JP5545703B2 - Gas generator - Google Patents

Description

  The present invention relates to a gas generator incorporated in an airbag device as an occupant protection device mounted on an automobile or the like, and more particularly to a gas generator having a long cylindrical outer shape.

  2. Description of the Related Art Conventionally, airbag devices, which are occupant protection devices, have been widely used from the viewpoint of protecting occupants such as automobiles. An airbag device is installed in a vehicle or the like for the purpose of protecting an occupant from an impact caused by the collision of a vehicle or the like, and is an airbag that is deployed by instantly inflating and deploying the airbag at the time of a vehicle or the like collision. It is intended to catch the passenger's body. The gas generator is a device that is incorporated in the airbag device and inflates and deploys the airbag by instantaneously generating gas when a vehicle or the like collides.

  Gas generators of various configurations exist based on specifications such as installation positions and outputs with respect to vehicles and the like. One of them is a gas generator having a structure called “cylinder type”. The cylinder type gas generator has a long cylindrical shape, and is suitably incorporated in a side airbag device, a passenger seat airbag device, a curtain airbag device, a knee airbag device, or the like. As a gas generator having a long cylindrical outer shape, there is a so-called T-shaped gas generator other than the cylinder type gas generator.

  As documents disclosing the specific structure of the cylinder type gas generator described above, for example, Japanese Patent Application Laid-Open No. 2005-313812 (Patent Document 1), Japanese Patent Application Laid-Open No. 11-78766 (Patent Document 2), and Japanese Patent Application Laid-Open No. 2002-2002. No. 166818 (Patent Document 3). In the cylinder type gas generators disclosed in Patent Documents 1 to 3, an igniter and a charge transfer agent are disposed at one end in the axial direction of a long cylindrical housing, and gas is generated at a substantially central portion in the axial direction. A working gas generation chamber is provided in which a working gas is generated by burning the gas generating agent and the gas generating agent is combusted, and a filter chamber in which the filter is housed and a gas outlet are provided at the other end in the axial direction. Yes.

  In the cylinder type gas generator having the above configuration, the flame generated by the operation of the igniter is transmitted to the gas generating agent through the combustion of the charge transfer agent, whereby the gas generating agent burns and the high-temperature and high-pressure working gas is burned. Is generated in the working gas generation chamber, and the generated high-temperature and high-pressure working gas flows from the working gas generation chamber into the filter chamber along the axial direction of the housing, passes through the filter, and passes from the gas outlet to the outside of the housing. Is ejected. The working gas ejected from the gas ejection port is then used for inflation and deployment of the airbag.

  Among these, Patent Document 3 discloses a cylinder type gas generator in which a bottomed cylindrical partition member is arranged in a working gas generation chamber (see particularly FIG. 3 of Patent Document 3). In the cylinder type gas generator in which the partition member is disposed in the working gas generation chamber, the gas generating agent is accommodated in the working gas generation chamber in the portion excluding the hollow portion of the partition member, and is ignited by the ignition means. The generated gas generating agent sequentially burns from the ignition means side to generate a working gas, and the generated working gas quickly flows into the hollow portion of the partition member through the communication hole provided in the partition member. It will move to the filter chamber. Therefore, by adopting this configuration, it is possible to prevent the unburned gas generating agent from becoming the flow resistance of the working gas, and to obtain a cylinder type gas generator having excellent output characteristics.

JP 2005-313812 A Japanese Patent Laid-Open No. 11-78766 JP 2002-166818 A

  However, when the configuration as disclosed in Patent Documents 1 to 3 described above is employed, a fragile seal member such as an O-ring or a seal tape is accurately placed at a predetermined position in the assembly process of the cylinder type gas generator. There is a problem that it is necessary to assemble, the handling becomes complicated, and the manufacturing cost increases. Further, in the cylinder type gas generator, a cushion material for preventing crushing due to vibration of the gas generating agent and a partition member as disclosed in Patent Document 3 may be accommodated in the working gas generation chamber. When assembling these members to the housing, the handling thereof becomes complicated, resulting in an increase in manufacturing cost. Furthermore, filling a cylinder-type gas generator in the middle of assembly with a charge transfer agent or gas generating agent that requires a great deal of care because it reacts sensitively to static electricity and fire involves considerable difficulty. there were.

  Therefore, the present invention has been made to solve the above-mentioned problems, and the sealing process for preventing the gas generating agent from absorbing moisture is facilitated, and the workability during assembly is greatly improved. As a result, an object of the present invention is to provide a gas generator capable of reducing the manufacturing cost.

The gas generator based on this invention is provided with the housing, the ignition means, the partition member, the division member, and the crushing prevention member. The housing is formed of a long cylindrical member whose both ends in the axial direction are closed, and is generated in a working gas generation chamber in which a working gas is generated by burning a gas generating agent, and in the working gas generation chamber. And a filter chamber containing a filter through which the working gas passes. The ignition means generates a flame for burning the gas generating agent, and is arranged at one end of the housing in the axial direction. The partition member is located inside the housing, and partitions a space inside the housing into the working gas generation chamber and the filter chamber in the axial direction. The partition member partitions the working gas generation chamber. The crush prevention member is for preventing crushing of the gas generating agent due to vibration. The filter chamber is located on the other end side of the housing with respect to the working gas generation chamber, and the working gas that has passed through the filter is ejected to the outside of the housing to define the filter chamber. For this purpose, a plurality of gas outlets are provided. The housing further includes an ignition chamber in which the ignition means is disposed, and the ignition means includes an igniter including an igniter that generates a flame by burning, and a flame generated in the igniter. For transferring the gas to the gas generating agent. A first sealed container having a sealed storage space is disposed in the working gas generation chamber, and the gas generating agent, the partition member, and the crushing are disposed in the storage space of the first sealed container. A prevention member is disposed. The partition member is configured by a bottomed cylindrical member having a hollow portion disposed coaxially with the housing, and from the end of the first sealed container on the partition member side of the housing. A cylindrical portion extending along the axial direction and a bottom portion that closes an end portion of the cylindrical portion on the ignition means side are included. Among these, the said bottom part is located in the said partition member side rather than the edge part by the side of the said ignition means of the said 1st airtight container. The gas generating agent is accommodated in the accommodating space of the first sealed container in a portion excluding the hollow portion of the partition member. The aforementioned cylindrical portion, the upper SL and a gas generating agent space and the hollow section which is accommodated a plurality of first communicating hole is provided which communicates with the central portion of the partition member, and the hollow portion A second communication hole for communicating with the filter chamber is provided. In the ignition chamber, a second sealed container having a sealed housing space is disposed, and the transfer charge is disposed in the housing space of the second sealed container. The second sealed container is composed of a member that is melted or ruptured by a flame generated by burning the ignition powder, and the first sealed container is a heat particle generated by burning the charge powder. It is composed of a member that melts or ruptures. The first sealed container and the second sealed container are positioned opposite to each other in the axial direction over the entire area in the radial direction of the space inside the housing.
In the gas generator according to the present invention, it is preferable that the first sealed container and the second sealed container are in contact with each other.

