An explosion-proof membrane component

Abstract

The present application provides an explosion-proof membrane assembly, which includes an elastic membrane and a waterproof and breathable membrane. The thickness T0 of the elastic membrane is 10-500 μm. The outer edge of one side surface of the elastic membrane is bonded with a first adhesive layer. The elastic membrane includes a deformation zone located radially inward of the first adhesive layer and a bonding zone corresponding to the first adhesive layer. The outer edge of the surface of the elastic membrane on the side away from the first adhesive layer is bonded with an anti-detachment ring through a second adhesive layer. The hardness of the anti-detachment ring is higher than that of the elastic membrane. The inner diameter D1 of the anti-detachment ring and the inner diameter D2 of the first adhesive layer satisfy |D1-D2| / D2 is not greater than 0.3. The combination of the elastic membrane and the waterproof breathable membrane achieves the requirements of air permeability and balanced internal and external pressure difference under normal working conditions. The elastic membrane meets the design requirements of high explosion pressure difference and rapid pressure relief. The inner diameter D1 of the anti-detachment ring and the inner diameter D2 of the first adhesive layer satisfy |D1-D2| / D2 is not greater than 0.3, so that the outer ring of the anti-detachment ring, the second adhesive layer, and the elastic membrane are bonded to form a rigid body, which improves the deformation uniformity of the deformation zone and solves the problem of separation of the bonding zone and the first adhesive layer.

Description

Technical Field

[0001] The invention relates to the field of explosion-proof technology, and in particular to an explosion-proof membrane component. Background Art

[0002] An explosion-proof valve is a pressure relief device used for equipment or pipelines containing flammable gases or flammable substances in dust-proof systems. In new energy vehicles, the battery pack is a vital component, and the use of the battery pack will generate heat, causing the internal air pressure of the battery pack to increase. When the temperature of the battery pack rises abnormally quickly, the internal air pressure will also rise rapidly, which may cause damage to internal components or even exceed the designed sealing capacity of the battery pack and cause an explosion. In order to prevent the internal air pressure of the battery pack from being too high, an explosion-proof valve is usually installed on the battery pack to maintain the balance of internal and external air pressure. When the air pressure in the battery pack increases sharply, the breathable membrane in the explosion-proof valve will deform, and when the air pressure reaches the preset limit value, the breathable membrane inside the explosion-proof valve will rupture, quickly balancing the internal and external air pressures to achieve the purpose of pressure relief.

[0003] The Chinese utility model patent with the authorization announcement number CN218648096U discloses an explosion-proof valve, wherein the explosion-proof valve includes a valve cover and a valve body that can be engaged with each other; a waterproof breathable membrane is arranged in the pressure relief channel of the valve body, and the waterproof breathable membrane is a PTFE microporous membrane; a piercing piece with a sharp portion facing the waterproof breathable membrane is arranged on the valve cover, and the fixed portion of the piercing piece is arranged on the valve cover, and a notch is opened on the sharp portion of the piercing piece to form multiple pointed portions. The microporous structure in the PTFE microporous membrane meets the ventilation requirements during normal use, and when the pressure difference reaches the preset limit value, the PTFE microporous membrane that bulges to a certain height is pierced by the piercing piece to achieve the pressure relief effect.

[0004] Under normal working conditions, the PTFE membrane of equipment such as battery packs plays a waterproof and breathable role to prevent water from entering the battery pack. At the same time, to balance the pressure inside and outside the equipment, it must be able to provide a certain amount of air permeability. The designed bursting pressure difference of the explosion-proof valve is 5-15kPa. Considering the relatively poor deformation ability of the PTFE membrane itself and the need for product miniaturization, the distance between the PTFE membrane and the puncture piece is relatively small. In order to allow the PTFE membrane to produce a certain deformation under a small pressure difference, the density and / or thickness of the PTFE membrane should not be too large, that is, the strength cannot be too high, otherwise a sufficiently large breach cannot be formed during the explosion, and the pressure cannot be quickly released.

[0005] However, when the user's bursting pressure differential design value is relatively high, for example, the bursting pressure differential design value is 16-100kPa, that is, to increase the bursting pressure differential of the above-mentioned explosion-proof valve, the membrane must burst under a higher pressure differential. One of the improvement directions is to increase the distance between the PTFE membrane and the puncture piece. However, increasing the distance between the PTFE membrane and the puncture piece is not conducive to the miniaturization of the product. Moreover, because the deformation ability of the PTFE membrane itself is relatively poor, more importantly, after increasing the distance between the PTFE membrane and the puncture piece, the bursting stability is difficult to guarantee. Moreover, after increasing the distance between the PTFE membrane and the puncture piece, it is more difficult to form a large rupture when the PTFE membrane is punctured. Therefore, increasing the distance between the PTFE membrane and the puncture piece is not an effective improvement method, and it is impossible to achieve stable and rapid pressure relief under high bursting pressure differentials.

[0006] The second improvement direction is to increase the burst pressure difference by reducing the effective area of ​​the membrane. However, for PTFE membrane, this technical means still cannot meet the high burst design requirements for the following reasons:

[0007] For the membrane of the same material, according to Hooke's law, σ=Eε, where σ represents stress, which indicates the internal force per unit area, strain ε=ΔS / S, which is a dimensionless parameter, ΔS=εS is the deformation variable, and E represents the elastic modulus. For the waterproof breathable membrane, ΔS is the product of strain ε and effective area S, and stress σ is equivalent to the internal and external pressure difference P. When the internal and external pressure difference P increases, that is, stress σ increases, and the elastic modulus E remains unchanged, the strain ε increases. Under the condition of increasing strain ε, if the effective area S of the membrane remains unchanged, the deformation variable ΔS becomes larger. Under the condition that the distance between the waterproof breathable membrane and the puncture piece remains unchanged, the membrane will be punctured by the puncture piece before the internal and external pressure difference reaches the preset value of the bursting pressure difference. Therefore, under the premise of keeping the elastic modulus of the waterproof breathable membrane and the distance between the waterproof breathable membrane and the puncture piece constant, in order to ensure that it can provide a higher bursting pressure difference, the area of ​​the effective area of ​​the waterproof breathable membrane must be reduced.

[0008] With the trend of product miniaturization, the original size of the explosion-proof valve used in the battery pack is relatively small, that is, the original size of the PTFE membrane is relatively small, and the area S of the effective area can be further reduced to a limited extent. In addition, the mechanical properties of the PTFE membrane make the breach formed when it is punctured by the puncture piece not large. If the area of ​​the effective area of ​​the membrane is designed to be very small in order to meet the design value of the high burst pressure difference, that is, the size of the membrane is greatly reduced, the breach formed after the small-sized PTFE membrane is punctured by the puncture piece will be even smaller, further aggravating the problem of insufficient pressure relief and making it difficult to relieve pressure quickly. Moreover, the high burst pressure difference design condition places higher requirements on the pressure relief capacity under the burst pressure difference, because more gas needs to be discharged in a very short time, that is, more gas needs to be discharged from a smaller breach in a very short time, which is almost impossible to achieve.

[0009] In other words, reducing the effective area of ​​the PTFE membrane cannot achieve stable and rapid pressure relief under high burst pressure differences.

[0010] In addition, if the bursting pressure difference of the PTFE membrane is increased by increasing its elastic modulus, that is, its strength, a similar problem also exists, that is, the high-strength PTFE membrane is not easy to be punctured, or even if it can be punctured, the resulting rupture is smaller and the purpose of rapid pressure relief cannot be achieved.

