Key detection system, device, method, and storage medium

Abstract

The present application relates to the technical field of keys, and discloses a key detection system, a device, a method, and a storage medium. The key detection system in the present application comprises keys, a drive circuit (10), and a detection circuit (20); each key comprises a base (1) and a moving assembly (2); the moving assembly (2) passes through the top surface of the base (1), and the moving assembly (2) moves back and forth perpendicularly to the top surface; the moving assembly (2) comprises a core shaft (21) and conductor plates (22) fixed relative to the core shaft (21); the base (1) comprises a bottom seat (11), and a primary electrode plate (12) and a secondary electrode plate (13) which are fixed relative to the bottom seat (11); the conductor plates (22) are respectively arranged opposite to the primary electrode plate (12) and the secondary electrode plate (13); the drive circuit (10) is connected to the secondary electrode plate (13), and the detection circuit (20) is connected to the primary electrode plate (12); the drive circuit (10) drives the secondary electrode plate (13) to work. Thus, the accuracy of key displacement detection is improved.

Description

Key detection system, device, method and storage medium Cross-reference to related applications

[0001] The present application is based on the Chinese patent application No. 2024112302538, filed on September 3, 2024, and claims priority to the above-mentioned Chinese patent application, the whole content of which is incorporated herein by reference. TECHNICAL FIELD

[0002] The present application relates to the technical field of keys, in particular to a key detection system, device, method and storage medium. BACKGROUND

[0003] At present, electronic devices of key type are widely used in production and life, such as keyboards, computers and other devices. Taking keyboard keys as an example, conventional keyboard keys can only detect two states of on and off. The conventional silica gel keyboard makes the circuit conductive after pressing the key, thereby realizing the detection function, but only two states of on and off can be recognized, and the intermediate process cannot be recognized.

[0004] In order to detect the intermediate state of the key, a new type of keyboard appears in the related technology on the basis of the conventional keyboard, which is a magnetic shaft keyboard. The bottom of the key shaft is provided with a small magnet, and the main circuit board of the keyboard is provided with a HALL element. The distance between the magnetic shaft key and the HALL element changes after the magnetic shaft key is pressed, and the magnetic field strength detected by the HALL element changes. The detection of the magnetic field can realize the detection of the displacement of the key pressing.

[0005] However, a HALL chip needs to be configured under each key of the magnetic shaft keyboard, which has high cost and large power consumption, and is easily disturbed by external magnetic field, temperature and other conditions, resulting in low detection accuracy of the key displacement. SUMMARY

[0006] The purpose of the embodiments of the present application is to provide a key detection system, device, method and storage medium, so as to balance the detection accuracy and detection cost of the key displacement.

[0007] To solve the above technical problems, the embodiment of the present application provides a key detection system, comprising: a key, a driving circuit, a detection circuit, a processing unit; the key comprises a base and a moving component; the moving component penetrates through the top surface of the base, and the moving component reciprocates vertically to the top surface; the moving component comprises a mandrel, and a conductor plate fixed opposite to the position of the mandrel; the base comprises a bottom, a main electrode plate and a secondary electrode plate fixed opposite to the position of the bottom, and the conductor plate is arranged opposite to the main electrode plate and the secondary electrode plate respectively; the secondary electrode plate, the conductor plate and the main electrode plate form a target capacitor; in the case of reciprocating movement of the mandrel, the capacitance signal of the target capacitor changes; the driving circuit is connected to the secondary electrode plate, and the detection circuit is connected to the main electrode plate; the driving circuit is used for driving the secondary electrode plate to work, and the detection circuit is used for detecting the target capacitor; the processing unit is connected to the detection circuit, and the processing unit is used for determining the displacement of the key according to the target capacitor.

[0008] The embodiment of the present application further provides an electronic device, comprising the key detection system.

[0009] The embodiment of the present application further provides a key detection method applied to the key detection system, and the method comprises: detecting the capacitance signal generated by the target capacitor; and determining the pressing condition of the key according to the change of the capacitance signal.

[0010] The embodiment of the present application further provides a computer readable storage medium, which stores a computer program, and the computer program is executed by a processor to implement the key detection method.

[0011] In some embodiments, the number of keys is multiple, and the multiple keys are arranged in an N*M matrix, wherein N and M are both integers greater than 0; the driving circuit comprises N driving pins, and the detection circuit comprises M detection pins; the secondary electrode plates of each row of keys are commonly connected to one driving pin of the driving circuit; and the main electrode plates of each column of keys are commonly connected to one detection pin of the detection circuit.

[0012] In some embodiments, the main electrode plate comprises a first electrode plate and a second electrode plate; the secondary electrode plate, the conductor plate and the first electrode plate form a first capacitor, and the secondary electrode plate, the conductor plate and the second electrode plate form a second capacitor; in the case of reciprocating movement of the mandrel, the capacitance signals of the first capacitor and the second capacitor change; the detection circuit is connected to the first electrode plate and the second electrode plate of the main electrode plate; and the detection circuit is used for detecting the first capacitor and the second capacitor.

[0013] In some embodiments, the main electrode plate comprises two first electrode plates, which are symmetrically arranged on two sides of the second electrode plate; one of the first electrode plates is separated from the second electrode plate by a first gap, and the other first electrode plate is separated from the second electrode plate by a second gap, the extension directions of the first gap and the second gap being different from the reciprocating direction.

[0014] In some embodiments, two first electrode plates and one second electrode plate form an electrode plate assembly, and the main electrode plate comprises a plurality of electrode plate assemblies; the plurality of electrode plate assemblies are arranged on the inner side wall of the base, and the plurality of electrode plate assemblies are arranged along a direction perpendicular to the reciprocating direction; in two adjacent electrode plate assemblies, the first electrode plate of one electrode plate assembly is adjacent to and integrally arranged with the first electrode plate of the other electrode plate assembly.

[0015] In some embodiments, the number of keys is a plurality, and the plurality of keys are arranged in an N*M matrix, N and M being integers greater than 0; the driving circuit comprises N driving pins, and the detection circuit comprises M first detection pins and M second detection pins; the auxiliary electrode plates of each row of keys are commonly connected to one driving pin of the driving circuit; the first electrode plates of the main electrode plates of each column of keys are commonly connected to one first detection pin of the detection circuit, and the second electrode plates of the main electrode plates of each column of keys are commonly connected to one second detection pin of the detection circuit.

[0016] In some embodiments, the number of conductor plates is two, and the two conductor plates are arranged on different outer side walls of the mandrel, respectively; the two conductor plates are connected by the wire; the auxiliary electrode plate and the main electrode plate are located on different inner side walls of the base, the auxiliary electrode plate is arranged opposite to one conductor plate, and the main electrode plate is arranged opposite to the other conductor plate.

