Ignition assembly and gas generator

Abstract

Igniter arrangement (100), comprising: an igniter (1) configured to cause the combustion of an ignition charge with an ignition current supplied via an electrically conductive pin (5) and to eject a combustion product, a metal collar (2) arranged around the detonator (1), and a resin connecting part (3) configured to connect the detonator (1) and the metal sleeve (2), which are non-contacting each other, through a resin material, and to create a connected state in which the detonator (1) and the metal sleeve (2) are connected such that part of the electrically conductive pin (5), to which a voltage can be applied, is exposed. wherein the metal cuff (2) has: a connecting surface part (8) with an annular surface that surrounds a circumference of a part of the detonator (1) in the connected state, wherein the annular surface is covered by the synthetic resin connecting part (3) and is brought into contact with the synthetic resin connecting part (3), a first connecting groove (11, 21, 31) which opens in the annular surface of the connecting surface part (8) in a vertical direction of the detonator (1) and extends circularly around the detonator center, wherein the first connecting groove (11, 21, 31) contains a first inner circumferential edge (11a, 21a, 31a) in an opening, and the first inner circumferential edge (11a, 21a, 31a) has a first corner part (11c, 21c, 31c) which is formed on the entire circumference of the first inner circumferential edge (11a, 21a, 31a) between the annular surface and an inner wall surface of the first connecting groove (11, 21, 31) and has a first predetermined angle (θ1), and characterized by the fact that a second connecting groove (12, 22, 32) is formed in the first connecting groove (11, 21, 31), which opens in the inner wall surface of the first connecting groove (11, 21, 31) under the first corner part (11c, 21c, 31c) also in the vertical direction of the detonator (1) and extends in an annular shape in the circumferential direction of the detonator (1), wherein the second connecting groove (12, 22, 32) has a second inner circumferential edge (12a, 22a, 32a) in an opening of the second connecting groove (12, 22, 32), and the second inner circumferential edge (12a, 22a, 32a) has a second corner part (12c, 22c, 32c) which extends along the entire circumference of the second inner circumferential edge (12a, 22a, 32a) between the inner wall surface of the first connecting groove (11, 21, 31) and an inner wall surface of the second connecting groove (12, 22, 32) and has a second predetermined angle (θ3), wherein the connected state is established in which the resin connecting part (3) has entered the first connecting groove (11, 21, 31) and the second connecting groove (12, 22, 32), and the resin connecting part (3) presses the first corner part (11c, 21c, 31c) and the second corner part (12c, 22c, 32c).

Description

[Field of invention]

[0001] The invention relates to an igniter assembly and a gas generator. The igniter assembly is obtained by bonding, using a synthetic resin material, an igniter, which is actuated by the supply of an ignition current, to a metal sleeve. The gas generator contains the igniter assembly and generates a combustion gas by causing a gas generating agent to be burned upon actuation of the igniter. [Background]

[0002] An igniter assembly containing an igniter to which an ignition current is supplied for actuation is formed by fixing the igniter to a metal collar using a synthetic resin material. The igniter assembly is widely used and is attached, for example, to a safety device such as an airbag inflator using the metal collar. For such a safety device, it is important to ensure that the igniter assembly is actuated when needed and that the device in which the igniter is integrated functions reliably. Therefore, moisture absorption of the ignition charge must be avoided.In the igniter assembly, when the sealing performance of a resin material between the igniter and the metal sleeve is low, moisture from the ambient air outside the igniter assembly enters the device through a fine gap (for example, a gap between the metal sleeve and the resin) in the igniter assembly, which may cause a defect. In view of this, Patent Document 1 discloses a technique for improving the sealing performance by utilizing a shrinkage force of a resin material by forming and arranging a plurality of annular grooves, which are held in contact with the resin material, in a predetermined area of ​​a metal sleeve surrounding an igniter, and then injecting the resin material into the grooves.

[0003] As another technique for improving the sealing performance using a resin material between the igniter and the metal collar in the igniter assembly, for example, Patent Document 2 discloses a technique of forming annular protrusions in a predetermined part of a metal collar surrounding an igniter and then bonding the igniter and the metal collar such that the resin material clamps the protrusions. [Reference list][Patent documents] [Patent Document 1] JP 2006-256561 A [Patent Document 2] JP 4021178 B [Patent Document 3] JP 2003-226222 A

[0004] From US 6 508 175 B1 a generic igniter arrangement with the features of the introductory part of claim 1 is known.

[0005] Further prior art is known from the documents DE 195 33 606 A1, JP 3 134 430 U, DE 60 2006 000 920 T2, DE 200 20 103 U1, AT 010 051 U1, DE 10 2017 109 209 A1 and DE 196 22 025 A1. [Summary][Technical Problem]

[0006] If the number of annular grooves held in contact with a resin material in a metal boot is small, the sealing performance of the resin material between an igniter and the metal boot in the igniter assembly is reduced, and accordingly, the likelihood of rust formation on the metal boot associated with water ingress is increased. When rust forms, the sealing performance is greatly reduced, and more water enters. Thus, moisture enters the device in which the igniter assembly is integrated, hindering normal operation.

[0007] Furthermore, if a plurality of annular grooves, which are held in contact with the resin material, are arranged in the metal sleeve as in the prior art, the contact area between the resin material and the metal sleeve can be increased. Accordingly, an improvement in the sealing performance of the resin material between the igniter and the metal sleeve is expected. However, more space is required for arranging the plurality of grooves around the igniter in the metal sleeve. This increases the width of the metal sleeve around the igniter and prevents size reduction.

[0008] In view of the above-described problems, it is an object of the invention to provide a technique for achieving a size reduction of a metal sleeve, with which a relatively high degree of sealing performance can be maintained between the metal sleeve and a synthetic resin material for fixing an igniter in an igniter assembly. [Problem solving]

[0009] As a solution to the above-mentioned problem, the present invention employs a configuration in which annular connecting grooves are formed in an overlapping manner on a connecting surface portion of a metal collar around an igniter. With this configuration, a relatively large contact area between the resin material and the metal collar can be ensured, and the formation and arrangement of a plurality of connecting grooves in a radial direction with the igniter as a center can be omitted. This enables a size reduction of the metal collar.

