JP7280764B2 - gas generator - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas generator incorporated in an occupant protection device for protecting an occupant in the event of a vehicle collision, and more particularly to a gas generator incorporated in an airbag device installed in an automobile or the like.

2. Description of the Related Art Conventionally, from the viewpoint of protecting occupants of automobiles and the like, airbag devices, which are occupant protection devices, have been widely used. Airbag systems are installed to protect passengers from the impact that occurs in the event of a vehicle collision. By inflating and deploying the airbag instantaneously in the event of a vehicle collision, the airbag acts as a cushion for the passenger. It accepts the body.

The gas generator is incorporated in this airbag system, and when a vehicle or other vehicle collides, the igniter is ignited by the energization from the control unit, and the flame generated in the igniter burns the gas generating agent to instantly generate a large amount of gas. , the device that inflates and deploys the airbag.

Gas generators have a variety of configurations, but as a gas generator that is particularly preferably incorporated in a driver-side airbag system, a passenger-side airbag system, etc., a short, roughly circular shape with a relatively large outer diameter is used. There is a columnar disk-shaped gas generator. This disk-type gas generator also has various structures, such as a single structure having only one combustion chamber and one igniter, two combustion chambers and corresponding to these two combustion chambers. There is a dual structure with two igniters provided at the same time.

In these single-structure disk-type gas generators and dual-structure disk-type gas generators, the igniter may be arranged at a position eccentric from the central axis of the substantially cylindrical housing. Such a configuration is typically seen in many dual-type gas generators. Documents disclosing disk-type gas generators that disclose such a configuration include, for example, Japanese Patent Publication No. 2009-517263 ( There is Patent Document 1).

Japanese translation of PCT publication No. 2009-517263

Generally, in gas generators, a transfer charge is loaded between the igniter and the gas generant so that all of the gas generant will burn upon actuation. Here, in the gas generator in which the igniter is eccentrically arranged as described above, as the igniter is eccentrically arranged, it is arranged around the transfer chamber in which the transfer charge is accommodated. The amount of gas generant applied will be biased depending on the direction.

Therefore, conventionally, the transfer charge is combusted by forming the cup body defining the transfer chamber from a non-brittle member provided with a communication hole and appropriately setting the position where the communication hole is formed. Directivity is imparted to the direction in which the flame generated by this is ejected from the transfer chamber, thereby efficiently igniting the gas generating agent.

However, since the cup body made of such a non-brittle member must have high pressure resistance performance so as to withstand the pressure rise in the transfer chamber due to the combustion of the transfer charge, it is a relatively large part. If the entire cup body is made of a thick, non-brittle member, there is a problem that the parts cost will be increased. In addition, since the transfer charge is usually configured to have a fine outer shape in order to improve ignitability, the transfer charge leaks into the combustion chamber through the communication hole when the gas generator is not in operation. It is also necessary to close the communication hole with a seal tape so as to prevent it from being damaged.

Therefore, the present invention has been made in view of the above-described problems, and in a gas generator in which an igniter is arranged eccentrically, it is possible to efficiently burn a gas generating agent while reducing manufacturing costs. The purpose is to

A gas generator according to the present invention includes a housing, a filter, an igniter, a cup body, and a combustion control member. The housing includes a substantially cylindrical peripheral wall portion provided with a plurality of gas ejection ports, a top plate portion closing one axial end of the peripheral wall portion, and a bottom plate closing the other axial end of the peripheral wall portion. and has a combustion chamber inside which contains a gas generating agent. The filter comprises a substantially cylindrical member housed inside the housing so as to surround the combustion chamber. The igniter is attached to the bottom plate portion and includes an ignition portion containing an ignition charge that ignites when activated. The cup body has a top wall portion and a side wall portion defining a transfer chamber containing a transfer charge, and the transfer chamber is arranged to protrude toward the combustion chamber side so as to face the ignition portion. It is The cup body is made of a fragile member that ruptures or melts when the transfer charge burns when the igniter is activated. The combustion control member is made of a non-fragile member that does not explode or melt even when the transfer charge is burned. The combustion control member is arranged in the combustion chamber to control the spread of flame of the gas generating agent ignited by combustion of the transfer charge. The filter is arranged coaxially with the housing so that the central axis of the filter overlaps the central axis of the peripheral wall portion. The cup body is eccentrically arranged with respect to the central axis of the peripheral wall portion. The gas generating agent is arranged in a space inside the filter and adjacent to the top wall portion and the side wall portion so as to be positioned around the cup body. The combustion control member exposes at least part of a portion of the side wall portion located near the central axis of the peripheral wall portion and the top wall portion , and exposes the top wall portion of the side wall portion near the central axis of the peripheral wall portion. It has a shape that directly covers the portion located on the opposite side to the portion located on the side without intervening the gas generating agent.

The gas generator according to the present invention may further include a holder fixed to the bottom plate and holding the igniter. In that case, the combustion control member is preferably fixed to the holder.

In the gas generator according to the present invention, the holder may project from the bottom plate toward the combustion chamber. In this case, it is preferable that the combustion control member has a cylindrical fixed portion, and the fixed portion is press-fitted into the holder.

In the gas generator according to the present invention, the plurality of gas ejection ports may be spaced apart from each other along the circumferential direction of the peripheral wall portion. In that case, the opening pressure of the gas outlet located in the portion blocked by the combustion control member when viewed from the transfer chamber among the plurality of gas outlets is It is preferable that the pressure is set lower than the opening pressure of the gas ejection port located in the portion not blocked by the combustion control member when viewed from the transfer chamber.

Advantageous Effects of Invention According to the present invention, in a gas generator in which an igniter is arranged eccentrically, it is possible to reduce manufacturing costs while enabling efficient combustion of a gas generating agent.

1 is a schematic diagram of a disk-shaped gas generator according to Embodiment 1. FIG. FIG. 2 is a schematic cross-sectional view taken along line II-II shown in FIG. 1; FIG. 2 is a perspective view of the combustion control member shown in FIG. 1; FIG. 2 is an exploded perspective view showing an assembly structure of the partition shown in FIG. 1; FIG. 2 is a schematic cross-sectional view showing the first stage of operation of the disk-shaped gas generator shown in FIG. 1; FIG. 6 is a schematic cross-sectional view taken along line VI-VI shown in FIG. 5; 2 is a schematic cross-sectional view showing a second stage of operation of the disk-type gas generator shown in FIG. 1; FIG. FIG. 2 is a conceptual diagram showing a configuration example of a gas ejection port in the disk-shaped gas generator shown in FIG. 1; FIG. 10 is a perspective view of a combustion control member according to first to fifth modified examples; 4 is a schematic diagram of a disk-shaped gas generator according to Embodiment 2. FIG. FIG. 11 is a perspective view of the combustion control member shown in FIG. 10; FIG. 5 is a schematic diagram of a disk-shaped gas generator according to Embodiment 3; FIG. 13 is a conceptual diagram showing a configuration example of a gas ejection port in the disk-shaped gas generator shown in FIG. 12;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the embodiments shown below, the present invention is applied to a disk-type gas generator that is suitably incorporated in an airbag device mounted on a steering wheel or the like of an automobile. In the embodiments shown below, the same or common parts are denoted by the same reference numerals in the drawings, and the description thereof will not be repeated.

(Embodiment 1)
FIG. 1 is a schematic diagram of a disk-shaped gas generator according to Embodiment 1, and FIG. 2 is a schematic cross-sectional diagram taken along line II-II shown in FIG. 3 is a perspective view of the combustion control member shown in FIG. 1, and FIG. 4 is an exploded perspective view showing the assembly structure of the partition shown in FIG. First, the configuration of a disk-shaped gas generator 1A according to the present embodiment will be described with reference to FIGS. 1 to 4. FIG. The disk-type gas generator 1A according to this embodiment has a so-called dual structure.

As shown in FIGS. 1 and 2, the disk-shaped gas generator 1A has a short, substantially cylindrical housing with one axial end and the other end closed, and a housing provided inside the housing. In the space, a first igniter assembly 30, a second igniter assembly 40, a first gas generating agent 51, a second gas generating agent 52, a lower supporting member 61, an upper supporting member 62, and a filter are provided as internal components. 70 and the like are accommodated.

As shown in FIG. 1, the housing includes a lower shell 10 and an upper shell 20. As shown in FIG. Each of the lower shell 10 and the upper shell 20 is a press-formed product formed by pressing a rolled metal plate member, for example. As the metal plate-shaped members forming the lower shell 10 and the upper shell 20, metal plates made of stainless steel, steel, aluminum alloy, etc. are used, and preferably 440 [MPa] or more and 780 [MPa]. A so-called high-strength steel sheet that does not cause damage such as breakage even when the following tensile stress is applied is used.

The lower shell 10 and the upper shell 20 are each formed in a substantially cylindrical shape with a bottom, and a housing is constructed by combining and joining these opening surfaces facing each other. The lower shell 10 has a bottom plate portion 11 and a peripheral wall portion 12 , and the upper shell 20 has a top plate portion 21 , a peripheral wall portion 22 and a flange portion 23 .

