JP2007131254A - Gas generator for occupant restraint device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas generator for an occupant restraint device with sufficient filtration efficiency of a burned gas. <P>SOLUTION: The burned gas generated in a combustion chamber 6 flows into a first annular closed space 17a from a gas flowing-in surface 24a of a filter 13a, passes through the filter 13a and flows out from a gas flowing-out surface 25a. The similar manner is also performed in a filter 13b. Thus, the filtration efficiency is enhanced by passing the burned gas through one filter twice. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a gas generator for a person restraining device such as an airbag device.

In a gas generator (pyro-type gas generator) that uses a solid gas generating agent, the solid gas generating agent and ignition means for igniting / combusting the solid gas generating agent are arranged inside the outer shell container that forms the housing, and further combustion A filter is used in combination for gas cooling and residue collection. In the pyro type gas generator, it is important how efficiently the residue is collected and the gas is cooled, and the following conventional techniques are known.
JP 2001-39261 A

  In the prior art, a partition plate is arranged on the inner side of the filter, and the partition plate is provided with a deflection nozzle that discharges combustion gas in a tangential direction (outward on the spiral). When the gas passes through the filter, the passage distance becomes longer, so that the gas cooling efficiency and the residue collecting effect are enhanced. However, since the gas flows only in one direction with respect to the filter, residue is likely to adhere to the gas inflow surface of the filter, and clogging is likely to occur.

  The present invention provides a gas generator for a personnel restraint device that can improve the efficiency of gas cooling and residue collection by using one filter divided into a gas inflow surface and an outflow surface. The task is to do.

(Claim 1)
As a means for solving the problems, the present invention
In a housing having a plurality of gas discharge ports, an ignition means, a gas generating agent, and a gas generator for a person restraining device having a filter disposed between the gas generating agent filling space and the gas discharge port,
In the process where the ignition means is activated and the combustion gas generated by the ignition and combustion of the gas generating agent passes through the filter and is discharged from the gas discharge port,
The combustion gas passes through a first passage surface that is a part of one surface side of the filter and flows into a closed space, and then passes through the opposite surface of the filter from the closed space to define the first passage surface. Provided is a gas generator for a personnel restraint device that flows out from a different second passage surface and is discharged from a gas discharge port.

  When combustion gas passes through the filter, combustion residue tends to accumulate on the inflow surface of the filter, so that the inflow surface of the filter is likely to be clogged with combustion residue, and the opposite surface of the inflow surface is less likely to be clogged. There is a tendency.

  In the present invention, one filter is divided into two parts, a gas inflow surface (first passage surface) and a gas outflow surface (second passage surface), so that both one surface and the opposite surface of the filter can be used. Therefore, the efficiency (cooling and filtering performance per unit mass of the filter) of gas cooling and combustion residue collection (filtration) is improved.

(Claim 2)
The present invention provides other means for solving the problems,
The filter has a donut shape in plan, and is disposed so that the closed space is formed on at least one of the ceiling surface and the bottom surface of the housing, and is a portion close to the gas generating agent filling space The gas generator for personnel restraint device according to claim 1, wherein the first passage surface and the portion far from the gas filling space serve as the second passage surface.

(Claim 3)
In another aspect of the present invention, the filter has an annular groove on one surface side, and the closed space is provided between the annular groove and at least one of a ceiling surface and a bottom surface of the housing. A gas generator for a personnel restraint device according to claim 2, wherein the gas generator is formed.

  By providing the closed space as in the inventions of claims 2 and 3, the combustion gas flowing into the closed space from the gas inflow surface (first passage surface) once collides with the ceiling surface and the bottom surface of the housing. Since the combustion residue that could not be filtered on one passing surface adheres to the ceiling surface and bottom surface of the housing and is cooled, the cooling and filtering efficiency is further improved.

(Claim 4)
As another means for solving the problem, the present invention includes an inflow of combustion gas from the first passage surface of the filter to the closed space and an outflow of combustion gas from the closed space to the second passage surface of the filter. The gas generator for personnel restraint devices according to any one of claims 1 to 3, which is controlled by a partition wall.

