Key shaft assembly and keyboard

Abstract

The application provides a key shaft assembly and a keyboard; the keyboard comprises a circuit board and the key shaft assembly; the key shell and the optical flow sensor of the key shaft assembly are fixed on the circuit board; the key shaft assembly comprises a key shell, a shaft core partially inserted into the key shell and in sliding fit with the key shell, an elastic member arranged in the key shell and connected with the shaft core and the key shell respectively, and an optical flow sensor covered by the key shell and arranged on one side of the shaft core and spaced from the shaft core; the shaft core can be driven to move towards a preset direction and make the elastic member store elastic potential energy; the elastic member can release the elastic potential energy to drive the shaft core to move towards a direction opposite to the preset direction; the optical flow sensor can emit laser to the surface of the shaft core and receive the laser signal reflected by the surface of the shaft core to realize the axial position detection of the shaft core; and the key signal is triggered when the axial position of the shaft core reaches a trigger condition.

Description

Technical Field

[0001] This application relates to the field of electronic devices, and more particularly to a key switch assembly and keyboard based on an optical flow sensor. Background Technology

[0002] As a key input tool for human-computer interaction in computers and other electronic devices, the performance and user experience of keyboards are of great concern. Currently, keyboards primarily achieve human-computer interaction through key presses. Based on the key structure and triggering principle, keyboards can be broadly categorized into membrane keyboards, electrostatic capacitive keyboards, mechanical keyboards, magnetic switch keyboards, and optical switch keyboards. Among them, mechanical keyboards are widely popular in many scenarios such as typing, programming, and gaming due to their unique feel and good durability. With the development of technology, magnetic switches, as a new type of mechanical switch, are gradually entering the public eye due to their advantages such as no physical contact wear, fast response speed, and long lifespan. Magnetic switches utilize magnetic force for drive and induction, avoiding the wear and tear problems caused by metal contact friction in traditional mechanical switches. They show great potential in terms of stability and durability, and are especially suitable for professional fields with extremely high requirements for input accuracy and response speed, such as e-sports and industrial control.

[0003] However, existing magnetic switch keyboards still have many shortcomings. Traditional magnetic switches have defects in the stability of the switch core and the precision of magnetic force control, affecting the smoothness of input. In some magnetic switch structures, the switch core is prone to wobbling when moving up and down, which may not only lead to unstable trigger signals and cause misoperations, but also affect the consistent feel of the keys. At the same time, the distribution and intensity control of the magnetic force are not precise enough, which may cause differences in triggering between different keys, reducing the overall performance of the keyboard. The Hall sensors upon which the magnetic axes rely also have some drawbacks: a) They have weak anti-interference capabilities and are easily affected by external magnetic fields (such as stray magnetic fields generated by nearby electronic components), leading to decreased detection accuracy and false triggering or trigger delays; b) They exhibit significant temperature drift, causing the sensor's output signal to deviate when the ambient temperature changes significantly, affecting the stability of the trigger threshold and resulting in inconsistent key responses; c) They exhibit individual consistency deviations, as the sensitivity and output characteristics of different Hall sensors vary slightly due to manufacturing process limitations, causing deviations in the trigger feel and response speed of magnetic axes from the same batch, affecting the overall consistency of the keyboard experience; d) Some low-cost Hall sensors have insufficient resolution, making it difficult to accurately capture subtle changes in the magnetic field, which can easily lead to signal distortion in scenarios requiring extremely high trigger accuracy (such as high-speed continuous keystrokes).

[0004] It should be noted that the information disclosed in the background section of this application is intended to enhance the understanding of the general background of this application, and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Utility Model Content

[0005] In view of this, the purpose of this application is to provide a key switch assembly and a keyboard to solve at least one technical problem existing in the existing key switch structure.

[0006] To achieve the above objectives, this application provides a key shaft assembly, comprising:

[0007] Key shell;

[0008] The shaft is partially inserted into the key housing and slides in cooperation with the key housing;

[0009] An elastic element, disposed within the key housing, is connected to both the shaft core and the key housing; and...

