WO2011145481A1 - Beam welding method, vacuum packaging method, and vacuum heat-insulation material produced by vacuum packaging method - Google Patents

Abstract

The disclosed beam welding method involves: a metal-foil layering step of mounting a first metal foil and a second metal foil placed on the first metal foil on both a primary mounting surface and a secondary mounting surface of a support mount which are located adjacent to one another; a tight contact step of bringing the portions of the first and second metal foils mounted on the primary mounting surface into tight contact with one another along an imaginary welding line, with the portions of the first and second metal foils mounted on the secondary mounting surface being kept in a free state; and a welding-and-cutting step of cutting off the portions of the first and second metal foils mounted on the secondary mounting surface while welding together the portions of the first and second metal foils mounted on the primary mounting surface along the imaginary welding line by heating the first and second metal foils through convergent irradiation with an electron beam in a predetermined vacuum environment after the tight contact step.

Description

Beam welding method, vacuum packaging method, and vacuum heat insulating material produced by the vacuum packaging method

The present invention relates to a beam welding method in which a plurality of metal foils are welded to each other by beam irradiation, a vacuum packaging method in which inclusions are vacuum packaged, and a vacuum heat insulating material manufactured by the vacuum packaging method.

Conventionally, a plurality of thin plates are stacked while being pressed to form a laminate, and the laminate is irradiated with an electron beam in the direction in which the thin plates overlap, so that each thin plate is fused and welded at the melting cross section of each thin plate. A processing method using an electron beam welding machine that simultaneously melts and welds each thin plate has been proposed (see, for example, Patent Document 1).

Conventionally, the welded parts of a plurality of steel plates are overlapped with each other and pressed and restrained by a jig, and a high energy beam (laser beam or electron beam) is applied to the welded parts in a substantially perpendicular direction. A welding method using a high energy beam is also proposed, in which a weld joint is formed by irradiating and welding, and then welding is performed by irradiating the welded joint surface with a high energy beam from a substantially horizontal direction. (For example, refer to Patent Document 2).

Furthermore, conventionally, in a state where heat-resistant inclusions are inserted between a pair of metal plates, the plates are welded together over the entire circumference of each plate, and then in the space surrounded by the plates. A manufacturing method of a vacuum heat insulating material for vacuum-treating is also proposed. In this conventional method for manufacturing a vacuum heat insulating material, after evacuating from a through hole provided in one plate body, the through hole is sealed with a lid so that the space in the space surrounded by each plate body is reduced. Vacuum processing is performed. Conventionally, each plate has been formed in advance so that a central region of the plate is depressed so that a space is formed inside the plate in a state where the plates are overlapped with each other. Thereby, even if it is in the state where heat-resistant inclusions are arranged in the space surrounded by each plate body, the peripheral portions of the plate bodies are easily in contact with each other without any gap, and the welded joint between the peripheral portions of the plate bodies is more facilitated. This can be performed reliably (see, for example, Patent Document 3).

JP-A-49-83634 JP 59-47083 A JP 2006-17165 A

However, in the processing method using an electron beam welder disclosed in Patent Document 1, it is considered that when a thin plate is melted, each thin plate is pressurized so as not to move on both sides of the melted portion. Therefore, the thin plate is bent due to thermal distortion or the like at the melted portion of the thin plate, and there is a possibility that stable welding between the thin plates may not be performed.

Moreover, in the welding method by the high energy beam shown by patent document 2, after cutting a steel plate by irradiation of a high energy beam and forming a welded joint, it is substantially horizontal with respect to the mating surface of a welded joint. Irradiation with a high-energy beam increases the number of welding processes and deteriorates productivity. Furthermore, when the steel sheet is thin, it is difficult to irradiate a high energy beam so as to match the mating surface of the welded joint, and the welded joint is bent due to thermal distortion during welding, resulting in welding. Cannot be performed stably.

Furthermore, in the method for manufacturing a vacuum heat insulating material disclosed in Patent Document 3, after welding the entire circumference of each plate, vacuum processing is performed in a space surrounded by each plate, so that the plates are welded together. And vacuum processing in the space surrounded by the plates need to be performed independently. In addition, it is necessary to form each plate into a predetermined shape before performing welding between the plates or vacuum treatment. Therefore, the number of processes increases, and the productivity of the vacuum heat insulating material decreases. In addition, when drawing is performed when each plate is formed, when the thickness of each plate is thin, the plate is likely to break at the drawn portion, and the productivity of the vacuum heat insulating material further decreases. .

The present invention has been made to solve the above-described problems, and is manufactured by a beam welding method, a vacuum packaging method, and a vacuum packaging method capable of welding metal foils more reliably and easily. An object is to obtain a vacuum insulation material.

In the beam welding method according to the present invention, the first metal foil and the second metal foil stacked on the first metal foil are placed on each of the adjacent main mounting surface and the secondary mounting surface of the support base. When the support base is viewed along the direction in which the first and second metal foils overlap, the assumed welding line set between the main mounting surface and the secondary mounting surface is the first and second metal foils. The metal foil laminating step for arranging the first and second metal foils so as to cross the plane of the metal plate, and placing the first and second metal foil portions placed on the follower surface on the main placing surface The first and second metal foils are brought into close contact with each other along the assumed welding line, and the first and second metal foils are intensively irradiated with a beam under a predetermined vacuum environment after the close contact process. The first and second metal foil portions placed on the main placing surface are welded to each other by heating While welding along, and a welding fusing step to separate the portions of the first and second metal foil placed on the 従載 allowed surface.

The vacuum packaging method according to the present invention includes an insertion step of inserting inclusions between the first and second metal foils, and after the insertion step, the inclusions are viewed along the direction in which the first and second metal foils face each other. An adhesion process in which an assumed welding line is set around the inclusions at the time, and the first and second metal foils are in close contact with each other in a predetermined vacuum environment at a position closer to the inclusions than the assumed welding line, and adhesion After the process, the first and second metal foils are heated along the assumed welding line by concentrated irradiation of the beam in a predetermined vacuum environment. While welding the second metal foils along the welding assumption line, a welding fusing step is provided for cutting off the first and second metal foil portions in the surplus area farther from the inclusion than the welding assumption line. .

In the beam welding method according to the present invention, the first metal foil and the second metal foil stacked on the first metal foil are placed on the main placing surface and the subsidiary placing surface, respectively, and then placed on the subsidiary placing surface. In a state where the first and second metal foil portions placed are released, the first and second metal foil portions placed on the main placement surface are brought into close contact with each other along the assumed welding line. By heating the first and second metal foils by concentrated irradiation, the portions of the first and second metal foils placed on the main placing surface are welded to each other along the assumed welding line. Since the part of the 1st and 2nd metal foil mounted is cut | disconnected, the welding and fusing of the 1st and 2nd metal foil can be performed simultaneously. Thereby, the number of processes at the time of welding can be reduced, and welding of the first and second metal foils can be facilitated. In addition, since the first and second metal foils are welded and melted while supporting the first and second metal foils on the main mounting surface and the supporting surface on both sides of the assumed welding line, they are mounted on the supporting surface. The portions of the first and second metal foils can be detached while absorbing thermal strain by fusing, and the close contact state between the portions of the first and second metal foils placed on the main mounting surface It can be ensured more reliably. Thereby, joining by the welding of the part of the 1st and 2nd metal foil mounted on the main mounting surface can be made more reliable.

In the vacuum packaging method according to the present invention, the first and second metal foils are heated along the assumed welding line by concentrated irradiation of a beam in a predetermined vacuum environment, thereby covering the inclusion side more than the assumed welding line. Since the first and second metal foils in the region are welded to each other along the assumed welding line, the first and second metal foil portions in the surplus region farther from the inclusion than the assumed welding line are separated. The welding of the first and second metal foils and the vacuum treatment of the space surrounded by the first and second metal foils can be performed simultaneously. In addition, even if the first and second metal foils are not completely in close contact with each other, the first and second metal foils can be more reliably welded. The work of pre-forming by drawing can be eliminated. Therefore, it is possible to reduce the number of steps for manufacturing the vacuum package, and it is also possible to eliminate the possibility that the first and second metal foils are cracked by drawing. Thereby, the productivity of a vacuum package can be improved.

It is a typical top view which shows the installation state of metal foil when implementing the beam welding method by Embodiment 1 of this invention. It is sectional drawing along the II-II line of FIG. It is sectional drawing which shows the vacuum heat insulating material manufactured using the beam welding method by Embodiment 1 of this invention. It is sectional drawing which shows the installation state of metal foil when the beam welding method by the comparative example 1 is implemented. It is sectional drawing which shows the installation state of metal foil when the beam welding method by the comparative example 2 is implemented. It is sectional drawing which shows the vacuum packaging body manufactured by the vacuum packaging method by Embodiment 4 of this invention. It is a top view which shows the installation state at the time of the vacuum packaging process for manufacturing the vacuum packaging body of FIG. It is sectional drawing along the VIII-VIII line of FIG. It is a top view which shows the installation state at the time of the vacuum packaging process by Embodiment 5 of this invention. FIG. 10 is a cross-sectional view taken along line XX in FIG. 9. It is sectional drawing which shows the vacuum packaging body by Embodiment 6 of this invention.

