U.S. patent application number 14/845689 was filed with the patent office on 2016-03-10 for bag equipped with a gas channel and a method and apparatus for packaging such a bag.
This patent application is currently assigned to TOYO JIDOKI CO., LTD.. The applicant listed for this patent is Toyo Jidoki Co., Ltd.. Invention is credited to Yasuyuki Honda.
Application Number | 20160068289 14/845689 |
Document ID | / |
Family ID | 54064125 |
Filed Date | 2016-03-10 |
United States Patent
Application |
20160068289 |
Kind Code |
A1 |
Honda; Yasuyuki |
March 10, 2016 |
BAG EQUIPPED WITH A GAS CHANNEL AND A METHOD AND APPARATUS FOR
PACKAGING SUCH A BAG
Abstract
A method and apparatus for packaging a bag (1) in which a gas
channel (5) where the laminated films constituting the front and
back faces of the bag are not fused is formed inside a sealed part
(2) of the side edge, with the lower end of the gas channel opening
(through a communicating portion (5b)) into the bag, and a gas
inlet (5a) that allows the gas channel to communicate with the
outside of the bag being formed at the upper end of the gas
channel. After the bag has been filled with its filling material, a
pressurized inert gas is blown from the gas inlet into the gas
channel and then through the gas channel into the bag, thus
replacing the air inside the bag with the inert gas. After this gas
replacement, the gas inlet is sealed, and the bag mouth is also
sealed.
Inventors: |
Honda; Yasuyuki;
(Iwakuni-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Toyo Jidoki Co., Ltd. |
Tokyo |
|
JP |
|
|
Assignee: |
TOYO JIDOKI CO., LTD.
Tokyo
JP
|
Family ID: |
54064125 |
Appl. No.: |
14/845689 |
Filed: |
September 4, 2015 |
Current U.S.
Class: |
53/434 ; 383/109;
53/512 |
Current CPC
Class: |
B29C 66/1122 20130101;
B29C 66/21 20130101; B65D 81/2084 20130101; B29C 65/18 20130101;
B29C 66/849 20130101; B65D 29/02 20130101; B29C 65/08 20130101;
B29C 65/72 20130101; B29C 66/3452 20130101; B65B 31/048 20130101;
B29C 66/0342 20130101; B65B 43/30 20130101; B29C 66/723 20130101;
B65B 1/06 20130101; B29C 66/81811 20130101; B29C 66/83221 20130101;
B65B 43/44 20130101; B29L 2031/7128 20130101; B29C 66/232 20130101;
B65D 33/22 20130101; B29C 66/43121 20130101; B29C 66/8242 20130101;
B29C 65/7841 20130101; B65B 7/02 20130101; B65B 51/225 20130101;
B65D 33/16 20130101; B29C 65/7882 20130101 |
International
Class: |
B65B 31/04 20060101
B65B031/04; B65B 43/30 20060101 B65B043/30; B65D 33/22 20060101
B65D033/22; B65D 30/08 20060101 B65D030/08; B65D 33/16 20060101
B65D033/16; B65B 7/02 20060101 B65B007/02; B65B 51/22 20060101
B65B051/22 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 5, 2014 |
JP |
2014-181718 |
Claims
1. A bag equipped with a gas channel, comprising: a sealed part
provided in a bottom edge and both side edges of a bag, the sealed
part being where laminated films that constitute front and back
faces of the bag are sealed, a gas channel where the laminated
films that constitute the front and back faces of the bag are not
fused, the gas channel being formed in the sealed part, and a part
of the gas channel opening into the bag, and a gas inlet formed in
one or both of laminated films constituting front and back faces of
the gas channel, the gas inlet allowing the gas channel to
communicate with outside of the bag.
2. The bag equipped with a gas channel according to claim 1,
wherein the gas channel is formed in the sealed part of a side edge
or is formed continuously in the sealed part of the side edge and
bottom edge, and the gas inlet is formed at an upper end of the gas
channel.
3. The bag equipped with a gas channel according to claim 2,
wherein the gas channel is formed in the sealed part of the side
edge, and a lower part of the gas channel opens into the bag.
4. The bag equipped with a gas channel according to any of claims 1
to 3, wherein the bag is a finished bag in which a bag is filled
with a filling material, air inside of the bag is replaced with an
inert gas, and a bag mouth at a top edge of the bag and the gas
inlet are sealed.
5. The bag equipped with a gas channel according to claim 4,
wherein a sealed part that continues intermittently along the bag
mouth is formed near the sealed mouth of the bag.
6. A bag packaging method, in which a pair of bag conveyance
grippers clamp side edges of a bag to hang down the bag while
conveying the bag along a specific conveyance path, and packaging
steps comprising opening up of a bag mouth, filling of the bag with
a filling material, replacing of air inside the bag with an inert
gas, and sealing of the bag mouth are successively carried out
during conveyance of the bag, wherein the bag is comprised of: a
sealed part provided in a bottom edge and both side edges of the
bag in which laminated films that constitute front and back faces
of the bag are sealed, a gas channel where the laminated films that
constitute the front and back faces of the bag are not fused, the
gas channel being formed in the sealed part, and a part of the gas
channel opening into the bag, and a gas inlet formed in one or both
of laminated films constituting front and back faces of the gas
channel, the gas inlet allowing the gas channel to communicate with
outside of the bag; and after the filling step of filling the bag
with the filling material, a gas replacement step is performed in
which an inert gas is blown through the gas inlet into the gas
channel and is blown through the gas channel into the bag to
replace air inside the bag with the inert gas, and then a gas inlet
sealing step of sealing the gas inlet and a bag mouth sealing step
of sealing the bag mouth are performed.
7. The bag packaging method according to claim 6, wherein the gas
replacement step: places a blowing outlet of a nozzle, which is
connected to an inert gas supply source, against the gas inlet, and
blows the inert gas from the gas inlet into the gas channel.
8. The bag packaging method according to claim 7, wherein a horn
and an anvil of an ultrasonic sealing device are disposed on both
sides of the bag equipped with the gas channel with the bag in
between, an inert gas channel is formed in the horn and/or the
anvil so that one end of the gas channel is connected to the inert
gas supply source and another end thereof opens to a distal end of
the horn and/or the anvil, the horn and/or the anvil in which the
inert gas channel is formed serving also as the nozzle, and the
other end of the inert gas channel being used as the blowing
outlet, and in the gas replacement step, the inert gas is blown
from the gas inlet into the gas channel by the horn and/or the
anvil, and the gas inlet sealing step is carried out by the horn
and the anvil.
9. The bag packaging method according to claim 6, wherein during
conveyance of the bag along the conveyance path, the gas
replacement step is intermittently carried out a plurality of
times.
