JP2012091110A - Gas generator and holder for the gas generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas generator which withstands high pressure and is superior in the mountability on a vehicle or the like.SOLUTION: The gas generator 1A includes a cup 30, an igniter 20 and a holder 10A. The holder 10A has: a first concave part 12 which is arranged on the end face of the holder in the axial direction on the side, which faces the cup 30, and is used for receiving/holding the igniter 20; a second concave part 13 which is arranged on the end face of the holder in the axial direction on the side, which does not face the cup 30, and is used for receiving/holding a connector for an external connection of the igniter 20; a division wall part 14 for dividing the first concave part 12 from the second concave part 13; and a circular groove part 15 which is arranged on the outer peripheral surface 11 of the holder and is used for receiving/holding the opening edge of the cup 30 inserted along the axial direction. The bottom surface of the circular groove part 15 is arranged on such a portion that the division wall part 14 of the holder 10A is surrounded in the radial direction. A corner part 13d of the second concave part 13 comprises a curved plane extending to both of the surfaces adjacent thereto.

Description

  The present invention relates to a gas generator and a holder for a gas generator (hereinafter, also simply referred to as “holder”) provided in the gas generator, and more particularly to a gas generator incorporated in a seat belt pretensioner device and the gas generator. The present invention relates to a gas generator holder.

  Conventionally, seat belt devices and airbag devices have been widely used from the viewpoint of protecting passengers such as automobiles. Among these, the seat belt device is equipped to prevent the occupant from being thrown out of or inside the vehicle due to an impact caused by a vehicle collision, and the occupant is restrained on the seat by wrapping the belt around the occupant's body. And fix it.

  In recent years, a seat belt device having a pretensioner function has been rapidly spread to improve an occupant protection function. The pretensioner function instantaneously winds up the slack of the seat belt caused by the thickness of clothes at the time of collision, and increases the restraining effect of the occupant. This pretensioner function is realized by the seat belt being pulled strongly by the pressure of the gas output from a gas generator called a micro gas generator (MGG).

  Examples of this type of gas generator include those disclosed in Japanese Unexamined Patent Application Publication No. 2008-37389 (Patent Document 1) and those disclosed in Japanese Unexamined Patent Application Publication No. 2001-88653 (Patent Document 2). The gas generator disclosed in Patent Documents 1 and 2 includes a bottomed substantially cylindrical cup loaded with a gas generating agent that generates gas by combustion, an igniter for burning the gas generating agent, It is assembled to the cup on the same axis so as to close the open end of the cup, and includes a substantially cylindrical holder formed by holding an igniter so as to face the gas generating agent.

  Here, since the holder holds the igniter as described above and is used with the cup assembled, the first end face in the axial direction of the holder receives and holds the igniter. One recess and an annular groove for receiving and holding the opening edge of the cup are provided. Further, since the connector for connecting the igniter to the outside needs to be detachably attached to the holder, the other axial end surface of the holder has a second recess for receiving and holding the connector. Provided.

JP 2008-37389 A JP 2001-88653 A

  In the above-described gas generator, there is a strong demand for improvement in mountability to vehicles and the like, and the reduction in size and weight is an important issue. Here, the above-mentioned holder made of a metal material is a component that accounts for a high proportion of the total weight among the components constituting the gas generator. Therefore, the holder can be reduced in size and weight by changing the material, shape, thickness, etc. Attempts have been made to make it easier.

  However, since the holder is also a component that receives a high pressure during the operation of the gas generator, its mechanical strength (that is, pressure resistance) needs to be ensured to be high. For example, when the gas generator is activated, the gas generated in the gas generator is introduced into the working space of the pretensioner module incorporated in the seat belt device. Becomes very high pressure, and the high pressure is applied to the holder. Here, if the mechanical strength of the holder is insufficient, the holder cannot withstand the high pressure, and the holder is damaged. As a result, the gas leaks from the damaged portion. It will be.

  As described above, in the above-described gas generator, it is indispensable to reduce the size and weight in order to improve the mountability to a vehicle or the like while ensuring high pressure resistance performance to realize stable operation. ing.

  Therefore, the present invention has been made to solve the above-described problems, and provides a gas generator having high pressure resistance and excellent mountability to a vehicle and the like, and a gas generator holder provided therein. With the goal.

  A gas generator according to the present invention includes a bottomed substantially cylindrical cup loaded with a gas generating agent that generates gas by combustion, and an ignition agent that burns the gas generating agent by igniting during operation. An igniter including a terminal pin connected to the igniter to ignite the contained igniter and the ignition agent, and is assembled to the cup coaxially so as to close the open end of the cup, A substantially cylindrical holder configured to hold the igniter so that the ignition unit faces the gas generating agent. The holder is provided on an axial end surface on the side facing the cup, and is provided on a first recess for receiving and holding the igniter, and on an axial end surface on the side not facing the cup, and the terminal pin is disposed. And defining a second recess for receiving and holding a connector for external connection of the igniter via the terminal pin, a bottom surface of the first recess, and a bottom surface of the second recess. A partition wall that partitions the first recess and the second recess, and an annular groove that is provided on the outer peripheral surface and receives and holds the opening edge of the cup inserted along the axial direction. The bottom surface of the annular groove is provided in a portion surrounding the partition of the holder in the radial direction. The corner located between the bottom surface of the second recess and the peripheral surface of the second recess is formed by a curved surface that is continuous with any of these adjacent surfaces.

