Key stroke detection scheme applied to key shake resistance of magnetic axis keyboard

Abstract

The invention provides a key stroke detection scheme applied to key shaking resistance of a magnetic axis keyboard, the scheme adopts a plurality of magnetic sensor chip sets to detect the moving position of a magnet at the same time, the magnet is pressed along with the key, when the key is pressed to the bottom, the hand usually shakes, and the shaking of the bottom changes the intensity of a magnetic field, so that the key stroke is detected. However, the detection precision required by the current magnetic axis keyboard product is generally less than 0.1 mm, that is, the small magnetic field change needs to be responded, and the magnetic field change caused by bottom shaking has a great probability to mistakenly consider that the key is released, so that the key mistakenly sends a code. According to the invention, the plurality of magnetic sensor chip sets are adopted to detect the magnetic field change at the same time, whether the key is shaken instead of being released can be judged according to the signal relative change values of the plurality of magnetic sensors, wrong code sending is avoided, a bottom dead zone is eliminated, and the user experience can be greatly improved.

Description

Technical Field

[0001] The invention patent relates to a key travel detection scheme for magnetic axis keyboards to resist key shaking. Background Art

[0002] The current magnetic axis keyboard market is highly competitive, and the requirements for key travel detection accuracy are getting higher and higher, which greatly increases the design difficulty. When the key is pressed to the bottom, the human hand usually shakes, and the shaking of the bottom will change the strength of the magnetic field. The current magnetic axis keyboard products require a detection accuracy of usually less than 0.1mm, that is, even very small changes in the magnetic field need to be responded to. There is a high probability that the magnetic field changes caused by the shaking of the bottom will be mistaken for a key release, resulting in the wrong key code. The products on the market currently usually increase the dead zone at the bottom of the key. For example, the bottom of the key does not respond at 0.3mm, that is, the dead zone is used to avoid bottom shaking, affecting the user experience. Summary of the invention

[0003] The present invention uses multiple magnetic sensor chipsets to simultaneously detect magnetic field changes, and can analyze the relative change values ​​of the signals of multiple magnetic sensors, so as to determine whether the key is shaking rather than being released, avoiding mis-sending of codes, and no dead zone is added to the bottom of the key, that is, the entire key stroke can respond quickly, thereby greatly improving the user experience.

[0004] The embodiment of the present invention is a key stroke detection scheme for a magnetic axis keyboard to resist key shaking, and has the following characteristics: (1) Multiple magnetic sensor chipsets are used to simultaneously detect the moving position of a magnet. The magnet is placed above the magnetic sensor chipset. As the key is pressed, the distance between the magnet and the magnetic sensor changes accordingly. (2) The magnet and magnetic sensor chipset are usually center-aligned, but center alignment is not always necessary; (3) The multiple magnetic sensor chipsets may be composed of 2, 3, 4 or more magnetic sensors, and the multiple magnetic sensor chipsets may be packaged separately or packaged together in one package; (4) There can be one or more communication lines between the magnetic sensor chipset and the MCU controller, and the transmitted signal can be a digital signal or an analog signal, or partly a digital signal and partly an analog signal; (5) The magnet is placed in the button and moves up and down as the button is pressed, thereby changing the distance between the magnet and the magnetic sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] The above and other features, properties and advantages of the present invention will become more apparent through the following description of the embodiments in conjunction with the accompanying drawings, in which the same reference numerals always represent the same features, wherein: Figure 1 A system block diagram showing a key stroke detection scheme for a magnetic axis keyboard to resist key shaking according to the present invention is shown; Figure 2 It shows a schematic diagram of a traditional magnetic axis button shaking when pressed to the bottom; Figure 3 A schematic diagram showing the shaking of the magnetic axis button of the present invention when it is pressed to the bottom; 100 —— A key stroke detection scheme for a magnetic axis keyboard to resist key shaking according to the present invention; 101 —— MCU controller; 102 - magnet, located in the key; 103 —— Multiple magnetic sensor chipsets; 200 —— Diagram of the traditional magnetic axis button shaking when pressed to the bottom; 201 —— Normal button is pressed to the bottom magnet position; 202 —— Diagram of the key being pushed to the bottom and the magnet shaking to the left; 203 —— Magnetic sensor 0; 300 —— Schematic diagram of the magnetic axis button of the present invention being shaken when pressed to the bottom; 301 —— Normal button is pressed to the bottom magnet position; 302 —— Diagram of the button being pushed to the bottom and the magnet shaking to the left; 303 —— Magnetic sensor 1; 304 —— Magnetic sensor 2; DETAILED DESCRIPTION

[0006] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0007] Embodiments of the present invention will now be described with reference to the accompanying drawings in detail. Reference will now be made in detail to preferred embodiments of the present invention, examples of which are shown in the accompanying drawings. Wherever possible, the same reference numerals will be used in all drawings to represent the same or similar parts. In addition, although the terms used in the present invention are selected from well-known and commonly used terms, some of the terms mentioned in the specification of the present invention may be selected by the applicant at his or her discretion, and their detailed meanings are explained in the relevant parts of the description herein. In addition, it is required to understand the present invention not only by the actual terms used, but also by the meaning implied by each term.

