JP2000127891A - Ignition control method for vhielce occupant protection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To expand a rollover occupant restraint system at an optimum timing by providing a threshold setting step for setting a prescribed threshold to a small value in case of the front collision or side collision of a vehicle, compared with the case having no collision. SOLUTION: When no front collision or side collision of a vehicle is detected (S200), the threshold is set to S1 (S204). In case of θ>=S1 (S204), occurrence of a rollover requiring the expansion of a head protecting air bag in the vehicle is judged to expand the head protecting air bag (S206). On the other hand, when occurrence of the front collision or side collision of the vehicle is detected (S200), the threshold is set to a threshold S2 smaller than S1 (S208). It is judged whether the roll angle θ of the vehicle is the threshold S2 or more (S210). In case of θ>=S2, occurrence of the rollover requiring the expansion of the head protecting air bag in the vehicle is judged, and a switching element is laid in ON state in the rolling direction to expand the head protecting air bag (S206).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ignition control method for an occupant protection system for a vehicle, and more particularly, to an ignition control for an occupant restraint system for a rollover in accordance with the situation of an occupant in the vehicle when the vehicle rolls over. The present invention relates to an ignition control method for performing

[0002]

2. Description of the Related Art An airbag, which is a kind of vehicle occupant protection device, includes a frontal airbag which is deployed at the time of a frontal collision of a vehicle (hereinafter, referred to as a frontal collision) and a side collision of a vehicle (hereinafter, a side collision). ), And a rollover airbag that is deployed when the vehicle rolls over.

[0003] Generally, a rollover airbag is deployed when a rollover detection sensor provided independently in a vehicle detects a roll angular velocity (roll rate) or roll angle that is equal to or greater than a predetermined value. For example, JP-A-9-24
Japanese Patent Application Publication No. 0399 discloses a vehicle occupant posture assisting device including a roll angular velocity sensor for detecting a roll rate of a vehicle. According to this occupant posture assistance device, the roll angle of the vehicle is calculated based on the roll rate detected by the roll angular velocity sensor. When the detected roll rate and roll angle exceed a preset fixed value, it is determined that the vehicle has rolled over, and the rollover airbag is deployed.

[0004]

However, the rollover of the vehicle usually rarely occurs alone, and often occurs immediately after a frontal collision or a side collision. Specifically, for example, a high-height vehicle and a low-height vehicle collide with each other, and a high-height vehicle rolls over after riding on a low-height vehicle, or a high-height vehicle May roll over after being hit by a vehicle with a low vehicle height.

[0005] In such a case, an occupant moves in the vehicle due to an impact at the time of a front collision or a side collision before rollover occurs. Therefore, even if the roll rate or the roll angle that increases with the occurrence of the rollover of the vehicle exceeds the fixed value set in advance and then the airbag for rollover is deployed,
In some cases, proper protection of the occupants cannot be achieved. In particular, when the occupant does not wear a seat belt, the amount of movement of the occupant during a frontal collision or a side collision before the occurrence of a rollover is large, so that at the subsequent rollover, the airbag for the rollover is provided at an earlier timing. Needs to be expanded.

The present invention has been made in view of the above points, and provides an ignition control method for a vehicle occupant protection device that deploys a rollover occupant restraint device at an optimal timing according to the occupant's situation. The purpose is to:

[0007]

The above object is achieved by the present invention.
As described in the above, when at least one of the roll angle and the roll angular velocity of the vehicle exceeds a predetermined threshold value, the ignition control method of the vehicle occupant protection device for activating the rollover occupant restraint device, A collision determination step of determining whether or not a front collision or side collision has occurred, and when the vehicle has a front collision or side collision, the predetermined A threshold setting step of setting the threshold to a small value.

According to such an ignition control method, when a rollover occurs immediately after a frontal collision or a side collision of the vehicle, the threshold value compared with at least one of the roll angle and the roll angular velocity is determined by the threshold value of the vehicle. It is set to a smaller value than when there was no side collision. Therefore, when a rollover occurs after a frontal collision or a side collision of the vehicle, the occupant restraint device for rollover operates at a timing earlier than when rollover occurs alone.

The above object is also achieved by a vehicle which activates a rollover occupant restraint system when at least one of a roll angle and a roll angular velocity of the vehicle exceeds a predetermined threshold value. Control method for estimating a movement amount of a passenger in a vehicle, comprising: a threshold value changing a predetermined threshold value according to the estimated movement amount. And a changing step.

In such an ignition control method, the threshold value is changed according to the amount of movement of the occupant following a collision of the vehicle.
Therefore, when a rollover of the vehicle occurs, the rollover occupant restraint device can be operated at an appropriate timing according to the amount of movement of the occupant. According to a third aspect of the present invention, in the ignition control method for a vehicle occupant protection device according to the first or second aspect, a wearing determination step of determining whether the occupant wears a seat belt. When,
A threshold setting step of setting the predetermined threshold to a smaller value when the occupant does not wear a seat belt, compared to when the occupant wears a seat belt. Is achieved by the ignition control method described above.

When the occupant does not wear a seat belt,
The amount of movement of the occupant when a vehicle collision or the like occurs becomes larger than when the occupant wears a seat belt. Therefore, in the ignition control method of the present invention, the threshold value is set to a smaller value when the occupant does not wear the seat belt than when the occupant wears the seat belt. Therefore, even when the occupant does not wear the seat belt, the rollover occupant restraint device can be operated more quickly and at an appropriate timing.

According to a fourth aspect of the present invention, there is provided an ignition control method for a vehicle occupant protection device according to the first or second aspect, wherein the occupant determines whether or not an occupant is present in the passenger seat. In the determination step, when the occupant is present in the front passenger seat, the predetermined threshold value for the rollover occupant restraint device on the front passenger seat is set to a smaller value than when the occupant is not present in the front passenger seat. And a threshold setting step.

In such an ignition control method, when an occupant is present in the passenger seat, the threshold value is set to a smaller value than when no occupant is present in the passenger seat. Therefore, when the occupant is present in the passenger seat, the rollover occupant restraint device on the passenger seat side operates at an earlier timing when the vehicle rolls over than when the occupant does not exist in the passenger seat.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a description will be given of an ignition control system for implementing an ignition control method for a vehicle occupant protection device according to an embodiment of the present invention and a configuration of an occupant protection device controlled by ignition control. FIG. 1 is a layout diagram of an ignition control system and an occupant protection device in a vehicle.