[0010] In particular, according to one embodiment, the invention comprises an igniter arrangement having the features of claim 1.

[0011] In the igniter assembly according to the invention, the resin bonding part is arranged between the igniter and the metal sleeve to establish the bonded state in which the igniter and the metal sleeve are integrated. In the bonded state, contact between the igniter and the metal sleeve is avoided. Therefore, for the bonded state established by the resin bonding part, it is only necessary to bond the igniter to the metal sleeve via the resin material therebetween, so that insulation is ensured between the electrically conductive pin and the metal sleeve. As long as a combustion product of the ignition charge can be ejected, the bonding method for connecting the igniter to the metal sleeve using the resin bonding part is not limited to a specific method.Furthermore, in the igniter assembly, an ejection surface from which a combustion product of the igniting charge in the igniter is ejected and a relative positional relationship of the electrically conductive pin through which an igniting current is supplied to the igniter may be used in accordance with the purpose of use and the like of the igniter assembly.

[0012] The metal sleeve includes the connecting surface portion covered by the resin connecting portion and brought into contact with the resin connecting portion in the connected state. Furthermore, the annular first connecting groove and the annular second connecting groove are arranged in the connecting surface portion on the inner side of the first connecting groove.The relative positional relationship of the first connecting groove and the second connecting groove is not a relationship in which these grooves are arranged in the radial direction with the igniter as a center in the connected state, but a relative positional relationship in which, when the second connecting groove opens in the inner wall surface of the first connecting groove, the first connecting groove and the second connecting groove are arranged in an overlapping manner, or preferably a relative positional relationship in which these grooves are arranged in the depth direction of the first connecting groove. With this configuration, an increase in the width of the connecting surface part in the radial direction for arranging the two annular connecting grooves can be prevented, and the size of the metal collar in that direction can be reduced.

[0013] Furthermore, the first inner peripheral edge in the opening part of the first connecting groove crosses the above-described first imaginary line on the entire circumference and has the first corner part. With this configuration, the resin connecting part entering the first connecting groove during injection molding causes a shrinkage force to act on the first corner part of the entire circumference of the first inner peripheral edge during curing, and continuously presses the first corner part. This exerts sealing performance around the first inner peripheral edge. Furthermore, the injected resin material also flows into the second connecting groove and cures. The second inner peripheral edge in the opening part of the second connecting groove also crosses the above-described second imaginary line on the entire circumference and has the second corner part.In the connected state, the resin joint part also entering the second joint groove causes a shrinkage force to act on the second corner part on the entire circumference of the second inner peripheral edge, and continuously presses the second corner part. This provides sealing performance around the second inner peripheral edge. Note that the second joint groove is a groove that opens below the first corner part, that is, in the depth direction of the first joint groove, and is independent of the second inner peripheral edge and the first inner peripheral edge. Thus, a pressing force acting on the second corner part can be prevented from adversely affecting the sealing performance at the first corner part.

[0014] As described above, in the igniter assembly according to the invention, an increase in the size of the metal sleeve can be prevented and the sealing performance between the resin connecting part and the metal sleeve can be improved by the overlapping arrangement of two annular connecting grooves. This greatly contributes to a size reduction of the metal sleeve, while simultaneously maintaining a relatively high degree of sealing performance by the resin material between the igniter and the metal sleeve in the igniter assembly.

[0015] In the igniter assembly described above, a bottom part of the second connecting groove may be deeper than a bottom part of the first connecting groove, and the inner peripheral edge of the opening part of the second connecting groove may be located outside the inner peripheral edge of the opening part of the first connecting groove, with the igniter in the connected state as a center. With this configuration, a shrinkage force of the resin material of the resin connecting part acts on the inner peripheral edge of the opening part of the second connecting groove and the opening part of the inner peripheral edge of the first connecting groove in an overlapping manner, and a state for effectively pressing the first corner part and the second corner part can be provided. Thereby, the sealing performance by the resin material between the igniter and the metal collar is maintained at a relatively high level.

[0016] In the igniter assembly described above, the opening direction of the opening portion of the second connecting groove may coincide with the opening direction of the opening portion of the first connecting groove. When the opening directions of the two connecting grooves coincide with each other, the connecting grooves can be formed relatively easily in the metal sleeve. For example, cutting or the like can be performed to form the connecting grooves while maintaining a relative posture of a processing tool with respect to the metal sleeve. This can simplify the operation for forming the two connecting grooves.

[0017] Furthermore, in the igniter assembly described above, the first predetermined angle and the second predetermined angle may both be 90 degrees. The first predetermined angle and the second predetermined angle are angles formed at the first corner portion and the second corner portion, respectively, such that the shrunken resin material can cause a pressing force to effectively act on the inner peripheral edge of the first connecting groove and the inner peripheral edge of the second connecting groove during shrinkage of the resin material of the resin connecting portion. By setting the predetermined angles to 90 degrees, the operation for forming the two connecting grooves can be simplified.As long as the shrunken resin material can cause a pressing force to be supplied to the inner peripheral edge of the first connecting groove and the inner peripheral edge of the second connecting groove, the first predetermined angle and the second predetermined angle may be any angles, and the two predetermined angles may be different from each other.

