JPH09175321A - Actuating device for occupant restraining device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make accurate judgement for the operation of an occupant restraining device even when such an acceleration sensor is used that the sensitivity error originating from the manufacture is relatively large. SOLUTION: To make calibration of an acceleration sensor 11, a prescribed acceleration is given, and the acceleration sensing signal Vts given at this time by the sensor is held in a test value holding part 15. In practical application, a correction factor calculating part 17 calculates as a correction factor (k), the ratio of the reference value Vtsref of the acceleration sensing signal, which should be given by an ideal acceleration sensor, to the test value Vts, and a practical threshold setting part 18 calculates the practical threshold k.THref for judging the operation by multiplying the ideal threshold THref for judging the operation by the correction factor (k). The integral value Vs obtained by subjecting the acceleration sensing signal V to time integration using an integrator 13 is compared by a comparator 14 with the practical threshold k.THref, and if the integral Vs is greater, an actuate command for the occupant restraining device is issued.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an actuating device for an occupant restraint system.

[0002]

2. Description of the Related Art Generally, an occupant restraint device such as an SRS airbag installed in an automobile to protect the safety of an occupant in the event of an automobile collision detects an impact at the time of an impact with an acceleration sensor to detect a predetermined impact. This is a system that is activated when an acceleration that exceeds a threshold value (actually, deceleration that exceeds a certain threshold value) is detected.

As an acceleration sensor used for such an occupant restraint system actuating device, one having an actuation diagnosis function has been conventionally used and has a circuit configuration shown in FIG. That is, the acceleration sensor 1 that outputs a voltage signal according to the magnitude of the acceleration applied to the automobile by an external force (which is a magnitude deceleration at the time of a collision, but will be described as acceleration here), and the voltage output by the acceleration sensor 1 An A / D converter 2 for A / D converting the signal and taking it in;
The integrator 3 that repeatedly integrates the voltage signal V taken in by the A / D converter 2 for a constant period Δt, the restraint device operation determination threshold THref registered in advance in the memory 4, and the integration from the integrator 3. It is composed of a comparator 5 which compares the value Vs and outputs an operation command (ignition signal for an airbag) S of the restraint system when the integrated value Vs becomes larger. Practically, the portion inside the encircled line A in FIG. 5 is incorporated in the microcomputer and executed by program processing.

[0004]

SUMMARY OF THE INVENTION The conventional actuating device for an occupant restraint system has the following problems.
The acceleration sensor 1 used in the actuating device of the occupant restraint system is an extremely small element, and is manufactured using semiconductor manufacturing technology. However, since individual differences occur in manufacturing, it is tested whether it can be put to practical use. It is necessary, and even if it passes the test, further calibration is required.

In the above test, a predetermined acceleration is externally applied to each acceleration sensor, the acceleration detection signal output from the acceleration sensor is compared with a test reference value, and an error of several percent is detected with respect to the test reference value. If it is within the range, it is regarded as acceptable, and if there is an error exceeding it, it is discarded as a defective product. Further, since the accelerometers that pass also have individual differences, the restraint device operation determination threshold value TH registered in the memory 4 is set.
Calibration work is required to correct ref according to the above error.

Therefore, in the conventional occupant restraint system actuating device, the yield of the acceleration sensor used for the occupant restraining device is low, and a large amount of labor is required for the calibration work, resulting in a problem of increased cost.

The present invention has been made in view of such conventional problems, and even if an acceleration sensor having a relatively large error with respect to an ideal acceleration sensor is used, the occupant restraint system does not lose reliability. Can be operated, and as a result, even an acceleration sensor with a relatively large error relative to the ideal acceleration sensor can be put to practical use, and the labor of calibration work is also small, which reduces the cost. It is an object of the present invention to provide an occupant restraint system actuating device capable of achieving the above.

[0008]

An actuating device for an occupant restraint system according to a first aspect of the present invention is an acceleration sensor with an actuation diagnosis function having a characteristic of receiving an external acceleration and outputting an electric signal corresponding to the magnitude of the external acceleration. A test value holding unit that holds an acceleration detection signal output when the acceleration sensor receives a constant reference test acceleration in a calibration test; and the acceleration detection signal and the reference acceleration held by the test value holding unit. The acceleration coefficient and the reference value of the acceleration detection signal that should be output by the ideal acceleration sensor of the same specifications as the correction coefficient calculation unit that outputs as a correction coefficient and the ideal threshold value for restraint device operation determination A practical threshold value setting unit that multiplies the correction coefficient to set a practical threshold value for determining the operation of the restraint device, and an acceleration detection signal corresponding to the acceleration output by the acceleration sensor. And an integrated value of the integrator are compared with a practical threshold value set by the practical threshold value setting unit, and when the integral value is larger, an operation command for the occupant restraint system is output. And a comparator that does this.

