JP7428600B2 - gas generator - Google Patents

Description

The present invention relates to a gas generator.

Conventionally, a gas generator has an igniter and a gas generating agent arranged in a housing, and when the igniter is operated, the gas generating agent is combusted, and the combustion gas is discharged to the outside from a gas exhaust hole formed in the housing. is widely used.

In this regard, gas generators are known in which a cylindrical filter is disposed between a combustion chamber and a gas discharge hole in order to cool combustion gas and collect residue (for example, Patent Document 1). In such a gas generator, the housing includes a cylindrical peripheral wall, a top plate that closes one end of the peripheral wall, and a bottom plate that closes the other end and to which the igniter is fixed. The filter is widely used, and one end surface of the filter is supported by contacting the top plate part, and the other end surface thereof is supported by contacting the bottom plate part.

By the way, in a gas generator, the internal pressure of the housing increases due to the generation of combustion gas, and the housing may deform so as to expand. At this time, when the top plate and the bottom plate are connected only by the cylindrical peripheral wall, as in the above-mentioned gas generator, due to the structure, the top plate and the bottom plate are connected more than the peripheral wall. It tends to deform more easily.

On the other hand, in the gas generator disclosed in Patent Document 1, a part of the igniter collar for attaching the igniter to the bottom plate of the housing is formed thinly, and the igniter collar is changed in response to the deformation of the bottom plate. By deforming the bottom plate, it is configured to absorb the distortion caused by the deformation of the bottom plate portion. This suppresses the formation of a gap between the igniter collar and the housing and the formation of cracks in the housing, thereby suppressing combustion gas from leaking to the outside of the housing through the gap or the crack.

Japanese Patent Application Publication No. 2008-114718 US Patent Application Publication No. 2016/52485

However, in the above-described gas generator, it has not been possible to sufficiently prevent the top plate portion and the bottom plate portion from separating from the end face of the filter due to deformation of the housing due to the pressure of the combustion gas. If the top plate or bottom plate separates from the end face of the filter and a gap is created between the end face of the filter and the top plate or between the end face of the filter and the bottom plate, part of the combustion gas may not pass through the filter. There is a risk that a so-called "short path" in which the gas passes through the gap, reaches the gas discharge hole, and is discharged from the housing occurs.

The technology of the present disclosure has been made in view of the above-mentioned problems, and its purpose is to provide a technology that can suppress short paths in a gas generator.

In order to solve the above problems, the technology of the present disclosure employs the following configuration. That is, the technology of the present disclosure includes: an ignition section; a combustion chamber in which a gas generating agent that is combusted by the operation of the ignition section is disposed;
a cylindrical peripheral wall; a first wall provided at one end of the peripheral wall; and a first wall provided at the other end of the peripheral wall to face the first wall; a second wall part that defines the combustion chamber together with a first wall part and to which the ignition part is fixed, the housing having a gas discharge hole that communicates the combustion chamber with the outside of the housing. A gas generator comprising: a housing; and a cylindrical filter disposed in the combustion chamber so as to surround the gas generating agent and with the gas discharge hole located outside the gas generator, The peripheral wall portion is formed on the circumference of the peripheral wall portion at a predetermined height from the second wall portion, and the height of the peripheral wall portion is increased due to an increase in pressure within the combustion chamber caused by activation of the ignition portion. The filter has a deformed portion that deforms to become such that one end thereof is in contact with the first wall portion, and the other end is located on the first wall side with respect to the deformed portion, A gas generator disposed within the housing.

In other words, the gas generator of the present disclosure is configured such that the deformable portion deforms so that the height of the peripheral wall portion increases due to an increase in pressure within the combustion chamber, and the volume of the housing increases. Therefore, the housing deforms so that the entire first wall portion is lifted relative to the second wall portion. Thereby, expansion of the housing is absorbed by the increase in volume of the housing due to deformation of the deformable portion, and deformation of the first wall portion and the second wall portion is suppressed. Furthermore, since the filter is arranged in the housing such that one end of the filter is in contact with the first wall and the other end is located on the first wall side with respect to the deformed part, the deformed part does not deform. When the height of the peripheral wall increases, the filter will rise together with the first wall. According to such a gas generator, even if the housing is deformed due to an increase in pressure within the combustion chamber, deformation of the first wall portion is suppressed and the filter is lifted together with the first wall portion, so that one end of the filter and The state of contact with the first wall portion is maintained. As a result, according to the gas generator of the present disclosure, it is possible to suppress a short pass caused by the first wall separating from one end of the filter. Note that the state of contact between the filter and the first wall portion may be a state in which they are in direct contact with each other, or a state in which they can be said to be in substantial contact with each other via a gasket or the like, i.e. It may be an indirect contact state.

Further, in the gas generator of the present disclosure, the deformed portion may be formed as a part of the peripheral wall portion, and further may have a wall thickness thinner than other portions of the peripheral wall portion, and , the circumferential wall may be bent in a cross section along the height direction.

According to this, by forming the deformable portion thinly, the deformable portion can be made easier to deform than other portions of the peripheral wall portion. Further, by forming the deformable portion by bending it, the deformable portion can be deformed so that the height of the peripheral wall portion becomes higher.

Further, in the gas generator of the present disclosure, the gas generator is press-fitted into an inner wall surface of the peripheral wall portion on the first wall side with the deformed portion as a reference, and is not fixed to the second wall portion. The filter may further include a holding member, wherein the other end of the filter is held by the holding member, and the one end of the filter is in contact with an inner wall surface of the first wall.

According to this, since the holding member is press-fitted into the inner wall surface of the peripheral wall part on the side closer to the first wall part than the deformable part and is not fixed to the second wall part, the deformable part deforms and the peripheral wall part When the height of the holding member increases, the holding member will be lifted together with the first wall portion. Therefore, even when the deformable portion deforms and the height of the peripheral wall portion increases, the state in which the other end of the filter is held by the holding member is maintained. As a result, according to the gas generator of the present disclosure, short passes caused by the holding member separating from the other end of the filter can also be suppressed.

