A low-radiation flat panel computer

Abstract

The application discloses a low-leakage panel computer, and relates to the technical field of electronic equipment. The low-leakage panel computer comprises a front shell, a middle frame and a back cover which are all capable of conducting electricity; the front shell is fixedly connected with the middle frame, and the front shell and the middle frame form a first sealed cavity; a prototype machine panel computer is arranged in the first sealed cavity; a touch screen is installed on the front shell and corresponds to the prototype machine panel computer; an electromagnetic shielding layer is integrally arranged on the side of the touch screen close to the prototype machine panel computer; the electromagnetic shielding layer is electrically connected with the front shell through a conductive part; the middle frame is fixedly connected with the back cover, and the middle frame and the back cover form a second sealed cavity; the prototype machine panel computer is matched with a main control board and a driving board; a third sealed cavity for placing the main control board and the driving board is arranged on the back cover; the third sealed cavity is arranged in the second sealed cavity; and the main control board, the driving board, an external interface board and other electronic devices are arranged in the multiple sealed cavities, so that electromagnetic protection is simultaneously achieved on the prototype machine panel computer and the external electronic devices.

Description

Technical Field

[0001] This invention relates to the field of electronic device technology, and in particular to a low-emission tablet computer. Background Technology

[0002] With the rapid development of the information industry, tablet computers have been widely used in highly confidential office systems for information collection, transmission, and processing. Low-leakage tablet computers include necessary hardware components such as LCD screens, touchscreens, and circuit boards. The display screen and touchscreen are the windows for information processing; during operation, they generate strong electromagnetic radiation. This radiated electromagnetic field not only interferes with various electronic devices, but the information emitted is also easily intercepted and reproduced, making it a crucial avenue for intelligence personnel to steal military and commercial intelligence. Therefore, it is necessary to improve existing tablet computers by enhancing their electromagnetic shielding protection level to overcome the problem of easily stolen important intelligence due to their strong electromagnetic radiation.

[0003] To address this issue, a utility model application with application number "202222878269.2" and titled "A Low-Emission Tablet PC" was disclosed. The invention includes a frame, a shielding part on one side of the frame, a touch-sensitive part on one side of the shielding part, the touch-sensitive part being tightly fitted to the shielding part, a display screen on one side of the touch-sensitive part, pressure plates around the shielding part, a threaded groove inside the frame, bolts threaded into the groove, one side of the pressure plate tightly fitted to one end of the bolts, a back cover on one side of the frame, a metal mesh gasket between the back cover and the frame, the frame being made of low-carbon alloy structural steel, the pressure plates being Z-shaped, and an integrated filter threaded into the frame. The shielding part effectively shields the touch screen, preventing information leakage. However, this solution only improves the electromagnetic shielding of ordinary tablet PCs, and the protection effect is relatively poor. Furthermore, in practical use, the functionality of a tablet PC is limited by its own design, requiring external electrical accessories to meet usage needs.

[0004] Therefore, this invention develops a low-emission tablet computer to solve the above-mentioned technical problems. Summary of the Invention

[0005] The purpose of this invention is to provide a low-emission tablet computer to solve the problems existing in the prior art, improve the electromagnetic shielding protection level of existing external electronic accessories for tablet computers, prevent important information from being easily stolen, and also enhance the anti-interference capability of the device.

[0006] To achieve the above objectives, the present invention provides the following solution:

[0007] This invention provides a low-emission tablet computer, comprising: a front shell, a middle frame, and a back cover, all of which are electrically conductive;

[0008] The front shell is fixedly connected to the middle frame, and the front shell and the middle frame form a first sealed cavity; a prototype tablet computer is placed in the first sealed cavity, and the prototype tablet computer is fixedly connected to the middle frame; a touch screen is installed on the front shell at the position corresponding to the prototype tablet computer; the side of the touch screen close to the prototype tablet computer is entirely covered with an electromagnetic shielding layer; the electromagnetic shielding layer is electrically connected to the front shell through a conductive component.

[0009] The middle frame is fixedly connected to the back cover, and the middle frame and the back cover form a second sealed cavity; the prototype tablet computer is equipped with a main control board and a drive board, and the back cover is provided with a third sealed cavity for placing the main control board and the drive board; the third sealed cavity is located inside the second sealed cavity.

[0010] Preferably, the electromagnetic shielding layer is electromagnetic shielding glass, electromagnetic shielding mesh, or electromagnetic shielding film; the conductive component is copper foil; one end of the copper foil is bonded to the electromagnetic shielding layer, and the other end is bonded to the front shell.

[0011] Preferably, the edge of the middle frame is provided with a groove corresponding to the front shell and the rear cover; the front shell and the rear cover are provided with protrusions that correspond to the grooves; and a conductive rubber strip is provided between the grooves provided at the edge of the middle frame corresponding to the front shell and the rear cover and the protrusions that correspond to the front shell and the rear cover.