[0010] An optical flow sensor is covered by the key housing and is located on one side of the shaft core and spaced apart from the shaft core;

[0011] The shaft core can be driven to move in a preset direction, and the elastic element stores elastic potential energy; the elastic element can release the elastic potential energy to drive the shaft core to move in the opposite direction to the preset direction.

[0012] The optical flow sensor can emit laser light onto the surface of the shaft core and receive the laser signal reflected from the surface of the shaft core to realize the axial position detection of the shaft core.

[0013] In some embodiments, the preset direction is the direction in which the shaft is driven to move closer to the optical flow sensor; the side surface of the shaft facing the optical flow sensor is set as an inclined plane; the optical flow sensor is used to emit laser light towards the inclined plane.

[0014] In some embodiments, the optical flow sensor includes a laser emitter and an image sensor; the laser emitter is used to emit laser light toward the inclined plane; the image sensor is used to receive laser signals reflected from the inclined plane; the laser emitter and the image sensor are disposed on opposite sides of the normal to the inclined plane.

[0015] In some embodiments, the optical flow sensor further includes a processing unit; the processing unit is configured to obtain brightness information and / or displacement information of the laser signal received by the image sensor, and then detect the axial position of the shaft core based on the brightness information and / or displacement information of the laser signal.

[0016] In some embodiments, the laser emitter is positioned as close as possible to the inclined plane.

[0017] In some embodiments, the shaft has an initial position and a limit position, and is capable of moving back and forth between the initial position and the limit position; wherein when the shaft moves to the limit position in the preset direction, the laser signal is located between the laser emitter and the image sensor; at the limit position, the shaft is not in contact with the optical flow sensor.

[0018] In some embodiments, the key housing includes a split shaft cover and a base; the shaft core is sequentially inserted into the shaft cover and the base, and slides in cooperation with the shaft cover and the base; the elastic element is at least partially disposed inside the shaft cover, one end of the elastic element is connected to the base, and the other end of the elastic element is connected to the shaft core; the optical flow sensor is disposed inside the base.

[0019] In some embodiments, the elastic element is a spring, which is sleeved on the shaft and confined between the base and the shaft.

[0020] In some embodiments, the shaft core is provided with a flange, one end of the spring is connected to the base and / or the shaft cover, and the other end of the spring is connected to the flange.

[0021] To achieve the above objectives, this application also provides a keyboard, including a circuit board and a key switch assembly as described in any one of the claims; the key shell and optical flow sensor of the key switch assembly are both fixed on the circuit board; the keyboard is configured to trigger a key signal when the axial position of the switch core reaches a trigger condition.

[0022] As described above, this application provides a key switch assembly and keyboard employing optical flow sensing technology. Its core lies in using an optical flow sensor to collect laser signals reflected from the surface of the switch core in real time to detect the axial position of the switch core. When the axial position of the switch core reaches the trigger condition, a key signal is triggered. This design offers several advantages: firstly, the absence of physical contact avoids wear and extends service life; secondly, it is less susceptible to external magnetic fields and temperature changes, making it particularly suitable for environments with magnetic interference and high temperatures, thus improving reliability and broadening its application range; thirdly, it offers better sensitivity, even surpassing Hall effect keys, with fast response speed and good consistency, thereby improving overall performance. It also boasts advantages such as small size, low cost, and flexible installation location. Attached Figure Description

[0023] Those skilled in the art will understand that the accompanying drawings are provided to better understand this application and do not constitute any limitation on the scope of this application.

[0024] Figure 1A schematic diagram of a key shaft assembly according to an embodiment of this application is shown. The key shaft assembly is mounted on a circuit board. A three-dimensional rectangular coordinate system XYZ is shown in the upper right corner of the figure.

[0025] Figure 2 A schematic diagram of the structure of an optical flow sensor according to an embodiment of this application is shown;

[0026] Figure 3 The image information detected by the optical flow sensor receiving the reflected laser signal according to an embodiment of this application is shown. The image information includes brightness information and displacement information. The brightness and displacement data are normalized results. In the figure, the red line represents the image displacement in the X direction, the blue line represents the image displacement in the Y direction, and the green line represents the image brightness. The horizontal axis represents time (dimensionless), and the vertical axis represents the displacement in the X and Y directions and the image brightness (dimensionless).

