U.S. patent application number 14/595733 was filed with the patent office on 2015-07-16 for vacuum heat-insulating container.
The applicant listed for this patent is Thermos K.K., Thermos L.L.C.. Invention is credited to Yasuhiro Kurabe, Shin Matsuyama.
Application Number | 20150197390 14/595733 |
Document ID | / |
Family ID | 52339028 |
Filed Date | 2015-07-16 |
United States Patent
Application |
20150197390 |
Kind Code |
A1 |
Kurabe; Yasuhiro ; et
al. |
July 16, 2015 |
VACUUM HEAT-INSULATING CONTAINER
Abstract
A metallic vacuum heat-insulating container having a double wall
structure is described. The metallic vacuum heat-insulating
container includes an outer container having an outer cylinder and
a metallic bottomed cylindrical bottom cover. The outer cylinder
has opened upper and lower ends, a barrel portion between the upper
and lower ends, a mouth portion having an inner diameter which is
smaller than that of the barrel portion, and a stepped portion
whose diameter is smaller than the diameter of the barrel portion
which is provided on a side surface on a lower portion of the outer
cylinder. An opening portion in an upper portion of the metallic
bottomed cylindrical bottom cover, which has a diameter
substantially the same as the diameter of the barrel portion of the
outer cylinder, is allowed to abut on the stepped portion, and the
abutting portions are integrated by welding.
Inventors: |
Kurabe; Yasuhiro;
(Tsubame-shi, JP) ; Matsuyama; Shin; (Tsubame-shi,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Thermos L.L.C.
Thermos K.K. |
Schaumburg
Niigata-ken |
IL |
US
JP |
|
|
Family ID: |
52339028 |
Appl. No.: |
14/595733 |
Filed: |
January 13, 2015 |
Current U.S.
Class: |
220/592.27 |
Current CPC
Class: |
B65D 81/3841 20130101;
A47J 41/0077 20130101 |
International
Class: |
B65D 81/38 20060101
B65D081/38 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 15, 2014 |
JP |
2014-004865 |
Claims
1. A metallic vacuum heat-insulating container, comprising: a
double wall structure in which a metallic bottomed cylindrical
inner container and a metallic bottomed cylindrical outer container
are integrated in respective mouth portions, air is discharged from
a void between the inner container and the outer container from a
discharge hole provided on the bottom surface of the outer
container, wherein the discharge hole is sealed with a
vacuum-sealing material to be made into a vacuum heat-insulating
layer; the outer container includes an outer cylinder and a
metallic bottomed cylindrical bottom cover; the outer cylinder
includes: opened upper and lower ends, a barrel portion between the
upper end and the lower end, the barrel portion defined by a
diameter, a mouth portion, which is an opening portion of the upper
end, having an inner diameter which is smaller than the diameter of
the barrel portion, and, a stepped portion having a diameter
smaller than diameter of the barrel portion positioned on a side
surface on a lower portion of the outer cylinder; an opening
portion in an upper portion of the metallic bottomed cylindrical
bottom cover, which has a diameter substantially identical to the
diameter of the barrel portion of the outer cylinder, is allowed to
abut the stepped portion, and, the abutting portions are integrated
by welding, thereby creating a sealed space therebetween.
2. The metallic vacuum heat-insulating container according to claim
1, further comprising at least one or more reinforcing stepped
portions on the bottom surface of the bottom cover.
3. The metallic vacuum heat-insulating container according to claim
1, wherein the sealed space contains a buffering material.
4. The metallic vacuum heat-insulating container according to claim
1, wherein the sealed space contains a magnet.
5. The metallic vacuum heat-insulating container according to claim
1, wherein the sealed space reduces or prevents corrosion of the
outer container and the metallic bottomed cylindrical bottom
cover.
6. The metallic vacuum heat-insulating container according to claim
1, wherein the sealed space is tightly sealed.
7. The metallic vacuum heat-insulating container according to claim
1, wherein the sealed space is tightly sealed to prevent water from
infiltrating into the sealed space.
Description
RELATED APPLICATIONS
[0001] This application claims priority to Japanese Patent
Application No. 2014-004865 filed Jan. 15, 2014, which is hereby
incorporated by reference in its entirety.
FIELD OF INVENTION
[0002] The present invention relates to a vacuum heat-insulating
container in which an outer container and a bottom cover are welded
together.
BACKGROUND OF THE INVENTION
[0003] Since a bottom cover of a metallic vacuum heat-insulating
container in the related art is only externally fitted into an
outer container, there is a concern that metal corrosion may occur
due to infiltration of water into a void between the outer
container and the bottom cover when the container is washed.