[0017] The technical scheme provided by the embodiments has at least the following advantages:

[0018] The key detection system of the embodiment comprises a key, a driving circuit, a detection circuit, and a processing unit, a conductor plate, an auxiliary electrode plate, and a main electrode plate are arranged in the key structure, the conductor plate is arranged opposite to the auxiliary electrode plate and the main electrode plate, respectively, the conductor plate is fixed opposite to the mandrel, the auxiliary electrode plate and the main electrode plate are fixed opposite to the base, the driving circuit is connected to the auxiliary electrode plate, and the detection circuit is connected to the main electrode plate; when the key is pressed or popped up, the mandrel drives the conductor plate to move downward or upward, the relative areas of the conductor plate and the auxiliary electrode plate and the relative areas of the conductor plate and the main electrode plate change, so that the capacitance signal of the auxiliary electrode plate, the conductor plate, and the main electrode plate forming a target capacitor changes, the processing unit can determine the movement distance of the key and determine the intermediate position of the key according to the target capacitor, and the accuracy of the key displacement detection is improved. Attached Figure Description

[0019] 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.

[0020] Figure 1 is an exploded view of a capacitive touch button according to an embodiment of this application;

[0021] Figure 2 is a schematic diagram of the structure of a capacitively sensitive key according to an embodiment of the present application;

[0022] Figure 3 is an exploded view of a capacitive touch button according to an embodiment of this application;

[0023] Figure 4 is a schematic diagram of the arrangement of multiple buttons according to an embodiment of this application;

[0024] Figure 5 is an equivalent circuit diagram of a key detection system according to an embodiment of the present application;

[0025] Figure 6 is a schematic diagram of the structure of a main electrode plate according to an embodiment of this application;

[0026] Figure 7 is a schematic diagram of the structure of a main electrode plate according to an embodiment of this application;

[0027] Figure 8 is a schematic diagram of the capacitor structure according to an embodiment of the present application when it is twisted;

[0028] Figure 9 is a schematic diagram of the structure of a main electrode plate according to an embodiment of this application;

[0029] Figure 10 is an equivalent circuit diagram of a key detection system according to an embodiment of the present application;

[0030] Figure 11 is a structural schematic diagram of the capacitive sensing key shaft seat corresponding to Figure 1 in an embodiment of this application;

[0031] Figure 12 is a schematic diagram of the structure of the SMT surface mount of the capacitive sensing key shaft corresponding to Figure 1 in one embodiment of this application;

[0032] Figure 13 is a structural schematic diagram of the capacitive sensing key shaft seat corresponding to Figure 3 in one embodiment of this application;

[0033] Figure 14 is a schematic diagram of the structure of the SMT surface mount of the capacitive sensing key shaft corresponding to Figure 3 in one embodiment of this application.

[0034] Figure 15 is a schematic diagram of the connection between the CHCT5562 chip and the host computer according to an embodiment of this application;

[0035] FIG. 16 is a structural schematic diagram of CHCT5562 chip according to an embodiment of the present application. DETAILED DESCRIPTION

[0036] In order to solve the problems of low detection accuracy and high hardware cost of the key displacement of the magnetic shaft key in the related art, an embodiment of the present application relates to a key detection system, which comprises a key, a driving circuit, a detection circuit, and a processing unit. The key comprises a base and a moving component. The moving component penetrates the top surface of the base and reciprocally moves vertically to the top surface. The moving component comprises a core shaft and a conductor plate fixed relative to the position of the core shaft. The base comprises a base, a main pole plate and a secondary pole plate fixed relative to the position of the base. The conductor plate is arranged opposite to the main pole plate and the secondary pole plate respectively. The secondary pole plate, the conductor plate and the main pole plate form a target capacitor. The capacitance signal of the target capacitor changes under the reciprocating movement of the core shaft. The driving circuit is connected to the secondary pole plate, and the detection circuit is connected to the main pole plate. The driving circuit is used to drive the secondary pole plate to work, and the detection circuit is used to detect the target capacitor. The processing unit is connected to the detection circuit, and is used to determine the displacement of the key according to the target capacitor.

[0037] The key detection system of the embodiment comprises a key, a driving circuit and a detection circuit. The conductor plate, the secondary pole plate and the main pole plate are arranged in the structure of the key. The conductor plate is arranged opposite to the secondary pole plate and the main pole plate respectively. The conductor plate is fixed relative to the core shaft, and the secondary pole plate and the main pole plate are fixed relative to the base. The driving circuit is connected to the secondary pole plate, and the detection circuit is connected to the main pole plate. When the key is pressed or popped up, the core shaft drives the conductor plate to move downward or upward. The relative area of the conductor plate and the secondary pole plate and the relative area of the conductor plate and the main pole plate change, so that the capacitance signal of the target capacitor formed by the secondary pole plate, the conductor plate and the main pole plate changes. The processing unit can determine the moving distance of the key according to the target capacitor, determine the intermediate position of the key, and improve the detection accuracy of the key displacement.

[0038] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the embodiments of the present application will be described in detail below with reference to the drawings. However, those skilled in the art can understand that in the embodiments of the present application, many technical details are proposed in order to make the readers better understand the present application. However, the technical solutions claimed by the present application can be implemented even without these technical details and various changes and modifications based on the following embodiments. The division of the following embodiments is for the convenience of description, and should not constitute any limitation on the specific implementation of the present application. The embodiments can be combined and referenced with each other without contradiction.

[0039] As shown in Figure 1, it is an exploded structural schematic diagram of the capacitive sensing key of the embodiment, as shown in Figure 2, it is a structural schematic diagram of the capacitive sensing key of the embodiment, the key of the key detection system of the embodiment includes a base 1 and a moving assembly 2; the moving assembly penetrates through the top surface of the base 1, and the moving assembly 2 reciprocates vertically to the top surface; the moving assembly 2 includes a mandrel 21, and a conductor plate 22 fixed opposite to the position of the mandrel 21; the base 1 includes a base 11, a main pole plate 12 and a secondary pole plate 13 fixed opposite to the position of the base 11, and the conductor plate 22 is arranged opposite to the main pole plate 12 and the secondary pole plate 13 respectively; the secondary pole plate 13, the conductor plate 22 and the main pole plate 12 form a target capacitor; in the case of reciprocating movement of the mandrel 21, the capacitance signal of the target capacitor changes.

[0040] Specifically, the conductive pins at the lower end of the main pole plate 12 and the secondary pole plate 13 are inserted into the corresponding interfaces of the shaft seat 3 after penetrating through the base 11, and the conductive pins at the lower end of the main pole plate 12 and the secondary pole plate 13 are connected to the driving circuit and the detection circuit respectively through the shaft seat 3, so as to form a capacitor loop, so as to detect the target capacitor, thereby realizing the detection of the displacement of the key. This scheme is simple and reliable, low in cost, and can realize hot plug function. The moving assembly 2 of the embodiment further includes a cover plate 23, the cover plate 23 includes a hollow area, the cover plate 23 covers the mandrel 21, and the top surface of the mandrel 21 is exposed to the surface of the cover plate 23 through the hollow area. In one embodiment, as shown in Figure 1, the number of conductor plates 22 is two, and the two conductor plates 22 are arranged on different outer side walls of the mandrel 21 respectively; the two conductor plates 22 are connected by wires (not marked in the figure); 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 arranged on the two opposite outer side walls of the mandrel 21 respectively, and the main pole plate 12 and the secondary pole plate 13 are arranged on the opposite different inner side walls of the base 11 respectively.

