JPH0834312A - On-vehicle air bag system - Google Patents

Abstract

PURPOSE:To prevent the damage of the vehicle bodies of both the preceding vehicle and one's own vehicle as well as the injures to occupants, when a vehicle during traveling collides with the preceding vehicle or an object, by providing air bags which are inflated in the forward direction of the vehicle by the action of an inflator for preventing the damage or injure of the vehicle and occupants. CONSTITUTION:An on-vehicle air bag system is provided with an output processing circuit 7 by which when one's own vehicle is traveling, in the case where it collides with the preceding vehicle or an object, a collision predictive signal is output to an inflator 1 on the basis of the command signal set previously from the judging part 8 of a microcomputer 4; and with an air bag 2 which has been fitted to the lower outside of the front bumper of the vehicle, and also which has been fitted in interlocking with the inflator 1 so as to be inflated by the action of the inflator 1 in the forward direction of the vehicle for preventing the damage or injure to the vehicle or occupants. Thereby, the air bag 2 can be inflated toward the front of the vehicle directly before the collision, and the vehicles each other as well as occupants can be protected from the shock at the time of collision of the vehicle.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle-mounted air bag, and is mounted on the outside of a vehicle to protect not only a passenger but also a vehicle body when the vehicle collides with a preceding vehicle or an object while the vehicle is traveling. The present invention relates to an in-vehicle airbag system.

[0002]

2. Description of the Related Art A conventional air bag for protecting a boarding vehicle is
It is provided inside the vehicle to protect the occupants in the event of a vehicle collision. As shown in FIG. 9, the airbag system is provided with a storage box 20 under a driver's and an assistant's seat, that is, under a passenger's seat, and an electric sensor 21 and a mechanical sensor 22 One mechanical sensor (collision sensor) 23 is arranged in front of the radiator one by one. The storage box 20
In addition to the electric sensor 21 and the mechanical sensor 22, a diagnostic device, a step-up power supply, and a backup capacitor are built in. In the figure, reference numeral 24 is an air bag module in which an air bag, an inflator, a cable reel and the like are housed, and 25 is a warning lamp. That is, in the conventional system, as shown in the circuit block diagram of FIG. 10, electromechanical sensors 26 and 27 (front airbag sensors) are attached to the left and right fenders of the vehicle, respectively. Furthermore, an electric sensor (center airbag sensor) 28 is installed in the floor tunnel.
The electronic circuit unit 30 (the determination unit 31, the diagnostic device 32, and the booster circuit 33) is integrally arranged with the backup capacitor 34. For example, when the host vehicle collides with a preceding vehicle or an object, a signal that the electric sensor 21 detects the impact is output, and the determination value determined by the determination unit 31 is integrated when the determination value is equal to or more than a predetermined value. It is determined whether or not the collision is necessary for deployment, and the ignition device (squib) 38 in the inflator 37 is energized via the transistor 36. On the other hand, the electromechanical sensors 26 and 27 at the front of the vehicle are arranged in parallel with the transistor 36 and are adapted to energize the ignition device 38 via the contacts. The power supply circuit is designed redundantly in consideration of reliability, and in consideration of disconnection of the power supply line due to impact at the time of collision, damage to the battery or insufficient charging, the booster circuit 33 maintains a voltage and a backup capacitor. Electrical energy is stored in the (backup power source) 34. In the event of a vehicle collision, the vehicle must operate reliably, so a diagnostic device (not shown) provided separately diagnoses the states of the backup power source 34 (power circuit), the determination unit 31, the ignition circuit, and the ignition device 38. The diagnostic device itself is also adapted to diagnose. The determination unit 31 determines by a microcomputer. The ignition device 38 ignites the explosive charge by the electric charge charged by the semiconductor switch. It takes about 1 time from the collision to the deployment of the airbag 35.
It is set to 00 milliseconds.