[0027] Figures 4A-4C A schematic diagram of the process of pressing and moving the shaft core according to an embodiment of this application is shown. In the figure, arrow A indicates the downward direction and arrow B indicates the moving direction of the reflected laser.

[0028] Figure 5 A schematic diagram showing the key travel and target position according to an embodiment of this application is provided.

[0029] Explanation of reference numerals in the attached figures:

[0030] 10-Key shaft assembly, 1-Key housing, 11-Base, 12-Shaft cover, 13-Mounting surface, 2-Shaft core, 21-Bevel, 22-Closest point, 23-Flange, 3-Elastic element, 4-Optical flow sensor, 41-Laser emitter, 42-Image sensor, 20-Circuit board. Detailed Implementation

[0031] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. This application can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of this application. Therefore, the illustrations only show components related to this application and are not drawn according to the actual number, shape, and size of components in the actual implementation. In the actual implementation, the type, quantity, and proportion of each component can be arbitrarily changed, and the component layout may also be more complex.

[0032] Furthermore, while each embodiment described below possesses one or more technical features, this does not imply that users of this application must simultaneously implement all technical features in any embodiment, or can only separately implement some or all technical features in different embodiments. In other words, where implementation is possible, those skilled in the art can selectively implement some or all of the technical features in any embodiment, or selectively implement a combination of some or all of the technical features in multiple embodiments, based on the disclosure of this application and depending on design specifications or implementation requirements, thereby increasing the flexibility in implementing this application.

[0033] As used herein, the singular forms “a,” “an,” and “the” include plural objects, and the plural form “multiple” includes two or more objects, unless otherwise expressly indicated. As used herein, the term “or” is generally used to include the meaning of “and / or,” unless otherwise expressly indicated, and the terms “installed,” “connected,” and “linked” should be interpreted broadly, for example, as a fixed connection, a detachable connection, or an integral connection. Connections can be mechanical or electrical. Connections can be direct or indirect through an intermediate medium, and can be internal communication between two elements or an interaction between two elements. Relational terms such as “first,” “second,” etc., are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations, nor do they indicate or imply relative importance or implicitly specify the number of indicated technical features. It should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0034] To make the objectives, advantages, and features of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of this application.

[0035] Typically, magnetic switch keyboards use Hall effect sensors to detect changes in the magnetic field caused by the movement of magnets inside the switch to trigger key presses. Although magnetic switch keyboards have many advantages, they still have some problems that ultimately affect the overall performance and user experience of the keyboard.

[0036] Based on this, the present application provides a key switch assembly and a keyboard that improves overall performance and enhances user experience while retaining the advantages of the original magnetic switch, and also simplifies the structure, reduces the size, and lowers the cost.

[0037] Figure 1 A schematic diagram of the key shaft assembly 10 provided in an embodiment of this application is shown. Figure 1 As shown, the key shaft assembly 10 includes: a key housing 1, a shaft core 2, an elastic element 3, and an optical flow sensor 4.

[0038] The shaft core 2 is partially inserted into the key housing 1 and slides within it. When driven, the shaft core 2 can move in a preset direction (e.g., the direction of gravity corresponding to the Z-axis), which corresponds to the axial direction of the shaft core 2. Generally, the preset direction is vertically downward. However, this application does not exclude the possibility of other preset directions; that is, the direction of movement of the shaft core 2 can be adjusted according to the installation direction of the key shaft assembly 10.

[0039] The elastic element 3 is disposed inside the key housing 1 and is connected to both the shaft core 2 and the key housing 1. It should be noted that the "connection" between the elastic element 3 and the shaft core 2 and the key housing 1 can include contact. With this configuration, when the shaft core 2 is driven to move in the preset direction, the elastic element 3 can store elastic potential energy; conversely, the elastic element 3 releases elastic potential energy to drive the shaft core 2 to move in the opposite direction to the preset direction.