Embodiment 1 FIG.
FIG. 1 is a schematic top view showing an installation state of a metal foil when performing a beam welding method according to Embodiment 1 of the present invention. 2 is a cross-sectional view taken along line II-II in FIG. In the figure, the first metal foil 1 and the second metal foil 2 are welded by a metal foil welding apparatus. The metal foil welding apparatus includes a vacuum chamber (not shown), a support base 3 installed in the vacuum chamber, and a pressing member for bringing the first metal foil 1 and the second metal foil 2 into close contact with each other on the support base 3. It has the apparatus 4, and the beam generator (heating apparatus) 5 (FIG. 2) which melts | melts, welding the 1st metal foil 1 and the 2nd metal foil 2 each other.

The support table 3 is installed in the vacuum chamber by being attached to a moving table (not shown) in the vacuum chamber. Further, the support base 3 can be moved horizontally in a predetermined direction with respect to the vacuum chamber. A beam groove 6 is provided on the upper surface of the support table 3 along the moving direction of the support table 3. As a result, the main mounting surface 7 and the secondary mounting surface 8 that are adjacent to each other via the beam groove 6 are formed on the upper surface of the support base 3. A part of the first metal foil 1 and the second metal foil 2 is placed on the main mounting surface 7 and the other part of the first metal foil 1 and the second metal foil 2 are mounted on the secondary mounting surface 8. Thereby, the 1st metal foil 1 and the 2nd metal foil 2 are arrange | positioned in the position which covers the beam groove 6 in the state piled up mutually.

The pressing device 4 has a pressing member 9 that can move together with the support 3 with respect to the vacuum chamber. The pressing member 9 is disposed in the region of the main mounting surface 7 when the support base 3 is viewed along the direction in which the first and second metal foils 1 and 2 overlap. The pressing member 9 is disposed along the longitudinal direction of the beam groove 6. The pressing device 4 presses the pressing member 9 against the main mounting surface 7 with the first and second metal foils 1 and 2 sandwiched between the pressing member 9 and the main mounting surface 7. The first and second metal foils 1 and 2 are in close contact with each other at the portion receiving the pressing force from the pressing member 9. When the first and second metal foils 1 and 2 are receiving a pressing force by the pressing device 4, the portions of the first and second metal foils 1 and 2 placed on the follower surface 8 are released. The portions of the first and second metal foils 1 and 2 placed on the main placing surface 7 are in close contact with each other along the longitudinal direction of the beam groove 6.

The beam generator 5 is fixed with respect to the vacuum chamber. Further, as shown in FIG. 2, the beam generator 5 irradiates the electron beam intensively from the upper side to the lower side of the support base 3. Therefore, the electron beam from the beam generator 5 is concentratedly irradiated on the second metal foil 2 that is superposed on the upper side of the first and second metal foils 1 and 2. The portion where the second metal foil 2 is irradiated with the electron beam is the irradiated portion 10 of the electron beam.

The optical axis of the electron beam emitted from the beam generator 5 intersects the beam groove 6. The support 3 and the holding member 9 are moved in the longitudinal direction of the beam groove 6 while maintaining the state where the optical axis of the electron beam and the beam groove 6 intersect each other.

The first and second metal foils 1 and 2 are melted while being welded to each other by being irradiated with the electron beam and heated by the irradiated portion 10. The irradiated portion 10 is moved in the longitudinal direction of the beam groove 6 with respect to the first and second metal foils 1 and 2 by the movement of the support base 3. The path along which the irradiated portion 10 is moved relative to the first and second metal foils 1 and 2 coincides with the assumed welding line 11 that is a reference line for welding. Accordingly, a portion (metal foil welded portion) 12 where the first and second metal foils 1 and 2 are welded to each other by irradiation with an electron beam is formed along the assumed welding line 11. As shown in FIG. 1, the assumed welding line 11 is set within the width of the beam groove 6 when the first and second metal foils 1 and 2 are viewed from above the support 3.

Next, a beam welding method for welding the first and second metal foils 1 and 2 will be described. First, the first metal foil 1 is placed on the upper surface of the support base 3. At this time, a part of the first metal foil 1 is placed on the main mounting surface 7 and the other part of the first metal foil 1 is placed on the follower surface 8. Thereafter, the second metal foil 2 is overlaid on the first metal foil 1. That is, the first metal foil 1 and the second metal foil 2 overlaid on the first metal foil 1 are placed on the main mounting surface 7 and the secondary mounting surface 8, respectively.

At this time, when the support table 3 is viewed from above (that is, when the support table 3 is viewed along the direction in which the first and second metal foils 1 and 2 overlap), the beam groove 6 and the assumed welding line. The first and second metal foils 1 and 2 are arranged so that 11 crosses the plane (range) of the first and second metal foils 1 and 2. Thereby, the 1st and 2nd metal foils 1 and 2 are the effective area | region (covering area | region) by the side of the main mounting surface 7 from the welding assumption line 11, and the surplus area | region by the side of the follower surface 8 from the welding assumption line 11. (Metal foil lamination process).

Thereafter, only the portions of the first and second metal foils 1 and 2 mounted on the main mounting surface 7 of the main mounting surface 7 and the secondary mounting surface 8 are pressed by the pressing member 9. That is, the pressing member 9 is pressed against the main mounting surface 7 with the first and second metal foils 1 and 2 sandwiched between the pressing member 9 and the main mounting surface 7. Thereby, the portions of the first and second metal foils 1 and 2 placed on the main placing surface 7 are brought into close contact with each other along the assumed welding line 11. At this time, the first and second metal foils 1 and 2 placed on the follower surface 8 are not pressed by the pressing member. Accordingly, the first and second metal foils 1 and 2 placed on the follower surface 8 are in a released state (contact process).

Thereafter, after the support base 3 to which the first metal foil 1, the second metal foil 2, and the pressing member 9 are attached is installed in the vacuum chamber, the vacuum chamber is sealed. Thereafter, the vacuum chamber is depressurized, and the environment in the vacuum chamber is changed to a predetermined vacuum environment of about 5 Pa.

Thereafter, the support 3 is moved along with the first metal foil 1, the second metal foil 2, and the pressing member 9 along the longitudinal direction of the beam groove 6 while irradiating the electron beam from the beam generator 5. Thereby, the irradiated part 10 moves on the welding assumption line 11, and the 1st and 2nd metal foils 1 and 2 are heated along the welding assumption line 11. FIG.

When the first and second metal foils 1 and 2 are heated along the welding assumption line 11, the first and second metal foils 1 and 2 are fused with the position of the welding assumption line 11 as a boundary. At this time, since the respective portions of the first and second metal foils 1 and 2 placed on the secondary placing surface 8 are released, the first portion placed on the main placing surface 7 while absorbing thermal strain. The first and second metal foils 1 and 2 are separated from the respective portions. At this time, the portions of the first and second metal foils 1 and 2 mounted on the main mounting surface 7 are in close contact with each other by the pressing member 9, so that they are melted together and welded along the assumed welding line 11. Is done. That is, when the first and second metal foils 1 and 2 are heated along the welding assumption line 11, the portions of the first and second metal foils 1 and 2 placed on the main mounting surface 7 are brought together. While being welded along the assumed welding line 11, the portions of the first and second metal foils 1 and 2 placed on the follower surface 8 absorb thermal distortion and are separated (welding fusing step).

Thereafter, the pressure in the vacuum chamber is returned to atmospheric pressure, whereby the welding of the first and second metal foils 1 and 2 is completed.

Next, a vacuum heat insulating material manufactured using the beam welding method according to Embodiment 1 of the present invention will be described. FIG. 3 is a sectional view showing a vacuum heat insulating material manufactured using the electron beam welding method according to Embodiment 1 of the present invention. In the figure, the vacuum heat insulating material 21 has a container 22 and a core member 23 accommodated in the container 22.

The container 22 has a first metal foil 1 and a second metal foil 2 facing each other. The peripheral portions of the first and second metal foils 1 and 2 are joined by welding in the beam welding method according to Embodiment 1 of the present invention. In other words, the metal foil welded portion 12 that joins the first and second metal foils 1 and 2 to each other is formed in the container 22 along the first and second peripheral portions. The space surrounded by the first and second metal foils 1 and 2 is sealed by joining the peripheral portions of the first and second metal foils 1 and 2 together. The space surrounded by the first and second metal foils 1 and 2 is in a predetermined vacuum state (for example, a vacuum state of about 5 Pa or less).

The core material 23 is inserted between the first metal foil 1 and the second metal foil 2. Moreover, the core material 23 has the fiber sheet 24 comprised by the laminated form. For example, a glass fiber sheet or the like is used as the fiber sheet 24.

The vacuum heat insulating material 21 is formed by inserting the core material 23 between the first metal foil 1 and the second metal foil 2 and then, in a predetermined vacuum environment, the first and second portions around the core material 23. It is obtained by welding the portions of the metal foils 1 and 2 using the beam welding method described above.

When the vacuum heat insulating material 21 is manufactured, the peripheral portions of the first and second metal foils 1 and 2 are partially joined together by welding, and a metal foil bag having a part opened is prepared in advance. You may keep it. For example, when the rectangular vacuum heat insulating material 21 is manufactured, only three sides of the four sides of the peripheral portions of the first and second metal foils 1 and 2 having a square shape are joined by welding using the beam welding method described above. A metal foil bag may be prepared.

