Vacuum Coating Device

Abstract

The present invention discloses a vacuum coating device, comprising: a crucible; an induction heater provided on the periphery of the crucible; a flow distribution box connected to the top of said crucible via a steam pipe. Wherein said flow distribution box is provided inside with a horizontal pressure stabilizing plate, said flow distribution box is connected on the top with a nozzle, said steam pipe is provided with a pressure regulating valve, and said pressure stabilizing plate has a multi-hole structure. The lower surface of said pressure stabilizing plate is connected to a horizontal flow suppression plate, and a space is formed between the side of said flow suppression plate and the inner wall of said flow distribution box. A jet moderating zone is formed between the joint where said flow distribution box and said steam pipe are connected and the lower surface of said pressure stabilizing plate, and a jet accelerating zone is formed between the upper surface of said pressure stabilizing plate and the joint where said flow distribution box and said nozzle are connected. When the high-temperature steam reaches the low-temperature steel plate, a uniform coating can be formed on the steel plate surface.

Claims

1. A vacuum coating device, comprising: a crucible; an induction heater provided on the periphery of the crucible; a flow distribution box connected to the top of said crucible via a steam pipe, wherein said flow distribution box is provided inside with a horizontal pressure stabilizing plate, said flow distribution box is connected on the top with a nozzle, said steam pipe is provided with a pressure regulating valve; said pressure stabilizing plate has a multi-hole structure, the lower surface of said pressure stabilizing plate is connected to a horizontal flow suppression plate, and a space is formed between the side of said flow suppression plate and the inner wall of said flow distribution box; a jet moderating zone is formed between the joint where said flow distribution box and said steam pipe are connected and the lower surface of said pressure stabilizing plate, and a jet accelerating zone is formed between the upper surface of said pressure stabilizing plate and the joint where said flow distribution box and said nozzle are connected.

2. The vacuum coating device of claim 1, wherein said pressure stabilizing plate has a T-shaped section, the ends along the horizontal direction of said pressure stabilizing plate are connected to the inner wall of said flow distribution box, and the end along the vertical direction of said pressure stabilizing plate is connected to said flow suppression plate.

3. The vacuum coating device of claim 2, wherein said flow suppression plate is rectangular, a space D between one pair of opposite sides of said flow suppression plate and the inner walls of said flow distribution box is 0.1˜5 mm.

4. The vacuum coating device of claim 1, wherein the ratio of the volume of the jet moderating zone V1 to the volume of the jet accelerating zone V2 is 1˜5.

5. The vacuum coating device of claim 1, wherein the holes in said pressure stabilizing plate are rectangular, circle or triangular in shape, and run in linear, curvilinear direction or have a multilayer structure.

6. The vacuum coating device of claim 5, wherein said nozzle has a nozzle outlet, the ratio of the total area of holes on said pressure stabilizing plate S.sub.holes to the area of said nozzle outlet S.sub.outlet is 0.1 or more, that is, S.sub.holes/S.sub.outlet≥0.1.

7. The vacuum coating device of claim 6, wherein said nozzle outlet is of a slit shape or multi-hole, and the ratio of the area of said nozzle outlet Soutlet to the area of the joint between said steam pipe and the top of said crucible S.sub.inlet is 0.05˜5.

8. The vacuum coating device of claim 7, wherein said nozzle outlet is of a linear slit or a curvilinear slit.

9. The vacuum coating device of claim 3, wherein the ratio of a space between the other pair of opposite sides of said flow suppression plate to the length of the inner wall of the flow distribution box is 0.1˜0.4.

10. The vacuum coating device of claim 7, wherein said nozzle is made of graphite, ceramic or metal.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] FIG. 1 is a schematic diagram of application BE1009321A6;

[0031] FIG. 2 is a schematic diagram of application BE1009317A61;

[0032] FIG. 3 is a schematic diagram of application JPS59177370A;

[0033] FIG. 4 is a schematic diagram of application U.S. Pat. No. 4,552,092A;

[0034] FIG. 5 is a schematic diagram of application WO2018/020311A1;

[0035] FIG. 6 is a schematic diagram of application CN103249860A;

[0036] FIG. 7 is a schematic diagram of application CN101175866A;

[0037] FIG. 8 is a schematic diagram of the square shell in FIG. 7;

[0038] FIG. 9 is a cutaway view of the vacuum coating device of the present invention in the width direction;

[0039] FIG. 10 is a cutaway view of the flow distribution box in the vacuum coating device of FIG. 9 in the length direction;

[0040] FIG. 11 is a schematic diagram of the distribution of the zones in the vacuum coating device of FIG. 9 (width direction); and

[0041] FIG. 12 is a schematic diagram of the area classification of parameters in the vacuum coating device of FIG. 9 (width direction).

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0042] The technical solutions of the present invention are further described below with reference to the accompanying drawings and embodiments.

[0043] Referring to FIG. 9 to FIG. 12, the present invention provides a vacuum coating device. The vacuum coating device comprises a crucible 13. The crucible 13 contains molten metal 14. An induction heater 15 is arranged on the periphery of the crucible 13. The top of the crucible 13 is connected to a flow distribution box 17 via a steam pipe 16. A pressure regulating valve 18 is arranged in steam pipeline 16. A horizontal pressure stabilizing plate 19 is arranged in said flow distribution box 17. Said pressure stabilizing plate 19 has a T-shaped section, the ends along the horizontal direction of said pressure stabilizing plate 19 are connected to the inner wall of said flow distribution box 17, the end along the vertical direction of said pressure stabilizing plate 19 is connected to a flow suppression plate 20. The top of the flow distribution box 17 is connected to a nozzle 21.

[0044] Preferably, said pressure stabilizing plate 19 has multi-hole structure, and the holes in said pressure stabilizing plate can be in various shapes, such as rectangular, circle or triangular. Those holes run in linear, curvilinear direction or have a multilayer structure. The ratio of the total area of holes on said pressure stabilizing plate 19 S.sub.holes to the area of said nozzle outlet Soutlet is 0.1 or more, and is 10 or less simultaneously, that is, 0.1≤S.sub.holes/S.sub.outlet≤10.

[0045] Preferably, a jet moderating zone is formed between the joint where said flow distribution box 17 and said steam pipe 16 are connected (that is, the inlet of the flow distribution box 17, the area of the joint is denoted as S.sub.inlet) and the lower surface of said pressure stabilizing plate 19, the volume of the jet moderating zone is V1. A jet accelerating zone is formed between the upper surface of said pressure stabilizing plate 19 and the joint where said flow distribution box 17 and said nozzle 21 are connected (that is, the outlet of the flow distribution box 17), the volume of the jet accelerating zone is V2.

[0046] Preferably, said flow suppression plate 20 is also arranged in the horizontal direction, a space between one pair of opposite sides of the flow suppression plate (the pair of opposite sides along the width direction in FIG. 9) and the inner walls of said flow distribution box 17 is D. The flow suppression plate 20 can be in various shapes, such as rectangular, circular, triangular, trapezoidal, etc., its main function is to redistribute the steam from the steam pipe 16 into the jet moderating zone. The redistributed steam enters the pressure stabilizing plate 19 and then enters the jet accelerating zone through the holes of the pressure stabilizing plate 19, thus indirectly extending the movement path of the steam and achieving a quite uniform distribution before entering the pressure stabilizing plate 19.

[0047] Preferably, said nozzle 21 has a nozzle outlet, said nozzle outlet is of a slit shape or multi-hole. Nozzle outlet is of a linear slit or a curvilinear slit, and the multi-hole type outlet is rectangular, round or trapezoidal in shape. The ratio of the area of nozzle outlet to the area of a joint of the top of crucible is 0.05˜5.

[0048] Preferably, said nozzle 21 operates with an internal pressure of 500˜500,000 Pa.

[0049] Preferably, said nozzle 21 is made of graphite, ceramic or inert metals, as well as other materials that can be processed.

[0050] Preferably, said molten metal 14 contains metals such as zinc, magnesium, aluminum, tin, nickel, copper, iron, etc., in addition to low melting point (below 2000° C.) oxides of these metals.

[0051] Preferably, the steel plate 100 is cleaned by plasma or other devices before vacuum coating, and the preheating temperature reaches 80˜300° C.

[0052] The specific steps for using the vacuum coating device of the present invention are as follows.

[0053] 1) Solid metal is melted into molten metal 14 in the crucible 13 by the induction heater 15, and then the molten metal 14 begins to vaporize at a high overheat temperature and low pressure, gradually forming the metal steam 22.

[0054] 2) In the beginning phase, the pressure regulating valve 18 arranged in the steam pipe 16 connected to the crucible 13 is closed. As the molten metal 14 continuously vaporizes, the steam pressure of an inner chamber of the crucible 13 continuously increases. When the inner chamber of the crucible 13 reaches a certain pressure (for example, 5000˜500,000 Pa), the pressure regulating valve 18 is opened to ensure constant pressure output. Meanwhile, the power of the induction heater 15 is increased to compensate for the reduced pressure due to the opening of the pressure regulating valve 18; and the power range of the induction heater 15 is adjusted to keep the pressure of the inner chamber of the crucible 13 to be within a certain range.

[0055] 3) After the pressure regulating valve 18 is opened, the metal steam 22 flows along the steam pipeline 16. When entering into the flow distribution box 17, due to the restriction of the flow suppression plate 20, the original direction of steam flowing out of the steam pipe is changed, with most of the steam distributing from both sides of the flow suppression plate 20 (the periphery of the flow suppression plate in the length direction, see FIG. 10), and there is another part of the steam passing through the flow control zone 23 (that is, the periphery of the flow suppression plate in the width direction, see FIG. 9) into the jet moderating zone.

[0056] After that, the pressure of the high-velocity stream formed by the metal steam is reduced due to the restriction of the pressure stabilizing plate 19. And the steam flows uniformly along the holes in the pressure stabilizing plate 19 and subsequently flows uniformly from the nozzle at the top of the flow distribution box 17.

[0057] 4) Due to the narrow outlet of the nozzle, the metal steam 22 flows out at a large speed. At this time, a moving steel plate 100 is arranged above the nozzle outlet, the temperature of the metal steam 22 is high, when the metal steam reaches the low-temperature steel plate 100, it solidifies rapidly, forming a metal coating 24.

Embodiment

[0058] The steel plate 100 is galvanized, and the width of the steel plate 100 is 1,000 mm. After cleaning and drying, the steel plate 100 is heated to 120° C. Zinc on steel plate surface is vaporized by the induction heater 15, and then adjust the power of the induction heater to raise the pressure in the crucible 13 to 20,000 Pa, and the pressure regulating valve 18 is closed before that. When the pressure in the crucible 13 reaches 20,000 Pa, the pressure regulating valve 18 is opened, and then the metal steam 22 enters into the flow distribution box 17 through the steam pipe 16. The flow suppression plate 20 is rectangular, wherein V1/V2=2, D=1 mm. The pressure stabilizing plate 19 has multi-hole structure, S.sub.holes/S.sub.outlet=3, the pressure in nozzle 21 is 5,000 Pa. The nozzle 21 is made of graphite, and the nozzle outlet is of a rectangular slit. S.sub.outlet/S.sub.inlet=0.95.

[0059] Those of ordinary skill in the art should realize that the above embodiments are only used to illustrate the present invention, but not used to limit the present invention. Changes and modifications made to the above embodiments without departing from the essential spirit scope of the present invention shall all fall within the scope of the claims of the present invention.