As shown in FIG. 1, the occupant protection system applies tension to front airbags 12 and 14 disposed in front of a driver's seat and a passenger's seat, respectively. Pretensioner 16, 1 to be applied
8, side impact airbags 20 and 22 arranged on the side surfaces of the driver's seat and the passenger seat, and a head protection airbag 24 arranged from the front pillar on the driver's seat side and the passenger's seat side to the roof side rail; 26 and the like.

The ignition control system has an airbag control device 28. This airbag control device 28
Is stored inside the front floor center tunnel. Further, the airbag control device 28 includes a rollover sensor 30, side collision sensors 32 and 34, front collision sensors 36 and 38, a seat belt wearing sensor 40,
42, a seating sensor 44 for a passenger seat, a cut-off switch 46, and the like.

The rollover sensor 30 is disposed in the vicinity of the main body of the airbag control device 28, and detects a rollover that has occurred in the vehicle and the direction of the rollover (clockwise or counterclockwise). The side collision sensors 32 and 34 are disposed near the rear portions of the pretensioners 16 and 18, respectively, and detect side collision of the vehicle based on lateral acceleration generated in the vehicle. The front collision sensors 36 and 38 are disposed in the engine room, and detect a front collision of the vehicle based on longitudinal acceleration generated in the vehicle.

The seat belt wearing sensors 40 and 42 are respectively arranged in the buckles of the seat belts of the driver's seat and the passenger seat (not shown), and detect that the respective seat belts are worn. Further, the seating sensor 44 is disposed in the seat cushion of the passenger seat, and detects the seating of the occupant by detecting a load on the seat. The cut-off switch 46 is disposed on the instrument panel 48 in front of the driver's seat, and the front-end airbags 12 and 14, the side-impact airbags 20 and 22, and the head-protection airbags 24 and 26 are provided.
Of these, the airbag selected by the occupant is set to the deployment prohibited state.

The airbag controller 28 includes a rollover sensor 30, side collision sensors 32 and 34, front collision sensors 36 and 38, seat belt wearing sensors 40 and 42, and a seating sensor 44, as will be described in detail later. , And based on an input signal from the cutoff switch 46 or the like, the corresponding airbag is deployed, and the pretensioners 16, 1
Activate 8

FIG. 2 is a perspective view of the deployed side collision airbag 20 and the head protection airbag 24 on the driver's seat side. Before deployment, the head protection airbag 24 is stored from the front pillar to the roof side rail. Below the front pillar, an inflator 50 for deploying the head protection airbag 24 in the event of a side collision or rollover of the vehicle is built in. When a side collision or rollover occurs in the vehicle, the gas is supplied from the inflator 50 so that the head protection airbag 24 is supplied.
Deploys along the window on the side of the vehicle to prevent direct contact between the occupant's head and the side of the vehicle. Note that the head protection airbag 26 on the passenger seat side has the same configuration as the driver seat side.

FIG. 3 is a circuit diagram of the airbag control device 28 provided in the ignition control system. As shown in FIG. 3, the airbag control device 28 includes the rollover sensor 30, the side collision sensors 32 and 34, and the front collision sensor 3.
6, 38, seat belt wearing sensors 40, 42, and
In addition to the seating sensor 44, a power supply terminal 54, a backup capacitor 56, a front collision safing sensor 5
8, right side collision safing sensor 60, left side collision safing sensor 62, rollover safing sensor 64,
A front and rear G sensor 66, a left and right G sensor 68, a CPU 70, an ignition circuit 100, and the like are provided.

A predetermined power supply voltage is applied to the airbag device 28 from a power supply circuit 52 connected via a power supply terminal 54. Further, a backup capacitor 56 is connected to the power supply terminal 54. The backup condenser 56 supplies electric power for the airbag control device 28 to operate the occupant protection device including the pretensioner and the airbag.

The power terminal 54 is further connected to a front collision safing sensor 58, a right collision safing sensor 60, a left collision safing sensor 62, and a rollover safing sensor 64. The front collision safing sensor 58, the right collision safing sensor 60, the left collision safing sensor 62, and the rollover safing sensor 64 are each a normally-open mechanical sensor. The front collision safing sensor 58 is closed when an acceleration exceeding a predetermined value occurs in the front-rear direction of the vehicle, and the right collision safing sensor 60 and the left collision safing sensor 62
Is closed when a vehicle lateral acceleration exceeding a predetermined value occurs, and the rollover safing sensor 64 is closed when a roll angular velocity exceeding a predetermined value occurs in the vehicle. The front collision safing sensor 58, the right collision safing sensor 60, the left collision safing sensor 62, and the rollover safing sensor 64 are connected to the ignition circuit 100.

The front and rear G sensor 66 detects front and rear acceleration generated on the vehicle, and the left and right G sensor 68 detects lateral acceleration generated on the vehicle. Front and rear G sensor 66,
A detection signal from the left and right G sensors 68 is given to the CPU 70. The CPU 70 includes an airbag control device 28.
Detection signals from the rollover sensor 30, the side collision sensors 32 and 34, the front collision sensors 36 and 38, the seat belt wearing sensors 40 and 42, and the seating sensor 44 which are arranged outside the main body are also given. Then, the CPU 70 turns on a corresponding switching element in the ignition circuit 100 based on a detection signal given from each sensor, as described later in detail.

FIG. 4 is a circuit diagram of the ignition circuit 100. As shown in FIG. 4, the front collision safing sensor 58 has a switching element 10 via a diode 102.
6, 108 are connected. The diode 102 is connected to the switching element 10 from the front collision safing sensor 58 side.
Only the current flowing to the side of 6, 108 is allowed. The switching elements 106 and 108 have squibs 110,
112 is connected. Squibs 110 and 112
The ignition causes the front airbag 12 on the driver's seat side and the front airbag 14 on the passenger's seat side to deploy, respectively. The squibs 110 and 112 are connected to ground lines via switching elements 114 and 116, respectively.