Further, there is another concern that heat-insulating performance
is degraded due to vacuum breaking occurring if the corrosion
progresses. As a structure for preventing corrosion, as disclosed
in Japanese Unexamined Patent Application, First Publication No.
2000-316729, a structure is known that prevents infiltration of
water into a void between the outer container and the bottom cover
by welding the bottom cover to the outer container. However, in
this structure, a brazing material that seals a discharge hole for
a vacuum treatment is exposed to the outer surface of the outer
container.
[0004] For this reason, in Japanese Unexamined Patent Application,
First Publication No. 2000-316729, a brazing material is protected
by bonding a cover sheet thereto. However, by only bonding a cover
sheet to a brazing material, it is difficult to prevent
infiltration of water at the time of washing the outer container.
Accordingly, metal corrosion of the container still may occur in
the case where water infiltrates the space between the cover and
the container.
[0005] Moreover, since the cover sheet is mainly formed of a
synthetic resin, there is a possibility that the cover sheet is
peeled off from the brazing material because of insufficient heat
resistance during washing or drying (for example, at the time of
using a dishwasher or a dish dryer) or sterilizing (for example, at
the time of using a sterilized cabinet) in a high-temperature
environment. In addition, since it is difficult to protect the
brazing material from an impact caused by a fall or the like only
by means of a cover sheet made of a synthetic resin, there is a
concern that the brazing material may be broken and heat-insulating
performance may be degraded.
[0006] In a container disclosed in Japanese Patent No. 5146926,
water does not infiltrate into a void between a protective plate
and an outer container, but, because the protective plate is made
of a synthetic resin or the like, there is a possibility that heat
resistance or durability is not sufficient, for example, to
withstand an impact caused by a fall.
[0007] Meanwhile, in Japanese Unexamined Patent Application, First
Publication No. 2001-087144, a plate material made of stainless
steel is adhered as a protective member, but heat resistance is
insufficient depending on the kind of adhesive so that the
protective member may be peeled off when used in a high-temperature
environment. Further, welding the protective member to the bottom
surface of an outer container can be considered, but it is
difficult to weld a plate member because the bottom surface of the
outer container tends to be easily buckled by a vacuum treatment
and the flatness is insufficient.
SUMMARY OF THE INVENTION
[0008] Accordingly, a metallic vacuum heat-insulating container is
provided that prevents corrosion of a container due to infiltration
of water into a void between an outer container and a bottom cover,
protects a vacuum-sealing material from an impact caused by a fall
or the like without a protective body being peeled off even in a
high-temperature environment, and has excellent productivity.
[0009] That is, according to an aspect of the invention, a metallic
vacuum heat-insulating container is provided that has a double wall
structure in which a metallic bottomed cylindrical inner container
and a metallic bottomed cylindrical outer container are integrated
in respective mouth portions. In such container, air may be
discharged from the void between the inner container and the outer
container via a discharge hole provided on the bottom surface of
the outer container. The discharge hole may be sealed with a
vacuum-sealing material. The inner container and outer container,
together with the vacuum sealing material, may form a vacuum
heat-insulating layer. The outer container may include a
cylindrical outer cylinder whose upper end and lower end are both
opened. The mouth portion of the outer container, an opening
portion of the upper end, may be smaller than a barrel portion. A
disk-like outer bottom, which is integrated by welding, may be
provided on the lower end of the outer cylinder. A stepped portion
whose diameter is smaller than the diameter of the barrel portion
may be provided on a side surface in the lower portion of the
barrel portion of the outer cylinder. An opening portion of an
upper portion of a metallic bottomed cylindrical bottom cover,
which has a diameter substantially the same as the diameter of the
barrel portion, is allowed to abut the stepped portion. The
abutting portions are integrated by welding.
[0010] The metallic vacuum heat-insulating container according to a
second aspect of the invention may include at least one or more
reinforcing stepped portions on the bottom surface of the bottom
cover.
[0011] According to the first aspect of the invention, since the
stepped portion having a diameters smaller than that of the barrel
portion is provided on the side surface of the bottom portion of
the outer container, the opening portion in the upper portion of
the metallic bottomed cylindrical bottom cover is allowed to abut
on the stepped portion, and the abutting portions are integrated by
welding, water does not infiltrate into a void between the outer
container and the bottom cover. Also, the vacuum-sealing material
can be strongly protected because the bottom cover is made of a
metal, and the bottom cover serving as a protective body is not
peeled off even in a high-temperature environment because of the
integration by welding. Further, the productivity can be improved
by welding the opening portion of the bottom cover to the stepped
portion on the side surface which is hardly or not at all buckled
by the vacuum treatment.
