JP2021006447A - Gas generator - Google Patents

Abstract

To provide a gas generator configured so that an igniter is eccentrically arranged therein, which stably enables desired gas output.SOLUTION: A gas generator 1A comprises: a housing having a peripheral wall part 22 in which a plurality of gas jetting ports 24 are arranged along a circumferential direction with intervals from each other; a cup body 34A defining an inflammation chamber 35 provided to face an igniter 32; and a burning control mechanism 37 that controls spreading of fire of a gas generating agent 51 that is ignited by burning of an inflammation chemical 36 housed in the inflammation chamber 35. The cup body 34A is eccentrically arranged with respect to a center shaft of the peripheral wall part 22, and the burning control mechanism 37 gives directivity so that flame generated by burning of the inflammation chemical 36 is blown out from the inflammation chamber 35 toward the center shaft of the peripheral wall part 22. Opening pressure of the gas jetting port positioned at the opposite side of the center shaft side of the peripheral wall part 22 of the plurality of gas jetting ports 24, when viewed from the inflammation chamber 35 is set to be lower than opening pressure of the other gas jetting port of the plurality of gas jetting ports 24.SELECTED DRAWING: Figure 5

Description

The present invention relates to a gas generator incorporated in an occupant protection device that protects an occupant in the event of a collision with a vehicle or the like, and more particularly to a gas generator incorporated in an airbag device installed in an automobile or the like.

Conventionally, from the viewpoint of protecting occupants of automobiles and the like, airbag devices, which are occupant protection devices, have become widespread. The airbag device is equipped for the purpose of protecting the occupant from the impact generated in the event of a vehicle collision. By instantly inflating and deploying the airbag in the event of a vehicle collision, the airbag acts as a cushion for the occupant. It catches the body.

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

There are various types of gas generators, but as a gas generator that is particularly preferably incorporated into a driver-seat airbag device, a passenger-seat airbag device, or the like, a short abbreviation circle having a relatively large outer diameter. There is a columnar disc type gas generator. This disk-type gas generator also has various structures, and is associated with a single structure having only one combustion chamber and one igniter, two combustion chambers, and these two combustion chambers. There is a dual structure having two igniters provided in the above.

In these single-structured disc-type gas generators and dual-structured disc-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 often found in dual-type gas generators, and as a document in which a disc-type gas generator in which such a configuration is disclosed is disclosed, for example, Japanese Patent Application Laid-Open No. 2009-517263 (Japanese Patent Publication No. 2009-517263). There is Patent Document 1).

Special Table 2009-517263

Generally, in a gas generator, an explosive is loaded between the igniter and the gas generator so that all gas generators will burn during operation. Here, in the gas generator in which the igniter is eccentrically arranged as described above, the igniter is eccentrically arranged, so that the igniter is arranged around the gas generator when viewed from the firebox in which the explosive is housed. The amount of gas generator produced will be biased depending on the direction.

Therefore, conventionally, the cup body that defines the firebox is composed of a non-fragile member provided with a communication hole, and the position where the communication hole is formed is appropriately set to burn the firebox. The gas generator is ignited efficiently by giving directivity to the direction in which the flame generated by the fire is ejected from the firebox.

Here, the output characteristics of the gas generator are influenced by the surrounding environment in which the gas generator is placed, and particularly depend on the environmental temperature, the output characteristics are strengthened in a high temperature environment, and the output characteristics are in a low temperature environment. It tends to weaken. 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 faster, and the gas is ejected faster and more strongly. In the low temperature environment, the gas generating agent By suppressing the combustion of the gas, the rise in the internal pressure of the combustion chamber becomes slower, and the gas is ejected slower and weaker.

Therefore, especially in a low temperature environment, the internal pressure of the combustion chamber may not rise sufficiently and the combustion of the gas generating agent may be interrupted. In order to prevent this, the open pressure of a plurality of gas outlets provided in the housing may be interrupted. It is effective to adjust (that is, the opening pressure of the sealing tape at the portion that closes each of the plurality of gas outlets) so that this is opened in multiple stages according to the internal pressure of the combustion chamber.

Therefore, in order to stably obtain the desired gas output, it is indispensable that each of the plurality of gas outlets provided in the housing is accurately opened at a preset opening pressure. Become.

However, as described above, when the igniter is an eccentric gas generator, a part of the gas generator is ignited locally by the flame ejected from the combustion chamber with directivity. Combustion will start at the beginning, and the internal pressure and temperature will rise sharply in a part of the combustion chamber.

Therefore, the flow velocity of the generated gas becomes extremely fast locally in a part of the inside of the housing, or the temperature rises extremely locally in a part of the inside of the housing. As a result, a part of the gas outlet provided on the peripheral wall portion of the housing may be opened by a pressure lower than the set opening pressure. When such a phenomenon occurs, the desired gas output may not be obtained.

Therefore, the present invention has been made in view of the above-mentioned problems, and an object of the present invention is to ensure that a desired gas output can be stably obtained in a gas generator in which an igniter is eccentrically arranged.

The gas generator based on the present invention includes a housing, a filter, an igniter, a cup body, and a combustion control mechanism. The housing has a substantially cylindrical peripheral wall portion provided with a plurality of gas outlets, a top plate portion that closes one end of the peripheral wall portion in the axial direction, and a bottom plate that closes the other end of the peripheral wall portion in the axial direction. It has a combustion chamber inside which contains a gas generating agent. The filter is composed of 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 igniting agent that ignites during operation. The cup body defines a firebox in which the explosive is housed, and is arranged so as to project toward the combustion chamber side so that the firebox faces the ignition portion. The combustion control mechanism controls the spread of the gas generating agent ignited by the combustion of the explosive. The plurality of gas outlets are located at intervals from each other along the circumferential direction of the peripheral wall portion. 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 combustion control mechanism provides directivity so that a flame generated by burning the explosive is ejected from the firebox toward the central axis side of the peripheral wall portion. The opening pressure of the gas outlet located on the side opposite to the central axis side of the peripheral wall portion when viewed from the firebox among the plurality of gas outlets is the other gas among the plurality of gas outlets. It is set lower than the opening pressure of the spout.

In the gas generator based on the present invention, the cup body has a top wall portion and a side wall portion that define the fire transmission chamber, and the cup body bursts or bursts due to the combustion of the transmission agent accompanying the operation of the igniter. It may be composed of a fragile member that melts. In that case, the combustion control mechanism may be arranged in the combustion chamber and may be composed of a combustion control member made of a non-fragile member that does not burst or melt even when the explosive is burned. Further, in that case, the combustion control member exposes at least a part of the side wall portion located near the central axis of the peripheral wall portion, and at the same time, the center of the peripheral wall portion of the side wall portion. It is preferable to have a shape that directly covers the portion located on the side opposite to the portion located near the axis without interposing the gas generating agent.

In the gas generator based on the present invention, the combustion control mechanism is composed of a communication hole or a score provided in a portion of the cup body located near the central axis of the peripheral wall portion. May be good.

According to the present invention, a desired gas output can be stably obtained in a gas generator in which the igniters are eccentrically arranged.