In the operating device for an occupant restraint system according to the present invention, a predetermined acceleration is applied to the acceleration sensor from the outside when the acceleration sensor is calibrated, and the acceleration detection signal output from the acceleration sensor at that time is held as a test value. Keep it in the section.

In practical use, in the correction coefficient calculation unit, the ratio between the reference value of the acceleration detection signal output by the ideal acceleration sensor having the same specifications and the acceleration detection signal held by the test value holding unit is used as the correction coefficient. Then, the practical threshold value setting section multiplies the ideal threshold value for restraint device actuation determination by the correction coefficient to calculate the practical threshold value for restraint device actuation determination. Then, the acceleration detection signal corresponding to the acceleration output from the acceleration sensor is time-integrated by the integrator and the integrated value is compared with the practical threshold value by the comparator, and when the integrated value is larger, the operation command of the occupant restraint system is issued. Is output.

Therefore, according to the actuating device of the occupant restraint system, an acceleration sensor having a sensitivity error within a predetermined range is not used as a practical acceleration sensor, but individual acceleration sensors that are different from each other in manufacturing are used. Regarding the above, in the calibration test, the sensitivity correction coefficient is calculated in advance by comparing with the signal that should be output from the ideal acceleration sensor, and in practical use, the correction coefficient reflecting the characteristics of each acceleration sensor is used. Since the threshold value for operation determination is changed, it is not necessary to keep the manufacturing individual difference within a range of several percent, which is conventionally required as a practical acceleration sensor, and the acceleration sensor with a larger individual difference. However, it can be put to practical use, and the yield can be improved accordingly.

Further, the setting work of the threshold does not need to be finely adjusted for each acceleration sensor based on the measurement value at the time of the calibration test, and it is automatically performed by adding a predetermined acceleration to the acceleration sensor at the time of the calibration test. In addition, the threshold value corresponding to the sensitivity characteristic of the acceleration sensor can be automatically set, and the labor required for setting the threshold value can be reduced.

According to a second aspect of the present invention, there is provided an actuating device for an occupant restraint system, wherein the acceleration sensor has an actuation diagnosis function and has a characteristic of receiving an external acceleration and outputting an electric signal corresponding to the magnitude of the external acceleration. A test value holding unit that holds an acceleration detection signal output when a constant reference test acceleration is received in a calibration test, the acceleration detection signal held by the test value holding unit, and the acceleration sensor with respect to the reference acceleration. And a standard acceleration detection signal that should be output by an ideal acceleration sensor of the same specification as above, and a correction coefficient calculation unit that outputs as a correction coefficient and an acceleration detection signal corresponding to the acceleration output by the acceleration sensor are time-integrated. An integrator, a calibrator that performs a correction by dividing the integrated value of the integrator by the correction coefficient, and the integral corrected by the calibrator The integral value is compared with the ideal threshold for determining restraining device actuated, in which a comparator which outputs the operation command of the occupant restraint device when towards the integral value after the correction is large.

In the occupant restraint system actuating device according to the present invention, a predetermined acceleration is applied to the acceleration sensor from the outside when the acceleration sensor is calibrated, and the acceleration detection signal output from the acceleration sensor at that time is held as a test value. Keep it in the section.

In practical use, the correction coefficient calculation unit calculates the ratio of the reference value of the acceleration detection signal output by the ideal acceleration sensor having the same specifications and the acceleration detection signal held by the test value holding unit. Then, the integrated value obtained by time-integrating the acceleration detection signal corresponding to the acceleration output by the acceleration sensor by the integrator is corrected by the correction coefficient in the calibrator and then output to the comparator. Then, the comparator compares the ideal threshold value for determining the restraint system operation with the corrected integrated value, and outputs an operation command for the occupant restraint system when the integrated value is larger.

Therefore, according to this occupant restraint system actuating device, as in the case of the first aspect of the invention, a practical acceleration sensor whose sensitivity error is within a predetermined range is not used, but is manufactured. Even an acceleration sensor having a relatively large individual difference can be put to practical use, and the yield can be improved accordingly.

