer greater than 1; the state of each sub-region is a first state or a second state, the first state is that the third electrode plate is provided on the sub-region, and the second state is that the third electrode plate is not provided on the sub-region; the states of the P sub-regions of each second region constitute an identifier of the second region, and the identifier of each second region is different; During the rotation of the conductor plate, the overlapping area between the conductor plate and the first area changes, and the overlapping area between the conductor plate and the second area changes.

2. The capacitive encoder according to claim 1, wherein: The conductor plate includes a first conductor plate, K second conductor plates extending from the first conductor plate, and a third conductor plate extending from the second conductor plate in a direction away from the first conductor plate; K is an integer greater than or equal to 1; The first conductor plate is disposed opposite to the first electrode plate, the second conductor plate is disposed opposite to the first region of the second electrode plate region, and the third conductor plate is disposed opposite to the second region of the third electrode plate region.

3. The capacitive encoder according to claim 2, wherein: The value of K is the same as the value of N; in the rotation direction of the conductor plate, the width of the second conductor plate is smaller than the width of the first region.

4. The capacitive encoder according to claim 3, wherein: The M is 5; the M second electrode plates are of the same size and shape; In the rotation direction of the conductor plate, the width of the second conductor plate is equal to the width of the two second pole plates in the second region.

5. The capacitive encoder according to claim 2, wherein: The number of the third conductor plate is one; the third conductor plate has the same shape and size as the second region.

6. The capacitive encoder according to claim 1, wherein: A grounding area is provided between the first electrode area and the second electrode area, and a grounding plate is provided on the grounding area; The grounding region is arranged around an edge of the first electrode region, and the second electrode region is arranged around an edge of the grounding region away from the first electrode region.

7. The capacitive encoder according to any one of claims 1 to 6, characterized in that: The projection of the first electrode region on the first surface is circular.

8. The capacitive encoder according to any one of claims 1 to 6, characterized in that: The P and the N satisfy the following relationship: P≥log2N.

9. The capacitive encoder according to claim 3, wherein: The N is 8, the P is 3; the third conductor plate extends from two adjacent second conductor plates.

10. An electronic device, characterized in that: include: A motor shaft, a capacitive encoder according to any one of claims 1 to 8; The conductor plate is arranged on an extension section of the motor shaft.

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