  In the gas generator based on the said invention, it is preferable that the curvature radius of the said curved surface along the cut surface at the time of cut | disconnecting the said holder along the plane containing an axis line is 0.5 mm or more.

  In the gas generator based on the said invention, it is preferable that the surrounding surface of the said 2nd recessed part is located inside the inner peripheral surface of the said annular groove part in radial direction.

  In the gas generator according to the present invention, the corner portion located between the bottom surface of the annular groove portion and the inner peripheral surface of the annular groove portion is a curved surface that is continuous with any of these adjacent surfaces. It is preferable to be configured.

  In the gas generator based on the said invention, it is preferable that the flange part extended toward the outer side is provided in the opening edge of the said cup. In that case, the annular flange portion, which is a portion defining the outer peripheral surface of the annular groove portion, is caulked inward so as to cover the flange portion, whereby the opening edge of the cup is received and held by the annular groove portion. It is preferable that

  The holder for a gas generator according to the present invention has a substantially columnar shape that holds an igniter for burning a gas generating agent and is assembled with a bottomed substantially cylindrical cup loaded with the gas generating agent. A first recess for receiving and holding the igniter and an axial end surface on the side where the cup is not assembled, provided on the axial end surface on the side where the cup is assembled, Defining a second recess for receiving and holding a connector for external connection of the igniter via the terminal pin, a bottom surface of the first recess, and a bottom surface of the second recess; The partition part which partitions the said 1st recessed part and the said 2nd recessed part, and the annular groove part which is provided in an outer peripheral surface and accepts and hold | maintains the opening edge of the cup inserted along an axial direction. The bottom surface of the annular groove is provided in a portion surrounding the partition wall in the radial direction. The corner located between the bottom surface of the second recess and the peripheral surface of the second recess is formed by a curved surface that is continuous with any of these adjacent surfaces.

  In the gas generator holder according to the present invention, it is preferable that the radius of curvature of the curved surface along the cut surface when cut along a plane including the axis is 0.5 mm or more.

  In the gas generator holder according to the present invention, it is preferable that the peripheral surface of the second recess is located inside the inner peripheral surface of the annular groove in the radial direction.

  In the gas generator holder according to the present invention, the corner portion located between the bottom surface of the annular groove portion and the inner peripheral surface of the annular groove portion is a curved surface continuous with any of these adjacent surfaces. It is preferable to be configured.

  ADVANTAGE OF THE INVENTION According to this invention, it can be set as the gas generator excellent in mountability to a vehicle etc. with high pressure | voltage resistance, and the holder for gas generators comprised in this.

It is a schematic cross section of a gas generator in an embodiment of the present invention. It is a schematic cross section before the assembly | attachment of the holder for gas generators in embodiment of this invention. It is an expansion schematic cross section of the area | region III shown in FIG. 1 of the gas generator in embodiment of this invention. It is a principal part expansion schematic cross section of the gas generator which concerns on a comparative example. It is a principal part expansion schematic sectional drawing of the gas generator which concerns on the modification based on embodiment of this invention. It is a table | surface which shows the result of the verification test which verified the pressure | voltage resistant performance of the gas generator which concerns on a comparative example and Examples 1,2. It is a cross-sectional photograph after the shear fracture of the holder for gas generators concerning a comparative example. It is a cross-sectional photograph after the shear fracture of the holder for gas generators concerning Example 1. FIG. It is a cross-sectional photograph after the shear fracture of the holder for gas generators concerning Example 2. FIG.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In addition, the gas generator in embodiment shown below is a micro gas generator used by being assembled | attached to the pretensioner module integrated in a seatbelt apparatus.

  FIG. 1 is a schematic cross-sectional view of a gas generator according to an embodiment of the present invention, and FIG. 2 is a schematic cross-sectional view before assembly of a gas generator holder according to the present embodiment. First, with reference to these FIG. 1 and FIG. 2, the structure of the gas generator in this Embodiment and the holder for gas generators provided in this is demonstrated.

  As shown in FIG. 1, the gas generator 1 </ b> A in the present embodiment mainly includes a holder 10 </ b> A, an igniter 20, a cup 30, and a gas generating agent 35. Here, the igniter 20 is held by the holder 10 </ b> A, and the cup 30 is assembled to the holder 10 </ b> A so as to cover the igniter 20. The holder 10A and the cup 30 constitute a housing that becomes an outer shell of the gas generator 1A by combining them. The gas generating agent 35 loaded in the cup 30 is accommodated in a space defined by the holder 10A, the igniter 20 and the cup 30 after assembly. The igniter 20 is also referred to as a squib.

  As shown in FIG. 1, the igniter 20 is a device for generating a flame. The igniter 21 in which an igniting agent that burns the gas generating agent 35 by igniting during operation is accommodated, and the igniting agent. It includes a pair of terminal pins 22 connected to the ignition unit 21 for ignition, and a base (header) 23 that holds the pair of terminal pins 22. More specifically, the ignition unit 21 includes a bridge wire provided so as to contact the ignition agent, and a squib cup attached to the base 23 to accommodate the ignition agent and the bridge wire inside. Both ends of the bridge line are respectively connected to the tips of a pair of terminal pins 22 held by the base 23 inside the squib cup.

