U.S. patent application number 10/655837 was filed with the patent office on 2004-04-15 for heat-insulating container.
Invention is credited to Miura, Ikuo, Ohno, Takashi, Watanabe, Isao.
Application Number | 20040069789 10/655837 |
Document ID | / |
Family ID | 32063478 |
Filed Date | 2004-04-15 |
United States Patent
Application |
20040069789 |
Kind Code |
A1 |
Ohno, Takashi ; et
al. |
April 15, 2004 |
Heat-insulating container
Abstract
A heat insulating container is provided with an outer vessel 2
and an inner vessel 1 arranged in the outer vessel 2 with a gap 3,
at least a bag 4 arranged in the gap 3, and a reinforcement member
10 with a rigidity higher than the composition material of the bag
4, arranged on at least one peripheral side of the bag 4. The
reinforcement member 10 extends along the edge portion of the bag
4. The bag 4 is formed into a rectangular shape, and the
reinforcement member 10 is arranged along at least two opposite
sides of the bag 4. As a protrusion of one of the inner or outer
vessels engages with the cavity or the protrusion of the
reinforcement member 10 of the bag 4, the bags 4 can be easily
inserted into the gap 3.
Inventors: |
Ohno, Takashi; (Tokyo,
JP) ; Miura, Ikuo; (Tokyo, JP) ; Watanabe,
Isao; (Tokyo, JP) |
Correspondence
Address: |
J.C. Patents
Suite 250
4 Venture
Irvine
CA
92618
US
|
Family ID: |
32063478 |
Appl. No.: |
10/655837 |
Filed: |
September 4, 2003 |
Current U.S.
Class: |
220/592.2 |
Current CPC
Class: |
F25D 2201/10 20130101;
A47J 41/022 20130101 |
Class at
Publication: |
220/592.2 |
International
Class: |
B65D 081/38 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 12, 2002 |
JP |
2002-266786 |
Claims
What is claimed is:
1. A heat insulating container comprising: an inner vessel and an
outer vessel, wherein the inner vessel is arranged in the outer
vessel with a gap therebetween; at least a bag, arranged in the
gap, wherein the gap is filled with a gas whose heat-conductivity
is lower than that of air; and a reinforcement member, made of a
material whose rigidity is higher than that of a composition
material of the bag, arranged on at least one peripheral side of
the bag.
2. A heat-insulating container according to claim 1, wherein the
reinforcement member is arranged at two sides of the bag.
3. A heat-insulating container according to claim 1, further
comprising: a first protrusion or a first cavity, formed in at
least one of the inner vessel and/or the outer vessel; and a second
cavity or a second protrusion corresponding to the first protrusion
or the first cavity of the inner or outer vessels, formed on the
reinforcement member, and wherein as the first protrusion or the
first cavity of the inner or outer vessels engages with the second
cavity or the second protrusion of the reinforcement member, the
bag can be easily inserted into the gap.
4. A heat-insulating container according to claim 2, further
comprising: a first protrusion or a first cavity, formed in at
least one of the inner vessel and/or the outer vessel; and a second
cavity or a second protrusion corresponding to the first protrusion
or the first cavity of the inner or outer vessels, formed on the
reinforcement member, and wherein as the first protrusion or the
first cavity of the inner or outer vessels engages with the second
cavity or the second protrusion of the reinforcement member, the
bag can be easily inserted into the gap.
5. A heat-insulating container according to claim 1, wherein the
inner vessel and the outer vessel are formed into polygonal shapes,
and each of the bags is inserted into the gap corresponding to at
least two adjacent sides of the polygons, and wherein further
comprising: a cavity or a protrusion, formed on each of the
reinforcement member of each bag, wherein as the protrusion or the
cavity of one of the reinforcement member of one the bags engages
with the corresponding cavity or the corresponding protrusion of
the reinforcement member of the other bag, the bags can be easily
inserted into the gap.
6. A heat-insulating container according to claim 2, wherein the
inner vessel and the outer vessel are formed into polygonal shapes,
and each of the bags is inserted into the gap corresponding to at
least two adjacent sides of the polygons, and wherein further
comprising: a cavity or a protrusion, formed on each of the
reinforcement member of each bag, wherein as the protrusion or the
cavity of one of the reinforcement member of one the bags engages
with the corresponding cavity or the corresponding protrusion of
the reinforcement member of the other bag, the bags can be easily
inserted into the gap.
