Gasket for slit direct coating

Abstract

The utility model discloses a gasket for slit direct coating, which can reliably discharge bubbles in slurry, ensure that a coating formed by the slurry is good in thickness uniformity, and ensure that the coating is good in appearance and not easy to dry and crack subsequently. The base plate comprises a base plate body, a feeding opening is formed in one end of the base plate body in the length direction, the feeding opening is used for being communicated with an injection molding material opening of an upper mold, the feeding opening is connected with an exhaust transition flow channel, and a plurality of side protruding exhaust outlet flow channels are arranged on the two sides of the exhaust transition flow channel in the length direction respectively. The tail ends of the exhaust outlet flow channels in the length direction are connected with corresponding exhaust channels of an upper die respectively, the tail end of the exhaust transition flow channel is connected with a first flow dividing flow channel, the first flow dividing flow channel is arranged towards an opening in one side to form a flow channel outlet, and N groups of flow dividing flow channels are arranged on the base plate body at intervals in the length direction. Each group of shunting flow channels are arranged at intervals through spacing teeth, and flow channel outlets of all the shunting flow channels face the same direction.

Description

Technical Field

[0001] The utility model relates to the technical field of membrane electrode manufacturing, in particular to a gasket for slit direct coating. Background Technique

[0002] In the preparation of the fuel cell membrane electrode coating, when the existing slit coating technology is adopted, the slurry flows through the transfer path formed by the gasket through the upper die injection port, and then in the flow channels of the lower die of the transfer path shunt channels. In the actual process, the coating appearance is not good, there are bubbles in the slurry, and the thickness uniformity of the coating is difficult to guarantee, which further leads to the problem that the coating is prone to cracking, seriously affecting the performance and quality of the fuel cell membrane electrode.

[0003] After analysis, it is found that the bubbles in the slurry are not easy to be discharged, which further leads to the difficulty in ensuring the thickness uniformity of the coating formed by the slurry, resulting in the subsequent cracking of the coating, and due to the difficulty in discharging the bubbles, the coating appearance is not good. Therefore, it is urgent to solve the technical problem of discharging the bubbles in the slurry. Summary of the Invention

[0004] Aiming at the above problems, the utility model provides a gasket for slit direct coating, which can reliably discharge the bubbles in the slurry, ensure good thickness uniformity of the coating formed by the slurry, and ensure good appearance of the coating and not easy to crack subsequently.

[0005] A gasket for slit direct coating, characterized in that: it includes a backing plate body, one end of the backing plate body in the length direction is provided with a feed port, the feed port is used to communicate with the injection port of the upper die, the feed port is connected with an exhaust transition flow channel, and both sides of the length direction of the exhaust transition flow channel are respectively provided with a plurality of side convex exhaust outlet flow channels, the ends of the length direction of the exhaust outlet flow channels are respectively connected with the corresponding exhaust channels of the upper die, the end of the exhaust transition flow channel is connected with a first shunt flow channel, the first shunt flow channel is arranged with an opening towards one side to form a flow channel outlet, the backing plate body is provided with N groups of shunt flow channels at intervals along the length direction, N is a natural number, each group of shunt flow channels is arranged at intervals by spacer teeth, the flow channel outlets of all shunt flow channels face the same direction, and a return flow channel arranged along the length direction is further provided at the inner end of the shunt flow channel at the end, and the end of the return flow channel is connected with the discharge port on the upper die.