  In the gas generator according to the present invention, it is preferable that the first closed container is disposed in the working gas generation chamber by being press-fitted and fixed inside the housing.

  In the gas generator according to the present invention, it is preferable that the crushing prevention member is disposed at an end portion on the ignition means side in the housing space of the first sealed container.

  In the gas generator according to the present invention, it is preferable that the second sealed container is disposed in the ignition chamber by being press-fitted and fixed inside the housing.

  In the gas generator according to the present invention, the filter preferably has a hollow communication portion extending along the axial direction of the housing, and the hollow communication portion is the working gas of the filter. It is preferable to reach at least the end surface on the generation chamber side. In that case, the partition member extends continuously from the inner peripheral edge of the annular plate portion into the hollow communication portion of the filter by covering the end face of the filter with the annular plate portion. It is preferable that the cylindrical protrusion part which covers the inner peripheral surface near an end surface is included, and it is preferable that the said 2nd communicating hole is prescribed | regulated by the internal peripheral surface of the said cylindrical protrusion part. In that case, it is preferable that the cylindrical projecting portion is gradually reduced in diameter or increased so that the opening area of the second communication hole decreases or increases as the distance from the annular plate portion increases. .

  According to the present invention, a gas generator that facilitates a sealing process for preventing moisture absorption of a gas generating agent, dramatically improves workability during assembly, and as a result, can reduce manufacturing costs. can do.

It is the front view and right view of a cylinder type gas generator in one embodiment of the present invention. It is a schematic cross section of the cylinder type gas generator in one embodiment of the present invention. It is a schematic cross section which shows the state before the assembly | attachment to the housing of the 1st airtight container and the 2nd airtight container shown in FIG. It is a principal part expanded sectional view of the cylinder type gas generator in one embodiment of this invention.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In addition, one embodiment shown below illustrates the case where this invention is applied to what is called a cylinder type gas generator incorporated in a side airbag apparatus.

  FIG. 1 is a diagram showing an external structure of a cylinder type gas generator according to an embodiment of the present invention. FIG. 1 (A) is a front view and FIG. 1 (B) is a right side view. Moreover, FIG. 2 is a figure which shows the internal structure of the cylinder type gas generator in this Embodiment, and is a schematic cross section along the II-II line | wire shown to FIG. 1 (A) and FIG. 1 (B). . 3 is a schematic cross-sectional view showing a state before the first sealed container and the second sealed container shown in FIG. 2 are assembled to the housing, and FIG. 3 (A) shows the first sealed container. 3 (B) shows the second sealed container. Below, with reference to these FIG. 1 thru | or FIG. 3, the external appearance structure and internal structure of the cylinder type gas generator 1 in this Embodiment are demonstrated.

  As shown in FIG. 1 (A), FIG. 1 (B), and FIG. 2, the cylinder type gas generator 1 in the present embodiment has a long cylindrical outer shape, and both ends in the axial direction are closed. It has a housing as an outer shell member. A housing as an outer shell member extends along the same direction as the axial direction of the first housing member 10, and a bottomed cylindrical first housing member 10 having a peripheral wall portion 11 and a bottom wall portion 12 closed at one end. And a cylindrical second housing member 20 having a penetrating portion 23. The second housing member 20 has a later-described caulking fixing groove 21 at a predetermined position on its outer peripheral surface, and the groove 21 extends along the circumferential direction on the outer peripheral surface of the second housing member 20. It is formed in an annular shape.

  The second housing member 20 is fixed to the first housing member 10 so as to close the open end of the first housing member 10. Specifically, in a state in which a part of the second housing member 20 is inserted into the opening end of the first housing member 10, a portion corresponding to the groove 21 provided on the outer peripheral surface of the second housing member 20. The second housing member 20 is caulked and fixed to the first housing member 10 by reducing the diameter of the peripheral wall portion 11 of the first housing member 10 radially inward and engaging with the groove 21. As a result, one end of the housing in the axial direction is constituted by the second housing member 20, and the other end of the housing in the axial direction is constituted by the bottom wall portion 12 of the first housing member 10. become.

  The caulking fixing is caulking fixing called eight-side caulking, in which the peripheral wall portion 11 of the first housing member 10 is uniformly reduced in diameter in the radial direction. By performing the eight-side caulking, the caulking portion 14 is provided on the peripheral wall portion 11 of the first housing member 10. If the above-mentioned eight-side caulking is used, airtightness inside the housing can be ensured to a considerable extent without interposing a seal member between the first housing member 10 and the second housing member 20 to be caulked and fixed.

  The first housing member 10 may be composed of a metal member such as stainless steel, steel, aluminum alloy, stainless alloy, or a bottomed cylindrical shape by pressing a rolled steel plate represented by SPCE. It may be composed of a metal press-molded product formed into a metal. When the first housing member 10 is formed of a press-formed product of a rolled steel plate, the first housing member 10 is formed easily and inexpensively as compared with the case where a metal member such as stainless steel or steel is used. As well as significant weight savings. On the other hand, the 2nd housing member 20 is comprised with metal members, such as stainless steel, steel, an aluminum alloy, and a stainless alloy.