The upper end of the peripheral wall portion 12 of the lower shell 10 is press-fitted by being inserted into the lower end of the peripheral wall portion 22 of the upper shell 20 . Further, the peripheral wall portion 12 of the lower shell 10 and the peripheral wall portion 22 of the upper shell 20 are joined at or near their abutting portions, thereby fixing the lower shell 10 and the upper shell 20. ing. Electron beam welding, laser welding, friction welding, or the like can be suitably used to join the lower shell 10 and the upper shell 20 together.

As a result, the portion of the peripheral wall portion of the housing near the bottom plate portion 11 is formed by the peripheral wall portion 12 of the lower shell 10, and the portion of the peripheral wall portion of the housing near the top plate portion 21 is formed on the upper side. It is constituted by the peripheral wall portion 22 of the shell 20 . One end and the other axial end of the housing are closed by the bottom plate portion 11 of the lower shell 10 and the top plate portion 21 of the upper shell 20, respectively.

A flange portion 23 provided on the upper shell 20 is a portion for fixing the disk-shaped gas generator 1A to an external member (for example, a retainer provided in an airbag device, etc.). A through-hole (the through-hole is not shown in the figure) is provided at a predetermined position of the flange portion 23 so as to pass through the peripheral wall portion 22 along a direction parallel to the axial direction. A fastening member such as a bolt is inserted into the through hole, thereby fixing the disk-shaped gas generator 1A to an external member.

At predetermined positions of the bottom plate portion 11 of the lower shell 10, a first opening portion 11a and a second opening portion 11b are provided. A first igniter assembly 30 is assembled to the bottom plate portion 11 of the lower shell 10 so as to close the first opening portion 11a, and a second igniter assembly 30 is assembled to close the second opening portion 11b. An assembly 40 is assembled. Here, the first opening 11a is a portion for exposing a first female connector portion (to be described later) provided at the lower end of the first igniter assembly 30 to the outside, and the second opening 11b is , a portion for exposing a second female connector portion, which will be described later, provided at the lower end of the second igniter assembly 40 to the outside.

The first igniter assembly 30 mainly includes a first holder 31, a first igniter 32, a first seal member 33, a cup body 34, a transfer charge 36, and a combustion control member 37A. The first holder 31 constitutes the base of the first igniter assembly 30. By assembling the first igniter 32, the cup body 34, the combustion control member 37A, etc. to the first holder 31, , the first igniter assembly 30 is constructed as an integral part.

The first holder 31 is made of a member having a substantially cylindrical outer shape, and is made of metal such as stainless steel, steel, or aluminum alloy. An upper concave portion 31a is provided on the upper surface of the first holder 31 positioned on the top plate portion 21 side, and a lower concave portion 31b is provided on the lower surface of the first holder 31 positioned on the bottom plate portion 11 side. there is Further, through holes 31c are provided in portions of the first holder 31 forming the bottom of the upper recess 31a and the bottom of the lower recess 31b so as to reach the upper recess 31a and the lower recess 31b.

A crimped portion 31d is provided on the upper surface of the first holder 31 so as to surround the upper concave portion 31a. The crimped portion 31 d is a portion for crimping and fixing the first igniter 32 to the first holder 31 .

The first igniter 32 is for generating flame, and has a base portion 32a, an ignition portion 32b, and a pair of terminal pins 32c. The base portion 32 a is a portion that holds the ignition portion 32 b and the pair of terminal pins 32 c and is also a portion that is fixed to the first holder 31 . The ignition part 32b contains therein an ignition charge that generates a flame by being ignited and burned during operation, and a resistor (bridge wire) for igniting the ignition charge. A pair of terminal pins 32c are connected to the ignition portion 32b to ignite the ignition charge.

More specifically, the ignition part 32b includes a cup-shaped squib cup, and an embolus that closes the open end of the squib cup and holds a pair of terminal pins 32c inserted therethrough. The above-mentioned resistor is attached so as to connect the tips of a pair of terminal pins 32c inserted into the squib cup, and an ignition charge is placed in the squib cup so as to surround or be close to the resistor. It has a loaded configuration.

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 igniter. Note that the squib cups and emboli described above are generally made of metal or plastic.

When a collision is detected, a predetermined amount of current flows through the resistor through the terminal pin 32c. When a predetermined amount of current flows through the resistor, Joule heat is generated in the resistor, and the ignition charge starts burning. The high temperature flame produced by the combustion ruptures the squib cup containing the ignition charge. The time from when the current flows through the resistor until the first igniter 32 is activated is generally 2 [ms] or less when the nichrome wire is used for the resistor.

In the first igniter 32, the pair of terminal pins 32c are inserted into the through holes 31c of the first holder 31 from above, and the base portion 32a is accommodated in the upper recessed portion 31a of the first holder 31 and fixed. It is fixed to the first holder 31 by bending the crimped portion 31d described above.

Here, a first seal member 33 made of an O-ring or the like is interposed between the first holder 31 and the first igniter 32 , and thereby a seal between the first holder 31 and the first igniter 32 is provided. By closing the gap between them, the airtightness of the part is ensured. In addition, the fixing method of the 1st igniter 32 is not restricted to the fixing method using the crimping|crimped part 31d mentioned above, You may utilize another fixing method.

The cup body 34 has a cup-like shape with an open end on the bottom plate portion 11 side, and includes a transfer chamber 35 in which a transfer charge 36 is accommodated. The cup body 34 has a top wall portion 34a and a side wall portion 34b that define the transfer chamber 35, and a flange portion 34c that extends radially outward from the opening end side portion of the side wall portion 34b. there is

The cup body 34 is assembled to the first holder 31 so that a transfer chamber 35 formed therein faces the ignition portion 32b of the first igniter 32. More specifically, the flange portion 34c is In the state of being abutted against the upper surface of the first holder 31, the flange portion 34c is pressed against the first holder 31 by a pressing portion 37d of the combustion control member 37A, which will be described later, thereby being fixed to the first holder 31. there is

The cup body 34 has an opening in neither the top wall portion 34a nor the side wall portion 34b, and surrounds a transfer chamber 35 provided therein. The cup body 34 is made of a fragile member that bursts or melts as the pressure rises in the transfer chamber 35 or the conduction of the generated heat when the transfer charge 36 is ignited by the operation of the first igniter 32. Become.

Therefore, as the cup body 34, metal members such as aluminum and aluminum alloys, thermosetting resins such as epoxy resins, polybutylene terephthalate resins, polyethylene terephthalate resins, polyamide resins (for example, nylon 6 and nylon 66 etc.), a member made of a thermoplastic resin such as a polypropylene sulfide resin, a polypropylene oxide resin, or the like is preferably used.

The transfer charge 36 filled in the transfer chamber 35 is ignited by the flame generated by the operation of the first igniter 32, and burns to generate thermal particles. The transfer charge 36 must be capable of reliably starting combustion of the first gas generating agent 51, and is generally B/KNO ₃ , B/NaNO ₃ , Sr(NO ₃ ). _2, etc., a composition consisting of metal powder/oxidizing agent, a composition consisting of titanium hydride/potassium perchlorate, a composition consisting of B/5-aminotetrazole/potassium nitrate/molybdenum trioxide, etc. are used. .

As the transfer charge 36, a powdery one, a binder molded into a predetermined shape, or the like is used. The shape of transfer charge 36 formed by the binder includes various shapes such as granular, cylindrical, sheet, spherical, single-hole cylindrical, multi-hole cylindrical, and tablet-like.

As shown in FIGS. 1 to 3, the combustion control member 37A has a substantially cylindrical shape, and has a barrier portion 37a, an open portion 37b, a fixed portion 37c, and a pressing portion 37d. ing. The combustion control member 37A is made of a non-brittle member that does not explode or melt when the transfer charge 36 burns, and is made of metal such as stainless steel or steel. In addition, the combustion control member 37A may be made of a heat-resistant resin having a melting point exceeding 300[° C.]. Examples of the heat-resistant resin include polyimide resin and polyamide resin.

The combustion control member 37A is arranged so that its axial direction is parallel to the axial direction of the housing. It functions as a fixed portion 37c. More specifically, the fixed portion 37c has a substantially cylindrical shape, and the portion to be fixed 37c protrudes from the bottom plate portion 11 toward the first combustion chamber SA1, which will be described later. By being press-fitted into the first holder 31 , the combustion control member 37A is assembled to the bottom plate portion 11 via the first holder 31 .

The combustion control member 37A is for controlling the spread of the flame of the first gas generating agent 51, which is ignited by the combustion of the transfer charge 36, and more specifically, the flame generated by the combustion of the transfer charge 36 is controlled. Directivity is provided so that the fuel is ejected from the transfer chamber 35 in a predetermined direction. The function of imparting directivity to the flame generated by burning the transfer charge 36 is mainly exhibited by the barrier portion 37a and the open portion 37b provided in the combustion control member 37A.