  By providing such a partition wall, it becomes easy to use one filter divided into two parts, a gas inflow surface (first passage surface) and a gas outflow surface (second passage surface). Further, the gas flowing toward the first passage surface and the gas flowing out from the second passage surface can be smoothly discharged without interference, and the combustion residue once attached to the gas inflow surface becomes the effluent gas. Is not peeled off from the gas inflow surface and is not discharged out of the housing together with the gas.

(Claim 5)
The present invention provides other means for solving the problems,
The partition wall is a cylindrical member that partitions the housing in an axial direction;
The opening of the tubular member is in contact with the filter, and the filter is separated so that the first passage surface is located inside the tubular member and the second passage surface is located outside. A gas generator for a personnel restraint device according to claim 4 is provided.

  By providing such a partition wall, the combustion gas collides with the partition wall and is easily guided to the first passage surface and passes through the first passage surface and the second passage surface. It becomes easy to divide and use two surfaces, a surface (first passage surface) and a gas outflow surface (second passage surface).

(Claim 6)
The present invention provides other means for solving the problems,
The partition wall includes an annular flat plate, and an annular wall protruding from or near the center in the width direction on one surface side of the annular flat plate, and the annular flat plate is formed between the annular outer peripheral surface and the annular wall. It has the 1st partition wall isolate | separated by the cyclic | annular inner peripheral surface which has a some 1st gas passage port, and the 2nd partition wall which consists of a cylindrical member which has a some 2nd gas passage port in the edge part side. And
The first partition wall is disposed in a radial direction of the housing with the annular wall being in contact with the filter, and the second partition wall has an inner peripheral surface that contacts the outer periphery of the annular flat plate. And the periphery of the opening is disposed in contact with the filter,
A first space formed by the annular inner peripheral surface of the first partition wall and the annular wall is located on the first passage surface, and is formed by the annular outer peripheral surface of the first partition wall and the second partition wall. The second space to be formed is located on the second passage surface;
Combustion gas enters the first space from the first gas passage port, passes through the first passage surface, passes through the closed space, passes through the second passage surface, enters the second space, and enters the first space. The gas generator for personnel restraint device according to claim 4, wherein the gas generator is discharged from the gas outlet through the two gas passages.

  By providing such a partition wall, the combustion gas is easily guided to the first passage surface and passes through the first passage surface and the second passage surface, so that one filter is disposed on the gas inflow surface (first passage surface). ) And a gas outflow surface (second passage surface).

(Claim 7)
The present invention provides other means for solving the problems,
The gas generating agent filling space and the filter are partitioned by a cylindrical partition,
The cylindrical partition wall has a plurality of openings for passing the combustion gas generated by the ignition combustion of the gas generating agent;
The gas generator for a personnel restraint device according to any one of claims 1 to 5, wherein an outflow direction of the combustion gas flowing out from the opening is controlled in the filter direction.

  Combustion gas generated from the gas generant filling space (generally referred to as “combustion chamber”) flows out from the opening of the cylindrical partition wall. At this time, the combustion gas flows in the filter direction. By doing so, the gas can be cooled and filtered more smoothly. Therefore, when the filter is on the ceiling surface of the housing, the combustion gas is controlled to flow upward, and when the filter is on the bottom surface of the housing, the combustion gas is controlled to flow downward. It is preferable to arrange the opening of the cylindrical partition wall and the filter at an interval because the gas inflow surface can be widened.

  The control means of the gas flow direction from the opening is not particularly limited, and the method is to make the cylindrical partition wall thick and form the opening obliquely upward or downward, upward or downward to the outlet of the opening. A method of providing a gas flow guide member or the like can be applied.

  In the gas generator of the present invention, one filter is divided into two parts, a gas inflow surface and a gas outflow surface, and by passing the combustion gas twice, the mass of the combustion gas is increased without increasing the overall mass. Filtration and cooling capacity is increased.

(1) Gas Generator for Personnel Restraint Device in FIG. 1 FIG. 1 is a longitudinal sectional view of a first embodiment of a gas generator of the present invention. FIG. 2 is a perspective view of the filter used in FIG. 3 and 4 are perspective views of different forms of the cylindrical partition wall used in FIG.