  Nichrome wire or the like is generally used as the electrical bridge wire, and ZPP (zirconium / potassium perchlorate), ZWPP (zirconium / tungsten / potassium perchlorate) or the like is generally used as the igniting agent. Further, as the squib cup, a metal or plastic member is generally used. In addition, in the ignition part 21, in addition to an ignition agent, a charge transfer agent may be loaded.

  When a collision is detected, a predetermined amount of current flows through the bridge line via the terminal pin 22. When a predetermined amount of current flows through the bridge line, Joule heat is generated in the bridge line, whereby the igniting agent is ignited and combustion starts. The high-temperature flame (gas and hot particles) generated by the combustion ruptures the squib cup containing the igniting agent and ignites the gas generating agent 35. The time from when the current flows through the bridge line until the igniter 20 is activated is generally 3 milliseconds or less when the nichrome line is used as the bridge line.

  As shown in FIG. 1, the cup 30 is made of a substantially cylindrical member having a bottom with an axial end open, and a gas generating agent 35 is loaded therein. The cup 30 is also a member constituting a part of the housing, and is constituted by a molded product made of a metal material such as aluminum or aluminum alloy. For forming the cup 30, press working using a mold is generally used.

  More specifically, the cup 30 has a side wall portion 31 and a bottom wall portion 32, and a gas generating agent 35 is accommodated in an accommodation space 34 defined by the side wall portion 31 and the bottom wall portion 32. . The bottom wall portion 32 of the cup 30 is provided with a fragile portion by forming a notch (score) or the like on the surface thereof, and the fragile portion can be opened when the gas generator 1A is operated. ing. A flange portion 33 is provided at the opening edge of the cup 30 so as to extend outward from the tip of the side wall portion 31 continuously. The opening edge of the cup 30 including the flange portion 33 is a part for fixing the cup 30 to the holder 10A.

  The gas generating agent 35 is ignited by the igniter 20 and burns to generate a large amount of gas. As the gas generating agent 35, a molded product of smokeless explosive (nitrocellulose), a molded product of a non-azide composition composed of an organic nitrogen compound and an oxidizing agent, or the like is used. In recent years, attention has been focused on the use of a non-nitrocellulose-based gas generating agent that generates a very small amount of harmful substances such as carbon monoxide as the gas generating agent 35.

  As the molded body of the gas generating agent 35, various shapes such as granules, pellets, columns, disks, and the like can be used. A perforated material having a through hole (for example, a macaroni shape or a lotus root shape) can be used as the molded body of the gas generating agent 35. The optimum shape is selected according to the specifications of the pretensioner module to which the gas generator 1A is assembled. In addition to the shape, the size of the molded body of the gas generating agent 35 and the like are selected in consideration of the linear combustion rate, the pressure index, and the like. The filling amount of the gas generating agent 35 can be appropriately changed according to the specification of the pretensioner module to be assembled. However, when smokeless gunpowder is used, it should be approximately 0.2 to 2.0 g. Is common.

  As shown in FIG. 1, the holder 10 </ b> A is a member for holding the igniter 20 and the cup 30 and has a substantially cylindrical outer shape. The holder 10A is also a member that constitutes a part of the housing, and is formed of a molded product made of a metal material such as aluminum, an aluminum alloy, or an iron-based material including stainless steel. For forming the holder 10A, generally, a combination of cutting, forging using a die, drawing, pressing, or the like is used. The holder 10A is formed into a desired shape by repeated pressurization and flow by these processes. Molded.

  As shown in FIGS. 1 and 2, the holder 10 </ b> A includes a first recess 12 provided on the axial end surface on the side facing the cup 30, and a second recess provided on the axial end surface on the side not facing the cup 30. It mainly comprises a recess 13 and an annular groove 15 provided on the outer peripheral surface 11a. In addition, between the 1st recessed part 12 and the 2nd recessed part 13, the partition part 14 which partitions off these 1st recessed parts 12 and the 2nd recessed part 13 is located, The said partition part 14 is the edge of the radial direction. This part is continuous with the cylindrical part 11 that defines the outer peripheral surface 11a. In addition, the partition wall 14 is provided with a pair of through holes 14 a that communicate the first recess 12 and the second recess 13.

  The 1st recessed part 12 is a site | part for receiving and holding the igniter 20, and has the bottom face 12a and the surrounding surface 12b. Among these, the bottom surface 12 a of the first recess 12 is defined by the partition wall portion 14 described above, and the peripheral surface 12 b of the first recess 12 is a portion for caulking and fixing the igniter 20 in the cylindrical portion 11. It is defined by the annular protrusion 17.

  The second recess 13 is a part for receiving and holding a connector (not shown) for external connection of the igniter 20 via the terminal pin 22 in which the terminal pin 22 of the igniter 20 is disposed. 13a and a peripheral surface 13b. Among these, the bottom surface 13 a of the second recess 13 is defined by the partition wall 14 described above, and the peripheral surface 13 b of the second recess 13 is defined by the cylindrical portion 11. In addition, an engagement groove 13f that extends annularly along the circumferential direction is provided at a predetermined position on the circumferential surface 13b of the second recess. The engagement groove 13 f is a part for holding the connector in the second recess 13 by engaging with a protrusion provided in the connector inserted into the second recess 13.

