JP5247125B2 - 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 so-called cylinder type gas generator suitably incorporated in a side airbag device or the like.

  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. The 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 the vehicle or the like, and the airbag is deployed by instantly inflating and deploying the airbag at the time of the vehicle or the like collision. It is a safety device that catches the occupant'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.

  There are various types of gas generators based on specifications such as installation position and output with respect to a vehicle or 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 or the like. In a cylinder type gas generator, an igniter and a transfer charge are disposed at one end in the axial direction, a gas generating agent is disposed at a substantially central portion in the axial direction, and a filter and a gas outlet are disposed at the other end in the axial direction. Be placed.

  In this cylinder type gas generator, the flame generated by the operation of the igniter is transmitted to the gas generating agent through the combustion of the explosive charge, whereby the gas generating agent burns to generate high-temperature and high-pressure gas. . The generated high-temperature and high-pressure gas is ejected from the gas ejection port to the outside of the housing via the filter, and is used for inflation and deployment of the airbag.

  In the cylinder type gas generator, as described above, it is common to use a transfer charge to promote combustion of the gas generating agent. This transfer charge is usually disposed between the combustion chamber containing the gas generating agent and the igniter. In order to realize such a configuration, a bottomed cylindrical cup-shaped member filled with a transfer charge is prepared, and the ignition part of the igniter is covered with the cup-shaped member filled with the transfer charge. Generally, the cup-shaped member is arranged in the combustion chamber so that Documents disclosing a cylinder type gas generator having such a configuration include, for example, Japanese Patent Application Laid-Open No. 11-91494 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2000-203372 (Patent Document 2).

By the way, the combustion chamber containing the gas generating agent needs to be hermetically sealed. This is because when the outside air enters the combustion chamber from the outside space, the gas generating agent may absorb moisture due to moisture contained in the outside air that has entered, and the gas generating agent has absorbed moisture. This is because a desired gas output cannot be obtained. Therefore, in a conventional cylinder type gas generator, a seal portion is usually formed by interposing an O-ring between a holder for fixing an igniter and a housing fixed to the holder, and the seal portion Thus, the airtightness of the combustion chamber has been ensured. References disclosing such a cylinder-type gas generator using an O-ring include, for example, Japanese Patent Application Laid-Open No. 11-78766 (Patent Document 3) and Japanese Patent Application Laid-Open No. 2005-313812 (Patent Document). Reference 4).
JP-A-11-91494 JP 2000-203372 A Japanese Patent Laid-Open No. 11-78766 JP 2005-313812 A

  However, when the configurations as disclosed in the above-mentioned Patent Documents 3 and 4 are adopted, an O-ring for sealing processing is separately required, which complicates the assembly work and increases the cost due to an increase in the number of parts. Will occur. In order to prevent an increase in the number of parts, it is conceivable to join the holder and the housing by welding, but in this case as well, the work becomes complicated, resulting in an increase in manufacturing cost. As another method, it is conceivable to maintain the pressure contact state between the housing and the holder by press-fitting the holder into the housing or by crimping the housing toward the holder. It is difficult to ensure the required airtightness only by a simple sealing process.

  Therefore, the present invention has been made to solve the above-mentioned problems, and can be manufactured at low cost without increasing the number of parts, and airtightness between the housing and the holder can be easily secured. It is an object of the present invention to provide a gas generator that can be used.

The gas generator based on this invention is provided with the housing, the holder, the igniter, and the cup-shaped member. The housing is formed of a long cylindrical metal member including a combustion chamber in which a gas generating agent is accommodated. The holder is attached to the housing in a state in which at least a part thereof is inserted into an axially open end of the housing so as to face the combustion chamber, and toward a direction parallel to the axial direction of the housing. It consists of a metal member including a hollow opening that extends. The igniter includes an igniter in which an igniting agent is accommodated, and the igniter is disposed in the hollow opening with the igniter positioned on the combustion chamber side and fixed to the holder. The cup-shaped member defines a transfer charge storage chamber and is disposed in the combustion chamber so that the transfer charge stored in the transfer charge storage chamber faces the ignition unit. The cup-shaped member includes a seal portion that extends from a portion that defines the transfer charge storage chamber and that is interposed between the housing and the holder and seals a gap therebetween. The holder is fixed to the housing by caulking the peripheral wall of the housing at a portion corresponding to at least a part of the portion in which the holder is inserted, radially inward, and the seal portion is The housing is interposed between the housing and the holder at a portion corresponding to the portion caulked. A part of the portion where the holder is inserted into the housing is provided with a pressure contact portion where the inner peripheral surface of the housing and the outer peripheral surface of the holder are in direct contact.

By configuring in this way, the gap between the housing and the holder is filled by a part of the cup-shaped member in which the charge transfer material is accommodated, so that the sealing process in the part is realized. It is possible to easily and hermetically seal the combustion chamber without increasing it. Therefore, it is possible to provide a gas generator that can be manufactured at low cost and that can easily ensure airtightness between the housing and the holder. Also, with this configuration, the seal portion formed by extending a part of the cup-shaped member is interposed between the housing and the holder at the portion where the housing is caulked toward the holder. And since it is maintained in the compressed state or the distorted state in which the surface pressure is appropriately applied, a seal structure that exhibits good sealing characteristics can be realized by the portion. Therefore, the combustion chamber can be surely hermetically sealed, and a highly reliable gas generator can be obtained. In addition, by configuring in this way, high pressure resistance is maintained at the portion where the housing and the holder are in direct contact with each other, so that high reliability is ensured that no gas leakage occurs even when the gas generator is operating. Gas generators.
In the gas generator according to the present invention, it is preferable that the holder has an annular groove portion extending in a circumferential direction on an outer peripheral surface of a portion corresponding to a portion where the housing is caulked. It is desirable that the caulked portion of the housing is engaged with the annular groove.
By configuring in this way, the seal part is securely sandwiched between the housing and the holder and compressed or distorted when the housing is caulked, thereby realizing high airtightness. Is possible.