[0012] According to the second aspect of the invention, since at
least one or more reinforcing stepped portions may be included on
the bottom surface of the bottom cover, the void between the outer
container and the bottom cover is tightly sealed by welding, and it
is possible to prevent the bottom cover from being swollen even
when the inner pressure of the tightly sealed space is increased in
a high-temperature environment. Further, there is an effect of
preventing deformation due to an impact caused by a fall or the
like.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a cross-sectional view illustrating a metallic
vacuum heat-insulating container according to a first
embodiment.
[0014] FIG. 2 is an enlarged cross-sectional view illustrating a
main portion of the metallic vacuum heat-insulating container of
FIG. 1.
[0015] FIG. 3 is a perspective view of the metallic vacuum
heat-insulating container according to the first embodiment.
[0016] FIG. 4 is a front view of the metallic vacuum
heat-insulating container according to the first embodiment.
[0017] FIG. 5 is a top view of the metallic vacuum heat-insulating
container according to the first embodiment.
[0018] FIG. 6 is a bottom view of the metallic vacuum
heat-insulating container according to the first embodiment.
[0019] FIG. 7 is a cross-sectional view of a metallic vacuum
heat-insulating container according to a second embodiment.
[0020] FIG. 8 is a cross-sectional view illustrating a metallic
vacuum heat-insulating container according to a third
embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0021] Preferred embodiments of the present invention will be
described with reference to the accompanying drawings. In addition,
the embodiments described below do not limit the contents of the
aspects of the present invention. Further, all configurations
described below are not necessarily required for the present
invention.
First Embodiment
[0022] Hereinafter, FIGS. 1 to 6 illustrate a metallic vacuum
heat-insulating container according to a first embodiment of the
present invention. A metallic vacuum heat-insulating container 1
includes an outer container 4 formed by welding an outer bottom 3
to the bottom of an outer cylinder 2; a bottomed cylindrical inner
container 5 disposed in the inside of the outer container 4; a
cylindrical bottom cover 7 welded to a side surface 6 in the lower
portion of the outer cylinder 2; and a lid unit 9 that opens and
closes a mouth portion 8 of the inner container and is detachably
mounted on the upper portion of the outer container 4. The inner
container 5, the outer container 4, and the bottom cover 7 are
formed of stainless steel, for example, SUS304 (18-8 stainless
steel).
[0023] The outer diameter of the inner container 5 is formed to be
smaller than the inner diameter of the outer container 4 since the
inner container 5 is disposed in the outer container 4. Further, in
order to improve heat-insulating performance as a heat-insulating
container, metal plating using a metal with a small radiation rate
or winding of a foil is provided for an outer surface 10 of the
inner container as preventive radiation countermeasures.
[0024] The inner container 5 is inserted from the opening portion
11 in the lower portion of the outer container 4, and the mouth
portion 8 of the inner container and a mouth portion 12 of the
outer container which is an opening portion on the upper end of the
outer container are bonded by welding over the whole circumference.
The outer bottom 3 is bonded to the opening portion 11 in the lower
portion of the outer container 4 accommodating the inner container
5 over the whole circumference by welding and a container having a
double wall structure in which the inner container 5 and the outer
container 4 are integrated is formed. Further, a vacuum
heat-insulating layer 15 is formed in the void between the inner
container 5 and the outer container 4 through a vacuum treatment in
which air in a void between the inner container 5 and the outer
container 4 is discharged through a discharge hole 13. The
discharge hole 13 is formed in the center of the outer bottom 3 and
communicates the inside and the outside of the outer container 4.
The discharge hole 13 is sealed with a vacuum-sealing material 14.
Further, a metal brazing material formed of Sn or a Sn alloy
containing Ag, Cu, Ni, Bi, or Zn, or a glass brazing material is
used for the vacuum-sealing material 14.
[0025] In the center of the outer bottom 3, a shallow outer bottom
concave portion 16, which is also flat and circular, is formed on
the vacuum heat-insulating layer 15 side. The outer bottom concave
portion 16 has a smaller diameter when compared to the diameter of
the outer bottom 3 and has a function of preventing the
vacuum-sealing material 14 from melting during a vacuum-sealing
process from flowing out to the periphery.
[0026] An annular outer bottom stepped portion 17 having a bottom
which is shallower than that of the outer bottom concave portion 16
is formed on the outside of the outer bottom concave portion 16.
