Inductive magnetic levitation keyboard

Abstract

The application discloses an inductive magnetic levitation keyboard, which has a base and a shell with multiple hollow parts, and comprises: a circuit board fixed between the base and the shell, the circuit board comprising multiple induction coils corresponding to multiple keys and a control unit coupled through a circuit; multiple first magnetic bodies arranged in the base and below the multiple induction coils of the circuit board; multiple key shafts arranged above the multiple induction coils of the circuit board, the multiple key shafts being provided with keycaps located in the hollow parts of the shell and constituting the multiple keys, each key shaft being provided with a second magnetic body with the property of conductive metal, and the key shaft being interferingly positioned with the shell through a limiting mechanism, the first magnetic body and the second magnetic body having repulsive force and lifting the key shaft to form a magnetic levitation state, so that the structure of the existing Hall element can be omitted, and the manufacturing cost of the keyboard can be saved.

Description

Technical Field

[0001] This invention relates to an inductive magnetic levitation keyboard, specifically a keyboard that uses the repulsive force between a first magnetic body and a second magnetic body to form linear key travel, and whose pressing force can be adjusted by changing the magnetic flux between the first and second magnetic bodies. Furthermore, the control unit determines whether to generate a trigger signal by sensing whether the inductance value of the second magnetic body in the key shaft is greater than a predetermined threshold, thus eliminating the need for the existing structure that requires a Hall element to sense the magnetic field strength of the magnetic body, thereby saving keyboard manufacturing costs and avoiding additional magnetic interference from the two magnets themselves, which have repulsive or attractive forces, on the Hall element. Background Technology

[0002] Computers and the internet have profoundly impacted modern life, with functions such as word processing, drawing, image processing, audio and video playback, online research, online shopping, and online gaming becoming indispensable both at home and at work. When operating a computer, the keyboard and mouse are crucial input devices. The keyboard, a mature product, operates on the principle that pressing a key causes a mechanism beneath it to sink, deforming an elastic body. A conductive block within the elastic body contacts the circuit board, generating a trigger signal that displays a corresponding character at the cursor position on the computer screen. This is the basic structure and operating principle of a keyboard.

[0003] Please refer to the utility model patent "Keyboard Device" in Taiwan Patent Publication No. M603187. Figure 1 Figure 2 shows a conventional keyboard device 100 comprising multiple key structures 110. Each key structure 110 includes a keycap 111 and a switch 112 disposed below the keycap 111. The keycap 111 connects to the switch 112. The keyboard device 100 is a mechanical keyboard. The switch 112 includes a housing 120, a spindle 130, and a spring 140. The spindle 130 is vertically detachable from the housing 120. The switch 112 further includes a spring 113, which is disposed within the housing 120 and connected between the bottom of the spindle 130 and the bottom of the housing 120. The spring 113 is configured to provide an upward thrust to the spindle 130. This allows the keyboard device to switch between two modes: spring-interference with the spindle 130 and spring-non-interference with the spindle 140, providing two different key feel options for the user to adjust and choose. While the aforementioned conventional keyboard allows for different key feel options, its complex structure and high cost are disadvantages.

[0004] Furthermore, some manufacturers produce mechanical keypads that use two magnets with mutual repulsion or attraction to adjust the key travel and use Hall sensors to detect whether a key is pressed. However, the use of Hall sensors in existing keyboards not only causes additional magnetic interference from the two magnets themselves, but also increases production costs and is not conducive to marketing. These shortcomings of existing keyboards are the problems that this invention aims to improve and solve. Summary of the Invention

[0005] Therefore, in view of the above-mentioned problems and deficiencies, the purpose of this invention is to provide an inductive magnetic levitation keyboard.

[0006] This invention provides an inductive magnetic levitation keyboard, comprising a base and a housing with multiple cutouts, including: a circuit board fixed between the base and the housing, the circuit board including multiple induction coils corresponding to multiple keys and a control unit coupled via circuits; multiple first magnetic bodies disposed in the base and below the multiple induction coils on the circuit board; multiple key shafts disposed on the multiple induction coils on the circuit board, the multiple key shafts having keycaps exposed in the cutouts of the housing and forming the multiple keys, each key shaft having a second magnetic body with conductive metal properties, and the key shaft being positioned by interference with the housing through a limiting mechanism, the first magnetic bodies and the second magnetic bodies having a mutual repulsive force and lifting the key shaft to form a magnetic levitation state.

