Key module and electronic device

Abstract

The utility model discloses the technical field of a kind of key module and electronic equipment, the key module, comprising: physical key, circuit board and structural member;Structural member is wrapped circuit board and is fixed with physical key clamping, and physical key is set on the upper of circuit board;Circuit board is provided with electromagnetic protection circuit, backlight illumination circuit, self-adapting photosensitive circuit and key protection circuit, and structural member includes upper shell, back cover and sealing ring.The key module can be in widely geographical area, under complex electromagnetic environment, provide stable and reliable and have self-adapting switch backlight function's key module, and can be flexibly adapted to multiple host equipment.

Description

Technical Field

[0001] This utility model relates to the field of button technology, and in particular to a button module and electronic device. Background Technology

[0002] Buttons are widely used across various industries, including aerospace, medical equipment, industrial automation, white goods, electronic devices, automobiles, tools, communications, and the power industry. One of their primary functions is as a state transition control or on / off control. For a system, buttons typically serve as the system's state input, and the system's control core determines further actions based on the button's input state. Therefore, a reliable button, especially capable of reliably performing its designed function in harsh environments, is crucial.

[0003] Among the aforementioned industries, aerospace applications, in particular, face complex and harsh environments, demanding extremely high reliability and durability from buttons. Typical application environments include complex electromagnetic environments and adaptive human-machine interface requirements.

[0004] However, current improvements to button modules focus on mechanical design and aesthetic enhancement, which are applicable to consumer terminals. Most of these improvements do not consider electrical and adaptive application scenarios, electromagnetic compatibility (EMC) capabilities, resulting in failure to meet stability requirements in harsh environments. Utility Model Content

[0005] This application provides a button module and electronic device suitable for harsh environments, solving the problem of insufficient stability of button modules in harsh environments in the prior art; and achieving stable and reliable technical effects in a wide geographical area and complex electromagnetic environment.

[0006] This application provides a button module, including: physical buttons, a circuit board, and structural components; the structural components enclose the circuit board and engage with and fix the physical buttons, the physical buttons being disposed above the circuit board; the circuit board is provided with an electromagnetic protection circuit, a backlight illumination circuit, an adaptive light-sensing circuit, and a button protection circuit, and the structural components include an upper shell, a rear cover plate, and a sealing ring.

[0007] The beneficial effects of the above embodiments are that the button module can provide a stable and reliable button module with adaptive switching backlight function in a wide geographical area and complex electromagnetic environment, and can be flexibly adapted to a variety of host devices.

[0008] Based on the above embodiments, this application can be further improved as follows: In one embodiment of this application, the physical button includes a button post and a dome switch. A chuck is provided at the bottom of the button post, and a slot matching the chuck is provided on the inner wall of the upper housing. The dome switch is fixed to the circuit board, and the button post is fixed above the dome switch by the chuck and the slot. Technical advantages: The mechanical cooperation between the chuck and the slot enables rapid assembly and stable fixing of the button post. Simultaneously, the elastic structure of the dome switch ensures reliable circuit continuity when the button is pressed, reducing assembly difficulty and extending service life.

[0009] In one embodiment of this application, the button post is made of aviation-grade acrylic glass YB-3, and the surface of the button post is provided with a silkscreen layer, which is a light-transmitting structure. Technical advantages: Aviation-grade acrylic glass YB-3 possesses high strength and weather resistance, adapting to harsh environments; the light-transmitting layer allows backlight LED light to pass through, ensuring clear button recognition in dark environments.

[0010] In one embodiment of this application, the electromagnetic protection circuit includes a two-stage power supply filtering unit. The two-stage power supply filtering unit sequentially includes a filter and a common-mode inductor. The input terminal of the filter is connected to an external power supply, and the output terminal of the common-mode inductor is connected to the backlight illumination circuit, the adaptive photosensor circuit, and the button protection circuit. Technical effect: The two-stage filtering structure suppresses conducted interference through a dedicated filter and suppresses electromagnetic radiation through the common-mode inductor, enabling the module to meet EMC test requirements such as CE102, CS114, and CS115, thus improving electromagnetic compatibility.

[0011] In one embodiment of this application, the backlight circuit includes a blue-white LED powered by 12V DC. The LED is disposed beside the dome switch and is driven by an external host device via PWM control. The brightness range of the LED is 1.7–5.1 cd / m². 2 Technical performance: Blue-white LED lights have an efficiency of 1.7–5.1 cd / m². 2 Within the brightness range, it can meet the button recognition requirements in dark environments while avoiding glare from strong light, meeting the lighting standards for military equipment and improving the human-computer interaction experience.