Further, the gas generator of the present disclosure further includes a holding member that is supported by the deformed portion formed by bending inside the housing and is not fixed to the second wall portion, and the holding member is not fixed to the second wall portion, The other end may be held by the holding member, and the one end of the filter may be in contact with the inner wall surface of the first wall portion.

According to this, since the holding member is supported by the deformable part and is not fixed to the second wall part, when the deformable part deforms and the height of the peripheral wall part increases, the holding member is moved to the first wall part. It will be lifted up together with the department. Therefore, even when the deformable portion deforms and the height of the peripheral wall portion increases, the state in which the other end of the filter is held by the holding member is maintained. As a result, according to the gas generator of the present disclosure, short passes caused by the holding member separating from the other end of the filter can also be suppressed.

In the gas generator of the present disclosure, the peripheral wall further includes a protrusion protruding toward the combustion chamber from an inner wall surface of the peripheral wall on the first wall side with respect to the deformed part. The other end of the filter may be held by the protrusion, and the one end of the filter may be in contact with an inner wall surface of the first wall.

According to this, since the protrusion is formed on the first wall side with the deformed part as a reference, when the deformed part deforms and the height of the peripheral wall increases, the protrusion is formed along with the first wall. It will be lifted. Therefore, even when the deformable portion deforms and the height of the peripheral wall portion increases, the state in which the other end of the filter is held by the protrusion portion is maintained. As a result, according to the gas generator of the present disclosure, it is also possible to suppress short passes caused by the protrusion separating from the other end of the filter.

Further, in the gas generator of the present disclosure, the first wall portion has a peripheral portion connected to the peripheral wall portion and against which the one end of the filter comes into contact, and a central portion adjacent to the peripheral portion, In a cross section along the height direction of the peripheral wall part, the peripheral part may be inclined to intersect with each of the peripheral wall part and the central part at an obtuse angle.

Here, an obtuse angle refers to an angle that is larger than a right angle and smaller than a rectangular angle. According to the gas generator, the peripheral portion comes into contact with one end of the filter from the outside in the radial direction of the filter. As a result, one end of the filter is supported by the peripheral portion in contact with the radially outward load due to combustion of the gas generating agent. This prevents the filter from shifting due to a radially outward load acting on the filter due to combustion of the gas generating agent, and it is possible to maintain a state of contact between one end of the filter and the first wall portion. As a result, according to the gas generator of the present disclosure, short paths can be suppressed more suitably.

Further, in the gas generator of the present disclosure, the ignition unit includes a plurality of ignition devices, the plurality of ignition devices are fixed to the second wall portion, and corresponding to each of the plurality of ignition devices, A plurality of cylindrical inner cylinder members surrounding each ignition device may be attached along the height direction of the peripheral wall portion. The technology of the present disclosure can be applied to, for example, a so-called single-type gas generator that includes only one ignition device, and a so-called dual-type gas generator that includes two ignition devices.

According to the technology of the present disclosure, it is possible to suppress short paths in a gas generator.

1 is an axial cross-sectional view of a gas generator according to Embodiment 1. FIG. FIG. 3 is a perspective view of the lower shell according to the first embodiment. FIG. 3 is a diagram showing a state in which the gas generator according to Embodiment 1 is in operation. FIG. 3 is an axial cross-sectional view of a gas generator according to Modification 1 of Embodiment 1. FIG. 7 is a diagram showing a state in which the gas generator according to Modification 1 of Embodiment 1 is in operation. FIG. 3 is an axial cross-sectional view of a gas generator according to a second modification of the first embodiment. FIG. 7 is a diagram showing a state in which the gas generator according to Modification 2 of Embodiment 1 is in operation. FIG. 3 is an axial cross-sectional view of a gas generator according to a third modification of the first embodiment. FIG. 3 is an axial cross-sectional view of a gas generator according to a second embodiment.

A gas generator according to an embodiment of the present disclosure will be described below with reference to the drawings. Note that the configurations and combinations thereof in each embodiment are merely examples, and additions, omissions, substitutions, and other changes to the configurations can be made as appropriate without departing from the spirit of the present invention. This disclosure is not limited by the embodiments, but only by the claims.

<Embodiment 1>
FIG. 1 is an axial cross-sectional view of a gas generator 100 according to the first embodiment. In FIG. 1, the state of the gas generator 100 before operation is shown. The gas generator 100 is, for example, an airbag gas generator used for airbags.

[overall structure]
As shown in FIG. 1, the gas generator 100 includes a first ignition device 4X, a second ignition device 4Y, a first inner cylinder member 5X, a second inner cylinder member 5Y, a filter 6, and a retainer 7. , a transfer powder 110, a first gas generating agent 120X, a second gas generating agent 120Y, and a housing 1 that accommodates these. The gas generator 100 is configured as a so-called dual-type gas generator that includes two ignition devices. The configuration including the first ignition device 4X and the second ignition device 4Y corresponds to an "ignition section" according to the present disclosure. The gas generator 100 burns the first gas generating agent 120X by operating the first igniter 4X, and burns the second gas generating agent 120Y by operating the second igniter 4Y, thereby producing a relatively large amount of combustion gas. The gas discharge hole 11 is configured to discharge the gas from the gas discharge hole 11.

[housing]
The housing 1 has both ends in the axial direction closed by joining an upper shell 2 and a lower shell 3 made of metal, each formed in a substantially cylindrical shape with a bottom, with their open ends facing each other. It is formed into a short cylindrical shape. Here, the direction along the axial direction of the housing 1 is defined as the height direction (vertical direction) of the gas generator 100, the upper shell 2 side (that is, the upper side in FIG. 1) is the upper side of the gas generator 100, and the lower part The shell 3 side (ie, the lower side in FIG. 1) is the lower side of the gas generator 100.

