Key detection system, device, method and storage medium

Abstract

The embodiment of the present application relates to the field of key technology, and discloses a key detection system, device, method and storage medium. The key detection system of the present application includes: a key, a driving circuit, a detection circuit, and a processing unit; the key includes a base and a moving component; the moving component penetrates the top surface of the base, and the moving component reciprocates vertically to the top surface; the moving component includes a mandrel and a conductor plate fixed relative to the mandrel; the base includes a main plate and a secondary plate fixed relative to the base, and the conductor plate is respectively arranged relative to the main plate and the secondary plate; the secondary plate, the conductor plate and the main plate form a target capacitor; when the mandrel reciprocates, the capacitance signal of the target capacitor changes; the driving circuit is connected to the secondary plate, and the detection circuit is connected to the main plate; the driving circuit drives the secondary plate to work, and the detection circuit detects the target capacitance; the processing unit is connected to the detection circuit, and determines the displacement of the key according to the target capacitance. Improve the accuracy of key displacement detection.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of key technology, and in particular to a key detection system, device, method and storage medium. Background Art

[0002] At present, electronic devices with keypads are widely used in production and life, such as keyboards, computers and other equipment. Taking keyboard keys as an example, conventional keyboard keys can only detect two states, on and off. When a conventional silicone keyboard is pressed, the circuit is turned on to realize the detection function, but it can only identify the two states of on and off, and cannot identify the intermediate process.

[0003] In order to detect the intermediate state of the key, a new type of keyboard that has emerged in the related technology based on the conventional keyboard is a magnetic axis keyboard. A small magnet is provided at the bottom of the key core shaft, and a Hall element is provided on the main circuit board of the keyboard. When the magnetic axis key is pressed, the distance between it and the Hall element changes, and the magnetic field strength detected by the Hall element changes. The key pressing displacement can be detected by detecting the magnetic field.

[0004] However, a HALL chip needs to be configured under each key of the magnetic axis keyboard, which is very expensive and consumes a lot of power. It is easily disturbed by external magnetic fields, temperature and other conditions, resulting in low accuracy in detecting key displacement. Summary of the invention

[0005] The purpose of the embodiments of the present application is to provide a key detection system, device, method and storage medium, so as to take into account both the detection accuracy and detection cost of the key displacement.

[0006] To solve the above technical problems, an embodiment of the present application provides a key detection system, including: a key, a drive circuit, a detection circuit, and a processing unit; the key includes a base and a moving component; the moving component passes through the top surface of the base, and the moving component reciprocates perpendicular to the top surface; the moving component includes a core shaft and a conductor plate fixed relative to the core shaft; the base includes a main pole plate and a secondary pole plate fixed relative to the base, and the conductor plate is respectively arranged relative to the main pole plate and the secondary pole plate; the secondary pole plate, the conductor plate and the main pole plate form a target capacitor; when the core shaft reciprocates, the capacitance signal of the target capacitor changes; the drive circuit is connected to the secondary pole plate, and the detection circuit is connected to the main pole plate; the drive circuit is used to drive the secondary pole plate to work, and the detection circuit is used to detect the target capacitance; the processing unit is connected to the detection circuit, and the processing unit is used to determine the displacement of the key according to the target capacitance.

[0007] An embodiment of the present application further provides an electronic device, comprising: the above-mentioned key detection system.

[0008] An embodiment of the present application further provides a key detection method, which is applied to the above-mentioned key detection system, and the method includes: detecting a capacitance signal generated by the target capacitance; and determining a pressing condition of the key according to a change in the capacitance signal.

[0009] An embodiment of the present application further provides a computer-readable storage medium storing a computer program, wherein the computer program implements the above-mentioned key detection method when executed by a processor.

[0010] In some embodiments, the number of the keys is multiple, and the multiple keys are arranged in an N*M matrix, where N and M are both integers greater than 0; the driving circuit includes N driving pins, and the detection circuit includes M detection pins; the secondary plates of the keys in each row are commonly connected to one of the driving pins of the driving circuit; and the main plates of the keys in each column are commonly connected to one of the detection pins of the detection circuit.

[0011] In some embodiments, the main pole plate includes a first pole plate and a second pole plate; the secondary pole plate, the conductor plate and the first pole plate form a first capacitor, and the secondary pole plate, the conductor plate and the second pole plate form a second capacitor; when the core shaft reciprocates, the capacitance signals of the first capacitor and the second capacitor change; the detection circuit is connected to the first pole plate and the second pole plate of the main pole plate; the detection circuit is used to detect the first capacitor and the second capacitor.

[0012] In some embodiments, the main pole plate includes two first pole plates, and the two first pole plates are symmetrically arranged on both sides of the second pole plate; there is a first gap between one first pole plate and the second pole plate, and there is a second gap between the other first pole plate and the second pole plate, and the extension direction of the first gap and the second gap is different from the reciprocating motion direction.

[0013] In some embodiments, two of the first pole plates and one of the second pole plates form a pole plate assembly, and the main pole plate includes a plurality of the pole plate assemblies; the plurality of the pole plate assemblies are arranged on the inner side wall of the base, and the plurality of the pole plate assemblies are arranged perpendicular to the reciprocating motion direction; in two adjacent pole plate assemblies, the first pole plate of one pole plate assembly is adjacent to the first pole plate of the other pole plate assembly and are arranged integrally.

[0014] In some embodiments, the number of the keys is multiple, and the multiple keys are arranged in an N*M matrix, where N and M are both integers greater than 0; the drive circuit includes N drive pins, and the detection circuit includes M first detection pins and M second detection pins; the secondary plates of the keys in each row are commonly connected to one drive pin of the drive circuit; the first plates of the main plates of the keys in each column are commonly connected to one first detection pin of the detection circuit, and the second plates of the main plates of the keys in each column are commonly connected to one second detection pin of the detection circuit.

[0015] In some embodiments, the number of the conductor plates is two, and the two conductor plates are respectively arranged on different outer side walls of the core shaft; the two conductor plates are connected by the wire; the secondary pole plate and the main pole plate are located on different inner side walls of the base, the secondary pole plate is arranged opposite to one of the conductor plates, and the main pole plate is arranged opposite to the other conductor plate.

