JPH0659168U - Acceleration sensor for actuating device of passenger protection device - Google Patents

Abstract

(57) [Abstract] [Purpose] It is possible to easily and accurately position the components of the actuator without the need for troublesome assembly work, and to ensure that the ignition and ignition paths are sealed. [Structure] The acceleration sensor main body 42, the detonator 68, and the enhancer 40 are housed in a housing case 38 in a predetermined positional relationship in order to accurately perform each operation, before being assembled into the central first chamber 34 of the inflator 14. The acceleration sensor 36 is unitized. During rapid deceleration of the vehicle, the collision action causes the collision pin 50 of the acceleration sensor body 42 to move toward the detonator 68 and collide. As a result, the detonator 68 is ignited, the enhancer 40 is ignited, the sealing material 74 that normally closes the communication hole 70 is broken and the communication hole 70 is opened, and the enhancer 40 is ignited through the communication hole 70. Sparks are transferred to the gas generating substance 72 in the second chamber 76 in the middle. When fired, the gas generating substance 72 burns to generate gas, and the generated gas is the bag body 12 of the airbag device 10.
Inflate.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an acceleration sensor for an operating device of an occupant protection device such as an airbag device.

[0002]

[Prior art]

 BACKGROUND ART As a device that protects an occupant in the event of a vehicle collision, an airbag device in which a bag body bulges toward the occupant side is known.

The bag body is inflated by an inflator as an actuating device. For example, in an airbag device for a driver seat mounted on a steering wheel, an inflator includes a gas generating substance annularly arranged around a rotation axis of the steering wheel, and the rotation shaft of the steering wheel is included in the ring. An accelerometer, a detonator, and an enhancer, which are sequentially arranged on the line from the non-occupant side to the occupant side, are provided, and they are housed in a cylindrical housing.

The acceleration sensor moves the collision pin toward the detonator due to the acceleration action accompanying the rapid deceleration of the vehicle. When the collision pin hits the detonator, the detonator fires. The ignition of the detonator ignites the enhancer (explosive powder), and the ignition of the enhancer transfers the spark to the gas generating substance. The gas generating substance burns to generate gas, and the generated gas is supplied into the bag body to swell the bag body.

[0005]

[Problems to be solved by the device]

 By the way, in the conventional inflator, the gas generating substance, the acceleration sensor, the detonator, and the enhancer are individually assembled in the housing.

In order to cause the collision pin of the acceleration sensor to accurately collide with the detonator, to accurately ignite the enhancer by the ignition of the detonator, and to properly transmit the sparks due to the ignition of the enhancer to the gas generating substance, In addition to requiring a highly accurate positional relationship between these parts, it is necessary to take every possible measure to seal the ignition and ignition paths in order to improve the reliability of ignition and ignition.

Therefore, the work of assembling those parts in the housing is troublesome and time-consuming.

In view of the above circumstances, the present invention makes it possible to easily and highly accurately position component parts of an actuating device without requiring troublesome assembling work, and to ensure a perfect seal for ignition and ignition paths. An object of the present invention is to provide an acceleration sensor for an operating device of an occupant protection device, which can be expected.

[0009]

[Means for Solving the Problems]

 In order to solve the above problems, the present invention relates to an acceleration sensor that is used by incorporating it into an operating device that operates an occupant protection device by a gas generated from a gas generating substance that combusts to generate gas when fired. An acceleration sensor body that moves a collision member due to an acceleration action caused by sudden deceleration, a detonator that is ignited by the collision of the movement of the collision member, an enhancer that is ignited by the ignition of the detonator, and the detonator together with the acceleration sensor body. And the enhancer are housed in a predetermined working positional relationship, and a storage case is formed in which a communication hole is formed to allow the enhancer to communicate with the outside and to transmit a flame to a gas generating substance. Normally, the communication hole is closed, and at the time of ignition of the enhancer, a closing member that is broken by the ignition and opens the communication hole is provided. A shall be proposed an acceleration sensor for actuating device for passenger protection device according to claim.

[0010]

[Action]

 According to the acceleration sensor for an actuating device of an occupant protection system according to the present invention, when the vehicle suddenly decelerates, the collision member of the acceleration sensor moves toward the detonator and collides due to the acceleration action accompanying the vehicle sudden deceleration. This causes the detonator to ignite, which in turn ignites the enhancer and when the enhancer ignites, the closing member breaks, the communication hole is opened, and the spark from the enhancer ignites through the communication hole. Is transmitted to the gas generating substance. When fired, the gas generating substance burns to generate gas, and the generated gas actuates the occupant protection device such as bulging the bag body of the air bag device.