In this case, the metal foil bag into which the core member 23 is inserted is installed in the vacuum chamber, and after the environment in the vacuum chamber is set to a predetermined vacuum environment (for example, a vacuum environment of about 5 Pa or less), the metal foil bag is opened. The first and second metal foils 1 and 2 at the mouth are brought into close contact with each other by pressing of the pressing member 9. Then, the vacuum heat insulating material 21 is manufactured by joining and closing the opening of the metal foil bag by the beam welding method described above.

Example 1.
While changing the thickness of each of the two metal foils (first and second metal foils 1 and 2) stacked on each other in the order of 30 [μm], 50 [μm] and 80 [μm], the above beam Attempts were made to weld metal foils by welding. In this example, the first and second metal foils 1 and 2 are made of the same metal (stainless steel (SUS304)). The first and second metal foils 1 and 2 were rectangular metal foils having a vertical dimension of 150 [mm] and a horizontal dimension of 100 [mm].

As a result, stable welding fusing was confirmed when the thickness of the stainless steel foil was 30 [μm], 50 [μm], and 80 [μm]. For example, when the thickness of the stainless steel foil is 50 [μm], stable welding fusing was confirmed when the output current of the electron beam was in the range of 4.5 [mA] to 6.0 [mA]. Further, if the thickness of the stainless steel foil is different, the output current of the electron beam when stable welding fusing is confirmed, and the feed speed when moving the irradiated portion 10 along the assumed welding line 11 may also be different. confirmed. Therefore, in consideration of the heat input to the metal foil, the setting condition at the time of the above-described welding fusing process was examined by the following relational expression (1).

A1 ≦ I / (t · v) ≦ a2 (1)

Here, I [A] is the output current of the electron beam, t [mm] is the average value of the thicknesses of the first and second metal foils 1 and 2, and v [m / min] is the irradiated portion 10. Is the feed rate when moving along the assumed welding line 11.

In this case, since the thermal conductivity, melting point, and the like differ depending on the material, it is considered that there is an appropriate proper heat input amount for each material when stable welding fusing is realized. Therefore, it is considered that the values of a1 and a2 in the relational expression (1) are determined in accordance with the types of metals constituting the first and second metal foils 1 and 2.

Therefore, by changing the type of metal constituting the first and second metal foils 1 and 2 and carrying out the welding test by the above beam welding method, a unique metal type lower limit P corresponding to the type of metal. In addition, the metal type upper limit value Q is individually specified, the metal type lower limit value P is a1 value, and the metal type upper limit value Q is a2 value, thereby specifying each value of a1 and a2.

In the welding test, stainless steel and iron-based metal, copper-based metal, aluminum-based metal, and titanium-based metal were used as materials constituting the first and second metal foils 1 and 2. In the welding test, the thicknesses of the first and second metal foils 1 and 2 were the same. As a result, it was found that the metal type lower limit P and the metal type upper limit Q are more clearly determined for each metal type. That is, P = 5 and Q = 15 when the metal types of the first and second metal foils 1 and 2 are stainless steel and iron-based, and P = 100 and Q = 175 when copper-based. In the case of aluminum, P = 5 and Q = 30, and in the case of titanium, P = 2.5 and Q = 45. From this result, it can be treated that stainless steel and iron-based metal are the same type of metal.

That is, when the materials of the first and second metal foils 1 and 2 are the same type of metal, the metal type lower limit P corresponding to the type of metal constituting the first and second metal foils 1 and 2 is used. And the metal type upper limit Q is the respective values of a1 and a2 in the above relational expression (1), and the above welding fusing process is performed under the conditions satisfying the relational expression (1) set as a1 = P and a2 = Q. Thus, it was found that stable welding fusing can be realized.

In the welding test, the distance between the pressing member 9 and the assumed welding line 11 when the support base 3 is viewed from above is set to about 5 [mm]. It was confirmed that when the distance between the pressing member 9 and the assumed welding line 11 exceeds 10 [mm], the metal foil is distorted by heat input from the electron beam and the welding stability is lowered. Further, in consideration of the placement likelihood at the time of mass production when installing the metal foil on the moving table, the distance between the edge of the first and second metal foils 1 and 2 and the assumed welding line 11 is about 5 mm. ].

As for the above metals, for example, stainless steel is stainless steel or nickel steel, copper is copper, brass and phosphor bronze, aluminum is aluminum or duralumin, titanium is titanium or titanium alloy, iron is general There are rolled structural steels and plain cast iron.

Next, a comparative example for comparison with the beam welding method according to the first embodiment will be described.

Comparative Example 1
In Comparative Example 1, the same stainless steel foil as in Example 1 having a thickness of 50 [μm] was used as the first and second metal foils 1 and 2. Further, in Comparative Example 1, not only the first and second metal foils 1 and 2 placed on the main placing surface 7 but also the first and second metal foils 1 placed on the slave placing surface 8. , 2 portions were also in contact with each other along the assumed welding line, and a welding fusing process was performed by electron beam irradiation.

That is, FIG. 4 is a cross-sectional view showing an installation state of the metal foil when the beam welding method according to Comparative Example 1 is performed. In the first comparative example, the configuration of the pressing device 101 for bringing the first and second metal foils 1 and 2 into close contact with each other is different from that of the pressing device 4 of the first embodiment. That is, the pressing device 101 includes a first pressing member 102 that makes the first and second metal foils 1 and 2 mounted on the main mounting surface 7 in close contact with each other, and a first pressing member 102 that is mounted on the secondary mounting surface 8. And a second pressing member 103 for bringing the portions of the second metal foils 1 and 2 into close contact with each other.

The first pressing member 102 and the second pressing member 103 are arranged in parallel to the longitudinal direction of the beam groove 6. Therefore, in the first comparative example, the portions of the first and second metal foils 1 and 2 mounted on the main mounting surface 7 are not only brought into close contact with each other along the assumed welding line, but are also mounted on the secondary mounting surface 8. The portions of the first and second metal foils 1 and 2 are also brought into close contact with each other along the assumed welding line. Other configurations are the same as those in the first embodiment.

In Comparative Example 1, the portions of the first and second metal foils 1 and 2 placed on the main placing surface 7 are brought into close contact with each other along the assumed welding line, and the first and second pieces placed on the follower surface 8 are adhered to each other. The welding fusing process was performed in a state in which the portions of the metal foils 1 and 2 of 2 were brought into close contact with each other along the assumed welding line. As a result, in Comparative Example 1, the welding and cutting process tried to join the first and second metal foils 1 and 2 while changing the conditions such as the feed rate of the electron beam and the irradiated part 10. The part became discontinuous, or the material melted too much and a hole was formed, so that stable welding fusing could not be realized.

Comparative Example 2
Also in Comparative Example 2, the same stainless steel foil as in Comparative Example 1 was used as the first and second metal foils 1 and 2. Moreover, in the comparative example 2, the part of the support base provided with the secondary mounting surface 8 is eliminated, and only the part of the support base provided with the main mounting surface 8 is left, and the first and second metal foils 1, 2 are provided. A part of this was placed on the main mounting surface 7 and the other part of the first and second metal foils 1 and 2 was not supported from below, and a welding fusing process by irradiation with an electron beam was performed.

That is, FIG. 5 is a cross-sectional view showing an installation state of the metal foil when the beam welding method according to Comparative Example 2 is performed. In Comparative Example 2, the configuration of the support base 104 is different from that of the support base 3 of the first embodiment. That is, only the main mounting surface 7 is provided on the upper surface of the support base 104. Therefore, a support base does not exist below the portions of the first and second metal foils 1 and 2 to be placed on the follower surface, and is a space. Other configurations are the same as those in the first embodiment.

In Comparative Example 2, the first and second metal foils 1 and 2 placed on the main placing surface 7 are brought into close contact with each other along the assumed welding line, and the first and second portions to be placed on the follower surface. The welding fusing process was performed with the metal foils 1 and 2 being unsupported. As a result, in the comparative example 2, in the welding fusing process, the first and second metal foils 1 and 2 are joined together while changing conditions such as the electron beam and the feed speed of the irradiated portion 10 and the position of the pressing member 9. However, even if the pressing member 9 was brought close to a distance of several mm close to the assumed welding line, stable welding fusing could not be realized.

In such a beam welding method, after placing the first metal foil 1 and the second metal foil 2 superimposed on the first metal foil 1 on each of the main placing surface 7 and the follower surface 8, The first and second metal foils 1 and 2 placed on the main placing surface 7 are in a state in which the first and second metal foils 1 and 2 placed on the sub-mounting surface 8 are released. Are brought into close contact with each other along the assumed welding line 11, and the first and second metal foils 1 placed on the main placing surface 7 are heated by heating the first and second metal foils 1 and 2 by concentrated beam irradiation. , 2 portions are welded along the assumed welding line 11, and the first and second metal foils 1 and 2 placed on the follower surface 8 are separated, so the first and second metal foils are separated. 1, 2 welding and fusing can be performed simultaneously. Thereby, the number of processes at the time of welding can be reduced, and welding of the first and second metal foils 1 and 2 can be facilitated. Further, while supporting the first and second metal foils 1 and 2 on the main mounting surface 7 and the secondary mounting surface 8 on both sides of the assumed welding line 11, welding and fusing of the first and second metal foils 1 and 2 are performed. Therefore, the first and second metal foils 1 and 2 mounted on the main mounting surface 7 are supported by supporting the surplus region portions of the first and second metal foils 1 and 2 on the secondary mounting surface 8. The close contact state between the parts can be ensured more reliably. Thereby, joining by the welding of the part of the 1st and 2nd metal foils 1 and 2 mounted on the main mounting surface 7 can be made more reliable.

