JPH08113108A - Sensor for occupant protecting device - Google Patents

Abstract

PURPOSE: To provide a sensor for the occupant protecting device capable of easily performing adjustment of the sensor mounting position or the sensitivity of the sensor itself, and judging a vehicle collision state in a short time. CONSTITUTION: A sensor 20 is made up of an electric conductor 22 and a permanent magnet 24 to detect the value of current caused by induced electromotive force generated due to the relative displacement between both the above conductor and the permanent magnet. That is, the sensor 20 is structured not to merely detect load or displacement, but detect the amount of current variations which is changed due to the relative displacement speed (acting speed of load), and based on the detected amount of current variations the sensor makes a judgement of collision. Thus, the sensor mounting position or the sensitivity of the sensor can be easily adjusted, and the vehicle collision state can be judged in a short time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sensor for an occupant protection device which is arranged inside a door panel of a vehicle, for operating an occupant protection device such as an airbag.

[0002]

2. Description of the Related Art For the purpose of protecting an occupant in a vehicle collision (particularly in a side collision), air for a vehicle door that detects a sudden deceleration of the vehicle in a collision and bulges the back toward the occupant. Bag devices have been proposed. Such an airbag device is equipped with a sensor that detects a side collision state (load / displacement applied to the vehicle) of the vehicle, and is attached to an impact beam provided on the vehicle door and arranged to face the door outer panel. What is done is proposed.

A conventional sensor of this type has a pair of thin parallel counter electrodes. The peripheral portions of the pair of thin parallel opposing electrodes are opposed to each other in parallel with an insulator formed in the shape of a thin frame interposed therebetween, and the periphery thereof is covered with a surface coating material. Furthermore, one thin parallel counter electrode of the pair of thin parallel counter electrodes has elasticity and can be flexibly deformed, and the surface coating material on the side of the thin parallel counter electrode is provided with a pressing protrusion. .

When the vehicle is in a side collision state and the door outer panel is deformed toward the interior of the vehicle, the pressing projection is pressed by the door outer panel or the like, and one thin parallel counter electrode is flexibly deformed, and the other thin parallel counter electrode is deformed. It is configured such that the airbag device is actuated by making contact and conducting (the sensor is turned on).

In such a sensor, the operating current for operating the airbag device can be directly controlled (ON / OFF) by the sensor, and the sensor is arranged at the position closest to the door outer panel. The vehicle collision state (that is, the deformation of the door outer panel) can be quickly detected (the time lag is small).
There are various advantages.

However, the conventional sensor having the structure for detecting the load / displacement as described above satisfies the operation requirement of the sensor for detecting the collision state of the vehicle, and, for example, when the door is slightly rubbed or is mischievous. When a load is applied to the door, a complicated work is required to adjust the sensor mounting position and its sensitivity so as not to unnecessarily detect the load and operate the airbag device.

[0007]

SUMMARY OF THE INVENTION In consideration of the above facts, the present invention provides a sensor for an occupant protection device in which the sensor mounting position and its sensitivity can be easily adjusted and the collision state can be determined in a short time. Is the purpose.

[0008]

A sensor for an occupant protection device according to the present invention is a sensor for an occupant protection device for operating an occupant protection device provided in a vehicle, comprising an electric conductor and a magnet, One of the conductor and the magnet is fixedly provided on the inner side of the vehicle and the other is provided on the outer side of the vehicle so as to face the one, and an induced electromotive force is generated by relative movement of the conductor and the magnet. It is characterized in that a current value resulting from the induced electromotive force is detected.

[0009]

In the occupant protection device sensor having the above structure, one of the conductor and the magnet is fixedly provided, for example, on the door inner panel of the vehicle door, and the other is attached to, for example, an impact beam provided on the outside of the vehicle. And is arranged facing one side.

Here, when the vehicle is in a sudden deceleration (collision) state, for example, the impact beam is pushed by the door panel or the like and moved to the inside of the vehicle. Along with this, the other of the conductor and the magnet, which is provided on the outer side of the vehicle, is moved to the inner side of the vehicle and moves relatively to the one. An induced electromotive force is generated by the relative movement of the conductor and the magnet, and the current value resulting from the induced electromotive force is detected. The occupant protection device is activated based on the detected pressure (for example, whether or not a predetermined value is exceeded).

In the occupant protection device sensor, the current value generated by the relative movement of the conductor and the magnet is
It changes according to the relative moving speed of the conductor and the magnet, that is, the acting speed of the load applied to the vehicle. For example, if the door is rubbed slightly or a load is applied to the door due to mischief, the relative moving speed of the conductor and the magnet is slow, and therefore the amount of change in current value is small. On the other hand, in a state where the vehicle is truly in a collision state and the occupant protection device is to be truly actuated, the relative moving speed of the conductor and the magnet is high, and thus the current value change amount is large. That is, in the sensor for passenger protection device, in order to detect the collision based on the current value change amount that changes depending on the relative moving speed of the conductor and the magnet,
It is possible to operate the occupant protection device by determining the collision state in a short time.