Since the detonator and the enhancer are stored together with the acceleration sensor main body in the storage case in a predetermined operating positional relationship, the detonator, the enhancer and the acceleration are not stored when the stored storage case is assembled into the operating device. In order to obtain a predetermined working positional relationship between the sensors, their positioning becomes unnecessary.

Since the enhancer is housed in the storage case and the communication hole is normally closed by the closing member, the collision member ignites the detonator, and the detonator ignites the enhancer. The seal of the ignition path is perfect, and the reliability of ignition of the detonator and ignition of the enhancer is improved.

As described above, with respect to the detonator, the enhancer, and the acceleration sensor main body, their positions can be easily obtained with high accuracy, and the ignition and ignition paths can be completely sealed, which requires troublesome assembly work. Will be achieved without.

[0014]

【Example】

 An acceleration sensor for an actuator of an occupant protection system according to a first embodiment of the present invention will be described with reference to FIGS.

FIG. 2 shows an airbag device 10 for a driver's seat, which constitutes an occupant protection device.

The airbag device 10 includes a bag body 12, an inflator 14 that constitutes an operating device, and a pad 16, and is attached to a base plate 22 that is fixed to a hub 20 of a steering wheel 18.

The bag body 12 is provided with an opening and is arranged in a state of being folded toward the occupant side (arrow A) of the base plate 22, and the opening peripheral edge portion of the bag body 12 is attached to the base plate 22 by the attachment ring 24. Fixed.

The inflator 14 includes a cylindrical housing 26 having a rotation axis of the steering wheel 18 as a cylinder center line. As shown in FIG. 1, the housing 26 is composed of an occupant-side housing body 28 and a lid 30 on the side opposite to the occupant (the side opposite to the arrow A), and the housing body 28 and the lid 30 are both It has a bottom and a flange 32, and is joined between the flanges 32. The flange 32 is for attaching the inflator 14 to the base plate 22. The housing main body 28 of the housing 26 penetrates the base plate 22 and penetrates into the bag body 12 through the opening of the bag body 12.

The housing body 28 is provided with two large and small cylindrical partition walls 86 and 88 having the same cylindrical center line as the housing 26, and the inside of the housing 26 is divided into three chambers.

An acceleration sensor 36 is attached to the first chamber 34 formed in the center. The acceleration sensor 36 includes a storage case 38, and the storage case 38 has a bottomed cylindrical shape corresponding to the indoor shape of the first chamber 34. In the storage case 38, an enhancer (explosive powder) 40 is stored on the passenger side (bottom side of the storage case 38) and an acceleration sensor main body 42 is stored on the anti-passenger side (open side of the storage case 38). .

The enhancer 40 is packed and provided in a fragile cylindrical filling can 44, which facilitates normal handling and facilitates breakage thereof as described later.

The acceleration sensor main body 42 includes a ball 46, a drive shaft 48, and a collision pin 50 that constitutes a collision member, and these are supported in a bottomed cylindrical supporting block 52 having a bottom wall on the occupant side. Be accommodated. The open end of the support block 52 is narrowed and closed by the closing lid 51.

At the time of sudden deceleration of the vehicle, the ball 46 inertially moves toward the occupant side (front of the vehicle) due to the acceleration action, and pushes one end of the drive shaft 48 against the biasing force of the bias spring 54. The drive shaft 48 rotates about a support shaft 56 at the other end of the drive shaft 48, and the trigger portion 58 provided on the support shaft 56 and the locking flange 60 of the collision pin 50 are released from each other, and the collision spring 62 is released. The collision pin 50 can move toward the occupant based on the urging force of. It should be noted that the ball 46, the drive shaft 48, and the collision pin 50 may be provided in a plurality of sets instead of one set, and FIG. 2 shows that two sets are provided (however, in FIG. 2, One of the two sets shows only the collision pin 50).

A movement path 64 for the collision pin 50 is formed in the wall thickness of the bottom wall 53 facing the enhancer 40 of the support block 52, and the movement path 64 communicates with the outer surface of the bottom wall 53. A recess 66 is formed, and a detonator 68 is fitted in the recess 66. The outer surface of the detonator 68 is flush with the outer surface of the bottom wall 53, and the end surface of the filling can 44 of the enhancer 40 abuts on the outer surface of the detonator 68 (the outer surface of the bottom wall 53). The number of the detonators 68 is the same as the number of sets of the balls 46, the drive shafts 48, the collision pins 50, or the number of the collision pins 50.