  The annular groove portion 15 is a portion for receiving and holding the opening edge of the cup 30 inserted along the axial direction, and has a bottom surface 15a, an inner peripheral surface 15b, and an outer peripheral surface 15c. The bottom surface 15 a, the inner peripheral surface 15 b and the outer peripheral surface 15 c are all defined by the cylindrical portion 11, and the annular flange portion 16 which is a portion defining the outer peripheral surface 15 c is caulked and fixed to the opening edge of the cup 30. It is also a part to do.

  Further, a fixed portion 18 formed by projecting a part of the cylindrical portion 11 in the axial direction outward in the radial direction is provided on the outer peripheral surface 11a of the holder 10A. The fixed part 18 is a part used when the gas generator 1A is assembled to the pretensioner module, and the fixed part 18 is held in the axial direction by the fixing part provided in the pretensioner module. Thus, the gas generator 1A is assembled to the pretensioner module. The end portion of the fixed portion 18 on the cup 30 side is configured by the annular flange portion 16 described above.

  As shown in FIG. 1, the igniter 20 is configured so that the terminal pin 22 is inserted through the through hole 14 a provided in the partition wall portion 14 from the axial end surface of the holder 10 </ b> A on the side where the first recess 12 is provided. It is inserted into the first recess 12. Thereby, the base 23 of the igniter 20 is accommodated in the first recess 12 and the terminal pin 22 is disposed in the second recess 13. In this state, the tip of the annular protrusion 17 of the holder 10A is caulked toward the base 23 side of the igniter 20, whereby the igniter 20 is caulked and fixed to the holder 10A.

  Here, a seal member 28 made of an O-ring or the like is accommodated in the first recess 12 of the holder 10A in advance, and a gap generated between the holder 10A and the igniter 20 is sealed by the seal member 28. ing. More specifically, the seal member 28 is interposed between the cylindrical portion 11 and the partition wall portion 14 of the holder 10 </ b> A and the base portion 23 of the igniter 20, and this portion of the gas generator 1 </ b> A is provided by the seal member 28. The inside is hermetically sealed. As the seal member 28, a member having sufficient heat resistance and durability is preferably used. For example, a member made of EPDM which is a kind of ethylene propylene rubber is suitably used.

  Further, the igniter 20 and the upper portion of the base 23 are previously covered with a cover member 25 having a substantially cylindrical shape with a bottom, and the annular protrusion 17 of the holder 10A is ignited together with the cover member 25. The container 20 is fixed by caulking. In the bottom wall portion 25a of the cover member 25, there is a guide hole 26 for injecting a high-temperature flame generated by burning of the igniting agent accommodated in the igniter 20 of the igniter 20 toward the gas generating agent 35. Is provided. In addition, the cover member 25 is comprised with the molded article which consists of metal materials, such as iron-type material containing aluminum, aluminum alloy, stainless steel, for example.

  The cover member 25 is for preventing the squib cup from rupturing before the internal pressure of the squib cup is sufficiently increased when the igniter 20 is operated. Therefore, by providing the cover member 25, it is possible to reliably burn the ignition agent under high pressure, and as a result, it is possible to increase the combustion rate of the ignition agent and prevent the ignition delay of the gas generating agent 35. become.

  On the other hand, the opening edge of the cup 30 is inserted into the annular groove portion 15 of the holder 10A along the axial direction in a state where the gas generating agent 35 is loaded therein. Thereby, the flange part 33 provided in the opening edge of the cup 30 is arrange | positioned in the annular groove part 15, and the front-end | tip of the annular collar part 16 of the holder 10A is crimped inside so that the flange part 33 may be covered in this state. Thus, the cup 30 is caulked and fixed to the holder 10A. By this caulking, a gap generated between the holder 10A and the cup 30 is sealed, and the inside of the gas generator 1A is hermetically sealed at the portion.

  Next, with reference to FIG. 1, the operation | movement at the time of the action | operation of the gas generator in this Embodiment is demonstrated.

  When a vehicle on which the gas generator 1A according to the present embodiment is mounted collides, the collision is detected by a collision detection unit provided separately in the vehicle, and the igniter 20 is operated based on this. When the igniter 20 is actuated, the igniting agent accommodated in the igniter 21 is ignited and burned, whereby the squib cup is ruptured.

  The flame generated by the combustion of the igniting agent is ejected toward the accommodation space 34 in which the gas generating agent 35 is accommodated through the fire guide hole 26 of the cover member 25 when the squib cup is ruptured. Due to this flame, the gas generating agent 35 is ignited and burned, and a large amount of gas is generated in the accommodation space 34. Due to the combustion of the gas generating agent 35, the internal pressure of the accommodation space 34 rapidly rises, thereby opening a fragile portion provided in the bottom wall portion 32 of the cup 30, and a large amount of generated gas is generated in the gas generator 1A. It will be derived to the outside.

  Thereafter, a large amount of gas led out from the gas generator 1A is guided to the working space of the pretensioner module, thereby driving the pretensioner module, whereby the seat belt is strongly pulled in.

  As shown in FIGS. 1 and 2, in the gas generator 1 </ b> A and the holder 10 </ b> A provided therein according to the present embodiment, the annular groove portion 15 provided in the holder 10 </ b> A faces the cup 30 of the holder 10 </ b> A. Is provided at a position retracted by a predetermined distance along the axial direction from the axial end surface (that is, the tip end surface of the annular protrusion 17) toward the axial end surface on the side not facing the cup 30. More specifically, the bottom surface 15a of the annular groove 15 is provided so as to recede to a portion surrounding the partition wall 14 that partitions the first recess 12 and the second recess 13 of the holder 10A in the radial direction.