The upper shell 2 has a cylindrical upper peripheral wall part 21 and a top plate part 22 that closes the upper end of the upper peripheral wall part 21, thereby forming an internal space. An opening in the upper shell 2 is formed by the lower end of the upper peripheral wall 21 . The lower shell 3 has a cylindrical lower peripheral wall part 31 and a bottom plate part 32 that closes the lower end of the lower peripheral wall part 31, thereby forming an internal space. A first ignition device 4X and a second ignition device 4Y are fixed to the bottom plate portion 32.

The housing 1 is formed by fitting the upper side peripheral wall part 21 of the upper shell 2 and the lower side peripheral wall part 31 of the lower shell 3. More specifically, the upper end portion of the lower peripheral wall portion 31 is press-fitted into the inner wall surface of the upper peripheral wall portion 21, and these are joined by laser welding or the like, thereby forming a short cylindrical shape with both axial ends closed. A housing 1 is formed. The upper peripheral wall part 21 of the upper shell 2 and the lower peripheral wall part 31 of the lower shell 3 form a cylindrical peripheral wall part 12 that connects the top plate part 22 and the bottom plate part 32. That is, the housing 1 includes a cylindrical peripheral wall 12, a top plate 22 provided at one end of the peripheral wall 12, and a bottom plate 32 provided at the other end. The top plate portion 22, the bottom plate portion 32, and the peripheral wall portion 12 define a first combustion chamber 10X in which the first gas generating agent 120X is placed. The top plate portion 22 corresponds to a “first wall portion” according to the present disclosure, and the bottom plate portion 32 corresponds to a “second wall portion” according to the present disclosure. Further, the first combustion chamber 10X corresponds to a "combustion chamber" according to the present disclosure. As shown in FIG. 1, in the upper peripheral wall portion 21 of the upper shell 2, a plurality of gas exhaust holes 11 are formed in line along the circumferential direction to communicate the first combustion chamber 10X with the external space of the housing 1. There is. The gas discharge hole 11 is closed with a seal tape (not shown) before the first ignition device 4X is activated.

Here, as shown in FIG. 1, the peripheral wall part 12 has a deformed part D1 formed on the circumference of the peripheral wall part 12 at a position at a predetermined height from the bottom plate part 32. The deformed portion D1 is formed as a part of the peripheral wall portion 12. More specifically, the deformed portion D1 is formed as a part of the lower peripheral wall portion 31 excluding the portion that fits into the upper peripheral wall portion 21. Further, the deformable portion D1 is formed to be more easily deformed than other portions of the peripheral wall portion 12 in a cross section along the height direction of the peripheral wall portion 12. Specifically, the deformed portion D1 has a thinner wall thickness than other portions of the peripheral wall portion 12, and is also bent. Since the deformable portion D1 is formed thin, it is easier to deform than other portions of the peripheral wall portion 12. FIG. 2 is a perspective view of the lower shell 3. As shown in FIG. 2, the deformed portion D1 of the gas generator 100 is formed in an annular shape on the circumference of the peripheral wall, and extends radially inward of the peripheral wall (that is, toward the first combustion chamber 10X). It is bent to protrude. Note that the technique of the present disclosure is not limited thereto, and the deformed portion D1 may be bent so as to protrude outward in the radial direction of the peripheral wall portion, or may not be formed in an annular shape. For example, the deformed portion may be formed intermittently on the circumference of the peripheral wall portion. That is, in the present disclosure, "the deformable portion D1 is formed" means that the peripheral wall portion 12 is formed so as to be deformed when activated.

Moreover, as shown in FIG. 1, the top plate part 22 has a peripheral part 221 connected to the peripheral wall part 12 and a central part 222 adjacent to the peripheral part 221. Here, the angle between the peripheral part 221 and the peripheral wall part 12 is defined as C1, and the angle between the peripheral part 221 and the central part 222 is defined as C2. At this time, the peripheral portion 221 is inclined so that C1 and C2 both form obtuse angles in a cross section along the height direction of the peripheral wall portion 12. Note that an obtuse angle refers to an angle that is larger than a right angle and smaller than a rectangular angle.

[Ignition device]
The first ignition device 4X and the second ignition device 4Y are fixed to the bottom plate portion 32 of the lower shell 3. Each ignition device is actuated by supply of ignition current to combust the ignition charge housed inside and discharge the combustion products to the outside. This causes the gas generating agent around each ignition device to burn.

[Inner cylinder member]
The first inner cylinder member 5X and the second inner cylinder member 5Y are formed in a cylindrical shape with one end (upper end) closed and the other end (lower end) open. The first inner cylinder member 5X and the second inner cylinder member 5Y are attached along the height direction so as to surround the first ignition device 4X and the second ignition device 4Y, respectively. A fire transfer chamber 51 is formed between the first inner cylinder member 5X and the first ignition device 4X, which is a space in which the transfer charge 110 is placed. On the other hand, a second combustion chamber 10Y, which is a space in which a second gas generating agent 120Y is arranged, is formed between the second inner cylinder member 5Y and the second ignition device 4Y. Further, a plurality of communication holes 52 are formed in the first inner cylinder member 5X and the second inner cylinder member 5Y, which communicate the internal space and the external space. Before each ignition device is activated, the communication hole 52 is closed by a known method such as a sealing tape (not shown) or other closing member.