The collision pin 50 can move along the moving path 64 and collide with the detonator 68, and the detonator 68 is ignited by this collision, and the ignition of the detonator 68 causes the filling can 44 to break due to its fragility. The enhancer 40 in 44 is ignited.

Corresponding to the enhancer 40, the storage case 38 is formed with a communication hole 70 which is a long hole extending from the peripheral wall to the bottom wall. The communication holes 70 are arranged at predetermined intervals along the circumferential direction. A plurality of them are formed.

The enhancer 40 and the outside of the storage case 38 are communicated with each other through the communication hole 70, and the spark generated by the ignition of the enhancer 40 can be transmitted to the gas generating substance 72 described later through the communication hole 70. As shown in FIG. 3, the communication hole 70 is filled with a sealing material 74 that constitutes a closing member, and the sealing material 74 normally closes the communication hole 70, but the enhancer 40 is not attached. It breaks due to heat or pressure to open the communication hole.

The open end of the storage case 38 is bent inward to lock the end of the acceleration sensor main body 42 on the side opposite to the occupant, and between the bottom of the storage case 38, the enhancer 40, the detonator 68, and the acceleration speed. The sensor body 42 is clamped.

The acceleration sensor main body 42, the detonator 68, and the enhancer 40 are housed in the housing case 38 in a predetermined positional relationship to properly perform the above-described operations before being assembled into the inflator 14. Unitized as 36. After that, the unitized acceleration sensor 36 is incorporated into the inflator 14.

When the acceleration sensor 36 is inserted into the first chamber 34 and the housing body 28 and the lid body 30 are joined together, the acceleration sensor 36 is sandwiched between both bottom walls of the housing body 28 and the lid body 30.

Next, as shown in FIG. 1, the gas generating substance 72 is contained in the second chamber 76 located in the middle. The gas generating substance 72 is supplied by being filled in an annular brittle filling can 78 corresponding to the inner shape of the second chamber 76, which facilitates normal handling, and as described later. Fracture is facilitated.

In the outer third chamber 80, the coolant 82 is circumferentially arranged on the side opposite the occupant, and the filter 84 is circumferentially arranged on the side occupant.

On the partition wall 86 between the first chamber 34 and the second chamber 76, a fire transfer hole 90 is opened on the occupant side so as to face the communication hole 70 of the storage case 38. The partition wall 88 between the second chamber 76 and the third chamber 80 is provided with a passage hole 92 on the side opposite to the occupant, and the peripheral wall of the housing main body 28 faces the filter 84 on the side of the occupant. A gas hole 94 is opened.

Sparks from the ignition of the enhancer 40 reach the filling can 78 of the gas generating substance 72 from the communication hole 70 through the fire transfer hole 90. This fragility causes the fill can 78 to rupture and the sparks are transferred to the gas generant 72. The gas generating substance 72 burns to generate gas, and the generated gas enters the third chamber 80 through the passage hole 90, is cooled by the coolant 82, is purified by the filter 84, and is discharged from the gas hole 94. It is supplied into the bag body 12. As a result, the bag body 12 is bulged toward the occupant side.

As shown in FIG. 1, the pad 16 is formed in a bowl shape, and is fixed between the pad 16 and the base plate 22 so as to face down from the occupant side. A thin portion 17 is formed on the bottom wall of the pad 16 facing the occupant, and when the bag 12 is inflated, the thin portion 17 is broken and the pad 16 can be deployed in a double-opened manner.

Next, the operation of the above embodiment will be described. During the rapid deceleration of the vehicle, the collision pin 50 of the acceleration sensor main body 42 moves toward the detonator 68 and collides due to the acceleration effect accompanying the rapid deceleration of the vehicle. As a result, the detonator 68 is ignited, and the enhancer 40 is ignited by the ignition, and when the enhancer 40 is ignited, the seal material 74 is broken, the communication hole 70 is opened, and the enhancer 40 is opened. Sparks from the ignition of 40 are transmitted to the gas generating substance 72. When transmitted, the gas generating substance 72 burns to generate gas, and the generated gas causes the bag body 12 of the air bag device 10 to swell.

The detonator 68 and the enhancer 40 are housed together with the acceleration sensor main body 42 in the housing case 38 in relation to a predetermined operating position. Therefore, when the accelerometer 36 already housed is assembled into the inflator 14, the detonator The positioning of the enhancer and the acceleration sensor is not necessary to obtain a predetermined working positional relationship between them.

