JPH0592744U - Acceleration sensor - Google Patents

Abstract

(57) [Abstract] [Purpose] The urging force of the activating biasing means that moves and urges the activating member to the activating position in the process of rotating the activating member to allow the activating member to move to the activating position. It suppresses reaching as a counter-rotating direction force of. At the engagement position of the trigger member 56 with the engagement flange 52, the urging force of the ignition spring 54 causes the trigger member 56 to move.
The trigger member 56 extends in the direction orthogonal to the moving direction of the ignition pin 38, and the engaging collar 5 of the trigger member 56 extends.
2 from the engagement position with the engagement position 2 to the engagement disengagement position along the blocking portion 58 on the housing 40 side, and the trigger member 56.
The movement of the ignition pin in the biasing direction is blocked. A process in which the lever 46 rotates from the first position to the second position when the vehicle is rapidly decelerated, and the rotation protrusion 62 that rotates integrally with the lever 46 moves the trigger member 56 to the disengagement position with the engagement collar 52. Therefore, the biasing force of the ignition spring 54 does not reach the counter-rotating direction force of the lever 46.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an acceleration sensor that includes an inertial body that inertially moves due to an acceleration action, and that activates an occupant protection device when the vehicle rapidly decelerates due to inertial movement of the inertial body.

[0002]

[Prior Art]

 BACKGROUND ART An airbag device is known as a vehicle occupant protection device.

The airbag device is designed to protect the occupant by bulging the bag when the vehicle suddenly decelerates, and an acceleration sensor is used to activate the airbag device when the vehicle suddenly decelerates.

In the acceleration sensor, conventionally, as shown in FIG. 3 (indicated by an arrow FR in front of the vehicle), the ball 80 is an inertial body, and when the ball 80 receives acceleration during sudden deceleration of the vehicle, the ball 80 moves toward the front of the vehicle. Inertial movement is possible.

A lever 82 is arranged in a direction orthogonal to the inertial movement direction of the ball 80, and one end of the lever 82 extends to the front surface of the ball 80 in the inertial movement direction. When one end of the lever 82 is pressed by the inertial movement of the ball 80, the shaft 83, which fixes the intermediate part of the lever 82 and forms a rotating body together with the lever 82, rotates the support shafts 84 at both ends of the shaft. Is rotated together with the lever 82.

On the other hand, an ignition pin 86 as an activation member is provided in parallel with the inertial movement direction of the ball 80, and the ignition pin 86 is constantly moved from the non-activation position to the activation position for igniting the detonator by the ignition spring 94. Being energized. An engaging collar 88 is formed at an intermediate portion in the moving direction of the ignition pin 94, and a part of the peripheral surface of the shaft body 83 is cut out to correspond to the engaging collar 88, and a trigger portion is formed. 90 is formed, and the engagement collar 88 and the trigger portion 90 can be disengaged with the rotation of the shaft 83.

Normally, the engagement flange 88 and the trigger portion 90 are engaged with each other to prevent the ignition pin 86 from moving to the starting position. At this time, the biasing force of the ignition spring 94 causes the trigger portion 9 to move. It exerts a pressing force on 0.

At the time of sudden deceleration of the vehicle, the ball 80 inertially moves, and when the lever 82 is rotated against the rotational biasing force of the bias spring 92 that presses the other end of the lever 82, it is triggered together with the shaft body 83. The portion 90 is integrally rotated, and the engagement between the engaging collar 88 and the trigger portion 90 is released. As a result, the ignition pin 86 is allowed to move to the starting position, and based on the urging force of the ignition spring 94, the ignition pin 86 moves toward and contacts the detonator, and the detonator is ignited. By the ignition of the detonator, the gas generating substance is burned to generate gas, and the generated gas is supplied into the bag body and the bag body is expanded.

[0009]

[Problems to be solved by the device]

 By the way, in the above-described conventional acceleration sensor, in the process in which the shaft body 83 rotates to release the engagement between the engagement flange 88 and the trigger portion 90, the pressing force of the ignition spring 94 exerted on the trigger portion 90 is applied. Based on this, the distance between the engagement point between the engagement collar 88 and the trigger portion 90 (the contact point between the peripheral edge of the engagement collar 88 and the notch end of the trigger portion 90) on the shaft body 83, and the support shaft 84. A rotational moment with L as the length of the arm is applied in a direction that hinders the inertial movement of the ball 80. In particular, the urging force of the ignition spring 94 is considerably large because it is necessary to ignite the detonator.

