Capacitive displacement detection structure and electronic device

Abstract

This application relates to the field of displacement detection and discloses a capacitive displacement detection structure and electronic device. In the capacitive displacement detection structure, both the emitting and receiving plates are disposed on the stator, and a floating plate is disposed on the mover. The receiving plate includes a first sub-plate and a second sub-plate. The emitting plate, the first sub-plate, and multiple second sub-plates constitute a detection unit. The second sub-plates are periodically arranged, and second sub-plates at the same position in different periods are connected to the same circuit channel. The first sub-plate is positioned opposite to all the second sub-plates arranged in one period. The floating plate moves synchronously with the mover, and in any state during the movement, the facing area between the floating plate and the emitting plate is always the same, and the floating plate has a facing area with at least two second sub-plates. Thus, by changing the arrangement of the receiving and emitting plates based on a limited number of circuit channels, accurate detection over a longer stroke can be achieved.

Description

Technical Field

[0001] This application relates to the field of displacement detection, and in particular to a capacitive displacement detection structure and electronic device. Background Technology

[0002] Currently, displacement detection can be achieved in electronic devices by constructing capacitor cells. Constructing a capacitor cell typically requires a transmitting electrode and a corresponding receiving electrode. The detected displacement distance is related to the length covered by the receiving electrode. To increase the coverage length of the receiving electrode, the area of ​​the receiving electrode or the number of receiving electrodes is usually increased.

[0003] However, due to space limitations on the moving part of the device, there are limitations to increasing the area of ​​the receiving electrode. Unrestricted increase in the area of ​​the receiving electrode will lead to inaccurate detection results. Furthermore, the limited number of circuit channels in electronic devices limits the number of receiving electrodes that can be installed. If the number of receiving electrodes exceeds the number of circuit channels, the signals from the excess receiving electrodes cannot be received, rendering them ineffective and preventing accurate displacement detection. Utility Model Content

[0004] The purpose of this application is to provide a capacitive displacement detection structure and electronic device that, based on a limited circuit channel, achieves accurate detection over a longer stroke by changing the arrangement of the receiving and transmitting plates.

[0005] To address the aforementioned technical problems, embodiments of this application provide a capacitive displacement detection structure, comprising: a mover, a stator, an emitting electrode plate, a receiving electrode plate, and a floating electrode plate; the emitting electrode plate and the receiving electrode plate are both disposed on the stator, and the floating electrode plate is disposed on the mover; the receiving electrode plate includes: a first sub-electrode plate and a second sub-electrode plate; the emitting electrode plate, the first sub-electrode plate, and a plurality of second sub-electrode plates constitute a detection unit, wherein the second sub-electrode plates in the detection unit are periodically arranged, and second sub-electrode plates at the same position in different periods are connected to the same circuit channel, and the first sub-electrode plate is disposed opposite to all the second sub-electrode plates arranged in one period; the floating electrode plate moves synchronously with the mover, and in any state during the movement of the floating electrode plate, the facing area between the floating electrode plate and the emitting electrode plate is always the same, and the floating electrode plate has a facing area with at least two second sub-electrode plates.

[0006] Embodiments of this application also provide an electronic device, including the capacitive displacement detection structure described above.

[0007] Compared to related technologies, in this embodiment of the application, in a structure where the mover displaces relative to the stator in a device, to detect the distance the mover moves, an emitting electrode plate and a receiving electrode plate are provided on the stator, and a floating electrode plate is provided on the mover. The arrangement of the receiving electrode plates is changed, dividing the receiving electrode plate into a first sub-electrode plate and a second sub-electrode plate. The emitting electrode plate, the first sub-electrode plate, and multiple second sub-electrode plates constitute a detection unit. The second sub-electrode plates in the detection unit are arranged periodically, and second sub-electrode plates at the same position in different periods are connected to the same circuit channel. The first sub-electrode plate is positioned opposite to all the second sub-electrode plates arranged in one period. The floating electrode plate moves synchronously with the mover, and in any state during the movement, the facing area of ​​the floating electrode plate and the emitting electrode plate is always the same. The floating plate and at least two second sub-plates have a directly opposite area. Based on the capacitance between the floating plate and the second sub-plates, the position of the floating plate and the position of the second sub-plates in each cycle can be determined. Based on the capacitance between the floating plate and the first sub-plate, the cycle in which the floating plate moves to the distribution of the second sub-plates can be determined. By combining the values ​​of both types of capacitance, the position of the floating plate can be accurately obtained. Since the floating plate moves synchronously with the mover, the movement distance of the mover can be determined based on the position of the floating plate. In the above structure, the second sub-plates at the same position in different cycles are connected to the same circuit channel, saving the number of circuit channels occupied by the receiving plate. With a limited number of circuit channels, accurate detection over a longer distance can be achieved.