It is the schematic of the disk type gas generator which concerns on Embodiment 1. FIG. It is a schematic cross-sectional view along the line II-II shown in FIG. It is a perspective view of the combustion control member shown in FIG. It is an exploded perspective view which shows the assembly structure of the partition part shown in FIG. It is a schematic cross-sectional view which shows the 1st stage in operation of the disk type gas generator shown in FIG. It is a schematic cross-sectional view along the VI-VI line shown in FIG. It is a schematic cross-sectional view which shows the 2nd stage at the time of operation of the disk type gas generator shown in FIG. It is a conceptual diagram which shows the structural example of the gas outlet in the disk-type gas generator which concerns on a comparative example, and the structural example of the gas-outlet in the disk-type gas generator which shows Embodiment 1. It is a perspective view of the combustion control member which concerns on 1st to 6th modification. It is the schematic of the disk type gas generator which concerns on Embodiment 2. FIG. It is a perspective view of the cup body shown in FIG. It is a conceptual diagram which shows the structural example of the gas outlet in the disk-type gas generator shown by Embodiment 2. FIG. It is a perspective view of the cup body which concerns on 7th to 9th modification. It is the schematic of the disk type gas generator which concerns on Embodiment 3. FIG. It is a conceptual diagram which shows the structural example of the gas outlet in the disk type gas generator shown in FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The following embodiments are applications of the present invention to a disc-type gas generator that is suitably incorporated into 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 designated by the same reference numerals in the drawings, and the description thereof will not be repeated.

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

As shown in FIGS. 1 and 2, the disc-type gas generator 1A has a short substantially cylindrical housing in which one end and the other end in the axial direction are closed, and the housing provided inside the housing is provided. In the space, the first igniter assembly 30, the second igniter assembly 40, the first gas generator 51, the second gas generator 52, the lower support member 61, the upper support member 62, and the filter as internal components. 70 etc. are housed.

As shown in FIG. 1, the housing includes a lower shell 10 and an upper shell 20. Each of the lower shell 10 and the upper shell 20 is made of a press-formed product formed by, for example, pressing a rolled metal plate-like member. As the metal plate-like member constituting the lower shell 10 and the upper shell 20, for example, a metal plate made of stainless steel, steel, aluminum alloy or the like is used, and preferably 440 [MPa] or more and 780 [MPa]. A so-called high-tensile steel plate that does not break or break 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 the housing is formed by combining and joining these opening surfaces so as to face 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 to each other at or near their contact portions, whereby the lower shell 10 and the upper shell 20 are fixed. ing. Here, electron beam welding, laser welding, friction welding and the like can be preferably used for joining the lower shell 10 and the upper shell 20.

As a result, the portion of the peripheral wall portion of the housing near the bottom plate portion 11 is composed of 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 on the upper side. It is composed of a peripheral wall portion 22 of the shell 20. Further, one end and the other end in the axial direction 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.

The flange portion 23 provided on the upper shell 20 is a portion for fixing the disc type gas generator 1A to an external member (for example, a retainer provided in the airbag device). A through hole (the through hole does not appear in the drawing) is provided at a predetermined position of the flange portion 23 so as to penetrate along a direction parallel to the axial direction of the peripheral wall portion 22. A fastening member such as a bolt is inserted into the through hole, whereby the disc type gas generator 1A is fixed to the external member.

A first opening 11a and a second opening 11b are provided at predetermined positions of the bottom plate portion 11 of the lower shell 10. 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 11a, and a second igniter is attached so as to close the second opening 11b. The assembly 40 is assembled. Here, the first opening 11a is a portion for exposing the first female connector portion, which will 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 the 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 34A, a gunpowder 36, and a combustion control member 37. The first holder 31 constitutes the base of the first igniter assembly 30, and the first igniter 32, the cup body 34A, the combustion control member 37, and the like are assembled to the first holder 31. , The first igniter assembly 30 is configured as an integral part.

The first holder 31 is made of a member having a substantially columnar outer shape, and is made of a metal member such as stainless steel, steel, or an aluminum alloy. An upper recess 31a is provided on the upper surface of the first holder 31 located on the top plate portion 21 side, and a lower recess 31b is provided on the lower surface of the first holder 31 located on the bottom plate portion 11 side. There is. Further, the first holder 31 of the portion forming the bottom of the upper recess 31a and the bottom of the lower recess 31b is provided with a through hole 31c so as to reach the upper recess 31a and the lower recess 31b.

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

The first igniter 32 is for generating a flame, and has a base portion 32a, an ignition portion 32b, and a pair of terminal pins 32c. The base portion 32a is a portion that holds the ignition portion 32b and the pair of terminal pins 32c, and is also a portion that is fixed to the first holder 31. The ignition unit 32b includes an igniting agent that ignites and burns during operation to generate a flame, and a resistor (bridge wire) for igniting the igniting agent. The pair of terminal pins 32c are connected to the ignition unit 32b to ignite the ignition charge.

More specifically, the ignition portion 32b includes a cup-shaped squib cup and an embolus that closes the open end of the squib cup and a pair of terminal pins 32c is inserted and held therein. The above-mentioned resistor is attached so as to connect the tips of the pair of terminal pins 32c inserted in the squib cup, and the igniter is placed in the squib cup so as to surround or approach the resistor. It has a loaded configuration.

Here, nichrome wire or the like is generally used as the resistor, and ZPP (zirconium / potassium perchlorate), ZWPP (zirconium / tungsten / potassium perchlorate), lead styphnate or the like is generally used as the ignition agent. The squib cup and embolus described above are generally made of metal or plastic.

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

In the first igniter 32, a 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 and fastened in the upper recess 31a of the first holder 31. The crimped portion 31d described above is fixed to the first holder 31 by being bent.

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, whereby the first holder 31 and the first igniter 32 are connected to each other. The airtightness in the portion is ensured by closing the gap between them. The fixing method of the first igniter 32 is not limited to the fixing method using the caulking portion 31d described above, and other fixing methods may be used.

The cup body 34A has a cup-like shape in which the end portion on the bottom plate portion 11 side is open, and includes a fire transmission chamber 35 in which the fire transmission agent 36 is housed. The cup body 34A has a top wall portion 34a and a side wall portion 34b that define the firebox 35, and a flange portion 34c that extends radially outward from a portion of the side wall portion 34b on the opening end side. There is.

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

The cup body 34A does not have an opening in either the top wall portion 34a or the side wall portion 34b, and surrounds the fire transmission chamber 35 provided inside the cup body 34A. The cup body 34A is from a fragile member that bursts or melts as the pressure rises in the fire transmission chamber 35 and the conduction of the generated heat when the fire transmission agent 36 is ignited by the operation of the first igniter 32. Become.

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

The explosive charge 36 filled in the fire transmission room 35 is ignited by a flame generated by the operation of the first igniter 32, and burns to generate heat particles. The explosive agent 36 needs to 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 ). _A composition composed of a metal powder / oxidizing agent typified by ₂ or the like, a composition composed of titanium hydride / potassium perchlorate, a composition composed of B / 5-aminotetrazole / potassium nitrate / molybdenum trioxide, etc. are used. ..

As the explosive agent 36, a powdery one, a one molded into a predetermined shape by a binder, or the like is used. The shape of the fire-transmitting agent 36 formed by the binder includes various shapes such as granular shape, columnar shape, sheet shape, spherical shape, single-hole cylindrical shape, porous cylindrical shape, and tablet shape.

As shown in FIGS. 1 to 3, the combustion control member 37 has a substantially cylindrical shape, and has a barrier portion 37a, an opening portion 37b, a fixed portion 37c, and a pressing portion 37d. ing. The combustion control member 37 is made of a non-fragile member that does not burst or melt even when the explosive is burned, and is made of a metal member such as stainless steel or steel. In addition to this, the combustion control member 37 may be composed of a heat-resistant resin having a melting point of more than 300 [° C.], and examples of the heat-resistant resin include polyimide resin and polyamide resin.

