WO2001002793A1

WO2001002793A1 - Squib and method of manufacture thereof

Info

Publication number: WO2001002793A1
Application number: PCT/JP2000/004338
Authority: WO
Inventors: Junya Amano; Hiroshi Hori
Original assignee: Nippon Kayaku Kabushiki-Kaisha
Priority date: 1999-07-02
Filing date: 2000-06-30
Publication date: 2001-01-11
Also published as: CZ20014541A3; KR20020025178A; EP1209436A1; TW482889B; JP2001021293A

Abstract

The invention provides a squib used with a gas source to operate a vehicular safety device such as a seat belt pretensioner and an air bag. The squib includes a cup (2), ignition agent (3) loaded in the cup (2), a plug (4) for stopping an opening of the cup (2), two electrode pins (5,6) extending through the plug (4), and a bridge wire (7) connected between the two electrode pins (5,6) in the cup (2) and adapted to ignite when electrically energized. The two electrode pins (5,6) extend through the plug (4) and form projections (23) on the cup side of the plug (4). The bridge wire (7) is connected between the projections (23) of the electrode pins (5,6). The bridge wire (7) and the projections (23) are buried in the ignition agent (3), and the bridge wire (7) and the ignition agent (3) are sealed in the cup (2) in such a manner that they keep a predetermined contact pressure acting between them.

Description

W

Specification

Squib and method of manufacturing squib

The present invention relates to a squib used for a gas generator that operates an occupant safety protection device such as an automobile seat belt pretensioner or an airbag. Background art

A seat belt pretensioner or an airbag is known as a device that protects an occupant from an impact caused by a car collision. These pretensioners are operated by a large amount of gas introduced from the gas generator to protect occupants. Further, the gas generator is provided with a type, a gas generating agent, etc., and ignites and burns the gas generating agent by igniting the squib at the time of collision to rapidly generate a large amount of gas.

As an example of a squib used for a gas generator, there is a squib in which an ignition powder is stored and an embolus which is inserted into the cup and seals the ignition powder is formed of plastic resin or the like. Further, the embolus has two electrode pins penetrating the embolus. Each of these electrode pins protrudes into the cup and electrically connects the bridge to the tip. The electric wire is covered with an ignition ball in contact with the ignition charge. The igniter ball is made of a material with excellent ignition sensitivity. It ignites by the heat generated by the bridge and ignites the ignition charge.

This squib is attached to the gas generator and is energized by a collision signal from a collision sensor, causing the bridge wire to generate heat. The heated wire ignites the ignition ball, and then ignites and burns the igniting charge. Then, the gas generating agent is ignited and burned by the generated pressure and heat generated by the burning of the igniting agent. The ignition method used in conventional resin squeegees is stable ignition sensitivity. For the purpose of igniting, the ignition ball is ignited by the heat of the bridge wire, and the ignition charge is subsequently ignited.

Therefore, in the conventional resin squib, it is necessary to cover the electric wire with an ignition ball. This coating of the ignition ball is usually performed by diving the electric wire several times, resulting in an increase in manufacturing cost / operating cost. In addition, ignition balls usually contain harmful heavy metals such as lead, and squibs that do not use harmful substances have been demanded from recent environmental awareness.

Also, in recent years, there has been a strong demand for lower cost for seat velvet pretensioners and gas generators for airbags, and accordingly, lower squib cost has also been required.

An object of the present invention is to provide an environmentally friendly squib while reducing costs. Disclosure of the invention

The squib of the present invention relates to a squib used for a gas generator that operates an occupant protection device such as an automobile seat belt pretensioner or an airbag. The squib of the present invention comprises: a cup; an igniting agent charged in the cup 內; an embolus for closing an opening of the cup; two electrode pins inserted into the embolus; and the two electrodes in the cup. It includes a bridge line connected between the electrode pins and ignited when energized.

The two electrode pins are inserted into the embolus so as to form a protrusion projecting from one end of the embolus on the cup side. The electric bridge is connected between the protruding portions of the electrode pins.

The power lines and the protrusions are embedded in the ignition powder. The electron beam and the igniting agent are brought into contact with each other under a predetermined contact pressure. Enclosed in the cup.

Further, the method for manufacturing a squib of the present invention relates to a method for manufacturing a squib used for a gas generator for operating an occupant protection device such as a seat belt pretensioner wear bag of an automobile.