FIG. 11 is an example of an electromechanical sensor and is a structural diagram of a viscous damping type impact sensor. This is a system in which a spherical mass 41 moves in the cylinder 40, and the mass is usually attracted to the right by a right magnet 42. When the mass 41 receives a shock (deceleration), if the deceleration and time are sufficient to overcome the attractive force of the magnet 42 and the viscous force of the air trying to pass through the gap between the cylinder 40 and the mass 41, the mass 41 will be Move to the contact and close the contact.
The impact sensor basically detects acceleration at the time of impact. As a method of detecting the acceleration, a system composed of a spring and a mass is generally used, and the mass is used as a force by the acceleration to generate a displacement against the spring, and a signal output accompanying the displacement is detected. In addition, the conventional impact sensor,
There are those called ES type (electronic type) and EM type (electro-mechanical type). The main methods of the ES type are those that use changes in metal resistance, those that use the piezoresistive effect of a semiconductor, those that use the piezoelectric effect, those that use magnetostriction, those that use electromagnetic induction, those that use electrostatic capacitance, There are those that use a differential transformer and those that use interference fringes of light waves. Further, some EM type impact sensors have a mechanical contact provided on the side of the housing that is fixed so that when a certain acceleration or more occurs, the mass moves to activate the contact and output a switch output. is there.

12A and 12B are structural views of an EM type impact sensor called a safing sensor. In this case, a cylindrical permanent magnet 46 having a predetermined mass has a reed switch 4 by a coil spring 47 with a reed switch 45 whose contacts are opened and closed by magnetism as an axis.
5 off area. For example, FIG.
As shown in FIG. 5, when an acceleration of several G or more, which cannot occur in a sudden braking, acts, the permanent magnet 46 moves against the coil spring 47, and the reed switch 45 is turned on. Since the reed switch 45 can be opened and closed within 1 millisecond and the contact is sealed in an inert gas, the reliability of the contact is good. In addition, a mechanism is used in which the explosive is ignited only when both the ES-type impact sensor and the EM-type impact sensor (safing sensor) operate to prevent malfunction due to electromagnetic noise.

FIG. 13 is a structural diagram of the inflator 37. This is a mechanism in which the igniter 50 operates and the gas generating agent 52 burns via the igniting agent 51. Nitrogen gas is generated by this combustion, and the filter 54 cools and removes residues to inflate the air bag 35. In the figure, reference numeral 53 is a rivet, and the inflator 37 is required to be precise, so that laser beam welding is performed.

[0006]

As described above, when using the conventional vehicle-mounted air bag, the air bag is mounted in the steering wheel in the vehicle interior,
The signal detected by the sensor detects the impact (deceleration) applied to the vehicle at the time of collision, and the nitrogen gas generator (inflator) is electrically ignited to burn the gas generant and generate nitrogen gas to inflate the air bag. It has become. The inflated airbag prevents passengers from colliding with the windshield, steering, and dashboard at the time of a collision. Therefore, the conventional in-vehicle airbag only protects the body of the vehicle such as the driver, and when the following vehicle collides with the preceding vehicle or the traveling vehicle collides with an object, There was a problem that the traveling vehicle would be damaged.

The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to detect not only passengers but also preceding vehicles when the preceding vehicle or an object collides with an object while the vehicle is traveling. (EN) Provided is an in-vehicle air bag that prevents damage to the vehicle body of an own vehicle.

[0008]

In order to achieve the above object, the vehicle-mounted air bag of the present invention as defined in claim 1 has a gear ratio of an engine which shows a braking ability of a vehicle, a force on a foot brake, By the A / D converter for inputting the analog signal such as the initial time of stepping on the foot brake and converting it into the digital signal, and the vehicle speed sensor attached to the vehicle for the distance between the vehicle and other vehicles or other objects An input processing circuit for measuring and inputting as a digital signal, and the above A /
A microcomputer for comparing the digital signal converted by the D converter with the digital signal output from the input processing circuit to calculate the distance between the vehicle or another object and the vehicle, and the microcomputer. A built-in determination unit that compares a signal output from the microcomputer with a signal stored in advance in a storage unit of the microcomputer to determine whether to output a command signal of a collision prediction signal, and the determination unit An output processing circuit that outputs a collision prediction signal to the inflator based on a command signal from the determination unit when it is determined to collide, and is attached to the lower outer portion of the front bumper of the vehicle and is linked to the inflator. It is installed and inflates in the forward direction of the vehicle due to the operation of the inflator, which may damage the vehicle or the driver. And wherein the air bag to stop, that it was formed from.