  With this configuration, in the gas generator 1A and the holder 10A provided therein according to the present embodiment, the shaft of the holder 10A on the side facing the cup 30 rather than the position where the annular groove 15 is provided. By eliminating the portion near the direction end face, the holder 10A is reduced in size and weight. Here, in the conventional gas generator, as disclosed in Patent Document 1, the annular groove portion is disposed along the axial direction on the end face side in the axial direction with respect to the partition wall portion. The configuration was not shown.

  Further, as described above, the annular flange portion 16 that defines the outer peripheral surface 15c of the annular groove portion 15 is also a portion that defines the upper end of the fixed portion 18 of the holder 10A. Retreating to the above position leads to shortening the axial length of the fixed portion 18. Here, since the reduction in the axial length of the fixed portion 18 contributes to the reduction in size and weight of the pretensioner module, the axial length of the fixed portion 18 is within a range in which the mechanical strength is ensured. It is preferable that the inner length is shorter. Therefore, the above-described configuration of the gas generator 1A and the holder 10A included in the gas generator 1A according to the present embodiment is preferable not only from the viewpoint of reducing the size and weight of the gas generator but also from the viewpoint of reducing the size and weight of the pretensioner module. Is.

  However, when the above configuration is adopted, the distance between the annular groove 15 and the second recess 13 is reduced as compared with the conventional gas generator, which reduces the mechanical strength of the holder 10A in the portion. There is a risk of connection. Here, in the conventional gas generator, the distance between the first recess and the second recess is narrower than the distance between the annular groove and the second recess, and the distance between the first recess and the second recess is short. The mechanical strength of the partition wall portion positioned at the position has determined the pressure resistance performance of the holder, but when the above configuration is adopted, the portion of the holder 10A positioned between the annular groove portion 15 and the second recess portion 13 The mechanical strength determines the pressure resistance performance of the holder 10A.

  Here, if the arrangement position of the annular groove portion is retracted to the position as described above without any improvement in pressure resistance performance, the holder becomes more suitable as the pressure resistance performance decreases during operation of the gas generator. It will be damaged at a low pressure, gas will leak out from the damaged part, and further, the broken part of the holder will be detached from the gas generator due to the gas pressure when the holder is broken. There is a fear.

  Therefore, in the gas generator 1A and the gas generator holder 10A included in the gas generator 1A according to the present embodiment, the configuration described below is employed to solve the above-described problem. FIG. 3 is an enlarged schematic cross-sectional view of region III shown in FIG. 1 of the gas generator in the present embodiment, (A) is a diagram showing a state in which no fracture occurs, and (B) is a fracture. It is a figure which shows the state immediately after having occurred. FIG. 4 is an enlarged schematic cross-sectional view of the main part of the portion corresponding to the region III of the gas generator according to the comparative example, and FIG. 4A is a view showing a state in which no breakage occurs. ) Is a diagram showing a state immediately after the fracture occurs. In the following, the solution will be described with reference to FIG. 3 and FIG. Note that the gas generator according to the comparative example shown in FIG. 4 is configured to generate gas with a configuration in which the position of the annular groove is retracted to the above position without any improvement in pressure resistance performance. It is a vessel.

  As shown in FIG. 3 (A), in the gas generator 1A according to the present embodiment, the corner portion 13d located between the bottom surface 13a and the peripheral surface 13b of the second recess 13 provided in the holder 10A includes: The corner portion located between the bottom surface 15a and the inner peripheral surface 15b of the annular groove portion 15 provided in the holder 10A is configured by a curved surface 13e continuous to both the bottom surface 13a and the peripheral surface 13b adjacent to each other. 15d is configured at a substantially right angle.

  On the other hand, as shown in FIG. 4 (A), in the gas generator 1X according to the comparative example, the corner portion located between the bottom surface 13a and the peripheral surface 13b of the second recess 13 provided in the holder 10X. 13d and the corner | angular part 15d located between the bottom face 15a of the annular groove part 15 provided in the holder 10X, and the internal peripheral surface 15b are comprised at substantially right angle.

  As a result, in the gas generator 1A in the present embodiment, the distance A in the shortest path of the portion connecting the corner portion 13d and the corner portion 15d (that is, the minimum thickness of the holder 10A in the portion) is a comparative example. As compared with that of the gas generator 1X, the mechanical strength in the portion is increased, and the corner portion 13d is bent to reduce the concentration of stress and increase the mechanical strength. become.

  Here, as the shape of the curved surface 13e constituting the corner portion 13d, the curvature radius of the curved surface 13e along the cut surface when the holder 10A is cut along the plane including the axis is 0.5 mm or more. It is preferable that the shape be In addition, also in the conventional gas generator, although the curvature radius along the said cut surface of the said corner | angular part was made into about 0.1 mm-0.3 mm for the reason on a process, this is known, The curved shape of the corner 13d in the embodiment is of a size that can be clearly distinguished from this.

  Therefore, by using the gas generator 1A and the holder 10A included in the gas generator 1A according to the above-described embodiment, sufficient downsizing can be achieved, so that mounting on a vehicle or the like is excellent, and sufficient mechanical strength is achieved. Therefore, it is possible to provide a gas generator having high pressure resistance and a gas generator holder included in the gas generator.