[0012] Preferably, the rear cover has annular protrusions for placing the main control board and the drive board respectively; the middle frame has an isolation plate; the upper end of the annular protrusion has an annular groove for placing a conductive rubber strip; the conductive rubber strip is located between the annular protrusion and the isolation plate; the annular protrusion and the isolation plate form a third sealed cavity.

[0013] Preferably, the middle frame has a first outlet for the lines of the prototype tablet computer and the touch screen to be led out; the first outlet is sealed by wrapping the lines with copper foil.

[0014] Preferably, the drive board is provided with a first conductive busbar around its perimeter; the copper foil is pasted around the first conductive busbar and overlaps with the isolation plate.

[0015] Preferably, a battery, a battery management board, and an external interface board are also fixedly installed inside the rear cover; the annular protrusion is provided with a second outlet for the main control board circuitry and the drive board circuitry; the second outlet is sealed by wrapping the circuitry with copper foil; the external interface board is connected to the main control board via a first shielded cable; the battery management board is connected to the external interface board via a second shielded cable; the drive board is connected to the external interface board via a third shielded cable; and the battery and the battery management board are connected via a fourth shielded cable.

[0016] Preferably, the back cover has a rear camera opening at a position corresponding to the rear camera of the prototype tablet computer; an electromagnetic shielding layer is fixedly installed at the position of the rear camera opening.

[0017] Preferably, the external interface board is provided with a reserved interface for electrical connection with the prototype tablet computer and a plurality of external interface connectors; the rear cover is provided with a plurality of alignment interface openings corresponding to the plurality of external interface connectors.

[0018] Preferably, it also includes a communication antenna assembly, a filter, and a filtering circuit;

[0019] The communication antenna assembly is fixedly installed on the outer side of the rear cover;

[0020] The filter is located in the second sealed cavity and is fixedly installed on the rear cover; one end of the filter is electrically connected to the communication antenna assembly; the other end of the filter is electrically connected to the communication interface on the main control board.

[0021] The filtering circuit is mounted on the external interface board and located at the rear end of the external interface connector; the filtering circuit is electrically connected to the external interface connector.

[0022] The present invention achieves the following technical effects compared to the prior art:

[0023] 1. In this invention, the front shell and the middle frame form a first sealed cavity, the middle frame and the rear cover form a second sealed cavity, and the rear cover is provided with annular protrusions for placing the main control board and the drive board respectively; the annular protrusions and the isolation plate form a third sealed cavity, which seals and isolates the main control board and the drive board, avoiding mutual interference between the main control board, the drive board and the electronic component circuits. At the same time, the third sealed cavity can improve the electromagnetic shielding effect of the main control board and the drive board. The function of preventing electromagnetic wave leakage is achieved through multiple sealed cavities, resulting in better protection.

[0024] 2. This invention enhances the functionality of the prototype tablet computer by installing electronic components such as the main control board, driver board, and external interface board on the back cover. Furthermore, by installing these electronic components inside multiple sealed cavities, electromagnetic protection is simultaneously provided for both the prototype tablet computer and external electronic components.

[0025] 3. This invention achieves electromagnetic protection at the external interface by setting a filter circuit on the external interface board;

[0026] 4. This invention improves shielding performance by installing a communication antenna assembly on the outside of the rear shell and connecting a filter to the rear end of the communication antenna assembly to receive and transmit electromagnetic wave signals in a specified frequency band. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1-5 This is a schematic diagram of the overall assembly structure of the present invention;

[0029] Figure 6 This is an exploded view of the front shell, the first silicone rubber plate, and the touch screen of the present invention.

[0030] Figure 7 This is an exploded view of the middle frame and the parts mounted on the middle frame of the present invention;

[0031] Figure 8 This is an exploded view of the rear cover and parts mounted on the rear cover of the present invention;

[0032] Figure 9 This is a partial structural diagram of the frame in this invention;

[0033] Figure 10-11 A schematic diagram of the assembly structure of the custom rubber stopper and the custom rubber stopper bracket of this invention;

[0034] Figure 12-13 This is a schematic diagram of the assembly structure of the sliding door assembly and the back cover of the present invention;

[0035] Figure 14 This is a cross-sectional structural diagram of the sliding door assembly and the rear cover of the present invention;

[0036] Figure 15 This is a schematic diagram of the assembly structure of the sliding door and sliding door assembly of the present invention;

[0037] Figure 16-17This is a schematic diagram of the structure of the sliding door assembly of the present invention;

[0038] Figure 18 This is a schematic diagram of the assembly structure of the back cover and communication antenna assembly of the present invention;

[0039] Figure 19 This is a schematic cross-sectional view of the front shell, the first silicone rubber plate, the touch screen, the electromagnetic shielding layer, and the copper foil of the present invention.

[0040] Figure 20 This is a schematic diagram showing the connection relationship of various devices in a low-emission tablet computer disclosed in an embodiment of the present invention.