[0018] The invention can be understood as a gas generator that causes a gas generating agent to be combusted by an igniter and discharges a combustion gas. According to one embodiment of the invention, a gas generator may include the above-described igniter assembly, a housing configured to accommodate the igniter assembly, the housing being filled with a gas generating agent whose combustion is caused by actuation of the igniter included in the igniter assembly, and an exhaust port configured to expel the combustion gas generated by the combustion of the gas generating agent to the outside, the exhaust port being provided in the housing.In the gas generator described above, moisture absorption of the ignition charge in the igniter assembly can be effectively suppressed, and by using the igniter assembly described above, the operation of the gas generator can be ensured and a size reduction of the gas generator can be implemented more easily. [Advantageous effects of the invention]

[0019] According to one embodiment of the invention, a size reduction of the metal sleeve is achieved and at the same time a relatively high degree of sealing performance can be maintained by the synthetic resin material between the igniter and the metal sleeve in the igniter assembly. [Brief description of the drawings] [ Fig. 1] Fig. 1 is a schematic view showing a configuration of a gas generator having an igniter assembly according to the present invention incorporated therein. [ Fig. 2] Fig. 2 is a cross-sectional view of the igniter assembly according to the present invention. [ Fig. 3A] Fig. 3A is a first cross-sectional view of a device used in the igniter assembly of Fig. 2 included metal cuff. [ Fig. 3B] Fig. 3B is a first cross-sectional view of a device used in the igniter assembly of Fig. 2 included metal cuff. [ Fig. 3C] Fig. 3C is a first cross-sectional view of a device used in the igniter assembly of Fig. 2 included metal cuff. [ Fig. 4A] Fig. 4A is a second cross-sectional view of the igniter assembly of Fig. 2 included metal cuff. [ Fig. 4B] Fig. 4B is a second cross-sectional view of the igniter assembly of Fig. 2 included metal cuff. [ Fig. 4C] Fig. 4C is a second cross-sectional view of the igniter assembly of Fig. 2 included metal cuff. [ Fig. 5A] Fig. 5A is a third cross-sectional view of the igniter assembly of Fig. 2 included metal cuff. [ Fig. 5B] Fig. 5B is a third cross-sectional view of the igniter assembly of Fig. 2 included metal cuff. [ Fig. 5C] Fig. 5C is a third cross-sectional view of the igniter assembly of Fig. 2 included metal cuff. [Description of embodiments]

[0020] An igniter assembly and a gas generator incorporating the igniter assembly according to an embodiment of the invention will be described below with reference to the drawings. Note that the embodiment described below is exemplary, and the invention is not limited to the configurations of the embodiment. First embodiment

[0021] Fig. 1 shows an embodiment in which a gas generator is formed using an igniter assembly 100. The gas generator is not limited to an airbag gas generator and can also be used as an airbag gas generator, a seatbelt pretensioner, a curtain airbag, or various types of actuators, or the like. In the gas generator, a casing 103 is formed by combining a diffuser shell 101 in which a gas discharge port 104 is formed with a closure shell 102 that closes the diffuser shell 101, and the igniter assembly 100 is disposed in the casing 103. Note that before the igniter assembly 100 is actuated, the gas discharge port 104 is closed from within the casing 103 by a sealing tape 115 made of aluminum.The igniter assembly 100 described in detail below generates a combustion gas for, for example, inflating an airbag with an igniter 1 contained in the igniter assembly 100 (see . Fig. 2) which is actuated to cause ignition and combustion of a gas generating agent filled in the housing 103.

[0022] In particular, the gas generator of Fig. 11, an inner cylindrical member 108 having a peripheral wall with a plurality of flame transmission holes 107 is arranged at the center of the casing 103. A space 109 for accommodating the igniter assembly 100 and a booster charge 111 is formed in the inner cylindrical member 108, and a combustion chamber 110 for accommodating the gas generating agent 105 is formed outside the inner cylindrical member 108 in a radial direction. In the combustion chamber 110, the gas generating agent 105 is held by a bottom plate 116 formed in a substantially annular shape. As the booster charge 111, a gas generating agent having favorable ignitability and a combustion temperature higher than that of the gas generating agent 105 can be used. Preferably, the combustion temperature of the transfer charge 111 is in the range of 1,700 °C to 3,000 °C.The transfer charge 111 is, for example, a known material containing nitroguanidine (34 wt.%) and strontium nitrate (56 wt.%). Alternatively, a known black powder (boron nitrate) can be used as the transfer charge. Furthermore, a gas generating agent with a relatively low combustion temperature can be used as the gas generating agent 105, wherein the combustion temperature of the gas generating agent 105 is preferably in the range of 1,000°C to 1,700°C. The gas generating agent 105 is, for example, a known material containing guanidinium nitrate (41 wt.%), base copper nitrate (49 wt.%), a binder, and an additive.

[0023] Furthermore, the igniter assembly 100 is fixed in a lower part of the inner cylindrical member 108. The igniter assembly 100 can be fixed to the inner cylindrical member 108 by, for example, crimping the inner cylindrical member 108 at an opening end 112 side thereof for fixing a metal collar 2 of the igniter assembly 100 (see Fig. 2). Furthermore, in the inner cylindrical member 108, the opening end 112 on a side where the igniter assembly 100 is received is connected to the closure shell 102 by welding or the like.

[0024] The gas generating agent 105 is housed in the combustion chamber 110, and a filter 106 is disposed on the outside thereof. The filter 106 collects a combustion residue contained in the combustion gas generated by burning the gas generating agent 105 and cools the combustion gas. The filter 106 is formed in a tubular shape from a laminated metal mesh or the like and has an outer peripheral surface facing an inner peripheral surface of the housing 103. Preferably, a space 113 serving as a gas flow passage is formed between the outer peripheral surface of the filter 106 and the inner peripheral surface of the housing 103 so that the entire area of ​​the filter 106 is utilized.The outer peripheral surface of the filter 106 is held by a porous cylindrical perforated plate 114, and outward expansion in the radial direction is prevented by contact with the inner peripheral surface of the housing 103.

[0025] In the gas generator with this configuration, when the igniter assembly 100 is actuated, the transfer charge 111 disposed adjacent thereto is ignited and combusted. The resulting flame is guided into the combustion chamber 110 through the flame transfer holes 107 in the inner cylindrical member 108. This flame ignites and combusts the gas generating agent 105 in the combustion chamber 110, thereby generating combustion gas. The combustion gas is filtered and cooled as it passes through the filter 106, breaks through the sealing band 115 closing the gas discharge port 104, and is discharged to the outside through the gas discharge port 104.

[0026] In the following, the igniter assembly 100 is described with reference to Fig. 2 described. Fig. 2 is a cross-sectional view of the igniter assembly 100 in a connected state in which the igniter 1 is connected to the metal collar 2 (metal collar) by a resin connecting part 3 formed of a synthetic resin material. Thus, in the igniter assembly 100, a metal collar 2 and an electric igniter 1 are integrated by the resin connecting part 3.