[Retainer]
The retainer 7 is a member that supports the filter 6. As shown in FIG. 1, the retainer 7 has an annular portion 71 and a cylindrical portion 72. The annular portion 71 is formed in an annular shape, and the peripheral wall portion 12
It is press-fitted into the inner wall surface of the More specifically, the annular portion 71 is press-fitted into the inner wall surface of the peripheral wall portion 12 on the top plate portion 22 side (that is, on the upper side) with respect to the deformed portion D1. The cylindrical portion 72 is formed in a cylindrical shape extending downward from the inner peripheral edge of the annular portion 71, and its lower end is in contact with the inner wall surface of the bottom plate portion 32. The cylindrical portion 72 is not fixed to the bottom plate portion 32. As a result, the retainer 7 is press-fitted into the inner wall surface of the peripheral wall portion 12 on the top plate portion 22 side with respect to the deformed portion D1 in the peripheral wall portion 12, and is not fixed to the bottom plate portion 32. The retainer 7 corresponds to a "holding member" in the present disclosure. Note that the radial width dimension of the annular portion 71 is set so that the cylindrical portion 72 does not come into contact with the deformable portion D1 and deform. Further, in the retainer 7, a cylindrical portion extending upward from the outer peripheral edge of the annular portion 71 may be integrally formed to increase the contact area between the retainer 7 and the inner wall surface of the peripheral wall portion 12 during press-fitting. .

[filter]
As shown in FIG. 1, the filter 6 is formed in a cylindrical shape and is arranged in the combustion chamber 10 so as to surround the gas generating agent 120 and have the gas discharge hole 11 located on the outside in the radial direction. has been done. That is, the filter 6 is arranged between the gas generating agent 120 and the gas discharge hole 11 so as to surround the gas generating agent 120. Of both ends in the axial direction, the filter 6 has one end (upper end surface indicated by reference numeral 61) in contact with the top plate portion 22 of the upper shell 2, and the other end (lower end surface indicated by reference numeral 62) in contact with the annular shape of the retainer 7. It is in a state where it is held by the section 71. That is, the filter 6 is arranged in the housing 1 such that the upper end surface 61 is in contact with the top plate part 22 and the lower end face 62 is located on the top plate part 22 side with respect to the deformed part D1. A gap 13 is formed between the filter 6 and the peripheral wall portion 12. This filter 6 cools the combustion gas by removing heat from the combustion gas when the combustion gas from the gas generating agent disposed in each combustion chamber 10 passes through the filter 6 . In addition to the function of cooling the combustion gas, the filter 6 has a function of filtering the combustion gas by collecting combustion residues contained in the combustion gas. In addition, in FIG. 1, the code|symbol 63 shows the inner peripheral surface of the filter 6, and the code|symbol 64 shows the outer peripheral surface of the filter 6. In this example, the upper end surface 61 of the filter 6 and the top plate section 22 are in direct contact, and the lower end surface 62 and the annular section 71 are in direct contact with each other, but a sealing member such as a gasket is interposed between them. You can.

[Transmission gunpowder]
As the transfer powder 110, in addition to known black powder, a gas generating agent with good ignitability and a combustion temperature higher than that of the first gas generating agent 120X and the second gas generating agent 120Y can be used. The combustion temperature of the transfer powder 110 can be set in the range of 1700 to 3000°C. As such a transfer powder, for example, known ones containing nitroguanidine (34% by weight) and strontium nitrate (56% by weight) can be used. Furthermore, the transfer powder 110 can have various shapes, such as granules, pellets, cylinders, and disks.

[Gas generating agent]
A gas generating agent with a relatively low combustion temperature can be used as the first gas generating agent 120X and the second gas generating agent 120Y, and the combustion temperature can be set in a range of 1000 to 1700°C. As such a gas generating agent, known ones can be used, including, for example, guanidine nitrate (41% by weight), basic copper nitrate (49% by weight), and binders and additives. Further, the first gas generating agent 120X and the second gas generating agent 120Y can have various shapes, such as granular, pellet, cylindrical, and disk shapes.

[motion]
Hereinafter, the operation of the gas generator 100 according to the first embodiment will be described with reference to FIG. 1. First, when a sensor (not shown) detects an impact, an ignition current is supplied to the first ignition device 4X, and the first ignition device 4X is activated. As a result, the transfer powder 110 placed in the transfer chamber 51
burns and combustion gas is generated. The combustion gas of the transfer powder 110 breaks the seal tape that closed the communication hole 52 of the first inner cylinder member 5X and is released from the communication hole 52 to the outside of the fire transfer chamber 51. Then, the combustion gas of the transfer powder 110 comes into contact with the first gas generating agent 120X, and the first gas generating agent 120X is ignited. By burning the first gas generating agent 120X, high temperature and high pressure combustion gas is generated in the first combustion chamber 10X. As this combustion gas passes through the filter 6, the combustion gas is cooled and combustion residues are collected. The combustion gas of the first gas generating agent 120X that has been cooled and filtered by the filter 6 passes through the gap 13, breaks the sealing tape blocking the gas exhaust hole 11, and is released from the gas exhaust hole 11 to the outside of the housing 1. be done. Next, the second ignition device 4Y is activated, the second gas generating agent 120Y arranged in the second combustion chamber 10Y is combusted, and combustion gas is generated. The combustion gas from the second gas generating agent 120Y breaks the seal tape that was blocking the communication hole 52 of the second inner cylinder member 5Y, flows into the first combustion chamber 10X, passes through the filter 6, and exits from the gas discharge hole 11. It is released to the outside of the housing 1. The combustion gases of the first gas generating agent 120X and the second gas generating agent 120Y are discharged to the outside of the housing 1, and then flow into an airbag (not shown). When the airbag inflates, it creates a cushion between the occupant and a rigid structure, protecting the occupant from impact.