[0041] The embodiment changes the actual distance between the main pole plate 12 and the secondary pole plate 13 by using the jumping bridging characteristics of the two conductor plates 22 to the capacitance signal, so that the design of the pole plate in the key can be more flexible, and the space limitation of the pole plate can be broken, the main pole plate 12 and the secondary pole plate 13 can be arranged in the idle area of the key, the flexibility of the key arrangement is improved, the size of the key is ensured to be small, and the further reduction of the size of the key is facilitated.

[0042] In another embodiment, the conductor plate 22 is arranged on the outer side wall of the mandrel 21, and the main electrode plate 12 and the auxiliary electrode plate 13 are arranged on the same inner side wall of the base 11. As shown in FIG. 3, which is an exploded structural schematic diagram of the capacitive inductive key of the embodiment, the conductor plate 22 is arranged on the outer side wall of the mandrel 21, and the main electrode plate 12 and the auxiliary electrode plate 13 are arranged on the same inner side wall of the base 11.

[0043] In the embodiment, the actual distance between the main electrode plate 12 and the auxiliary electrode plate 13 is changed by arranging the conductor plate 22 on the outer side wall of the mandrel 21 and arranging the main electrode plate 12 and the auxiliary electrode plate 13 on the same inner side wall of the base 11, and using the jump bridging characteristics of the conductor plate 22 to the capacitive signal. The design of the electrode plate in the key can be more flexible, and the space limitation of the electrode plate can be broken. The main electrode plate 12 and the auxiliary electrode plate 13 can be arranged in the idle area of the key, the flexibility of the key arrangement is improved, the size of the key is ensured to be small, and the further reduction of the size of the key is facilitated.

[0044] In the key structure of the embodiment, the conductor plate 22, the main electrode plate 12, and the auxiliary electrode plate 13 are arranged oppositely with the main electrode plate 12 and the auxiliary electrode plate 13, the conductor plate 22 is fixed oppositely with the mandrel 21, and the main electrode plate 12 and the auxiliary electrode plate 13 are fixed oppositely with the base 11. When the key is pressed or lifted, the mandrel 21 drives the conductor plate 22 to move downward or upward, the relative area of the conductor plate 22 and the main electrode plate 12 and the relative area of the conductor plate 22 and the auxiliary electrode plate 13 change, so that the capacitive signal of the target capacitor changes. The movement distance of the key can be determined according to the change of the target capacitor, the intermediate position of the key is determined, the detection of the whole process of the key pressing process is realized, the accuracy of the key displacement detection is improved, and compared with the magnetic shaft scheme, the embodiment has the advantages of good linearity, strong anti-interference ability, and low power consumption. On the basis of accurately determining the displacement of the mandrel 21, any trigger stroke can be arranged on the key, the trigger time can be adjusted, different haptic experiences can be brought to the user, and multiple levels of triggering can be designed on a single key to enrich the haptic experience of a single key.

[0045] The key detection system of the embodiment further includes a driving circuit, a detection circuit, and a processing unit. The driving circuit is connected to the auxiliary electrode plate 13, and the detection circuit is connected to the main electrode plate 12. The driving circuit is used to drive the auxiliary electrode plate 13 to work, and the detection circuit is used to detect the target capacitor.

[0046] In one embodiment, the number of keys is multiple, and the multiple keys are arranged in an N*M matrix. 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 auxiliary electrode plates 13 of each row of keys are commonly connected to one driving pin of the driving circuit. The main electrode plates 12 of each column of keys are commonly connected to one detection pin of the detection circuit.

[0047] As shown in FIG. 4, it is a structure diagram of the arrangement of the plurality of keys of the embodiment, and the keyboard is taken as an example of the computer keyboard for illustration, which does not limit the protection scope of the embodiment. Each row and each column contains a number of keys, which can be set according to actual needs, and the embodiment is not specifically limited.

[0048] As shown in FIG. 5, it is an equivalent circuit diagram of the key detection system of the embodiment. The key detection system of the embodiment includes a driving circuit 10, a detection circuit 20, a processing unit (not marked in the figure), and a plurality of keys. The plurality of keys are arranged in an N*M matrix. The driving circuit 10 includes N driving pins, i.e., Tx1, Tx2, Tx3, …, TxN. The detection circuit 20 includes M detection pins, i.e., Rx1, Rx2, Rx3, …, RxM. In the figure, N is taken as 3 and M is taken as 4 for illustration, wherein, in order to meet the actual needs, there can be a vacancy key, but the vacancy key does not affect the implementation of the embodiment, and the key detection needs can still be met.

[0049] Specifically, the dashed box in FIG. 5 represents a key, and the capacitor in the dashed box represents the target capacitor formed by the conductor plate 22, the main electrode plate 12, and the auxiliary electrode plate 13. The keys are arranged according to the row and column order. The auxiliary electrode plate 13 of each row of keys is commonly connected to one driving pin of the driving circuit 10, and the main electrode plate 12 of each column of keys is commonly connected to one detection pin of the detection circuit 20.

[0050] That is, the driving pin Tx1 of the driving circuit 10 is connected to the auxiliary electrode plates 13 of the keys 1_1, 1_2, 1_3, and 1_4. The driving pin Tx2 of the driving circuit 10 is connected to the auxiliary electrode plates 13 of the keys 2_1 and 2_2. The driving pin Tx3 of the driving circuit 10 is connected to the auxiliary electrode plates 13 of the keys 3_1, 3_2, 3_3, and 3_4. The detection pin Rx1 of the detection circuit 20 is connected to the main electrode plates 12 of the keys 1_1, 2_1, and 3_1. The detection pin Rx2 of the detection circuit 20 is connected to the main electrode plates 12 of the keys 1_2, 2_2, and 3_2. The detection pin Rx3 of the detection circuit 20 is connected to the main electrode plates 12 of the keys 1_3 and 3_3. The detection pin Rx4 of the detection circuit 20 is connected to the main electrode plates 12 of the keys 1_4 and 3_4.