[0027] The igniter 1 comprises a pair of electrically conductive pins 5, wherein combustion of the ignition charge is carried out with an ignition current supplied via the electrically conductive pins 5. In a cup 4 of the igniter 1, a bridge wire (not shown) extends between the electrically conductive pins 5 while maintaining an electrically insulating state between them. The ignition charge is accommodated in the cup 4, wherein the ignition charge is brought into contact with the bridge wire extending between the electrically conductive pins 5. The ignition charge is ignited and burns by heat generation of the bridge wire, thereby producing a combustion product. Furthermore, due to the pressure increase in the cup 4 during combustion of the ignition charge, an upper surface of the cup 4 is perforated, and the combustion product is expelled from the perforated part. In the gas generator of Fig. 1, the transfer charge 111 arranged in the space 109 is exposed to the ejected combustion product.

[0028] The metal boot 2 is formed in a substantially tubular shape and includes a connector receiving portion 6 that receives a connector (not shown) that connects to the electrically conductive pins 5 of the igniter 1, and a resin filling portion 7 that contacts the resin connecting portion 3. A connecting surface portion 8 that extends annularly toward the center of the metal boot 2 (to a position where the igniter 1 is disposed with respect to the metal boot 2) is provided on the resin filling portion 7 side of the connector receiving portion 6, and distal ends of the connecting surface portion 8 form internal holes through which the electrically conductive pins of the igniter 1 extend toward the connector receiving portion 6 side.Furthermore, the metal sleeve 2 is provided at one end on the resin filling part 7 side and adjacent to the connecting surface part 8 with an annular upright projection wall 10. In the embodiment shown in . Fig. In the connected state shown in Figure 2, the electrically conductive pins 5 of the igniter 1 are arranged in a space surrounded by the projection wall 10.

[0029] Furthermore, in the igniter assembly 100, the igniter 1 is integrated with the metal sleeve 2 through the resin bonding part 3. The integration of the igniter 1 and the metal sleeve 2 through the resin bonding part 3 will be described below. The bonding surface part 8 and the protrusion wall 10 of the metal sleeve 2 are covered with and brought into contact with a resin material of the resin bonding part 3 that integrates the igniter 1 and the metal sleeve 2. Due to the contact of the resin material, a bond between the metal sleeve 2 and the resin material is ensured, and the formation of a gap through which moisture might pass is prevented. This can improve sealing performance. Sealing performance based on the contact of the resin material is provided by utilizing mold shrinkage and shrinkage after molding the resin material.Therefore, the resin material integrating the igniter 1 and the metal collar 2 is preferably injection molded. During injection molding, the resin material is preferably injected to cover the joint surface portion 8 and the protrusion wall 10 of the metal collar 2. During injection molding, the resin material preferably undergoes casting shrinkage or post-casting shrinkage, providing a pressing force acting on the joint surface portion 8 and the protrusion wall 10. This can enhance the sealing performance.

[0030] In this embodiment, the resin material of the resin joint part 3 preferably has a molding shrinkage ratio of 1% or less, and more preferably, a molding shrinkage ratio in the range between 0.1% and 0.8%. If the resin material exhibits excessive molding shrinkage, warpage, warping, or sink marks may occur in a liquefied resin. This may create an undesirable gap between the igniter 1 and the resin joint part 3 or between the metal collar 2 and the resin joint part 3. Therefore, a resin material with an appropriate molding shrinkage ratio should be used.

[0031] It should be noted that a resin material containing an inorganic filler such as glass fiber has a molding shrinkage ratio that differs in a flow direction (MD) and a direction (TD) orthogonal to the flow direction of the injection-molded resin due to the orientation of the inorganic filler. Such a resin material has a molding shrinkage ratio (in the flow direction and the orthogonal direction) that does not cause an undesirable gap at least between the igniter 1 and the resin connecting part 3, between the metal collar 2 and the resin connecting part 3, etc. Furthermore, the resin material containing the inorganic filler has a molding shrinkage ratio that is larger in the direction orthogonal to the resin flow direction than in the resin flow direction.Therefore, the joining surface part 8 and the protrusion wall 10 preferably have surfaces that receive a pressing force generated by the shrinkage of the resin material in the direction orthogonal to the flow direction of the resin material. With such a configuration, pressing against the joining surface part 8 and the protrusion wall 10 can be implemented by the resin material undergoing molding shrinkage, and a shrinkage ratio in the flow direction of the resin material can be suppressed. Thus, in order to establish the joined state in which the joining surface part 8 and the protrusion wall 10 are arranged to form the igniter 1 as shown in FIG. Fig. 2, the resin material forming the resin connecting part 3 is preferably arranged in a flow direction along an axial direction (vertical direction in Fig. 2) of the tubular metal sleeve 2.

[0032] Furthermore, a thermosetting resin can be used as the resin material of the resin connecting part 3, but the resin material for injection molding is preferably a thermoplastic resin, and more preferably a resin containing glass fibers or other inorganic fillers. The resin has a water absorption ratio after immersion in water for 24 hours at 23°C (these conditions apply to the following specifications) of preferably 0.005% to 0.5%, and more preferably 0.005% to 0.3%, and a tensile strength of preferably 70 MPa to 250 MPa, and more preferably 100 MPa to 250 MPa. Furthermore, a resin with a linear expansion coefficient of 8×10 -5 / °C or less, a tensile strength of 100 MPa or more, and a dielectric breakdown voltage of 10 MV / m or more can be used. In particular, the tensile strength is preferably from 170 MPa to 250 MPa. Examples of the resin material are nylon 612, polyarylate, polybutylene terephthalate, polyphenylene sulfide, or a liquid crystal polymer. These exemplary resin materials may contain an inorganic filler such as glass fibers, a glass filler, and minerals. Specifically, 20 mass % to 80 mass % of glass fibers may be contained in polybutylene terephthalate, 20 mass % to 80 mass % of glass fibers may be contained in polyphenylene sulfide, or 20 mass % to 80 mass % of minerals may be contained in a liquid crystal polymer.Particularly, when a glass fiber-reinforced resin containing glass fibers is used for molding, the orientation of the glass fibers is preferably adjusted to extend along the extension direction in which the electrically conductive pins 5 are inserted into the resin material. At this time, the molding shrinkage ratio is increased in a thickness direction of the electrically conductive pins 5 to reliably prevent moisture from penetrating between the electrically conductive pins 5 and the resin material. Furthermore, the proportion of the inorganic filler in each of the resin materials is preferably in the range of 20 mass % to 50 mass %.