  A substantially cylindrical inner cylinder member 4 is disposed in a housing 3 formed by joining a diffuser shell 1 having a gas discharge port 10 closed with a seal tape and a closure shell 2 that forms an internal housing space together with the diffuser shell 1. Has been placed.

  The diffuser shell 1, the closure shell 2, and the inner cylinder member 4 are formed using various steel plates such as stainless steel, and both shells are joined by, for example, electron beam welding, laser welding, TIG welding, or prosection welding. Yes.

  An ignition means accommodation chamber 5 is provided inside the inner cylinder member 4, and a combustion chamber (gas generating agent filling space) 6 is provided outside. The ignition means accommodating chamber 5 accommodates an ignition means comprising an electric ignition type igniter 7 and a transfer powder 8 that is ignited and burned when the igniter 7 is operated to generate a flame. The combustion chamber 6 contains a gas generating agent 9 that is ignited and burned by the flame of the charge transfer agent 8 and generates combustion gas.

  The inner cylinder member 4 that separates the combustion chamber 6 and the ignition means accommodation chamber 5 is provided with a plurality of heat transfer holes 11, and the heat transfer holes 11 are ruptured by the flame of the charge 8. 12 is blocked.

  The igniter 7 is fixed in an iron initiator collar 23, and the skirt of the initiator collar 23 is fixed by caulking at the lower end of the inner cylinder member 4.

  Outside the combustion chamber 6, filter means 13 a and 13 b having a donut-like planar shape are arranged on the ceiling surface of the diffuser shell 1 and the bottom surface of the closure shell 2. The filter means 13a, 13b purifies and / or cools the combustion gas generated by the combustion of the gas generating agent 9, and can be formed using a laminated wire mesh or a compression molded wire.

  As shown in FIG. 2, the filter means 13a has an outer annular wall 14a and an inner annular wall 15a on its outer and inner peripheral edges, so that a first annular groove 16a is formed. In the filter means 13a, the outer annular wall 14a and the inner annular wall 15a are pressed against the ceiling surface of the diffuser shell 1 to form a first annular closed space 17a.

  As shown in FIG. 2, the filter means 13b has an outer annular wall 14b and an inner annular wall 15b on the outer and inner peripheral edges thereof, so that a first annular groove 16b is formed. In the filter means 13b, the outer annular wall 14b and the inner annular wall 15b are pressed against the bottom surface of the closure shell 2 to form a second annular closed space 17b.

  A cylindrical partition wall 18 is disposed between the filter 13a and the filter 13b. The cylindrical partition wall 18 is positioned by fitting one end opening into a second annular groove 13c formed in the filter 13a and the other end opening into a second annular groove 13d formed in the filter 13b. It is fixed together.

  The cylindrical partition wall 18 forms a gas inflow surface (first passage surface) 24a and a gas outflow surface (second passage surface) 25a in the filter 13a, and a gas inflow surface (first passage surface) 24b and gas in the filter 13b. An outflow surface (second passage surface) 25b is formed. The opposite side surfaces of the gas outflow surfaces (second passage surfaces) 25a and 25b become the second gas inflow surfaces 26a and 26b.

  The combustion chamber 6 and the filters 13a and 13b are separated by a cylindrical partition wall 19. The cylindrical partition wall 19 has an opening at one end sandwiched between the filter 13b and the retainer 30, the opening at the other end is in contact with the filter 13a, and an inward flange portion 19b is a diffuser shell. 1 is in contact with the ceiling surface.

  The cylindrical partition wall 18 and the cylindrical partition wall 19 are arranged so as to form a first gap 20 therebetween, and a second gap 21 is also formed between the cylindrical partition wall 18 and the peripheral wall surface of the housing 3. Has been. The first gap 20 faces the gas inflow surfaces 24a and 24b, and the second gap 21 faces the gas outflow surfaces 25a and 25b.

