CN217822881U - Fuel cell sealing structure - Google Patents

Abstract

The utility model provides a fuel cell sealing structure, which comprises a polar plate, a membrane electrode with a frame and a gas diffusion layer, and a sealing element arranged in a sealing groove; the sealing structure is divided into a gas port area sealing structure, a gap bridge area sealing structure and a reaction area sealing structure; the sealing element at least comprises a surface layer, a middle layer and a bottom layer; the middle layer is a sealing material with Shore hardness of 70-90, the surface layer and the bottom layer are bonding materials, the thickness ratio of the surface layer to the middle layer to the bottom layer is 1-8. The utility model discloses a different regional seal structure of subregion design, cooperation sealing member multilayer material adopts the great sealing material of hardness and the bonding material cooperation of superficial layer, bottom, has solved the problem that compressed seal became invalid easily in the past, has improved sealed reliability greatly, has reduced the design degree of difficulty.

Description

Fuel cell sealing structure

[ technical field ] A

The utility model relates to a fuel cell technical field especially relates to proton exchange membrane fuel cell seals the field.

[ background ] A method for producing a semiconductor device

The proton exchange membrane fuel cell is composed of membrane electrode and bipolar plate with gas flow channel which are alternatively stacked. The membrane electrode comprises a frame, a proton exchange membrane, a catalyst layer and a gas diffusion layer, and the metal bipolar plate is generally formed by welding an anode plate and a cathode plate. The bipolar plate has a fuel (e.g., hydrogen) on one side, an oxidant (e.g., air) on the other side, and a cooling medium (e.g., water, ethylene glycol) in the middle, as shown in fig. 1. In a fuel cell, fuel, an oxidant and a cooling medium need to flow in respective independent channels, and therefore, a sealing structure needs to be provided between a plate and a membrane electrode for sealing, so that cross connection and external leakage cannot be generated.

The design of the seal structure generally comprises two parts: 1. the inner seal distribution design of the bipolar plate plane; 2. the section of the sealing medium in the cell compression direction is designed. The main task of in-plane seal design is to accomplish the placement of the seal path; the sealing medium section design is related to the stability of sealing, and the stability problem runs through the product life cycle of the whole sealing part.

At present, the whole polar plate is generally designed by using one characteristic region in a sealing design, but the functions and mechanical properties of different positions of the polar plate are different, and the sealing reliability of the whole polar plate cannot be ensured by the design method. The air port area and the outer ring of the polar plate are sealed, the sealing elements are opposite one to one, the sealing elements are arranged in a staggered mode in the gap bridge area, the other side, opposite to the membrane electrode, of each sealing element corresponds to a boss of the polar plate, theoretically, a certain gap is formed between the boss and the frame, and compensation needs to be carried out by the sealing elements on the opposite side, so that the problems that the compression amount of the sealing elements is insufficient, and air leakage occurs are easily caused.

A common sealing element is sealed by compression, a series of problems such as positioning, limiting, compression rate, filling rate and the like of the sealing element need to be considered emphatically in the compression process, for example, CN112310433A, the sealing element is easy to extrude out of a sealing groove under pneumatic load impact to cause failure when compressed; the gap bridge area is limited by a gas flow structure, the sealing elements are arranged in a staggered manner, the opposite side of the sealing element on one side is a ridge structure of the polar plate on the other side, the sealing elements on the reaction area and the gas port area are symmetrically arranged relative to the membrane electrode, the whole polar plate is designed by using one characteristic area, the sealing compression amount of the gap bridge area is insufficient, and the sealing reliability is poor; although the sealing structure proposed in CN104538654B can limit the position of the sealing rubber line and the sealing groove from each other, the stress distribution of the rubber line located on the outer edge after compression is not uniform, the filling is not sufficient, and there is a risk of breaking in a local area, so that the part can only play an insulating role, and cannot realize sealing. The sealing function is mainly provided by a part of rubber lines in the sealing groove, but the part is narrow in width, sealing failure is easily caused when the assembly error is large, and the reliability is low; the sealing structure positioning unit provided by CN 215815951U mainly solves the problem of bonding, and still cannot solve the problem of avoiding air flow impact during installation limiting and compression. Therefore, the sealing structures can solve part of problems in compression, but the general requirements on the structure, the material and the installation of the sealing element are high, and improper structure, size and arrangement easily cause sealing failure, membrane electrode structure failure and even serious results.