10. The bag packaging method according claim 6, wherein the bag
mouth is pulled taut by increasing spacing between the pair of bag
conveyance grippers, either after completion of the gas replacement
step or during time between before start and completion of the gas
replacement step.
11. The bag packaging method according to any one of claims 6 to
10, wherein an intermittent sealed part formation step of
intermittently forming a sealed part along the bag mouth is
performed near the bag mouth between the filling step and the gas
replacement step.
12. A bag packaging apparatus, in which a pair of bag conveyance
grippers clamp side edges of a bag to hang down the bag while
conveying the bag along a specific conveyance path, and packaging
steps comprising opening up of a bag mouth, filling of the bag with
a filling material, replacing of air inside the bag with an inert
gas, and sealing of the bag mouth are successively carried out
during conveyance of the bag, wherein the bag is comprised of: a
sealed part provided in a bottom edge and both side edges of the
bag in which laminated films that constitute front and back faces
of the bag are sealed, a gas channel where the laminated films that
constitute the front and back faces of the bag are not fused, the
gas channel being formed in the sealed part, and a part of the gas
channel opening into the bag, and a gas inlet formed in one or both
of laminated films constituting front and back faces of the gas
channel, the gas inlet allowing the gas channel to communicate with
outside of the bag; and the packaging apparatus is comprised of a
bag mouth opening device, a material filling device, a gas
replacement device, and a bag mouth sealing device, which are
disposed along the conveyance path, in which the gas replacement
device comprises a nozzle that is connected to an inert gas supply
source, blows an inert gas out from a blowing outlet provided at a
distal end thereof and blows the inert gas from the gas inlet into
the gas channel of the bag, the bag mouth sealing device comprises
a pair of sealing members that clamp and seal the bag mouth from
both sides of the bag, and a gas inlet sealing device that seals
the gas inlet of the bag after gas replacement is further disposed
along the conveyance path, the gas inlet sealing device comprising
a pair of sealing members that clamp and seal the gas inlet from
both sides of the bag.
13. The bag packaging apparatus according to claim 12, wherein the
gas inlet is formed in both of the laminated films constituting the
front and back faces of the bag, and the gas replacement device
comprises a pair of nozzles that are disposed to face each other
and connected to the inert gas supply source, thus blowing the
inert gas out of the blowing outlet provided at the distal end.
14. The bag packaging apparatus according to claim 12, wherein the
gas replacement device comprises a nozzle, which is connected to
the inert gas supply source and blows the inert gas out of the
blowing outlet provided at the distal end, and a receiving member,
which is disposed to face the nozzle and supports the back face
side of the bag.
15. The bag packaging apparatus according to claim 12, wherein the
bag mouth sealing device serves also as the gas inlet sealing
device, and the pair of sealing members of the bag mouth sealing
device clamp and seal the bag mouth and the gas inlet from both
sides of the bag.
16. The bag packaging apparatus according to claim 13, wherein the
bag mouth sealing device serves also as the gas inlet sealing
device, and the pair of sealing members of the bag mouth sealing
device clamp and seal the bag mouth and the gas inlet from both
sides of the bag.
17. The bag packaging apparatus according to claim 14, wherein the
bag mouth sealing device serves also as the gas inlet sealing
device, and the pair of sealing members of the bag mouth sealing
device clamp and seal the bag mouth and the gas inlet from both
sides of the bag.
18. A bag packaging method, in which a pair of bag conveyance
grippers clamp side edges of a bag to hang down the bag while
conveying the bag along a specific conveyance path, and packaging
steps comprising opening up of a bag mouth, filling of the bag with
a filling material, replacing of air inside the bag with an inert
gas, and sealing of the bag mouth are successively carried out
during conveyance of the bag, wherein the bag is comprised of: a
sealed part provided in a bottom edge and both side edges of the
bag in which laminated films that constitute front and back faces
of the bag are sealed, a gas channel where the laminated films that
constitute the front and back faces of the bag are not fused, the
gas channel being formed in the sealed part, and a part of the gas
channel opening into the bag, and a gas inlet formed in one or both
of laminated films constituting front and back faces of the gas
channel, the gas inlet allowing the gas channel to communicate with
outside of the bag; and the packaging apparatus is comprised of a
bag mouth opening device, a material filling device, an ultrasonic
sealing device, and a bag mouth sealing device, which are disposed
along the conveyance path, in which the ultrasonic sealing device
is provided such that the ultrasonic sealing device is comprised of
a horn and an anvil in which an inert gas channel is formed in the
horn and/or the anvil so that one end of the gas channel is
connected to an inert gas supply source and an other end thereof
opens to a distal end of the horn and/or the anvil, the other end
of the inert gas channel is used as a blowing outlet of the inert
gas, the inert gas is blown from the gas inlet into the gas channel
by the horn and/or the anvil in which the inert gas channel is
formed, and the gas inlet is sealed by the horn and the anvil; and
the bag mouth sealing device comprises a pair of sealing members
that clamp and seal the bag mouth from both sides of the bag.
19. The bag packaging apparatus according to any one of claims
12-18, wherein an intermittent sealed part formation device, which
makes a sealed part formed intermittently along the bag mouth near
the bag mouth, is disposed next to the material filling device
along the conveyance path.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a bag and a method and
apparatus that includes a gas replacement step, in which the air
inside the bag filled with filling material is replaced with an
inert gas
[0003] 2. Description of the Related Art [0004] [Patent Reference
1] Japanese Patent Application Laid-Open (Kokai) No. 54-58592
[0005] [Patent Reference 2] Japanese Patent Application Publication
(Kokoku) No. 58-52890 [0006] [Patent Reference 3] Japanese Patent
Application Laid-Open (Kokai) No. 2013-233946
[0007] FIGS. 1 to 8 of Patent Reference 1 describes that the bag
mouth of a bag sealed along the bottom edge and both side edges is
opened, a gas nozzle (inert gas supply pipe) and a hopper (material
filling pipe) are inserted into the bag, inert gas is blown through
the gas nozzle into the bag, then the bag is filled with filling
material through the hopper, during which time the blowing of the
inert gas is continued to replace the air inside the bag with the
inert gas, and then after which the gas nozzle and the hopper are
pulled out of the bag at the same time, the bag mouth is next
pulled taut and closed, and after which the bag mouth is clamped
between a pair of hot plates, so that the bag mouth is sealed.
[0008] In FIGS. 9 to 17 of this Patent Reference 1, it is shown
that after filling a bag with the filling material, the hopper is
pulled out of the bag, the bag mouth is pulled taut and closed, and
after an inert gas is blown into the bag for a while, the gas
nozzle is pulled out of the bag, and then the bag mouth is clamped
between a pair of hot plates, so that the bag mouth is sealed.