The front collision safing sensor 58 includes:
The switching elements 120, 1
22 are connected. The diode 118 is connected to the switching elements 120, 1 from the front collision safing sensor 58 side.
Only the current flowing to the side 22 is allowed. Switching elements 120 and 122 have squibs 124 and 12 respectively.
6 are connected. When the squibs 124 and 126 are ignited, the pretensioner 16 on the driver's seat side and the pretensioner 18 on the passenger seat side are operated, respectively. The squibs 124 and 126 are connected to ground lines via switching elements 128 and 130, respectively.

According to the above configuration, the switching element 1 is switched on when the front collision safing sensor 58 is closed.
06 and 114 are turned on, so that squib 1
10 is ignited and the switching elements 108 and 116 are turned on, so that the squib 112 is ignited,
When the switching elements 120 and 128 are turned on, the squib 124 is ignited, and when the switching elements 122 and 130 are turned on, the squib 126 is ignited.

A switching element 134 is connected to the right-side collision safing sensor 60 via a diode 132, and a switching element 138 is connected via a diode 136.
Is connected. The diode 132 allows only a current flowing from the right-side collision safing sensor 60 to the switching element 134, and the diode 136 allows only a current traveling from the right-side collision safing sensor 60 to the switching element 138. Switching element 13
4 and 138 are connected to squibs 140 and 142, respectively. The squib 140 deploys the side collision airbag 20 on the driver's seat side by being ignited. The squib 142 is ignited to deploy the head protection airbag 24 on the driver's seat side. The squibs 140 and 142 are respectively connected to the switching element 14.
4, 146 are connected to the ground line.

The right-side collision safing sensor 60 also
It is connected to the connection between the diode 118 and the switching elements 120 and 122 via the diode 148. The diode 148 allows only a current flowing from the right-side collision safing sensor 60 to the switching elements 120 and 122. According to the above configuration, in a state where the right-side collision safing sensor 60 is in the closed state, the squibs 140 are ignited by the switching elements 134 and 144 being turned on, and the switching element 138 is turned on.
And 146 are turned on so that the squib 142
Are ignited, and the squibs 124 are ignited when the switching elements 120 and 128 are turned on, and the squibs 126 are ignited when the switching elements 122 and 130 are turned on.

A switching element 152 is connected to the left side safing sensor 62 via a diode 150, and a switching element 156 is connected via a diode 154.
Is connected. The diode 150 allows only a current flowing from the left-side collision safing sensor 62 to the switching element 152, and the diode 154 allows only a current traveling from the left-side collision safing sensor 62 to the switching element 156. Switching element 15
2, 156 are connected to squibs 158, 160, respectively. The squib 158 is ignited to deploy the side collision airbag 22 on the passenger seat side. The squib 160 is ignited to deploy the head protection airbag 26 on the passenger seat side. The squibs 158 and 160 are connected to the switching element 16 respectively.
2, 164 are connected to the ground line.

The left-hand side safing sensor 62 also
The diode 118 described above via the diode 166,
148 and the connection between the switching elements 120 and 122. The diodes 166 are connected to the switching elements 120 and 122 from the left-hand side safing sensor 62 side.
Only the current going to the side is allowed. According to the above configuration,
In a situation in which the left collision sensor 62 is in the closed state, the squibs 158 are ignited by the switching elements 152 and 162 being turned on, and the squibs 160 are ignited by the switching elements 156 and 164 being turned on. , Switching elements 120 and 1
When squib 124 is turned on, squib 124 is ignited, and when switching elements 122 and 130 are turned on, squib 126 is ignited.

The rollover safing sensor 64 is
It is connected to the connection between the diode 136 and the switching element 138 via the diode 168.
The diode 168 allows only a current flowing from the rollover safing sensor 64 side to the switching element 138 side. The rollover safing sensor 64 is
Also, the diode 1 described above via the diode 170
It is connected to the connection between the switching element 54 and the switching element 156. The diode 170 allows only a current flowing from the rollover safing sensor 64 side to the switching element 156 side. Rollover safing sensor 6
4 further includes the above-described diodes 118, 148, and 166 and the switching element 12 via the diode 172.
0, 122 are connected. Diode 1
Reference numeral 72 allows only a current flowing from the rollover safing sensor 64 to the switching elements 120 and 122.

According to the above configuration, when the rollover safing sensor 64 is in the closed state, the squibs 142 are ignited by the switching elements 138 and 146 being turned on, and the switching elements 156 and 164 are turned on. The state causes the squib 160 to be ignited, the switching elements 120 and 128 being turned on, the squib 124 being ignited, and the switching elements 122 and 130 being turned on, the squib 126 being ignited.

As described above, the diodes 102, 118, 132, 136, 148, 15
By providing 0, 154, 166, 168, 170, 172, misfire of each squib is prevented. For example, under the condition that the front collision safing sensor 58 is closed by the diodes 148, 166, and 172, and the right collision safing sensor 60, the left collision safing sensor 62, and the rollover safing sensor 64 are open,
The power supply voltage is prevented from being supplied to the squibs 140, 158, 142, 160 via the front collision safing sensor 58. Therefore, in this situation, the switching elements 134, 144, 152, 1
No matter which of 62, 138, 146, 156, 164 is turned on, the squibs 140, 158, 142, 160
Is not ignited. Therefore, when a front collision of the vehicle occurs, the side collision airbags 20 and 22 and the head protection airbag 2
Unnecessary deployment of 4, 26 is prevented.

The CPU 70 shown in FIG. 3 detects the presence or absence of a front collision based on detection signals given from the front collision sensors 36 and 38 and the front and rear G sensor 66. And C
When the PU 70 detects the occurrence of a frontal collision of the vehicle, the PU 70 turns on the switching elements 106, 114, 108, and 116, thereby igniting the squibs 110 and 112 and simultaneously switching the switching elements 120, 128, 122 and 1
By turning on the squib 30, the squibs 124, 1
26 is ignited.