[ Utility model ] content

The utility model discloses a different regional seal structure of subregion design, cooperation sealing member multilayer material adopts the great sealing material of hardness and the bonding material cooperation of superficial layer, bottom, has solved the problem that compressed seal became invalid easily in the past, has improved sealed reliability greatly, has reduced the design degree of difficulty.

The utility model discloses technical scheme is through following realization:

a fuel cell sealing structure is characterized by comprising a polar plate, a membrane electrode with a frame and a gas diffusion layer, and a sealing element arranged in a sealing groove; the sealing structure is divided into a gas port area sealing structure, a gap bridge area sealing structure and a reaction area sealing structure, and an anode side sealing element and a cathode side sealing element in the gas port area sealing structure and the reaction area sealing structure are symmetrically arranged on two sides of the membrane electrode; the anode layer sealing element and the cathode side sealing element in the bridge region sealing structure are arranged on two sides of the membrane electrode in a staggered manner; the height of the sealing element in the bridge region sealing structure is greater than the height of the sealing element in the reaction region sealing structure and the sealing element in the gas port region sealing structure; the sealing element at least comprises a surface layer, a middle layer and a bottom layer; the middle layer is a sealing material with Shore hardness of 70-90, the surface layer and the bottom layer are bonding materials, the thickness ratio of the surface layer to the middle layer to the bottom layer is 1.

Further, the anode side sealing piece in the gap bridge area sealing structure corresponds to the gap bridge supporting platform of the cathode plate, and the cathode side sealing piece corresponds to the gap bridge supporting platform of the anode plate; more preferably, the width of the bridge support platform is no less than the width of the anode side and cathode side seals.

Further, the bonding material of the surface layer and the bottom layer is selected from thermosetting type or normal temperature curing type materials, preferably silica gel, thermoplastic resin, and the like.

Further, the material of the middle layer is selected from EPDM, fluororubber and the like.

Further, the sealing member may be trapezoidal or rectangular.

Furthermore, the contact width of the surface layer and the polar plate is preferably 3.5mm, and the contact width of the bottom layer and the membrane electrode frame is preferably 2.5mm.

Furthermore, the polar plate is provided with a polar plate outer edge boss and a flow field connecting boss, and a sealing groove is formed between the polar plate outer edge boss and the flow field connecting boss; the bottom of the sealing groove is provided with a sealing groove internal rib structure with the median line length of 0.5-1mm; the sealing element is arranged in the polar plate sealing groove, the bottom of the sealing element stretches across the rib structure in the sealing groove, and the top of the sealing element is in plane contact with the frame of the membrane electrode; and the rib structure in the sealing groove is matched with the sealing element, and the frame and the polar plate of the membrane electrode are compressed to form space sealing.

Furthermore, the height of the rib structure in the sealing groove is not higher than the height of the flow field connecting boss on the polar plate and is not lower than 1/2 of the degree of the flow field connecting boss on the polar plate; more preferably, the height of the rib structure in the sealing groove is not lower than 3/4 of the height of the flow field connecting boss on the polar plate.

Furthermore, the width of a flow field connection boss on the polar plate is preferably 2-5mm; the height is preferably 0.25-0.4mm; the height of the rib structure in the sealing groove is preferably 0.2-0.4mm.

Further, the rib structure inside the sealing groove is provided with one or more, and more preferably one or two.

Further, the sealing structure further comprises a sealing groove outer reinforcing structure; preferably a reinforcement structure of a concave-convex design.

Further, the gap bridge region sealing structure further comprises a concave supporting structure inside the polar plate platform.

Further, the sealing element is completely attached to the rib structure in the sealing groove after the sealing element is compressed.

Has the beneficial effects that:

(1) The utility model discloses in through the bridge region and the design of gas vent district, reaction zone differentiation, set up different sealing member cross sectional parameter, promoted the height dimension in the regional sealing member cross-section of bridge, compensated the unsettled partial space of sealing member offside polar plate, guarantee that the sealing member has sufficient compression capacity, be favorable to promoting the regional polar plate leakproofness of bridge under certain pressure gas environment.

(2) In the sealing structure of the utility model, the middle sealing material of the sealing element does not bear the compression effect, which is helpful for reducing the assembly force of the galvanic pile and improving the reliability of the fastening piece of the galvanic pile; meanwhile, the sealing line made of the harder material can play a role in compressing and limiting the membrane electrode, the phenomenon that the membrane electrode is overvoltage to influence the performance and the service life of the galvanic pile is avoided, and the structure is favorable for uniformly distributing the assembly force of an active area and is favorable for ensuring the performance of the fuel cell.

(3) The total thickness of the harder middle layer sealing material and the solidified bonding materials of the surface layer and the bottom layer is fixed, the calculation can be carried out in advance, the gas with certain pressure can be sealed without calculating the compression rate and the filling rate of the sealing element during the design of the traditional sealing element, the size of the sealing element can be determined only by one parameter of the pitch distance after the single cells are pressed, the design is simpler, and the size can be better controlled during the assembly.

(4) The utility model discloses a boss additional strengthening along having increased the broad outside polar plate gas vent district, reaction zone seal groove has increased the intensity on the outer edge of polar plate seal groove, is favorable to guaranteeing the roughness of polar plate, increases the sealing reliability.

To sum up, through the utility model discloses a seal structure subregion design and the special layer material design of sealing member can solve the sealed inefficacy problem that traditional compression time arouses because material size, structure, reduces the design and the installation degree of difficulty, increases sealed reliability between fuel cell polar plate and the membrane electrode.

[ description of the drawings ]

FIG. 1 is a schematic view of a prior art rectangular cross-section seal structure

Fig. 2 (a) the utility model discloses seal structure partition design plan view, (b) the utility model discloses polar plate structure partition design plane schematic diagram

FIG. 3 is a partial schematic view of the polar plate structure of the reaction region of the present invention

FIG. 4 is a schematic cross-sectional view of the sealing structure between the gas inlet region and the reaction region of the present invention

FIG. 5 is a schematic cross-sectional view of a second sealing structure between the gas inlet region and the reaction region of the present invention

Fig. 6 is a schematic cross-sectional view of the sealing structure of the gap bridge area of the present invention

Fig. 7 is a schematic diagram of the structure of the bridge-crossing area electrode plate of the utility model

FIG. 8 is a schematic cross-sectional view of a third sealing structure of the gas port area and the reaction area of the present invention

Reference numerals

1. Membrane electrode frame, 2 traditional anode side sealing element, 2 'traditional cathode side sealing element, 3 anode side gas diffusion layer, 3' cathode side gas diffusion layer, 4 proton exchange membrane, 5 anode plate, 6 cathode plate, 7 hydrogen flow field, 8 air flow field, 9 coolant flow field, 10 pole plate outer edge boss, 11 flow field connection boss, 12 sealing groove, 13 the utility model discloses anode side sealing element intermediate layer, 13 'the utility model discloses cathode side sealing element intermediate layer, 14 anode side sealing element bottom layer, 14' cathode side sealing element bottom layer, 15. Anode side sealing element surface layer, 15 'cathode side sealing element surface layer, 16 air vent area, 17. Bridging area, 18. Reaction area, 19 sealing groove outer edge reinforcement structure, 20 sealing groove inner rib structure, 21. Flow field, 22 bridging area anode side sealing element intermediate layer, 22' bridging area sealing element intermediate layer, 23. Bridging area anode side sealing element surface layer, 23 'bridging area cathode side sealing element, 24 bridging area sealing element, 24' bridging area bottom layer, 25. Bridging area sealing element bottom layer, 26. Bridging area supporting platform inner side sealing element, 27. Platform supporting platform outer side platform sealing element, 27. Second platform sealing element, platform sealing area, platform inner side sealing element, platform sealing element, and platform sealing element outer edge reinforcement structure, 30

[ detailed description ] embodiments

To assist those skilled in the art to more accurately understand the technology of the present invention, embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

Referring to fig. 2, the three chambers of the fuel cell unit are designed to be divided into three different regions, namely, a gas vent region (16), a bridge region (17), and a reaction region (18), according to the geometric space of the three chambers.

As shown in fig. 5, which is a schematic view of a sealing structure between a gas port region and a reaction region, the sealing structure of a fuel cell includes a polar plate, a membrane electrode, and a sealing element located in a sealing groove of the polar plate, and the sealing element in the sealing groove is sealed after being cured, so that fuel, oxidant, and cooling medium flow in respective independent channels without mutual series or leakage. In order to highlight the technical key of the utility model, the utility model omits the specific structure drawing of the whole polar plate and the membrane electrode, and schematically draws the polar plate and the membrane electrode assembly which are close to the frame part of the membrane electrode. The polar plate comprises an anode plate (5) and a cathode plate (6), the membrane electrode is provided with a frame, a proton exchange membrane, a catalytic layer and a gas diffusion layer, and the gas diffusion layer comprises an anode side gas diffusion layer (3) and a cathode side gas diffusion layer (3'). The polar plate is outer along forming the polar plate along boss (10) outward through the punching press, and the polar plate is close to the flow field region and forms flow field connection boss (11) through the punching press, and the polar plate is outer along the space between boss and the flow field connection boss and constitutes the seal groove for it is sealed to hold sealing member, compression and reach the flow field. The utility model discloses in, through the experiment discovery, the width of flow field connection boss is 3mm, and highly the same is 0.4mm time sealed effect better with polar plate flow field height.

The sealing elements of the reaction zone and the gas port zone comprise an anode side sealing element and a cathode side sealing element, the anode side sealing element is positioned in the anode side sealing groove, the cathode side sealing element is positioned in the cathode side sealing groove, and the two sides of the membrane electrode are symmetrically arranged, as shown in fig. 5. The anode side sealing member comprises three layers of materials including a middle layer (13), a bottom layer (14) and a surface layer (15), and the cathode side sealing member comprises three layers of materials including a middle layer (13 '), a bottom layer (14 '), a surface layer (15 ')

The bridge region sealing structure is basically consistent with the internal shape design of the reaction region and air port region sealing structure, and is different from the reaction region and air port region sealing structures in that the sealing elements of the anode plate and the cathode plate are arranged in a staggered mode on two sides of the membrane electrode, as shown in figure 6. The anode plate (5) and the cathode plate (6) are punched and formed with sealing grooves (12), the anode side sealing element is positioned in the sealing groove (12) and corresponds to the gap bridge supporting platform (26) of the cathode plate (6), and the cathode side sealing element is positioned in the sealing groove (12) and corresponds to the gap bridge supporting platform (26) of the anode plate (5). The anode side seal member comprises three layers of materials including an intermediate layer (22), a bottom layer (24), and a surface layer (23), and the cathode side seal member comprises three layers of materials including an intermediate layer (22 '), a bottom layer (24 '), and a surface layer (23 '). In order to compensate the gap between the membrane electrode on the opposite side of the sealing element and the gap bridge supporting platform, the thickness of the middle layer of the sealing element in the gap bridge area is higher than that of the middle layer of the sealing element in the reaction area and the air port area.

The utility model discloses in, the intermediate level material of the seal structure in reaction zone, gas port district and gap bridge district is harder material, and shore hardness is 70-90, can be selected from EPDM, fluororubber etc.. The surface layer and the bottom layer are made of bonding materials, and can be selected from thermosetting type or normal temperature curing type materials, such as silica gel, thermoplastic resin and the like, so that the bonding materials are cured to achieve sealing, and the leakage of a flow field is blocked.