[0007] As described above, a linear key travel is formed by the mutual repulsion between the first and second magnetic bodies, and the force required to press the key can be adjusted by changing the magnetic flux between the first and second magnetic bodies. Furthermore, whether the inductance value of the second magnetic body in the key shaft sensed by the induction coil is greater than a predetermined threshold determines whether the control unit generates a trigger signal. This eliminates the need for the existing structure that requires a Hall element to sense the magnetic field strength of the magnetic body, thereby saving keyboard manufacturing costs and avoiding additional magnetic interference from the two magnets themselves, which have mutual repulsion or attraction.

[0008] The first magnetic body of the present invention is aligned with or misaligned with the induction coil.

[0009] The first magnetic body of the present invention is a permanent magnet made of neodymium iron boron material or an electromagnet; while the second magnetic body is a permanent magnet made of neodymium iron boron material.

[0010] The induction coil of the present invention has a circular spiral or a rectangular spiral structure.

[0011] When the second magnetic body of the present invention approaches the magnetic field of the induction coil, it can induce eddy currents inside, and the eddy currents cause the second magnetic body to generate a magnetic field opposite to that of the induction coil, thereby changing the inductance value of the induction coil. Attached Figure Description

[0012] Figure 1 This is a side cross-sectional view and magnetic field line diagram of the inductive magnetic levitation keyboard of the present invention.

[0013] Figure 2A This is a schematic diagram of the sensing between the induction coil and the second magnetic body of the present invention.

[0014] Figure 2B This is a schematic diagram of the sensing height of the induction coil of the present invention.

[0015] Figure 2C This is a schematic diagram of the sensing height of another induction coil of the present invention.

[0016] Figure 3 This is a line graph showing the pressing stroke and the level of sensing inductance value of the inductive magnetic levitation keyboard of the present invention.

[0017] Figure 4 This is a line graph showing the pressing displacement and the level of sensing inductance value of the inductive magnetic levitation keyboard of the present invention.

[0018] Figure 5 This is a schematic diagram of the circuit board layout of the present invention.

[0019] Figure 6 This is a side cross-sectional view and magnetic field line diagram of another embodiment of the inductive magnetic levitation keyboard of the present invention.

[0020] Figure 7 This is a side cross-sectional view of another embodiment of the inductive magnetic levitation keyboard of the present invention.

[0021] Explanation of reference numerals in the attached diagram: 1-Circuit board; 11-Induction coil; 111-Magnetic field; 12-Circuit; 2-First magnetic body; 3-Button; 31-Key shaft; 32-Key base; 4-Second magnetic body; 41-Eddy current; h-Magnetic field height; Dout1-Circular diameter; Dout2-Length of the short side of the rectangle. Detailed Implementation

[0022] To achieve the above objectives and effects, the technical means and structure adopted by the present invention are described in detail below with reference to the preferred embodiments of the present invention, so as to facilitate a complete understanding.

[0023] Please see Figures 1-2C , Figure 5The figures show a side cross-section and magnetic field diagram of the inductive magnetic levitation keyboard of the present invention, a sensing diagram of the induction coil and the second magnetic body, a sensing height diagram of the induction coil, a sensing height diagram of the other induction coil, and a layout diagram of the circuit board. As can be clearly seen from the figures, the inductive magnetic levitation keyboard of the present invention mainly includes a circuit board 1, a first magnetic body 2, keys 3, and a second magnetic body. The inductive magnetic levitation keyboard includes a pre-set base (not shown) located below and a pre-set outer shell (not shown) with multiple cutouts attached to the upper part. The keyboard base and outer shell used in this invention are similar to those in known publication number M603187 or other known patents, therefore, no further drawings or explanations are provided. The main components and features of the inductive magnetic levitation keyboard are detailed below:

[0024] The circuit board 1 is fixed between the preset base and the preset housing. The circuit board 1 includes multiple induction coils 11 corresponding to multiple buttons 3, and the multiple induction coils 11 are coupled to a preset control unit (not shown in the figure, which may be a microcontroller unit (MCU) or processor) through a line 12.

[0025] The plurality of first magnetic bodies 2 are disposed in the preset base and below the plurality of induction coils 11 of the circuit board 1.

[0026] The plurality of key shafts 31 are disposed on the plurality of induction coils 11 of the circuit board 1. The plurality of key shafts are provided with keycaps exposed in the hollowed-out part of the preset housing and constitute the plurality of buttons 3. Each key shaft 31 is provided with a second magnetic body 4 having conductive metal properties. The key shaft 31 is positioned by interference with the preset housing through a preset limiting mechanism (not shown in the figure, for example: a stop block). The first magnetic body 2 and the second magnetic body 4 have a mutual repulsive force and lift the key shaft 31 to form a magnetic levitation state. When each key shaft 31 is in the upper position and the inductance value of the second magnetic body 4 sensed by the induction coil 11 is less than a predetermined threshold, the preset control unit coupled to the induction coil 11 will not generate a trigger signal. When each key shaft 31 moves downward toward the induction coil 11 and the inductance value of the second magnetic body 4 sensed is greater than the predetermined threshold, the preset control unit generates a trigger signal.