[0016] The technical solution provided by the embodiments of the present application has at least the following advantages:

[0017] The key detection system of this embodiment includes a key, a driving circuit, a detection circuit, and a processing unit. A conductor plate, a secondary electrode plate, and a main electrode plate are arranged in the key structure. The conductor plate is arranged opposite to the secondary electrode plate and the main electrode plate, respectively. The conductor plate is relatively fixed to the core shaft, and the secondary electrode plate and the main electrode plate are relatively fixed to the base. The driving circuit is connected to the secondary electrode plate, and the detection circuit is connected to the main electrode plate. When the key is pressed or popped up, the core shaft drives the conductor plate to move downward or upward, and the relative area between the conductor plate and the secondary electrode plate and the relative area between the conductor plate and the main electrode plate change, thereby causing the capacitance signal of the target capacitance formed by the secondary electrode plate, the conductor plate and the main electrode plate to change. The processing unit can judge the moving distance of the key according to the target capacitance, determine the middle position of the key, and improve the accuracy of key displacement detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0019] Figure 1 is a schematic diagram of an exploded structure of a capacitive sensing button according to an embodiment of the present application;

[0020] Figure 2 is a structural schematic diagram of a capacitive induction button according to an embodiment of the present application;

[0021] Figure 3is a schematic diagram of an exploded structure of a capacitive sensing button according to an embodiment of the present application;

[0022] Figure 4 is a schematic structural diagram of a plurality of key arrangements according to an embodiment of the present application;

[0023] Figure 5 is a schematic diagram of an equivalent circuit of a key detection system according to an embodiment of the present application;

[0024] Figure 6 is a schematic structural diagram of a main pole plate according to an embodiment of the present application;

[0025] Figure 7 is a schematic structural diagram of a main pole plate according to an embodiment of the present application;

[0026] Figure 8 is a schematic structural diagram of a capacitor structure according to an embodiment of the present application when twisting occurs;

[0027] Fig. 9 is a schematic structural diagram of a main pole plate according to an embodiment of the present application;

[0028] Fig.10 is a schematic diagram of an equivalent circuit of a key detection system according to an embodiment of the present application;

[0029] Fig.11 According to an embodiment of the present application Figure 1 A schematic diagram of the structure of the corresponding capacitive induction button center axis seat;

[0030] Fig.12 According to an embodiment of the present application Figure 1 The structural diagram of the corresponding capacitive induction button center axis seat packaging SMT patch;

[0031] Fig.13 According to an embodiment of the present application Figure 3 A schematic diagram of the structure of the corresponding capacitive induction button center axis seat;

[0032] Fig.14 According to an embodiment of the present application Figure 3 The structural diagram of the corresponding capacitive induction button center axis seat packaging SMT patch;

[0033] Fig.15 This is a schematic diagram of the connection between the CHCT5562 chip and the host computer according to an embodiment of the present application;

[0034] Fig.16 It is a schematic diagram of the structure of the CHCT5562 chip according to an embodiment of the present application. DETAILED DESCRIPTION

[0035] In order to solve the problems of low detection accuracy of key displacement and high hardware cost of magnetic axis keys in related technologies, an embodiment of the present application relates to a key detection system, including: a key, a drive circuit, a detection circuit, and a processing unit; the key includes a base and a moving component; the moving component passes through the top surface of the base, and the moving component reciprocates perpendicular to the top surface; the moving component includes a core shaft and a conductor plate fixed relative to the position of the core shaft; the base includes a base, a main pole plate and a secondary pole plate fixed relative to the position of the base, and the conductor plate is respectively arranged relative to the main pole plate and the secondary pole plate; the secondary pole plate, the conductor plate and the main pole plate form a target capacitor; when the core shaft reciprocates, the capacitance signal of the target capacitor changes; the drive circuit is connected to the secondary pole plate, and the detection circuit is connected to the main pole plate; the drive circuit is used to drive the secondary pole plate to work, and the detection circuit is used to detect the target capacitance; the processing unit is connected to the detection circuit, and the processing unit is used to determine the displacement of the key according to the target capacitance.

[0036] The key detection system of this embodiment includes a key, a driving circuit, and a detection circuit. A conductor plate, a secondary electrode plate, and a main electrode plate are arranged in the key structure. The conductor plate is arranged opposite to the secondary electrode plate and the main electrode plate, respectively. The conductor plate is relatively fixed to the core shaft, and the secondary electrode plate and the main electrode plate are relatively fixed to the base. The driving circuit is connected to the secondary electrode plate, and the detection circuit is connected to the main electrode plate. When the key is pressed or popped up, the core shaft drives the conductor plate to move downward or upward, and the relative area between the conductor plate and the secondary electrode plate and the relative area between the conductor plate and the main electrode plate change, thereby causing the capacitance signal of the target capacitance formed by the secondary electrode plate, the conductor plate and the main electrode plate to change. The processing unit can judge the moving distance of the key according to the target capacitance, determine the middle position of the key, and improve the accuracy of key displacement detection.

[0037] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the embodiments of the present application will be described in detail below in conjunction with the accompanying drawings. However, it will be appreciated by those skilled in the art that in the present application, many technical details are proposed in order 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 scheme claimed in the present application can also be implemented. The division of the following embodiments is for the convenience of description, and the specific implementation of the present application should not be construed as any limitation, and the various embodiments can be combined and referenced with each other under the premise of no contradiction.

[0038] like Figure 1 FIG. 1 is a schematic diagram of the exploded structure of the capacitive induction button of this embodiment. Figure 2As shown, it is a structural schematic diagram of the capacitive sensing button of the present embodiment, the button of the button detection system of the present embodiment includes a base 1 and a moving component 2; the moving component passes through the top surface of the base 1, and the moving component 2 reciprocates perpendicular to the top surface; the moving component 2 includes a core shaft 21, and a conductor plate 22 relatively fixed to the core shaft 21; the base 1 includes a base 11, a main pole plate 12 and a secondary pole plate 13 relatively fixed to the base 11, and the conductor plate 22 is respectively arranged opposite to the main pole plate 12 and the secondary pole plate 13; the secondary pole plate 13, the conductor plate 22 and the main pole plate 12 form a target capacitor; when the core shaft 21 reciprocates, the capacitance signal of the target capacitor changes.

[0039] Specifically, the conductive pins at the lower ends of the main pole plate 12 and the secondary pole plate 13 pass through the base 11 and are inserted into the corresponding interfaces of the shaft seat 3. The conductive pins at the lower ends of the main pole plate 12 and the secondary pole plate 13 are respectively connected to the drive circuit and the detection circuit through the shaft seat 3, thereby forming a capacitive loop to facilitate the detection of the target capacitance, thereby realizing the detection of the button displacement. This solution is simple and reliable, low-cost, and can realize the hot-swap function. The motion component 2 of this embodiment also includes a cover plate 23, the cover plate 23 includes a hollow area, the cover plate 23 covers the core shaft 21, and the top surface of the core shaft 21 exposes the surface of the cover plate 23 through the hollow area. In one embodiment, Figure 1 As shown, there are two conductor plates 22, which are respectively arranged on different outer side walls of the core shaft 21; the two conductor plates 22 are connected by a wire (not shown); the secondary pole plate 13 and the main pole plate 12 are located on different inner side walls of the base 11, the secondary pole plate 13 is arranged opposite to one conductor plate 22, and the main pole plate 12 is arranged opposite to the other conductor plate 22. Specifically, the two conductor plates 22 are respectively arranged on two opposite outer side walls of the core shaft 21, and the main pole plate 12 and the secondary pole plate 13 are respectively arranged on different opposite inner side walls of the base 11.

[0040] In this embodiment, two conductor plates 22 connected by wires are arranged, the main pole plate 12 is arranged opposite to one conductor plate 22, and the secondary pole plate 13 is arranged opposite to the other conductor plate 22. The actual distance between the main pole plate 12 and the secondary pole plate 13 is changed by utilizing the jump bridging characteristics of the two conductor plates 22 for the capacitive signal, so that the design of the pole plates in the key can be more flexible and free from the space limitation of the pole plates. The main pole plate 12 and the secondary pole plate 13 can be arranged in the idle area of ​​the key, thereby improving the flexibility of the key setting, ensuring that the size of the key is small, and facilitating further reduction of the key size.