Further, since the enhancer 40 is housed in the housing case 38 and the communication hole 70 is normally closed by the sealing material 74, the collision pin 50 ignites the detonator 68 and the detonator 68. The ignition for igniting the enhancer 40 and the seal of the ignition path are perfect for the outside of the storage case 38, and the reliability of ignition of the detonator 68 and ignition of the enhancer 40 is improved.

Therefore, with respect to the detonator 68, the enhancer 40, and the acceleration sensor main body 42, their positioning can be easily obtained with high accuracy, and the ignition and ignition paths can be perfectly sealed. Achieved without cost.

Of course, it is necessary to obtain a predetermined positional relationship between the enhancer 40 and the gas generating substance 72 to ensure the seal of the transmission path, but the capacities of the detonator 68 and the enhancer 40 are different from each other. Since it is smaller than the volume of the substance 72 (especially the detonator 68 is small), a higher positioning accuracy can be obtained between the detonator 68, the enhancer 40 and the acceleration sensor main body 42 than between the enhancer 40 and the gas generating substance 72. In addition, it is necessary to complete the sealing of the ignition and ignition paths. Therefore, by accommodating the detonator 68, the enhancer 40, and the acceleration sensor main body 42 in the storage case 38, they can be positioned with high accuracy without complicated assembly work, and the ignition and ignition paths can be obtained. Being able to complete the seal is extremely effective.

In the first embodiment, the closing member is composed of the sealing material 74, and the sealing material 74 is filled in the communication hole 70 of the long hole. However, for example, in the second embodiment shown in FIG. Like the acceleration sensor 100, a plurality of circular communication holes 102 are formed on the peripheral wall of the storage case 106 corresponding to the enhancer 40 at predetermined intervals along the circumferential direction. A seal tape 104 that is broken by the heat or pressure of the enhancer 40 may be wrapped around the shape, the number and shape of the communication holes, and the closing member are not limited to those in the above-mentioned embodiments. The seal tape 104 can be an aluminum foil tape or the like, and the seal material 74 can be a rubber-based corkong material or the like.

The present invention is not limited to the above embodiment, and various modifications can be made. For example, in the above embodiment, the driver's airbag device was described as the occupant protection device, but the invention of the present application is not limited to other airbag devices for passenger seats or side collisions arranged in the door. The present invention can be applied to various occupant protection devices such as the airbag device described above, or a preloader used for urgently tightening the seat belt to remove the slack remaining on the seat belt and accelerate the restraint by the seat belt.

Further, the structure of the acceleration sensor and the like are not limited to those in the above embodiments, and it is sufficient that the collision member such as the collision pin can be moved toward the detonator by the acceleration action.

[0044]

[Effect of device]

 According to the acceleration sensor for the actuator of the occupant protection device according to the present invention, the detonator, the enhancer, and the acceleration sensor main body can be easily and highly accurately configured without complicated assembly work. The positioning of the ignition can be realized and the ignition and ignition paths can be completely sealed.

[Brief description of drawings]

FIG. 1 is an enlarged view of the inflator shown in FIG.

FIG. 2 is a cross-sectional view of the airbag device including the inflator to which the acceleration sensor according to the first embodiment of the present invention is applied, taken along the rotation axis of the steering wheel.

FIG. 3 is a perspective view of an acceleration sensor according to the first embodiment.

FIG. 4 is a perspective view of an acceleration sensor according to a second embodiment.

[Explanation of symbols]

 10 occupant protection device 14 inflator (actuator) 36 acceleration sensor 38 storage case 40 enhancer 42 acceleration sensor body 50 collision pin (collision member) 68 detonator 70 communication hole 72 gas generating substance 74 sealing material (closing member)

Claims (1)

[Scope of utility model registration request] 1. An acceleration sensor, which is used by being incorporated in an actuation device for actuating an occupant protection device by gas generated from a gas generating substance that burns to generate gas when it is transferred, by an acceleration action due to sudden vehicle deceleration. An acceleration sensor body that moves a collision member, a detonator that is ignited by a collision caused by the movement of the collision member, an enhancer that is ignited by the ignition of the detonator, and a predetermined operating positional relationship between the detonator and the enhancer together with the acceleration sensor body. And a storage case formed with a communication hole that allows the enhancer to communicate with the outside and to transfer the flame to the gas generating substance.
An operation of the occupant protection device, characterized in that the occupant protection device is provided with a closing member that is normally provided in the storage case and that closes the communication hole and that is broken when the enhancer is ignited to open the communication hole. Accelerometer for equipment.