Further, a beam groove 6 is provided between the main mounting surface 7 and the secondary mounting surface 8, and the assumed welding line 11 extends the support base 3 along the direction in which the first and second metal foils 1 and 2 overlap. Since it is located within the range of the width of the beam groove 6 when viewed, the space below the heated portion of the first and second metal foils 1 and 2 can be made a space. Thereby, even if the beam which melted | melted the 1st and 2nd metal foil 1 and 2 was irradiated to the support stand 3, and the support stand 3 was melted, the 1st and 2nd metal foil 1 and 2 and the support stand 3 Can be prevented from joining.

Further, since the beam intensively irradiated onto the first and second metal foils 1 and 2 is an electron beam, the beam for heating the first and second metal foils 1 and 2 can be easily and more reliably obtained. Can be irradiated.

In addition, since the thickness of each of the first and second metal foils 1 and 2 is at least one of 100 [μm] or less, it is more difficult to weld thin metal foils, which has been difficult in the past. It can be done reliably and easily. Thereby, the application to the joining of the electronic device which is not until now, the joining of the packaging material of a vacuum heat insulating material, etc. can be aimed at, and the use can be expanded.

In addition, the metal type lower limit P and the metal type upper limit Q are specified in correspondence with the types of metals constituting the first and second metal foils 1 and 2, and the first and second metal foils 1 and 2 are specified. 2 is a metal of the same type, the metal type lower limit P and the metal type upper limit Q corresponding to the type of metal constituting the first and second metal foils 1 and 2 are represented by the above relationship. Since it is set as the value of a1 and the value of a2 of Formula (1), a welding fusing process can be performed on the appropriate conditions according to the kind of metal which comprises the 1st and 2nd metal foils 1 and 2. Therefore, more stable welding fusing can be performed on the first and second metal foils 1 and 2.

Also, P = 5 and Q = 15 when the metal type is stainless steel and iron-based, P = 100 and Q = 175 when copper-based, and P = 5 and Q = 30 when aluminum-based. Since it is set as P = 2.5 and Q = 45 in the case of a titanium system, the types of metals constituting the first and second metal foils 1 and 2 are stainless steel and iron system, copper system, aluminum system and In the case of the titanium system, the welding conditions of the beam welding method can be clarified, and the welding fusing of the first and second metal foils 1 and 2 can be more reliably performed.

Further, in the vacuum heat insulating material 21 as described above, the container 22 is produced by welding the first and second metal foils 1 and 2 by the beam welding method according to the first embodiment of the present invention. The container 22 with few welding defects can be easily produced. Moreover, the thickness of the 1st and 2nd metal foils 1 and 2 in the container 22 can be made thin easily. For example, the container 22 can be produced using a metal foil of 50 [μm]. Thereby, the heat insulation performance of the vacuum heat insulating material 21 can be improved. That is, when the thickness of the metal foil in the container 22 is large, a phenomenon called a heat bridge in which heat moves around the outside of the core member 23 while traveling through the metal foil of the container 22 is likely to occur. By reducing the thickness of the first and second metal foils 1 and 2 in 22, the heat flow that is moved by the heat bridge can be suppressed, and the heat insulating performance of the vacuum heat insulating material 21 can be improved. Moreover, unlike the conventional vacuum heat insulating material by which the container is produced using the general laminate sheet which consists of a polymer film and aluminum foil or a vapor deposition film, the 1st and 2nd metal foils 1 and 2 are mutually Since the container 22 is produced by welding, a high heat resistance (for example, a heat resistance exceeding 300 ° C., for example) is obtained by using the core material 23 composed of a fiber having high heat resistance (for example, glass fiber or ceramic fiber). Can be obtained.

Embodiment 2. FIG.
In the first embodiment, the materials of the first and second metal foils 1 and 2 are the same type of metal. However, in the second embodiment, the first and second metal foils 1 and 2 are used. Each material is made of different metals. The configuration of the metal foil welding apparatus and the procedure of the beam welding method are the same as those in the first embodiment.

That is, even when the materials constituting the first and second metal foils 1 and 2 are dissimilar metals, by performing the welding test by the above beam welding method while changing the combination of the metal types, The welding conditions of the welding fusing process when stable welding fusing was realized were investigated. As the metal in the welding test, as in Example 1, stainless steel and iron-based metal, copper-based metal, aluminum-based metal, and titanium-based metal were used. In the welding test, the first and second metal foils 1 and 2 were irradiated with an electron beam, and the thicknesses of the first and second metal foils 1 and 2 were the same.

As a result, each of the metal type lower limit P corresponding to the type of metal constituting each of the first and second metal foils 1 and 2 and the average value of each metal type lower limit P is set to the above value. Set as the value of a1 in the relational expression (1), and each metal type upper limit Q corresponding to the type of metal constituting the first and second metal foils 1 and 2, and each metal type upper limit Q Any one of the average values is set as the value of a2 in the above relational expression (1), and the welding fusing process is performed under the condition satisfying the relational expression (1) in which each value of a1 and a2 is set. As a result, stable welding fusing was realized. The metal type lower limit value P and the metal type upper limit value Q are specific values specified according to the type of metal, so stainless steel and iron-based metal, copper-based metal, aluminum-based metal, and Each of the titanium-based metals has the same value as in Example 1.

As to which value of each metal type lower limit P and the average value of each metal type lower limit P is set as the value of a1, each of the metals constituting the first and second metal foils 1 and 2 is set. It depends on the combination of types. That is, when the difference between each metal type lower limit P corresponding to each metal type is small (for example, in the case of a combination of stainless steel foil and aluminum foil, etc.), the second metal that is directly irradiated with the electron beam. The metal type lower limit P corresponding to the type of metal constituting the foil 2 is set as the value of a1. When the difference between the metal type lower limit values P corresponding to the respective metal types is large (for example, in the case of a combination of a copper foil and an aluminum foil), the first and second metal foils 1 and 2 are used. The average value of each metal type lower limit P corresponding to each of the types of metals constituting the is set as the value of a1.

Which value of each metal type upper limit value Q and the average value of each metal type upper limit value Q is set as the value of a2 also depends on each of the metals constituting the first and second metal foils 1 and 2. It depends on the combination of types. That is, when the difference between each metal type upper limit Q corresponding to each metal type is small (for example, in the case of a combination of stainless steel foil and aluminum foil, etc.), the second metal that is directly irradiated with the electron beam. The metal type upper limit Q corresponding to the type of metal constituting the foil 2 is set as the value of a1. Further, when the difference between the metal type upper limit values Q corresponding to the respective metal types is large, the respective metal type upper limit values respectively corresponding to the metal types constituting the first and second metal foils 1 and 2. The average value Q is set as the value of a2.

Thus, even if each material of the 1st and 2nd metal foils 1 and 2 is a different kind of metal, each value of a1 and a2 of the above-mentioned relational expression (1) is set appropriately. By doing, welding and fusing of 1st and 2nd metal foil 1 and 2 can be performed more reliably and easily. Therefore, for example, the present invention can be applied to a heat exchanger in which a copper-based metal and an aluminum-based metal are mixed, welding of a heat sink of an electronic device, and the like, and the application can be expanded.

Embodiment 3 FIG.
In the first embodiment, the irradiated portion 10 of the electron beam is moved along the assumed welding line 11 while keeping the irradiation amount of the electron beam constant in the welding fusing process, but in the third embodiment, the welding fusing is performed. In the process, the irradiated portion 10 of the electron beam is moved along the assumed welding line 11 while reducing the irradiation amount of the electron beam. The configuration of the metal foil welding apparatus and the procedure of the beam welding method are the same as those in the first embodiment.

That is, when the material of the first and second metal foils 1 and 2 is a metal having higher thermal conductivity than a metal such as stainless steel (for example, an aluminum-based or copper-based metal) and the welding distance is long. In this case, the temperature of the metal foil is different between when welding is started by irradiation with an electron beam and when welding progresses. Therefore, if the amount of heat input from the electron beam is constant, the welding state becomes unstable.

Here, welding was attempted using a pure copper foil having a thickness of 10 [μm] to a welding distance of 250 [mm]. When the output current value is set to 1.2 [mA] and welding is performed at an electron beam feed rate of 0.8 [m / min] while keeping the output current value constant, hamping becomes stronger as welding progresses. Welding has become unstable.

Therefore, in the beam welding method according to the third embodiment, the irradiated portion 10 is moved along the assumed welding line 11 while reducing the irradiation amount of the electron beam in the welding fusing process. Specifically, lamp output control was performed such that the output current value of the electron beam was 1.2 [mA] at the start of welding and 1.0 [mA] at the end of welding. As a result, stable welding fusing was realized from the start to the end of electron beam irradiation.

In such a beam welding method, in the welding fusing process, the irradiated portion 10 of the beam is moved along the assumed welding line 11 while reducing the irradiation amount of the beam. Therefore, even if the welding distance is long, The welding fusing between the first and second metal foils 1 and 2 can be more reliably and easily performed. Therefore, welding of copper foil, which has been difficult in the past, can be easily performed. As a result, the present invention can be applied to, for example, an electrode material of a lithium battery, and the use can be further expanded.