The combustion control member 37 is arranged so that its axial direction is parallel to the axial direction of the housing, and the opening end located on the bottom plate portion 11 side is fixed to the first holder 31 assembled to the bottom plate portion 11. It functions as a fixed portion 37c. More specifically, the fixed portion 37c has a substantially cylindrical shape, and the portion where the fixed portion 37c is located so as to project from the bottom plate portion 11 toward the first combustion chamber SA1 side described later. By press-fitting into the first holder 31, the combustion control member 37 is assembled to the bottom plate portion 11 via the first holder 31.

The combustion control member 37 corresponds to a combustion control mechanism that controls the spread of the first gas generating agent 51, which will be described later, which is ignited by the combustion of the transmission agent 36. More specifically, the flame generated by the combustion of the transmission agent 36 Gives directionality so that the fire is ejected from the fire transmission chamber 35 in a predetermined direction. The function of giving directivity to the flame generated by the combustion of the explosive charge 36 is mainly exerted by the barrier portion 37a and the opening portion 37b provided in the combustion control member 37.

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

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

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

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 is inserted with respect to the bottom plate portion 11. It is fixed by being joined. As a result, the first igniter assembly 30 integrated by assembling the first igniter 32, the cup body 34A, the combustion control member 37, etc. to the first holder 31 in advance is attached to the lower shell 10. Will be fixed.

Therefore, the first holder 31 is configured to be positioned so as to project from the bottom plate portion 11 toward the space inside the housing, and in particular, the firebox provided inside the first igniter assembly 30. 35 will be placed in the space inside the housing. Here, electron beam welding, laser welding, friction welding, and the like can be suitably used for joining the bottom plate portion 11 and the first holder 31.

A pair of terminal pins 32c of the first igniter 32 are exposed and located in the lower recess 31b of the first holder 31. As a result, the lower concave portion 31b and the pair of terminal pins 32c form the above-mentioned 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 toward 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. Continuity 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. Includes. The second holder 41 constitutes the base of the second igniter assembly 40, and the second igniter 42, the partition portion 44, and the like are assembled to the second holder 41 to form the second igniter. The assembly 40 is configured as an integral part.

The second holder 41 is made of a member having a substantially columnar outer shape, and is made of a metal member such as stainless steel, steel, or an aluminum alloy. An upper recess 41a is provided on the upper surface of the second holder 41 located on the top plate portion 21 side, and a lower recess 41b is provided on the lower surface of the second holder 41 located on the bottom plate portion 11 side. There is. Further, the second holder 41 of the portion forming the bottom of the upper recess 41a and the bottom of the lower recess 41b is provided with a through hole 41c so as to reach the upper recess 41a and the lower recess 41b.

Further, a caulking portion 41d is provided on the upper surface of the second holder 41 so as to surround the upper recess 41a. The caulking portion 41d is a portion for caulking and fixing the second igniter 42 to the second holder 41.

The second igniter 42 is for generating a flame, and has a base portion 42a, an ignition portion 42b, and a pair of terminal pins 42c. The base portion 42a is a portion that holds the ignition portion 42b and the pair of terminal pins 42c, 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.

The second igniter 42 has a pair of terminal pins 42c inserted into the through holes 41c of the second holder 41 from above, and the base portion 42a is accommodated and fastened in the upper recess 41a of the second holder 41. The crimped portion 41d described above is fixed to the second holder 41 by being bent.

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, whereby the second holder 41 and the second igniter 42 are connected to each other. The airtightness in the portion is ensured by closing the gap between them. The fixing method of the second igniter 42 is not limited to the fixing method using the caulking portion 41d described above, and other fixing methods may be used.

The partition portion 44 has a partition wall member 45, a cover member 46, and a cap member 47, and the partition wall member 45, the cover member 46, and the cap member 47 are combined to form a cup-like shape as a whole. doing. The partition 44 functions as a pressure partition partitioning the combustion chamber, which is the space inside the housing and the space 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 formed by the partition 44 from the space outside the partition 44 and from the partition 44. Is also partitioned into an inner space, of which the former space is defined as the first combustion chamber SA1 and the latter space of which is defined as the second combustion chamber SA2.

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

The second gas generating agent 52 is housed in the second combustion chamber SA2 located inside the partition portion 44. The second gas generating agent 52 is an agent that generates gas by being ignited by heat particles generated by the operation of the second igniter 42 and burning. The details of the second gas generating agent 52 will be described later.

As shown in FIGS. 1, 2 and 4, the partition wall member 45 has a tubular shape having openings at both ends in the axial direction. The partition wall member 45 is arranged so that its axial direction is parallel to the axial direction of the housing, and the opening end located on the bottom plate portion 11 side is fixed to the second holder 41 assembled to the bottom plate portion 11. It functions as a fixed portion 45a.

More specifically, the fixed portion 45a is press-fitted into the second holder 41 as described above, whereby the partition member 45 is fixed to the second holder 41, so that the partition portion including the partition member 45 is included. 44 is assembled to the bottom plate portion 11. The partition wall member 45 is made of a metal member such as stainless steel, steel, or an aluminum alloy.

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

The cover member 46 is formed from a disk-shaped first covering portion 46a that forms a closed end of the partition portion 44 by covering an opening located on the top plate portion 21 side of the partition wall member 45, and from the peripheral edge of the first covering portion 46a. A cylindrical second covering portion 46b that covers the outer peripheral surface of the portion of the partition wall member 45 near the top plate portion 21 by extending toward the bottom plate portion 11 side is included.

The cover member 46 is attached to the partition member 45 by being externally inserted into the above-mentioned opening end of the partition member 45, and is preferably fixed to the partition member 45 by press fitting. As a result, the second covering portion 46b of the cover member 46 is in close contact with the above-mentioned outer peripheral surface of the partition wall member 45.

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 wall member 45 near the top plate portion 21. As a result, the cap member 47 is housed in the space defined by the partition member 45 and the cover member 46 (that is, corresponding to the second combustion chamber SA2). Like the partition wall member 45, the cap member 47 is made of a metal member such as stainless steel, steel, or an aluminum alloy, but its thickness is sufficiently thinner than that of the partition wall member 45.

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

The cap member 47 is housed in the partition member 45 by being inserted into the above-mentioned opening end of the partition member 45, and more specifically, the cap member 47 is press-fitted or loosely fitted into the partition member 45. Here, the loose fitting means that the cap member 47 fitted in the partition wall member 45 is in a state of having a predetermined clearance with the partition wall member 45, and in the present embodiment, this loose fitting means. The cap member 47 is assembled to the partition member 45 by fitting.

The peripheral plate portion 47b of the cap member 47 is provided with a plurality of gas passage holes 47c 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 at the time of combustion of the second gas generating agent 52, and are peripheral. 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 is inserted with respect to the bottom plate portion 11. It is fixed by being joined. As a result, the second igniter assembly 40, which is integrated by assembling the second igniter 42, the partition portion 44, and the like in advance to the second holder 41, is fixed to the lower shell 10. become.

Therefore, the second holder 41 is configured to be positioned so as to project from the bottom plate portion 11 toward the space inside the housing, and in particular, the second combustion provided inside the second igniter assembly 40. The chamber SA2 will be arranged in the space inside the housing. Here, electron beam welding, laser welding, friction welding and the like can be preferably used for joining the bottom plate portion 11 and the second holder 41.

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

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 toward the outside of the housing, and the male connector described above is inserted into the second female connector portion to electrically connect the core wire of the harness and the terminal pin 42c. Continuity will be realized.