The front collision safing sensor 58 is connected to the CPU 7
0 is set to a closed state at an acceleration lower than the acceleration for detecting the occurrence of a front collision of the vehicle. Therefore, under the situation where the CPU 70 properly detects the occurrence of the front collision, the front collision safing sensor 58 is in the closed state. In this case, the switching elements 106, 114, 10
8, 116 and switching elements 120, 128, 12
2 and 130 are turned on, so that the squib 11
0, 112 and the squibs 124, 126 are ignited, the front collision airbags 12, 14 are deployed, and the pretensioners 16, 18 are actuated to instantly wind up the slack in the seat belt, thereby minimizing the amount of movement of the occupant. Limit.

On the other hand, for example, due to the influence of electrical noise and the like,
If the CPU 70 erroneously detects a front collision despite no front collision, the front collision safing sensor 58 is kept open. In this case, the switching element 1
06, 114, 108, 116 and switching element 1
Even if 20, 128, 122 and 130 are turned on,
The squibs 110 and 112 and the squibs 124 and 126 are not ignited.

Therefore, according to the above configuration, the squib is ignited only when the front collision safing sensor 58 is closed and the switching element corresponding to the front collision of the vehicle is turned on. Therefore, malfunctions of the head protection airbags 24 and 26 and the pretensioners 16 and 18 due to electric noise or the like can be prevented.

The CPU 70 includes the side collision sensor 32,
Based on the detection signals provided from the right and left G sensors 68, it is detected whether or not a side collision has occurred. And CPU7
0, for example, when the occurrence of a side collision on the right side of the vehicle is detected, the switching elements 134, 144, 138, 146
By turning on the squibs 140 and 142
And the switching elements 120, 12
By turning on 8, 122 and 130, the squibs 124 and 126 are ignited.

The side collision safing sensor 60 includes a CPU 7
0 is closed at an acceleration lower than the acceleration for detecting the occurrence of a side collision on the right side of the vehicle. Therefore, under the situation where the CPU 70 properly detects the occurrence of the side collision, the side collision safing sensor 60 is in the closed state. In this case, the switching elements 134 and 14
4, 138, 146 and switching elements 120, 12
When the squibs 140 and 142 and the squibs 124 and 126 are ignited by turning on 8, 122 and 130, the side collision airbag 20 and the head protection airbag 24 on the driver's seat side are deployed, and the Tensioner 16, 1
8 is activated.

On the other hand, for example, under the influence of electrical noise,
Despite no side collision occurring on the right side of the vehicle, the CPU 7
When 0 detects a side collision erroneously, the side collision safing sensor 60 is kept open. In this case, even if the switching elements 134, 144, 138, and 146 and the switching elements 120, 128, 122, and 130 are turned on, the squibs 140 and 142 and the squib 12
4, 126 will not be ignited.

Therefore, according to the above configuration, the squib is ignited only when the side collision safing sensor 60 is closed and the switching element corresponding to the side collision on the right side of the vehicle is turned on. Therefore, the side collision airbag 20, the head protection airbag 24, and the pretensioners 16, 18 due to electric noise or the like are generated.
Can be prevented from malfunctioning.

When the CPU 70 detects the occurrence of a side collision on the left side of the vehicle, the CPU 70 switches the switching elements 152, 16
By turning on 2, 156 and 164, the squibs 158 and 160 are ignited to deploy the side collision airbag 22 and the head protection airbag 26 on the passenger seat side, and the switching elements 120 and 128 are turned on. , 122, 1
By turning on the squib 30, the squibs 124, 1
26 is ignited to activate the pretensioners 16,18.

The side collision safing sensor 62, like the side collision safing sensor 60, is configured to be closed at an acceleration lower than the acceleration at which the CPU 70 detects the occurrence of a side collision on the left side of the vehicle. ing. Therefore, CP
When U70 erroneously detects a side collision on the left side of the vehicle, the side collision safing sensor 62 is held in the open state, so that the squibs 158, 160 and the squibs 124, 12
6 is prevented from misfiring.

Therefore, according to the above configuration, the squib is ignited only when the side collision safing sensor 62 is closed and the switching element corresponding to the side collision on the left side of the vehicle is turned on. Therefore, the side collision airbag 22, the head protection airbag 26, and the pretensioners 16 and 18 on the passenger seat side caused by electric noise and the like.
Can be prevented from malfunctioning.

Further, the CPU 70 detects whether or not the vehicle has rolled over and its direction based on the detection signal given from the rollover sensor 30. And
When the CPU 70 detects the occurrence of the rollover of the vehicle, the switching elements 120, 128, 122, 130
Is turned on, so that the squibs 124 and 126
The pretensioners 16 and 18 are operated by the ignition of. At the same time, depending on the direction of the rollover, switching element 138, 146 or switching element 156,
By turning on the squib 164, the squib 142 or 160 is ignited. That is, when the clockwise rollover (the direction of the driver's seat is downward) has occurred, the CPU 70 attempts to deploy the airbag 24 for protecting the head of the driver's seat by ignition of the squib 142. On the other hand, if a counterclockwise (passenger seat downward) rollover has occurred, the CPU 70 sets the squib 160
Of the airbag 26 for protecting the head on the passenger side by the ignition of the vehicle.

In the above configuration, the operation timings of the pretensioners 16 and 18 are set at the same time as the deployment of the head protection airbags 24 and 26, but are performed earlier than the deployment of the head protection airbags 24 and 26. May be. Also,
When a rollover occurs, the airbag for head protection corresponding to the roll direction is deployed, and the roll angle θ of the vehicle is further increased.
May exceed a predetermined value (for example, θ = 180 °), the head protection airbag on the opposite side may be deployed. When a rollover occurs, the left and right head protection airbags 24 and 26 may be simultaneously deployed.

The rollover safing sensor 64 is
The CPU 70 is configured to be closed at an angular velocity lower than the roll angular velocity at which the rollover of the vehicle is detected. Therefore, the rollover safing sensor 64 is in a closed state under the situation where the CPU 70 properly detects the occurrence of the rollover. Therefore, at this time, the switching elements 120, 128, 122, 13
When 0 is turned on, the squibs 124 and 126 are turned on.
Is ignited, and the pretensioners 16 and 18 operate.
Further, when the switching elements 138 and 146 are turned on, the squib 142 is ignited, the driver-side head protection airbag 24 is deployed, and the switching element 15 is turned on.
When the squibs 160 and 164 are turned on, the squib 160 is ignited, and the head protection airbag 26 on the passenger seat side is deployed.