The method for manufacturing a squib of the present invention comprises the steps of loading a resin between each electrode pin and the outer periphery thereof except for both ends of two parallel electrode pins to form an embolus, and forming one end of the embolus. Connecting the two ends of the bridge wire to the protruding portions of the respective electrode pins protruding from the plug, inserting the bridge side of the embolus into the power cup, and connecting the bridge wire and the protruding portion inside the cup. Embedding the ignition plug into the cup so that the bridge and the ignition powder are sealed in the cup under a predetermined contact pressure with each other. And the step of causing

According to the present invention having the above configuration, since the electric wire is embedded in the ignition charge, the contact area between the electric bridge wire and the ignition charge can be increased. Then, when an igniting agent having a component that is ignited by the heat of the bridge wire is used, the igniting agent around the bridge wire is ignited by the heat of the electric wire due to energization of each electrode pin. can do. Since the electric bridge wire and the igniting agent are sealed in the power switch in a state where a predetermined contact pressure acts on each other, the igniting agent is stably ignited even if only the electric wire is heated. can do.

Since the electric wire is connected between the projecting portions of the electrode pins and is located at a position protruding from the embolus, in the assembling step of inserting the embolus into the forceps and fitting the embolus and the cup, It can be adjusted to obtain a predetermined contact pressure.

Further, at the tip of the protruding portion of each electrode pin, a flat welding surface is arranged along the axis of each electrode pin, leaving a predetermined constant gap h and arranged substantially on the same plane. It is provided continuously, and these welding surfaces are It is preferable that both ends of the storage bridge are connected to each other.

According to the above configuration, the substantial length of the bridge wire is determined by the gap h between the welding surfaces. If the connection position of the bridge is within the welding surface, the substantial length of the bridge is h, and a substantially predetermined length h of the electrode wire can be obtained. Therefore, the power line can be easily connected to each electrode pin without increasing the accuracy of the connection position of the power line, and a predetermined resistance value of the power line can be secured. In addition, it is preferable that the foremost part of the projecting portion of each of the electrode pins is folded back so as to cover the connecting portion of the electric wire. With this configuration, it is possible to prevent the connecting portion of the electric bridge line from coming off due to contact resistance with the ignition agent in the step of embedding and embedding the electric wire in the ignition agent.

Further, it is preferable that the electric bridge wire is connected to the projecting portions in a relaxed state in which no tension acts between the projecting portions of the respective electrode pins, and then sealed in the cup.

With this configuration, it is possible to reduce the contact resistance of the igniting agent with respect to the electric wire in the process of burying the electric wire in the igniting agent and embedding it.

Then, the loading density of the ignition powder in the forceps is 2 mg / mm ³ or more and dmg Zmm ³ or less so that the electric wire and the ignition powder are sealed in a state where a predetermined contact pressure acts on each other. Preferably, it is adjusted to the range of. Further, it is preferable that the igniting agent has a component that ignites by the heat generated by the electric bridge wire, and is in a powdery or granular form. In addition, the dressing preferably has zirconium as a component. As a result, the ignition charge can be stably ignited only by the heat generated from the power line. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a partial sectional view of a squib of the present invention as viewed from the front. No. 2 The figure is an exploded view of the squib shown in FIG. FIG. 3 is a partial sectional view of the squib embolus shown in FIG. 1 as viewed from above. FIGS. 4 (a), 4 (b), 4 (c), and 4 (d) show a method of manufacturing a squib. FIGS. 4 (a) and 4 (b) ) Is a front view, FIG. 4 (c) is a cross-sectional view as viewed from above, and FIG. 4 (d) is a partial cross-sectional view as viewed from the front. FIGS. 5 (a), 5 (b), 5 (c) and 5 (d) show the method of manufacturing the squib, and FIGS. 5 (a) and 5 (b) ), Fig. 5 (c) is a partial sectional view from the front, and Fig. 5 (d) is a partial sectional view from the top. FIGS. 6 (a), 6 (b), and 6 (c) are views showing a method for manufacturing a squib, and are partial cross-sectional views as viewed from the front. Fig. 7 (a) is a diagram showing the connection of the electric bridge lines in a conventional squib. FIG. 7 (b) is a diagram showing a connection state of the electric bridge line in the squib of the present invention. FIG. 8 is a partial sectional view of another squib of the present invention viewed from the front. FIG. 9 is an exploded view of the squib shown in FIG. FIG. 10 is a partial sectional view of a gas generator using the squib of the present invention as viewed from the front. BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment)

The first embodiment will be described with reference to FIGS. 1 to 3 and FIGS. 7 (a) and 7 (b).

The squib 1 shown in FIG. 1 includes a cup 2, an ignition charge 3, an embolus 4, two electrode pins 5 and 6, and an electric wire 7. In addition, the squib 1 is designed to reduce the manufacturing cost by forming the cup 2 and the plug 4 from resin.