As shown in FIGS. 1 and 2, a filter 70 is housed in the space inside the housing 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 so 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 space inside the filter 70. Is located in. As a result, the first combustion chamber SA1 in which the first gas generating agent 51 is housed is formed in the space inside the filter 70 and in the space outside the partition portion 44. The filter 70 is arranged at a predetermined distance from the peripheral wall portion of the housing, whereby a gas discharge chamber SB is formed between the peripheral wall portion of the housing and the filter 70.

As the filter 70, for example, a filter 70 obtained by winding and sintering a metal wire such as stainless steel or steel, or a filter 70 obtained by pressing a net material woven with a metal wire and compacting the filter 70 can be used. As the net material, specifically, a knitted wire net, a plain woven wire net, an aggregate of crimp woven metal wires, and the like can be used.

Further, as the filter 70, a filter 70 obtained by winding a perforated metal plate or the like can also be used. In this case, as the perforated metal plate, for example, an expanded metal in which a staggered cut is made in the metal plate and the cut is expanded to form a hole and processed into a mesh shape, or a hole is made in the metal plate and at that time. Hook metal or the like that flattens the burrs generated on the periphery of the hole by crushing them is used. In this case, the size and shape of the holes to be formed can be appropriately 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 preferably used, and a non-ferrous metal plate such as aluminum, copper, titanium, nickel or an alloy thereof can also be used.

The filter 70 functions as a cooling means for cooling the gas by taking away the high-temperature heat of the gas when the gas generated in the first combustion chamber SA1 and the second combustion chamber SA2 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 with the central axis of the peripheral wall portion of the housing, and the central axis of the second igniter assembly 40 is also the peripheral wall of the housing. It is eccentric so that it does not overlap with the central axis of the part. With such a configuration, it is possible to prevent a dead space from being generated inside the housing, and the disc type gas generator 1A can be configured to be compact as a whole.

The first gas generating agent 51 is housed in the first combustion chamber SA1. The first gas generating agent 51 is a chemical that is ignited by heat particles generated by the operation of the first igniter 32 and generates gas by burning, and is located around the first igniter assembly 30. ing.

More specifically, the first gas generating agent 51 is a space inside the filter 70 and adjacent to the top wall portion 34a and the side wall portion 34b of the cup body 34A of the first igniter assembly 30, and the space. , It is arranged in 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 37 of the first igniter assembly 30 is arranged in the first combustion chamber SA1, the portion where the barrier portion 37a of the combustion control member 37 is located is not included. The side wall portion 34b of the cup body 34A does not directly face the first gas generating agent 51, and the barrier portion 37a is interposed between them.

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, and generally, these first gas generating agents are used as a molded product containing a fuel, an oxidizing agent and an additive. 51 and the second gas generating agent 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, for example, 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, nitrates containing cations selected from ammonia, etc. are used. As the nitrate, for example, sodium nitrate, potassium nitrate and the like are preferably used.

Examples of the additive include a binder, a slag forming agent, a combustion adjusting agent, and the like. As the binder, for example, an organic binder such as polyvinyl alcohol, a metal salt of carboxymethyl cellulose, a stearate, or an inorganic binder such as synthetic hydrotalcite or acidic clay can be preferably used. In addition, as binders, polysaccharide derivatives such as hydroxyethyl cellulose, hydroxypropyl methyl cellulose, cellulose acetate, cellulose propionate, butyrate acetate cellulose, nitrocellulose, microcrystalline cellulose, guagam, polyvinylpyrrolidone, polyacrylamide, and starch In addition, inorganic binders such as molybdenum disulfide, talc, bentonite, caustic soil, kaolin and alumina can also be preferably used. As the slag forming agent, silicon nitride, silica, acidic white clay and the like can be preferably used. As the combustion modifier, metal oxides, ferrosilicon, activated carbon, graphite and the like can be preferably used.

There are various shapes of the molded body of the gas generating agent, such as granular ones such as granular ones, pellet ones, and cylindrical ones, and disc ones. Further, in the columnar shape, a perforated (for example, single-hole cylinder shape, perforated cylinder shape, etc.) molded body having through holes inside the molded body is also used. These shapes are preferably selected as appropriate according to the specifications of the airbag device in which the disc-type gas generator 1A is incorporated. For example, a shape in which the gas generation rate changes with time during combustion of the gas generator. It is preferable to select the optimum shape according to the specifications, such as selection. In addition to the shape of the gas generating agent, it is preferable to appropriately select the size and filling amount of the molded product in consideration of the linear combustion rate of the gas generating agent, the pressure index, and the like.

Here, the first gas generating agent 51 and the second gas generating agent 52 may have the same composition or may have different compositions. Further, 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.

A plurality of gas outlets 24 are provided on the peripheral wall portion 22 of the upper shell 20 of the portion facing the filter 70 so as to face the gas discharge chamber SB. More specifically, the plurality of gas outlets 24 are provided in a row of dots along the circumferential direction of the peripheral wall portion 22 of the upper shell 20 at intervals from each other so as to surround the space inside the housing. Is located in. The plurality of gas outlets 24 are for leading the gas that has passed through the filter 70 to the outside of the housing via the gas discharge chamber SB.

Further, a metal sealing tape 25 as a sealing member is attached 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 sealing tape 25, an aluminum foil or the like having an adhesive member coated on one side can be preferably used, and the sealing 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 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 arranged so as to cover the boundary portion between the filter 70 and the bottom plate portion 11 so as to cover the filter 70 and the bottom plate portion 11. As a result, the lower support member 61 is located 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 the gas generated in the first combustion chamber SA1 and the second combustion chamber SA2 passes through the inside of the filter 70 during operation. It also functions as an outflow prevention means for preventing outflow from the gap between the lower end of the filter 70 and the bottom plate portion 11. The lower support member 61 is formed by, for example, pressing a metal plate-shaped member, and is preferably made of a steel plate such as ordinary steel or special steel (for example, a cold-rolled steel plate or a stainless steel plate). It is composed of members.

An upper support member 62 is arranged at an end of the first combustion chamber SA1 located on the top plate portion 21 side. The upper support member 62 has a substantially disk-like shape, and is arranged so as to cover the boundary portion between the filter 70 and the top plate portion 21 so as to be addressed to the filter 70 and the top plate portion 21. As a result, the upper support member 62 is located 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 the gas generated in the first combustion chamber SA1 and the second combustion chamber SA2 does not pass through the inside of the filter 70 during operation. It also functions as an outflow prevention means for preventing outflow from the gap between the upper end of the filter 70 and the top plate portion 21. Similar to the lower support member 61 described above, the upper support member 62 is formed by, for example, pressing a metal plate-shaped member, and is preferably a steel plate such as ordinary steel or special steel (for example,). It is composed of members made of cold-rolled steel sheets, stainless steel sheets, etc.).

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

The cushion material 63 is provided for the purpose of preventing the first gas generating agent 51 made of a molded body from being crushed by vibration or the like, and is preferably a molded body of ceramic fiber, rock wool, or a foamed resin ( For example, it is composed of a member made of foamed silicone, expanded polypropylene, foamed polyethylene, urethane foam, etc.), chloroprene, rubber typified by EPDM, and the like. The cushion material 63 is burned down by the combustion of the first gas generating agent 51.