As described above, with the sensor for an occupant protection device according to the present invention, the sensor mounting position and its sensitivity can be easily adjusted, and the state of collision can be determined in a short time.

[0013]

1 is a sectional view of a vehicle door 10 to which an occupant protection device sensor 20 according to a first embodiment of the present invention is applied. In addition, an arrow UP that is appropriately shown in the drawing
Indicates the vehicle upward direction, and the arrow IN indicates the vehicle interior direction.

The door 10 is provided with an outer panel 12 and an inner panel 14, and these outer panel 12 is provided.
The inner space 14 is formed by the inner panel 14 and the inner panel 14. An impact beam 18 is arranged in the interior space 16 of the door. The impact beam 18 has an elongated shape and is arranged inside the door 10 along the vehicle front-rear direction. The impact beam 18 is made of high-tensile steel plate or aluminum alloy,
When a high load in the direction of arrow A in FIG. 1 acts on the door 10, the deformation amount of the outer panel 12 and the inner panel 14 is limited. A sensor 20 is arranged between the impact beam 18 and the inner panel 14.

The sensor 20 includes a conductor 22 and a permanent magnet 24.
It has and. The conductor 22 is, for example, a conductive coil, and is fixedly provided on the inner panel 14 of the door 10. On the other hand, the permanent magnet 24 is attached to the impact beam 18 so as to face the conductor 22 on the vehicle outer side of the conductor 22. As a result, when the impact beam 18 is deformed (moved) inward of the vehicle, the permanent magnet 24 is moved inward of the vehicle together with the impact beam 18 and moves relatively close to the conductor 22. An induced electromotive force can be generated by the relative movement of the conductor 22 and the permanent magnet 24, and the current value resulting from this can be detected.

Further, as shown in FIG. 2, the conductor 22 of the sensor 20 has a collision determination circuit 2 through a filter circuit 26.
8, and the collision determination circuit 28 is electrically connected via an ignition circuit 30 to an electric ignition type airbag device (not shown) as an occupant protection device.

Next, the operation of the first embodiment will be described. According to the sensor 20 having the above-described configuration, when the vehicle is in a sudden deceleration (collision) state and the impact beam 18 is deformed (moved) inwardly of the vehicle due to, for example, the deformation of the door outer panel 12, the permanent magnet 24 causes the impact beam 24 to move. It moves to the inside of the vehicle together with 18, and moves relatively close to the conductor 22. An induced electromotive force is generated by the relative movement of the conductor 22 and the permanent magnet 24, and the current value resulting from the induced electromotive force is detected. When the detected current value exceeds, for example, a predetermined value, the collision determination circuit 28 determines that the vehicle has reached a collision state, the ignition circuit 30 is closed, and the airbag device is operated.

Here, in this sensor 20, a conductor 22
And the current value detected by the relative movement (induced electromotive force) of the permanent magnet 24 depends on the relative movement speed of the conductor 22 and the permanent magnet 24 (in other words, the action speed of the load applied to the door 10). Change.

For example, if the door 10 (outer panel 1
2) When the door 10 is slightly rubbed, when the door 10 is loaded with a mischief, or when the vehicle collides at a low speed, the relative moving speed of the conductor 22 and the permanent magnet 24 is slow, and therefore the induced electromotive force is small. Therefore, the amount of change in the current value detected by the sensor 20 is small as shown by lines B and C in FIG. On the other hand, when the vehicle truly reaches a collision state and the airbag device is to be truly actuated, the conductor 22 and the permanent magnet 2 are
The relative movement speed of No. 4 is high, and therefore the induced electromotive force is large. Therefore, as shown by the line A in FIG. That is, in the sensor 20,
Since the amount of change in the current value that changes depending on the relative moving speed of the conductor 22 and the permanent magnet 24 is detected and the collision is determined based on this, the collision state can be determined in a short time and the airbag device can be operated.

Further, since the sensor 20 only needs to have a circuit configuration for detecting a current value exceeding a predetermined value, it is possible to determine the collision state in an extremely short time. Furthermore, in the sensor 20,
By appropriately setting the arrangement positions and the number of arrangements of the conductors 22 and the permanent magnets 24, it is possible to optimally respond to the collision mode of a large number of vehicles (for example, when the opponent is a large vehicle or a small vehicle). Is possible.

As described above, the sensor 2 according to the first embodiment.
At 0, the sensor mounting position and its sensitivity can be easily adjusted, and the vehicle collision state can be determined in a short time.

The collision state is not limited to whether the detected current value exceeds a predetermined value or not. For example, the duration of the current value exceeding the predetermined value (in other words, the amount of generated energy) It may be configured to determine the collision based on the collision. In this case, when a so-called hammer blow-like external force due to mischief or the like is applied, the collision state is not determined, which is more effective.

Further, in the first embodiment, the conductor 22 is fixedly provided on the inner panel 14 of the door 10, and the permanent magnet 24 is attached to the impact beam 18 on the vehicle outer side than the conductor 22. However, the configuration is not limited to this, and the arrangement positions of the two may be interchanged (reversed). Even in this case, the collision can be determined by detecting the current value generated by the relative movement of the permanent magnet 24 and the conductor 22.