[0008] In addition, when there are multiple detection units, the receiving electrode plate further includes a third sub-electrode plate; the third sub-electrode plate is disposed opposite to at least one of the detection units, and the direction in which the third sub-electrode plate is opposite to the detection unit is the same as the direction in which the first sub-electrode plate is opposite to the second sub-electrode plate.

[0009] In addition, the transmitting electrode and the receiving electrode are on the same plane.

[0010] In addition, the second sub-electrode plates all have the same shape.

[0011] In addition, when the length of the floating pole plate is less than the maximum value of the second sub-pole plate in the length direction, the second sub-pole plate is triangular; the length direction is consistent with the movement direction of the mover; a straight line in the first direction passes through at least two second sub-pole plates, and the first direction is perpendicular to the movement direction of the mover.

[0012] Furthermore, any two adjacent second sub-plates form a centrally symmetrical pattern.

[0013] In addition, the arrangement period of the second sub-electrode in a single detection unit is two cycles.

[0014] In addition, the number of the second sub-electrodes in a single detection unit is at least three.

[0015] In addition, the capacitive displacement detection structure also includes a grounding element; the grounding element is disposed between the transmitting electrode plate and the receiving electrode plate. Attached Figure Description

[0016] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0017] Figure 1 This is a schematic diagram of a capacitive displacement detection structure according to the first embodiment of this solution;

[0018] Figure 2 This is a schematic diagram of another capacitive displacement detection structure according to the first embodiment of this solution;

[0019] Figure 3 This is a schematic diagram of a traditional capacitive displacement detection structure according to the first embodiment of this solution;

[0020] Figure 4 This is a schematic diagram of the capacitance detection result of a traditional capacitive displacement detection structure according to the first embodiment of this solution;

[0021] Figure 5 This is a schematic diagram of the distribution structure of the second sub-electrode of a capacitive displacement detection structure according to the first embodiment of this solution;

[0022] Figure 6 This is a schematic diagram of the capacitance detection result of a capacitive displacement detection structure according to the first embodiment of this solution;

[0023] Figure 7 This is a schematic diagram of the detection unit distribution structure of a capacitive displacement detection structure according to the second embodiment of this solution;

[0024] Figure 8 This is a schematic diagram of a capacitive displacement detection structure according to the second embodiment of this solution;

[0025] Figure 9 This is a schematic diagram of the capacitance detection result of a capacitive displacement detection structure according to the second embodiment of this solution;

[0026] Figure 10 This is a structural schematic diagram of a capacitive displacement detection structure according to the third embodiment of this solution;

[0027] Figure 11This is a schematic diagram of a capacitive displacement detection structure according to the fourth embodiment of this solution.

[0028] Figure label:

[0029] 1-Emitter plate; 1'-Conventional emitter plate;

[0030] 2' - Traditional receiving electrode; 21 - First sub-electrode; 22 - Second sub-electrode; 23 - Third sub-electrode;

[0031] 3'-Floating electrode plate; 3'-Traditional floating electrode plate;

[0032] 4-Detection unit;

[0033] 5-Grounding component. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the various embodiments of this application will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been presented in the various embodiments of this application to enable readers to better understand this application. However, the technical solutions claimed in this application can be implemented even without these technical details and various changes and modifications based on the following embodiments.

[0035] The division of the following embodiments is for ease of description and should not constitute any limitation on the specific implementation of this application. The various embodiments can be combined with and referenced by each other without contradiction.