7. A heat-insulating container according to claim 3, wherein the
inner vessel and the outer vessel are formed into polygonal shapes,
and each of the bags is inserted into the gap corresponding to at
least two adjacent sides of the polygons, and wherein further
comprising: a cavity or a protrusion, formed on each of the
reinforcement member of each bag, wherein as the protrusion or the
cavity of one of the reinforcement member of one the bags engages
with the corresponding cavity or the corresponding protrusion of
the reinforcement member of the other bag, the bags can be easily
inserted into the gap.
8. A heat-insulating container according to claim 4, wherein the
inner vessel and the outer vessel are formed into polygonal shapes,
and each of the bags is inserted into the gap corresponding to at
least two adjacent sides of the polygons, and wherein further
comprising: a cavity or a protrusion, formed on each of the
reinforcement member of each bag, wherein as the protrusion or the
cavity of one of the reinforcement member of one the bags engages
with the corresponding cavity or the corresponding protrusion of
the reinforcement member of the other bag, the bags can be easily
inserted into the gap.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the priority benefit of Japanese
application serial no. 2002-266786, filed on Sep. 12, 2002.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention generally relates to a heat-insulating
container applied in a freezer/refrigerator, cooler box, vacuum
bottle, a heat-insulation lunch box or the like. More specifically,
relates to a double-walled heat-insulating container comprising an
inner vessel and an outer vessel, wherein a heat-insulating layer
is formed between the inner vessel and the outer vessel.
[0004] 2. Description of the Related Art
[0005] A heat-insulating container such as a cooler box has an
outer vessel and an inner vessel made of a synthetic resin. In the
double-walled container, a gap exists between the inner vessel and
the outer vessel. A bag having a barrier property is filled with a
gas (hereinafter, low heat-conductivity gas) whose heat
conductivity is lower than air, such as krypton, xenon, argon, or a
mixing gas thereof, and the bag is inserted into the gap (referring
to Japan Patent No. 2989447).
[0006] Although the bag of the conventional heat-insulating
container can be filled with a predetermined amount of low
heat-conductivity gas, the thickness of the central portion of the
bag is larger than that of the edge portion. When inserting the bag
into the gap between the inner vessel and the outer vessel, the
central portion of the bag rubs against the sidewalls of the inner
vessel and the outer vessel. The bag may not be properly inserted
into the gap up to the depth end of the gap. If the bag filled with
the low heat-conductivity gas is not properly inserted into the
gap, a partial heat-insulating layer cannot be formed between the
inner and the outer vessels of the heat-insulating container, and
the heat-insulating performance will be adversely affected.
[0007] When the inner and outer vessels are integrally jointed by
welding, it is difficult to maintain a uniform gap width. In a case
when the bag is inserted into a gap that is wider than a
predetermined value, some unwanted space is created between the
inner and outer vessels, and the part with the larger gap may cause
the heat-insulating performance become low. On the other hand, in a
case when the bag is inserted into a gap narrower than a
predetermined value, this may cause the problems such as
application of excessive force resulting in wrinkling and bending
of the bag that would otherwise generate pinholes in the bag can be
avoided. Thus, the low heat-conductivity gas leaks as time goes by,
and the heat-insulating performance is lowered gradually.
[0008] Particularly, if there exists a thickness difference between
the central portion and the edge portion of the bag, the
heat-insulating container becomes a polygonal shape, for example, a
box of rectangular solid shape. The edge portion that is thinner
than the central portion of the bag is arranged at the corner of
the polygonal solid heat-insulating container. No heat-insulating
member can be arranged at the corner, and the bag is not in contact
with the inner wall of the heat-insulating container. Then, an air
layer is created between the bag and the inner wall at the corner
of the heat-insulating container, and the heat-insulating
performance is lowered which is not preferable.