[0009] With the method described in Patent Reference 1, the inert
gas starts to be blown in before adding the filling material, the
bag is filled with the filling material after the air in the bag
has been replaced with the inert gas, and the inert gas is allowed
to continue to be blown in to replace the air present in gaps in
the filling material with the inert gas. An effective gas
replacement thus can be performed.
[0010] Although in Patent Reference 1 the gas nozzle is inserted
into the bag before the bag is filled with the filling material, a
method in which a gas nozzle is inserted into a bag after adding
the filling material and the blowing outlet is positioned in the
middle of the filling material for gas replacement is also commonly
performed (see Patent Reference 3).
[0011] In Patent Reference 2, after adding the filling material,
the bag mouth is pulled taut while leaving the gas nozzle inside
the bag, then a pair of clamping plates are applied to the bag
mouth to close it, after which the gas nozzle is pulled out of the
bag, and the bag mouth is clamped and sealed with a pair of hot
plates.
[0012] In Patent Reference 3, a cylindrical protective member is
provided around the gas nozzle, so that the inner face of the bag
mouth comes into contact with the outer peripheral face of the
protective member when the bag mouth is pulled taut, and the gas
nozzle is raised and accommodated in the interior of this
protective member at the end of the gas replacement, and then the
gas nozzle is raised together with the protective member and
separated from the bag.
[0013] When, as described in Patent Reference 1, the bag mouth is
pulled taut to the left and right direction while the inert gas
continues to be blown in, and the gas nozzle is thereafter pulled
out of the bag, it is possible to prevent air flown into the bag at
the end of the gas replacement, and more effective gas replacement
is thus performed. Also, when, as described in Patent Reference 2,
the bag mouth is closed by applying a pair of clamping plates, and
then the gas nozzle is pulled out of the bag, it is possible to
prevent the inflow of air into the bag more reliably.
[0014] However, in the gas replacement methods described in Patent
References 1 and 2, since the blowing outlet at the lower end of
the gas nozzle is positioned within the filling material filled in
the bag, the filling material adheres to the outer peripheral face
near the blowing outlet of the gas nozzle. On the other hand, when
the gas nozzle is pulled out of the bag, since the bag mouth is
closed, the gas nozzle is pulled out of the bag while its outer
peripheral face rubs against the inner face of the bag mouth. As a
result, when the gas nozzle is pulled out through the bag mouth,
the filling material that has adhered to the outer peripheral face
of the gas nozzle sticks to the inner face of the mouth, which is
the place that is to be sealed, so that poor sealing known as pinch
sealing occurs when the bag mouth is sealed in a later step.
[0015] In the gas replacement method described in Patent Reference
3, when the gas nozzle is pulled out of the bag, the gas nozzle is
accommodated inside the protective member and does not come into
direct contact with the inner face of the bag mouth. Accordingly,
filling material that has adhered to the outer peripheral face of
the gas nozzle is prevented from sticking to the mouth inner face,
which is the place to be sealed. However, in this method of Patent
Reference 3, since the gas nozzle is inserted into the bag after
the filing of the bag with the filling material, if the filling
material is something that is soft (such as cooked beans), the
filling material can be damaged by the gas nozzle.
BRIEF SUMMARY OF THE INVENTION
[0016] The present invention is conceived in light of the
above-described problems seen in the prior art pertaining to gas
replacement, and it is an object of the present invention to
provide a bag that has a gas channel and to provide a method and
apparatus for packaging the bag, and in the present invention, the
air (including any air present in gaps in the filling material) in
a bag is efficiently replaced with an inert gas just as in the
past, and adhesion of filling material to the bag mouth inner face
and resulting pinch sealing are prevented, and further damages to
the filling material are prevented as well.
[0017] The bag according to the present invention (a bag equipped
with a gas channel) has sealed parts where the laminated films
constituting the front and back faces of the bag are sealed at the
bottom edge and the side edges, and a gas channel where the
laminated films constituting the front and back faces are not fused
is formed in the sealed parts, and also a part of the gas channel
opens into the bag, and further a gas inlet that allows the gas
channel to communicate with the outside of the bag is formed in one
or both of the laminated films that constitute the front and back
faces of the gas channel.
[0018] The above-described bag of the present invention can take
the following embodiments, for example:
[0019] (1) The gas channel is formed in a side edge sealed part or
is formed continuously with a side edge and bottom edge sealed
parts, and the gas inlet is formed at the upper end of the gas
channel.
[0020] (2) In the structure (1) above, the gas channel is formed in
the side edge sealed part, and the lower part of the gas channel is
opened into the bag.
[0021] (3) The bag is a finished bag in which the bag is filled
with its filling material, the air inside the bag is replaced with
an inert gas, and the bag mouth at the top edge and the gas inlet
are sealed.
[0022] (4) In the bag (3) above, a sealed part that continues
intermittently along the bag mouth is formed near the sealed mouth
of the bag.
[0023] In the bag packaging method according to the present
invention, the side edges of a bag are clamped by a pair of bag
conveyance grippers, and the bag hangs down while being conveyed
along a specific conveyance path, and such packaging steps as
opening up of the bag mouth, filling of the bag with its filling
material, replacing of the air inside the bag with an inert gas,
sealing of the bag mouth, and others are successively carried out
in the course of this conveyance,
[0024] wherein [0025] the bag is the one that is equipped with a
gas channel, in which sealed parts where the laminated films
constituting the front and back faces of the bag are sealed at the
bottom edge and the side edges of the bag are provided, a gas
channel where the laminated films constituting the front and back
faces are not fused is formed in the sealed parts, a part of the
gas channel opens into the bag, and a gas inlet that allows the gas
channel to communicate with the outside of the bag is formed in one
or both of the laminated films constituting the front and back
faces of the gas channel, and [0026] after a filling step of
filling this bag with its filling material, a gas replacement step
is performed so that an inert gas is blown through the gas inlet
into the gas channel and is blown through the gas channel into the
bag to replace the air inside the bag with the inert gas, and then,
after this gas replacement step, a gas inlet sealing step to seal
the gas inlet and a bag mouth sealing step to seal the bag mouth
are performed.
[0027] The above-described bag packaging method of the present
invention can take the following embodiments, for example:
[0028] (1) In the gas replacement step, the blowing outlet of a
nozzle connected to an inert gas supply source is placed against
the gas inlet, and the inert gas is blown from the gas inlet into
the gas channel.
[0029] (2) An ultrasonic sealing device including a horn and an
anvil is employed. The horn and the anvil are disposed so that they
are on either side of a bag that is equipped with a gas channel, an
inert gas channel is formed in the horn and/or anvil so that one
end thereof is connected to an inert gas supply source and another
end thereof opens to the distal end of the horn and/or anvil, the
horn and/or the anvil in which the inert gas channel is formed
serves also as the nozzle, the other end of the inert gas channel
is used as the blowing outlet, so that in the gas replacement step,
an inert gas is blown into the inert gas channel by the horn and/or
the anvil, and the horn and the anvil carry out the gas inlet
sealing step.
