JP2002096708A - Starting control device for occupant crash protection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To start an occupant crash protection device at timing in accordance with a degree of collision caused on a vehicle concerning a starting control device for the occupant crash protection device. SOLUTION: A floor sensor is provided at a car body central part and a satelite sensor is provided at a car body front part respectively. Computed values V10 and Vn1 are found by applying specified processing on deceleration GF detected in accordance with an output signal of the floor sensor. Additionally, a computed value Vn2 is found by applying specified processing on deceleration GS detected in accordance with an output signal of the satelite sensor. A map in accordance with a collisional level is selected and set as a threshold value changing pattern to start an air bag device. Thereafter, a driving signal is supplied to a driving circuit of the air bag device so that an air bag expands and develops in the case when the computed value V10 exceeds a threshold value SH at the computed value Vn1 on the threshold value changing pattern.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an activation control device for an occupant protection device, and more particularly to an activation of an occupant protection device suitable for activating an occupant protection device for protecting an occupant when a vehicle collides. It relates to a control device.

[0002]

2. Description of the Related Art Conventionally, for example, JP-A-2000-142
As disclosed in Japanese Patent Publication No. 311, a floor sensor is provided at the center of the vehicle body and outputs a signal corresponding to an impact applied to the part, and a parameter based on an output signal of the floor sensor exceeds a threshold value. There is known an activation control device of an airbag device for deploying an airbag to a vehicle. This device includes a satellite sensor arranged at the front of the vehicle body and outputting a signal according to an impact applied to the site,
As the impact applied to the front part of the vehicle body detected based on the output signal of the satellite sensor increases, the threshold value is reduced significantly. In such a configuration, the greater the impact applied to the front portion of the vehicle body, the more easily the airbag deploys. Therefore,
According to the above-described conventional device, it is possible to activate the airbag device for protecting the occupant at an early timing after the collision.

[0003]

By the way, actually,
Even if no impact due to a collision is applied to the front part of the vehicle body, the output signal of the satellite sensor may show a large impact due to running on a rough road, noise, or the like. When such a situation occurs, in the above-described conventional device, the threshold value for deploying the airbag decreases in accordance with the output signal of the satellite sensor. For this reason, in the above-mentioned conventional device, there is a possibility that the airbag is easily deployed even if no impact due to the collision is applied to the front portion of the vehicle body.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and provides a start-up control device for an occupant protection device that can start the occupant protection device at a timing according to the degree of collision occurring in a vehicle. The purpose is to provide.

[0005]

The above object is achieved by the present invention.
And a first sensor that is disposed at a predetermined position in the vehicle body and outputs a signal corresponding to an impact applied to the disposed portion, and a parameter based on an output signal of the first sensor is a predetermined sensor. Activation control means for activating the occupant protection device when the threshold value is exceeded, wherein the activation control device for the occupant protection device is provided at a front portion of the vehicle body in front of the disposition position of the first sensor, A second sensor that outputs a signal corresponding to the impact applied to the disposition portion; and an integrated value of deceleration due to the impact based on an output signal of the first sensor;
Collision degree determining means for determining the degree of collision occurring on the vehicle based on the relationship between the integrated value of the deceleration due to the impact based on the output signal of the sensor, and the collision determined by the collision degree determining means Threshold changing means for changing the predetermined threshold in accordance with the degree of the occupant protection device.

According to the first aspect of the present invention, the occupant protection device is activated when a parameter based on an output signal of the first sensor exceeds a predetermined threshold. Generally, when a vehicle collides, a front portion of the vehicle body starts to decelerate faster than a rear portion thereof, and a speed difference occurs between the front portion of the vehicle body and a rear portion thereof. The speed difference between the front part and the rear part of the vehicle body becomes larger as the collision becomes more severe. In the present invention, the degree of collision occurring in the vehicle is determined by the integrated value of the deceleration due to the impact based on the output signal of the first sensor and the integrated value of the deceleration caused by the first sensor. The determination is made based on the relationship with the integrated value of the deceleration due to the impact based on the output signal of the second sensor. In this case, the degree of collision occurring in the vehicle is accurately determined. The predetermined threshold value for starting the occupant protection device is changed according to the degree of collision determined as described above. Thus, according to the present invention,
The occupant protection device can be activated at a timing according to the degree of collision occurring in the vehicle.