By the way, in a gas generator, when the internal pressure of the housing that forms the combustion chamber increases due to combustion of the gas generating agent and generation of combustion gas in the combustion chamber, the housing may deform to expand. That is, the housing may deform to increase its internal volume. Generally, in a housing having a structure in which the top plate and the bottom plate are connected only by a cylindrical peripheral wall, there is no member other than the peripheral wall to connect or fix the top plate and the bottom plate. , the top plate and the bottom plate tend to be more easily deformed than the peripheral wall. As the internal pressure of the housing increases, pressure acts on the top plate and bottom plate in the direction of separating the top plate and bottom plate from the end face of the filter. However, if the housing expands due to the increase in internal pressure, If the top plate or bottom plate is deformed due to this and a gap is formed between the end face of the filter and the top plate or bottom plate, part of the combustion gas will pass through the gap without passing through the filter and be exhausted. There is a concern that it may reach the hole. In other words, there is a possibility that a so-called "short pass" may occur.

Here, FIG. 3 is a diagram showing a state in which the gas generator 100 is in operation. The gas generator 100 according to the first embodiment is configured such that short passes can be suppressed even when the housing 1 is deformed so as to swell due to the pressure of combustion gas. This will be explained in detail below.

When the first ignition device 4X and the second ignition device 4Y operate, the internal pressure of the first combustion chamber 10X increases due to the generation of combustion gas. At this time, as described above, the peripheral wall portion 12 is formed with a deformable portion D1 that is more easily deformed than other portions of the peripheral wall portion 12. Therefore, when the housing 1 deforms to expand due to an increase in the pressure within the first combustion chamber 10X, the deformable portion D1 deforms with priority over other portions of the peripheral wall portion 12. At this time, as shown in FIGS. 1 and 3, the deformable portion D1 deforms from the bent state to extend. Thereby, the height of the peripheral wall portion 12 in the state where the deformable portion D1 is deformed becomes higher than the state before the deformable portion D1 is deformed. That is, the housing 1 deforms so that the entire top plate portion 22 is lifted up relative to the bottom plate portion 32. This increases the volume of the housing 1.

[Action/Effect]
As described above, the gas generator 100 according to the first embodiment is configured such that the deformable portion D1 deforms due to an increase in the pressure within the first combustion chamber 10X, and the height of the peripheral wall portion 12 increases. This makes it difficult for the top plate portion 22 and the bottom plate portion 32 to be affected by the increase in pressure within the first combustion chamber 10X. That is, the expansion of the housing 1 is absorbed by the increase in the volume of the housing 1 due to the deformation of the deformable portion D1, thereby suppressing deformation of the top plate portion 22 and the bottom plate portion 32. Further, in the gas generator 100, the filter 6 is arranged in the housing 1 such that the upper end surface 61 is in contact with the top plate section 22 and the lower end surface 62 is located on the top plate section 22 side with respect to the deformed section D1. ing. In other words, by arranging the filter 6 closer to the top plate section 22 than the deformed section D1, when the deformed section D1 deforms and the height of the peripheral wall section 12 increases, the filter 6 can be lifted up together with the top plate section 22. becomes. In this way, even if the housing 1 is deformed due to an increase in the pressure inside the first combustion chamber 10X, the deformation of the top plate part 22 is suppressed and the filter 6 is lifted together with the top plate part 22, so that as shown in FIG. , the state of contact between the upper end surface 61 of the filter 6 and the top plate portion 22 is maintained. As a result, according to the gas generator 100 according to the first embodiment, it is possible to suppress a short path caused by the separation of the top plate portion 22 from the upper end surface 61 of the filter 6.

Furthermore, the gas generator 100 according to the first embodiment is press-fitted into the inner wall surface of the peripheral wall portion 12 on the top plate portion 22 side with the deformed portion D1 as a reference, and the bottom plate portion 32 has a non-contact portion. A fixed retainer 7 is provided. The gas generator 100 is configured such that the lower end surface 62 of the filter 6 is held by the retainer 7, and the upper end surface 61 of the filter 6 is in contact with the inner wall surface of the top plate portion 22. According to this, since the retainer 7 is press-fitted into the peripheral wall portion 12 on the side closer to the top plate portion 22 than the deformed portion D1 and is not fixed to the bottom plate portion 32, the deformed portion D1 is deformed and the height of the peripheral wall portion 12 is increased. When the height becomes higher, the retainer 7 is lifted toward the top plate portion 22 together with the filter 6 without moving from the press-fitted position. Therefore, even when the deformable portion D1 deforms and the height of the peripheral wall portion 12 increases, the state in which the lower end surface 62 of the filter 6 is held by the retainer 7 is maintained. As a result, in the gas generator 100 according to the first embodiment, short paths caused by the retainer 7 separating from the lower end surface 62 of the filter 6 can also be suppressed. Note that, although the retainer 7 according to the present embodiment has a cylindrical portion 72 extending downward from the annular portion 71 press-fitted into the peripheral wall portion 12, the cylindrical portion 72 is not an essential configuration.

Further, in the gas generator 100 according to the first embodiment, the deformed portion D1 is formed as a part of the peripheral wall portion 12, and further has a wall thickness thinner than other portions of the peripheral wall portion 12, and The circumferential wall portion 12 is bent in a cross section along the height direction. According to this, by forming the deformable portion D1 thin, the deformable portion D1 can be made easier to deform than other parts of the peripheral wall portion 12, and by forming the deformable portion D1 in a bent manner, the height of the peripheral wall portion 12 can be increased. The deformed portion D1 can be deformed so that the height of the deformed portion D1 becomes higher.