[0033] In the following, with reference to Fig. 3 describes the development of the sealing performance between the resin material and the metal sleeve 2 at the joining surface part 8. As described above, the joining surface part 8 is annularly formed to surround a part of the igniter 1 adjacent to the center of the interior of the substantially tubular metal sleeve 2 in which the igniter 1 is disposed in the joined state. Furthermore, a first connecting groove 11 and a second connecting groove 12 are formed in a surface of the joining surface part 8 (hereinafter referred to as the "upper surface of the joining surface part 8") on the resin filling part 7 side. Fig. 3A shows a state in a cross-sectional view of the metal sleeve 2 along a cross section including an axial line. Fig. 3B shows a state in which the connecting surface part 8 in which the first connecting groove 11 and the second connecting groove 12 are provided is partially enlarged. Fig. Figure 3C shows the geometric structure of a first corner part 11c and a second corner part 12c, which are provided at the corresponding connecting grooves. The right side in Fig. 3B and Fig. 3C corresponds to the center side of the metal sleeve 2 and the left side corresponds to the peripheral edge side of the metal sleeve 2.

[0034] The first connecting groove 11 is a groove that opens in the upper surface of the connecting surface part 8 and extends along a ring shape. That is, the first connecting groove 11 is annular in a circumferential direction of the igniter 1 in the connected state of Fig. 2. The opening width 11w of the first connecting groove 11 is constant along the entire circumference. As shown in Fig. 3B, the opening width is defined as a distance between two circumferential edges defining the opening of the first connecting groove 11, that is, as a distance between an inner circumferential edge 11a on the center side of the metal sleeve 2 and an outer circumferential edge 11b on the circumferential edge side of the metal sleeve 2. The inner circumferential edge 11a and the outer circumferential edge 11b are formed such that they cross an imaginary line extending in a radial direction (in the direction indicated by the arrow VL in Fig. 3A) with the igniter 1 in the connected state as a center along the entire circumference. The inner peripheral edge 11a and the outer peripheral edge 11b therefore have no part extending in a geometric sense parallel to the radial direction. As shown in Fig. 3B, the cross-sectional shape of the first connecting groove 11 is a substantially semicircular shape except for a part provided with the second connecting groove 12.

[0035] Furthermore, on the entire circumference of the inner peripheral edge 11a, the first connecting groove 11 has the first corner part 11c, which is formed by the upper surface of the connecting surface part 8 and an inner wall surface of the first connecting groove 11. At the first corner part 11c, an angle formed between the upper surface of the connecting surface part 8 and the inner wall surface of the first connecting groove 11 (specifically, an angle formed in the cross section of Fig. 3C, the angle θ1 formed between tangent lines tangential to the corresponding surfaces at an intersection point of the connecting surface part 8 and the inner wall surface of the first connecting groove 11 is an angle relatively close to 90 degrees, and preferably an angle in the range of 45 degrees to 90 degrees. When the angle of the first corner part 11c falls within this range, the forming processing for the first connecting groove 11 in the metal sleeve 2 can be more easily implemented, and a pressure-receiving surface described below is formed, which can receive a pressing force generated by the molding shrinkage of the synthetic resin material.

[0036] Furthermore, the second connecting groove 12 is a groove that opens in the inner wall surface of the first connecting groove 11 and extends along the annular shape of the connecting surface part 8 such that the opening part is located below the first corner part 11c. Specifically, in the cross section of the first connecting groove 11, the second connecting groove 12 opens adjacent to a central bottom part of the first connecting groove 11. Furthermore, the opening direction of the second connecting groove 12 corresponds to the opening direction of the first connecting groove 11. The opening direction is the direction orthogonal to an opening surface of the connecting grooves (a surface defined by the inner peripheral edge and the outer peripheral edge). Therefore, in the connected state of Fig. 2, the second connecting groove 12 is annular in the circumferential direction of the igniter 1 and is arranged to overlap the first connecting groove 11 in a depth direction of the first connecting groove 11.

[0037] Furthermore, the opening width 12w of the second connecting groove 12 is smaller than the opening width 11w of the first connecting groove 11 and is constant along the entire circumference. The definition of the opening width is the same as that of the first connecting groove 11. As shown in Fig. 3B, the opening width is defined as a distance between two peripheral edges of the opening of the second connecting groove 12, that is, a distance between an inner peripheral edge 12a on the center side of the metal sleeve 2 and an outer peripheral edge 12b on the peripheral edge side of the metal sleeve 2. The inner peripheral edge 12a and the outer peripheral edge 12b are formed so as to cross the imaginary line extending in the direction indicated by the arrow VL in Fig. 3A, respectively, extends over the entire circumferences. The inner peripheral edge 12a and the outer peripheral edge 12b therefore have no part extending in a geometric sense parallel to the radial direction. Furthermore, the inner peripheral edge 12a of the second connecting groove 12 is arranged outside the inner peripheral edge 11a of the first connecting groove 11, ie, on the peripheral edge side of the metal sleeve 2. The cross-sectional shape of the second connecting groove 12 has, as shown in Fig. 3 has a substantially semicircular shape.

[0038] Furthermore, on the entire circumference of the inner peripheral edge 12a, the second connecting groove 12 has the second corner part 12c, which is formed by the inner wall surface of the first connecting groove 11 and an inner wall surface of the second connecting groove 12. At the second corner part 12c, an angle formed between the inner wall surface of the first connecting groove 11 and the inner wall surface of the second connecting groove 12 (specifically, an angle formed in the cross section of Fig. 3C, the angle θ2 formed between tangent lines tangential to the corresponding surfaces at an intersection point of the inner wall surface of the first connecting groove 11 and the inner wall surface of the second connecting groove 12 is an angle relatively close to 90 degrees, and preferably an angle in the range of 90 degrees to 135 degrees. When the angle of the second corner part 12c falls within this range, forming processing for the second connecting groove 12 in the metal sleeve 2 can be more easily implemented, and a pressure-receiving surface described below is formed, which can receive a pressing force generated by mold shrinkage of the resin material.