[0009] In order to prevent the lowering of the heat-insulating
performance, the Japanese Patent No. 2989447 discloses arranging a
heat-insulating material at the corner of the heat-insulating
container. However, the shape of the heat-insulating material is
fixed such that when an insulating material in addition to the bag
are inserted into the gap of the heat-insulating container, an
excessive force is exerted on the bag. Thus, the bag is easily
damaged.
SUMMARY OF THE INVENTION
[0010] The present invention is provided to solve the
aforementioned problems and it is an object of the present
invention to provide a heat-insulating container featuring a long
and stable heat-insulating performance without partially
deteriorating heat-insulating performance.
[0011] The aforementioned problems are solved by providing a heat
insulating container comprising: an inner vessel and an outer
vessel, wherein the inner vessel is arranged in the outer vessel
with a gap; at least a bag, arranged in the gap, wherein the gap is
filled with a gas whose heat-conductivity is lower than that of
air; and a reinforcement member, made of a material whose rigidity
is higher than that of a composition material of the bag, is
arranged on at least one peripheral side of the bag.
[0012] According to one aspect of the present invention, the
reinforcement member is arranged at two sides of the bag.
[0013] According to another aspect of the present invention, a
protrusion or a cavity is formed in at least one of the inner
vessel and the outer vessel, and a cavity or a protrusion
corresponding to the protrusion or the cavity of the inner or outer
vessels is formed on the reinforcement member. As the protrusion or
the cavity of one of the inner or outer vessels engages with the
corresponding cavity or the corresponding protrusion of the
reinforcement member, the bag can be easily inserted into the
gap.
[0014] According to still another aspect of the present invention,
the inner vessel and the outer vessel are formed into polygonal
shapes. Each of the bags is inserted into the gap corresponding to
at least two adjacent sides of the polygons, and a cavity or a
protrusion is formed on the reinforcement member arranged onto one
of the bags, and a protrusion or a cavity corresponding to the
cavity or the protrusion, is formed on the other reinforcement
member arranged onto the other bag. As the cavity or the protrusion
of one of the reinforcement member of one of the bags engages with
the corresponding protrusion or the cavity of the reinforcement
member of the other bag, the bags can be easily inserted into the
gap.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] While the specification concludes with claims particularly
pointing out and distinctly claiming the subject matter which is
regarded as the invention, the objects and features of the
invention and further objects, features and advantages thereof will
be better understood from the following description taken in
connection with the following accompanying drawings.
[0016] FIG. 1 is a perspective view showing heat-insulating
container according to one embodiment of the present invention.
[0017] FIG. 2 is a perspective view showing the first example of
the reinforcement structure (formed with reinforcement members) of
the bag.
[0018] FIG. 3 is a perspective view showing the structure of the
reinforcement member.
[0019] FIG. 4 is a partial plane view of the reinforcement member
of the first example.
[0020] FIG. 5 is a partial plane view of the reinforcement member
of the second example.
[0021] FIG. 6 is a perspective view showing the second example of
the reinforcement structure (formed with reinforcement members) of
the bag.
[0022] FIG. 7 is a perspective view showing the third example of
the reinforcement structure (formed with reinforcement members) of
the bag.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0023] The present invention will be described in detail as
follows.
[0024] A heat-insulating container according to one embodiment of
the present invention is illustrated with reference to FIGS. 1
through 5.
[0025] FIG. 1 is a perspective view showing a heat-insulating
container according to one embodiment of the present invention.
[0026] In this embodiment, the heat-insulating container is a
double-walled container in which an inner vessel 1 is arranged in
the outer vessel 2 with a gap 3 therebetween, and a bag 4 is
arranged in the gap 3.
[0027] The inner vessel 1 is made of a synthetic resin, such as ABS
resin, and a metal such as stainless steel, and is shaped into a
rectangular solid structure having an upper opening. The outer
vessel 2 is made of a synthetic resin, such as ABS resin, and a
metal such as stainless steel, and is shaped into a rectangular
solid structure having an upper opening.
[0028] In this embodiment, a low heat-conductivity gas whose
heat-conductivity is lower than air is filled in the
heat-insulating container. The bag 4 is arranged over the gap
between the whole surfaces of a sidewall 1a of the inner vessel 1
and a sidewall 2a of the outer vessel 2 facing to the inner vessel
1. In other words, four bags 4 are respectively arranged in the gap
3 between the four sidewalls 1a and four sidewalls 2a.