When the outer bottom concave portion 16 and the outer bottom
stepped portion 17 are provided, the strength of the outer bottom 3
is increased compared to a case where the outer bottom is a flat
plate and decreasing buckling of the outer bottom 3 during the
vacuum treatment. Further, when the strength of the outer bottom 3
is increased, the outer diameter of the outer bottom stepped
portion 17 can be changed. In addition, a plurality of outer bottom
stepped portions 17 may be provided.
[0027] Further, an annular outer bottom surface portion 18 is
formed on the outside of the outer bottom stepped portion 17, a
tapered portion 19 whose diameter becomes larger toward the upper
side is formed on the further outside thereof, and an annular
narrow width flat portion 20 is formed on the still further outside
thereof. An outer bottom outermost portion 22 directed vertically
downward so as to be parallel to a side surface lowermost portion
21 of the outer cylinder 2 is formed on the outside of the narrow
width flat portion 20. The outer bottom outermost portion 22 is an
outermost portion of the outer bottom 3, and the end surface is
aligned with the side surface lowermost portion 21 of the outer
cylinder 2 and integrated by welding. Further, the diameter of the
side surface lowermost portion 21 is larger than that of the barrel
portion of the inner container 5.
[0028] A gas adsorber 23 is positioned by welding on the surface of
the vacuum heat-insulating layer 15 side of the outer bottom 3, and
the gas adsorber 23 adsorbs gas generated from the vacuum
heat-insulating layer 15. A welding trajectory of the gas adsorber
23 is formed on the outer bottom 3, but the welding trajectory does
not appear from the appearance of the metallic vacuum
heat-insulating container 1 which is a product because the welding
trajectory is covered by the bottom cover 7. Therefore, the gas
adsorber 23 may be positioned in any of the outer bottom stepped
portion 17, the outer bottom surface portion 18, the tapered
portion 19, and the narrow width flat portion 20 as long as the gas
adsorber 23 is not in a position capable of blocking the discharge
hole 13.
[0029] The bottom cover 7 has a cylindrical shape having an opening
portion 24 in the upper portion thereof and a reinforcing stepped
portion 26 which is upwardly convex is provided on the bottom
surface 25. The reinforcing stepped portion 26 is flat and circular
and the diameter thereof is smaller than that of the inner
container 5. Further, the surface other than the reinforcing
stepped portion 26 in the bottom surface 25 is a surface on which
the container is placed and is formed flat for stable placing of
the container.
[0030] Since the strength of the bottom cover 7 is increased by
forming the reinforcing stepped portion 26 compared to a case where
the bottom cover is a flat plate, it is possible to prevent the
bottom cover 7 from being swollen even when the metallic vacuum
heat-insulating container 1 is placed in a high-temperature
environment and the inner pressure of a tightly sealed space 27
formed in the void between the outer container 4 and the bottom
cover 7 is increased. Further, deformation of the bottom cover 7
due to an impact caused by a fall or the like can be prevented. In
addition, the metallic vacuum heat-insulating container 1 can be
stably placed, the outer diameter of the reinforcing stepped
portion 26 can be changed when the strength of the bottom cover 7
can be increased, and a plurality of the reinforcing stepped
portions 26 may be provided.
[0031] A stepped portion 29 whose diameter is smaller than that of
a barrel portion 28 and larger than that of the side surface
lowermost portion 21 is formed on the side surface 6 in the lower
portion of the outer container 4. The inner surface of the opening
portion 24 of the bottom cover 7 is fitted on the outer surface of
the stepped portion 29 such that the inner surface of the opening
portion 24 abuts on the outer surface of the stepped portion 29.
Since the diameter of the stepped portion 29 of the outer container
4 is formed to be small by a thickness of a barrel portion 30 of
the bottom cover serving as a side wall of the bottom cover 7, when
the outer container 4 and the bottom cover 7 are fitting together,
the barrel portion 28 of the outer container 4 and the barrel
portion 30 of the bottom cover become flush or the diameter of the
barrel portion 30 of the bottom cover is smaller than that of the
barrel portion 28. In addition, the width of a difference in step
of the stepped portion 29 in the radial direction is formed to be
narrow such that buckling is unlikely to occur during the vacuum
treatment.
[0032] A first bent portion 32 is formed between the barrel portion
28 and the stepped portion 29 of the outer container 4, and the
bottom cover 7 is positioned by fitting on the first bent portion
32 such that the bottom cover 7 abuts on the first bent portion 32.
Moreover, the outer container 4 and the bottom cover 7 are
integrated with each other by an end portion 31 and the first bent
portion 32 being welded and bonded to each other.