[0041] Among them, 100, tablet computer; 1, front shell; 2, middle frame; 3, back cover; 4, buttons; 5, button guide shaft; 6, prototype tablet computer; 7, custom rubber plug; 8, rubber plug fixing bracket; 9, first silicone rubber plate; 12, external interface board; 13, main control board; 14, driver board; 15, battery; 16, battery management board; 17, self-reset button; 18, sliding door assembly (1801, sliding door; 1802, sliding door bracket; 1803, spring plunger); 19 20. Electromagnetic shielding glass; 21. Touch screen; 22. First antenna housing; 23. Second antenna housing; 24. First filter; 25. Second filter; 26. Third filter; 27. First communication antenna; 28. Second communication antenna; 29. ​​Third communication antenna; 30. Type-C shielded cable; 31. Folding bracket assembly (3001. Bracket; 3002. Damping hinge; 3003. Bracket decorative cover); 30. First shielded cable; 31. Second shielded cable. Detailed Implementation

[0042] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] The purpose of this invention is to provide a low-emission tablet computer to solve the problems existing in the prior art, improve the electromagnetic shielding protection level of existing external electronic accessories for tablet computers, prevent important information from being easily stolen, and also enhance the anti-interference capability of the device.

[0044] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0045] Example

[0046] This embodiment provides a low-emission tablet computer 100, such as... Figure 1-8 As shown,

[0047] A low-emission tablet computer, characterized in that it comprises: a front shell 1, a middle frame 2, and a back cover 3, all of which are capable of conducting electricity;

[0048] The front shell 1 and the middle frame 2 are fixedly connected by bolts, and the front shell 1 and the middle frame 2 form a first sealed cavity; the prototype tablet computer 6 is placed in the first sealed cavity, and the prototype tablet computer 6 is fixedly connected to the middle frame 2; a touch screen 20 is installed on the front shell 1 at the position corresponding to the prototype tablet computer 6; the side of the touch screen 20 close to the prototype tablet computer 6 is entirely covered with an electromagnetic shielding layer; the electromagnetic shielding layer is electrically connected to the front shell 1 through a conductive component.

[0049] The middle frame 2 and the back cover 3 are fixedly connected by bolts, and the middle frame 2 and the back cover 3 form a second sealed cavity; the prototype tablet computer 6 is equipped with a main control board 13 and a drive board 14, and the back cover 3 is provided with a third sealed cavity for placing the main control board 13 and the drive board 14; the third sealed cavity is located inside the second sealed cavity.

[0050] Furthermore, the front shell 1, middle frame 2, and rear cover 3 are all made of AZ91 D magnesium alloy, and the surfaces of the front shell 1, middle frame 2, and rear cover 3 are all treated with conductive coating. AZ91 D magnesium alloy has superior initial shielding effectiveness. By treating the surfaces of the front shell 1, middle frame 2, and rear cover 3 with conductive coating, a continuous conductive path is ensured, avoiding shielding blind spots caused by oxidation of the outer surface.

[0051] As a specific implementation method of this embodiment, such as Figure 6 and Figure 19 As shown, a first silicone rubber plate 9 is provided between the front shell 1 and the prototype tablet computer 6. The first silicone rubber plate 9 is elastic and can absorb external impacts to prevent the touch screen 20 from being damaged when the front shell 1 is bumped. In addition, because the first silicone rubber plate 9 is elastic, it can better fit with the front shell 1 and the touch screen 20, preventing dust and water from entering the first sealed cavity from the gap between the front shell 1 and the touch screen 20.

[0052] Furthermore, the electromagnetic shielding layer is electromagnetic shielding glass, electromagnetic shielding mesh, or electromagnetic shielding film; in this embodiment, the electromagnetic shielding layer uses an electromagnetic shielding film; the electromagnetic shielding film is fully bonded to the touch screen 20; the conductive component is copper foil; one end of the copper foil is pasted to the electromagnetic shielding film, and the other end is pasted to the front shell 1. The copper foil enables the electromagnetic shielding film to be electrically connected to the front shell 1.

[0053] Furthermore, grooves are provided at the edges of the middle frame 2 corresponding to the front shell 1 and the rear cover 3; protrusions corresponding to the grooves are provided on the front shell 1 and the rear cover 3; a conductive rubber strip is provided between the grooves at the edges of the middle frame 2 corresponding to the front shell 1 and the rear cover 3 and the protrusions corresponding to the front shell 1 and the rear cover 3. As a specific embodiment of this invention, the groove at the edges of the middle frame 2 corresponding to the front shell 1 and the rear cover 3 is an annular groove, which conforms to the outer contour of the middle frame 2; a conductive rubber strip is placed in the annular groove; the conductive rubber strip can fill the gap between the groove and the protrusion, constructing a continuous conductive path, and together with the front shell 1 and the middle frame 2, and the middle frame 2 and the rear cover 3, they form a complete Faraday cage, namely the first sealing cavity and the second sealing cavity.