[0039] As described above, on the connecting surface part 8 of the metal sleeve 2, the first connecting groove 11 and the second connecting groove 12 are arranged overlappingly in the axial direction of the metal sleeve 2, and their opening directions correspond to each other. Therefore, the area of ​​the connecting surface part 8 can be smaller than in a case where the first connecting groove 11 and the second connecting groove 12 are arranged in the radial direction indicated by the arrow VL. This allows the dimension of the metal sleeve 2 to be reduced in the radial direction.

[0040] Furthermore, the synthetic resin material is injected into the interior of the metal sleeve 2 along the axial direction of the metal sleeve 2 to integrate the igniter 1 with the metal sleeve 2 through the synthetic resin connecting part 3, wherein the two connecting grooves are arranged overlapping as described above, and the synthetic resin material enters the first connecting groove 11 and the second connecting groove 12 and then shrinks to the center side of the metal sleeve 2. Therefore, a pressing force generated by the shrinkage acts from the peripheral edge side to the center side of the metal sleeve 2. Here, as described above, the first corner part 11c is formed on the inner peripheral edge 11a of the first connecting groove 11 and the second corner part 12c is formed on the inner peripheral edge 12a of the second connecting groove 12. At the corner parts, the edges formed by the inner wall surfaces of the corresponding connecting grooves (iethe inner wall surface of the first connecting groove 11 at the first corner part 11c and the inner wall surface of the second connecting groove 12 at the second corner part 12c) with respect to the direction from the peripheral edge side to the center side of the metal sleeve 2 (the direction of the outline arrows in . Fig. 3C, ie the direction along the upper surface of the connecting surface part 8 in this embodiment) formed angles (θ1 and θ3 in Fig. 3) Preferably, angles in the range of 45 degrees to 90 degrees. With this configuration, the inner wall surfaces of the connecting grooves at the corresponding corner portions receive a shrinkage force of the injection-molded resin material, thereby improving the sealing performance between the resin connecting portion 3 and the metal collar 2. Furthermore, because these two corner portions are arranged at the connecting surface portion 8, an extremely high degree of sealing performance can be provided and the penetration of moisture from the outside into the igniter assembly 100 can be prevented.

[0041] The following describes the development of the sealing performance between the synthetic resin material and the metal sleeve 2 on the projection wall 10. The projection wall 10 is formed with a substantially tubular shape extending in the axial direction of the metal sleeve 2 and surrounds the igniter 1. As shown in Fig. 2, an inner peripheral surface, an outer peripheral surface, and a distal end surface of the protrusion wall 10 are also covered by the resin bonding part 3 integrating the igniter 1 and the metal collar 2. Thus, the protrusion wall 10 is clamped in its thickness direction to the center side of the metal collar 2 by the shrinkage of the resin material, and the resin bonding part 3 and the metal collar 2 are bonded more reliably.

[0042] As described above, with the igniter assembly 100 according to this embodiment, a size reduction of the metal sleeve 2 can be achieved, while at the same time, a relatively high degree of sealing performance can be achieved by the resin material between the igniter 1 and the metal sleeve 2. Furthermore, as described above, the opening directions of the first connecting groove 11 and the second connecting groove 12 can correspond to each other. Therefore, when the metal sleeve 2 is subjected to cutting processing for forming the respective connecting grooves, the process can be implemented more easily. Furthermore, even if the opening directions of the first connecting groove 11 and the second connecting groove 12 do not correspond to each other, only the corner parts, where a pressing force generated by the shrinkage of the injected resin material acts as described above, need to be formed on the inner peripheral edges of the respective connecting grooves. Second embodiment

[0043] With reference to Fig. 4, an igniter arrangement 100 according to a second embodiment is described below. Fig. 4A shows a state in a perspective cross-sectional view of the metal collar 2 used in the igniter assembly 100 along a cross section including an axial line. Fig. Fig. 4B shows a state in which the connecting surface part 8, on which a first connecting groove 21 and a second connecting groove 22 are provided, is partially enlarged. The right side in Fig. 4B corresponds to the center side of the metal sleeve 2, and the left side corresponds to the peripheral edge side of the metal sleeve 2.

[0044] In this embodiment, the first connecting groove 21 is a groove that opens in the upper surface of the connecting surface part 8 and extends along a ring shape. Thus, the first connecting groove 21 extends annularly in a circumferential direction of the igniter 1 in the connected state of Fig. 2. The opening width 21w of the first connecting groove 21 is constant along the entire circumference. Furthermore, the opening portion of the first connecting groove 21 is defined by an inner peripheral edge 21a on the center side of the metal sleeve 2 and an outer peripheral edge 21b on the peripheral edge side of the metal sleeve. The inner peripheral edge 21a and the outer peripheral edge 21b are formed to intersect the imaginary line extending in the radial direction indicated by the arrow VL with the igniter 1 in the connected state as a center over the entire circumferences.

[0045] Furthermore, as in Fig. As shown in FIG. 4B, the cross-sectional shape of the first connecting groove 21 is a substantially rectangular shape except for a portion provided with the second connecting groove 22. Therefore, at a first corner portion 21c formed on the inner peripheral edge 21a of the first connecting groove 21 over the entire circumference, an angle formed between the upper surface of the connecting surface portion 8 and an inner wall surface of the first connecting groove 21 is 90 degrees. Therefore, the forming processing for the first connecting groove 21 in the metal collar 2 can be implemented more easily, and a wall surface of the first corner portion 21c can receive a pressing force generated by the molding shrinkage of the resin material.

