JP2007091184A - Gas generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas generator for an occupant restraining device, which does not permit parts arranged inside to be displaced or to come off. <P>SOLUTION: A retainer 50 is fitted in one end of a tubular housing 20, and an arrowhead part 24c of a rod 24 is tightly inserted in a hole of the retainer 50. A disc part 24a of the rod 24 is pressurized in an ignition means chamber housing 32. The rod 24 and the retainer 50 are fixed to each other, so as to prevent them from being displaced or coming-off. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a gas generator used in a vehicle personnel restraint device such as an air bag, an inflatable seat belt, a pedestrian protection device, and the like.

  In a gas generator that inflates an air bag or the like in a vehicle occupant restraint device or a pedestrian protection device, an air bag (restraint device) is connected to the gas exhaust port, so that an ignition sword wire that obstructs the bag connection near the gas exhaust port A structure in which there is no igniter or the like to be connected is preferable.

  Patent Document 1 discloses an inflator using a pressurized gas, in which an igniter and a gas discharge port are separated. In a gas generator that uses pressurized gas, a rupture plate that serves as a closing means is used to close the gas discharge port. However, during operation, the rupture plate must be cleaved to open the gas discharge path. In Patent Document 1, a structure is employed in which a rupturable plate is cleaved by a rod operated by a high-temperature and high-pressure gas generated by the operation of an ignition means.

  In the invention of Patent Document 1, a squib 44 is attached to one end of an inflator container 12 containing pressurized gas. The squib 44 is attached to one end portion of the combustion chamber 16 formed at one end portion of the housing 12 and is disposed in a state of being fitted into the housing 12. The combustion chamber 16 is further provided with a gas generating agent 34 that is ignited by the operation of the squib 44 and generates a high-temperature and high-pressure gas. By pushing the rod 74 to the right, the seal 80 serving as a rupture plate is cleaved. . The rod is fixed so as to be supported by a sleeve 76 attached to the seal 80. In the gas generator having such a structure, in order to operate reliably, it is necessary to prevent the fixed position of the rod from being displaced by an external impact or vibration.

USP 3,856,180 specification

  In the inflator of Patent Document 1, the end of the rod 74 is supported in the split sleeve 76 by friction, but the diameter of the rod 74 is substantially constant and the sleeve 76 is fixed to the seal 80 by counter bore 78. The sleeve 76 is merely supported inside, and the sleeve 76 may come off due to vibration from the outside, and the rod 74 is not sufficiently fixed.

  The present invention is a gas generator that is provided at a position where the igniter and the gas discharge port are separated from each other and breaks the closing means of the gas discharge path to the gas discharge port with a rod, and the rod is fixed with a simple structure. It is an object of the present invention to provide a gas generator for a vehicle personnel restraint device.

As a means for solving the problems, the present invention
A cylindrical housing having two openings, an ignition means chamber connected to one opening of the cylindrical housing, and a diffuser portion having a gas discharge port connected to the other opening of the cylindrical housing And
Between the cylindrical housing and the ignition means chamber is closed by a first closing means, and between the cylindrical housing and the diffuser part is closed by a second closing means, and a pressurized gas is contained in the cylindrical housing. Is filled,
In the cylindrical housing, a rod for breaking the second closing means and opening the passage to the diffuser part during operation is in contact with the wall near the first closing means, and the tip part is the first part. 2 It is arranged in a supported state in contact with a retainer fitted in a position close to the closing means,
Since the rod tip is supported by being in contact with the retainer, the rod tip and the retainer are fixed by pressing each other, and the rod tip and the retainer are fixed to each other. The rod root portion is pressed against and fixed to the wall surface in the vicinity of the first closing means.

  During the operation of the gas generator, the first closing means is broken by the ignition means, the second closing means is broken by the rod, and the gas discharge path leading to the gas discharge port is opened. The personnel restraint device is activated. Such an operation needs to be performed reliably over 10 years, which is the useful life of the vehicle, from the viewpoint of ensuring the safety of passengers. Therefore, the rod may come off or be displaced due to externally applied vibration. Thus, the destruction of the second closing means must not be prevented.

  In the present invention, the rod tip is supported by the retainer so as to be fixed to each other, and further, the rod root and the retainer are fixed to each other so that the rod root is near the first closing means. Since the rod is supported by the distal end portion and the root portion, it is prevented from falling off or shifting.