  A plurality of openings 22 are formed in the peripheral wall surface 19 a of the cylindrical partition wall 19. The opening 22 is formed so as to open to the cylindrical partition wall 18, and the gas colliding with the cylindrical partition wall 18 is guided to the filters 13 a and 13 b while changing its direction in the axial direction. The opening direction of the opening 22 (combustion gas flow control direction) is also such as to control the direction of gas discharged from the peripheral wall surface 19a of the cylindrical partition wall 19 as shown in FIGS. It may be. The number and arrangement state of the openings 22 are not particularly limited, but the arrangement state can be arranged in a staggered manner as shown in FIG.

  A cylindrical partition wall 19 having a different form from FIG. 1 shown in FIG. 3 has an opening 22a and an opening 22b as openings. The opening 22a is formed by protruding so as to open obliquely upward on the peripheral wall surface 19a, and the opening 22b is formed by protruding so as to open obliquely downward. The openings 22a and 22b are formed by cutting the peripheral wall surface 19a of the cylindrical partition wall 19 and pushing it out from the inside to the outside.

  As indicated by arrows in FIG. 3, the combustion gas flows upward (in the direction of the filter 13a) from the opening 22a, and flows downward (in the direction of the filter 13b) from the opening 22b.

  4 has an opening 22c and an opening 22d as openings. The opening 22c has an opening 31a formed in the peripheral wall surface 19a and a guide member 32a, and the opening 22d has an opening 31b formed in the peripheral wall surface 19a and a guide member 32b.

  As indicated by arrows in FIG. 4, the combustion gas flows upward (in the direction of the filter 13a) from the opening 22c, and flows downward (in the direction of the filter 13b) from the opening 22d.

  3 and 4 both show a cylindrical partition wall that allows gas to flow in the axial direction, but has an opening that can control all or part of the gas flow in the circumferential direction. But you can.

  Next, the operation of the gas generator shown in FIG. 1 having the cylindrical partition wall 19 shown in FIG. 3 will be described. The electric ignition igniter 7 is activated by the operation signal output when the sensor senses the impact, and the charge 8 is ignited and burned. The flame in which the transfer powder 8 burns breaks the seal tape 12 from the transfer hole 11 of the inner cylinder member 4 and is ejected to the combustion chamber 6 to ignite and burn the gas generating agent 9 to generate combustion gas.

  The combustion gas flows out from the openings 22 a and 22 b formed in the cylindrical partition wall 19 and enters the first space 20. At this time, the combustion gas flowing out from the opening 22a flows in the direction of the filter 13a due to the action of the opening 22a and the cylindrical partition wall 18, and the combustion gas flowing out from the opening 22b flows into the opening 22b and the cylindrical partition wall. 18 flows in the direction of the filter 13b.

  The combustion gas that flows to the filter 13a side passes through the filter 13a from the gas inflow surface 24a and enters the first annular closed space 17a, and the combustion gas that flows to the filter 13b side passes through the filter 13b from the gas inflow surface 24b. Pass through and enter the second annular closed space 17b. At this time, the combustion residue in the combustion gas adheres to the gas inflow surfaces 24a and 24b. Thereafter, since the combustion gas collides with the wall surface (ceiling surface or bottom surface) of the diffuser shell 1 or the closure shell 2, the combustion residue that cannot be completely filtered by the gas inflow surfaces 24a and 24b adheres to the wall surface and the gas is cooled. Is done.

  The combustion gas that has flowed into the first annular closed space 17a and the second annular closed space 17b flows into the second space 21 from the gas outlet surfaces 25a and 25b through the second gas inlet surfaces 26a and 26b, respectively. At this time, even on the second gas inflow surfaces 26a and 26b, the combustion residue that has not adhered to the wall surfaces of the diffuser shell 1 and the closure shell 2 is filtered.

  Thereafter, the combustion gas that has flowed into the second space 21 breaks the seal tape that closes the gas discharge port 10 and is discharged outside the housing 3.

  In the present invention, as described above, the combustion gas that has passed through the filters 13a and 13b flows out from the opposite surface again. For this reason, in addition to passing through one filter twice, the combustion residue is collected even when the combustion gas hits the inner wall surface of the housing, so the collection efficiency of the combustion residue is good.

