JP2009149215A - Gas generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas generator easy in assembling work. <P>SOLUTION: This gas generator is provided with a housing 11, an ignition means, a gas generating agent and a cylindrical filter 20. The ignition means includes an ignition device 40 having an igniter 40a and an inflammation explosive 70 filled into an inflammation explosive cup member 30. An opening 65 of the inflammation explosive cup member 30 is closed by a lid 80. The gas generator can be handled as an assembly including the inflammation explosive 70, and thereby the assembling work becomes easy. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a gas generator used in an airbag system or a pedestrian protection system mounted on a motor vehicle.

  Gas generators for vehicle restraint devices such as airbag devices and pedestrian protection devices are required to have a simple internal structure from the viewpoint of weight reduction and cost reduction.

  In the gas generator shown in FIG. 1 of Patent Document 1, a tubular member 30 is disposed concentrically with the housing 11 inside the housing 11 formed by the diffuser shell 12 and the closure shell 13. The tubular member 30 has a main body portion 31 and an annular flat surface 32 formed integrally with the main body portion 31, and the igniter 40 side of the tubular member 30 is expanded in diameter.

In the gas generator of patent document 1, since the igniter 40 is accommodated in the main body part 31 of the tubular member 30, the transfer charge cannot be filled unless the tubular member 30 is attached.
JP 2005-178599 A

  It is an object of the present invention to provide a gas generator having a simple internal structure and easy to assemble, which can be used as an independent assembly in which a charge transfer agent is filled in a transfer charge cup member. To do.

The invention of claim 1 is a solution to the problem.
A housing comprising a peripheral wall having a gas discharge port, a top plate and a bottom plate, ignition means accommodated in the housing, gas generating agent ignited and combusted by the ignition means, and so as to surround the ignition means and the gas generating agent A gas generator comprising a cylindrical filter arranged;
The ignition means includes an igniter having an igniter, and a transfer charge accommodated in a transfer charge cup member that is ignited and burned by the igniter and ignites the gas generating agent,
The transfer powder cup member has a bottom portion formed with a first hole through which a combustion product from the igniter passes, a peripheral wall portion formed with a second hole group through which the combustion product of the transfer powder passes, and an opening. It has a flange part formed on the periphery,
A gas generator is provided, wherein a bottom portion of the charge transfer cup member is directly opposed to an ignition portion of the igniter, and a flange portion of the transfer charge cup member is in contact with an inner peripheral surface of the cylindrical filter. To do.

  In the present invention, the transfer charge cup member is used and the transfer charge is filled therein, so that the transfer charge cup member filled with the transfer charge can be made into one assembly. For this reason, it is not necessary to fill the transfer charge after attaching the cup member. As described above, the gas generator of the present invention increases the degree of freedom of assembly work and facilitates assembly work. In addition, since the flange portion of the charge transfer cup member positions the tubular filter, the tubular filter can be positioned by attaching the transfer charge cup member to the housing.

  The first hole and the second hole group (a plurality of holes) are preferably closed with a seal tape before operation. In the present invention, instead of the hole, it is closed before the operation, but can be opened by opening the ignition means (that is, it can communicate with the inside and outside of the gunpowder cup member). You may form the part which entered, and a part thinner than other parts. Such a fragile portion has the same effect as a hole closed with a seal tape.

  The invention according to claim 2 is characterized in that the opening portion of the transfer charge cup member has a step portion, and a lid member is attached so as not to contact the housing top plate at the step portion. A gas generator is provided.

  It is preferable to close the opening of the transfer charge cup member with a lid member for the purpose of improving the handleability as one assembly and improving the moisture resistance. The lid member may be a metal plate or a thin member such as a metal seal tape. Then, by forming a step in the opening and attaching a lid member thereto, the lid member can be prevented from coming into contact with the inner wall surface of the housing. Therefore, in particular, a sealing tape or a sealing film or sheet is used as the lid member. When used, the seal tape or the like can be prevented from being damaged.

The invention of claim 3 is another solution to the problem.
A housing comprising a peripheral wall having a gas discharge port, a top plate and a bottom plate, ignition means accommodated in the housing, gas generating agent ignited and combusted by the ignition means, and so as to surround the ignition means and the gas generating agent A gas generator comprising a cylindrical filter arranged;
The ignition means includes an igniter having an igniter, and a transfer charge accommodated in a transfer charge cup member that is ignited and burned by the igniter and ignites the gas generating agent,
The gunpowder cup member has a bottom part in which a first hole through which a combustion product from the igniter passes is formed, and a peripheral wall part in which a second hole group through which the combustion product of the gunpowder product passes is formed. And the bottom portion is directly opposed to the ignition portion of the igniter,
An opening of the explosive cup member is closed at the center of the disc-shaped lid member, and a peripheral portion of the disc-shaped lid member is in contact with the inner peripheral surface of the cylindrical filter. Provide a generator.