Furthermore, in the gas generator 100 according to the first embodiment, the top plate portion 22 includes a peripheral portion 221 connected to the peripheral wall portion 12 and in contact with the upper end surface 61 of the filter 6, and a central portion 222 adjacent to the peripheral portion 221. and has. In a cross section along the height direction of the peripheral wall portion 12, the peripheral portion 221 is inclined so as to intersect with each of the peripheral wall portion 12 and the central portion 222 at an obtuse angle. Therefore, as shown in FIGS. 1 and 3, the peripheral portion 221 contacts the upper end surface 61 of the filter 6 from the outside in the radial direction of the filter 6. As a result, the upper end surface 61 of the filter 6 is supported by the peripheral portion 221 in contact with the radially outward load due to combustion of the gas generating agent. This prevents the filter 6 from shifting due to the radially outward load acting on the filter 6 due to combustion of the gas generating agent, and maintains the state of contact between the upper end surface 61 of the filter 6 and the top plate portion 22. Can be done. As a result, short passes can be suppressed more suitably.

[Modification of Embodiment 1]
A gas generator according to a modification of Embodiment 1 will be described below. In the explanation of the modified example, the differences from the gas generator 100 explained in FIGS. 1 to 3 will be mainly explained, and the same reference numerals will be given to the same points as the gas generator 100, and a detailed explanation will be omitted. do.

[Modification 1 of Embodiment 1]
FIG. 4 is an axial cross-sectional view of a gas generator 100A according to Modification 1 of Embodiment 1. FIG. 4 shows the state of the gas generator 100A before operation. FIG. 5 is a diagram showing a state in which the gas generator 100A is in operation. As shown in FIG. 4, in the gas generator 100A, the lower end surface 62 of the filter 6 is held by the retainer 7A, and the upper end surface 61 of the filter 6 is held by the top plate portion 2.
It is in a state of being in contact with the inner wall surface of No. 2. The retainer 7A related to the gas generator 100A is press-fitted into the inner wall surface of the peripheral wall portion 12, and is further supported by the deformed portion D1 inside the housing 1 by being placed on the deformed portion D1. . The retainer 7A is not fixed to the bottom plate portion 32.

The same effects as the gas generator 100 described above can also be obtained with the gas generator 100A. That is, according to the gas generator 100A, even when the housing 1 is deformed due to an increase in the pressure inside the first combustion chamber 10X, the deformed portion D1 is deformed so that the height of the peripheral wall portion 12 becomes higher, so that the top plate portion The deformation of 22 is suppressed, and the filter 6 is lifted up toward the top plate portion 22 together with the retainer 7A. Therefore, as shown in FIG. 5, the states of contact between the upper end surface 61 of the filter 6 and the top plate portion 22, and between the lower end surface 62 of the filter 6 and the retainer 7A are maintained. As a result, according to the gas generator 100A, short passes occurring at the upper end surface 61 and lower end surface 62 of the filter 6 can be suppressed.

[Modification 2 of Embodiment 1]
FIG. 6 is an axial cross-sectional view of a gas generator 100B according to a second modification of the first embodiment. FIG. 6 shows the state of the gas generator 100B before operation. FIG. 7 is a diagram showing a state in which the gas generator 100B is in operation. As shown in FIG. 6, the peripheral wall portion 12 of the gas generator 100B has a protrusion that protrudes toward the first combustion chamber 10X from the inner wall surface of the peripheral wall portion 12 on the top plate portion 22 side with respect to the deformed portion D1. It has a section 121. The protrusions 121 are formed intermittently on the circumference of the peripheral wall 12 . However, the protrusion according to the present disclosure may be continuously formed in an annular shape on the circumference of the peripheral wall. The gas generator 100B has a structure in which the lower end surface 62 of the filter 6 is held by a protrusion 121 without the above-mentioned retainer 7 or retainer 7A. As shown in FIG. 6, in the gas generator 100B, the lower end surface 62 of the filter 6 is held by the projection 121, and the upper end surface 61 of the filter 6 is in contact with the inner wall surface of the top plate section 22. ing.

Similarly to the gas generator 100 described above, in the gas generator 100B, a short pass due to the separation of the top plate portion 22 from the upper end surface 61 of the filter 6 can be suppressed. Further, since the protrusion 121 is formed on the top plate part 22 side with the deformation part D1 as a reference, when the deformation part D1 is deformed and the height of the peripheral wall part 12 increases, the protrusion 121 is formed on the top plate part 22 side. It will be lifted up together with the section 22. Therefore, as shown in FIG. 7, even when the deformable portion D1 deforms and the height of the peripheral wall portion 12 increases, the state in which the lower end surface 62 of the filter 6 is held by the protruding portion 121 is maintained. As a result, according to the gas generator 100B, short paths caused by the protrusion 121 being separated from the lower end surface 62 of the filter 6 can also be suppressed. Note that when the protrusions 121 are formed intermittently on the peripheral wall 12, there is a gap between the lower end surface 62 of the filter 6 and the protrusions 121 in order to prevent short paths of combustion gas near the lower end of the filter 6. A structure in which an annular sealing member is arranged may also be used. When a sealing member is not used, a structure may be adopted in which the outer circumferential surface 64 of the filter 6 on the lower end surface 62 side is press-fitted into the lower circumferential wall portion 31.

[Modification 3 of Embodiment 1]
FIG. 8 is an axial cross-sectional view of a gas generator 100C according to a third modification of the first embodiment. FIG. 8 shows the state of the gas generator 100C before operation. As shown in FIG. 8, the housing 1 according to the third modification of the first embodiment divides the internal space of the housing 1 into a first combustion chamber 10X and a second combustion chamber 10Y, and abuts the lower end surface 62 of the filter 6. It has a partition wall part 14 that supports it. The partition wall portion 14 is provided between the top plate portion 22 and the bottom plate portion 32 in the height direction of the peripheral wall portion 12 . A through hole 14a is formed in the partition wall portion 14. The first inner cylinder member 5X of the gas generator 100C is attached along the height direction of the peripheral wall 12 so as to surround the first ignition device 4X, and passes through the through hole 14a of the partition wall 14. The top end is open. The second inner cylinder member 5Y of the gas generator 100C is attached along the height direction of the peripheral wall portion 12 so as to surround the second ignition device 4Y, and the upper end portion is closed without penetrating the partition wall portion 14. There is. Note that the second inner cylinder member 5Y may be filled with the transfer charge 110. In the gas generator 100C, the first combustion chamber 10X is defined by the top plate section 22, the bottom plate section 32, the peripheral wall section 12, the partition wall section 14, and the first inner cylinder member 5X. The internal space of the first inner cylinder member 5X is included in the first combustion chamber 10X. Further, a second combustion chamber 10Y is defined by the partition wall portion 14, the peripheral wall portion 12, the bottom plate portion 32, and the second inner cylinder member 5Y. A first gas generating agent 120X that is combusted by the operation of the first igniter 4X is disposed in the first combustion chamber 10X, and a second gas generating agent 120X that is combusted by the operation of the second igniter 4Y is disposed in the second combustion chamber 10Y. agent 120Y is placed.