On the other hand, for example, under the influence of electric noise,
CPU 70 despite rollover not occurring
, The rollover safing sensor 64 is kept open. In this case, the switching elements 138, 146, 156, 16
4 and switching elements 120, 128, 122, 13
Even if 0 is turned on, the squibs 142 and 160 and the squibs 124 and 126 are not ignited.

Therefore, according to the above configuration, the squib is ignited only when the rollover safing sensor 64 is closed and the switching element corresponding to the rollover of the vehicle is turned on. Therefore, the airbag 2 for protecting the head caused by electric noise and the like
Malfunctions of the pretensioners 16 and 18 and the pretensioners 16 and 18 can be prevented.

In this embodiment, the CPU 70 determines that the roll angle θ or the roll angular velocity R of the vehicle is equal to a predetermined threshold value S.
Is exceeded, the occurrence of rollover of the vehicle is detected, and the head protection airbags 24 and 26 are deployed. However, if a rollover occurs after a frontal collision or a side collision, the occupant moves in the vehicle due to the impact of the frontal collision or the side collision. There is a possibility that the bags 24 and 26 are not deployed in time, so that proper protection of the occupant cannot be achieved.

On the other hand, according to the ignition control method of this embodiment, when a rollover occurs after a frontal collision or a side collision of the vehicle, the threshold value for judging the rollover is changed to a lower value. It is characterized in that the head protection airbags 24 and 26 are deployed and the pretensioners 16 and 18 are activated at a timing earlier than when rollover occurs alone.

FIG. 5 shows an air bag 2 for protecting the head when the vehicle rolls over in this embodiment.
4 is a flowchart showing a routine executed by a CPU 70 to develop the programs 4 and 26. Note that the routine shown in FIG. 5 is a regular interrupt routine started at regular time intervals. When the routine shown in FIG. 5 is started, first, in step 200, it is determined whether or not a front collision or a side collision has occurred in the vehicle. In step 200,
If the occurrence of frontal collision and side collision of the vehicle is not detected,
In step 202, the threshold is set to S1. Then, the process of step 204 is executed.

In step 204, it is determined whether or not the roll angle θ of the vehicle is equal to or greater than a threshold value S1. If θ ≧ S1 is not satisfied in step 204, it is determined that the vehicle has not undergone a rollover requiring deployment of the head protection airbags 24, 26, and the current routine ends. On the other hand, if θ ≧ S1 is satisfied in step 204, it is determined that a rollover in which the head protection airbags 24 and 26 need to be deployed has occurred in the vehicle. The switching elements 138, 14
6 or the switching elements 156 and 164 are turned on, and the head protection airbag 24 or 26 is deployed.

On the other hand, if the occurrence of a frontal collision and side collision of the vehicle is detected in step 200, the process proceeds to step 2
At 08, the threshold is set to S2, which is smaller than S1. Then, the process of step 210 is executed. In step 210, it is determined whether or not the roll angle θ of the vehicle is equal to or greater than a threshold value S2. If θ ≧ S2 is not satisfied in step 210, it is determined that the vehicle has not undergone a rollover requiring deployment of the head protection airbags 24, 26, and the current routine ends. On the other hand, in step 210,
If θ ≧ S2 holds, the head protection airbag 2
It is determined that a rollover that needs to deploy 4, 26 has occurred in the vehicle, and in the following step 206,
The switching elements 138 and 146 or the switching elements 156 and 164 are turned on according to the roll direction,
The head protection airbag 24 or 26 is deployed. It is assumed that the threshold values S1 and S2 are set to values that can surely protect the occupant during rollover in consideration of the type of the vehicle and the like.

As described above, according to the routine shown in FIG. 5, when the rollover occurs immediately after the frontal collision or the side collision of the vehicle, the threshold value is changed from S1 to a smaller value S2. Therefore, when a rollover occurs after a frontal collision or a side collision of the vehicle, the head protection airbags 24 and 26 are deployed at an earlier timing than when the rollover occurs alone. Therefore, according to the ignition control method of the present embodiment, even if a rollover occurs after a frontal collision or a side collision of the vehicle, the deployment of the head protection airbags 24 and 26 is not delayed, and the occupant's head is moved. Appropriately protected.

Next, a second embodiment of the present invention will be described. The ignition control method according to the present embodiment is characterized in that an optimal threshold value is set according to the amount of movement of an occupant in a vehicle. FIG. 6 is a flowchart showing a routine executed by the CPU 70 in order to deploy the head protection airbags 24, 26 when the vehicle rolls over in the present embodiment. Note that the routine shown in FIG. 6 is a periodic interruption routine started at regular time intervals.

When the routine shown in FIG. 6 is started, first, the processing of step 300 is executed. Step 30
In 0, the acceleration G _x in the longitudinal direction G sensor 66 detects longitudinal acceleration G in the lateral direction left and right sensor 68 detects
Based on _y, the estimated amount of movement of the longitudinal and lateral directions of the vehicle occupant by a predetermined value or more acceleration occurs in the vehicle D _x, D _y
Is calculated. For example, even if the occupant moves due to the accelerations G _x and G _y, it is considered that the occupant returns to the original position after a certain period of time. Therefore, the estimated movement amounts D _x and D _y can be obtained by the following equations (1) and (2) that integrate the accelerations G _x and G _y over the immediately preceding predetermined time t0 (for example, 500 ms).

[0059]

(Equation 1)

The movement amount D_x, D_yThe formula for
It is not limited to the expressions (1) and (2). For example, when an occupant moves
Front and back and left and right acceleration that can withstand without
Re G _x0, D_y0Then, this acceleration G_x0, D_y0Exceeds
It is thought that the acceleration is reflected as the movement of the occupant
And the amount of movement D_x, D_yBy the following equations (3) and (4).
You may ask for it.