[0009]

According to the present invention having the above-mentioned structure, when the driving vehicle collides with a preceding vehicle or an object while the vehicle is traveling, a command from the determination unit of the microcomputer is given in advance. The output processing circuit that outputs a collision prediction signal to the inflator based on the signal and the lower outer portion of the front bumper of the vehicle are mounted and are connected to the inflator in a forward direction of the vehicle by the operation of the inflator. Since it is equipped with an airbag that inflates to prevent damage to the vehicle and the driver, it is possible to inflate the airbag to the front of the vehicle immediately before the collision, and boarding from the impact at the time of the collision of the vehicle. Not only the person but also the vehicles can be protected.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an exterior air bag system according to the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing the appearance of an in-vehicle air bag system of the present invention, FIG. 2 is a circuit block diagram showing a basic circuit configuration of the in-vehicle air bag system of the present invention, and FIG. 3 is a laser radar type inter-vehicle distance measurement. FIG. 4 is an explanatory view showing the principle, FIG. 4 is a block diagram of a distance measuring circuit used for laser radar type inter-vehicle distance measurement, FIG. 5 (1-a) to (3) are characteristic diagrams showing waveforms of respective parts, and FIG. FIG. 7 is a cross-sectional view showing an arrangement of a vehicle speed sensor used in the invention, FIG. 7 is a circuit diagram showing a circuit configuration of an MRE used in the present invention, and FIGS. 8A to 8D are explanatory diagrams showing an operating principle of the MRE. .

As shown in FIG. 1, the inflator 1 used in the vehicle-mounted air bag system according to the present invention is attached near the lower part of the bumper outside the own vehicle A, and the inflator 1 is activated by a collision prediction signal. The system is configured to operate and inflate the airbag 2 in front of the own vehicle A to prevent impact on the own vehicle A, other vehicles, and a human body at the time of a collision.

FIG. 2 is a block diagram of the vehicle-mounted air bag system of the present invention. As shown in the figure, the operation control of the airbag system is performed by the ECU 3 (Electron).
icControl Unit), which is a central component. The ECU 3 is roughly configured by a microcomputer 4, an A / D converter 5, an input processing circuit 6, an output processing circuit 7, a determination unit 8 (included in the microcomputer 4), and a power supply circuit 9.

The collision prediction itself is performed based on the control capability, the inter-vehicle distance, and the own vehicle speed. Further, analog signals such as the engine gear ratio, the force on the foot brake, and the initial time when the foot brake is pressed are input to the microcomputer 4 via the A / D converter 5 as control capabilities. As the inter-vehicle distance, the distance between another automobile B or an object and its own automobile A is measured by the method described later, and is input to the microcomputer 4 via the input processing circuit 6.

As the speed of the automobile A, a signal from a vehicle speed sensor, which will be described later, is input to the microcomputer 4 via the input processing circuit 6. The microcomputer 4 performs the following calculation according to the input signal. 1) Calculate the braking ability by engine braking from the gear ratio. 2) Calculate the time and distance from the force on the footbrake to the stop of your car A (your car A
Including the vehicle speed). 3) Calculate the total braking ability according to 1) and 2). 4) Depending on the inter-vehicle distance signal, the inter-vehicle distance elasticity (m /
Calculate c). The acceleration (deceleration) of the inter-vehicle distance that changes momentarily with the vehicle speed signal of the own vehicle A is calculated. In addition, how long the inter-vehicle distance will be within the time until braking calculated by the above 2), the inter-vehicle distance elasticity (m
/ C).

The information obtained by the microcomputer 4 includes the following. Vehicle braking capacity (engine braking according to the gear ratio of the mission, initial time when the foot brake is stepped on, time until own vehicle A stops due to the foot brake, distance) Current inter-vehicle distance (m) Inter-vehicle distance expansion and contraction (m / S)

The PROM 10 used as a storage means in the microcomputer 4 is programmed with the following as judgment information. In the PROM 10 of the microcomputer 4, the relationship between the braking ability and the inter-vehicle distance expansion / contraction degree is programmed in advance and stored as a memory. In other words, it is stored in memory how long the inter-vehicle distance will be before the own car A stops.

The judgment of the judgment unit 7 in the microcomputer 4 is as follows. The determination unit 8 shown in FIG. 4 is built in the microcomputer 4. The determination unit 8 provides the information obtained by the microcomputer 4 and the braking ability of the own vehicle A (the own vehicle A
The time until the vehicle stops, distance), the current inter-vehicle distance, and the inter-vehicle distance expansion / contraction degree, the PROM10 of the microcomputer 4
Information, the braking ability, and the relationship between the inter-vehicle distance expansion and contraction.
By comparing the information of the both, if the inter-vehicle distance when the vehicle is stopped by braking is from zero to minus with respect to the braking distance, it is instructed to send a collision signal to the output processing circuit. The inflator 1 is activated by this signal, and the air bag 2 is set to inflate in the front direction of the automobile A.

