KR19990069547A - Apparatus and method for sensing and acceleration for airbag ECU - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an air bag apparatus for a vehicle, and more particularly, to an air bag apparatus for a vehicle, which comprises a sensing and acceleration sensing device 50 for detecting a collision upon a collision of the vehicle, An analog-to-digital converter 70 for converting an analog signal output from the collision to a digital signal, and a parallel signal converted from a digital signal into an analog signal by the analog- A parallel / serial converter 80 for converting the digital serial signal into a serial signal and a microcomputer MICOM 80 for receiving the digital serial signal output from the parallel / 90), so that it is possible to operate the airbag ECU timely at a low price, and even when measuring the acceleration value, the acceleration value is obtained using the measuring sensor having a large measuring force The following can be predicted by monitoring the acceleration and the acceleration sensed by the first to fourth Hall sensors at regular intervals, .

Description

Apparatus and method for sensing and acceleration for airbag ECU

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air bag apparatus for a vehicle, and more particularly, an air bag ECU (electronic control unit) operated by an electronic signal is integrated with a mechanical device so as not to cause a malfunction due to an electric field and an electromagnetic interference And an apparatus and method for sensing acceleration and acceleration for an airbag ECU.

Conventionally, an airbag control device includes a safing sensor controlled by a mechanical operation, and an acceleration sensor that detects an impact amount at the time of a vehicle collision as an acceleration value due to vibration of a mass and converts mechanical motion into an electrical signal .

And Newton's equation of motion applied to the acceleration sensor

Lt; / RTI >

k is a spring constant, m is a mass constant, and c is a damping constant.

When the metal body receives a force in the longitudinal direction in the piezo resistor (R), the acceleration sensor is deformed by? X,

Lt; / RTI &

At that time, the sectional area becomes smaller by? S, so that the deformation due to external impact

.

here, e ₀ Is a constant according to the metal material.

As shown in FIG. 1, the shifting sensor includes a reed switch 20, which is switched on when the vehicle senses a collision, and a reed switch 20 installed on both sides of the reed switch 20 A spring 60 disposed on the outer side of the reed switch 20 for applying an elastic force to the reed switch 20 and a spring 60 mounted on the reed switch 20 to move the reed switch 20 to the left An upper magnet 40 and a lower magnet 42 for turning on the reed switch 20 by a magnetic field.

Therefore, when a collision occurs while the vehicle is running, the upper magnet 40 and the lower magnet 42 attached to the upper and lower portions of the support portion 30 are moved to the left due to the amount of the impact of the vehicle. At this time, When the impact is generated, the reed switch 20 is turned on by the magnetic field generated in the upper magnet 40 and the lower magnet 42, as shown in FIG. 1 (B).

As described above, the above-described cleaning sensor has a problem that the airbag ECU of the vehicle is controlled so as not to malfunction due to electric or electronic errors, but an acceleration sensor must be separately provided.

In addition, the acceleration sensor is expensive and the acceleration value measured by the fine mass is accurate in the high frequency range, but the movement of the person who is actually in the vehicle is operated in a low frequency range where the scalpel is large and the speed is low Therefore, there is a problem in that the airbag ECU can not accurately predict the situation, and furthermore, only the on / off for the airbag operation is informed.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems and provide an apparatus and method for an airbag ECU capable of minimizing errors due to electrical and electronic errors, And an acceleration sensing device and method.

According to another aspect of the present invention, there is provided an apparatus for detecting and detecting an airbag ECU, the apparatus comprising: a sensing and acceleration sensing device for sensing a collision when the vehicle collides with the vehicle and turning on the sensing device; An analog-to-digital converter for converting an analog signal output from a collision of the vehicle into a digital signal; a serial / parallel converter for converting a parallel signal converted from an analog signal into a digital signal in the analog- And a microcomputer (MICOM) for receiving a digital serial signal output from the parallel / serial converter and controlling the entire system.

According to another aspect of the present invention, there is provided a method for detecting an acceleration and an acceleration for an airbag ECU, the method including: a first step of clearing an initial value of a microcomputer; (S2) in which the contacts of the first switch unit and the second switch of the reed switch are turned on by a magnetic field generated in the upper magnet and the lower magnet when the vehicle collides after being cleared, It is determined whether or not the first to fourth hall sensors set in the first most significant bit are present, and the first through fourth hall sensors set to 1 in the most significant first bit are determined If there is no hall sensor, it is determined in step S3 that the next step is performed, and in step S3, it is determined whether there is a signal in which the next bit is high, that is, 1 < / RTI > (S4) to 10 (S10) in which the next step is continuously performed when the 4-hole sensor is not present, and the first to fourth holes And if the sensor is present, setting the flag to 1 (S11).