In the gas generator based on the present invention, the interpolated portion to the housing of the holder, to contain the open end indented portion against the of the housing preferably when the the seal portion, it is preferable that interposed between the housing and the holder in a portion corresponding to the portion where the holder is press-fitted.

  With this configuration, the seal portion formed by extending a part of the cup-shaped member is interposed between the housing and the holder at the portion where the holder is press-fitted into the housing, and has an appropriate surface. Since the compressed state or the strained state in which pressure is applied is maintained, a seal structure that exhibits good sealing characteristics can be realized by the portion. Therefore, the combustion chamber can be surely hermetically sealed, and a highly reliable gas generator can be obtained.

In the gas generator based on the present invention, the contact portion is preferably formed by caulked toward the peripheral wall of the upper Symbol housing radially inward.

  By comprising in this way, it can be set as the gas generator from which a high pressure | voltage resistant characteristic is acquired reliably.

  In the gas generator according to the present invention, it is preferable that the cup-shaped member includes a bottomed cylindrical cup portion that defines the explosive charge storage chamber. It is desirable to extend continuously from the open end of the cup portion.

  By comprising in this way, the simple structure of assembling | attaching to a housing in the state which covered the cup-shaped member on the outer peripheral surface of the end surface of a holder and the part continuous to the said end surface is realizable. Therefore, the gas generator can be easily assembled.

  In the gas generator according to the present invention, the cup-shaped member includes a bottomed cylindrical cup portion that defines the transfer charge-accommodating chamber and a lid portion that closes the open end of the cup portion. In this case, it is desirable that the transfer charge storage chamber is sealed by the cup portion and the lid portion.

  By comprising in this way, since it becomes possible to seal a gunpowder in a cup-shaped member beforehand before the assembly of a cup-shaped member, the workability | operativity at the time of an assembly work improves further. become. Therefore, the gas generator can be assembled very easily.

  In the gas generator according to the present invention, the bottom of the cup portion of the cup-shaped member is preferably configured to be elastically deformable.

  With this configuration, the elastically deformable bottom portion of the cup-shaped member comes into contact with the gas generating agent, so that vibration can be absorbed by elastic deformation of the bottom portion. It is possible to prevent the gas generating agent from being pulverized. Accordingly, it is not necessary to separately provide a cushion material or the like in the combustion chamber, and the number of parts can be reduced.

  In the gas generator according to the present invention, it is preferable that the cup-shaped member is composed of a member made of a metal material or a polymer material.

  By configuring in this way, the seal portion is made of a metal material or a polymer material, so that the seal portion is sandwiched between the housing and the holder and is reliably compressed or distorted. Therefore, the sealing process to be performed between these members is surely realized by the seal portion.

  ADVANTAGE OF THE INVENTION According to this invention, it can be set as a gas generator which can be manufactured cheaply without increasing a number of parts, and can ensure airtightness between a housing and a holder easily.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following embodiments and modifications thereof, the same or corresponding parts are denoted by the same reference numerals in the drawings, and description thereof will not be repeated.

(Embodiment 1)
1A and 1B are diagrams showing an external structure of a cylinder type gas generator according to Embodiment 1 of the present invention. FIG. 1A is a front view and FIG. 1B 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 sectional drawing along the II-II line shown to FIG. 1 (A) and FIG. 1 (B). First, with reference to these FIG. 1 (A), FIG. 1 (B), and FIG. 2, the external structure and internal structure of the cylinder type gas generator 1A in this Embodiment are demonstrated.

  As shown in FIG. 1 (A), FIG. 1 (B), and FIG. 2, a cylinder type gas generator 1A in the present embodiment has a long and substantially cylindrical outer shape, and is closed with a housing 10. The member 12 and the holder 20 are included. The housing 10 is formed of a long cylindrical member having openings at both ends in the axial direction. The closing member 12 is made of a disk-shaped member having a predetermined thickness, and has an annular groove portion 13 for fixing by caulking, which will be described later, on the peripheral surface thereof. The annular groove 13 for caulking and fixing is formed on the peripheral surface of the closing member 12 so as to extend in the circumferential direction. The holder 20 is formed of a cylindrical member having a hollow opening 21 extending in the same direction as the axial direction of the housing 10, and has an annular groove 23 for caulking and fixing described later at a predetermined position on the outer peripheral surface thereof. The annular groove 23 for fixing by caulking is formed on the outer peripheral surface of the holder 20 so as to extend in the circumferential direction.

  The closing member 12 is attached to the housing 10 so as to close one open end of the housing 10. On the other hand, the holder 20 is attached to the other open end of the housing 10. A partition member 14 made of a disk-like plate material is disposed at a predetermined position in the axial direction of the housing 10. The partition member 14 divides the space inside the housing 10 into a combustion chamber 17 and a filter chamber 18 in the axial direction.

  The housing 10, the closing member 12, the partition member 14, and the holder 20 are all made of a metal member such as stainless steel, steel, an aluminum alloy, or a stainless alloy. The housing 10, the closing member 12, the partition member 14 and the holder 20 are connected and fixed by caulking. Specifically, a part of the peripheral wall of the housing 10 corresponding to the annular groove portion 13 provided on the peripheral surface of the closing member 12 in a state in which a part of the closing member 12 is inserted into one opening end of the housing 10. The closure member 12 is caulked and fixed to the housing 10 by reducing the diameter inward in the radial direction (caulking) and engaging with the annular groove 13. One end of the holder 20 is fixed to the other opening end of the housing 10. In a state where the portion is inserted, the peripheral wall of the housing 10 corresponding to the annular groove 23 provided on the outer peripheral surface of the holder 20 is reduced in diameter in the radial direction (caulked) and engaged with the annular groove 23. By doing so, the holder 20 is caulked and fixed to the housing 10. Further, the partition member 14 inserted in a predetermined position of the housing 10 is formed by reducing the diameter of the peripheral walls of both side portions of the housing 10 corresponding to the portion where the partition member 14 is located inward in the radial direction ( The peripheral edge is sandwiched in the axial direction of the housing 10 by a pair of caulking portions formed (by caulking), thereby being fixed to the housing 10 by caulking.