The cup 2 is formed by a bottom portion 2b and a cylindrical portion, and is ignited. Drug 3 is loaded. Further, a convex shape 8 is formed along the inner circumference at the end of the cup 2 on the opening 2a side. This is because when the embolus 4 is inserted into the cup 2, the convex shape 8 of the forceps 2 is fitted into the mounting groove 19 provided at a predetermined position of the embolus 4, and Is provided to maintain a predetermined position in the force switch 2.

Examples of the cup 2 include PBT (polybutylene terephthalate), PET (polyethylene terephthalate), PA6 (nylon 6), PA 66 (nylon 66), PPS (polyphenylene sulfide), and P PO (polyphenylene sulfide). It is composed of a resin containing a reinforcing material such as glass fiber in a resin such as poly (phenylene oxide).

The embolus 4 is composed of a cylindrical portion 16 inserted into the cup 2, and a flange portion 18 protruding in the diameter increasing direction at one end of the cylindrical portion 16 and continuing to the cylindrical portion 16. You. An annular mounting groove 19 into which the convex shape 8 of the cup 2 is fitted is formed on the outer periphery of the cylindrical portion 16. Further, the flange portion 18 has a tapered surface 21 whose diameter decreases toward the opposite side to the cylindrical portion 16. The embolus 4 is made of, for example, a resin such as PBT, PET, PA6, PA66, PSS, PPP or the like containing a reinforcing material such as glass fiber.

The two electrode pins 5 and 6 are arranged in parallel with the axis of the column 16 of the embolus 4, penetrate the embolus 4 內, and protrude from both ends of the embolus 4. Each of the electrode pins 5 and 6 has a curved portion 45 that curves outward in the flange portion 18. Each of these electrode pins 5, 6 is formed of a single conductive round bar made of stainless steel, an alloy of iron and nickel, or the like.

Further, a welding surface 24 is provided continuously at the tip of the projecting portion 23 of each of the electrode pins 5 and 6 projecting in the axial direction from the other end of the cylindrical portion 16. These welding surfaces 24 are planes along the axis of each of the electrode pins 5 and 6, They are arranged side by side on a substantially same plane with a predetermined constant gap h. Such a plane can be easily formed by crushing the tips of the protruding portions 23 of the electrode pins 5 and 6 in the radial direction by press molding or the like.

Each of the welding surfaces 24 is formed so that the electric bridge line 7 vertically crosses the gap h between the welding surfaces 24 at the tips of the protrusions 23 in a relaxed state in which substantially no tension acts. Spanned between. Then, as shown in FIG. 3, while maintaining the slackened state in which substantially no tension acts on the electric bridge wire 7, the respective ends are welded to the respective welding surfaces 24 by welding or the like. Welded. The welded portion 25 of the electric bridge wire 7 is covered by a folded portion 24 a that is a tip of the welding surface 24, which is also the tip of the projecting portion 23. As described above, if the bridge 7 is connected to the welding surface 24, as shown in FIG. 7 (b), the substantial length of the wiring 7 is determined by the gap between the welding surfaces 24. The distance is determined by h. Regardless of the position in the welding surface 24 where the connecting position of the bridge wire 7 bridged between the welding surfaces 24 vertically crosses the gap h, all the lengths of the substantial The length h is obtained, and a substantially predetermined length h of the electrode wire can be obtained without increasing the accuracy of the connection position of the power line 7. Accordingly, the electric wire 7 can be easily connected to each of the electrode pins 5 and 6, and a predetermined resistance value of the electric wire 7 can be secured.

On the other hand, as shown in Fig. 7 (a), when connection is made to the cut surfaces of the electrode pins 5 and 6, respectively, the distance between the electrode pins 5 and 6 depends on the welding position of the bridge wire 7. L l and L 2 are different. Therefore, the substantial length of the bridge wire 7 is also different, and unless the welding positions at both ends of the bridge wire 7 are accurately adjusted, the substantially predetermined length of the bridge wire 7 cannot be obtained.

In addition, as shown in FIG. 2, when the electric bridge wire 7 is connected to the welding surface 24 of each of the protrusions 23 in a loose state where no tension acts. In the step of burying the electric wire 7 in the ignition charge 3 and embedding it, the contact resistance of the ignition charge 3 to the insertion wire 7 can be reduced.

When the welded portion 25 of the bridge wire 7 is covered by the folded portion 24 a at the end of each welding surface 24, the wire 7 is sunk into the igniting charge 3 and embedded therein. In the process, the welding portion 25 of the power line 7 can be prevented from coming off due to contact resistance with the igniter 3. -Then, the bridge wire 7 generates heat by energizing the electrode pins 5 and 6 shown in FIG. The resistance value [Ω / mm] of the electric wire 7 per unit length is determined to be a predetermined value so that this calorific value becomes a calorific value capable of igniting the ignition charge 3.

