Capacitive sensing type key and device

Abstract

The embodiment of the utility model relates to a key structure, and discloses a capacitive sensing type key and equipment. The capacitive sensing type key comprises an upper cover, a base, a shaft core, an elastic piece and a capacitor module, the shaft core penetrates through the top surface of the upper cover and reciprocates in a manner of being perpendicular to the top surface; the center of the shaft core extends towards the base to form a guide rail column; the base comprises a guide rail channel formed by extending the guide rail column to the upper cover, and the shaft core reciprocates to drive the guide rail column to reciprocate in the guide rail channel. The capacitor module comprises a first polar plate and a second polar plate which are arranged on the inner wall of the guide rail channel at an interval, and the projection of the first polar plate in the direction of the second polar plate is partially overlapped with the second polar plate; the first pole plate and the second pole plate form a capacitor, when the guide rail column reciprocates between the first pole plate and the second pole plate, capacitance signals generated by the capacitor change accordingly, and the moving distance of the shaft core can be determined according to the capacitance signals.

Description

Technical Field

[0001] The embodiments of the utility model relate to a key structure, and in particular to a capacitive induction key and device. Background Art

[0002] In a conventional mechanical key, when not pressed, the ridge of the shaft core presses against the moving plate, separating it from the stationary plate and disconnecting the circuit. When the shaft core is pressed, the ridge separates from the moving plate, and the moving plate rebounds and contacts the stationary plate, completing the circuit. This circuit continuity is used to detect the key state.

[0003] The inventors have found that conventional mechanical keys have at least the following problems: conventional mechanical keyboards can only detect the on / off state and cannot implement functions such as key travel adjustment. In addition, due to oxidation and wear of the contacts, the lifespan is relatively short. Utility Model Content

[0004] The purpose of the embodiments of the present utility model is to provide a capacitive sensing button and device, which enables the button to achieve multi-state monitoring, and based on structural improvements, avoids contact wear and improves the life of the button.

[0005] To solve the above technical problems, an embodiment of the present invention provides a capacitive sensing key, comprising: an upper cover, a base matching the upper cover, a shaft core, an elastic member, and a capacitor module; the shaft core passes through the top surface of the upper cover and reciprocates perpendicularly to the top surface; the center of the shaft core extends toward the base to form a guide rail column; the base includes: a guide rail channel formed along the guide rail column extending toward the upper cover, and the reciprocating movement of the shaft core drives the guide rail column to reciprocate within the guide rail channel; one end of the elastic member abuts against the shaft core, and the other end of the elastic member abuts against the base; when the shaft core is moved by an external force from its initial position, the shaft core applies a force to the elastic member, and when the external force is removed, the elastic member restores the shaft core to its initial position; the capacitor module includes: a first electrode plate and a second electrode plate disposed on the inner wall of the guide rail channel, the first electrode plate and the second electrode plate being spaced apart, and the projection of the first electrode plate toward the second electrode plate partially overlaps with the second electrode plate; wherein the first electrode plate and the second electrode plate form a capacitor, and when the guide column reciprocates between the first electrode plate and the second electrode plate, the capacitance signal generated by the capacitor changes accordingly.

[0006] An embodiment of the present utility model further provides an electronic device, comprising: a housing and a plurality of the above-mentioned capacitive induction buttons arranged in the housing.

[0007] Compared with the related art, the embodiment of the present invention uses the guide rail column originally existing in the key as a structure to trigger the change of the capacitance of the capacitor module during the key pressing process. The first electrode plate and the second electrode plate of the capacitor module are arranged on the inner wall of the guide rail channel, and the projection of the first electrode plate in the direction of the second electrode plate partially overlaps with the second electrode plate to form a capacitor. When the key shaft core is reciprocated by an external force, the guide rail column will reciprocate in the guide rail channel. Since the guide rail column will partially block the first electrode plate and the second electrode plate in the guide rail channel, the blocked area will change with the movement of the guide rail column. The dielectric constant of the guide rail column is different from the dielectric constant of air. Therefore, the reciprocating movement of the guide rail column will change the size of the capacitance signal generated by the capacitor. The movement distance of the guide rail column can be calculated based on the change of the capacitance signal. Since there is a corresponding relationship between the movement distance of the guide rail column and the movement distance of the shaft core, the movement distance of the shaft core can be known after the movement distance of the guide rail column is determined, thereby realizing the monitoring of any distance of key movement. In addition, the movement distance of the shaft core is detected by the cooperation of the capacitor module and the guide rail column. There is no direct contact and friction between the components between the capacitor module and the guide rail column. Therefore, the wear between the components can be reduced and the service life of the key can be increased.