The thicknesses of the first and second metal foils 1 and 2 do not have to be the same, but the thickness of one of the first and second metal foils 1 and 2 is the other thickness. It is preferable to set it to 10 times or less. More preferably, the thickness of one is set to 3 times or less the thickness of the other. Moreover, the beam irradiated to the 1st and 2nd metal foils 1 and 2 is not restricted to an electron beam, For example, it is good also as a laser beam.

In each of the above embodiments, the number of metal foils is two, ie, the first and second metal foils 1 and 2, but the number of metal foils may be three or more.

Embodiment 4 FIG.
FIG. 6 is a cross-sectional view showing a vacuum package manufactured by the vacuum packaging method according to Embodiment 4 of the present invention. In the figure, the vacuum package 31 has a container 32 and inclusions 33 housed in the container 32. The container 32 includes a first outer cover material 34 and a second outer cover material 35 that face each other.

The first and second outer cover materials 34 and 35 are each made of a metal foil (metal plate) having a predetermined thickness. Moreover, each shape of the 1st and 2nd jacket materials 34 and 35 is made the same. In this example, the first and second outer cover materials 34 and 35 are formed of a rectangular stainless steel foil (SUS304) having a thickness of 80 μm.

The inclusion 33 is inserted between the first jacket material 34 and the second jacket material 35. The peripheral portions of the first and second jacket materials 34 and 35 are joined by welding. That is, a welded portion 36 for joining the first and second jacket materials 34 and 35 to each other is formed in the container 32 along the peripheral edge portions of the first and second jacket materials 34 and 35. . The space surrounded by the first and second jacket materials 34 and 35 is sealed by joining the peripheral portions of the first and second jacket materials 34 and 35 with the welded portion 36.

The space surrounded by the first and second jacket materials 34 and 35 is in a predetermined vacuum state (in this example, a vacuum state in the range of 0.1 Pa to 15 Pa). Thereby, the inclusion 33 arranged in the space surrounded by the first and second jacket materials 34 and 35 is difficult to touch the atmosphere. For example, when the inclusion 33 is an electronic component whose deterioration is accelerated by contact with the atmosphere, the inclusion 33 is sealed in the container 32 in a predetermined vacuum state, so that the deterioration of the inclusion 33 progresses. Is suppressed, and the inclusion 33 can be stored for a long time. Moreover, when the adsorbent used by physical adsorption, for example, a desiccant or an oxygen scavenger, is used as the inclusion 33, the performance can be maintained in an unadsorbed state, which is effective for long-term storage after production.

Next, vacuum packaging for manufacturing the vacuum packaging body 31 will be described. FIG. 7 is a top view showing an installation state at the time of vacuum packaging processing for manufacturing the vacuum packaging body 31 of FIG. 6. FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. The vacuum packaging apparatus includes a vacuum chamber (not shown), a support base 37 installed in the vacuum chamber, and the first metal foil 1 and the second metal foil 2 (FIG. 8) on the support base 37. A pressing device 38 that is partially adhered and a beam generating device (heating device) 39 (FIG. 3) that melts and melts the first metal foil 1 and the second metal foil 2 are provided.

The configuration of the support base 37 is the same as the configuration of the support base 3 of the first embodiment. That is, the support base 37 can move horizontally in a predetermined direction with respect to the vacuum chamber. As shown in FIG. 8, a beam groove 6 is provided on the upper surface of the support base 37 along the moving direction of the support base 37. As a result, the main mounting surface 7 and the secondary mounting surface 8 that are adjacent to each other via the beam groove 6 are formed on the upper surface of the support base 37. A part of the first metal foil 1 and the second metal foil 2 is placed on the main mounting surface 7 and the other part of the first metal foil 1 and the second metal foil 2 are mounted on the secondary mounting surface 8. Thereby, the 1st metal foil 1 and the 2nd metal foil 2 are arrange | positioned in the position which covers the beam groove 6 in the state piled up mutually.

The pressing device 38 includes an inner pressing member 40 that can move together with the support base 37 with respect to the vacuum chamber, and an outer pressing member 41 that does not move relative to the beam generator 39. The inner pressing member 40 and the outer pressing member 41 are pressed against the support base 37 via the first and second metal foils 1 and 2, respectively. The first and second metal foils 1 and 2 are brought into close contact with each other at the portion receiving the pressing force from each of the inner pressing member 40 and the outer pressing member 41.

The inner pressing member 40 and the outer pressing member 41 are arranged on both sides of the beam groove 6 in the width direction. Moreover, the inner side pressing member 40 and the outer side pressing member 41 are each arrange | positioned along the longitudinal direction of the beam groove 6, as shown in FIG.

The inner pressing member 40 moves so as not to change relative to the movement of the support base 37, while the outer pressing member 41 is moved in parallel to the longitudinal direction of the beam groove 6. Therefore, in front of the irradiation position of the electron beam, the inner pressing member 40 and the outer pressing member 41 are opposed to each other across the width direction of the beam groove 6, but on the rear side, that is, a welded portion from the irradiation position. Then, only the inner pressing member 40 exists, and there is no outer pressing member 41 at a position facing it.

The configuration of the beam generator 39 is the same as that of the beam generator 5 of the first embodiment. That is, as shown in FIG. 8, the beam generator 39 irradiates the electron beam intensively from the upper side to the lower side of the support base 37. The electron beam irradiation part in the beam generator 39 is fixed in the vacuum chamber. The optical axis of the electron beam emitted from the beam generator 39 intersects the beam groove 6. The support base 37 and the inner pressing member 40 move in the longitudinal direction of the beam groove 6 with respect to the electron beam optical axis and the outer pressing member 41 while maintaining the state where the optical axis of the electron beam and the beam groove 6 intersect. Is done.

Further, the beam generator 39 concentrates the electron beam on one of the first and second metal foils 1 and 2 stacked on the support base 37 and stacked on the upper side. As a result, the first and second metal foils 1 and 2 are heated at portions (irradiated portions) 42 where the optical axes of the electron beams intersect with the metal foils 1 and 2, respectively. The irradiated portion 42 is moved in the longitudinal direction of the beam groove 6 with respect to the first and second metal foils 1 and 2 by moving the support base 37 with respect to the optical axis of the electron beam. The first and second metal foils 1 and 2 are melted while being welded to each other at the irradiated portion 42 by being heated by being irradiated with the electron beam. Accordingly, the path along which the irradiated portion 42 moves with respect to the first and second metal foils 1 and 2 indicates the welding assumption line 43 that is a reference line for performing welding, and the support base 37 is moved from above. When viewed, it is positioned so as to be within the range inside the width of the beam groove 6.

Next, a vacuum packaging method for manufacturing the vacuum packaging body 31 will be described. When the vacuum package 31 is manufactured, the peripheral portions of the first and second metal foils 1 and 2 are partially joined together by welding, and a metal foil bag that is partially opened is prepared in advance. . In this example, each shape of the 1st and 2nd metal foils 1 and 2 is made into a rectangular shape, and only 3 sides among the 4 sides of the peripheral part of the 1st and 2nd metal foils 1 and 2 are made. Metal foil bags are made by welding.

After this, the inclusion 33 is inserted into the metal foil bag through the opening. Thereby, the inclusion 33 is inserted between the first metal foil 1 and the second metal foil 2, and a packaging intermediate in which the inclusion 33 is accommodated in the metal foil bag is completed (insertion step).

After this, the packaging intermediate (that is, the inclusion 33 inserted between the first and second metal foils 1 and 2) is placed on the support base 37. At this time, the packaging intermediate is laid and placed so that the first and second metal foils 1 and 2 face each other in the vertical direction. At this time, the packaging intermediate for the support base 37 is installed so that the beam groove 6 crosses between the opening of the metal foil bag and the inclusion 33 when the support base 37 is viewed from above. To do. As a result, the first metal foil 1 and the second metal foil 2 stacked on the first metal foil 1 are placed on the main mounting surface 7 and the secondary mounting surface 8, respectively. Thereby, the welding assumption line 43 with respect to a packaging intermediate body becomes a position between the opening of a metal foil bag and the inclusion 33, as shown in FIG. At this time, the packaging intermediate is such that the inclusion 33 exists in the region of the main mounting surface 7 when the support base 37 is viewed along the direction in which the first and second metal foils 1 and 2 overlap. Are arranged with respect to the support base 37. Thereby, the 1st and 2nd metal foils 1 and 2 are the effective area | region (covering area | region) of the inclusion 33 side rather than the welding assumption line 43, and the surplus area | region which was separated from the inclusion 33 rather than the welding assumption line 43. (Metal foil lamination process).

After this, the inside of the vacuum chamber is depressurized to bring the packaging intermediate to a predetermined vacuum pressure. In this example, the pressure was reduced to a range of 0.1 Pa to 15 Pa. Thereafter, the first and second metal foils 1 and 2 are held by the inner pressing member 40 at a position closer to the inclusion 33 than the assumed welding line 43 while maintaining the state where the packaging intermediate is disposed in a predetermined vacuum environment. The two metal foils 1 and 2 are brought into close contact with each other by the outer pressing member 41 at a position farther from the inclusion 33 than the assumed welding line 43. At this time, the outer pressing member 41 and the inner pressing member 40 are positioned to face each other in the longitudinal direction of the beam groove 6 (contact process).

Thereafter, the support 37 is moved together with the inner pressing member 40 along the longitudinal direction of the beam groove 6 while irradiating the electron beam from the irradiation unit of the beam generator 39. Thereby, the irradiated part 42 moves on the welding assumption line 43 and heats the first and second metal foils 1 and 2 along the welding assumption line 43.