  The contact state between the rod tip and the retainer is, for example, a state in which the rod and the retainer are pressed against each other. Specifically, the rod is pressing the retainer surface or the rod is stuck into the retainer. Can be in a state. In other words, the retainer is disposed so as to press the rod against the wall surface in the vicinity of the first closing means, and conversely, the rod is disposed so as to press the retainer (however, the retainer does not move in response to the pressure by the rod in the housing). , A part of which is in contact with and fixed to the inner surface of the housing).

  Before operation, the rod tip is disposed at a distance from the second closing means. During operation, the rod breaks the retainer in contact and advances straight, so the second closing means. Is cleaved. Thus, since an initial speed | rate when a rod contacts the 2nd obstruction | occlusion means generate | occur | produces a space | interval between 2nd obstruction | occlusion means, a 2nd obstruction | occlusion means becomes easy to be cleaved.

  The cylindrical housing has a cylindrical outer shape, but the position of the two openings is not limited, and the two openings may be provided at both ends, or may be provided on the peripheral surface, You may be provided in the edge part and the surrounding surface.

  A known electric igniter can be used as the igniting means, and a known transfer agent or gas generating agent can be used in combination with the electric igniter as the igniting means, if necessary.

  The closing means only needs to be able to withstand the pressure in the cylindrical housing and be kept in an airtight state, and a rupturable plate made of a disc such as stainless steel used in a hybrid inflator can be used.

  The retainer may be any one as long as it can be disposed in the cylindrical housing and can support the tip of the rod. For example, an elastic annular retainer that matches the internal shape of the cylindrical housing can be used.

  The annular retainer is preferably provided with a fragile portion at a portion in contact with the rod tip so that the portion that holds the rod tip with a smaller force can be reliably destroyed during operation. The weak part is a part that is thinner than other parts, a part where a groove is formed or cut, a projection (claw), a hole, etc., and when a force is applied, deformation, cleavage, The rod is allowed to move to the second closing member by breaking or the like.

  The rod may have a uniform diameter, may have a partially different diameter, or may gradually decrease in diameter from the root to the tip. The rod cross section can be circular, polygonal, or the like. The rod tip is preferably pointed in the shape of an arrowhead so that the second closing means is easily destroyed, but may be rounded or flat.

The present invention provides other means for solving the problems,
The retainer has at least one hole or recess;
The rod tip is inserted into the hole or recess of the retainer, so that the rod tip and the retainer are pressed and fixed to each other, and the rod tip and the retainer are fixed to each other. The gas generator for a personnel restraint device according to claim 1, wherein the rod root portion is pressed and fixed to a wall surface in the vicinity of the first closing means.

  The rod tip is inserted into contact with a hole (through hole) or a recess (a recess with side and bottom surfaces) of the retainer so that the rod tip and the retainer are pressed against each other and fixed. . The size of the hole or recess of the retainer is set so that the rod can be prevented from moving in the direction of the second closing means before the operation. It is preferable to provide a weak portion around the hole, and the concave portion preferably has the bottom surface itself or the bottom surface and the side surface itself as a weak portion. From the viewpoint of further reducing the breaking energy, a hole is preferable.

The present invention provides other means for solving the problems,
The rod has a shaft portion and a tip portion, and the rod tip portion has a reduced diameter portion whose diameter is smaller than that of the rod shaft portion;
The rod is inserted into the hole or recess of the retainer so that only the reduced diameter portion protrudes toward the diffuser portion, and the remaining portion presses the hole or recess of the retainer, The retainer is pressed and fixed to each other, and the rod tip and the retainer are fixed to each other so that the rod root is pressed and fixed to the wall surface in the vicinity of the first closing means. Item 3. A gas generator for a personnel restraint device according to Item 1 or 2.

  The tip reduced diameter portion can be conical, arrowhead-shaped, rod-shaped, or the like. Such a tip diameter-reduced portion (a portion whose diameter is smaller than the remaining portion; a portion having a larger diameter of the remaining portion is referred to as a large-diameter portion) is provided at the rod tip portion, and the tip diameter-reduced portion is provided in the hole or recess of the retainer. Is inserted, and the hole or recess is pressed around the large-diameter portion, so that the fixing strength of the rod tip and the retainer is increased.

  A step may be provided in the large diameter portion of the rod, and when the tip reduced diameter portion is inserted into the hole or the recess, the periphery of the hole or the recess may be pressed by the step surface. At this time, the portion that contacts the stepped surface can be a weakened portion.

  In another aspect of the present invention, the retainer is formed of an annular frame portion, a plurality of rod-like support portions extending from the peripheral edge on one end side of the annular frame portion, and the plurality of support portions. Furthermore, it consists of a center support part which has a hole or a recessed part, The surrounding surface of the said annular frame part is contacting the inner wall face of a cylindrical housing, The personnel restraint apparatus in any one of Claims 1-3 A gas generator is provided.