In view of the above facts, the present invention provides a starter urging means for moving and urging the starter member to the start position in the process of rotating the rotating body in allowing the starter member to move to the start position. It is an object of the present invention to provide an acceleration sensor in which the biasing force is suppressed from acting as a counter-rotating direction force of a rotating body.

[0011]

[Means for Solving the Problems]

 In order to solve the above problems, the present invention provides an acceleration sensor for activating an occupant protection device, which includes an inertial body that inertially moves due to an acceleration action, and the inertial movement of the inertial body causes the first position when the vehicle suddenly decelerates. To a second position, a starting member movable from a non-starting position to a starting position for starting the occupant protection device, and a starting biasing means for moving and biasing the starting member to the starting position. An engaging portion provided on the starting member so as to be integrally movable, and a member for releasing the engagement of the engaging portion from an engaging position at which the engaging portion engages in a direction orthogonal to the moving direction of the starting member. A trigger member that moves to the engagement release position to prevent the activation member from moving to the activation position at the engagement position and allows the activation member to move to the activation position at the engagement disengagement position; and this trigger member moves the activation member. Engagement in the direction orthogonal to the direction Guide means for guiding the movement from the position to the disengagement position, and a pivot member provided integrally rotatably on the rotating body to rotate the rotating body from the first position to the second position to move the trigger member from the engaging position. The present invention proposes an acceleration sensor including a moving unit that moves to an engagement release position.

[0012]

[Action]

 According to the acceleration sensor of the present invention, normally, the rotating body is in the first position, and in the first position, the trigger member is in the engaging position with the engaging portion and the activating member is in the non-activating position. Retained.

At the time of sudden deceleration of the vehicle, the inertial body inertially moves, and the rotating body is rotated to the second position. The moving part is integrally rotated with the rotating body, and accordingly, the trigger member is guided and moved by the guiding means to the position for releasing the engagement with the engaging part. At the position where the trigger member is disengaged from the engagement portion, the activation member is allowed to move to the activation position, and the occupant protection device can be activated.

Here, at the engagement position of the trigger member with the engagement portion, the urging force of the activation urging means acts on the trigger member, but the trigger member moves from the engagement position with the engagement portion. The moving direction to the disengagement position is perpendicular to the moving direction of the starting member by the guiding means, the movement of the trigger member in the biasing direction of the starting member is blocked, and the rotating body moves from the first position to the first position. It is suppressed that the biasing force of the starting biasing means acts as a counter-rotating direction force of the rotating body in the process of rotating to the 2 position and the moving part moving the trigger member to the disengagement position with the engaging part. Be done.

[0015]

【Example】

 An acceleration sensor according to an embodiment of the present invention will be described with reference to FIGS.

In FIG. 2 (arrow FR indicates the front of the vehicle), an airbag device 10 is shown. The airbag device 10 includes an inflator 12, a cover 14, and an airbag bag body (hereinafter, simply referred to as a bag body 16), and is attached to a base plate 22 supported by a hub 20 of a steering wheel 18.

The inflator 12 has a cylindrical shape whose outer peripheral surface is formed around the rotation axis of the steering wheel 18, and a substantially half of the inflator 12 in the rotation axis direction penetrates the base plate 22 toward the occupant side and projects. It is fixed to the base plate 22 by a mounting flange 24.

The bag body 16 is arranged in a folded state on the occupant side of the base plate 22, and the peripheral portion of the bag body opening is attached so that the occupant side protruding portion of the inflator 12 enters the bag body opening. It is fixed to the base plate 22 by a ring 28.

The cover 14 is formed in a bowl shape, and is fixed to the base plate 22 so that the bag body 16 is housed between the cover 14 and the base plate 22 so as to face down from the occupant side. A thin portion 29 is formed on the bottom wall of the cover 14 facing the occupant, and when the bag body 16 is inflated, the thin portion 29 is broken and the cover 14 can be deployed in a double door structure. There is.

