WO2009142372A1

WO2009142372A1 - Air bag with air input coke

Info

Publication number: WO2009142372A1
Application number: PCT/KR2008/006786
Authority: WO
Inventors: Sung Jun Kim; Jun Nam Choi
Original assignee: Indis Air Corp.
Priority date: 2008-05-20
Filing date: 2008-11-18
Publication date: 2009-11-26

Abstract

An air bag includes two outer sheets, two inner sheets positioned therebetween, a heat resistance ink applied to any one of the two inner sheets to form a passage, a second thermal bonding line passing the heat resistance ink and thermally bonding the two outer and inner sheets, a first thermal bonding line formed at one side with a gap from the second thermal bonding line and thermally bonding the two outer sheets to form an air input channel between the first and second thermal bonding lines, a third thermal bonding line extending from the second thermal bonding line in the other direction to form an air pillar, and a cock mounted to one outer sheet between the first and second thermal bonding lines such that air is injected into the air input channel through the cock.

Description

Description AIR BAG WITH AIR INPUT COCK

Technical Field

[1] This disclosure relates to an air bag, and more particularly to an air bag to which air may be easily injected using an air injector. Background Art

[2] 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.

[3] In the appended drawings, Fig. 1 is a perspective view showing a general air bag,

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, and Fig. 3 is a plan view showing a valve of the air bag to which air is not yet injected.

[4] 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.

[5] Hereinafter, the general air bag is explained in detail.

[6] 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.

[7] 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.

[8] 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. The first thermal bonding line 31 bonds just the two outer sheets 15.

[9] 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.

[10] 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 due to the heat resistance inks 23.

[11] 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. Thus, 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.

[12] 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 bonded and fixed by the first thermal bonding point 41 become wider in opposite directions to open the passage 25.

[13] Meanwhile, 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.

[14] Thus, when air is injected to the air input channel 11, the air is introduced to the air pillars 13 through the passages 25, and the passages 25 are closed due to the inner pressure of the air pillars 13.

[15] A process of injecting air into the general air bag is as follows. An air injector 50 is inserted into one end of the air input channel 11, and then the air injector 50 injects a high pressure air into the air input channel 11 such that the air in the air input channel flows into the air pillars through the passages.

[16] However, as explained above, the air input channel 11 is formed with the two outer sheets by the first thermal bonding line and the second thermal bonding line, so the air injector is inserted into the air input channel in a state that one end of the air input channel is widened, so it is difficult to inject air. Also, since the outer sheets have a small thickness, and the first and second thermal bonding lines are formed adjacently, it is difficult to widen one end of the air input channel.

[17] Referring to Fig. 1 again, the general air bag has a folding line 17 in a lateral direction with respect to the width of the air pillars 13. [18] However, if the two outer sheets 15 are pushed or not correctly positioned while such a folding line 17 is formed, the folding line 17 may be contacted or crossed with any one third thermal bonding line 33 as shown in Fig. 3. If the folding line 17 is pushed and biased toward any one third thermal bonding line 33, the air pillar is not easily folded at the folding line 17. If the air pillar is folded with an excessive force in this state, the inner pressure of the air pillar is abruptly increased, so air may be easily leaked.

Disclosure of Invention Technical Problem

[19] The disclosure is designed to solve the above problems, and therefore the disclosure is directed to providing an air bag having a cock such that air may be easily injected therein using an air injector. Technical Solution

[20] In one aspect, there is provided an air bag, which includes two outer sheets, two inner sheets positioned between the outer sheets, at least one heat resistance ink applied to any one of facing surfaces of the two inner sheets to form a passage, a second thermal bonding line formed to pass the heat resistance ink and thermally bonding the two outer sheets and the two inner sheets, a first thermal bonding line formed with a gap from the second thermal bonding line at one side with respect to the second thermal bonding line and thermally bonding the two outer sheets to form an air input channel between the first thermal bonding line and the second thermal bonding line, a third thermal bonding line extending from the second thermal bonding line in the other direction with respect to the second thermal bonding line to form an air pillar, and a cock mounted to any one of the outer sheets between the first thermal bonding line and the second thermal bonding line that form the air input channel such that air is injected into the air input channel through the cock.