[0041] In another embodiment, the conductor plate 22 is located on the outer side wall of the core shaft 21, and the main pole plate 12 and the secondary pole plate 13 are located on the same inner side wall of the base 11. Figure 3, which is a schematic diagram of the exploded structure of the capacitive induction button of this embodiment, the conductor plate 22 is arranged on the outer wall of the core shaft 21, and the main pole plate 12 and the secondary pole plate 13 are located on the same inner wall of the base 11.

[0042] In this embodiment, the conductor plate 22 is arranged on the outer wall of the core shaft 21, and the main pole plate 12 and the secondary pole plate 13 are located on the same inner wall of the base 11 as the other conductor plate 22. The actual distance between the main pole plate 12 and the secondary pole plate 13 is changed by utilizing the characteristic of the conductor plate 22 for jumping bridge of the capacitive signal. This can make the design of the pole plate in the key more flexible and get rid of the space limitation of the pole plate. The main pole plate 12 and the secondary pole plate 13 can be arranged in the vacant area of ​​the key, thereby improving the flexibility of the key setting, ensuring that the size of the key is small, and facilitating further reduction of the key size.

[0043] In the key structure of this embodiment, the conductor plate 22, the main pole plate 12, and the secondary pole plate 13 are arranged opposite to the main pole plate 12 and the secondary pole plate 13 respectively, the conductor plate 22 is relatively fixed to the core shaft 21, and the main pole plate 12 and the secondary pole plate 13 are relatively fixed to the base 11; when the key is pressed or popped up, the core shaft 21 drives the conductor plate 22 to move downward or upward, and the relative area between the conductor plate 22 and the main pole plate 12, and the relative area between the conductor plate 22 and the secondary pole plate 13 change, so that the capacitance signal of the target capacitance changes, and the movement distance of the key can be judged according to the change of the target capacitance, and the middle position of the key can be determined, so as to realize the detection of the whole process during the key pressing process, and improve the accuracy of the key displacement detection. Compared with the magnetic axis solution, this embodiment has the advantages of good linearity, strong anti-interference ability, and low power consumption. Moreover, based on the ability to accurately determine the displacement of the core shaft 21, any trigger stroke can be set on the key, the trigger time can be adjusted, etc., to give the user a different tactile experience, and multi-level triggering can be designed on a single key to enrich the tactile experience of a single key.

[0044] The key detection system of this embodiment also includes a driving circuit, a detection circuit, and a processing unit. The driving circuit is connected to the secondary plate 13, and the detection circuit is connected to the main plate 12; the driving circuit is used to drive the secondary plate 13 to work, and the detection circuit is used to detect the target capacitance.

[0045] In one embodiment, the number of keys is multiple, and the multiple keys are arranged in an N*M matrix, where N and M are both integers greater than 0; the driving circuit includes N driving pins, and the detection circuit includes M detection pins; the secondary electrode 13 of each row of keys is commonly connected to a driving pin of the driving circuit; the main electrode 12 of each column of keys is commonly connected to a detection pin of the detection circuit.

[0046] like Figure 4As shown, it is a structural schematic diagram of the arrangement of multiple keys of this embodiment. The figure takes a computer keyboard as an example for illustration, and does not limit the protection scope of this embodiment. The number of keys contained in each row and each column can be set according to actual needs, and this embodiment does not make specific limitations.

[0047] like Figure 5 As shown, it is a schematic diagram of an equivalent circuit of the key detection system of the present embodiment. The key detection system of the present embodiment includes a driving circuit 10, a detection circuit 20, a processing unit (not shown in the figure) and a plurality of keys, and the plurality of keys are arranged in an N*M matrix. The driving circuit 10 includes N driving pins, namely Tx1, Tx2, Tx3, ..., TxN, and the detection circuit 20 includes M detection pins, namely Rx1, Rx2, Rx3, ..., RxM. In the figure, N is 3 and M is 4 for illustration, wherein vacant keys may be included to meet actual needs, but the vacant keys do not affect the implementation of the present embodiment, and the key detection needs can still be met.

[0048] Specifically, Figure 5 The dotted box in the figure represents a key, and the capacitor in the dotted box represents the target capacitance formed by the conductor plate 22, the main electrode plate 12, and the secondary electrode plate 13. The keys are arranged in the order of rows and columns. Among them, the secondary electrode plates 13 of the keys in each row are connected to a driving pin of the driving circuit 10, and the main electrode plates 12 of the keys in each column are connected to a detection pin of the detection circuit 20.

[0049] That is to say, the driving pin Tx1 of the driving circuit 10 is connected to the secondary pole plate 13 of button 1_1, button 1_2, button 1_3, and button 1_4, the driving pin Tx2 of the driving circuit 10 is connected to the secondary pole plate 13 of button 2_1 and button 2_2, and the driving pin Tx3 of the driving circuit 10 is connected to the secondary pole plate 13 of button 3_1, button 3_2, button 3_3, and button 3_4; the detection pin Rx1 of the detection circuit 20 is connected to the main pole plate 12 of button 1_1, button 2_1, and button 3_1, the detection pin Rx2 of the detection circuit 20 is connected to the main pole plate 12 of button 1_2, button 2_2, and button 3_2, the detection pin Rx3 of the detection circuit 20 is connected to the main pole plate 12 of button 1_3 and button 3_3, and the detection pin Rx4 of the detection circuit 20 is connected to the main pole plate 12 of button 1_4 and button 3_4.

[0050] Specifically, when the driving circuit 10 drives the secondary plate 13 to work through the driving pin, the secondary plate 13 can work simultaneously or in time-sharing. Taking time-sharing work as an example, the driving circuit 10 sends a driving signal in time-sharing. When the driving circuit 10 sends a driving signal through the driving pin Tx1, the secondary plates 13 of the keys 1_1, 1_2, 1_3, and 1_4 in the first row start to work, and the detection pins Rx1, Rx2, Rx3, and Rx4 of the detection circuit 20 receive the capacitance signals of the target capacitances of the keys 1_1, 1_2, 1_3, and 1_4, respectively. If the key 1_1 is pressed at this time, the capacitance signal of the target capacitance received by the detection pin Rx1 of the detection circuit 20 changes. According to the change, it can be determined that the key 1_1 is pressed and the displacement of the key 1_1 is pressed. The situation where the user presses the keys 1_2, 1_3, and 1_4 is similar, and will not be repeated here. In this way, the pressing state of all the keys in the first row is obtained, thereby determining the corresponding instructions of the user. After that, the driving pin Tx1 of the driving circuit 10 stops sending signals, and the driving circuit 10 sends a driving signal through the driving pin Tx2. The detection pins Rx1 and Rx2 of the detection circuit 20 receive the target capacitance of the key 2_1 and the key 2_2, and the pressing state of the key 2_1 and the key 2_2 can be further obtained through the capacitance value of the target capacitance; the rest can be deduced by analogy until the entire scanning process is completed. In the arrangement of the entire circuit, vacancies are allowed to exist, which does not affect the detection effect.

[0051] Specifically, each detection circuit 20 includes a plurality of detection units, wherein each detection pin is connected to a detection unit, and each detection unit is used to obtain a target capacitance, thereby realizing the detection of a capacitance signal.