[0054] As a specific implementation method of this embodiment, such as Figure 7 and Figure 9 As shown, the middle frame 2 is provided with a mounting slot for mounting the prototype tablet computer 6; the prototype tablet computer 6 is fixedly installed in the mounting slot, and a second silicone rubber plate is filled between the prototype tablet computer 6 and the side wall of the mounting slot; the second silicone rubber plate fits the prototype tablet computer 6 more closely, increasing the stability of the prototype tablet computer 6 while playing a role in vibration and impact resistance.

[0055] The front shell 1 and the touch screen 20 (including the electromagnetic shielding layer) are provided with a clearance structure at the corresponding position of the front camera of the prototype tablet computer 6 to avoid obstructing the front camera; as a specific implementation of this embodiment, the touch screen 20 consists of an outer mounting frame and a screen installed in the outer mounting frame; the outer mounting frame is installed on the front shell 1, and the outer mounting frame is provided with a semi-circular notch to avoid obstructing the front camera of the prototype tablet computer 6; the middle frame 2 is provided with a hole corresponding to the speaker hole of the prototype tablet computer 6 so that the sound can be transmitted normally to the outside. The middle frame 2 has button mounting grooves at positions corresponding to the volume and power buttons on the prototype tablet computer 6. Buttons 4 are mounted in these grooves via bolts. Each groove has a first through hole for the bolt to pass through, and the bolt corresponds to the volume or power button on the prototype tablet computer 6 at its respective position. Buttons 4 are connected to the middle frame 2 via bolts with a 0.5mm clearance, allowing them to move in the direction of the volume or power button on the prototype tablet computer 6. To precisely control the movement of buttons 4, each button 4 is threaded with two button guide shafts 5. The button mounting grooves have through holes for these guide shafts, and the direction of these holes is the same as the movement direction of the corresponding volume or power button on the prototype tablet computer 6. To control the volume or power button, simply press the corresponding button 4. Button 4 moves the bolt downwards, pressing one end of the bolt against the corresponding volume or power button on the prototype tablet computer 6. Releasing button 4 resets the corresponding button 4.

[0056] The prototype tablet computer 6 is located in the first sealed cavity. The first sealed cavity can effectively block the electromagnetic waves generated by the prototype tablet computer 6, prevent electromagnetic waves from leaking out, and increase the safety of the device.

[0057] Furthermore, such as Figure 8 As shown, the rear cover 3 has annular protrusions for placing the main control board 13 and the drive board 14 respectively; the main control board 13 and the drive board 14 are fixedly installed in the two annular protrusions respectively; the middle frame 2 has an isolation plate; each annular protrusion has an annular groove for placing a conductive rubber strip at its upper end; the conductive rubber strip is located between the annular protrusion and the isolation plate; the annular protrusion and the isolation plate form a third sealed cavity; the conductive rubber strip can fill the gap between the annular protrusion and the isolation plate, construct a continuous conductive path, and together with the annular protrusion and the isolation plate, form a complete Faraday cage, that is, the third sealed cavity.

[0058] Furthermore, the drive board 14 is provided with a first conductive busbar around its perimeter; copper foil is pasted around the first conductive busbar and overlaps with the isolation plate; as a specific embodiment of this example, the main control board 13 is provided with a second conductive busbar around its perimeter; copper foil is pasted around the second conductive busbar and overlaps with the isolation plate.

[0059] The main control board 13 and the drive board 14 are respectively installed in the two third sealed cavities. The third sealed cavities can prevent the electromagnetic waves generated by the main control board 13 and the drive board 14 from spreading outward. The two third sealed cavities isolate the main control board 13 and the drive board 14, avoiding mutual interference. At the same time, when the electromagnetic waves generated by the main control board 13 and the drive board 14 spread upward, they need to pass through the third sealed cavity, the second sealed cavity and the first sealed cavity to spread to the outside. Therefore, this application enhances the function of the prototype tablet computer 6 by adding electronic components, while better preventing the leakage of electromagnetic waves, and has a higher safety factor.

[0060] Furthermore, such as Figure 7-8 As shown, a battery 15, a battery management board 16, and an external interface board 12 are also fixedly installed inside the rear cover 3; the external interface board 12 is fixedly installed on the right side of the rear cover 3.

[0061] The annular protrusion has a second outlet for the main control board 13 and the drive board 14 lines; the second outlet is sealed by wrapping the lines with copper foil; the external interface board 12 is connected to the main control board 13 via a first shielded cable 31; the battery management board 16 is connected to the external interface board 12 via a second shielded cable 32; the drive board 14 is connected to the external interface board via a third shielded cable; the battery 15 and the battery management board 16 are connected via a fourth shielded cable; the middle frame 2 has a first outlet for the lines of the prototype tablet computer 6 and the touch screen 20; the first outlet is sealed by wrapping the lines with copper foil; by sealing the first and second outlets, the electromagnetic shielding effect at the locations of the first and second outlets can be enhanced, preventing electromagnetic waves from leaking out from the first and second outlets.

[0062] Furthermore, the external interface board 12 is equipped with a reserved interface for electrical connection with the prototype tablet computer 6 and multiple external interface connectors; the rear cover 3 is equipped with multiple external interface openings corresponding to the multiple external interface connectors; the middle frame 2 is equipped with a Type-C shielded cable routing groove. After the Type-C shielded cable 29 is inserted into the prototype tablet computer 6, it is installed in the corresponding position of the middle frame 2, and the other end of the Type-C shielded cable 29 is passed out from the first cable outlet and connected to the reserved interface on the external interface board 12. By connecting the prototype tablet computer 6 to the external interface board 12, the prototype tablet computer 6 is transformed from having only one external interface to having multiple external interfaces, which expands the function of the prototype tablet computer 6, supports the simultaneous access of multiple external devices, solves the compatibility bottleneck of the prototype's lack of interfaces, and eliminates the need for additional adapters, reducing the complexity of use and the cost of accessories, thus enhancing the practicality of the device.

[0063] As a specific implementation method of this embodiment, such as Figure 7and Figure 10-11 As shown, a rubber plug holder 8 is fixedly installed on one side of the middle frame 2 by bolts; the rubber plug holder 8 passes through one end of the custom rubber plug 7 and is fixedly installed on the middle frame 2, and fixes one end of the custom rubber plug 7 between the rubber plug holder 8 and the middle frame 2; the other end of the custom rubber plug 7 is provided with plugs that match the number of external interface openings; the plugs on the custom rubber plug 7 correspond one-to-one with the external interface openings on the back cover 3; dustproof and waterproof treatment is achieved by inserting the plugs on the custom rubber plug 7 into the external interface openings on the back cover 3.

[0064] Furthermore, such as Figure 8 and Figure 18 As shown, the back cover 3 has a rear camera opening at the position corresponding to the rear camera of the prototype tablet computer 6; an electromagnetic shielding layer is fixedly installed at the opening position; the electromagnetic shielding layer is electromagnetic shielding glass 19; the electromagnetic shielding glass 19 is electrically connected to the back cover 3 through copper foil; by opening the rear camera opening on the back cover 3, the rear camera of the prototype tablet computer 6 can be avoided from being blocked. At the same time, the electromagnetic shielding glass 19 at the rear camera opening position can effectively enhance the electromagnetic shielding effect at the rear camera and prevent electromagnetic waves from leaking out.

[0065] As a specific implementation method of this embodiment, such as Figure 8 and Figure 12-18 As shown, a sliding door assembly 18 is provided at the upper left corner of the back of the rear cover 3; the sliding door assembly 18 includes: a sliding door 1801, a sliding door bracket 1802, and a spring plunger 1803; a first self-reset switch is electrically connected to the external interface board 12, which in this embodiment is a first self-reset button 17; pressing the first self-reset button 17 can destroy the data inside the tablet computer 100; the upper left corner of the back of the rear cover 3 is provided with a sliding door assembly opening and an annular mounting recess, and a conductive rubber strip is installed in the annular mounting recess; the sliding door bracket 1802 is fixedly installed on the rear cover 3 by bolts; the sliding door bracket 1802 is provided with an annular protrusion corresponding to the annular mounting recess; the conductive rubber strip is located between the annular mounting recess and the annular protrusion, and is used to fill the gap between the annular mounting recess and the annular protrusion to construct a continuous conductive path;

[0066] The sliding door 1801 is slidably mounted on the sliding door bracket 1802 corresponding to the opening of the sliding door assembly. A push block is provided on the end of the sliding door 1801 facing away from the sliding door bracket 1802, and the push block is located inside the opening of the sliding door assembly, facilitating the sliding door 1801 to slide on the sliding door bracket 1802. In a specific embodiment, the sliding door 1801 is slidably mounted between the sliding door bracket 1802 and the rear cover 3, and the sliding door 1801 is larger than the opening of the sliding door assembly to block it. A 0.2mm protrusion is provided at the end of the sliding door 1801 that contacts the sliding door bracket 1802 and the end that contacts the rear cover 3 to reduce resistance during sliding and effectively protect the appearance from scratches. A mounting post is provided on the sliding door bracket 1802 for mounting a spring plunger 1803. The sliding door 1801 is connected to the mounting post... The mounting post is provided with a conical hole; the diameter of the conical hole is largest on the side away from the sliding door bracket 1802; the fixed end of the spring plunger 1803 slides into the mounting post through the conical hole and is fixedly connected to the mounting post; a through hole is provided at the center of the sliding door bracket 1802, and the position of the through hole corresponds to the self-reset button 17 on the external interface plate 12; when no external force is applied, the sliding door 1801 is in the closed state, that is, the sliding door 1801 blocks the through hole at the center of the sliding door bracket 1802, preventing the self-reset button 17 from being exposed; when it is necessary to destroy the data in the tablet computer 100, push the sliding door 1801 to slide, and the self-reset button 17 will be exposed. Press the self-reset button 17 to destroy the data; after the hand leaves the sliding door 1801, the sliding door 1801 will reset under the action of the spring plunger 1803, and block the self-reset button 17 again.

[0067] As a specific implementation of this embodiment, a second self-reset switch is fixedly installed on the back cover 3 and located in the second sealed cavity; the second self-reset switch is electrically connected to the external interface board 12 via a cable; in this embodiment, the second self-reset switch is a second self-reset button; after the middle frame 2 is fixedly connected to the back cover 3, the middle frame 2 presses the second self-reset button, so that the second self-reset button is in a pressed state; a destruction program is written into the tablet computer 100; when the middle frame 2 is removed from the back cover 3, the second self-reset button pops up, the destruction program is started, and the data in the tablet computer 100 is destroyed; to prevent the tablet computer 100 from being stolen and thus causing information leakage; when it is necessary to disassemble the tablet computer 100 by oneself, the destruction program is turned off by the program control in the tablet computer 100 before disassembling the tablet computer 100.

[0068] As a specific implementation method of this embodiment, such as Figure 8 and Figure 18As shown, a folding damping bracket 30 is installed on the back of the back cover 3; the folding damping bracket 30 includes: a bracket 3001, a damping hinge 3002, and a bracket decorative cover plate 3003; the back of the back cover 3 has a mounting groove for the bracket 3001; one end of the damping hinge 3002 is fixedly installed in the mounting groove of the back cover 3 by bolts; the other end of the damping hinge 3002 is fixedly connected to the bracket 3001 by bolts; the bracket decorative cover plate 3003 is fixedly installed on the damping hinge 3002 by bolts to cover the exposed part of the damping hinge 3002; the folding damping bracket 30 can solve the support problem when the computer is placed at different angles, and is easy to store, improving the convenience of using the tablet computer.

[0069] Furthermore, such as Figure 8 , Figure 18 and Figure 20 As shown, it also includes communication antenna components and filters;

[0070] A communication antenna assembly is fixedly installed on the outer side of the rear cover 3. The communication antenna assembly includes a first antenna housing 21 and a second antenna housing 22. Antenna housing mounting grooves are provided on both the upper and lower sides of the rear cover 3, for mounting the first antenna housing 21 and the second antenna housing 22 respectively. A first communication antenna 26 and a second communication antenna 27 are attached inside the first antenna housing 21. A third communication antenna 28 is attached inside the second antenna housing 22. Antenna wiring holes are provided at the mounting locations of the rear cover 3, the first antenna housing 21, and the second antenna housing 22. A first filter 23, a second filter 24, and a third filter 25 are fixedly installed inside the rear cover 3. The first antenna housing 21 and the second antenna housing 22 are both made of non-metallic material and are fixed to the rear cover 3 with bolts. The first communication antenna 26 is connected to the first filter 23 via a coaxial cable, the second communication antenna 27 is connected to the second filter 24 via a coaxial cable, and the third communication antenna 28 is connected to the third filter 25 via a coaxial cable. At the same time, the other ends of the first filter 23, the second filter 24, and the third filter 25 are also connected to the communication interface on the main control board 13 via coaxial cables.

[0071] As a specific implementation of this embodiment, all interconnecting cables are cables with shielding layers.

[0072] This device transmits signals through a communication antenna assembly. By setting a filter between the communication antenna assembly and the main control board 13, the communication antenna assembly can only accept and transmit electromagnetic waves of specific frequencies, preventing electromagnetic wave leakage and ensuring information security.

[0073] As a specific implementation of this embodiment, the filter used in this device is a custom filter; the signals received and transmitted by the first communication antenna 26 and the second communication antenna 27 are 4G signals, and the first filter 23 and the second filter 24 can allow three frequency bands to pass through, namely low frequency, medium frequency and high frequency; this improves network compatibility and anti-interference ability, solves the hardware redundancy problem of frequency band switching of traditional devices, and significantly improves communication survivability.

[0074] This device also transmits signals through a specific communication port, namely through the external interface connector on the external interface board 12;

[0075] Furthermore, a filtering circuit is also included; the filtering circuit is disposed on the external interface board 12 and located at the rear end of the external interface connector; the filtering circuit is electrically connected to the external interface connector; by providing a filtering circuit on the external interface board 12, electromagnetic leakage at the external interface is avoided. As a specific implementation of this embodiment, the filtering circuit includes: ESD protection devices for the signal matching module, a multi-stage filter bank, and a common-mode choke.

[0076] Furthermore, the battery management board 16 incorporates current limiting and charge / discharge voltage and current protection. It uses the MCU's built-in ADC to acquire the battery voltage and adapt it to the current charging and discharging current. It also features a temperature detection component to measure the battery and control board temperature in real time. To reduce output current ripple, the battery management board 16 does not use a boost converter; instead, it directly outputs the battery voltage, significantly reducing ripple interference. Additionally, it has a backup power output that provides current when the battery is low, ensuring that the device has sufficient time to save data.

[0077] Furthermore, both the external interface board 12 and the main control board 13 employ various measures to reduce the amount of signal radiation to the outside.

