JPH0958401A - Air bag device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect a side collision in relatively wide areas by providing multiple resonance circuits with multiple inductances which are arranged at the relative positions to the deformed and nondeformed parts of a vehicle body at the initial stage of collision and affect resonance conditions, and judging each of the outputs from these resonance circuits. SOLUTION: Oscillation circuits 20A and 20B are provided with inductances LA and LB, respectively, which are arranged at the relative positions to the deformed and nondeformed parts of a vehicle body at the initial stage of collision and affect resonance conditions. Also comparison circuits COMP 1, COMP 2, COMP 3, and COMP 4 judge whether or not the outputs from the oscillation circuits 20A and 20B are larger than specified threshold values VTH1, VTH2, VTH3, and VTH4, respectively. Then the output compared with lower threshold values VTH1 and VTH3 is led to AND2 through AND 1 of AND gate. In addition, the output compared with higher threshold values VTH2 and VTH4 is led to AND2 of AND gate through OR of OR gate. Thus the ignition command signal of the squib PS of an inflator can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag device as an occupant protection device for ensuring passive safety of an occupant, and an airbag device for detecting a full-scale collision in a large vehicle such as a truck or a bus. It is about.

[0002]

2. Description of the Related Art In recent years, airbag devices have been widely used in the automobile industry for the purpose of ensuring passive safety of passengers. In addition to airbag devices for head-on collisions (head-on collisions), recently, right and left vehicle bodies have been used. Side impact airbag devices that protect passengers from side collisions (side impacts) have also been adopted. In such an airbag apparatus for side impact, a sensor such as a touch switch is provided as a collision sensor for detecting a side collision, for example, on a side door beam inside a door.

An example of such a conventional side impact airbag device is the technique disclosed in Japanese Utility Model Laid-Open No. 5-563.

The technology disclosed in Japanese Utility Model Publication No. 5-563 is as follows.
A sensor for detecting a side collision is arranged at a position separated from the left and right door panels of the automobile by a predetermined distance, and the sensor is pressed by a body panel which is deformed at the time of a collision so as to conduct electricity. That is, in this technique, the sensor is composed of a fixed contact and a moving contact, and the moving contact is fixed to the door panel so as to approach the fixed contact and make contact with the door when the door is deformed.

[0005]

However, since the conventional air bag device is constructed as described above, in order to detect the side surface crash of the vehicle body in the case of a side collision, the airbag device is installed. There is a possibility that the number of sensors increases, the cost increases, and the circuit configuration becomes complicated. Especially,
Damage to the car body due to side impacts covers a wide range of side surfaces, and it is estimated that the reliability of local detection is not good.

Therefore, the first object of the present invention is to detect changes in a wide range of surfaces, and it is a second object to detect changes in a wide range of surfaces and improve its reliability. It is an object of the present invention to provide an airbag device which is a subject of the above.

[0007]

According to a first aspect of the present invention, there is provided an air bag device in which an inflator for inflating and deploying an air bag disposed in a vehicle is relatively opposed to a portion of a vehicle body that is displaced at the initial stage of collision and a portion that is difficult to be displaced. A plurality of resonance circuits having a plurality of inductances that influence the resonance condition arranged at a position, and determine a plurality of outputs from each of the plurality of resonance circuits to determine a plurality of outputs from the plurality of resonance circuits. The ignition command signal of the inflator is obtained via an OR gate.

According to a second aspect of the present invention, there is provided an air bag device in which a resonance is provided at a relative position between an inflator for inflating and deploying an air bag disposed in a vehicle, and a portion of a vehicle body that is displaced at the initial stage of collision and a portion that is difficult to be displaced. A plurality of resonance circuits having a plurality of inductances that influence the conditions; and a plurality of comparison circuits that determine whether the plurality of outputs from the plurality of resonance circuits are larger than a predetermined threshold value, respectively. The output of the circuit is directed to the AND gate through an AND gate for the output compared to the low threshold from the multiple resonant circuits, and through the OR gate for the output compared to the high threshold from the multiple resonant circuits, and This is to obtain the ignition command signal of the inflator.

In the airbag device according to a third aspect of the present invention, the threshold value of the comparison circuit for comparing with the high threshold value from the plurality of resonance circuits is a threshold value that changes with the passage of time.

According to a fourth aspect of the present invention, in the airbag device, the relative positions of the portion of the vehicle body that is displaced at the initial stage of collision and the portion that is difficult to be displaced are set between the rocker panel and the seat frame, and the inner plate and the outer plate in the pillar. , Between the inner panel and the outer panel in the door, between the floor of a large vehicle and the reinforcement, and between the floor of a large vehicle and the front panel.

According to a fifth aspect of the airbag device, the resonance circuit is a frequency generating circuit or a filter.

According to a sixth aspect of the present invention, in the airbag device, the plurality of comparison circuits, which determine whether the plurality of outputs from the plurality of resonance circuits are larger than a predetermined threshold value, respectively, have a change output and a change from each resonance circuit. Speed output, the output of the plurality of comparison circuits, through the AND gate for the output comparing the change speed output from the plurality of resonance circuits and a low threshold, and also the change speed output from the plurality of resonance circuits The output compared with a high threshold value is selected via an OR gate, and the output from the plurality of resonant circuits is compared with a predetermined threshold value via an AND gate to obtain an ignition command signal for the inflator. .

[0013]

Embodiments of the present invention will be described below.

[First Embodiment] FIG. 1 is an explanatory view showing a mounting position of an airbag apparatus according to a first embodiment of the present invention to a vehicle body. FIG. 2 is a characteristic diagram showing an output signal of the eddy current displacement sensor of the airbag device according to the first embodiment of the present invention at the time of a side collision, and shows an output signal at the time of a right side collision. FIG. 3 is a perspective view showing a state in which the airbag device according to the first embodiment of the present invention is attached to a passenger seat.

The airbag device according to the present embodiment is arranged on the left and right sides of the interior of an automobile, for example, on the door sides of the driver's seat 3 and the passenger seat 5 of the vehicle body 1, and the side impact airbag device 8 (distributed to the passenger seat 5 respectively). (See FIG. 3 of the installed example), the side airbags contained therein are inflated and deployed by inflators (not shown) incorporated in the side collision airbag devices 8. In particular, the side airbag device 8 is
The casing is directly attached to the seat frame 7 of the passenger seat 5 with screws 6.

The airbag device of this embodiment uses the sensor shown in FIGS. 3 and 4 as a sensor for detecting the impact at the time of a collision. That is, as the sensor, an inner panel D formed of an inductance L formed of an air-core coil housed in a housing separately provided from the side impact airbag device 8 and an iron plate of a door facing the inductance L
The eddy current displacement sensors 2 and 4 that detect the change in the eddy current loss generated by the R as a change in the distance are used.
The eddy current displacement sensors 2 and 4 are installed in the driver's seat 3 and the driver's seat 3
And the passenger seat 5 and the door on the passenger seat 5 side.