That is, the barrier portion 37a is formed by the side wall portion 34b of the portion of the top wall portion 34a and the side wall portion 34b of the cup body 34 that defines the transfer chamber 35, which is located on the opposite side of the portion located near the central axis of the housing. The opening portion 37b is positioned so as to expose the top wall portion 34a and the side wall portion 34b of the portion near the central axis of the housing. Here, in FIG. 3, arrow A indicates the direction in which the central axis of the housing is located when viewed from the combustion control member 37A. In the combustion control member 37A according to the present embodiment, the opening angle of the open portion 37b in the circumferential direction of the combustion control member 37A is set to approximately 120°, and the upper end thereof reaches the upper end opening of the combustion control member 37A. It is configured as follows.

As a result, when the transfer charge 36 burns, the portion of the top wall portion 34a and the side wall portion 34b of the cup body 34 exposed by the open portion 37b bursts or melts due to the combustion of the transfer charge 36. As a result, the flame generated by the combustion of the transfer charge 36 is spouted into the first combustion chamber SA1 in a predetermined direction.

The holding portion 37d is formed by bending the combustion control member 37A between the barrier portion 37a and the fixed portion 37c. The cup body 34 is fixed to the first holder 31 as described above by being pressed against the upper surface.

As shown in FIG. 1, the lower end of the first holder 31 is inserted from above into the first opening 11a provided in the bottom plate portion 11 of the lower shell 10, and the outer peripheral edge thereof It is fixed by joining. As a result, the first igniter assembly 30, which is integrated by previously assembling the first igniter 32, the cup body 34, the combustion control member 37A, and the like to the first holder 31, is attached to the lower shell 10. will be fixed.

Therefore, the first holder 31 is configured to protrude from the bottom plate portion 11 toward the space inside the housing. 35 will be located in the space inside the housing. Electron beam welding, laser welding, friction welding, or the like can be suitably used to join the bottom plate portion 11 and the first holder 31 together.

A pair of terminal pins 32c of the first igniter 32 are exposed and located in the lower recessed portion 31b of the first holder 31 . As a result, the lower concave portion 31b and the pair of terminal pins 32c form the above-described first female connector portion.

The first female connector portion is a portion for receiving a male connector (not shown) of a harness for connecting the first igniter 32 and a control unit (not shown). The first female connector portion is exposed to the outside of the housing, and the male connector described above is inserted into the first female connector portion to electrically connect the core wire of the harness and the terminal pin 32c. Conduction will be realized.

As shown in FIG. 1, the second igniter assembly 40 mainly includes a second holder 41, a second igniter 42, a second seal member 43, a partition portion 44, and a second gas generating agent 52. contains. The second holder 41 constitutes the base of the second igniter assembly 40. By assembling the second igniter 42 and the partition part 44 and the like to the second holder 41, the second igniter Assembly 40 is constructed as an integral part.

The second holder 41 is made of a member having a substantially cylindrical outer shape, and is made of metal such as stainless steel, iron steel, aluminum alloy, or the like. An upper concave portion 41a is provided on the upper surface of the second holder 41 positioned on the top plate portion 21 side, and a lower concave portion 41b is provided on the lower surface of the second holder 41 positioned on the bottom plate portion 11 side. there is Further, through holes 41c are provided in the second holder 41 in portions forming the bottom of the upper recess 41a and the bottom of the lower recess 41b so as to reach the upper recess 41a and the lower recess 41b.

A crimped portion 41d is provided on the upper surface of the second holder 41 so as to surround the upper concave portion 41a. The crimped portion 41 d is a portion for crimping and fixing the second igniter 42 to the second holder 41 .

The second igniter 42 is for generating flame, and has a base portion 42a, an ignition portion 42b, and a pair of terminal pins 42c. The base portion 42 a is a portion that holds the ignition portion 42 b and the pair of terminal pins 42 c and is also a portion that is fixed to the second holder 41 . Since the second igniter 42 basically has the same configuration as the first igniter 32 described above, detailed description thereof will be omitted here.

In the second igniter 42, the pair of terminal pins 42c are inserted into the through holes 41c of the second holder 41 from above, and the base portion 42a is housed in the upper concave portion 41a of the second holder 41 and fixed. It is fixed to the second holder 41 by bending the caulked portion 41d described above.

Here, a second seal member 43 made of an O-ring or the like is interposed between the second holder 41 and the second igniter 42 , thereby separating the second holder 41 and the second igniter 42 . By closing the gap between them, the airtightness of the part is ensured. In addition, the fixing method of the 2nd igniter 42 is not restricted to the fixing method using the crimping|crimped part 41d mentioned above, You may utilize another fixing method.

The partition part 44 has a partition member 45, a cover member 46, and a cap member 47. The partition member 45, the cover member 46, and the cap member 47 are combined to form a cup-like shape as a whole. are doing. The partition part 44 functions as a pressure partition wall that partitions the combustion chamber, which is the space inside the housing and inside the filter 70, into two chambers.

As shown in FIGS. 1 and 2, the combustion chamber, which is the space inside the housing and the space inside the filter 70, is divided by the partition 44 into the space outside the partition 44 and the space outside the partition 44. The former space is defined as the first combustion chamber SA1, and the latter space is defined as the second combustion chamber SA2.

As shown in FIG. 1, the partition part 44 is assembled to the second holder 41 so that the second combustion chamber SA2 formed therein faces the ignition part 42b of the second igniter 42. As shown in FIG. More specifically, as will be described later, the fixed portion 45 a provided at the lower end of the partition member 45 of the partition portion 44 is press-fitted into the second holder 41 , thereby causing the partition portion 44 to move the second holder 41 . It is fixed to the bottom plate portion 11 via the bottom plate portion 11 .

A second gas generating agent 52 is accommodated in the second combustion chamber SA2 positioned inside the partition portion 44 . The second gas generating agent 52 is a chemical that is ignited by hot particles generated by the operation of the second igniter 42 and burns to generate gas. Details of the second gas generating agent 52 will be described later.

As shown in FIGS. 1, 2 and 4, the partition member 45 has a tubular shape with openings at both ends in the axial direction. The partition member 45 is arranged so that its axial direction is parallel to the axial direction of the housing. It functions as the fixed portion 45a.

More specifically, the portion to be fixed 45a is press-fitted into the second holder 41 as described above. 44 is attached to the bottom plate portion 11 . In addition, the partition member 45 is made of a metal member such as stainless steel, steel, or aluminum alloy.

The cover member 46 has a cup-like shape with an open end on the bottom plate portion 11 side, and is attached to the open end of the partition member 45 on the top plate portion 21 side. Like the partition member 45, the cover member 46 is made of a metal member such as stainless steel, steel, or aluminum alloy.

The cover member 46 includes a disk-shaped first cover portion 46a that constitutes the closed end of the partition portion 44 by covering the opening of the partition member 45 located on the top plate portion 21 side, and the peripheral edge of the first cover portion 46a. It includes a cylindrical second cover portion 46 b that extends toward the bottom plate portion 11 side to cover the outer peripheral surface of the portion of the partition member 45 near the top plate portion 21 .

The cover member 46 is attached to the partition member 45 by being fitted over the above-described open end of the partition member 45, and preferably fixed to the partition member 45 by press fitting. Thereby, the second cover portion 46b of the cover member 46 is in close contact with the outer peripheral surface of the partition member 45 described above.

The cap member 47 has a cup-like shape with an open end on the bottom plate portion 11 side, and is inserted into a portion of the partition member 45 near the top plate portion 21 . Thereby, the cap member 47 is housed in a space defined by the partition member 45 and the cover member 46 (that is, corresponding to the second combustion chamber SA2). Like the partition member 45 , the cap member 47 is made of a metal member such as stainless steel, iron steel, or aluminum alloy, but is sufficiently thinner than the partition member 45 .

The cap member 47 includes a disk-shaped top plate portion 47a disposed between the second gas generating agent 52 and the first cover portion 46a of the cover member 46, and a top plate portion 47a extending from the peripheral edge of the top plate portion 47a toward the bottom plate portion 11 side. and an extended cylindrical peripheral plate portion 47b.

The cap member 47 is accommodated in the partition member 45 by being inserted into the above-described open end of the partition member 45 , and more specifically, is press-fitted or loosely fitted to the partition member 45 . Here, the loose fitting means that the cap member 47 fitted in the partition member 45 has a predetermined clearance with the partition member 45. The cap member 47 is attached to the partition member 45 by fitting.

A peripheral plate portion 47b of the cap member 47 is provided with a plurality of gas passage holes 47c arranged in a dotted line along the circumferential direction. The plurality of gas passage holes 47c are for passing the gas generated in the second combustion chamber SA2 toward the space outside the partition portion 44 when the second gas generating agent 52 is burned. It is provided so as to penetrate the peripheral plate portion 47b along the thickness direction of the plate portion 47b.

As shown in FIG. 1, the lower end of the second holder 41 is inserted from above into the second opening 11b provided in the bottom plate portion 11 of the lower shell 10, and the outer peripheral edge thereof It is fixed by joining. As a result, the second igniter assembly 40, which is integrated by previously assembling the second igniter 42 and the partition portion 44 to the second holder 41, is fixed to the lower shell 10. become.

Therefore, the second holder 41 is configured to protrude from the bottom plate portion 11 toward the space inside the housing. A chamber SA2 will be arranged in the space inside the housing. Electron beam welding, laser welding, friction welding, or the like can be suitably used to join the bottom plate portion 11 and the second holder 41 together.

A pair of terminal pins 42c of the second igniter 42 are exposed and located in the lower concave portion 41b of the second holder 41 . As a result, the lower recessed portion 41b and the pair of terminal pins 42c form the second female connector portion described above.

The second female connector portion is a portion for receiving a male connector (not shown) of a harness for connecting the second igniter 42 and a control unit (not shown). The second female connector portion is exposed to the outside of the housing, and the above-described male connector is inserted into the second female connector portion to electrically connect the core wire of the harness and the terminal pin 42c. Conduction will be realized.

As shown in FIGS. 1 and 2, the space inside the housing accommodates a filter 70 in addition to the first igniter assembly 30 and the second igniter assembly 40 described above. The filter 70 has a cylindrical shape and is arranged coaxially with the housing such that its central axis coincides with the central axis of the peripheral wall portion of the housing. As a result, the outer peripheral surface of the filter 70 faces the inner peripheral surface of the peripheral wall portion of the housing.

The filter 70 surrounds the first igniter assembly 30 and the second igniter assembly 40 so that the first igniter assembly 30 and the second igniter assembly 40 are arranged in the inner space. are placed in As a result, the first combustion chamber SA1 in which the first gas generating agent 51 is accommodated is formed in the space inside the filter 70 and outside the partition portion 44 . The filter 70 is arranged at a predetermined distance from the peripheral wall portion of the housing, thereby forming a gas discharge chamber SB between the peripheral wall portion of the housing and the filter 70 .

As the filter 70, for example, a metal wire rod such as stainless steel or iron steel wound and sintered, or a mesh material woven with a metal wire rod pressed by pressing can be used. As the mesh material, specifically, a knitted wire mesh, a plain-woven wire mesh, an aggregate of crimp-woven metal wires, or the like can be used.

As the filter 70, a wound perforated metal plate or the like can also be used. In this case, the perforated metal plate may be, for example, an expanded metal obtained by cutting a metal plate in a zigzag pattern and expanding the cuts to form holes to form a mesh, or a metal plate with holes and A hook metal or the like is used in which burrs formed on the periphery of the hole are flattened by crushing them. In this case, the size and shape of the holes to be formed can be changed as needed, and holes of different sizes and shapes may be included on the same metal plate. As the metal plate, for example, a steel plate (mild steel) or a stainless steel plate can be suitably used, and a non-ferrous metal plate such as aluminum, copper, titanium, nickel or alloys thereof can also be used.

The filter 70 functions as a cooling means for cooling the gas by removing high-temperature heat from the gas generated in the first combustion chamber SA1 and the second combustion chamber SA2 as it passes through the filter 70. At the same time, it also functions as a removing means for removing residues (slag) and the like contained in the gas.

Here, the first igniter assembly 30 is eccentrically arranged so that its central axis does not overlap the central axis of the peripheral wall of the housing, and the second igniter assembly 40 also has its central axis aligned with the peripheral wall of the housing. It is eccentrically arranged so as not to overlap with the central axis of the part. By constructing in this way, it is possible to prevent the occurrence of dead space inside the housing, and to construct the disc-type gas generator 1A as a whole in a small size.

A first gas generating agent 51 is accommodated in the first combustion chamber SA1. The first gas generating agent 51 is an agent that is ignited by hot particles generated by the operation of the first igniter 32 and burns to generate gas. ing.

More specifically, the first gas generating agent 51 is contained in the space inside the filter 70 and adjacent to the top wall portion 34a and the side wall portion 34b of the cup body 34 of the first igniter assembly 30, and , the space inside the filter 70 and adjacent to the side wall of the partition portion 44 of the second igniter assembly 40 .

However, as described above, since the combustion control member 37A of the first igniter assembly 30 is arranged in the first combustion chamber SA1, in the portion where the barrier portion 37a of the combustion control member 37A is located, The side wall portion 34b of the cup body 34 does not directly face the first gas generating agent 51, and the barrier portion 37a is interposed therebetween.

As the first gas generating agent 51 and the second gas generating agent 52 described above, it is preferable to use a non-azide gas generating agent. 51 and a second gas generant 52 are formed.

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, nitroguanidine, guanidine nitrate, cyanoguanidine, 5-aminotetrazole and the like are preferably used.

Examples of the oxidizing agent include basic nitrates such as basic copper nitrate, basic carbonates such as basic copper carbonate, perchlorates such as ammonium perchlorate and potassium perchlorate, alkali metals and alkaline earth metals. , transition metals, and nitrates containing cations selected from ammonia are used. As nitrates, for example, sodium nitrate, potassium nitrate and the like are preferably used.

Additives include binders, slag forming agents, and combustion modifiers. As the binder, for example, organic binders such as polyvinyl alcohol, metal salts of carboxymethyl cellulose and stearates, and inorganic binders such as synthetic hydrotalcite and acid clay can be preferably used. In addition, binders include polysaccharide derivatives such as hydroxyethyl cellulose, hydroxypropyl methyl cellulose, cellulose acetate, cellulose propionate, cellulose acetate butyrate, nitrocellulose, microcrystalline cellulose, guar gum, polyvinylpyrrolidone, polyacrylamide, and starch. Alternatively, inorganic binders such as molybdenum disulfide, talc, bentonite, diatomaceous earth, kaolin, and alumina can be suitably used. As the slag forming agent, silicon nitride, silica, acid clay, etc. can be suitably used. Metal oxides, ferrosilicon, activated carbon, graphite and the like can be suitably used as combustion modifiers.

The shape of the molded body of the gas generating agent includes various shapes such as granules, pellets, granules such as cylinders, and discs. In addition, in the case of a columnar shape, a perforated shaped body having through holes inside the shaped body (for example, a single-hole cylindrical shape, a porous cylindrical shape, etc.) is also used. These shapes are preferably selected appropriately according to the specifications of the airbag device in which the disk-type gas generator 1A is incorporated. It is preferable to select the optimum shape according to the specifications. In addition to the shape of the gas generating agent, it is preferable to appropriately select the size and filling amount of the molded body in consideration of the linear burning velocity, pressure index, etc. of the gas generating agent.

Here, the first gas generating agent 51 and the second gas generating agent 52 may have the same composition or may have different compositions. The first gas generating agent 51 and the second gas generating agent 52 may have the same shape and size, or may have different shapes and sizes.

The peripheral wall portion 22 of the upper shell 20 facing the filter 70 is provided with a plurality of gas ejection ports 24 facing the gas discharge chamber SB. More specifically, the plurality of gas ejection ports 24 are provided in a dotted line at intervals along the circumferential direction of the peripheral wall portion 22 of the upper shell 20 so as to surround the space inside the housing. located in These gas ejection ports 24 are for discharging the gas that has passed through the filter 70 to the outside of the housing via the gas discharge chamber SB.

A metal sealing tape 25 is attached as a sealing member to the inner peripheral surface of the peripheral wall portion 22 of the upper shell 20 so as to close the plurality of gas ejection ports 24 . As the seal tape 25, an aluminum foil or the like coated with an adhesive member on one side can be suitably used, and the seal tape 25 ensures the airtightness of the space inside the housing.

As shown in FIG. 1, a lower support member 61 is arranged at an end portion of the first combustion chamber SA1 located on the bottom plate portion 11 side. The lower support member 61 has an annular shape, and is placed between the filter 70 and the bottom plate portion 11 so as to cover the boundary portion between the filter 70 and the bottom plate portion 11 . Thereby, the lower support member 61 is positioned between the bottom plate portion 11 and the first gas generating agent 51 in the vicinity of the end portion of the first combustion chamber SA1.

The lower support member 61 is a member for fixing the filter 70 to the housing, and also allows gas generated in the first combustion chamber SA1 and the second combustion chamber SA2 to pass through the inside of the filter 70 during operation. It also functions as an outflow prevention means for preventing the water from flowing out from the gap between the lower end of the filter 70 and the bottom plate portion 11 . The lower support member 61 is formed, for example, by pressing a metal plate member, and is preferably made of a steel plate such as ordinary steel or special steel (for example, cold-rolled steel plate, stainless steel plate, etc.). It is composed of the following members.