(2) Gas Generator for Personnel Restraint Device in FIG. 5 FIG. 5 is a vertical partial sectional view of a gas generator having a different form from that in FIG. The same numbers as those in FIG. 1 mean the same thing.

  A filter 13 is disposed on the bottom surface side of the closure shell 2 and a first partition wall 41 and a second partition wall 61 are disposed outside the inner cylinder member 4 disposed in the housing 3.

  The filter 13 has an outer annular wall 14 on the outer peripheral edge thereof, and is disposed in a state where the outer circumferential surface of the outer annular wall 14 is in contact with the circumferential wall of the closure shell 2. And the annular closed space 17 formed from the inner cylinder member 4 is formed.

  The first partition wall 41 includes an annular flat plate 42 and an annular wall 43 that protrudes from the central portion in the width direction on one surface side of the annular flat plate 42. The inner periphery of the annular flat plate 42 is in pressure contact with the step portion formed in the inner cylinder member 4, and the outer periphery is in pressure contact with the step portion of the second partition wall 61. The peripheral edge of the annular wall 43 is fitted in an annular groove formed in the filter 13.

  The second partition wall 61 is formed of a cylindrical member having a plurality of second gas passage ports 62 on one end side (filter 13 side), and the other end opening side has an inward flange portion 62a. is doing. As for the 2nd partition wall 61, the inward flange part 62a is press-contacted to the ceiling surface of the diffuser shell 1, an inner peripheral surface is press-contacted to the outer periphery of the cyclic | annular flat plate 42, and the peripheral edge of one end opening is press-contacted to the filter 13. .

  A space formed by a partial circumferential surface (annular inner circumferential surface) of the first partition wall 41, the annular wall 43, the filter 13, and the inner cylinder member 4 is a first space 51, and the filter 13 facing the first space 51. Becomes the gas inflow surface (first passage surface) 24.

  A space formed by a partial peripheral surface (annular outer peripheral surface) of the first partition wall 41, the annular wall 43, the filter 13 and the second partition wall 61 is the second space 52, and the filter facing the second space 52 Reference numeral 13 denotes a gas outflow surface (second passage surface) 25. The opposite side of the gas outflow surface 25 is the second gas inflow surface 26.

  The filter 13, the first partition wall 41, and the second partition wall 61 are press-contacted with no gap at each contact portion and fixed to each other by adjusting the arrangement state of the inner cylinder member 4 and the inner wall surface of the housing 3. Is in a state.

  Next, the operation of the gas generator shown in FIG. 5 will be described. The electric ignition igniter 7 is activated by the operation signal output when the sensor senses the impact, and the charge 8 is ignited and burned. The flame burned by the transfer powder 8 is ejected from the transfer hole 11 of the inner cylinder member 4 to the combustion chamber 6 to ignite and burn the gas generating agent 9 to generate combustion gas.

  The combustion gas flows into the first space 51 from the first gas passage port 44, then passes through the filter 13 from the gas inflow surface 24 and flows into the annular closed space 17. At this time, since the combustion gas collides with the bottom surface of the closure shell 2, the combustion residue that could not be filtered by the gas inflow surface 24 adheres to the bottom surface and is cooled.

  The combustion gas that has flowed into the closed annular space 17 flows out from the gas outflow surface 25 into the second space 52 through the second gas inflow surface 26. At this time, the combustion residue also enters the second gas inflow surface 26. Is filtered.

  Thereafter, the combustion gas that has flowed into the second space 52 flows into the gap 63 through the second gas passage port 62, breaks the seal tape that closes the gas discharge port 10, and is discharged to the outside of the housing 3. A part of the gas that has flowed into the closed annular space 17 does not enter the second space 52 and goes directly to the gap 63 from the gas outflow surface.

  In the present invention, as described above, the combustion gas that has passed through the filter 13 flows out from the opposite surface again. For this reason, in addition to passing through one filter twice, the combustion residue is collected even when the combustion gas hits the inner wall surface of the housing, so the collection efficiency of the combustion residue is good.