The predetermined resistance value [QZmm] is determined by the relationship between the cross-sectional shape and thickness of the electrode wire 7, the current value [A] supplied to the electrode pins 5, 6, and the like. Further, the material of the electric wire 7 has such a strength that the electric wire 7 is not cut when the plug 4 is inserted into the cup 2 while having the predetermined resistance value [ΩΖηιιη]. Material is selected. For example, the bridge wire 7 is formed of nickel and chrome alloy wire having excellent heat generation and strength.

The electric wire 7 is embedded in the igniting charge 3 so that the contact area with the igniting charge 3 is increased to efficiently ignite the igniting charge 3.

As the igniting powder 3 in the cup 2, dinoreconium (Zr), tundane stainless steel (W), potassium perchlorate (KCIO ,,) was used as a component, and fluorine rubber, nitrocellulose, or the like was used as a binder. Preferably, one is used. The composition ratio of zirconium, tungsten, and potassium perchlorate is determined so that the heat generated by the bridge 7 can ignite sufficiently. For example, Zr: W: KC 1Ο ,, = 3: 3.5: 3.5 by weight ratio. In addition, the ignition charge 3 is used to increase the contact area with the electric bridge line 7 and to prevent the electric bridge line 7 from being cut when inserting the embolus 4 into the forceps 2. It is preferably in the form of granules or granules.

A pretensioner that protects the occupants of a car must be activated within a few milliseconds (ms) after a car collision. For this reason, a squib that ignites and burns a gas generating agent in a gas generator also needs to have the sensitivity to ignite within a few milliseconds (ms). Therefore, by setting the charging density of the igniting agent loaded in the cup 2 to 2 mg / mm ^{: i} or more and dmgZmm ³ or less, the predetermined contact pressure between the bridge bridge 7 and the igniting agent 3 is obtained. By sealing the battery in a state in which igniting occurs, the structure was such that the ignition current could be stably ignited by energizing 'current value (A) x several milliseconds (ms)' to the bridge wire.

Meniwa the loading density of the ignition powder was a 2 mg / mm ³ or more 4MgZmm ³ or less, 1 5 mm ³ or more spatial volume within the cup 1 20 mm ³ or less, the ignition agent amount to a 5 Omg than 48 Omg less preferable. In addition, it is preferable that the bridge wire has a diameter of ψ20 m or more and 29 / m or less, and a length of the wire is 0.5 or more and 1.2 mm or less.

When the bridge wire 7 is sunk into the igniting charge 3 together with the protruding portion 23, the cutting of the tamping wire 7 is effective if the loading density (apparent specific gravity) of the igniting charge ³ is 1.3 mgZmm ³ or less. Can be prevented. Then, after submerge the bridge wire 7 in igniting agent 3, further by advancing the embolic 4 in the cup 2, the high loading density of the ignition powder 3 to 2m GZmm ³ or more 4MgZmm ³ below Umate optimum Then, raise the embolus 4 to SmgZmrn ³ and fit it into the cup 2 to maintain that state.

These specific conditions make it possible to guarantee a few milliseconds, which is the operation time required for the operation of the gas generator of the occupant protection device such as a pretensioner.

In the squib having the above configuration, when current is passed between the electrode pins 5 and 6, the electric bridge wire 7 generates heat within several milliseconds (ms). Ignition only by this heat Drug 3 ignites stably and burns. Then, the internal pressure of the power cup 2 increases due to the combustion of the ignition charge 3, and the bottom 2b of the cup 2 bursts. The flame of pyrotechnic charge 3 blows out of the squib into the gas generator.

Thus, the squib of the present invention can ignite and burn the igniting charge 3 without providing an ignition ball containing a harmful substance to the railway bridge 7. Therefore, there is no need to provide ignition balls containing harmful substances, so low cost and environmentally friendly squibs have been provided.

Next, a method for manufacturing the squib 1 of the present invention will be described with reference to FIGS. 4 to 6. FIG.

The squib i of the present invention is manufactured by performing the following steps. In FIGS. 4 to 6, members having the same functions as those shown in FIGS. 1 to 3 are denoted by the same reference numerals.

(1) forming two electrode pins;

As shown in FIG. 4 (a), one conductive rod 40 made of stainless steel or an alloy of iron and nickel is prepared. The conductive rod 40 is bent into a U-shape by press molding or the like. Two parallel electrode pins 5, 6 having a straight portion and a bent portion 46 are formed. One end of each of the electrode pins 5, 6 remains connected by a U-shaped bent portion 46.

Further, a symmetrical curved portion 45 is formed on a part of the linear portion of each of the electrode pins 5 and 6 by breath molding or the like. In this manner, two parallel electrode pins 5, 6 having the curved portion 45 and the first and second linear portions 5a, 6a, 5b, 6b sandwiching the curved portion 45 are provided. Is formed. The electrode pins 5, 6 are still connected by a U-shaped bend 46.