[0052] Specifically, the processing unit of this embodiment is connected to the detection circuit 20, and the detection circuit 20 sends the acquired target capacitance to the processing unit. After acquiring the target capacitance, the processing unit calculates the capacitance according to the capacitance calculation formula C=εS / 4πkd, where ε is the dielectric constant of the medium, k is the electrostatic force constant, S is the facing area between the conductor plate 22 and the main pole plate 12, and d is the distance between the conductor plate 22 and the main pole plate 12. The facing area S between the conductor plate 22 and the main pole plate 12 can be calculated, and the displacement of the key being pressed can be obtained based on the facing area S.

[0053] Specifically, the corresponding relationship between the target capacitance and the key displacement amount can be pre-stored inside the processing unit. After the processing unit obtains the target capacitance, the key displacement amount can be directly obtained according to the target capacitance, thereby improving the efficiency of obtaining the key displacement amount.

[0054] This embodiment uses this circuit connection method to set the arrangement of the entire circuit to correspond to the arrangement of the key structure. The secondary electrode 13 of each row of keys shares a driving pin, and the main electrode 12 of each column of keys shares a detection pin. This not only simplifies the complexity of the entire circuit, but also eliminates the need to set a separate driving pin and a detection pin for each key, thereby saving the cost of the entire circuit.

[0055] In one embodiment, the main plate 12 of the key of this embodiment includes a first plate and a second plate; Figure 6 As shown, it is a schematic diagram of the structure of the main pole plate 12 of this embodiment, the main pole plate 12 includes a first pole plate 121 and a second pole plate 122, wherein the secondary pole plate 13, the conductor plate 22 and the first pole plate 121 form a first capacitor, and the secondary pole plate 13, the conductor plate 22 and the second pole plate 122 form a second capacitor; when the core shaft 21 reciprocates, the capacitance signals of the first capacitor and the second capacitor change; the detection circuit 20 is connected to the first pole plate 121 and the second pole plate 122 of the main pole plate 12; the detection circuit 20 is used to detect the first capacitor and the second capacitor.

[0056] Since the relationship (C1-C2) / (C1+C2) can be obtained after calculation (C1-C2) / (C1+C2)=(S1-S2) / (S1+S2), wherein C1 is the first capacitor, C2 is the second capacitor, S1 is the area directly opposite to the first electrode 121 and the conductor plate 22, and S2 is the area directly opposite to the second electrode 122 and the conductor plate 22, the relationship (C1-C2) / (C1+C2) can eliminate the influence of the electrode distance on the capacitance. Therefore, after the detection circuit 20 of this embodiment sends the first capacitor C1 and the second capacitor C2 to the processing unit, the processing unit calculates the value of (S1-S2) / (S1+S2) according to the first capacitor C1 and the second capacitor C2, and the key displacement that meets the value can be determined based on the value.

[0057] Specifically, the processing unit can pre-store the corresponding relationship between the value of (S1-S2) / (S1+S2) and the key displacement amount. After the processing unit obtains the first capacitor C1 and the second capacitor C2, the value of the relationship (C1-C2) / (C1+C2) can be directly calculated according to the first capacitor C1 and the second capacitor C2. The value of (S1-S2) / (S1+S2) can be obtained without complicated calculations. Then, the key displacement amount can be directly obtained according to the corresponding relationship between the value of (S1-S2) / (S1+S2) and the key displacement amount.

[0058] Specifically, the main pole plate 12 includes a first pole plate 121 and a second pole plate 122. The first pole plate 121 and the second pole plate 122 are triangular structures. The first pole plate 121 and the second pole plate 122 can be spliced ​​together into a rectangle. The conductor plate 22 is respectively arranged opposite to the first pole plate 121 and the second pole plate 122; the capacitance between the conductor plate 22 and the first pole plate 121 is C1, and the capacitance between the conductor plate 22 and the second pole plate 122 is C2; taking the movement of the conductor plate 22 from bottom to top as an example, C1 linearly decreases and C2 linearly increases, and the influence of the uncertainty of the spacing between the conductor plate 22 and the main pole plate 12 can be eliminated by the relationship (C1-C2) / (C1+C2).

[0059] In this embodiment, the main electrode plate 12 is divided into a first electrode plate 121 and a second electrode plate 122 to form a capacitor between the conductor plate 22 and the first electrode plate 121, and a capacitor between the conductor plate 22 and the second electrode plate 122. By performing corresponding relationship operations on the two capacitors, the displacement of the conductor plate 22, i.e., the key, can be accurately obtained, thereby improving the accuracy of key detection.

[0060] However, during the operation of the key, if the conductor plate 22 is twisted relative to the first electrode plate 121 and the second electrode plate 122, the twisting will cause the equivalent distance between the conductor plate 22 and the first electrode plate 121 to increase, and the equivalent distance between the conductor plate 22 and the second electrode plate 122 to decrease. The relationship (C1-C2) / (C1+C2) cannot offset the influence of the distance between the electrodes. Still using this relationship will cause serious errors in the determined displacement of the conductor plate 22, i.e., the key, affecting the accuracy of key position detection.

[0061] Therefore, in order to solve the problem of poor key displacement detection accuracy caused by torsion, in one embodiment, the present application further sets the number of first pole plates 121 in the main pole plate 12 to two, such as Figure 7 As shown, it is a schematic diagram of the structure of the main pole plate 12 of this embodiment, the main pole plate 12 includes two first pole plates 121 and one second pole plate 122; the two first pole plates 121 are symmetrically arranged on both sides of the second pole plate 122; there is a first gap between one first pole plate 121 and the second pole plate 122, and there is a second gap between the other first pole plate 121 and the second pole plate 122, and the extension direction of the first gap and the second gap is different from the reciprocating motion direction.

[0062] The key of this embodiment is provided with the above-mentioned structure. When the conductor plate 22 is twisted when the key is pressed or popped out, the influence of the twisting of the conductor plate 22 on the capacitance generated by the two first plates 121 can offset each other, thereby reducing the change in the first capacitance. The influence of the twisting of the conductor plate 22 on the capacitance generated by the second plate 122 can also offset each other, thereby reducing the change in the second capacitance, thereby offsetting the capacitance deviation caused by the twisting of the conductor plate 22, improving the accuracy of capacitance detection, and further improving the accuracy of key position detection.

[0063] Specifically, the conductor plate 22, the main electrode plate 12, and the secondary electrode plate 13 in the key of this embodiment form a capacitor structure. In the figure, the conductor plate 22 reciprocates up and down, and the conductor plate 22 is provided with a fixed stroke amount, and the conductor plate 22 reciprocates within the fixed stroke amount along the reciprocating direction. Among them, the conductor plate 22 is located on the outer side wall of the core shaft 21, and the main electrode plate 12 and the secondary electrode plate 13 are located on the inner side wall of the base 11.

[0064] Specifically, the main pole plate 12 includes two first pole plates 121 and a second pole plate 122; the first pole plate 121 and the second pole plate 122 are arranged on the same plane perpendicular to the reciprocating motion direction, and the two first pole plates 121 are symmetrically arranged on both sides of the second pole plate 122; the secondary pole plate 13 is arranged opposite to the main pole plate 12.