  The first gas passage port 44 and the second gas passage port 62 may be other than the illustrated form. For example, the inner peripheral edge portion (the portion in contact with the inner cylinder 4) of the first partition wall 41 and one end portion (the portion in contact with the filter 13) of the second partition wall 61 are partially notched, and the notch portion is an inner cylinder member. 4 or the filter 13 may be formed.

The longitudinal cross-sectional view of a gas generator. The perspective view of the filter used in FIG. The perspective view of another form of the cylindrical partition used in FIG. The perspective view of another form of the cylindrical partition used in FIG. The fragmentary longitudinal cross-section of the gas generator of another form.

Explanation of symbols

DESCRIPTION OF SYMBOLS 3 Housing 4 Inner cylinder member 6 Combustion chamber 7 Igniter 9 Gas generating agent 10 Gas exhaust port 13a, 13b Filter 18 Cylindrical partition wall 19 Cylindrical partition

Claims (7)

In a housing having a plurality of gas discharge ports, an ignition means, a gas generating agent, and a gas generator for a person restraining device having a filter disposed between the gas generating agent filling space and the gas discharge port,
In the process where the ignition means is activated and the combustion gas generated by the ignition and combustion of the gas generating agent passes through the filter and is discharged from the gas discharge port,
The combustion gas passes through a first passage surface that is a part of one surface side of the filter and flows into a closed space, and then passes through the opposite surface of the filter from the closed space to define the first passage surface. A gas generator for a personnel restraint device that flows out from a different second passage surface and is discharged from a gas discharge port.   The filter has a donut shape in plan, and is disposed so that the closed space is formed on at least one of the ceiling surface and the bottom surface of the housing, and is a portion close to the gas generating agent filling space The gas generator for personnel restraint system according to claim 1, wherein the first passage surface and a portion far from the gas filling space serve as the second passage surface.   The personnel restraint according to claim 2, wherein the filter has an annular groove on one surface side, and the closed space is formed between the annular groove and at least one of a ceiling surface and a bottom surface of the housing. Gas generator for equipment.   The inflow of combustion gas from the first passage surface of the filter to the closed space and the outflow of combustion gas from the closed space to the second passage surface of the filter are controlled by a partition wall. 4. A gas generator for a personnel restraint device according to any one of 3 above. The partition wall is a cylindrical member that partitions the housing in an axial direction;
The opening of the tubular member is in contact with the filter, and the filter is separated so that the first passage surface is located inside the tubular member and the second passage surface is located outside. A gas generator for a person restraining apparatus according to claim 4. The partition wall includes an annular flat plate and an annular wall protruding from the width direction central portion on the one surface side of the annular flat plate or the vicinity thereof, and the annular flat plate is formed between the annular outer peripheral surface and the annular wall. A first partition wall separated into an annular inner peripheral surface having a plurality of first gas passage ports; and a second partition wall made of a cylindrical member having a plurality of second gas passage ports on the end side. And
The first partition wall is disposed in a radial direction of the housing with the annular wall in contact with the filter, and the second partition wall has an inner peripheral surface that is in contact with an outer periphery of the annular flat plate. And the periphery of the opening is disposed in contact with the filter,
A first space formed by the annular inner peripheral surface of the first partition wall and the annular wall is located on the first passage surface, and is formed by the annular outer peripheral surface of the first partition wall and the second partition wall. The second space to be formed is located on the second passage surface;
Combustion gas enters the first space from the first gas passage port, passes through the first passage surface, passes through the closed space, passes through the second passage surface, enters the second space, and enters the first space. The gas generator for a personnel restraint device according to claim 4, wherein the gas generator passes through the two gas passage ports and is discharged from the gas discharge port. The gas generating agent filling space and the filter are partitioned by a cylindrical partition,
The cylindrical partition wall has a plurality of openings for passing the combustion gas generated by the ignition combustion of the gas generating agent;
The gas generator for a personnel restraint device according to any one of claims 1 to 5, wherein an outflow direction of the combustion gas flowing out from the opening is controlled in the filter direction.

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