[0012] In one embodiment of this application, the adaptive photoelectric router consists of a photosensitive sensor, a signal processing circuit, and an IIC isolation interface circuit. The photosensitive sensor senses the ambient light intensity and converts changes in ambient brightness into current. The signal processing circuit converts the current generated by the photosensitive sensor into voltage, and transmits the voltage value to the host device through the IIC isolation interface circuit. Technical effect: The photosensitive sensor detects the ambient light intensity in real time and transmits the signal to the host device through the IIC isolation interface. The host device then decides to turn the backlight LED on or off based on the real-time measured light intensity, achieving adaptive switching and dimming of the backlight LED. Simultaneously, the isolated IIC interface circuit can isolate external interference from the device, protecting the host device from interference such as static electricity from the human body (CS112).

[0013] In one embodiment of this application, the button protection circuit includes a TVS diode and a ferrite bead connected in series in the button circuit. The ferrite bead is disposed at the output terminal of the dome switch, and the TVS diode is grounded. Technical effect: The ferrite bead absorbs interference, and the TVS diode conducts the interference to the host device structure. This dual protection ensures the stability of the button state, avoids false triggering caused by electrostatic or electromagnetic interference, and improves button control accuracy.

[0014] In one embodiment of this application, a conductive adhesive strip is provided at the joint between the upper housing and the rear cover plate, conductive paint is sprayed onto the inner walls of the upper housing and the rear cover plate, and a transparent conductive film is covered on the surface of the circuit board. Technical effects: The conductive adhesive strip and conductive paint form an electromagnetic shielding cavity, and the transparent conductive film wrapping the PCB further enhances the shielding effectiveness, reduces electromagnetic radiation and external interference, and adapts to complex electromagnetic environments (such as aerospace scenarios).

[0015] This application provides an electronic device including any of the aforementioned button modules, wherein the electronic device is a handheld device, tablet computer, or individual soldier equipment. Technical advantages: By integrating a highly reliable button module, the electronic device achieves stable status input and control in harsh environments, expanding its application scenarios in aerospace, industrial automation, and other fields.

[0016] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages: 1. Environmental adaptability: The use of aerospace-grade acrylic glass, military-grade components, and a sealed structure design enables the module to withstand high and low temperatures, humidity, and salt spray testing requirements. 2. Electromagnetic compatibility: The two-stage power supply filtering and full-enclosed shielding design help the host device pass EMC tests such as CE102, CS112, and CS114, and adapt to complex electromagnetic environments. 3. Adaptive dimming: A photosensitive sensor detects light intensity in real time, and the host device controls the backlight LED switch via the IIC interface to achieve automatic supplemental lighting in dark environments and energy saving by turning off the backlight in bright environments, thus improving ease of operation. Attached Figure Description

[0017] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0018] Figure 1 This is a schematic diagram of the structure of a button module in an embodiment of this application; Figure 2 This is an exploded view of a button module in an embodiment of this application; Figure 3 This is an electrical schematic diagram of the circuit board in an embodiment of this application.

[0019] Among them, 11. button post, 12. chuck, 2. circuit board, 31. upper shell, 32. rear cover, 33. sealing ring. Detailed Implementation

[0020] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are only for illustrating the present invention and not for limiting the scope of the present invention. After reading the present invention, any modifications of the present invention in various equivalent forms by those skilled in the art will fall within the scope defined by the appended claims.

[0021] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0022] In the description of this utility model, it should be noted that the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0023] In the description of this utility model, the illustrative expressions of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate different embodiments or examples described in this utility model, as well as the features of different embodiments or examples.

[0024] This application provides a button module and electronic device suitable for harsh environments, solving the problem of insufficient stability of button modules in harsh environments in the prior art; and achieving stable and reliable technical effects in a wide geographical area and complex electromagnetic environment.

[0025] The technical solution in this application is to solve the above problems, and the overall approach is as follows: Example 1: like Figure 1-2 As shown, a button module includes: physical buttons, a circuit board 2, and structural components; the structural components enclose the circuit board 2 and engage with and fix the physical buttons, the physical buttons are located above the circuit board, and the structural components include an upper housing 31, a rear cover plate 32, and a sealing ring 33.

[0026] The physical button includes a button post 11 and a dome switch (not shown in the figure). A chuck 12 is located at the bottom of the button post 11, and a slot (not shown in the figure) matching the chuck 12 is located on the inner wall of the upper housing 31. The dome switch is fixed to the circuit board 2, and the button post 11 is secured above the dome switch by the chuck 12 engaging with the slot. When the user applies external pressure to the button post, the dome switch is connected to the circuit on the circuit board, forming an active state. After the external force is released, the dome switch returns to its original position, the circuit is disconnected, and the device returns to an open circuit state.

[0027] The button post is made of aviation-grade organic glass YB-3 (black). The surface of the button post has a silkscreen layer, which is light-transmitting and has a stroke of 0.5±0.2mm. This design ensures effective recognition of the status while reducing the overall height of the button module.

[0028] like Figure 3 As shown, the electrical components of the circuit board include an electromagnetic protection circuit, a backlight illumination circuit, an adaptive light-sensing circuit, and a key protection circuit. The electromagnetic protection circuit includes a two-stage power supply filtering unit, which consists of a filter and a common-mode inductor. The input of the dedicated filter is connected to an external power supply, which helps reduce conducted interference on the power supply and helps the host device pass CE102, CS114, and CS115 tests. The common-mode inductor further suppresses external interference and internal conducted emissions, and also protects the host device from damage. The power supply after two stages of protection is supplied to the backlight circuit, the adaptive photosensor circuit, and the button protection circuit.

[0029] The backlight circuit includes a 12V DC powered blue-white LED, with a brightness range of 1.7–5.1 cd / m². 2 This design allows users to clearly identify the buttons in dark environments. LEDs are positioned beside the dome switches, emitting blue-white light that passes through the button posts (made of organic aviation glass) so the buttons are visible to the user, thus providing backlighting. The backlight is controlled and turned off by an external host device via PWM.

[0030] The adaptive light-sensing circuit mainly consists of a photosensor, a signal processing circuit, and an IIC isolation interface circuit. The photosensor detects the intensity of ambient light and converts changes in ambient brightness into current. The signal processing circuit converts the current generated by the photosensor into voltage, which is then transmitted to the host device via the IIC isolation interface circuit. The host device then determines whether to turn the backlight LED on or off based on the real-time measured light intensity, achieving adaptive switching and dimming of the backlight LED. Simultaneously, the IIC isolation interface circuit isolates the device from external interference, protecting the host device from interference such as static electricity from the human body (CS112).

[0031] The backlighting circuit and adaptive light-sensing circuit function as follows: Due to the small size and high integration of this button module, it can be applied to equipment or instruments such as handheld devices, special tablets, and special individual soldier equipment. In applications such as individual soldier applications or drone control (tablets), users may operate the device around the clock, such as in dimly lit evenings or pitch-black nights. To support these usage scenarios, each button in this button module is equipped with an LED backlight indicator, the control of which is controlled by the actual host device. In addition, an adaptive light-sensing circuit is also included. Once the ambient light intensity is lower than the set "dark" threshold, the host device illuminates the backlight LEDs through the button module's drive circuit, creating button backlighting for easy user identification and operation; similarly, when the photosensor detects that the ambient light intensity exceeds the set "bright" threshold, the drive circuit turns off the LED indicator, saving energy for the host device.

[0032] The button protection circuit includes a TVS diode and a ferrite bead connected in series in the button circuit. The ferrite bead is located at the output terminal of the dome switch, and the TVS diode is grounded. The ferrite bead suppresses high-frequency interference, and the TVS diode absorbs electrostatic pulses. This dual protection ensures the stability of the button signal, avoids false triggering caused by electrostatic or electromagnetic interference, and improves the button control accuracy.

[0033] The function of the button protection circuit is as follows: Users frequently press the buttons, and in addition, various qualification tests are required during the standard military equipment certification process, such as electromagnetic compatibility (EMC) tests. Both frequent button presses by users and the CS112 EMC test generate significant electrostatic interference. If this electrostatic interference is conducted to the host device through the buttons, it may cause malfunctions or even damage to the host device's core controller. By incorporating protective devices (such as ferrite beads and TVS diodes) into the button circuitry, the ferrite beads absorb interference, and the TVS diodes conduct it away, effectively protecting against electrostatic interference and enhancing the electromagnetic protection capability of the button module.

[0034] This solution employs two-stage power supply filtering, button protection, and IIC communication interface isolation protection in its electrical aspects. These measures are all aimed at enhancing the module's electromagnetic protection capabilities. In addition to the above methods, the overall electromagnetic compatibility performance of the module is further improved through the following means: 1. The joint between the upper housing and the rear cover is sealed with conductive adhesive strips, and the inner walls of the upper housing and the rear cover are coated with conductive paint; 2. The circuit board surface is wrapped with a transparent conductive film.