In this case, as described in claim 2, in the activation control device for the occupant protection device according to claim 1, the collision degree determining means includes a deceleration due to an impact based on an output signal of the second sensor. It may be determined that the greater the integrated value of the first value is compared to the integrated value of the deceleration due to the impact based on the output signal of the first sensor, the greater the degree of the collision is.

By the way, even when the output signal of the second sensor indicates an extremely large impact due to running on a rough road, noise, or the like, the integrated value of the deceleration due to the impact may be large. In such a situation, if the impact is not transmitted to the location where the first sensor is provided, or if the impact transmitted to the location where the first sensor is provided is small, the output signal of the second sensor is used. The integral value of the deceleration due to the impact becomes significantly larger than the integral value of the deceleration due to the impact based on the output signal of the first sensor. In this case, if the degree of collision is determined based on the relationship between these integrated values, and the predetermined threshold value is changed in accordance with the degree of collision, the occupant may be irrespective of the collision of the vehicle. The protection device is easily activated. In this regard, the determination of the degree of collision can be made based on the relationship between the two integral values after a relatively large impact is transmitted to the portion where the first sensor is provided and the portion is greatly decelerated by the impact. Is appropriate.

Therefore, according to a third aspect of the present invention, in the activation control device for an occupant protection device according to the first aspect, the integrated value of the deceleration due to the impact based on the output signal of the first sensor reaches a predetermined value. Until then, a collision degree determination prohibition unit that prohibits the collision degree determination unit from determining the degree of the collision may be provided.

When the collision continues to some extent, the first or second sensor may output an abnormal signal which cannot be normally displayed due to the deformation of the vehicle body. In this case, the degree of collision is determined based on the relationship between the integrated values of deceleration due to impact based on the output signals of the first and second sensors, and a predetermined threshold value is changed according to the degree of collision. In this case, the activation of the occupant protection device is not performed at an appropriate timing. In this regard, the determination of the degree of collision is based on the first
Before the second sensor outputs an abnormal signal due to the deformation of the vehicle body, it is appropriate to perform the operation based on the relationship between the two integral values.

According to a fourth aspect of the present invention, in the activation control device for an occupant protection device according to the first aspect, the integrated value of the deceleration due to the impact based on the output signal of the first sensor reaches a predetermined value. After that, a collision degree determination prohibition unit that prohibits the collision degree determination unit from determining the degree of the collision may be provided.

[0012]

FIG. 1 is a system configuration diagram of an activation control device for an occupant protection device according to an embodiment of the present invention.
The system of this embodiment includes an electronic control unit (hereinafter, referred to as an ECU) 12 mounted on a vehicle 10.
It is controlled by the CU 12. Further, the system of the present embodiment includes a floor sensor 14 disposed near the floor tunnel in the center of the vehicle body, and a satellite sensor 16 disposed in the center of the front part of the vehicle body. Each of the floor sensor 14 and the satellite sensor 16 is an electronic deceleration sensor that outputs a signal corresponding to the magnitude of the impact (that is, deceleration) in the vehicle front-rear direction that acts on each disposed portion.

The ECU 12 includes an input / output circuit (I / O) 2
0, a central processing unit (hereinafter, referred to as a CPU) 22, a read-only memory (hereinafter, referred to as a ROM) 24 in which processing programs and tables necessary for calculations are stored in advance,
It comprises a random access memory (hereinafter referred to as a RAM) 26 used as a work area, and a bidirectional bus connecting these elements.

The above-described floor sensor 14 and satellite
The sensor 16 is connected to an input / output circuit 20 of the ECU 12.
ing. The output signal of the floor sensor 14 and the satellite
The output signals of the sensor 16 are input to the input / output circuit 20 respectively.
Supplied and stored in RAM as appropriate according to instructions from CPU 22
Is done. The ECU 12 receives the output signal of the floor sensor 14
Of the deceleration acting on the center of the vehicle body based on the_FDetect
Output, and based on the output signal of the satellite sensor 16.
Of the deceleration acting on the front center of the vehicle body G _SDetect
I do.

The system according to the present embodiment further includes an airbag device 30 mounted on the vehicle 10 and operated to protect an occupant. The airbag device 30 has a drive circuit 32, an inflator 34, and an airbag 36. The inflator 34 incorporates an ignition device 38 connected to the drive circuit 32 and a gas generating agent (not shown) that generates a large amount of gas by the heat generated by the ignition device 38.
The airbag 36 is inflated and deployed by the generation of gas. The airbag 36 is provided at a position interposed between an occupant of the vehicle 10 and a vehicle-mounted component when inflated and deployed.