Figs. 1 (A) and 1 (B) are schematic views showing the operating state of a conventional airbag control device,

Fig. 2 is a circuit diagram of a shaking and acceleration sensing device for an airbag ECU according to the present invention,

3 (a) and 3 (b) are graphs showing the distribution of magnetic flux density at the time of operation of the Hall sensor and magnet according to the present invention,

4 is a schematic view showing a configuration of a shaking and acceleration sensing apparatus according to the present invention,

5 (a) and 5 (b) are schematic diagrams showing states of 8 bits for each hall sensor input to a microcomputer after a magnetic field is applied to the Hall sensor of the present invention.

Description of the Related Art

10: Support part 20: Reed switch

30: Support portion 40, 42: Upper and lower magnet

50: Seepage and acceleration sensor

52, 54, 56, 58: first, second, third and fourth Hall sensors

60: spring 70: analog / digital converter

72, 74, 76, 78: first, second, third and fourth analog-to-digital converters

80: Parallel / serial converter 90: Microcomputer

201: first switch 203: second switch

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following will describe the present invention with reference to the accompanying drawings.

As shown in FIG. 2, the present invention is characterized in that the vehicle includes a driving force sensor 50 for sensing an impact amount when a vehicle is in a collision, an analog An analog to digital converter 70 for converting an analogue signal into a digital signal and a parallel signal converted from a digital signal into an analog signal by the analog to digital converter 70 into a serial signal And a microcomputer (MICOM) 90 for receiving the digital serial signal output from the parallel / serial converter 80 and controlling the entire system, have.

4, the safing and acceleration device 50 includes a reed switch 20 that is switched while the vehicle is being moved by an impact amount in the event of a collision and a reed switch 20 that is connected to both sides of the reed switch 20 And a switch unit 20 installed on the support unit 30 to generate a magnetic field when the reed switch 20 is moved by a collision of the vehicle so that switching of the reed switch 20 is turned on An upper magnet 40 disposed below the supporter 30 to switch the reed switch 20 on so as to generate a magnetic field when the vehicle is collided with the reed switch 20, The upper magnet 40 is sensed by the influence of the magnetic field generated in the upper magnet 40 when the upper magnet 40 moves due to the collision of the vehicle in the event of a vehicle collision, It is composed of first to fourth Hall sensor (52, 54, 56, 58), and a spring 60 which is arranged at the outer side of the reed switch 20 applies a resilient force to detect the distance.

The reed switch 20 includes a first switch 201 connected to the support portion 10 and a second switch 20 connected to the support portion 30 so as to be moved by an amount of impact together with the support portion 30, And a switch 203.

The analog-to-digital converter 70 includes a first analog-to-digital converter 78 connected to the first Hall sensor 52 to convert an analog signal into a digital signal, A second analog-to-digital converter 76 connected to the third Hall sensor 56 for converting an analog signal into a digital signal, a third analog-to-digital converter And a fourth analog-to-digital converter 72 connected to the fourth Hall sensor 58 for converting an analog signal into a digital signal.

The resistor R1, resistor R2, resistor R3, resistor R4 and resistor R5 are resistances for stabilizing the circuit.

The operation and operation of the apparatus and method for detecting and detecting an airbag ECU according to the present invention will now be described with reference to the accompanying drawings.

A first step S1 of clearing the initial value of the microcomputer 90 to set an initial value of the microcomputer 90 and a second step S1 of clearing the initial value of the microcomputer 90 by the first step S1, When the vehicle collides with the vehicle, the upper magnet 40 and the lower magnet 42 mounted on the vehicle are moved in the left direction by the amount of the impact.

When the upper magnet 40 and the lower magnet 42 are moved in the left direction according to the amount of the impact, for example, a plurality of the magnets 40 are installed on the lower side of the sensing and acceleration sensing device 50, Hole sensor 52. When the upper magnet 40 and the lower magnet 42 come to a certain distance, the magnetic field generated by the upper magnet 40 and the lower magnet 42 causes the lead (S2) in which the contacts of the first switch (201) and the second switch (203) of the switch (20) are turned on and the second step 5, when there is any one of the first through fourth hall sensors 52, 54, 56, 58 set to the first most significant bit The flag of the first through fourth hall sensors 52, 54, 56, 58 set to 1 is set to 1 If there is no first through fourth hall sensors 52, 54, 56, 58 set to 1 in the most significant first bit, the next step S3 is performed, Lt; / RTI >

In step S3, if it is detected that each bit of the first through fourth hall sensors 52, 54, 56, 58 is high and there is a signal applied in a high level, Likewise, when the upper magnet 40 and the lower magnet 42 are moved by the impact amount of the vehicle to approach any of the first through fourth hall sensors 52, 54, 56, 58, For example, if the fourth Hall sensor 52, 54, 56, 58 is closest to the third Hall sensor 56, the distribution of the magnetic flux density is the largest at the third Hall sensor 56 that is closest.

When the analog signal due to the distribution of magnetic flux density is converted into a digital signal by the analog-to-digital converter 70 and then applied to the parallel / serial converter 80, the parallel / 70, and converts the parallel signal into a serial signal, and then applies the parallel signal to the microcomputer 90.