[0078] In component selection, low-radiation devices are crucial for reducing electromagnetic interference and improving electromagnetic compatibility. For IC selection, choose devices with integrated EMI suppression capabilities whenever possible, while also selecting those with low electromagnetic noise. For clock and oscillator selection, prioritize low-jitter clock sources to reduce high-frequency harmonic radiation; choose devices with shielded enclosures to minimize interference. For connectors, prioritize shielded connectors, such as Type-C, and ensure the connector housing is fully connected to the PCB ground. For power supply components, prioritize low-noise LDO devices; use DC-DC converters when voltage drop is too large; and prioritize modules with built-in filtering circuits to reduce high-frequency noise and minimize external component placement. For capacitors and resistors, prioritize decoupling capacitors and resistors with good high-frequency characteristics to minimize noise impact. For RF components, prioritize low-radiation modules compliant with FCC, CE, and other certifications to reduce antenna radiation leakage. In software configuration, setting device operating modes, such as sleep mode, can reduce clock frequency and shut down some circuits, thereby lowering radiation levels.

[0079] Furthermore, both the external interface board 12 and the main control board 13 adopt a multi-layer PCB design, with a complete ground plane in the inner layer to reduce electromagnetic interference, avoid ground plane segmentation, and ensure the integrity of the signal loop. Each has an independent power layer, which is recessed and uses a combination of single-point and multi-point grounding to avoid forming radiation loops. Differential traces are used for high-speed differential signals, effectively controlling line length and spacing while preventing other high-speed signals from near the differential lines. Grounding vias are applied to the differential signal perimeter to further improve signal quality and reduce external radiation. A filtering circuit is used at the board entry point, adding an LC filter circuit to the power lines to filter out high-frequency noise, and adding RC filters or ferrite beads to the signal lines to prevent signals from entering or radiating out. The boards adopt a modular layout, isolating circuits with different functions in separate areas to reduce mutual interference and ensuring that each area has an independent and single-point grounding point. High-radiation devices are specially treated; grounding vias are applied to the crystal oscillator section, and a no-route layer is placed below the crystal oscillator to minimize high-frequency signal coupling and crosstalk.

[0080] Furthermore, both the external interface board 12 and the main control board 13 adopt a multi-stage filter bank, consisting of a first-stage filter and a second-stage filter. The first-stage filter is set at the D+ / D- signal lines of the USB interface and all differential signal lines of the Type-C interface. The second-stage filter is set at the DATA and CLK signal lines of the SIM card interface and the signal line entrances of the network interface. Both the first-stage and second-stage filters include low-pass and high-pass filters to filter noise in different frequency bands.

[0081] Furthermore, the common-mode chokes of the external interface board 12 and the main control board 13 are set at the D+ / D- signal lines of the USB interface, all differential signal lines of the Type-C interface, and the signal line entrances of the network interface. The common-mode chokes include two magnetic rings with the same winding direction and connected in parallel. The common-mode chokes are used to eliminate common-mode noise and match line impedance, and reduce signal reflection.

[0082] Furthermore, the common ground network on the external interface board 12 and the main control board 13 is set on the bottom layer of the circuit board. The common ground network includes multiple ground layers, and each ground layer is connected by multiple vias with a spacing of 1.5mm. The multiple ground layers are connected by equally spaced vias. The common ground network is used to reduce the impedance of the ground lines and improve signal integrity.

[0083] Furthermore, the ESD protection devices of the USB interface protection and signal matching modules of the external interface board 12 and the main control board 13 are located at the D+ / D- signal line input of the USB interface. The ESD protection devices are TVS diode arrays. The surge suppressor is located between the USB interface power line (VBUS) and the ground line. The surge suppressor is a TVS diode. The common mode inductor is located on the D+ / D- signal line, and the resistance of the common mode inductor is 90Ω. The ESD protection devices of the all-differential lines of the Type-C and network interface protection modules are located at the input of all differential signal lines of the Type-C interface. The isolation capacitor is located on the USB 3.0 signal line, and the capacitance range of the isolation capacitor is 10nF to 100nF. The common mode inductor reuses the 90Ω common mode inductor of the D+ / D- signal line.

[0084] Furthermore, the SIM card interface on the external interface board uses a high-frequency optimized RGMII interface specification adapter module located at the DATA and CLK signal line inputs of the SIM card. The length equalization and impedance matching module includes serpentine traces with length equalization errors controlled within ±5mil. The power decoupling design module includes 0.1μF ceramic capacitors and 1μF tantalum capacitors, connected in parallel at the SIM card power pins. The multi-level filter bank, common-mode choke, and common ground network of the multi-interface collaborative protection and signal integrity optimization module are connected via wires with an impedance of 50Ω. These wires are used to transmit signals and ensure signal integrity.

[0085] By setting up multi-stage filter banks and common-mode chokes, common-mode noise and noise in different frequency bands are effectively eliminated, improving signal purity, reducing signal reflection, and enhancing communication reliability.