[0046] The second connecting groove 22 is a groove that opens on a bottom surface of the first connecting groove 21 such that the second connecting groove 22 extends along the annular shape of the connecting surface part 8 and the opening part is arranged below the first corner part 21c. Specifically, the second connecting groove 22 opens on the bottom surface of the first connecting groove 21 such that an outer peripheral edge 22b corresponds to the outer peripheral edge 21b of the first connecting groove 21 and an inner peripheral edge 22a is arranged outside the inner peripheral edge 21a of the first connecting groove 21, that is, on the peripheral edge side of the metal sleeve 2. Furthermore, the opening direction of the second connecting groove 22 corresponds to the opening direction of the first connecting groove 21. The opening direction is a direction orthogonal to the opening surface of the connecting grooves. Therefore, in the connected state of Fig. 2, the second connecting groove 22 is annular in the circumferential direction of the igniter 1 and is arranged to overlap the first connecting groove 21 in a depth direction of the first connecting groove 21.

[0047] Furthermore, the opening width 22w of the second connecting groove 22 is smaller than the opening width 21w of the first connecting groove 21 and is constant along the entire circumference. The inner peripheral edge 22a and the outer peripheral edge 22b of the second connecting groove 22 are formed to cross the imaginary line extending in the radial direction indicated by the arrow VL on the entire circumferences. The cross-sectional shape of the second connecting groove 22 is a rectangular shape similar to that of the first connecting groove 21. Therefore, at a second corner part 22c formed on the inner peripheral edge 22a of the second connecting groove 22 on the entire circumference, an angle formed between the inner wall surface (bottom surface) of the first connecting groove 21 and an inner wall surface of the second connecting groove 22 is 90 degrees.Therefore, a forming process for the second connecting groove 22 in the metal sleeve 2 is more easily implemented, and a wall surface of the second corner part 22c can receive a pressing force generated by mold shrinkage of the resin material.

[0048] In the metal boot 2 having the structure of this embodiment, the first connecting groove 21 and the second connecting groove 22 are arranged on the connecting surface part 8 so as to overlap in the axial direction of the metal boot 2, and the opening directions correspond to each other. This allows the dimension of the metal boot 2 to be reduced in the radial direction. Furthermore, the resin material is injected to integrate the igniter with the metal boot 2 via the resin connecting part 3, wherein the two connecting grooves are arranged so as to overlap as described above, and the resin material enters the first connecting groove 11 and the second connecting groove 12 and then shrinks toward the center side of the metal boot 2. At this time, a pressing force generated by the shrinkage acts on the first corner part 21c and the second corner part 22c, and the sealing performance between the resin connecting part 3 and the metal boot 2 is increased.Furthermore, with the two corner parts arranged on the connecting surface part 8 as described above, a high degree of sealing performance can be provided and penetration of moisture from the outside into the igniter assembly 100 can be prevented. Other embodiment

[0049] With reference to Fig. 5, a metal sleeve 2 applicable to the igniter assembly 100 according to other embodiments is described below. Fig. In the embodiments shown in Fig. 5, a first connecting groove and a second connecting groove are indicated by reference numerals 31 and 32, respectively. Furthermore, an inner peripheral edge, an outer peripheral edge, a first corner part, and an opening width of the first connecting groove 31 are indicated by reference numerals 31a, 31b, 31c, and 31w, respectively. An inner peripheral edge, an outer peripheral edge, a second corner part, and an opening width of the second connecting groove 32 are indicated by reference numerals 32a, 32b, 32c, and 32w, respectively. The first connecting groove 31 is a groove that opens in the upper surface of the connecting surface part 8 and extends along an annular shape thereof. Furthermore, the inner peripheral edge 31a and the outer peripheral edge 31b are formed so as to cross the imaginary line extending in the radial direction indicated by the arrow VL with the igniter 1 in the connected state as a center over the entire circumferences, respectively.Furthermore, the second connecting groove 32 is a groove opening in an inner wall surface (bottom surface) of the first connecting groove 31 such that the second connecting groove 32 extends along the annular shape of the connecting surface part 8 and its opening part is located below the first corner part 31c. Furthermore, the inner peripheral edge 32a and the outer peripheral edge 32b are formed to cross the imaginary line extending in the radial direction indicated by the arrow VL with the igniter 1 in the connected state as a center over the entire circumferences, respectively.

[0050] The Fig. The three execution modes shown in Figure 5 are described in detail below. In the embodiment of Fig. 5A, the first connecting groove 31 and the second connecting groove 32 are formed with a rectangular cross section. Furthermore, the second connecting groove 32 opens in the bottom surface of the first connecting groove 31 such that the outer peripheral edge 32b of the second connecting groove 32 and the outer peripheral edge 31b of the first connecting groove 31 correspond to each other, and the inner peripheral edge 32a of the second connecting groove 32 and the inner peripheral edge 31a of the first connecting groove 31 correspond to each other. At this time, the opening width 31w of the first connecting groove 31 and the opening width 32w of the second connecting groove 32 correspond to each other. However, the groove width excluding the opening part of the second connecting groove 32 is formed larger than the opening width 32w. Also in this embodiment, the angles at the first corner part 31c and the second corner part 32c are both equal to 90 degrees.Therefore, wall surfaces of the corresponding angle parts can receive a pressing force generated by casting shrinkage of the resin material.

[0051] In the embodiment of Fig. 5B, the first connecting groove 31 is formed with a rectangular cross section, and the second connecting groove 32 is formed with a semicircular cross section. Furthermore, the second connecting groove 32 opens in the bottom surface of the first connecting groove 31, so that the outer peripheral edge 32b of the second connecting groove 32 and the outer peripheral edge 31b of the first connecting groove 31 correspond to each other, and the inner peripheral edge 32a of the second connecting groove 32 is located outside the inner peripheral edge 31a of the first connecting groove 31, that is, on the peripheral edge side of the metal sleeve 2. Also in this embodiment, the angle at the first corner part 31c is 90 degrees, and the angle at the second corner part 32c is close to 90 degrees. Therefore, wall surfaces of the respective angle parts can receive a pressing force generated by mold shrinkage of the resin material.