[0040] The optical flow sensor 4 is covered by the key housing 1 and is located on one side of the spindle core 2, spaced apart from it. This spaced-apart arrangement means that the optical flow sensor 4 does not contact the spindle core 2. With this configuration, the optical flow sensor 4 can directly emit laser light onto the surface of the spindle core 2 and receive the laser signal reflected from the surface of the spindle core 2 to detect the axial position of the spindle core 2. The axial position of the spindle core 2 can be a stationary position or a position during movement. Only after detecting the axial position of the spindle core 2 can it be determined whether a key press signal has been triggered. Note that the optical flow sensor 4 is separate from the key housing 1 and is directly mounted on the circuit board 20; no additional data pins are needed to transmit the detection data from the optical flow sensor 4 to the circuit board 20.

[0041] Those skilled in the art will understand that the optical flow sensor 4 is a device that measures the motion of an object relative to its surrounding environment. It can identify moving objects and detect their distance, direction, and speed. Therefore, by replacing the Hall sensor with the optical flow sensor 4, the change in light signal caused by the movement of the shaft core 2 is detected to trigger key presses, improving keyboard performance and user experience. Furthermore, the function and implementation of the optical flow sensor 4 are readily understood by those skilled in the art; therefore, this application will not elaborate further.

[0042] Meanwhile, this application also provides a keyboard, including a circuit board 20 and a key switch assembly 10; wherein the key housing 1 and the optical flow sensor 4 of the key switch assembly 10 are both fixed on the circuit board 20, thus the installation position is flexible and the use is more convenient. In addition, the keyboard is configured to trigger a key signal when the axial position of the switch core 2 reaches the trigger condition.

[0043] It should be understood that the triggering conditions described above are pre-set target positions; when a button is pressed and reaches the target position, a button signal is triggered; otherwise, a button signal is not triggered. The target position can be adjusted and is not unique, to meet the triggering requirements of different application scenarios. For example, in situations requiring fast response, the button travel can be reduced, and the target position should be set smaller to improve response speed.

[0044] With this configuration, each key in the keyboard can use the key axis assembly 10 provided in the embodiments of this application. Not only is the key structure simple, there is no physical contact wear and the life is long, but it is also not easily affected by external magnetic fields and temperature changes. At the same time, it has good consistency, is programmable, and has better sensitivity, even surpassing Hall effect keys. Moreover, it has relatively low cost, small size, flexible installation position, and can also be used in environments with magnetic field interference and high temperature environments, making it more widely applicable and easier to use.

[0045] In some embodiments, the preset direction is the direction in which the shaft core 2 is driven to move closer to the optical flow sensor 4. With this configuration, the movement of the shaft core 2 in the preset direction can be converted into changes in the image (i.e., laser signal) perpendicular to the preset direction (e.g., changes in brightness and / or position) by an optical flow sensor 4. This method is simple in structure and convenient for detection.

[0046] Furthermore, the surface of the shaft core 2 facing the optical flow sensor 4 is set as an inclined plane 21, and the tilt angle of the inclined plane 21 can be adjusted as needed. In this case, the optical flow sensor 4 emits laser light directly into the inclined plane 21 of the shaft core 2. With this configuration, the movement of the shaft core 2 in a preset direction is directly converted into a change in the image perpendicular to the preset direction through the inclined plane 21, realizing a linear conversion of axial movement. However, in other cases, the surface of the shaft core 2 facing the optical flow sensor 4 can be set as a plane to achieve essentially the same or similar effect.

[0047] Those skilled in the art should know that the tilt angle of the inclined plane 21 is related to the divergence angle of the laser emitter. Therefore, the tilt angle of the inclined plane 21 can be set according to the divergence angle of the laser emitter. This application does not limit this, as long as it ensures that the laser projected onto the inclined plane 21 can still be captured by the optical flow sensor 4 after being reflected.