[0029] A sealing member (not shown) is formed on an opening surface
of the gap formed between the inner vessel 1 and the outer vessel
2. It is preferable to arrange the bag filled with a low
heat-conductivity gas in the gap at the bottom part of the
heat-insulating container.
[0030] A cap capable of opening or closing the upper opening of the
heat-insulating container can be properly arranged in the present
invention. It is preferred that the cap comprising an upper plate
and a lower plate, wherein a bag filled with a low
heat-conductivity gas is arranged in the gap between the two plates
or wherein a foaming heat-insulating material is arranged in the
gap.
[0031] The bag 4 with a rectangular shape is formed by heat-sealing
plates (made of soft material having a gas barrier property) at
three sides of its periphery, such as a five-layer structured sheet
made of polypropylene/nylon/polyethylene terephthalate
/aluminum/polyethylene wherein three peripheral sides are
heat-sealed to form into a bag shape.
[0032] Among the five layers, the polypropylene layer maintains the
strength of the bag 4; the nylon layer, polyethylene terephthalate
and aluminum layers maintain the gas barrier property; and the
polyethylene layer seals the heat.
[0033] FIG. 2 is a perspective view showing the first example of
the reinforcement structure of the bag 4.
[0034] A reinforcement member 10 whose rigidity is higher than the
composition material of the bag 4 is arranged on at least a
peripheral part of the bag 4.
[0035] In this example, the reinforcement members 10 extend along
two sides among the heat-sealed portions 4a forming three
peripheral sides of the bag 4. The reinforcement members 10 are
arranged at two sides of the bag 4, i.e. two sides that oppose each
other among the heat-sealed portions 4a. Moreover, the
reinforcement members 10 are arranged from the opening portion 5 of
the heat-insulating container towards the bottom portion 6.
Furthermore, the reinforcement member 10 is comprised of plates 11
with a rectangular shape wherein a hinge 11a is formed along the
length of the reinforcement member 10, such that the reinforcement
member 10 can be folded relative to the hinge 11a.
[0036] Cavities 10a formed into a continuous groove shape extend
over the length of the reinforcement member 10, as shown in FIG. 3.
A crossing portion 10c is formed in the cavity 10a at a
predetermined position. FIG. 3 shows an example of the
reinforcement member 10 wherein cavities 10a are formed. However,
it is also possible to intermittently form a protrusion and to
arrange a concave crossing portion along the length of the
reinforcement member 10.
[0037] It is preferred that the reinforcement member 10 is made of
a synthetic resin or a foaming material of a synthetic resin with a
low heat-conductivity and a high mechanical strength, such as
polypropylene and polyethylene. Because the reinforcement member 10
is made of the synthetic resin or the foaming material of which,
the reinforcement member 10 itself has a heat-insulating
property.
[0038] FIG. 4 is a partial plane view of the reinforcement member
of the first example.
[0039] In this example, the bag 4 fixed by the reinforcement member
10 and the other bag 4 fixed by the reinforcement member 12 are
respectively arranged in the gap 3 corresponding to the two
adjacent surfaces among the surfaces constructing the inner vessel
1 and the outer vessel 2, as shown in FIG. 4.
[0040] A protrusion 2d is formed on an inner surface of the
sidewall 2a at a place nearby the corner 2c of the outer vessel 2.
The protrusion 2d extends from the opening portion 5 of the
heat-insulating container towards the bottom portion 6. A cavity
10a provided at one side of the reinforcement member 10 is engaged
with the protrusion 2d. Similarly, a protrusion 2e is formed on an
inner surface of the sidewall 2b adjacent to the sidewall 2a. The
protrusion 2e extends from the opening portion 5 of the
heat-insulating container towards the bottom portion 6. A cavity
12a of the reinforcement member 12 is engaged with the protrusion
2e. The protrusions 2d and 2e are not necessarily formed in the
same length as the cavities 10a and 12a, and can be intermittently
formed on the inner surfaces of the sidewalls 2a and 2b to
partially engage with the cavities 10a and 12a.