An upper support member 62 is arranged at an end portion of the first combustion chamber SA1 that is located on the top plate portion 21 side. The upper support member 62 has a substantially disk-like shape, and is placed between the filter 70 and the top plate portion 21 so as to cover the boundary portion between the filter 70 and the top plate portion 21 . Thereby, the upper support member 62 is positioned between the top plate portion 21 and the first gas generating agent 51 in the vicinity of the end portion of the first combustion chamber SA1.

The upper support member 62 is a member for fixing the filter 70 to the housing, and prevents gas generated in the first combustion chamber SA1 and the second combustion chamber SA2 from passing through the inside of the filter 70 during operation. It also functions as an outflow preventing means for preventing outflow from the gap between the upper end of the filter 70 and the top plate portion 21 . Like the lower support member 61 described above, the upper support member 62 is formed by, for example, pressing a plate-like member made of metal, and is preferably made of a steel plate such as ordinary steel or special steel (for example, cold-rolled steel plate, stainless steel plate, etc.).

Inside the upper support member 62, a substantially C-shaped cushion member 63 in plan view is arranged so as to come into contact with the first gas generating agent 51 accommodated in the first combustion chamber SA1. As a result, the cushion material 63 is positioned between the top plate portion 21 and the first gas generating agent 51 in the portion of the first combustion chamber SA1 on the side of the top plate portion 21, thereby removing the first gas generating agent 51. It is pressed toward the bottom plate portion 11 side.

The cushion material 63 is provided for the purpose of preventing the first gas generating agent 51 made of a molded body from being pulverized by vibration or the like. For example, foamed silicone, foamed polypropylene, foamed polyethylene, foamed urethane, etc.), chloroprene, EPDM, and other rubbers. Note that the cushion material 63 is burnt out by combustion of the first gas generating agent 51 .

If it is necessary to prevent the second gas generating agent 52 from being crushed by vibration, it can be realized by using a cushioning material, as in the case of the first gas generating agent 51 . In that case, a disk-shaped cushioning material is arranged between the closed end of the partition part 44 located on the top plate part 21 side and the second gas generating agent 52, or an annular disk-shaped cushioning material is provided. It can be arranged either between the upper surface of the second holder 41 surrounding the second igniter 42 and the second gas generating agent 52 .

When the former configuration is adopted, the second gas generating agent 52 is pressed toward the bottom plate portion 11 by the cushioning material. The generating agent 52 is pressed toward the top plate portion 21 side. Both the former configuration and the latter configuration may be adopted. Here, as the cushion material for pressing the second gas generating agent 52 described above, the same material as the cushion material 63 for pressing the first gas generating agent 51 can be used.

FIG. 5 is a schematic cross-sectional view showing the first stage of operation of the disk-type gas generator according to the present embodiment, and FIG. 6 is a schematic cross-sectional view along line VI-VI shown in FIG. be. FIG. 7 is a schematic cross-sectional view showing the second stage of operation of the disk-type gas generator according to this embodiment. Next, operation of the disk-shaped gas generator 1A according to the present embodiment will be described with reference to FIGS. 5 to 7. FIG.

When the vehicle equipped with the disk-type gas generator 1A collides, the collision is detected by collision detection means separately provided in the vehicle, and based on this, power is received from a control unit separately provided in the vehicle. , the first igniter 32 is activated first.

As shown in FIGS. 5 and 6, in the first stage in which the first igniter 32 operates, the ignition charge filled in the ignition portion 32b of the first igniter 32 is ignited by being heated by the resistor. , the ignition portion 32b bursts due to the combustion of the ignition charge. As a result, the transfer charge 36 housed inside the cup body 34 is ignited and burned.

When the transfer charge 36 burns, a large amount of heat particles are generated inside the transfer chamber 35, and the temperature and pressure of the transfer chamber 35 rise, causing the cup body 34 made of a fragile member to burst or melt. . As the cup body 34 ruptures or melts, the transfer chamber 35 communicates with the first combustion chamber SA1, and the large amount of heat particles described above flow into the first combustion chamber SA1.

At this time, of the top wall portion 34a and the side wall portion 34b of the cup body 34, part of the side wall portion 34b is covered with the barrier portion 37a of the combustion control member 37A. (that is, the portion exposed toward the first combustion chamber SA1 by the open portion 37b of the combustion control member 37A of the cup body 34) bursts or melts and is covered with the barrier portion 37a The part remains without bursting or melting.

As a result, the flame generated by the combustion of the transfer charge 36 blows out toward the top plate portion 21 side of the upper shell 20 and the central axis side of the housing, as indicated by an arrow AR1 in the drawing. , is prevented from blowing out to the side where the barrier portion 37a is located when viewed from the transfer chamber 35. Therefore, among the first gas generating agents 51 positioned around the first igniter assembly 30, the first gas generating agents 51 positioned in directions other than the direction in which the barrier portion 37a is positioned when viewed from the transfer chamber 35 are It is ignited and starts burning.

Of the first gas generating agents 51 positioned around the first igniter assembly 30, the first gas generating agent 51 positioned on the barrier portion 37a side when viewed from the transfer chamber 35 starts burning first. Combustion is started at a delayed timing along with the spread of the flame of the first gas generating agent 51 .

As the first gas generating agent 51 burns, a large amount of gas is generated in the first combustion chamber SA1. The gas generated in the first combustion chamber SA1 passes through the inside of the filter 70. At this time, the filter 70 removes heat and cools the gas. It flows into the discharge chamber SB.

At this time, the seal tape 25 closing the plurality of gas ejection ports 24 is torn due to an increase in pressure inside the housing caused by combustion of the first gas generating agent 51 . As a result, the gas generated in the first combustion chamber SA1 starts to be ejected toward the outside of the housing through the plurality of gas ejection ports 24 (see arrow AR2).

On the other hand, in the first stage, the cover member 46 is pressed against the partition member 45 due to the pressure increase in the first combustion chamber SA1 caused by the combustion of the first gas generating agent 51. . Therefore, the opening of the partition member 45 on the top plate portion 21 side is closed by the first cover portion 46 a of the cover member 46 , and the outer peripheral surface of the portion of the partition member 45 near the top plate portion 21 is covered with the first cover member 46 . Since the second cover portion 46b is in close contact, the state in which the portion is covered is maintained.

As a result, in the first stage, the first combustion chamber SA1 and the second combustion chamber SA2 are not communicated with each other, and the second gas generating agent 52, which has not yet started to burn, is supplied with the first gas generating agent. 51 will no longer be affected.

Next, the second igniter 42 is energized by the above-described control unit at a timing delayed by a predetermined time from the operation of the first igniter 32 described above.

As shown in FIG. 7, in the second stage in which the second igniter 42 operates, the ignition charge filled in the ignition portion 42b of the second igniter 42 is heated by the resistor and ignited. The ignition part 42b bursts due to the combustion of the gunpowder. As a result, the second gas generating agents 52 housed in the second combustion chamber SA2 are sequentially ignited and start burning.

Here, prior to the start of combustion of the second gas generating agent 52, the first gas generating agent 51 was previously ignited and burned, so that the disk-type gas generator 1A as a whole was already heated to a high temperature. Therefore, even if no transfer charge is provided between the ignition part 42b and the second gas generating agent 52, the combustion of the second gas generating agent 52 is started smoothly, and the second gas is generated. Combustion of the agent 52 is less likely to be interrupted.

At this time, pressure is applied to the cap member 47 accommodated in the second combustion chamber SA2 due to the pressure increase in the second combustion chamber SA2 caused by the combustion of the second gas generating agent 52. The pressure acts on the top plate portion 47a of the cap member 47 mainly in the direction along the axial direction of the housing, and the pressure acts on the peripheral plate portion 47b of the cap member 47 in the direction mainly along the radial direction of the housing. The pressure acts on

As a result, the entire cap member 47 moves toward the top plate portion 21 of the upper shell 20, and the peripheral plate portion 47b deforms so as to expand radially outward. Become. Therefore, the cap member 47 moves toward the top plate portion 21 while the portion of the peripheral plate portion 47b near the lower end is kept in close contact with the inner peripheral surface of the partition member 45 along the circumferential direction. As a result, the internal pressure of the second combustion chamber SA2 rises appropriately, and the combustion of the second gas generating agent 52 continues without interruption.

As the cap member 47 moves as described above, the cover member 46 is pushed up by the cap member 47 and moves toward the top plate portion 21 side. As a result, the cap member 47 is separated from the open end of the partition member 45 on the top plate portion 21 side. Therefore, when the cover member 46 is separated from the partition member 45, the gas passage hole 47c provided in the peripheral plate portion 47b of the cap member 47 is located at the position on the top plate portion 21 side of the partition member 45 and is located in the first combustion chamber SA1. exposed to face

Here, in the present embodiment, when the movement of the cover member 46 and the cap member 47 in the second stage occurs by a predetermined amount, the movement of the cover member 46 and the cap member 47 is caused by the top plate portion 21. configured to be restricted. That is, the cover member 46 contacts the top plate portion 21 via the upper support member 62, and the cap member 47 contacts the top plate portion 21 via the cover member 46 and the upper support member 62, thereby The cover member 46 and the cap member 47 will stop.