The present invention provides other means for solving the problems,
A cylindrical housing having two openings, an ignition means chamber connected to one opening of the cylindrical housing, and a diffuser portion having a gas discharge port connected to the other opening of the cylindrical housing And
A first passage between the cylindrical housing and the ignition means chamber is closed by a first closing means, and a second passage formed between the cylindrical housing and the diffuser portion is closed by a second closing means. The cylindrical housing is filled with pressurized gas,
In the cylindrical housing, a rod for breaking the second closing means and opening the passage to the diffuser part during operation is in contact with the wall near the first closing means, and the tip part is the first part. 2 It is arranged in a supported state in contact with a retainer fitted in a position close to the closing means,
The retainer includes an annular frame portion that contacts the inner peripheral surface of the cylindrical housing, a central support portion that contacts the tip end portion of the rod, and a rod-shaped support portion that connects the annular frame portion and the central support portion. ,
In a state where the rod is in contact with the retainer, the rod tip and the retainer are pressed against each other by elastic deformation of at least one of the annular frame, the central support, and the rod-shaped support. And the rod tip and the retainer are fixed to each other so that the rod root is pressed against the wall near the first closing means and is fixed. Provide a bowl.

  The present invention prevents the rod from coming off or displaced due to vibration from the outside and preventing the destruction of the second closing means, and when the rod tip is fixed by the retainer, The rod tip is pressed toward the first closing means by the elastic force accompanying the elastic deformation of the retainer.

  Since the retainer has an opening portion surrounded by the annular frame portion, the central support portion, and the rod-like support portion, an elastic force is easily generated by the central support portion, the rod-like support portion, and the annular frame portion. Due to this elastic force, at least one of the annular frame portion, the central support portion, and the rod-like support portion is bent toward the second closing member inside the cylindrical housing, and the reaction force causes the rod to move toward the first closing means side. Pressed. By using such a retainer, the rod can be easily fixed by using an elastic force by inserting into the cylindrical housing or press-fitting into the cylindrical housing. Moreover, since the retainer has the said opening part, it can be reduced in weight.

  In addition, as long as the effect of this invention is achieved, the center support part does not need to be formed in the center part of a retainer, and the rod-shaped support part does not need to have the constant thickness and thickness.

  According to the present invention, as another means for solving the problem, the central support portion has at least one hole or recess, and the rod tip portion is inserted into the hole or recess of the center support portion. The rod tip portion and the retainer are fixed by being pressed against each other, and the rod tip portion and the retainer are fixed to each other so that the rod root portion is in the vicinity of the first closing means. The gas generator for a personnel restraint device according to claim 5, wherein the gas generator is pressed against a wall surface and fixed.

  The rod tip and the retainer are pressed against each other by the rod tip being inserted into and in contact with a hole (through hole) or a recess (a recess with side and bottom surfaces) formed in the central support. It is fixed. The size of the hole or recess of the retainer is set so that the rod can be prevented from moving in the direction of the second closing means before the operation. It is preferable to provide a weak portion around the hole, and the concave portion preferably has the bottom surface itself or the bottom surface and the side surface itself as a weak portion. From the viewpoint of further reducing the breaking energy, a hole is preferable.

  As another means for solving the problem, the present invention provides a total opening area of an opening portion surrounded by the central support portion, the annular frame portion, and the rod-like support portion. The gas generator for a personnel restraint device according to claim 5 or 6, wherein the gas generator is larger than an area and a cross-sectional area of the second passage.

Since the retainer may be deformed when the rod penetrates during operation, it is difficult to strictly manage the area of the opening formed in the retainer. However, the gas outlet of the diffuser and the second gas passage are not deformed by the retainer,
The amount of exhaust gas can be adjusted by changing the diameter and number of exhaust ports and the diameter of the passage. Therefore, by setting the total opening area of the gas discharge ports formed in the diffuser and the cross-sectional area of the second passage to be smaller than the area of the opening portion of the retainer, the amount of exhaust gas is adjusted accordingly. Note that the total opening area of the gas discharge ports formed in the diffuser and the cross-sectional area of the second passage may be reduced.

  In the gas generator of the present invention, each is fixed by being pressed against each other with a simple structure comprising a combination of a rod and a retainer. For this reason, the position of a rod or a retainer does not shift | deviate or drop by the vibration applied from the outside.

