JP6489722B2 - 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 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 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 in addition to 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. 11-245760 (Patent Document 1), Japanese Patent No. 4809444 (Patent Document 2), and Japanese Patent Application Laid-Open No. 2010-260387. There exists a gazette (patent document 3) etc. In the cylinder type gas generators disclosed in Patent Documents 1 to 3, an igniter and a charge transfer agent are arranged 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 combustion chamber in which working gas is generated by burning the gas generating agent and containing the agent is provided, and a filter chamber in which a filter is accommodated and a gas outlet are provided at the other end in the axial direction.

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

Among these, Patent Document 1 discloses a cylinder-type gas generator in which a combustion chamber (combustion chamber) is partitioned by a substantially cylindrical tubular screen (compartment member), and a gas generating agent is contained therein. (In particular, see FIG. 1 of Patent Document 1). A radially outer surface of the combustion chamber (combustion chamber) has a substantially cylindrical plenum (plenum chamber) formed between the outer surface of the tubular screen and the inner surface of the housing, and a combustion chamber (combustion chamber) The working gas generated in step 1 passes through the plenum (plenum chamber), then passes through the filter chamber (cooling chamber), and finally the working gas is released from the outlet opening (gas ejection hole) to the outside of the gas generator. . Of the working gas and the particulate matter generated by the combustion of the gas generating agent when the working gas passes through the plenum (plenum chamber), the particulate matter is deposited and collected on the inner surface of the housing.

Patent Document 2 discloses a gas generator that includes an inner chamber (combustion chamber) and a drug cylinder (partition member) and that performs gas-tight connection with a sealing element. The sealing element is deformed by pressing, allowing a gas tight connection. Patent Document 3 discloses a gas generator including a partition member having a working gas generation chamber (combustion chamber) and a substantially cylindrical space for the working gas to pass therethrough. The gas generating agent and the partition member are accommodated in a first closed container (closed container).

Japanese Patent Laid-Open No. 11-245760 Japanese Patent No. 4809444 JP 2010-260387 A

  In the cylinder type gas generator, there is an extremely strong demand for improvement in mountability on a vehicle or the like, and the reduction in size and weight is an important issue. Therefore, in recent years, attempts have been made to change relatively heavy parts such as a housing and a filter, which are main components of a cylinder type gas generator, to small and light parts. For example, attempts have been made to reduce the number of filter members for cooling the working gas generated by the combustion of the gas generating agent and removing the particulate matter, which is described in Patent Document 1 as well. .

  Here, in recent years, non-azide gas generating agents have become widespread as gas generating agents used in gas generators. When this non-azide gas generating agent is used, it has a characteristic of generating a relatively large amount of gas, so that it can be used favorably for an airbag device, but a gas generating agent of another composition is used. As a result, problems such as poor ignitability compared to the above case, and problems such as needing to be placed in a high-pressure environment in order to perform stable combustion occur. Therefore, in order to reduce the size and weight of the housing of the cylinder type gas generator, it is necessary to take these points into consideration.

  In addition, the non-azide-based gas generating agent often has a hygroscopic property as an organic compound or an inorganic compound constituting the non-azide gas generating agent, and if they absorb moisture, a phenomenon different from the originally designed combustion characteristic. As a result, there is a concern that the optimal occupant protection performance of the airbag cannot be exhibited. In order to prevent these, the explosives used in the inflator, including the gas generating agent, are preferably held in the gas generator in a sealed (sealed) form.

  As described above, other requirements are met while achieving the challenges of reducing the size and weight of the cylinder-type gas generator (particularly, reducing the diameter and weight), ignitability of non-azide gas generants, combustion stability, and holding the seal. It is difficult to design a gas generator to meet the requirements.

  Accordingly, the present invention has been made to solve the above-described problems, and an object of the present invention is to provide a small and lightweight gas generator that can stably obtain desired output characteristics.

A gas generator according to the present invention operates by being assembled with a gas generating agent that generates gas by combustion, a long cylindrical housing in which both axial ends are closed, and one axial end of the housing. An igniter that generates a flame for directly or indirectly burning the gas generating agent, and a part of the gas generating agent, or a part of the gas generating agent, which is located inside the housing, In a gas generator having at least a partition member to be formed and a sealed container for containing and sealing at least the gas generating agent as constituent elements,
The thickness of the housing in the radial direction of the cylindrical portion is adjusted to be thicker than the thickness of the sealed container in the radial direction of the cylindrical portion, and the gas generating agent and the partition member are accommodated in the sealed container and sealed. It is characterized by.

