Coating die head applied to heterogeneous cavity containing precious metal slurry

Abstract

The utility model relates to a coating die head applied to a heterogeneous cavity containing precious metal slurry, which comprises an upper die head, a lower die head and a gasket, the lower surface of the upper die head is clung to the upper surface of the lower die head, a gap at the clung position is a slurry coating channel, the upper die head and the lower die head are lips at the tail end of the slurry coating channel, and the gasket is arranged on the upper die head and the lower die head. A cavity used for containing slurry is formed in the surface, facing the slurry coating channel, of the upper die head, the depth and the width of the cavity are gradually reduced from the middle to the two sides, the two ends of the cavity are arc-shaped sections, a feeding hole and an exhaust hole are formed in the upper die head, and valves are arranged on the feeding hole and the exhaust hole respectively. According to the cavity structure disclosed by the utility model, the settling speed of slurry is greatly reduced, and the coating transverse consistency is improved.

Description

Technical Field

[0001] The utility model relates to a coating die head applied to a heterogeneous cavity containing precious metal slurry, belonging to the technical field of coating die heads. Background Art

[0002] According to the characteristics of hydrogen fuel cell slurry, the slurry is mainly composed of carbon powder slurry & catalyst (trace platinum or iridium oxide) and other solvents. Because the carbon powder slurry is mixed with precious metals, the sedimentation rate of the slurry is very amazing. Generally, the particles in the slurry will settle within 30 minutes or one hour. The slurry is an unstable suspension. As the slurry flows to the outlet, the particles will also sink due to their own gravity. In particular, the slower flow rate on both sides of the cavity is quite obvious, resulting in poor lateral consistency of the coating. Utility Model Content

[0003] In order to solve the above problems, the utility model discloses a coating die head applied to a heterogeneous cavity containing precious metal slurry, and its specific technical solution is as follows:

[0004] A coating die head applied to a heterogeneous cavity containing precious metal slurry, comprising an upper die head, a lower die head and a gasket, wherein the lower surface of the upper die head and the upper surface of the lower die head are in close contact, the gasket is located in the gap at the close contact, the back surfaces of the upper die head and the lower die head are connected by two rotatable connecting parts, the end positions of the upper die head and the lower die head on the coating side are lips, the surface of the upper die head facing the slurry coating channel is provided with a cavity for accommodating the slurry, the gap between the cavity and the lip is the slurry coating channel, the depth and width of the cavity gradually decrease from the middle to both sides, the two ends of the cavity are arc-shaped sections, the upper die head is provided with a feed hole and an exhaust hole, and the feed hole and the exhaust hole are respectively provided with valves.

[0005] Furthermore, the feed hole is located at the center of the cavity, and the feed hole is parallel to the slurry coating channel.

[0006] Furthermore, three exhaust holes are provided, which are respectively located at the center and two ends of the cavity, and the exhaust holes are perpendicular to the slurry coating channel.

[0007] Furthermore, the long side / short side of the cavity is 1.2 to 1.8, and the depth variation is: deep cavity / shallow cavity is 1.2 to 1.8.

[0008] Furthermore, the long side / short side of the cavity is 1.5, and the depth variation is: deep cavity / shallow cavity is 1.5.

[0009] Furthermore, the upper surface of the lower die head is tilted upward from the lip to the opposite side, with an inclination angle of 0 to 45 degrees, the lower surface of the upper die head is in contact with the upper surface of the lower die head, and the slurry coating channel is tilted downward by 0 to 45 degrees.

[0010] Furthermore, the upper surface of the lower die head is inclined upward from the lip to the opposite side, with an inclination angle of 22.43°, the lower surface of the upper die head is in contact with the upper surface of the lower die head, and the slurry coating channel is inclined downward by 22.43°.

[0011] Furthermore, the lips of the upper die head and the lower die head both extend forward with a pointed edge, and the width of the lips of the upper die head and the lower die head are both 0.35-1.00 mm.

[0012] Furthermore, the shape of the gasket is a "concave" shape, and the gasket surrounds both ends and the upper side of the slurry coating channel.

[0013] Furthermore, the cross-sectional width of the upper die head and the lower die head is greater than 380 mm, and the coating width is 380 mm.