[0041] At the corner of the gap 3, one of the two cavities 10a in
two surfaces of the reinforcement member 10 which is not engaged
with the protrusion 2d is for engaging with the protrusion 12b of
the reinforcement member 12.
[0042] FIG. 5 is a partial plane view of the reinforcement member
of the second example.
[0043] In this example, the bag 4 fixed by the reinforcement member
13 and the other bag 4 fixed by the reinforcement member 14 are
respectively arranged in the gap 3 corresponding to the two
adjacent surfaces among the surfaces constructing the inner vessel
1 and the outer vessel 2, as shown in FIG. 5.
[0044] A protrusion 2f is formed on an inner surface of the
sidewall 2a at a place nearby the corner 2c of the outer vessel 2.
The protrusion 2f extends from the opening portion of the
heat-insulating container towards the bottom portion 6. A cavity
13a provided at one side of the reinforcement member 13 is engaged
with the protrusion 2f. The protrusions 2f is not necessarily
formed in the same length as the cavity 13a, and can be
intermittently formed on the inner surfaces of the sidewalls 2a to
partially engage with the cavity 13a.
[0045] At the corner of the gap 3, one of the two cavities 13a in
two surfaces of the reinforcement member 13 which is not engaged
with the protrusion 2f is for engaging with the reinforcement
member 14.
[0046] FIGS. 4 and 5 show examples that the protrusion for engaging
with the cavity of the reinforcement member is formed on the inner
surface of the sidewalls 2a, 2b. However, it is also possible to
form a cavity for engaging with the protrusion of the reinforcement
member on the inner surfaces of the sidewalls 2a, 2b from the
opening portion 5 of the heat-insulating container towards the
bottom portion 6.
[0047] Moreover, in the heat-insulating container according to the
embodiment of the present invention, at a place nearby the corner
1b at the outer surface of the sidewall 1a, a cavity engaged with
the protrusion of the reinforcement member or a protrusion engaged
with the cavity of the reinforcement member can be formed from the
opening portion 5 of the heat-insulating container towards the
bottom portion 6.
[0048] Accordingly, a cavity or a protrusion is formed on at least
one of the inner vessel 1 and outer vessel 2, and a protrusion or a
cavity that corresponds to the cavity or the protrusion on the
inner vessel 1 or the outer vessel 2 is formed on the reinforcement
member. By engaging the protrusion at one side with the cavity at
the other side, the bag 4 can be fixed by the reinforcement member.
When inserting the bag 4 into the gap 3, the bag 4 can be guided by
the protrusion or cavity facilitating the insertion into the gap 3
towards the bottom portion 6 through the opening portion 5 of the
heat-insulating container, and properly arrange the bag 4 in a
predetermined position in the gap 3 in a direction perpendicular to
the bottom portion 6.
[0049] Because the crossing portion is arranged in the cavity of
the reinforcement member, when inserting the bag 4 into the gap 3,
the bag 4 is caught by the cavity or protrusion arranged in the
inner vessel 1 or the outer vessel 2, and therefore the bag 4 can
be properly arranged and fixed in a predetermined position in the
gap 3.
[0050] In a case when the protrusion is intermittently arranged on
the inner vessel 1, outer vessel 2 or the reinforcement member,
because the contact area between the reinforcement member and the
inner vessel 1 or the outer vessel 2 is small, the heat-dissipation
due to heat conduction from the inner vessel 1 towards the outer
vessel 2 through the reinforcement member can be lowered.
[0051] By arranging the bag 4 fixed by two reinforcement members to
engage with the reinforcement members at the corner of the gap 3
corresponding to the two adjacent surfaces, the bag 4 can be
properly positioned in the gap 3. Additionally, because the
reinforcement member is made of the foaming material of the
synthetic resin with a low heat-conductivity, the heat-insulating
performance at the corner of the gap 3 cannot be lowered.
[0052] A method for manufacturing a heat-insulating container
according to one embodiment of the present invention will be
describe with reference to FIGS. 1 and 2.
[0053] The Manufacture of the Bag
[0054] First, a sheet made of a soft material with a gas barrier
property is cut into predetermined dimensions and then folded. The
folded sheet is heat-sealed except the non-sealing edge portion to
form a half-finished body of the bag. Secondly, a tube is inserted
into the non-sealed portion. The half-finished body of the bag is
filled with a low heat-conductivity gas through the tube. After
filling enough low heat-conductivity gas, the non-sealed portion is
then heat-sealed to complete the bag 4.