  A partition member 40 is disposed in a space inside the housing constituted by the first housing member 10 and the second housing member 20. The partition member 40 divides a space inside the housing into a working gas generation chamber and a filter chamber in the axial direction. The working gas generation chamber is located at a substantially central portion in the axial direction of the housing, and a first sealed container 80 described later is accommodated therein. The filter chamber is located on the other end side in the axial direction of the housing (that is, on the bottom wall 12 side of the first housing member 10), and a filter 70 described later is accommodated therein.

  As shown in FIG. 2, an igniter (squib) 30 and a transfer agent (enhancer) 61 as ignition means are arranged at one end of the housing in the axial direction (that is, a portion near the second housing member 20). Yes. The igniter 30 and the transfer charge 61 as ignition means are for generating a flame for burning a gas generating agent 62 described later, and the transfer charge 61 is housed in the second sealed container 90. ing. A space inside the housing in which the igniter 30 and the second sealed container 90 are accommodated corresponds to an ignition chamber. That is, the ignition chamber is located in a portion near one end portion in the axial direction of the housing, and is defined by the peripheral wall portion 11 of the first housing member 10, the second housing member 20, and a first sealed container 80 described later. Is done.

  The igniter 30 is inserted into the through portion 23 of the second housing member 20 and fixed by caulking. More specifically, the second housing member 20 has a caulking portion 24 at an end portion facing the space inside the housing, and the igniter 30 is inserted into the through portion 23 so that the second housing member 20 is inserted. By caulking the caulking portion 24 in a state where the igniter 30 is clamped to the second housing member 20, the igniter 30 is clamped by the second housing member 20 and the igniter 30 is fixed to the second housing member 20.

  The igniter 30 is an ignition device for generating a flame, and includes a base portion 31, an ignition portion 32, and a terminal pin 33. The base 31 is a part for inserting and holding the pair of terminal pins 33, and is provided adjacent to the ignition part 32. The ignition unit 32 includes an igniting agent that ignites during operation and a resistor for burning the igniting agent. The terminal pin 33 is connected to the ignition unit 32 in order to ignite the igniting agent. More specifically, in the igniter 30, a pair of terminal pins 33 held by the base portion 31 are inserted into the ignition portion 32, and a resistor (bridge wire) is attached so as to connect the tips thereof. The ignition part 32 is filled with an ignition agent so as to surround the body or to be in contact with the resistor. As a resistor, a resistance wire made of an alloy containing nichrome wire or platinum and tungsten is generally used, and as an igniter, ZPP (zirconium / potassium perchlorate), ZWPP (zirconium / tungsten / potassium perchlorate), Lead tricinate or the like is used. The squib cup that surrounds the ignition unit 32 is generally made of metal or plastic.

When a collision is detected, a predetermined amount of current flows through the resistor via the terminal pin 33. When a predetermined amount of current flows through the resistor, Joule heat is generated in the resistor, and the ignition powder starts to burn upon receiving this heat. The high temperature flame generated by the combustion ruptures the squib cup containing the igniting agent. The time from when the current flows through the resistor until the igniter 30 is activated is 3 milliseconds or less when a nichrome wire is used as the resistor.

  As described above, the transfer charge 61 is accommodated in the second sealed container 90. The second sealed container 90 includes a bottomed cylindrical cup portion 91 and a cap portion 92 that closes the opening of the cup portion 91. The second sealed container 90 is connected to the igniter 30 at a position near one end portion in the axial direction of the housing. Interpolated to connect. In the second sealed container 90, the cup portion 91 and the cap portion 92 are combined and joined, so that an accommodation space 93 formed inside the second sealed container 90 is formed outside the second sealed container 90. It is hermetically sealed. As the cup part 91 and the cap part 92, a metal member formed by pressing a metal thin plate (foil) such as copper, aluminum, a copper alloy, or an aluminum alloy, injection molding, sheet molding, etc. The formed resin member or the like is used. In addition, brazing, bonding, winding and the like are suitably used for joining the cup portion 91 and the cap portion 92.

The explosive charge 61 is ignited by a flame generated by the operation of the igniter 30 and burns to generate heat particles. It is necessary for the transfer agent 61 to be able to start combustion of a gas generating agent 62 to be described later with certainty. Generally, from a metal powder / oxidizer represented by B / KNO ₃ or the like. A composition having a high burning rate and a high exothermic property is used, such as a composition having a higher combustion rate than the gas generating agent 62 described later. As the explosive charge 61, a powdery one, a one molded into a predetermined shape by a binder, or the like is used. Examples of the shape of the transfer charge molded by the binder include various shapes such as a granular shape, a columnar shape, a sheet shape, a spherical shape, a single-hole cylindrical shape, a porous cylindrical shape, and a tablet shape.

  A first cushion member 63 is disposed in the ignition chamber between the second sealed container 90 and the second housing member 20 and in a portion surrounding the ignition unit 32 of the igniter 30. The first cushion material 63 is a member for fixing various internal components described later in the axial direction inside the housing, and at the same time, a member for absorbing the variation in the axial length of the internal components described above. But there is. Therefore, the first cushion material 63 is sandwiched and fixed in the axial direction of the housing by the second sealed container 90 and the second housing member 20 described above. As the first cushion material 63, for example, a ceramic fiber molded body, foamed silicon, or the like can be used.

  As shown in FIG. 2, the working gas generation chamber is defined by the peripheral wall portion 11 of the first housing member 10, the second sealed container 90, and the partition member 40, and the working gas generation chamber includes the first as described above. A sealed container 80 is arranged. The first sealed container 80 includes a bottomed cylindrical cup portion 81 and a cap portion 82 that closes the opening of the cup portion 81, and is inserted into a space inside the housing. In the first sealed container 80, the storage space 83 formed inside the first sealed container 80 is formed from the outside of the first sealed container 80 by joining the cup part 81 and the cap part 82 together. It is hermetically sealed. As the cup part 81 and the cap part 82, a metal member formed by pressing a metal thin plate (foil) such as copper, aluminum, a copper alloy, and an aluminum alloy, injection molding, sheet molding, etc. The formed resin member or the like is used. In addition, brazing, bonding, winding and the like are preferably used for joining the cup portion 81 and the cap portion 82.

  The gas generating agent 62, the partition member 50, and the second cushion material 64 are accommodated in the accommodation space 83 of the first sealed container 80. More specifically, the second cushion material 64 is disposed at the end portion of the first sealed container 80 on the side where the second sealed container 90 is located, and the portion where the second cushion material 64 is disposed is arranged. The gas generating agent 62 and the partition member 50 are disposed in the portion other than the portion.

  The partition member 50 is configured by a bottomed cylindrical member having a hollow portion 55 inside and closed at one end, and includes a flange portion 51, a cylindrical portion 52, and a bottom portion 53. The flange portion 51 is disposed at the end portion of the first sealed container 80 on the partition member 40 side (that is, the end portion on the side where the second cushion material 64 is not disposed). The cylindrical portion 52 extends continuously from the inner peripheral edge of the flange portion 51 and is located so as to protrude from the end of the first sealed container 80 on the partition member 40 side toward the inside of the working gas generation chamber. The bottom 53 extends continuously from the cylindrical portion 52 and closes the end of the cylindrical portion 52 on the second sealed container 90 side. In addition, the bottom part 53 is spaced apart from the second cushion material 64 described above by a predetermined distance.

  Here, the gas generating agent 62 described above is accommodated in a portion of the working gas generation chamber excluding the hollow portion 55 of the partition member 50. That is, the gas generating agent 62 is accommodated in the space surrounding the cylindrical portion 52 of the partition member 50 and the space located between the partition member 50 and the second cushion material 64 in the working gas generation chamber. .

  The gas generating agent 62 is ignited by the hot particles generated by the combustion of the charge transfer agent 61 ignited by the igniter 30, and generates gas by burning. The gas generating agent 62 is generally formed as a molded body containing a fuel, an oxidant, and an additive. As the fuel, for example, a triazole derivative, a tetrazole derivative, a guanidine derivative, an azodicarbonamide derivative, a hydrazine derivative, or a combination thereof is used. Specifically, for example, nitroguanidine, guanidine nitrate, cyanoguanidine, 5-aminotetrazole and the like are preferably used. The oxidizing agent is selected from basic nitrates such as basic copper nitrate, perchlorates such as ammonium perchlorate and potassium perchlorate, alkali metals, alkaline earth metals, transition metals, and ammonia. Nitrate containing cation is used. As the nitrate, for example, sodium nitrate, potassium nitrate and the like are preferably used. In addition, examples of the additive include a binder, a slag forming agent, and a combustion adjusting agent. As the binder, for example, cellulose derivatives such as hydroxypropylene methylcellulose, organic binders such as metal salts and stearates of carboxymethylcellulose, and inorganic binders such as synthetic hydroxytalcite and acidic clay can be suitably used. As the slag forming agent, silicon nitride, silica, acid clay, etc. can be suitably used. Moreover, as a combustion regulator, a metal oxide, ferrosilicon, activated carbon, graphite, etc. can be used suitably.

  The shape of the molded body of the gas generating agent 62 includes various shapes such as granules, pellets, columns, and disks. In addition, a porous (for example, a single-hole cylindrical shape or a porous cylindrical shape) having a hole inside the molded body is also used. These shapes are preferably selected as appropriate in accordance with the specifications of the airbag apparatus in which the cylinder type gas generator 1 is incorporated. For example, the working gas generation rate changes with time during combustion of the gas generating agent 62. It is preferable to select an optimum shape according to the specification, such as selecting a shape. In addition to the shape of the gas generating agent 62, it is preferable to appropriately select the size and filling amount of the molded body in consideration of the linear combustion rate, the pressure index, etc. of the gas generating agent 62.

  A plurality of first communication holes 54 are provided in the cylindrical portion 52 of the partition member 50 along the circumferential direction and the axial direction. The first communication hole 54 is a hole for communicating the space in which the gas generating agent 62 is accommodated with the hollow portion 55 of the partition member 50, and is not provided in the bottom 53 of the partition member 50.

  The partition member 50 functions as a pressure partition for generating a pressure difference between the hollow portion 55 and the space in which the gas generating agent 62 is accommodated during operation, and has a predetermined strength. It is composed of. Specifically, the partition member 50 is made of a metal member such as stainless steel, steel, an aluminum alloy, or a stainless alloy.

  The second cushion material 64 corresponds to a crushing prevention member for preventing the gas generating agent 62 made of a molded body from being crushed by vibration or the like, and preferably a ceramic fiber molded body or foamed silicon is used. The The second cushion material 64 is opened or divided by the combustion of the charge transfer 61 at the time of operation, and may be burned out in some cases.

  As shown in FIG. 2, the partition member 40 divides the space inside the housing into a working gas generation chamber and a filter chamber in the axial direction. The partition member 40 is disposed so as to be in contact with the first sealed container 80 described above in the space inside the housing, and has an annular plate portion 41, a cylindrical projecting portion 42, and a second communication hole 43. Yes. The annular plate portion 41 is disposed in contact with the first sealed container 80 so as to be orthogonal to the axis of the housing. The cylindrical projecting portion 42 extends continuously from the inner peripheral edge of the annular plate portion 41 and is located so as to project in a direction away from the first sealed container 80 described above. The second communication hole 43 is defined by the cylindrical protrusion 42 and is a hole for communicating the hollow portion 55 of the partition member 50 and the filter chamber.

  The partition member 40 is fitted or loosely fitted to the housing, and the housing is not subjected to caulking processing for fixing the partition member 40. Here, the fitting includes so-called press-fitting and refers to a state in which the outer peripheral end of the annular plate portion 41 of the partition member 40 is attached in a state of being in contact with the inner peripheral surface of the housing. In addition, loose fitting refers to a state in which the outer peripheral end of the annular plate portion 41 of the partition member 40 and the inner peripheral surface of the housing are not necessarily in contact with each other over the entire circumference, and are inserted with a slight gap (play). .

  The partition member 40 is attached to an end portion of the filter 70 to be described later on the working gas generation chamber side, and is sandwiched between the filter 70 and the first hermetic container 80 that houses the gas generating agent 62 described above. Is supported by The partition member 40 is formed by, for example, pressing a metal plate-like member such as stainless steel, steel, an aluminum alloy, or a stainless alloy.

  As shown in FIG. 2, the filter chamber is defined by the peripheral wall portion 11 and the bottom wall portion 12 of the first housing member 10 and the partition member 40, and the filter 70 is disposed in the filter chamber. The filter chamber is provided adjacent to the working gas generation chamber via the partition member 40, and is located closer to the other end side of the housing than the working gas generation chamber (that is, the bottom wall portion 12 side of the first housing member 10). doing.

  The filter 70 is a cylindrical member that extends in the same direction as the axial direction of the housing and has a hollow communication portion 71 that reaches the axial end surface thereof. The end surface on the side of the working gas generation chamber in the axial direction contacts the partition member 40. The other end face is in contact with the bottom wall portion 12 of the first housing member 10. The outer peripheral surface of the filter 70 is in contact with the inner peripheral surface of the peripheral wall portion 11 of the first housing member 10. By using such a filter 70 made of a cylindrical member, the flow resistance of the working gas flowing through the filter chamber during operation can be kept low, and an efficient working gas flow can be realized.

  As the filter 70, for example, a metal wire material such as stainless steel or steel or a mesh material in which a metal wire material is knitted is wound or pressed by pressing. Specifically, a knitted wire mesh, a plain weave wire mesh, an assembly of crimped metal wires or the like is used as the mesh material. Thus, the filter 70 formed by winding or compacting a metal wire in a cylindrical shape includes a gap in the inside thereof, and enables the above-described working gas to flow. When the working gas generated in the working gas generation chamber passes through the filter 70, the filter 70 functions as a cooling means that cools the working gas by taking away the high-temperature heat of the working gas. It also functions as a removing means for removing residues (slag) and the like contained in the gas.

  As shown in FIG. 2, a gas outlet 13 is provided in the peripheral wall portion 11 of the first housing member 10 that defines the filter chamber. The gas outlet 13 is a hole for discharging the working gas generated inside the cylinder type gas generator 1 to the outside, and extends along the circumferential direction and the axial direction of the peripheral wall portion 11 of the first housing member 10. A plurality are provided.

  A female connector (not shown) is attached to the end of the cylinder type gas generator 1 on the side where the second housing member 20 is disposed. More specifically, there is a female connector in which a male connector of a harness for transmitting a signal from a collision detection sensor provided separately from the cylinder type gas generator 1 is connected to a recess 22 provided in the second housing member 20. Mounted. A shorting clip (not shown) is attached to the female connector as necessary. This shorting clip is attached in order to prevent the cylinder type gas generator 1 from malfunctioning due to electrostatic discharge or the like when the cylinder type gas generator 1 is transported. In the stage, when the male connector of the harness is inserted into the female connector, the contact with the terminal pin 33 is released.

  Next, the operation | movement at the time of the action | operation of the cylinder type gas generator 1 demonstrated above is demonstrated with reference to FIG. When a vehicle equipped with an airbag device incorporating the cylinder type gas generator 1 according to the present embodiment collides, the collision is detected by a collision detection unit provided separately in the vehicle, and ignition is performed based on this. The device 30 is activated. When the igniter 30 is activated, the pressure in the igniter 32 is increased due to combustion of the igniting agent, whereby the igniter 32 is ruptured and the flame flows out of the igniter 32.

  After the igniter 32 is ruptured, the temperature and pressure of the space surrounding the igniter 32 are increased, and the second sealed container 90 is melted or ruptured. Thereby, the transfer charge 61 accommodated in the 2nd airtight container 90 is ignited and burned by the flame produced when the igniter 30 act | operates, and generates a lot of thermal particles. The large amount of generated heat particles melts or ruptures the cap portion 82 of the first sealed container 80, opens or divides the second cushion material 64, and reaches the gas generating agent 62.

  The hot particles that have reached the gas generating agent 62 sequentially ignite and burn the gas generating agent 62 from the side where the igniter 30 is located, thereby generating a large amount of working gas. The working gas generated in this manner passes through the first communication hole 54 provided in the partition member 50 and flows into the hollow portion 55 of the partition member 50, and the cup of the first sealed container 80 positioned at the end thereof. The portion 81 is ruptured and flows into the filter chamber via the second communication hole 43 provided in the partition member 40.

  The working gas that has flowed into the filter chamber enters the filter 70 via the hollow communication portion 71 of the filter 70, passes through the filter 70, is cooled to a predetermined temperature, and is discharged from the gas outlet 13. It is ejected to the outside of the cylinder type gas generator 1. The working gas ejected from the gas ejection port 13 is guided into the airbag to inflate and deploy the airbag.

  Here, in the cylinder type gas generator 1 according to the present embodiment, the portion located between the bottom 53 of the partition member 50 and the second cushion material 64 in the initial stage of combustion of the gas generating agent 62. The gas generating agent 62 sequentially burns from the side where the second sealed container 90 is located, and the internal pressure of the portion excluding the hollow portion 55 of the working gas generating chamber rapidly rises, and the combustion of the gas generating agent 62 is promoted. The working gas flows into the hollow portion 55 via the first communication hole 54 provided in the cylindrical portion 52 of the partition member 50 without hindering the flow of the working gas by the combustion gas generating agent 62. After the initial stage of combustion of the gas generating agent 62 is completed, the portion of the gas generating agent 62 located in the space surrounding the cylindrical portion 52 of the partition member 50 is sequentially burned from the side where the second sealed container 90 is located. Then, the working gas is stably generated while maintaining the internal pressure of the working gas generating chamber except for the hollow portion 55, and the working gas generated by the unburned gas generating agent 62 is operated without being hindered. The gas flows into the hollow portion 55 via the first communication hole 54 provided in the cylindrical portion 52 of the partition member 50. Therefore, by adopting a configuration like the cylinder type gas generator 1 in the present embodiment, the function of the partition member 50 prevents the unburned gas generating agent from becoming the flow resistance of the working gas. As a result, a cylinder type gas generator having excellent output characteristics can be obtained.

  Next, the assembly procedure of the cylinder type gas generator 1 in this Embodiment is demonstrated. First, as shown in FIG. 3A, a first sealed container 80 including a cup part 81 and a cap part 82 is prepared, and a partition member 50 and a gas generating agent 62 are provided in the cup part 81 of the first sealed container 80. These are accommodated in the order of the second cushion material 64. Then, the opening of the cup part 81 is closed by the cap part 82, and the cap part 82 is joined to the cup part 81. Next, as shown in FIG. 3 (B), a second sealed container 90 composed of a cup part 91 and a cap part 92 is prepared, and the transfer charge 61 is accommodated in the cup part 91 of the second sealed container 90. . Then, the opening of the cup portion 91 is closed by the cap portion 92 and the cap portion 92 is joined to the cup portion 91.

  Next, referring to FIG. 2, the filter 70 in which the partition member 50 is assembled to the first housing member 10 is inserted and fixed. Subsequently, the first sealed container 80 containing the gas generating agent 62 and the like described above is inserted and fixed to the first housing member 10 to which the filter 70 and the partition member 50 are assembled. At this time, the first sealed container 80 is press-fitted and fixed to the peripheral wall portion 11 of the first housing member 10. Further, the end surface of the first sealed container 80 is abutted against the partition member 50.

  Subsequently, the second sealed container 90 in which the above-described transfer charge 61 is accommodated is inserted and fixed to the first housing member 10. At this time, the second sealed container 90 is press-fitted and fixed to the peripheral wall portion 11 of the first housing member 10. Subsequently, the second housing member 20 in which the igniter 30 and the first cushion material 63 are assembled is inserted into the first housing member 10. Then, the first housing member 10 and the second housing member 20 are caulked and fixed. Thus, the assembly of the cylinder type gas generator 1 configured as shown in FIGS. 1 and 2 is completed.

  In the cylinder type gas generator 1 in the present embodiment described above, the gas generating agent 62 is disposed in the working gas generating chamber in a state of being sealed and accommodated by the first sealed container 80, and the transfer charge 61 is the first. Two sealed containers 90 are arranged in the ignition chamber in a state of being sealed and accommodated. For this reason, it is not necessary to perform a sealing process for hermetically sealing the gas generating agent 62 and the transfer agent 61 to the housing, and as a result, each part of the housing is made using a fragile member such as an O-ring or a sealing tape. It becomes unnecessary to perform the sealing process, and the sealing process for preventing the gas generating agent 62 and the transfer agent 61 from absorbing moisture is greatly facilitated. Therefore, by adopting the above-described configuration, it is possible to dramatically improve the workability at the time of assembly, and it is possible to provide a cylinder type gas generator that can suppress the manufacturing cost.

  Further, in the cylinder type gas generator 1 according to the present embodiment, when the gas generating agent 62 is accommodated in the first sealed container 80, the partition member 50 and the second cushion material that are disposed in the working gas generation chamber. Since 64 is accommodated in the first sealed container 80 together with the gas generating agent 62, these members can be assembled to the housing at a time in a sub-assembled state. Therefore, by adopting the above configuration, the assembly work can be further facilitated, and a cylinder-type gas generator that can further suppress the manufacturing cost can be obtained.

  In addition, by using the cylinder type gas generator 1 in the present embodiment, it is not necessary to apply a sealing process to the housing for hermetically sealing the gas generating agent 62 and the transfer agent 61 as described above. As a result, the outer shape of the housing can be reduced (that is, the diameter can be reduced or shortened), or the pressure resistance can be increased by increasing the wall thickness of the housing. In addition, a cylinder type gas generator having a structure advantageous for high pressure resistance can be obtained. In addition, the structure of the cylinder type gas generator 1 in this Embodiment becomes suitable especially when the outer diameter of a housing shall be 15 mm or more and 20 mm or less.

  Also, in the cylinder type gas generator, from the viewpoint of safety, when heat is applied to the cylinder type gas generator from the outside, the transfer charge may be ignited before the gas generating agent. Desired. For this reason, normally, the charge is prepared so that the spontaneous ignition point of the propellant is lower than the spontaneous ignition point of the gas generant or the autoignition agent is mixed with the charge. It is configured to ignite. Here, in the cylinder type gas generator 1 in the present embodiment, the second sealed container 90 is fixed by being press-fitted into the first housing member 10, and the outer periphery of the second sealed container 90 after assembly. The surface and the inner peripheral surface of the first housing member 10 are in direct contact with each other. Therefore, heat from the outside is efficiently transmitted to the explosive 61 through the housing, and it can be said that the configuration is more preferable from the viewpoint of safety described above.

  By the way, in the cylinder type gas generator 1 in this Embodiment, as the cylindrical protrusion part 42 of the partition member 40 which divides a working gas production | generation chamber and a filter chamber moves away from the annular plate part 41 (from a working gas production | generation chamber). It is configured in a conical plate shape gradually reduced in diameter so that the opening area of the second communication hole 43 defined by the cylindrical projecting portion 42 decreases as it moves away and toward the tip of the cylindrical projecting portion 42. And is fitted or loosely fitted to the housing. Therefore, the first housing member 10 is not subjected to caulking for fixing the partition member 40. Therefore, in the cylinder type gas generator 1 in the present embodiment, the assembly can be easily performed as compared with the conventional case. Hereinafter, the reason why the partition member 40 sufficiently functions as a pressure partition even when such an assembly structure is adopted will be described.

  FIG. 4 is an enlarged cross-sectional view of a main part in which the vicinity of the position where the partition member of the cylinder type gas generator in the present embodiment is provided, and FIG. 4 (A) shows the start of operation of the cylinder type gas generator. FIG. 4B is a diagram showing a state immediately after, and FIG. 4B is a diagram showing a state after a predetermined time has elapsed from the start of operation. In FIGS. 4A and 4B, the flow direction of the working gas is indicated by an arrow G, and the specific illustration of the working gas generation chamber is omitted.