  These caulking fixings are caulking fixings called eight-side caulking that uniformly reduce the diameter of the peripheral wall of the housing 10 toward the inside in the radial direction. By performing this caulking, the first to third caulking portions 10 </ b> A to 10 </ b> C are provided on the peripheral wall of the housing 10. Among these caulking portions, the first caulking portion 10A is a caulking portion for fixing the closing member 12 to the housing 10, and the second caulking portion 10B is a pair of caulking portions for fixing the partition member 14 to the housing 10. The third caulking portion 10 </ b> C is a caulking portion for fixing the holder 20 to the housing 10.

  As shown in FIGS. 1A and 2, a gas outlet 11 is provided on the peripheral wall near the end of the housing 10 on the side where the closing member 12 is attached. The gas ejection ports 11 are holes for ejecting the gas generated inside the cylinder type gas generator 1 </ b> A to the outside, and a plurality of gas ejection ports 11 are provided along the circumferential direction and the axial direction of the housing 10.

  As shown in FIG. 2, an igniter (squib) 30 is disposed in the hollow opening 21 of the holder 20, and the resin molding part 24 is located between the holder 20 and the igniter 30. Yes. The igniter 30 is an ignition device for generating a flame, and includes an ignition unit 31 and a terminal pin 32. The ignition unit 31 includes an igniting agent that ignites during operation and a resistor for burning the igniting agent. The terminal pin 32 is connected to the ignition unit 31 in order to ignite the igniting agent.

  More specifically, the igniter 30 includes a base frame through which the pair of terminal pins 32 are inserted and held, and a squib cup attached to the base frame, and the terminal pins 32 inserted into the squib cup. A resistor (bridge wire) is attached so as to connect the tips of the squib cups, and an igniting agent is filled in the squib cup so as to surround the resistor or in contact with the resistor. Nichrome wire or the like is generally used as the resistor, and ZPP (zirconium / potassium perchlorate), ZWPP (zirconium / tungsten / potassium perchlorate), lead tricinate, or the like is generally used as the igniting agent. The squib cup 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 32. 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 2 milliseconds or less when a nichrome wire is used as the resistor.

  The resin molding part 24 for fixing the igniter 30 to the holder 20 is formed by, for example, insert molding, and the raw material thereof is a thermosetting resin typified by an epoxy resin or the like, polybutylene terephthalate resin, polyethylene A thermoplastic resin represented by terephthalate resin, polyamide resin (for example, nylon 6 or nylon 66), polypropylene sulfide resin, polypropylene oxide resin, or the like can be used.

  As shown in FIG. 2, the combustion chamber 17 and the filter chamber 18 described above are provided in the space inside the cylinder type gas generator 1 </ b> A defined by the housing 10, the closing member 12, and the holder 20. The filter chamber 18 is mainly defined by the housing 10, the closing member 12, and the partition member 14, and is provided at a portion near the opening end of the housing 10 (the left portion in the drawing). On the other hand, the combustion chamber 17 is mainly defined by the housing 10, the partition member 14, and the holder 20, and is provided in a portion near the other opening end of the housing 10 (right portion in the drawing).

  Inside the combustion chamber 17, a cup-shaped member 40, a cushion material 51, a gas generating agent 52 and a porous plate 19 are mainly disposed. On the other hand, a filter 53 is disposed inside the filter chamber 18.

  The cup-shaped member 40 has a bottomed cylindrical shape and is disposed at the end of the combustion chamber 17 on the side where the holder 20 is located. A transfer charge (enhancer) 36 is stored in the transfer charge storage chamber 41a, which is the space inside the cup-shaped member 40.

The explosive charge 36 is ignited by a flame generated by the operation of the igniter 30 and burns to generate hot particles. The charge transfer agent 36 must be capable of reliably starting the combustion of the gas generating agent 52 and is generally composed of a metal powder / oxidant represented by B / KNO ₃ or the like. Things are used. As the charge transfer agent 36, 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.

  The gas generating agent 52 is ignited by the heat particles generated by the combustion of the charge transfer agent 36 ignited by the igniter 30, and generates gas by burning. The gas generating agent 52 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. In addition, as the oxidizing agent, for example, nitrate containing a cation selected from alkali metals, alkaline earth metals, transition metals, and ammonia 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, an organic binder such as a metal salt of carboxymethyl cellulose or a stearate, or an inorganic binder such as synthetic hydroxytalcite or 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 52 includes various shapes such as a granular shape, a pellet shape, a cylindrical shape, and a disk shape. 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 appropriately selected according to the specifications of the airbag apparatus in which the cylinder type gas generator 1A is incorporated. For example, the shape in which the gas generation rate changes with time when the gas generating agent 52 is burned. It is preferable to select an optimal shape according to the specification, such as selecting. In addition to the shape of the gas generating agent 52, 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 52.

  The cushion material 51 is disposed so as to contact the bottom of the bottomed cylindrical cup-shaped member 40 and to contact the gas generating agent 52 accommodated in the combustion chamber 17. The cushion material 51 is provided for the purpose of preventing the gas generating agent 52 made of a molded body from being pulverized by vibration or the like, and a ceramic fiber molded body, foamed silicon, or the like is preferably used. The cushion material 51 is opened or divided by burning of the charge transfer agent 36 during the operation of the cylinder type gas generator 1A, and may be burned out in some cases.

  A perforated plate 19 provided with a plurality of communication holes 19a is disposed at the end of the combustion chamber 17 on the partition member 14 side. The porous plate 19 rectifies the flow of gas released from the combustion chamber 17 during operation, and prevents the gas generating agent 52 accommodated in the combustion chamber 17 from moving to the filter chamber 18 in an unburned state. Is for. Therefore, all of the communication holes 19 a provided in the porous plate 19 are formed smaller than the outer shape of the gas generating agent 52 and are formed smaller than communication holes 14 a described later provided in the partition member 14.