[0014] The beneficial effects of the utility model are:

[0015] The utility model adopts a cavity as the upper mold, and the internal structure of the cavity is deep in the middle and shallow on both sides, wide in the middle and narrow on both sides. Through multiple cavity optimizations, the cavity profile of the utility model is finally obtained. At the same time, according to the simulation results, it can be seen that the optimized cavity greatly slows down the sedimentation rate of the slurry. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the utility model.

[0017] Figure 2 It is a side view of the utility model.

[0018] Figure 3 It is a perspective structural diagram of the utility model.

[0019] Figure 4 This is the slurry distribution diagram of the simulation test of the utility model.

[0020] List of reference numerals: 1—connecting piece, 2—upper die head, 3—end exhaust hole, 4—cavity, 5—middle exhaust hole, 6—feed hole, 7—pad, 8—lower die head, 9—upper die head lip, 10—lower die head lip, 11—gasket. DETAILED DESCRIPTION

[0021] The present invention is further described below in conjunction with the accompanying drawings and specific implementations. It should be understood that the following specific implementations are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0022] Combined with Figure 1-3 The structure of the utility model is introduced. The coating die head for heterogeneous cavity containing precious metal slurry comprises a connector 1, an upper die head 2, an end exhaust hole 3, a cavity 4, a middle exhaust hole 5, a feed hole 6, a pad 7, a lower die head 8, an upper die head lip 9, a lower die head lip 10 and a gasket 11. The upper die head 2 and the lower die head 8 are connected by two connectors 1. The upper die head 2 and the lower die head 8 are closely aligned. The closely aligned gap is the slurry coating channel. The end positions of the upper die head and the lower die head located in the slurry coating channel are lips. The surface of the upper die head facing the slurry coating channel is provided with a cavity 4 for accommodating the slurry. The depth and width of the cavity 4 gradually decrease from the middle to both sides. The upper die head is provided with a feed hole 6, and the feed hole 6 is located in the center of the cavity 4. The feed hole 6 is connected to the feed pipeline, and the feed pipeline is provided with a feed valve for controlling the switch and flow size of the slurry.

[0023] The feed hole 6 is parallel to the slurry coating channel. The parallel slurry flow direction is conducive to the slurry flowing evenly toward the slurry coating channel, which is conducive to the lateral uniformity of coating.

[0024] The upper die head 2 is also provided with three exhaust holes, which are located at the center and both ends of the cavity respectively. The exhaust holes located at the center are called middle exhaust holes 5, and the exhaust holes located at both ends are called end exhaust holes 3. The function of the exhaust holes is to discharge the bubbles in the slurry in the cavity 4 when starting, so as to ensure that the coating layer is uniform in thickness and has no aeration points. An exhaust valve is provided on the exhaust hole 3. When there are no bubbles in the slurry discharged from the exhaust hole 3, the exhaust valve is closed, and the slurry is sprayed from the slurry coating channel through the lip position onto the material to be coated.

[0025] The vent hole is perpendicular to the slurry coating channel. This perpendicular angle allows the gas in the slurry to be discharged from the vent hole after the slurry fills the entire cavity 4, while ensuring that the slurry in the cavity 4 is in a full state.

[0026] The long side / short side of the cavity = 1.5, and the depth variation: deep cavity / shallow cavity = 1.5. The upper surface of the lower die head is tilted upward from the lip to the opposite side, with an inclination angle of 22.43°. The lower surface of the upper die head fits the upper surface of the lower die head, and the slurry coating channel is tilted downward by 22.43°. The lip width of the upper and lower die heads is 0.35mm. This structure is selected after multiple optimizations, and it has been verified through experiments that the structural proportion and lateral uniformity of the coating are the best.

[0027] The lips of the upper die and the lower die both extend forward with a pointed edge. The pointed edge of the lips is conducive to the spraying of the slurry and is convenient for adjusting the distance between the lips and the material to be coated.

[0028] The utility model takes the inlet flow rate in the slurry feed hole as 3.8mL / s, the coating speed as 6m / min, the thickness of the gasket as 0.1mm, and the knife distance GAP (the knife distance is the distance from the lip to the foil) as 100μm as an example to simulate and test the coating process of the slurry coating channel with different inclination angles.

[0029] See also Figure 4 , Figure 4 The red area in the figure is the slurry area. After the slurry fills the cavity, the gas in the slurry is discharged, and the coating speed of the slurry is stabilized, the subsequent pressure distribution, slurry streamlines, and particle concentration distribution simulations are performed.

[0030] The coating process parameters of the simulation state are shown in Table 1 below.