[0065] Among them, in order to change the capacitance signals of the first capacitor and the second capacitor when the core shaft 21 reciprocates, the length of the first electrode 121 in the reciprocating direction and the length of the second electrode 122 in the reciprocating direction are both greater than the stroke of the conductor plate 22 in the reciprocating direction; thereby ensuring that when the core shaft 21 reciprocates, the relative area between the conductor plate 22 and the first electrode 121, the second electrode 122 changes, and the relative area between the conductor plate 22 and the secondary electrode 13 changes, thereby changing the capacitance signals of the first capacitor and the second capacitor. According to the changes in the first capacitor and the second capacitor, the moving distance of the key can be judged, the middle position of the key can be determined, and the accuracy of the key displacement detection is improved.

[0066] Specifically, a first gap L1 exists between one first electrode plate 121 and the second electrode plate 122 , and a second gap L2 exists between the other first electrode plate 121 and the second electrode plate 122 . The extending directions of the first gap L1 and the second gap L2 are different from the reciprocating motion direction.

[0067] Specifically, in this embodiment, the two first pole plates 121 are of the same size and shape, and are symmetrically arranged on both sides of the second pole plate 122, and symmetrically arranged along the central axis of the second pole plate 122. Therefore, the first gap L1 between one first pole plate 121 and the second pole plate 122 and the second gap L2 between the other first pole plate 121 and the second pole plate 122 are also the same in shape and size, and the first gap L1 and the second gap L2 are symmetrically arranged along the central axis of the second pole plate 122, and the direction of the central axis of the second pole plate 122 is the same as the reciprocating motion direction of the core shaft 21.

[0068] Specifically, the extension directions of the first gap L1 and the second gap L2 are different from the reciprocating direction of the core shaft 21, that is, there is an angle between the first gap L1 and the reciprocating direction of the core shaft 21, and there is also a symmetrical angle between the second gap L2 and the reciprocating direction of the core shaft 21; when the conductor plate 22 follows the reciprocating motion of the core shaft 21, the first capacitor and the second capacitor both change, and the displacement of the conductor plate 22 can be determined based on the changes in the first capacitor and the second capacitor, thereby determining the displacement of the key.

[0069] like Figure 8 As shown, it is a schematic diagram of the structure when the capacitor structure of this embodiment is twisted, and the dotted line is the central axis of the second electrode plate 122, and the conductor plate 22 rotates with the dotted line as the axis. When the conductor plate 22 is twisted during the movement of the mandrel 21, the distance between point A and the first electrode plate 121 is large, and the distance between point D and the other first electrode plate 121 is small. The relationship between points A, B, C, and D in the conductor plate 22 and the main electrode plate 12 is large-medium-large-medium-small-small. For points A and D, their opposite positions are both the first electrode plate 121, so the effects of the twisting cancel each other out. Similarly, the effects of the twisting at points B and C also cancel each other out, and it can be approximately considered that the equivalent distances of the two first electrodes 121 from the conductor plate 22 and the equivalent distances of the second electrode plate 122 from the conductor plate 22 are equal to the equivalent distances of point O on the central axis from the conductor plate 22, thereby compensating for the effects of the twisting, improving the accuracy of the capacitance detection, and further improving the accuracy of the key displacement detection.

[0070] Specifically, the two first pole plates 121 and the second pole plate 122 together form a rectangular parallelepiped; the length of the first gap L1 and the second gap L2 in the reciprocating direction of the core shaft 21 is equal to the length of the pole plate assembly in the reciprocating direction of the core shaft 21; the length of the first gap L1 and the second gap L2 in the target direction is equal to half the width of the pole plate assembly in the target direction; the target direction is a direction perpendicular to the reciprocating direction of the core shaft 21 and parallel to the surface of the main pole plate 12 close to the conductor plate.

[0071] In one embodiment, in a plate assembly, the extension direction of the first gap L1 and the second gap L2 is a straight line, such as Figure 7As shown, from bottom to top, the distance between the first gap L1 and the second gap L2 increases linearly, and the first gap L1 and the second gap L2 are V-shaped. Specifically, the first gap L1 extends from the midpoint of the bottom of the cuboid to the left vertex of the cuboid, and the second gap L2 extends from the midpoint of the bottom of the cuboid to the right vertex of the cuboid. In this embodiment, by setting the extension direction of the first gap L1 and the second gap L2 to a straight line, when the conductor plate 22 moves in the reciprocating direction with the core shaft 21, the area of ​​the conductor plate 22 facing the first electrode plate 121 and the second electrode plate 122 changes linearly, and the change of the relationship (C1-C2) / (C1+C2) is only related to the change of the facing area. The relationship (C1-C2) / (C1+C2) can not only offset the influence of the distance between the electrodes, but also change linearly with the change of the facing area, thereby further improving the accuracy of capacitance detection and the accuracy of key position detection.

[0072] In other embodiments, the extension direction of the first gap L1 and the second gap L2 can be a curve, and the reciprocating motion direction is from bottom to top. The distance between the first gap L1 and the second gap L2 only needs to gradually increase. For example, the first gap L1 and the second gap L2 are U-shaped.

[0073] Specifically, in the case of a smaller twist, that is, when the twist distance of the conductor plate 22 is much smaller than the distance between the electrodes, the relationship (C1-C2) / (C1+C2) is close to the case where no twist occurs, and the influence of the twist of the conductor plate 22 on the relationship (C1-C2) / (C1+C2) can be ignored; therefore, in this embodiment, through the above-mentioned key structure, when the conductor plate 22 is twisted a small distance, the relationship (C1-C2) / (C1+C2) can still offset the influence of the distance between the electrodes, thereby improving the accuracy of capacitance detection, and further improving the accuracy of key position detection.

[0074] However, when the torsion distance of the conductor plate 22 is large, the accuracy of the method of using only two first pole plates 121 and one second pole plate 122 will also be reduced, and there will be some situations where it cannot be fully compensated. Therefore, in order to solve the problem of low key detection accuracy caused by large torsion and further improve the accuracy of key displacement detection, an embodiment of the present application further forms a pole plate assembly with two first pole plates 121 and one second pole plate 122, and the main pole plate 12 includes multiple pole plate assemblies.

[0075] like Fig. 9As shown, it is a structural schematic diagram of the main pole plate 12 of this embodiment, the main pole plate 12 includes a plurality of pole plate assemblies, the plurality of pole plate assemblies are arranged on the inner side wall of the base, and the plurality of pole plate assemblies are arranged perpendicular to the reciprocating motion direction; in two adjacent pole plate assemblies, the first pole plate 121 of one pole plate assembly is adjacent to the first pole plate 121 of the other pole plate assembly and is arranged integrally.

[0076] In this embodiment, by setting a structure of multiple plate assemblies in the main plate 12, when the space inside the key is determined, as many plate assemblies as possible can be set, and the space occupied by each plate assembly in the arrangement direction is as small as possible. In the case of twisting of the conductor plate 22, the twisting between the conductor plate 22 and each plate assembly will be greatly reduced relative to the overall twisting, thereby further eliminating the capacitance deviation caused by the twisting of the conductor plate 22 and each plate assembly, thereby improving the accuracy of the overall capacitance detection and the accuracy of the position detection. It is worth mentioning that the more the number of plate assemblies, the closer the conductor plate 22 and each plate assembly are to a parallel state, the better the effect of eliminating the capacitance deviation caused by the twisting, and the higher the accuracy of the key displacement detection.