[0051] Specifically, when the driving circuit 10 drives the sub-plate 13 through the driving pin, the sub-plate 13 can work at the same time or in time-sharing. Taking the time-sharing as an example, the driving circuit 10 sends the driving signal in time-sharing, when the driving circuit 10 sends the driving signal through the driving pin Tx1, the sub-plate 13 of the first row of keys 1_1, 1_2, 1_3, 1_4 starts to work, and the detection pin Rx1, Rx2, Rx3, Rx4 of the detection circuit 20 respectively receives the capacitance signal of the target capacitor of the key 1_1, 1_2, 1_3, 1_4. If the key 1_1 is pressed at this time, the capacitance signal of the target capacitor received by the detection pin Rx1 of the detection circuit 20 changes, and 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 user presses the keys 1_2, 1_3, 1_4, and the like, which will not be described here. Through this way, the pressing state of all keys in the first row is obtained, so as to determine the corresponding indication of the user. Then, the driving pin Tx1 of the driving circuit 10 stops sending the signal, and the driving circuit 10 sends the driving signal through the driving pin Tx2. The detection pin Rx1, Rx2 of the detection circuit 20 receives the target capacitor of the key 2_1, 2_2, and the pressing state of the key 2_1, 2_2 can be further obtained through the capacitance value of the target capacitor; the rest can be deduced, until the whole scanning process is completed. In the arrangement of the whole circuit, there is a vacancy, which does not affect the detection effect.

[0052] Specifically, each detection circuit 20 includes a plurality of detection units, each detection pin is connected to a detection unit, and each detection unit is used to obtain a target capacitor, so as to realize the detection of the capacitance signal.

[0053] Specifically, the processing unit of the embodiment is connected to the detection circuit 20, and the detection circuit 20 sends the obtained target capacitor to the processing unit. After obtaining the target capacitor, the processing unit can calculate the facing area S between the conductor plate 22 and the main plate 12 according to the capacitance calculation formula C = εS / 4πkd, wherein ε is the dielectric constant of the medium, k is the electrostatic force constant, S is the facing area of the conductor plate 22 and the main plate 12, and d is the distance between the conductor plate 22 and the main plate 12. According to the facing area S, the displacement of the key being pressed can be obtained.

[0054] Specifically, the processing unit can pre-store the corresponding relationship between the target capacitor and the key displacement. After the processing unit obtains the target capacitor, the key displacement can be directly obtained according to the target capacitor, so as to improve the efficiency of obtaining the key displacement.

[0055] The embodiment corresponds the arrangement mode of the whole circuit to the arrangement mode of the button structure through the circuit connection mode, the sub-plate 13 of each row of buttons shares one driving pin, and the main plate 12 of each column of buttons shares one detection pin, which not only simplifies the complexity of the whole circuit, but also saves the cost of the whole circuit without setting one driving pin and one detection pin for each button.

[0056] In one embodiment, the main plate 12 of the button of the embodiment includes a first plate and a second plate. As shown in FIG. 6, which is a structural schematic diagram of the main plate 12 of the embodiment, the main plate 12 includes a first plate 121 and a second plate 122, wherein the sub-plate 13, the conductor plate 22 and the first plate 121 form a first capacitor, and the sub-plate 13, the conductor plate 22 and the second plate 122 form a second capacitor; in the case of reciprocating movement of the shaft 21, the capacitance signals of the first capacitor and the second capacitor change; the detection circuit 20 is connected to the first plate 121 and the second plate 122 of the main plate 12; and the detection circuit 20 is used for detecting the first capacitor and the second capacitor.

[0057] Since the relationship (C1-C2) / (C1+C2) can be calculated as (C1-C2) / (C1+C2)=(S1-S2) / (S1+S2) after calculation, wherein C1 is the first capacitor, C2 is the second capacitor, S1 is the facing area of the first plate 121 and the conductor plate 22, and S2 is the facing area of the second plate 122 and the conductor plate 22, the relationship (C1-C2) / (C1+C2) can eliminate the influence of the plate distance on the capacitor, therefore, after the detection circuit 20 of the 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 amount satisfying the value can be determined according to the value.

[0058] 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 complex calculation, and 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.

[0059] Specifically, the main electrode plate 12 includes a first electrode plate 121 and a second electrode plate 122, the first electrode plate 121 and the second electrode plate 122 are triangular structures, the first electrode plate 121 and the second electrode plate 122 can be jointly spliced into a rectangle, and the conductor plate 22 is arranged opposite to the first electrode plate 121 and the second electrode plate 122; the capacitance between the conductor plate 22 and the first electrode plate 121 is C1, and the capacitance between the conductor plate 22 and the second electrode plate 122 is C2; taking the conductor plate 22 moving from bottom to top as an example, C1 linearly decreases, and C2 linearly increases, and the influence of the uncertain distance between the conductor plate 22 and the main electrode plate 12 can be eliminated through the relationship formula (C1-C2) / (C1+C2).

[0060] In the embodiment, the main electrode plate 12 is divided into the first electrode plate 121 and the second electrode plate 122, the capacitance between the conductor plate 22 and the first electrode plate 121 and the capacitance between the conductor plate 22 and the second electrode plate 122 are formed, and the displacement of the conductor plate 22, i.e., the key, can be accurately obtained through corresponding relationship formula operation on the two capacitances, and the accuracy of key detection is improved.

[0061] However, if the conductor plate 22 is twisted relative to the first electrode plate 121 and the second electrode plate 122 during the working process of the key, the twist will cause the equivalent distance between the conductor plate 22 and the first electrode plate 121 to become larger and the equivalent distance between the conductor plate 22 and the second electrode plate 122 to become smaller, the relationship formula (C1-C2) / (C1+C2) cannot offset the influence of the distance between the electrode plates, and using the relationship formula will cause the displacement of the conductor plate 22, i.e., the key, to have a serious error, and the key position detection accuracy is affected.

[0062] Therefore, in order to solve the problem of poor key displacement detection accuracy caused by the twist, in one embodiment, the number of the first electrode plate 121 in the main electrode plate 12 is set to two, as shown in FIG. 7, which is a structure schematic diagram of the main electrode plate 12 in the embodiment, the main electrode plate 12 includes two first electrode plates 121 and one second electrode plate 122; the two first electrode plates 121 are symmetrically arranged on two sides of the second electrode plate 122; one first electrode plate 121 has a first gap with the second electrode plate 122, and the other first electrode plate 121 has a second gap with the second electrode plate 122, and the extension directions of the first gap and the second gap are different from the reciprocating direction.

[0063] The key of the embodiment is provided with the above structure. When the key is pressed or popped out to cause the conductor plate 22 to be twisted, the influence of the twisting of the conductor plate 22 on the capacitances of the two first plates 121 can be offset to each other to reduce the variation of the first capacitance, and the influence of the twisting of the conductor plate 22 on the capacitance of the second plate 122 can also be offset to reduce the variation of the second capacitance, thereby offsetting the capacitance deviation caused by the twisting of the conductor plate 22, improving the accuracy of the capacitance detection, and further improving the accuracy of the key position detection.

[0064] Specifically, the conductor plate 22, the main plate 12 and the auxiliary plate 13 in the key of the embodiment form a capacitance 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. The conductor plate 22 is located on the outer side wall of the shaft 21, and the main plate 12 and the auxiliary plate 13 are located on the inner side wall of the base 11.