(1) Gas generator of FIGS. 1 to 3 FIG. 1 is a longitudinal sectional view of a gas generator 10 for an airbag, FIG. 2 is a perspective view of the retainer shown in FIG. 1, and FIG. It is a perspective view of a retainer of another form. The gas generator shown in FIG. 1 is a stored type that uses pressurized gas as inflation means for an airbag.

  The cylindrical housing 20 has two openings on both ends, and has an ignition means chamber 30 connected to the opening on one end side, and a diffuser section 40 connected to the opening on the other end side. is doing. These are made of stainless steel or aluminum, and are fixed by welding at the respective joints.

  The interior space 22 of the cylindrical housing 20 is kept airtight and is filled with a simple substance such as argon, helium, nitrogen, or a mixed gas thereof (filling pressure is about 35,000 to 70,000 kPa). The pressurized gas preferably has a sound velocity of 400 m / sec or more at 0 ° C. and 1 atm (101.325 kPa). The pressurized gas is filled from the filling hole before being closed by the pin 23 and then sealed by welding the pin 23 and the cylindrical housing 20 together.

  The ignition means chamber 30 has an outer shell formed by an ignition means chamber housing 32. Inside the ignition means chamber housing 32, an electric igniter 36 provided with an igniting agent is accommodated. The igniter 36 is connected to a vehicle power supply circuit via a connector and a lead wire (both not shown). As the igniter 36, an igniter containing 260 mg of an ignition agent mainly composed of zirconium and potassium perchlorate is used.

  The first passage 37 between the cylindrical housing 20 (internal space 22) and the ignition means chamber 30 is closed by a stainless steel first rupturable plate 38, and the inside of the ignition means chamber 30 is at normal pressure. . The peripheral edge of the first rupturable plate 38 is welded and fixed to a first annular stepped surface 33 provided on the inner surface of the ignition means chamber housing 32.

The diffuser section 40 has an outer shell formed by a diffuser housing 42, and the diffuser housing 42 is provided with a plurality of gas discharge ports 46 that discharge pressurized gas to the outside. In the gas generator of FIG. 1, 30 gas discharge ports 46 having a diameter of 1.5 mm are formed (total opening area 53 mm ² ).

The second passage 44 between the cylindrical housing 20 (internal space 22) and the diffuser portion 40 is closed with a second rupturable plate 48 made of stainless steel, and the inside of the diffuser portion 40 is at normal pressure. The peripheral edge of the second rupturable plate 48 is fixed to the diffuser housing 42 by welding. The diameter of the second passage (indicated by A in FIG. 1) is 8 mm (the second passage has a cross-sectional area of 50 mm ² ). In order to cleave the second rupturable plate 48, the cylindrical housing 20 ( A rod 24 is arranged in the internal space 22).

  A retainer 50 is disposed in a portion near the diffuser portion 40 in the cylindrical housing 20.

  The retainer 50 shown in FIG. 2 includes an annular frame portion 51 having a peripheral surface portion 52 and an annular surface portion 53, a plurality of rod-like support portions 54a, 54b, 54c, 54d extending from the annular surface portion 52 to the center, and rod-like support portions. It consists of the center support part 55 which has the hole (through-hole) 56 formed by connecting with 54a-54d. The retainer 50 is made of a metal such as stainless steel or aluminum, or a synthetic resin, and has elasticity.

The retainer 50 has four openings 59 surrounded by an annular frame portion 51 (annular surface portion 53), a central support portion 55, and rod-like support portions 54a, 54b, 54c, and 54d. The total opening area of the four openings 59 is 60 mm ² .

  Since the diameter of the hole 56 is smaller than the return part 24d of the rod 24, the movement of the rod 24 in the axial direction is prevented before the operation. The center support part 55 becomes a weak part, and is more easily destroyed than other parts.

  The retainer 50 is fitted into the cylindrical housing 20 (not press-fitted), or at least a part of the outer diameter of the peripheral surface portion 52 is made slightly larger than the inner diameter of the cylindrical housing 20, thereby The housing 20 is weakly press-fitted. It is preferable to press-fit the retainer 50 weakly because the retainer 50 does not move during assembly, so that workability is good.

  In the present invention, the combination of the rod 24 and the retainer 50 is fixed by pressing each other. Therefore, even in the case of press-fitting, the retainer is press-fitted in a known gas generator. And the fixing strength may be small.

  The peripheral portion 51 a of the retainer 50 is in contact with the diffuser housing 42, and the peripheral surface portion 52 is in contact with the inner wall surface 21 of the cylindrical housing 20. The center of the hole 56 and the center of the second rupturable plate 48 face each other. Thereby, even if force is added, the retainer 50 does not move toward the second rupturable plate 48 but can press the rod 24 toward the first rupturable plate 38.

  In the gas generator of FIG. 1, the rod-like support portion 54 a or the like, the center support portion 55, or the annular frame portion 51 bends toward the second rupturable plate 48 when it is disposed inside the cylindrical housing 20 in combination with the rod 24. To be deformed. Since the retainer 50 itself has elasticity, the rod 24 is pressed toward the first rupturable plate 38 by the elastic force due to the deformation of the rod-like support portion 54 a or the like, the center support portion 55, or the annular frame portion 51. Yes.

  The retainer 50A shown in FIG. 3 is the same as the retainer 50 of FIG. 2 in terms of the basic shape and the fixing mechanism of the rod 24, but differs in that it has three claws 57 protruding inwardly into the hole 56. ing. The diameter of the hole 56 where the claw 57 is not present is larger than the maximum diameter portion (return portion 24d) of the rod 24, but the diameter including the claw 57 is smaller than the return portion 24d. The claw 57 prevents the rod 24 from moving in the axial direction.

  The rod 24 is composed of a disk portion (root portion) 24a, a shaft portion 24b, and an arrowhead portion (tip diameter-reduced portion) 24c. The respective portions are integrated and are made of metal such as stainless steel or aluminum.

  The arrowhead part 24c of the rod is such that the diameter of the return part 24d is larger than the diameter of the hole 56 of the retainer, and only a part thereof is inserted into the hole 56 without a gap (in a state of being tightly inserted), It protrudes toward the second rupturable plate 48 side. The tip portion of the arrowhead portion 24 c faces the center of the second rupturable plate 48 with a gap.

  The disc portion 24 a of the rod is in contact with a second annular step surface 34 provided on the inner surface of the ignition means chamber housing 32. In FIG. 1, the first rupturable plate 38 and the disc portion 24 a are separate members, but the disc portion 24 a and the first rupturable plate 38 may be formed integrally, and the disc portion 24 a further includes the first rupturable plate 38. It may be something that doubles as well.

  The retainer 50 is fitted (or press-fitted) in contact with the inner wall surface 21 of the cylindrical housing 20 and the diffuser housing 42, and the arrowhead 24c of the rod 24 is tightly attached to the retainer hole 56 shown in FIG. Since the rod 24 and the retainer 50 are pressed against each other, the second annular step surface 34 of the ignition means chamber housing 32 is pressed by the disc portion 24a of the rod.

  Thus, since the rod 24 and the retainer 50 are sandwiched between the ignition means chamber housing 32 and the diffuser housing 42, both the retainer 50 and the rod 24 are fixed at predetermined positions. Further, not only rattling of the rod 24 is prevented by vibrations from the outside, but also rattling and dropping of the retainer 50 itself are prevented.

  When the retainer 50 is fitted into the cylindrical housing 20 without being press-fit or when the retainer 50 is press-fit, even when the fixing strength by press-fitting is small, the rod 24 and the retainer 50 are combined as described above. As a result, the same fixing strength as that when strongly press-fitted can be obtained. Of course, it may be strongly pressed in the same manner as when the retainer is press-fitted in a known gas generator, in which case the press-fitting strength is further increased.

  Next, an operation when the gas generator 10 shown in FIG. 1 and FIG. 2 or FIG. 3 is incorporated in an automobile airbag system will be described. In the gas generator 10, the igniter 36 for pulling out the lead wire and the gas discharge port 46 for attaching the airbag are located on the opposite side, so that the lead wire does not get in the way when the airbag is attached.

  When the automobile collides and receives an impact, the first rupturable plate 38 is destroyed and the first passage 37 is opened by the shock wave generated by the operation signal from the control unit and the igniter 36 being activated and ignited. . The shock wave that destroyed the first passage 37 subsequently collides with the rod disk portion 24a and is pressed.

  As a result, the rod 24 moves in the axial direction, and in the retainer 50 shown in FIG. 2, the arrowhead portion 24 c inserted into the hole 56 breaks the central support portion 55 and goes straight and collides with the second rupturable plate 48. To do. In the retainer 50 </ b> A shown in FIG. 3, the arrowhead part 24 c inserted into the hole 56 breaks the three claws 57 and goes straight and collides with the second rupturable plate 48. Then, the second rupturable plate 48 is broken by the collision of the arrowhead 24c, the second passage 44 is opened, the pressurized gas is discharged from the gas discharge port 46, and the airbag is inflated. In the case of FIG. 2, the hole 56 itself is a fragile portion, and the tip of the arrowhead 24 c penetrates before the operation, so that the rod 24 is easily moved by the operation of the igniter 26.

  Note that the rod disk portion 24 a may be fixed so that the outer peripheral surface of the rod disk portion 24 a comes into contact with the inner peripheral surface of the cylindrical housing 20 and is pressed against the ignition means chamber housing 32 by the retainer 50. In this case, the rod 24 is positioned in the radial direction by contact (not pressure contact) of the outer peripheral surface of the rod disk portion 24a and the inner peripheral surface of the cylindrical housing 20, and the axial fixing of the rod 24 is performed by the retainer. 50 and ignition means chamber housing 32.

(2) Gas Generator of FIG. 4 FIG. 4 is a perspective view of the gas generator of FIG. 1 modified in association with the shape of the rod tip and the hole shape of the retainer.

The arrowhead 24c of the rod 24A has a smaller diameter than the shaft 24b, and a hanging wall surface 24e is provided between the shaft 24b and the arrowhead 24c.
The center support portion 55 of the retainer 50 </ b> B is provided with a hole 56 and a deterrent surface 55 a that is a fragile portion. The hole 56 has the same shape as the arrowhead part 24c, and the arrowhead part 24c can be inserted tightly.
When the arrowhead portion 24c of the rod 24A is inserted into the hole 56 of the retainer 50, the vertical wall surface 24e is brought into contact with the restraining surface 55a, so that no further insertion is possible. Since the vertical wall surface 24e is brought into contact with the restraining surface 55a in this way, the movement of the rod 24A in the axial direction is prevented before operation. However, during operation, the restraining surface 55a is broken and the rod 24A is pivoted. The second rupturable plate 48 shown in FIG. 1 is destroyed. The vertical wall surface 24e and the restraining surface 55a are brought into contact with each other, so that the rod-like support portion 54a or the like, the central support portion 55, or the annular frame portion 51 bends, and an elastic force is generated to cause the rod 24 to be moved to the first rupturable plate 38. Pressing to the side is the same as in the above embodiment.

(3) Gas generator of FIG. 5 FIG. 5 is a longitudinal sectional view of a gas generator for an air bag. The gas generator for an air bag in FIG. 5 is a hybrid type that uses a combustion gas of a gas generating agent and a pressurized gas in combination as an air bag inflating means.

  The cylindrical housing 120 has two openings on one end side and a peripheral surface, an ignition means chamber 130 connected to the opening on one end side, and a diffuser portion 140 connected to the opening on the peripheral surface. have. These are made of stainless steel or aluminum, and are fixed by welding at the respective joints.

  The interior space 122 of the cylindrical housing 120 is kept airtight, and is filled with a simple substance such as argon, helium, nitrogen, or a mixed gas thereof (filling pressure is about 35,000 to 70,000 kPa). The pressurized gas preferably has a sound velocity of 400 m / sec or more at 0 ° C. and 1 atm (101.325 kPa). The pressurized gas is filled from a filling hole before being closed with a pin (not shown), and then sealed by welding the pin and the cylindrical housing 120 together.

  The ignition means chamber (also having a function as a combustion chamber) 130 has an outer shell formed by an ignition means chamber housing 132. Inside the ignition means chamber housing 132, an electric igniter 136 including a igniting agent and a gas generating agent 137 are accommodated. The igniter 136 is connected to a vehicle power supply circuit via a connector and a lead wire (both not shown).

  On a part of the peripheral surface of the ignition means chamber housing 132, a V-shaped notch 135 is formed in a broken line shape so that the planar shape is circular, and an inner portion surrounded by the V-shaped notch 135 becomes a fragile portion, A first rupturable plate 138 is formed. Therefore, before the operation, the cylindrical housing 120 (internal space 122) and the ignition means chamber 130 are not communicated with each other, and are communicated by breaking the first rupturable plate 138 during the operation.

  The diffuser unit 140 has an outer shell formed by a diffuser housing 142, and the diffuser housing 142 is provided with a plurality of gas discharge ports 146 that discharge pressurized gas to the outside.

  The space between the cylindrical housing 120 (internal space 122) and the diffuser part 140 is closed by a second rupturable plate 148 made of stainless steel, and the inside of the diffuser part 140 is at normal pressure. The peripheral edge of the second rupturable plate 148 is welded to the step surface 151 inside the diffuser housing 142.

  A retainer 50 is disposed in the diffuser unit 140. The retainer 50 is the same as that of FIG.

  The retainer 50 is fitted into the diffuser housing 142 (not press-fitted), or at least a part of the outer diameter of the peripheral surface portion 52 is made slightly larger than the inner diameter of the diffuser housing 142, thereby causing the diffuser housing 142. It is press-fitted weakly.

  In the retainer 50, the peripheral edge portion 51 a is in contact with the step surface 151, and the peripheral surface portion 52 is in contact with the inner wall surface 143 of the diffuser housing 142. The center of the hole 56 and the center of the second rupturable plate 148 face each other.

  A rod 124 for cleaving the second rupturable plate 148 is disposed in the cylindrical housing 120. The rod 124 is composed of a columnar root reduced diameter portion 124a, a shaft portion 124b, and a cylindrical tip reduced diameter portion 124c. The respective portions are integrated, and are made of metal such as stainless steel or aluminum.

  Since the diameter of the rod diameter reducing portion 124 c of the rod is large enough to be inserted into the retainer hole 56, and the diameter of the shaft portion 124 b of the rod is larger than the diameter of the retainer hole 56, only the diameter reducing portion 124 c of the rod is in the hole 56. Inserted and protruded toward the second rupturable plate 148, the end surface of the shaft portion 124 b presses the central support portion (fragile portion) 55. The tip portion of the tip diameter-reduced portion 124 c faces the center of the second rupturable plate 148 with a gap.

  The fundamentally reduced diameter portion 124 a of the rod is tightly fitted in a hole (not penetrating) provided in the center of the first rupturable plate 138 of the ignition means chamber housing 132.

  The retainer 50 is fitted (or press-fitted) in contact with the inner wall surface of the diffuser housing 142, and the tip diameter-reduced portion 124c of the rod 124 is inserted into the hole 56 of the retainer shown in FIG. Part) 55 is pressed by the end face of the shaft part 124b.

  In this manner, the retainer 50 and the rod 124 are sandwiched between the ignition means chamber housing 132 and the diffuser housing 142, so that both the retainer 50 and the rod 124 are fixed at predetermined positions. In addition, the rattling of the rod 124 is prevented not only by vibrations from the outside, but also the rattling and dropping of the retainer 50 itself are prevented.

  Next, the operation when the gas generator 100 shown in FIGS. 5 and 2 is incorporated into an automobile airbag system will be described. In the gas generator 100, the igniter 136 for pulling out the lead wire and the gas discharge port 146 for attaching the airbag are positioned in a direction orthogonal to each other, so that the lead wire does not get in the way when the airbag is attached. .

  When the automobile collides and receives an impact, an operation signal is received from the control unit, and the igniter 136 is operated and ignited to ignite and burn the gas generating agent 137 to generate combustion gas. As a result of the combustion gas being generated, the pressure in the ignition means chamber housing 130 is increased, so that the first rupturable plate 138 is destroyed and the entire rod 124 is pressed.

  Then, the rod 124 moves in the axial direction, breaks the central support portion 55 of the retainer 50 and advances straight, and the tip diameter-reduced portion 124 c collides with the second rupturable plate 148. Then, the second rupturable plate 148 is broken by the collision of the tip diameter-reduced portion 124c, the combustion gas and the pressurized gas are discharged from the gas discharge port 146, and the airbag is inflated.

(4) Gas Generator in FIGS. 6 and 7 FIG. 6 is a longitudinal sectional view of the gas generator 10 for an airbag, and FIG. 7 is a perspective view of the retainer shown in FIG. The gas generator shown in FIG. 6 is the same as the gas generator 10 shown in FIG. 1 except that the shape of the tip of the rod 24B and the shape of the hole 56 of the retainer 50C are different. Stored type using gas.

  The rod 24B has a uniform diameter as a whole, and the tip surface 24f is a flat surface. The retainer 50 </ b> C has a raised peripheral edge of the hole 56, and has an inward flange portion (becomes a fragile portion) 58. The peripheral edge portion of the front end surface 24f is in pressure contact with the inward flange portion 58.

  The retainer 50C is fitted (or press-fitted) in contact with the inner wall surface 21 of the cylindrical housing 20 and the diffuser housing 42, and the distal end surface 24f of the rod 24 is pressed against the inward flange portion 58 of the retainer. As shown in FIG. 1, the opposite end of the rod 24 presses the second annular step surface 34 of the ignition means chamber housing 32.

  Thus, since the rod 24 and the retainer 50 are sandwiched between the ignition means chamber housing 32 and the diffuser housing 42, both the rod 24 and the retainer 50 are fixed at predetermined positions. Further, not only rattling of the rod 24 is prevented by vibrations from the outside, but also rattling and dropping of the retainer 50 itself are prevented.

The longitudinal cross-sectional view of the gas generator for airbags. The perspective view of the retainer of FIG. The perspective view of the retainer of another form. The perspective view of the rod and retainer of another form. The longitudinal cross-sectional view of the gas generator for airbags of another form. The longitudinal fragmentary sectional view of the gas generator for airbags of another form. The perspective view of the retainer of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Gas generator 20 Cylindrical housing 24 Rod 30 Ignition means chamber 32 Ignition means chamber housing 38 1st rupturable plate 40 Diffuser part 42 Diffuser housing 46 Gas discharge port 48 2nd rupturable plate 50 Retainer

Claims (7)

A cylindrical housing having two openings, an ignition means chamber connected to one opening of the cylindrical housing, and a diffuser portion having a gas discharge port connected to the other opening of the cylindrical housing And
Between the cylindrical housing and the ignition means chamber is closed by a first closing means, and between the cylindrical housing and the diffuser part is closed by a second closing means, and a pressurized gas is contained in the cylindrical housing. Is filled,
In the cylindrical housing, a rod for breaking the second closing means and opening the passage to the diffuser part during operation is in contact with the wall near the first closing means, and the tip part is the first part. 2 It is arranged in a supported state in contact with a retainer fitted in a position close to the closing means,
Since the rod tip is supported by being in contact with the retainer, the rod tip and the retainer are fixed by pressing each other, and the rod tip and the retainer are fixed to each other. A gas generator for a person restraining device for a vehicle, wherein the rod root portion is pressed and fixed to a wall surface in the vicinity of the first closing means. The retainer has at least one hole or recess;
The rod tip is inserted into the hole or recess of the retainer, so that the rod tip and the retainer are pressed and fixed to each other, and the rod tip and the retainer are fixed to each other. The gas generator for a personnel restraint device according to claim 1, wherein the rod root portion is pressed and fixed to a wall surface in the vicinity of the first closing means. The rod has a shaft portion and a tip portion, and the rod tip portion has a reduced diameter portion whose diameter is smaller than that of the rod shaft portion;
The rod is inserted into the hole or recess of the retainer so that only the reduced diameter portion protrudes toward the diffuser portion, and the remaining portion presses the hole or recess of the retainer, The retainer is pressed and fixed to each other, and the rod tip and the retainer are fixed to each other so that the rod root is pressed and fixed to the wall surface in the vicinity of the first closing means. Item 3. A gas generator for a personnel restraint device according to item 1 or 2.   The retainer includes an annular frame portion, a plurality of rod-like support portions extending from the peripheral edge on one end side of the annular frame portion, and a central support portion having a hole or a recess formed by the plurality of support portions. The gas generator for a personnel restraint device according to any one of claims 1 to 3, wherein a peripheral surface of the annular frame portion is in contact with an inner wall surface of the cylindrical housing. A cylindrical housing having two openings, an ignition means chamber connected to one opening of the cylindrical housing, and a diffuser portion having a gas discharge port connected to the other opening of the cylindrical housing And
A first passage between the cylindrical housing and the ignition means chamber is closed by a first closing means, and a second passage formed between the cylindrical housing and the diffuser portion is closed by a second closing means. The cylindrical housing is filled with pressurized gas,
In the cylindrical housing, a rod for breaking the second closing means and opening the passage to the diffuser part during operation is in contact with the wall near the first closing means, and the tip part is the first part. 2 It is arranged in a supported state in contact with a retainer fitted in a position close to the closing means,
The retainer includes an annular frame portion that contacts the inner peripheral surface of the cylindrical housing, a central support portion that contacts the tip end portion of the rod, and a rod-shaped support portion that connects the annular frame portion and the central support portion. ,
In a state where the rod is in contact with the retainer, the rod tip and the retainer are pressed against each other by elastic deformation of at least one of the annular frame, the central support, and the rod-shaped support. And the rod tip and the retainer are fixed to each other so that the rod root is pressed against the wall near the first closing means and is fixed. vessel.   The center support portion has at least one hole or recess, and the rod tip portion is inserted into the hole or recess of the center support portion, so that the rod tip portion and the retainer are The rod root portion and the retainer are fixed to each other by being pressed against each other, and the rod root portion is pressed and fixed to the wall surface in the vicinity of the first closing means. 5. A gas generator for a personnel restraint device according to 5. The total opening area of the opening portion surrounded by the central support portion, the annular frame portion, and the rod-shaped support portion is larger than the total opening area of the gas discharge ports formed in the diffuser and the cross-sectional area of the second passage. The gas generator for personnel restraint devices according to claim 5 or 6.

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