[0077] Specifically, the first electrode plates 121 and the second electrode plates 122 are arranged alternately to offset the effect of the twisting of the mandrel 21. The extension direction of the first gap L1 and the second gap L2 is a straight line. When there are multiple electrode assemblies, the multiple first gaps L1 and the multiple second gaps L2 are W-shaped. The W-shaped main pole plate 12 can further improve the compensation effect. In this embodiment, the extension direction of the first gap L1 and the second gap L2 is set to a straight line, and the W-shaped main pole plate 12 is set, so that when the conductor plate 22 moves along the reciprocating direction, the facing area of ​​the conductor plate 22 and the first pole plate 121, and the facing area of ​​the conductor plate 22 and the second pole plate 122 tend to change linearly, and the setting of multiple plate assemblies offsets the influence of torsion on capacitance. The change of the relationship (C1-C2) / (C1+C2) is as much as possible related to the change of the facing area, so that the relationship (C1-C2) / (C1+C2) tends to change linearly with the change of the facing area, thereby further improving the accuracy of capacitance detection and further improving the accuracy of key displacement detection.

[0078] It can be seen that Figure 6 , Figure 7 , Fig. 9In the structures of the three main pole plates 12 shown, the main pole plate 12 is divided into two types of pole plates, namely a first pole plate 121 and a second pole plate 122. The first pole plate 121 of each column of keys is connected to a first detection pin of the detection circuit 20, and the second pole plate 122 of each column of keys is connected to a second detection pin of the detection circuit 20. Therefore, when the detection circuit 20 detects a key, it can obtain two capacitors, namely a first capacitor and a second capacitor, so as to determine the pressing condition of the key through the first capacitor and the second capacitor, thereby improving the accuracy of key detection.

[0079] like Fig.10 As shown, it is a schematic diagram of an equivalent circuit of the key detection system of the present embodiment. The key detection system of the present embodiment includes a driving circuit 10, a detection circuit 20 and a plurality of keys, and the plurality of keys are arranged in an N*M matrix, where N and M are both integers greater than 0; the driving circuit 10 includes N driving pins, namely Tx1, Tx2, Tx3, ..., TxN, the detection circuit 20 includes M first detection pins and M second detection pins, the first detection pins include Rx11, Rx21, Rx31, ..., RxM1, and the second detection pins include Rx12, Rx22, Rx32, ..., RxM2. Fig.10 In the example, N is 3 and M is 2, respectively. To meet actual needs, vacant keys may be included. However, the vacant keys do not affect the implementation of this embodiment and can still meet the needs of key detection.

[0080] Specifically, Fig.10 The dotted box in the figure represents a key, the capacitor C1 in the dotted box represents a first capacitor formed by the conductor plate 22, the secondary plate 13, and the first plate 121 of the main plate 12, and the capacitor C2 in the wire frame represents a second capacitor formed by the conductor plate 22, the secondary plate 13, and the second plate 122 of the main plate 12, and the keys are arranged in the order of rows and columns. The secondary plates 13 of the keys in each row are connected to a driving pin of the driving circuit 10, the first plate 121 of the main plate 12 of the keys in each column are connected to a first detection pin of the detection circuit 20, and the second plate 122 of the main plate 12 of the keys in each column are connected to a second detection pin of the detection circuit 20.

[0081] That is to say, the driving pin Tx1 of the driving circuit 10 is connected to the secondary pole plate 13 of the button 1_1 and the button 1_2, the driving pin Tx2 of the driving circuit 10 is connected to the secondary pole plate 13 of the button 2_1, and the driving pin Tx3 of the driving circuit 10 is connected to the secondary pole plate 13 of the button 3_1 and the button 3_2; the first detection pin Rx11 of the detection circuit 20 is connected to the first pole plate 121 of the main pole plate 12 of the button 1_1, the button 2_1, and the button 3_1, the second detection pin Rx12 of the detection circuit 20 is connected to the second pole plate 122 of the main pole plate 12 of the button 1_1, the button 2_1, and the button 3_1, the first detection pin Rx21 of the detection circuit 20 is connected to the first pole plate 121 of the main pole plate 12 of the button 1_2 and the button 3_2, and the second detection pin Rx22 of the detection circuit 20 is connected to the second pole plate 122 of the main pole plate 12 of the button 1_2 and the button 3_2.

[0082] Specifically, each detection circuit 20 includes a plurality of detection units, each of which is connected to a first detection pin or a second detection pin, and each detection unit is used to obtain a first capacitor or a second capacitor, thereby realizing the detection of a capacitance signal. Among them, the first detection pin and the second detection pin are arranged alternately, and the first plate 121 and the second plate 122 of the main plate 12 of the same key are connected to the adjacent first detection pin and the second detection pin, that is, the adjacent first detection pin and the second detection pin of the detection circuit 20 can obtain the first capacitance and the second capacitance of the same key, which is convenient for obtaining the capacitance signal and calculating the displacement of the key.

[0083] Specifically, when the driving circuit 10 drives the secondary plate 13 to work through the driving pin, the secondary plate 13 can work simultaneously or in time division, that is, the detection circuit 20 receives the signal in real time, and the driving circuit 10 can scan in time division or simultaneously.

[0084] Taking time-sharing operation as an example, the driving circuit 10 sends a driving signal in a time-sharing manner. When the driving circuit 10 sends a driving signal through the driving pin Tx1, the secondary plates 13 of the keys 1_1 and 1_2 in the first row start to work, and the keys in other rows do not work. The first detection pins Rx11 and Rx21 of the detection circuit 20 receive the capacitance signals of the first capacitors of the keys 1_1 and 1_2 respectively, and the second detection pins Rx12 and Rx22 of the detection circuit 20 receive the capacitance signals of the second capacitors of the keys 1_1 and 1_2 respectively. If the key 1_1 is pressed at this time, the capacitance signal of the first capacitor received by the first detection pin Rx11 of the detection circuit 20 changes, and the capacitance signal of the second capacitor received by the second detection pin Rx12 of the detection circuit 20 changes. According to the changes of the first capacitance and the second capacitance, it can be determined that the key 1_1 is pressed and the displacement of the key 1_1 is pressed. The situation in which the user presses the key 1_2 is similar and will not be repeated here. In this way, the pressing state of all keys in the first row is obtained, thereby determining the corresponding indication of the user. Afterwards, the driving pin Tx1 of the driving circuit 10 stops sending signals, and the driving circuit 10 sends driving signals through the driving pin Tx2, and so on, until the entire scanning process is completed. In the arrangement of the entire circuit, vacancies are allowed to exist without affecting the detection effect.

[0085] Specifically, this embodiment obtains capacitance information through the above-mentioned circuit structure, calculates and processes the capacitance data, and obtains the current real-time displacement of the key. At a certain moment, after the displacement exceeds a certain threshold, a specific action can be triggered according to the setting. For example, a key may have two levels of triggering cases: when typing, for the A key, when the displacement is 0, there is no action; when the displacement is between 0.5mm and 2mm, type lowercase a; when it exceeds 2mm, type uppercase A. Furthermore, there can be application scenarios with more levels of triggering, for example: the A key is designed as the accelerator key in a game. The deeper the press, the deeper the accelerator is pressed, and pressing it to the bottom is equivalent to pressing the accelerator to the bottom; since the capacitance key detection of this embodiment has high linearity and high resolution, it can well simulate the process of stepping on the accelerator and improve the user experience.