A partition member P1 is arranged inside the first inner cylindrical member 5X to partition the inner space thereof into upper and lower parts. Thereby, of the internal space of the first inner cylinder member 5X, the space below the partition member P1 (on the first ignition device 4X side) is formed as a transfer chamber 51 in which the transfer charge 110 is arranged. . In addition, a plurality of communication holes 52 are formed in the first inner cylinder member 5X to communicate the internal space (that is, the first combustion chamber 10X) and the second combustion chamber 10Y. The communication hole 52 is closed with a seal tape (not shown) or the like before the second ignition device 4Y is activated.

As shown in FIG. 8, in the gas generator 100C, a deformed portion D1 is formed as a part of the peripheral wall portion 12 at a predetermined height position on the top plate portion 22 side with respect to the partition wall portion 14. It is formed on the circumference of the peripheral wall portion 12. The deformed portion D1 has a thinner wall thickness than other portions of the peripheral wall portion 12 in a cross section along the height direction of the peripheral wall portion 12, and is formed in a bent manner. Further, the retainer 7 of the gas generator 100C is press-fitted into the inner wall surface of the peripheral wall 12 on the top plate 22 side with the deformed portion D1 as a reference, and is not fixed to the partition wall 14. It becomes. Further, the filter 6 of the gas generator 100C has a lower end surface 62 held by the retainer 7, and an upper end surface 61 in contact with the inner wall surface of the top plate portion 22.

When such a gas generator 100C operates, first, the first igniter 4X operates, the transfer charge 110 disposed in the transfer chamber 51 of the first combustion chamber 10X burns, and combustion gas is generated. . As the partition member P1 is burned and removed by the combustion gas of the transfer powder 110, the combustion gas comes into contact with the first gas generating agent 120X, and the first gas generating agent 120X is ignited. Combustion gas is generated in the first combustion chamber 10X by burning the first gas generating agent 120X. The combustion gas of the first gas generating agent 120X passes through the filter 6 and is discharged from the gas discharge hole 11 to the outside of the housing 1. Next, the second ignition device 4Y is activated, the second gas generating agent 120Y arranged in the second combustion chamber 10Y is combusted, and combustion gas is generated. The combustion gas of the second gas generating agent 120Y breaks the sealing tape that blocked the communication hole 52 of the first inner cylinder member 5X, flows into the first combustion chamber 10X, passes through the filter 6, and exits from the gas discharge hole 11. It is released to the outside of the housing 1.

The same effects as those of the gas generator 100 described above can also be obtained with the gas generator 100C. That is, according to the gas generator 100C, even when the housing 1 is deformed due to an increase in the pressure inside the first combustion chamber 10X, the deformed portion D1 is deformed so that the height of the peripheral wall portion 12 becomes higher, so that the top plate portion 22 is suppressed from deforming, and the filter 6 is lifted up together with the top plate portion 22. Therefore, the state of contact between the upper end surface 61 of the filter 6 and the top plate portion 22 is maintained, and a short path caused by the separation of the top plate portion 22 from the upper end surface 61 of the filter 6 can be suppressed. Further, since the retainer 7 is press-fitted into the peripheral wall portion 12 on the side closer to the top plate portion 22 than the deformed portion D1 and is not fixed to the partition wall portion 14, the deformed portion D1 is deformed and the height of the peripheral wall portion 12 is increased. When the height increases, the retainer 7 will be lifted together with the top plate portion 22. Therefore, even when the deformed portion D1 deforms and the height of the peripheral wall portion 12 increases, the state in which the retainer 7 holds the lower end surface 62 of the filter 6 is maintained, and short circuits may occur due to the retainer 7 separating from the lower end surface 62 of the filter 6. Passes can also be suppressed.

<Embodiment 2>
FIG. 9 is an axial cross-sectional view of the gas generator 200 according to the second embodiment. FIG. 9 shows the state of the gas generator 200 before operation. The gas generator 200 is configured as a so-called single-type gas generator that includes only one ignition device. In the first embodiment described above, the ignition unit includes a plurality of ignition devices fixed to the second wall portion, and a plurality of cylindrical inner cylinder members surrounding each ignition device correspond to each of the plurality of ignition devices. Although the description has been given of a gas generator configured to be attached along the height direction of the peripheral wall, the technology according to the present disclosure can also be applied to a single type gas generator. The gas generator 200 according to Embodiment 2 will be described below, focusing on the differences from the gas generator 100, and the same reference numerals will be given to the same points as the gas generator 100, and a detailed explanation will be omitted. .

As shown in FIG. 9, the gas generator 200 according to the second embodiment includes an ignition device 4, an inner cylinder member 5, a filter 6, a retainer 7, a transfer charge 110, a gas generating agent 120, and the like. and a housing 1 for accommodating the device. A combustion chamber 10 in which a gas generating agent 120 is placed is defined by the top plate 22, bottom plate 32, and peripheral wall 12 of the housing 1. Moreover, the inner cylinder member 5 is formed in a cylindrical shape with one end (upper end) closed and the other end (lower end) open, and is attached along the height direction so as to surround the ignition device 4. A transfer chamber 51 is formed between the inner cylinder member 5 and the ignition device 4, and a transfer charge 110 is disposed therein. In the gas generator 200, the ignition device 4 corresponds to the "ignition section" according to the present disclosure.