[0031] Table 1

[0032] Parameters at a glance

[0033] Serial number Coating process parameters unit Remark 1 Single row coating width 380 mm 2 Solid content of coating liquid 5％ - 3 Coating liquid density 1000 <![CDATA[kg / m 3 ]]> 4 Viscosity 1 Pa·s 5 Coating dry film thickness 5 μm Single side thickness 6 Coating wet film thickness 100 μm Single side thickness 7 Coating speed 6 m / min - 8 Surface tension N / m 9 Contact Angle Contact angle between slurry and substrate 10 Particle size 1.0 μm

[0034] The coating liquid in Table 1 is the slurry.

[0035] The simulation test results are summarized in Table 2.

[0036] Table 2

[0037]

[0038] Based on the above comprehensive evaluation, this patent selects an example in which the inclination angle of the feed hole and the slurry coating channel to the horizontal plane is 0 to 45° as the optimized structure of the utility model, among which 22.43° is the optimal inclination angle.

[0039] The term “connection” as used in this application may mean a direct connection between components or an indirect connection between components via other components.

[0040] With the above-mentioned ideal embodiments of the present invention as inspiration, through the above-mentioned description content, relevant staff can make various changes and modifications without departing from the scope of the technical idea of ​​the present invention.

Claims

1. A coating die head for a heterogeneous cavity containing precious metal slurry, comprising an upper die head, a lower die head and a gasket, wherein the lower surface of the upper die head and the upper surface of the lower die head are in close contact, and the gasket is located in the gap at the close contact, and the backs of the upper die head and the lower die head are connected by two rotatable connecting parts, and the end positions of the upper die head and the lower die head on the coating side are lips, characterized in that: A cavity for accommodating the slurry is provided on the surface of the upper die head facing the slurry coating channel, and the gap between the cavity and the lip is the slurry coating channel. The depth and width of the cavity gradually decrease from the middle to both sides, and the two ends of the cavity are arc-shaped cross-sections. A feed hole and an exhaust hole are provided on the upper die head, and the feed hole and the exhaust hole are respectively provided with valves.

2. The coating die head for a heterogeneous cavity containing precious metal slurry according to claim 1, characterized in that: The feed hole is located at the center of the cavity, and the feed hole is parallel to the slurry coating channel.

3. The coating die head for a heterogeneous cavity containing precious metal slurry according to claim 1, characterized in that: There are three exhaust holes, which are respectively located at the center and two ends of the cavity, and the exhaust holes are perpendicular to the slurry coating channel.

4. The coating die head for a heterogeneous cavity containing precious metal slurry according to claim 1, characterized in that: The long side / short side of the cavity is 1.2 to 1.8, and the depth variation is: deep cavity / shallow cavity is 1.2 to 1.

8.

5. The coating die head for a heterogeneous cavity containing precious metal slurry according to claim 1, characterized in that: The long side / short side of the cavity is 1.5, and the depth variation is: deep cavity / shallow cavity is 1.

5.

6. The coating die head for a heterogeneous cavity containing precious metal slurry according to claim 1, characterized in that: The upper surface of the lower die head is tilted upward from the lip to the opposite side, with an inclination angle of 0 to 45 degrees. The lower surface of the upper die head is in contact with the upper surface of the lower die head, and the slurry coating channel is tilted downward by 0 to 45 degrees.

7. The coating die head for a heterogeneous cavity containing precious metal slurry according to claim 1, characterized in that: The upper surface of the lower die head is tilted upward from the lip to the opposite side, with an inclination angle of 22.43°. The lower surface of the upper die head is in contact with the upper surface of the lower die head, and the slurry coating channel is tilted downward by 22.43°.

8. The coating die head for a heterogeneous cavity containing precious metal slurry according to claim 1, characterized in that: The lips of the upper die head and the lower die head both extend forward to form a pointed edge, and the lip widths of the upper die head and the lower die head are both 0.35-1.00 mm.

9. The coating die head for a heterogeneous cavity containing precious metal slurry according to claim 1, characterized in that: The shape of the gasket is a "concave" shape, and the gasket surrounds the two ends and the upper side of the slurry coating channel.

10. The coating die head for a heterogeneous cavity containing precious metal slurry according to claim 1, characterized in that: The horizontal widths of the upper die head and the lower die head are greater than 380 mm, and the coating width is 380 mm.

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