  Further, as shown in FIG. 3B, in the gas generator 1A according to the present embodiment, when the holder 10A is broken, the starting point B1 on the second recess 13 side of the fracture surface B is the second It occurs at a position radially inward of the circumferential surface 13b that defines the recess 13, and the starting point B2 on the annular groove 15 side of the fracture surface B is at a position that matches the inner circumferential surface 15b that defines the annular groove 15. Will occur. This is because the corner portion 13d is configured by the curved surface 13e and the corner portion 15d is configured at a substantially right angle, and the fracture surface B is generated along the shortest path described above. is there.

  On the other hand, as shown in FIG. 4B, in the gas generator 1X according to the comparative example, when the holder 10X breaks, the starting point B1 of the fracture surface B defines the second recess 13. This occurs at a position that coincides with the peripheral surface 13b in the radial direction, and the starting point B2 on the annular groove portion 15 side of the fracture surface B occurs at a position that matches the inner peripheral surface 15b that defines the annular groove portion 15. This is because the corner portion 13d and the corner portion 15d are both formed substantially at right angles, and the fracture surface B is generated along the shortest path described above.

  In the gas generators 1A and 1X after the holders 10A and 10X are broken, the gas pressure is applied to the broken portions of the holders 10A and 10X (the broken portions mainly include the partition wall 14 and the annular protrusion 17). As a result, the broken portion is pushed out in the direction of arrow C in the figure, and is detached from the gas generators 1A and 1X. At that time, shearing occurs at the fracture surface, but the shape of the tip of the fractured portion of the holder 10A, 10X in the traveling direction (that is, the direction of the arrow C) is a tapered shape, and the tip of the fractured portion faces the tip. Since the shape of the non-breaking portion of the portion (the non-breaking portion mainly includes the cylindrical portion 11 and the annular flange portion 16) is a shape narrowed along the arrow C direction, A shear fracture occurs in which the fractured portion separates from the non-ruptured portion while deformation occurs mutually in the fractured portion.

  Here, as described above, in the gas generator 1A according to the present embodiment, since the starting point B1 of the fracture surface B is located inside the peripheral surface 13b of the second recess 13, the fracture surface B The length E along the radial direction of the gas generator is longer than that of the gas generator 1X according to the comparative example, and the resistance when the fractured portion is detached from the non-ruptured portion is increased. In other words, in the gas generator 1A according to the present embodiment, the portion shown as the region D1 in FIG. 3B is included in the non-breaking portion, and therefore the gas generator 1X according to the comparative example , The resistance at the time when the fractured portion is separated from the non-breakable portion is increased by the presence of the region D1.

  Therefore, the gas generator 1A and the holder 10A included in the gas generator 1A according to the present embodiment described above are excellent in mountability to a vehicle or the like by being sufficiently reduced in size, and have a high pressure resistance against shear fracture. It can be set as the gas generator provided with performance, and the holder for gas generators provided in this.

  The length E along the radial direction of the fracture surface B described above is preferably as long as possible in order to improve the pressure resistance performance. Therefore, the peripheral surface 13b of the second recess 13 is annular at least in the radial direction. It is preferable that the groove portion 15 is located inside the inner peripheral surface 15b.

  FIG. 5 is an enlarged schematic cross-sectional view of a main part of a portion corresponding to the region III of the gas generator according to the modification based on the present embodiment, and (A) is a diagram showing a state in which no breakage occurs. (B) is a figure which shows the state immediately after a fracture | rupture arises. Next, with reference to this FIG. 5, the gas generator which concerns on a modification, and the holder for gas generators provided in this are demonstrated.

  As shown in FIG. 5A, the gas generator 1B and the gas generator holder 10B according to the modification include the gas generator 1A and the gas generator holder 10A in the present embodiment described above, and the annular groove portion 15 of the holder. Only the shape of the corner 15d is different. That is, in the gas generator 1B and the gas generator holder 10B according to the modification, the corner portions 13d located between the bottom surface 13a and the peripheral surface 13b of the second recess 13 provided in the holder 10B are adjacent to each other. In addition to the curved surface 13e continuous to both the bottom surface 13a and the peripheral surface 13b, the corner portion positioned between the bottom surface 15a and the inner peripheral surface 15b of the annular groove 15 provided in the holder 10B. 15d is constituted by a curved surface 15e continuous to both of the adjacent bottom surface 15a and inner peripheral surface 15b.

  Therefore, in the gas generator 1B according to this modification, the distance A in the shortest path of the portion connecting the corner portion 13d and the corner portion 15d (that is, the minimum thickness of the holder 10B in the portion) is the above-described embodiment. As compared with that of the gas generator 10A in this form, the mechanical strength in the portion is further increased, and not only the corner portion 13d but also the corner portion 15d are bent, thereby concentrating stress. Is further relaxed and the mechanical strength is further increased.

  Here, as the shape of the curved surface 15e constituting the corner portion 15d, the curvature radius of the curved surface 15e along the cut surface when the holder 10B is cut along the plane including the axis is 0.5 mm or more. It is preferable that the shape be In addition, also in the conventional gas generator, although the curvature radius along the said cut surface of the said corner | angular part was made into about 0.1 mm-0.3 mm for the reason on a process, this is known, The curved shape of the corner 15d in the modification is of a size that can be clearly distinguished from this.