  In the present invention, the transfer charge cup member is used, and the transfer charge is filled therein. Therefore, the transfer charge cup member is filled with the transfer charge, and the opening is closed with a disc-shaped lid member. One assembly can be provided. For this reason, it is not necessary to fill the transfer charge after attaching the cup member. As described above, the gas generator of the present invention increases the degree of freedom of assembly work and facilitates assembly work.

  In addition, since the disc-shaped lid member that closes the opening of the transfer charge cup member positions the cylindrical filter, the opening can be closed by combining the transfer charge cup member and the disc-shaped cover member. The cylindrical filter can be positioned by attaching it to the housing in this state.

  According to a fourth aspect of the present invention, the center of the disc-shaped lid member has a stepped portion, and the stepped portion is fitted into the opening of the transfer charge cup member. Provide a bowl.

  The assembly is easily formed by fitting the step formed at the center of the disk-shaped lid member into the opening of the transfer charge cup member. Further, the cylindrical filter can be automatically positioned by disposing it in the housing in this state.

  Invention of Claim 5 has the recessed part in the bottom part of the said charge transfer cup member, The ignition part of the said igniter is accommodated in the said recessed part at any one of Claims 1-4. A gas generator is provided.

  By fitting the recess formed in the bottom of the charge transfer cup member into the ignition part, it is possible to easily attach and position the igniter to the charge transfer cup.

  According to the present invention, the explosive charge cup member in a state filled with the explosive charge can be handled as one assembly, so that the assembling work is facilitated.

(1) Gas generator of FIG. 1 FIG. 1 is a longitudinal sectional view of a gas generator of the present invention.

  The gas generator 10 is formed by welding a diffuser shell 12 that forms a peripheral wall 12b in which a top plate 12a and a gas discharge port 17 are formed, and a bottom shell 13a and a closure shell 13 that forms a peripheral wall 13b at a joint 16. An outer shell container is formed by the housing 11.

  In the joining part 16, the peripheral wall (combination of the peripheral walls 12b and 13b) of the diffuser shell 12 and the closure shell 13 is joined by laser welding or the like. In the structure of FIG. 1, there is no joint other than the joint 16.

  An upper annular slope 14 is provided at the annular contact portion between the top plate 12a and the peripheral wall 12b of the diffuser shell 12, and a lower annular slope 15 is provided at the annular contact portion between the bottom plate 13a and the peripheral wall 13b of the closure shell 13. ing.

  The gas discharge port 17 formed in the diffuser shell 12 is closed with an aluminum seal tape 56 for moisture prevention. The gas discharge ports 17 are plural having a single diameter, but may be plural having different diameters.

  A cylindrical filter 20 is disposed in the housing 11. The tubular filter 20 has elasticity in the axial direction, and both end surfaces 21 and 22 thereof are in contact with the upper annular slope 14 and the lower annular slope 15 and are assembled in the housing 11 in a state of being compressed in the axial direction. It has been found. As a result, the contact surface between the end faces 21 and 22 and the upper and lower annular slopes 14 and 15 has an enhanced effect of preventing a short path of combustion gas. The cylindrical filter 20 is a well-known one, and is substantially composed of a flat knitted wire mesh knitted in multiple layers and compressed in a mold, or a single wire wound continuously in multiple layers. Something is used.

  The cylindrical filter 20 is disposed so as to have a gap 25 between the peripheral walls 12b and 13b. Due to the action of the gap 25, the generated gas passes through the entire region of the cylindrical filter 20, so that the filtration and cooling effect of the generated gas is improved.

  A transfer charge cup member 30 is disposed in the housing 11 concentrically with the housing 11. A recess 60 is formed in the bottom surface 30 a of the transfer charge cup member 30, and a first communication hole 61 is formed in the recess 60. The first communication hole 61 is closed with a seal tape 62 before operation.

  A plurality of second communication holes 63 are formed in the circumferential wall portion 30b of the charge transfer cup member 30 at equal intervals in the circumferential direction. The second communication hole 63 is closed with a seal tape 64 before operation.

  A step 67 is formed in the opening 65 of the charge transfer cup member 30, and a flange 30c is further formed. The peripheral portion of the flange portion 30c is bent toward the housing bottom plate 13a to form an annular portion 30d. The flange portion 30 c is in contact with the housing top plate 12 a, and the outer peripheral surface of the annular portion 30 d is in contact with the inner peripheral surface of the tubular filter 20.