[0052] In the embodiment of Fig. 5C, the first connecting groove 31 is formed with a sector-shaped (quadrant-circular) cross section, and the second connecting groove 32 is formed with a rectangular cross section. Furthermore, the second connecting groove 32 opens in the inner wall surface of the first connecting groove 31 such that the outer peripheral edge 32b of the second connecting groove 32 is located inside the outer peripheral edge 31b of the first connecting groove 31, that is, on the center side of the metal sleeve 2, and the inner peripheral edge 32a of the second connecting groove 32 is located outside the inner peripheral edge 31a of the first connecting groove 31, that is, on the outer peripheral side of the metal sleeve 2. Also in this embodiment, the angle at the first corner part 31c is 90 degrees, and the angle at the second corner part 32c is close to 90 degrees. As a result, wall surfaces of the respective angle parts can receive a pressing force generated by mold shrinkage of the resin material.

[0053] In the above-described embodiments, a case is described in which a single igniter is fixed to a single metal collar by the synthetic resin material. However, the invention can also be applied to a case in which two igniters are integrated into a single metal collar by the synthetic resin material, such as in Fig. 25 of JP 2001-97173 A. Furthermore, for the embodiments of the invention, it is important that the resin connection part enters the first connection groove and the second connection groove, and a state in which the first corner part and the second corner part are pressed by the resin connection part is maintained. As long as the first corner part and the second corner part are pressed by the resin connection part, the first connection groove and the second connection groove are not limited to the cross-sectional shapes described above. [List of reference symbols] 1 detonator 2 metal cuffs 3 Resin connecting part 8 Connecting surface part 10 projection wall 11, 21, 31 first connecting groove 11a, 12a, 21a, 22a, 31a, 32a inner peripheral edge 11b, 12b, 21b, 22b, 31b, 32b outer peripheral edge 11c, 21c, 31c first corner section 12, 22, 32 second connecting groove 12c, 22c, 32c second corner part 100 igniter arrangement 103 housings 104 Gas discharge opening 105 Gas generating agents

Claims

[1] Igniter assembly (100), comprising: an igniter (1) configured to cause the combustion of an ignition charge with an ignition current supplied via an electrically conductive pin (5) and to eject a combustion product, a metal sleeve (2) arranged around the igniter (1), and a synthetic resin connecting part (3) configured to integrally connect the igniter (1) and the metal sleeve (2), which are non-contact with each other, by a synthetic resin material and to establish a connected state in which the igniter (1) and the metal sleeve (2) are connected such that a part of the electrically conductive pin (5) to which a voltage can be applied is exposed, wherein the metal sleeve (2) comprises: a connecting surface part (8) having an annular surface surrounding a periphery of a part of the igniter (1) in the connected state, the annular surface being covered by the synthetic resin connecting part (3) and being brought into contact with the synthetic resin connecting part (3), a first connecting groove (11, 21, 31) opening in the annular surface of the connecting surface part (8) in a vertical direction of the igniter (1) and extending circularly around the igniter center, wherein the first connecting groove (11, 21, 31) includes a first inner peripheral edge (11a, 21a, 31a) in an opening, and the first inner peripheral edge (11a, 21a, 31a) has a first corner part (11c, 21c, 31c) formed on the entire circumference of the first inner peripheral edge (11a, 21a, 31a) between the annular surface and an inner wall surface of the first connecting groove (11, 21, 31) and having a first predetermined angle (θ1), and characterized by , that a second connecting groove (12, 22, 32) is formed in the first connecting groove (11, 21, 31), which opens in the inner wall surface of the first connecting groove (11, 21, 31) under the first corner part (11c, 21c, 31c) also in the vertical direction of the igniter (1) and extends annularly in the circumferential direction of the igniter (1), wherein the second connecting groove (12, 22, 32) has a second inner peripheral edge (12a, 22a, 32a) in an opening of the second connecting groove (12, 22, 32), and the second inner peripheral edge (12a, 22a, 32a) has a second corner part (12c, 22c, 32c) which is formed on the entire circumference of the second inner peripheral edge (12a, 22a, 32a) between the inner wall surface of the first connecting groove (11, 21, 31) and an inner wall surface of the second connecting groove (12, 22, 32) and has a second predetermined angle (θ3), wherein the connected state is established in which the synthetic resin connecting part (3) has entered into the first connecting groove (11, 21, 31) and the second connecting groove (12, 22, 32), and the synthetic resin connecting part (3) presses the first corner part (11c, 21c, 31c) and the second corner part (12c, 22c, 32c). [2] Igniter assembly (100) according to claim 1, wherein: a bottom part of the second connecting groove (12, 22, 32) is deeper than a bottom part of the first connecting groove (11, 21, 31), and the second inner peripheral edge (12a, 22a, 32a) of the opening part of the second connecting groove (12, 22, 32) is arranged outside the first inner peripheral edge of the opening part of the first connecting groove (11, 21, 31) with the igniter (1) in the connected state as a center. [3] Igniter assembly (100) according to claim 1 or 2, wherein the opening direction of the opening part of the second connecting groove (12, 22, 32) corresponds to the opening direction of the opening part of the first connecting groove (11, 21, 31). [4] The igniter assembly (100) according to any one of claims 1 to 3, wherein the first predetermined angle (θ1) and the second predetermined angle (θ3) are both 90 degrees. [5] Igniter assembly (100) according to one of claims 1 to 4, wherein the first connecting groove (21, 31) and the second connecting groove (22, 32) are formed with a rectangular cross section. [6] Igniter assembly (100) according to claim 5, wherein the groove width except for the opening of the second connecting groove (32) is formed larger than the opening width (31w) of the first connecting groove (31). [7] Igniter assembly (100) according to one of claims 1 to 4, wherein the first connecting groove (31) is formed with a rectangular cross section and the second connecting groove (32) is formed with a semicircular cross section. [8] Igniter assembly (100) according to one of claims 1 to 4, wherein the first connecting groove (31) is formed with a sector-shaped cross section and the second connecting groove (32) is formed with a rectangular cross section. [9] Gas generator, comprising: the igniter arrangement (100) according to one of claims 1 to 8, a housing (103) configured to accommodate the igniter assembly (100), the housing (103) being filled with a gas generating agent (105) whose combustion is caused by actuation of the igniter (1) in the igniter assembly (100), and a discharge port (104) configured to discharge a combustion gas generated by the combustion of the gas generating agent (105) to the outside, wherein the discharge port (104) is provided in the housing (103).

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