(2) forming an embolus 4;

As shown in FIGS. 4 (b) and 4 (c), the embolus 4 It is formed by using two molds 41 and 42 having continuous first and second molding spaces 43 and 44 corresponding to the cylindrical portion 16 and the flange portion 18 of FIG.

The first linear portions 5a, 6a of the electrode pins 5, 6 are arranged in parallel along the axis of the first mold space 43. The curved portion 45 of each of the electrode pins 5, 6 is arranged in the second mold space 44. Ends of the first and second linear portions 5a, 6a, 5b, 6b of the electrode pins 5, 6 are projected from the first and second mold spaces 43, 44. In this state, the resin is injected into the first and second mold spaces 43 and 44 and loaded.

Subsequently, after the resin in each of the molds 41 and 42 is cured, the electrode pins 5 and 6 and the cured resin are peeled off from each of the molds 41 and 42. Then, an embolus 4 as shown in Fig. 4 (d) is obtained. Each of the electrode pins 5, 6 penetrates through the embolus 4 and protrudes from both ends, and is integrated with the embolus 4.

(3) forming a welding surface 24 on each of the electrode pins 5 and 6;

As shown in FIG. 5 (a), the bent portions 46 on the first linear portions 5a, 6a side of the electrode pins 5, 6 projecting from the cylindrical portion 16 of the embolus 4 are cut, and are independent from each other. Form each electrode pin 5,6. At this time, the bent portion 46 is cut leaving a length capable of forming the welding surface 24 at the tip of the protruding portion 23 of each of the electrode pins 5 and 6 protruding from the cylindrical portion 16 of the embolus 4.

Subsequently, as shown in FIG. 5 (b), the tip of each protruding portion 23 is crushed in the radial direction by press molding or the like to form a welding surface 24 along the axis of each of the electrode pins 5 and 6. At this time, the accuracy of the surface roughness and the parallelism of the welding surfaces 24 is ensured so that the welding surfaces 24 are arranged on the same plane with a predetermined gap h therebetween.

(4) welding the bridge 7; As shown in FIG. 5 (c), both ends of the bridge wire 7 are welded to the welding surface 24 at the tip of each protrusion 23 by welding or the like.

The electric bridge wire 7 is bridged between the welding surfaces 24 so as to vertically traverse the gap h between the welding surfaces 2, and in a relaxed state where substantially no tension acts, both ends thereof are It is welded to the welding surface 24 of the projection 23.

At this time, since the respective welding surfaces 24 are arranged so as to be arranged on the same plane with a predetermined gap h therebetween, the welding wire 24 can be welded to any position on the welding surface 24. The actual length is the same.

For example, the wire bridge 7 is welded to a position on the welding surface 24 such that the wire bridge 7 projects from the end of the embolus 4 by 0.5 to 4.0 mm.

Further, as shown in FIG. 5 (d), the tip of the welding surface 24 of each projection 23 is folded back so as to cover the welded portion 25 of the electric bridge line 7. Then, the welded portion 25 of the electric wire 7 is wrapped by the folded portion 24a.

(5) Step of embedding the electric wire 7 and the projecting portion 23 in the igniting charge 3; As shown in FIG. 6 (a), prepare the cup 2 containing the igniting charge 3. The cup 2 is formed at the same time as each of the above steps or in advance in a cup shape using a resin material such as PBT, PET, PA6, PA66, PPS, and PPO containing a reinforcing material such as glass fiber. The igniting agent 3 is stored in the cup 2 in a non-pressurized state using a powdered or granulated material.

Next, as shown in FIG. 6 (b), the cylindrical portion 16 side of the embolus 4 is inserted into the cup 2, and each of the projecting portions 23 and the bridge wire 7 is immersed in the ignition charge 3. And embed.

At this time, since the welded portion 25 of the bridge wire 7 is wrapped by the folded portion 24 a of the welding surface 24, the welding of the bridge wire 7 may come off due to frictional resistance with the igniter 3. Nare,

After embedding each projecting part 23 and electric bridge line 7 in the ignition charge 3, the circle of emboli 4 Charge the column 16 into the cup 2.

(6) fitting the embolus 4 into the cup 2;

As shown in FIG. 6 (b), the embolus 4 is further pushed into the bottom 2b side of the cup 2 to gradually increase the loading density of the powdery or granular ignition powder 3. At this time, since the electric bridge と共に has a projecting shape in which the electric bridge 7 protrudes from the embolus 4 together with the respective projecting parts 23, the contact with the igniting agent 3 is made within the power switch 2. The pressure is gradually increased. In addition, since the bridge wire 7 is installed between the electrode pins 5 and 6 in a slack state where the tension is not applied to the bridge wire 7, the bridge wire 7 is pushed into the cup 2 and rises to the extent of the contact pressure. Therefore, the bridge 7 will not be cut.