At this time, the outer pressing member 41 is moved relative to the first and second metal foils 1 and 2 while maintaining the positional relationship with the irradiated portion 42. That is, the range in which the first and second metal foils 1 and 2 are in close contact with each other by the outer pressing member 41 changes according to the movement of the irradiated portion 42 with respect to the first and second metal foils 1 and 2. . Thus, the first and second metal foils 1 and 2 are brought into close contact with each other by the outer pressing member 41 only in a range corresponding to an unwelded portion where the first and second metal foils 1 and 2 are not welded. .

When the first and second metal foils 1 and 2 are heated along the welding assumption line 43, the first and second in the covering region (that is, the region on the inclusion 33 side from the welding assumption line 43). While the metal foils 1, 2 are welded along the assumed welding line 43, the first and second metal foils 1, 2 are fused with the position of the assumed welding line 43 as a boundary. As a result, the first and second portions of the first and second metal foils 1 and 2 in the surplus region (that is, the region farther from the inclusion 33 than the assumed welding line 43) are the first and second in the coating region. The metal foils 1 and 2 are separated from the respective parts. The first and second metal foils 1 and 2 remaining in the covering region become the first and second jacket materials 34 and 35 (FIG. 6) (welding cutting step).

After this, the pressure in the vacuum chamber is returned to atmospheric pressure. Thereby, the vacuum package 31 having the inclusion 33, the first outer covering material 34, and the second outer covering material 35 is completed. In the space surrounded by the first and second jacket materials 34 and 35, the first and second jacket materials 34 and 35 are sealed together by welding, so that a predetermined vacuum state is maintained. .

Prior to this vacuum sealing method, an experiment for evaluating a sealing state by welding two metal plates stacked on each other was performed. In the experiment, two metal plates overlapped with each other were arranged horizontally, and the metal plates were welded together by irradiating an electron beam from above.

Comparative Example 3
First, two metal plates were joined by a conventional lap welding method in which welding was performed without fusing. In Comparative Example 3, rectangular stainless steel foils having a thickness of 80 μm and vertical and horizontal dimensions of 200 mm were used as the two metal plates. In Comparative Example 3, first, the two stainless steel foils are simply overlapped, and the stainless steel foils are closely adhered to each other at two locations on both sides of the assumed welding line. While being maintained, the stainless steel foils were welded together by concentrated irradiation of electron beams. The adhesion between the stainless steel foils was performed by pressing a pressing member having a width of 10 mm against the stainless steel foil. In Comparative Example 3, the beam current condition is changed within a range of 0.8 mA to 3.0 mA, and the processing speed (moving speed of the support base 37) is changed from 1.0 m / min to 3.0 m / min. The stainless steel foils were welded together in a vacuum environment at a pressure of 4.0 Pa while changing within the range. As a result, when the beam current condition is in the range of 1.5 mA to 2.0 mA and the processing speed condition is in the range of 1.5 m / min to 2.0 m / min, sealing by welding is performed. The stop state became good.

However, since the inclusions 33 are actually inserted between the stainless steel foils, the peripheral portions of the stainless steel foils are bent together while bending the stainless steel foils when the space is not formed in advance by the forming process of the stainless steel foils. It is necessary to adhere. Therefore, it is difficult to completely adhere the peripheral portions of the entire circumference of each stainless steel foil. As a trial, a rectangular parallelepiped inclusion 33 having a thickness of 10 mm and a vertical and horizontal dimension of 100 mm is inserted between two stainless steel foils that have been welded and sealed on three sides in advance, and then the remaining one side is set. The stainless steel foils were pressed by pressing members at two locations on both sides of the wire, and a plurality of gaps of about 30 μm were generated between the peripheral portions of the stainless steel foils.

Therefore, a 50 μm gap was intentionally generated between the stainless steel foils, and welding was performed under the same conditions as above for the beam current and processing speed. As a result, it was impossible to find each condition of the beam current and the processing speed when the sealed state by welding became good. This is because, for example, the temperature condition of the irradiated part that receives the electron beam changes sequentially due to the temperature rise due to welding, and there is no escape from the thermal stress generated during welding in the stainless steel foil. This is considered to be likely to occur.

In addition, when a stainless steel foil having a thickness of 80 μm was formed by drawing in order to create a space in which the inclusions 33 can be stored in advance, the stainless steel foil was cracked due to thinning due to elongation at the drawn portion. It was confirmed that it was difficult to form a stainless steel foil by drawing.

Example 2
Next, the two metal plates were joined to each other by the method of the present embodiment, which was fused while welding. In Example 2, stainless steel foil having a thickness of 80 μm was used as the two metal plates as in the comparative example.

In Example 2, two stainless steel foils are brought into close contact with each other by the inner pressing member 40 at a position closer to the inclusion 33 than the assumed welding line, and the outer pressing member 41 at a position farther from the inclusion 33 than the welding assumed line. The stainless steel foils were brought into close contact with each other, and the stainless steel foil was moved with respect to the optical axis of the electron beam, and the stainless steel foil was irradiated with the electron beam in a concentrated manner. At this time, while the inner pressing member 40 moves at the same speed as the irradiated portion that receives the electron beam, the outer pressing member 41 is not relatively moved at the same position as the electron beam. In this manner, the stainless steel foil was melted at the welding assumed line as a boundary while welding the stainless steel foils along the welding assumed line.

Moreover, in Example 2, the stainless steel foils were welded in a state where a 50 μm gap was intentionally generated between the two stainless steel foils at the position of the assumed welding line. Furthermore, in Example 2, in order to melt while welding two stainless steel foils, each condition of the beam current and the processing speed when welding the stainless steel foils was set to be twice or more that of Comparative Example 3. Here, the beam current was 7.0 mA, and the processing speed was 9.0 m / min.

As a result, in Example 2, even when a gap of 50 μm was generated between the two stainless steel foils, the sealing state by welding of the stainless steel foils was good. This is because the thermal stress generated at the time of welding is moderately dispersed by separating the stainless steel foil in the region farther from the inclusion 33 than the assumed welding line, and excessive heat is moderately generated from the separated stainless steel foil. It is thought that this is because it is released to the outside.

Further, when the finish of the welded part according to Example 2 was observed in detail, it was confirmed that the cross section of the welded part had almost the same form as the finished part of the welded part by so-called worship welding.

In general, if two metal plates having a thickness of about 1 mm or more are used, each metal plate is difficult to bend. It is also possible to perform welding by irradiating the contact end face of each metal plate by irradiating in the vertical direction), but if the thickness of the metal plate is 100 μm or less, the metal plate tends to bend, It becomes difficult to match the irradiation position of plasma or laser to the contact end face of each metal plate. However, according to Example 1, it was confirmed that even if the thickness of each metal plate is 100 μm or less, the finish of the welded portion can be made the same form as the finish of the welded portion by prayer welding.

In such a vacuum packaging method, the first and second metal foils 1 and 2 are heated along the welding assumption line 43 by concentrated irradiation of the beam in a predetermined vacuum environment, and thus along the welding assumption line 43. Since the first and second metal foils 1 and 2 are fused while the first and second metal foils 1 and 2 are welded to each other with the position of the assumed welding line 43 as a boundary, the first and second metal foils Welding between 1 and 2 and vacuum processing of the space surrounded by the first and second metal foils 1 and 2 can be performed simultaneously. Thereby, the number of steps for manufacturing the vacuum package 31 can be reduced, and the productivity of the vacuum package 31 can be improved. Moreover, since excessive heat is dissipated moderately by the fusing of the first and second metal foils 1 and 2, even if the first and second metal foils 1 and 2 are not completely adhered to each other. The first and second metal foils 1 and 2 can be more reliably welded together. Therefore, it is possible to eliminate the work of previously forming the first and second metal foils 1 and 2 by drawing, and the number of processes can be further reduced. Further, it is possible to eliminate the possibility that cracks due to the drawing process occur in the first and second metal foils 1 and 2. Thereby, the productivity of the vacuum package 31 can be further improved.

Further, in the welding fusing process, the position of the outer pressing member 41 is relatively fixed together with the irradiated portion 42, and apparently the irradiated portion 42 and the outer pressing member 41 are attached to the first and second metal foils 1 and 2. Therefore, the thermal stress generated in the first and second metal foils 1 and 2 can be appropriately dispersed, and the first and second metal foils 1 and 2 can be more reliably connected to each other. Can be welded.

In addition, since the first and second metal foils 1 and 2 are stainless steel foils having a thickness of 100 μm or less, the first and second metal foils 1 and 2 can be easily melted while being welded to each other. It is possible to improve the productivity of the vacuum package 31 more reliably.

Embodiment 5 FIG.
In the fourth embodiment, the first and second metal foils 1 and 2 are brought into close contact with each other at the position closer to the inclusion 33 than the assumed welding line 43 by pressing the inner pressing member 40, and the inclusion is located more than the assumed welding line 43. 33, the first and second metal foils 1 and 2 are brought into close contact with each other by the pressing of the outer pressing member 41, but the first and second metals are only pressed by the inner pressing member 41. The foils 1 and 2 may be brought into close contact with each other, and the outer pressing member 41 may be eliminated.

