U.S. patent application number 12/598784 was filed with the patent office on 2010-08-26 for air bag with pressurization space.
This patent application is currently assigned to INDIS AIR CORP. Invention is credited to Sung Jun Kim.
Application Number | 20100215293 12/598784 |
Document ID | / |
Family ID | 41721646 |
Filed Date | 2010-08-26 |
United States Patent
Application |
20100215293 |
Kind Code |
A1 |
Kim; Sung Jun |
August 26, 2010 |
AIR BAG WITH PRESSURIZATION SPACE
Abstract
An air bag includes two inner sheets facing each other, two
outer sheets located at an outer side of the two inner sheets, heat
resistance material located at an inner side of any one inner
sheet, a first thermal bonding line thermally bonding the two outer
sheets to form air input channel, a second thermal bonding line
thermally bonding the inner and outer sheets along the material
with gap from the first thermal bonding line, and third thermal
bonding lines extending from the second thermal bonding line
oppositely to the air input channel to form air pillars, a second
thermal bonding portion being formed to cross the third thermal
bonding lines to thermally bond the two inner and outer sheets to
form a pressurization space between the second thermal bonding
portion and line, and the second thermal bonding portion being
spaced apart from adjacent second thermal bonding portion to form a
second passage.
Inventors: |
Kim; Sung Jun; (Gyeonggi-do,
KR) |
Correspondence
Address: |
RENNER OTTO BOISSELLE & SKLAR, LLP
1621 EUCLID AVENUE, NINETEENTH FLOOR
CLEVELAND
OH
44115
US
|
Assignee: |
INDIS AIR CORP
Guro-dong, Guro-gu, Seoul
KR
|
Family ID: |
41721646 |
Appl. No.: |
12/598784 |
Filed: |
November 26, 2008 |
PCT Filed: |
November 26, 2008 |
PCT NO: |
PCT/KR2008/006965 |
371 Date: |
November 4, 2009 |
Current U.S.
Class: |
383/109 |
Current CPC
Class: |
B65D 81/03 20130101 |
Class at
Publication: |
383/109 |
International
Class: |
B65D 30/14 20060101
B65D030/14 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 25, 2008 |
KR |
10-2008-0082842 |
Claims
1. An air bag, comprising: two inner sheets positioned to face each
other; two outer sheets respectively located at an outer side of
the two inner sheets; a heat resistance material located at an
inner side of the two inner sheets and applied to any one of the
inner sheets; a first thermal bonding line for thermally bonding
the two outer sheets to form an air input channel; a second thermal
bonding line for thermally bonding the inner sheets and the outer
sheets along the heat resistance material with a gap from the first
thermal bonding line; and third thermal bonding lines extending
from the second thermal bonding line in a direction opposite to the
air input channel to form air pillars, wherein a second thermal
bonding portion is formed at the third thermal bonding lines in a
crossing direction thereof to thermally bond the two inner sheets
and the two outer sheets such that a pressurization space is formed
between the second thermal bonding portion and the second thermal
bonding line, and the second thermal bonding portion is spaced
apart from a second thermal bonding portion extending from another
adjacent third thermal bonding line to form a second passage.
2. The air bag according to claim 1, wherein fourth thermal bonding
lines with a length smaller than an interval between the third
thermal bonding lines extend from the third thermal bonding lines
in a lateral direction, and wherein the fourth thermal bonding
lines thermally bond the two inner sheets to any one of the outer
sheets, and the fourth thermal bonding lines are formed at an
opposite side to the second thermal bonding line with respect to
the second thermal bonding portion.
3. The air bag according to claim 1, wherein the heat resistance
material is continuously applied to the inner sheets in a length
direction, and the second thermal bonding line thermally bonds the
inner sheets and the outer sheets along the heat resistance
material.
4. The air bag according to claim 1, wherein a plurality of first
thermal bonding portions are formed in the air input channel in
correspondence to the third thermal bonding lines, respectively,
such that adjacent first thermal bonding portions are spaced apart
from each other to form a first passage, and wherein a part of the
first thermal bonding portions thermally bond the two outer sheets,
and the other part of the first thermal bonding portions thermally
bond the outer sheets to the inner sheets.