[0065] Specifically, the main plate 12 includes two first plates 121 and a second plate 122. The first plates 121 and the second plate 122 are arranged perpendicularly to the reciprocating direction on the same plane, and the two first plates 121 are symmetrically arranged on both sides of the second plate 122. The auxiliary plate 13 is arranged opposite to the main plate 12.

[0066] In order to cause the capacitance signals of the first capacitance and the second capacitance to change when the shaft 21 reciprocates, the length of the first plate 121 in the reciprocating direction and the length of the second plate 122 in the reciprocating direction are both greater than the stroke amount of the conductor plate 22 in the reciprocating direction; so as to ensure that the relative areas of the conductor plate 22 and the first plate 121 and the second plate 122 change when the shaft 21 reciprocates, and the relative area of the conductor plate 22 and the auxiliary plate 13 changes, so that the capacitance signals of the first capacitance and the second capacitance change, and the moving distance of the key can be judged according to the change of the first capacitance and the second capacitance, and the middle position of the key can be determined, thereby improving the accuracy of the key displacement detection.

[0067] Specifically, one first plate 121 and the second plate 122 have a first gap L1, and the other first plate 121 and the second plate 122 have a second gap L2. The extension directions of the first gap L1 and the second gap L2 are different from the reciprocating direction.

[0068] Specifically, the two first polar plates 121 are of the same size and shape, symmetrically arranged on both sides of the second polar plate 122, and symmetrically arranged along the central axis of the second polar plate 122. Therefore, the first gap L1 between one first polar plate 121 and the second polar plate 122 and the second gap L2 between the other first polar plate 121 and the second polar plate 122 are also of the same size and shape, and the first gap L1 and the second gap L2 are symmetrically arranged along the central axis of the second polar plate 122, and the direction of the central axis of the second polar plate 122 is the same as the direction of the reciprocating motion of the mandrel 21.

[0069] Specifically, the extension directions of the first gap L1 and the second gap L2 are different from the direction of the reciprocating motion of the mandrel 21, that is, the first gap L1 has an included angle with the direction of the reciprocating motion of the mandrel 21, and the second gap L2 also has a symmetrical included angle with the direction of the reciprocating motion of the mandrel 21. When the conductor plate 22 follows the mandrel 21 to reciprocate, the first capacitor and the second capacitor both change. According to the change of the first capacitor and the second capacitor, the displacement of the conductor plate 22 can be determined, and thus the displacement of the key can be determined.

[0070] As shown in FIG. 8, it is a structure schematic diagram of the capacitor structure of the embodiment when it is twisted. The dashed line is the central axis of the second polar plate 122, and the conductor plate 22 rotates around the dashed line. When the conductor plate 22 twists during the movement of the mandrel 21, the distance between A and the first polar plate 121 is large, and the distance between D and the other first polar plate 121 is small. The distances between the points A, B, C, D in the conductor plate 22 and the main polar plate 12 are large-medium large-medium small-small in turn. For the A and D points, their opposite positions are the first polar plate 121, so the effects of twisting cancel each other out. Similarly, the effects of twisting at B and C also cancel each other out. Moreover, it can be approximately considered that the equivalent distances between the two first polar plates 121 and the conductor plate 22 and the equivalent distances between the second polar plate 122 and the conductor plate 22 are equal to the equivalent distance between the O point on the central axis and the conductor plate 22, thereby compensating for the effects of twisting and improving the accuracy of capacitor detection, and further improving the accuracy of key displacement detection.

[0071] Specifically, the two first polar plates 121 and the second polar plate 122 together form a cuboid; the lengths of the first gap L1 and the second gap L2 in the direction of the reciprocating motion of the mandrel 21 are equal to the length of the polar plate assembly in the direction of the reciprocating motion of the mandrel 21; the lengths of the first gap L1 and the second gap L2 in the target direction are equal to half the width of the polar plate assembly in the target direction; and the target direction is perpendicular to the direction of the reciprocating motion of the mandrel 21 and parallel to the surface of the main polar plate 12 close to the conductor plate.

[0072] In one embodiment, in one pole plate assembly, the first gap L1 and the second gap L2 extend in a straight line, as shown in FIG. 7. From bottom to top, the distance between the first gap L1 and the second gap L2 linearly increases, and the first gap L1 and the second gap L2 form a V shape. Specifically, the first gap L1 extends in a straight line from the midpoint of the bottom edge of the cuboid to the left top corner of the cuboid, and the second gap L2 extends in a straight line from the midpoint of the bottom edge of the cuboid to the right top corner of the cuboid. In this embodiment, by setting the extension direction of the first gap L1 and the second gap L2 as a straight line, when the conductor plate 22 moves along the reciprocating direction of the mandrel 21, the change of the facing area of the conductor plate 22 and the first pole plate 121 and the second pole plate 122 tends to be linear, and the change of the relationship (C1-C2) / (C1+C2) is only related to the change of the facing area. By the relationship (C1-C2) / (C1+C2), not only the influence of the distance between the pole plates can be offset, but also the change of the relationship (C1-C2) / (C1+C2) tends to be linear with the change of the facing area, thereby further improving the accuracy of the capacitance detection and further improving the accuracy of the position detection of the key.

[0073] In other embodiments, the extension direction of the first gap L1 and the second gap L2 can be a curve, and the distance between the first gap L1 and the second gap L2 only needs to gradually increase from bottom to top along the reciprocating direction, for example, the first gap L1 and the second gap L2 form a U shape.

[0074] Specifically, in the case of small torsion, i.e., the torsion distance of the conductor plate 22 is much smaller than the distance between the pole plates, the relationship (C1-C2) / (C1+C2) is close to the case without torsion, and the influence of the torsion of the conductor plate 22 on the relationship (C1-C2) / (C1+C2) can be ignored. Therefore, in the case of small torsion of the conductor plate 22, the relationship (C1-C2) / (C1+C2) can still offset the influence of the distance between the pole plates by the key structure described above, thereby improving the accuracy of the capacitance detection and further improving the accuracy of the position detection of the key.

[0075] However, when the torsion distance of the conductor plate 22 is large, the accuracy of the structure with two first pole plates 121 and one second pole plate 122 will be reduced, and some situations cannot be completely compensated. Therefore, in order to solve the problem of low key detection accuracy caused by large torsion and further improve the accuracy of the key displacement detection, one embodiment of the present application further forms one pole plate assembly with two first pole plates 121 and one second pole plate 122, and the main pole plate 12 includes a plurality of pole plate assemblies.

[0076] As shown in FIG. 9, a schematic diagram of the structure of the main pole plate 12 of the present embodiment is shown, the main pole plate 12 comprises a plurality of pole plate assemblies 120, the plurality of pole plate assemblies 120 are arranged on the inner side wall of the base, and the plurality of pole plate assemblies 120 are arranged in a direction perpendicular to the reciprocating motion direction; in the two adjacent pole plate assemblies 120, the first pole plate 121 of one pole plate assembly 120 is adjacent to and integrally arranged with the first pole plate 121 of the other pole plate assembly 120.