[0033] Since the end portion 31 and the first bent portion 32 are
welded over the entire circumference of the end portion 31 and the
first bent portion 32 without a gap, it is possible to prevent
infiltration of water into a void between the outer container 4 and
the bottom cover 7. Accordingly, corrosion of the outer container
4, the bottom cover 7, and the vacuum-sealing material 14 in the
tightly sealed space 27 due to infiltration of water can be
prevented and/or reduced.
[0034] Moreover, since the bottom cover 7 is bonded to the outer
container 4 by welding and the vacuum-sealing material 14 is
completely covered by the bottom cover 7, the vacuum-sealing
material 14 is protected from an impact caused by a fall or the
like. Therefore, a member for protecting the vacuum-sealing
material 14 such as a protective plate for blocking the outer
bottom concave portion 16 formed on the outer bottom 3 becomes
unnecessary and thus reduction in production cost and
simplification of working processes can be realized.
[0035] Further, a second bent portion 33 formed between the stepped
portion 29 and the side surface lowermost portion 21 and the side
surface lowermost portion 21 have diameters smaller than that of
the stepped portion 29. The bottom cover 7 only abuts on the
stepped portion 29 and the first bent portion 32 and does not abut
on other portions in a state in which the bottom cover 7 is fitted
on the outer container 4. For this reason, it is possible to
prevent a buckled portion from being brought into contact with the
side surface lowermost portion 21 and to protect a welded portion
between the side surface lowermost portion 21 and the outer bottom
outermost portion 22 because of the presence of the tightly sealed
space 27 even in a case where the outer bottom 3 is buckled to the
inside due to an impact caused by a fall or the like. Similarly, it
is possible to prevent the buckled portion from being brought into
contact with the vacuum-sealing material 14 and to protect the
vacuum-sealing material 14.
[0036] During the vacuum treatment applied to the void between the
inner container 5 and the outer container 4, the outer bottom 3
whose area of the plane is large tends to be easily buckled and
flatness for performing a welding treatment after the vacuum
treatment becomes insufficient. On the contrary, in the present
embodiment, the bottom cover 7 is welded not to the outer bottom 3,
but the side surface 6 in the lower portion. The reason for this is
that the plane for the welding treatment can be ensured even after
the vacuum treatment is completed so that work stability and
productivity in the welding process are excellent because the side
surface 6 in the lower portion is cylindrical while the outer
bottom 3 is disk-like and thus the side surface is unlikely to
buckle.
[0037] In a case where food and drink are stored in the metallic
vacuum heat-insulating container 1 according to the present
embodiment, the metallic vacuum heat-insulating container 1 may be
washed or dried using a dishwasher or a dish dryer after being used
is exposed to a high-temperature environment for a certain amount
of time for sterilization using a sterilized cabinet. Further, the
metallic vacuum heat-insulating container 1 of the present
embodiment may be used in a low-temperature environment, for
example, outdoors in winter because of portability of the metallic
vacuum heat-insulating container. Even in such a case, since the
outer container 4 and the bottom cover 7 are bonded to each other
by welding, durability in a low or high-temperature environment is
sufficient and thus peeling of the bottom cover 7 from the outer
container 4 caused by the temperature can be prevented.
[0038] The lid unit 9 includes a cylinder lid body 35 having a top
surface 34 and a plug body 36 disposed in the inside of the lid
body 35 and having a water-stopping function. The lid body 35 and
the plug body 36 are separately configured, the mouth portion 8 of
the inner container is closed by the plug body 36, and the plug
body 36 is brought into close contact with the inner container 5 by
screwing the lid body 35 to the outer container 4, and then the
water-stopping function is exhibited. Moreover, the lid body 35 and
the plug body 36 may be a single piece construction.
[0039] The lid body 35 is made of a synthetic resin, the outer
diameter thereof is larger than that of the barrel portion 28 of
the outer container 4, and the cross-section has an inverted U
shape. Further, a male screw 37 is formed on the inner side surface
of the lid body 35 and the lid body 35 is mounted on the outer
container 4 by threading the male screw 37 to a female screw 39
formed on the outer side surface 38 in the upper portion of the
outer container 4. The diameter of the outer side surface 38 in the
upper portion is formed to be smaller than that of the barrel
portion 28.
[0040] Since a lid body convex portion 40, which is downwardly
convex, is formed on the top surface 34 of the lid body 35, when
the lid body 35 is screwed to the outer container 4, the lid body
convex portion 40 abuts on a receiving portion 41 formed on the
plug body 36 and presses the plug body 36 downwardly. Abutting
surfaces 42 between the lid body convex portion 40 and the
receiving portion 41 are respectively flat and the lid body convex
portion 40 is configured such that the lid body convex portion 40
can press the receiving portion 41 vertically downward. Moreover,
the lid body convex portion 40 is formed of a silicone resin.