[0036] The first embodiment of this application relates to a capacitive displacement detection structure, such as Figure 1 and Figure 2 As shown, it includes: a mover, a stator, a transmitting electrode 1, a receiving electrode 1, and a floating electrode 3; the transmitting electrode 1 and the receiving electrode 1 are both disposed on the stator, and the floating electrode 3 is disposed on the mover; the receiving electrode 1 includes: a first sub-electrode 21 and a second sub-electrode 22; the transmitting electrode 1, the first sub-electrode 21, and multiple second sub-electrodes 22 constitute a detection unit, the second sub-electrodes 22 in the detection unit are periodically arranged, and the second sub-electrodes 22 at the same position in different periods are connected to the same circuit channel, the first sub-electrode 21 is disposed opposite to all the second sub-electrodes 22 arranged in one period; the floating electrode 3 moves synchronously with the mover, and in any state during the movement of the floating electrode 3, the facing area of ​​the floating electrode 3 and the transmitting electrode 1 is always the same, and the floating electrode 3 has a facing area with at least two second sub-electrodes 22.

[0037] in Figure 1 This is a capacitive displacement detection structure with three second sub-plates forming one cycle. Figure 2This is a capacitive displacement detection structure with four second sub-electrodes per cycle. The floating electrode is made of conductive metal and is in a floating state, meaning it is not connected to the circuit. The width of the floating electrode in the direction of the arrangement of the transmitting and receiving electrodes is greater than the total width of the transmitting and receiving electrodes. In other words, the edge of the floating electrode in the width direction extends beyond the edge of the transmitting and receiving electrodes.

[0038] Traditional capacitive displacement detection structures, such as Figure 3 As shown, a conventional transmitting electrode 1' is positioned opposite four conventional receiving electrodes 2', and a conventional floating electrode 3' moves relative to the conventional transmitting electrode 1' and the four conventional receiving electrodes 2'. The conventional floating electrode 3' moves as shown in the diagram. Figure 3 When the device moves downwards as shown, the conventional transmitting electrode 1' and the four conventional receiving electrodes 2' form capacitors C1, C2, C3, and C4 respectively in the direction of movement. Assuming the length of each conventional receiving electrode 2' is L, and the travel range of the conventional floating electrode 3' is 0 to 2L, the detection results of capacitors C1, C2, C3, and C4 within the travel range of the conventional floating electrode 3' are as follows: Figure 4 As shown, within the stroke range of 0 to L, the detection results of capacitors C1 and C3 change as the traditional floating plate 3' moves. Therefore, the position of the traditional floating plate 3' can be determined based on the detection results of capacitors C1 and C3. Within the stroke range of L to 2L, the detection results of capacitors C2 and C4 change as the traditional floating plate 3' moves. Therefore, the position of the traditional floating plate 3' can be determined based on the detection results of capacitors C2 and C4, thus achieving displacement detection. In a traditional capacitive displacement detection structure, each traditional receiving plate 2' needs to be connected to a circuit channel. Therefore, in the traditional capacitive displacement detection structure with a stroke of 2L in the above example, four circuit channels need to be configured for the traditional receiving plate 2'.