Then, the microcomputer 90 calculates the acceleration a by the force of the Hall effect acting on the first through fourth hall sensors 52, 54, 56 and 58,

Where F is

Since F = -IOWB * dL,

The current I is obtained from the magnetic flux density B of the magnetic field acting on the first to fourth Hall sensors 52, 54, 56 and 58, and a plurality of Hall sensors 52, 54, 56 and 58 Since the largest magnetic flux density acts in any one of them, it is possible to calculate F by detecting the movement distance L and obtaining the moving distance L.

Therefore, the force calculated from the magnetic flux density, the current and the distance is finally F = ma, so that the acceleration value a of the vehicle can be easily calculated.

As described above, the microcomputer 90 calculates the acceleration value according to the amount of impact of the vehicle when the vehicle collides.

If the first through fourth hall sensors 52, 54, 56 and 58 are set to 1 in the second most significant bit after performing the third step S3, the first through fourth When the flags of the Hall sensors 52, 54, 56, 58 are set to 1 and there are no first to fourth hall sensors 52, 54, 56, 58 set to 1 in the second most significant bit, (S4), and after the fourth step (S4), it is determined whether there is a signal in which the next bit is high, that is, 1 is repeated, as described above. Thereafter, The first to fourth hall sensors 52, 54, 56 and 58 set to 1 are set to 1 and set to 1 when there are four to four Hall sensors 52, 54, 56, If there is no first to fourth hall sensors 52, 54, 56 and 58, then it is constituted of five steps (S5) to step S10 (S10) to continue the next step.

That is, as described above, after the signals detected by the first through fourth Hall sensors 52, 54, 56, and 58 are converted into digital signals, one of the eight most significant bits And the above operation is continued to calculate the acceleration value at the time of the collision of the vehicle so that the airbag ECU operates appropriately in accordance with the amount of the impact of the vehicle to control the airbag to operate in a timely manner.

In order to simplify the description of the sensors of the first to fourth Hall sensors 52, 54, 56 and 58, only four sensors are shown and only four analog sensors 70 are shown. However, It is also possible to use a plurality of first through fourth Hall sensors and an analog / digital converter not shown in the present invention.

The apparatus and method for detecting and detecting an airbag ECU for an airbag according to the present invention as described above are characterized in that the first to fourth hall sensors are combined with the reed switch to integrally form the functions of the acceleration measuring function and the mechanical clearing sensor , The airbag ECU can be operated in a timely manner at a low price, and even when the acceleration value is measured, the acceleration value is obtained by using a large-sized shaking sensor, so that the acceleration value can be measured almost similar to the actual acceleration value The following matters can be predicted by monitoring the first to fourth hall sensors at every cycle whether or not the shaking and acceleration sensing apparatus normally operates.

Claims (4)

An acceleration / deceleration sensor for detecting a collision when the vehicle is in a collision, an analog / digital converter for converting an analog signal output from the acceleration / deceleration sensor into a digital signal, A parallel / serial converter for converting a parallel signal converted from a digital signal into an analog signal in the analog / digital converter into a serial signal; and a parallel / And a microcomputer (MICOM) for receiving the digital serial signal and controlling the entire system. 2. The vehicle steering apparatus according to claim 1, wherein the safing device and the acceleration device include a reed switch that is switched while being moved by an impact amount when the vehicle is collided, a support portion that is connected to both sides of the reed switch, A lower magnet for generating a magnetic field when the reed switch is moved by a collision of the vehicle to cause switching of the reed switch to be turned on and switching the reed switch to be turned on by generating a magnetic field, A plurality of upper and lower magnets are installed at regular intervals below the reed switch to sense the movement distance when the upper magnet is moved due to collision of the vehicle when the vehicle collides with the upper magnet due to a magnetic field generated in the upper magnet, The first through fourth Hall sensors, and the outer side of the reed switch And a spring for applying an elastic force to the airbag. [2] The apparatus of claim 1, wherein the analog-to-digital converter comprises: a first analog-to-digital converter connected to the first Hall sensor to convert an analog signal into a digital signal; A third analog-to-digital converter connected to the third hall sensor for converting an analog signal into a digital signal, and a third analog-to-digital converter connected to the fourth hall sensor for converting the analog signal into a digital signal, And a fourth analog-to-digital converter for converting the signal into a signal. (S1) of clearing the initial value of the microcomputer and a magnetic field generated in the upper magnet and the lower magnet when the vehicle collides after the initial value is cleared by the first step (S1) (S2) in which the contacts of the first switch unit and the second switch of the first switch unit are turned on; and when the shifting and acceleration sensing apparatus is turned on in the second step S2, If there is no first to fourth Hall sensors and if there is no first to fourth Hall sensors set to 1 in the first most significant bit, then the following step is performed (S3); and the third step S3). Thereafter, it is repeatedly determined whether there is a signal having a high level, that is, 1 is applied to the next bit. If there is no first through fourth hall sensors set to 1, the next step is continued (S4) through 10 (S10) When the first to fourth hall sensors are set to 1 in step S3 to step S10, the flag is set to 1 in step 11 (S11). ≪ / RTI >