Further, as the threshold value, a threshold value corresponding to an ideal acceleration sensor is used, and the integrated value of the acceleration detection signal of the practical acceleration sensor is made to coincide with that of the ideal acceleration sensor. Since the calibration device is compared with the ideal threshold value after the calibration to determine the operation of the restraint device, the sensitivity of the acceleration sensor can be automatically calibrated by simply applying a predetermined acceleration to the acceleration sensor during the calibration test. The labor required for setting the value can also be reduced.

[0018]

As described above, according to the invention of claim 1,
Rather than using a practical acceleration sensor whose sensitivity error is within the specified range, the signals that should be output by the ideal acceleration sensor in advance during the calibration test for each acceleration sensor that causes individual differences in manufacturing. The sensitivity correction coefficient is calculated in comparison with the above, and in practical use, the acceleration judgment threshold value is changed by using the correction coefficient reflecting the characteristics of each acceleration sensor. As a result, it is not necessary to keep the manufacturing individual difference within a range of several percent, which is conventionally required, and an acceleration sensor with a larger individual difference can be put to practical use, and the yield can be improved accordingly. Also, the threshold setting work does not need to be finely adjusted for each acceleration sensor based on the measured value during the calibration test. It is possible to automatically set the threshold value according to the sensitivity characteristic of the acceleration sensor by adding a predetermined acceleration to the degree sensor, and it is possible to reduce the labor required for setting the threshold value. As a result, the manufacturing cost of the entire device can be significantly reduced.

According to the second aspect of the invention, as in the first aspect of the invention, a practical acceleration sensor whose sensitivity error is within a predetermined range is not used, but an individual difference in manufacturing is caused. Even a relatively large acceleration sensor can be put to practical use, and the yield can be improved accordingly. In addition, a threshold value corresponding to an ideal acceleration sensor is used as the threshold value, and the acceleration detection of a practical acceleration sensor can be used. The integrated value of the signal is calibrated so that it matches that of an ideal acceleration sensor, and then compared with the ideal threshold value to determine the operation of the restraint system, so only a predetermined acceleration is applied to the acceleration sensor during the calibration test. The sensitivity of the accelerometer can be automatically calibrated with, and the labor required to set the threshold value can be reduced, resulting in a significant reduction in the manufacturing cost of the entire device. It is possible.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a circuit configuration of one embodiment of the present invention. The operating device for an occupant restraint system according to this embodiment is an acceleration sensor 11 with an actuation diagnosis function that outputs the same electric signal (here, voltage signal) as when a predetermined acceleration is detected by applying a predetermined voltage. And an A / D converter 12 that performs A / D conversion of the electric signal output from the acceleration sensor 1, and a digital signal V of the acceleration detection signal converted and output from the A / D converter 2 are integrated at fixed time intervals. And an integrated value Vs from the integrator 13 and a practical threshold value k.T.
And a comparator 14 that outputs a restraint device actuation signal S when the integrated value Vs is larger.

Further, at the time of calibration test of the acceleration sensor 11, an acceleration detection signal output from the acceleration sensor 11 by applying a voltage signal corresponding to a test acceleration of a predetermined magnitude, for example, an acceleration of 10 G, is used in the A / D converter 12. A predetermined acceleration detection signal output when a test value holding unit 15 that holds the converted digital signal as a test value Vts and an ideal acceleration sensor having the same specifications as the acceleration sensor 11 receive the same test acceleration. Reference value of
A reference that holds Vtsref and an ideal threshold value THref that is preset as the integral value of the acceleration detection signal detected by the ideal acceleration sensor for a certain period of time that corresponds to the impact that requires the occupant restraint system to operate. A value setting unit 16 is provided. Further, the ratio k (= Vts / Vt) between the test value Vts held in the test value holding unit 15 and the reference value Vtsref of the acceleration detection signal held in the reference value setting unit 16
sref) correction coefficient calculation unit 17 and reference value setting unit 1
6 is used to calculate the practical threshold value k · THref by multiplying the ideal threshold value THref held by 6 with the ratio k obtained by the correction coefficient calculation unit 17, and the practical threshold value setting unit 18 to be given to the comparator 14. I have it.

In practice, the portion inside the encircling line B in FIG. 1 is a portion constituted by a microcomputer. The test value holding unit 15 uses, for example, a P-ROM for each of the practical acceleration sensors 11 at the time of Vts during the configuration test.
Write. Further, the reference value setting unit 16 may be an ordinary ROM, and the reference value Vtsref and the ideal threshold value THref corresponding to the ideal acceleration sensor may be registered.