D _x = ∫ (G _x -G _x0 ) dt (3) D _y = ∫ (G _y -G _y0 ) dt (4) When the processing of step 300 is completed, Step 3
02 is executed. In step 302, the calculated amount of movement D _x, based on D _y, the movement amount D _x, is larger numerical S _xy in accordance with an increase in D _y are calculated. here,
Assuming that k ₀ is a constant, the numerical value S _xy is obtained, for example, by the following equation (5).

[0062]

(Equation 2)

After the numerical value _Sxy is calculated by the processing of step 302, the processing of step 304 is executed. In step 304, when the vehicle rolls over, two thresholds S3 and S4 are set as criteria for determining whether to deploy the head protection airbags 24 and 26. Here, the fixed value is set to F1, F2, a function value determined in accordance with the numerical _{S xy f1 (S xy),} f2 (S xy), and when the threshold S3, S4 is, for example, the following formula It is determined by (6) and (7).

S3 = F1-f1 (S_xy) (6) S4 = F2-f2 (S_xy(7) The threshold value S3 is a value larger than the threshold value S4.
You. Also, the function f1 (S _xy), F2 (S_xy)
Value S_xySet to a larger value as the
Have been. Therefore, from the above equation (5), the numerical value S_xyIs moving
Quantity D_x, D_yThe value increases as the vehicle increases.
Acceleration G generated_x, G_yIs large and the crew at that time
Movement amount D in the vehicle_x, D_yThe greater the
S3 and S4 are set to small values.

The equations for calculating the threshold values S3 and S4 are as follows:
It is not limited to the above equations (6) and (7). For example, k ₁ ,
With k ₂ , k ₃ , k ₄ , and k ₅ as constants, thresholds S 3, S 4 may be obtained based on the movement amounts D _x , D _y as in the following equations (8), (9). . _{S3 = k 1 -k 2 D x} -k 3 D y ··· (8) S4 = S3-k 4 D x -k 5 D y ··· (9) , where the fixed value F1, F2, constant k _{1, k 2, k 3,} k
_4, k ₅ of the values and formulas (1) to (9), the function f1 (S _xy),
f2 (S _xy ) is a threshold value S according to the type of vehicle and the like.
3. Airbag 2 for head protection at optimal timing for S4
It is set to be a reference for developing 4, 26.

By the processing in step 304, the threshold value S
When S3 and S4 are calculated, next, the process of step 306 is executed. In step 306, the roll angle θ of the vehicle is calculated based on the detection signal given from the rollover sensor 30. Then, in step 308, it is determined whether or not the driver's seat belt is worn based on the detection signal from the driver's seat belt sensor 40. If it is determined in step 308 that the driver's seat-side seat belt is worn, then the process of step 310 is performed. On the other hand, if it is determined in step 308 that the driver's seat side seat belt is not worn, then the process of step 312 is executed.

In step 310, it is determined whether or not the previously calculated roll angle θ of the vehicle is equal to or greater than a threshold value S3. In step 310, if θ ≧ S3 is satisfied, it is determined that the vehicle has undergone a rollover that requires deployment of the driver-side head protection airbag 24, and then the process of step 314 is executed. Is done. In step 310, if θ ≧ S3 is not established, it is determined that the vehicle has not undergone a rollover in which the driver-side head protection airbag 24 needs to be deployed. The processing is executed.

On the other hand, in step 312, it is determined whether or not the previously calculated roll angle θ of the vehicle is equal to or greater than threshold value S4. In step 312, if θ ≧ S4 is satisfied, the driver-side head protection airbag 24
Is determined to have occurred in the vehicle, and the process of step 314 is executed. In step 312, if θ ≧ S4 is not satisfied, it is determined that the vehicle has not undergone rollover that requires deployment of the driver-side head protection airbag 24. The processing is executed.

In step 314, it is determined whether or not the deployment of the head protection airbag 24 on the driver's seat side is prohibited by the cut-off switch 46 arranged on the instrument panel 48. If the deployment of the driver-side head protection airbag 24 is prohibited in step 314, the driver-side head protection airbag 24 is not deployed, and the process of step 318 is executed. You. On the other hand, if it is determined in step 314 that the deployment of the driver-side head protection airbag 24 is not prohibited, the process of step 316 is performed.

In step 316, the switching element 1
38 and 146 are turned on, and the ignition of the squib 142 deploys the head protection airbag 24 on the driver's seat side. Thereby, appropriate protection of the driver's head is achieved. When the process of step 316 ends, the process of step 318 is executed next. In step 318, it is determined whether or not the front seat belt is worn based on the detection signal from the front seat belt sensor 42. If it is determined in step 318 that the passenger side seat belt is worn, then the process of step 320 is executed. On the other hand, if it is determined in step 318 that the passenger side seat belt is not worn, then the process of step 322 is executed.

In step 320, it is determined whether or not the previously calculated roll angle θ of the vehicle is equal to or greater than a threshold value S3. In step 320, if θ ≧ S3 is satisfied, it is determined that a rollover that requires deployment of the head protection airbag 26 on the passenger seat side has occurred in the vehicle, and then the process of step 324 is performed. Is done. In step 320, if θ ≧ S3 is not satisfied, it is determined that the vehicle does not have a rollover that needs to deploy the head protection airbag 26 on the passenger seat side, and the head on the passenger seat side is determined. This routine ends without the protection airbag 26 being deployed.

On the other hand, in step 322, it is determined whether or not the previously calculated roll angle θ of the vehicle is equal to or larger than the threshold value S4. In step 322, if θ ≧ S4 is satisfied, the head protection airbag 26 on the passenger seat side
Is determined to have occurred in the vehicle, and the process of step 324 is executed. In step 322, if θ ≧ S4 is not satisfied, it is determined that the vehicle has not undergone a rollover in which the passenger-side head protection airbag 26 needs to be deployed, and the passenger-side head This routine ends without the protection airbag 26 being deployed.

In step 324, it is determined whether or not the deployment of the head-protecting airbag 26 on the passenger seat side is prohibited by the cut-off switch 46 disposed on the instrument panel 48. In step 324, if the deployment of the passenger-side head protection airbag 26 is prohibited, the current routine ends without the passenger-side head protection airbag 26 being deployed. On the other hand, in step 324, the airbag 26 for protecting the head on the passenger side is used.
If is not prohibited, then step 326
Is performed.