[0077] In the present embodiment, by arranging a plurality of pole plate assemblies 120 in the main pole plate 12, in the case of determining the space inside the key, as many pole plate assemblies 120 as possible are arranged, and the space occupied by each pole plate assembly 120 in the arrangement direction is as small as possible. In the case of torsion of the conductor plate 22, the torsion between the conductor plate 22 and each pole plate assembly 120 is greatly reduced relative to the overall torsion, thereby further eliminating the capacitance deviation caused by the torsion of the conductor plate 22 and each pole plate assembly 120, thereby improving the accuracy of overall capacitance detection and improving the accuracy of position detection. It is worth mentioning that the more the number of pole plate assemblies 120, the closer the conductor plate 22 and each pole plate assembly 120 are to the parallel state, the better the effect of eliminating the capacitance deviation caused by the torsion, and the higher the accuracy of the key displacement detection.

[0078] Specifically, the first pole plate 121 and the second pole plate 122 are arranged alternately, which can offset the influence of the torsion of the shaft 21. The extension direction of the first gap L1 and the second gap L2 is a straight line, and in the case of a plurality of pole plate assemblies 120, the plurality of first gaps L1 and the plurality of second gaps L2 are in a W shape. The W-shaped main pole plate 12 can further improve the compensation effect. In the present embodiment, by setting the extension direction of the first gap L1 and the second gap L2 as a straight line and setting the W-shaped main pole plate 12, when the conductor plate 22 moves along the reciprocating motion 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 change linearly, and the arrangement of the plurality of pole plate assemblies 120 offsets the influence of the torsion on the capacitance, and the change of the relationship (C1-C2) / (C1+C2) is related to the change of the facing area as much as possible, so that the relationship (C1-C2) / (C1+C2) changes 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.

[0079] It can be seen that the three main plate 12 structures shown in FIG. 6, FIG. 7, FIG. 9 are all divided into two types of plates, i.e. the first plate 121 and the second plate 122. The first plate 121 of each column of keys is connected to a first detection pin of the detection circuit 20, and the second plate 122 of each column of keys is connected to a second detection pin of the detection circuit 20, so that the detection circuit 20 can obtain two capacitances, i.e. the first capacitance and the second capacitance when detecting a key, thereby determining the pressing condition of the key through the first capacitance and the second capacitance, and improving the accuracy of key detection.

[0080] As shown in FIG. 10, it is an equivalent circuit diagram of the key detection system of the embodiment. The key detection system of the embodiment includes a driving circuit 10, a detection circuit 20 and a plurality of keys. The plurality of keys are arranged in an N*M matrix, and N and M are both integers greater than 0. The driving circuit 10 includes N driving pins, i.e. 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. In FIG. 10, N is 3 and M is 2, which may include vacant keys to meet the actual needs, but the vacant keys do not affect the implementation of the embodiment and still meet the needs of key detection.

[0081] Specifically, the dashed box in FIG. 10 represents a key. The capacitor C1 in the dashed box represents a first capacitor formed by the conductor plate 22, the auxiliary plate 13 and the first plate 121 of the main plate 12. The capacitor C2 in the dashed box represents a second capacitor formed by the conductor plate 22, the auxiliary plate 13 and the second plate 122 of the main plate 12. The keys are arranged according to the order of rows and columns. Among them, the auxiliary plate 13 of each row of keys is commonly connected to a driving pin of the driving circuit 10. The first plate 121 of the main plate 12 of each column of keys is commonly connected to a first detection pin of the detection circuit 20. The second plate 122 of the main plate 12 of each column of keys is commonly connected to a second detection pin of the detection circuit 20.

[0082] That is, the driving pin Tx1 of the driving circuit 10 is connected with the sub-plate 13 of the button 1_1 and the button 1_2, the driving pin Tx2 of the driving circuit 10 is connected with the sub-plate 13 of the button 2_1, and the driving pin Tx3 of the driving circuit 10 is connected with the sub-plate 13 of the button 3_1 and the button 3_2; the first detection pin Rx11 of the detection circuit 20 is connected with the first plate 121 of the main 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 with the second plate 122 of the main 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 with the first plate 121 of the main 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 with the second plate 122 of the main plate 12 of the button 1_2 and the button 3_2.

[0083] Specifically, each detection circuit 20 includes a plurality of detection units, each detection unit is connected with a first detection pin or a second detection pin, and each detection unit is used to obtain a first capacitance or a second capacitance, so as to realize the detection of the capacitance signal. Wherein, the first detection pin and the second detection pin are staggered, and the first plate 121 and the second plate 122 of the main plate 12 of the same button are connected to adjacent first detection pins and second detection pins, that is, the adjacent first detection pins and second detection pins of the detection circuit 20 can obtain the first capacitance and the second capacitance of the same button, so as to facilitate the acquisition of the capacitance signal and the calculation of the displacement amount of the button.

[0084] Specifically, when the driving circuit 10 drives the sub-plate 13 to work through the driving pin, the sub-plate 13 can work at the same time or in time-sharing mode, that is, the detection circuit 20 receives the signal in real time, and the driving circuit 10 can scan in time-sharing mode or at the same time.

[0085] Taking time-sharing work as an example, the driving circuit 10 sends the driving signal in time-sharing manner. When the driving circuit 10 sends the driving signal through the driving pin Tx1, the auxiliary plate 13 of the first row of the keys 1_1 and 1_2 starts to work, and the keys of other rows do not work. The first detection pin Rx11 and Rx21 of the detection circuit 20 respectively receive the capacitance signals of the first capacitors of the keys 1_1 and 1_2, and the second detection pin Rx12 and Rx22 of the detection circuit 20 respectively receive the capacitance signals of the second capacitors of the keys 1_1 and 1_2. 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 change of the first capacitor and the second capacitor, it can be determined that the key 1_1 is pressed and the displacement of the key 1_1. The pressing of the key 1_2 is similar, which will not be described here. The pressing state of all the keys in the first row is obtained by this method, so as to determine the corresponding indication of the user. Then, the driving pin Tx1 of the driving circuit 10 stops sending the signal, and the driving circuit 10 sends the driving signal through the driving pin Tx2. In this way, the whole scanning process is completed. In the arrangement of the whole circuit, the vacancy is allowed to exist, and the detection effect is not affected.

[0086] Specifically, the circuit structure described above is used to obtain the capacitance information, and the current real-time displacement of the key is obtained by calculating and processing the capacitance data. At a certain moment, when the displacement exceeds a certain threshold, a certain 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, no action when the displacement is 0; type small a when the displacement is between 0.5mm and 2mm; type capital A when the displacement exceeds 2mm. Further, there can be more levels of triggering application scenarios, such as: the A key is designed as an accelerator key in a game. The deeper the pressing, the deeper the accelerator pedal is pressed. Pressing to the bottom is equivalent to pressing the accelerator pedal to the bottom. Since the capacitance key of the embodiment has high linearity and high resolution, the process of pressing the accelerator pedal can be well simulated, and the user experience is improved.