Next, the operation of the actuating device of the occupant restraint system having the above structure will be described.

<< Calibration Test >> Before putting it into practical use, a calibration test of the acceleration sensor 11 mounted on each occupant restraint system is executed. In this calibration test,
A predetermined voltage signal corresponding to a predetermined acceleration is applied to the acceleration sensor 11, and an acceleration detection signal (usually a voltage value) Vts of the acceleration sensor 11 input through the A / D converter 12 at that time is used as a test value holding unit. Register at 15.

<< In practical use >> When the operating device of the occupant restraint system is mounted on a vehicle and used, an electric signal corresponding to the acceleration acting on the vehicle is input from the acceleration sensor 11 through the A / D converter 12. It

The integrator 13 repeatedly integrates the acceleration detection signal V corresponding to the acceleration input through the A / D converter 12 with a constant time width and gives an integrated value Vs to one input terminal of the comparator 14.

The practical threshold value k.multidot.THref is always given from the practical threshold value setting section 18 to the other input terminal of the comparator 14. This practical threshold value k · THref is based on the following calculation result.

That is, in the correction coefficient calculation unit 17, the test value Vts registered in the test value holding unit 15 during the calibration test and the reference value Vt registered in the reference value setting unit 16 in advance.
The ratio k to sref is calculated and given to the practical threshold setting unit 18, and the practical threshold setting unit 18 uses the reference value setting unit 1
6 is multiplied by the ideal threshold value THref held by 6 and the ratio k obtained by the correction coefficient calculation unit 17 to calculate a practical threshold value k · THref, which is constantly given to the comparator 14. .

This practical threshold value k.THref is not exceeded by the integral value of the acceleration generated during the normal running of the vehicle on which the vehicle is traveling, and if it is the integral value of the acceleration generated by the rapid deceleration during the vehicle collision, Since it is set to a value exceeding
Now, if the mounted vehicle decelerates rapidly due to a collision or the like, the acceleration sensor 11 outputs a large electric signal corresponding to a large acceleration, and the integrated output Vs of the integrator 13 is compared at the moment when it exceeds the practical threshold value k.THref. The vessel 14 outputs an occupant restraint system actuation signal S, thereby actuating the occupant restraint system and protecting the occupant from the impact during a collision.

As described above, according to the actuating device for the occupant restraint system of this embodiment, the acceleration sensor 11 is applied with an acceleration of a predetermined magnitude during the calibration test.
The acceleration detection signal Vts output by the acceleration sensor is compared with the reference value Vtsref for the ideal acceleration sensor to obtain the correction coefficient k for each characteristic individually for each acceleration sensor, and for the restraint device operation determination for the ideal acceleration sensor. Threshold TH
Practical threshold value k
-THref is also obtained, and this is compared with the integrated value Vs of the acceleration detection signal of the acceleration sensor to determine the operation of the occupant restraint system.

That is, as shown in FIG. 2, in an acceleration sensor in a calibration test, a correction coefficient k = k1 (= Vts / Vt
sref), the practical threshold value k
When THref is used and the integrated value Vs of the output signal of the acceleration sensor during the fixed integration time ts exceeds the practical threshold value k1.THref, the operation command S is output. On the other hand, in another acceleration sensor, if the correction coefficient k = k2 (= Vts / Vtsref), k2 · THref is used as the practical threshold value k · THref, and the acceleration sensor for a certain integration time ts. Integrated value of the output signal of
Even if Vs becomes Vs> k1 · THref or Vs> THref, the operation command S is not output unless it exceeds the practical threshold value k2 · THref.

Therefore, even if a large number of manufactured acceleration sensors have a large individual difference, when they are mounted on the actuator of the occupant restraint system, a correction coefficient corresponding to the characteristics of each acceleration sensor is set during the calibration test. can do.
Therefore, even an acceleration sensor having a relatively large manufacturing error can be put into practical use, and therefore, an acceleration sensor that has been disposed of in the past can be used, and the manufacturing yield of the acceleration sensor can be improved. It can be improved and the cost can be reduced accordingly.

In addition, in the calibration test, the correction coefficient k is automatically calculated and registered on the device side simply by applying a voltage signal corresponding to a predetermined acceleration, so that the work for adjusting the threshold value is simple. Therefore, it is possible to reduce the labor of the engineer in this respect.