The drive circuit 32 of the airbag device 30
It is connected to the input / output circuit 20 of the CU 12. The airbag device 30 is activated when a drive signal is supplied from the input / output circuit 20 to the drive circuit 32, and deploys the airbag 36. The CPU 22 of the ECU 12 includes an activation control unit 40 and a threshold change pattern changing unit 42. CP
Activation control unit 40 of U22 in accordance with the processing program stored in the ROM 24, based on the deceleration G _F detected by using an output signal of the floor sensor 14 calculates a predetermined parameter as described below, is the calculated It is determined whether or not the parameter exceeds a predetermined threshold value SH, and supply of a drive signal from the input / output circuit 20 to the drive circuit 32 of the airbag device 30 is controlled based on the determination result. Further, the threshold change pattern changing unit 42 calculates predetermined parameters based on the decelerations G _F and G _S based on the output signals of the floor sensor 14 and the satellite sensor 16 as described later, and based on the relationship between these parameters. Thus, the predetermined threshold value SH used in the activation control unit 40 is appropriately set.

Next, the contents of processing performed by the CPU 22 of the present embodiment will be described.

In the present embodiment, the activation control section 40, the following equation in the deceleration G _F which is detected based on the output signal of the floor sensor 14 (1) and the calculated value by performing a predetermined operation as (2) _Find V ₁₀ and V _n1 . That is, the traveling vehicle 1
If the deceleration G _F is applied to the 0, for car object (e.g., passenger) is to accelerate forward relative to the vehicle 10 by the inertial force, the relative speed with respect to the vehicle 10 in the vehicle body, the deceleration G _F It can be obtained by time integration.
Moreover, instantaneous speed variation with respect to the vehicle 10 in the vehicle body can be determined by interval integral of the deceleration G _F at a predetermined time (e.g., 10 msec). Incidentally, in FIG. 2, during high-speed collision, when medium speed collision, and diagram showing the relationship between the calculated value V ₁₀ and V _n1 in each of the low speed collision is shown.

[0019]

(Equation 1)

[0020]

(Equation 2) After calculating the operation values V ₁₀ and V _n1 , the activation control unit 40 calculates a value determined by the relationship between the two operation values V ₁₀ and V _n1 .
The threshold value is compared with a threshold value SH as a determination map set by the threshold value change pattern changing unit 42.

[0021] Figure 3, in this embodiment, the change pattern of the threshold SH that functions as a determination map for the air bag device 30 in relation to the calculated value V ₁₀ and V _n1 (hereinafter, referred to as a threshold changing pattern ) Is shown. FIG. 3 shows Hi-map and L-map as threshold change patterns.
Six patterns of an o1 map, Lo2 map, Lo3 map, Lo4 map, and Lo5 map are shown. In this embodiment, the Hi map is a reference map in advance, and the threshold value SH is Hi → Lo1 → Lo2 → L
o3 → Lo4 → Lo5.

In the present embodiment, the threshold value changing pattern changing portion 42 stores threshold changing pattern of the relationship between the V _n1 and calculation value V ₁₀ previously determined experimentally as shown in FIG. 3 I have. Each of these threshold value change patterns functions as a boundary line for determining whether or not it is necessary to activate the airbag device 30 when an impact is applied to the vehicle 10. It is selected according to the intensity.

That is, it is necessary to set the threshold change pattern so that the more severe the collision that occurs in the vehicle 10, the more easily the airbag device 30 is activated. The collision that occurs in the vehicle 10 becomes more severe as the speed at which the front portion of the vehicle body is deformed with respect to a portion behind it (hereinafter, referred to as a deformation speed) is higher. Therefore, the severity of the collision occurring in the vehicle 10 can be grasped as the deformation speed of the front part of the vehicle body with respect to the central part of the vehicle body.

FIG. 4 is a view for explaining a method of setting a threshold change pattern in this embodiment. In this embodiment, the threshold value changing pattern changing portion 42, the operation value V by performing a predetermined operation as the following equation (3) in the deceleration G _S that is detected based on the output signal of the satellite sensor 16
_{Find n2} . FIG. 4 shows the relationship between calculated values V _n1 and V _n2 representing a map (hereinafter, referred to as a collision level determination map) for determining the severity of a collision (hereinafter, referred to as a collision level). .