[0087] Specifically, all the keys in the full keyboard can only partially use the above-mentioned capacitive key. For example, the special part of the key uses the above-mentioned capacitive key. For other positions, ordinary keys can be used instead, and only the corresponding processing on the circuit and software is needed. For each capacitive key, the trigger threshold and function can be independently set to improve the flexibility of the key.

[0088] Specifically, for a high-performance capacitance detection chip, such as a CHCT5562 chip, a complete scanning cycle can be achieved within 10 ms, so that the reporting rate of each capacitive key can reach more than 100 Hz; if it is necessary to further improve the reporting rate, a simultaneous scanning mode can also be used.

[0089] The circuit connection mode of the embodiment corresponds to the arrangement mode of the entire circuit and the arrangement mode of the key structure, the auxiliary electrode plate 13 of each row of keys shares one driving pin, the first electrode plate 121 of the main electrode plate 12 of each column of keys shares one first detection pin, and the second electrode plate 122 of the main electrode plate 12 of each column of keys shares one second detection pin, which not only simplifies the complexity of the circuit and saves the cost of the circuit, but also improves the accuracy of the key displacement detection by the first capacitor and the second capacitor.

[0090] Specifically, the capacitive sensing key of the embodiment further includes a shaft seat 3, the main electrode plate 12 includes a first pin pin1, a second pin pin2 and a ground pin GND, the auxiliary electrode plate 13 includes a third pin pin3, and the first pin pin1, the second pin pin2, the third pin pin3 and the ground pin GND penetrate the bottom of the base 11 and are connected to the corresponding interfaces on the shaft seat 3; the movement assembly 2 of the embodiment further includes a cover plate 23, the cover plate 23 includes a hollow region, the cover plate 23 covers the shaft 21, and the top surface of the shaft 21 is exposed to the surface of the cover plate 23 through the hollow region.

[0091] Specifically, the shaft seat 3 includes a first interface, a second interface and a third interface, as shown in FIG. 11, which is a structure diagram of the shaft seat 3 in the capacitive sensing key corresponding to FIG. 1 in the embodiment, as shown in FIG. 12, which is a structure diagram of the shaft seat 3 encapsulating an SMT patch in the capacitive sensing key corresponding to FIG. 1 in the embodiment, as shown in FIG. 13, which is a structure diagram of the shaft seat 3 in the capacitive sensing key corresponding to FIG. 3 in the embodiment, and as shown in FIG. 14, which is a structure diagram of the shaft seat 3 encapsulating an SMT patch in the capacitive sensing key corresponding to FIG. 3 in the embodiment.

[0092] Specifically, the shaft seat 3 includes a first interface a, a second interface b and a third interface c, the auxiliary electrode plate 13 and the first electrode plate 121 and the second electrode plate 122 in the main electrode plate 12 are fixed to the base 11 by means of glue or buckles, and the bottom pin positions of the auxiliary electrode plate 13, the first electrode plate 121 and the second electrode plate 122 are extended out of the base 11, so as to facilitate subsequent connection with the shaft seat 3; wherein a plurality of first electrode plates 121 share one first pin pin1, a plurality of second electrode plates 122 share one second pin pin2, and the auxiliary electrode plate 13 has a third pin pin3.

[0093] As shown in the two capacitive sensing keys of FIG. 1 and FIG. 3, the main plate 12 includes a first pin pin1 and a second pin pin2, the auxiliary plate 13 includes a third pin pin3, the first interface a is connected to the first pin pin1, the first pin pin1 is connected to each first plate 121 of the main plate 12; the second interface b is connected to the second pin pin2, the second pin pin2 is connected to each second plate 122 of the main plate 12; the third interface c is connected to the third pin pin3.

[0094] Specifically, the back of the main plate 12 is paved, that is, the side of the main plate 12 away from the conductor plate 22 is paved, which plays a role of shielding interference signals, so the main plate 12 further includes a ground pin GND, and the corresponding shaft seat 3 further includes a ground port GND1, and the ground pin GND of the main plate 12 is connected to the ground port GND1 of the shaft seat 3. The shaft seat 3 is provided with a plurality of surface mount technology (SMT) patches, which are respectively connected to the first interface a, the second interface b, the third interface b and the ground port GND1. Among them, 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.

[0095] Specifically, the positions of the plurality of interfaces on the shaft seat 3 correspond to the pin positions of the main plate 12 and the auxiliary plate 13. For example, the interfaces and SMT patches of the shaft seat 3 corresponding to FIG. 1 and FIG. 11 and FIG. 12, and the interfaces and SMT patches of the shaft seat 3 corresponding to FIG. 3 and FIG. 13 and FIG. 14. In practice, the pin positions of the main plate 12 and the auxiliary plate 13 can be set according to the pin positions of the main plate 12 and the auxiliary plate 13, so that the pins of the main plate 12 and the auxiliary plate 13 are directly connected to the corresponding interfaces on the shaft seat 3 after penetrating the base 11, thereby minimizing the pin length and reducing the size of the key.

[0096] Specifically, the shaft seat 3 is fixed to the main circuit board by SMT technology. After the conductive pins at the lower end of the main plate 12 and the auxiliary plate 13 are inserted into the shaft seat 3, the pins are connected to the main circuit board to form a capacitive loop, so as to detect the change of the first capacitor and the second capacitor, thereby realizing the detection of the displacement of the key. This scheme is simple and reliable, low in cost, and can realize hot plug function.

[0097] Specifically, the conductor plate 22 is generally made of conductive metal, and the conductor plate 22 is fixed on the mandrel 21 to form a complete structure and move up and down with the mandrel 21; the auxiliary plate 13 can be manufactured by metal stamping; the main plate 12 can be manufactured by using a PCB board, or can be manufactured by using an FPC or a metal sheet.

[0098] Specifically, the driving circuit 10 and the detection circuit 20 of the key detection system in the embodiment can be provided by a chip, as shown in FIG. 15, which is a schematic diagram of the connection 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 general purpose input output (GPIO), inter integrated circuit (I2C), improved inter integrated circuit (I3C), or serial peripheral interface (SPI).

[0099] Specifically, the chip 201 can be a CHCT5562 chip, which provides driving pins and detection pins of the driving circuit. The CHCT5562 chip is connected with the host computer 202 and is controlled and calculated by the host computer 202. The host computer 202 can be the main control chip of the keyboard. The CHCT5562 chip transmits the pressing state of all the keys to the host computer 202 for subsequent processing, including determining the pressed key and the pressing displacement of the key according to the capacitance.