Further, the inflator 12 houses the enhancer 30, the detonator 32, the gas generating substance 34, and the acceleration sensor 36, and when the vehicle decelerates rapidly, the ignition pin 38, which constitutes a starting member on the acceleration sensor 36 side, is connected to the detonator 32. Upon collision, the detonator 32 is ignited, the gas generating substance 34 is ignited based on the ignition to generate gas, and the gas is supplied into the bag body 16 through the gas hole 39.

Here, the acceleration sensor 36 will be described in detail. In the acceleration sensor 36, as shown in FIG. 1, a ball 42 forming an inertial body is provided inside a housing 40. The ball 42 is housed in the cylinder 44, and when acceleration acts on the ball 42, the ball 42 can inertially move in the cylinder 42 forward of the vehicle.

A lever 46 that constitutes a rotating body and the ignition pin 38 are provided in the housing 40. The lever 46 is arranged in a direction orthogonal to the moving direction of the inertial body 42, and one end (the left end in FIG. 1) of the lever 46 is in front of the inertial moving direction (the surface on the front side of the vehicle) of the inertial body 42. It is extended. A support shaft 48 is formed at an intermediate portion of the lever 46, and the support shaft 48 is attached to the housing 40 by making the axial direction orthogonal to both the inertial movement direction of the ball 42 and the extension direction of the lever 46. When the ball 42 inertially moves forward of the vehicle and presses one end of the lever 46, the lever 46 pivots about the support shaft 48 in the counterclockwise direction (arrow A) in FIG. Is rotated to.

On the other hand, the ignition pin 38 is arranged such that its longitudinal direction is parallel to the moving direction of the ball 42, and the vehicle rear end of the ignition pin 38 is located along the guide movement path 50 formed through the housing 40. 40, a starting position (shown by a chain line in FIG. 1) where the detonator 34 is ignited by contacting the detonator 34 to start the air bag device 10, and the vehicle rear end of the ignition pin 38 is located in the housing 50. It can be moved to and from the non-start position (shown by the solid line in Fig. 1). An engaging collar 52 that constitutes an engaging portion is provided at an intermediate portion of the ignition pin 38, and an ignition spring 54 that constitutes a starting biasing means is interposed between the engaging collar 52 and the housing 40. Has been done. According to the coil spring 54, the ignition pin 38 is constantly urged to move to the starting position and applies the ignition force to the detonator 34 at the starting position.

A trigger member 56 is provided corresponding to the engaging collar 52. The trigger member 56 is urged in the ignition pin urging direction (to the starting position of the ignition pin 38) by the blocking portion 58 which constitutes a guide means projectingly formed in the housing 40 in a direction orthogonal to the moving direction of the ignition pin 38. Movement of the engaging pin 52 along the blocking portion 58 in the direction orthogonal to the moving direction of the ignition pin 38, and the engaging collar 52. Is guided to and from an engagement releasing position for releasing the engagement with. A trigger spring 60 is interposed between the trigger member 56 and the housing 40. According to the trigger spring 60, the trigger member 56 is urged to move to an engaging position with the engaging collar 52, and is engaged. It has stopped by hitting the small diameter portion 52A of the collar 52.

In the engagement position of the trigger member 56 with the engagement collar 52, the movement of the ignition pin 38 to the activation position is blocked, and at this time, the biasing force of the ignition spring 54 is triggered by the engagement collar 52. A pressing force is exerted on the member 56. At the position where the trigger member 56 is disengaged from the engagement flange 52, the ignition pin 38 is allowed to move to the activation position.

Further, the end of the trigger member 56 on the engagement flange 52 side is formed in a stepped shape, and the rotating projection 62 constituting the moving portion is in contact with and engaged therewith. The engaging projection 62 extends in the radial direction of the support shaft 48 and is provided so as to be integrally rotatable with the lever 46.

When the ball 42 inertially moves and the lever 46 rotates from the first position shown by the solid line in FIG. 1 to the second position shown by the chain line in FIG. 1, the rotation protrusion 62 is rotated. , The trigger member 56 is pressed to counteract the biasing force of the trigger spring 60 and move the trigger member 56 to the disengaged position with the engaging portion 52.

At the other end of the lever 46 (the right end in FIG. 1), a bias spring 64 is provided between the lever 46 and the housing 40, and a pressing force is applied to the lever via the bias member 66. , The lever 46 is constantly biased to rotate to the first position.