Further, the eddy current type displacement sensor 4 on the passenger seat 5 side
Is composed of a rear eddy current displacement sensor 4A at the rear of the seat and a front eddy current displacement sensor 4B at the front of the seat. Similarly, although not shown, the eddy current displacement sensor 2 on the driver's seat 3 side is also composed of a rear eddy current displacement sensor behind the seat and a front eddy current displacement sensor in front of the seat.

Further, in this embodiment, as shown in FIG. 1, eddy current displacement sensors 2 and 4 are arranged on the left and right of the vehicle body 1. As a result, the eddy current displacement sensors 2 and 4 can detect the displacement of the vehicle body in the left-right direction. For example, the eddy current displacement sensor 2 generates a negative voltage as shown in FIG. 2 when a displacement to the left occurs when a right side collision occurs.
Further, when a displacement in the right direction occurs at the time of a left-side collision, the eddy current displacement sensor 4 produces the same output as in FIG. The polarities of the output signals generated by the eddy current displacement sensors 2 and 4 may be opposite to those shown in FIG.

Next, the sensor output circuit of the eddy current displacement sensors 2 and 4 of the airbag device of this embodiment will be described. Since the eddy current displacement sensors 2 and 4 have the same configuration, the eddy current displacement sensor 4 on the passenger seat 5 side will be described here.

FIG. 4 is a main part control circuit diagram for controlling the airbag apparatus according to the first embodiment of the present invention, and FIG.
FIG. 3 is an overall control circuit diagram for controlling the airbag device according to the first embodiment of the present invention.

In the figure, as a self-excited oscillation circuit of the present embodiment, an oscillation circuit 20 (20 comprising a Colpitts oscillation circuit is shown.
A, 20B) has an oscillation frequency f determined by the inductance L (LA, LB) and the capacitors C1 and C2, and this oscillation frequency f is f = √ {1 / L (C1.C2 / C1 + C2)}. / 2π and self-excited oscillation occurs at this oscillation frequency f. The value of the inductance L (LA, LB) is the inductance L
It is determined by the distance to the inner panel DR (DRA, DRB) made of the iron plate of the door facing (LA, LB).
The resistors R1 and R2 and the capacitor C3 are for obtaining the base current of the transistor T1, and the resistor R3 is an output resistor. The inductances L (LA, LB) are built in a non-magnetic housing that constitutes the rear eddy current displacement sensor 4A behind the seat and the front eddy current displacement sensor 4B in front of the seat. In particular, the inductance L (L
A, LB) and the inner panel DR (DRA, DRB) of the door facing the inductance L (LA, LB) of the eddy current displacement sensor 2,
4.

The rectifier circuit 21 comprises a diode D, a capacitor C4 and a resistor R4, the capacitor C4 is for smoothing, the resistor R4 is a discharge resistor, the ripple of the output rectified by the capacitor C4 is reduced, and the resistor R4 is used. The response of the output of the capacitor C4 is improved. The differentiating circuit 22 is composed of a capacitor C5 and a resistor R5 and differentiates the output of the rectifying circuit 21.

In FIG. 5, the inner panels DRA, DR
B, inductances LA and LB, oscillator circuits 20A and 20
B, rectifying circuits 21A and 21B, differentiating circuits 22A and 22B
Are the same circuit components as the inner panel DR, the inductance L, the oscillation circuit 20, the rectifying circuit 21, and the differentiating circuit 22 in FIG. 4, and the inner panels DRA and DRB, the inductances LA and LB, the oscillating circuits 20A and 20B, and the rectifying circuit. The inner panel DR, the inductance L, the oscillating circuit 20, the rectifying circuit 21, and the differentiating circuit 22 in FIG. 4 are used as 21A and 21B and the differentiating circuits 22A and 22B. In particular, the inner panels DRA and DRB mean the parts of the rear eddy current displacement sensor 4A behind the seat and the front eddy current displacement sensor 4B in front of the seat.

The comparing circuit COMP1 compares the output of the differentiating circuit 22A with a predetermined threshold value VTH1, and the differentiating circuit 2
It is "H" when the output of 2A is equal to or higher than the predetermined threshold VTH1, and is "0" when the output of the differentiating circuit 22A is lower than the predetermined threshold VTH1. Further, the comparison circuit COMP2 compares the output of the differentiating circuit 22A with a predetermined threshold value VTH2, and when the output of the differentiating circuit 22A is equal to or larger than the predetermined threshold value VTH2, "H", conversely, the output of the differentiating circuit 22A. Is less than the predetermined threshold value VTH2, it becomes "L". Here, the threshold value VTH1
And the threshold value VTH2 have a relationship of VTH1 <VTH2.

The comparison circuit COMP3 compares the magnitude of the output of the differentiating circuit 22B with a predetermined threshold value VTH3, and the differentiating circuit 2
When the output of 2B is greater than or equal to the predetermined threshold VTH3, it is "H", and conversely, when the output of the differentiating circuit 22B is less than the predetermined threshold VTH3, it is "L". Further, the comparison circuit COMP4 compares the output of the differentiating circuit 22B with a predetermined threshold value VTH4, and when the output of the differentiating circuit 22B is equal to or more than the predetermined threshold value VTH4, "H", conversely, the output of the differentiating circuit 22B. Is less than the predetermined threshold value VTH4, it becomes "L". Here, the threshold value VTH3
And the threshold value VTH4 have a relationship of VTH3 <VTH4.

Comparison circuit COMP1 and comparison circuit COMP3
Output of AND gate is AND gate AND1, and the output of AND gate AND1 is AND gate AND1.
It is used as one of the two inputs. In addition, the comparison circuit COMP2
And the output of the comparison circuit COMP4 are ORed by OR gate O
Further, the output of the OR gate OR is used as the other input of the AND gate AND2.

The output of the AND gate AND2 controls ON / OFF of the transistor T2. Usually transistor T2
Is off and transistor T2 is on,
The squib PS on the passenger seat 5 side ignites the inflator.

Next, the operation of the airbag device of the present embodiment constructed as described above will be explained.

Door inner panel DR (DRA, DRB
) And the inductances LA and LB built in the rear eddy current displacement sensor 4A behind the seat and the front eddy current displacement sensor 4B in front of the seat, when the distance is within a predetermined distance range. Inductance LA, LB
And the oscillation frequency f determined by the capacitors C1 and C2, the oscillation circuits 20A and 20B are in the oscillation state or the frequency state near the oscillation position. At this time, in the oscillator circuits 20A and 20B, as shown in FIG. 4, the maximum current or a current close to it flows through the transistor T1, and a predetermined voltage V is generated in the resistor R3 due to the voltage drop. The magnitude of V is at or near the maximum. Here, the maximum value of the voltage V or a value close to it is the inner panel DR (DRA, DRB)
And the rear eddy current displacement sensor 4A and the front eddy current displacement sensor 4B are determined by the difference in distance due to the mounting accuracy.