[0011] In summary, for the existing explosion-proof valve with a single PTFE membrane, it is impossible to achieve both a high burst pressure difference design value and stable and rapid pressure relief under a high burst pressure difference. Summary of the invention

[0012] This application is proposed to solve the problem that the existing explosion-proof valve containing PTFE membrane cannot take into account both the high burst pressure difference design value and the stable and rapid pressure relief under the high burst pressure difference. This application provides an explosion-proof membrane assembly, and the specific scheme is as follows:

[0013] An explosion-proof membrane assembly, comprising an elastic membrane and a waterproof breathable membrane, wherein the thickness T0 of the elastic membrane is 10-500 μm, an annular first adhesive layer is bonded to the outer edge of the axial side surface of the elastic membrane, and the elastic membrane comprises a deformation zone located radially inside the first adhesive layer and an adhesive zone corresponding to the first adhesive layer;

[0014] The outer edge of the elastic membrane surface facing away from the first adhesive layer is bonded with an anti-detachment ring through an annular second adhesive layer. The hardness of the anti-detachment ring is higher than that of the elastic membrane. The inner diameter D1 of the anti-detachment ring and the inner diameter D2 of the first adhesive layer satisfy |D1-D2| / D2 is not greater than 0.3.

[0015] The explosion-proof membrane assembly provided by the present application includes an elastic membrane and a waterproof breathable membrane, and the explosion-proof membrane assembly is installed at the opening of the shell of a device (such as a battery pack). Specifically: the inner edge of the waterproof breathable membrane is bonded to the surface of the first adhesive layer facing away from the elastic membrane, so that the elastic membrane and the waterproof breathable membrane form a whole, and the whole is then bonded to the opening of the shell through the adhesive layer located on the side of the waterproof breathable membrane facing away from the first adhesive layer; or, the elastic membrane is directly bonded to an opening of the shell through the first adhesive layer, and the waterproof breathable membrane is bonded to another opening of the shell through another adhesive layer, that is, the elastic membrane and the waterproof breathable membrane are installed independently but used in combination, and can still be considered to belong to the same explosion-proof membrane assembly, wherein the bonding positions of the elastic membrane and the waterproof breathable membrane can be very close or very far away.

[0016] The waterproof breathable membrane is used to meet the requirements of air permeability and balance the internal and external pressure difference under normal working conditions. Since the changes in internal and external air pressure under normal working conditions are relatively small, the requirements for air permeability are not high. A waterproof breathable membrane with a smaller area can be selected to better meet the needs of miniaturization. The elastic modulus of the elastic membrane is lower and the deformation ability is better. The thickness is selected in the range of 10-500μm. It is very convenient to reasonably adjust the size of its deformation zone under the premise of meeting the user's overall size requirements. It is easy to obtain an explosion-proof membrane component with a bursting pressure difference of 16-100kPa, which meets the design value requirements of high bursting pressure difference. Moreover, it is precisely because the elastic modulus of the elastic membrane is small that when the pressure difference reaches the bursting pressure difference, the deformation of the elastic membrane is much greater than that of the PTFE microporous membrane, and it is easy to form a large rupture during the explosion, thereby realizing a rapid pressure relief function.

[0017] Even if the area of ​​the deformation zone of the elastic membrane is reduced in order to meet the high burst pressure difference design value or to meet the miniaturization requirements, since the deformation zone is easy to form a large rupture, it can still ensure rapid pressure relief, achieving both the high burst pressure difference design value and the rapid pressure relief function under high burst pressure difference. Moreover, since the elastic modulus of the elastic membrane is low, it can burst by itself after a sufficiently large deformation, omitting the piercing piece, greatly simplifying the structure, and there is no need to consider the problem of the product size being too large due to the setting of the piercing piece, while also significantly reducing the user's cost.

[0018] After the elastic membrane is installed by bonding the first adhesive layer, it is affected by factors such as edge deformation after die-cutting of the adhesive layer and glue overflow. The weak bonding point is often the junction of the deformation zone and the bonding zone. The larger deformation of the elastic membrane under the same pressure difference means that the junction also has a greater deformation tendency. The above two factors together lead to the problem of uneven bonding strength at the inner boundary of the bonding zone, which in turn leads to uneven circumferential deformation capacity of the outer edge of the deformation zone. The deformation process is naturally affected, and ultimately leads to unstable burst pressure difference of the membrane assembly. For high burst pressure difference application conditions, high stability of the burst pressure difference is essential to ensure equipment safety.

[0019] An anti-detachment ring is fixed to the outer edge of the surface of the elastic membrane on the side away from the first adhesive layer through the second adhesive layer, and the inner diameter D1 of the anti-detachment ring and the inner diameter D2 of the first adhesive layer satisfy |D1-D2| / D2 is not greater than 0.3, the inner boundary of the first adhesive layer forms the boundary between the deformation zone and the bonding zone of the elastic membrane, and the inner diameter of the first adhesive layer is exactly the diameter of the deformation zone, that is, the distance between the inner boundary of the anti-detachment ring and the outer boundary of the deformation zone is not greater than 30% of the diameter of the deformation zone, and the anti-detachment ring is connected to the outer ring of the elastic membrane (the outer ring may only include the bonding zone or include the outer ring of the bonding zone and the deformation zone) through the second adhesive layer. Since the hardness of the anti-detachment ring is higher than that of the elastic membrane, the anti-detachment ring and the first adhesive layer are not less than 0.3. The overall stiffness of the area where the two adhesive layers and the outer ring of the elastic membrane are bonded together is relatively high. In addition, the hard anti-detachment ring often has a more uniform overall rigidity, which can greatly avoid the possibility of uneven deformation caused by uneven bonding force at the boundary between the deformation zone and the bonding zone. That is, the setting of the anti-detachment ring and the second adhesive layer improves the bonding strength at the inner boundary of the bonding zone, that is, the uniformity of the fixing effect. Then, the deformation of the deformation zone after being subjected to the pressure difference is relatively regular and stable, that is, the deformation uniformity of the deformation zone is improved. Accordingly, as long as the configuration of the membrane assembly is certain, the deformation zone of the elastic membrane will explode near the design value of the bursting pressure difference, thereby ensuring the explosion stability of the membrane assembly.

[0020] The inventors of the present application unexpectedly discovered that, after a detachment-blocking ring is fixed to the outer edge of the surface of the elastic membrane on the side away from the first adhesive layer through the second adhesive layer, and the inner diameter D1 of the detachment-blocking ring and the inner diameter D2 of the first adhesive layer satisfy |D1-D2| / D2 not greater than 0.3, during the long-term use of the membrane assembly, not only does it have good blasting stability, but it also solves the problem of easy detachment of the bonding area and the first adhesive layer due to the introduction of the elastic membrane into the membrane assembly.