[0086] Specifically, all the keys in the full keyboard can only partially use the above-mentioned capacitive keys. For example, some special keys in the keyboard use the above-mentioned capacitive keys, and other positions can be replaced with ordinary keys, and only corresponding processing is required in the circuit and software. Among them, for each capacitive key, the trigger threshold, function, etc. can be set independently to improve the flexibility of the key.

[0087] Specifically, for high-performance capacitance detection chips, such as the CHCT5562 chip, a complete scanning cycle can be achieved within 10ms, so the reporting rate of each capacitance button can reach more than 100Hz; if the reporting rate needs to be further improved, simultaneous scanning can also be used.

[0088] This embodiment uses this circuit connection method to set the arrangement of the entire circuit corresponding to the arrangement of the key structure. The secondary plates 13 of each row of keys share a driving pin, the first plates 121 of the main plates 12 of each column of keys share a first detection pin, and the second plates 122 of the main plates 12 of each column of keys share a second detection pin, which not only simplifies the complexity of the circuit, but also saves the cost of the circuit. At the same time, this embodiment determines the displacement of the key through the first capacitor and the second capacitor, thereby improving the accuracy of the key displacement detection.

[0089] Specifically, the capacitive sensing button of the present embodiment also includes a shaft seat 3, the main pole plate 12 includes a first pin pin1, a second pin pin2, and a ground pin GND, the secondary pole plate 13 includes a third pin pin3, the first pin pin1, the second pin pin2, the third pin pin3, and the ground pin GND pass through the bottom of the base 11 and are connected to the corresponding interface on the shaft seat 3; the motion component 2 of the present embodiment also includes a cover plate 23, the cover plate 23 includes a hollow area, the cover plate 23 covers the core shaft 21, and the top surface of the core shaft 21 exposes the surface of the cover plate 23 through the hollow area.

[0090] Specifically, the shaft seat 3 includes a first interface, a second interface, and a third interface. Fig.11 As shown, in this embodiment Figure 1 The corresponding structural diagram of the capacitive induction button center axis seat 3 is as follows: Fig.12 As shown, in this embodiment Figure 1 The corresponding structural diagram of the capacitive induction button center axis seat 3 packaging SMT patch is as follows Fig.13 As shown, in this embodiment Figure 3 The corresponding structural diagram of the capacitive induction button center axis seat 3 is as follows: Fig.14 As shown, in this embodiment Figure 3 The corresponding structural diagram of the capacitive sensing button center axis seat 3 packaging SMT patch.

[0091] Specifically, the shaft seat 3 includes a first interface a, a second interface b, and a third interface c. The secondary pole plate 13 and the first pole plate 121 and the second pole plate 122 in the main pole plate 12 are fixed to the base 11 by glue or snaps, and the pin positions at the bottom of the secondary pole plate 13, the first pole plate 121, and the second pole plate 122 extend out of the base 11 to facilitate subsequent connection with the shaft seat 3; wherein, multiple first pole plates 121 share a first pin pin1, multiple second pole plates 122 share a second pin pin2, and the secondary pole plate 13 has a third pin pin3.

[0092] like Figure 1 , Figure 3 It can be seen from the two capacitive sensing buttons shown that the main pole plate 12 includes a first pin pin1 and a second pin pin2, the secondary pole plate 13 includes a third pin pin3, the first interface a is connected to the first pin pin1, and the first pin pin1 is connected to each first pole plate 121 in the main pole plate 12; the second interface b is connected to the second pin pin2, and the second pin pin2 is connected to each second pole plate 122 in the main pole plate 12; the third interface c is connected to the third pin pin3.

[0093] Specifically, the back side of the main pole plate 12 is paved with the ground, that is, the side of the main pole plate 12 away from the conductor plate 22 is paved with the ground, which plays a role in shielding interference signals. Therefore, the main pole plate 12 also includes a ground pin GND, and the corresponding shaft seat 3 also includes a ground port GND1. The ground pin GND of the main pole plate 12 is connected to the ground port GND1 on the shaft seat 3. The shaft seat 3 is provided with a plurality of surface mount technology (SMT, Surface Mount Technology) patches, which are respectively connected to the first interface a, the second interface b, the third interface b, and the ground port GND1, wherein the patch SMT1 is connected to the first interface a, the patch SMT2 is connected to the second interface b, the patch SMT3 is connected to the third interface c, and the patch SMT4 is connected to the ground port GND1.

[0094] Specifically, the positions of the multiple interfaces on the shaft seat 3 are set corresponding to the pin positions of the main pole plate 12 and the auxiliary pole plate 13. The multiple interfaces on the shaft seat 3, such as, Figure 1 and Fig.11 , Fig.12 The corresponding interface of shaft seat 3 and SMT patch correspondence, Figure 3 and Fig.13 , Fig.14 The corresponding interface of the shaft seat 3 and the SMT patch can be set according to the pin positions of the main pole plate 12 and the secondary pole plate 13 in practice, so that the pins of the main pole plate 12 and the secondary pole plate 13 pass through the base 11 and are directly connected to the corresponding interface on the shaft seat 3, thereby reducing the pin length as much as possible and reducing the size of the button.

[0095] Specifically, the shaft seat 3 is fixed to the main circuit board through the SMT technology. After the conductive pins at the lower ends of the main pole plate 12 and the secondary pole plate 13 are inserted into the shaft seat 3, they are connected to the main circuit board to form a capacitor loop through the contact between the pins, so as to detect the changes of the first capacitor and the second capacitor, thereby realizing the detection of the key displacement. This solution is simple and reliable, low cost, and can realize the hot plug function.

[0096] Specifically, the conductor plate 22 is generally a conductive metal, which is fixed on the core shaft 21 to form a complete structure and moves up and down following the pressing of the core shaft 21; the secondary plate 13 can be manufactured by metal stamping; the main plate 12 can be manufactured using a PCB board, or it can be manufactured using an FPC or a metal sheet.

[0097] Specifically, the driving circuit 10 and the detection circuit 20 of the key detection system of this embodiment can be provided by a chip, such as Fig.15 As shown, it is a connection diagram between the chip and the host computer. The chip 201 and the host computer 202 are connected through an interface, and the interface type can be GPIO (General Purpose Input Output), I2C (Inter Integrated Circuit), I3C (Improved Inter Integrated Circuit) or SPI (Serial Peripheral interface).

[0098] Specifically, the chip 201 may be a CHCT5562 chip, which provides a driving pin and a detection pin of a driving circuit, and the CHCT5562 chip is connected to a host computer 202, and is controlled and calculated by the host computer 202. The host computer 202 may be a main control chip of a keyboard, and the CHCT5562 chip transmits the pressing status of all current keys to the host computer 202 for subsequent processing by the host computer 202, including determining the pressed key and the pressing displacement of the key according to the capacitance.