Next, another embodiment of the present invention will be described with reference to FIG. The actuation device for an occupant restraint system according to the second embodiment is similar to that of the first embodiment, and is an actuation diagnosis that outputs the same electric signal as when a predetermined acceleration is detected by applying a predetermined voltage. An acceleration sensor 11 with a function, an A / D converter 12 that performs A / D conversion of an electric signal output from the acceleration sensor 1, an integrator 13 that performs time integration at fixed time intervals, and an integration from the integrator 13. The value Vs / k is compared with the ideal threshold THref, and the integrated value Vs
And a comparator 14 that outputs a restraint device actuation signal S when / k is larger.

Further, during the calibration test of the acceleration sensor 11, an acceleration detection signal output by the acceleration sensor 11 by applying a voltage signal corresponding to a test acceleration of a predetermined magnitude, which is a digital signal converted by the A / D converter 12. And a reference value Vtsref of a predetermined acceleration detection signal output when an ideal acceleration sensor having the same specifications as the acceleration sensor 11 receives the same test acceleration. Similarly, a reference value setting unit 16 that holds an ideal threshold value THref for determining the operation of the restraint device for an ideal acceleration sensor is provided. The ideal threshold THre of this reference value setting unit 16
f is connected so as to be directly applied to the comparator 14.

A feature of the second embodiment is that the ratio k (between the test value Vts held in the test value holding unit 15 and the reference value Vtsref of the acceleration detection signal held in the reference value setting unit 16 is = Vts / Vtsref) correction coefficient calculation unit 17
And the correction coefficient k calculated by the correction coefficient calculation unit 17 is A
The acceleration detection signal is calibrated by dividing the acceleration detection signal V from the acceleration sensor 11 output from the / D converter 12, and the calibrated acceleration detection signal V / k is integrator 13
And an acceleration detection signal calibrating unit 19 which is applied to

Even in this embodiment, practically,
In FIG. 3, the portion inside the encircling line C is a portion configured by a microcomputer. And the test value holding unit 1
Vts is written in 5 at the time of a configuration test for each acceleration sensor 11 which is practically used by using a P-ROM. Further, the reference value setting unit 16 may be an ordinary ROM, and the reference value Vtsref and the ideal threshold value THref corresponding to the ideal acceleration sensor may be registered.

Next, the operation of the actuating device of the occupant restraint system having the above structure will be described.

<< Calibration Test >> Similar to the first embodiment, a calibration test of the acceleration sensor 11 mounted on each occupant restraint system is executed before putting it into practical use. In this calibration test, a predetermined voltage signal corresponding to a predetermined acceleration is applied to the acceleration sensor 11, and the acceleration sensor 11 input through the A / D converter 12 at that time is applied.
The acceleration detection signal (normally, voltage value) Vts of is registered in the test value holding unit 15.

<< In Practical Use >> When the operating device of the occupant restraint system is mounted on a vehicle, an electric signal corresponding to the acceleration acting on the vehicle is input from the acceleration sensor 11 through the A / D converter 12. It Then, the digital acceleration detection signal V output from the A / D converter 12 is input to the acceleration detection signal forming unit 19 and is calibrated by dividing by the correction coefficient k from the correction coefficient calculating unit 17 here.
The calibration value V / k of the acceleration detection signal is given to the integrator 13.

The integrator 13 repeatedly time-integrates the calibration value V / k of the acceleration detection signal input from the acceleration signal forming section 19 with a constant time width and outputs the integrated value Vs / k to one input terminal of the comparator 14. give. At the other input terminal of the comparator 14,
The ideal threshold value THref is always given from the reference value setting unit 16.

Therefore, when the mounted vehicle decelerates rapidly due to a collision or the like, the acceleration sensor 11 outputs a large acceleration detection signal V, and the moment the integrated output Vs / k of the integrator 13 exceeds the ideal threshold THref. In addition, the comparator 14 outputs the occupant restraint device actuation signal S, thereby actuating the occupant restraint device and protecting the occupant from the impact at the time of a collision.

As described above, according to the actuating device for the occupant restraint system of the second embodiment, acceleration of a predetermined magnitude is applied to the acceleration sensor 11 during the calibration test, and the acceleration detected by the acceleration sensor 11 is detected. The signal Vts is compared with a reference value Vtsref for an ideal acceleration sensor, and a correction coefficient k (= Vts / Vtsr corresponding to the characteristic of each acceleration sensor is individually obtained.
ef) is obtained, the acceleration detection signal V from the acceleration sensor is calibrated by this correction coefficient k (that is, V / k is obtained), and its time integrated value Vs / k is the ideal threshold for the ideal acceleration sensor. By comparing with the value THref, the operation of the occupant restraint system is judged.