[0039] With the same configuration of four circuit channels for the receiving plates, and each receiving plate having a length of L, the capacitive displacement detection structure using the scheme of this application is as follows: Figure 5 As shown, there is one first sub-electrode plate connected to one circuit channel. The second sub-electrode plates are arranged periodically, with a period of two. Within each period, there are three second sub-electrode plates. Second sub-electrode plates at the same position in different periods are connected to the same circuit channel. Figure 5 In the diagram, Rx1 in the first cycle and Rx1 in the second cycle are connected to the same circuit channel; Rx2 in the first cycle and Rx2 in the second cycle are connected to the same circuit channel; Rx3 in the first cycle and Rx3 in the second cycle are connected to the same circuit channel; emitter plate 1 and the two Rx1s form capacitor C1; emitter plate 1 and the two Rx2s form capacitor C2; emitter plate 1 and the two Rx3s form capacitor C3; and emitter plate 1 and the first sub-plate form capacitor C4. Figure 6 The diagram shows the detection results of each capacitor. C1 to C3 are used to determine the position of the floating electrode in each cycle, while C4 is used to determine which cycle the floating electrode is in, thus comprehensively determining the movement position of the floating electrode. For example, the changes in the detection results of C1 to C3 during the stroke 0 to L are exactly the same as those during the stroke 3L to 4L. Using only C1 to C3, these two stroke intervals cannot be distinguished, meaning the position of the floating electrode cannot be accurately determined. However, the detection results of capacitor C4 differ between the stroke 0 to L and the stroke 3L to 4L. The detection results of capacitor C4 can be used to determine the stroke interval of the floating electrode, and then the specific position within that stroke interval can be determined using the detection results of C1 to C3, thereby achieving accurate displacement detection. In this scheme, the length of each second sub-electrode is L, and the number of circuit channels configured for the receiving electrode is the same as that configured for the traditional receiving electrode in a traditional capacitive displacement detection structure—four in total. However, the stroke that this scheme can detect is 4L, which is greater than the 2L stroke that the traditional capacitive displacement detection structure can detect.

[0040] Compared to related technologies, in this embodiment of the application, in a structure where the mover displaces relative to the stator in a device, to detect the distance the mover moves, an emitting electrode plate and a receiving electrode plate are provided on the stator, and a floating electrode plate is provided on the mover. The arrangement of the receiving electrode plates is changed, dividing the receiving electrode plate into a first sub-electrode plate and a second sub-electrode plate. The emitting electrode plate, the first sub-electrode plate, and multiple second sub-electrode plates constitute a detection unit. The second sub-electrode plates in the detection unit are arranged periodically, and second sub-electrode plates at the same position in different periods are connected to the same circuit channel. The first sub-electrode plate is positioned opposite to all the second sub-electrode plates arranged in one period. The floating electrode plate moves synchronously with the mover, and in any state during the movement, the facing area of ​​the floating electrode plate and the emitting electrode plate is always the same. The floating plate and at least two second sub-plates have a directly opposite area. Based on the capacitance between the floating plate and the second sub-plates, the position of the floating plate and the position of the second sub-plates in each cycle can be determined. Based on the capacitance between the floating plate and the first sub-plate, the cycle in which the floating plate moves to the distribution of the second sub-plates can be determined. By combining the values ​​of both types of capacitance, the position of the floating plate can be accurately obtained. Since the floating plate moves synchronously with the mover, the movement distance of the mover can be determined based on the position of the floating plate. In the above structure, the second sub-plates at the same position in different cycles are connected to the same circuit channel, saving the number of circuit channels occupied by the receiving plate. With a limited number of circuit channels, accurate detection over a longer distance can be achieved.

[0041] The second embodiment of this application relates to a capacitive displacement detection structure, such as Figure 7As shown, compared to the first embodiment, in this embodiment, when there are multiple detection units 4, the receiving electrode plate further includes: a third sub-electrode plate 23; the third sub-electrode plate 23 is disposed opposite to at least one of the detection units 4, and the direction in which the third sub-electrode plate 23 is opposite to the detection unit 4 is the same as the direction in which the first sub-electrode plate is opposite to the second sub-electrode plate.

[0042] The detection principle of the capacitive displacement detection structure in this embodiment is as follows:

[0043] like Figure 8 As shown, taking an example where there are three second sub-electrodes 22 in each cycle, the second sub-electrodes 22 in each cycle are Rx1, Rx2, and Rx3 respectively. The emitter plate 1 forms a capacitor C1 with Rx1 in four cycles, a capacitor C2 with Rx2 in four cycles, a capacitor C3 with Rx3 in four cycles, a capacitor C4 with the first sub-electrode 1, and a capacitor C5 with the third sub-electrode 1. Figure 9 The results of each capacitor are shown. C1 to C4, as described in the first embodiment, can determine the position of the floating plate in a single detection unit 4. However, since the detection results of C1 to C4 are the same for strokes 0 to 4L and 6L to 10L, C1 to C4 alone cannot distinguish between these two stroke intervals, thus failing to accurately determine the position of the floating plate. However, the detection result of capacitor C5 differs between strokes 0 to 4L and 6L to 10L. The detection result of capacitor C5 can be used to determine the stroke interval in which the floating plate is located, and then the detection results of C1 to C4 can be used to determine the specific position within that stroke interval, thereby achieving accurate displacement detection. Compared to the first embodiment, this embodiment adds an extra circuit channel for connecting to the third sub-plate, but the detection stroke increases from 4L in the first embodiment example to 10L. With sufficient circuit channels, the detection stroke can be significantly increased by periodically increasing the number of second sub-plates and the number of sub-plates used to distinguish stroke intervals (periods).

[0044] The third embodiment of this application relates to a capacitive displacement detection structure. Compared to the previous embodiment, the shape of the second sub-electrode can be changed to achieve large-stroke detection when the length of the floating electrode is limited. When the length of the floating electrode is less than the maximum length of the second sub-electrode, the second sub-electrode is triangular; the length direction is consistent with the movement direction of the mover; a straight line in a first direction passes through at least two of the second sub-electrodes, the first direction being perpendicular to the movement direction of the mover and consistent with the width direction of the floating electrode. This ensures that the detection result of at least one capacitor changes when the floating electrode moves, avoiding detection blind spots.

[0045] For example, such as Figure 10As shown, the shape of the second sub-electrode is adjusted to a right triangle, and the hypotenuses of two adjacent second sub-electrodes are arranged opposite each other to form a rectangular pattern. Thus, when the length of the floating electrode 3 is less than the length of the right-angled side of the second sub-electrode 22 in the length direction, the detection result of the formed capacitance can change synchronously when the floating electrode 3 moves, so as to avoid the problem of inaccurate detection results caused by the relative area of ​​the floating electrode and the receiving electrode not changing.

[0046] In practical applications, the shape of the second sub-plate can be set as trapezoidal, triangular or irregular, as long as the capacitance detection result changes with the movement of the floating plate.

[0047] In addition, when the length of the floating electrode plate is greater than the length of the second sub-electrode plate, the shape of the second sub-electrode plate can also be set as a rectangle, triangle, trapezoid, etc.

[0048] The fourth embodiment of this application relates to a capacitive displacement detection structure, which, compared to the previous embodiments, such as Figure 11 As shown, the capacitive displacement detection structure in this embodiment further includes a grounding element 5; the grounding element 5 is disposed between the transmitting electrode plate and the receiving electrode plate. Specifically, if the transmitting electrode plate 1 is disposed between the first sub-electrode plate 21 and the second sub-electrode plate 22, the grounding element 5 is disposed between the transmitting electrode plate 1 and the first sub-electrode plate 21, and also between the transmitting electrode plate 1 and the second sub-electrode plate 22. In the second embodiment, if the capacitive displacement detection structure further includes a third sub-electrode plate, a grounding element can be disposed between the third sub-electrode plate and the transmitting electrode plate to achieve shielding of interference signals.

[0049] Applicable to all the above embodiments, the emitting electrode and the receiving electrode can be on the same plane, and the gap of the second sub-electrode in the length direction is as small as possible to avoid detection blind spots.

[0050] In addition, the shape of the second sub-plate can be set to be the same, all the second sub-plates are the same size, and any two adjacent second sub-plates form a centrally symmetrical figure. All of the above settings facilitate the subsequent calculation of the generated capacitance detection results.

[0051] Finally, if the number of second sub-plates in each cycle is greater than or equal to three, it is beneficial to use the centroid algorithm to process the capacitance detection results.