  A communication hole 14 a that communicates between the combustion chamber 17 and the filter chamber 18 during operation is provided at the center of the partition member 14 that partitions the combustion chamber 17 and the filter chamber 18. A seal member 14b is attached to the main surface of the partition member 14 located on the combustion chamber 17 side so as to close the communication hole 14a. As the seal member 14b, an aluminum foil or the like having an adhesive member applied on one side is used. As a result, airtightness between the combustion chamber 17 and the filter chamber 18 during non-operation is ensured, and mixing of moisture and the like into the combustion chamber 17 is prevented.

  A filter 53 is accommodated in the filter chamber 18. The filter chamber 18 communicates with the outside through the gas outlet 11 provided on the peripheral wall of the housing 10 described above.

  The filter 53 is formed of a cylindrical member having a hollow portion 53 a extending in the same direction as the axial direction of the housing 10. By using the filter 53 made of a cylindrical member in this way, the flow resistance of the working gas flowing through the filter chamber 18 during operation can be kept low, and an efficient gas flow can be realized. As the filter 53, for example, a wire made of a metal such as stainless steel or steel, a wire wound around a net, or a material compressed by pressing is used. Specifically, a knitted wire mesh, a plain weave wire mesh, an assembly of crimped metal wires, or the like is used. When the gas generated in the combustion chamber 17 passes through the filter 53, the filter 53 functions as a cooling unit that cools the gas by taking away the high-temperature heat of the gas, and a residue contained in the gas. It also functions as a removing means for removing (slag) and the like.

  A female connector (not shown) is attached to the end of the cylinder type gas generator 1A where the holder 20 is disposed. This female connector is a part to which a male connector of a harness for transmitting a signal from a collision detection means provided separately from the cylinder type gas generator 1A is connected. A shorting clip (not shown) is attached to the female connector as necessary. The shorting clip is attached to prevent the cylinder type gas generator 1A from malfunctioning due to electrostatic discharge or the like during the transportation of the cylinder type gas generator 1A. In the stage, the male connector of the harness is inserted into the female connector, so that the contact with the terminal pin 32 is released.

  Next, the operation | movement at the time of the action | operation of the cylinder type gas generator 1A demonstrated above is demonstrated. When a vehicle equipped with an airbag device incorporating the cylinder-type gas generator 1A according to the present embodiment collides, the collision is detected by a collision detection means 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 31 increases due to combustion of the igniting agent, whereby the igniter 31 is ruptured and the flame flows out of the igniter 31. The explosive charge 36 accommodated in the explosive charge accommodating chamber 41a is ignited and burned by the flame generated by the operation of the igniter 30, and generates a large amount of heat particles. Due to the combustion of the charge transfer agent 36, the pressure in the transfer charge storage chamber 41 a is increased, whereby the cup-shaped member 40 is ruptured, and the above-described heat particles reach the cushion material 51. The hot particles that have reached the cushion material 51 burn the cushion material 51 to open or divide it, whereby the hot particles reach the gas generating agent 52.

  Due to the flowing heat particles, the gas generating agent 52 is ignited and burned to generate a large amount of gas. Due to the combustion of the gas generating agent 52, the pressure in the combustion chamber 17 increases, whereby the sealing of the communication hole 14a by the sealing member 14b is released, and the generated gas flows into the filter chamber 18. The gas that has flowed in flows through the hollow portion 53a of the filter 53, is then cooled to a predetermined temperature via the filter 53, and is ejected from the gas ejection port 11 to the outside of the cylinder type gas generator 1A. . The gas ejected from the gas ejection port 11 is guided into the airbag to inflate and deploy the airbag.

  FIG. 3 is an enlarged cross-sectional view of region III shown in FIG. Next, the structure in the vicinity of the igniter 30 of the cylinder type gas generator 1A in the present embodiment will be described in more detail with reference to FIG.

  As shown in FIG. 3, in the cylinder type gas generator 1 </ b> A according to the present embodiment, the cup-shaped member 40 includes a bottomed cylindrical cup portion 41 that defines a transfer charge storage chamber 41 a, and the cup portion 41. It is comprised by the single member containing the flange part 42 extended continuously from the opening end, and the seal | sticker part 43 further extended from the said flange part 42 further. As described above, the transfer charge 36 is stored in the transfer charge storage chamber 41 a, and the cup-shaped member 40 has the transfer charge 36 stored in the transfer charge storage chamber 41 a facing the ignition portion 31 of the igniter 30. It arrange | positions in the combustion chamber 17 so that it may be in the state which carried out. The flange portion 42 is formed in an annular shape so as to cover the outer peripheral edge portion of the end surface on the combustion chamber 17 side of the holder 20, and the outer peripheral end thereof extends to a position where it abuts on the inner peripheral surface of the housing 10. The seal portion 43 is erected from the outer peripheral end of the flange portion 42, and is interposed between the inner peripheral surface 10 d of the housing 10 and the portion of the outer peripheral surface 22 of the holder 20 near the end surface. The gap between 20 is filled. The seal portion 43 is formed in a cylindrical shape so as to surround the outer peripheral surface 22 of the holder 20, and fills the entire gap in the circumferential direction with a gap between the housing 10 and the holder 20.

  The cup-shaped member 40 is configured by either a member made of a metal material or a polymer material. When the cup-shaped member 40 is formed of a metal material, for example, aluminum, copper, an aluminum alloy, a copper alloy, steel, or the like can be suitably used as the specific material, and in particular, an aluminum foil or a copper foil It is particularly preferred to use a member called Further, when the cup-shaped member 40 is formed of a polymer material, specific materials thereof include, for example, a polyolefin resin such as polypropylene and polyethylene, a hard resin material typified by a polyamide resin, a polyolefin-based material, Soft resin materials typified by polyester-based and polyurethane-based elastomer materials, synthetic resin materials such as silicone resins and fluororesins, and olefin-based, silicone-based and fluorinated rubber materials typified by EPDM can be suitably used. It is.