Further, the lid body convex portion 40 and the receiving portion
41 may be respectively provided in plural.
[0041] A vent hole 43 ventilating the inside and the outside of the
inner container 5 is formed in the center of the receiving portion
41. The vent hole 43 is blocked by the lid body convex portion 40
that abuts on the receiving portion 41 when the lid body 35 is
mounted on the outer container 4 and the inner container 5 is
tightly sealed. In addition, when the lid body 35 is peeled off
from the outer container 4, the vent hole 43 is opened and the
inside and the outside of the inner container 5 is ventilated.
Accordingly, the inner pressure of the inner container 5 becomes
equivalent to the atmospheric pressure so that the plug body 36 can
be easily detached.
[0042] Since the plug body 36 is bottomed and cylindrical and the
receiving portion 41 formed on a bottom portion 44 has an upwardly
convex shape, the cross-section has a W shape. Further, the
diameter of the lower portion of the plug body 36 is smaller than
that of the upper portion thereof, and a water-stopping member 46
exhibiting a water-stopping function by being brought into close
contact with the inner container 5 is fitted on the side surface in
the lower portion of the plug body 36. The water-stopping member 46
covers an outer periphery 45 on the bottom surface of the plug body
36. In addition, the water-stopping member 46 is a so-called rubber
packing formed of silicone rubber. Moreover, the plug body 36 may
be made of a synthetic resin.
[0043] A small concave portion 47 and a small convex portion 48
positioned below the small concave portion 47 (whose cross-sections
have a rectangular shape respectively) are formed on the lower
portion of the side surface of the plug body 36. In addition, a
small projection 49 and a small receiving portion 50 positioned
below the small projection 49 (whose cross-sections have a
rectangular shape respectively) are formed on the inner surface of
the water-stopping member 46. For this reason, in a case where the
water-stopping member 46 is fitted on the plug body 36, since the
small projection 49 is fitted on the small concave portion 47 and
the small convex portion 48 is fitted on the small receiving
portion 50, positioning and stopping of the plug body 36 and the
water-stopping member 46 are performed.
[0044] Moreover, a lowering stopping portion 52 for a convex
portion is formed on the outside of an upper end 51 of the opening
portion of the plug body 36. When the lowering stopping portion 52
abuts on a joint end 53 between the inner container 5 and the outer
container 4, lowering of the plug body 36 more than necessary is
prevented. In a state in which the lid body 35 and the plug body 36
are mounted on the container, the upper end of the lowering
stopping portion 52 abuts on the top surface 34 of the lid body
35.
[0045] The water-stopping member 46 fitted on the plug body 36 is
brought into close contact with a seal portion step 54 formed on
the slightly lower side of the mouth portion 8 of the inner
container 5 and exhibits the water-stopping function. The diameter
of the seal portion step 54 is formed to be smaller than those of
the barrel portion and the mouth portion 8 of the inner container
5.
[0046] In a state in which the lid body 35 and the plug body 36 are
mounted on the container, a space 55 is formed between the lid body
35 and the plug body 36. Since the space 55 is filled with air, a
constant heat-insulating effect is exhibited.
[0047] Hereinafter, a method of producing the metallic vacuum
heat-insulating container 1 of the present embodiment will be
described.
[0048] First, the inner container 5 is inserted into the outer
container 4 from the opening portion 11 in the lower portion of the
outer container 4, and the mouth portion 8 of the inner container
is bonded to the mouth portion 12 of the outer container by
welding. Since the void between the inner container 5 and the outer
container 4 is made into the vacuum heat-insulating layer 15, the
mouth portion 8 of the inner container and the mouth portion 12 of
the outer container are welded over the entire circumference
without a gap. Further, since the inner container 5 and the outer
container 4 are welded such that the end surface of the mouth
portion 8 of the inner container and the end surface of the mouth
portion 12 of the outer container are aligned, the joint end 53
becomes flat without a difference in step.
[0049] Next, the outer bottom 3 to which the gas adsorber 23 is
welded is bonded to the opening portion 11 in the lower portion of
the outer container 5 by welding. The welding is performed over the
entire circumference by aligning the respective end surfaces
without a gap in the side surface lowermost portion 21 of the outer
container 5 and the outer bottom outermost portion 22 of the outer
bottom 3. In this manner, a container having a double wall
structure in which the inner container 5 and the outer container 4
are integrated is formed.