[0030] (3) The bag mouth is pulled taut by increasing the spacing
between the pair of bag conveyance grippers, either after
completion of the gas replacement step or during the time between
the start and completion of the gas replacement step.
[0031] (4) An intermittent sealed part formation step in which a
sealed part is formed intermittently along the bag mouth is
performed near the bag mouth between the filling step and the gas
replacement step.
[0032] In the bag packaging apparatus according to the present
invention, the side edges of a bag are clamped by a pair of bag
conveyance grippers, and the bag hangs down while being conveyed
along a specific conveyance path, and such packaging steps as
opening up of the bag mouth, filling of the bag with its filling
material, replacing of the air inside the bag with an inert gas,
sealing of the bag mouth, and others are successively carried out
in the course of this conveyance,
[0033] wherein [0034] the bag is the one that is equipped with a
gas channel, in which sealed parts where the laminated films
constituting the front and back faces of the bag are sealed at the
bottom edge and the side edges of the bag are provided, a gas
channel where the laminated films constituting the front and back
faces are not fused is formed in the sealed parts, a part of the
gas channel opens into the bag, and a gas inlet that allows the gas
channel to communicate with the outside of the bag is formed in one
or both of the laminated films constituting the front and back
faces of the gas channel, and [0035] a bag mouth opening device, a
material filling device, a gas replacement device, and a bag mouth
sealing device are disposed along the conveyance path, in which,
[0036] the gas replacement device includes a nozzle that is
connected to an inert gas supply source, blows an inert gas out
from the blowing outlet provided at its distal end, and blows the
inert gas from the gas inlet into the gas channel, and [0037] the
bag mouth sealing device includes a pair of sealing members that
clamp and seal the bag mouth from both sides of the bag, and [0038]
a gas inlet sealing device that seals the gas inlet of the bag
after gas replacement is further disposed along the conveyance
path, the gas inlet sealing device including a pair of sealing
members that clamp and seal the gas inlet from both sides of the
bag.
[0039] The above-described bag packaging apparatus of the present
invention can take the following embodiments, for example:
[0040] (1) The gas inlet is formed in both of the laminated films
constituting the front and back faces of the bag, and the gas
replacement device comprises a pair of nozzles that are disposed to
face each other and connected to an inert gas supply source and
blows the inert gas out of the blowing outlet which is provided at
its distal end.
[0041] (2) The gas replacement device includes a nozzle, which is
connected to an inert gas supply source and blows an inert gas out
of the blowing outlet which is provided at its distal end, and a
receiving member, which is disposed opposite to face the nozzle and
supports the back face side of the bag.
[0042] (3) The bag mouth sealing device serves also as the gas
inlet sealing device, and the pair of sealing members of the bag
mouth sealing device clamp and seal the bag mouth and the gas inlet
from both sides of the bag. In this structure, an independent gas
inlet sealing device is not required.
[0043] (4) An ultrasonic sealing device is used as the gas inlet
sealing device and this ultrasonic sealing device serves also as a
gas replacement device. In the ultrasonic sealing device, an inert
gas channel is formed in a horn and/or anvil in which one end
thereof is connected to an inert gas supply source and another end
thereof opens to the distal end of the horn and/or anvil, the other
end of the inert gas channel is used as the blowing outlet, an
inert gas is blown into the inert gas channel by the horn and/or
the anvil in which the inert gas channel is formed, and the horn
and the anvil seal the gas inlet.
[0044] (5) An intermittent sealed part formation device, which
makes a sealed part formed intermittently along the bag mouth near
the bag mouth, is disposed next to the material filling device in
the conveyance path.
[0045] As seen from the above, according to the present invention,
the air (including any air present in the gaps in the filling
material) in a bag can be efficiently replaced with an inert gas,
and at the same time, adhesion of the filling material to the bag
mouth inner face and resulting pinch sealing can be prevented, and
further damages to the filling material can also be prevented.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0046] FIG. 1 is a perspective view of a bag packaging apparatus
according to the present invention;
[0047] FIG. 2 is a front view of the bag (empty bag) according to
the present invention with the hatchings indicating the sealed
parts;
[0048] FIG. 3 is a front view of an ultrasonic sealing device
provided in the packaging apparatus shown in FIG. 1;
[0049] FIGS. 4A through 4C are front views of the gas replacement
step performed by the bag packaging apparatus of FIG. 1, being
illustrated in time sequence;
[0050] FIGS. 5A through 5C are side views respectively
corresponding to FIGS. 4A through 4C;
[0051] FIGS. 6A through 6C are front views of the gas replacement
step performed by the packaging apparatus of FIG. 1, being
illustrated in time sequence;
[0052] FIGS. 7A through 7C are side views respectively
corresponding to FIGS. 6A through 6C;
[0053] FIG. 8 is a front view of a bag (finished bag) according to
the present invention with the hatchings indicating the sealed
parts;
[0054] FIGS. 9A through 9D are front views of bags (empty bags)
each having a gas channel in different modes from that of the bag
shown in FIG. 2 with the hatchings indicating the sealed parts;
and
[0055] FIGS. 10A through 10C are front views of a bag and packaging
method according to another manner of the present invention, being
illustrated in time sequence.
DETAILED DESCRIPTION OF THE INVENTION
[0056] A bag equipped with a gas channel and a packaging method and
apparatus therefor according to the present invention will be
described below in detail with reference to FIGS. 1 to 10C.
[0057] First, FIG. 2 illustrates a gas channel-equipped bag 1
(hereinafter referred to simply as a bag 1). The bag 1 is comprised
of laminated films constituting the front and back faces of the
bag, and these films have sealed parts 2, 3 and 4 on both side
edges and the bottom edge, respectively. The side edge sealed part
2 is formed wider than the other side edge sealed part 3. Part of
the side edge sealed part 2 is an unsealed part where the films
constituting the front and back faces are not fused together, and
this unsealed part makes a gas channel 5. The gas channel 5 is
located at the place where the films constituting the front and
back faces of the bag 1 are not pressed and sealed in the
heat-sealing, and it extends downward in a narrow shape from near
the mouth 6 (the upper end of the sealed part 2) of the bag 1.