[0025]

(Equation 3)Then, the threshold change pattern changing unit 42 outputs the floor cell.
Speed based on the output signal of the sensor 14 (calculated value
V_n1) And the vehicle based on the output signal of the satellite sensor 16
Front body speed (calculated value V_n2) Based on the relationship
Select and set the desired value change pattern. Specifically, the car
Front body speed V_n2Is the speed V at the center of the vehicle _n1Larger than
The more severe the collision that occurs on the vehicle 10
Thus, as shown in FIG.
A pattern with a small value SH is selected. That is, the operation
Value V_n1And V_n2Is the first level in FIG.
If it exists in the threshold region, the threshold change pattern is L
Select the o1 map and the values are in the second level area
The Lo2 map, select the above value and enter the third level
If it exists in the area, select the Lo3 map and
If it is in the 4 level area, select the Lo4 map,
Lo5 map if the above values exist in the fifth level area
Is selected, and the above value is set in any of the first to fifth level regions.
If none exists, the Hi map is selected.

In the present embodiment, the threshold value change pattern changing section 42 stores a collision level determination map for the relationship between the calculated values V _n1 and V _n2 experimentally determined in advance as shown in FIG. ing. The first level area is calculated value V
_n2 is set to a region closest to V _n1 , and the fifth level region is set to a region where the operation value V _n2 is farthest from V _n1 . Further, the first to fifth level regions are all limited to a region where the operation value V _n1 based on the output signal of the floor sensor 14 is equal to or more than the first predetermined value V ₁ and equal to or less than the second predetermined value V ₂ .

In the above configuration, the activation control unit 40
The value determined from the relationship between the calculated value V ₁₀ and V _n1, result of comparison with the threshold SH of the threshold changing pattern selected and set by the threshold value changing pattern changing portion 42, the value is the threshold When SH is exceeded, a drive signal is supplied from the input / output circuit 20 to the drive circuit 32 of the airbag device 30.
In this case, the airbag 36 is deployed by activating the airbag device 30. Meanwhile, value determined from the relationship between the calculated value V ₁₀ and V _n1 threshold SH
If not, no drive signal is supplied to the drive circuit 32 of the airbag device 30.

As described above, in this embodiment, the vehicle 1
The threshold value for starting the airbag device 30 is changed according to the severity of the collision occurring at zero, specifically, the deformation speed of the front part of the vehicle body with respect to the central part of the vehicle body. Therefore, the vehicle 1
The higher the speed 0 collides, the easier the airbag device 30 is activated. Therefore, according to the activation control device of the present embodiment, the airbag device 30 is activated earlier as the collision is more severe, so that the airbag device 30 is activated at an appropriate timing according to the severity of the collision. Become.

FIG. 5 is a flowchart showing an example of a control routine executed by the ECU 12 in the present embodiment to realize the above-described functions. The routine shown in FIG. 5 is a routine that is repeatedly started every predetermined time (for example, 100 μsec). When the routine shown in FIG. 5 is started,
First, the process of step 100 is performed.

In step 100, a process of detecting the decelerations G _F and G _S based on the output signal of the floor sensor 14 and the output signal of the satellite sensor 16 is executed.

In step 102, the above-mentioned step 100
Deceleration G detected in_F, G_SFor a certain period of time (eg,
10msec) Deceleration for the time from before to the present time t
Degree G _FV obtained by section integration of_Ten, Shock generation (t =
Deceleration G for all sections from 0) to the current time t_FThe ward
Value V obtained by integration between_n1And impact generation (t = 0)
Deceleration G for all sections from_SIs the interval product
Value V obtained by dividing_n2Is calculated.

In step 104, the mapping shown in FIG.
The operation value V by referring to the _n1, V_n2According to the relationship
The determined value belongs to any of the above-mentioned first to fifth level areas.
Is determined.

In step 106, a process for selecting and setting a map corresponding to the level to which the value determined by the relationship between the calculated values V _n1 and V _n2 belongs as the threshold value change pattern is executed.