[0006] It is further characterized in that:

[0007] The starting end faces of the inner ends of the N groups of shunt flow channels are arranged flush, and all the starting end faces are flush with the first end edge of the exhaust transition flow channel, ensuring that the starting end faces of the surface regions of all the shunt flow channels corresponding to the flow channels of the upper die and the lower die are the same, so that the pressure of the slit direct coating is the same;

[0008] The four corners of the backing plate body are respectively provided with first positioning holes, and the upper die, the backing plate body and the lower die are fixedly connected through corresponding fasteners;

[0009] A set of positioning connection hole groups are arranged at one end of the backing plate body in the length direction away from the runner outlet, and the positioning connection hole groups are used for reliable fastening connection of the upper die, the backing plate body and the lower die;

[0010] The positioning connection hole group includes a pair of first auxiliary positioning holes and second auxiliary positioning holes respectively arranged on both sides of the backing plate body in the length direction. The first auxiliary positioning hole is used for aligning with a first convex column preset on the lower die, and the second auxiliary positioning hole is used for aligning with a second convex column preset on the lower die, which is used for pre-assembly positioning of the gasket body to ensure quick and convenient assembly;

[0011] The first auxiliary positioning hole is a round hole, and the second auxiliary positioning hole is an oblong hole arranged along the length direction of the backing plate body. The first auxiliary positioning hole is the reference hole, and the second auxiliary positioning hole makes the structure have a small manufacturing error, reducing the manufacturing precision of the whole mold in the length direction and ensuring the reduction of manufacturing cost;

[0012] Outer convex handles are respectively arranged at both ends of the backing plate body in the length direction. Since the backing plate body is very thin, it is not easy to take out from the upper die and the lower die without making handles;

[0013] The ends of the spaced teeth are provided with micro-arc chamfers corresponding to the positions of the two sides of the runner outlet;

[0014] The backing plate body is respectively provided with micro-arc chamfers corresponding to the positions of the first runner outlet and the Nth runner outlet;

[0015] The radius of the micro-arc chamfer is 0.1 mm to 0.3 mm, which makes the slurry flow out more smoothly, reduces turbulence or blockage phenomena, and thus improves the appearance flatness of the coating.

[0016] After adopting the above technical solution, the slurry first flows into the exhaust transition runner from the feed port before entering the N-component flow runner. Since the exhaust transition runner has exhaust outlet runners on both sides, the volume corresponding to the whole exhaust transition runner is larger than that of the previous runner, so that the flow rate of the slurry passing through the exhaust transition runner becomes relatively slower. The bubbles in the slurry can gather in the exhaust transition runner and be discharged outwards from the exhaust outlet runner, and finally be discharged through the corresponding exhaust channels of the upper die. It can reliably discharge the bubbles in the slurry, ensure good uniformity of the coating thickness formed by the slurry, and ensure good appearance of the coating and not easy to crack subsequently. Description of the Drawings

[0017] Figure 1 It is a schematic front view structure diagram of the present invention;

[0018] Figure 2 Schematic diagram of the application of the present utility model to a slot coating die;

[0019] The names corresponding to the serial numbers in the figure are as follows:

[0020] Feeding port 1, exhaust transition flow channel 2, first end edge 201, exhaust outlet flow channel 3, end in the length direction 301, shunt flow channel 4, starting end face 401, first shunt flow channel 41, first flow channel outlet 411, second shunt flow channel 42, third shunt flow channel 43, fourth shunt flow channel 44, fourth flow channel outlet 441, spacer teeth 5, micro-arc chamfer 51, return flow channel 6, outward convex handle 7, positioning connection hole group 8, first auxiliary positioning hole 81, second auxiliary positioning hole 82, backing plate body 10, first positioning hole 101, upper die 20, plastic injection port 21, exhaust channel 22, lower die 30, discharge flow channel 31. Specific implementation mode

[0021] A gasket for slot direct coating, see Figure 1 and Figure 2 : It includes a backing plate body 10. One end in the length direction of the backing plate body 10 is provided with a feeding port 1, and the feeding port 1 is used to communicate with the plastic injection port 21 of the upper die 20. The feeding port 1 is connected to an exhaust transition flow channel 2. On both sides in the length direction of the exhaust transition flow channel 2, a plurality of side convex exhaust outlet flow channels 3 are respectively arranged. The ends 301 in the length direction of the exhaust outlet flow channels 3 are respectively connected to the corresponding exhaust channels 22 of the upper die 20. The end of the exhaust transition flow channel 2 is connected to a first shunt flow channel 41. The first shunt flow channel 41 is arranged to open towards one side and form a first flow channel outlet 411. The backing plate body 10 is provided with N groups of shunt flow channels at intervals along the length direction. Each group of shunt flow channels is spaced by spacer teeth 5. The flow channel outlets of all the shunt flow channels 4 face the same direction. The inner end of the shunt flow channel 4 at the end is also provided with a return flow channel 6 arranged along the length direction. The end of the return flow channel 6 is connected to the discharge flow channel 31 on the lower die 30.