  A region where the seal portion 43 is located corresponds to a press-fitting region P in which the holder 20 is press-fitted into the housing 10. In the press-fit region P, the holder 20 is press-fitted into the housing 10 so that the holder 20 is attached to the housing 10. In this press-fit region P, the seal portion 43 is interposed between the housing 10 and the holder 20. As a result, an appropriate surface pressure is applied to the seal portion 43. That is, when the cup-shaped member 40 is made of a metal material, the cup-shaped member 40 is distorted by the surface pressure, and the gap between the members, that is, between the housing 10 and the holder 20 is filled by this distortion. It will not occur and the sealing performance will be exhibited. On the other hand, when the cup-shaped member 40 is made of a polymer material, the cup-shaped member 40 is compressed by the surface pressure, and the space between these members, that is, between the housing 10 and the holder 20 is filled by this compression. As a result, no gap is generated, and sealing performance is exhibited. In order to realize the above structure, when the holder 20 is press-fitted into the housing 10, the cup-shaped member 40 is attached to the holder 20 in advance, and the outer peripheral surface of the holder 20 is covered with the seal portion 43 of the cup-shaped member 40. Just do it.

  On the other hand, a caulking fixing region Q is located in a portion closer to the opening end on the side where the holder 20 of the housing 10 is inserted than the press-fitting region P described above. In the caulking and fixing region Q, a force is applied to the peripheral wall portion of the housing 10 in the direction of arrow A in the figure, so that the peripheral wall portion of the housing 10 is directed toward the annular groove portion 23 provided on the outer peripheral surface 22 of the holder 20. As a result, the peripheral wall portion of the housing 10 is reduced in diameter (caulked) along the outer peripheral surface 22 of the holder 20 to be plastically deformed, and the caulking portion 10C including the reduced diameter portions 10a to 10c is formed into an annular groove portion. 23 to be engaged. As a result, the holder 20 is securely fixed to the housing 10 together with the press-fitting in the press-fitting region P described above. Here, each of the reduced diameter portions 10a to 10c is in direct contact with the outer peripheral surface 22 of the holder 20, thereby ensuring a breakdown voltage during operation (that is, preventing gas leakage). .

  By using the cylinder-type gas generator 1A in the present embodiment described above, a gap between the housing 10 and the holder 20 is provided by the seal portion 43 that is a part of the cup-shaped member 40 in which the transfer charge 36 is accommodated. Will be filled, and the sealing process in the said part will be implement | achieved. Therefore, the combustion chamber 17 can be easily and airtightly sealed without increasing the number of parts, and it is possible to prevent the gas generating agent 52 from absorbing moisture due to outside air containing moisture entering the combustion chamber 17. It becomes. Therefore, a highly reliable cylinder type gas generator that can be manufactured easily and at low cost can be obtained.

  When the cup-shaped member 40 is made of a metal material, the sealing performance is ensured by the distortion of the seal portion 43 after assembly as described above. For this reason, the thickness before assembly of the seal portion 43 is preferably adjusted to approximately 0.05 mm to 0.8 mm, although it varies slightly depending on the specific material. As the amount, it is preferable that the strain value is set to 0.2% or more with respect to the initial state. When the thickness before assembling of the seal portion 43 and the strain value after assembling satisfy the above conditions, the sealing performance at the portion is stably maintained over a long period of time.

  Further, when the cup-shaped member 40 is made of a polymer material, the sealing portion 43 is compressed after the assembly as described above, so that the sealing performance is ensured. Therefore, the thickness before assembly of the seal portion is preferably adjusted to approximately 0.005 mm to 2.0 mm, although it varies slightly depending on the specific material, and the compression rate after assembly Is preferably set to 8% or more and 60% or less. When the thickness before assembling of the seal portion 43 and the compression rate after assembling satisfy the above conditions, the sealing performance at the portion is stably maintained over a long period of time.

  As shown in FIG. 3, also in the press-fitting region P, the housing 10 may be caulked in the direction of arrow B in the drawing after the holder 20 is press-fitted into the housing 10. By doing so, the surface pressure is surely acted by the seal portion 43 interposed between the housing 10 and the holder 20, so that the sealing performance at that portion can be made more reliable.

  4 to 8 are enlarged sectional views showing modifications of the cylinder type gas generator in the above-described embodiment. Next, cylinder type gas generators 1B to 1F according to first to fifth modifications of the present embodiment will be described with reference to these drawings.

  In the cylinder type gas generators 1B to 1D according to the first to third modifications shown in FIGS. 4 to 6, the seal portion 43 extending from the cup portion 41 of the cup-shaped member 40 reaches the press-fitting region P. In addition, it reaches the caulking fixing region Q located further on the end side. More specifically, in the cylinder-type gas generator 1B according to the first modification shown in FIG. 4, the portion where the reduced diameter portion 10a of the caulking fixing region Q is located where the seal portion 43 is adjacent to the press-fitting region P (ie, , The caulking portion 10C of the housing 10 to the combustion chamber 17 side), and the seal portion is formed by the reduced diameter portion 10a and the annular groove portion 23 corresponding to the portion where the reduced diameter portion 10a is located. 43 is sandwiched. Further, in the cylinder type gas generator 1C according to the second modified example shown in FIG. 5, the portion where the reduced diameter portion 10b adjacent to the reduced diameter portion 10a of the caulking fixing region Q is positioned (that is, the housing) 10, and the seal portion 43 is sandwiched between the reduced diameter portions 10 a and 10 b and the annular groove portion 23 corresponding to the portion where the reduced diameter portions 10 a and 10 b are located. Yes. Further, in the cylinder type gas generator 1D according to the third modification shown in FIG. 6, the seal portion 43 is a portion where the reduced diameter portion 10c adjacent to the reduced diameter portion 10b of the caulking fixed region Q is located (that is, the housing). 10 of the caulking portion 10C on the opening end side) and is sealed by the reduced diameter portions 10a to 10c and the annular groove portion 23 corresponding to the portion where the reduced diameter portions 10a to 10c are located. Part 43 is sandwiched.