If some measures are required to prevent the second gas generating agent 52 from being crushed due to vibration, this can be realized by using a cushion material as in the case of the first gas generating agent 51. In that case, a disc-shaped cushion material is placed between the closed end located on the top plate portion 21 side of the partition portion 44 and the second gas generating agent 52, or an annular plate-shaped cushion material is provided. It can be either arranged between the upper surface of the second holder 41 of the portion 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 side by the cushion material, and when the latter configuration is adopted, the second gas is pressed by the cushion material. The generating agent 52 is pressed toward the top plate portion 21 side. In addition, both the former configuration and the latter configuration may be adopted. Here, as the cushioning material for pressing the second gas generating agent 52 described above, the same material as the cushioning 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 the operation of the disc type gas generator according to the present embodiment, and FIG. 6 is a schematic cross-sectional view taken along the VI-VI line shown in FIG. is there. Further, FIG. 7 is a schematic cross-sectional view showing a second stage of the operation of the disc type gas generator according to the present embodiment. Next, the operation of the disk-type gas generator 1A according to the present embodiment will be described with reference to FIGS. 5 to 7.

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

As shown in FIGS. 5 and 6, in the first stage in which the first igniter 32 is operated, the igniter filled in the ignition portion 32b of the first igniter 32 is ignited by being heated by the resistor. , The ignition part 32b bursts when the igniting agent burns. As a result, the gunpowder 36 housed inside the cup body 34A is ignited and burned.

When the fire-transmitting agent 36 burns, a large amount of heat particles are generated inside the fire-transmitting room 35, and the temperature and pressure of the fire-burning room 35 rise, so that the cup body 34A made of a fragile member bursts or melts. .. As the cup body 34A bursts or melts, the fire transmission chamber 35 leads to the first combustion chamber SA1, and a large amount of the above-mentioned heat particles 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 34A, a part of the side wall portion 34b is covered by the barrier portion 37a of the combustion control member 37, so that the top wall portion 34a and the side wall portion 34b Only the remaining part of the cup body 34A (that is, the portion of the cup body 34A exposed toward the first combustion chamber SA1 by the open portion 37b of the combustion control member 37) burst or melted and was covered by the barrier portion 37a. The portion remains without bursting or melting.

As a result, the flame generated by the burning of the flame-transmitting agent 36 is ejected toward the top plate 21 side of the upper shell 20 and the central axis side of the housing, as shown by the arrow AR1 in the figure. , It is prevented from spouting to the side where the barrier portion 37a is located when viewed from the fire transmission chamber 35. Therefore, among the first gas generating agents 51 located around the first igniter assembly 30, the first gas generating agent 51 located in a direction other than the direction in which the barrier portion 37a is located when viewed from the firebox 35 is used. It is ignited and starts burning.

Of the first gas generating agent 51 located around the first igniter assembly 30, the first gas generating agent 51 located on the barrier portion 37a side when viewed from the firebox 35 starts combustion first. Combustion is started at a delayed timing as the burning of the first gas generating agent 51 spreads.

A large amount of gas is generated in the first combustion chamber SA1 with the combustion of the first gas generating agent 51. The gas generated in the first combustion chamber SA1 passes through the inside of the filter 70, and at that time, heat is taken away by the filter 70 and cooled, and the slag contained in the gas is removed by the filter 70 to make the gas. It flows into the discharge chamber SB.

At this time, the sealing tape 25 that has closed the plurality of gas outlets 24 is cleaved due to the pressure increase inside the housing caused by the combustion of the first gas generating agent 51. As a result, the gas generated in the first combustion chamber SA1 is started to be ejected toward the outside of the housing through the plurality of gas outlets 24 (see arrow AR2).

On the other hand, in this first stage, the cover member 46 is pressed against the partition wall 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 wall member 45 on the top plate portion 21 side is closed by the first covering portion 46a of the cover member 46, and the outer peripheral surface of the portion of the partition wall member 45 near the top plate portion 21 is the first cover member 46. 2 The state in which the covering portion 46b is in close contact with the covering portion 46b is maintained.

As a result, in the first stage, the first combustion chamber SA1 and the second combustion chamber SA2 do not communicate with each other, and the first gas generating agent 52 becomes the second gas generating agent 52 for which combustion has not yet started. The influence of the combustion of 51 is eliminated.

Next, at a timing delayed by a predetermined time from the operation of the first igniter 32 described above, the second igniter 42 operates by receiving the energization from the control unit described above.

As shown in FIG. 7, in the second stage in which the second igniter 42 is operated, the igniter filled in the ignition portion 42b of the second igniter 42 is ignited by being heated by the resistor, and the point is ignited. The ignition unit 42b bursts when the explosive burns. As a result, the second gas generating agent 52 housed in the second combustion chamber SA2 is sequentially ignited and combustion is started.

Here, prior to the start of combustion of the second gas generator 52, the first gas generator 51 was ignited in advance and burned, so that the disk type gas generator 1A as a whole was already heated to a high temperature. Since it is in the state, the combustion of the second gas generating agent 52 can be started smoothly without providing the ignition agent between the ignition unit 42b and the second gas generating agent 52, and the second gas generating agent 52 is generated. Combustion of the agent 52 is less likely to be interrupted.

At this time, due to the pressure increase in the second combustion chamber SA2 caused by the combustion of the second gas generating agent 52, pressure is applied to the cap member 47 housed in the second combustion chamber SA2. The pressure acts mainly on the top plate portion 47a of the cap member 47 in the direction along the axial direction of the housing, and on the peripheral plate portion 47b of the cap member 47 mainly in the direction 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 side of the upper shell 20, and the peripheral plate portion 47b is deformed so as to expand outward in the radial direction. Become. Therefore, the cap member 47 moves toward the top plate portion 21 side while the portion near the lower end of the peripheral plate portion 47b is in close contact with the inner peripheral surface of the partition wall 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.

With the above-mentioned movement of the cap member 47, 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 on the top plate portion 21 side of the partition wall member 45. Therefore, when the cover member 46 is separated from the partition wall 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 wall member 45 in the first combustion chamber SA1. Exposed to face.

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

As a result, as shown by the arrow AR3 in the figure, 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, so that the first combustion chamber SA1 Will be introduced to.

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, and at that time, heat is taken away by the filter 70 to be cooled, and the gas is contained in the gas. The slag contained therein is removed by the filter 70 and flows into the gas discharge chamber SB, and then is ejected to the outside of the housing through the plurality of gas outlets 24 (see arrow AR2).

In the first and second steps described above, the gas ejected from the plurality of gas outlets 24 to the outside of the disc-type gas generator 1A is the air provided adjacent to the disc-type gas generator 1A. Introduced inside the bag to inflate and deploy the airbag.

Here, the disc-type gas generator 1A according to the present embodiment is less susceptible to the influence of the ambient environment in which the disc-type gas generator 1A is placed (particularly the influence of the above-mentioned environmental temperature) during operation. The opening pressure of the plurality of gas outlets 24 provided in the housing (that is, the opening pressure of the sealing tape 25 at the portion that closes each of the plurality of gas outlets 24) so that a stable gas output can be obtained in the above. ) Is adjusted, and it is configured to be opened in multiple stages according to the internal pressure of the first combustion chamber SA1.

On the other hand, even when the plurality of gas outlets 24 are configured to be opened in multiple stages, each of the plurality of gas outlets 24 is preset in order to surely obtain a stable gas output. It is indispensable to open the gas accurately with the opening pressure, and the disk-type gas generator 1A according to the present embodiment has been improved in this respect as compared with the conventional case. The details will be described below with reference to a comparative example.