[0055] The Assembly of the Heat-Insulating Container
[0056] First, a plurality of through holes 4b is formed in the bag
4 in positions at two sides opposite to each other among the
heat-sealed portions 4a. Secondly, after fitting the protrusions
11b of the plates 11 into the through holes 4b of the heat-sealed
portions 4a, the plates 11 are folded relative to the hinge 11a.
Two reinforcement members 10 respectively sandwich two opposite
sides among the heat-sealed portions 4a, such that the
reinforcement members 10 are fixed onto the bag 4. When the plate
11 is folded, the protrusions 11b are fit in the receiving portion
11c formed in the opposite surface. Therefore, two surfaces of the
heat-sealed portions 4a are tightly connected with the plates 11,
and the reinforcement members 10 are fixed onto the bag 4.
Regarding the other fixing method, the plates 11 and the
heat-sealed portions 4a can be fixed to each other by using an
adhesive or a tape. Secondly, the bag 4 fixed by the reinforcement
member 10 is inserted into the gap 3 towards the bottom portion 6
through the opening portion 5, such that a cavity or protrusion
formed on the reinforcement member along the length, engages with a
protrusion or cavity formed in the sidewall 1a or sidewall 2a.
Similarly, the other bag 4 fixed by the other reinforcement member
10 is inserted into the neighboring portion of the gap 3. At the
corner of the gap 3, a cavity or protrusion in one of the
reinforcement members 10 engages with a protrusion or a cavity of
the other reinforcement members 10. Accordingly, a heat-insulating
container wherein four bags are arranged in the gap 3 corresponding
to the four sidewalls 1a and 2a is obtained.
[0057] As a result, in this heat-insulating container, by arranging
the reinforcement members 10 at two opposite sides among the
heat-sealed portions 4a of the bag 4, the problems such as the
wrinkling or bending of the bag 4 can be prevented. Thus, the bag 4
can be inserted up to the depth end of the gap 3.
[0058] Moreover, because the protrusions 11b of the plates 11 fit
in the through holes 4b of the heat-sealed portions 4a, the bag 4
can be positioned and fixed at a correct position relative to the
reinforcement members 10.
[0059] In the heat-insulating container according to the embodiment
of the present invention, each of the bags 4 is respectively
inserted into the gap 3 corresponding to the sidewalls 1a and 2a to
form a single heat-insulating layer. However, it is also possible
to insert two or more bags 4 by putting one upon another into the
gap 3 to form a plurality of heat-insulating layers. Accordingly,
even if the gap is in the same dimension, the heat-insulating
performance can be improved due to the laminated structure.
Moreover, it is also possible to use one reinforcement member 10 to
laminate and fix two or more bags 4.
[0060] FIG. 6 is a perspective view showing the second example of a
reinforcement structure (formed with reinforcement members) of the
bag 4.
[0061] In this example, the reinforcement member 20 comprises
reinforcement plates 21 and 22 that are formed into C-shapes by
using base portions 21a, 22a and extending portions 21b, 22b that
vertically extend from two ends of the base portions 21a, 22a. The
base portions 21a and 22a are connected to each other by a
hinge-connection. In this example, the reinforcement member 20 is
fixed onto the heat-sealed portions 4a corresponding to three sides
of the bag 4.
[0062] In this example, a method for fixing the reinforcement
members 20 onto the bag 4 is described as follows.
[0063] After fitting the protrusions 21c of the reinforcement plate
21 into the through holes 4b formed in the heat-sealed portions 4a
of the bag 4, the reinforcement member 20 is folded relative to the
hinge-connection portion. The reinforcement plates 21, 22
respectively sandwich the heat-sealed portions 4a, such that the
reinforcement member 20 is fixed onto the bag 4. When the
reinforcement member 20 is folded, the protrusions 21c are fit in
the receiving portions 22c formed in the surface of the
reinforcement plate 22 opposite to the reinforcement plate 21.