[0027] A key seat 32 is further installed on the bottom side of the key shaft 31, and the second magnetic body 4 is embedded and fixed between the key shaft 31 and the key seat 32. The assembly structure of the key shaft 31 and the key seat 32 forms a magnetic levitation state through the mutual repulsion between the first magnetic body 2 and the second magnetic body 4.

[0028] like Figure 2A As shown, when the second magnetic body 4 approaches the magnetic field 111 of the induction coil 11, it can induce eddy current 41 inside, and the eddy current 41 causes the second magnetic body 4 to generate a magnetic field opposite to that of the induction coil 11, and changes the inductance value of the induction coil 11.

[0029] like Figure 2B As shown, when the induction coil 11 has a circular spiral structure, it can generate a magnetic field with a height h = Dout1 (circular diameter) / 2; please refer to Figure 2C As shown, when the induction coil 11 has a rectangular spiral structure, it can generate a magnetic field height h = Dout2 (length of the shorter side of the rectangle) / 2. The shape of the induction coil 11 is not limited to a circle or a rectangle, and can also be other geometric shapes (e.g., triangle, square, rhombus, pentagon, hexagon, octagon, or star). The aforementioned magnetic field height h refers to the height of the magnetic lines of force generated on the upper and lower surfaces of the induction coil 11. By calculating the magnetic field height h of the induction coil 11, the spacing between the induction coil 11 and the first magnetic body 2 and the second magnetic body 4, the pressing stroke, and the level of sensing inductance can be effectively adjusted.

[0030] Please see Figure 3 The diagram shows the press travel and sensing inductance level of the inductive magnetic levitation keyboard of the present invention. The lower left dashed line of the diagram indicates that when the press travel range of the X-axis is approximately 0 to 0.5 mm, the sensing inductance level of the Y-axis induction coil 11 is approximately 0 to 35. A sensing inductance level greater than 35 can be considered a predetermined threshold. When the press travel of the key switch 31 is less than 0.5 mm and the sensing inductance level is less than 35, the preset control unit coupled to the induction coil 11 will not generate a trigger signal. In addition, the upper right dashed line of the diagram indicates that when the press travel is approximately 3 to 3.5 mm, the sensing inductance level of the induction coil 11 is approximately 200 to 255. This section is discarded because the sensing inductance value is too large and the press travel of the key switch 31 is too long and easily exceeds the position of the circuit board 1. Therefore, the available travel of the pressing key shaft 31 downwards towards the induction coil 11 is approximately 0.5 to 3 mm, and the induction coil 11 can sense inductance values ​​ranging from approximately 35 to 200, thereby triggering a preset control unit to generate a trigger signal.

[0031] Please see Figure 4 The figure shown is a line graph of the pressing displacement and the level of sensing inductance value of the inductive magnetic levitation keyboard of the present invention. This line graph is related to... Figure 3 The providers are similar, the only difference being that the pressing stroke range of the X-axis is tested more precisely, and the unit of displacement of the key shaft 31 is μm (micrometer), which is also mentioned here for reference.

[0032] Please refer to Figure 6The diagram shown is a side cross-sectional view and magnetic field lines of another embodiment of the inductive magnetic levitation keyboard of the present invention. It provides that the first magnetic body 2 and the induction coil 11 are offset, and the first magnetic body 2 and the second magnetic body 4 are also offset. From their magnetic field lines, it can be seen that the smaller overlap area reduces the repulsive force, which is beneficial for adjusting (reducing) the magnetic levitation force within the limited space of the keyboard. Conversely, Figure 1 The first magnetic body 2 is aligned with the induction coil 11, and the first magnetic body 2 and the second magnetic body 4 are also aligned. The magnetic field lines show that this alignment increases the repulsive force, which is beneficial for using the smaller and less magnetically powerful first magnetic body 2 and second magnetic body 4 to achieve magnetic levitation. Furthermore, the first magnetic body 2 and the second magnetic body 4 are permanent magnets made of neodymium iron boron (NdFeB) material. NdFeB magnets are generally inexpensive due to their smaller size, which helps reduce the overall manufacturing cost of the keyboard.