5. The air bag according to claim 1, wherein at least one thermal
bonding point for thermally bonding the two outer sheets in a
direction perpendicular to the air pillars is formed at a middle of
each air pillar in a length direction thereof.
6. The air bag according to claim 1, wherein both ends of the air
input channel are closed, and a cock is formed at any one of the
outer sheets corresponding to the air input channel.
Description
TECHNICAL FIELD
[0001] This disclosure relates to an air bag, and more particularly
to an air bag with an excellent sealing property by forming a
pressurization space in an air pillar, where a valve is positioned,
to press an inner sheet, thereby pressing the valve doubly.
BACKGROUND ART
[0002] During delivery of household necessaries or other important
articles, the contents are wrapped by an air bag so as to prevent
the contents from being broken by external impacts.
[0003] In the appended drawings, FIG. 1 is a perspective view
showing a general air bag, and FIG. 2 is a vertical sectional view
taken along the line A-A' of FIG. 1, which shows a valve of the air
bag shown in FIG. 1.
[0004] As shown in FIG. 1, the air bag 10 has a valve 20 that is
closed by an inner pressure of air injected into the air bag.
[0005] The air bag 10 has a rectangular structure, and an air input
channel 11 is formed along one side of the air bag 10. Also, a
plurality of air pillars 13 are perpendicularly formed with respect
to the air input channel 11. A plurality of valves 20 respectively
connect the air input channel 11 to the air pillars 13, so air
supplied through the air input channel 11 is introduced to each air
pillar 13 through the valves 20. If the air pillars 13 are filled
with air, inner pressure is generated to press the valves 20,
thereby sealing the air pillars 13 such that the air in the air
pillars 13 does not go out through the valves 20.
[0006] Referring to FIGS. 1 and 2, the air bag mentioned above is
explained in more detail. The air bag 10 includes two outer sheets
15 that form an overall configuration of the air bag. Also, the
valve 20 includes two inner sheets 21 positioned inside the two
outer sheets 15 and discontinuous heat resistance inks 23 applied
to any one of facing surfaces of the two inner sheets 21, and the
valve is formed by a plurality of thermal bonding lines 31, 32, 33,
and thermal bonding points 41, 42. In FIG. 1, the heat resistance
inks 23 applied to an inner side of the inner sheets 21 is depicted
as a dotted line.
[0007] In a state that the two inner sheets 21 are positioned in
the two outer sheets 15, the air input channel 11 is formed by a
first thermal bonding line 31 and a second thermal bonding line 32,
positioned in parallel with each other. At this time, the second
thermal bonding line 32 is formed while passing the heat resistance
inks 23 discontinuously formed along the inner sheets 21. Also, the
first thermal bonding line 31 bonds just the two outer sheets
15.
[0008] The air input channel 11 is formed along the first thermal
bonding line 31 and the second thermal bonding line 32 as mentioned
above, and one side of the air input channel 11 is closed and the
other side is opened. Air is injected through the other side that
is open.
[0009] The outer sheet 15 and the inner sheet 21 are bonded by the
second thermal bonding line 32, but regions where the heat
resistance inks 23 are formed are not bonded. Thus, the air
injected through the air input channel 11 is introduced to the air
pillars 13 through passages 25 between the inner sheets 21, which
are not thermally bonded because of the heat resistance inks
23.
[0010] In addition, the air pillars 13 are formed by third thermal
bonding lines 33 extending perpendicularly from the second thermal
bonding line 32, but the third thermal bonding lines 23 are
alternately formed with the passages formed by the heat resistance
inks 23. The air introduced to the air pillar 13 through the
passage 25 fills the air pillar 13 formed by the third thermal
bonding line 33.
[0011] Meanwhile, in a region of the two inner sheets 21 positioned
toward the air input channel 11 with respect to the second thermal
bonding line 32, one inner sheet 21 and one outer sheet 15 are
bonded and fixed to each other by means of the first thermal
bonding point 41. As the two outer sheets 15 are expanded due to
the injected air, the inner sheets 21 respectively bonded and fixed
by the first thermal bonding point 41 become wider in opposite
directions to open the passage 25.
[0012] However, the two inner sheets 21 positioned toward the air
pillar 13 with respect to the second thermal bonding line 32 are
bonded and fixed to any one outer sheet by the second thermal
bonding point 42 to close the valve 20 by the air filled in the air
pillar 13.
[0013] Thus, the passages 25 are closed due to the inner pressure
of the air pillars 13.
[0014] In such a general air bag, when air is injected to the air
input channel 11, the air is introduced to the air pillar 13
through the passage 25. After the air filled in the air pillar 13
is introduced between the inner sheet 21 and the outer sheet 15,
the air presses the two inner sheets 21 to close the passage
25.
[0015] In such a sealing method, a greater pressure is applied to a
curved region of the outer sheet 15, which is thermally bonded,
such as a region below the second thermal bonding line 32, than a
flat region of the expanded outer sheet. It is because the curved
region has a larger surface area than the flat portion, so pressure
is more greatly applied to the curved region. Thus, sealing is more
excellent as there are more curved regions. However, the general
air bag has only one curved region to which pressure is greatly
applied, namely the region below the second thermal bonding line,
so it does not have a good sealing property.
DISCLOSURE
Technical Problem
[0016] The disclosure is designed to solve the above problems, and
therefore the disclosure is directed to providing an air bag having
an improved sealing property by forming a pressurization space such
that air is not leaked, thereby sealing the air doubly.
Technical Solution
[0017] In one aspect, there is provided an air bag, which includes
two inner sheets positioned to face each other, two outer sheets
respectively located at an outer side of the two inner sheets, a
heat resistance material located at an inner side of the two inner
sheets and applied to any one of the inner sheets, a first thermal
bonding line for thermally bonding the two outer sheets to form an
air input channel, a second thermal bonding line for thermally
bonding the inner sheets and the outer sheets along the heat
resistance material with a gap from the first thermal bonding line,
and third thermal bonding lines extending from the second thermal
bonding line in a direction opposite to the air input channel to
form air pillars, wherein a second thermal bonding portion is
formed at the third thermal bonding lines in a crossing direction
thereof to thermally bond the two inner sheets and the two outer
sheets such that a pressurization space is formed between the
second thermal bonding portion and the second thermal bonding line,
and the second thermal bonding portion is spaced apart from a
second thermal bonding portion extending from another adjacent
third thermal bonding line to form a second passage.
[0018] Also, in one embodiment, fourth thermal bonding lines with a
length smaller than an interval between the third thermal bonding
lines may extend from the third thermal bonding lines in a lateral
direction, and the fourth thermal bonding lines may thermally bond
the two inner sheets to any one of the outer sheets, and the fourth
thermal bonding lines may be formed at an opposite side to the
second thermal bonding line with respect to the second thermal
bonding portion.
[0019] Also, in one embodiment, the heat resistance material may be
continuously applied to the inner sheets in a length direction, and
the second thermal bonding line may thermally bond the inner sheets
and the outer sheets along the heat resistance material.
[0020] Also, in one embodiment, a plurality of first thermal
bonding portions may be formed in the air input channel in
correspondence to the third thermal bonding lines, respectively,
such that adjacent first thermal bonding portions are spaced apart
from each other to form a first passage, and a part of the first
thermal bonding portions may thermally bond the two outer sheets
and the other part of the first thermal bonding portions may
thermally bond the outer sheets to the inner sheets.
[0021] Also, in one embodiment, at least one thermal bonding point
for thermally bonding the two outer sheets in a direction
perpendicular to the air pillars may be formed at a middle of each
air pillar in a length direction thereof.
[0022] Also, in one embodiment, both ends of the air input channel
may be closed, and a cock may be formed at any one of the outer
sheets corresponding to the air input channel.
ADVANTAGEOUS EFFECTS
[0023] As described above, the air bag disclosed herein exhibits an
excellent durability since the air filled in an air pillar is
sealed doubly to minimize air leakage.
[0024] In addition, the air bag disclosed herein is less restricted
in locations of thermal bonding lines and points since a heat
resistance ink is applied over the entire length of a valve, which
ensures easier work, thereby improving productivity and lowering an
inferiority rate.
DESCRIPTION OF DRAWINGS
[0025] The above and other aspects, features and advantages of the
disclosed exemplary embodiments will be more apparent from the
following detailed description taken in conjunction with the
accompanying drawings in which:
[0026] FIG. 1 is a perspective view showing a general air bag;
[0027] FIG. 2 is a vertical sectional view taken along the line
A-A' of FIG. 1, which shows a valve of the air bag shown in FIG.
1;
[0028] FIG. 3 is a plan view showing one embodiment of an air bag
disclosed herein;
[0029] FIG. 4 is a perspective view showing one embodiment of an
air bag disclosed herein;
[0030] FIG. 5 is a vertical sectional view taken along the line
C-C', which illustrates a valve while and after the process of
injecting air to the air bag shown in FIG. 4 is executed;
[0031] FIG. 6 is a perspective view showing another embodiment of
an air bag disclosed herein;
[0032] FIG. 7 is a sectional view taken along the line B-B', which
illustrates expansion of an air introduction channel and widening
of a first passage by the thermal bonding portion shown in FIG. 6;
and
[0033] FIG. 8 is a plan view showing another embodiment of an air
bag disclosed herein, to which a cock is mounted.
REFERENCE NUMERALS OF ESSENTIAL PARTS IN THE DRAWINGS
TABLE-US-00001 [0034] 100: air bag 101: air input channel 103: air
pillar 105: outer sheet 120: valve 121: inner sheet 140: heat
resistance ink 125A: first passage 125B: second passage 131-134:
thermal bonding line 151, 152: thermal bonding portion 139: thermal
bonding point 160: pressurization space 170: cock
BEST MODE
[0035] Hereinafter, preferred embodiments of the present invention
will be described. While the present invention is described with
reference to embodiments thereof, the technical idea and the
construction and operation of the invention are not limited to the
embodiments.
[0036] FIG. 3 is a plan view showing one embodiment of an air bag
disclosed herein, and FIG. 4 is a perspective view showing one
embodiment of an air bag disclosed herein.
[0037] As shown in FIGS. 3 and 4, an air bag 100 of this embodiment
includes two outer sheets 105 (see FIG. 5), two inner sheets 121
(see FIG. 5) that forms a valve 120, and a first thermal bonding
line 131 and a second thermal bonding line 132 that form an air
input channel 101. Also, the air bag of this embodiment includes a
third thermal bonding line 133 perpendicularly extending from the
second thermal bonding line 132 to form an air pillar 103, a fourth
thermal bonding line 134 for elongating a passage of air passing
through the valve 120 to improve sealing, and a second thermal
bonding portion 152 for forming a pressurization space 160 between
the second thermal bonding portion 152 and the second thermal
bonding line 132. The air bag of this embodiment also includes a
heat resistance ink 140 applied to any one of facing surfaces of
the two inner sheets 121. The heat resistance ink 140 is depicted
as a dotted line in FIGS. 3 and 4.
[0038] In a region of the two inner sheets 121 positioned toward
the air input channel 101 with respect to the second thermal
bonding line 132, one inner sheet 121 and one outer sheet 105 are
bonded and fixed to each other by means of the first thermal
bonding point 141.
[0039] Here, the fourth thermal bonding lines 134 are formed to
cross the third thermal bonding line 133 and thermally bond the two
inner sheets 121 to any one of the outer sheets to form an
elongated path of air passing through the valve 120. Thus, it is
possible to prevent air from being leaked reversely, thereby
improving sealing.
[0040] The second thermal bonding portion 152 is a thermal bonding
region formed with a greater thickness than the first to fourth
thermal bonding lines 131, 132, 133, 134, and the second thermal
bonding portion 152 has a smaller length than a gap between the
third thermal bonding lines 133. Here, a space between the second
thermal bonding line and the second thermal bonding portion 152 is
a pressurization space 160. The second thermal bonding portion 152
thermally bonds the two outer sheets 105 and the two inner sheets
121.
[0041] In a state that the two inner sheets 121 are positioned in
the two outer sheets 105, the air input channel 101 is formed by
the first thermal bonding line 131 and the second thermal bonding
line 132, positioned in parallel with each other. At this time, the
second thermal bonding line 132 is formed while passing the heat
resistance inks 140 discontinuously formed along the inner sheets
121. Also, the first thermal bonding line 131 bonds just the two
outer sheets 105.
[0042] The air input channel 101 is formed along the first thermal
bonding line 131 and the second thermal bonding line 132 as
mentioned above, and one side of the air input channel 101 is
closed and the other side is opened. Air is injected through the
other side that is open. Meanwhile, the outer sheet 105 and the
inner sheet 121 are bonded by the second thermal bonding line 132,
but regions where the heat resistance inks 140 are formed are not
bonded.
[0043] Also, the second thermal bonding portion 152 is formed to
cross the third thermal bonding line 133 between the second thermal
bonding line 132 and the fourth thermal bonding line 134. FIGS. 3
and 4 show that the second thermal bonding portion 152 is spaced
apart from the second thermal bonding line 132, but not limited
thereto. The second thermal bonding portion 152 may also be formed
continuously from the second thermal bonding line 132. The second
thermal bonding portion 152 is located spaced apart from a second
thermal bonding portion 152 formed on an adjacent third thermal
bonding line 133, thereby forming a second passage 125B through
which air may be introduced to the air pillar 103.
[0044] FIG. 5 is a vertical sectional view taken along the line
C-C', which illustrates a valve while and after the process of
injecting air to the air bag shown in FIG. 4 is executed.
[0045] Hereinafter, an air flow while air is injected to the air
input channel 101 of the air bag is explained with reference to
FIG. 5.
[0046] As seen from FIG. 5, if air is injected to the air input
channel 101 formed between the first thermal bonding line 131 and
the second thermal bonding line 132 using an air injector, the air
is injected along the air input channel 101 to expand the air input
channel 101.
[0047] If the air input channel 101 is expanded as mentioned above,
a gap between the two inner sheets 121 is widened, so the air is
introduced beyond the second thermal bonding line 132 into the
valve 120 between the third thermal bonding lines 133. As the two
outer sheets 105 are expanded due to the injected air, the inner
sheets 121 respectively bonded and fixed by the first thermal
bonding point 141 (see FIGS. 3 and 4) are widened in opposite
directions, thereby opening a passage through which air may be
introduced.
[0048] Meanwhile, the air introduced into the valve 120, namely
between the two inner sheets 121, passes through the second passage
125B between the second thermal bonding portions 152 (the second
passage 125B is not clearly shown in FIG. 5 since FIG. 5 is a
vertical sectional view taken along the line C-C'). After that, the
air flows along a path formed by the fourth thermal bonding line
134 and as a result flows into the air pillar 103 through the valve
120.
[0049] The air introduced into the air pillar 103 as mentioned
above expands the air pillar 103 and increases an inner pressure of
the air pillar 103. If the air pillar 103 is expanded, the two
inner sheets 121 are closely adhered to any one of the outer sheets
thermally bonded by the fourth thermal bonding line 134. At this
time, the pressure of air is applied toward the outer sheet to
which the two inner sheets 121 are thermally bonded, thereby
closing the valve 120. The air pressure is concentrated on a curved
region formed just below the location of the second thermal bonding
portion 152, than on a flat portion, thereby giving a primary
sealing effect.
[0050] If the inner pressure of the air pillar 103 is further
increased in this state, the air flows into the pressurization
space 160 through the second passage 125B of the second thermal
bonding portions 152. Also, the air introduced into the
pressurization space 160 presses the two inner sheets 121 in the
pressurization space 160 toward any one of the outer sheets,
thereby giving a secondary sealing effect. Here, the air pressure
is more concentrated on a curved region of the outer sheet expanded
by a thermally bonded region, such as a region below the second
thermal bonding line 132 and above the second thermal bonding
portion 152, than on a flat portion of the expanded outer sheet
105.
[0051] It is because the curved region has a larger surface area
than the flat portion, so pressure is more greatly applied to the
curved region. Thus, sealing is more excellent as there are more
curved regions. In this principle, as the valve 120 is expanded by
air, the second thermal bonding portion 152 may further improve a
sealing property by forming more curved regions where air pressure
is concentrated.
[0052] In other words, in the air bag 100, before the air filled in
the air pillar 103 passes through the second passage 125B as the
second thermal bonding portion 152 is formed, namely below the
second thermal bonding portion 152, the two inner sheets 121 are
primarily pressed to any one of the outer sheets for sealing, and
then, after the air passes through the second passage 125B, the two
inner sheets 121 are secondarily pressed to any one of the outer
sheets in the pressurization space 160 for sealing, thereby giving
a double sealing structure. According to the double sealing
structure, it is possible to minimize leakage of air filled in the
air pillar 103.
[0053] FIG. 6 is a perspective view showing another embodiment of
an air bag disclosed herein.
[0054] In the air bag 100 of this embodiment, a heat resistance ink
140 is continuously applied to an end of an inner side of any one
of the two inner sheets 121 in a length direction of the inner
sheet. Also, the air bag 100 further includes a first thermal
bonding portion 151 that ensures smooth widening of the valve 120.
Here, the length direction of the inner sheet means a direction
perpendicular to the third thermal bonding line 133, namely a
direction perpendicular to a length direction of the air pillar
103.
[0055] In detail, the first thermal bonding portion 151 is
discontinuously formed between the first thermal bonding line 131
and the second thermal bonding line 132 in correspondence to the
third thermal bonding line 133, and it is formed at an end of the
inner sheet coated with the heat resistance ink 140. A part of the
first thermal bonding portion 151 thermally bonds the two outer
sheets 105, and the other part of the first thermal bonding portion
151 thermally bonds the two outer sheets 105 and the two inner
sheets 121. Here, a gap between the first thermal bonding portions
151 is called "a first passage 125A".
[0056] Also, the heat resistance ink 140 is continuously applied to
an end of the inner sheets 121, and also the second thermal bonding
line 132 is formed along the heat resistance ink 140. As the second
thermal bonding line 132 is formed along the heat resistance ink
140 as mentioned above, the third thermal bonding line 133 may be
connected to any point of the second thermal bonding line 132.
Also, a gap between the third thermal lines 133 is opened due to
the heat resistance ink 140, so air may be easily injected into the
air pillar 103 formed by the third thermal bonding line 133.
[0057] A method for making the air bag of this embodiment will be
explained in more detail. The two inner sheets 121 are positioned
on one outer sheet 105, and the fourth thermal bonding line 134 is
formed such that the two inner sheets 121 are fixed to one outer
sheet 105. Then, the other outer sheet 105 is placed to cover the
two inner sheets 121. Here, the heat resistance ink 140 is located
at an inner portion of the overlapped inner sheets.
[0058] Then, an air input channel 101 is formed. The air input
channel 101 is made by forming the first thermal bonding line 131
and the second thermal bonding line 132. The first thermal bonding
line 131 is formed in parallel along a length direction of the
valve 120 just by thermally bonding the two outer sheets 105. The
second thermal bonding line 132 extends in parallel with the first
thermal bonding line 131 continuously along the heat resistance ink
140. At this time, the two inner sheets 121 are not bonded to each
other due to the heat resistance ink 140, but the outer sheet 105
is bonded to the inner sheet 121.
[0059] In this state, the third thermal bonding line 133, the first
thermal bonding portion 151 and the second thermal bonding portion
152 may be formed at the same time by molding or formed in any
order according to work conditions. The forming order may be
changed.
[0060] The third thermal bonding line 133 perpendicularly extends
with respect to the second thermal bonding line 132 to form a
sealed air pillar 103. Here, the third thermal bonding line 133
formed at a region where the inner sheet 121 is located thermally
bonds all of the two inner sheets 121 and the two outer sheets 105,
and the third thermal bonding line 133 formed at a region where the
inner sheet 121 is not located thermally bonds only the two outer
sheets. The third thermal bonding line 133 formed at a region where
the heat resistance ink 140 is located bonds only the inner sheet
121 and the outer sheet 105 due to the heat resistance ink 140 but
does not bond the inner sheets 121 with each other.
[0061] Meanwhile, the first thermal bonding portion 151 is formed
between the first thermal bonding line 131 and the second thermal
bonding line 132, namely at the air input channel 101, and the
first thermal bonding portion 151 is formed at an end of the inner
sheet 121 in correspondence to the third thermal bonding line 133,
namely at an end where the heat resistance ink 140 is applied.