[0022] During specific implementation, the flatness of the gasket body is controlled within 5 μm to accurately control the uniform distribution of the slurry; according to the flow characteristics of the slurry and the requirements of the coating thickness, the gasket divides the slot flow channel into N groups of shunt flow channels. During specific implementation, the width of each section of the shunt flow channel 4 is the same, and it can coat multiple products simultaneously, achieving the effect of multi-channel simultaneous coating, improving production efficiency and ensuring the uniformity of the coating thickness.

[0023] In a specific embodiment, the value of N is 4;

[0024] The starting end faces at the inner ends of the 4 groups of shunt flow channels 4 are arranged flush. The 4 groups of shunt flow channels are respectively the first shunt flow channel 41, the second shunt flow channel 42, the third shunt flow channel 43, and the fourth shunt flow channel 44;

[0025] The starting end faces 401 of all the four-component flow channels are arranged flush with the first end edge 201 of the exhaust transition flow channel 2, ensuring that the starting end faces of the areas corresponding to the flow channels of the upper die 20 and the lower die 30 for all the flow channels 4 are the same, so that the pressure of slit direct coating is the same;

[0026] First positioning holes 101 are respectively arranged at the four corner positions of the backing plate body 10, and the upper die 20, the backing plate body 10, and the lower die 30 are fixedly connected by corresponding fasteners;

[0027] A set of positioning connection hole groups 8 are arranged at one end of the backing plate body 10 in the length direction away from the flow channel outlet, and the positioning connection hole groups 8 are used for reliable fastening connection of the upper die 20, the backing plate body 10, and the lower die 30;

[0028] The positioning connection hole group 8 includes a pair of first auxiliary positioning holes 81 and second auxiliary positioning holes 82 respectively arranged in the areas on both sides of the backing plate body in the length direction. The first auxiliary positioning hole 81 is used for aligning with the first raised column preset on the lower die 30, and the second auxiliary positioning hole 82 is used for aligning with the second raised column preset on the lower die 30. It is used for pre-assembly positioning of the gasket body 10 to ensure quick and convenient assembly;

[0029] The first auxiliary positioning hole 81 is a round hole, and the second auxiliary positioning hole 82 is an oblong hole arranged along the length direction of the backing plate body 10. The first auxiliary positioning hole 81 is the reference hole. The second auxiliary positioning hole 82 makes the structure have a slight manufacturing error, reducing the manufacturing precision of the whole die in the length direction and ensuring the reduction of manufacturing cost;

[0030] Outer convex handles 7 are respectively arranged at both ends of the backing plate body 10 in the length direction. Since the backing plate body 10 is very thin, if the outer convex handles 7 are not made, it is not easy to take out from the upper die 20 and the lower die 30. In the closed die state, the outer convex handles 7 protrude from the corresponding vertical surfaces of the upper die 20 and the lower die 30;

[0031] At the end of the spaced teeth 5, micro-arc chamfers 51 are arranged corresponding to the positions of the flow channel outlets on both sides;

[0032] Micro-arc chamfers 51 are respectively arranged at the positions of the backing plate body 10 corresponding to the first flow channel outlet 411 and the fourth flow channel outlet 441;

[0033] The radius of the micro-arc chamfer 51 is 0.1 mm to 0.3 mm. During manufacturing, laser cutting burr removal operations are performed at all openings to ensure no burrs. It makes the slurry flow out more smoothly, reducing turbulence or blockage phenomena, thereby improving the appearance flatness of the coating.