That is, as shown in FIG. 4, the correction coefficient k = k1 '(= Vts /
Vtsref), the operation command S is output if the calibrated integral value Vs / k1 'of the output signal of the acceleration sensor during the constant integration time ts exceeds the ideal threshold value THref. On the other hand, in another acceleration sensor, the correction coefficient k = k2 ′ (=
Vts / Vtsref), the calibrated integral value is Vs /
k2 ′, which is compared with the ideal threshold value THref to determine the operation of the occupant restraint system.

Therefore, even if a large number of manufactured acceleration sensors have a large individual difference, the correction coefficient k corresponding to the characteristics of each acceleration sensor is set at the time of the calibration test when the acceleration sensor is mounted on the operating device of the occupant restraint system. Obtained and this correction coefficient k
Can be used to calibrate the acceleration detection signal of the acceleration sensor and to determine the operation of the occupant restraint system. For this reason,
Accelerometers that have relatively large manufacturing errors can be used, and therefore, even those that were previously discarded can be used, improving the manufacturing yield of accelerometers. The cost can be reduced accordingly.

In addition, in the calibration test, the correction coefficient k is automatically calculated and registered on the device side by simply applying a voltage signal corresponding to a predetermined acceleration, so that the work for adjusting the threshold value is simple. Therefore, it is possible to reduce the labor of the engineer in this respect.

In the second embodiment, the acceleration detection signal calibration section 19 is placed before the integrator 13 instead of the integrator 13.
By providing the output side of the integrator 13, the integral value Vs of the integrator 13 can be calibrated.

[Brief description of the drawings]

FIG. 1 is a functional block diagram according to a first embodiment of the present invention.

FIG. 2 is a graph showing operating characteristics of the above embodiment.

FIG. 3 is a functional block diagram according to a second embodiment of the present invention.

FIG. 4 is a graph showing operating characteristics of the above embodiment.

FIG. 5 is a functional block diagram of a conventional example.

[Explanation of symbols]

 11 Acceleration Sensor 12 A / D Converter 13 Integrator 14 Comparator 15 Test Value Holding Section 16 Reference Value Setting Section 17 Correction Coefficient Calculation Section 18 Practical Threshold Setting Section 19 Acceleration Detection Signal Calibration Section V Acceleration Detection Signal Vs Integrated Value Vts test value Vtsref reference value THref ideal threshold value k correction factor

Claims (2)

[Claims] 1. An acceleration sensor with an actuation diagnosis function, which has a characteristic of receiving an external acceleration and outputting an electric signal corresponding to the magnitude of the external acceleration. When the acceleration sensor receives a constant reference test acceleration in a calibration test. A test value holding unit that holds the output acceleration detection signal, an acceleration detection that should be output by an ideal acceleration sensor having the same specifications as the acceleration sensor for the acceleration detection signal and the reference acceleration held by the test value holding unit A correction coefficient calculator that calculates the ratio to the reference value of the signal and outputs it as a correction coefficient, and sets the practical threshold value for restraint device operation determination by multiplying the ideal threshold value for restraint device operation determination by the correction coefficient. A practical threshold value setting unit, an integrator that time-integrates an acceleration detection signal corresponding to the acceleration output by the acceleration sensor, and an integrated value of the integrator is the practical value. Compared to the practical threshold threshold setting unit sets, actuating device for passenger restraint system comprising a comparator which outputs an operation command of the occupant restraint device when towards the integration value is great. 2. An acceleration sensor with an actuation diagnosis function, which has a characteristic of receiving an external acceleration and outputting an electric signal corresponding to the magnitude of the external acceleration, when the acceleration sensor receives a constant reference test acceleration in a calibration test. A test value holding unit that holds the output acceleration detection signal, an acceleration detection that should be output by an ideal acceleration sensor having the same specifications as the acceleration sensor for the acceleration detection signal and the reference acceleration held by the test value holding unit A correction coefficient calculation unit that obtains a ratio with a reference value of a signal and outputs the correction coefficient, an integrator that time-integrates an acceleration detection signal corresponding to the acceleration output by the acceleration sensor, and an integration value of the integrator A calibrator that performs the correction by dividing by the correction coefficient output by the correction coefficient calculation unit, and an integrated value of the integrated value corrected by the calibrator. Compared to the ideal threshold for determining apparatus operation, the actuator of the occupant restraint system comprising a comparator which outputs an operation command of the occupant restraint device when towards the integral value after the correction is large.