[0048] Figure 2 A schematic diagram of the structure of the optical flow sensor 4 provided in an embodiment of this application is shown. Figure 2 As shown, in some embodiments, the optical flow sensor 4 includes a laser emitter 41 and an image sensor 42. The laser emitter 41 emits laser light towards the surface of the shaft core 2 (e.g., inclined plane 21). The image sensor 42 receives the laser signal reflected from the surface of the shaft core 2 (e.g., inclined plane 21). Further, the nearest point (e.g., the lowest point) 22 of the inclined plane 21 is located to one side of the laser emitter 41. For example, in this embodiment, the laser generator 41 is located between the image sensor 42 and the orthographic projection of the lowest point (22) of the inclined plane 21 onto the optical flow sensor 4.

[0049] Furthermore, the optical flow sensor 4 may also include a processing unit, which is used to detect the axial position of the core 2 based on the laser signal received by the image sensor 42.

[0050] There are multiple ways to detect the axial position of the shaft core 2, and at least one can be selected for execution.

[0051] As an example, the processing unit detects the axial position of the core 2 based on the brightness information of the laser signal.

[0052] As an example, the processing unit detects the axial position of the shaft core 2 based on the displacement information of the laser signal.

[0053] In other examples, the processing unit detects the axial position of the core 2 based on the brightness and displacement information of the laser signal.

[0054] Figure 3The image information detected by the optical flow sensor 4 based on the reflected laser signal is shown. This image information includes brightness and displacement information. Both brightness and displacement data are normalized results. For ease of understanding, different colored lines represent brightness and displacement. In the figure, the red line represents image displacement in the X direction, the blue line represents image displacement in the Y direction, and the green line represents image brightness. Figure 3 As shown, in some embodiments, the optical flow sensor 4 receives the laser signal reflected back from the surface of the shaft core 2, and obtains the displacement and brightness information of the image corresponding to the laser signal in the X and Y directions. Then, the axial position of the shaft core 2 can be calculated based on the brightness information and displacement information.

[0055] In some embodiments, the processing unit of the optical flow sensor 4 can determine whether to trigger a button signal based on the detected axial position of the shaft core 2. Specifically, the button signal is triggered when the axial position of the shaft core 2 is the target position.

[0056] In some other embodiments, the optical flow sensor 4 does not have a processing unit. Instead, the axial position of the shaft core 2 is detected directly by an external device based on the laser signal received by the image sensor 42. For example, the axial position of the shaft core 2 is detected based on the brightness information and / or displacement information of the laser signal, and a button signal is determined based on the detected axial position of the shaft core 2.

[0057] Furthermore, obtaining the axial position of the shaft core 2 based on the brightness and / or displacement information of the laser signal is easily achieved by those skilled in the art based on their knowledge. For example, the commonly used laser triangulation distance measurement is based on the use of laser, imaging and photoelectric detection to achieve non-contact measurement and calculate the distance to the object through optical geometry principles, which can achieve high-precision measurement over short distances. In short, it can be achieved based on existing technologies such as computer vision and image processing, so its implementation process will not be described in detail.

[0058] Furthermore, the inclined surface 21 of the shaft core 2 has the ability to reflect laser light, such as by being made of a material that can reflect laser light or by applying a coating to the inclined surface 21 to increase reflectivity. In practice, the laser emitted by the laser emitter 41 is projected onto the inclined surface 21, forming a laser speckle (interference pattern), which is then reflected to the optical flow sensor 4, obtaining a laser spot with a certain size and shape. The axial position of the shaft core 2 is then obtained based on the brightness and / or displacement of the laser spot. Preferably, the position of the shaft core 2 is calculated based on the brightness change of adjacent frame images (laser spots) and the displacement between adjacent frame images (laser spots), combined with the principle of triangulation.

[0059] It should also be understood that the laser emitter 41 and the image sensor 42 are arranged at intervals; the image sensor 42 is arranged in the direction of the reflection line, and the laser emitter 41 and the image sensor 42 are in the same plane, located on both sides of the normal of the inclined plane 21, ensuring that the incident line of the laser emitter 41, the reflection line and the normal of the inclined plane 21 are in the same plane.