[0034] At step 108, the calculated value V ₁₀ is, whether more than a threshold value SH in the operation value V _n1 on threshold changing pattern set in step 106 is determined. As a result, when it is determined that V ₁₀ > SH is established, the airbag device 30 needs to be activated, and the process of step 110 is executed next. On the other hand, if it is determined that V ₁₀ > SH is not established, there is no need to activate the airbag device 30, and therefore, step 110 is jumped to end the current routine.

In step 110, the airbag device 30
A process of supplying a drive signal to the drive circuit 32 is executed. When the process of step 110 is performed, gas is generated in the inflator 34 by the heat generated by the ignition device 38 of the airbag device 30, and the airbag 36 is inflated and deployed. When the process of step 110 ends, the current routine ends.

According to the above processing, the higher the deformation speed of the front part of the vehicle body with respect to the center part of the vehicle body, the greater the airbag device 30
It is possible to select and set a map having a small threshold value SH as a threshold value change pattern for determining whether or not to start up. That is, the threshold value change pattern can be changed according to the deformation speed of the front part of the vehicle body with respect to the central part of the vehicle body. For this reason, in the present embodiment, the more severe the collision, that is, the higher the speed of the collision of the vehicle 10, the easier the airbag device 30 is activated, and the earlier the airbag 36 is inflated and deployed. Therefore, according to the activation control device of the present embodiment, it is possible to activate the airbag device 30 at an appropriate timing according to the severity of the collision.

In this embodiment, as described above,
In all of the first to fifth level areas of the collision level determination map for determining the collision level of the vehicle 10, the calculated value V _n1 based on the output signal of the floor sensor 14 is equal to or more than the first predetermined value V ₁ and the second predetermined it is limited to the region which the value V ₂ less. In this configuration, the collision level is not determined before the calculated value V _n1 based on the output signal of the floor sensor 14 reaches the first predetermined value V ₁ and after the calculated value V _n1 reaches the second predetermined value V ₂ .

Therefore, the calculated value V _n2 based on the output signal of the satellite sensor 16 is reduced due to noise or the like on a rough road where the relative speed of the in-vehicle object at the front of the vehicle body with respect to the vehicle 10 may increase _{spontaneously.} Even if it is determined that the deformation speed of the front portion of the vehicle body with respect to the center portion of the vehicle body is large, the calculated value V _n1 based on the output signal of the floor sensor 14 is considerably large. Is prevented from being changed to a map having a smaller threshold SH. Therefore, according to the activation control device of the present embodiment, it is possible to avoid a situation in which the airbag device 30 is easily activated due to running on a rough road, noise, or the like. Can be suppressed.

Further, if the collision continues for a long period of time, the position of the floor sensor 14 or the position of the satellite sensor 16 is greatly deformed, and the output signal of the floor sensor 14 or the satellite sensor 16 is abnormal. , The threshold change pattern for activating the airbag device 30 is small even when it is determined that the deformation speed of the front portion of the vehicle body with respect to the center portion of the vehicle body is high. Is avoided.
Therefore, according to the activation control device of the present embodiment, when an abnormality occurs in the output signal of the floor sensor 14 or the satellite sensor 16 due to the progress of the vehicle deformation, the airbag device 3
0 can be easily activated, and malfunction of the airbag 36 can be suppressed.

In the above embodiment, the floor sensor 14 is the "first sensor" described in the claims.
The calculated value V ₁₀ obtained by applying a predetermined arithmetic operation to the deceleration G _F which is detected based on the output signal of the floor sensor 14
Is set to the “parameter” described in the claims, and the threshold value SH on the threshold change pattern is set to the “predetermined threshold value” described in the claims.
Corresponds to the “occupant protection device” described in the claims, and the satellite sensor 16 corresponds to the “second sensor” described in the claims.

In the above embodiment, the ECU 1
2 is a calculated value V ₁₀ based on the output signal of the floor sensor 14.
Is supplied from the input / output circuit 20 to the drive circuit 32 of the airbag device 30 when the threshold value exceeds the threshold value SH in the calculated value V _n1 on the threshold value change pattern. "Startup control means" described
However, a patent is obtained by determining a level area to which a value determined by a relationship between a calculation value V _n1 based on an output signal of the floor sensor 14 and a calculation value V _n2 based on an output signal of the satellite sensor 16 belongs on a map shown in FIG. The “collision degree determining means” described in the claims is used in step 1
Described in the claims by performing the process 06 is "threshold value change means" in operation value V _n1 is the first predetermined value V ₁ based on the output signal of the floor sensor 14 as shown in FIG. 4 in some cases a has collision level determination map existing in a region surrounded by the case where the second is a predetermined value V _2, calculation value V _n1 is the first predetermined value V based on the output signal of the floor sensor 14
It is claimed by not performing the determination of the collision level if more than a case and a second predetermined value V ₂ not reach ₁ "collision degree determination prohibition means" are realized respectively.

In the above embodiment, only one satellite sensor 16 for outputting a signal corresponding to an impact applied to the front of the vehicle body is provided at the front of the vehicle body. 16 may be disposed at the front of the vehicle body, and the degree of collision generated in the vehicle 10 may be determined based on the integrated value of the deceleration due to the impact based on each output signal.

In the above embodiment, each level area of the collision level determination map shown in FIG. 4 is divided linearly, but may be divided in a curved line.

As described above, according to the first and second aspects of the present invention, the occupant protection device can be activated at a timing corresponding to the degree of collision occurring in the vehicle.

According to the third aspect of the invention, it is possible to avoid a situation in which the occupant protection device is easily activated due to running on a rough road, noise, or the like, and to suppress malfunction of the occupant protection device. it can.

According to the fourth aspect of the present invention, when the output signal of the first or second sensor becomes abnormal due to the progress of the deformation of the vehicle body, the occupant protection device is easily activated. Thus, the occupant protection device can be prevented from malfunctioning.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram of an activation control device of an occupant protection device according to an embodiment of the present invention.

FIG. 2 shows the results of a high-speed collision, a medium-speed collision, and a low-speed collision.
Calculated value V for each_TenAnd V _n1In a diagram showing the relationship with
is there.

[3] In the present embodiment, a diagram showing the change patterns of the threshold SH that functions as a determination map for the air bag device relative to the calculated value V ₁₀ and V _n1.

FIG. 4 is a diagram for explaining a method of setting a threshold change pattern in the present embodiment.

FIG. 5 is a flowchart of an example of a control routine executed in the embodiment.

[Explanation of symbols]

Based on 12 electronic control unit (ECU) 14 floor sensor (first sensor) 16 satellite sensors (second sensor) 30 airbag apparatus 40 starts the control unit 42 threshold changing pattern changing portion G _F the output signal of the floor sensor deceleration G _S total interval integral value of the total interval integral value V _n2 G _S of interval integral value V _n1 G _F at a certain time of the deceleration V ₁₀ G _F based on the output signal of the satellite sensor

Claims (4)

[Claims] 1. A first sensor which is disposed at a predetermined position in a vehicle body and outputs a signal corresponding to an impact applied to the disposed portion, and a parameter based on an output signal of the first sensor is a predetermined sensor. Activation control means for activating the occupant protection device when the threshold value is exceeded, wherein the activation control device for the occupant protection device is provided at a front portion of the vehicle body ahead of the disposition position of the first sensor; A second sensor that outputs a signal corresponding to the impact applied to the disposition portion; and a second sensor that outputs an integrated value of deceleration due to the impact based on the output signal of the first sensor and an output signal of the second sensor. Collision degree determining means for determining the degree of collision occurring on the vehicle based on the relationship between the integrated value of the deceleration due to the impact, and the predetermined degree in accordance with the degree of collision determined by the collision degree determining means Change threshold And a threshold change unit that performs the following: an activation control device for an occupant protection device. 2. The activation control device for an occupant protection device according to claim 1, wherein the collision degree determination unit determines that an integrated value of deceleration due to an impact based on an output signal of the second sensor is equal to the first sensor. The start control device for the occupant protection device, wherein it is determined that the degree of the collision is greater as the integrated value of the deceleration due to the impact based on the output signal is larger. 3. The starting control device for an occupant protection device according to claim 1, wherein the collision degree determining means is performed until an integrated value of deceleration due to an impact based on an output signal of the first sensor reaches a predetermined value. And a collision degree determination prohibiting unit for prohibiting the determination of the degree of the collision based on the start-up control. 4. The start control device for an occupant protection device according to claim 1, wherein the collision degree determination is performed after an integrated value of deceleration due to an impact based on an output signal of the first sensor reaches a predetermined value. An activation control device for an occupant protection device, comprising collision degree determination prohibition means for prohibiting the determination of the degree of collision by means.