Next, the operation of this embodiment will be described. In normal vehicle running, the acceleration acting on the ball 42 is small, the inertial movement of the ball 42 is blocked by the biasing force of the bias spring 64, and the lever 46 does not rotate from the first position to the second position. The trigger member 56 is in the engagement position with the engagement collar 52, and the ignition pin 38 is held in the non-actuated position.

At the time of sudden deceleration of the vehicle, the acceleration is large, the ball 42 inertially moves against the biasing force of the bias spring 64, and the lever 46 is rotated from the first position to the second position. Along with this rotation, the rotation protrusion 62 is rotated, and the trigger member 56 is moved to the release position with the engaging flange 52 along the blocking portion 58. Then, the engagement between the trigger member 56 and the engagement collar 52 is released, and the ignition pin 38 is moved from the non-activated position to the activated position based on the biasing force of the ignition spring 54. As a result, the airbag device 10 can be activated.

Here, at the engagement position of the trigger member 56 with the engagement flange 52, the biasing force of the ignition spring 54 acts on the trigger member 56, but the trigger member 56 moves the ignition spring 54. Since it is guided along the blocking portion 58 from the engaged position to the disengaged position in the direction orthogonal to the direction, the movement of the trigger member 56 in the firing pin urging direction is blocked, and the lever 46 is moved to the first position. From the second position to the second position, the pivot projection 62 moves the trigger member 56 to the disengagement position with the engaging collar 52, and the biasing force of the ignition spring 54 causes the lever 46 to move to the ball 42. It does not act as a rotational force in the direction against the inertial force (clockwise in FIG. 1).

As a result, it is possible to prevent the biasing force of the ignition spring 54 from acting as a counter-rotating direction force of the lever 46 in the process of rotating the lever 46 to allow the ignition pin 38 to move to the starting position. As a result, the smooth rotation of the lever 46 on the support shaft 48 is achieved.

In particular, since the urging force of the ignition spring 54 is considerably large to ignite the detonator 34, the above effect is remarkable.

The present invention is not limited to the above embodiment, but various modifications can be made. For example, in the above embodiment, the occupant protection device is the airbag device 10. However, the occupant protection device is not limited to this. Of course, it can also be used to activate the preloader for a tight fit.

[0035]

[Effect of the device]

 According to the acceleration sensor of the present invention, the urging force of the activation urging means that moves and urges the activation member to the activation position is rotated during the process in which the rotating body rotates to allow the movement of the activation member to the activation position. It is suppressed that the moving body acts as a counter-rotating direction force.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an acceleration sensor according to an embodiment of the present invention, taken along the vehicle longitudinal direction.

FIG. 2 is a cross-sectional view taken along the vehicle front-rear direction of an airbag device to which an acceleration sensor according to an embodiment of the present invention is applied.

FIG. 3 is a sectional view of a conventional acceleration sensor taken along the vehicle front-rear direction.

[Explanation of symbols]

 10 Airbag device (occupant protection device) 42 Ball (inertial body) 36 Acceleration sensor 38 Ignition pin (starting member) 46 Lever (rotating body) 52 Engagement collar (engagement part) 54 Ignition spring (starting biasing means) 56 Trigger member 58 Blocking portion (guide means) 62 Rotating protrusion (moving portion)

Claims (1)

[Scope of utility model registration request] 1. An acceleration sensor for activating an occupant protection device, comprising an inertial body that inertially moves due to an acceleration action, and the inertial movement of the inertial body causes the inertial body to rotate from a first position to a second position during rapid vehicle deceleration. Rotating body, a starting member movable from a non-starting position to a starting position for starting the occupant protection device, a starting biasing means for moving and biasing the starting member to the starting position, and an integral movement to the starting member. Engage by moving the provided engaging part and the engaging position where the engaging part engages in the direction orthogonal to the moving direction of the actuating member to the engaging release position where the engagement with the engaging part is released. A trigger member that prevents the actuating member from moving to the actuating position at the position and allows the actuating member to move to the actuating position at the disengagement position, and the trigger member is engaged in the direction orthogonal to the moving direction of the actuating member. Proposal to move from position to disengagement position A guide unit provided therein, and a moving section provided integrally with the rotating body to move the trigger member from the engaging position to the disengaging position by rotating the rotating body from the first position to the second position. An acceleration sensor comprising: