JP7019467B2 - Seal structure and sealing method - Google Patents

Description

The present invention relates to a sealing structure and a sealing method.

In various devices using vacuum such as a vacuum vapor deposition device, a seal structure in which a flange and a metal gasket are combined is used for attaching and connecting a lid, a pipe, or the like. In particular, in a vacuum device, a seal structure having a knife-edge type flange is widely used (see Patent Documents 1 and 2).

FIG. 5 shows the conventional seal structure 30. In the conventional knife edge type flanges 31a and 31b, annular knife edges 34a and 34b are formed on the sealing portions 33a and 33b. The knife edges 34a and 34b usually have a protrusion shape with an acute cross section. Further, outer frames 35a and 35b are provided on the outside of the seal portions 33a and 33b. When the pair of flanges 31a and 31b are butted and joined, an annular metal gasket 32 is arranged between the sealing portions 33a and 33b. The flanges 31a and 31b are usually fixed by bolts or the like (not shown), and in the process of being tightened in the vertical direction in FIG. 5, the knife edges 34a and 34b bite into the metal gasket 32 as shown in FIG. .. Along with this bite, the metal gasket 32 is plastically deformed and bulges outward, so that the outer peripheral surface 38 of the metal gasket 32 is pressed against the inner surfaces of the outer frames 35a and 35b of the flanges 31a and 31b. As described above, in the seal structure 30 having the conventional knife edge type flange, the metal gasket 32 is pressed from the upper and lower sides and the outside (knife edges 34a, 34b and the outer frame 35a, 35b) by the flanges 31a, 31b. It will be sealed.

In such a sealing structure 30, in order to ensure the sealing performance, the outer peripheral surface 38 of the plastically deformed metal gasket 32 is the inner surface of the outer frames 35a and 35b of the flanges 31a and 31b over the entire circumference. It is important to have even contact with. For this purpose, the flanges 31a and 31b and the metal gasket 32 are required to have a high degree of manufacturing accuracy. However, there is a limit to the current manufacturing method by press working or the like. In particular, in the case of a metal gasket having a shape other than a circular shape, the outward bulging length at the time of plastic deformation is not uniform. For this reason, it is extremely difficult to design and manufacture a seal structure having a metal gasket having a shape other than a circular shape so that even outward pressing is generated at the time of tightening.

Further, in the conventional seal structure 30 having a knife-edge type flange, as described above, the outer peripheral surface 38 of the metal gasket 32 becomes the inner surface of the outer frames 35a and 35b of the flanges 31a and 31b as the bolt is tightened. And the outward bulge of the metal gasket 32 is constrained. Therefore, there is an inconvenience that a very large force is required at the time of tightening.

Japanese Unexamined Patent Publication No. 6-174097 Japanese Unexamined Patent Publication No. 10-159979

The present invention has been made based on the above circumstances, and an object thereof is a seal structure that can be relatively easily designed into an arbitrary shape and has sufficient sealing performance, and this seal structure. Is to provide a sealing method using.

The present invention made to solve the above-mentioned problems includes a pair of flanges each having a seal portion and an annular metal gasket arranged between the seal portions of the pair of flanges, and the pair of flanges have the above-mentioned respective flanges. Each of the seal portions has a knife edge formed in an annular shape, the knife edges formed in each of the above seal portions have a similar shape in a plan view, and the difference in radius between these knife edges is more than 0 mm and 3 mm or less. , A seal structure in which the pair of surfaces of the metal gasket facing each of the seal portions are flat surfaces.

According to the seal structure, sufficient sealing performance can be exhibited. The reason for this is not clear, but the following can be inferred. In the seal structure, the knife edges provided on the pair of flanges are formed so as to have different sizes. Therefore, when the pair of flanges are pressed in the opposite direction with the metal gasket arranged between the seal portions of the pair of flanges, the two knife edges tend to bite into the metal gasket. Furthermore, it is presumed that shear deformation occurs in the metal gasket due to the biting of the upper and lower knife edges that are out of position. The seal structure has a structure capable of sealing between a pair of flanges and the metal gasket by such biting of the knife edge and shear deformation of the metal gasket, as in the conventional seal structure. , The pressing between the outer peripheral surface of the metal gasket and the outer frame of the flange is not always used. Therefore, according to the seal structure, sufficient sealing performance can be exhibited even when the pair of flanges are tightened with a relatively weak force. Further, since the seal structure does not necessarily utilize the pressing between the outer peripheral surface of the metal gasket and the outer frame of the flange, strict accuracy regarding the shape and size of the outer peripheral surface of the metal gasket and the inner surface of the outer frame of the flange. Is not required. Therefore, the seal structure can be relatively easily designed into any shape.

Further, in the seal structure, since the positions of the pair of knife edges are displaced from each other, even if the metal gasket once used is turned inside out and used, the knife edges will bite into a place different from the first biting point. .. Therefore, according to the seal structure, even if the metal gasket once used is turned inside out and used, sufficient sealing property can be exhibited, and the metal gasket can be used twice.

The term "annular" refers to a shape having a hole portion in a plan view, and is not limited to a circular shape. That is, if the "annular" is a shape having a hole portion in a plan view, the outer edge shape may be, for example, an ellipse, a square, or the like. Further, the outer edge shape and the inner edge shape may be different. For example, the outer edge may be square and a circular hole may be formed, that is, the inner edge may be circular.

Further, the "radius of the knife edge" means the distance from the center in a plan view. That is, when one (smaller) knife edge is arranged in the other (larger) knife edge so that the centers of the two are aligned with each other in a plan view, the separation distance between the two is more than 0 mm and 3 mm or less. If the difference in radius (distance) is not constant, the difference in minimum radius (distance) may be more than 0 mm and 3 mm or less, but the difference in minimum radius (distance) and the difference in maximum radius (distance). The distance) is preferably in the range of more than 0 mm and 3 mm or less.

The thickness of the metal gasket is preferably 2 mm or more and 5 mm or less. In the seal structure, by making the thickness of the metal gasket relatively large in this way, the knife edge can sufficiently bite into the metal gasket, and the metal gasket is sufficiently sheared and deformed due to the biting of the knife edge. The sealing performance can be further improved by making it easier to carry out.

The angle of the tip of the knife edge is preferably 40 ° or more and 80 ° or less. By setting the angle of the tip of the knife edge within the above range, the knife edge can sufficiently bite into the metal gasket, and the metal gasket is sufficiently easily sheared and deformed due to the biting of the knife edge. Can be further enhanced.

The seal structure is preferably used in a vacuum vapor deposition apparatus. The seal structure has sufficient sealing performance to be compatible with the seal structure of the vacuum vapor deposition apparatus.

Another invention made to solve the above problems is a sealing method using the sealing structure, in which the metal gasket is arranged between the sealing portions of the pair of flanges, and the pair of flanges. It is a sealing method including a step of biting the knife edge formed in each of the sealing portions into the metal gasket by pressing.

According to the sealing method, it is possible to perform sufficient sealing with a relatively weak force, so that workability can be improved. Further, since the seal structure used in the sealing method can be relatively easily designed into an arbitrary shape, the sealing method enables sealing of various shapes.

According to the present invention, it is possible to provide a seal structure that can be relatively easily designed into an arbitrary shape and has sufficient sealing performance, and a sealing method using this sealing structure.

FIG. 1 is a schematic partial cross-sectional view showing a seal structure according to an embodiment of the present invention. FIG. 2 is a schematic plan view showing the positional relationship between the knife edge and the metal gasket of the seal structure of FIG. 1. FIG. 3 is a schematic partial cross-sectional view showing a sealing method using the sealing structure of FIG. FIG. 4 is a schematic partial cross-sectional view showing a seal structure according to an embodiment different from that of FIG. FIG. 5 is a schematic partial cross-sectional view showing a conventional seal structure.

Hereinafter, the sealing structure and the sealing method according to the embodiment of the present invention will be described in detail with reference to the drawings as appropriate.

<Seal structure 10>
The seal structure 10 of FIG. 1 includes a pair of flanges 11a, 11b and a metal gasket 12.

(Flange)
The flange 11a is a tubular body. On the other hand, the flange 11b is a bottomed lid. The flange 11a has a sealing portion 13a. Further, the flange 11b has a sealing portion 13b. The sealed portion is a portion that forms a sealed state. The seal portion 13a is an upper portion of the flange 11a in FIG. 1, and includes a portion on which the metal gasket 12 is placed. The seal portion 13b is a lower portion of the flange 11b in FIG. The metal gasket 12 is arranged between the sealing portions 13a and 13b of the pair of flanges 11a and 11b.

A knife edge 14a is formed in an annular shape on the sealing portion 13a of the flange 11a. Further, a knife edge 14b is formed in an annular shape on the sealing portion 13b of the flange 11b. A knife edge is a linear protrusion with a knife-pointed tip. These linear protrusions form a ring in a plan view.

As shown in FIG. 2, the knife edge 14a and the knife edge 14b are both annular in a plan view, and specifically have a substantially rectangular shape (a rectangular shape in which each apex is rounded). The knife edge 14a and the knife edge 14b are similar figures having the same center in a plan view. In FIG. 2, the knife edges 14a and 14b show the tips (ridges) thereof.

In plan view, the knife edge 14a is provided on the outside of the knife edge 14b. Specifically, the difference A between the radius of the knife edge 14a and the radius of the knife edge 14b is more than 0 mm and 3 mm or less. That is, when the pair of flanges 11a and 11b are opposed to each other, the knife edge 14a is formed so as to be at an outer position separated from the knife edge 14b by more than 0 mm and 3 mm or less in the facing direction view (plan view shown in FIG. 2). ing. The radius of the knife edge is based on the position of the tip (ridge line) of the knife edge. According to the seal structure 10, the positions of the pair of knife edges 14a and 14b are displaced in this way, so that the two knife edges 14a and 14b bite into the metal gasket 12 and the metal gasket 12 is subjected to shear deformation. Since it can occur, sufficient sealing performance is exhibited even with a relatively weak force (see FIG. 3 described later).

The lower limit of the difference A between the radius of the knife edge 14a and the radius of the knife edge 14b is preferably 0.1 mm, more preferably 0.3 mm, still more preferably 0.5 mm, still more preferably 1 mm. Further, the upper limit of the difference A is preferably 2 mm, more preferably 1.5 mm, and even more preferably 1 mm.

The lower limit of the angle θ at the tips of the knife edges 14a and 14b is preferably 40 °, more preferably 50 °. When the angle θ of the tips of the knife edges 14a and 14b is equal to or higher than the above lower limit, the tips of the knife edges 14a and 14b are less likely to be chipped, and the metal gasket 12 can be effectively sheared and deformed when pressed. can. On the other hand, the upper limit of the angle θ is preferably 80 °, more preferably 70 °. When this angle θ is not more than the above upper limit, the knife edges 14a and 14b can effectively bite into the metal gasket 12 at the time of pressing. The angle of the tips of the knife edges 14a and 14b means the angle in the cross section perpendicular to the ridgeline of the knife edges 14a and 14b. The shapes of the knife edges 14a and 14b in this cross section may be an isosceles triangle shape or another triangular shape. Further, the tips of the knife edges 14a and 14b may be rounded.

The height B of the knife edges 14a and 14b is not particularly limited, but the lower limit is preferably 0.5 mm, more preferably 0.8 mm. By setting the height B of the knife edges 14a and 14b to be equal to or higher than the above lower limit, more sufficient biting and shear deformation can be caused at the time of pressing. On the other hand, the upper limit of the height B is preferably 3 mm, more preferably 1.5 mm. By setting the height B of the knife edges 14a and 14b to be equal to or less than the above upper limit, it is possible to suppress chipping of the knife edges 14a and 14b and improve the sealing performance.

Outer frames 15a and 15b are provided on the outer edges of the sealing portions 13a and 13b of the flanges 11a and 11b, respectively. Further, the outer frames 15a and 15b are provided with holes (not shown) for bolts 16 for tightening the flanges 11a and 11b.

The material of the flanges 11a and 11b is not particularly limited and is usually metal. Examples of the material of the flanges 11a and 11b include stainless steel and titanium, and stainless steel is preferable because it has good hardness and the like.

(Metal gasket)
The metal gasket 12 is a plate-like body having an annular shape in a plan view. Specifically, as shown in FIG. 2, the metal gasket 12 has an annular shape in which the outer edge and the inner edge are substantially rectangular (rectangular with rounded vertices) in a plan view. Further, in a plan view, the inner edge of the metal gasket 12 is smaller than the knife edge 14b, and the outer edge of the metal gasket 12 is larger than the knife edge 14a. That is, as shown in FIG. 2, in a plan view, the two knife edges 14a and 14b have a magnitude relationship of being covered with the metal gasket 12.

In the metal gasket 12, the pair of surfaces 17a and 17b (the upper surface and the lower surface of the metal gasket 12 in FIG. 1) facing the sealing portions 13a and 13b of the pair of flanges 11a and 11b are flat surfaces, respectively. That is, the metal gasket 12 is a flat plate. At the time of sealing, the knife edges 14a and 14b are bitten into the pair of surfaces 17a and 17b, respectively.

The lower limit of the thickness C of the metal gasket 12 is preferably 2 mm, more preferably 2.5 mm. By setting the thickness C of the metal gasket 12 to the above lower limit or more, the knife edges 14a and 14b can be sufficiently bitten and the sealing performance can be improved. On the other hand, as the upper limit of the thickness C, 5 mm is preferable, and 4 mm is more preferable. By setting the thickness C to the upper limit or less, the sealing performance can be improved by effectively causing shear deformation.

The lower limit of the width D of the ring portion of the metal gasket 12 is preferably 3 mm. 4 mm is more preferable. On the other hand, the upper limit of the width D is preferably 8 mm, more preferably 6 mm. By setting this width D of the metal gasket 12 within the above range, biting of the knife edges 14a and 14b and shear deformation of the metal gasket 12 are more likely to occur, and the sealing performance can be improved.

When the metal gasket 12 is arranged between the sealing portions 13a and 13b of the pair of flanges 11a and 11b, the outer peripheral surface 18 of the metal gasket 12 is in contact with the inner peripheral surface 19 of the outer frames 15a and 15b of the flanges 11a and 11b. It may or may not be in contact. For example, the lower limit of the maximum distance E between the outer peripheral surface 18 of the metal gasket 12 and the inner peripheral surface 19 of the outer frames 15a and 15b of the flanges 11a and 11b is preferably 0.1 mm, more preferably 0.3 mm. When the maximum distance E is equal to or greater than the above lower limit, the outer peripheral surface 18 of the metal gasket 12 bulges when the metal gasket 12 is pressed by the pair of flanges 11a and 11b, so that the inner peripheral surfaces of the outer frames 15a and 15b Since the force for pressing the 19 is not too large, the tightening can be performed with a weaker force. On the other hand, as the upper limit of the maximum distance E, 5 mm is preferable, and 3 mm is more preferable. When the maximum distance E is equal to or less than the above upper limit, the metal gasket 25 can be accurately and easily arranged between the sealing portions 13a and 13b of the pair of flanges 11a and 11b.

The material of the metal gasket 12 is not particularly limited, and various metals can be used, but copper and copper alloys are preferable, and oxygen-free copper is more preferable. These exhibit good performance, especially when used in vacuum. Examples of the oxygen-free copper include oxygen-free copper specified in JIS-C1020 and the like.

<Seal structure 20>
The seal structure 20 of FIG. 4 includes a pair of flanges 21a, 21b and a metal gasket 22. The seal structure 20 is substantially the same as the seal structure 10 of FIG. 1 except that both of the pair of flanges 21a and 21b are cylindrical. That is, the pair of flanges 21a and 21b each have a sealing portion 23a and 23b. Further, a knife edge 24a is formed in an annular shape on the sealing portion 23a of the flange 21a. A knife edge 24b is formed in an annular shape on the sealing portion 23b of the flange 21b. The seal structure 20 may be the same as the seal structure 10 of FIG. 1, except that one of the flanges 21b is cylindrical. The seal structure 20 is suitably used as a connecting member for piping.