[0060] The laser emitter 41 can be positioned at various distances from the inclined plane 21, as long as the reflected laser signal can be captured by the image sensor 42 during the back-and-forth movement of the shaft core 2.

[0061] In some embodiments, the laser emitter 41 is positioned closest to the inclined plane 21, such as... Figure 1 As shown. Figure 1 In the middle, the position closest to the inclined plane 21 is the position of the nearest point 22 to the inclined plane 21, and the laser emitter 41 is set directly below or slightly offset from the nearest point 22.

[0062] In some other embodiments, the laser emitter 41 is positioned at a distance from the middle of the inclined plane 21, which is any position between the farthest and closest positions from the inclined plane 21.

[0063] The position of the image sensor 42 is adjusted accordingly based on the position of the laser emitter 41.

[0064] As an example, such as Figure 1 As shown, the optical flow sensor 4 is positioned directly below the shaft core 2.

[0065] Furthermore, when the shaft core 2 is not pressed, it is in its initial position, which is the position furthest from the optical flow sensor 4.

[0066] The shaft core 2 also has limit positions when moving in a preset direction. The shaft core 2 can move back and forth between the initial position and the limit position.

[0067] In some embodiments, the extreme positions of the shaft core 2 are defined by a mechanical structure, and / or, in other embodiments, the extreme positions of the shaft core 2 are set by a program.

[0068] In some embodiments, when the elastic element 3 is in the extreme state of compression, that is, corresponding to the extreme position of the shaft core 2.

[0069] In some embodiments, a blocking structure is provided inside the key housing 1; when the spindle 2 moves in a preset direction to the blocking structure, it reaches its limit position.

[0070] As an example, such as Figure 1 As shown, the key housing 1 has a mounting surface 13 inside, which is used to install and fix the elastic element 3 and to limit the shaft core 2.

[0071] As an example, the shaft core 2 is provided with a flange 23; when the flange 23 contacts the mounting surface 13, the shaft core 2 no longer moves downward and stops at the limit position.

[0072] Furthermore, when the shaft core 2 moves to its limit position in the preset direction, the reflected laser signal is located between the laser emitter 41 and the image sensor 42. In this case, the image sensor 42 receives no reflected light at all, or the image sensor 42 receives a small amount of reflected light, resulting in the lowest image brightness.

[0073] Furthermore, when the shaft core 2 moves to its limit position in the preset direction, the shaft core 2 and the optical flow sensor 4 do not come into contact. Here, "not in contact" can mean being infinitely close or separated by a certain distance.

[0074] It should be understood that the target position and the extreme position mentioned above may be the same or different, but in general, the target position does not exceed the extreme position.

[0075] The key housing 1 can be a split design or a one-piece design. In this embodiment, the key housing 1 includes a split base 11 and a shaft cover 12, which facilitates the installation of the elastic element 3.

[0076] The shaft cover 12 is mounted on the base 11 and fixed in a suitable manner. Specifically, the shaft cover 12 can be provided on the mounting surface 13 of the base 11. Furthermore, the base 11 is fixed to the circuit board 20, which can be achieved through various means. As an example, the base 11 is fixed to the circuit board 20 by at least two locating posts (not shown).

[0077] Furthermore, the shaft core 2 is sequentially inserted into the shaft cover 12 and the base 11, and slides in cooperation with the shaft cover 12 and the base 11. "Sliding cooperation" means clearance cooperation. Understandably, both the shaft cover 12 and the base 11 are provided with guide holes for the shaft core 2 to be inserted, and the guide holes can also limit the movement direction of the shaft core 2 to prevent the shaft core 2 from shaking when it moves.

[0078] Optionally, the key switch assembly 10 also includes a keycap (not shown) that is directly fitted onto the end of the switch core 2 that extends out of the switch cover 12.