[0058] A gas inlet 5a that allows the gas channel 5 to communicate
with the outside of the bag is formed in part (the upper end in
this example) of the gas channel 5. The gas inlet 5a is
approximately circular, and its diameter is larger than the width
of the other portions of the gas channel 5. The gas inlet 5a is
formed with a cross-shaped cutout 8 at the center of the films
constituting the front and back faces. Also, part (the lower end in
this example) of the gas channel 5 opens into the interior of the
bag 1. This portion opening into the interior of the bag 1 is
called a communicating portion 5b of the gas channel 5. When an
inert gas is blown from the gas inlet 5a into the gas channel 5,
the inert gas flows down through the gas channel 5 and is blown
from the communicating portion 5b into the interior of the bag 1.
The "inert gas" referred to in the present invention encompasses
argon gas, helium gas, and other such noble gas elements as well as
nitrogen gas and other such elements having low chemical
reactivity.
[0059] FIG. 1 shows a packaging apparatus 9 according to the
present invention. The packaging apparatus 9 is a rotary packaging
apparatus, and it is similar to the rotary packaging apparatus
shown in, for example, FIG. 2 of Japanese Patent Application
Laid-Open (Kokai) No. 2014-139090. The packaging apparatus 9
comprises a bag conveyance device 14 in which a plurality of pairs
(ten pairs) of left and right bag conveyance grippers 12 and 13 are
installed at an equidistant spacing around a table 11 that rotates
intermittently and counter-clockwise by a specific angle each time.
In this bag conveyance device 14, the bag conveyance grippers 12
and 13 grasp both side edges (the sealed parts 2 and 3) of the bag
1 supplied thereto so that the bag hangs down and intermittently
convey the bags 1 around a circular conveyance path formed by the
table. The spacing between the gripers 12 and 13 are increased or
decreased during the course of the conveyance at a specific timing.
After a bag 1 is supplied to the grippers 12 and 13, the bag 1 that
is grasped by the grippers 12 and 13 is successively subjected to
various packaging steps at various positions (the stop positions I
to X) at which the grippers 12 and 13 stop, including the step of
opening up of the bag mouth, filling the bag with the filling
material, and sealing the mouth of the bag. A gas replacement step
and a gas inlet sealing step are further performed.
[0060] Each of the grippers 12 and 13 is composed of a pair of grip
pieces. As shown in FIG. 4A, the gripper 12 grasps the sealed part
2 of the bag so as to cross over the gas channel 5 horizontally. A
shallow groove 16 that runs in the up and down direction is formed
on the inside (the gripping side) of one or both of the grip pieces
of the gripper 12; and when the gripper 12 grasps the sealed part
2, this groove(s) 16 is superposed over the gas channel 5, so that
the gas channel 5 is not flattened (not blocked off) by the gripper
12.
[0061] In the packaging apparatus 9, a conveyor magazine type bag
supplier 17 is disposed at the stop position I of the conveyance
path. Furthermore, a printing device (only its head 18 is shown) is
disposed at the stop position II, a print inspection device (only
its head 19 is shown) is disposed at the stop position III, an
opening device that includes a pair of suction cups (only one
suction cup 21 is shown) is disposed at the stop position IV, a
material filling device (only its hopper 22 is shown) is disposed
at the stop position V, a first gas replacement device (only a pair
of nozzles 24 thereof is shown) is disposed at the stop position
VI, a second gas replacement device (only a pair of nozzles 25
thereof is shown) is disposed at the stop position VII, a third gas
replacement device (only a horn 26 and an anvil 27 thereof are
shown) is disposed at the stop position VIII, a bag mouth sealing
device (only a pair of hot plates 28 thereof is shown) is disposed
at the stop position IX, and a cooling device (only a pair of
cooling plates 29 thereof is shown) is disposed at the stop
position X.
[0062] The gas supply means shown in FIGS. 16 and 17 of Japanese
Patent Application Laid-Open (Kokai) No. 2014-139090 (only a pair
of nozzles 43 and 44 thereof disposed to face each other are shown
therein) can be used as the first and second gas replacement
devices disposed at the stop positions VI and VII of the packaging
apparatus 9. Alternatively, the gas supply means shown in FIGS. 3
and 4 of Japanese Patent Application Laid-Open (Kokai) No.
2014-139090 (only the nozzle 28 and the receiving member 29, which
are disposed to face each other, are shown therein) can also be
used as needed.
[0063] The pair of nozzles 24 of the first gas replacement devices
are connected to an inert gas supply source (not shown). These
nozzles 24 are disposed to face each other with the conveyance path
of the bag 1 in between. The nozzles 24 are moved forward (so as to
get closer to the conveyance path) or backward (so as to get away
from the conveyance path) with respect to the bag 1 stopped at that
stop position VI, and their distal end blowing outlets 24a (see
FIG. 5A) are provided so as to be placed against the gas inlet 5a
of the bag when they are in the forward position. A specific narrow
spacing L (somewhat wider than the thickness of the bag 1) is
provided between the blowing outlets 24a at the forward position of
the nozzle 24 (see FIG. 5B), and this spacing L is maintained when
the inert gas is being blown in. This spacing L is secured so the
blowing in of the gas (inert gas) from the gas inlet 5a into the
gas channel 5 of the bag is not hindered as described in Japanese
Patent Application Laid-Open (Kokai) No. 2014-139090. When the
nozzles 24 are both moved back to their retracted position (see
FIG. 5C), interference thereof with the bag 1 being conveyed along
the conveyance path is avoided. The forward and backward direction
of the nozzles 24 is, as can be seen from the above, perpendicular
to the bag 1.
[0064] The pair of nozzles 25 of the second gas replacement device
have exactly the same structure and make the same movement as the
pair of nozzles 24 of the first gas replacement device do.
[0065] FIG. 3 shows an ultrasonic sealing device 31, which is a
main component of the third gas replacement device disposed at the
stop position VIII. This ultrasonic sealing device 31 comprises the
horn 26 and anvil 27, an ultrasonic vibration generator 32 that
vibrates the horn 26, and an air cylinder 33 that moves the horn 26
and the anvil 27 back and forth. Attachment members 36 and 37 are
fixed to the distal ends of piston rods 34 and 35 of the air
cylinder 33, respectively. The ultrasonic vibration generator 32 is
fixed to the attachment member 36, and the anvil 27 is fixed to the
attachment member 37. The ultrasonic sealing device 31 thus
structured further includes a cooling means (not shown), and the
ultrasonic vibration generator 32, the horn 26, and the anvil 27
are cooled by this cooling means.
[0066] A hole (inert gas channel) 39 is formed in the interior of
the horn 26, and one end of this inert gas channel 39 opens to a
side face of the horn 26 and is connected to an inert gas supply
source 43 via a connector 41, a pipe 42, and a switch valve or the
like (not shown), while the other end of the inner gas channel 39
opens to the distal (forward) end of the horn 26 and thus makes an
inert gas blowing outlet 44. The anvil 27 also has a hole (inert
gas channel) 45 formed in its interior. One end of this inert gas
channel 45 opens to the rear end of the anvil 27 and is connected
to the inert gas supply source 43 via a connector 46 and a pipe 47,
and the other end of the gas channel 45 opens to the distal
(forward) end of the anvil 27 and makes an inert gas blowing outlet
48.