<Use, etc.>
The seal structures 10 and 20 can be used as a seal structure for a vacuum device or another seal structure. The seal structures 10 and 20 enable sufficient vacuum sealing even in a high temperature environment exceeding 400 ° C., for example. Above all, the seal structures 10 and 20 are preferably used as the seal structure of the vacuum vapor deposition apparatus.

Examples of the vacuum vapor deposition apparatus include a vapor deposition material accommodating portion, a valve, and a vapor deposition material discharging portion, and having a structure in which the vapor deposition material accommodating portion and the valve, and the valve and the vapor deposition material discharging portion are connected by piping, respectively. .. The seal structure 10 of FIG. 1 can be used for a lid portion of such a vacuum vapor deposition apparatus, and the seal structure 20 of FIG. 4 can be used for a connecting portion of such a vacuum vapor deposition apparatus. Since the vacuum vapor deposition apparatus having the seal structure is sufficiently sealed by the seal structure, good vapor deposition performance can be exhibited. In the vacuum vapor deposition apparatus having the seal structure, two knife edges are usually bitten into both sides of the metal gasket, and the metal gasket is sheared and deformed by the two knife edges. However, the metal gasket does not have to be sheared and deformed.

<Seal method>
In the sealing method using the sealing structure 10, the pair of flanges 11a and 11b are pressed with the metal gasket 12 arranged between the sealing portions 13a and 13b of the pair of flanges 11a and 11b (see FIG. 1). A step of biting the two knife edges 14a and 14b into the metal gasket 12 is provided (see FIG. 3).

The pair of flanges 11a and 11b can be pressed by tightening the bolt 16. That is, when the pair of flanges 11a and 11b are pressed in the vertical direction in FIG. 1, the two knife edges 14a and 14b bite into the surfaces 17a and 17b of the metal gasket 12, respectively, and the two knife edges 14a and 14b are further formed. As a result, shear deformation of the metal gasket 12 may occur. According to the sealing method, such an action enables sufficient sealing with a relatively weak force.

In the sealing method, softening vacuum annealing treatment may be performed depending on the intended use. Further, the sealing method using the seal structure 20 is the same as the sealing method using the seal structure 10.

<Other embodiments>
The present invention is not limited to the above-described embodiment, and the configuration may be changed without changing the gist of the present invention. For example, in the seal structure 10 of FIG. 1, the diameter of the knife edge 14b of the flange 11b on the lid side is made smaller than the diameter of the knife edge 14a of the other flange 11a, but the opposite may be true. .. Further, the structure may be such that the pair of flanges are pressed by a method other than the bolt.

The sealing structure and sealing method of the present invention can be suitably used as parts of a vacuum device such as a vacuum vapor deposition apparatus and a sealing method.

10, 20, 30 Seal structure 11a, 11b, 21a, 21b, 31a, 31b Flange 12, 22, 32 Metal gasket 13a, 13b, 23a, 23b, 33a, 33b Seal part 14a, 14b, 24a, 24b, 34a, 34b Knife edge 15a, 15b, 35a, 35b Outer frame 16 Bolt 17a, 17b Surface 18, 38 Outer surface 19 Inner peripheral surface

Claims (5)

It is provided with a pair of flanges each having a sealing portion and an annular metal gasket arranged between the sealing portions of the pair of flanges.
The pair of flanges each have a knife edge formed in an annular shape on each of the sealing portions.
The knife edges formed on each of the above sealing portions are similar in plan view, and the difference in radius between these knife edges is 0.3 mm or more and 3 mm or less.
A seal structure in which a pair of surfaces of the metal gasket facing each of the seal portions are flat surfaces.
The seal structure according to claim 1, wherein the thickness of the metal gasket is 2 mm or more and 5 mm or less. The seal structure according to claim 1 or 2, wherein the angle of the tip of the knife edge is 40 ° or more and 80 ° or less. The seal structure according to claim 1, claim 2 or claim 3, which is used in a vacuum vapor deposition apparatus. A sealing method using the sealing structure according to any one of claims 1 to 4.
A sealing method comprising a step of biting the knife edge formed in each of the sealing portions into the metal gasket by pressing the pair of flanges in a state where the metal gasket is arranged between the sealing portions of the pair of flanges. ..

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