  As shown in FIG. 4A, immediately after the start of the operation of the cylinder type gas generator 1, the thrust of the high-temperature and high-pressure working gas generated in the working gas generation chamber (that is, the internal pressure of the working gas generation chamber) ), And the annular plate portion 41 of the partition member 40 receives a force (a force indicated by an arrow A in the drawing) toward the filter 70 along the axial direction of the housing. As a result, the annular plate portion 41 of the partition member 40 starts moving toward the filter 70 side, and the portion of the filter 70 surrounded by the partition member 40 and the housing (that is, the working gas generation chamber side of the filter 70). The portion in the vicinity of the end portion, the portion included in the region B1 shown in the drawing) is compressed along the axial direction of the housing as the annular plate portion 41 moves.

  Here, inside the filter 70, there is a void formed as a result of the filter 70 being formed by winding or pressing a metal wire or a net material knitted with a metal wire, or by pressing and compacting. As shown in FIG. 4B, the volume of the gap decreases with the movement of the annular plate portion 41, and the metal wire is more densely filled in the region B1, and the radial direction of the housing A force is generated to push the cylindrical protrusion 42 of the partition member 40 inward along the radial direction of the housing. However, a force (a force indicated by an arrow C in the drawing) toward the outside along the generally radial direction of the housing is applied to the cylindrical projecting portion 42 of the partition member 40 as the internal pressure increases. Therefore, the force to push the cylindrical projecting portion 42 of the partition member 40 inward along the radial direction of the housing is defeated by the force, and the reaction force (the force indicated by the arrow D in the figure) is the housing. And a contact portion (region E shown in the drawing) between the filter 70 and the filter 70. Thereby, a frictional force is generated at a contact portion between the housing and the filter 70, and the frictional force becomes a braking force that suppresses the partition member 40 from further moving toward the filter 70 side.

  Here, the reaction force (the force indicated by the arrow D in the figure) acts as a force acting in a direction intersecting the radial direction and the axial direction of the housing, and thus prevents the partition member 40 from moving over a wide range of the housing. Therefore, the amount of movement of the partition member 40 remains small based on the braking force. Therefore, the function as a pressure partition is substantially ensured by the partition member 40 after the movement and the filter 70 which is pressed and compressed along with this, and the internal pressure of the working gas generation chamber is maintained high. At the same time, breakage of the filter 70 is prevented. Therefore, the partition member 40 functions sufficiently as a pressure partition wall even if the partition member 40 is not fixed by caulking the housing.

  Further, in the cylinder type gas generator 1 according to the present embodiment, the cylindrical protrusion 42 of the partition member 40 is configured to cover only the vicinity of the end of the filter 70 on the working gas generation chamber side. Therefore, a state where a sufficient gap is formed is maintained inside the filter 70 in the portion located in the region B2 shown in FIG. 4B, and the movement and deformation of the partition member 40 described above are maintained. The working gas can flow smoothly in the portion without being affected. Therefore, the cooling function of the working gas and the slag collecting function of the filter 70 are not impaired.

  Furthermore, in the cylinder type gas generator 1 according to the present embodiment, when the partition member 40 and the filter 70 are projected on a plane orthogonal to the axis along the axial direction of the housing, the inner edge of the projection region of the filter 70 is obtained. Is configured so as not to be located inside the inner edge of the projection area of the partition member 40. That is, when the partition member 40 and the filter 70 are viewed in plan from the working gas generation chamber side, the relative positional relationship between the partition member 40 and the filter 70 is adjusted so that the filter 70 is completely covered by the partition member 40. ing. With this configuration, the high-temperature and high-pressure working gas that has passed through the second communication hole 43 of the partition member 40 flows along the inner peripheral surface of the filter 70, so that the working gas directly enters the filter 70. The ratio of spraying can be greatly reduced.

  In the cylinder type gas generator 1 in the present embodiment, since the partition member 40 is held by the portion of the filter 70 located in the region B1 described above during operation, the cylinder type gas generator 1 is operated only by the partition member 40. It is not necessary to design the partition member 40 so that it can withstand the thrust force of the gas, and the thickness can be reduced as compared with the conventional case. Specifically, in consideration of the specifications of a general cylinder type gas generator, when a steel material is used as the partition member 40, it is sufficient that the thickness is approximately 0.7 mm or more.

  As described above, by adopting a configuration like the cylinder type gas generator 1 in the present embodiment, it is not necessary to carry out caulking on the housing for mounting the partition member 40. The effect that the partition member 40 can be thinned is obtained. Therefore, when it sees as the cylinder type gas generator 1 whole, it becomes possible to reduce in size and weight, without reducing a performance. In addition, by adopting the above configuration, the work of caulking the partition member 40 to the housing is not necessary, and the manufacturing cost can be reduced. Therefore, a cylinder type gas generator that can be reduced in size and weight without degrading performance and can be easily manufactured can be provided.

  In the present embodiment described above, the first sealed container 80 in which the gas generating agent 62 and the like are accommodated and the second sealed container 90 in which the transfer charge 61 is accommodated are press-fitted and fixed to the housing. Although the mold gas generator 1 has been described as an example, it is not always necessary to be configured as such, and the first sealed container 80 and the second sealed container 90 may be loosely fitted in the housing, respectively. . However, in this case, it is necessary that the first sealed container 80 and the second sealed container 90 are fixed in the axial direction of the housing using the first cushion material 63 and the like described above.

  Moreover, in this Embodiment demonstrated above, although the case where it comprised by the press-molded article formed by press-molding a rolled steel plate as the 1st housing member 10 was demonstrated, it replaced with this, The first housing member 10 may be formed by drawing and forming a seamless tube or a molded product obtained by closing one of the end portions in the axial direction of the ERW tube.

  Further, in the present embodiment described above, the cylinder type gas generator 1 formed by connecting the first housing member 10 and the second housing member 20 by caulking and fixing is described as an example. Of course, welding may be used to fix the first housing member 10 and the second housing member 20 together.