That is, FIG. 9 is a top view showing an installation state during vacuum packaging according to Embodiment 5 of the present invention. FIG. 10 is a cross-sectional view taken along line XX of FIG. The pressing device 38 does not have the outer pressing member 41 but has the inner pressing member 40 similar to that of the fourth embodiment. The configuration of the installation state at the time of other vacuum packaging processing is the same as that of the fourth embodiment.

As for the vacuum packaging method, the first and second metal foils 1 and 2 are brought into close contact with each other by pressing the inner pressing member 40 only at a position closer to the inclusion 33 than the assumed welding line 43 in the close contact process. It has become. Moreover, in the contact | adherence process, the 1st and 2nd metal foils 1 and 2 in the surplus area | region which is separated from the inclusion 33 rather than the welding assumption line 43 are left open | released without press-contacting.

In the welding fusing process, the first and second metal foils 1 and 2 are connected to the assumed welding line 43 while the first and second metal foils 1 and 2 in the surplus area are released in a predetermined vacuum environment. It is designed to heat along. Other procedures are the same as those in the fourth embodiment.

Example 3
Next, in order to evaluate the sealing state by welding of two metal plates stacked on each other, in Example 3, stainless foils having a thickness of 80 μm were joined by the method of the present embodiment. . In Example 3, the two stainless steel foils are brought into close contact with each other by the inner pressing member 40 only at a position closer to the inclusion 33 than the assumed welding line, and the stainless steel foil is moved while moving the stainless steel foil with respect to the optical axis of the electron beam. The electron beam was intensively irradiated. When the electron beam was concentratedly irradiated onto the stainless steel foil, the portion of the metal foil that was farther from the inclusion 33 than the assumed welding line was kept open without being pressed. In this manner, the stainless steel foil was melted at the position of the assumed welding line while welding the stainless steel foils at the position of the assumed welding line.

In Example 3, as in Example 2, the stainless steel foils were welded with a 50 μm gap intentionally generated between the two stainless steel foils at the position of the assumed welding line. Furthermore, in Example 3, welding of stainless steel foils was repeatedly performed while changing each condition of the beam current and the processing speed. As a result, when the beam current condition is in the range of 5.0 mA to 8.0 mA and the processing speed condition is in the range of 5.0 m / min to 11.0 m / min, sealing by welding is performed. The condition became good. In addition, it was confirmed that the finish of the welded portion according to Example 3 was the same as the finish of the welded portion by so-called worship welding.

Actually, a rectangular parallelepiped inclusion 33 having a thickness of 10 mm and a vertical and horizontal dimensions of 100 mm is provided between two stainless steel foils (rectangular stainless steel foil having a thickness of 80 μm) whose three sides are weld-sealed in advance. After the insertion, when the stainless steel foils were welded by the method of the present embodiment at the position of the assumed welding line set based on the remaining one side, it was confirmed that the sealed state by welding was good.

Further, even when the inclusion 33 having a thickness of 10 mm is inserted between two rectangular stainless steel foils having a thickness of 80 μm, and the vacuum packaging body 31 having vertical and horizontal dimensions of 400 mm is produced, It was confirmed that the sealed state of welding by the method of the present embodiment is good.

In such a vacuum packaging method, in the welding fusing process, the first and second metal foils 1 and 2 are welded to the assumed line while the first and second metal foils 1 and 2 in the surplus region are released. Since it heats along 43, the thermal stress which generate | occur | produced at the time of welding can be disperse | distributed more reliably. Thereby, the range of the setting conditions of the beam current and the processing speed at which the sealed state by welding is good can be expanded, and the productivity of the vacuum package 31 can be further improved. Further, in the surplus area, it is not necessary to secure a space for bringing the first and second metal foils 1 and 2 into close contact with each other, so that waste of the first and second metal foils 1 and 2 can be reduced. In addition, the cost can be reduced.

In the fourth and fifth embodiments, before inserting the inclusion 33 between the first and second metal foils 1 and 2, the four sides of the peripheral edge of the first and second metal foils 1 and 2 are inserted. Of these, the metal foil bag is prepared in advance by welding only three sides, but the present invention is not limited to this, and before inserting the inclusion 33 between the first and second metal foils 1 and 2. Without inserting the peripheral portions of the first and second metal foils 1 and 2 and inserting the inclusion 33 between the first and second metal foils 1 and 2 in a predetermined vacuum environment. The entire circumference of the first and second metal foils 1 and 2 may be melted while welding. Further, after the inclusion 33 is inserted between the first and second metal foils 1 and 2 formed by folding one metal foil, the remaining three sides of the first and second metal foils are set to a predetermined shape. Fusing may be performed while welding in a vacuum environment. That is, the first and second metal foils 1, 2 are only part of the periphery of the inclusion 33 when the inclusion 33 is viewed along the direction in which the first and second metal foils 1, 2 face each other. Are joined in advance, and after the inclusion 33 is inserted between the first and second metal foils 1 and 2, the first and second metal foils 1 and 2 are joined together around the inclusion 33. The assumed welding line may be set in the remaining part excluding the part, and the first and second metal foils may be inserted before the inclusion 33 is inserted between the first and second metal foils 1 and 2. After inserting the inclusion 33 between the first and second metal foils 1 and 2 without joining the first and second metal foils, an assumed welding line may be set around the entire circumference of the inclusion 33. Good.

In each of the above embodiments, the electron beam is concentratedly irradiated on one of the first and second metal foils 1 and 2 that is stacked on the upper side. Of the two metal foils 1 and 2, the other metal foil stacked on the lower side may be concentratedly irradiated with an electron beam. In this case, the electron beam is irradiated from the lower side to the upper side of the support table 37, and the support tables 3 and 37 are arranged avoiding the optical axis of the electron beam.

In each of the above embodiments, the first and second metal foils 1 and 2 are heated by irradiation with an electron beam. However, the present invention is not limited to an electron beam, and may be a laser beam, for example. . In this case, a laser welding machine (beam generator) is installed outside the vacuum chamber, and glass or the like that transmits the laser beam is installed in the vacuum chamber. As a result, the laser beam that has passed through the glass from the laser welding machine can be radiated to one of the first and second metal foils 1 and 2 in the vacuum chamber, and the first and second metal foils 1 and 2 can be irradiated. Can be heated.

When a laser welder is installed outside the vacuum chamber, the support base 37 may be moved while the laser welder is fixed to the vacuum chamber, or the laser is fixed with the support base 37 fixed to the vacuum chamber. The welder may be moved. Further, a laser welder may be installed in the vacuum chamber. Examples of the laser beam include a yag (yttrium, aluminum, garnet) laser and a carbon dioxide gas laser.

Further, the vacuum packaging method for vacuum packaging the inclusion 33 is performed by welding the first and second metal foils 1 and 2 to each other by the beam welding method of the first to third embodiments. A method of vacuum packaging the inclusion 33 inserted between the foils 1 and 2 may be used. That is, the insertion step of inserting the inclusion 33 between the first and second metal foils 1 and 2 and the metal foil lamination step, the adhesion step and the welding fusing step of the first to third embodiments performed after this insertion step are performed. It may be a vacuum packaging method provided. In this case, in the metal foil laminating step of the beam welding methods of the first to third embodiments, the inclusion 33 is mainly formed when the support base 3 is viewed along the direction in which the first and second metal foils 1 and 2 overlap. The first and second metal foils 1 and 2 are arranged with respect to the support base 3 so as to exist in the region of the mounting surface 7. As described above, if the beam welding method of the first to third embodiments is applied to the vacuum packaging method for vacuum packaging the inclusions 33, the finish of the welding between the first and second metal foils 1 and 2 is further improved. It is possible to further improve the sealed state of the inclusion 33 in the container 32 obtained by welding the first and second metal foils 1 and 2 together.

Embodiment 6 FIG.
FIG. 11 is a cross-sectional view showing a vacuum package according to Embodiment 6 of the present invention. In the figure, the inclusion 33 is a core material having a plurality of fiber sheets 51 laminated in the direction in which the first and second jacket materials 34 and 35 face each other (that is, the thickness direction of the vacuum package 31). It is said that. The fiber sheet 51 is a sheet made of fibers made of an inorganic material (for example, glass). The fibers constituting the fiber sheet 51 are single diameter fibers in the range of about 0.8 μm to 15 μm or mixed fibers having different diameters. The thickness of the fiber sheet 51 is about 0.2 mm to 3.0 mm. That is, the vacuum package 31 is a vacuum heat insulating material having the inclusion 33 having a plurality of fiber sheets 51 as a core material. A space surrounded by the first and second jacket materials 34 and 35 of the vacuum heat insulating material is in a vacuum state in a range of 0.1 Pa to 3.0 Pa.

The heat that travels through the vacuum heat insulating material moves around the outside of the core material while being transmitted through the core material and the first and second jacket materials 34 and 35 that surround the core material. There is heat. As described above, when the thickness of the first and second jacket materials 34 and 35 increases, the heat flow that moves around the outside of the core material increases, so that the heat insulating performance of the entire vacuum heat insulating material significantly decreases. Resulting in. Accordingly, the heat insulation performance of the vacuum heat insulating material can be improved as the thickness of the first and second outer covering materials 34 and 35 is reduced.

外 A general vacuum insulation material is an aluminum laminate sheet. The thickness of the aluminum foil constituting the aluminum laminate sheet is usually the thinnest and about 6 μm thick. If stainless steel, which has a lower thermal conductivity than aluminum, is used as the outer cover material of the vacuum heat insulating material, the thickness of the outer cover material can be made larger than when the outer cover material of the vacuum heat insulating material is aluminum. . Therefore, in order to obtain a thermal conductivity equal to or higher than that of an aluminum foil having a thickness of 6 μm, the thickness of the stainless steel foil may be set to about 80 μm or less.