[0100] Specifically, the CHCT5562 chip itself has a micro controller unit (MCU) and multiple communication interfaces, and can be used as a host computer 202 to control other chips. The CHCT5562 chip itself can be used as a main control chip + capacitance detection chip, which saves cost. As shown in FIG. 16, which is a structural schematic diagram of the CHCT5562 chip, including a micro controller 50, a communication interface 60, and a capacitance digital signal processing module 70.

[0101] Specifically, the CHCT5562 chip has 20 driving pins and 42 detection pins, which is a high-performance capacitance detection chip. Therefore, only one CHCT5562 chip is needed to realize the key detection of the full keyboard. According to the detection principle, the state of all keys can be measured, processed, and displayed in real time, which naturally realizes full-key non-conflict without additional processing.

[0102] Take CHCT5562 chip as the main control chip + capacitor detection chip, and take the extra control of light emitting diode (LED) as an example for description. The emitter plate 30 sends a specific voltage and current signal, which is controlled by the capacitor digital signal processing module 70. After the receiving plate 40 receives the electric signal, the signal 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 moment, the information is transmitted to the host computer such as a computer host through the communication interface 60, and the host computer makes a corresponding action, for example, types the letter "A". At the same time, after the "A" key is pressed, the information is processed by the microcontroller 50 and transmitted to the LED lamp control chip through the communication interface 60. After the LED lamp chip receives the signal, the LED lamp of the A key is turned on. It should be noted that the emitter plate 30 is the auxiliary 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.

[0103] Another aspect of the embodiment of the present application also provides an electronic device, comprising the key detection system described above.

[0104] Compared with the related art, the electronic device provided in the embodiment of the present application is provided with the key detection system provided in the foregoing embodiment, and therefore has the technical effects provided in the foregoing embodiment, which will not be described herein.

[0105] The division of the above various components is only for clear description, and in implementation, one component can be combined or some components can be split or decomposed into multiple components, as long as the same logical relationship is included, which is within the protection scope of the embodiment.

[0106] Another embodiment of the present application relates to a key detection method applied to the key detection system described above, and the method comprises: detecting a capacitor signal generated by a target capacitor; and determining a pressing condition of a key according to a change of the capacitor signal.

[0107] Specifically, the pressing condition includes whether the keyboard is pressed and a displacement amount of the key pressing, and the moving distance of the key is determined according to the change of the capacitor signal, which is specifically described in the above embodiment and will not be described herein.

[0108] The step division of the above various methods is only for clear description, and in implementation, one step can be combined or some steps can be split or decomposed into multiple steps, as long as the same logical relationship is included, which is within the protection scope of the present application; adding irrelevant modifications or introducing irrelevant designs in the algorithm or flow, but not changing the core design of the algorithm and flow, are within the protection scope of the present application.

[0109] Another embodiment of the present application relates to a computer readable storage medium storing a computer program. The computer program is executed by a processor to implement the method embodiments.

[0110] That is, a person skilled in the art can understand that all or part of the steps of the above-mentioned method embodiments can be completed by instructing relevant hardware through a program stored in a storage medium, and the program includes a plurality of instructions for causing an apparatus (which can be a single-chip microcomputer, a chip, etc.) or a processor to execute all or part of the steps of the various embodiments of the method of the present application. The aforementioned storage medium includes a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various media that can store program codes.

[0111] A person skilled in the art can understand that the above-mentioned embodiments are specific embodiments for implementing the present application, and in actual applications, various changes can be made in form and details without departing from the spirit and scope of the present application.

Claims

1. A key detection system, comprising: Key, driving circuit, detection circuit; The key comprises a base and a moving component; the moving component penetrates through the top surface of the base and reciprocally moves perpendicular to the top surface; the moving component comprises a mandrel and a conductor plate fixed opposite to the mandrel; The base comprises a pedestal, a main electrode plate and a secondary electrode plate fixed opposite to the pedestal; the conductor plate is arranged opposite to the main electrode plate and the secondary electrode plate respectively; The secondary electrode plate, the conductor plate and the main electrode plate form a target capacitor; in the case of reciprocating movement of the mandrel, the capacitance signal of the target capacitor changes; The driving circuit is connected to the secondary electrode plate, and the detection circuit is connected to the main electrode plate; the driving circuit is used to drive the secondary electrode plate to work, and the detection circuit is used to detect the target capacitor.

2. The key detection system of claim 1, wherein, The number of keys is multiple, and the multiple keys are arranged in an N*M matrix, wherein N and M are both integers greater than 0; the driving circuit comprises N driving pins, and the detection circuit comprises M detection pins; The secondary electrode plates of the keys in each row are commonly connected to one driving pin of the driving circuit; The main electrode plates of the keys in each column are commonly connected to one detection pin of the detection circuit.

3. The key detection system of claim 1, wherein, The main electrode plate comprises a first electrode plate and a second electrode plate; the secondary electrode plate, the conductor plate and the first electrode plate form a first capacitor, and the secondary electrode plate, the conductor plate and the second electrode plate form a second capacitor; In the case of reciprocating movement of the mandrel, the capacitance signals of the first capacitor and the second capacitor change; The detection circuit is connected to the first electrode plate and the second electrode plate of the main electrode plate; the detection circuit is used to detect the first capacitor and the second capacitor.

4. The key detection system of claim 3, wherein, The main electrode plate comprises two first electrode plates, which are symmetrically arranged on both sides of the second electrode plate; one first electrode plate has a first gap with the second electrode plate, and the other first electrode plate has a second gap with the second electrode plate; the extension directions of the first gap and the second gap are different from the reciprocating movement direction.

5. The key detection system of claim 4, wherein, The two first electrode plates and one second electrode plate form an electrode plate assembly, and the main electrode plate comprises multiple electrode plate assemblies; the multiple electrode plate assemblies are arranged on the inner side wall of the pedestal, and the multiple electrode plate assemblies are arranged along the direction perpendicular to the reciprocating movement direction; in the two adjacent electrode plate assemblies, the first electrode plate of one electrode plate assembly is adjacent to and integrally arranged with the first electrode plate of the other electrode plate assembly.

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

7. The key detection system of any one of claims 1 to 5, wherein, The number of the conductor plates is two, and the two conductor plates are arranged on different outer side walls of the mandrel respectively; and the two conductor plates are connected through wires. The auxiliary pole plate and the main pole plate are arranged on different inner side walls of the base, the auxiliary pole plate is arranged opposite to one of the conductor plates, and the main pole plate is arranged opposite to another of the conductor plates.

8. An electronic device comprising: The key detection system according to any one of claims 1 to 7. 9.A key detection method applied to the key detection system according to any one of claims 1 to 7, the method comprising: detecting a capacitance signal generated by the target capacitor; determining a pressing condition of the key according to a change of the capacitance signal. 10.A computer readable storage medium storing a computer program, the computer program being executed by a processor to implement the key detection method according to claim 9.

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