[0067] The horn 26 and the anvil 27 of the ultrasonic sealing
device 31 are disposed to face each other with the conveyance path
of the bag 1 in between. They are moved forward (to get closer to
the conveyance path) or backward (to get away from the conveyance
path) by the air cylinder 33 with respect to the bag 1 stopped at
that stop position VIII, symmetrically to each other. The air
cylinder 33 is a three-position type, so that the horn 26 and the
anvil 27 are stopped at their retracted position, which is the
farthest away from the conveyance path (see FIG. 7A), at their
forward position where their distal ends clamp (or hold) the bag 1
(see FIG. 7C), and at a blowing position which is between the
retracted position and the forward position (see FIG. 7B). The
forward and backward direction of the horn 26 and anvil 27 is
perpendicular to the bag 1. It is provided so that when the horn 26
and the anvil 27 have been moved to the retracted position,
interference with the bag 1 being conveyed along the conveyance
path can be avoided and that when the horn 26 and the anvil 27 have
been moved to the blowing position, a specific narrow spacing M
(somewhat wider than the thickness of the bag 1) is left between
the blowing outlets 44 and 48, and this spacing is maintained for a
specific length of time.
[0068] A packaging method that uses the packaging apparatus 9 shown
in FIG. 1 will now be described below with reference to FIGS. 1 to
8.
[0069] (1) At the stop position I (bag feed step position), a bag 1
is supplied from the conveyor magazine-type bag supplier 17 to the
pair of grippers 12 and 13 that have been stopped there, and the
grippers 12 and 13 grasp the specific locations of the sealed parts
2 and 3 from the front and back faces of the bag 1. The gripper 12
at this point grasps a location that is somewhat below the gas
inlet 5a of the bag (see FIG. 4A). In this case, the gas channel 5
is not flattened (or not blocked off) because the groove 16 (see
FIG. 4A), which is formed on the inside of the grip pieces of one
or both of grippers and runs in the up and down direction, cover(s)
the gas channel 5 from above.
[0070] (2) At the stop position II (printing step position), the
bag 1 stopped at this position is printed on its surface by the
printing device (see the head 18).
[0071] (3) At the stop position III (print inspection step
position), the bag 1 stopped at this position is subjected to print
inspection by the print inspection device (see the head 19).
[0072] (4) At the stop position IV (opening step position), the
mouth 6 of the bag 1 stopped at this position is opened up by the
opening device. A pair of suction cups 21 of this opening device
(only one suction cup 21 is shown in FIG. 1) are provided so as to
move forward and backward with respect to the bag 1. When they are
moved forward, they suction-hold the films on both sides of the bag
1 and then moved backward while still holding the films, thus
opening up the mouth 6 of the bag. At the same time, the grippers
12 and 13 narrow the gap between them (see FIG. 4A). Next, an
opening head (not shown; see the opening head 26 shown in FIG. 2 of
Japanese Patent Application Laid-Open (Kokai) No. 2014-139090) of
the opening device descends, its lower end goes through the mouth 6
into the bag 1, and air is blown into the bag 1 to inflate the
bag.
[0073] (5) At the stop position V (material filling step position),
the bag 1 stopped at this position is filled with filling material
23 by the material filling device. The hopper 22 of this filling
device is raised above the bag 1 then descended and is inserted
through the mouth 6 into the bag 1, so that the bag 1 is filled
with the filling material 23.
[0074] (6) The gas replacement step, which follows the filling
step, is performed three times in a first gas replacement step, a
second gas replacement step, and a third gas replacement step.
[0075] The first gas replacement device having the pair of nozzles
24 is disposed at the stop position VI (first gas replacement step
position). As shown in FIGS. 4A and 5A, when the filled bag 1
(hereinafter referred to as the filled bag 1A) is stopped at the
stop position VI, the nozzles 24 are in their refracted
position.
[0076] The nozzles 24 are then moved forward and reach the forward
position, the blowing outlets 24a of the nozzles approach the gas
inlet 5a from both sides of the filled bag 1A, and inert gas is
blown out as shown in FIGS. 4B and 5B. As a result, pressurized
inert gas is blown from the gas inlet 5a into the gas channel 5,
and this inert gas flows down through the gas channel 5 as
indicated by the arrow in FIG. 4B, and is blown from the
communicating portion 5b into the interior of the filled bag 1A,
and then it rises up through the gaps in the filling material 23 in
the filled bag 1A. Consequently, the air in the filled bag 1A
(including the air present in the gaps in the filling material 23)
is efficiently replaced with the inert gas. In FIG. 5B, the gas
channel 5 is shown in a manner that it has been inflated by the
pressure of the inert gas.
[0077] After a specific amount of time has passed, as shown in
FIGS. 4C and 5C, the blowing of the inert gas out of the blowing
outlets 24a of the nozzles 24 is halted, and the nozzles 24 are
moved back to their retracted positions.
[0078] (7) The second gas replacement device having the pair of
nozzles 25 is disposed at the stop position VII (second gas
replacement step position). At this stop position VII, the filled
bag 1A stopped there is again subjected to the same gas replacement
step as that performed at the stop position VI.
[0079] In these gas replacement steps, the timing of the starting
and stopping of the blowing of the inert gas out of the nozzles 24
and 25 is set as desired.
[0080] (8) The ultrasonic sealing device 31 shown in FIG. 3 is
disposed near the conveyance path of the bag 1A at the stop
position VIII (third gas replacement step and gas inlet sealing
step position), and the filled bag 1A stopped at this stop position
is subjected to the third gas replacement step and also to the
sealing step for the gas inlet 5a.
[0081] At the stop position VIII, the grippers 12 and 13 are spread
apart from each other while the filled bag 1A gripped by the
grippers 12 and 13 is being conveyed from the stop position VII to
the stop position VIII. Consequently, the places on the filled bag
1A grasped by the grippers 12 and 13 is pulled taut to the left and
right, which applies tension to and closes the upper part of the
filled bag 1A including the mouth 6.
[0082] When the filled bag 1A is stopped at the stop position VIII,
the horn 26 and anvil 27 are in their retracted positions as shown
in FIGS. 6A and 7A.
[0083] The ultrasonic sealing device 31 is then operated to move
the horn 26 and the anvil 27 forward until they reach positions
just short of their forward positions (the above-described blowing
position), the blowing outlets 44 and 48 of the horn and the anvil,
respectively are moved close to the gas inlet 5a from both sides of
the filled bag 1A, and inert gas is blown out therefrom as shown in
FIGS. 6B and 7B. As a result, pressurized inert gas is blown from
the gas inlet 5a into the gas channel 5, and this inert gas flows
down through the gas channel 5 as indicated by the arrow in FIG.