At step 326, the switching element 1
56 and 164 are turned on, and the ignition of the squib 160 deploys the head protection airbag 26 on the passenger seat side. Thereby, appropriate protection of the head of the passenger in the passenger seat is achieved. When the process of step 326 ends, the current routine ends. As described above, the CPU 70
In the ignition control method that executes the routine shown in _{FIG. 5} , the larger the movement amounts D _x and D _y of the occupant in the vehicle, the larger the threshold value S
3, S4 is set to a small value. For this reason, when the vehicle rollover occurs, the head protection airbag 2 becomes earlier as the occupant movement amounts _Dx and _Dy are larger.
4, 26 are developed. Therefore, according to the ignition control method of the present invention, even when the occupant moves in the vehicle due to the occurrence of a vehicle collision or the like, the deployment of the head protection airbags 24 and 26 does not delay when the vehicle rolls over. The occupant's head is properly protected.

When the occupant does not wear the seat belt, a threshold value S4 lower than the threshold value S3 is used as a reference for the deployment timing of the head protection airbags 24 and 26. Therefore, even when the occupant moves largely because the occupant does not wear the seat belt at the time of the collision of the vehicle, the head protection airbags 24 and 26 during the rollover of the vehicle are provided.
Is further advanced, so that the deployment of the head protection airbags 24 and 26 is not delayed and the occupant's head is appropriately protected.

Next, a third embodiment of the present invention will be described. The ignition control method according to the present embodiment is characterized in that the CPU 70 controls the deployment of the head protection airbag 26 in accordance with the following routine in accordance with the following routine when the vehicle rolls over. . FIG. 7 shows an airbag 2 for protecting the head when the vehicle rolls over in this embodiment.
4 is a flowchart showing a routine executed by a CPU 70 to develop the programs 4 and 26. In the routine of this embodiment, the same processes as those in the routine shown in FIG. 6 are denoted by the same step numbers, and description thereof will be omitted.

When the routine shown in FIG. 7 is started and the processes of steps 300 to 316, which are the same as those of the second embodiment, are completed, the process of step 328 is executed. In step 328, it is determined whether or not an occupant is on the passenger seat based on the detection signal from the seating sensor 44 of the passenger seat. If it is determined in step 328 that there is no occupant in the passenger seat, then the process of step 330 is performed. On the other hand, if it is determined in step 328 that there is an occupant in the passenger seat, then the process of step 332 is executed.

At step 330, it is determined whether or not the previously calculated roll angle θ of the vehicle is equal to or larger than a threshold value S3. In step 330, if θ ≧ S3 is satisfied, it is determined that a rollover that requires deployment of the head-protecting airbag 26 on the passenger seat side has occurred in the vehicle, and then the process of step 334 is executed. Is done. In step 330, if θ ≧ S3 is not established, it is determined that the vehicle has not undergone a rollover in which the passenger-side head protection airbag 26 needs to be deployed, and the passenger-side head This routine ends without the protection airbag 26 being deployed.

On the other hand, at step 332, it is determined whether or not the previously calculated roll angle θ of the vehicle is equal to or greater than threshold value S4. In step 332, θ ≧ S4
Holds, the airbag 2 for protecting the head on the passenger side is provided.
It is determined that a rollover that needs to deploy 6 has occurred in the vehicle, and then the process of step 334 is performed. In step 332, if θ ≧ S4 is not established, it is determined that the vehicle has not undergone a rollover in which the passenger-side head-protecting airbag 26 needs to be deployed, and the passenger-side head This routine ends without the protection airbag 26 being deployed.

At step 334, it is determined whether or not the deployment of the head-protecting airbag 26 on the passenger seat side is prohibited by the cut-off switch 46 arranged on the instrument panel 48. In step 334, if the deployment of the passenger-side head protection airbag 26 is prohibited, the current routine ends without the passenger-side head protection airbag 26 being deployed. On the other hand, in step 334, the airbag 26 for protecting the head on the passenger seat side is used.
If is not prohibited, then step 336
Is performed.

At step 336, the switching element 1
56 and 164 are turned on, and the ignition of the squib 160 deploys the head protection airbag 26 on the passenger seat side. As a result, the head of the passenger in the passenger seat is properly protected. When the process of step 336 ends, the current routine ends. As described above, in the ignition control method in which the CPU 70 executes the routine shown in FIG. 7, when an occupant is present in the passenger seat, the threshold value S4 is applied. Therefore, when the vehicle in which the occupant is present in the passenger seat rolls over the roll angle S4 or more, the head protecting airbag 26 on the passenger seat side is deployed, and the head of the passenger in the passenger seat is appropriately protected. If no occupant is present in the passenger seat, a threshold value S3 larger than threshold value S4 is applied. Therefore,
In the case of a rollover of less than the roll angle S3 of a vehicle having no occupant in the front passenger seat, the head protection airbag 2 on the front passenger seat side is provided.
Unnecessary deployment of 6 is prevented. Furthermore, even when no occupant is present in the passenger seat, the airbag 26 for protecting the head on the passenger seat side is deployed when the vehicle rolls over the roll angle S3 or more. Therefore, when the driver moves to the passenger seat side with the rollover of the vehicle having the roll angle S3 or more, the driver is appropriately protected by the head protection airbag 26 on the passenger seat side.