Two inflators 1 are attached to the left and right of the lower part of the bumper of the automobile A of its own. Since the air bag 2 for protecting the own vehicle A is much larger than the indoor air bag described in the conventional example, it is naturally necessary to use a large amount of gas. Therefore, the inflator 1 itself is larger than that described in the conventional example.

The air bag 2 is required to have strength enough to withstand the impact of another automobile B or an object because the air bag 2 collides with it. Furthermore, the material of the air bag 2 must also be sufficiently resistant to collision.

Next, an inter-vehicle distance measuring method for measuring the inter-vehicle distance will be described with reference to FIGS. 3 to 5 (1), (2) and (3). FIG. 3 is a principle diagram of inter-vehicle distance measurement by the laser radar method. In this case, the laser radar 15 outputs the pulsed laser light from the pulsed laser driver to another vehicle B.
The vehicle-to-vehicle distance is measured by the mathematical expression (1) by irradiating the (detection object) and detecting the time difference between the irradiation and the return.

FIG. 4 is a circuit block diagram for inter-vehicle distance measurement by the laser radar system. The illumination optical system 16 and the reflection optical system 17 are roughly configured to input the inter-vehicle distance information to the microcomputer 4. In the figure, reference numeral 16a denotes a pulsed light amplifier, which irradiates the pulsed laser light from the pulsed laser driver 19 to another detected object through the irradiation light trigger generation module 16b and the control unit 18, and the reflection optical system 17 reflects the reflected light from the detected object. The light is input to the control unit 18 via the pulsed light amplifier 17a and the reflected light trigger generation module 17b. FIG. 5 shows the characteristics of each of the above parts. FIG. 5 (1) is a characteristic diagram of a pulsed optical amplifier, FIG. 5 (2) is a characteristic diagram of a trigger generation module,
FIG. 5C is a characteristic diagram of time / voltage conversion. 6 to 8 show the structure and principle of the vehicle speed sensor S and the principle of MRE. As shown in FIG. 6, the wire harness 12 above the drive shaft 11 in the automobile A is installed in the middle. The IC 13 is attached to the position. In this case, a magnetic resistance element (MRE; Magnetic Resistance) is used as the vehicle speed sensor S.
An IC 13 with a built-in element 14 is used. When the drive shaft 11 of the automobile A is driven by the gear of the transmission 15 as shown in FIG. 8, the ring multipole magnet 15a connected to this rotates. Due to the change in magnetic flux generated by the rotation of the ring multipole magnet 15a, the resistance of the MRE in the IC 13 changes.

FIGS. 8B to 8D are operation principle diagrams of the vehicle speed sensor circuit of the vehicle speed sensor S using the MRE 14. As shown here, the MRE 14 has a property that the resistance becomes maximum when the direction of the flowing current and the direction of the magnetic force lines are parallel to each other, and conversely, the resistance becomes minimum when the directions of the current and the magnetic force lines are orthogonal to each other. have.

According to the in-vehicle air bag system of the present invention having the above-described structure, when the own vehicle A that is driving collides with the preceding vehicle B or an object while the vehicle is running, a microcomputer is used in advance. The output processing circuit 7 that outputs a collision prediction signal to the inflator 1 based on the command signal from the determination unit 8 of No. 4 and the lower outside portion of the front bumper of the own vehicle A are connected to the inflator 1. And an air bag 2 that is installed by being inflated in the forward direction of its own vehicle A by the operation of the inflator 1 to prevent the vehicle A from being damaged and the driver from being injured. The airbag 2 can be inflated to the front of the vehicle immediately before the collision, so that not only the passengers but also their own vehicle A and Also it becomes possible to protect the damage of the vehicle between the other side of the motor vehicle B.