[0052] The travel range exemplified in the above embodiments refers to the travel range of the region where the second sub-electrode is located. Even if the travel of the floating electrode extends beyond a certain distance from the region where the second sub-electrode is located, its position can still be determined based on the capacitance detection results. For example, ... Figure 5In the structure shown, when the floating electrode plate moves within the travel range of 4L to 6L, the detection results of capacitors C1 to C3 are consistent with those of capacitors C1 to C3 within the travel range of L to 3L. The detection result of capacitor C4 remains at its minimum value within the travel range of 4L to 6L. Therefore, although the detection results of C1 to C3 within the travel range of 4L to 6L are consistent with those within the travel range of L to 3L, the detection result of capacitor C4 is different, thus accurately determining the travel range of the floating electrode plate. This achieves displacement detection of the floating electrode plate partially exceeding the area of ​​the second sub-electrode plate. When the floating electrode plate completely exceeds the area of ​​the second sub-electrode plate, the position of the floating electrode plate cannot be determined. The longest travel of the floating electrode plate satisfies the following formula: X = (2 a ×b)×L, where X represents the longest travel of the detected floating electrode, a represents the number of first sub-electrodes, b represents the number of second sub-electrodes, and L represents the length of each second sub-electrode.

[0053] This solution allows for an exponential expansion of the travel detection range while minimizing the number of circuit channels required.

[0054] Another feasible embodiment of this application relates to an electronic device, including the capacitive displacement detection structure as described above. It is particularly suitable for electronic devices requiring large stroke detection and with a limited number of circuit channels.

[0055] Compared with related technologies, the electronic device provided in this application embodiment is provided with the capacitive displacement detection structure provided in the aforementioned embodiment. Therefore, it also has the technical effects provided in the aforementioned embodiment, and will not be described in detail here.

[0056] Those skilled in the art will understand that the above embodiments are specific embodiments for implementing this application, and in practical applications, various changes can be made to them in form and detail without departing from the spirit and scope of this application.

Claims

1. A capacitive displacement detection structure, characterized in that, include: Moving element, stator, transmitting electrode, receiving electrode, and floating electrode; The transmitting electrode and the receiving electrode are both disposed on the stator, and the floating electrode is disposed on the moving element; The receiving electrode plate includes: a first sub-electrode plate and a second sub-electrode plate; The emitting electrode, the first sub-electrode, and a plurality of second sub-electrodes constitute a detection unit. The second sub-electrodes in the detection unit are arranged periodically, and the second sub-electrodes at the same position in different periods are connected to the same circuit channel. The first sub-electrode is arranged opposite to all the second sub-electrodes arranged in one period. The floating electrode plate moves synchronously with the moving element, and in any state during the movement of the floating electrode plate, the facing area of ​​the floating electrode plate and the emitting electrode plate is always the same, and the floating electrode plate has a facing area with at least two second sub-electrodes.

2. The capacitive displacement detection structure according to claim 1, characterized in that, When there are multiple detection units, the receiving electrode plate further includes: a third sub-electrode plate; The third sub-electrode is disposed opposite to at least one of the detection units, and the direction in which the third sub-electrode is opposite to the detection unit is the same as the direction in which the first sub-electrode is opposite to the second sub-electrode.

3. The capacitive displacement detection structure according to claim 1, characterized in that, The transmitting electrode and the receiving electrode are on the same plane.

4. The capacitive displacement detection structure according to claim 1, characterized in that, The second sub-electrode plates all have the same shape.

5. The capacitive displacement detection structure according to claim 4, characterized in that, When the length of the floating pole plate is less than the maximum value of the second sub-pole plate in the length direction, the second sub-pole plate is triangular; the length direction is consistent with the movement direction of the mover; A straight line in a first direction passes through at least two of the second sub-plates, the first direction being perpendicular to the direction of movement of the mover.

6. The capacitive displacement detection structure according to claim 4, characterized in that, Any two adjacent second sub-plates form a centrally symmetrical figure.

7. The capacitive displacement detection structure according to claim 1, characterized in that, The arrangement period of the second sub-electrode in a single detection unit is two cycles.

8. The capacitive displacement detection structure according to claim 1, characterized in that, The number of the second sub-electrodes in a single detection unit is at least three.

9. The capacitive displacement detection structure according to any one of claims 1 to 8, further comprising: Grounding components; The grounding element is disposed between the transmitting electrode and the receiving electrode.

10. An electronic device, characterized in that, include: The capacitive displacement detection structure as described in any one of claims 1 to 9.

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