Furthermore, in the first embodiment, one of the permanent magnet 24 and the conductor 22 is attached to the impact beam 18 provided on the door 10, but the present invention is not limited to this, and other members may be used. It may be attached.

For example, as in the sensor 40 according to the second embodiment shown in FIG. 4, an inner plate 42 whose lower end is a supporting end is provided in the door 10, and the permanent magnet 24 and the conductor are attached to the inner plate 42. One of the 22 may be attached. Even in this case, when the vehicle reaches a collision state, the inner plate 42 is deformed inwardly of the vehicle, and the conductor 22 and the permanent magnet 24 are relatively moved to detect the current value.

Further, instead of the permanent magnet 24 in each of the above-mentioned embodiments, an electromagnet may be used. In this case, the power supply to the electromagnet is released, for example, when the vehicle is stopped, so that the magnetic powder or the like that is unnecessarily magnetized is removed. This point is advantageous over the permanent magnet 24.

In each of the above embodiments, the conductor 2
Although 2 has been described as a simple conductive coil, the present invention is not limited to this, and a configuration including a high magnetic permeability material such as the sensor 50 according to the third embodiment shown in FIGS. Even if the relative speed is low, it is possible to obtain a high output as a current value.

The sensor 50 comprises a coil portion 52 made of a high magnetic permeability material, a permanent magnet 54, and a moving member 56 made of a high magnetic permeability material. A convex portion 58 is formed at the tip of the moving member 56, and is arranged so as to move toward and away from the tip portion 52A of the coil portion 52. In this sensor 50, when the vehicle reaches a collision state, the moving member 56 is moved so that the convex portion 58 faces the tip portion 52A of the coil portion 52 as shown in FIG. 5B. As a result, the current value can be detected.

In this case, when a simple conductive coil is used, a high output cannot be obtained as a current value when the relative speed is slow as shown by the line B in FIG. 6, but the sensor 50 according to the third embodiment is used. As shown in the following, when the structure is provided with a high magnetic permeability material,
As shown by the line A in FIG. 6, it is possible to obtain a high output as a current value even if the relative speed is slow.

As described in each of the above embodiments, the sensors 20, 40, 50, etc. detect the amount of change in the current value which changes depending on the relative moving speed of the conductor 22 and the permanent magnet 24, and collide based on the detected amount. Since the determination is made, the collision state can be determined in a short time. Further, the sensor mounting position and its sensitivity can be easily adjusted.

By appropriately setting the arrangement position and the number of arrangements, it is possible to optimally cope with different collision modes, and this can be realized at low cost.

In each of the above embodiments, the impact beam 18 and the inner plate 42 provided on the vehicle door 10 are provided.
Although the sensor 20 and the like are attached to the vehicle, the body panel is not limited to this, and may be disposed on the outer periphery of the vehicle and may collide with another vehicle (for example, an outer panel of a back door of a wagon vehicle or the like). Etc.), the present invention can be applied to all.

Further, in each of the above-mentioned embodiments, an airbag device provided on a vehicle door is applied as an occupant protection device,
Although the configuration in which the airbag device is operated by the sensor 20 or the like has been described, the present invention is not limited to this, and the airbag is provided in another occupant protection device, for example, a webbing winding device, and the winding shaft is rapidly wound in the winding direction at the time of a vehicle collision. It may be applied to a vehicle provided with a so-called preload device for rotating the motor to operate them.

[0034]

As described above, the sensor for an occupant protection device according to the present invention has an excellent effect that the sensor mounting position and its sensitivity can be easily adjusted and the state of collision can be judged in a short time. are doing.

[Brief description of drawings]

FIG. 1 is a sectional view of a vehicle door to which a sensor for an occupant protection device according to a first exemplary embodiment of the present invention is applied.

FIG. 2 is a configuration diagram of an electric circuit for operating an occupant protection device to which a sensor for an occupant protection device according to a first exemplary embodiment of the present invention is applied.

FIG. 3 is a diagram showing a change state of a quantity of electricity detected by a sensor for an occupant protection device according to the first exemplary embodiment of the present invention.

FIG. 4 is a sectional view of a vehicle door to which an occupant protection device sensor according to a second exemplary embodiment of the present invention is applied.

FIG. 5 is a configuration diagram of an occupant protection device sensor according to a third embodiment of the present invention.

FIG. 6 is a diagram showing a relationship between a current value detected by a sensor for an occupant protection device and a relative speed according to a third embodiment of the present invention.

[Explanation of symbols]

 20 sensor 22 conductor 24 permanent magnet 40 sensor 50 sensor 52 coil part 54 permanent magnet 56 moving member 58 convex part

Claims (1)

[Claims] 1. An occupant protection device sensor for operating an occupant protection device provided in a vehicle, comprising: a conductor and a magnet, wherein one of the conductor and the magnet is fixed to an inner side of the vehicle. And the other is provided outside the vehicle so as to face the one, and an induced electromotive force is generated by relative movement of the conductor and the magnet to detect a current value caused by the induced electromotive force. Characteristic occupant protection device sensor.