[0021] Since the elastic film is deformed more under a certain pressure difference, its deformation zone bulges higher in the direction away from the first adhesive layer. At this time, not only the deformation zone will be greatly deformed, but also the inner boundary of the bonding zone will be greatly deformed or have a greater deformation tendency, which naturally has a higher possibility of peeling, while the radial outer side of the inner boundary of the bonding zone (or called the outer ring area) is less affected, has a smaller deformation or deformation tendency, and naturally has a lower possibility of peeling, which means that the peeling possibility of the area near the inner boundary of the bonding zone is different from that of the outer ring area. Among them, the area near the inner boundary of the bonding zone and the corresponding area of ​​the first adhesive layer need to resist a greater deformation or deformation tendency, and the inner boundary of the bonding zone can easily form the starting point for the local separation of the bonding zone and the first adhesive layer, while the outer ring area of ​​the bonding zone almost does not need to resist deformation or deformation tendency, so the first adhesive layer at this location cannot inhibit or control the local separation of its inner boundary. Only when the inner boundary of the bonding area peels off, causing the deformation or deformation trend to move radially outward, does the bonding effect between the outer ring area and the first adhesive layer begin to resist the deformation or deformation trend. In other words, although the bonding area has a certain width, the large deformation of the elastic film under the pressure difference makes it so that only the area near the inner boundary of the bonding area and the corresponding area of ​​the first adhesive layer play an anti-peeling role. This local anti-peeling method is naturally more likely to cause peeling. Then, as the deformation area gradually bulges, the separation of the bonding area and the first adhesive layer will start from the inner boundary of the first adhesive layer and gradually spread outward until the bonding area and the first adhesive layer are completely separated. Therefore, in actual use, the probability of the bonding area and the first adhesive layer being completely separated is very high, that is, the problem that the deformation area has not exploded yet, but the bonding area has been completely separated from the first adhesive layer often occurs. That is to say, while introducing the elastic membrane to meet the design requirements of high burst pressure difference and the requirements of stable and rapid pressure relief under high burst pressure difference, it is also necessary to consider the problem of separation of the bonding area of ​​the elastic membrane and the first adhesive layer caused by the large deformation due to the low elastic modulus of the elastic membrane. Once the two are separated, the entire membrane assembly will fail.

[0022] It should be noted that the PTFE microporous membrane has a large elastic modulus and a small deformation amount under pressure. The deformation or deformation trend of the bonding area, whether it is the inner boundary or the outer circle area, is slightly different, so there is no problem of detachment between the PTFE microporous membrane and the adhesive layer.

[0023] The setting of the anti-detachment ring not only ensures the stability of the burst pressure difference, but also solves the problem of the elastic film's bonding area and the first adhesive layer being separated. The reasons may be as follows:

[0024] The inner boundary of the first adhesive layer forms the boundary between the deformation zone and the bonding zone of the elastic film. The deformation zone produces deformation away from the first adhesive layer under the action of the pressure difference. The anti-detachment ring is connected to the outer ring of the elastic film (including the bonding zone or the outer ring of the bonding zone and the deformation zone) through the second adhesive layer. Since the hardness of the anti-detachment ring is higher than that of the elastic film, the overall stiffness of the region where the anti-detachment ring, the second adhesive layer and the outer ring of the elastic film are bonded together is greatly improved, forming a hard material similar to an integral body, forming an anti-separation whole with a larger area and a relatively uniformly dispersed deformation trend, inhibiting the local separation of the inner boundary of the bonding zone and the inner boundary of the first adhesive layer, so that bonding cannot be formed. The starting point of the local separation between the bonding area and the first adhesive layer is the separation point, so the separation cannot spread further outward. At this time, in order to separate the bonding area from the first adhesive layer, the rigid whole formed by the entire bonding area, the second adhesive layer and the anti-detachment ring must be completely separated from the first adhesive layer at one time along a direction approximately parallel to the axial direction, and the separation is extremely difficult. That is, the addition of the anti-detachment ring changes the separation mode of the bonding area and the first adhesive layer. Under the new separation mode, the rigid whole formed by the bonding area, the second adhesive layer and the anti-detachment ring must be completely separated from the first adhesive layer at one time along the axial direction, and the separation is extremely difficult, thereby solving the problem of separation of the bonding area from the first adhesive layer.

[0025] If the inner diameter of the anti-detachment ring is larger than the diameter of the deformation zone (that is, the inner diameter of the first adhesive layer), that is, the inner boundary of the anti-detachment ring is located radially outside the inner boundary of the first adhesive layer (that is, the inner boundary of the bonding zone), but the distance between the inner boundary of the anti-detachment ring and the inner boundary of the bonding zone is not greater than 30% of the inner diameter of the first adhesive layer, that is, the distance that the inner boundary of the anti-detachment ring moves outward relative to the inner boundary of the first adhesive layer will not be too large. The rigid body formed by the anti-detachment ring, the second adhesive layer and the bonding zone bonded together can still suppress deformation near the inner boundary of the bonding zone, and the deformation of the deformation zone under the action of the pressure difference is still relatively uniform, which can ensure the blasting stability and effective anti-detachment.

[0026] If the inner diameter of the anti-detachment ring is smaller than the diameter of the deformation zone (that is, the inner diameter of the first adhesive layer), that is, the inner boundary of the anti-detachment ring is located radially inside the inner boundary of the first adhesive layer (that is, the inner boundary of the bonding zone), similarly, the distance between the inner boundary of the anti-detachment ring and the outer boundary of the deformation zone is not greater than 30% of the inner diameter of the first adhesive layer, that is, the width of the radial overlap area between the inner ring of the anti-detachment ring and the outer ring of the deformation zone will not be too large, which has a relatively small impact on the deformation of the deformation zone, and the affected area of ​​the outer ring of the deformation zone will not be too large, thereby ensuring the stability of the bursting pressure difference, and the pressure relief performance after the bursting can also be guaranteed, that is, the deformation zone can stably burst and quickly relieve pressure under a high bursting pressure difference.

[0027] In the present application, an elastic membrane and a waterproof breathable membrane are combined to achieve the requirements of air permeability and balanced internal and external pressure difference under normal working conditions, and the elastic membrane is used to meet the design requirements of high explosion pressure difference and rapid pressure relief under high explosion pressure difference; and an anti-detachment ring is arranged on the surface of the elastic membrane away from the first adhesive layer, and the inner diameter D1 of the anti-detachment ring and the inner diameter D2 of the first adhesive layer satisfy |D1-D2| / D2 is not greater than 0.3, so that the anti-detachment ring, the second adhesive layer, and the outer ring of the elastic membrane (including the bonding area or the outer ring of the bonding area and the deformation area) are bonded together to form a rigid body, which, on the one hand, improves the deformation uniformity of the deformation zone and ensures the stability of the explosion pressure difference, and on the other hand, solves the problem of separation of the bonding area from the first adhesive layer.

[0028] It should be noted that the dimensions of the relevant components involved in this application, such as the inner diameter, width, and diameter, can be measured by cutting the explosion-proof membrane assembly along the extension direction of any diameter as needed, and then measuring it directly with a caliper or first magnifying the cut cross-section with a magnifying glass, microscope, or other equipment and then measuring the dimensions of each component. The results obtained by other conventional measurement methods are also acceptable.

[0029] Of course, industrial CT can also be used to directly measure the inner diameter, width, and diameter of related components without destroying the membrane components.

[0030] Furthermore, the resistance coefficient of the resistance ring is not less than 100, and the resistance coefficient is the product of the thickness of the resistance ring and its Vickers hardness.

[0031] If the thickness of the anti-detachment ring is small and the hardness is low, that is, the anti-detachment ring is thin and soft, and the anti-detachment coefficient is lower than 100, the strength and rigidity of the anti-detachment ring itself are also slightly low, and the rigidity of the whole formed by the anti-detachment ring, the second adhesive layer and the outer ring of the elastic membrane is also relatively poor. Then the inner boundary of the bonding area tends to be locally separated from the first adhesive layer. The probability of local separation between the inner boundary of the bonding area and the first adhesive layer is relatively large, that is, the inner boundary of the bonding area may be slightly locally separated from the first adhesive layer. Although the provision of the anti-detachment ring can avoid further expansion of this peeling, this uneven and unstable peeling phenomenon is obviously not conducive to the bursting stability of the membrane assembly. Therefore, when the anti-detachment coefficient is lower than 100, the stability of the bursting pressure difference is also reduced. It is preferred that the anti-detachment coefficient is greater than 100. On the one hand, it can avoid this phenomenon of unstable blasting as much as possible, and on the other hand, it can ensure a better solution to the peeling problem.

[0032] The unit of the thickness of the anti-slip ring is μm, and the unit of the Vickers hardness is HV 0.1 (HV represents Vickers hardness, and 0.1 represents that the load selected during the test is 0.1 kg).

[0033] The Vickers hardness of the anti-detachment ring can be measured by a microhardness tester named Innovationst Falcon 507. The test method is to select the appropriate load and holding time (generally 10-15s) according to the characteristics of the material being tested. After the test, the size of the indentation is measured by the software and the Vickers hardness value is displayed. Of course, in addition to the aforementioned models of equipment, the results measured by other models of Vickers hardness testing equipment that meet the relevant standards are also acceptable. It should be noted that when measuring the Vickers hardness of the anti-detachment ring, the explosion-proof membrane assembly is placed on the test equipment as a whole for measurement without removing the anti-detachment ring from the membrane assembly.

[0034] Preferably, the material that can be used as the anti-release ring can be common and easily processed polymer materials such as polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS), polycarbonate (PC) and polymethyl methacrylate (PMMA).

[0035] Furthermore, the resistance coefficient of the resistance ring is 4×10 2 ~1.5×10 5 .

[0036] It is preferred to control the resistance coefficient to be no less than 400, so that the explosion stability of the membrane assembly and the effect of preventing the bonding area from being separated from the first adhesive layer are more stable.

[0037] If the thickness of the anti-detachment ring is too large and the hardness is too high, its inner wall may hinder the bulging of the deformation zone, hinder the normal bulging of the deformation zone, and be unfavorable for the stable and rapid blasting of the deformation zone under high blasting pressure difference. The air permeability after blasting will decrease slightly. In particular, when the inner ring of the anti-detachment ring has a radially overlapping portion with the outer ring of the deformation zone, that is, D1 / D2 is between 0.7-1, and its hardness is relatively high, in addition to affecting the blasting stability of the deformation zone, there is also a risk of stabbing the outer ring of the deformation zone. If D1 / D2 is between 1-1.3, the bonding area of ​​the elastic membrane may be worn by the inner boundary of the anti-detachment ring.

[0038] For example, when the anti-detachment ring is made of a material such as metal or ceramic with high hardness, its anti-detachment effect is stable and reliable. However, during the entire service life of the membrane assembly, the deformation zone of the elastic membrane needs to swell and restore its original shape frequently, that is, the outer ring of the deformation zone will frequently contact the inner boundary of the anti-detachment ring and be frequently rubbed, which poses the risk of premature wear and rupture. Therefore, materials with high anti-detachment coefficients are not preferred.

[0039] Therefore, it is better that the resistance coefficient of the resistance ring does not exceed 1.5×10 5 .

[0040] In general, the thickness and Vickers hardness of the anti-detachment ring are not independent parameters. The two are inseparable and should be considered as a whole to prevent the bonding area from being separated from the first adhesive layer. A relatively high thickness should be used with a lower hardness, but the thickness should be avoided to be too large. A higher hardness can be appropriately reduced in thickness, but the hardness should also be avoided to be too high, and the product of the two, that is, the anti-detachment coefficient, should be maintained at 4×10 2 ~1.5×10 5 It can ensure that the anti-detachment ring is effective, ensure that the deformation zone of the elastic membrane can be stably exploded, and the outer circle of the deformation zone will not be punctured or punctured by the inner boundary of the anti-detachment ring.

[0041] Furthermore, the resistance coefficient is 9×10 2 ~1×10 4 , and the ratio D1 / D2 of the inner diameter D1 of the anti-detachment ring to the inner diameter D2 of the first adhesive layer is not less than 0.9 and not greater than 1.2.

[0042] In the membrane assembly of the present application, the hardness of the anti-detachment ring is higher than that of the elastic membrane, which can improve the explosion stability of the membrane assembly on the one hand, and avoid the problem of large deformation of the elastic membrane causing the bonding area to separate from the first adhesive layer on the other hand.

[0043] In order to avoid the anti-detachment ring from causing a large inhibition on the deformation of the elastic membrane, thereby affecting the bursting stability and pressure relief effect of the membrane assembly, the present application controls the ratio of D1 / D2 to be not less than 0.7. It is preferred to control the ratio of D1 / D2 to be not less than 0.9, which can reduce the influence of the anti-detachment ring on the bursting stability and pressure relief effect of the membrane assembly, so that the membrane assembly not only has a more stable bursting pressure difference, but also has a higher pressure relief capacity after bursting; and at the same time, the control of the anti-detachment coefficient is not less than 900, which means that although the effective impact area of ​​the anti-detachment ring has decreased, the anti-detachment capacity per unit area of ​​the anti-detachment ring has increased. The two are adjusted synchronously to ensure that the anti-detachment ring can still stably inhibit the local peeling of the inner boundary of the bonding area. Therefore, it is preferred to adjust the ratio of D1 / D2 and the anti-detachment coefficient that is adjusted synchronously, so that the membrane assembly has a more stable bursting pressure difference and a higher pressure relief capacity after bursting, and it can still ensure that the anti-detachment ring provides a stable and good anti-detachment effect.

[0044] It is preferred to control the resistance coefficient to be no less than 900, and at the same time control the ratio of D1 / D2 to be no more than 1.2, that is, optimize the maximum distance between the inner boundary of the resistance ring and the inner boundary of the first adhesive layer, so that the resistance ring can stably suppress the deformation of the inner ring of the bonding area, that is, the resistance coefficient and D1 / D2 are adjusted synchronously, and the bonding area forms a more complete whole to resist separation from the first adhesive layer, thereby ensuring a reliable resistance effect and avoiding the problem of decreased blasting stability due to a small amount of peeling of the inner ring of the bonding area.

[0045] The resistance coefficient is not more than 10000, and the wear on the outer ring of the deformation zone or the inner ring of the bonding zone can also be reduced.

[0046] Furthermore, the resistance coefficient is 9×10 2 ~1×10 4 , and a ratio D3 / D2 of an inner diameter D3 of the second adhesive layer to an inner diameter D2 of the first adhesive layer is not less than 0.9 and not greater than 1.2.

[0047] The ratio D3 / D2 of the inner diameter D3 of the second adhesive layer to the inner diameter D2 of the first adhesive layer reflects the relative positional relationship between the inner boundary of the second adhesive layer and the inner boundary of the bonding area. When the inner diameter of the second adhesive layer is smaller than the inner diameter of the first adhesive layer, the second adhesive layer has an annular portion extending into the inner boundary of the first adhesive layer, that is, it radially covers the inner boundary of the first adhesive layer and the inner boundary of the bonding area. The inner ring of the second adhesive layer is bonded to the outer ring of the deformation zone of the elastic membrane, which is equivalent to increasing the thickness of the outer ring of the deformation zone, and can inhibit the deformation of the outer ring of the deformation zone under the action of pressure difference to a certain extent. The bulging of the outer ring of the deformation zone under the action of pressure difference is limited, which can increase the difficulty of separation between the inner boundary of the bonding area and the first adhesive layer. When the inner diameter of the second adhesive layer is larger than the inner diameter of the first adhesive layer, the inner boundary of the second adhesive layer is located radially outside the inner boundary of the bonding area, which can reduce the adverse effects on the bulging and deformation of the deformation zone, and reduce the adverse effects on the stability of the bursting pressure difference of the membrane assembly and the pressure relief capacity after the bursting.

[0048] In the membrane assembly of the present application, the ratio D3 / D2 of the inner diameter D3 of the second adhesive layer to the inner diameter D2 of the first adhesive layer is controlled to be not less than 0.9, so as to reduce the negative impact of the second adhesive layer on the bursting stability and pressure relief effect of the membrane assembly as much as possible, so that the membrane assembly not only has a more stable bursting pressure difference, but also has a higher post-burst pressure relief capacity; at the same time, it is preferred to control the resistance coefficient to be not less than 900, so as to improve the resistance capacity of the resistance ring. Therefore, the ratio D3 / D2 of the inner diameter D3 of the second adhesive layer to the inner diameter D2 of the first adhesive layer is optimized at the same time, and the resistance coefficient is adjusted synchronously, so that the membrane assembly can have a more stable bursting pressure difference and a higher post-burst pressure relief capacity, while still ensuring that the resistance ring provides a stable and good resistance effect.

[0049] It is preferred to control the resistance coefficient to be no less than 900, and at the same time control the ratio of D3 / D2 to be no more than 1.2, that is, to optimize the maximum distance between the inner boundary of the second adhesive layer and the inner boundary of the first adhesive layer. On the one hand, the influence of the second adhesive layer on the bursting and pressure relief performance of the deformation zone can be minimized as much as possible. On the other hand, the area where the second adhesive layer is bonded to the resistance ring and the bonding area is wide enough and the rigidity is high enough to stably suppress the separation of the inner boundary of the bonding area from the first adhesive layer, thereby providing a relatively stable resistance effect, thereby providing a more stable bursting pressure difference and a higher air permeability after bursting under the premise of stable resistance effect.

[0050] Furthermore, a ratio W2 / W1 of a width W2 of the second adhesive layer to a width W1 of the first adhesive layer is not less than 0.5.

[0051] In the present application, the inner diameter D1 of the anti-detachment ring and the inner diameter D2 of the first adhesive layer are controlled to satisfy |D1-D2| / D2 is not greater than 0.3, which ensures the basic anti-detachment effect and bursting performance requirements. It is further preferred to control the ratio of the width W2 of the second adhesive layer to the width W1 of the first adhesive layer W2 / W1 to be not less than 0.5, which ensures that the bonding strength between the second adhesive layer and the outer ring of the anti-detachment ring and the elastic membrane is sufficiently high, and the overall stiffness of the area where the anti-detachment ring, the second adhesive layer, and the outer ring of the elastic membrane are bonded into one is also high enough, which further improves the stability of the bursting pressure difference and has a sufficiently good pressure relief performance after the burst. For example, if W2 / W1 is less than 0.5, such as a value of 0.4, the stability of the bursting pressure difference of the membrane assembly will decrease.

[0052] Furthermore, a ratio W2 / W3 of a width W2 of the second adhesive layer to a width W3 of the anti-detachment ring is not less than 0.5.

[0053] In the present application, the inner diameter D1 of the anti-detachment ring and the inner diameter D2 of the first adhesive layer are controlled to satisfy |D1-D2| / D2 not greater than 0.3, which ensures the basic anti-detachment effect and bursting performance requirements. It is further preferred to control the ratio W2 / W3 of the width W2 of the second adhesive layer to the width W3 of the anti-detachment ring to be not less than 0.5, that is, the area where the anti-detachment ring is bonded by the second adhesive layer is wide enough, and the anti-detachment ring is bonded firmly enough, which is conducive to maintaining the position stability of the anti-detachment ring, and also plays a role in improving the overall rigidity formed by the bonding of the anti-detachment ring, the second adhesive layer and the outer ring of the elastic membrane, thereby improving the stability of the bursting pressure difference and having a sufficiently good pressure relief performance after the bursting. W2 / W3 is less than 0.5. If the value is 0.3, the stability of the bursting pressure difference of the membrane assembly will decrease.

[0054] Furthermore, a ratio W1 / D0 of a width W1 of the first adhesive layer to a diameter D0 of the elastic film is not less than 0.1 and not more than 0.4.

[0055] In the present application, the inner diameter D1 of the anti-detachment ring and the inner diameter D2 of the first adhesive layer are controlled to satisfy |D1-D2| / D2 not greater than 0.3, thereby ensuring the basic anti-detachment effect and blasting performance requirements. It is further preferred to control the ratio W1 / D0 of the width W1 of the first adhesive layer to the diameter D0 of the elastic film to be not less than 0.1, thereby ensuring the bonding strength between the bonding area of ​​the elastic film and the first adhesive layer, increasing the difficulty of separation between the two, and ensuring the stability of the blasting pressure difference. At the same time, the ratio W1 / D0 of the width W1 of the first adhesive layer to the diameter D0 of the elastic film is controlled to be not greater than 0.4, thereby better meeting the requirements for product miniaturization and avoiding the deterioration of the blasting performance due to the excessive width of the bonding area.

[0056] Furthermore, a ratio H1 / D2 of a burst height H1 of the elastic film to an inner diameter D2 of the first adhesive layer is 1-45.

[0057] In the present application, the inner diameter D1 of the anti-detachment ring and the inner diameter D2 of the first adhesive layer are controlled to satisfy |D1-D2| / D2 is not greater than 0.3, thereby ensuring the basic anti-detachment effect and blasting performance requirements. The inner diameter of the first adhesive layer is also the original diameter of the deformation zone of the elastic membrane before deformation.

[0058] When the pressure difference reaches the bursting pressure difference, the height of the deformation zone of the elastic membrane is high enough, the deformation is large enough, and the ratio of the bursting height H1 to the inner diameter D2 of the first adhesive layer is between 1-45, that is, when the bursting pressure difference is reached, the deformation zone of the elastic membrane is stretched sufficiently large and thin enough, so that the rupture generated during the bursting is larger and the pressure can be released quickly. This ratio does not exceed 45, which can further ensure that the membrane assembly has stable anti-peeling performance and avoid the problem of decreased bursting pressure stability due to a small amount of local irregular peeling.

[0059] Furthermore, the waterproof and breathable membrane is an annular PTFE microporous membrane, the inner edge of which is bonded to the surface of the first adhesive layer away from the elastic membrane.

[0060] As a waterproof and breathable membrane, PTFE microporous membrane has the advantages of waterproof, stable breathability, corrosion resistance, etc. Moreover, the surface of PTFE microporous membrane is relatively smooth, easy to form a tight bond with the first adhesive layer, and has a good sealing effect. In addition, the annular PTFE microporous membrane is bonded to the outer ring of the elastic membrane to form an integrated explosion-proof membrane assembly, which has a more compact structure, occupies a small area, and is also convenient for further installation and fixation.

[0061] Furthermore, a third adhesive layer is bonded to the surface of the waterproof breathable membrane away from the first adhesive layer, and a support net for limiting the concave deformation of the elastic membrane is bonded to the surface of the third adhesive layer away from the waterproof breathable membrane, and the thickness of the support net is 70-150 μm.

[0062] Under the impact of water flow, the deformation area of ​​the elastic membrane will be concave in the direction of the support net, and the support net will limit it, control the amplitude of the concave deformation of the elastic membrane, and protect the deformation area. The thickness of the support net cannot be too small, otherwise its own strength will be low and the support strength for the deformation area will be insufficient. Of course, the thickness of the support net should not be too large, otherwise, it is easy to be loosely bonded. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 Schematic diagram of the structure of the explosion-proof membrane assembly provided in the embodiment of the present invention Figure 1 ;

[0064] Figure 2Schematic diagram of the structure of the explosion-proof membrane assembly provided in the embodiment of the present invention Figure 2 ;

[0065] Figure 3 Schematic diagram of the structure of the explosion-proof membrane assembly provided in the embodiment of the present invention Figure 3 .

[0066] Among them, 10-explosion-proof membrane assembly, 11-elastic membrane, 111-deformation zone, 112-adhesive zone, 12-waterproof and breathable membrane, 13-first adhesive layer, 14-second adhesive layer, 15-anti-detachment ring, 16-third adhesive layer, 17-support mesh, and 18-fourth adhesive layer. DETAILED DESCRIPTION

[0067] The explosion-proof membrane assembly provided in this application is introduced in detail below.

[0068] like Figure 1 The explosion-proof membrane assembly 10 shown includes an elastic membrane 11 and a waterproof breathable membrane 12. The waterproof breathable membrane 12 can be a PTFE microporous membrane. A first adhesive layer 13 is fixed to the outer edge of the axial side surface of the elastic membrane 11. The elastic membrane 11 includes a deformation zone 111 located radially inside the first adhesive layer 13 and a bonding zone 112 corresponding to the first adhesive layer 13; an outer edge of the surface of the elastic membrane 11 facing away from the first adhesive layer 13 is bonded with a detachment-blocking ring 15 through an annular second adhesive layer 14, and the hardness of the detachment-blocking ring 15 is higher than that of the elastic membrane 11.

[0069] The explosion-proof membrane assembly 10 can be directly installed at the opening of the shell (not shown in the figure) of the device (such as a battery pack). Specifically: the waterproof and breathable membrane 12 is an annular PTFE microporous membrane, and its inner edge is bonded to the surface of the first adhesive layer 13 away from the elastic membrane 11, so that the elastic membrane 11 and the waterproof and breathable membrane 12 form a whole, and the whole is then bonded to the opening of the shell through the third adhesive layer 16 located on the side of the waterproof and breathable membrane 12 away from the first adhesive layer 13. Correspondingly, the second adhesive layer 14 and the anti-detachment ring 15 are away from the shell. It should be noted that the explosion-proof membrane assembly 10 can also be bonded to a valve body similar to the prior art, and the valve body is then installed at the opening of the shell of the battery pack through threads or other connecting structures.

[0070] Or, if Figure 2As shown, the surface of the waterproof breathable membrane 12 away from the first adhesive layer 13 is bonded with a third adhesive layer 16, and the surface of the third adhesive layer 16 away from the waterproof breathable membrane 12 is bonded with a support net 17 for limiting the concave deformation of the elastic membrane 11, and the thickness of the support net 17 is 70-150μm. Under the impact of water flow, the deformation area 111 of the elastic membrane 11 will be concave in the direction of the support net 17, and the support net 17 will have a limiting effect on it, control the amplitude of the concave deformation of the elastic membrane 11, and protect the deformation area 111. The thickness of the support net 17 cannot be too small, otherwise its own strength is low and the support strength of the deformation area 111 is insufficient. Of course, the thickness of the support net 17 is not easy to be too large, otherwise it is easy to be loosely bonded. The support net 17 is then bonded to the opening of the shell through the fourth adhesive layer 18 fixed on its surface away from the third adhesive layer 16.

[0071] The film-forming material of the elastic film 11 is selected from one of PDMS, latex, PU, ​​EVA, POE, TPO, TPE or TPV. PDMS refers to polydimethylsiloxane, PU refers to polyurethane, EVA refers to ethylene vinyl acetate copolymer, POE refers to polyethylene octene copolymer, TPO refers to polyolefin thermoplastic elastomer, TPE refers to thermoplastic elastomer material, and TPV refers to thermoplastic vulcanized rubber.

[0072] It is understandable that the elastic membrane 11 and the waterproof breathable membrane 12 constituting the explosion-proof membrane assembly 10 can also be provided in a split type, such as Figure 3 As shown, the elastic membrane 11 and the anti-detachment ring 15 are bonded into one body through the second adhesive layer 14 and bonded to one opening of the shell through the first adhesive layer 13, while the circular waterproof breathable membrane 12 is bonded to another opening of the shell through the third adhesive layer 16.

[0073] Example 1

[0074] The explosion-proof membrane assembly 10 includes an elastic membrane 11 and a waterproof breathable membrane 12. A first adhesive layer 13 is fixed to the outer edge of the axial side surface of the elastic membrane 11. The elastic membrane 11 includes a deformation zone 111 located radially inside the first adhesive layer 13 and a bonding zone 112 corresponding to the first adhesive layer 13. The outer edge of the surface of the elastic membrane 11 on the side away from the first adhesive layer 13 is bonded with a detachment-blocking ring 15 through an annular second adhesive layer 14. The inner edge of the waterproof breathable membrane 12 is bonded to the surface of the first adhesive layer 13 away from the elastic membrane 11, and the outer edge of the waterproof breathable membrane 12 on the side away from the first adhesive layer 13 is bonded with an annular third adhesive layer 16. That is, the laminated structure of the explosion-proof membrane assembly 10 is as follows: Figure 1 shown.

[0075] The elastic film 11 is made of PDMS, with a thickness T0 of 10.2 μm, the anti-detachment ring 15 is made of PET, with an inner diameter D1 of 5 mm, the inner diameter D2 of the first adhesive layer 13 is 5 mm, and accordingly, D1 / D2 is 1, and the anti-detachment coefficient of the anti-detachment ring 15 is 1300. The inner diameter D3 of the second adhesive layer 14 is 5 mm, and accordingly, D3 / D2 is 1, the width W1 of the first adhesive layer is 3.5 mm, the width W2 of the second adhesive layer is 3.5 mm, and accordingly, W2 / W1 is 1, the width W3 of the anti-detachment ring 15 is 3.5 mm, and accordingly, W2 / W3 is 1, the diameter D0 of the elastic film is 12 mm, and accordingly, W1 / D0 is 0.29. Accordingly, the effective diameter of the deformation zone 111 of the elastic film 11 is also 5 mm.

[0076] The measured bursting pressure difference is 16.3kPa, and the air permeability after bursting is 108.2L / min@4kpa. The test method is as follows.

[0077] Testing method for the bursting pressure difference of the explosion-proof membrane assembly 10: preset the gas source pressure, then seal and bond the explosion-proof membrane assembly 10 to the opening of the fixture connected to the gas source, and observe whether the elastic membrane 11 bursts; if no explosion occurs under a certain preset gas source pressure, disconnect the explosion-proof membrane assembly 10 from the gas source, and increase the preset pressure of the gas source with a gradient of 0.1 kpa, repeat the above operation until the explosion-proof membrane assembly 10 bursts under a certain preset gas source pressure, and record the preset gas source pressure at this time, which is the bursting pressure difference of the explosion-proof membrane assembly 10.

[0078] The testing process of the air permeability data of the explosion-proof membrane assembly 10 after the explosion of the elastic membrane 11 is as follows: the explosion-proof membrane assembly 10 after the explosion of the elastic membrane 11 is used as a test sample, and the gas source pressure is preset to 4kpa, and then the explosion-proof membrane assembly 10 is connected to the gas source, and the amount of gas passing through the explosion-proof membrane assembly 10 within a certain period of time is measured, and the air permeability of the explosion-proof membrane assembly 11 after the explosion of the elastic membrane 11 is calculated accordingly.

[0079] Embodiment 2-5

[0080] The main difference between Example 2-5 and Example 1 is that the thickness T0 of the elastic film 11 is adjusted while the inner diameter D1 of the anti-detachment ring 15, the inner diameter D2 of the first adhesive layer 13, the inner diameter D3 of the second adhesive layer 14, the width W1 of the first adhesive layer, the width W2 of the second adhesive layer, the width W3 of the anti-detachment ring 15, and the diameter D0 of the elastic film 11 are kept unchanged. See Table 1 and Table 2 for details.

[0081] Example 6

[0082] The difference compared with Example 3 is that, on the basis of maintaining other parameters unchanged, the inner diameter D1 of the anti-slip ring 15 is reduced to 3.5 mm, and accordingly, D1 / D2 is 0.7, as shown in Table 1 and Table 2 for details.

[0083] Example 7

[0084] The difference compared with Example 3 is that, on the basis of keeping other parameters unchanged, the inner diameter D1 of the anti-slip ring 15 is increased to 6.5 mm, and accordingly, D1 / D2 is 1.3, as shown in Tables 1 and 2 for details.

[0085] Example 8

[0086] Compared with Example 1, the thickness of the anti-detachment ring 15 is thinner and the Vickers hardness is lower. The material of the anti-detachment ring 15 is PE, and its anti-detachment coefficient is lower than 100. The material of the elastic film 11 is PDMS. See Table 1 and Table 2 for details.

[0087] Example 9

[0088] Compared with Example 5, the material of the anti-detachment ring 15 is aluminum nitride ceramic, which has a higher Vickers hardness and a resistance coefficient of more than 1.5×10 5 The test found that after the elastic membrane 11 made of PDMS performed multiple swelling and recovery, the outer ring of the deformation zone 111 was worn by the inner boundary of the blocking ring 15.

[0089] Example 10

[0090] Compared with Example 6, on the basis of keeping other parameters unchanged, the inner diameter D1 of the anti-slip ring 15 is increased to 4.5 mm, and accordingly, D1 / D2 is 0.9, as shown in Tables 1 and 2 for details.

[0091] Embodiment 11

[0092] Compared with Example 10, on the basis of maintaining other parameters unchanged, the resistance coefficient of the resistance ring 15 is reduced to 840, as shown in Table 1 and Table 2 for details.

[0093] Example 12

[0094] Compared with Example 3, on the basis of keeping other parameters unchanged, the inner diameter D3 of the second adhesive layer 14 is reduced to 4.5 mm, and accordingly, the value of D3 / D2 is 0.9, as shown in Tables 1 and 2 for details.

[0095] Example 13

[0096] Compared with Example 12, on the basis of maintaining other parameters unchanged, the resistance coefficient of the resistance ring 15 is reduced to 840, as shown in Tables 1 and 2 for details.

[0097] Comparative Example

[0098] Comparative Example 1

[0099] Compared with Example 1, on the basis of keeping other parameters unchanged, the thickness of the elastic membrane 11 is thinner, only 7.8 μm, and the bursting pressure difference of the membrane assembly is 12.7 kPa, which is lower than 16 kPa and does not meet the design value requirement of the bursting pressure difference. For details, see Table 1 and Table 2.

[0100] Comparative Example 2

[0101] Compared with Example 5, on the basis of keeping other parameters unchanged, the thickness of the elastic membrane 11 is 546 μm, and the bursting pressure difference of the membrane assembly is 122.9 kPa, which exceeds 100 kPa and does not meet the design value requirement of the bursting pressure difference. See Table 1 and Table 2 for details.

[0102] Comparative Example 3

[0103] Compared with Example 3, on the basis of maintaining other parameters unchanged, the inner diameter D1 of the anti-detachment ring 15 is reduced to 3 mm, and accordingly, D1 / D2 is 0.6, and the air permeability after blasting is 22.6 L / min@4 kpa, as shown in Tables 1 and 2 for details.

[0104] Comparative Example 4

[0105] The difference compared with Example 3 is that, on the basis of maintaining the other parameters unchanged, the inner diameter D1 of the anti-detachment ring 15 is increased to 7 mm, and accordingly, D1 / D2 is 1.4. The test found that before the explosion-proof membrane assembly 10 explodes, the bonding area 112 of the elastic membrane 11 is completely detached from the first adhesive layer 13.

[0106] Comparative Example 5

[0107] In the explosion-proof valve provided by prior art CN218648096U, when the diameter of the effective deformation zone of the PTFE microporous membrane is 25mm and the axial spacing between the microporous membrane and the puncture piece is 0.8-1.2mm, the burst pressure difference is 5-15kPa. In comparative example 5, the diameter of the effective deformation zone of the PTFE microporous membrane is set to 20mm, and the axial spacing between the microporous membrane and the puncture piece is increased to 2mm. At this time, the burst pressure difference of the explosion-proof valve is 42.6kPa (close to the burst pressure difference of Example 3 of the present application), which meets the requirement that the burst pressure difference design value is between 16-100kPa. However, the breach formed after the explosion is very small, and the air permeability after the explosion does not exceed 10L / min@4kpa, which is much lower than the air permeability of the elastic membrane 11 corresponding to Example 3 after the explosion, and the requirement of rapid pressure relief cannot be achieved.

[0108] Tables 1 and 2 below list the design parameter selections and corresponding performance parameters of each embodiment and comparative example.

[0109] Table 1 Design parameter selection of each embodiment and comparative example

[0110]

[0111]

[0112] Wherein, W1 refers to the width of the first adhesive layer 13, W2 refers to the width of the second adhesive layer 14, W3 refers to the width of the anti-detachment ring 15, and D0 refers to the diameter of the elastic membrane 11; in all the above embodiments and comparative examples, W1, W2, and W3 are all 3.5 mm, and D0 is 12 mm.

[0113] Table 2 Performance parameters of various embodiments and comparative examples

[0114]

[0115] in conclusion

[0116] According to the technical solutions and test data of Examples 1-5 and Comparative Examples 1-5, it can be known that in the present application, the elastic membrane 11 and the waterproof breathable membrane 12 are combined to achieve the requirements of air permeability and balance of internal and external pressure difference under normal working conditions, and the elastic membrane 11 is used to meet the design requirements of high explosion pressure difference and rapid pressure relief under high explosion pressure difference. The measurement results of the explosion pressure difference are all between 16-100kPa, and the air permeability after the explosion is also above 60L / min@4kpa; and by the elastic membrane 11 away from the first adhesive layer 13 A detachment-preventing ring 15 is provided on the surface of one side, and when the inner diameter D1 of the detachment-preventing ring 15 and the inner diameter D2 of the first adhesive layer 13 satisfy |D1-D2| / D2 is not greater than 0.3, the detachment-preventing ring 15, the second adhesive layer 14, and the outer ring of the elastic membrane 11 (including the bonding area 112 or the outer ring of the bonding area 112 and the deformation area 111) are bonded together to form a rigid body. On the one hand, the deformation uniformity of the deformation area 111 is improved to ensure the stability of the bursting pressure difference. On the other hand, the problem of the bonding area 112 and the first adhesive layer 13 being detached is solved.

[0117] Compared with Example 3, the air permeability of the explosion-proof membrane assembly 10 after explosion in Example 6 is significantly reduced; compared with Example 3, there is a certain deviation in the multiple measured values ​​of the explosion pressure difference of the explosion-proof membrane assembly 10 in Example 7, that is, the stability of the explosion pressure difference is poor.

[0118] Compared with Example 1, the test of Example 8 found that the multiple measured values ​​of the bursting pressure difference of the explosion-proof membrane assembly 10 had a certain deviation, that is, the stability of the bursting pressure difference was poor. Compared with Example 5, the test of Example 9 found that after the elastic membrane 11 performed multiple swelling and recovery, the outer ring of the deformation zone 111 was worn by the inner boundary of the blocking ring 15.

[0119] Compared with Example 6, the test of Example 10 found that the air permeability of the explosion-proof membrane assembly 10 after the explosion is higher than that of the corresponding explosion-proof membrane assembly 10 after the explosion of Example 6, and the measured value of the explosion pressure difference is relatively stable. Compared with Example 10, the test of Example 11 found that the air permeability of the explosion-proof membrane assembly 10 after the explosion is basically the same as that of the corresponding explosion-proof membrane assembly 10 after the explosion of Example 10, but there is a certain deviation in the measured value of the explosion pressure difference.

[0120] Compared with Example 3, the test found that the stability of the bursting pressure difference of the explosion-proof membrane assembly 10 of Example 12 is better than that of the corresponding explosion-proof membrane assembly 10 of Example 3, and the air permeability of the former after the explosion is only slightly reduced. Compared with Example 12, the test found that the air permeability of the explosion-proof membrane assembly 10 after the explosion of Example 13 is basically the same as that of the corresponding explosion-proof membrane assembly 10 after the explosion of Example 12, but there is a certain deviation in the measured value of the bursting pressure difference.

[0121] According to the technical solutions of Examples 1-7, 9-13 and various test data, it is not difficult to find that when the pressure difference reaches the bursting pressure difference, the height of the deformation zone of the elastic membrane bulges high enough, the deformation generated is large enough, and the ratio of the bursting height H1 to the inner diameter D2 of the first adhesive layer falls between 1-45, that is, when the bursting pressure difference is reached, the deformation zone of the elastic membrane is stretched sufficiently large, and the deformation zone is stretched thin enough, so that the rupture generated during the explosion is larger, and the pressure can be released quickly. At the same time, the tendency of the bonding area 112 to separate from the first adhesive layer 13 is avoided to be too large, thereby ensuring that the anti-detachment ring 15 can provide a relatively stable anti-detachment effect.

[0122] Better, in the present application, on the basis of controlling the inner diameter D1 of the anti-detachment ring and the inner diameter D2 of the first adhesive layer to satisfy |D1-D2| / D2 not greater than 0.3, the basic anti-detachment effect and bursting performance requirements are guaranteed, and it is further preferred to control the ratio of the width W2 of the second adhesive layer to the width W1 of the first adhesive layer W2 / W1 not less than 0.5, to ensure that the bonding strength between the second adhesive layer and the outer ring of the anti-detachment ring and the elastic membrane is higher, the overall stiffness of the area where the anti-detachment ring, the second adhesive layer, and the outer ring of the elastic membrane are bonded together is also higher, the stability of the bursting pressure difference is better, and the pressure relief performance after the bursting is also better. For example, if W2 / W1 is less than 0.5, such as a value of 0.4, the stability of the bursting pressure difference of the membrane assembly will decrease.

[0123] More preferably, in the present application, on the basis of controlling the inner diameter D1 of the anti-detachment ring and the inner diameter D2 of the first adhesive layer to satisfy |D1-D2| / D2 not greater than 0.3, the basic anti-detachment effect and bursting performance requirements are guaranteed, and it is further preferred to control the ratio of the width W2 of the second adhesive layer to the width W3 of the anti-detachment ring W2 / W3 not less than 0.5, that is, the area where the anti-detachment ring is bonded by the second adhesive layer is wide enough, and the anti-detachment ring is bonded firmly enough, which is conducive to maintaining the position stability of the anti-detachment ring, and also plays a role in improving the overall rigidity formed by the bonding of the anti-detachment ring, the second adhesive layer and the outer ring of the elastic membrane, thereby improving the stability of the bursting pressure difference and having a sufficiently good pressure relief performance after the bursting. W2 / W3 is less than 0.5. If the value is 0.3, the stability of the bursting pressure difference of the membrane assembly will decrease.

[0124] Preferably, in the present application, the basic anti-detachment effect and blasting performance requirements are guaranteed on the basis of controlling the inner diameter D1 of the anti-detachment ring and the inner diameter D2 of the first adhesive layer to satisfy |D1-D2| / D2 is not greater than 0.3, and further preferably controlling the ratio W1 / D0 of the width W1 of the first adhesive layer to the diameter D0 of the elastic film to be not less than 0.1, to ensure the bonding strength between the bonding area of ​​the elastic film and the first adhesive layer, increase the difficulty of separation between the two, and ensure the stability of the blasting pressure difference, and at the same time, controlling the ratio W1 / D0 of the width W1 of the first adhesive layer to the diameter D0 of the elastic film to be not greater than 0.4, to better meet the requirements of product miniaturization, and to avoid the deterioration of blasting performance due to the excessive width of the bonding area. When W1 / D0 is less than 0.1, the problem of poor blasting stability of the explosion-proof membrane assembly may occur.

Claims

1. An explosion-proof membrane assembly, characterized in that: It comprises an elastic film and a waterproof breathable film, wherein the thickness T0 of the elastic film is 10-500 μm, a first adhesive layer is fixed to the outer edge of the surface of one axial side of the elastic film, and the elastic film comprises a deformation zone located radially inside the first adhesive layer and a bonding zone corresponding to the first adhesive layer; The outer edge of the elastic membrane surface facing away from the first adhesive layer is bonded with an anti-detachment ring through an annular second adhesive layer. The hardness of the anti-detachment ring is higher than that of the elastic membrane. The inner diameter D1 of the anti-detachment ring and the inner diameter D2 of the first adhesive layer satisfy |D1-D2| / D2 is not greater than 0.

3.

2. The explosion-proof membrane assembly according to claim 1, characterized in that: The resistance coefficient of the resistance ring is not less than 100, and the resistance coefficient is the product of the thickness of the resistance ring and its Vickers hardness.

3. The explosion-proof membrane assembly according to claim 2, characterized in that: The resistance coefficient of the resistance ring is 4×10 2 ~1.5×10 5 .

4. The explosion-proof membrane assembly according to claim 3, characterized in that: The resistance coefficient is 9×10 2 ~1×10 4 , and the ratio D1 / D2 of the inner diameter D1 of the anti-detachment ring to the inner diameter D2 of the first adhesive layer is not less than 0.9 and not greater than 1.

2.

5. The explosion-proof membrane assembly according to claim 3, characterized in that: The resistance coefficient is 9×10 2 ~1×10 4 , and a ratio D3 / D2 of an inner diameter D3 of the second adhesive layer to an inner diameter D2 of the first adhesive layer is not less than 0.9 and not greater than 1.

2.

6. The explosion-proof membrane assembly according to claim 1, characterized in that: A ratio W2 / W1 of a width W2 of the second adhesive layer to a width W1 of the first adhesive layer is not less than 0.

5.

7. The explosion-proof membrane assembly according to claim 1, characterized in that: A ratio W2 / W3 of a width W2 of the second adhesive layer to a width W3 of the anti-detachment ring is not less than 0.

5.

8. The explosion-proof membrane assembly according to claim 1, characterized in that: A ratio W1 / D0 of a width W1 of the first adhesive layer to a diameter D0 of the elastic film is not less than 0.

1.

9. The explosion-proof membrane assembly according to claim 1, characterized in that: The ratio H1 / D2 of the bursting height H1 of the elastic film to the inner diameter D2 of the first adhesive layer is 1-45.

10. The explosion-proof membrane assembly according to any one of claims 1 to 9, characterized in that: The waterproof and breathable membrane is a ring-shaped PTFE microporous membrane, the inner edge of which is bonded to the surface of the first adhesive layer away from the elastic membrane.

11. The explosion-proof membrane assembly according to claim 10, characterized in that: The surface of the waterproof breathable membrane away from the first adhesive layer is bonded with a third adhesive layer, and the surface of the third adhesive layer away from the waterproof breathable membrane is bonded with a support net for limiting the concave deformation of the elastic membrane, and the thickness is 70-150 μm.

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