In this example, the first and second jacket materials 34 and 35 are made of a stainless steel foil having a thickness of 80 μm. Therefore, the heat insulating performance of the vacuum package (vacuum heat insulating material) 31 is equivalent to that of a general high performance vacuum heat insulating material.

Actually, after making 30 cores by laminating 30 glass fiber sheets with thickness of 0.5mm and length and breadth dimensions of 400mm respectively, two stainless steels with thickness of 80μm welded on 3 sides beforehand A core material was inserted between the foils, and the remaining one side was welded and sealed under a vacuum environment of 1.0 Pa, thereby producing a vacuum heat insulating material. As a prototype vacuum packaging method, the method of Embodiment 2 was used.

When the thermal conductivity of the prototype vacuum heat insulating material was measured, a value of 0.0025 W / mK was obtained. From this, it was confirmed that the heat insulation performance of the prototyped vacuum heat insulating material is the same as that of the high performance vacuum heat insulating material.

Thus, the vacuum package 31 can be used as a vacuum heat insulating material by using the core material having a plurality of laminated fiber sheets 51 as the inclusions 33.

Also, in general vacuum heat insulating materials, moisture and air easily enter from the welded part of the aluminum laminate sheet over time, so it is necessary to insert a gas adsorbent inside the vacuum heat insulating material. In the vacuum heat insulating material according to the embodiment, since the sealing state by welding of the stainless steel foils constituting the first and second jacket materials 34 and 35 can be improved, the first and second jacket materials Intrusion of air and moisture into the space surrounded by 34 and 35 can be prevented more reliably, and a gas adsorbent can be dispensed with.

In addition, since the first and second jacket materials 34 and 35 are made of stainless steel foil, the first and second jacket materials 34 and 35 are formed in comparison with the case where the first and second jacket materials are made of an aluminum laminate sheet. The heat resistance performance of the outer covering materials 34 and 35 can be improved. Therefore, when the core material is composed of glass fiber, the heat resistance of the entire vacuum heat insulating material can be improved to the heat resistance of glass fiber. That is, when an aluminum laminate sheet is used for the first and second jacket materials, the heat resistance temperature of the aluminum laminate sheet is low, so the maximum usable temperature of the vacuum heat insulating material is about 100 ° C. or less. By configuring the first and second jacket materials with stainless steel foil, the maximum usable temperature of the vacuum heat insulating material can be increased to about 300 ° C. which is the heat resistant temperature of the glass fiber. Furthermore, if the core material is composed of ceramic fibers instead of glass fibers, the maximum usable temperature of the vacuum heat insulating material can be increased to about 500 ° C.

In the fourth to sixth embodiments, the three sides of the rectangular metal foil are welded in a bag shape in advance, and the inclusion 33 is inserted from the remaining opening and then vacuum sealed. Thereafter, when the vacuum chamber is opened to the atmosphere, the entire container is subjected to a pressure of approximately 1 atm. Therefore, distortion is likely to occur in the packaging material and the pre-welded location, which causes cracks. For this reason, in order to protect a prior welding location, at least the first metal foil 1 and the second metal foil 2 that sandwich the inclusion 33 and the previous welding location are sandwiched from above and below with, for example, a pressure plate. This makes it possible to prevent this.

Further, the vacuum heat insulating material (vacuum package) 31 may be produced by a vacuum packaging method to which the beam welding method of the first to third embodiments is applied. That is, the insertion step of inserting the inclusion 33 between the first and second metal foils 1 and 2 and the metal foil lamination step, the adhesion step and the welding fusing step of the first to third embodiments performed after this insertion step are performed. You may produce the vacuum heat insulating material 31 with the provided vacuum packaging method. If it does in this way, the finish of welding of the 1st and 2nd metal foils 1 and 2 can be made still more favorable, and the accommodation obtained by welding of the 1st and 2nd metal foils 1 and 2 mutually The sealed state of the core member 33 in the body 32 can be further improved. Therefore, the heat insulation performance of the vacuum heat insulating material 31 can be further improved.

1 1st metal foil, 2nd metal foil, 3,37 support base, 6 beam groove, 7 main mounting surface, 8 follower mounting surface, 10, 42 irradiated part, 11, 43 welding assumed line, 21, 31 Vacuum packaging body (vacuum heat insulating material), 22, 32 container, 23, 33 inclusion (core material).

Claims (11)

A first metal foil and a second metal foil stacked on the first metal foil are placed on the main mounting surface and the secondary mounting surface adjacent to each other of the support base, respectively, and the first and second metals When the support base is viewed along the direction in which the foils overlap, an assumed welding line set between the main mounting surface and the secondary mounting surface crosses the planes of the first and second metal foils. A metal foil laminating step in which the first and second metal foils are disposed,
The first and second metal foil portions placed on the main placement surface are connected to each other on the assumed welding line in a state where the first and second metal foil portions placed on the follower surface are released. And a contact step that adheres along the surface, and after the contact step, the first and second metal foils are heated by concentrated irradiation of a beam in a predetermined vacuum environment, thereby placing the first and second metal foils on the main mounting surface. A welding fusing step of cutting off the first and second metal foil portions placed on the follower surface while welding the first and second metal foil portions along the assumed welding line. A beam welding method characterized by comprising: A beam groove is provided between the main mounting surface and the secondary mounting surface,
The welding assumption line is located within a range of a width of the beam groove when the support base is viewed along a direction in which the first and second metal foils overlap. The beam welding method described in 1. 3. The beam welding method according to claim 1, wherein the first and second metal foils are stainless steel foils having a thickness of 100 μm or less. The beam welding method according to any one of claims 1 to 3, wherein the beam is an electron beam. The output current of the electron beam is I [A], the average thickness of each of the first and second metal foils is t [mm], and the irradiated portion of the electron beam is along the assumed welding line. When the feed speed when moving is v [m / min],
a1 ≦ I / (t · v) ≦ a2
The welding fusing process is performed under conditions that satisfy the relational expression represented by
The metal type lower limit value P and the metal type upper limit value are individually specified in correspondence with the types of metals constituting the first and second metal foils,
When the materials of the first and second metal foils are the same type of metal, the metal type lower limit P corresponding to the type of metal constituting the first and second metal foils is set to the value of a1. 5. The beam welding method according to claim 4, wherein the metal type upper limit value Q corresponding to the type of metal constituting the first and second metal foils is set to the value a <b> 2. The output current of the electron beam is I [A], the average thickness of each of the first and second metal foils is t [mm], and the irradiated portion of the electron beam is along the assumed welding line. When the feed speed when moving is v [m / min],
a1 ≦ I / (t · v) ≦ a2
The welding fusing process is performed under conditions that satisfy the relational expression represented by
The metal type lower limit value P and the metal type upper limit value Q are individually specified corresponding to the types of metals constituting the first and second metal foils,
When the materials of the first and second metal foils are dissimilar metals, the metal type lower limit values P respectively corresponding to the types of metals constituting the first and second metal foils, and Any one of the average values of the metal type lower limit values P is set to the value of the a1, and each of the metal type upper limit values Q corresponding to the types of metals constituting the first and second metal foils, and 5. The beam welding method according to claim 4, wherein any one of the average values of the metal type upper limit values Q is set to the value a <b> 2. P = 5, Q = 15 when the metal type is stainless steel and iron-based, P = 100, Q = 175 when copper-based, P = 5, Q = 30 when titanium-based, titanium 7. The beam welding method according to claim 5, wherein P = 2.5 and Q = 45 in the case of a system. The said welding fusing process WHEREIN: While reducing the irradiation amount of the said electron beam, the to-be-irradiated part of the said electron beam is moved along the said welding assumption line, It is any one of Claim 1 thru | or 7 characterized by the above-mentioned. The beam welding method described in 1. An insertion step of inserting inclusions between the first and second metal foils;
After the insertion step, a welding assumption line is set around the inclusion when the inclusion is viewed along a direction in which the first and second metal foils face each other, and the intervention is more than the welding assumption line. An adhesion step for bringing the first and second metal foils into close contact under a predetermined vacuum environment only at a position close to an object, and the first and second metals under the predetermined vacuum environment after the contact step By heating the foil along the welding assumption line by concentrated irradiation of the beam, the first and second metal foils in the covering region on the inclusion side than the welding assumption line are used as the welding assumption line. A welding fusing step for cutting off the first and second metal foil portions in the surplus area farther from the inclusion than the assumed welding line while welding along the welding line. . The interposition inserted between the first and second metal foils by welding the first and second metal foils by the beam welding method according to any one of claims 1 to 8. A vacuum packaging method for vacuum packaging an object,
In the metal foil laminating step, the first and second metal foils are arranged such that the inclusions are present in the region of the main mounting surface when the support table is viewed along the direction in which the first and second metal foils overlap. A vacuum packaging method comprising arranging a second metal foil. A vacuum heat insulating material obtained by vacuum packaging the inclusions by the vacuum packaging method according to claim 9 or 10,
In the state which has the core which is the said inclusion which has a fiber sheet, and the said 1st and 2nd metal foil welded mutually, and the said core is inserted between the said 1st and 2nd metal foil A vacuum heat insulating material comprising a container for sealing the core material.

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