In the routine of the third embodiment shown in FIG. 7, in addition to the presence / absence of an occupant in the front passenger seat, the routine of the second embodiment shown in FIG. The configuration may be such that the deployment timing of the head protection airbag 26 on the passenger seat side is changed according to the wearing situation. In step 306 of the routine shown in FIGS. 6 and 7, the roll angular velocity R is calculated based on the detection signal from the rollover sensor 30, and steps 204, 210, 310, 312, and 320 shown in FIGS. , 322, 3
30 and 332, the roll angular velocity R may be compared with the corresponding threshold values S1, S2, S3, and S4 instead of the roll angle θ. Also, a threshold value is set for each of the roll angle θ and the roll angular velocity R, and when one of the roll angle θ and the roll angular velocity R exceeds the set threshold value, the airbag for head protection is set. It is good also as composition which expands 24 and 26. Further, using a map 10 as shown in FIG. 8, the CPU 70 determines whether or not it is necessary for the CPU 70 to deploy the head protection airbags 24 and 26 from the positions of points on the map 10 determined from the roll angle θ and the roll angular velocity R. It is good also as a structure which judges. For example, if a rollover of the roll angle θ1 and the roll angular velocity R1 occurs after a frontal collision or a side collision of the vehicle, in the map 10 shown in FIG.
The point P1 indicating the rollover that has occurred is the threshold value S2
Beyond (S4), the head protection airbags 24 and 26 are within the deployment permission area A. Therefore, in this case, the CPU 70
Are airbags 24, 26 for protecting the head according to the roll direction.
Is developed.

In the above embodiment, the head protection airbags 24 and 26 correspond to the rollover occupant restraint device described in the claims, and the processes in step 200 and step 208 in FIG. It corresponds to the collision determination step and the threshold value setting step described in the claims. 6 correspond to the movement amount estimating step and the threshold value changing step described in the claims, and the processing in steps 308 and 318 in FIG. 6 correspond to the claims. The processing in steps 312 and 322 in FIG. 6 corresponds to the threshold setting step described in the claims. Further, the processing in step 328 of FIG. 7 corresponds to an occupant determination step described in the claims, and the processing in step 332 corresponds to a threshold setting step described in the claims.

[0084]

As described above, according to the first aspect of the present invention, when a rollover occurs immediately after a frontal collision or a side collision of a vehicle, the rollover occupant restraint device is used as a criterion for determining the operation. The threshold value is set to a smaller value than when there is no front collision or side collision of the vehicle. Therefore, when a rollover occurs after a frontal collision or a side collision of the vehicle, the occupant restraint device for rollover operates at a timing earlier than when rollover occurs alone. Therefore, even if a rollover occurs in a state where the occupant moves due to a frontal collision or a side collision of the vehicle, the occupant can be appropriately restrained without delaying the operation of the rollover occupant restraining device.

According to the second aspect of the present invention, the threshold value is changed in accordance with the amount of movement of the occupant following a collision of the vehicle. Therefore, when a rollover of the vehicle occurs, the rollover occupant restraint device operates at an appropriate timing according to the amount of movement of the occupant. Therefore, even if the occupant moves due to a vehicle collision or the like, the operation of the rollover occupant restraint device is not delayed, and the occupant can be appropriately restrained.

According to the third aspect of the present invention, when the occupant does not wear the seat belt, the threshold value is set to a smaller value than when the occupant wears the seat belt. You. Therefore, even if the occupant who does not wear the seat belt moves significantly in the vehicle due to the collision of the vehicle, the occupant restraint device for rollover operates at an early timing at the time of rollover, so that the occupant is appropriately restrained. be able to.

Further, according to the fourth aspect of the invention, when an occupant is present in the passenger seat, the threshold value is set to a smaller value than when no occupant is present in the passenger seat. For this reason, when the occupant is present in the passenger seat, the rollover occupant restraint device on the passenger seat side is operated at an earlier timing when the vehicle rolls over than when the occupant does not exist in the passenger seat. Therefore, it is possible to appropriately restrain the occupant in the passenger seat without delaying the operation of the rollover occupant restraint device. Further, even when the occupant does not exist in the passenger seat, the rollover occupant restraint device on the passenger seat side operates when the roll angle is equal to or larger than the predetermined value. Therefore, even if the driver moves to the passenger seat side with the rollover of the vehicle having a large roll angle, the driver can be appropriately restrained by the rollover occupant protection device on the passenger seat side.

[Brief description of the drawings]

FIG. 1 is a layout diagram in a vehicle of an ignition control system and an occupant protection device for implementing an ignition control method according to the present invention.

FIG. 2 is a perspective view of a deployed side collision airbag and a head protection airbag on the driver's seat side.

FIG. 3 is a circuit configuration diagram of an airbag control device provided in the ignition control system.

FIG. 4 is a circuit configuration diagram of an ignition circuit.

FIG. 5 is a flowchart illustrating a routine according to the first embodiment of the present invention.

FIG. 6 is a flowchart illustrating a routine according to a second embodiment of the present invention.

FIG. 7 is a flowchart illustrating a routine according to a third embodiment of the present invention.

FIG. 8 is a diagram showing a map for determining rollover.

[Explanation of symbols]

 12, 14 Front collision airbag 16, 18 Pretensioner 20, 22 Side collision airbag 24, 26 Head protection airbag 28 Airbag control device 30 Rollover sensor 32, 34 Side collision sensor 36, 38 Front collision sensor 40, 42 Seat belt wearing sensor 44 Seating sensor 46 Cutoff switch 66 Front and rear G sensor 68 Left and right G sensor 70 CPU 100 Ignition circuit

Claims (4)

[Claims] 1. An ignition control method for a vehicle occupant protection device that activates a rollover occupant restraint device when at least one of a roll angle and a roll angular velocity of a vehicle exceeds a predetermined threshold value. A collision determining step of determining whether or not a front collision or side collision has occurred; and when the vehicle has a front collision or side collision, the predetermined A threshold setting step of setting the threshold to a small value. 2. An ignition control method for a vehicle occupant protection device that activates a rollover occupant restraint device when at least one of a roll angle and a roll angular velocity of a vehicle exceeds a predetermined threshold value. And a threshold value changing step of changing the predetermined threshold value according to the estimated moving amount. . 3. The ignition control method for an occupant protection system for a vehicle according to claim 1, wherein the step of determining whether the occupant wears a seat belt includes the step of determining whether or not the occupant wears a seat belt. If not, a threshold setting step of setting the predetermined threshold to a smaller value than when the occupant wears a seat belt. 4. An ignition control method for an occupant protection system for a vehicle according to claim 1, wherein an occupant discriminating step of discriminating whether or not an occupant is present in a passenger seat; A threshold setting step of setting the predetermined threshold value for the rollover occupant restraint device on the passenger seat side to a small value as compared with a case where no occupant is present in the passenger seat. Ignition control method.