[0079] In some embodiments, the elastic element 3 is entirely disposed within the shaft cover 12, with one end of the elastic element 3 connected to the base 11 (e.g., mounting surface 13) and the other end connected to the shaft core 2 (e.g., flange 23). In other embodiments, the elastic element 3 may be partially disposed within the shaft cover 12 and partially disposed within the base 11. In other embodiments, one end of the elastic element 3 may be connected to the shaft cover 12, or one end of the elastic element 3 may be connected to both the shaft cover 12 and the base 11. The flange 23 may be annular or non-annular, and this application is not limited in this regard.

[0080] In some embodiments, the elastic element 3 is a single element, directly sleeved on the shaft core 2 and confined between the base 11 and the shaft core 2. As an example, the elastic element 3 is confined between the mounting surface 13 of the base 11 and the flange 23 of the shaft core 2. Of course, the elastic element 3 can also be confined in other ways besides the flange 23, and this application is not limited to this.

[0081] In other embodiments, there are multiple elastic elements 3, specifically, at least two elastic elements 3 are evenly distributed circumferentially around the shaft core 2, and each elastic element 3 is located between the base 11 and the shaft core 2. For example, one end of each elastic element 3 is connected to the mounting surface 13 of the base 11, and the other end is connected to (including abutting against) the flange 23.

[0082] The elastic element 3 can be various elastic structures, including but not limited to a spring. As an example, the elastic element 3 is a spring, which is sleeved on the shaft core 2 and confined between the mounting surface 13 of the base 11 and the flange 23 of the shaft core 2.

[0083] Furthermore, the optical flow sensor 4 is disposed within the base 11 and is directly or indirectly fixed to the circuit board 20. In this embodiment, the optical flow sensor 4 is directly fixed to the circuit board 20. The optical flow sensor 4 is electrically connected to the circuit board 20, so that the data detected by the optical flow sensor 4 is output through the circuit board 20, thereby triggering the button signal.

[0084] Figures 4A-4C A schematic diagram of the process of pressing and moving the shaft core 2 according to an embodiment of this application is shown. In the figure, arrow A indicates the downward direction and arrow B indicates the movement direction of the reflected laser.

[0085] The following is combined Figures 4A to 4C The working principle of the key shaft assembly 10 provided in the embodiments of this application will be illustrated by way of example.

[0086] In one exemplary embodiment, the key shaft assembly 10 is used as follows:

[0087] (1) When the key shaft assembly 10 is not pressed, the spring is in the most relaxed state, and the inclined surface 21 of the shaft core 2 is farthest from the optical flow sensor 4. At this time, the image brightness obtained by the optical flow sensor 4 is relatively dark.

[0088] (2) such as Figure 4A and Figure 4B After the key shaft assembly 10 is pressed, the spring is compressed, and the inclined surface 21 of the shaft core 2 gradually approaches the optical flow sensor 4, as shown by arrow A. At the same time, the laser spot begins to move towards the laser emitter 41, as shown by arrow B. At this time, the image displacement obtained by the optical flow sensor 4 is positive (see...). Figure 3 The image brightness gradually increases, and after reaching its maximum value, the brightness begins to decrease.

[0089] (3) such as Figure 4C When the key axis assembly 10 reaches its limit position, it triggers the key signal. At this time, the spring is compressed to its limit, the inclined surface 21 of the axis core 2 is closest to the optical flow sensor 4, the laser spot is reflected between the laser emitter 41 and the image sensor 42, there is no image displacement, and the image brightness is at its lowest value.

[0090] (4) Release the key shaft assembly 10, the spring returns, and the inclined surface 21 of the drive shaft core 2 gradually moves away from the optical flow sensor 4. The laser spot begins to move away from the laser emitter 41. At this time, the image displacement of the optical flow sensor 4 is negative (see Figure 3 The image brightness first increases and then decreases, eventually returning to the state before it was pressed.

[0091] The above should be understood as follows: when shaft 2 is pressed, starting from the initial position, sequentially from... Figure 4A Position moved down Figure 4C Position, conversely, after release, shaft core 2 sequentially from Figure 4C Position bounced to Figure 4A The position eventually returns to the initial position.