  Therefore, by using the gas generator 1B according to the above-described modification and the holder 10B included in the gas generator 1B, sufficient downsizing can be achieved, so that mounting on a vehicle or the like is excellent, and sufficient mechanical strength is achieved. Therefore, it is possible to provide a gas generator having high pressure resistance and a gas generator holder included in the gas generator.

  As shown in FIG. 5B, in the gas generator 1B according to this modification, when the holder 10A is broken, the starting point B1 on the second recess 13 side of the fracture surface B is the second This occurs at a position radially inward of the circumferential surface 13b that defines the recess 13, and the starting point B2 on the annular groove 15 side of the fracture surface B is in the radial direction of the inner circumferential surface 15b that defines the annular groove 15. It will occur at the outer position. This is because the corner portion 13d is configured by the curved surface 13e and the corner portion 15d is configured by the curved surface 15e, and the fracture surface B is generated along the shortest path described above. It is.

  Therefore, in the gas generator 1B according to the present modification, the length E along the radial direction of the fracture surface B is longer than that of the gas generator 1A in the present embodiment described above. Thus, the resistance when the fractured portion is separated from the non-ruptured portion is further increased. In other words, in the gas generator 1B according to this modification, not only the portion shown as the region D1 in FIG. 5B but also the portion shown as the region D2 is included in the non-breaking portion. When compared with the gas generator 1A in the present embodiment described above, the resistance when the fractured portion is separated from the non-ruptured portion is increased by the presence of the region D2.

  Therefore, by using the gas generator 1B according to the above-described modification and the holder 10B included in the gas generator 1B, sufficient downsizing can be achieved, so that it can be easily mounted on a vehicle or the like, and has a high pressure resistance against shear fracture. It can be set as the gas generator provided with performance, and the holder for gas generators provided in this.

  In the following, the gas generator according to the comparative example described above is actually manufactured, and the gas generator according to the above-described embodiment of the present invention and the gas generator according to the modification are referred to as Example 1 and Example 2, respectively. A verification test for verifying the effect of the present invention by actually making and operating these components to intentionally shear fracture the holder and actually measuring the fracture pressure will be described. FIG. 6 is a table showing the results of a verification test for verifying the pressure resistance performance of the gas generators according to the comparative example and Examples 1 and 2. 7 to 9 are photographs after shear fracture of the gas generator holders according to the comparative example and Examples 1 and 2, respectively.

  In the comparative example, the holder 10X having the shape shown in FIG. 4 was manufactured using an aluminum alloy as a material, and five samples of the gas generator 1X were manufactured using the holder 10X. Here, the shapes of the corner portion 13d and the corner portion 15d shown in FIG. 4 are basically substantially right angles as shown in the figure. However, the corner portion 13d and the corner portion 15d are strict for processing reasons. In meaning, it includes a curved surface with a radius of curvature of R = 0.15 mm.

  In Example 1, the holder 10A having the shape shown in FIGS. 2 and 3 was manufactured using an aluminum alloy as a material, and five samples of the gas generator 1A having the structure shown in FIGS. 1 and 3 were manufactured using the holder 10A. Here, the curvature radius of the curved surface 13e constituting the corner portion 13d shown in FIGS. 1 and 3 was R = 0.65 mm. The shape of the corner 15d shown in FIGS. 1 and 3 is basically a right angle as shown in the figure, but the corner 15d has a radius of curvature of R in a strict sense for processing reasons. = 0.15 mm curved surface is included.

  In Example 2, the holder 10B having the shape shown in FIG. 5 was manufactured using an aluminum alloy as a material, and five samples of the gas generator 1B were manufactured using the holder 10B. Here, the curvature radius of the curved surface 13e and the curved surface 15e constituting the corner portion 13d and the corner portion 15d shown in FIG. 5 is R = 0.65 mm.

  The difference in structure of the gas generators according to the comparative example and Examples 1 and 2 is only the shape of the two corners 13d and 15d described above, and the other parts are all in common. did.

  The cups of the gas generators according to these comparative examples and Examples 1 and 2 were filled with 1500 mg of a gas generating agent mainly composed of smokeless explosive, and these gas generators were placed in an airtight tank having an internal capacity of 3.5 cc. I set it. In addition, the pressure sensor which can measure an internal pressure (pressure in an airtight tank) was installed in the airtight tank. Then, the gas generator according to the comparative example and Examples 1 and 2 is operated by operating the igniter, and the maximum value of the internal pressure of the airtight tank at that time is measured by the pressure sensor, so that the holder is shear broken. The breaking pressure to be confirmed.

  As shown in FIG. 6, in the comparative example, the average value of the breaking pressure at which the holder sheared and fractured was 177.9 MPa, whereas in Example 1, the average value of the breaking pressure at which the holder sheared and fractured was In Example 2, the average value of the fracture pressure at which the holder sheared and fractured was further improved to 199.1 MPa. Based on the results, when the pressure resistance performance in the comparative example is used as a reference, the pressure resistance performance is improved by about 6% in Example 1, and is improved by about 12% in Example 2.

  From these results, according to the present invention, it was confirmed that the pressure resistance performance can be reliably improved as compared with the conventional one.