[0008] In addition, the number of second pole plates is two. When the axis core reciprocates perpendicular to the top surface, the first change in the area facing each other of the guide rail column and one of the second pole plates is the same as the second change in the area facing each other of the guide rail column and the other of the second pole plates.

[0009] In addition, the first electrode plate and the second electrode plate are arc-shaped, and the shapes of the first electrode plate and the second electrode plate are consistent with the shape of the inner wall of the guide rail channel.

[0010] In addition, the cross-sectional center of the guide rail channel coincides with the cross-sectional center of the guide rail column in the moving direction of the shaft core.

[0011] In addition, the cross section of the guide rail column is circular, and the cross section of the guide rail channel is a circular ring.

[0012] In addition, there is an accommodating space surrounding the guide rail column, and the elastic member is disposed in the accommodating space.

[0013] In addition, the elastic member is a metal spring.

[0014] In addition, the elastic member is located at the periphery of the first electrode plate and the second electrode plate, and is arranged around the first electrode plate and the second electrode plate.

[0015] In addition, the guide rail post is made of a metal material or a non-metal material with electrical conductivity greater than a threshold. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] One or more embodiments are exemplarily illustrated by pictures in the corresponding drawings. These exemplifications do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings are represented as similar elements. Unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0017] Figure 1 This is an exploded view of a capacitive sensing button provided by the utility model;

[0018] Figure 2 This is a cross-sectional view of a capacitive sensing button provided by the utility model;

[0019] Figure 3 This is a structural diagram of a capacitor module provided by the utility model;

[0020] Figure 4 This is a structural diagram of another capacitor module provided by the utility model;

[0021] Figure 5 This is a simplified structural diagram of a capacitive induction button provided by the present invention before being subjected to external force;

[0022] Figure 6 This is a simplified structural diagram of a capacitive induction button provided by the utility model after being subjected to external force;

[0023] Figure 7 It is a cross-sectional view of another capacitive induction key provided by the utility model. DETAILED DESCRIPTION

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more apparent, the following detailed description of the embodiments of the present invention is provided in conjunction with the accompanying drawings. However, those skilled in the art will appreciate that many technical details are provided in the embodiments of the present invention to facilitate a better understanding of the present invention. However, even without these technical details and the various variations and modifications based on the following embodiments, the technical solutions claimed in the present invention can still be achieved.

[0025] The following embodiments are divided for the convenience of description and should not constitute any limitation on the specific implementation of the present invention. The various embodiments can be combined with each other and referenced to each other under the premise of no contradiction.

[0026] An embodiment of the utility model relates to a capacitive induction keypad, comprising: an upper cover, a base matching the upper cover, a shaft core, an elastic member, and a capacitor module; the shaft core penetrates the top surface of the upper cover and reciprocates perpendicularly to the top surface; the center of the shaft core extends toward the base to form a guide rail column; the base comprises: a guide rail channel formed along the guide rail column extending toward the upper cover, and the reciprocating movement of the shaft core drives the guide rail column to reciprocate within the guide rail channel; one end of the elastic member abuts against the shaft core, and the other end of the elastic member abuts against the base; when the shaft core is moved by an external force from its initial position, the shaft core applies a force to the elastic member, and when the external force is removed, the elastic member restores the shaft core to its initial position; the capacitor module comprises: a first electrode plate and a second electrode plate arranged on the inner wall of the guide rail channel, the first electrode plate and the second electrode plate being spaced apart, and the projection of the first electrode plate toward the second electrode plate partially overlaps with the second electrode plate; wherein the first electrode plate and the second electrode plate form a capacitor, and when the guide rail column reciprocates between the first electrode plate and the second electrode plate, the capacitance signal generated by the capacitor changes accordingly. The key can achieve multi-state monitoring, and based on the structural improvement, it avoids the wear of the contact and increases the life of the key. The following is a detailed description of the implementation details of the capacitive sensing key of this embodiment. The following content is only for the convenience of understanding and is not required for the implementation of this solution.