Therefore, heat-sealed portions 4a are tightly connected with the
reinforcement plates 21 and 22, and the reinforcement member 20 is
fixed onto the bag 4. Moreover, because the protrusions 21c of the
reinforcement plate 21 fit in the through holes 4b of the
heat-sealed portions 4a, the bag 4 can be positioned and fixed at a
correct position relative to the reinforcement member 20. Regarding
to other fixing method, the reinforcement plates 21, 22 and the
heat-sealed portions 4a can be fixed onto the bag 4 by using an
adhesive or a tape.
[0064] In this example, the reinforcement structure is different
from that of the first example, such that the reinforcement member
20 is fixed onto the heat-sealed portions 4a (edge portion)
corresponding to three sides of the bag 4, and the bag 4 is much
easier to be inserted into the gap 3 (up to the depth end of the
gap 3). Because the reinforcement member 20 is fixed onto the
heat-sealed portions 4a corresponding to the three sides of the bag
4, it is hard to apply excessive force on the bag, so that
wrinkling and bending of the bag during insertion of the bag 4 into
the gap 3 do not occur.
[0065] FIG. 7 is a perspective view showing the third example of
the reinforcement structure (formed with reinforcement members) of
the bag 4.
[0066] In this example, the reinforcement member 30 comprises
reinforcement plates 31 and 32 formed into C-shapes similar to the
reinforcement members 21, 22, wherein a grid portion 32d formed
into a grid-shape with roughly the same dimensions in swelling as
the gap is formed thereon, and base portions 31a, 32a are
hinged-connected with each other. In this example, the
reinforcement member 30 is fixed onto the heat-sealed portions 4a
corresponding to the three sides of the bag 4.
[0067] Regarding this example, the method of fixing the
reinforcement member 30 onto the bag 4 is described as follows.
[0068] After fitting the protrusions 31c formed on the
reinforcement plate 31 into the through holes 4b formed in the
heat-sealed portions 4a of the bag 4, the reinforcement member 30
is folded relative to the hinge connection portion. The
reinforcement plates 31, 32 respectively sandwich the heat-sealed
portions 4a, such that the reinforcement member 30 is fixed onto
the bag 4. When the reinforcement member 30 is folded, the
protrusions 31 are fit in the receiving portions 32c formed in the
surface of the reinforcement plate 32 opposite to the reinforcement
plate 31. Therefore, heat-sealed portions 4a are tightly connected
with the reinforcement plates 31 and 32, and the bag 4 is fixed by
the reinforcement member 30. Moreover, because the protrusions 31c
of the reinforcement plate 31 fit in the through holes 4b of the
heat-sealed portions 4a, the bag 4 can be positioned and fixed at a
correct position relative to the reinforcement member 30. The
reinforcement plates 31, 32 and the heat-sealed portions 4a are
preferably fixed onto the bag 4 by using an adhesive or a tape.
[0069] In this example, the reinforcement structure is different
from that of the first example, such that the reinforcement member
30 is fixed onto the heat-sealed portions 4a (edge portion)
corresponding to the three sides of the bag 4, and the bag 4 are
much easier to be inserted into the gap 3 (up to the depth end of
the gap 3). Because the reinforcement member 30 is fixed onto the
heat-sealed portions 4a corresponding to the three sides of the bag
4, it is hard to apply excessive force on the bag, so that
wrinkling and bending of the bag during the insertion of the bag 4
into the gap 3 do not occur.
[0070] Furthermore, after the bag 4 is filled with a predetermined
amount of low heat-conductivity gas, the thickness of the central
portion of bag 4 becomes larger than that of the edge portion of
the bag 4. In the reinforcement structure of the bag 4 according to
this example, by pressing the central portion of the bag 4 by the
grid-shaped grid portion 32d of the reinforcement plate 32, the
thickness of the bag 4 become roughly uniform. As a result, the bag
4 can be easily inserted into the gap 3, and the partially lowered
heat-insulating performance in the gap 3 due to the partially
uneven thickness of the bag 4 can be eliminated.
[0071] In the heat-insulating container according to the embodiment
of the present invention, the heat-insulating container is a
rectangular solid structure. However, the shape of the
heat-insulating container is not limited to this particular shape.