In the gas generator 200, the deformed portion D1 is formed as a part of the peripheral wall portion 12. The deformed portion D1 has a thinner wall thickness than other portions of the peripheral wall portion 12 in a cross section along the height direction of the peripheral wall portion 12, and is formed in a bent manner. Further, the retainer 7 is press-fitted into the inner wall surface of the peripheral wall portion 12 on the top plate portion 22 side with respect to the deformed portion D1 in the peripheral wall portion 12, and is not fixed to the bottom plate portion 32. Further, the filter 6 of the gas generator 200 has a lower end surface 62 held by the retainer 7 and an upper end surface 61 in contact with the inner wall surface of the top plate section 22 .

The same effects as the gas generator 100 according to the first embodiment can also be obtained in the gas generator 200. That is, according to the gas generator 200, even when the housing 1 is deformed due to an increase in the pressure within the combustion chamber 10, the deformed portion D1 is deformed so that the height of the peripheral wall portion 12 becomes higher, so that the top plate portion 22 is deformed. Deformation is suppressed and the filter 6 is lifted up together with the top plate portion 22. Therefore, the state of contact between the upper end surface 61 of the filter 6 and the top plate portion 22 is maintained, and a short path caused by the separation of the top plate portion 22 from the upper end surface 61 of the filter 6 can be suppressed. Further, since the deformable portion D1 is press-fitted into the peripheral wall portion 12 on the side closer to the top plate portion 22 than the deformable portion D1 and is not fixed to the bottom plate portion 32, the deformable portion D1 is deformed and the height of the peripheral wall portion 12 becomes higher. At times, the retainer 7 will be lifted up together with the top plate section 22. Therefore, even when the deformed portion D1 deforms and the height of the peripheral wall portion 12 increases, the state in which the retainer 7 holds the lower end surface 62 of the filter 6 is maintained, and short circuits may occur due to the retainer 7 separating from the lower end surface 62 of the filter 6. Passes can also be suppressed.

<Others>
Although preferred embodiments of the present disclosure have been described above, each aspect disclosed herein can be combined with any other feature disclosed herein.

100,200 Gas generator 1 Housing 11 Gas discharge hole 12 Surrounding wall portion 121 Projection portion 2 Upper shell 22 Top plate portion (an example of the first wall portion)
3 Lower shell 32 Bottom plate part (an example of the second wall part)
4, 4X, 4Y Ignition device (example of ignition part)
5, 5X, 5Y Inner cylinder member 6 Filter 61 Upper end surface (one end of filter)
62 Lower end surface (other end of filter)
7,7A retainer (an example of a holding member)
10, 10X, 10Y Combustion chamber 120, 120X, 120Y Gas generating agent D1 Displacement part

Claims (7)

An ignition part;
a combustion chamber in which a gas generating agent that is combusted by the operation of the ignition section is disposed;
a cylindrical peripheral wall; a first wall provided at one end of the peripheral wall; and a first wall provided at the other end of the peripheral wall to face the first wall; a second wall part that defines the combustion chamber together with a first wall part and to which the ignition part is fixed, the housing having a gas discharge hole that communicates the combustion chamber with the outside of the housing. housing and
a cylindrical filter disposed in the combustion chamber so as to surround the gas generating agent and with the gas discharge hole located on the outside thereof;
A gas generator comprising:
The peripheral wall portion is formed on the circumference of the peripheral wall portion at a predetermined height from the second wall portion, and the height of the peripheral wall portion is increased by an increase in pressure within the combustion chamber caused by activation of the ignition portion. It has a deformed part that deforms to become higher,
The filter is arranged in the housing such that one end thereof is in contact with the first wall portion, and the other end is located on the first wall side with respect to the deformed portion.
gas generator. The deformable portion is formed as a part of the peripheral wall portion, and further has a wall thickness thinner than other portions of the peripheral wall portion, and is bent in a cross section along the height direction of the peripheral wall portion. has been,
The gas generator according to claim 1. further comprising a holding member that is press-fitted into an inner wall surface of the peripheral wall portion on the first wall side with respect to the deformed portion in the peripheral wall portion and is not fixed to the second wall portion;
The other end of the filter is held by the holding member, and the one end of the filter is in contact with the inner wall surface of the first wall.
The gas generator according to claim 1 or claim 2. further comprising a holding member supported by the deformable portion formed by bending inside the housing and not fixed to the second wall portion;
The other end of the filter is held by the holding member, and the one end of the filter is in contact with the inner wall surface of the first wall.
The gas generator according to claim 2. The peripheral wall further includes a protrusion protruding toward the combustion chamber from an inner wall surface of the peripheral wall on the first wall side with respect to the deformed part,
The other end of the filter is held by the protrusion, and the one end of the filter is in contact with the inner wall surface of the first wall.
The gas generator according to claim 1 or claim 2. The first wall portion has a peripheral portion connected to the peripheral wall portion and in contact with the one end of the filter, and a central portion adjacent to the peripheral portion,
In a cross section along the height direction of the peripheral wall part, the peripheral part is inclined to intersect with each of the peripheral wall part and the central part at an obtuse angle.
The gas generator according to any one of claims 1 to 5. The ignition unit includes a plurality of ignition devices,
the plurality of igniters are fixed to the second wall,
A plurality of cylindrical inner cylinder members surrounding each of the plurality of ignition devices are attached along the height direction of the peripheral wall portion, corresponding to each of the plurality of ignition devices,
The gas generator according to any one of claims 1 to 6.

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