  In such a configuration, when the caulking process is performed in the caulking fixing region Q, the surface pressure is surely applied to the seal portion 43 interposed between the housing 10 and the holder 20. Not only the region P but also the caulking fixed region Q is secured. Therefore, it becomes possible to obtain better sealing characteristics.

  In the cylinder type gas generators 1E and 1F according to the fourth and fifth modifications shown in FIGS. 7 and 8, the cup-shaped member 40 provided in the cylinder type gas generator 1A in the above-described embodiment is used. The structure which abolished the flange part 42 is employ | adopted. In the case of such a configuration, the shape of the cup-shaped member 40 is further simplified, so that a cylinder type gas generator can be manufactured at a lower cost. Whether or not the flange portion 42 is provided in the cup-shaped member 40 may be determined according to the amount of the transfer charge 36 to be accommodated in the cup-shaped member 40 and the inner diameter of the housing 10.

  Further, in the cylinder type gas generator 1F shown in FIG. 8, the bottom of the bottomed cylindrical cup portion 41 of the cup-shaped member 40 has a dome shape protruding toward the space in which the gas generating agent 52 is accommodated. A configuration in which the cushion material 51 provided in the cylinder type gas generator 1A in the present embodiment is eliminated is employed. With such a configuration, the dome-shaped bottom portion of the cup-shaped member 40 and the gas generating agent 52 are in direct contact with each other, but the bottom portion is elastically deformed by configuring the bottom portion so as to be elastically deformable. As a result, vibration can be absorbed, and the gas generating agent 52 can be prevented from being crushed by vibration or the like. Therefore, it is not necessary to separately arrange the cushion material 51 and the like in the combustion chamber 17, and the number of parts can be further reduced.

(Embodiment 2)
FIG. 9 is an enlarged cross-sectional view showing the internal structure of the cylinder type gas generator according to Embodiment 2 of the present invention. Below, with reference to this FIG. 9, the sealing structure of the cylinder type gas generator 1G in this Embodiment is demonstrated in detail.

  As shown in FIG. 9, the cylinder type gas generator 1G in the present embodiment does not include the press-fitting region P unlike the cylinder type gas generator 1A in the first embodiment. That is, the holder 20 is inserted into the opening end of the housing 10, and the peripheral wall of the housing 10 is reduced (caulked) toward the annular groove portion 23 provided on the outer peripheral surface 22 of the holder 20 in the caulking fixing region Q. Fixed only by. Of the portion where the inner peripheral surface 10d of the housing 10 and the outer peripheral surface 22 of the holder 20 face each other, the surface pressure is not applied to the seal portion 43 in the portion located on the combustion chamber 17 side of the caulking fixing region Q. In addition, the sealability is not ensured in this part. However, the seal portion 43 reaches the portion where the reduced diameter portion 10a of the caulking fixing region Q is located (that is, the inclined portion located on the combustion chamber 17 side of the caulking portion 10C of the housing 10), and the reduced diameter portion 10a. The seal portion 43 is sandwiched between the annular groove portion 23 corresponding to the portion where the reduced diameter portion 10a is located.

  Even in such a configuration, when the caulking process is performed in the caulking fixing region Q, the surface pressure is surely applied to the seal portion 43 interposed between the housing 10 and the holder 20. Even if the press-fitting region P provided in the first embodiment is not provided, good sealing performance is secured in the caulking fixing region Q.

(Embodiment 3)
FIG. 10 is an enlarged cross-sectional view showing the internal structure of the cylinder type gas generator according to Embodiment 3 of the present invention. Below, with reference to this FIG. 10, the seal structure of the cylinder type gas generator 1H in this Embodiment is demonstrated in detail.

  As shown in FIG. 10, the cylinder type gas generator 1H in the present embodiment includes a press-fitting region P and a caulking fixing region Q, similarly to the cylinder type gas generator 1A in the first embodiment. In addition to this, the cylinder type gas generator 1H in the present embodiment further includes a pressure contact region R. The pressure contact region R is positioned closer to the opening end of the housing 10 than the caulking fixing region Q (opening end on the side where the holder 21 is inserted). In the pressure contact region R, the inner peripheral surface 10d of the housing 10 and the outer peripheral surface 23 of the holder 21 are in direct contact with each other by caulking the housing 10 in the direction of the arrow C in the drawing to form the caulking portion 10D. The pressure contact state between 10D and the holder 21 is maintained. The seal portion 43 is interposed between the housing 10 and the holder 21 in the press-fitting region P and the caulking fixing region Q, and is not interposed between them in the press-contact region R.

  With this configuration, in addition to the effects described in the first embodiment of the present invention, a high pressure resistance is maintained in the pressure contact region R where the housing 10 and the holder 20 are in direct contact with each other. It is possible to provide a highly reliable cylinder type gas generator that does not cause gas leakage even at times. In addition, although the case where the press-contact area | region R was formed by crimping the housing 10 was illustrated in the above, the press-contact area | region R can be formed by performing press-fit etc. besides this.

(Embodiment 4)
FIG. 11 is an enlarged cross-sectional view showing the internal structure of the cylinder type gas generator in Embodiment 4 of the present invention. Below, with reference to this FIG. 11, the cylinder type gas generator 1I in this Embodiment is demonstrated in detail.