This voltage V is rectified by the diode D of the rectifier circuits 21A and 21B and charged in the capacitor C4. The resistor R4 is used to discharge the electric charge stored in the capacitor C4. The voltage V charged in the capacitor C4 is detected by the differentiating circuits 22A and 22B composed of the capacitor C5 and the resistor R5, and the change in the voltage charged in the capacitor C4 is detected.

The output of the differentiation circuit 22A is the comparison circuit COM.
It is input to P1 and the comparison circuit COMP2, compared with the threshold value VTH1 and the threshold value VTH2, and the output of the differentiation circuit 22B is
Input to the comparison circuit COMP3 and the comparison circuit COMP4,
The threshold value VTH3 and the threshold value VTH4 are compared. Comparison circuit COM
The outputs of P1 and the comparison circuit COMP3 are ANDed by the AND gate AND1, the output of the AND gate AND1 is used as one input of the AND gate AND2, and the outputs of the comparison circuit COMP2 and the comparison circuit COMP4 are ORed. Is taken by the OR gate OR, and the output of the OR gate OR is used as the other input of the AND gate AND2. Therefore, the outputs of the comparison circuits COMP1 and COMP3 are changed from "L" to "H" at the initial stage of the side impact because the threshold values VTH1 and VTH3 are set smaller than the threshold values VTH2 and VTH4. , Its output changes from "L" to "H". Further, depending on the side collision position, the comparison circuit CO
Either output of MP2 or comparison circuit COMP4 is "H"
Alternatively, both outputs become "H". At this time, the transistor T2 is turned on by the output of the AND gate AND2, and the squib PS on the passenger seat 5 side ignites the inflator.

Here, the threshold value VTH1 and the threshold value VTH3 are equal to the threshold value V
The reason why it is set smaller than TH2 and threshold VTH4 is
The reason is as follows.

That is, the comparison circuit COMP1 and the comparison circuit CO
As for the output of MP3, the threshold VTH1 and the threshold VTH3 are the threshold V
Since TH2 and threshold VTH4 are set smaller than threshold VTH4, both outputs are "H" when thresholds VTH1 and VTH3 of comparators COMP1 and COMP3 are exceeded in the initial stage of a side collision.
become. After that, the comparison circuit COMP2 and the comparison circuit COMP4, which compare the high threshold value VTH2 and the high threshold value VTH4, are either one of the rear eddy current displacement sensor 4A and the front eddy current displacement sensor 4B arranged near the side collision position. The output becomes "H" or both outputs become "H". At this time, the transistor T2 is turned on by the output of the AND gate AND2, and the squib PS on the passenger seat 5 side ignites the inflator. This makes it possible to perform detection that matches the characteristics of a normal side collision, and increase the reliability of side collision detection. Further, the rear eddy current displacement sensor 4A or the front eddy current displacement sensor 4B disposed near the side collision position enables side collision detection on a wide surface.

As described above, in the airbag device of this embodiment, the squib PS of the inflator for inflating and deploying the airbag (not shown) disposed in the vehicle, the portion which is displaced at the initial stage of the collision of the vehicle body 1, and the portion which is difficult to be displaced. A plurality of inductances LA and LB that are placed at a position relative to
And a plurality of comparator circuits COMP1 and COMP2 for judging whether the plurality of outputs from the plurality of oscillator circuits 20A and 20B each have a threshold value greater than a predetermined threshold value VTH1, VTH2, VTH3, VTH4. , CO
MP3, COMP4 and the plurality of comparison circuits COMP
1, COMP2, COMP3, COMP4 outputs the low threshold VTH1 from the plurality of oscillation circuits 20A, 20B.
, AND gate AND1 for output compared with VTH3
Via the plurality of oscillation circuits 20A, 20B
From the high thresholds VTH2 and VTH4, which are led to an AND gate AND2 via an OR gate OR, and the switching control of the transistor T2 for obtaining the ignition command signal of the squib PS of the inflator is performed. AND gate AND1, OR gate OR, AND gate AND2
, And an ignition circuit composed of a transistor T2, which can be an embodiment corresponding to claim 2.

Therefore, with the inner panel DR of the door,
By arranging the rear eddy current displacement sensor 4A behind the seat and the front eddy current displacement sensor 4B in front of the seat, it is possible to detect a side impact in a relatively wide range corresponding to almost the entire inner panel DR. In addition, the rear eddy current type displacement sensor 4A
When an umbrella, a metal rod, or the like is dropped near the front eddy current displacement sensor 4B and the front eddy current displacement sensor 4B, it is unlikely that both rear eddy current displacement sensors 4A and front eddy current displacement sensor 4B will detect it. Moreover, if the probability that a predetermined drop velocity is obtained and the outputs of the comparison circuit COMP2 and the comparison circuit COMP4 are “H” at the same time is assumed, the probability that the umbrella, the metal rod, etc. will fall will be very small. It will be reliable.

When the inner panel DR is gradually bent inward due to contact or the like when entering the garage, the distance between the inner panels DRA and DRB and the inductances LA and LB is gradually changed. Depending on the values of the inductances LA and LB, the oscillating circuits 20A and 20B leave the oscillating state or move away from the resonance point. However, the change in voltage of the rectifier circuits 21A and 21B changes slowly,
The threshold VTH1 in the comparison circuit COMP1 and the comparison circuit COMP2
And the threshold value VTH2, the comparison circuit COMP3
Even if the comparison circuit COMP4 compares the threshold value VTH3 and the threshold value VTH4 with each other, both cannot be set to "H" at the same time, so that the inflator on the passenger seat 5 side does not ignite. That is, when the inner panel DR is gradually bent inward due to contact or the like when entering the garage, the inflator does not ignite.

According to this embodiment, the inner panel DR
A, DRB, the rear eddy current displacement sensor 4A, and the front eddy current displacement sensor 4B are attached to each other according to the mounting accuracy of the voltage V
However, the error of the distance between the inner panels DRA, DRB and the inductances LA, LB depends on the setting of Q of the resonance condition, the diameter and the number of windings of the inductances LA, LB, and the current. That is, the mounting error can be reduced. In addition, even if the sensitivity is increased so as to increase the Q of these resonance conditions, the inner panels DRA and DRB detect the bending speed that bends inward, so there is no influence of mounting error. Absent.
When the self-sustained pulsation is maintained in the normal state and the self-sustained pulsation is not maintained, the inner panels DRA, DRB determine the collision by the inward bending speed, so that the side surface is put in a garage or the like. It does not work when contacted. Further, since the oscillation is always maintained by itself and the change of the inner panels DRA and DRB facing each other is detected, it is possible to constantly monitor a predetermined wide range, and highly reliable detection is possible. In addition, the oscillator circuit 20A,
Since the self-excited oscillation circuit is used in 20B, there is no need to add a circuit element for forced oscillation from the outside, and the circuit can be simplified.