[0099] Specifically, since the CHCT5562 chip itself has a microprocessor (MCU, Micro Controller Unit) and multiple communication interfaces, it can be used as a host computer to control other chips. It can also be used as a main control chip + capacitor detection chip, saving costs. Fig.16 , which is a schematic diagram of the structure of the CHCT5562 chip, includes a microcontroller 50 , a communication interface 60 , and a capacitive digital signal processing module 70 .

[0100] Specifically, the CHCT5562 chip has 20 drive pins and 42 detection pins, and is a high-performance capacitance detection chip. Therefore, only one CHCT5562 chip is needed to realize full keyboard key detection. Moreover, according to the detection principle, the status of all keys can be measured, processed, and displayed in real time, so full-key anti-ghosting can be achieved naturally without additional processing.

[0101] Take the CHCT5562 chip as the main control chip + capacitor detection chip, and additionally control the light emitting diode (LED) as an example for explanation. The emitter plate 30 sends a specific voltage and current signal, and the signal is controlled by the capacitor digital signal processing module 70. After the receiving plate 40 receives the electrical signal, it is processed by the capacitor digital signal processing module 70 and sent to the microcontroller 50 to determine which keys are pressed at this moment. Assuming that the "A" key is pressed at this time, the information is transmitted to the host computer such as a computer host through the communication interface 60, and the host computer takes corresponding actions, such as typing the letter "A"; at the same time, the "A" key is pressed, and the information is processed by the microcontroller 50 and transmitted to the LED light control chip through the communication interface 60. After the LED light chip receives the signal, it controls the LED light of the A key to light up. It should be noted that the emitter plate 30 is the secondary plate 13 in the above embodiment, and the receiving plate 40 is the first plate 121 or the second plate 122 of the main plate 12 in the above embodiment.

[0102] On the other hand, an embodiment of the present application further provides an electronic device, including: the above-mentioned key detection system.

[0103] Compared with the related art, the electronic device provided by this embodiment of the present invention is provided with the key detection system provided by the aforementioned embodiment. Therefore, it also has the technical effects provided by the aforementioned embodiment, which will not be elaborated here.

[0104] The division of various components above is only for clear description. When implemented, 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 protection scope of this embodiment.

[0105] Another embodiment of the present invention relates to a key detection method, which is applied to the above-mentioned key detection system, and the method includes: detecting a capacitance signal generated by a target capacitor; and determining a key pressing condition according to a change in the capacitance signal.

[0106] Specifically, the pressing condition includes whether the keyboard is pressed and the displacement of the key. The moving distance of the key is determined according to the change of the capacitance signal. The specific description is given in the above embodiment and will not be repeated here.

[0107] The step division of the various methods above is only for clear description. When implemented, they can be combined into one step or some steps can be split and decomposed into multiple steps. As long as they include the same logical relationship, they are all within the protection scope of the present invention. Adding insignificant modifications or introducing insignificant designs to the algorithm or process without changing the core design of the algorithm and process are all within the protection scope of the invention.

[0108] Another embodiment of the present invention relates to a computer-readable storage medium storing a computer program, which implements the above method embodiment when executed by a processor.

[0109] That is, those skilled in the art can understand that all or part of the steps in the above-mentioned embodiment method can be completed by instructing the relevant hardware through a program, and the program is stored in a storage medium, including several instructions to enable a device (which can be a single-chip microcomputer, chip, etc.) or a processor to execute all or part of the steps of each embodiment method of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0110] Those skilled in the art will appreciate that the above embodiments are specific embodiments for implementing the present application, and 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 key detection system, characterized in that: include: Buttons, drive circuits, detection circuits, and processing units; The key comprises a base and a moving assembly; the moving assembly penetrates the top surface of the base, and the moving assembly reciprocates perpendicular to the top surface; the moving assembly comprises a core shaft and a conductor plate fixed relative to the core shaft; The base comprises a base, a main pole plate and a secondary pole plate fixed relative to the base, and the conductor plate is respectively arranged relative to the main pole plate and the secondary pole plate; The secondary plate, the conductor plate and the main plate form a target capacitor; when the core shaft reciprocates, the capacitance signal of the target capacitor changes; The driving circuit is connected to the secondary plate, and the detection circuit is connected to the main plate; The driving circuit is used to drive the secondary plate to work, and the detection circuit is used to detect the target capacitance; The processing unit is connected to the detection circuit, and the processing unit is used to determine the displacement of the key according to the target capacitance; The number of the conductor plates is two, and the two conductor plates are respectively arranged on different outer side walls of the core shaft; The two conductor plates are connected by a wire; The secondary pole plate and the main pole plate are located on different inner side walls of the base. The secondary pole plate is arranged opposite to one of the conductor plates, and the main pole plate is arranged opposite to the other conductor plate.

2. The key detection system according to claim 1, characterized in that: The number of the buttons is multiple, and the multiple buttons are arranged in an N*M matrix, where N and M are both integers greater than 0; the driving circuit includes N driving pins, and the detection circuit includes M detection pins; The secondary plates of the buttons in each row are commonly connected to one of the driving pins of the driving circuit; The main pole plates of each column of the buttons are commonly connected to one of the detection pins of the detection circuit.

3. The key detection system according to claim 1, characterized in that: The main plate includes a first plate and a second plate; the secondary plate, the conductor plate and the first plate form a first capacitor, and the secondary plate, the conductor plate and the second plate form a second capacitor; When the mandrel reciprocates, the capacitance signals of the first capacitor and the second capacitor change; The detection circuit is connected to the first pole plate and the second pole plate of the main pole plate; the detection circuit is used to detect the first capacitor and the second capacitor.

4. The key detection system according to claim 3, characterized in that: The main electrode plate includes two first electrode plates, which are symmetrically arranged on both sides of the second electrode plate; there is a first gap between one of the first electrode plates and the second electrode plate, and there is a second gap between the other first electrode plate and the second electrode plate, and the extension direction of the first gap and the second gap is different from the reciprocating motion direction.

5. The key detection system according to claim 4, characterized in that: Two of the first pole plates and one of the second pole plates form a pole plate assembly, and the main pole plate includes a plurality of the pole plate assemblies; the plurality of the pole plate assemblies are arranged on the inner side wall of the base, and the plurality of the pole plate assemblies are arranged perpendicular to the reciprocating motion direction; in two adjacent pole plate assemblies, the first pole plate of one pole plate assembly is adjacent to the first pole plate of the other pole plate assembly and is arranged integrally.

6. The key detection system according to any one of claims 3 to 5, characterized in that: The number of the buttons is multiple, and the multiple buttons are arranged in an N*M matrix, where N and M are both integers greater than 0; the driving circuit includes N driving pins, and the detection circuit includes M first detection pins and M second detection pins; The secondary plates of the buttons in each row are commonly connected to one of the driving pins of the driving circuit; The first electrode plate of the main electrode plate of each column of the buttons is commonly connected to a first detection pin of the detection circuit, and the second electrode plate of the main electrode plate of each column of the buttons is commonly connected to a second detection pin of the detection circuit.

7. An electronic device, characterized in that: include: A key detection system as claimed in any one of claims 1 to 6.

8. A key detection method, characterized in that: Applied to the key detection system according to any one of claims 1 to 6, the method comprises: detecting a capacitance signal generated by the target capacitance; The pressing condition of the key is determined according to the change of the capacitance signal.

9. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the key detection method according to claim 8 is implemented.

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