[0024]

According to the present invention consists of the above configuration, according to the present invention "claim 1", when the own vehicles at the wheel collides with the preceding vehicle or an object while traveling, previously determined in the microcomputer The output processing circuit that outputs a collision prediction signal to the inflator based on the command signal from the vehicle and the lower outer portion of the front bumper of the vehicle, and is attached to the inflator in a linked manner to operate the inflator. Since an airbag is provided to prevent the vehicle from being damaged and the driver being inflated in the front direction of the vehicle, the airbag can be inflated to the front of the vehicle immediately before the collision, resulting in a collision of the vehicle. Not only passengers but also vehicles can be protected from the impact of time, and various effects are achieved.

[Brief description of drawings]

FIG. 1 is a perspective view showing an appearance of an in-vehicle airbag system of the present invention.

FIG. 2 is a circuit block diagram showing a basic circuit configuration of an in-vehicle airbag system of the present invention.

FIG. 3 is an explanatory diagram showing a laser radar type inter-vehicle distance measuring principle.

FIG. 4 is a block diagram of a distance measurement circuit used for laser radar type inter-vehicle distance measurement.

FIG. 5 (1) is a characteristic diagram showing characteristics of a pulsed optical amplifier. (2) is a characteristic diagram of the trigger generation module.
(3) is a characteristic diagram showing characteristics of irradiation light, reflected light, and voltage output in time / voltage conversion.

FIG. 6 is a sectional view showing an arrangement of a vehicle speed sensor used in the present invention.

FIG. 7 is a circuit diagram showing a circuit configuration of an MRE used in the present invention.

FIG. 8A is an explanatory diagram showing directions of magnetic force lines.
(B) is a principle explanatory diagram of MRE showing an example of a magnetic force line in a horizontal direction. (C) shows an example in the direction orthogonal to the magnetic force lines M
It is a principle explanatory view of RE. (D) is an explanatory view of the principle of the MRE showing an example of the magnetic force lines in the vertical direction.

FIG. 9 is a perspective view showing an example of a conventional air bag system.

FIG. 10 is a circuit block diagram showing a circuit configuration of a conventional air bag system example.

FIG. 11 is a cross-sectional view of a main part of a conventionally used impact sensor.

FIG. 12A is a principle diagram when a conventionally used safety sensor is in a stopped state (OFF).
(B) is a principle diagram when the conventionally used safety sensor is in operation (ON).

FIG. 13 is a perspective view showing a cross section of a main part of a conventionally used inflator.

[Explanation of symbols]

 A ・ ・ ・ Own car B ・ ・ ・ Other car 1 ・ ・ ・ Inflator 2 ・ ・ ・ Air bag 3 ・ ・ ・ ECU 4 ・ ・ ・ Microcomputer 5 ・ ・ ・ A / D converter 6 ・ ・ ・ Input processing Circuit 7 ... Output processing circuit 8 ... Judgment part 9 ... Power supply circuit 10 ... PROM 11 ... Drive shaft 12 ... Wire harness 13 ... IC 14 ... Magnetoresistive element ( MRE) 15a ... Ring multi-pole magnet

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[Procedure amendment]

[Submission date] December 7, 1994

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Correction target item name] All drawings

[Correction method] Change

[Correction content]

FIG.

[Figure 3]

[Fig. 2]

[Figure 6]

[Figure 7]

[Figure 9]

FIG. 11

[Fig. 13]

[Figure 4]

[Figure 5]

[Figure 8]

[Fig. 12]

[Figure 10]

Claims (1)

[Claims] Claim: What is claimed is: 1. An engine gear ratio indicating a braking ability of a vehicle,
An A / D converter for inputting an analog signal such as the force on the foot brake, the initial time when the foot brake is pressed, etc., and converting it to a digital signal, and the distance between the host vehicle and another vehicle or another object A vehicle or other object by comparing an input processing circuit that is measured by a vehicle speed sensor attached to the vehicle and input as a digital signal with the digital signal converted by the A / D converter and the digital signal output by the input processing circuit. A microcomputer for calculating the distance between the vehicle and the host vehicle, and a collision prediction by comparing the signal output from the microcomputer built into the microcomputer with the signal previously stored in the storage means of the microcomputer. When the determination unit that determines whether to output the command signal of the signal and the determination unit determines that a collision occurs The output processing circuit that outputs a collision prediction signal to the inflator based on the command signal from the determination unit, and is mounted on the lower outer portion of the front bumper of the vehicle and is connected to the inflator and is connected to the inflator. The in-vehicle airbag system comprises an airbag that is inflated in the front direction of the vehicle when actuated to prevent vehicle damage and the driver.