Through experiments, the sealing effect is best when the thickness ratio of the surface layer, the middle layer and the bottom layer is 1.

Experiments show that the contact width of the surface layer and the polar plate is at least 2mm, and the contact width of the bottom layer and the membrane electrode frame is at least 2mm. More preferably, the contact width of the surface layer and the polar plate is preferably 3.5mm, and the contact width of the bottom layer and the membrane electrode frame is preferably 2.5mm. Not only can play sealed effect this moment, can also play the spacing effect of installation bonding.

In this embodiment, the sealing member is a rectangular sealing member, the middle layer is made of EPDM with a thickness of 0.5mm, the surface layer and the bottom layer are made of thermosetting liquid silicone with a thickness of 0.05mm, the contact width between the surface layer and the polar plate is 3.5mm, and the contact width between the bottom layer and the membrane electrode frame is 2.5mm.

Alternately stacking the bipolar plates and the membrane electrodes provided with the three layers of sealing elements together, and mounting an end plate clamp; placing the stacked galvanic piles on a press, starting the press, and stopping pressing after the galvanic piles reach the expected height size and pressure; the stack was fastened using fasteners until the press pressure showed 0. Tests show that the galvanic pile sealing requirements are met, and the problems of flow field cross connection or external leakage of reaction media and cooling media do not exist.

In other embodiments, the bridge support platform (26) of the bridge region sealing structure is provided with an elongated recessed support (27) for supporting a gas flow passage with the back of the sealing groove. The height of the bridge supporting platform (26) is 0.4mm as high as that of the flow field boss. The width of the anode plate side sealing groove (12) is 5mm, the width of the gap bridge supporting platform (26) is 7mm, and an air inlet is formed in the right side of the platform. Correspondingly, the width of the other side cathode side gap bridge supporting platform is 7mm, the platform is also provided with a long strip-shaped sunken support (27), the width of the sealing groove (12) is 5mm, and the width of the outer side platform (28) of the gap bridge area sealing element is 3mm on the right side of the sealing groove. The ribs (20) in the sealing groove are 1mm wide and 0.3mm high. The cross-sectional structure of the sealing member (22') is the same as the length direction, the thickness is 0.6mm, and the thickness of the middle part is 0.3mm.

In another embodiment, the bottom of the sealing groove is provided with 1 sealing groove internal rib structure (20), the internal rib structure is integrally formed when the polar plate is subjected to punch forming, and the sealing installation and positioning can be realized through the design of the internal rib structure, so that the sealing reliability is improved.

The height and the width of the rib structure in the sealing groove meet the following requirements:

the height of the rib structure (19) in the sealing groove is not more than the height of the flow field connecting boss (11), is not less than 1/2 of the height of the flow field connecting boss (11), and is preferably not less than 3/4 of the height of the flow field connecting boss (11); the width of the rib structure (19) in the sealing groove meets the requirement that the length of a median line of the rib structure (19) in the sealing groove is 0.5-1mm;

the height of a polar plate flow field area is 0.4mm, the height of a flow field connecting boss (11) is 0.4mm, the height of a rib structure in a sealing groove is 0.3mm (0.1 mm lower than the flow field connecting boss), and the width is 0.6mm; the seal size was 3.9mm.

The sealing elements of the reaction area and the air port area are arranged in the sealing groove and symmetrically distributed on two sides of the frame of the membrane electrode, the bottom of each sealing element stretches across the rib structure in the sealing groove, the rib structure in the sealing groove is divided into a left first sealing part (29) and a right second sealing part (30), the first sealing part and the second sealing part are connected with each other, the first sealing part and the second sealing part are both formed by three layers of sealing materials, and the first sealing part and the second sealing part are rectangular.

In some embodiments, the seal is trapezoidal;

the utility model discloses a different regional seal structure of subregion design, cooperation sealing member multilayer material adopts the great sealing material of hardness and the bonding material cooperation of superficial layer, bottom, has solved the problem that the sealed easy inefficacy of compression in the past, has improved sealed reliability greatly, has reduced the design degree of difficulty.