6B, and is blown from the communicating portion 5b into the
interior of the filled bag 1A, and then rises up through the gaps
in the filling material 23 inside the filled bag 1A, so that it
flows out from the mouth 6 to the outside of the bag. Since the
mouth 6 is closed, outside air is prevented from getting into the
bag through the mouth 6, so the air inside the filled bag 1A
(including the air present in the gaps in the filling material 23)
is replaced even more efficiently with the inert gas. In FIG. 7B,
the gas channel 5 is illustrated so that it that has been inflated
by the pressure of the inert gas.
[0084] After the horn 26 and anvil 27 are stopped at the blowing
position, the blowing of the inert gas out of the blowing outlets
44 and 48 is halted at a specific timing. Next, the air cylinder 33
is operated to move the horn 26 and the anvil 27 forward, and
ultrasonic vibrations are generated by the ultrasonic vibration
generator 32, and its vibration energy is supplied to the horn 26.
Consequently, as shown in FIGS. 6C and 7C, the distal ends of the
horn 26 and anvil 27 clamp the gas inlet 5a from both sides of the
filled bag 1A, the films constituting the front and back faces of
the gas inlet 5a (and particularly around the cutout 8) are
ultrasonically sealed thereby, and the gas channel 5 (the gas inlet
5a) is thus closed. As shown in FIG. 8, a ring-shaped
ultrasonically sealed part 51 (the ring-shaped sealed part is shown
by hatched lines) is formed to coincide with the shape of the part
clamped by the horn 26 and anvil 27 (the shape of the distal end
face 49 of the horn 26). Most or all of the cutout 8 itself is not
sealed by this ultrasonic sealing; however, since the films
constituting the front and back faces of the gas inlet 5a around
the cutout 8 are sealed, the gas channel 5 is closed assuredly.
[0085] As seen from the above, the ultrasonic sealing device 31
serves as both a gas replacement device and a gas inlet sealing
device. Accordingly, fewer steps are required, and the apparatus
takes up less installation space.
[0086] Furthermore, since the mouth 6 of the filled bag 1A is being
pulled taut by the pair of grippers 12 and 13, the position of the
gas inlet 5a is fixed, and thus there will tend to be fewer
misalignments between the positions of the horn 26 and anvil 27 and
the position of the gas inlet 5a upon arrival at the blowing
position and upon further forward movement to clamp the gas inlet
5a.
[0087] When the ultrasonic sealing is finished (or when the
generation of ultrasonic waves is finished), no more frictional
heat is generated by the ultrasonic vibration, and the
ultrasonically sealed part 51 clamped by the distal ends of the
horn 26 and anvil 27 is immediately cooled by the horn 26 and anvil
27. After the ultrasonic sealing is finished, the air cylinder 33
is operated in reverse with suitable timing, and as a result the
horn 26 and the anvil 27 are moved back to the above-described
retracted (or backward) position (see FIG. 3A).
[0088] (9) At the next stop position IX (sealing step position),
the pair of hot plates 28 clamp the mouth 6 of the bag 1A and
heat-seal it. The sealed part formed by this heat-sealing is
indicated by reference numeral 52 in FIG. 8.
[0089] (10) At the stop position X (sealed part cooling and
discharge step position), the pair of cooling plates 29 clamp and
cool the sealed part 52. During this cooling, the grippers 12 and
13 are opened up, then the cooling plates 29 are opened up as well,
and thus the filled bag 1A (hereinafter referred to as the finished
bag 1B) drops and is discharged to the outside of the apparatus by
a chute 53.
[0090] Another embodiment of the gas channel 5 will now be
described with reference to FIGS. 9A through 9D. Portions that are
substantially the same as those in the bag 1 shown in FIG. 2 will
be numbered with the same reference numbers.
[0091] The bag 54 shown in FIG. 9A has gas channels 5 formed in
both the sealed parts 2 and 3. The gas channels 5 of the bag 54
both have respectively gas inlets 5a at the upper ends and have
communicating portions 5b at the lower ends. In this bag 54, since
the communicating portions 5b that open to the interior of the bag
54 are formed on both lateral sides of the bag, inert gas can be
more thoroughly blown into the bag 54 (including the gaps in the
filling material), and more efficient gas replacement is
achieved.
[0092] The bag 55 shown in FIG. 9B has gas channel 5 formed in the
sealed part 2. The gas channel 5 has the gas inlet 5a formed in the
upper end of the gas channel 5 and has communicating portions 5b
formed at a plurality of places in the lower location. In this bag
55, since the communicating portions 5b that open into the interior
of the bag 55 are formed at a plurality of places in the up and
down direction, inert gas can be blown more uniformly into the
filling material that fills the bag 55, and as a result more
efficient gas replacement is achieved.
[0093] The bag 56 shown in FIG. 9C has gas channel 5 that is formed
continuously from the sealed part 2 on the side edge to the sealed
part 4 on the bottom edge. This gas channel 5 has the gas inlet 5a
formed at the upper end of the gas channel 5 and has communicating
portions 5b formed at a plurality of places in the sealed part 4.
In this bag 56, since the communicating portions 5b that open into
the interior of the bag 56 are formed at a plurality of places in
the width direction of the sealed part 4, inert gas can be blown
more uniformly into the bag 55 (including the gaps in the filling
material), and as a result more efficient gas replacement is
achieved.
[0094] The bag 57 shown in FIG. 9D has gas channel 5 formed from
one end of the sealed part 4 on the bottom edge to the center in
the width direction of the bag. This gas channel 5 has the gas
inlet 5a formed at one end of the gas channel 5 and has the
communicating portion 5b formed at the other end (so as to be
located at the center in the width direction of the bag). Since the
gas channel 5 is not formed in the sealed parts 2 and 3 on the side
edges, there is no need to increase the width of the sealed parts 2
and 3, and the gas channel 5 can be made shorter, which reduces
energy loss in the inert gas flowing through the gas channel 5.
When the gas inlet 5a is thus formed in the sealed part in the
bottom edge, a change in the length of the bag 57 will cause the
location of the gas inlet 5a to be changed in the up and down
direction. Accordingly, if the length of the bag changes (or when
bags of different length are processed), it will be necessary to
change the height of the nozzles 24 and 25 and the height of the
horn 26 and anvil 27.
[0095] Furthermore, in the packaging method according to the
present invention, a sealed part that continues intermittently
(intermittent sealed part) can be formed near and along the bag
mouth as needed after the bag is filled with the filling material.