[0092] Figure 5 A schematic diagram of the key travel and target position according to an embodiment of this application is shown. As shown, the travel distance of the shaft core 2 from the initial position to the target position (i.e., the trigger position) is d. As an example, d is less than or equal to 1 mm. It can be understood that the simulated optical axis based on the optical flow sensor 4 can adjust the trigger position and the travel length of the shaft core 2 at any time, and can complete a short press and release action within a very short travel distance, thereby realizing rapid key triggering.

[0093] In summary, this application provides a key switch assembly 10, which can be applied to keyboards in electronic devices such as computers. The key switch assembly 10 itself can obtain the movement position of the key through the optical flow sensor 4, and output the position of the key as an electrical signal (such as voltage) to trigger the key. The overall structure of this design is simple, not easily affected by magnetic field interference and temperature, and has good consistency, stability and reliability, making it particularly suitable for high-frequency input scenarios (such as gaming keyboards).

[0094] While this application discloses the above, it is not limited thereto. Those skilled in the art can make various modifications and variations to this application without departing from its spirit and scope. Therefore, this application also intends to include any modifications and variations that fall within the scope of this application's specification and its equivalents.

Claims

1. A key shaft assembly, characterized in that, include: Key shell; The shaft is partially inserted into the key housing and slides in cooperation with the key housing; An elastic element is disposed inside the key housing and is connected to both the shaft core and the key housing. as well as, An optical flow sensor is covered by the key housing and is located on one side of the shaft core and spaced apart from the shaft core; The shaft core can be driven to move in a preset direction, and the elastic element stores elastic potential energy; the elastic element can release the elastic potential energy to drive the shaft core to move in the opposite direction to the preset direction. The optical flow sensor can emit laser light onto the surface of the shaft core and receive the laser signal reflected from the surface of the shaft core to realize the axial position detection of the shaft core.

2. The key shaft assembly according to claim 1, characterized in that, The preset direction is the direction in which the shaft is driven to move closer to the optical flow sensor; the side surface of the shaft facing the optical flow sensor is set as an inclined plane; the optical flow sensor is used to emit laser light towards the inclined plane.

3. The key shaft assembly according to claim 2, characterized in that, The optical flow sensor includes a laser emitter and an image sensor; the laser emitter is used to emit laser light into the inclined plane; the image sensor is used to receive the laser signal reflected by the inclined plane; the laser emitter and the image sensor are disposed on opposite sides of the normal of the inclined plane.

4. The key shaft assembly according to claim 3, characterized in that, The optical flow sensor further includes a processing unit; the processing unit is used to obtain the brightness information and / or displacement information of the laser signal received by the image sensor, and then detect the axial position of the shaft core based on the brightness information and / or displacement information of the laser signal.

5. The key shaft assembly according to claim 3, characterized in that, The laser emitter is positioned as close as possible to the inclined plane.

6. The key shaft assembly according to claim 3, characterized in that, The shaft has an initial position and a limit position, and is capable of moving back and forth between the initial position and the limit position; wherein when the shaft moves to the limit position in the preset direction, the laser signal is located between the laser emitter and the image sensor; at the limit position, the shaft is not in contact with the optical flow sensor.

7. The key shaft assembly according to claim 1 or 2, characterized in that, The key housing includes a split shaft cover and a base; the shaft core is inserted into the shaft cover and the base in sequence and slides in cooperation with the shaft cover and the base; the elastic element is at least partially disposed in the shaft cover, one end of the elastic element is connected to the base, and the other end of the elastic element is connected to the shaft core; the optical flow sensor is disposed in the base.

8. The key shaft assembly according to claim 7, characterized in that, The elastic element is a spring, which is sleeved on the shaft core and confined between the base and the shaft core.

9. The key shaft assembly according to claim 8, characterized in that, The shaft core is provided with a flange, one end of the spring is connected to the base and / or the shaft cover, and the other end of the spring is connected to the flange.

10. A keyboard, characterized in that, The keyboard includes a circuit board and a key axis assembly as described in any one of claims 1-9; the key housing and optical flow sensor of the key axis assembly are both fixed on the circuit board; the keyboard is configured to trigger a key signal when the axial position of the key axis reaches a trigger condition.

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