[0033] Please refer to Figure 7 The image shown is a side cross-sectional view of another embodiment of the inductive magnetic levitation keyboard of the present invention. Figure 1 The only difference is that the first magnetic body 2 is made of an electromagnet. The advantage of using an electromagnet is that the current value passing through the coil outside the iron core can be controlled to adjust the magnetic levitation force matching between the first magnetic body 2 and the second magnetic body 4, and it can be applied to keyboards of different specifications.

[0034] The main features of this invention are: a linear key travel is formed by the mutual repulsion between the first magnetic body 2 and the second magnetic body 4, and the force required to press the key can be adjusted by changing the magnetic flux between the first magnetic body 2 and the second magnetic body 4; furthermore, whether the inductance value of the second magnetic body 4 in the key shaft 31 sensed by the induction coil 11 is greater than a predetermined threshold determines whether the control unit generates a trigger signal, thus eliminating the need for the structure of sensing the magnetic field strength of the magnetic body through the Hall element in the prior art, thereby saving the cost of keyboard manufacturing, and avoiding the additional magnetic interference that the two magnets with mutual repulsion or attraction would generate on the Hall element.

[0035] The above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Therefore, any simple modifications and equivalent structural changes made based on the description and drawings of the present invention should also be included within the protection scope of the present invention and are hereby stated.

[0036] In summary, the inductive magnetic levitation keyboard described above can effectively achieve its function and purpose when in use, thus this invention is indeed a highly practical invention.

Claims

1. An inductive magnetic levitation keyboard, comprising a pre-set base located below and a pre-set outer shell with multiple hollowed-out sections attached to the upper part, characterized in that, The inductive magnetic levitation keyboard includes: A circuit board is fixed between the preset base and the preset housing. The circuit board includes multiple sensing coils corresponding to multiple buttons, and the multiple sensing coils are coupled to the preset control unit through a line. Multiple first magnetic bodies are disposed in the preset base and below the multiple induction coils of the circuit board; and Multiple key shafts are disposed on multiple induction coils on the circuit board. Each key shaft has a keycap exposed in the cutout of the preset housing, forming multiple buttons. Each key shaft has a second magnetic body with conductive metal properties. The key shaft is positioned by interference with the preset housing through a preset limiting mechanism. The first magnetic body and the second magnetic body have a repulsive force and lift the key shaft to form a magnetic levitation state. When each key shaft is in the upper position and the inductance value of the second magnetic body sensed by the induction coil is less than a predetermined threshold, the preset control unit coupled to the induction coil does not generate a trigger signal. When each key shaft moves downward toward the induction coil and the inductance value of the second magnetic body sensed is greater than the predetermined threshold, the preset control unit generates a trigger signal.

2. The inductive magnetic levitation keyboard as described in claim 1, characterized in that, The first magnetic object is positioned in alignment with the induction coil.

3. The inductive magnetic levitation keyboard as described in claim 1, characterized in that, The first magnetic object is offset from the induction coil.

4. The inductive magnetic levitation keyboard as described in claim 1, characterized in that, The first magnetic body is a permanent magnet made of neodymium iron boron material, or an electromagnet.

5. The inductive magnetic levitation keyboard as described in claim 1, characterized in that, The second magnetic body is a permanent magnet made of neodymium iron boron material.

6. The inductive magnetic levitation keyboard as described in claim 1, characterized in that, The induction coil has a circular or rectangular spiral structure.

7. The inductive magnetic levitation keyboard as described in claim 6, characterized in that, When the induction coil has a circular spiral structure, it generates a magnetic field with a height h = Dout1 / 2, where Dout1 is the diameter of the circle.

8. The inductive magnetic levitation keyboard as described in claim 6, characterized in that, When the induction coil is constructed in a rectangular spiral shape, it generates a magnetic field with a height h = Dout2 / 2, where Dout2 is the length of the shorter side of the rectangle.

9. The inductive magnetic levitation keyboard as described in claim 1, characterized in that, A key seat is also installed on the bottom side of the key shaft, and the second magnetic body is embedded and fixed between the key shaft and the key seat. The assembly structure of the key shaft and the key seat forms a magnetic levitation state through the mutual repulsion between the first magnetic body and the second magnetic body.

10. The inductive magnetic levitation keyboard as described in claim 1, characterized in that, When the second magnetic body approaches the magnetic field of the induction coil, it can induce eddy currents inside, and the eddy currents cause the second magnetic body to generate a magnetic field opposite to that of the induction coil, thereby changing the inductance of the induction coil.

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