  In the gas generator according to the present invention, it is preferable that the thermal conductivity at 0 ° C. of the substance constituting the sealed container is larger than the thermal conductivity of the substance constituting the housing.

  In the gas generator according to the present invention, the partition member includes an enlarged diameter portion whose at least one end side is substantially the same diameter as the inner diameter of the sealed container, the radially inner surface of the sealed container, and the partition member. And a gas passage hole through which the gas generated from the gas generating agent flows into the gap from the inside of the partition member. It is preferable to have a deformation part located between the part and the enlarged diameter part and the main body part.

  In the gas generator according to the present invention, it is preferable that the enlarged diameter portion is provided at both ends of the partition member.

  The gas generator according to the present invention includes a filter chamber in which a filter is accommodated at an end portion opposite to the igniter assembled at one end portion in the axial direction of the housing, and a space inside the housing. It is preferable to further include a partition member that is partitioned into the filter chamber and the gap in the axial direction and has an opening for allowing gas to pass through the gap to the filter chamber.

  In the gas generator based on the said invention, it is preferable that a cushion member is further included in the said airtight container.

  In the gas generator according to the present invention, the outer shape of the cushion member is substantially the same as the inner diameter of the sealed container, and the gas generating agent is interposed between the cushion member and one end of the partition member. It is preferable to have a layer.

  ADVANTAGE OF THE INVENTION According to this invention, it can be set as the gas generator reduced in size and weight which can obtain a desired output characteristic stably. More specifically, a partition member is arranged inside the sealed container, and the thickness of the sealed container is made thinner than that of the housing, or the material of the sealed container is made of a material whose thermal conductivity at 0 ° C. is larger than that of the housing. By selecting, cooling of the working gas generated by the combustion of the gas generating agent and removal of the particulate matter are performed more effectively. In addition to the function that the sealed container seals the gas generating agent, the effect of promoting the stable combustion of the gas generating agent by increasing the pressure in the sealed container in the early stage of combustion of the gas generator is also achieved.

It is a schematic cross section of the cylinder type gas generator in Embodiment 1 of the present invention. It is an A section enlarged schematic sectional view of a cylinder type gas generator in Embodiment 1 of the present invention. It is a B section expansion schematic sectional view of the cylinder type gas generator in Embodiment 1 of the present invention. It is a schematic cross section of the cylinder type gas generator in Embodiment 2 of the present invention. It is C section expansion schematic sectional drawing of the cylinder type gas generator in Embodiment 2 of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The embodiment described below exemplifies a case where the present invention is applied to a so-called cylinder type gas generator suitably incorporated in a side airbag device or the like.

  FIG. 1 is a schematic cross-sectional view showing the internal structure of a cylinder type gas generator in an embodiment of the present invention. Hereinafter, the internal structure of the cylinder type gas generator in the present embodiment will be described with reference to FIG. 1 and FIG. 3 which is an enlarged sectional view.

As shown in FIG. 1, a cylinder type gas generator 1 </ b> A in the present embodiment has a long and substantially cylindrical outer shape, and includes a housing 10 and a holder 20. The housing 10 is composed of a long cylindrical member having an opening at least at one end in the axial direction.
As shown in FIG. 1, the holder 20 is fixed to the housing 10 so as to close the cylindrical portion of the housing 10. 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 an annular groove 23 for caulking and fixing described later is provided at a predetermined position on the outer peripheral surface of the holder 20. A caulking portion 26 is provided at an end portion facing the space. The annular groove 23 for caulking and fixing is formed on the outer peripheral surface of the holder 20 so as to extend in the circumferential direction. On the other hand, the caulking portion 26 is a portion for fixing the igniter 30 as described later. The holder 20 is attached to the open end of the housing 10.