Then, as shown in FIG. 6 (c), the convex shape 8 of the cup 2 is fitted into the mounting groove 19 of the embolus 4. The embolus 4 is maintained in a predetermined position on the cup 2. At this time, the charging density of the igniting agent 3 in the cup 2 becomes a desired charging density, and the electric wire 7 comes into contact with the igniting agent 3 at a desired contact pressure.

Thus, the squib 1 in which the embolus 2 and the cup 2 are integrated is assembled.

Note that, in the squib of the present invention, it is not always necessary to adopt a structure in which the electric bridge 7 and the ignition charge 3 are sealed in a state where a predetermined contact pressure is generated. For example, by changing the composition of the ignition charge 3 and increasing the ignition sensitivity, the ignition charge 3 is stabilized by the current of (A) X several milliseconds (ms) for the electric wire 7. If it can be ignited, it is not necessary to seal the power line 7 and the igniting charge 3 at a predetermined contact pressure with each other.

Although the squib 1 of the present invention uses the cup 2 made of resin, for example, a metal cup, a cup having a double structure made of metal and resin, or the like can be used. Further, in the squib 1 of the present invention, the welding portion 2 of the electric bridge wire 7 is folded by folding back the tip 24 a of the welding surface 24 which is also the tip of the projecting portion 23 of each of the electrode pins 5 and 6. Although it is a configuration that protects the welding wire 5, if the bridge wire 7 can sufficiently withstand the contact resistance and contact pressure with the igniting agent 3, it is not always necessary to turn the tip of the welding surface 24.

(Second embodiment)

The second embodiment will be described with reference to FIGS. 8 and 9. In FIGS. 8 and 9, members having the same functions as those shown in FIGS. 1 and 2 are denoted by the same reference numerals.

8 and 9 are different from FIGS. 1 and 2 in the shapes of the cup 71 and the embolus 72.

The cup 71 of the squib 31 has a cylindrical portion 71c and a stepped portion 71d extending from the cylindrical portion 71c while being larger in diameter than the cylindrical portion 71c on the opening 7la side. I have. An annular mounting groove 32 is formed in the inner periphery of the cylindrical portion 71c, and a thin rupture portion 33 is formed in the bottom portion 71b. The cylindrical portion 7 1 c has an inner surface along a contour of a cylindrical portion 7 2 a of an embolus 72 described later, and the stepped portion 7 1 d has a ring of a flange portion 72-b of an embolus 72 described later. It has an inner surface.

The embolus 72 of the squib 31 is a stepped cylindrical body that closely contacts the contour of the inner surface of the stepped cup 71. The embolus 72 is composed of a cylindrical portion 72 a and a flange portion 72 b protruding at one end of the cylindrical portion 72 a in the radially expanding direction and continuing with the cylindrical portion 72 a. A ridge 34 fitted into the mounting groove 32 of the cup 71 is provided along the outer periphery of the cylindrical portion 72a.

Squib 31 is assembled as follows. The bridge 7 side of the embolus 72 is inserted into the cup 71. Embolus 7 2 Protruding from the column 7 2 a The cylindrical part 72 a of the embolus 72 is inserted into the cup 71 while the projecting part 23 and the bridge wire 7 are sunk into the ignition powder 3 of the cup 71. Subsequently, the plug 72 is pushed into the bottom 71 b side of the cup 71 to gradually increase the charge density of the powdery or granular igniter 3. When the embolus 72 reaches a predetermined position in the cup 71, that is, when the ignition charge reaches a predetermined loading density, the ridges 34 of the embolus 72 are inserted into the mounting grooves 32 of the cup 71. Fit in. The stepped portion 71d of the force cap 71 closely contacts the flange portion 72b of the plug 72, and the cylindrical portion 71c of the cup 71 is connected to the cylindrical portion 72a of the plug 72. It will be in close contact. Thus, the cup 71 and the embolus 72 are engaged with each other at a predetermined position to form an integrated squib 31.

In the second embodiment as described above, the same effect as that of the squib 1 shown in FIGS. 1 and 2 can be obtained. Moreover, the embolus 72 and the cup 71 are in close contact with each other from the cylindrical portion 71 c of the cup 71 to the opening 71 a, and the sealing property is enhanced by increasing the contact area between the embolus 72 and the cup 71. Can be As a result, it is possible to prevent water, air, etc. from entering (leaking) the inside.

[Gas generator]

Next, a gas generator G using the squib 1 of the present invention will be described.

The gas generator shown in FIG. 10 operates a seat belt pretensioner of an automobile, and includes a squib 1, a holder 52, a gas generating agent 61, and a housing 62.