FIG. 8A is a conceptual diagram showing a configuration example of a gas outlet in the disc-type gas generator according to the comparative example, and FIG. 8B is a conceptual diagram showing the disk-type gas generator according to the present embodiment. It is a conceptual diagram which shows the structural example of a gas outlet. Here, in FIGS. 8A and 8B, the gas outlet in which the opening pressure is set to be relatively low by adjusting the opening area to be large is represented by reference numeral 24a, and the opening area is represented by reference numeral 24a. The gas outlet whose opening pressure is set to be relatively high by being adjusted to be small is represented by reference numeral 24b.

In the disk-type gas generator 1A'according to the comparative example shown in FIG. 8 (A), the first gas generating agent in the portion that directly receives the flame from the fire transmission chamber of the first igniter assembly 30 and ignites. As seen from the above, a part of the gas outlets provided in the portion directly facing the filter 70 is set as the gas outlet 24a whose opening pressure is set to be relatively low, and the other gas outlets. (Seen from the first gas generating agent in the portion that directly receives and ignites the flame from the fire transmission chamber of the first igniter assembly 30, it is blocked by the combustion control member 37 and the second igniter assembly 40. (Including the partial gas outlet) is a gas outlet 24b whose opening pressure is set to be relatively high.

In the case of such a configuration, the gas outlet 24a whose opening pressure is set to be relatively low may have the gas flow velocity locally extremely increased in the vicinity of the gas outlet 24a. If the temperature rises extremely locally in the vicinity of the gas outlet 24a, or both of them occur, the gas may be released by a pressure lower than the set opening pressure. Therefore, when this configuration is adopted, there is a possibility that the desired gas output cannot be obtained because the internal pressure of the first combustion chamber SA1 does not rise sufficiently, especially in a low temperature environment.

On the other hand, in the disk-type gas generator 1A according to the present embodiment shown in FIG. 8B, the first portion of the portion that directly receives the flame from the fire transmission chamber of the first igniter assembly 30 and ignites. The gas outlet provided in the portion directly facing the gas generating agent via the filter 70 is a gas outlet 24b whose opening pressure is set to be relatively high, and the first igniter assembly 30 The gas outlet of the part blocked by the combustion control member 37 and the second igniter assembly 40 is opened when viewed from the first gas generating agent of the part that directly receives the flame from the fire transmission chamber and ignites. The gas outlet 24a is set so that the pressure is relatively low.

In the case of such a configuration, the gas outlet 24a whose opening pressure is set to be relatively low may have the gas flow velocity locally extremely increased in the vicinity of the gas outlet 24a. Since the temperature does not rise extremely locally in the vicinity of the gas outlet 24a or both of them occur, there is a possibility that the gas will be released by a pressure lower than the set opening pressure. It disappears. On the other hand, in the gas outlet 24b whose opening pressure is set to be relatively high, the flow velocity of the gas locally becomes extremely high in the vicinity of the gas outlet 24b, or in the vicinity of the gas outlet 24b. Although there is a risk that the temperature will rise extremely locally or both of these will occur, the opening pressure is set relatively high in the first place, so it is almost unaffected by it. It will be released at the set opening pressure.

Therefore, in the disk type gas generator 1A according to the present embodiment, as described above, it is located on the side opposite to the central axis side of the housing when viewed from the fire transmission room 35 among the plurality of gas outlets 24. The open pressure of the gas outlet (that is, the gas outlet indicated by reference numeral 24a in the figure) blocked by the second igniter assembly 40 as viewed from the gas outlet and the fire transmission room 35 is the other gas outlet (that is, the gas outlet (the gas outlet indicated by reference numeral 24a in the figure). That is, since the pressure is set lower than the opening pressure of the gas outlet (reference numeral 24b) in the figure, the gas outlet 24 is opened in multiple stages in a state closer to the set value. Therefore, by adopting this configuration, it becomes possible to make it less susceptible to the influence of the surrounding environment, and it becomes possible to obtain a more stable gas output.

In addition, the present inventor actually prototyped the disc-type gas generator 1A'according to the comparative example and the disc-type gas generator 1A according to the present embodiment, and what kind of opening pressure is applied to the gas outlet. It was confirmed by experiment whether the difference would occur. Here, the opening pressure of the gas outlet 24a whose opening pressure is set to be relatively low is set to 7.2 [MPa], and the opening pressure of the gas outlet 24b whose opening pressure is set to be relatively high is set to 7.2 [MPa]. The opening pressure was set to 10 [MPa] as a set value.

As a result, in the disk type gas generator 1A'according to the comparative example, the measured value of the opening pressure of the gas outlet 24a whose opening pressure was set to 7.2 [MPa] was 6.8 on average. The measured value of the opening pressure of the gas outlet 24b set to [MPa] and the opening pressure set to 10 [MPa] is 8.2 [MPa] on average, and the disk according to the present embodiment. In the type gas generator 1A, the measured value of the opening pressure of the gas outlet 24a whose opening pressure is set to 7.2 [MPa] is 7.6 [MPa] on average, and the opening pressure becomes 7.6 [MPa]. The measured value of the open pressure of the gas outlet 24b set to 10 [MPa] in the set value became 8.8 [MPa] on average.

That is, by using the disc-type gas generator 1A according to the present embodiment, the gas outlet 24 has multiple stages in a state closer to the set value than in the case of using the disc-type gas generator 1A'according to the comparative example. It was also experimentally confirmed that the gas was released.

FIG. 9 is a perspective view of the combustion control member according to the first to sixth modified examples. Hereinafter, with reference to FIG. 9, some of the assumed modifications of the combustion control member in the disc type gas generator 1A according to the present embodiment will be described.

The combustion control member 37A according to the first modification shown in FIG. 9A sets the opening angle of the opening portion 37b in the circumferential direction of the combustion control member 37A to about 180 °, and the upper end thereof is the combustion control member 37A. It is configured to reach the upper end opening of.

The combustion control member 37B according to the second modification shown in FIG. 9B gradually increases the opening angle of the opening portion 37b in the circumferential direction of the combustion control member 37B from the lower end to the upper end, and is about 120 at the lower end. The temperature is set to about 180 ° at the upper end, and the upper end thereof reaches the upper end opening of the combustion control member 37B.

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

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

The combustion control member 37E according to the fifth modification shown in FIG. 9 (E) is arranged so that two open portions 37b are lined up in the circumferential direction of the combustion control member 37E, and the opening angles of the respective open portions 37b are set. The temperature is set to about 60 °, and these two open portions 37b are formed in a window shape on the barrier portion 37a, respectively.

In the combustion control member 37F according to the sixth modification shown in FIG. 9F, the barrier portion 37a is formed in a substantially cylindrical shape with a bottom, and the opening angle of the opening portion 37b in the circumferential direction of the combustion control member 37F is about 120. The temperature is set to °, and the open portion 37b is formed in a window shape on the barrier portion 37a.

Even when the combustion control members 37A to 37F according to the first to sixth modifications are used, the same effect as when the combustion control members 37 according to the above-described embodiment can be obtained.

(Embodiment 2)
FIG. 10 is a schematic view of the disc type gas generator according to the second embodiment, and FIG. 11 is a perspective view of the cup body shown in FIG. Further, FIG. 12 is a conceptual diagram showing a configuration example of a gas outlet in the disc-type gas generator shown according to the present embodiment. Hereinafter, the disc type gas generator 1B according to the present embodiment will be described with reference to FIGS. 10 to 12. The disc-type gas generator 1B according to the present embodiment also has a so-called dual structure like the disc-type gas generator 1A according to the above-described first embodiment.