[0027] A capacitive sensing button in an embodiment of the present invention, such as Figure 1 As shown, the capacitive sensing key includes: an upper cover 10, a base 20 matching the upper cover 10, a shaft core 30, an elastic member 40 and a capacitor module 50; the shaft core 30 passes through the top surface of the upper cover 10, and the portion of the shaft core 30 exposed on the top surface of the upper cover 10 is used to install the keycap, which can be touched by the user to press the key. When the keycap is subjected to external force, the shaft core 30 moves perpendicularly to the top surface toward the inside of the key. When the external force on the keycap is removed, the shaft core 30 returns to its original position under the action of the elastic member 40, that is, the shaft core 30 moves perpendicularly to the top surface toward the outside of the key until it returns to its original position. The distance the shaft core 30 moves is related to the magnitude of the external force. The greater the external force, the greater the distance the shaft core 30 moves toward the inside of the key.

[0028] like Figure 2 As shown, the center of the shaft core 30 extends toward the base 20 to form a guide rail column 31; the base 20 includes: a guide rail channel 21 extending along the guide rail column 31 toward the upper cover 10, and the reciprocating motion of the shaft core 30 drives the guide rail column 31 to reciprocate in the guide rail channel 21; one end of the elastic member 40 is against the shaft core 30, and the other end of the elastic member 40 is against the base 20; when the shaft core 30 is moved by an external force in its initial position, the shaft core 30 applies a force to the elastic member 40, and when the external force is removed, the elastic member 40 restores the shaft core 30 to its initial position.

[0029] like Figure 3 As shown, the capacitor module includes: a first electrode plate 51 and a second electrode plate 52 arranged on the inner wall of the guide rail channel, the first electrode plate 51 and the second electrode plate 52 are arranged at intervals, and the projection of the first electrode plate 51 in the direction of the second electrode plate 52 partially overlaps with the second electrode plate 52; wherein, the first electrode plate 51 and the second electrode plate 52 form a capacitor, and, when the guide rail column reciprocates between the first electrode plate 51 and the second electrode plate 52, the capacitance signal generated by the capacitor changes accordingly.

[0030] The capacitor module may further include a plurality of second plates 52. For example, the capacitor module includes two second plates 52. Figure 4 As shown, the first electrode plate 51 forms a capacitor with one of the second electrode plates 52, and the first electrode plate 51 forms another capacitor with the other second electrode plate 52. The two second electrode plates 52 are of complementary design, that is, when the shaft core reciprocates perpendicular to the top surface, the first change in the area facing the guide post and one of the second electrode plates is the same as the second change in the area facing the guide post and the other second electrode plate. When the area facing the guide post and one of the second electrode plates increases, the area facing the guide post and the other second electrode plate decreases, and the increase in the area facing the guide post and one of the second electrode plates is the same as the decrease in the area facing the guide post and the other second electrode plate. Such a design can facilitate the subsequent processing and calculation of the signals generated by the multiple capacitors. Similarly, if N second electrode plates 52 are provided, the N second electrode plates 52 and the first electrode plate 51 form N capacitors, and the movement distance of the shaft core is calculated based on the changes in the capacitance signals generated by the N capacitors.

[0031] Regarding the positioning of the elastic member 40, there is an accommodation space surrounding the guide rail post 31, and the elastic member is disposed within the accommodation space. That is, the elastic member 40 is located around the guide rail post 31 and the guide rail channel 21, and is disposed around the guide rail post 31 and the guide rail channel 21. Since the first and second plates 51, 52 of the capacitor module are disposed on the inner wall of the guide rail channel 21, the elastic member 40 is also located around the first and second plates 51, 52, and is disposed around the first and second plates 51, 52.