  The housing 10 and the holder 20 are preferably configured by metallic members such as stainless steel, steel, aluminum alloy, and stainless alloy. Further, the housing 10 is formed by pressing one of a rolled metal plate represented by SPCE and a metal press-molded product formed into a bottomed cylindrical shape, or an axial end portion of an electric resistance welded tube represented by STKM. You may be comprised with the metal molded product shape | molded by the closing process and the bottomed cylindrical shape. In particular, when the housing 10 is configured as a press-formed product of a rolled steel plate or a molded product of an electric resistance welded tube, the housing 10 can be easily and inexpensively compared with a case where a metal member such as stainless steel or steel is used. It can be formed and can be significantly reduced in weight. In addition, as a manufacturing method of the holder 20, a metal bar is cut out and then made into a desired shape by cutting, or a forging process is performed up to an outline shape, and a detailed shape is cut into a desired shape. A method is mentioned. The housing 10 and the holder 20 are connected and fixed by caulking. Specifically, in a state where a part of the holder 20 is inserted into the opening end of the housing 10, the peripheral wall of the housing 10 corresponding to the annular groove 23 provided on the outer peripheral surface of the holder 20 is radially inward. The holder 20 is caulked and fixed to the housing 10 by reducing the diameter (caulking) and engaging with the annular groove 23. 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.

  As shown in FIG. 1, a gas outlet 11 is provided on the peripheral wall near the opposite end of the housing 10 to which the holder 20 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. 1, an igniter 30 as an igniting means existing at one end of the housing in the axial direction (that is, a portion near the holder 20) generates a flame for burning a granular gas generating agent 52 described later. It is for generating.

  The igniter 30 is inserted into the hollow opening 21 of the holder 20 and fixed by caulking. The holder 20 has a caulking portion 26 at an end facing the space inside the housing, and an igniter 30 is inserted into the hollow opening 21 via an O-ring 27 and applied to the holder 20. By caulking the caulking portion 26 in the clamped state, the igniter 30 is sandwiched by the holder 20 and the igniter 30 is fixed to the holder 20. Another suitable form is a known method in which an igniter and a holder are integrated by injection molding with a thermoplastic resin or the like.

More specifically, the igniter 30 includes a base frame (not shown) through which the pair of terminal pins 32 are inserted and held, and a squib cup (not shown) attached on the base frame, and is inserted into the squib cup. A resistor (bridge wire) (not shown) is attached so as to connect the tips of the terminal pins 32 of the base frame, and an igniting agent (not shown) is placed in the squib cup so as to surround the resistor or to contact the resistor. Filled, and filled with explosives as needed. 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. Generally, a composition composed of a metal powder / oxidizer represented by B / KNO ₃ or the like, a composition composed of titanium hydride / potassium perchlorate, or B / 5-aminotetrazole / potassium nitrate / molybdenum trioxide. A composition or the like is used. The type and amount of explosives accommodated in the squib cup are appropriately adjusted so as to be necessary and sufficient for burning the gas generating agent 52 while satisfying the ignition sensitivity required for the igniter. The necessary amount of igniting agent is mainly accommodated in the squib cup to satisfy the ignition sensitivity required for the igniter, and the necessary amount of igniting agent is accommodated in the squib cup mainly for burning the gas generating agent 52. Is done. In this sense, if the gas generating agent 52 can be burned in addition to the ignition sensitivity described above, it is not necessary to store the transfer 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 ignition powder and the transfer powder. 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.

As shown in FIG. 1, in the space inside the housing 10, a sealed container 40, a combustion chamber 17 in which a gas generating agent located inside the sealed container is accommodated, a filter chamber 18, the combustion chamber 17 and the sealed container 40. A gap 19 exists between the combustion chamber 17 and the gap 19 by a partition member 35 to be described later. The combustion chamber 17 is located at a substantially central portion of the housing 10 in the axial direction, and an igniter 30, a cushion material 51, and a gas generating agent 52, which will be described later, are accommodated therein.
The filter chamber 18 is located at the other end portion in the axial direction of the housing 10 (that is, the closed portion side of the housing 10), and a filter 53 described later is accommodated therein. Further, a gas generating agent 52, a partition member 35, and a partition member 61 are disposed in the sealed container 40. In the axial direction of the housing 10, the filter chambers 18 are arranged in parallel with the sealed container 40.

As shown in FIG. 2, the partition member 35 includes a first enlarged diameter portion 36, a deformable portion 37, a main body portion 38, and a first opening portion 39, and has a substantially cylindrical shape. Here, the first enlarged diameter portion 36 is configured on the igniter 30 side, and the deformable portion 37 connects the first enlarged diameter portion 36 and the main body portion 38. The deformation part 37 is configured to gradually increase in diameter toward the igniter side, and has a tapered shape here. Moreover, the 1st enlarged diameter part 36 is in contact with the internal peripheral surface of the airtight container 40 mentioned later. The first enlarged diameter portion 36 is provided around the igniter side end of the sealed container 40 to be described later, and the combustion chamber 17 for storing the gas generating agent includes the main body portion 38, the deformable portion 37, and the first enlarged diameter portion. 36 has a portion defined by the inner peripheral surface of 36 and a portion defined by the inner peripheral surface of the sealed container 40. With this configuration, when the partition member 35 is disposed, a gap is generated in the radial direction of the housing by the deformable portion 37, so that the gap 19 is reliably set between the inner peripheral surface of the sealed container 40 and the main body portion 38. can do. Moreover, the partition member 35 can be comprised with metal members, such as stainless steel, steel, an aluminum alloy, and a stainless alloy. Moreover, as a suitable manufacturing method of a division member, it can be set as a desired shape by performing a press work to plate-shaped metal material.
As shown in FIG. 3, a plurality of the first openings 39 are provided on the peripheral wall of the main body 38 of the partition member 35. The plurality of first openings 39 that are present are smaller than the outer shape of the gas generating agent 52, and several rows are provided in the circumferential wall of the partition member 35 so as to form an opening row along the circumferential direction.
The total area A1, which is the sum of the opening areas of the plurality of first openings 39, is sufficiently large so as not to hinder gas flow. Specifically, the total area A1 is the opening area of the second opening 65 of the partition member 61. The total area A2 is larger than the total area A2, which is the sum, and is larger than the total area A3, which is the sum of the opening areas of the plurality of jet outlets 11 existing on the peripheral wall of the housing.
The partition member 35 is open on the filter chamber 18 side, and a partition member 61 described later is fitted therein, and the opening end is closed by the bottom of the partition member 61.

The sealed container 40 is composed of a sealed member 41 and a cover member 42, and is disposed so as to face the igniter 30. A partition member 35, a gas generating agent 52, and a partition member 61 are disposed therein, As a material of the sealing member 41 and the cover member 42, a metal member formed by pressing a metal thin plate (foil) such as copper, aluminum, brass, copper alloy, or aluminum alloy can be used. The sealing member 41 is formed in a cup shape, and includes a cylindrical part and a sealing member bottom part 43 extending from the cylindrical part, and an end of the sealing member 41 opposite to the sealing member bottom part 43 is open. It is an end and the cover part 42 is inserted. Here, the thickness of the housing 10 in the radial direction of the cylindrical portion is adjusted to be larger than the thickness of the sealing member 41 in the radial direction of the cylindrical portion. By adjusting in this way, after the igniter 30 is activated and the gas generating agent in the sealed container 40 is combusted, the pressure in the combustion chamber 17, the gap 19 and the partition member internal space 66 of the partition member 61 increases. However, the gas generating agent 52 can be ignited smoothly and gas can be generated at a desired combustion rate by cleaving the sealing member bottom portion 43 with a predetermined breaking pressure. The sealing member bottom portion 43 is easily broken because a weak portion having a thinner film thickness than the other portion of the substantially circular bottom portion is provided in a part of the bottom portion. Note that the shape of the fragile portion is not limited to a substantially circular shape, and may be a triangular shape or a linear shape, and the shape is not particularly limited. Alternatively, a score may be provided instead. The diameter when the fragile portion is provided in a substantially circular shape is preferably smaller than the inner diameter of the cylindrical filter. When the fragile portion breaks, the remaining portion after the breakage is not filtered. Since the broken portion remains in a covering form and the broken portion is communicated, gas is prevented from being directly blown onto the filter, and the filter can be prevented from being damaged, and the inner diameter after breaking is smaller than the inner diameter of the filter. It is possible to prevent the area from being reduced and an excessive pressure loss to occur, and to function as a pressure partition. Here, even in cases other than a substantially circular shape, the same effect can be obtained if the long diameter of the fragile portion is configured to be smaller than the internal diameter of the filter.
Furthermore, it is preferable that the thermal conductivity at 0 ° C. of the substance constituting the sealed container 40 is larger than the thermal conductivity of the substance constituting the housing 10. The working gas generated from the combustion chamber 17 is ejected in the radial direction from the first opening 39 of the partition member 35, collides with the inner surface of the sealing member 41, and then moves the gap 19 in the axial direction toward the partition member. . At that time, by increasing the thermal conductivity at 0 ° C. of the material constituting the sealed container, a larger amount of heat can be absorbed in a shorter time than the conventional embodiment in which the working gas directly collides with the housing 10. As a result, the working gas is more cooled, and more particulate matter is deposited on the inner surface of the sealed container 40 and can be removed.
The airtight container 40 preferably exhibits a sufficiently large surface area of the airtight container 40 defining the gap 19 in order to exhibit a sufficient function of cooling the working gas and a function of collecting slag.
In this way, by accommodating the gas generating agent 52 and the partition member 35 in the sealed container 40, in addition to the appropriate combustion of the gas generating agent described above, more working gas cooling, removal of particulate matter, gas generation It is possible to satisfy the sealing property for preventing the entry of moisture from the outside to the agent 52 at the same time.
The cover member 42 includes a peripheral wall portion and a bottom portion extending from the peripheral wall portion, and is fitted into the inner peripheral surface of the sealed container 40 to close the end portion of the sealed container 40 on the igniter side. Here, in order to improve the sealing property, it is preferable to use a conventionally known method such as bonding the sealed container 40 and the cover part 42 by a caulking process, bonding with an adhesive, or welding.

The partition member 61 includes a cup portion 62, a flange portion 63, and a second opening 65, and is disposed in the sealed container 40 in a form that fits with the partition member. The partition member 61 can be comprised with metal members, such as stainless steel, steel, an aluminum alloy, and a stainless alloy. Moreover, as a manufacturing method of the partition member 61, any molding method of forging, cutting, and pressing may be used. Further, the opening area of the second opening 65 of the partition member 61 may be adjusted in order to make the pressure inside the combustion chamber 17 appropriate when the gas generating agent 52 burns. In the present embodiment, the partition member 61 is composed of a peripheral wall portion of the cup portion 62 and a bottom portion extending from the side wall portion, and the second opening portion 65 is provided in the peripheral wall portion, and the radial direction of the housing Communicating towards
In addition, the total area A2 of the opening areas of the plurality of second openings 65 is preferably an area formed smaller than the total area A3 of the plurality of ejection ports 11 existing on the peripheral wall of the housing.

  The gas generating agent 52 generates gas by being ignited and burned by a gas generated by burning of an igniting agent or a transfer agent ignited by the igniter 30 or by heat particles. 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. 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 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 selected as appropriate according to the specifications of the airbag apparatus in which the cylinder type gas generator is incorporated. For example, the shape in which the gas generation rate changes with time during the combustion of the gas generating agent 52 is used. It is preferable to select. 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, and the like. Moreover, as a manufacturing method of a gas generating agent, a conventionally known tableting manufacturing method, or an extrusion manufacturing method or the like may be used for a shape having a hole in the molded body.

  As the gas generating agent 52, it is particularly preferable to use a gas containing a guanidine compound as a fuel and containing a perchlorate as an oxidizing agent. If a gas generating agent containing this guanidine-based compound and perchlorate is used, there will be no toxicity problem as in the case of an azide compound.

  The coil spring 45 is disposed between the sealed container 40 and the holder 20 in a state where it is elastically compressed in the axial direction by a predetermined amount. The coil spring 45 is a member for fixing the sealed container 40, the partition member 61, and the filter 53 by urging them in the axial direction inside the housing 10. At the same time, it is a member for absorbing variations in the axial length of these components. Therefore, the coil spring 45 is sandwiched and fixed between the sealed container 40 and the holder 20 in the axial direction of the housing 10. Instead of the coil spring 45, for example, a cushion material made of a ceramic fiber molded body or foamed silicone may be used.

  The cushion material 51 corresponds to a crushing prevention member for preventing the gas generating agent 52 made of a molded body from being crushed by vibration or the like, and preferably a ceramic fiber molded body, foamed silicone, metal spring or the like is used. Is done. The cushion material 51 is opened or divided by combustion of the igniter 30 during operation, and in some cases, is burned out.

  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 a cylindrical member having a hollow portion extending in the same direction as the axial direction of the housing 10. If the filter 53 made of a cylindrical member is used in this way, when the working gas generated in the combustion chamber 17 passes through the filter 53, the gas is cooled by taking away the high-temperature heat of the gas. It functions as a cooling means and also functions as a removing means for removing slag contained in the gas. By doing so, when the slag that could not be collected when passing through the gap 19 remains, almost all of the slag can be finally collected by the filter 53. If most of the slag can be collected in the gap 19, the filter 53 may be omitted.
The filter 53 is made of, for example, a wire or net made of a metal such as stainless steel or steel, or a material that has been pressed or hardened by pressing, or a material in which a perforated metal plate is wound. . Specifically, a knitted wire mesh, a plain weave wire mesh, an assembly of crimped metal wires, or the like is used. In addition, as a perforated metal plate, for example, expanded metal that has been cut into a zigzag pattern on the metal plate and expanded to form a hole and processed into a mesh shape, or a hole is formed in the metal plate and at that time A hook metal or the like obtained by flattening the burr generated at the periphery of the hole is used. In this case, the size and shape of the hole to be formed can be appropriately changed as necessary, and holes of different sizes and shapes may be included on the same metal plate. In addition, as a metal plate, a steel plate (mild steel), a stainless steel plate, for example can be used suitably, and plates, such as aluminum, copper, titanium, nickel, or these alloys, can also be utilized.
Thus, the filter formed by winding and sintering metal wires and nets in a cylindrical shape will contain voids inside, enabling cooling of the gas described above. To do. When the working gas passes through the filter 53, the filter 53 functions as a cooling means that cools the gas by taking away the high-temperature heat of the gas, and removes residues (slag) contained in the gas. It also functions as a removing means for removing.

  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. Due to the combustion of the ignition agent, the above-described flame tears the cover member 42 and reaches the cushion material 51. The flame that has reached the cushion material 51 burns the cushion material 51 and opens or divides it, whereby the flame reaches the gas generating agent 52.

The gas generating agent 52 is ignited and burned by the flowing flame, and a large amount of gas is generated. Due to the combustion of the gas generating agent 52, the pressure in the combustion chamber 17 rises and a working gas is generated. The generated gas passes through the first opening 39 of the partition member 35 and is guided to the gap 19, and further passes through the second opening 65 of the partition member 61. The gas that has passed through cleaves the bottom 43 of the sealing member, flows into the filter chamber 18, 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 1 </ b> A. Is done. The gas ejected from the gas ejection port 11 is guided into the airbag to inflate and deploy the airbag.
Here, the generated gas passes through the first opening 39 and the gap 19 of the partition member 35 to collect and generate slag contained in the gas generated in the partition member 35, the sealed container 40 and the housing 10. The gas temperature can be lowered, and a smooth gas flow can be produced.

  As described above, by using the cylinder-type gas generator 1A in the present embodiment, the combustion residue generated from the gas generating agent is efficiently collected, so that the filter can be made small and manufactured at low cost. It can be set as the gas generator of the structure which can do.

  FIG. 4 is a schematic diagram of a gas generator according to Embodiment 2 of the present invention. Hereinafter, the configuration of the gas generator 2A in the present embodiment will be described with reference to FIGS.

As shown in FIG. 4, the gas generator 2 </ b> A according to the embodiment of the present invention is different in the configuration of the partition member 35 when compared with the gas generator 1 </ b> A according to the first embodiment of the present invention described above. . That is, in the gas generator 2A according to the second embodiment of the present invention shown in FIGS. 4 and 5, the enlarged diameter portion 36 and the deformed portion 37 are provided on the other end side of the partition member 35 different from the igniter 30 side. It is configured.
Specifically, instead of disposing the partition member 61, in the partition member 35, the first enlarged diameter portion 36 is also configured on the filter chamber 18 side. The deformable portion 37 connects the first enlarged diameter portion 36 and the main body portion 38. On the filter chamber side of the partition member 35, the deformed portion 37 is configured to gradually increase in diameter toward the filter chamber side, and is also tapered here. Moreover, the 1st enlarged diameter part 36 is in contact with the internal peripheral surface of the airtight container 40 mentioned later. The end of the partition member 35 on the filter chamber side is in contact with the inside of the sealed container 40. With such a configuration, when the partition member 35 is disposed, a gap is generated in the radial direction of the housing by the deformable portion 37, so that the gap 19 is more reliably formed between the inner peripheral surface of the sealed container 40 and the main body portion 38. Can be set.

  Next, the operation | movement at the time of the action | operation of the cylinder type gas generator 2A 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. By the combustion of the ignition powder, the above-described flame tears the cover member 42 and reaches the cushion material 51. The flame that has reached the cushion material 51 burns the cushion material 51 and opens or divides it, whereby the flame reaches the gas generating agent 52.

The gas generating agent 52 is ignited and burned by the flowing flame, and a large amount of gas is generated. Due to the combustion of the gas generating agent 52, the pressure in the combustion chamber 17 rises and a working gas is generated. Part of the generated gas passes through the first opening 39 of the partition member 35 and is guided to the gap 19, and further passes through the first opening 39 from the gap 19 and flows again into the combustion chamber 17. The inflowing gas cleaves the sealing member bottom 43 and flows into the filter chamber 18, and then is cooled to a predetermined temperature via the filter 53 and ejected from the gas ejection port 11 to the outside of the cylinder type gas generator 1 </ b> B. Is done. The gas ejected from the gas ejection port 11 is guided into the airbag to inflate and deploy the airbag.
Here, the generated gas passes through the first opening 39 and the gap 19 of the partition member 35 to collect and generate slag contained in the gas generated in the partition member 35, the sealed container 40 and the housing 10. In addition to lowering the temperature of the gas and creating a smooth flow of gas, the working gas flows into the combustion chamber 17 again, so that faster ignition of the gas generating agent can be achieved.

  Even when these configurations are employed, when the gap 19 formed between the housing 10 and the partition member 35 is formed, the same effects as those described in the present embodiment described above are obtained. Thus, a gas generator having a configuration that can be manufactured at low cost can be obtained.

Thus, the above-described embodiment disclosed herein 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.

1A to 2A Cylinder-type gas generator, 10 housing, 11 gas outlet, 17 combustion chamber, 18 filter chamber, 19 gap, 20 holder, 21 hollow opening, 23 annular groove, 26 caulking, 27 O-ring, 30 ignition 31, ignition part, 32 terminal pin, 35 partition member, 36 first enlarged diameter part, 37 deformation part, 38 main body part, 39 first opening part, 40 sealed container, 41 sealing member, 42 cover member, 43 sealing member Bottom part, 45 Coil spring, 51 Cushion material, 52 Gas generating agent, 53 Filter, 61 Partition member, 62 Cup part, 63 Flange part, 65 Second opening

Claims (1)

A long cylindrical housing in which a gas generating agent that generates gas by combustion is disposed inside and both axial ends are closed;
An igniter that is assembled to one end of the housing in the axial direction and generates a flame for burning the gas generating agent by operating;
A cylindrical partition member located inside the housing, containing the gas generating agent and forming a combustion chamber;
A gas that is located inside the housing, contains the partition member therein, and has a cylindrical sealed container that is closed at both ends containing the gas generating agent and sealed inside as a constituent element. A generator,
The thickness of the cylindrical portion in the radial direction of the housing is adjusted to be thicker than the radial thickness in the cylindrical portion of the sealed container ,
The partition member has an enlarged diameter portion such that at least one end side has substantially the same diameter as the inner diameter of the sealed container;
The diameter is adjusted to have a gap (plenum chamber) between the radially inner surface of the sealed container and the radially outer surface of the partition member, and the gas generated from the gas generating agent is inside the partition member. A main body having a gas passage hole for flowing into the plenum chamber;
Having a deformed portion located between the enlarged diameter portion and the main body portion;
The gas generator according to claim 1, wherein the enlarged diameter portion is provided at both ends of the partition member .

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