As shown in FIGS. 10 and 11, the disc-type gas generator 1B according to the present embodiment is a combustion control member 37 (FIG. 10) when compared with the disc-type gas generator 1A according to the above-described first embodiment. The point that the cup body 34A (see FIG. 1 etc.) is not provided, the cup body 34B having a configuration different from that of the above-mentioned cup body 34A (see FIG. 1 etc.) is provided, and the structure for assembling the cup body 34B to the bottom plate portion 11. The composition is mainly different in that they are different.

Specifically, the cup body 34B has a cup-like shape with an open end on the bottom plate portion 11 side, and has a top wall portion 34a, a side wall portion 34b, and a flange portion 34c. Unlike the cup body 34A described above, the cup body 34B is made of a non-fragile member that does not burst or melt even when the fire-transmitting agent 36 is burned, and is made of a metal member such as stainless steel or steel.

A plurality of communication holes 34d are provided at predetermined positions of the side wall portion 34b of the cup body 34B. The plurality of communication holes 34d are for ejecting a flame generated at the time of combustion of the flame transmitting agent 36 toward the first combustion chamber SA1, and the side wall portion 34b is provided along the thickness direction of the side wall portion 34b. It is provided to penetrate. That is, the plurality of communication holes 34d correspond to a combustion control mechanism that controls the spread of the first gas generating agent 51 that is ignited by the combustion of the propellant 36.

Here, the plurality of communication holes 34d are all provided in the portion of the cup body 34B located closer to the central axis of the housing, and the portion of the cup body 34B located closer to the central axis of the housing. It is not provided on the opposite side. In FIG. 11, the direction in which the central axis of the housing is located when viewed from the cup body 34B is indicated by the arrow A.

A metal sealing tape 34e as a sealing member is attached to the inner peripheral surface of the side wall portion 34b of the cup body 34B so as to close the plurality of communication holes 34d. As the seal tape 34e, an aluminum foil or the like coated with an adhesive member on one side can be preferably used, and the seal tape 34e allows the fire-transmitting agent 36 to have a plurality of communication holes when the disc type gas generator 1A is not operating. It is prevented from leaking to the first combustion chamber SA1 via 34d.

The cup body 34B is assembled to the first holder 31 so that the fire transmission chamber 35 formed inside the cup body 34B faces the ignition portion 32b of the first igniter 32. More specifically, the flange portion 34c The crimped portion 31e provided on the first holder 31 is bent and fixed to the first holder 31 in a state of being fixed to the upper surface of the first holder 31.

In the disk-type gas generator 1B configured in this way, the cup body 34B bursts even when the fire-transmitting agent 36 housed in the fire-box 35 burns in the first stage when the first igniter 32 operates. Alternatively, it does not melt, and as the temperature and pressure of the firebox 35 increase, the sealing tape 34e at the portion that closes the plurality of communication holes 34d is cleaved.

As a result, the flame generated by the combustion of the explosive charge 36 is ejected toward the central axis side of the housing. Therefore, among the first gas generating agents 51 located around the first igniter assembly 30, the first gas generating agent 51 arranged on the side where the plurality of communication holes 34d are located as viewed from the fire transmission chamber 35 is , It will be ignited by the flame and start burning.

Here, as shown in FIG. 12, also in the disk-type gas generator 1B according to the present embodiment, the first igniter assembly 30 is similar to the disk-type gas generator 1A according to the above-described first embodiment. The opening pressure is relative to the gas outlet provided in the part directly facing the first gas generating agent in the part that directly receives the flame from the fire transmission chamber and ignites. The gas outlet 24b is set high, and the first igniter set is viewed from the first gas generator of the part that directly receives the flame from the fire transmission chamber of the first igniter assembly 30 and ignites. The gas outlet of the portion blocked by the solid body 30 and the second igniter assembly 40 is a gas outlet 24a whose opening pressure is set to be relatively low.

Therefore, even when the disc-type gas generator 1B according to the present embodiment is used, the same effect as that described in the above-described first embodiment can be obtained, and the gas outlet is in a state closer to the set value. Since the 24 is opened in multiple stages, it is possible to make it less susceptible to the influence of the surrounding environment, and it is possible to obtain a more stable gas output.

FIG. 13 is a perspective view of the cup body according to the seventh to ninth modified examples. Hereinafter, with reference to FIG. 13, some of the assumed modifications of the cup body in the disc type gas generator 1B according to the present embodiment will be described.

The cup body 34B1 according to the seventh modification shown in FIG. 13 (A) is a straight line along the axial direction of the cup body 34B1 at a predetermined position of the side wall portion 34b of the cup body 34B1 instead of the communication hole 34d described above. A score 34f extending in a shape is formed. The score 34f is formed by making the thickness of the side wall portion 34b extremely thinner than that of the other portions, and when the fire-transmitting agent 36 is burned, the cup body 34B1 breaks from the score 34f as a starting point. That is, the score 34f corresponds to a combustion control mechanism that controls the spread of the first gas generating agent 51 that is ignited by the combustion of the propellant 36. It is not necessary to provide the above-mentioned sealing tape 34e on the cup body 34B1.

The cup body 34B2 according to the eighth modification shown in FIG. 13B is provided with a score 34f having a shape different from that of the cup body 34B1 described above, and has a substantially H-shaped plan view at a predetermined position on the side wall portion 34b. A score 34f is provided in the shape of the shape.

The cup body 34B3 according to the ninth modification shown in FIG. 13C is provided with scores 34f having different shapes at positions different from those of the cup body 34B1 described above, and is provided at predetermined positions on the top wall portion 34a. A score 34f having three straight portions extending so as to intersect is provided. The score 34f extends radially from the central portion of the top wall portion 34a in a predetermined direction.

Even when the cup bodies 34B1 to 34B3 according to the 7th to 9th modifications are used, substantially the same effect as the case where the cup bodies 34B according to the above-described embodiment can be obtained.

(Embodiment 3)
FIG. 14 is a schematic view of the disc type gas generator according to the third embodiment. Further, FIG. 15 is a conceptual diagram showing a configuration example of a gas outlet in the disc-type gas generator according to the present embodiment. Hereinafter, the disc-type gas generator 1C according to the present embodiment will be described with reference to FIGS. 14 and 15. The disc-type gas generator 1C according to the present embodiment has a so-called single structure, unlike the disc-type gas generator 1A according to the above-described first embodiment.

As shown in FIG. 14, the disc-type gas generator 1C according to the present embodiment has a second igniter assembly 40 (FIG. 14) when compared with the disc-type gas generator 1A according to the above-described first embodiment. The configuration is mainly different in that it does not have (see 1st class). Along with this, the space inside the housing and the space inside the filter 70 is defined as the combustion chamber SA in which the first gas generating agent 51 is housed.

The first igniter assembly 30 is eccentrically arranged so that its central axis does not overlap with the central axis of the peripheral wall portion of the housing, and the first gas generating agent 51 is located around the first igniter assembly 30. doing. The cup body 34A and the combustion control member 37 have the same configurations as the cup body 34A and the combustion control member 37 (see FIG. 1 and the like) in the above-described first embodiment, and the axial direction thereof is the axial direction of the housing. It is arranged inside the combustion chamber SA so as to be parallel to.

The barrier portion 37a of the combustion control member 37 is a portion of the top wall portion 34a and the side wall portion 34b of the cup body 34A that defines the firebox 35, which is located on the side opposite to the portion located near the central axis of the housing. It is located so as to directly cover the side wall portion 34b, and the open portion 37b of the combustion control member 37 exposes the top wall portion 34a and the side wall portion 34b of the portion located near the central axis of the housing. positioned.