The detailed description of the present invention is not provided for the purpose of describing the present invention by the prior art.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description of the present invention and to simplify the description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or to implicitly indicate the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally formed; may be mechanically coupled, may be electrically coupled or may be in communication with each other; they may be directly connected or indirectly connected through intervening media, or they may be interconnected within two elements or in a relationship where two elements interact with each other unless otherwise specifically limited. The specific meaning of the above terms in the present invention can be understood according to specific situations by those of ordinary skill in the art.

In the present disclosure, the terms "one embodiment," "some embodiments," "an example," "a specific example" or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art will understand that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications or substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims (13)

1. A fuel cell sealing structure is characterized by comprising a polar plate, a membrane electrode with a frame and a gas diffusion layer and a sealing element arranged in a sealing groove; the sealing structure is divided into a gas port area sealing structure, a gap bridge area sealing structure and a reaction area sealing structure, and an anode side sealing element and a cathode side sealing element in the gas port area sealing structure and the reaction area sealing structure are symmetrically arranged on two sides of the membrane electrode; the anode layer sealing element and the cathode side sealing element in the bridge region sealing structure are arranged on two sides of the membrane electrode in a staggered manner; the height of the sealing element in the bridge region sealing structure is greater than the height of the sealing element in the reaction region sealing structure and the sealing element in the gas port region sealing structure; the sealing element at least comprises a surface layer, a middle layer and a bottom layer; the middle layer is a sealing material with Shore hardness of 70-90, the surface layer and the bottom layer are bonding materials, the thickness ratio of the surface layer to the middle layer to the bottom layer is 1.

2. The sealing structure of claim 1, wherein the bridge area sealing structure has an anode side seal corresponding to the bridge support platform of the cathode plate and a cathode side seal corresponding to the bridge support platform of the anode plate.

3. The seal structure of claim 2, wherein the bridge support platform has a width that is no less than a width of the anode side and cathode side seals.

4. A sealing structure according to any one of claims 1 to 3, wherein the adhesive material of the surface layer and the base layer is selected from thermosetting type or ambient temperature curing type materials.

5. A sealing arrangement according to any of claims 1-3, wherein the interlayer material is selected from EPDM or viton.

6. A sealing arrangement according to any of claims 1 to 3, wherein the width of the surface layer in contact with the plate is at least 3.5mm and the width of the base layer in contact with the membrane electrode rim is at least 2.5mm.

7. A sealing arrangement according to any of claims 1 to 3, wherein the sealing member is trapezoidal or rectangular in shape.

8. The seal structure according to any one of claims 1 to 3, wherein the pole plate has a pole plate outer edge boss and a flow field connection boss, and a seal groove is formed between the pole plate outer edge boss and the flow field connection boss; the bottom of the sealing groove is provided with a sealing groove internal rib structure with the median line length of 0.5-1mm; the sealing element is arranged in the polar plate sealing groove, the bottom of the sealing element stretches across the rib structure in the sealing groove, and the top of the sealing element is in plane contact with the frame of the membrane electrode; and the rib structure in the sealing groove is matched with the sealing element, and the frame and the polar plate of the membrane electrode are compressed to form space sealing.

9. The seal structure of claim 8, wherein the rib structure inside the seal groove has a height not higher than the height of the flow field connection boss on the plate and not lower than 1/2 of the height of the flow field connection boss on the plate.

10. The seal structure of claim 9, wherein the rib structure height inside the seal groove is not less than 3/4 of the height of the flow field connection boss on the plate.

11. The seal structure of any one of claims 1-3, further comprising a seal groove outer reinforcement structure.

12. The seal structure of claim 11, wherein the seal groove outer reinforcement structure is a concavo-convex design reinforcement structure.

13. The seal structure of any of claims 1-3, wherein the bridge region seal structure further comprises a plate platform internal recess support structure.

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