  As shown in FIG. 11, the cylinder type gas generator 1I in the present embodiment is different from the cylinder type gas generator 1A in the first embodiment in the structure of the cup-shaped member 40. Specifically, in the cylinder type gas generator 1A in the first embodiment described above, the cup-shaped member 40 is configured by a single member, but in the cylinder type gas generator 1I in the present embodiment, The cup-shaped member 40 is configured by combining two members. More specifically, one of the members constituting the cup-shaped member 40 is extended from the cup portion 41 that defines the charge transfer chamber 41a, the flange portion 42 that extends from the cup portion 41, and the flange portion 42. The other member includes a lid portion 47 that closes the open end of the cup portion 41. The lid portion 47 covers the end surface on the combustion chamber 17 side of the holder 20 and the upper end portion on the combustion chamber 17 side of the igniter 30 of the igniter 30, and the outer peripheral edge portion thereof is overlapped with the flange portion 42. 42 is bonded or welded. Thereby, the explosive charge storage chamber 41 a is maintained in a state of being sealed by the cup portion 41 and the lid portion 47. The seal portion 43 is erected from the outer peripheral end of the flange portion 42 and is interposed between the housing 10 and the holder 20 in the same manner as the cylinder type gas generator 1A in the first embodiment described above.

  In the case of such a configuration, the transfer charge 36 can be sealed in the cup-shaped member 40 in advance before the cup-shaped member 40 is assembled. There is no fear of the transfer charge 36 falling down, and there is no fear that the transfer charge 36 will be mixed into the combustion chamber 17, so that the handling is dramatically improved and the assembly work is greatly facilitated. Therefore, it can be set as the cylinder type gas generator which can perform an assembly | attachment operation | work very easily.

  12 and 13 are enlarged cross-sectional views showing modifications of the cylinder type gas generator in the present embodiment described above. Next, cylinder type gas generators 1J and 1K according to first and second modifications of the present embodiment will be described with reference to these drawings.

  As shown in FIGS. 12 and 13, in the cylinder type gas generators 1 </ b> J and 1 </ b> K according to the first and second modified examples, the cup-shaped member is similar to the cylinder type gas generator 1 </ b> I in the present embodiment described above. 40 is configured by combining two members.

  As shown in FIG. 12, in the cylinder-type gas generator 1J according to the first modified example, one member constituting the cup-shaped member 40 includes a cup portion 41 that defines a transfer charge storage chamber 41a, and the cup portion. The other member includes a lid portion 47 that closes the opening end of the cup portion 41, and a seal portion 48 that extends from the lid portion 47. . The lid portion 47 covers the end surface on the combustion chamber 17 side of the holder 20 and the upper end portion on the combustion chamber 17 side of the igniter 30 of the igniter 30, and the outer peripheral edge portion thereof is overlapped with the flange portion 42. 42 is bonded or welded. Thereby, the explosive charge storage chamber 41 a is maintained in a state of being sealed by the cup portion 41 and the lid portion 47. The seal portion 48 is erected from the outer peripheral end of the lid portion 47 and is interposed between the housing 10 and the holder 20.

  On the other hand, as shown in FIG. 13, in the cylinder type gas generator 1K according to the second modified example, one member constituting the cup-shaped member 40 includes a cup portion 41 that defines a transfer charge storage chamber 41a, the cup A flange portion 42 extending from the portion 41 and a seal portion 43 extending from the flange portion 42, and the other member includes a lid portion 47 that closes the open end of the cup portion 41, and the lid portion A seal 48 extending from 47 is included. The lid portion 47 covers the end surface on the combustion chamber 17 side of the holder 20 and the upper end portion on the combustion chamber 17 side of the igniter 30 of the igniter 30, and the outer peripheral edge portion thereof is overlapped with the flange portion 42. 42 is bonded or welded. Thereby, the explosive charge storage chamber 41 a is maintained in a state of being sealed by the cup portion 41 and the lid portion 47. The seal portions 43 and 48 are erected from the outer peripheral ends of the flange portion 42 and the lid portion 47, respectively, and are interposed between the housing 10 and the holder 20. These seal portions 43 and 48 may be integrated by bonding or welding, or such integration may not be performed.

  Even when the configuration as shown in FIG. 12 and FIG. 13 described above is employed, the same effect as that obtained when the configuration as in the cylinder type gas generator 1I in the present embodiment described above is employed can be obtained. That is, by adopting the above-described configuration, it becomes possible to seal the charge transfer agent 36 in the cup-shaped member 40 in advance before the cup-shaped member 40 is assembled. It is possible to obtain the effect of greatly improving and greatly simplifying the assembly work.

(Embodiment 5)
FIG. 14 is an enlarged cross-sectional view showing the internal structure of the cylinder type gas generator in the fifth embodiment of the present invention. Below, with reference to this FIG. 14, the cylinder type gas generator 1L in this Embodiment is demonstrated in detail.

  In the cylinder type gas generators 1A to 1K according to the above-described first to fourth embodiments and modifications thereof, a structure in which the igniter 30 is fixed to the holder 20 via the resin molding portion 24 formed by injection molding. The case where it was adopted was described as an example. However, it is also possible to fix the igniter 30 to the holder 20 by other methods. In that case, the present invention can also be applied, and one specific example is shown below.

  As shown in FIG. 14, in the cylinder type gas generator 1L in the present embodiment, the igniter 30 is fixed to the holder 20 by caulking. More specifically, the holder 20 has a pedestal portion 25 provided in the hollow opening 21 and a caulking portion 26 provided on the inner peripheral edge of the end surface on the combustion chamber 17 side near the hollow opening 21. The igniter 30 is inserted into the hollow opening 21 of the holder 20 from the combustion chamber 17 side, and the caulking portion 26 is caulked inward with the lower end of the ignition portion 31 supported by the pedestal portion 25. It is clamped and fixed to the holder 20. A seal member 38 such as an O-ring is interposed between the base portion 25 of the holder 20 and the ignition portion 31 of the igniter 30, thereby ensuring airtightness between the transfer charge storage chamber 41 a and the outside. Yes. Also in this configuration, the seal structure 43 as employed in the cylinder type gas generator 1A in the above-described first embodiment, that is, the seal portion 43 formed by extending a part of the cup-shaped member 40 is provided with the housing 10 and the holder 20. It is possible to adopt a configuration in which a sealing property between the housing 10 and the holder 20 is ensured by being interposed between the two.