  As shown in FIGS. 7 to 9, as a result of observing the holders 10 </ b> A to 10 </ b> C after the shear fracture, the corner 13 d of the second recess 13 and the annular groove in both the comparative example and Examples 1 and 2 It is confirmed that there is a fracture between the 15 corners 15d and a trace F of deformation due to shearing occurs in the vicinity of the portion where the fracture surface and the peripheral surface 13b of the second recess 13 are continuous. It was confirmed that Here, the range in which the trace F of deformation due to shearing occurs is longer in the axial direction in Example 1 than in the comparative example, and in Example 2 compared with Example 1, respectively. Among the comparative examples and Examples 1 and 2, it was confirmed that the trace F was generated in the farthest position from the position where the bottom surface 13a of the second recess 13 was present in Example 2. This means that a greater force was required in Example 1 compared to the comparative example and in Example 2 compared to Example 1 in order for the rupture portion to disengage from the non-ruptured portion (ie, greater resistance). Has occurred).

  The above-described embodiment and its modifications and examples disclosed herein are illustrative and non-restrictive in every respect. The technical scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  1A, 1B, 1X gas generator, 10A, 10B, 10X holder, 11 cylindrical portion, 11a outer peripheral surface, 12 first concave portion, 12a bottom surface, 12b peripheral surface, 13 second concave portion, 13a bottom surface, 13b peripheral surface, 13d Corner part, 13e curved surface, 13f engagement groove, 14 partition wall part, 14a through hole, 15 annular groove part, 15a bottom surface, 15b inner peripheral surface, 15c outer peripheral surface, 15d corner part, 15e curved surface, 16 annular flange part, 17 Annular projection, 18 fixed part, 20 igniter, 21 ignition part, 22 terminal pin, 23 base part, 25 cover member, 25a bottom wall part, 26 guide hole, 28 seal member, 30 cup, 31 side wall part, 32 Bottom wall part, 33 flange part, 34 accommodation space, 35 gas generating agent.

Claims (9)

A bottomed substantially cylindrical cup loaded with a gas generating agent that generates gas by burning;
An igniter including an igniter containing an igniting agent that burns the gas generating agent by igniting at the time of operation, and a terminal pin connected to the igniting unit to ignite the igniting agent;
A substantially cylindrical holder that is assembled to the cup coaxially so as to close the open end of the cup and holds the igniter so that the ignition portion faces the gas generating agent. ,
The holder is provided on an axial end surface on the side facing the cup, and is provided on a first recess for receiving and holding the igniter, and on an axial end surface on the side not facing the cup, and the terminal pin is disposed. And defining a second recess for receiving and holding a connector for external connection of the igniter via the terminal pin, a bottom surface of the first recess, and a bottom surface of the second recess. A partition wall that partitions the first recess and the second recess, and an annular groove that is provided on the outer peripheral surface and receives and holds the opening edge of the cup inserted along the axial direction;
The bottom surface of the annular groove is provided in a portion that radially surrounds the partition of the holder,
The gas generator in which the corner | angular part located between the bottom face of the said 2nd recessed part and the surrounding surface of the said 2nd recessed part is comprised by the curved surface which continues in any of these adjacent surfaces.   The gas generator according to claim 1, wherein a radius of curvature of the curved surface along the cut surface when the holder is cut along a plane including an axis is 0.5 mm or more.   The gas generator according to claim 1 or 2, wherein a peripheral surface of the second recess is located on an inner side than an inner peripheral surface of the annular groove portion in a radial direction.   The corner part located between the bottom face of the said annular groove part and the internal peripheral surface of the said annular groove part is comprised by the curved surface which continues in any of these adjacent surfaces. A gas generator according to 1. The opening edge of the cup is provided with a flange portion extending outward,
The opening edge of the cup is received and held by the annular groove portion by caulking the annular flange portion, which is a portion defining the outer peripheral surface of the annular groove portion, toward the inside so as to cover the flange portion. Item 5. The gas generator according to any one of Items 1 to 4. A holder for a substantially cylindrical gas generator that is used by assembling a bottomed substantially cylindrical cup that holds an igniter for burning a gas generating agent and loaded with the gas generating agent,
A first recess provided on an axial end face on the side where the cup is assembled, for receiving and holding the igniter;
A second recess provided on the axial end surface on the side where the cup is not assembled, the terminal pin of the igniter being disposed, and a second recess for receiving and holding a connector for external connection of the igniter via the terminal pin;
A partition wall partitioning the first recess and the second recess by defining a bottom surface of the first recess and a bottom surface of the second recess;
An annular groove for receiving and holding the opening edge of the cup that is provided on the outer peripheral surface and is inserted along the axial direction;
The bottom surface of the annular groove is provided in a portion surrounding the partition wall in the radial direction,
A gas generator holder, wherein a corner located between the bottom surface of the second recess and the peripheral surface of the second recess is formed by a curved surface continuous with any of these adjacent surfaces.   The gas generator holder according to claim 6, wherein a radius of curvature of the curved surface along the cut surface when cut along a plane including the axis is 0.5 mm or more.   The holder for gas generators according to claim 6 or 7 with which the peripheral surface of said 2nd crevice is located in the inner side rather than the internal peripheral surface of said annular groove part in a diameter direction.   The corner part located between the bottom face of the said annular groove part and the internal peripheral surface of the said annular groove part is comprised by the curved surface which continues in any of these adjacent surfaces. A holder for a gas generator according to 1.