[0050] Next, air in the void between the inner container 5 and the
outer container 4 is discharged through the discharge hole 13
formed on the outer bottom 3 so as to be a vacuum, and the
discharge hole 13 is sealed with the vacuum-sealing material 14. In
this manner, the vacuum heat-insulating layer 15 is formed in the
void between the inner container 5 and the outer container 4.
[0051] Next, the bottom cover 7 is fitted on the outer container 4
from the lower side of the outer container 4 and bonded thereto by
welding. The bottom cover 7 is fitted such that the end portion 31
abuts on the first bent portion 32 and thus the bottom cover 7 is
positioned. The end portion 31 and the first bent portion 32 are
welded over the entire circumference and the tightly sealed space
27 is formed in a void between the outer container 4 and the bottom
cover 7.
[0052] Finally, the mouth portion 8 of the inner container is
closed by the plug body 36 and the lid body 35 is screwed to the
outer container 4, thereby completing the metallic vacuum
heat-insulating container 1.
[0053] As described above, in the metallic vacuum heat-insulating
container of the present embodiment, the metallic vacuum
heat-insulating container 1 has a double wall structure in which
the metallic bottomed cylindrical inner container 5 and the
metallic bottomed cylindrical outer container 4 are integrated in
respective mouth portions 8 and 12. The container 1 discharges air
in a void between the inner container 5 and the outer container 4
from the discharge hole 13 provided on the bottom surface 16 of the
outer container 4. The discharge hole 13 is sealed with the
vacuum-sealing material 14 to be made into the vacuum
heat-insulating layer 15, in which the outer container 4 is the
cylindrical outer cylinder 2 whose upper end and lower end are both
opened. the inner diameter of the mouth portion 12 of the outer
container which is an opening portion of the upper end is smaller
than that of a barrel portion 28. The disk-like outer bottom 3 is
be integrated with the lower end of the outer cylinder 2 by
welding. The stepped portion 29 whose diameter is smaller than the
diameter of the barrel portion 28 is provided on the side surface 6
on the lower side of the barrel portion 28 of the outer cylinder 2,
the opening portion 24 of the metallic bottomed cylindrical bottom
cover 7, which has a diameter substantially the same as the
diameter of the barrel portion 28, is allowed to abut on the
stepped portion 29, and the abutting portions are integrated by
welding.
[0054] Accordingly, since water does not infiltrate into the void
between the outer container 4 and the bottom cover 7 and the bottom
cover 7 is made of a metal, the vacuum-sealing material 14 can be
securely protected.
[0055] Further, because of integration by welding, the bottom cover
7 is not peeled off even in a high-temperature environment.
[0056] Further, productivity can be improved by welding the opening
portion 24 of the bottom cover 7 to the stepped portion 29 which is
hardly buckled because of the vacuum treatment.
[0057] Further, in the metallic vacuum heat-insulating container of
the present embodiment, since one or more reinforcing stepped
portions 26 are included on the bottom surface 25 of the bottom
cover 7, the void between the outer container 4 and the bottom
cover 7 is tightly sealed by welding. Also, it is possible to
prevent the bottom cover 7 from being swollen even when the inner
pressure of the tightly sealed space 27 is increased in a
high-temperature environment. Further, there is an effect of
preventing deformation due to an impact caused by a fall or the
like.
Second Embodiment
[0058] FIG. 7 illustrates a metallic vacuum heat-insulating
container of a second embodiment of the present invention. The
constituent elements which are the same as those of the first
embodiment are denoted by the same reference numerals and the
description thereof is not repeated.
[0059] In the present embodiment, a buffering material 56 is
disposed in the tightly sealed space 27 which is a void between the
outer container 4 and the bottom cover 7.
[0060] The buffering material 56 is a foamed molded body formed of
expanded polystyrene or expanded polypropylene and has a shape
substantially the same as the tightly sealed space 27 formed in a
state in which the bottom cover 7 is bonded to the outer container
4. Therefore, since the buffering material 56 is accommodated in
the tightly sealed space 27 without being floated, the buffering
material 56 is not required to be fixed by an adhesive or the
like.
[0061] The buffering material 56 prevents the vacuum-sealing
material 14 from being damaged when the bottom cover 7 directly
hits the vacuum-sealing material 14 in a case where the bottom
cover 7 of the metallic vacuum heat-insulating container 1 is
deformed in the inside thereof due to an impact caused by a fall or
the like.
[0062] In addition, since the buffering material 56 is disposed in
the tightly sealed space 27 formed by the outer container 4 and the
bottom cover 7 being bonded to each other by welding, water does
not reach the buffering material 56 through infiltration from the
outside. Therefore, corrosion of the buffering material 56 due to
water or growth of mold thereon does not occur.