  The internal space of the charge transfer cup member 30 becomes the first combustion chamber 35 and is filled with a first gas generating agent 70 that becomes a transfer charge. The opening 65 is closed by adhering a lid 80 made of an aluminum sheet to the stepped portion 67.

  A protrusion 18 is formed at the central portion of the top plate 12 a of the diffuser shell 12 and is fitted into the opening 65 of the explosive charge cup member 30. Thereby, the explosive cup member 30 is positioned with respect to the diffuser shell 12. The extent of the protrusion 18 projecting to the inside of the housing 11 may be such that the transfer charge cup member 30 can be positioned.

  A gap 81 is formed between the step portion 67 and the projection portion 18 of the transfer charge cup member 30, and the lid 80 attached to the step portion 67 is not in contact with the projection portion 18. For this reason, even when a thin member is used as the lid 80, the lid 80 is not damaged.

  The igniter 40 is attached to a metal collar 72. An annular portion 74 is formed at the lower end of the collar 72 and is caulked outward in a state of being fitted into a hole formed in the central portion of the bottom plate 13 a of the closure shell 13. Reference numeral 78 denotes a sealing member for sealing a gap between the closure shell 13 and the collar 72.

  The ignition part 40 a of the igniter 40 is fitted in the recess 60 of the charge transfer cup member 30, and the collar 72 is in contact with the bottom surface 30 a of the transfer charge cup member 30. If necessary, the bottom surface 30a and the igniter 40 may be fixed with an adhesive.

  A space surrounded by the igniter 40, the charge transfer cup member 30 and the cylindrical filter 20 becomes a second combustion chamber 50 and is filled with a second gas generating agent 51. In the second gas generating agent 51 (the gas generating agent for inflating the airbag) and the first gas generating agent 70 (the transfer agent), the combustion temperature of the first gas generating agent is higher than the combustion temperature of the second gas generating agent 51. It is set to be.

  As the charge transfer agent (first gas generating agent 70), for example, a gas generating agent having a combustion temperature of 1700 to 3000 ° C. disclosed in JP-A-2005-199867 can be used in addition to known boron nitrate. As the second gas generating agent 51, for example, a gas generating agent having a combustion temperature of 1000 to 1700 ° C. disclosed in JP-A-2005-199867 can be used.

  Next, the operation when the gas generator of FIG. 1 is incorporated in an automobile airbag device will be described.

  When the automobile collides, a command from the impact sensor is received, the igniter 40 is activated, and high temperature gas or flame (combustion product) is generated from the ignition part 40a. This combustion product breaks the seal tape 62, passes through the first communication hole 61, and ignites the first gas generating agent 70 in the first combustion chamber 35. The flame and high-temperature gas (combustion product) generated from the first gas generating agent 70 further breaks the seal tape 64 and is injected into the second combustion chamber 50 from the second communication hole 63, and the second gas generating agent. 51 is ignited and burned to generate a gas as an airbag inflation medium.

  Next, a method for assembling the gas generator of FIG. 1 will be described.

  The first gas generating agent 70 is filled in the inside (first combustion chamber 35) in a state where the first communication hole 61 and the second communication hole 63 of the explosive charge cup member 30 are closed with the seal tapes 62 and 64, respectively. Thereafter, a lid 80 is attached to the stepped portion 67 to form one assembly including the explosive charge cup member 30.

  Separately, a seal tape 56 is affixed to the gas discharge port 17, and in this state, the diffuser shell 12 is placed with the top plate 12 a facing down, and an assembly including the explosive cup member 30 is placed on the protrusion 18. At this time, the opening 65 is fitted into the protrusion 18.

  Thereafter, the tubular filter 20 is disposed so as to contact the annular portion 30 d, the ignition portion 40 a is fitted in the recess 60 of the charge transfer cup member 30, and the igniter 40 is placed on the transfer charge cup member 30. In this way, each of the cylindrical filter 20, the transfer charge cup member 30 (one assembly), and the igniter 40 can be easily positioned.

  Next, the second gas generating agent 51 is filled in the gap (second combustion chamber 50) between the cylindrical filter 20, the charge transfer cup member 30 and the igniter 40. After the second gas generating agent 51 is filled, the seal member 78 is disposed and the closure shell 13 is covered. Finally, the annular portion 74 of the collar 72 is caulked to fix the igniter 40.

  Thus, since the first gas generating agent 70 is filled in the transfer powder cup member 30 and the opening 65 is closed by the lid 80, it can be handled as one assembly, so that handling becomes easy. Assembly work is facilitated.