In FIG. 10, a two-level (upper and lower) intermittent sealed part
58 is formed in the filled bag 1A. The intermittent sealed part 58
continues intermittently in the width direction of the bag,
including a plurality of unsealed parts 58a. In this example, the
unsealed parts 58a are formed in a relatively narrow width. The
intermittent sealed part itself is known (see Japanese Patent
Application Laid-Open (Kokai) No. 11-29153, for example).
[0096] The intermittent sealed part 58 can be formed, similar to
the sealed part 52, by an intermittent sealed part formation device
that includes a pair of hot plates. The timing that the
intermittent sealed part 58 is formed is preferably after the end
of the material filling step and before the start of the gas
replacement step. If the gas replacement step is conducted a
plurality of times, the intermittent sealed part 58 is preferably
formed before the first gas replacement step, although it can also
be formed between the plurality of gas replacement steps.
[0097] Part of the gas replacement step for a bag in which the
intermittent sealed part 58 is formed (and in particular a gas
replacement step that uses the ultrasonic sealing device 31) will
now be described with reference to FIGS. 10A through 10C.
[0098] (1) FIG. 10A corresponds to FIG. 6B, time sequence-wise. A
two-level intermittent sealed part 58 is formed near the mouth 6 of
the filled bag 1A in which the intermittent sealed part 58 has been
formed. The intermittent sealed part 58 is what is known as a "maze
seal", with the upper- and lower-level unsealed parts 58a formed in
a staggered manner (offset from one another).
[0099] The horn 26 and anvil 27 cause inert gas to be blown out
from their blowing outlets 44 and 48 (see FIG. 3), and the
pressurized inert gas is blown from the gas inlet 5a into the gas
channel 5, and then this inert gas flows down through the gas
channel 5 as indicated by the arrow and is blown from the
communicating portion 5b into the interior of the filled bag 1A.
The inert gas that has been blown into the interior of the filled
bag 1A rises up through the gaps in the filling material 23 in the
filled bag 1A, and as this occurs, the air in the filled bag 1A
(including any air present in the gaps in the filling material)
flows through the narrow passages in the intermittent sealed part
58 and goes out of the bag through the mouth 6.
[0100] If the filling material 23 is something that is extremely
lightweight, with a great number of thin shavings mixed in, such as
katsuobushi (dried bonito flake) or furikake (seasoned powdery
flavoring for sprinkling on rice), these lightweight small pieces
will tend to float up and be scattered outside the bag when the
inert gas is blown into the filled bag 1A. In the case of filled
bag 1A that has the intermittent sealed part 58 formed in it, even
if the filling material 23 should float up, it will be blocked by
the intermittent sealed part 58; accordingly, the advantage is that
the filling material 23 will tend not to be scattered out of the
bag. Therefore, compared to the filled bag 1A shown in FIG. 6A that
has no intermittent sealed part 58 formed, the gas replacement can
be finished in a shorter time by blowing in the inert gas under a
higher pressure.
[0101] (2) FIG. 10B corresponds to FIG. 6C, time sequence-wise.
Ultrasonic vibration energy is supplied from the ultrasonic
vibration generator 32 (see FIG. 3) to the horn 26, the horn 26 and
the anvil 27 are moved forward to clamp the gas inlet 5a from both
sides of the filled bag 1A, the films constituting the front and
back faces of the gas inlet 5a (and particularly around the cutout
8) of the bag are ultrasonically sealed, and the gas channel 5 is
closed.
[0102] (3) FIG. 10C shows a situation that the hot plates 28 clamp
and heat-seal the mouth 6 of the bag in the bag mouth sealing step.
In this example, the hot plates 28 are placed over part of the
intermittent sealed part 58 to seal it, and the remainder of the
intermittent sealed part 58 (one level) is located under the sealed
part 52.
[0103] Various embodiments of the bag equipped with a gas channel
and the packaging method and apparatus according to the present
invention are described above with reference to FIGS. 1 to 10C, and
in the present invention the embodiments below are also
possible:
[0104] (1) In the above-described examples, the bags 1 gripped by
grippers are intermittently conveyed along a circular conveyance
path, and specific packaging steps are carried out on each one of
the bags 1 at the various stop positions. The nozzles 24 and 25 and
the ultrasonic sealing device 31, however, can be moved
synchronously with the conveyance of bags and returned to their
initial positions after reaching the movement end positions, so
that the specific packaging steps are carried out while each one of
the bags 1 is being conveyed. In addition, the conveyance of the
bag 1 can be done continuously, and the conveyance path can be, for
instance, linear or in the shape of a racetrack rather than
circular.
[0105] (2) In the above examples, the gas replacement step is
performed three times intermittently. However, the number of times
of gas replacement can be set as desired, and it can be just
once.
[0106] (3) In the above examples, the spacing between the grippers
12 and 13 is increased before the third gas replacement step, and
the mouth of the bag 1 is pulled taut. However, this operation can
be performed whenever appropriate after the filling step, either
after completion of the gas replacement step or during the time
between the start and completion of the gas replacement step. If
the gas replacement step is carried out a plurality of times, this
can be performed whenever appropriate, either after completion of
the last gas replacement step or during the time between the start
of the first gas replacement step and completion of the last gas
replacement step. From the standpoint of increasing the gas
replacement efficiency, however, it is preferably performed after
the filling step and before the start of the gas replacement step
(if the gas replacement step involves a plurality of times, it
should be started no later than before the start of the last gas
replacement step).
[0107] (4) In the above examples, the sealing function of the
ultrasonic sealing device 31 is utilized, and the sealing step of
the gas inlet 5a after the third gas replacement step is performed
using this same ultrasonic sealing device 31. When the gas
replacement device, however, does not have the function of
performing the sealing step (such as when the gas is replaced by
the pair of nozzles 24), then a sealing device (such as one having
a pair of hot plates) must be installed to seal the gas inlet 5a
separately. Alternatively, the gas inlet 5a of the bag can be
simultaneously sealed by a sealing device that seals the bag mouth
(the bag mouth sealing device serving also as the gas inlet sealing
device).
[0108] (5) In the above examples, the bag 1 has the cutout 8 formed
in the films constituting the front and back faces of the gas inlet
5a of the bag; however, the cutout 8 of the gas inlet 5a can be
formed in just one of the films constituting either the front or
back face. In this case, no inert gas is blown out of the nozzle
disposed on the side where no cutout 8 is formed, or a receiving
member that has no blowing outlet is installed instead of this
nozzle. When an ultrasonic sealing device is used for this purpose,
no inert gas is blown out of the member that is disposed on the
side where no cutout 8 is formed, and an inert gas channel does not
need to be formed in that member. Also, a hole (see Japanese Patent
Application Laid-Open (Kokai) No. 2014-139090) can be formed the
inert gas inlet instead of the cutout 8.
* * * * *