The holder 52 is a holder for mounting the squib 1, and has a first stepped portion 58 which is a mounting seat of the squib 1 on an inner peripheral surface, and a tapered surface from the top of the flange portion 18 of the squib 1. 21 is a cylindrical body having a second step portion 59 which is in close contact with a part of 21. The inside of the holder 52 is The space provided with the second step portion 59 side from the seat 58 becomes a space 55 for accommodating the flange portion 18 of the squib 1, and the opposite side is the electrode pins 5, 6. There is a space 5 6 for storing

The mounting seat 58 is provided with a seal ring 57. The squib 1 is inserted into the holder 52 from the side of the second step portion 59, and the taper surface 21 of the flange portion 18 is brought into contact with the scenery ring 57 so that the mounting seat 5 is mounted. It is set at 8. The end of the holder 52 on the side where the squib 1 is inserted has a first caulking portion 54 caulked along the shape of the flange portion 18 of the squib 1. Electrode pins 5 and 6 are housed in a space 56 in the holder 52 opposite to the mounting seat 58.

The housing 62 is for accommodating the squib 1 together with the gas generating agent 61, and is a metal-made bottomed cylindrical housing. Gas is discharged from the housing 62 of the gas generator G to the outside of the seat belt pre-tensioner 1 from the housing 62 of the gas generator G. A hole 62a is formed. The gas emission holes 62 a are closed by a thin burst plate 63 made of aluminum or the like.

The side of the holder 52 from which the squib 1 protrudes is inserted into the housing 62. The opening of the housing 62 is closed by the holder 52. A second caulking portion 53 caulked along the opening of the housing 62 is provided on the outer periphery of the holder 152. The gas generator G having the above configuration ignites and burns the igniting charge 3 by the heat generated by the power wire 7 when the electrode pins 5 and 6 of the squib 1 are energized. The flame from the squib 1 ignites and burns the gas generating agent 61 to generate a large amount of gas. Subsequently, a large amount of gas generated in the housing 62 is Breaking the burst plate 6 3 by increasing the internal pressure of the jing 6 2. Then, the gas is released from the gas discharge holes 62 a to the outside of the gas generator G, and is guided to the sheet solelet pretensioner. Then, the seatbelt pretensioner is activated by the high-pressure gas to tighten the seatbelt. If the operation of the squib is secured in a few milliseconds (ms), the gas generator 61 of the gas generator G can be ignited and burned in a few milliseconds (ms). Therefore, it becomes possible to operate the pretensioner within a few milliseconds (ms) from the collision. Thus, when the low-cost squib 1 is used for the gas generator G, the manufacturing cost of the gas generator G itself is also reduced. Can be reduced.

The squib of the present invention can also be applied to a gas generator for inflating and deploying an airbag due to an automobile collision. This gas generator is available for the driver's seat, the passenger seat or for a side collision. The gas generated by burning the gas generating agent inflates and deploys the airbag. The squib is mounted in the gas generator housing. A gas generating agent, a filter, and the like are arranged in the housing. The gas generated by the squib is combusted through the transfer agent or directly by the squib to generate a large amount of gas for inflating and deploying the airbag.

〔Example〕

An experiment was performed to confirm that the squib of the present invention can stably ignite the igniting charge 3 by applying a current of “current value (A) to the electric bridge wire (A) X several milliseconds (ms)”.

A powder or granule containing zirconium as an igniting agent is used, and the space volume of the cup (mm ³ ), the amount of the igniting agent (mg), the diameter of the bridge wire φ (μ πι), Select the length (mm) of the bridge wire as appropriate, and assemble a squib with a loading density of ignition charge 3 of 2 mg / mm ³ or more and 4 mg / mm ³ or less. I prepared it.

Specifically, the space volume in Cup 2 was set to 120 mm ³ , and the loading amount of Ignition Charge ³ was set to 240 mg in order to set the charge density of the ignition charge to 2 mgZmm ³ . To load density of ignition powder 3 and 4 m gZmm ^3, the space volume 30 mm ³ in the cup 2, and the loading of the ignition agent 3 and 1 2 Omg. To the loading density of the ignition powder 3 and SmgZmm ^3, the space volume 3 0 mm ³ in the cup 2, and the loading amount of ignition powder 3 and 9 Omg.