  The characteristic configurations of the cylinder type gas generators 1A to 1L according to the first to fifth embodiments of the present invention and the modifications thereof described above can be combined with each other.

  As described above, the above-described embodiment and its modifications disclosed herein are illustrative in all respects and are not restrictive. The technical scope of the present invention is defined by the claims, and includes all modifications within the meaning and scope equivalent to the description of the claims.

It is a figure which shows the external appearance structure of the cylinder type gas generator in Embodiment 1 of this invention, (A) is a front view, (B) is a right view. It is a figure which shows the internal structure of the cylinder type gas generator in Embodiment 1 of this invention, and is sectional drawing along the II-II line shown to FIG. 1 (A) and FIG. 1 (B). It is an expanded sectional view of the area | region III shown in FIG. It is an expanded sectional view which shows the internal structure of the cylinder type gas generator which concerns on the 1st modification of Embodiment 1 of this invention. It is an expanded sectional view which shows the internal structure of the cylinder type gas generator which concerns on the 2nd modification of Embodiment 1 of this invention. It is an expanded sectional view which shows the internal structure of the cylinder type gas generator which concerns on the 3rd modification of Embodiment 1 of this invention. It is an expanded sectional view which shows the internal structure of the cylinder type gas generator which concerns on the 4th modification of Embodiment 1 of this invention. It is an expanded sectional view which shows the internal structure of the cylinder type gas generator which concerns on the 5th modification of Embodiment 1 of this invention. It is an expanded sectional view which shows the internal structure of the cylinder type gas generator in Embodiment 2 of this invention. It is an expanded sectional view which shows the internal structure of the cylinder type gas generator in Embodiment 3 of this invention. It is an expanded sectional view which shows the internal structure of the cylinder type gas generator in Embodiment 4 of this invention. It is an expanded sectional view which shows the internal structure of the cylinder type gas generator which concerns on the 1st modification of Embodiment 4 of this invention. It is an expanded sectional view which shows the internal structure of the cylinder type gas generator which concerns on the 2nd modification of Embodiment 4 of this invention. It is an expanded sectional view which shows the internal structure of the cylinder type gas generator in Embodiment 5 of this invention.

Explanation of symbols

  1A to 1L Cylinder type gas generator, 10 housing, 10A to 10D crimped portion, 10a to 10c reduced diameter portion, 10d inner peripheral surface, 11 gas ejection port, 12 closing member, 13 annular groove portion, 14 partition member, 14a communication hole 14b seal member, 17 combustion chamber, 18 filter chamber, 19 porous plate, 19a communication hole, 20 holder, 21 hollow opening, 22 outer peripheral surface, 23 annular groove, 24 resin molding portion, 25 pedestal portion, 26 caulking portion, 30 igniter, 31 ignition part, 32 terminal pin, 36 transfer powder, 38 seal member, 40 cup-shaped member, 41 cup part, 41a transfer powder storage chamber, 42 flange part, 43, 48 seal part, 47 lid part, 51 Cushion material, 52 gas generating agent, 53 filter, 53a hollow part, P press-fitting area, Q caulking fixing area, R pressure welding Pass.

Claims (8)

A long cylindrical metal housing containing therein a combustion chamber containing a gas generating agent;
A hollow opening portion attached to the housing in a state where at least a part thereof is inserted into an opening end in the axial direction of the housing so as to face the combustion chamber, and extending in a direction parallel to the axial direction of the housing. A metal holder including,
An igniter including an igniter containing an igniting agent, the igniter being disposed on the combustion chamber side and disposed in the hollow opening and fixed to the holder;
Defining a transfer charge storage chamber, and comprising a cup-shaped member disposed in the combustion chamber so that the transfer charge stored in the transfer charge storage chamber faces the ignition unit,
The cup-shaped member includes a seal portion that extends from a portion that defines the explosive charge storage chamber, and that is interposed between the housing and the holder and seals a gap therebetween.
The holder is fixed to the housing by caulking the peripheral wall of the housing of a portion corresponding to at least a part of the portion in which the holder is inserted, radially inward,
The seal portion is interposed between the housing and the holder at a portion corresponding to a portion where the housing is caulked ,
A gas generator, wherein a pressure contact portion in which an inner peripheral surface of the housing and an outer peripheral surface of the holder are in direct contact is provided in a part of a portion where the holder is inserted into the housing . The holder has an annular groove extending in a circumferential direction on an outer peripheral surface of a portion corresponding to a portion where the housing is caulked,
The gas generator according to claim 1, wherein a caulked portion of the housing is engaged with the annular groove. The portion of the holder that is inserted into the housing includes a portion that is press-fitted into the open end of the housing,
The gas generator according to claim 1 or 2, wherein the seal portion is interposed between the housing and the holder at a portion corresponding to a portion into which the holder is press-fitted. The gas generator according to any one of claims 1 to 3, wherein the press-contact portion is formed by caulking a peripheral wall of the housing toward a radially inner side. The cup-shaped member includes a bottomed cylindrical cup portion that defines the transfer charge storage chamber,
The gas generator according to any one of claims 1 to 4 , wherein the seal portion extends continuously from an open end of the cup portion. The cup-shaped member includes a bottomed cylindrical cup portion that defines the explosive charge storage chamber, and a lid portion that closes an open end of the cup portion,
The gas generator according to any one of claims 1 to 4 , wherein the explosive charge storage chamber is sealed by the cup portion and the lid portion. The gas generator according to claim 5 or 6 , wherein the cup-shaped member is configured such that a bottom portion of the cup portion is elastically deformable. The gas generator according to any one of claims 1 to 7 , wherein the cup-shaped member is formed of a member made of a metal material or a polymer material.

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