[0008] like Figure 1As shown, the present invention uses multiple magnetic sensor chipsets to simultaneously detect the moving position of a magnet, and the magnet approaches the magnetic sensor as the key is pressed. When the key is pressed to the bottom, the human hand usually shakes, and the shaking of the bottom will change the strength of the magnetic field. The current magnetic axis keyboard products require a detection accuracy of less than 0.1mm, that is, even very small changes in the magnetic field need to be responded to. Due to the change in the magnetic field caused by the shaking of the bottom, there is a high probability that it will be mistaken for a key release, resulting in the key sending a wrong code. The products on the market currently usually use a dead zone to increase the bottom of the key. For example, the bottom of the key does not respond to 0.3mm, that is, the dead zone is used to avoid the wrong code caused by the shaking of the bottom, which affects the user experience.

[0009] Traditional magnetic axis buttons use a single magnetic sensor, such as Figure 2 As shown, for ease of description and understanding, we take the example of magnet 201 facing magnetic sensor 203. Ideally, the key is pressed to the bottom of the magnet position. Figure 2 As shown in 201, the magnet is facing the center of the magnetic sensor. Figure 2 The magnetic field signal detected by the 203 magnetic sensor 0 is the strongest; when a key is shaken, assuming it is shaken to the left, the position of the magnet is as follows Figure 2 As shown in 202, the magnetic field intensity sensed by the magnetic sensor 0 will decrease at this time. This change in magnetic field intensity is reflected in the sensing distance, usually with a deviation of 0.2~0.4mm. The signal change read by the MCU at this time exceeds 0.1mm, and it will be judged as a key release, resulting in a wrong code. Since key shaking is a limitation of the physical structure of the key and cannot be eliminated, in order to avoid the bottom shaking and wrong code sending, the traditional solution can only use the bottom 0.2~0.4mm as the key dead zone and no response, which affects the user experience.

[0010] In order to facilitate the description and understanding of the present invention, we use two magnetic sensor detection schemes to illustrate, such as Figure 3 As shown, ideally the button is pressed to the bottom and the magnet position is as follows Figure 3 As shown in 301, the magnet is facing the center of the two magnetic sensors. Figure 3 303 magnetic sensor 1 and Figure 3 The magnetic field strength sensed by the 304 magnetic sensor 2 is exactly the same. If the MCU controller reads the same signal from the two magnetic sensors, it will determine that there is no shaking. When the button is shaken, assuming it is shaken to the left, the position of the magnet is as follows Figure 3 As shown in 302, at this time, the magnetic field strength sensed by magnetic sensor 1 will increase, and the magnetic field strength sensed by magnetic sensor 2 will decrease. The MCU controller reads the difference in the signals of the two magnetic sensors, and can determine that the key is shaking without sending a code, so there is no need to set a dead zone at the bottom of the key, which can improve the user experience.

[0011] Figure 3The example of the present invention uses two magnetic sensors. This solution can only solve the left-right shaking of the key, but cannot solve the front-back shaking of the key; similarly, even if the two magnetic sensors are placed front and back, this can only solve the front-back shaking of the key, but cannot solve the left-right shaking of the key, that is, the two magnetic sensors can only solve the shaking of the key in a single direction. Due to ergonomics, most of the bottom shaking of the key is mainly front-back shaking, so the use of two magnetic sensors for detection can improve most of the bottom shaking situations.

[0012] Similarly, we can use three magnetic sensors in a triangular layout for detection; we can also use four sensors in a field layout for detection, so that shaking from front to back, left to right can be detected; theoretically, the more sensors there are, the more accurately the shaking direction of the bottom of the key can be detected, and in reality, based on actual application conditions and cost and structural considerations, using four sensors is accurate enough to meet the application of magnetic axis keyboards, solve the dead zone problem at the bottom of the magnetic axis keys, improve user experience, and enhance product competitiveness.

[0013] Although the specific embodiments of the present invention are described above, those skilled in the art should understand that these are only examples, and the protection scope of the present invention is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but these changes and modifications all fall within the protection scope of the present invention.

Claims

1. A key stroke detection scheme for magnetic axis keyboard to resist key shaking, characterized by: The key travel detection scheme for the magnetic axis keyboard to resist key shaking uses multiple magnetic sensor chipsets to simultaneously detect the moving position of a magnet. The magnet is placed above the magnetic sensor chipset. As the key is pressed, the distance between the magnet and the magnetic sensor changes accordingly.

2. The key stroke detection scheme for magnetic axis keyboard against key shaking as claimed in claim 1, characterized in that: The magnet and magnetic sensor chipset are usually center-aligned, but they may not be center-aligned.

3. The key stroke detection scheme for magnetic axis keyboard against key shaking as claimed in claim 1, characterized in that: The plurality of magnetic sensor chipsets may be composed of 2, 3, 4 or more magnetic sensors.

4. The key stroke detection scheme for resisting key shaking of a magnetic axis keyboard as claimed in claim 1, characterized in that: The plurality of magnetic sensor chipsets may be packaged separately or packaged together in one package.

5. The key stroke detection scheme for resisting key shaking of a magnetic axis keyboard as claimed in claim 1, characterized in that: There may be one or more communication lines between the magnetic sensor chipset and the MCU controller, and the transmitted signal may be a digital signal or an analog signal, or partly a digital signal and partly an analog signal.

6. The key stroke detection scheme for resisting key shaking of a magnetic axis keyboard as claimed in claim 1, characterized in that: The magnet is placed in the button and moves up and down as the button is pressed, thereby changing the distance between the magnet and the magnetic sensor.

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