Thus, a part of the first thermal bonding portion 151 located at an
inner side of the heat resistance ink 140 thermally bonds the inner
sheet 121 to the outer sheet, and the other part of the first
thermal bonding portion 151 located at an outer side of the inner
sheet 121 thermally bonds only the outer sheets 105. Here, a gap
between the first thermal bonding portions 151 is the first passage
125A.
[0062] One end of the air input channel 101 is closed, and the
other end of the air input channel 101 at an opposite side to the
air pillar 103 where the valve 120 is positioned is closed. Thus,
as air is introduced into the air pillar 103 through the valve 120,
the air pillar 103 is expanded.
[0063] FIG. 7 is a sectional view taken along the line B-B', which
illustrates expansion of the air introduction channel and widening
of the first passage by the thermal bonding portion shown in FIG.
6. If the air input channel 101 is expanded, the two inner sheets
121 are respectively bonded to the outer sheet 105 by the first
thermal bonding portion 151 to widen a gap between the two inner
sheets 121, thereby forming the first passage 125A. The air is
introduced through the first passage 125A over the second thermal
bonding line 132 into the valve 120 between the third thermal
bonding lines 133. While air is introduced through the first
passage 125A, a direction in which the first passage 125A is
expanded is identical to a direction in which the valve 120, namely
the two inner sheets 121, is widened. In other words, in this
embodiment, the first passage 125A does not form an oval shape in
which a major axis is longer than a minor axis, but is widened in a
substantially circular shape since the expanding direction of the
first thermal bonding portions 151 is identical to the widening
direction of the first passage 125A. Thus, a pressure applied to
the first passage 125A exerts a pressure to open the valve 120, so
the valve is smoothly opened by the first passage 125A.
[0064] Components that may be added to the air bag of this
embodiment will be explained in detail.
[0065] Thermal bonding points 139 are formed with intervals in a
direction perpendicular to the air pillar 103 in the middle of the
air pillar 103 in its length direction. The thermal bonding points
139 play a role of a folding line along which the air pillar 103
may be folded. At least one thermal bonding point 139 may be formed
per one air pillar. Particularly, two or three thermal bonding
points 139 may be formed per one air pillar 103.
[0066] In a general air bag 10, a folding line 17 is formed in a
width direction of the air pillar 13. The folding line 17 does not
entirely close the air pillar 13 such that air may flow in the air
pillar 13, but the folding line 17 reduces an inner space of the
air pillar 13, so the air pillar 13 may be easily folded with
respect to the folding line 17. This folding line 17 should be
positioned at a width center of the air pillar 13. If the folding
line 17 leans in one direction, an inner space in an opposite side
is wider, so it is difficult to fold the air pillar 13.
[0067] However, if the air bag 10 is pushed from its accurate
location when the folding line 17 is formed, the folding line 17
may be frequently biased in one side, not located at a width center
of the air pillar 13.
[0068] In accordance with this embodiment, at least one thermal
bonding point 139 bonded to have a substantially circular shape is
formed per one air pillar 103 of the air bag 100. Two thermal
bonding points 139 may be formed at regular intervals per one air
pillar 103. The thermal bonding points 139 are formed in the air
pillars 103 without occupying a large area, differently from a
general folding line 17. Thus, even when the air bag 100 is pushed
while the thermal bonding points 139 are formed, the inner space of
the air pillar 103 may be more uniformly reduced. In this way, the
air pillar 103 may be easily folded due to the thermal bonding
points 139.
[0069] FIG. 8 is a plan view showing another embodiment of an air
bag disclosed herein, to which a cock is mounted. The air input
channel 101 explained above has one closed side and the other open
side, so an air injector is inserted into the other open side to
inject air therein. However, as shown in FIG. 8, it is also
possible that both ends of the air input channel 101 are closed,
but a cock 170 is formed in any one of the outer sheets 105
corresponding to the air input channel 101. In this case, an air
injector is closely adhered to the cock 170 and then injects air
into the air input channel 101.
INDUSTRIAL APPLICABILITY
[0070] The air bag disclosed herein ensures an excellent sealing
property and high productivity, so it may be used for packaging
various articles.
* * * * *