The squib was then energized in a 10 cc container. The time change of the 內 pressure of the container was measured. From these measurement results, it was confirmed that each squib fired within a few milliseconds (ms). Industrial applicability

The squib of the present invention stably ignites the ignition powder without covering the electric wire with an ignition ball containing a harmful substance, and provides a gas generator for protecting and concealing a shellfish such as a seat belt pretensioner pair bag. Operation is guaranteed, reducing costs and making it an ideal eco-friendly squib

Claims

The scope of the claims

1. A squib used for a gas generator that operates an occupant device such as an automobile seat belt pretensioner wear bag,

Cup (2) and

An ignition charge (3) charged in the cup (2);

An embolus (4) for closing the opening of the cup (2);

It is connected between the two electrode pins (5, 6) inserted in the embolus (4) and the two electrode pins (5, 6) in the cup (2), and is ignited by conduction. To the Denbachi Line (7)

The electric bridge line (7) is a squib embedded in the pyrotechnic charge (3).

2. The squib according to claim 1, wherein said electric bridge wire (7) and said igniting agent are sealed in said cup (2) in a state in which a predetermined contact pressure acts on each other.

3. The loading density of the igniting agent (3) in the cup (2) is 2 mgZmm ³ or more and 4 mgZmm ³ or less so that the bridge and the igniting agent are sealed with a predetermined contact pressure acting on each other. The squib according to claim 2, wherein the squib is adjusted to a range of:

4. The method according to claim 1, wherein the igniting charge (3) has a component ignited by the heat generated by the electric bridge wire (7) and is in the form of powder or granules. Squibb.

5. The squib according to claim 1, wherein the igniter (3) has zirconium as a component.

6. A squib used for a gas generator that operates an occupant protection device such as an automobile seat velvet pretensioner or an airbag, comprising a cup (2); An ignition charge (3) charged in the cup (2);

An embolus (4) for closing the opening of the cup (2);

It is connected between the two electrode pins (5, 6) inserted in the embolus (4) and the two electrode pins (5, 6) in the cup (2), and is ignited by conduction. And the Denbashi Line (7),

The two electrode pins (5, 6) are inserted into the embolus (4) so as to form a protruding part (23) projecting from one end of the embolus (4) on the cup side, and

The electric wire (7) is connected between the projecting portions (23) of the electrode pins (5, 6),

The wire (7) and the protrusion (23) are embedded in the ignition charge (3),

A squib in which the electric bridge line (7) and the igniting agent (3) are sealed in the cup (2) under a predetermined contact pressure with each other.

7. At the tip of the protruding portion 23 of each electrode pin (5, 6), a predetermined constant gap h is provided along the axis of each electrode pin (5, 6), and they are arranged on substantially the same plane. The planar welding surfaces (24) arranged are each provided continuously,

7. The squib according to claim 6, wherein both ends of said electric wire (7) are connected to said welding surfaces (24), respectively.

8. The tip (24a) of the projection (23) of each of the electrode pins (5, 6) is folded back so as to cover the connection (25) of the electric bridge line (7). A squib according to scope 6 or 7.

9. The electric bridge wires (7) are respectively connected to the protrusions (23) in a relaxed state where no tension acts between the protrusions (23) of the electrode pins (5, 6). Claim 6 or later, which is sealed in the cup (2). Is the squib described in paragraph 7.

1 0. The as predetermined contact pressure with each other between the bridge wire and the ignition agent is sealed in the state that to act, cup (2) ignition agent in the (3) loading density 2MgZmm ³ or more MgZmm ³ of The squib according to claim 6 or 7, wherein the squib is adjusted to the following range.

1 1. The igniting agent (3) according to claim 6 or 7, wherein the igniting agent (3) has a component that is ignited by the heat generated by the electric wire (7) and is in the form of powder or granules. Type.

1 2. The igniting agent (3) has zirconium as a component.

1 3. A method for manufacturing a squeeze used for a gas generator that operates an occupant protection device such as an automobile seat belt pretensioner or an airbag,

A process of loading resin between the electrode pins (5, 6) and the outer periphery thereof, except for both ends of the two parallel electrode pins (5, 6), to form an embolus (4); ,

Connecting both ends of the electric bridge wire (7) to the projecting portions (23) of the electrode pins (5, 6) projecting from one end of the embolus (4), respectively;

Insert the bridge (7) side of the embolus (4) into the cup, and place the bridge (7) and the protrusion (23) in the igniting agent (3) loaded in the cup (2). The embedding process,

The plug (4) and the cup (2) are fitted so that the wire (7) and the igniting agent (3) are sealed in the cup under a predetermined contact pressure with each other. And a method for manufacturing a squib.

1 4. The electric bridge line (7) and the igniting charge (3) are the igniting charge (3) More adjusting the loading density ZmgZmm ³ or more 4MgZmm ³ or less, the force Tsu squib method according to the first 3 wherein the claims are confined in the flop with a predetermined contact pressure.

15. The method for producing a squib according to claim 13, wherein the squib has a component ignited by the heat generated by the electric bridge wire (7) and uses a powdery or granular igniting agent (3).