  Further, in the present embodiment described above, the igniter 30 has been described by exemplifying one using a nichrome wire as a resistor as a heat source. However, a so-called semiconductor bridge is used as the heat source. It is also possible to use an igniter utilized as

  Moreover, in this Embodiment demonstrated above, although the case where it was set as the shape which diameter-reduced as the shape of the cylindrical protrusion part 42 of the partition member 40 goes to a front-end | tip demonstrated was demonstrated, the said cylindrical protrusion It is also possible to make the shape of the portion 42 larger in diameter as it goes to the tip. In such a configuration, the opening area of the second communication hole 43 gradually increases as the distance from the annular plate portion 41 increases. In this case as well, when the cylinder-type gas generator 1 is activated, A frictional force is generated at the contact portion between the housing and the filter 70, and the frictional force becomes a braking force that suppresses the partition member 40 from moving further toward the filter 70, and the above-described effects are obtained.

  Moreover, in this Embodiment demonstrated above, although the case where the shape of the cylindrical protrusion part 42 of the partition member 40 was made into the shape of a conical plate was demonstrated, the shape of the said cylindrical protrusion part 42 is shown. For example, the cross-sectional shape may be curved. In any case, the shape of the cylindrical projecting portion 42 is such that the force applied to the cylindrical projecting portion 42 as the internal pressure increases acts in a direction intersecting both the radial direction and the axial direction of the housing. It suffices if the inner peripheral surface of the cylindrical protrusion 42 is not arranged in parallel with the axial direction of the housing.

  In addition, in the present embodiment described above, the case where the present invention is applied to a cylinder type gas generator incorporated in a side airbag device is described as an example. It is not limited to a cylinder type gas generator incorporated in a passenger seat airbag device, curtain airbag device, knee airbag device, or the like, and a long gas output section similar to a cylinder type gas generator. The present invention can also be applied to a so-called T-shaped gas generator.

  Thus, the one embodiment disclosed this time is illustrative in all respects and is not restrictive. The technical scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  DESCRIPTION OF SYMBOLS 1 Cylinder-type gas generator, 10 1st housing member, 11 Perimeter wall part, 12 Bottom wall part, 13 Gas outlet, 14 Caulking part, 20 2nd housing member, 21 Groove, 22 Recessed part, 23 Through part, 24 Caulking part , 30 igniter, 31 base part, 32 ignition part, 33 terminal pin, 40 partition member, 41 annular plate part, 42 cylindrical projection part, 43 second communication hole, 50 partition member, 51 flange part, 52 cylindrical part, 53 bottom part, 54 first communication hole, 55 hollow part, 61 explosive agent, 62 gas generating agent, 63 first cushion material, 64 second cushion material, 70 filter, 71 hollow communication part, 80 first sealed container, 81 cup Part, 82 cap part, 83 accommodation space, 90 2nd airtight container, 91 cup part, 92 cap part, 93 accommodation space.

Claims (6)

A working gas generation chamber in which a working gas is generated by combustion of the gas generating agent, and a filter chamber in which a filter through which the working gas generated in the working gas generation chamber passes are accommodated in the axial direction. A long cylindrical housing with both ends closed;
An ignition means disposed at one end of the housing in the axial direction and generating a flame for burning the gas generating agent;
A partition member located inside the housing and partitioning the space inside the housing into the working gas generation chamber and the filter chamber in the axial direction;
A partition member that partitions the working gas generation chamber;
A crush prevention member for preventing crushing of the gas generating agent by vibration,
The filter chamber is located on the other end side of the housing from the working gas generation chamber,
A portion defining the filter chamber of the housing is provided with a plurality of gas jets for ejecting the working gas that has passed through the filter to the outside.
The housing further includes an ignition chamber in which the ignition means is disposed,
The ignition means includes an igniter including an igniter that generates a flame by burning, and a transfer agent for transmitting the flame generated in the igniter to the gas generating agent,
In the working gas generation chamber, a first sealed container having a sealed storage space is disposed,
In the accommodation space of the first sealed container, the gas generating agent, the partition member, and the crush prevention member are arranged,
The partition member is configured by a bottomed cylindrical member having a hollow portion arranged coaxially with the housing, and from the end of the first sealed container on the partition member side in the axial direction of the housing A cylindrical portion extending along the bottom, and a bottom portion that closes an end of the cylindrical portion on the ignition means side,
The bottom portion is located closer to the partition member than the end on the ignition means side of the first sealed container,
The gas generating agent is accommodated in the accommodating space of the first sealed container in a portion excluding the hollow portion of the partition member,
Wherein the cylindrical portion, a plurality of first communicating holes communicating are provided before and Symbol space gas generating agent is accommodated and said hollow portion,
A second communication hole for communicating the hollow portion and the filter chamber is provided in the central portion of the partition member ,
In the ignition chamber, a second sealed container having a sealed storage space is disposed,
In the housing space of the second sealed container, the transfer charge is disposed,
The second sealed container is composed of a member that is melted or ruptured by a flame generated by burning the ignition powder,
The first airtight container is composed of a member that melts or bursts by heat particles generated by burning the transfer charge,
The gas generator, wherein the first sealed container and the second sealed container are opposed to each other in the axial direction over the entire area in the radial direction of the space inside the housing . The gas generator according to claim 1, wherein the first sealed container and the second sealed container are in contact with each other. The gas generator according to claim 1 or 2 , wherein the first sealed container is disposed in the working gas generation chamber by being press-fitted and fixed inside the housing. The gas generator according to any one of claims 1 to 3 , wherein the crushing prevention member is disposed at an end portion on the ignition means side in the housing space of the first sealed container. The gas generator according to any one of claims 1 to 4 , wherein the second sealed container is disposed in the ignition chamber by being press-fitted and fixed inside the housing. The filter has a hollow communication portion extending along the axial direction of the housing,
The hollow communication part reaches at least the end surface of the filter on the working gas generation chamber side,
The partition member includes an annular plate portion that covers the end surface of the filter, and an inner periphery near the end surface of the filter by continuously extending from an inner peripheral edge of the annular plate portion toward the hollow communication portion of the filter. A cylindrical protrusion covering the surface,
The second communication hole is defined by an inner peripheral surface of the cylindrical protrusion,
The said cylindrical protrusion part is diameter-reduced or expanded gradually so that the opening area of a said 2nd communicating hole may reduce or increase as it distances from the said annular board part. Gas generator.

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