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

With this configuration, when the explosive charge 36 is burned, the portion exposed by the open portion 37b of the top wall portion 34a and the side wall portion 34b of the cup body 34A bursts due to the combustion of the explosive charge 36. Alternatively, it will melt, and the flame generated by the combustion of the explosive charge 36 will be ejected into the combustion chamber SA in a predetermined direction (that is, toward the central axis side of the housing).

Here, as shown in FIG. 15, in the disk-type gas generator 1C according to the present embodiment, the portion of the first igniter assembly 30 that directly receives the flame from the fire transmission room and ignites. 1 The gas outlet provided in the portion directly facing the gas generator via the filter 70 is the gas outlet 24b whose opening pressure is set to be relatively high, and the first igniter assembly The opening pressure of the gas outlet of the portion blocked by the combustion control member 37 is set to be relatively high when viewed from the first gas generating agent of the portion that directly receives the flame from the fire transmission room of 30 and ignites. The gas outlet 24a is set.

With this configuration, the gas outlet 24a whose opening pressure is set to be relatively low may have the gas flow velocity locally extremely increased in the vicinity of the gas outlet 24a, or the gas. Since the temperature does not rise extremely locally in the vicinity of the spout 24a or both of them occur, there is a risk that the gas will be released by a pressure lower than the set opening pressure. It disappears. On the other hand, in the gas outlet 24b whose opening pressure is set to be relatively high, the flow velocity of the gas locally becomes extremely high in the vicinity of the gas outlet 24b, or in the vicinity of the gas outlet 24b. Although there is a risk that the temperature will rise extremely locally or both of these will occur, the opening pressure is set relatively high in the first place, so it is almost unaffected by it. It will be released at the set opening pressure.

Therefore, in the disc type gas generator 1C according to the present embodiment, as described above, it is located on the side opposite to the central axis side of the housing when viewed from the firebox 35 among the plurality of gas outlets 24. The opening pressure of the gas outlet (that is, the gas outlet indicated by reference numeral 24a in the figure) is set lower than the opening pressure of another gas outlet (that is, the gas outlet indicated by reference numeral 24b in the figure). As a result, the gas outlet 24 is opened in multiple stages in a state closer to the set value. Therefore, by adopting this configuration, it becomes possible to make it less susceptible to the influence of the surrounding environment, and it becomes possible to obtain a more stable gas output.

(Other forms, etc.)
In the above-described first to third embodiments of the present invention and modifications thereof, a case where the opening areas of the plurality of gas outlets are different from each other is exemplified as a method of adjusting the opening pressures of the plurality of gas outlets. Although it was explained in the above, it is also possible to adjust this by other methods. That is, since the opening pressure of the gas outlet is mainly determined by the opening area and peripheral length of the gas outlet, the material and thickness of the sealing tape that closes the gas outlet, and the like, any or some of these are used. It should be different from each other.

Further, in the above-described first and second embodiments of the present invention and modifications thereof, the first igniter and the second igniter are energized at different timings so that the second igniter operates the first igniter. The case where it is configured to operate at a timing delayed from the timing of is described as an example, but even if it is configured to operate at the same timing by being energized at the same timing. Good. Further, even when the first igniter and the second igniter are energized at the same timing, the second igniter is provided by providing a delaying agent for delaying the ignition of the igniter in the ignition portion of the second igniter. The time required from energization to ignition of the igniting agent is extended, so that the first igniter and the second igniter are energized at the same timing, and the timing of the start of combustion of the second gas generating agent is set to the first. It may be configured so as to be delayed from the timing of starting combustion of the gas generating agent.

Further, in the above-described first and second embodiments of the present invention and modified examples thereof, 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. 2 Regarding the combustion chamber, this may be used as a fire transmission chamber, and the fire transmission chamber may be filled with a fire transmission agent. In this configuration, the second igniter is activated to burn the igniter, and the combustion of the igniter generates a large amount of heat particles inside the firebox and the transfer. The pressure in the firebox 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, so that the above-mentioned large amount of heat particles are released. 1 Flows into the combustion chamber. Therefore, when this configuration is adopted, the combustion of the first gas generating agent can be promoted by the explosive charge filled inside the partition portion composed of the partition wall member, the cup member, and the cap member.

Further, in the above-described first to third embodiments of the present invention and modified examples thereof, a case where the igniter is configured to be assembled to the bottom plate portion of the housing via a metal holder has been illustrated and described. However, the igniter may be configured to be assembled to the bottom plate portion of the housing by so-called insert molding.

Furthermore, the characteristic configurations shown in the above-described embodiments 1 to 3 of the present invention and variations thereof can be combined with each other as long as the gist of the present invention is not deviated.

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

1A to 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, 22 peripheral wall, 23 flange , 24, 24a, 24b gas outlet, 25 sealing tape, 30 first igniter assembly, 31 first holder, 31a upper recess, 31b lower recess, 31c through hole, 31d, 31e caulking part, 32 first Ignizer, 32a base, 32b ignition part, 32c terminal pin, 33 first seal member, 34A, 34B, 34B1 to 34B3 cup body, 34a top wall part, 34b side wall part, 34c flange part, 34d communication hole, 34e seal tape , 34f score, 35 fire chamber, 36 fire agent, 37, 37A to 37F combustion control member, 37a barrier part, 37b open part, 37c fixed part, 37d holding part, 40 second igniter assembly, 41 second Holder, 41a upper recess, 41b lower recess, 41c through hole, 41d caulking part, 42 second igniter, 42a base, 42b ignition part, 42c terminal pin, 43 second seal member, 44 partition, 45 partition member, 45a 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 generator, 52 second gas Generator, 61 Lower support member, 62 Upper support member, 63 Cushion material, 70 Filter, SA combustion chamber, SA1 1st combustion chamber, SA2 2nd combustion chamber, SB gas discharge chamber.

Claims (3)

Includes a substantially cylindrical peripheral wall portion provided with a plurality of gas outlets, a top plate portion that closes one end of the peripheral wall portion in the axial direction, and a bottom plate portion that closes the other end of the peripheral wall portion in the axial direction. A housing with a combustion chamber inside that contains 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 contains an igniter that ignites during operation.
A cup body that defines a firebox in which the explosive is housed and is arranged so as to project toward the combustion chamber so that the firebox faces the ignition portion.
A combustion control mechanism for controlling the spread of the gas generating agent ignited by the combustion of the explosive is provided.
The plurality of gas outlets are located at intervals from each other along the circumferential direction of the peripheral wall portion.
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 combustion control mechanism provides directivity so that a flame generated by burning the explosive is ejected from the firebox toward the central axis side of the peripheral wall portion.
The opening pressure of the gas outlet located on the side opposite to the central axis side of the peripheral wall portion when viewed from the firebox among the plurality of gas outlets is the other gas among the plurality of gas outlets. A gas generator that is set lower than the open pressure of the spout. The cup body has a top wall portion and a side wall portion that define the firebox, and is composed of a fragile member that bursts or melts due to the combustion of the explosive as the operation of the igniter.
The combustion control mechanism is arranged in the combustion chamber, and is composed of a combustion control member made of a non-fragile member that does not burst or melt even when the explosive is burned.
The combustion control member exposes at least a part of the side wall portion located near the central axis of the peripheral wall portion, and the portion of the side wall portion located near the central axis of the peripheral wall portion. The gas generator according to claim 1, wherein the gas generator has a shape that directly covers a portion located on the opposite side without interposing the gas generator. The gas generator according to claim 1, wherein the combustion control mechanism is composed of a communication hole or a score provided in a portion of the cup body located near the central axis of the peripheral wall portion.

Images