As a result, as indicated by an arrow AR3 in the drawing, the gas generated in the second combustion chamber SA2 passes through the plurality of gas passage holes 47c provided in the peripheral plate portion 47b, thereby passing through the first combustion chamber SA1. will be introduced into

The gas generated in the second combustion chamber SA2 and then introduced into the first combustion chamber SA1 passes through the inside of the filter 70. At this time, the filter 70 removes heat and cools the gas. The contained slag is removed by the filter 70 and flows into the gas discharge chamber SB, and is then jetted out of the housing through the plurality of gas jet ports 24 (see arrow AR2).

In the above-described first and second stages, the gas ejected from the plurality of gas ejection ports 24 to the outside of the disk-shaped gas generator 1A is injected into the air space provided adjacent to the disk-shaped gas generator 1A. It is introduced inside the bag to inflate and deploy the airbag.

As described above, in the disk-type gas generator 1A according to the present embodiment, the transfer charge 36 is displaced due to the combustion control member 37A having a predetermined shape being arranged inside the first combustion chamber SA1. The flame generated by burning is directed toward the central axis of the housing.

Therefore, in the initial stage of operation of the disk-type gas generator 1A, the central axis side portion of the housing, where the amount of the first gas generating agent 51 disposed around it is larger when viewed from the transfer chamber 35, The first gas generating agent 51 is ignited. Therefore, by configuring in this way, it becomes possible to burn the first gas generating agent 51 efficiently.

On the other hand, in the disk-shaped gas generator 1A according to the present embodiment, the cup body 34 is not made of a non-brittle member having high pressure resistance, but is made of a very cheap and fragile member. Since it is configured, the parts cost can be greatly reduced.

Here, in the present embodiment, a combustion control member 37A made of a non-brittle member is required in addition to the cup body 34 in order to give directivity to the direction in which the flame generated by the combustion of the transfer charge 36 blows out. However, the thickness of the combustion control member 37A can be made sufficiently thin compared to the case where the cup body 34 is formed of a non-brittle member, and the amount of material used is sufficient. Since the number of components is small, the component cost is naturally low, and even if the component cost of the cup body 34 made of the above-described non-fragile member is added, the total cost is sufficiently low.

The reason why the thickness of the combustion control member 37A can be made sufficiently thin is that if the cup body 34 is made of a non-brittle member, extremely high pressure resistance is required to maintain the internal pressure. This is because the combustion control member 37A is not required to have such performance.

Therefore, by using the disk-shaped gas generator 1A according to the present embodiment, it is possible to efficiently burn the first gas generating agent 51 even in a configuration in which the first igniter 32 is arranged eccentrically. In addition, it becomes possible to reduce the manufacturing cost.

Further, in the disk-type gas generator 1A according to the present embodiment, the combustion control member 37A is provided with a substantially cylindrical fixed portion 37c, and the fixed portion 37c is press-fitted into the first holder 31, whereby combustion is The control member 37A is fixed to the bottom plate portion 11 of the housing via the first holder 31. As shown in FIG. With this configuration, the combustion control member 37A can be installed inside the first combustion chamber SA1 very easily, and the assembly work is facilitated, thereby reducing the manufacturing cost. It will also be

In addition, in the disk-shaped gas generator 1A according to the present embodiment, the portion of the side wall portion 34b of the cup body 34 located on the opposite side to the portion located near the central axis of the housing is filled with the first gas. Since the structure is such that it is directly covered by the barrier portion 37a of the combustion control member 37A without intervening the generating agent 51, the first gas generating agent 51 in the portion located in the immediate vicinity of the filter 70 starts burning early. will disappear. Therefore, there is a secondary effect that it is possible to prevent the occurrence of the problem that the first gas generating agent 51 located in the immediate vicinity of the filter 70 starts burning early and the filter 70 is induced to break. You can also get

FIGS. 8A and 8B are conceptual diagrams showing configuration examples of the gas ejection port in the disk-type gas generator according to the present embodiment, and FIGS. 1 shows a disk-shaped gas generator according to an example configuration. Hereinafter, a disk-shaped gas generator 1A' according to the first structural example and a disk-shaped gas generator 1A'' according to the second structural example will be described with reference to FIG.

In general, the output characteristics of a gas generator are affected by the surrounding environment in which the gas generator is placed, particularly depending on the ambient temperature, with the output characteristics becoming stronger in a high-temperature environment and weaker in a low-temperature environment. There is a tendency. That is, in a high-temperature environment, the combustion of the gas generating agent is promoted, so that the internal pressure of the combustion chamber rises quickly, and the gas is ejected more quickly and strongly, and in a low-temperature environment, the gas generating agent Suppression of combustion slows down the increase in internal pressure in the combustion chamber, resulting in a slower and weaker jet of gas.

Therefore, especially in a low-temperature environment, there is a risk that the internal pressure of the combustion chamber will not rise sufficiently and combustion of the gas generating agent will be interrupted. (That is, it is effective to adjust the splitting pressure of the seal tape in the portion that closes each of the plurality of gas ejection ports) so that it is opened in multiple stages according to the internal pressure of the combustion chamber.

Therefore, in order to stably obtain a desired gas output, it is essential that each of the plurality of gas ejection ports provided in the housing is accurately opened at a preset opening pressure. Become. The opening pressure of the gas ejection port is mainly determined by the opening area and peripheral length of the gas ejection port, the material and thickness of the sealing tape that closes the gas ejection port, and the like. It is preset to open at the desired pressure.

However, as in the disk-shaped gas generator 1A according to the present embodiment described above, when the flame is directed from the transfer chamber 35, a part of the first gas generating agent 51 is ignited and combustion starts locally, and the internal pressure and temperature rise sharply in a part of the first combustion chamber SA1.

As a result, the flow velocity of the generated gas locally becomes extremely high in a part of the inside of the housing, or the temperature rises locally in a part of the inside of the housing. In that case, a phenomenon occurs in which a part of the plurality of gas ejection ports 24 provided in the peripheral wall of the housing is opened by a pressure lower than the set opening pressure. obtain. If such a phenomenon occurs, there is a possibility that a desired gas output cannot be obtained.

For example, as shown in FIGS. 8(A) and 8(B), as in the above-described present embodiment, from the transfer chamber of the first igniter assembly 30 in the direction of the arrow AR1 in the figure (that is, , toward the central axis side of the housing), and the opening pressure of the plurality of gas ejection ports 24 provided in the peripheral wall portion 22 of the housing is set in two stages. . Here, the opening pressure of the gas ejection port 24a is set relatively low by adjusting the opening area to be large, and the opening area of the gas ejection port 24b is adjusted to be small. The opening pressure is set relatively high.

A disk-shaped gas generator 1A' according to the first configuration example shown in FIG. As viewed from the agent, a portion of the gas ejection ports provided in the portion directly facing the agent through the filter 70 is used as the gas ejection port 24a whose opening pressure is set relatively low, and the other gas ejection ports are set to be relatively low. When viewed from the first gas generating agent at the exit (the portion that directly receives the flame from the transfer chamber of the first igniter assembly 30 and is ignited), the exit is blocked by the combustion control member 37A and the second igniter assembly 40. ) is used as the gas ejection port 24b whose opening pressure is set relatively high.

In this case, the gas ejection port 24a, whose opening pressure is set relatively low, causes the flow velocity of the gas to locally extremely increase in the vicinity of the gas ejection port 24a, or the vicinity of the gas ejection port 24a. If the temperature rises locally in the region, or if both of these occur, there is a risk that the valve will be opened at a pressure lower than the set opening pressure. Therefore, when this configuration is employed, there is a possibility that the internal pressure of the first combustion chamber SA1 will not be sufficiently increased and the desired gas output will not be obtained, especially in a low temperature environment.

On the other hand, in the disk-shaped gas generator 1A″ according to the second configuration example shown in FIG. When viewed from the gas generating agent, the gas ejection port provided in the portion directly facing the gas generating agent through the filter 70 is assumed to be the gas ejection port 24b whose opening pressure is set relatively high, and the first igniter assembly 30 When viewed from the portion of the first gas generating agent that is ignited by directly receiving the flame from the transfer chamber, the gas ejection port of the portion blocked by the combustion control member 37A and the second igniter assembly 40 is opened. The gas ejection port 24a is set to have a relatively low pressure.

In this case, the gas ejection port 24a, whose opening pressure is set relatively low, causes the flow velocity of the gas to locally extremely increase in the vicinity of the gas ejection port 24a, or the vicinity of the gas ejection port 24a. Since there is no possibility that the temperature rises locally in the region or both of them occur, there is no risk of opening due to a pressure lower than the set opening pressure. On the other hand, the gas ejection port 24b, whose opening pressure is set relatively high, causes the flow velocity of the gas to locally extremely increase in the vicinity of the gas ejection port 24b, or Although there is a possibility that the temperature may rise extremely locally or both of these may occur, the opening pressure is set relatively high in the first place, so it is almost unaffected and It will be opened at the set opening pressure.

Therefore, in the case of the disk-shaped gas generator 1A according to the present embodiment, a plurality of gases are generated like the disk-shaped gas generator 1A'' according to the second configuration example shown in FIG. 8B. Of the jets 24, the gas jets located on the side opposite to the central axis side of the housing as seen from the transfer chamber and the gas jets blocked by the second igniter assembly 40 as seen from the transfer chamber (that is, , the gas outlet indicated by reference numeral 24a in the drawing) is preferably set lower than the opening pressure of the other gas outlets (that is, the gas outlet indicated by reference numeral 24b in the drawing).

The present inventor actually produced a disk-shaped gas generator 1A' according to the first structural example and a disk-shaped gas generator 1A'' according to the second structural example, and found that the opening pressure of the gas ejection port was Experiments were carried out to confirm what kind of difference occurred.Here, the opening pressure of the gas ejection port 24a, whose opening pressure is set relatively low, was set to 7.2 [MPa], and the opening pressure The opening pressure of the gas ejection port 24b, which is set relatively high, was set to 10 [MPa].

As a result, in the disk-type gas generator 1A' according to the first configuration example, the measured value of the opening pressure of the gas ejection port 24a, which was set to 7.2 [MPa] as the set value, was 6 on average. 0.8 [MPa], and the measured value of the opening pressure of the gas ejection port 24b, whose opening pressure is set to 10 [MPa], becomes 8.2 [MPa] on average, and the second configuration example In the disc-shaped gas generator 1A″, the measured value of the opening pressure of the gas ejection port 24a, which is set to the set value of 7.2 [MPa], is 7.6 [MPa] on average. The measured value of the opening pressure of the gas ejection port 24b, which was set to 10 [MPa] as the set value, was 8.8 [MPa] on average.

That is, by using the disk-type gas generator 1A″ according to the second configuration example, the gas ejection port 24 is in a state closer to the set value than in the case of the disk-type gas generator 1A′ according to the first configuration example. was experimentally confirmed to be released in multiple stages. Therefore, by adopting a configuration such as the disk-type gas generator 1A'' according to the second configuration example, it is difficult to be affected by the surrounding environment. It is possible to obtain a disk-type gas generator capable of obtaining a more stable gas output.

FIG. 9 is a perspective view of combustion control members according to first to fifth modifications. Hereinafter, with reference to FIG. 9, some of possible modifications of the combustion control member in the disk-shaped gas generator 1A according to the present embodiment will be described.

In a combustion control member 37A1 according to a first modification shown in FIG. 9A, the opening angle of the open portion 37b in the circumferential direction of the combustion control member 37A1 is set to approximately 180°, and the upper end of the combustion control member 37A1 It is configured to reach the upper end opening of the.

In a combustion control member 37A2 according to a second modification shown in FIG. 9B, the opening angle of the open portion 37b in the circumferential direction of the combustion control member 37A2 is gradually increased from the lower end to the upper end, and is about 120 degrees at the lower end. ° and about 180° at the upper end so that the upper end reaches the upper end opening of the combustion control member 37A2.

In a combustion control member 37A3 according to a third modification shown in FIG. 9C, the opening angle of the opening portion 37b in the circumferential direction of the combustion control member 37A3 is set to about 120°, and the opening portion 37b is set to the barrier portion 37a. It is formed in the shape of a window.

In a combustion control member 37A4 according to a fourth modification shown in FIG. 9D, the opening angle of the opening portion 37b in the circumferential direction of the combustion control member 37A4 is set to about 180°, and the opening portion 37b is set to the barrier portion 37a. It is formed in the shape of a window.

A combustion control member 37A5 according to a fifth modification shown in FIG. 9(E) is arranged such that two open portions 37b are arranged side by side in the circumferential direction of the combustion control member 37A5, and the opening angle of each open portion 37b is set to The angle is set to approximately 60°, and these two openings 37b are formed in the barrier portion 37a in the form of windows.

Even when the combustion control members 37A1 to 37A5 according to the first to fifth modifications are used, effects similar to those of the combustion control member 37A according to the present embodiment can be obtained.

(Embodiment 2)
FIG. 10 is a schematic diagram of a disk-type gas generator according to Embodiment 2, and FIG. 11 is a perspective view of the combustion control member shown in FIG. A disk-type gas generator 1B according to the present embodiment will be described below with reference to FIGS. 10 and 11. FIG. The disk-shaped gas generator 1B according to the present embodiment also has a so-called dual structure, like the disk-shaped gas generator 1A according to the first embodiment.

As shown in FIGS. 10 and 11, the disk-shaped gas generator 1B according to the present embodiment has a lower combustion control member 37A than the disk-shaped gas generator 1A according to the first embodiment. (see FIG. 1, etc.), and the structure of assembling the combustion control member 37B to the bottom plate portion 11 is different. .

Specifically, the combustion control member 37B has a substantially cylindrical shape with a bottom, and has a barrier portion 37a, an open portion 37b, and a flange portion 37e. The combustion control member 37B is made of a non-brittle member that does not explode or melt when the transfer charge 36 burns, and is made of metal such as stainless steel or steel. In addition, the combustion control member 37A may be made of a heat-resistant resin having a melting point exceeding 300[° C.]. Examples of the heat-resistant resin include polyimide resin and polyamide resin.

The combustion control member 37B is arranged so that its axial direction is parallel to the axial direction of the housing. , and is fixed to the first holder 31 by bending the crimped portion 31 e provided on the first holder 31 . That is, the combustion control member 37B is fixed to the first holder 31 by crimping, and is assembled to the bottom plate portion 11 via the first holder 31. As shown in FIG.

Along with this, the end portion of the cup body 34 on the side of the bottom plate portion 11 is not provided with a flange portion, and the cup body 34 is provided inside the above-described crimped portion 31e of the first holder 31. Extrapolated to the protrusion. Thereby, the cup body 34 is fixed to the first holder 31 by being covered with the combustion control member 37B.

The combustion control member 37B, like the combustion control member 37A described above, provides directivity so that the flame generated by burning the transfer charge 36 is ejected from the transfer chamber 35 in a predetermined direction. The function of imparting directivity to the flame generated by burning the transfer charge 36 is mainly exhibited by the barrier portion 37a and the open portion 37b provided in the combustion control member 37B.

That is, the barrier portion 37a is located on the opposite side of the top wall portion 34a and the side wall portion 34b of the cup body 34 defining the transfer chamber 35 from the portion located near the central axis of the housing. The opening 37b is positioned so as to directly cover the side wall portion 34b of the portion located near the center axis of the housing so as to expose the side wall portion 34b of the portion located near the central axis of the housing. Here, in FIG. 11, an arrow A indicates the direction in which the central axis of the housing is located when viewed from the combustion control member 37B. In the combustion control member 37B according to the present embodiment, the opening angle of the open portion 37b in the circumferential direction of the combustion control member 37B is set to approximately 120°, and the open portion 37b is formed in the barrier portion 37a in a window shape. It is what I did.

As a result, when the transfer charge 36 burns, the portion of the side wall portion 34b of the cup body 34 exposed by the open portion 37b bursts or melts due to the combustion of the transfer charge 36. A flame generated by burning the explosive 36 is spouted into the first combustion chamber SA1 in a predetermined direction (that is, toward the central axis of the housing).

Therefore, even in the case of the disk-type gas generator 1B according to the present embodiment, the same effect as in the case of the above-described first embodiment can be obtained, and the first igniter 32 is arranged eccentrically. Also in this case, the first gas generating agent 51 can be efficiently burned, and the manufacturing cost can be reduced.

(Embodiment 3)
FIG. 12 is a schematic diagram of a disk-type gas generator according to Embodiment 3. FIG. A disk-shaped gas generator 1C according to the present embodiment will be described below with reference to FIG. The disk-shaped gas generator 1C according to the present embodiment has a so-called single structure, unlike the disk-shaped gas generator 1A according to the first embodiment.

As shown in FIG. 12, the disk-shaped gas generator 1C according to the present embodiment has a second igniter assembly 40 (Fig. 1 etc.) is not provided, the main difference is in the configuration. Along with this, the space inside the housing and inside the filter 70 is defined as a combustion chamber SA in which the first gas generating agent 51 is accommodated.

The first igniter assembly 30 is eccentrically arranged so that its central axis does not overlap the central axis of the peripheral wall of the housing, and the first gas generating agent 51 is positioned around the first igniter assembly 30. are doing. The combustion control member 37A has the same configuration as the combustion control member 37A (see FIG. 3, etc.) in the above-described first embodiment, and is arranged in the combustion chamber SA so that its axial direction is parallel to the axial direction of the housing. placed inside.