[0086] By using a multi-layer design with a shared ground network and equally spaced vias, the impedance of the ground wire is reduced, signal integrity is improved, electromagnetic interference is reduced, and the anti-interference capability of the circuit board is enhanced.

[0087] Through multi-level protection design and signal matching optimization of USB interface, Type-C interface, SIM card interface and network interface, comprehensive protection and signal integrity optimization of multiple interfaces are achieved, which improves the anti-interference ability and communication reliability of the circuit board and is suitable for applications in a variety of complex environments.

[0088] This technical solution addresses the issues of insufficient electromagnetic shielding and inadequate radiation resistance in existing tablet computers by optimizing component selection, shielding structure design, and the interlocking design between components. Its novel and rational structure, comprehensive functions, and ease of portability and operation ensure information security when processing and displaying important data, preventing information leakage and interference from external electromagnetic waves. Furthermore, the tablet computer exhibits good shock and vibration resistance and waterproofing, allowing for use in harsh environments. This technical solution overcomes many shortcomings of existing products and is particularly suitable for instruments and equipment operating in complex environments, overcoming the interference of harsh environments on product performance.

[0089] It should be noted that, for those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.

[0090] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A low-emission tablet computer, characterized in that, include: All three components—front shell, middle frame, and back cover—are capable of conducting electricity. The front shell is fixedly connected to the middle frame, and the front shell and the middle frame form a first sealed cavity; a prototype tablet computer is placed in the first sealed cavity, and the prototype tablet computer is fixedly connected to the middle frame; a touch screen is installed on the front shell at the position corresponding to the prototype tablet computer; the side of the touch screen close to the prototype tablet computer is entirely covered with an electromagnetic shielding layer; the electromagnetic shielding layer is electrically connected to the front shell through a conductive component. The middle frame is fixedly connected to the rear cover, and the middle frame and the rear cover form a second sealed cavity; the prototype tablet computer is equipped with a main control board and a drive board, and the rear cover is provided with a third sealed cavity for placing the main control board and the drive board; the third sealed cavity is located inside the second sealed cavity; The middle frame edge is provided with grooves at locations corresponding to the front shell and the rear cover; the front shell and the rear cover are provided with protrusions that correspond to and engage with the grooves; Conductive rubber strips are provided between the grooves at the edge of the middle frame corresponding to the front shell and the rear cover and the protrusions corresponding to the front shell and the rear cover. The rear cover has annular protrusions for placing the main control board and the drive board respectively; the middle frame has an isolation plate; the upper end of the annular protrusion has an annular groove for placing a conductive rubber strip; the conductive rubber strip is located between the annular protrusion and the isolation plate; the annular protrusion and the isolation plate form a third sealed cavity.

2. The low-emission tablet computer according to claim 1, characterized in that: The electromagnetic shielding layer is electromagnetic shielding glass, electromagnetic shielding mesh, or electromagnetic shielding film; the conductive component is copper foil; one end of the copper foil is attached to the electromagnetic shielding layer, and the other end is attached to the front shell.

3. The low-emission tablet computer according to claim 2, characterized in that: The middle frame has a first outlet for the circuits of the prototype tablet computer and the touch screen; the first outlet is sealed by wrapping the circuit with copper foil.

4. The low-emission tablet computer according to claim 3, characterized in that: The drive board is provided with a first conductive busbar around its perimeter; the copper foil is pasted around the first conductive busbar and overlaps with the isolation plate.

5. The low-emission tablet computer according to claim 4, characterized in that: The rear cover also houses a battery, a battery management board, and an external interface board. The annular protrusion has a second outlet for the main control board circuitry and the drive board circuitry. The second outlet is sealed by wrapping the circuitry with copper foil. The external interface board is connected to the main control board via a first shielded cable. The battery management board is connected to the external interface board via a second shielded cable. The drive board is connected to the external interface board via a third shielded cable. The battery and the battery management board are connected via a fourth shielded cable.

6. The low-emission tablet computer according to claim 5, characterized in that: The back cover has a rear camera opening at a position corresponding to the rear camera of the prototype tablet computer; an electromagnetic shielding layer is fixedly installed at the position of the rear camera opening.

7. The low-emission tablet computer according to claim 6, characterized in that: The external interface board is provided with a reserved interface for electrical connection with the prototype tablet computer and multiple external interface connectors; the rear cover is provided with multiple alignment interface openings corresponding to the multiple external interface connectors.

8. The low-emission tablet computer according to claim 7, characterized in that: It also includes communication antenna components, filters, and filtering circuits; The communication antenna assembly is fixedly installed on the outer side of the rear cover; The filter is located in the second sealed cavity and is fixedly installed on the rear cover; one end of the filter is electrically connected to the communication antenna assembly; the other end of the filter is electrically connected to the communication interface on the main control board. The filtering circuit is disposed on the external interface board and located at the rear end of the external interface connector; the filtering circuit is electrically connected to the external interface connector.

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