[0035] Conductive adhesive strips and conductive paint form an electromagnetic shielding cavity, and a transparent conductive film wraps the circuit board to further enhance shielding effectiveness, reduce electromagnetic radiation and external interference, and adapt to complex electromagnetic environments (such as aerospace scenarios).

[0036] The technical solutions described in the embodiments of this application have at least the following technical effects or advantages: 1. Environmental adaptability: The use of aerospace-grade acrylic glass, military-grade components, and a sealed structure design enables the module to withstand high and low temperatures, humidity, and salt spray testing requirements. 2. Electromagnetic compatibility: The two-stage power supply filtering and full-enclosed shielding design help the host device pass EMC tests such as CE102, CS112, and CS114, and adapt to complex electromagnetic environments. 3. Adaptive dimming: A photosensitive sensor detects light intensity in real time, and the host device controls the backlight LED switch via the IIC interface to achieve automatic supplemental lighting in dark environments and energy saving by turning off the backlight in bright environments, thus improving ease of operation.

[0037] 4. An electromagnetic shielding cavity is formed by conductive adhesive strips and conductive paint, and a transparent conductive film is wrapped around the circuit board to further improve the shielding effectiveness, reduce electromagnetic radiation and external interference, and adapt to complex electromagnetic environments (such as aerospace scenarios).

[0038] Example 2: An electronic device includes a button module as shown in Embodiment 1. The electronic device can be a handheld device, a special tablet computer, or individual soldier equipment. By integrating a highly reliable button module, the electronic device can achieve stable status input and control in harsh environments, expanding its application scenarios in aerospace, industrial automation, and other fields.

[0039] This button module is already in normal use on a 10.1-inch handheld tablet. The tablet as a whole has passed third-party testing to verify its environmental adaptability (GJB150-2009 high and low temperature test, damp heat test, transportation vibration test) and EMC performance (GJB151B-2013 CS112 test items).

[0040] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A button module, characterized in that, include: Physical buttons, circuit boards, and structural components; the structural components enclose the circuit board and engage with and fix the physical buttons, which are positioned above the circuit board; the circuit board is equipped with an electromagnetic protection circuit, a backlight illumination circuit, an adaptive light-sensing circuit, and a button protection circuit; the structural components include an upper housing, a rear cover, and a sealing ring.

2. The button module according to claim 1, characterized in that: The physical button includes a button post and a dome switch. The bottom of the button post is provided with a chuck, and the inner wall of the upper housing is provided with a slot that matches the chuck. The dome switch is fixed to the circuit board, and the button post is fixed above the dome switch by the chuck and the slot.

3. The button module according to claim 2, characterized in that: The button post is made of aviation-grade organic glass YB-3, and the surface of the button post is covered with a silkscreen layer, which is a light-transmitting structure.

4. The button module according to claim 1, characterized in that: The electromagnetic protection circuit includes a two-stage power supply filtering unit, which includes a filter and a common-mode inductor in sequence. The input terminal of the filter is connected to an external power supply, and the output terminal of the common-mode inductor is connected to the backlight circuit, the adaptive light-sensing circuit, and the button protection circuit.

5. The button module according to claim 2, characterized in that: The backlight circuit includes an LED light, which is located next to the dome switch and is driven by an external host device via PWM control.

6. The button module according to claim 1, characterized in that: The adaptive photoelectric router consists of a photosensitive sensor, a signal processing circuit, and an IIC isolation interface circuit. The photosensitive sensor converts changes in external brightness into current, the signal processing circuit converts the current generated by the photosensitive sensor into voltage, and the voltage value is transmitted to the host device through the IIC isolation interface circuit.

7. The button module according to claim 2, characterized in that: The button protection circuit includes a TVS diode and a ferrite bead connected in series in the button circuit. The ferrite bead is located at the output terminal of the dome switch, and the TVS diode is grounded.

8. The button module according to claim 1, characterized in that: Conductive adhesive strips are provided at the joint between the upper housing and the rear cover plate. Conductive paint is sprayed on the inner walls of the upper housing and the rear cover plate. A transparent conductive film is covered on the surface of the circuit board.

9. An electronic device, characterized in that: Includes the button module as described in any one of claims 1-8, wherein the electronic device is a handheld device, a tablet computer, or individual soldier equipment.

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