The barrier portion 37a of the combustion control member 37A is formed at a portion of the top wall portion 34a and the side wall portion 34b of the cup body 34 defining the transfer chamber 35, which is located on the opposite side of the portion located near the central axis of the housing. The open portion 37b of the combustion control member 37A is positioned so as to directly cover the side wall portion 34b, and the opening portion 37b of the combustion control member 37A exposes the top wall portion 34a and the portion of the side wall portion 34b located near the central axis of the housing. positioned.

As a result, in the portion where the barrier portion 37a of the combustion control member 37A is located, the side wall portion 34b of the cup body 34 does not directly face the first gas generating agent 51, and the barrier portion 37a is interposed therebetween. ing.

With this configuration, when the transfer charge 36 is burned, the portions of the top wall portion 34a and the side wall portion 34b of the cup body 34 exposed by the open portion 37b burst due to the combustion of the transfer charge 36. Alternatively, it melts, and the flame generated by the combustion of the transfer charge 36 blows out in a predetermined direction (that is, toward the central axis of the housing) into the combustion chamber SA.

Therefore, even in the case of the disk-shaped gas generator 1C according to the present embodiment, it is possible to obtain the same effects as in the case of the above-described first embodiment, and the configuration in which the first igniter 32 is arranged eccentrically. Also in this case, the first gas generating agent 51 can be efficiently burned, and the manufacturing cost can be reduced.

FIG. 13 is a conceptual diagram showing a configuration example of a gas ejection port in the disk-shaped gas generator according to this embodiment. Hereinafter, a disk-shaped gas generator 1C' according to this configuration example will be described with reference to FIG.

A disc-type gas generator 1C' according to this configuration example shown in FIG. , and the gas ejection port provided in the portion directly facing this through the filter 70 is the gas ejection port 24b whose opening pressure is set relatively high, and the gas from the transfer chamber of the first igniter assembly 30 When viewed from the portion of the first gas generating agent that directly receives the flame and ignites, the gas ejection port of the portion blocked by the combustion control member 37A is replaced with the gas ejection port 24a whose opening pressure is set relatively high. It is what I did.

By configuring in this way, the gas ejection port 24a, whose opening pressure is set relatively low, causes the flow velocity of the gas to locally extremely increase in the vicinity of the gas ejection port 24a, or the gas to flow. Since the temperature does not rise extremely locally in the vicinity of the ejection port 24a, and both of these do not occur, the risk of opening due to a pressure lower than the set opening pressure is eliminated. . On the other hand, the gas ejection port 24b, whose opening pressure is set relatively high, causes the flow velocity of the gas to locally extremely increase in the vicinity of the gas ejection port 24b, or Although there is a possibility that the temperature may rise extremely locally or both of these may occur, the opening pressure is set relatively high in the first place, so it is almost unaffected and It will be opened at the set opening pressure.

Therefore, in the case of the disk-shaped gas generator 1C according to the present embodiment, as in the disk-shaped gas generator 1C' according to the present configuration example, when viewed from the transfer chamber of the plurality of gas ejection ports 24, The opening pressure of the gas ejection port located on the side opposite to the central axis side of the housing (that is, the gas ejection port indicated by reference numeral 24a in the figure) is increased by the opening pressure of the other gas ejection port (namely, indicated by reference numeral 24b in the figure). It is preferably set lower than the opening pressure of the gas ejection port). By configuring in this way, it is possible to make the disc-type gas generator less susceptible to the influence of the surrounding environment and to obtain a more stable gas output.

(Other forms, etc.)
In Embodiments 1 and 2 of the present invention and their modifications described above, the first igniter and the second igniter are energized at different timings, so that the second igniter Although the explanation has been given by exemplifying the case where they are configured to operate at timings delayed from , they may be configured to operate at the same timings by energizing them at the same timings. Further, even when the first igniter and the second igniter are energized at the same timing, by providing a delay charge for delaying the ignition of the ignition charge in the ignition part of the second igniter, the second igniter The time required from the energization of the igniter to the ignition of the ignition charge is extended, thereby energizing the first igniter and the second igniter at the same timing, while setting the timing of the start of combustion of the second gas generating agent to the first It may be configured to delay the timing of starting combustion of the gas generating agent.

Further, in the above-described first and second embodiments of the present invention and their modifications, the case where both the first combustion chamber and the second combustion chamber are filled with the gas generating agent has been described as an example. The second combustion chamber may be used as a transfer chamber, and the transfer charge may be filled in the transfer chamber. In this configuration, the second igniter is actuated to burn the transfer charge, and the combustion of the transfer charge generates a large amount of heat particles inside the transfer chamber and the transfer charge. Firebox pressure rises. As a result, the cap member and the cup member move toward the top plate portion, and the gas passage holes provided in the cap member are exposed so as to face the first combustion chamber. 1 into the combustion chamber. Therefore, when this configuration is adopted, the combustion of the first gas generating agent can be accelerated by the transfer charge filled inside the partition portion composed of the partition member, the cup member, and the cap member.

Further, in the above-described first to third embodiments of the present invention and their modifications, the case where the igniter is assembled to the bottom plate portion of the housing via a metal holder has been described as an example. However, the igniter may be assembled to the bottom plate of the housing by so-called insert molding.

Furthermore, the characteristic configurations shown in the first to third embodiments of the present invention and their modifications described above can be combined with each other as long as they do not deviate from the gist of the present invention.

Thus, the above-described embodiments and their modifications disclosed this time are illustrative in all respects and are not restrictive. The technical scope of the present invention is defined by the scope of claims, and includes all changes within the meaning and scope of equivalents to the description of the scope of claims.

1A to 1C, 1A', 1A'', 1C' disk-type gas generator, 10 lower shell, 11 bottom plate, 11a first opening, 11b second opening, 12 peripheral wall, 20 upper shell, 21 top plate portion, 22 peripheral wall portion, 23 flange portion, 24, 24a, 24b gas outlet, 25 sealing tape, 30 first igniter assembly, 31 first holder, 31a upper recess portion, 31b lower recess portion, 31c through hole, 31d, 31e crimped portion, 32 first igniter, 32a base portion, 32b ignition portion, 32c terminal pin, 33 first sealing member, 34 cup body, 34a top wall portion, 34b side wall portion, 34c flange portion, 35 fire chamber , 36 transfer charge, 37A, 37A1 to 37A5, 37B combustion control member, 37a barrier portion, 37b opening portion, 37c fixed portion, 37d holding portion, 37e flange portion, 40 second igniter assembly, 41 second holder, 41a Upper concave portion 41b Lower concave portion 41c Through hole 41d Crimped portion 42 Second igniter 42a Base portion 42b Ignition portion 42c Terminal pin 43 Second seal member 44 Partition portion 45 Partition member 45a Cover Fixed part 46 Cover member 46a First cover part 46b Second cover part 47 Cap member 47a Top plate part 47b Peripheral plate part 47c Gas passage hole 51 First gas generating agent 52 Second gas generating agent , 61 lower support member, 62 upper support member, 63 cushion material, 70 filter, SA combustion chamber, SA1 first combustion chamber, SA2 second combustion chamber, SB gas discharge chamber.

Claims (3)

A substantially cylindrical peripheral wall portion provided with a plurality of gas ejection ports, a top plate portion closing one end in the axial direction of the peripheral wall portion, and a bottom plate portion closing the other end in the axial direction of the peripheral wall portion, a housing having therein a combustion chamber containing a gas generating agent;
a substantially cylindrical filter housed inside the housing so as to surround the combustion chamber;
an igniter that is assembled to the bottom plate and includes an igniter containing an ignition charge that ignites when activated;
The igniter has a top wall portion and a side wall portion defining a transfer chamber containing a transfer charge, and the transfer chamber protrudes toward the combustion chamber side so as to face the ignition portion. a cup body made of a fragile member that bursts or melts due to combustion of the transfer charge accompanying the operation of
a combustion control member made of a non-brittle member that does not burst or melt even when the transfer charge is burned, and is arranged in the combustion chamber to control the spread of flames of the gas generating agent that is ignited by the combustion of the transfer charge; with
The filter is arranged coaxially with the housing such that the central axis of the filter overlaps the central axis of the peripheral wall,
The cup body is arranged eccentrically with respect to the central axis of the peripheral wall,
The gas generating agent is arranged in a space inside the filter and adjacent to the top wall portion and the side wall portion so as to be positioned around the cup body ,
The combustion control member exposes at least a portion of a portion of the side wall portion located near the center axis of the peripheral wall portion and the top wall portion , and exposes the top wall portion of the side wall portion near the center axis of the peripheral wall portion. A gas generator having a shape that directly covers a portion located on the opposite side of the portion located on the side without intervening the gas generating agent. Further comprising a holder fixed to the bottom plate portion and holding the igniter,
2. The gas generator of claim 1, wherein said combustion control member is secured to said holder. the holder is positioned so as to protrude from the bottom plate toward the combustion chamber;
The combustion control member has a cylindrical fixed portion,
3. The gas generator according to claim 2, wherein said fixed portion is press-fitted into said holder.

Images