[21] Also, in one embodiment, the cock may have a rim thermally bonded and fixed to any one of the outer sheets such that air is injected into the air input channel through an air hole formed in the cock when an air injector is closely adhered to an outer side of the cock and injects air.

[22] Also, in one embodiment, there may be formed a plurality of third thermal bonding lines in parallel, and two third thermal bonding lines located at outer sides may extend to close both ends of the air input channel.

[23] Also, in one embodiment, a thermal bonding portion may be formed in the air input channel at a side of the passage to bond the two inner sheets and the two outer sheets.

[24] Also, in one embodiment, the two inner sheets may be inserted into the air input channel by a length of 0.1 to 5 mm. [25] Also, in one embodiment, the two inner sheets located in the air input channel may be bonded to the outer sheets by means of first thermal bonding points, respectively.

[26] Also, in one embodiment, the thermal bonding portion may be formed on an extension line of the third thermal bonding line along a length of the air input channel alternately with the passage.

[27] Also, in one embodiment, multi points may be formed in a direction of crossing the third thermal bonding line to thermally bond the plurality of outer sheets, and at least two multi points may be formed between the third thermal bonding lines.

[28] Also, in one embodiment, the two inner sheets located in the air pillar with respect to the second thermal bonding line may be thermally bonded to any one of the two outer sheets in a dot pattern.

[29] Also, in one embodiment, the two inner sheets may have different thicknesses from each other.

[30] Also, in one embodiment, the thermal bonding portion may extend from the second thermal bonding line without contacting the first thermal bonding line.

[31] Also, in one embodiment, the thermal bonding portion may have a triangular structure.

[32] Also, in one embodiment, the two inner sheets located in the air pillar may be not thermally bonded to the outer sheets but thermally bonded with each other such that the passage is closed due to an inner pressure of the air pillar after air is completely injected into the air pillar through the passage.

[33] Also, in one embodiment, the cock may include a cock body fixed to any one of the outer sheets and having air holes at a center area thereof, and a rubber film fixed to an inside of the cock body located in the air input channel to cover the air holes, wherein the rubber film is elastically transformed due to an inner pressure to open the air holes, and the rubber film is recovered to close the plurality of air holes when the air pressure is released.

[34] Also, in one embodiment, the multi points may be formed at regular intervals.

Advantageous Effects

[35] As described above, in the air bag disclosed herein, if air is injected in a state that an air injector is closely adhered to a cock exposed outward, the air is introduced into air pillars through an air input channel and a passage, so the air pillars are expanded. If the air is completely injected, the air injector closely adhered to the cock may be easily removed. Thus, it is possible to overcome any trouble caused by a general air bag in which air is injected while inputting an air injector to a widened end of an air input channel and then the air injector is drawn out after the air is completely injected.

[36] Also, in the air bag disclosed herein, a folding portion of the air pillars are configured as multi points to compensate for any error during a work, thereby ensuring a fast work and decreasing an inferiority rate. Brief Description of Drawings

[37] 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:

[38] Fig. 1 is a perspective view showing a general air bag;

[39] 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 ;

[40] Fig. 3 is a plan view showing the valve when air is not injected to the air bag;

[41] Fig. 4 is a perspective view showing one embodiment of an air bag disclosed herein;

[42] Fig. 5 is a sectional view showing a cock of Fig. 4;

[43] Fig. 6 is a front view showing the cock of Fig. 5;

[44] Fig. 7 is a sectional view illustrating an operation of the cock of Fig. 4;

[45] Fig. 8 is a plan view showing the air bag of Fig. 4, to which air is not yet injected;

[46] Fig. 9 is a plan view showing an air bag having wider air pillars than those of the air bag of Fig. 8;

[47] Fig. 10 is a sectional view taken along the line B-B', which illustrates that an air input channel is expanded and a passage is widened due to a thermal bonding portion of Fig. 8;

[48] Fig. 11 is a perspective view showing another embodiment of an air bag disclosed herein;

[49] Fig. 12 is a vertical sectional view taken along the line C-C, which illustrates a valve of the air bag shown in Fig. 11 ;

[50] Fig. 13 is a plan view showing a valve in a state that air is not yet injected to an air bag;

[51] Fig. 14 is a cross-sectional view of an air pillar, which illustrates another example of a valve in a state that two inner sheets are not contacted to any one of outer sheets but floating at a middle of a cross-sectional surface of an air pillar;

[52] Fig. 15 is an exploded sectional view showing a different type of cock disclosed herein;

[53] Fig. 16 is a front view showing the cock of Fig. 15; and

[54] Fig. 17 is a schematic view illustrating a process of injecting an air into the cock of

Fig. 15.