So long as the bag fixed by the reinforcement member can be
inserted into the gap of the heat-insulating container, the
heat-insulating container can be formed in any shape, for example,
can be a cylindrical shape.
[0072] Practical Embodiment
[0073] The effects of the present invention can be understood with
reference to the following practical embodiment referring to FIG.
1.
[0074] A rectangular solid shaped double-walled container is
manufactured by using an inner vessel 1 whose thickness is 2.0 mm
and an outer vessel 2 whose thickness is 2.0 mm. The outer
dimensions (the dimensions of the outline of the outer vessel 2) of
the double-walled container are 380 mm Width.times.380 mm
Length.times.200 mm Height; the dimensions of the outline of the
inner vessel 1 are 360 mm Width.times.360 mm Length.times.360 mm
Height. The width of the gap 3 is 10 mm, and the volume of the
inner vessel 1 is about 23 liter.
[0075] A cap (not shown) made of a synthetic resin in which a 20
mm-thickness foaming material is packed is installed on the upper
surface (opening portion) of the double-walled container by screws,
such that the cap can be opened or closed by using screws.
[0076] The gap 3 is filled with a predetermined amount of low
heat-conductivity gas, and the bags 4 fixed by the reinforcement
member 10 are inserted into the gap 3 to obtain the heat-insulating
container.
[0077] Comparison Example
[0078] A heat-insulating material made of foaming styrene is
inserted into the gap 3 of the double-walled container of the
comparison example whose double-walled structure is manufactured in
the same shape as the practical embodiment to obtain the
heat-insulating container of the comparison example.
[0079] The heat-insulating containers of the practical embodiment
and the comparison example are filled with hot water of 95.degree.
C., and the caps are closed. After the heat-insulating containers
are sealed, the two heat-insulating containers are placed in an
environment of 35.degree. C.
[0080] After about six hours, the water temperature are checked
out, it is found that in the heat-insulating container of the
practical embodiment the water temperature is about 87.degree. C.,
and the water temperature in the heat-insulating container of the
comparison example is about 82.degree. C.
[0081] As a result, the heat-insulating container of the practical
embodiment can be recognized as having a very good heat-insulating
performance.
[0082] As described above, in the heat-insulating container of the
present invention, because the bags that are filled with a low
heat-conductivity gas are fixed by the reinforcement member made of
a foaming material, are inserted into the gap of the
heat-insulating container, and therefore the bags can be properly
inserted into the gap (up to the depth end of the gap). Moreover,
during the insertion of the bag into the gap, there is no problem
such as applying excessive force on bags, so that wrinkling and
bending of the bags, creating pinholes in the bags resulting in
leaking the low heat-conductivity gas do not occur.
[0083] Accordingly, a cavity or a protrusion is formed on at least
one of the inner vessel 1 and the outer vessel 2, and a protrusion
or a cavity that corresponds to the cavity or the protrusion on the
inner vessel 1 or the outer vessel 2 is formed on the reinforcement
member. By engaging the protrusion at one side with the cavity at
the other side, the bag 4 can be fixed by the reinforcement member.
When inserting the bags 4 into the gap 3, the bags 4 can be guided
by the protrusion or cavity to insert into the gap 3 towards the
bottom portion 6 through the opening portion 5 of the
heat-insulating container, and to be properly arranged parallel to
each other in predetermined positions in the gap 3.
[0084] By arranging the two bags 4 to engage with the reinforcement
members at the corner of the gap 3 corresponding to the two
adjacent surfaces of the heat-insulating container, the bags 4 can
be properly positioned in the gap 3. Additionally, because the
reinforcement members are made of the foaming material of a
synthetic resin with a low heat-conductivity, the heat-insulating
performance at the corner of the gap 3 will not be lowered.
[0085] According to above aspects, the heat-insulating container of
the present invention has a heat-insulating effect for a long
duration and stable heat-insulating performance without partially
deteriorating heat-insulating performance.
[0086] While the present invention has been described with
preferred embodiments, this description is not intended to limit
the present invention. Various modifications of the embodiment will
be apparent to those skilled in the art. It is therefore
contemplated that the appended claims will cover any such
modifications or embodiments as fall within the true scope of the
invention.
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