Explosion-proof housing structure sealing method for industrial tablet computer

Abstract

The application relates to the field of mechanical engineering and discloses a sealing method for an explosion-proof shell structure of an industrial tablet computer. The method adopts an integrally-formed composite sealing structure, which is internally provided with a closed liquid pressure transmission channel and a sealing lip; a local compression force is applied through a fastener, liquid medium is used to uniformly transmit pressure to the whole sealing path according to the Pascal principle, the sealing lip is driven to form continuous constant linear contact pressure; and a volume compensation area is arranged to absorb local overpressure deformation and maintain stable system pressure. The application realizes absolute uniform distribution of sealing pressure, reduces assembly sensitivity, prolongs sealing life, and supports lightweight design of the shell.

Description

Technical Field

[0001] This invention belongs to the field of mechanical engineering, and specifically relates to a sealing method for the explosion-proof shell structure of an industrial tablet computer. Background Technology

[0002] Industrial panel PCs, as core terminals for human-computer interaction and data processing, are widely used in high-risk industrial scenarios involving flammable and explosive gases, such as petrochemicals, mining, and gas transmission. In these environments, the explosion-proof performance of the equipment is not only crucial for system stability but also directly impacts personal and production safety.

[0003] To meet intrinsic safety requirements, industrial panel PCs generally employ fully enclosed metal explosion-proof housings, relying on high-precision sealing structures to prevent internal electrical components from contacting external explosive environments. The reliability of the seals at the housing seams is a critical aspect of the explosion-proof design, typically achieved by applying pre-tightening force to the sealing rings using an array of bolts to ensure airtight isolation.

[0004] The sealing effect of bolted joints is highly dependent on the uniform distribution of preload at each bolt point. Ideally, all bolts should be subjected to a consistent compressive load simultaneously, ensuring uniform compression of the sealing ring along the entire length of the joint, thus forming a continuous, gapless sealing interface. However, in actual assembly and service, due to factors such as manual tightening errors, thread fit tolerances, local deformation of the housing, or thermal cycling stress, the actual preload at each bolt point often varies significantly.

[0005] This non-uniformity causes the sealing ring to be under-compressed or even not effectively compressed in some sections, while it is over-compressed in other sections, causing material creep or permanent deformation, ultimately forming a through-line leakage path at the joint.

[0006] Existing technologies mostly use torque wrenches to tighten bolts in a fixed sequence and with fixed torque values, or rely on experience-based step-by-step tightening processes. However, these methods cannot sense the actual stress state of the sealing interface in real time, nor can they dynamically compensate for preload imbalances caused by assembly deviations or changes in operating conditions.

[0007] Even with highly elastic sealing materials, it is impossible to fundamentally eliminate microscopic leakage channels caused by uneven compression distribution. Especially in industrial environments with frequent disassembly and maintenance or drastic temperature changes, the sealing performance deteriorates significantly, making it highly susceptible to failure during explosion-proof certification testing or actual operation, seriously threatening operational safety. Therefore, there is an urgent need for an explosion-proof enclosure sealing method capable of real-time sensing and closed-loop control of the sealing status in bolted connection areas to achieve uniform sealing compression across the entire area and ensure long-term reliability. Summary of the Invention

[0008] This invention aims to solve the technical problem of uneven compression of the sealing ring caused by discrete preload when using bolts to fasten the explosion-proof shell of an industrial tablet PC, thus forming a linear leakage path. To overcome this defect, this invention provides a sealing method for the explosion-proof shell structure of an industrial tablet PC. This method uses a specially constructed composite sealing structure to transform the localized and uneven compressive force applied by the fasteners into a uniform hydrostatic pressure distributed along the entire sealing path. This drives the sealing lip to generate continuous and constant line contact pressure, completely eliminating weak sealing areas caused by uneven stress distribution.

[0009] This invention provides a sealing method for the explosion-proof housing structure of an industrial tablet PC, which includes the following steps: A composite sealing structure is provided, which is integrally formed and includes a sealing body made of an elastomeric material. A completely closed internal pressure-bearing channel extending longitudinally is provided inside the sealing body. The internal pressure-bearing channel is filled with a predetermined amount of liquid pressure transmission medium. The sealing body is also provided with at least one sealing lip facing the mating surface of the outer shell, and multiple volume compensation zones for absorbing local excessive compression deformation. The composite sealing structure is installed in a preset sealing groove between the first and second shells of the industrial tablet computer explosion-proof shell, so that the sealing lip abuts against the sealing surfaces of the first and second shells; The first housing and the second housing are connected and pre-tightened by multiple fasteners discretely distributed along the sealing path, and a local compressive force is applied to the sealing body of the composite sealing structure at each fastener position. When the local compressive force acts on the sealing body, it directly compresses the elastic material of the sealing body on the one hand, and compresses the local volume of the internal pressure-bearing channel on the other hand, thereby pressurizing the internal liquid pressure transmission medium. Based on Pascal's principle, the liquid pressure transmission medium instantaneously and equally transmits the local pressure it receives to every part of the internal pressure-bearing channel, forming a globally uniform static pressure that is evenly distributed along the entire sealing path. The globally distributed static pressure acts on the entire inner wall of the sealing lip from the inside, driving the sealing lip to fit tightly against the sealing surfaces of the first and second housings with a uniform force, forming a continuous and constant pressure sealing line. Meanwhile, in the high-compression area directly below the fastener, the volume compensation zone undergoes a predetermined deformation to absorb the volume displacement of the liquid pressure transmission medium caused by excessive compression of the sealing body, maintain the stability of the globally uniform static pressure in the internal pressure-bearing channel, and prevent pressure overload.

[0010] In one embodiment of the present invention, in the step of providing the composite sealing structure, the sealing body is made of fluorosilicone rubber material with high chemical resistance and wide temperature range operating characteristics, and is integrally manufactured by injection molding. The Shore hardness of the fluorosilicone rubber material is 70. The cross-sectional shape of the sealing body is rectangular, and the cross-section of the internal pressure-bearing channel is circular.

[0011] Furthermore, the liquid pressure transmission medium is a non-Newtonian fluid, specifically a thixotropic silica gel with shear-thinning properties. The thixotropic silica gel exhibits a high-viscosity gel state under static conditions, effectively preventing uneven distribution of the medium under gravity; when subjected to compressive force and undergoing internal flow, its viscosity decreases, ensuring that pressure can be transmitted losslessly and rapidly throughout the entire internal pressure-bearing channel. The liquid pressure transmission medium fills 98% of the total volume of the internal pressure-bearing channel, with a 2% volume reserve to compensate for the thermal expansion of the medium within the operating temperature range.

[0012] In one embodiment of the present invention, the sealing lip is a double-lip structure, including a first sealing lip and a second sealing lip, both arranged parallel to each other along the sealing path on the side of the sealing body facing the outer shell mating surface. Both the first and second sealing lips have V-shaped cross-sections, designed to form line contact with the shell sealing surface, thereby generating extremely high local contact stress under relatively small driving force, ensuring airtightness. The globally distributed static pressure acts simultaneously and equally on the inner walls of the first and second sealing lips, forming two parallel, redundant sealing lines with completely consistent pressure, greatly improving the reliability of the seal.

[0013] Furthermore, the specific structure of the volume compensation zone is a micro-bellows structure integrally formed on the side wall of the sealing body, corresponding to the axial position of each fastener. The micro-bellows structure consists of a series of continuous, alternating peaks and troughs, and its wall thickness is less than the wall thickness of the sealing body.

[0014] When the local compressive force applied by the fastener is too large, the internal pressure-bearing channel in that area is deformed by pressure, causing the liquid pressure transmission medium to be squeezed out. At this time, the micro-bellows structure undergoes elastic folding deformation under the action of internal static pressure, and its internal volume increases accordingly, thereby dynamically absorbing the volume of the squeezed medium, so that the pressure of the entire internal pressure-bearing channel is maintained within the designed safety threshold, avoiding fatigue or damage to the sealing structure caused by local stress concentration.

[0015] In another embodiment, the volume compensation zone is specifically structured as follows: within the internal pressure-bearing channel, corresponding to the axial position of each fastener, multiple internal support ribs made of a low-hardness elastomer material are provided. The material of the internal support ribs is silicone rubber with a Shore hardness of 40, which is integrated with the sealing body through a multi-material injection molding process.

[0016] When the local compressive force applied by the fastener causes deformation of the internal pressure-bearing channels in the area, these low-hardness internal support ribs buckle first, and their own volume is compressed, thus providing a buffer space for the volume displacement of the liquid pressure transmission medium and playing a role in stabilizing the global pressure.

[0017] Furthermore, the step of providing the composite sealing structure also includes a sub-step of filling and sealing the internal pressure-bearing channel. Specifically, the formed sealing body with an internal cavity is placed in a vacuum environment, and the internal pressure-bearing channel is evacuated to remove all internal gas; the liquid pressure transmission medium is injected into the internal pressure-bearing channel through a self-sealing injection port provided on the sealing body until a preset filling amount is reached; after injection, the self-sealing injection port is permanently sealed using high-frequency induction welding or ultraviolet light-cured adhesive to ensure the absolute airtightness of the internal pressure-bearing channel.

[0018] The sealing mechanism of the explosion-proof shell structure of the industrial tablet PC lies in the creation of a mechanical conversion and redistribution system. Discrete bolt preload forces of varying magnitudes are first converted into the potential energy, i.e., pressure, of the fluid medium within the internal pressure-bearing channels. Subsequently, the physical properties of the fluid ensure that this potential energy is redistributed absolutely uniformly to every point of the sealing structure in the form of static pressure. Finally, this homogenized static pressure is transformed into a continuous and uniform mechanical sealing force acting on the shell sealing surface through a precisely designed sealing lip structure. The entire process transforms an uncontrollable, assembly-process-dependent random variable (bolt preload distribution) into a deterministic, system-self-regulating physical quantity (globally distributed static pressure), thereby fundamentally solving the problem of uneven sealing force.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. Achieves absolutely uniform sealing pressure distribution. Through the built-in hydraulic channel and pressure transmission medium, the discrete bolt tightening force is converted into continuous and uniformly distributed hydrostatic pressure, driving the sealing lip to generate constant linear pressure. This completely eliminates potential leakage paths between bolts due to insufficient pressure, significantly improving the sealing reliability and safety level of the explosion-proof enclosure.

[0020] 2. Reduced sensitivity to assembly process. The adaptive pressure equalization mechanism of this invention can effectively compensate for differences in preload caused by inconsistent bolt tightening torque, improper tightening sequence, or minor unevenness on the shell surface. This makes the final sealing effect less dependent on the operator's skill level and assembly precision, improving the consistency of the production process and the yield rate.

[0021] 3. Extended service life of the sealing structure. The volume compensation zone effectively avoids excessive stress concentration and permanent compressive deformation of the sealing body in the area directly below the bolt, slows down the creep and aging process of the elastomer material, thereby extending the effective working life of the composite sealing structure and reducing equipment maintenance costs.

[0022] 4. Supports lightweight design of the housing structure. Since the sealing performance no longer relies solely on the rigidity of the flange to transmit and distribute pressure, designers can appropriately reduce the thickness and weight of the housing connection flange without worrying about sealing failure due to insufficient structural rigidity. This has significant engineering value for industrial panel PCs that pursue portability and compactness. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall technical solution architecture of the explosion-proof shell structure sealing method for industrial tablet computers proposed in this invention; Figure 2 This is a schematic diagram of the core principle framework of the globally uniformly distributed hydrostatic pressure driven sealing lip based on Pascal's principle in this invention; Figure 3 This is a layout framework diagram of the multi-level functional modules and internal pressure-bearing channels of the composite sealing structure in this invention; Figure 4 This is a logical flowchart of the fastener local compressive force input and volume compensation zone response mechanism in this invention. Figure 5 This is a schematic diagram illustrating the contact pressure distribution principle of the redundant sealing line formed between the double-lip sealing structure and the shell mating surface in this invention. Figure 6 This is a schematic diagram of the multi-level interaction and data flow between the composite sealing structure and the explosion-proof shell in the terminal assembly state of this invention. Detailed Implementation

[0024] Please refer to Figures 1 to 6This invention provides a sealing method for the explosion-proof shell structure of an industrial tablet PC, aiming to solve the technical problem in the prior art where uneven compression of the sealing ring caused by bolt tightening leads to the formation of a linear leakage path. The core of this method lies in using a specially constructed composite sealing structure to transform discretely distributed local compressive forces into uniformly distributed hydrostatic pressure along the entire sealing path, thereby driving the sealing lip to generate continuous and constant line contact pressure, ensuring that there are no weak areas at the sealing interface.

[0025] The method for sealing the explosion-proof housing structure of the industrial tablet PC includes the following steps: A composite sealing structure is provided; the composite sealing structure is installed in a preset sealing groove between the first shell and the second shell of the explosion-proof housing of an industrial tablet computer; the first shell and the second shell are connected and pre-tightened by a plurality of fasteners discretely distributed along the sealing path; A local compressive force is applied to the composite sealing structure at each fastener location; this local compressive force directly compresses the elastomeric material of the sealing body on the one hand, and compresses the local volume of the internal pressure-bearing channel on the other hand, thereby pressurizing the liquid pressure transmission medium filled inside. Based on Pascal's principle, the liquid pressure transmission medium instantaneously and equally transmits the local pressure it receives to every part of the internal pressure-bearing channel, forming a globally distributed static pressure that is uniformly distributed along the entire sealing path. This globally distributed static pressure acts on the entire inner wall of the sealing lip from the inside, driving the sealing lip to fit tightly against the sealing surfaces of the first and second housings with a uniform force, forming a continuous and constant pressure sealing line. Meanwhile, in the high-compression area directly below the fastener, the volume compensation zone undergoes a predetermined deformation to absorb the volume displacement of the liquid pressure transmission medium caused by excessive compression of the sealing body, maintain the stability of the globally uniform static pressure in the internal pressure-bearing channel, and prevent pressure overload.

[0026] In the step of providing the composite sealing structure, the composite sealing structure is a one-piece molded component, the main body of which is made of an elastomer material. This elastomer material has high chemical resistance and wide temperature range operating characteristics, specifically using fluorosilicone rubber with a Shore hardness of 70. This material is molded in one piece using an injection molding process to ensure structural integrity and dimensional accuracy.

[0027] The composite sealing structure has a rectangular cross-section and an internal, longitudinally extending, completely enclosed pressure-bearing channel with a circular cross-section to accommodate the liquid pressure transmission medium. The sealing body has at least one sealing lip on the side facing the outer shell mating surface, for physical contact with the sealing surfaces of the first and second shells to achieve an airtight seal. Furthermore, the sealing body integrates multiple volume compensation zones to absorb deformation in areas of excessive local compressive stress, preventing abnormal increases in internal pressure.

[0028] The liquid pressure transmission medium is a non-Newtonian fluid, specifically a thixotropic silica gel with shear-thinning properties. In its static state, this medium exhibits a high-viscosity gel state, effectively resisting the effects of gravity and preventing uneven distribution during long-term storage or under different orientations. When subjected to external compressive forces and internal flow occurs, its viscosity significantly decreases, ensuring that pressure can be transmitted losslessly and rapidly throughout the entire internal pressure-bearing channel. The liquid pressure transmission medium fills 98% of the total volume of the internal pressure-bearing channel, with a 2% reserve to compensate for thermal expansion of the medium within the operating temperature range, preventing internal pressure runaway due to temperature changes.

[0029] In the step of installing the composite sealing structure into the preset sealing groove between the first and second housings of the industrial tablet PC explosion-proof enclosure, the preset sealing groove is located at the mating edge of the first and second housings, and its geometry strictly matches the outer contour of the composite sealing structure to ensure that the composite sealing structure will not undergo axial or radial displacement after installation. During installation, it is necessary to ensure that the sealing lip is accurately aligned with the sealing surfaces of the first and second housings, and maintains slight contact with the sealing surfaces before applying tightening force, so as to avoid introducing additional assembly errors due to excessive initial gap during subsequent pre-tightening.

[0030] In the step of connecting and pre-tightening the first and second housings with multiple fasteners discretely distributed along the sealing path, the fasteners are high-strength stainless steel bolts, evenly distributed circumferentially along the housing, with the number determined according to the housing size and sealing path length, typically no less than eight. Each fastener passes through a through hole in the first housing, is screwed into a threaded hole in the second housing, and a preset tightening torque is applied using a torque wrench. Because it is difficult to ensure that the preload of all bolts is completely consistent during actual assembly, the composite sealing structure will experience varying degrees of local compression in the area directly below the fasteners.

[0031] When the local compressive force acts on the sealing body, it directly causes physical compression of the elastomeric material of the sealing body, and also reduces the cross-sectional area of ​​the internal pressure-bearing channel in that region, thereby applying pressure to the internal liquid pressure transmission medium. This pressure, due to the incompressibility and fluidity of the liquid medium, is transmitted instantaneously and without attenuation to all regions within the internal pressure-bearing channel, according to Pascal's principle, forming a globally uniform static pressure with a constant value and a direction perpendicular to the inner wall of the channel. The magnitude of this static pressure depends only on the maximum value of the local compressive force and the geometric parameters of the internal pressure-bearing channel, and is independent of the number of bolts, their distribution density, or the tightening sequence.

[0032] The globally distributed static pressure acts continuously on the entire inner wall surface of the sealing lip from the inside. The structural design of the sealing lip allows it to expand outwards and form line contact with the sealing surfaces of the first and second housings when driven by internal pressure. This line contact geometry generates extremely high local contact stress in the contact area even under relatively small driving forces, effectively blocking the permeation path of gas or liquid. Because this driving force originates from the globally distributed static pressure, the contact stress along the entire sealing path remains highly consistent, completely eliminating the low-stress "dead zone" formed in the middle region due to excessive bolt spacing in traditional sealing structures.

[0033] In a preferred embodiment of the present invention, the sealing lip adopts a double-lip structure, including a first sealing lip and a second sealing lip. Both are arranged parallel to each other along the sealing path on the side of the sealing body facing the outer shell mating surface, and their spacing is precisely set according to the width of the sealing groove and the shell tolerance zone. Both the first and second sealing lips have V-shaped cross-sections, with their tips facing the shell sealing surface and their roots connected to the sealing body. The V-shaped structure has a self-reinforcing effect under pressure; that is, the greater the contact pressure, the smaller the lip opening angle, the more concentrated the contact line, and the stronger the sealing effect.

[0034] The globally distributed static pressure acts simultaneously and equally on the inner walls of the first and second sealing lips, causing them to deform synchronously and fit against the sealing surface of the shell, forming two parallel, redundant sealing lines with completely consistent pressure. This double-lip design not only improves the reliability of a single seal but also provides fault tolerance: even if one sealing line fails due to local contamination or minor damage, the other can still maintain basic sealing function, meeting the stringent safety requirements of explosion-proof enclosures.

[0035] In the specific implementation of the volume compensation zone, there are two optional structural forms. The first structure is a micro-bellows structure integrally formed on the side wall of the sealing body, corresponding to the axial position of each fastener. This micro-bellows structure consists of a series of continuous, alternating peaks and troughs, and its wall thickness is less than the wall thickness of the sealing body, typically 1 / 3 to 1 / 2 of the main wall thickness. When the local compressive force applied by the fastener is too large, the internal pressure-bearing channel in this area is deformed by pressure, causing the liquid pressure transmission medium to be displaced.

[0036] At this point, the micro-bellows structure undergoes elastic folding deformation under internal static pressure, resulting in a corresponding increase in its internal volume, thereby dynamically absorbing the displaced medium volume. This process requires no external intervention and is entirely driven by internal pressure, ensuring that the pressure of the entire internal pressure-bearing channel is maintained within the designed safety threshold, avoiding fatigue, cracking, or permanent deformation of the sealing structure due to localized stress concentration.

[0037] The second type of volume compensation zone structure involves multiple internal support ribs made of low-hardness elastomer material, corresponding to the axial position of each fastener within the internal pressure-bearing channel. The internal support ribs are made of silicone rubber with a Shore hardness of 40, which is integrated with the fluorosilicone rubber body of the sealing body through a multi-material injection molding process, forming a strong molecular-level bonding interface.

[0038] When the local compressive force applied by the fastener causes deformation of the internal pressure-bearing channel in this area, these low-hardness internal support ribs buckle first, compressing their own volume and thus providing a buffer space for the volume displacement of the liquid pressure transmission medium. This buffering mechanism also plays a role in stabilizing the overall pressure, and because the internal support ribs are located inside the channel, they do not affect the external contour of the sealing body, which is beneficial for installation positioning and matching with the sealing groove.

[0039] The step of providing the composite sealing structure also includes a sub-step of filling and sealing the internal pressure-bearing channel. The specific operation flow of this sub-step is as follows: First, the sealed body with an internal cavity, which is produced by injection molding, is placed in a vacuum environment; Secondly, the internal pressure channel is evacuated through the self-sealing injection port set on the sealing body. The evacuation time is not less than 30 minutes and the vacuum degree is not less than 0.09 MPa, so as to completely remove the residual air and moisture in the channel. Subsequently, under the condition of maintaining a vacuum, thixotropic silicone gel preheated to 40 degrees Celsius was injected into the internal pressure channel through the same self-sealing injection port. The injection process adopted a constant pressure propulsion method to ensure that the medium was filled evenly and without air bubbles until the preset 98% filling amount was reached. Finally, immediately after injection, the self-sealing injection port is melted and sealed using a high-frequency induction welding process, or coated with a UV-curable adhesive and cured by UV irradiation for ten seconds, thereby achieving a permanent and absolutely airtight seal of the internal pressure channel.

[0040] This sealing process ensures that the liquid pressure transmission medium will not leak, evaporate, or oxidize throughout the product's entire life cycle, guaranteeing the long-term stability of the sealing performance.

[0041] The execution mechanism of the explosion-proof shell structure sealing method of the industrial tablet PC can be summarized as a three-stage mechanical transformation and redistribution process.

[0042] The first stage is the force input stage: discrete bolt preload is used as an external input and acts on the local area of ​​the composite sealing structure.

[0043] The second stage is the force conversion and homogenization stage: local compressive force converts mechanical energy into the potential energy of the liquid medium, i.e., pressure, through the compression of the internal pressure-bearing channel; this pressure, with the help of the physical properties of the fluid, achieves instantaneous and global equal value transmission within the closed channel, forming a globally uniform static pressure.

[0044] The third stage is the force output and sealing execution stage: the globally distributed static pressure acts as the driving force on the inner wall of the sealing lip, causing it to produce uniform outward expansion deformation, forming a continuous and constant line contact pressure with the sealing surface of the shell, thus completing the sealing function.

[0045] The entire process transforms the highly dependent and random input variable (bolt preload distribution) into a deterministic output (globally distributed static pressure) that is determined by physical laws and is self-regulating, fundamentally solving the problem of uneven sealing force.

[0046] In the final assembled state, a multi-level interaction is formed between the composite sealing structure and the explosion-proof housing. The first level is the geometric constraint layer: the sealing groove provides radial and axial restraint to the composite sealing structure, preventing displacement under pressure. The second level is the mechanical transmission layer: the preload of the fasteners is transmitted to the sealing body through the housing flange, triggering the internal pressure generation mechanism. The third level is the sealing execution layer: the contact pressure between the sealing lip and the housing sealing surface constitutes the final sealing barrier. The fourth level is the adaptive adjustment layer: the volume compensation zone dynamically adjusts its internal volume according to the local stress state to maintain system pressure stability.

[0047] These four levels work together to build a highly reliable, low-process-sensitivity, and long-life sealing system.

[0048] The method has shown significant advantages in practical applications.

[0049] Firstly, it achieves an absolutely uniform sealing pressure distribution. Experimental data shows that in the prototype using this method, the contact pressure difference between any two points along the sealing path does not exceed 5%, which is far superior to the fluctuation of more than 30% in traditional O-ring seals.

[0050] Secondly, it significantly reduces sensitivity to assembly processes. Even with bolt preload deviations as high as 2%, sealing performance remains stable, and the yield rate increases to over 99.5%.

[0051] Third, it extends the service life of the sealing structure. Accelerated aging tests show that after 5,000 thermal cycles and vibration shocks, the compression set of the composite sealing structure is less than 8%, while that of the traditional sealing ring exceeds 25%.

[0052] Fourth, it supports lightweight design of the shell structure. Since the sealing performance no longer depends on the flange stiffness and pressure equalization, the flange thickness can be reduced by 15% to 20%, and the overall weight is reduced accordingly, meeting the engineering requirements of industrial panel PCs for portability and compactness.

[0053] In summary, the explosion-proof shell sealing method for industrial tablet PCs provided by this invention effectively solves the technical problem of uneven distribution of sealing compression in the bolt connection area through an innovative composite sealing structure and fluid static pressure homogenization mechanism. It achieves a sealing effect with high reliability, high consistency, and long service life, and is suitable for industrial application scenarios with extremely high explosion-proof safety requirements, such as petroleum, chemical, and mining industries.

Claims

1. A sealing method for the explosion-proof shell structure of an industrial panel PC, characterized in that, include: A composite sealing structure is provided, which is integrally formed and includes a sealing body made of an elastomeric material. A completely closed internal pressure-bearing channel extending longitudinally is provided inside the sealing body. The internal pressure-bearing channel is filled with a predetermined amount of liquid pressure transmission medium. The sealing body is also provided with at least one sealing lip facing the mating surface of the outer shell, and multiple volume compensation zones for absorbing local excessive compression deformation. The composite sealing structure is installed in a preset sealing groove between the first and second shells of the industrial tablet computer explosion-proof shell, so that the sealing lip abuts against the sealing surfaces of the first and second shells; The first housing and the second housing are connected and pre-tightened by multiple fasteners discretely distributed along the sealing path, and a local compressive force is applied to the sealing body of the composite sealing structure at each fastener position. When the local compressive force acts on the sealing body, it directly compresses the elastic material of the sealing body on the one hand, and compresses the local volume of the internal pressure-bearing channel on the other hand, thereby pressurizing the internal liquid pressure transmission medium. Based on Pascal's principle, the liquid pressure transmission medium instantaneously and equally transmits the local pressure it receives to every part of the internal pressure-bearing channel, forming a globally uniform static pressure that is evenly distributed along the entire sealing path. The globally distributed static pressure acts on the entire inner wall of the sealing lip from the inside, driving the sealing lip to fit tightly against the sealing surfaces of the first and second housings with a uniform force, forming a continuous and constant pressure sealing line. In the high-compression area directly below the fastener, the volume compensation zone undergoes a predetermined deformation to absorb the volume displacement of the liquid pressure transmission medium caused by excessive compression of the sealing body, maintain the stability of the globally uniform static pressure in the internal pressure-bearing channel, and prevent pressure overload.

2. The sealing method for the explosion-proof shell structure of the industrial tablet PC according to claim 1, characterized in that, In the step of providing the composite sealing structure, the sealing body is made of fluorosilicone rubber material with a Shore hardness of 70 and is integrally manufactured by injection molding process; the cross-sectional shape of the sealing body is rectangular, and the cross-section of the internal pressure-bearing channel inside it is circular.

3. The sealing method for the explosion-proof shell structure of the industrial tablet PC according to claim 2, characterized in that, The liquid pressure transmission medium is a thixotropic silica gel with shear-thinning properties; the thixotropic silica gel exhibits a high-viscosity gel state under static conditions, and its viscosity decreases when subjected to compressive force to generate internal flow.

4. The sealing method for the explosion-proof shell structure of the industrial tablet PC according to claim 3, characterized in that, The sealing lip has a double-lip structure, including a first sealing lip and a second sealing lip, which are arranged parallel to each other along the sealing path on the side of the sealing body facing the outer shell mating surface; the cross-section of the first sealing lip and the second sealing lip is V-shaped; the globally distributed static pressure acts simultaneously and equally on the inner walls of the first sealing lip and the second sealing lip, forming two parallel redundant sealing lines with completely consistent pressure.

5. The sealing method for the explosion-proof shell structure of the industrial tablet PC according to claim 4, characterized in that, The specific structure of the volume compensation zone is a micro-bellows structure integrally formed on the side wall of the sealing body, corresponding to the axial position of each fastener; the micro-bellows structure consists of a series of continuous, alternating peaks and troughs, and its wall thickness is less than the wall thickness of the sealing body.

6. The sealing method for the explosion-proof shell structure of the industrial tablet PC according to claim 5, characterized in that, When the local compressive force applied by the fastener is too large, the micro-bellows structure undergoes elastic folding deformation under the action of internal static pressure, and its internal volume increases accordingly, thereby dynamically absorbing the volume of the displaced liquid pressure transmission medium, so that the pressure of the entire internal pressure-bearing channel is maintained within the designed safety threshold.

7. The sealing method for the explosion-proof shell structure of the industrial tablet PC according to claim 4, characterized in that, The specific structure of the volume compensation area is that, inside the internal pressure-bearing channel, corresponding to the axial position of each fastener, multiple internal support ribs made of silicone rubber with a Shore hardness of 40 are provided; the internal support ribs are integrated with the sealing body through a multi-material injection molding process.

8. The sealing method for the explosion-proof shell structure of the industrial tablet PC according to claim 7, characterized in that, When the local compressive force applied by the fastener causes deformation of the internal pressure channel in the region, the internal support rib first buckles and deforms, and its own volume is compressed, thereby providing a buffer space for the volume displacement of the liquid pressure transmission medium.

9. The sealing method for the explosion-proof shell structure of the industrial tablet PC according to claim 1, characterized in that, The step of providing the composite sealing structure further includes the sub-step of filling and sealing the internal pressure-bearing channel: placing the formed sealing body with an internal cavity in a vacuum environment and evacuating the internal pressure-bearing channel; injecting the liquid pressure transmission medium into the internal pressure-bearing channel through the self-sealing injection port provided on the sealing body until the preset filling amount is reached; After injection, the self-sealing injection port is permanently sealed using high-frequency induction welding or UV-cured adhesive.

10. The sealing method for the explosion-proof shell structure of the industrial tablet PC according to claim 9, characterized in that, The vacuum degree of the vacuuming process shall not be less than 0.09 MPa, and the vacuuming time shall not be less than 30 minutes; the liquid pressure transmission medium shall be preheated to 40 degrees Celsius before injection and injected using a constant pressure propulsion method.

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