In the present embodiment, the passenger seat 5 has been described, but the passenger seat 5 or the rear seat can be similarly arranged.

[Second Embodiment] FIG. 6 is an overall control circuit diagram for controlling an airbag apparatus according to a second embodiment of the present invention. In the drawings, the same reference numerals and symbols as those of the first embodiment show the same or corresponding constituent parts as those of the first embodiment, and therefore, duplicate description is omitted here, and their differences Only explained.

In the figure, a NAND gate NAND takes a logical product of the outputs of the comparison circuit COMP1 and the comparison circuit COMP3. When the logical product is "H", the transistor T3 is turned on to turn on the transistor T3. Negative logic is used according to the characteristics of. Of course, when the output of the NAND gate NAND is "H", the transistor T3 is off, and when the output of the NAND gate NAND is "L", the transistor T3 is on. In addition, the comparison circuit COMP2
And the output of the comparison circuit COMP4 are ORed by OR gate O
It is taken by R, and the output thereof controls on / off of the transistor T4.

That is, in this embodiment, the transistor T
ANDed with 3 and transistor T4,
When both the transistor T3 and the transistor T4 are turned on, the squib PS on the passenger seat 5 side ignites the inflator.

As described above, the airbag apparatus according to the present embodiment includes the squib PS of the inflator (not shown) for inflating and deploying the airbag, which is disposed in the vehicle, the portion which is displaced at the initial stage of the collision of the vehicle body 1, and the portion which is difficult to be displaced. A plurality of oscillation circuits 20A and 20B having a plurality of inductances LA and LB that influence the resonance condition, and a plurality of outputs from the plurality of oscillation circuits 20A and 20B are respectively set to predetermined threshold values VTH1 and VTH2. , VTH3, VTH4, a plurality of comparison circuits COMP1, COMP2, COM
P3, COMP4 and the plurality of comparison circuits COMP1,
The outputs of COMP2, COMP3 and COMP4 are set to the low threshold values VTH1 and VTH from the plurality of oscillation circuits 20A and 20B.
The output compared with TH3 is led to the transistor T3 through a NAND gate NAND which takes an AND gate disagreement, and the output compared with the high thresholds VTH2 and VTH4 from the plurality of oscillator circuits 20A and 20B is also supplied via an OR gate OR. A transistor T3 for leading to the transistor T4 to obtain an ignition command signal for the squib PS of the inflator, a NAND gate NAND for controlling switching of the transistor T4, an OR gate OR, a transistor T3,
An ignition circuit including a transistor T4 is provided, which can be an embodiment corresponding to claim 2.

Since the basic operation and operational effect are the same as those of the first embodiment, the description thereof will be omitted.

In particular, the difference is that, in this embodiment, the squib PS on the passenger seat 5 side cuts off both inputs by the transistor T3 and the transistor T4 which take the logical product, so that the squib PS is on the power source side or the ground. Even if it is short-circuited to the side, the inflator will not be ignited.

In the present embodiment, the passenger seat 5 has been described, but the driver seat 3 side or the rear seat side can be similarly arranged.

[Third Embodiment] FIG. 7 is an overall control circuit diagram for controlling an airbag apparatus according to a third embodiment of the present invention. In the drawings, the same reference numerals and symbols as those of the first embodiment show the same or corresponding constituent parts as those of the first embodiment, and therefore, duplicate description is omitted here, and their differences Only explained.

In the first embodiment shown in FIG. 5 and the second embodiment shown in FIG. 6, the comparison circuit COMP2 and the comparison circuit COMP4 set the magnitude of the output of the differentiating circuit 22A or the differentiating circuit 22B to a predetermined value. Threshold VTH2 or threshold VTH4 of VTH2 <VTH
1 and VTH4 <VTH3. However, as shown in FIG. 2, the characteristics such as the side collision of the vehicle show that a steep rise occurs several times before reaching the peak point, and the rise speed decreases during that period. Further, there is a possibility that the umbrella and other metal products may be dropped simultaneously onto the rear eddy current displacement sensor 4A behind the seat and the front eddy current displacement sensor 4B ahead of the seat. It is necessary not to detect this as noise.

Therefore, when the rear eddy current displacement sensor 4A on the rear side of the seat and the front eddy current displacement sensor 4B on the front side of the seat simultaneously detect a predetermined displacement speed, when a predetermined time elapses, The threshold value VTH2 or the threshold value VTH4 of the comparison circuit COMP2 and the comparison circuit COMP4 can be lowered to determine whether or not the continuous displacement is detected, thereby improving the reliability of the detection.

That is, the comparison circuit COMP1 and the comparison circuit CO
Upon receiving the output of the AND gate AND1 which is the logical product of MP3, the CR circuit of the resistor r11 and the capacitor C11 starts charging the capacitor C11. At the same time, the CR circuit of the resistor r21 and the capacitor C21 starts charging the capacitor C21. This time constant is set by setting conditions such as the setting positions of the rear eddy current displacement sensor 4A behind the seat and the front eddy current displacement sensor 4B in front of the seat and the strength of the mounting member.

The CR circuit of the resistor r11 and the capacitor C11 causes the transistor T11 to move as the charging of the capacitor C11 progresses.
Is turned on, and CR of resistor r21 and capacitor C21
The circuit turns on the transistor T21 as the charging of the capacitor C21 progresses. The transistor T11 is turned on until the threshold voltage of the comparison circuit COMP3 has reached Vccr13 / (r13 + r1) by the series circuit of the resistors r13 and r14.
The voltage of 4) was applied because the resistance r12 was changed to the resistance r13.
The threshold voltage drops by the amount of parallel connection to the. Similarly,
The transistor T21 is turned on until then until the comparison circuit COMP.
As the threshold voltage of 4, the voltage of Vcc · r23 / (r23 + r24) was applied by the series circuit of the resistor r23 and the resistor r24, but the threshold voltage drops by the amount that the resistor r22 is connected in parallel with the resistor r23. .

The outputs of the comparison circuit COMP2 and the comparison circuit COMP4 are input to one of the AND gates AND2 via the OR gate OR, and the AND gate AND2.
ON / OFF of the transistor T2 is controlled by "H" which coincides with the AND gate AND1 input to the other of the two. Normally, the transistor T2 is off, and when the transistor T2 is on, the squib P on the passenger seat 5 side is
The inflator is ignited by S.

Here, C of the resistor r11 and the capacitor C11
The R circuit, the series circuit of the resistors r13 and r14, the resistor r12, and the transistor T11 configure the timed threshold circuit Tim1 in the present embodiment. Similarly, the CR circuit of the resistor r21 and the capacitor C21, the series circuit of the resistor r23 and the resistor r24, the resistor r22, and the transistor T21 constitute the timed threshold circuit Tim2 in the present embodiment.

Next, the operation of the airbag device of the present embodiment constructed as described above will be explained.

The inductance LA built in the inner panel DR of the door, the rear eddy current displacement sensor 4A behind the seat and the front eddy current displacement sensor 4B in front of the seat.
, LB, when the distance is within a predetermined distance range, the values of the inductances LA, LB and the capacitor C at that time
At the oscillation frequency f determined by 1 and the capacitor C2, the oscillation circuits 20A and 20B are in the oscillation state or the frequency state near the oscillation. At this time, the oscillator circuits 20A and 20B
As shown in FIG. 4, a maximum current or a current close to it flows in the transistor T1, and a predetermined voltage V is generated in the resistor R3 due to the voltage drop. It is close to the value. here,
The maximum value of the voltage V or a value close to it is determined by the mounting accuracy between the inner panel DR, the rear eddy current displacement sensor 4A and the front eddy current displacement sensor 4B. This voltage V is rectified by the diode D of the rectifier circuits 21A and 21B and charged in the capacitor C4. Further, the voltage V charged in the capacitor C4 is the differential circuit 22A, 22B composed of the capacitor C5 and the resistor R5.
Then, a change in the voltage charged in the capacitor C4 is detected.

The output of the differentiation circuit 22A is the comparison circuit COM.
It is input to P1 and compared with the threshold value VTH1, and the output of the differentiating circuit 22B is input to the comparison circuit COMP3 and compared with the threshold value VTH3. Comparison circuit COMP1 and comparison circuit C
The output of OMP3 is ANDed by AND gate AND1 and the output of AND gate AND1 is used as one input of AND gate AND2. In addition, the differentiating circuit 22
The output of A is input to the comparison circuit COMP2, and the differentiation circuit 2
The output of 2A is input to the comparison circuit COMP4. In the comparison circuit COMP2, the comparison circuit COMP1 and the comparison circuit CO
Upon receiving the output of the AND gate AND1 which is the logical product of MP3, the CR circuit of the resistor r11 and the capacitor C11 starts charging the capacitor C11. Meanwhile, the transistor T
11 is off, and the threshold voltage determined by the series circuit of the resistors r13 and r14 is applied as the threshold voltage of the comparison circuit COMP3. Then, the CR circuit of the resistor r11 and the capacitor C11 is
The transistor T11 is turned on and the comparison circuit COM
As the threshold voltage of P4, the threshold voltage divided by the series circuit of the resistor r13 and the resistor r14 was applied, but the threshold voltage drops as much as the resistor r12 is connected in parallel to the resistor r13. The output of the comparison circuit COMP2 is supplied to the other input of the AND gate AND2 via the OR gate OR.

Then, in the comparison circuit COMP4, the CR circuit of the resistor r21 and the capacitor C21 receives the output of the AND gate AND1 and starts charging the capacitor C21.
During this period, the transistor T21 is off and the comparison circuit COMP
As the threshold voltage of 4, the threshold voltage determined by the series circuit of the resistor r23 and the resistor r24 is applied. And
The CR circuit of the resistor r21 and the capacitor C21 is the capacitor C
As the charging of 21 proceeds, the transistor T21 is turned on,
Until then, as the threshold voltage of the comparison circuit COMP4, the resistance r
The threshold voltage divided by the series circuit of 23 and the resistor r24 was applied, but the threshold voltage drops by the amount that the resistor r22 is connected in parallel with the resistor r23. The output of the comparator circuit COMP4 goes through an OR gate OR and an AND gate AND2.
And the other input.

Therefore, the outputs of the comparison circuits COMP2 and COMP4, and the comparison circuits COMP1 and COM in which the threshold values VTH1 and VTH3 are set to be small.
The on / off control of the transistor T2 is performed by the AND gate AND2 to which the output of MP3 is input. Normal,
The transistor T2 is off, and when the transistor T2 is on, the squib PS on the passenger seat 5 side ignites the inflator.

When the vehicle is put in a garage or the like, the inner panel DR gradually bends inward due to contact or the like, so that the distance between the inner panels DRA and DRB and the inductances LA and LB gradually changes. Inductances LA and LB at this time
Depending on the value of, the oscillating circuits 20A and 20B leave the oscillating state or move away from the resonance point. However, the rectifier circuit 21
The changes in the voltages of A and 21B change gently, and the inflator on the passenger seat 5 side does not ignite.

Therefore, with the inner panel DR of the door,
By arranging the rear eddy current displacement sensor 4A behind the seat and the front eddy current displacement sensor 4B in front of the seat, it is possible to detect a side impact in a relatively wide range corresponding to almost the entire inner panel DR. In addition, the rear eddy current type displacement sensor 4A
When an umbrella, a metal rod, or the like is dropped near the front eddy current displacement sensor 4B and the front eddy current displacement sensor 4B, it is unlikely that both rear eddy current displacement sensors 4A and front eddy current displacement sensor 4B will detect it. In addition, since there is no possibility that the drop will be continued until the confirmation is made after a predetermined time delay, the probability that the umbrella, the metal rod, and the like will fall will be very low, and the reliability will be high.

As described above, the airbag apparatus according to the present embodiment has the squib PS of the inflator (not shown) for inflating and deploying the airbag, which is disposed in the vehicle, the portion which is displaced at the initial stage of the collision of the vehicle body 1, and the portion which is difficult to be displaced. A plurality of oscillation circuits 20A and 20B having a plurality of inductances LA and LB that influence the resonance condition, and a plurality of outputs from the plurality of oscillation circuits 20A and 20B are respectively set to predetermined threshold values VTH1 and VTH2. , VTH3, VTH4, a plurality of comparison circuits COMP1, COMP2, COM
P3, COMP4 and the plurality of comparison circuits COMP1,
The outputs of COMP2, COMP3 and COMP4 are set to the low threshold values VTH1 and VTH from the plurality of oscillation circuits 20A and 20B.
The output compared with TH3 is led to the AND gate AND2 via the AND gate AND1, and the output compared with the high threshold values VTH2 and VTH4 from the plurality of oscillation circuits 20A and 20B is led to the AND gate AND2 via the OR gate OR, and the AND gate AN for switching control of transistor T2 for obtaining ignition command signal of squib PS
D1, an OR gate OR, an AND gate AND2, and an ignition circuit composed of a transistor T2.
This can be an embodiment corresponding to claim 2.

According to this embodiment, the inner panel DR
The magnitude of the voltage V is determined by the mounting accuracy between the rear eddy current displacement sensor 4A and the front eddy current displacement sensor 4B. The resonance condition Q is set and the inductances LA, LB are determined. It is possible to reduce the error in the distance between the inner panel DR and the inductances LA and LB, that is, the mounting error, depending on the diameter, the number of windings, and the current. However, even if the sensitivity is increased so as to increase the Q of these resonance conditions, the inner panels DRA, DRB
Since it detects the inward bending speed, it is completely unaffected by mounting errors. When the self-sustained pulsation is maintained in the normal state and the self-sustained pulsation is not maintained, the inner panels DRA, DRB determine the collision by the inward bending speed, so that the side surface is put in a garage or the like. It does not work when contacted. Furthermore,
Inner panel DRA that always keeps oscillating by itself and opposes
, DRB changes are detected, so that a wide predetermined range can be constantly monitored, and highly reliable detection is possible. Further, since the self-excited oscillation circuit is used for the oscillation circuits 20A and 20B, there is no need to add a circuit element for forced oscillation from the outside, and the circuit can be simplified.

In particular, in this embodiment, the threshold values of the comparator circuits COMP2 and COMP4 to be compared with the high threshold values from the plurality of oscillator circuits 20A and 20B are the CR circuit of the resistor r11 and the capacitor C11, the resistor r13 and the resistor r14. The time series threshold circuit Tim1 in the present embodiment, the CR circuit of the resistance r21 and the capacitor C21, the series circuit of the resistance r23 and the resistance r24, the resistance r22, and the transistor T21 in the present embodiment. The time-limit threshold circuit Tim2 in the embodiment is configured to be thresholds VTH2 and VTH4 that change with the passage of time, and this can be taken as a measure for implementation according to claim 3.

Therefore, the rear eddy current type displacement sensor 4A
When an umbrella, a metal rod, or the like is dropped near the front eddy current displacement sensor 4B and the front eddy current displacement sensor 4B, it is unlikely that both rear eddy current displacement sensors 4A and front eddy current displacement sensor 4B will detect it. In addition, since there is no possibility that the drop will be continued until the confirmation is made after a predetermined time delay, the probability that the umbrella, the metal rod, and the like will fall will be very low, and the reliability will be high.

Although the passenger seat 5 has been described in the present embodiment, the passenger seat 5 may be similarly arranged on the driver seat 3 side or the rear seat side. Further, although the present embodiment has been described on the premise of the airbag device, when the present invention is carried out, the present invention is not limited to a side collision and can be used.

[Fourth Embodiment] FIG. 8 is an overall control circuit diagram for controlling an airbag apparatus according to a fourth embodiment of the present invention. In the drawings, the same reference numerals and symbols as those of the first embodiment show the same or corresponding constituent parts as those of the first embodiment, and therefore, duplicate description is omitted here, and their differences Only explained.

In this embodiment, the outputs are obtained from the rectifier circuit 21A and the rectifier circuit 21B as compared with the first embodiment.

That is, the comparison circuit COMP11 compares the output of the rectifier circuit 21A with a predetermined threshold value VTH11, and when the output of the rectifier circuit 21A is equal to or higher than the predetermined threshold value VTH11,
"1", conversely, the output of the rectifier circuit 21A is the predetermined threshold value VTH
When it is less than 11, it is “0”. Comparison circuit COMP12
Indicates that the output of the rectifier circuit 21B has a predetermined threshold value VTH12.
In comparison, when the output of the rectifier circuit 21B is equal to or higher than the predetermined threshold VTH12, the value is "1", and conversely, when the output of the rectifier circuit 21B is lower than the predetermined threshold VTH12, the value is "0". Comparison circuit CO
The outputs of MP11 and the comparison circuit COMP12 are ANDed by the AND gate AND11, and the output is led to the AND gate AND2.

Next, the operation of the side airbag device 10 of the present embodiment added as described above will be described.

When the rocker panel DR gradually bends inward due to contact, collision, etc., and the distance between the rocker panel DR and the inductance L gradually changes, the oscillation circuits 20A and 20B oscillate depending on the value of the inductance L at that time. Or goes away from the resonance point, the output current decreases from the maximum current value or a current value close to it, and the output voltage V decreases.

The output voltage V of the oscillating circuit 20A is rectified by the rectifying circuit 21A, and the rectified voltage is the comparison circuit CO.
It is compared with the threshold value VTH11 at MP11, and the oscillation circuit 20
The output voltage V of B is rectified by the rectifier circuit 21B, and the rectified voltage is compared with the threshold value VTH12 by the comparator circuit COMP12. It becomes "1" when the outputs of both rectifier circuits 21A and 21B are above the predetermined threshold values VTH11 and VTH12, and conversely becomes "0" when the outputs of the rectifier circuits 21A and 21B are below the predetermined threshold values VTH11 and VTH12. The comparison circuit COMP11, C
The output of the OMP12 is logically ANDed by the AND gate AND11, and further, the AND gate AND2 is used for the comparison circuit COM.
The output of the AND gate AND1 compared with the low threshold values VTH1 and VTH3 at P1 and COMP3, and the comparison circuit COMP2.
The output of the OR gate OR is compared with the high threshold values VTH2 and VTH4 by COMP4, and the logical product is obtained, and the transistor T2
When the transistor T2 is turned on, the squib PS on the passenger seat 5 side ignites the inflator.

As described above, in the present embodiment, the embodiment corresponding to claim 2, that is, the comparison circuit COMP.
1, COMP2, COMP3, COMP4 outputs the low threshold VTH1 from the plurality of oscillation circuits 20A, 20B.
, AND gate AND1 for output compared with VTH3
Via the plurality of oscillation circuits 20A, 20B
From the high thresholds VTH2 and VTH4, which are led to an AND gate AND2 via an OR gate OR, and the switching control of the transistor T2 for obtaining the ignition command signal of the squib PS of the inflator is performed. AND gate AND1, OR gate OR, AND gate AND2
, An ignition circuit including a transistor T2, and further, a plurality of comparison circuits COMP11 and COMP12 for judging whether or not a plurality of outputs from the plurality of oscillation circuits 20A and 20B are larger than predetermined threshold values VTH11 and VTH12, respectively. An AND gate AN is used to compare the output of the plurality of comparison circuits COMP11 and COMP12 with the change speed output from the plurality of oscillation circuits 20A and 20B and a low threshold value, which are the change output and the change speed output from each of the oscillation circuits 20A and 20B.
D1 and the output of the plurality of oscillator circuits 20A, 20B compared with the change speed output and the high threshold values VTH2, VTH4 via the OR gate OR, and the output from the plurality of oscillator circuits 20A, 20B. Threshold VTH1
, AND gate AND1 for output compared with VTH3
And an ignition circuit for obtaining an ignition command signal of the inflator by leading the AND gate AND2 to the AND gate AND2, which can be an embodiment of claim 6.

Therefore, in the embodiment of claim 2, a plurality of inductances L having a plurality of inductances L, which determine resonance conditions, are provided at relative positions of a portion of the vehicle body 1 that is displaced at the initial stage of collision and a portion that is difficult to be displaced. Oscillation circuits 20A, 20B
Is to confirm the magnitude of the change output from the comparator circuit COMP1, COMP2, COMP3, COMP.
It is difficult to make a determination based on the magnitude of the change speed output of 4, and an external force is applied from the outside by human power or the like, and elastically changes once, but it is possible to make a reliable determination of the external force or the like restored by the elastic force. it can.

In this embodiment, the AND gate AND2 determines the magnitude of the change output from the plurality of oscillator circuits 20A and 20B. However, a plurality of oscillator circuits are provided in the AND gate AND1 or the OR gate OR. 20
You may input the determination result of the magnitude | size of the change output from A, 20B. It is possible to expect improved reliability at this time as well, and also to set each threshold value so that it will not operate due to collision of bounced pebbles, door scraping, door scraping during garage parking, etc. it can. Further, it is possible to eliminate the possibility that the airbag device will operate even when traveling at low speed where the airbag device does not need to operate.

As described above, the common aspect of the embodiments is to increase the area to be detected as the side collision target by taking the logical sum of the outputs of the plurality of oscillation circuits 20A and 20B.

That is, the airbag device of each embodiment is
A plurality of inductors LA, which are disposed in the vehicle, are disposed at the relative positions of the squib PS of an inflator (not shown) for inflating and deploying an airbag, and a portion that is displaced in the initial stage of collision of the vehicle body 1 and a portion that is difficult to displace. , LB, and a plurality of outputs from the plurality of oscillator circuits 20A, 20B, each having a predetermined threshold value V.
A plurality of comparison circuits COMP2, COMP4 for judging whether or not it is larger than TH2, VTH4, and the plurality of comparison circuits COM
The output of P2 and COMP4 is provided with an ignition circuit that obtains an ignition command signal of the squib PS of the inflator via the OR gate OR, and this can be an embodiment corresponding to claim 1.

Therefore, the plurality of oscillator circuits 20A, 20
By taking the logical sum of the outputs of B, the area to be detected as the side collision target can be enlarged, and the two rear eddy current displacement sensors 4A and front eddy current displacement sensors 4B in the above-described embodiment can be used. It is not limited, and three or more sensors can be used by taking the logical sum as a basic configuration. Thereby, the inner panels DRA and DRB of the door, the rear eddy current displacement sensor 4A behind the seat and the front eddy current displacement sensor 4B in front of the seat.
With the above arrangement, it is possible to detect a side impact in a relatively wide range corresponding to the entire inner panel DR.

The relative position between the portion of the vehicle body 1 that is displaced in the initial stage of the collision and the portion that is difficult to displace is between the rocker panel DR and the seat frame 7. This is the same as the embodiment of claim 3. can do. In this type of embodiment, the device is easy to set up. However, in the case of implementing the present invention, between a rocker panel and a seat frame, between an inner plate and an outer plate in a pillar, between an inner panel and an outer panel in a door, a large vehicle such as a truck or a bus. It is possible to arrange any one or more between the floor and the reinforcement, and between the floor of the large vehicle and the front panel.

In the above embodiment, the oscillation circuits 20A, 20
Although the distance between the inductance L and the inner panels DRA and DRB was monitored by the self-excited oscillation of B, when the present invention is implemented, the change in the distance between the inductances LA and LB and the inner panels DRA and DRB resonates. Since the collision is determined when the conditions are changed and the resonance condition is deviated, when the present invention is carried out, in addition to using the oscillation circuits 20A and 20B as in the above embodiment, the resonance current is detected. The distance between the inductances LA and LB and the inner panels DRA and DRB can also be monitored by.

That is, the oscillator circuit 2 for carrying out the present invention.
0A and 20B are detections as to whether or not the resonance point can be maintained, and can be a resonance circuit that determines the resonance condition.

As described above, the resonance circuit for carrying out the present invention can be a frequency generating circuit or a filter, and this can be the embodiment of claim 5. In this type of embodiment, a self-excited or separately-excited oscillation circuit can be used as a circuit, and it can also be used as a filter. Therefore, the circuit configuration is simple, and the inner panel DR is partially provided in the circuit. Since a mechanical structure is incorporated between the seat frame 7 and the seat frame 7, no special structure is required as a sensor.

By the way, although the side airbag device 10 has been described in the above embodiment, the present invention is not limited to the side airbag device 10 and can be used in general airbag devices. In particular, it can be applied to large vehicles with few crash zones such as trucks and buses.

Further, in the above embodiment, the embodiment in which the ignition control circuit is incorporated in the side airbag device 10 has been described. However, in the case of implementing the present invention, the side airbag device 10 and the ignition control circuit are Can be separately provided. In particular, the ignition control circuit can be incorporated into the interior space of the door or the interior space of the seat.

In the above embodiment, the oscillation circuit 20
As the Colpitts oscillator circuit, a Hartley oscillator circuit, a Clapp oscillator circuit, a transistor-coupled oscillator circuit, or the like can be used when the present invention is implemented. In particular, the Colpitts oscillator circuit has one inductance L, but the Hartley oscillator circuit having two inductances enables a wider range of sensing.

It should be noted that in the embodiment shown in FIG.
Although the case of application of the embodiment shown in FIG. 6 has been described, when the present invention is implemented, it can be similarly used as application of the embodiment shown in FIGS. 6 and 7. That is, when the present invention is implemented, for example, a plurality of oscillator circuits 20A and 20B are used.
If at least one of the judgment results of the magnitude of the change output is introduced into a logic circuit that first obtains a logical product or a logical sum,
The reliability can be expected to be improved, and further, it is possible to set the respective threshold values so as not to operate due to a collision of bounced pebbles, a door scraping, a door scraping when entering a garage, and the like. Further, it is possible to eliminate the possibility that the airbag device will operate even when traveling at low speed where the airbag device does not need to operate.

[0085]

As described above, in the airbag device according to the first aspect of the present invention, the inflator arranged to inflate and deploy the airbag disposed in the vehicle, and the portion of the vehicle body which is displaced at the initial stage of collision and the portion which is difficult to be displaced are relatively disposed. And a plurality of resonance circuits having a plurality of inductances that influence the resonance condition arranged at a position,
Each of the plurality of outputs from the plurality of resonant circuits is determined,
A plurality of outputs from the plurality of resonance circuits are ORed to obtain an ignition command signal for the inflator.

Therefore, by taking the logical sum of the outputs of the plurality of resonance circuits, the area to be detected as the side collision target can be expanded, and by taking the logical sum as the basic configuration, three or more sensors can be obtained. It can also be used and can detect a relatively wide range of side impacts.

The airbag device according to a second aspect of the present invention has a resonance condition in which the inflator for inflating and deploying the airbag disposed in the vehicle is disposed at a relative position between a portion of the vehicle body which is displaced at the initial stage of collision and a portion which is difficult to be displaced. A plurality of resonance circuits having a plurality of inductances that influence the above, and a plurality of comparison circuits that determine whether each of the plurality of outputs from the plurality of resonance circuits is greater than a predetermined threshold value. Through the AND gate for the output compared to the low threshold from the plurality of resonant circuits, and through the OR gate for the output compared to the high threshold from the plurality of resonant circuits, to the AND gate, The ignition command signal of the inflator is obtained.

Therefore, the logical sum of the outputs of the plurality of resonant circuits being equal to or higher than the predetermined high threshold value and the logical product of the output of the plural resonant circuits being equal to or higher than the predetermined low threshold value are obtained. The area to be detected as the side collision target can be expanded, and a relatively wide range can be detected with high reliability. Further, when an umbrella, a metal rod, or the like is dropped, there is little possibility of simultaneous detection, and the output of a plurality of resonant circuits is equal to or higher than a predetermined high threshold value due to the magnitude of a predetermined drop speed, and The probability that the outputs of the plurality of resonance circuits are equal to or higher than a predetermined low threshold value is low, and the probability that the umbrella circuit, the metal rod, and the like will drop is very low, and the reliability is high.

According to the third aspect of the present invention, the threshold value of the comparison circuit for comparing with the high threshold value from the plurality of resonance circuits is a threshold value which changes with the passage of time. In addition to the effect of claim 1 or claim 2,
If you drop an umbrella, metal rod, etc., there is no possibility that the drop will continue until you confirm it with a predetermined time delay,
It is highly reliable because it has a very low probability of operating when an umbrella, metal rod, etc. falls.

According to the airbag device of claim 4, the relative position between the portion of the vehicle body that is displaced at the initial stage of collision and the portion that is difficult to be displaced is
Between the rocker panel and the seat frame, between the inner and outer plates in the pillars, between the inner and outer panels in the doors, between the floor of large vehicles and the reinforcement, the floor and front panels of large vehicles. And the setting of the airbag device is easy, in addition to the effect according to any one of claims 1 to 3.
Operation reliability can be improved.

The resonance circuit of the airbag device according to claim 5 is:
It is a frequency generating circuit or a filter. Therefore, in addition to the effect according to any one of claims 1 to 4, a self-excited or separately-excited oscillation circuit can be used, and it can be used as a filter. Since it is easy and a mechanical structure is incorporated in a part of the circuit, no special structure is required as a sensor.

According to another aspect of the airbag device of the present invention, the plurality of comparison circuits, which determine whether the plurality of outputs from the plurality of resonance circuits are larger than a predetermined threshold value, respectively, have a change output and a change speed from each resonance circuit. The output of the plurality of comparison circuits is compared with the change speed output from the plurality of resonance circuits and a low threshold value through an AND gate, and the output of the plurality of comparison circuits is higher than the change speed output from the plurality of resonance circuits. Via the OR gate for the output compared to the threshold, and
The output from the plurality of resonance circuits and the output compared with a predetermined threshold value are selected via an AND gate to obtain the ignition command signal of the inflator. Therefore, any one of claims 2 and 5 In addition to the effect described in one, the form of external force, for example, the possibility of operating in the collision of bounced pebbles, door scraping, door scraping during garage parking, etc.
It is possible to eliminate the possibility that the airbag device will operate at low speeds that do not need to operate.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a mounting position of an airbag device according to a first embodiment of the present invention to a vehicle body.

FIG. 2 is a characteristic diagram showing an output signal at the time of a side collision of the eddy current displacement sensor of the airbag device according to the first embodiment of the present invention, and shows an output signal at the time of a right side collision. .

FIG. 3 is a perspective view showing a state in which the airbag device according to the first embodiment of the present invention is attached to a passenger seat.

FIG. 4 is a main-part control circuit diagram for controlling the airbag device according to the first embodiment of the present invention.

FIG. 5 is an overall control circuit diagram for controlling the airbag device according to the first embodiment of the present invention.

FIG. 6 is an overall control circuit diagram for controlling an airbag device according to a second embodiment of the present invention.

FIG. 7 is an overall control circuit diagram for controlling an airbag device according to a third embodiment of the present invention.

FIG. 8 is an overall control circuit diagram for controlling an airbag device according to a fourth embodiment of the present invention.

[Explanation of symbols]

 PS Inflator squib DR, DRA, DRB Inner panel L, LA, LB Inductance COMP1-COMP4 Comparison circuit 4, 4A, 4B Eddy current displacement sensor 20, 20A, 20B Oscillation circuit 21, 21A, 21B Rectification circuit 22, 22A, 22B differentiation circuit

Claims (6)

[Claims] 1. An inflator for inflating and deploying an airbag arranged inside a vehicle, and a plurality of inductances arranged at relative positions between a portion of a vehicle body that is displaced at the initial stage of collision and a portion that is difficult to displace, and a plurality of inductances that influence resonance conditions. A plurality of resonance circuits having, respectively judging a plurality of outputs from the plurality of resonance circuits,
An airbag circuit, comprising: an ignition circuit that obtains an ignition command signal for the inflator by ORing a plurality of outputs from the plurality of resonance circuits. 2. An inflator for inflating and deploying an airbag arranged inside a vehicle, and a plurality of inductances arranged at a relative position between a portion of a vehicle body that is displaced at the initial stage of collision and a portion that is difficult to displace are provided with a plurality of inductances. A plurality of resonance circuits having, a plurality of comparison circuits for determining whether each of the plurality of outputs from the plurality of resonance circuits is greater than a predetermined threshold value, and outputs of the plurality of comparison circuits from the plurality of resonance circuits. Ignition circuit for obtaining an ignition command signal of the inflator, which is led to an AND gate through an AND gate for an output compared with a low threshold value of, and through an OR gate for an output compared with a high threshold value from the plurality of resonance circuits. An airbag device comprising: 3. The threshold according to claim 1, wherein the threshold of the comparison circuit for comparing with the high threshold from the plurality of resonance circuits is a threshold that changes with the passage of time. Airbag device. 4. The relative positions of the portion of the vehicle body that is displaced at the initial stage of the collision and the portion that is difficult to be displaced are determined between the rocker panel and the seat frame, between the inner plate and the outer plate in the pillar, and the inner member in the door. 4. A panel and an outer panel, a floor of a large vehicle and a reinforcement, and a floor of a large vehicle and a front panel, which are any one of claims 1 to 3. The airbag device described. 5. The resonance circuit is a frequency generation circuit or a filter.
The airbag device according to any one of 1. 6. A plurality of comparison circuits that determine whether each of the plurality of outputs from the plurality of resonance circuits is larger than a predetermined threshold value is a change output and a change speed output from each resonance circuit, and the plurality of comparison circuits are provided. OR gates for the output of the circuit comparing the rate of change output from the plurality of resonant circuits to a low threshold and the AND gate for the output of comparing the rate of change output from the plurality of resonant circuits to a high threshold. And an ignition circuit that obtains an ignition command signal for the inflator by selecting the output from the plurality of resonance circuits and the output compared with a predetermined threshold value via an AND gate. The airbag device according to any one of claims 2 and 5.