(2) Gas Generator in FIG. 2 FIG. 2 is a longitudinal sectional view of a gas generator according to another embodiment of the present invention.

  Since the gas generator 100 is the same as the gas generator 10 of FIG. 1 except for the structure of the explosive cup member, only the different parts will be described.

  The explosive charge cup member 130 disposed in the housing 11 has a recess 60 formed in the bottom surface 130 a, and a first communication hole 61 is formed in the recess 60. The first communication hole 61 is closed with a seal tape 62 before operation.

  A plurality of second communication holes 63 are formed at equal intervals in the circumferential direction on the peripheral wall portion 130 b of the charge transfer member 130. The second communication hole 63 is closed with a seal tape 64 before operation.

  The opening 165 of the transfer charge cup member 130 is closed by a disc-like lid member 180. The disc-shaped lid member 180 has a convex portion 180 a at the center, and the convex portion 180 a is fitted into the opening 165. A seal member may be disposed at a contact portion between the opening 165 and the convex portion 180a. As described above, in the embodiment of FIG. 2, the transfer charge cup member 130 and the disc-like lid member 180 are combined to form one assembly.

  The peripheral portion of the disc-shaped lid member 180 is bent in the direction of the housing bottom plate 13a to form an annular portion 180c. The disc-shaped lid member 180 is in contact with the housing top plate 12 a, and the outer peripheral surface of the annular portion 180 c is in contact with the inner peripheral surface of the tubular filter 20.

  Although a gap 81 is formed between the convex portion 180a and the projection portion 18, the disc-shaped lid member 180 is stronger than an aluminum sheet, and therefore the gap 81 may not be provided.

  As described above, in the present embodiment, the transfer gas cup member 130 filled with the first gas generating agent 70 and the opening portion closed by the disc-like lid member 180 can be handled as one assembly. Therefore, in addition to easy handling, positioning of the parts including the one assembly is facilitated, and assembly work is facilitated.

The longitudinal cross-sectional view of the gas generator of this invention. The longitudinal cross-sectional view of the gas generator of embodiment different from FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Gas generator 11 Housing 20 Cylindrical filter 30 Transfer charge cup member 35 1st combustion chamber 40 Igniter 40a Ignition part 50 2nd combustion chamber 51 2nd gas generating agent 70 1st gas generating agent (transfer charge)
80 lids

Claims (5)

A housing comprising a peripheral wall having a gas discharge port, a top plate and a bottom plate, ignition means accommodated in the housing, gas generating agent ignited and combusted by the ignition means, and so as to surround the ignition means and the gas generating agent A gas generator comprising a cylindrical filter arranged;
The ignition means includes an igniter having an igniter, and a transfer charge accommodated in a transfer charge cup member that is ignited and burned by the igniter and ignites the gas generating agent,
The transfer powder cup member has a bottom portion formed with a first hole through which a combustion product from the igniter passes, a peripheral wall portion formed with a second hole group through which the combustion product of the transfer powder passes, and an opening. It has a flange part formed on the periphery,
The gas generator, wherein a bottom portion of the transfer powder cup member is directly opposed to an ignition portion of the igniter, and a flange portion of the transfer powder cup member is in contact with an inner peripheral surface of the cylindrical filter.   The gas generator according to claim 1, wherein an opening of the explosive charge cup member has a stepped portion, and a lid member is attached to the stepped portion so as not to contact the housing top plate. A housing comprising a peripheral wall having a gas discharge port, a top plate and a bottom plate, ignition means accommodated in the housing, gas generating agent ignited and combusted by the ignition means, and so as to surround the ignition means and the gas generating agent A gas generator comprising a cylindrical filter arranged;
The ignition means includes an igniter having an igniter, and a transfer charge accommodated in a transfer charge cup member that is ignited and burned by the igniter and ignites the gas generating agent,
The gunpowder cup member has a bottom part in which a first hole through which a combustion product from the igniter passes is formed, and a peripheral wall part in which a second hole group through which the combustion product of the gunpowder product passes is formed. And the bottom portion is directly opposed to the ignition portion of the igniter,
An opening of the explosive cup member is closed at the center of the disc-shaped lid member, and a peripheral portion of the disc-shaped lid member is in contact with the inner peripheral surface of the cylindrical filter. Generator.   The gas generator according to claim 3, wherein a central portion of the disc-shaped lid member has a stepped portion, and the stepped portion is fitted into an opening of the transfer charge cup member.   The gas generator according to any one of claims 1 to 4, wherein a bottom of the explosive cup member has a recess, and at least an ignition part of the igniter is accommodated in the recess.

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