[0032] In addition, the first electrode plate 51 and the second electrode plate 52 are arc-shaped, and the shapes of the first electrode plate 51 and the second electrode plate 52 are consistent with the inner wall shape of the guide rail channel 21. The consistent shape can reduce the space occupied by the first electrode plate 51 and the second electrode plate 52, which is conducive to the miniaturization of the button.

[0033] Furthermore, the cross-sectional center of the guide rail channel coincides with the cross-sectional center of the guide rail post in the direction of the axis's motion. The guide rail post has a circular cross-section, while the guide rail channel has a circular cross-section. The first and second plates are symmetrical about the central axis of the guide rail channel, maximizing the area of ​​direct contact between the first and second plates. If there are multiple second plates, the first and second plates are arranged symmetrically, with the axis of symmetry being the central axis of the guide rail channel.

[0034] The elastic member 40 can be a metal spring. When a capacitor is formed between the first electrode plate 51 and the second electrode plate 52, and the first electrode plate 51 serves as the capacitor emitter and the second electrode plate 52 serves as the capacitor receiver, the first electrode plate 51 transmits an electrical signal to the outside world. Part of the electrical signal between the first electrode plate 51 and the second electrode plate 52 is transmitted to the second electrode plate 52 by the guide rail inserted between the first electrode plate 51 and the second electrode plate 52, and another part is directly transmitted to the second electrode plate 52 through the air. Part of the electrical signal generated by the first electrode plate 51 also dissipates outward at both ends of the first electrode plate 51. The electrical signal dissipated outward from both ends of the first electrode plate 51 can be transmitted to the second electrode plate 52 through the metal elastic member 40, thereby preventing electrical signal loss and improving the sensitivity of the capacitor.

[0035] The following describes the key movement distance detection process. Figures 5 and 6 As shown in the figure, it is a simplified structure of the key. Figure 5 As shown, the guide rail post 31 is in the initial position, and the guide rail post 31 slightly overlaps with the first electrode plate 51 and the second electrode plate 52. When the guide rail post 31 is subjected to an external force F, as shown in FIG. Figure 6 As shown, the guide rail post 31 moves in the direction of increasing the area of ​​the first electrode plate 51 and the second electrode plate 52, changing the capacitance signal generated by the capacitance formed by the first electrode plate 51 and the second electrode plate 52. Since the dielectric constant of the guide rail post 31 is greater than the dielectric constant of air, based on the capacitance formula Where C represents capacitance, ε represents dielectric constant, S represents the area facing the first and second plates, d represents the distance between the first and second plates, k represents the electrostatic force constant, and π represents pi. As the area facing the shaft core and the first and second plates 51 and 52 changes, the value of the capacitance signal changes accordingly. The greater the distance the shaft core moves, the greater the change in the capacitance signal. Therefore, based on the change in the capacitance signal, the distance the shaft core moves, and thus the magnitude of the external force, etc., can be determined.

[0036] In addition, in order to make the change of the capacitance signal more obvious, the material of the guide rail column 31 can be changed to a metal material or a non-metal material with a conductivity greater than the threshold. The higher the conductivity, the greater the change in the capacitance signal when the shaft core moves the same distance, and the more convenient it is to process and calculate the capacitance signal. Figure 7As shown, a highly conductive metal medium is added to the guide rail post 31. For example, the interior of the guide rail post 31 can be hollowed out and a highly conductive metal is added in the vacant space to improve the conductivity of the guide rail post 31. Alternatively, a metal wire can be arranged around the outer wall of the guide rail post 31 to improve the conductivity of the guide rail post 31.