[0034] In specific implementation, the gasket body is made of 316L stainless steel material, which plays an insulating and guiding role in the upper and lower flow channels of the slot coater, preventing the sealing ring from blocking the flow channel due to the over-tightening of the coater; 316L stainless steel not only has a high-strength supporting effect, but also has excellent chemical stability, can resist the erosion of chemical substances in the fuel cell working environment, and extends the service life of the gasket.

[0035] Its beneficial effects are as follows: significantly improving the appearance quality of the coating, making the surface of the coating more flat and smooth; effectively removing the bubbles in the slurry, improving the density and electrochemical performance of the coating; precisely controlling the coating thickness, ensuring the consistency and stability of the membrane electrode performance; greatly reducing the probability of uneven thickness distribution during the coating process, and extending the service life of the membrane electrode.

[0036] For those skilled in the art, it is obvious that the present utility model is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present utility model. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present utility model is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present utility model. Any reference signs in the claims should not be regarded as limiting the claimed claim.

[0037] In addition, it should be understood that although this specification is described according to the embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A gasket for slit direct coating, characterized in that: It includes a pad body, one end of the pad body in the length direction is provided with a feed port, the feed port is used to connect to the injection port of the upper mold, the feed port is connected to the exhaust transition flow channel, and a plurality of side convex exhaust outlet flow channels are respectively provided on both sides of the length direction of the exhaust transition flow channel, the ends of the exhaust outlet flow channels in the length direction are respectively connected to the corresponding exhaust channels of the upper mold, the ends of the exhaust transition flow channels are connected to the first diversion flow channel, the first diversion flow channel is arranged to open to one side to form a flow channel outlet, the pad body is provided with N groups of diversion flow channels at intervals along the length direction, N is a natural number, each group of diversion flow channels is arranged by spacing teeth, the flow channel outlets of all diversion flow channels are in the same direction, the inner end of the diversion flow channel located at the end is also provided with a return flow channel arranged along the length direction, and the end of the return flow channel is connected to the discharge port on the upper mold.

2. A slit direct coating gasket according to claim 1, characterized in that: The inner end starting end faces of the N groups of diverter flow channels are all arranged flush, and all starting end faces are arranged flush with the first end edges of the exhaust transition flow channels, ensuring that the starting end faces of all diverter flow channels corresponding to the surface area intervals of the flow channels of the upper mold and the lower mold are the same.

3. A slit direct coating gasket according to claim 1, characterized in that: The four corners of the backing plate body are respectively provided with first positioning holes, and the upper mold, the backing plate body and the lower mold are fixedly connected by corresponding fasteners.

4. A slit direct coating gasket according to claim 3, characterized in that: A group of positioning connection holes is arranged at one end of the pad body in the length direction away from the flow channel outlet.

5. A slit direct coating gasket according to claim 4, characterized in that: The positioning connection hole group includes a pair of first auxiliary positioning holes and second auxiliary positioning holes arranged on both sides of the length direction of the gasket body. The first auxiliary positioning hole is used to align the first protruding column preset on the lower mold, and the second auxiliary positioning hole is used to align the second protruding column preset on the lower mold, which is used for pre-installation positioning of the gasket body.

6. A slit direct coating gasket according to claim 5, characterized in that: The first auxiliary positioning hole is a round hole, and the second auxiliary positioning hole is a waist-shaped hole arranged along the length direction of the pad body.

7. A slit direct coating gasket according to claim 1, characterized in that: Outwardly protruding handles are respectively arranged at both ends of the pad body in the length direction.

8. The slit direct coating gasket according to claim 1, characterized in that: The ends of the spacing teeth are provided with micro-arc chamfers corresponding to the flow channel outlets on both sides.

9. A slit direct coating gasket according to claim 8, characterized in that: The pad body is provided with micro-arc chamfers at positions corresponding to the first flow channel outlet and the Nth flow channel outlet.

10. A slit direct coating gasket according to claim 8 or 9, characterized in that: The radius of the micro-arc chamfer is 0.1 mm to 0.3 mm.

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