[55] * Reference Numerals of Essential Parts in the Drawings *

[56] 100, 100' air bag 101 : air input channel

[57] 103: air pillar 105: outer sheet [58] 120: valve 121: inner sheet

[59] 123: heat resistance ink 125: passage

[60] 131-133: thermal bonding line 134: thermal bonding portion

[61] 141, 142: thermal bonding point 143: multi point

[62] 150: cock 151: cock body

[63] 153: coupling hole 155: air hole

[64] 157: rubber film 159: latch

[65] 160: air injector

Best Mode for Carrying out the Invention

[66] 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.

[67] [First Embodiment]

[68] Fig. 4 is a perspective view showing one embodiment of an air bag disclosed herein,

Fig. 5 is a sectional view showing a cock of Fig. 4, Fig. 6 is a front view showing the cock of Fig. 5, and Fig. 7 is a sectional view illustrating an operation of the cock of Fig. 4.

[69] Fig. 8 is a plan view showing the air bag of Fig. 4, to which air is not yet injected,

Fig. 9 is a plan view showing an air bag having wider air pillars than those of the air bag of Fig. 8, and Fig. 10 is a sectional view taken along the line B-B', which illustrates that an air input channel is expanded and a passage is widened due to a thermal bonding portion of Fig. 8.

[70] As shown in Fig. 4, an air bag 100 of the first embodiment includes two outer sheets

105, two inner sheets 121, a heat resistance ink 123, a valve 120, a first thermal bonding line 131, a second thermal bonding line 132, a third thermal bonding line 133, a first thermal bonding point 141 and a second thermal bonding point 142. An air input channel 101 may have a relatively greater width than an air input channel 11 (see Figs. 1 to 3) of a general air bag.

[71] The air input channel 101 has both ends closed by the third thermal bonding lines

133 formed at both ends of the air bag. A cock 150 is mounted to one side of the air input channel 101. Thus, after an air injector 160 is closely adhered to the cock 150 and injects air, the air flows into the air input channel 101 through the cock 150.

[72] As shown in Figs. 5 to 7, the cock 150 is fixed to any one of the outer sheets 105 where the air input channel 101 is formed, and a plurality of air holes 155 are formed in the center of the cock 150.

[73] In more detail, the cock 150 has a disk shape, and any one of the outer sheets 105 is thermally bonded and fixed to a rim of the cock 150. The plurality of air holes 155 are formed in the cock 150.

[74] Thus, if the air injector 160 is closely adhered to an outer side of the cock 150 and injects air with high pressure, the air is injected into the air input channel 101 through the air holes 155, and then injected into air pillars 103 through a passage 125 from the air input channel 101.

[75] Meanwhile, a thermal bonding portion 134 is formed in the air input channel 101, and the thermal bonding portion 134 is formed at both sides of the passage 125 formed by the heat resistance ink 123. The thermal bonding portion 134 thermally bonds the two inner sheets 121 and the two outer sheets 105 located in the air input channel 101.

[76] In more detail, the thermal bonding portion 134 is formed perpendicularly from the second thermal bonding line 132 toward the air input channel 101. At this time, the thermal bonding portion 134 has a length that allows thermal bonding between the inner sheets 121 and the outer sheets 105 located in the air input channel 101, and the thermal bonding portion 134 is not contacted with the first thermal bonding line 131. Also, the thermal bonding portion 134 is formed together while the third thermal bonding line 133 is formed, and it is positioned on an extension line of the third thermal bonding line 133.

[77] Meanwhile, as shown in Figs. 8 and 9, the air bag 100 may have air pillars 103 whose width may be relatively smaller or relatively greater. In case the air pillars 103 have a small width, one passage 125 may be positioned for each air pillar 103. And, in case the air pillars 103 have a great width, a plurality of passages 125 may be formed for each air pillar 103.

[78] The thermal bonding portions 134 are formed at both sides of the passages to which the heat resistance ink 123 is applied, namely alternately with the passages 125.

[79] If air is injected to the air bag 100 having the thermal bonding portions 134, the air input channel 11 is expanded as shown in Fig. 2. However, as shown in Fig. 10, since the thermal bonding portions 134 are formed in the air input channel 101 alternately with the passages 125, an expanding direction of the passages 125 is identical to an expanding direction of the air input channel 101 between the thermal bonding portions 134. Here, each inner sheet 121 and each outer sheet 105 are thermally bonded by the first thermal bonding point 141, so the passage 125 is easily widened along the expanding direction of the air input channel 101.

[80] In other words, since the expansion between the thermal bonding portions 134 in the air input channel 101 is made in the same direction as the expansion of the passage 125 to which the heat resistance ink 123 is applied, the air pressure is uniformly applied in a direction of widening the passage, so the passage 125 is easily widened.

[81] In a general air bag 10, an expanding direction of an air input channel 11 is per- pendicular to an expanding direction of a passage 25. Thus, air pressure is not uniformly applied, and the passage 25 is widened while forming a long oval shape in which a major axis is relatively longer than a minor axis. However, in the air bag of this embodiment, the expanding direction between the thermal bonding portions 134 is identical to a widening direction of the passage 125, so the passage 125 is widened while forming a substantially circular shape.

[82] The thermal bonding portion 134 may have a straight form, but it may also have a triangular structure as shown in Figs. 8 and 9.

[83] In the air bag of this embodiment, multi points 143 are formed in one row in a direction perpendicular to the third thermal bonding line 133. The multi points 143 are formed in a direction perpendicular to the air pillars 103 at regular intervals in the middle of the air pillars 103 in a length direction thereof. The multi points 143 allow the air pillars 103 to be folded, and at least two multi points 143 are formed per one air pillar 103. In this embodiment, intervals between the multi points 143 are constant.

[84] Referring to Fig. 3 again, in the general air bag 10, the folding line 17 is formed in a width direction of air pillars 13 as explained above, so the air pillars 13 may be easily folded with respect to the folding line 17. The folding line 17 does not entirely close the air pillar 13 such that air may flow in the air pillar 13. The folding line 17 reduces an inner space of the air pillar 13. If the two outer sheets 15 are pushed or positioned at inaccurate location when the folding line 17 is formed, the folding line 17 may be contacted or crossed with any one third thermal bonding line 33 as shown in Fig. 3.

[85] Thus, the 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 becomes wider, and it is difficult to fold the air pillar 13. 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. As a result, the air pillar 13 may not be easily folded along the folding line 17.

[86] However, in this embodiment, intervals of the multi points 143 are kept uniformly such that two or three multi points 143 may be formed in one air pillar 103. Thus, even when the air bag 100 is pushed while the multi points 143 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 with respect to the multi points 143. Also, since the multi points 143 thermally bond the outer sheets with a smaller region, air may be smoothly injected into the air pillar 103.

[87] [Second Embodiment]

[88] Fig. 11 is a perspective view showing another embodiment of an air bag disclosed herein, Fig. 12 is a vertical sectional view taken along the line C-C, which illustrates a valve of the air bag shown in Fig. 11, Fig. 13 is a plan view showing a valve in a state that air is not yet injected to an air bag, and Fig. 14 is a cross-sectional view of an air pillar, which illustrates another example of a valve in a state that the two inner sheets are not contacted to any one of outer sheets but floating at a middle of a cross-sectional surface of an air pillar.

[89] As shown in Fig. 11, an air bag 100' has a rectangular structure, and an air input channel 101 is formed along one side of the air bag 100'. Also, a plurality of air pillars 103 are formed perpendicularly to the air input channel 101. A plurality of valves 120 connect the air input channel 101 to the air pillars 103, so air supplied through the air input channel 101 is introduced to each air pillar 103 through the valves 120. If the air is filled in the air pillar 103, an inner pressure is generated to press the valve 120. Thus, the air pillar 103 is sealed such that the air in the air pillar 103 does not go out through the valve 120.

[90] Hereinafter, the valve of the air bag disclosed above is explained in more detail.

[91] As shown in Figs. 11 to 13, two inner sheets 121 are positioned inside two outer sheets 105, and a first thermal bonding line 131 thermally bonds the two outer sheets 105. A second thermal bonding line 132 thermally bonds the two outer sheets 105 and the two inner sheets 121 to form an air input channel 101. Here, a heat resistance ink 123 is applied to any one of facing surfaces of the two inner sheets 121 to form a passage 125.

[92] Also, third thermal bonding lines 133 are formed perpendicularly from the second thermal bonding line 132 alternately with the passages 125, thereby forming a plurality of air pillars 103.

[93] In addition, thermal bonding portions 134 are formed in the air input channel 101 alternately with the passages 125. The thermal bonding portions 134 guide the air in the air input channel 101 toward the passages 125 and thus allow the passages 125 to be easily widened. The thermal bonding portions 134 thermal bond the two outer sheets 105 and the two inner sheets 121, and they are not contacted with the first thermal bonding line 131. Here, the thermal bonding portions 134 are formed together while the third thermal bonding lines 133 are formed, and they correspond to extension lines of the third thermal bonding lines 133. The principle by which the thermal bonding portions facilitate easily widening of the passages is already explained in the first embodiment, so it is not explained in detail again.

[94] The length of the two inner sheets 121 extending into the air input channel 101 is about 0.1 to 5 mm, and a plurality of second thermal bonding points 142 are formed in the air pillars 103 to bond the two inner sheets 121 to any one of the outer sheets.

[95] Hereinafter, a process of making the air bag configured as above is explained in detail.

[96] One outer sheet 105 and two inner sheets 121 are disposed, and two thermal bonding points 142 are formed at locations corresponding to the air pillars 103. As the second thermal bonding points 142 are formed, the two inner sheets 121 and one outer sheet 105 are thermally bonded due to the second thermal bonding points 142. In this state, the other outer sheet 105 is placed to cover them, and then the first, second and third thermal bonding lines 131, 132, 133, the thermal bonding portions 134 and the multi points 143 are formed.

[97] In more detail, the first thermal bonding line 131 and the second thermal bonding line 132 are formed to configure the air input channel 101. The second thermal bonding line 132 is formed while passing the heat resistance ink 123 along the inner sheets 121, and the first thermal bonding line 131 is formed in parallel with the second thermal bonding line 132. Here, the first thermal bonding line 131 bonds only the two outer sheets 105. Thus, if air is injected between the first thermal bonding line 131 and the second thermal bonding line 132, air passes the second thermal bonding line 132 through the passage 125 formed by the heat resistance ink 123.

[98] The length of the inner sheet 121 extending into the air input channel 101 may be about 0.1 to 5 mm. If the length of the inner sheet 121 extending into the air input channel 101 is less than 0.1 mm, the second thermal bonding line 132 may be deviated from the inner sheet 121 when the second thermal bonding line 132 bonds the outer sheet 105 and the inner sheet 121, which may cause inferiority. Also, if the length exceeds 5 mm, an amount of material for the inner sheet 121 is excessively consumed more than required, which may cause increase of production costs. In addition, if the inner sheet 121 is inserted into the air input channel 101 too much, the passage 125 may be closed while air is injected. If the length of the inner sheet 121 is in the range from about 0.1 to about 5 mm, the amount of material for the inner sheet 121 may be minimized while preventing any inferiority.

[99] Meanwhile, the third thermal bonding lines 133 are perpendicularly formed from the second thermal bonding line 132 to form the air pillars 103, and the third thermal bonding lines 133 are formed alternately with locations where the heat resistance ink 123 is applied.

[100] At locations where the third thermal bonding lines 133 meet the second thermal bonding line 132, the thermal bonding portions 134 are formed in the air input channel 101. At this time, the thermal bonding portions 134 do not meet the first thermal bonding line 131. The thermal bonding portions 134 are located on extension lines of the third thermal bonding lines 133, and the thermal bonding portions 134 may be formed while the third thermal bonding lines 133 are formed.

[101] As shown in Fig. 11, the thermal bonding portion 134 has a triangular shape so that air introduced into the air input channel 101 may be guided toward the passage 125. The thermal bonding portions 134 may be formed alternately with the passages 125. [102] A cock 150 identical to that of the first embodiment is mounted to one side of the air input channel 101, and both ends of the air input channel 101 are closed by the third thermal bonding lines 133.

[103] Hereinafter, an air flow while air is injected to the air input channel 101 is explained.

[104] If air is injected to the air input channel 101, the air input channel 101 is expanded. If the air input channel 101 is expanded as mentioned above, regions not coated with the heat resistance ink 123 along the second thermal bonding line 132 are widened to form passages 125. Since the thermal bonding portion 134 is formed with a triangular shape to guide introduction of air, the passage 125 may be more easily widened. The air passing through the passage 125 widened as mentioned above is introduced into the air pillar 103 to expand the air pillar 103.

[105] If the air pillar 103 is expanded to increase an inner pressure as mentioned above, the two inner sheets 121 bonded to the outer sheet 105 by the second thermal bonding point 142 are resultantly pressed toward the outer sheet 105 to close the passage 125, namely the valve 120, thereby preventing the air from flowing out through the passage 125.

[106] In the valve 120 configured as mentioned above, the two inner sheets 121 may have different thicknesses. Among the two inner sheets 121 bonded to any one of the outer sheets by the second thermal bonding line 132, an inner sheet located in an inner side may have a smaller thickness, and the other inner sheet may have a relatively greater thickness, in order to improve sealing. This effect is obtained due to the fact that the two inner sheets have different thicknesses. Thus, even when an inner sheet located in an inner side has a greater thickness than an inner sheet located in an outer side, the sealing property is also improved.

[107] Multi points 143 are also formed in the air pillars 103 of the air bag 100 according to the second embodiment, configured as above.

[108] Intervals of the multi points 143 are kept uniformly such that two or three multi points 143 may be formed in one air pillar 103. Thus, even when the air bag 100 is pushed while the multi points 143 are formed, the inner space of the air pillar 103 may be more uniformly reduced. Thus, the air pillar 103 may be easily folded due to the multi points 143.

[109] In addition, since at least two multi points 143 are formed per each air pillar 103 to thermally bond the outer sheets 105 and do not take a line structure like the folding line 17 of a general air bag, air is easily filled in the air pillar 103.

[110] Although it has been illustrated that the two inner sheets 121 located toward the air pillar 103 with respect to the second thermal bonding line 132 are bonded to any one of the outer sheets 105 by the second thermal bonding point 142, the two inner sheets 121 may not be bonded to any one of the outer sheets 105 as shown in Fig. 14. It is also possible that the two inner sheets 121 are thermally bonded to each other such that the two inner sheets 121 close the passage 125 due to an inner pressure of the air pillar if air is completely injected into the air pillar 103 through the passage 125.

[I l l] In addition, although it has been illustrated in the first and second embodiments that both ends of the air input channel 101 are closed by extending the third thermal bonding lines 133, it is just one example, and another thermal bonding line may be formed to close both ends of the air input channel 101. Alternatively, both ends of the air input channel 101 may not be closed by thermal bonding, but both ends of the air input channel 101 may be closed using nippers such that air is injected while air discharge is intercepted, and then the nippers may be released such that air in the air input channel is discharged.

[112] Fig. 15 is an exploded sectional view showing a different type of cock disclosed herein, Fig. 16 is a front view showing the cock of Fig. 15, and Fig. 17 is a schematic view illustrating a process of injecting an air into the cock of Fig. 15.

[113] As shown in Figs. 15 to 17, the cock 150 includes a cock body 151 fixed to any one of the outer sheets 105 that form the air input channel 101 and having a plurality of air holes 155 at a center area thereof, and a rubber film 157 fixed to an inner side of the cock body 151, namely located in the air input channel 101, to cover the air holes 155.

[114] In more detail, the cock body 151 has a disk structure, and any one of the outer sheets 105 is thermally bonded and fixed to a rim of the cock body 151. Also, a coupling hole 153 is formed at the center of the cock body 151, and the plurality of air holes 155 are formed around the coupling hole 153. In addition, the rubber film 157 has a latch 159 protruding from its center, and the latch 159 is inserted into the coupling hole 153. If the latch 159 is inserted and coupled into the coupling hole 153, the rubber film 157 covers the plurality of air holes 155. Thus, if an air injector 160 is closely adhered to an outer side of the cock body 151 and injects air with high pressure, the rubber film 157 covering the air holes 155 is elastically transformed into the air input channel 101 such that the air is injected into the air input channel 101 through the air holes 155. Meanwhile, if the air injection is completed and thus the air injector 160 is separated from the cock body 151, the rubber film 157 is recovered to close the air holes 155, thereby preventing the air filled in the air input channel 101 from being discharged.

[115] Since the cock 150 prevents the air from being discharged from the air input channel 101 as mentioned above, the air input channel 101 maintains an expanded state. Industrial Applicability

[116] The air bag disclosed herein ensures easy injection of air and high productivity, so it may be used for packaging various articles.

Claims

[1] An air bag, comprising: two outer sheets; two inner sheets positioned between the outer sheets; at least one heat resistance ink applied to any one of facing surfaces of the two inner sheets to form a passage; a second thermal bonding line formed to pass the heat resistance ink and thermally bonding the two outer sheets and the two inner sheets; a first thermal bonding line formed with a gap from the second thermal bonding line at one side with respect to the second thermal bonding line and thermally bonding the two outer sheets to form an air input channel between the first thermal bonding line and the second thermal bonding line; a third thermal bonding line extending from the second thermal bonding line in the other direction with respect to the second thermal bonding line to form an air pillar; and a cock mounted to any one of the outer sheets between the first thermal bonding line and the second thermal bonding line that form the air input channel such that air is injected into the air input channel through the cock. [2] The air bag according to claim 1, wherein the cock has a rim thermally bonded and fixed to any one of the outer sheets such that air is injected into the air input channel through an air hole formed in the cock when an air injector is closely adhered to an outer side of the cock and injects air. [3] The air bag according to claim 1 or 2, wherein there are formed a plurality of third thermal bonding lines in parallel, and two third thermal bonding lines located at outer sides extend to close both ends of the air input channel. [4] The air bag according to claim 1, wherein a thermal bonding portion is formed in the air input channel at a side of the passage to bond the two inner sheets and the two outer sheets. [5] The air bag according to claim 1, wherein the two inner sheets are inserted into the air input channel by a length of 0.1 to 5 mm. [6] The air bag according to claim 1, wherein the two inner sheets located in the air input channel are bonded to the outer sheets by means of first thermal bonding points, respectively. [7] The air bag according to claim 4, wherein the thermal bonding portion is formed on an extension line of the third thermal bonding line along a length of the air input channel alternately with the passage. [8] The air bag according to claim 1, wherein multi points are formed in a direction of crossing the third thermal bonding line to thermally bond the plurality of outer sheets, and at least two multi points are formed between the third thermal bonding lines. [9] The air bag according to claim 1, wherein the two inner sheets located in the air pillar with respect to the second thermal bonding line are thermally bonded to any one of the two outer sheets in a dot pattern. [10] The air bag according to claim 1, wherein the two inner sheets have different thicknesses from each other. [11] The air bag according to claim 4, wherein the thermal bonding portion extends from the second thermal bonding line without contacting the first thermal bonding line. [12] The air bag according to claim 4 or 11, wherein the thermal bonding portion has a triangular structure. [13] The air bag according to claim 1, wherein the two inner sheets located in the air pillar are not thermally bonded to the outer sheets but thermally bonded with each other such that the passage is closed due to an inner pressure of the air pillar after air is completely injected into the air pillar through the passage. [14] The air bag according to claim 1, wherein the cock includes: a cock body fixed to any one of the outer sheets and having air holes at a center area thereof; and a rubber film fixed to an inside of the cock body located in the air input channel to cover the air holes, wherein the rubber film is elastically transformed due to an inner pressure to open the air holes, and the rubber film is recovered to close the plurality of air holes when the air pressure is released. [15] The air bag according to claim 8, wherein the multi points are formed at regular intervals.