[0037] Compared with the related art, the embodiment of the present invention uses the guide rail column originally existing in the key as a structure to trigger the change of the capacitance of the capacitor module during the key pressing process. The first electrode plate and the second electrode plate of the capacitor module are arranged on the inner wall of the guide rail channel, and the projection of the first electrode plate in the direction of the second electrode plate partially overlaps with the second electrode plate to form a capacitor. When the key shaft core is reciprocated by an external force, the guide rail column will reciprocate in the guide rail channel. Since the guide rail column will partially block the first electrode plate and the second electrode plate in the guide rail channel, the blocked area will change with the movement of the guide rail column. The dielectric constant of the guide rail column is different from the dielectric constant of air. Therefore, the reciprocating movement of the guide rail column will change the size of the capacitance signal generated by the capacitor. The movement distance of the guide rail column can be calculated based on the change of the capacitance signal. Since there is a corresponding relationship between the movement distance of the guide rail column and the movement distance of the shaft core, the movement distance of the shaft core can be known after the movement distance of the guide rail column is determined, thereby realizing the monitoring of any distance of key movement. In addition, the movement distance of the shaft core is detected by the cooperation of the capacitor module and the guide rail column. There is no direct contact and friction between the components between the capacitor module and the guide rail column. Therefore, the wear between the components can be reduced and the service life of the key can be increased.

[0038] Another embodiment of the present invention relates to an electronic device, comprising: a housing and a plurality of the above-mentioned capacitive sensing buttons arranged in the housing.

[0039] Compared with the related art, the electronic device provided in this embodiment of the present invention is provided with the capacitive sensing button provided in the aforementioned embodiment. Therefore, it also has the technical effects provided by the aforementioned embodiment, which will not be described in detail here.

[0040] Those skilled in the art will appreciate that the above embodiments are specific embodiments for implementing the present invention, and that in actual applications, various changes may be made in form and detail without departing from the spirit and scope of the present invention.

Claims

1. A capacitive sensing button, characterized in that: include: An upper cover, a base matching the upper cover, an axis core, an elastic member, and a capacitor module; The shaft core passes through the top surface of the upper cover, and the shaft core reciprocates perpendicular to the top surface; The center of the shaft core extends toward the base to form a guide rail column; The base comprises: a guide rail channel extending from the guide rail column toward the upper cover, and the reciprocating motion of the shaft core drives the guide rail column to reciprocate in the guide rail channel; One end of the elastic member abuts against the shaft core, and the other end of the elastic member abuts against the base; when the shaft core is moved by an external force from its initial position, the shaft core applies a force to the elastic member, and when the external force is removed, the elastic member restores the shaft core to its initial position; The capacitor module includes: a first electrode plate and a second electrode plate provided on the inner wall of the guide rail channel, wherein the first electrode plate and the second electrode plate are spaced apart from each other, and a projection of the first electrode plate toward the second electrode plate partially overlaps with the second electrode plate; The first electrode plate and the second electrode plate form a capacitor, and when the guide rail post reciprocates between the first electrode plate and the second electrode plate, the capacitance signal generated by the capacitor changes accordingly.

2. The capacitive induction button according to claim 1, wherein: The number of the second pole plates is two. When the axis core reciprocates perpendicular to the top surface, the first change in the area facing the guide rail column and one of the second pole plates is the same as the second change in the area facing the guide rail column and the other of the second pole plates.

3. The capacitive induction button according to claim 1 or 2, characterized in that: The first electrode plate and the second electrode plate are arc-shaped, and the shapes of the first electrode plate and the second electrode plate are consistent with the shape of the inner wall of the guide rail channel.

4. The capacitive induction button according to claim 1 or 2, characterized in that: The cross-sectional center of the guide rail channel coincides with the cross-sectional center of the guide rail column in the moving direction of the shaft core.

5. The capacitive induction button according to claim 4, characterized in that: The cross section of the guide rail column is circular, and the cross section of the guide rail channel is annular.

6. The capacitive induction button according to claim 1, wherein: An accommodating space is formed around the guide rail post, and the elastic member is disposed in the accommodating space.

7. The capacitive induction button according to claim 6, characterized in that: The elastic member is a metal spring.

8. The capacitive induction button according to claim 6, wherein: The elastic member is located at the periphery of the first electrode plate and the second electrode plate, and is disposed around the first electrode plate and the second electrode plate.

9. The capacitive induction button according to claim 1, wherein: The guide rail post is made of a metal material or a non-metal material with electrical conductivity greater than a threshold.

10. An electronic device, characterized in that: The invention comprises: a shell and a plurality of capacitive induction buttons according to any one of claims 1 to 9 arranged in the shell.

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