Third Embodiment
[0063] FIG. 8 illustrates a metallic vacuum heat-insulating
container of a third embodiment of the present invention. The
constituent elements which are the same as those of the first
embodiment are denoted by the same reference numerals and the
description thereof is not repeated.
[0064] In the present embodiment, a magnet 57 is disposed in the
tightly sealed space 27 which is a void between the outer container
4 and the bottom cover 7.
[0065] The magnet 57 is a circular flat plate and is disposed in
the inside (in the tightly sealed space 27) of a surface 58 on
which the metallic vacuum heat-insulating container 1 is placed and
which is formed on the more outer peripheral side than the
reinforcing stepped portion 26 of the bottom cover 7. Further,
since the outer container 4 and the bottom cover 7 are bonded to
each other by welding in a state of the magnet 57 being disposed in
the tightly sealed space 27, water does not reach the magnet 57
through infiltration from the outside.
[0066] A permanent magnet, particularly, a neodymium magnet or a
ferrite magnet is used as the magnet 57, but since water does not
touch the magnet 57 as described above, a rustproof treatment is
not necessary. Further, since the magnet 57 is completely covered
by the bottom cover 7, an impact from the outside caused by a fall
or the like is reduced and the magnet 57 is hardly or not at all
damaged.
[0067] The thickness of the magnet 57 is formed to a degree as the
magnet is not in contact with the outer bottom 3 in a state in
which the outer container 4 and the bottom cover 7 are bonded to
each other.
[0068] A metal with magnetism (for example, SUS430) is used as a
material of the bottom cover 7 of the present embodiment, and since
the magnet 57 is stuck to the bottom cover 7 due to the magnetic
force, the magnet 57 is not required to be fixed. However, in a
case where a metal without magnetism (for example, SUS304) is used
as a material of the bottom cover 7, the magnet 57 is fixed to the
bottom cover 7 by brazing or an adhesive with high heat resistance.
Further, since the magnet 57 is water-tightly disposed in the
tightly sealed space 27, corrosion of the brazing or the adhesive
due to water does not occur.
[0069] As described above, in the metallic vacuum heat-insulating
container of the present embodiment, the magnet 57 is disposed in
the inside of the surface 58 on which the metallic vacuum
heat-insulating container is placed. Therefore, in a case where the
metallic vacuum heat-insulating container 1 is placed on a table
having magnetism, the magnet 57 is stuck to the table so that it is
possible to prevent the metallic vacuum heat-insulating container 1
from being easily collapsed. Further, in a case where the metallic
vacuum heat-insulating container 1 is placed on a table without
magnetism, since the magnet 57 is disposed on the bottom portion of
the metallic vacuum heat-insulating container 1, the gravity center
of the metallic vacuum heat-insulating container 1 is lowered down
due to the weight of the magnet 57 and the stability is increased
so that it is possible to prevent the metallic vacuum
heat-insulating container 1 from being easily collapsed. Therefore,
there is an effect of preventing the metallic vacuum
heat-insulating container 1 from being damaged because of a fall
from the table or the like and preventing a housed object from
spilling when the metallic vacuum heat-insulating container 1 is
turned down in a state in which the lid unit 9 is removed.
[0070] Further, in the present embodiment, the magnet 57 may have a
different shape, or multiple magnets may fill the space, but the
magnets are uniformly arranged in the lateral direction, the
vertical direction, and the oblique direction such that the
position of the gravity center of the metallic vacuum
heat-insulating container 1 does not move in the lateral direction,
the vertical direction, or the oblique direction.
[0071] Further, in the present embodiment, the buffering material
56 of the second embodiment may be provided. In this case, the
buffering material 56 is formed along the shape of the tightly
sealed space 27 in a state in which the magnet 57 is installed.
[0072] Furthermore, the present invention is not limited to the
present embodiment and various modified embodiments are possible
within the range not departing from the scope of the present
invention. For example, a two-component configuration in which the
barrel portion and the bottom portion in the inner container are
provided as separate components and then bonded by welding to be an
integrated component may be adopted. In addition, the capacity of
the container can be appropriately changed by changing the diameter
or the length of the container.
[0073] While preferred embodiments of the invention have been
described and illustrated above, it should be understood that these
are exemplary of the invention and are not to be considered as
limiting. Additions, omissions, substitutions, and other
modifications can be made without departing from the spirit or
scope of the present invention. Accordingly, the invention is not
to be considered as being limited by the foregoing description, and
is only limited by the scope of the appended claims.
* * * * *