JP2002225672A - Deployment control system for vehicular air bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a deployment control system for a vehicular air bag that can protect an occupant more properly in consideration of an occupant movement amount in deployment control of an air bag. SOLUTION: A control unit part 23 controls the opening degree of a pressure reducing hole to an initial opening degree determined according to fastening or unfastening of a seat belt, a seat position and a seating position, until the occupant movement amount reaches a first given value, on the basis of detection results of a belt sensor 11, a position sensor 13, a seating sensor 15, a seat belt pull distance sensor 19 and a pressure sensor 21. The control unit part 23 controls the opening degree of the pressure reducing hole so that the internal pressure of the air bag changes according to a given pressure characteristic predetermined according to the occupant movement amount, until the occupant movement distance reaches a second given value from the first given value. The control unit part 23 controls the opening degree of the pressure reducing hole to a closed state thereof, when the occupant movement amount reaches the second given value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle airbag deployment control device.

[0002]

2. Description of the Related Art As a deployment control device for a vehicle airbag of this type, for example, a device disclosed in Japanese Patent Application Laid-Open No. 10-35405 is known. This vehicle airbag deployment control device is provided with a decompression hole for releasing gas generated from the gas generator to the outside in a case that accommodates the gas generator and the folded airbag, and adjusts the opening degree of the decompression hole. An actuator that operates a valve that operates the valve, a controller that operates the actuator in accordance with a signal of a temperature sensor that detects a vehicle interior temperature and a signal of a seating sensor that detects a seating position of an occupant, and variably controls the opening degree of the pressure reducing hole. It has. Thus, regardless of the temperature condition of the gas generator, the opening degree of the pressure reducing hole is appropriately controlled so that the gas pressure for inflating the airbag is within a normal range, and the opening degree of the pressure reducing hole is adjusted according to the seating position of the occupant. Therefore, the gas pressure for inflating the airbag is appropriately controlled so that the airbag always hits the occupant softly.

[0003]

SUMMARY OF THE INVENTION The present inventors have conducted intensive studies on the deployment control of the airbag which can more appropriately protect the occupant. It was newly found that it is necessary to consider not only the seating position but also the amount of movement of the occupant (head) in front of the vehicle (occupant movement) due to the collision of the vehicle (frontal collision).

An object of the present invention is to provide a vehicle airbag deployment control device which can more appropriately protect a passenger in consideration of the amount of movement of the passenger in the deployment control of the airbag. is there.

[0005]

According to a first aspect of the present invention, there is provided a vehicle airbag deployment control device, wherein a case for accommodating the gas generator and the folded airbag has a pressure reducing hole for releasing gas generated from the gas generator to the outside. A vehicle airbag provided with a valve for adjusting the opening of the pressure reducing hole, an actuator for driving the valve, and a pressure reducing hole opening control means for driving the actuator to control the opening of the pressure reducing hole. Deployment control device, comprising: a wearing state detecting means for detecting whether or not the occupant is wearing a seat belt; a seat position detecting means for detecting a seat position in a vehicle longitudinal direction; and detecting a seating position of the occupant. Seating position detecting means, occupant moving amount detecting means for detecting an occupant moving amount in front of the vehicle, and airbag internal pressure detecting means for detecting pressure in the airbag. The pressure-reducing hole opening degree control means detects whether or not the seat belt is worn detected by the wearing state detection means, the seat position detected by the seat position detection means, and the seat position detected by the seating position detection means. Sitting position,
Based on the occupant movement detected by the occupant movement detection means and the pressure detected by the airbag internal pressure detection means,
Until the movement amount of the occupant at the time of collision of the vehicle reaches the first predetermined value, the pressure reducing hole is set to have the initial opening determined according to the presence or absence of the seat belt, the seat position and the seating position. The opening degree is controlled.

According to the vehicle airbag deployment control device of the present invention, the occupant starts moving forward due to the collision of the vehicle, and the seatbelt does not move until the occupant movement amount reaches the first predetermined value. The opening degree of the pressure reducing hole is controlled so as to be the initial opening degree determined in accordance with the presence / absence of wearing, the seat position and the sitting position. Thereby, the gas pressure for inflating the airbag is adjusted according to the seating state of the occupant, and the drag of the airbag when the occupant (head) comes into contact with the airbag is appropriately controlled, so that the occupant is appropriately controlled. (Head) can be prevented from being applied with excessive pressing force.

According to a second aspect of the present invention, there is provided the vehicle airbag deployment control device, wherein the pressure reducing hole opening control means further controls the air pressure until the occupant movement amount reaches the second predetermined value from the first predetermined value. The opening degree of the pressure reducing hole is controlled so that the pressure in the bag changes according to a predetermined pressure characteristic determined in advance according to the occupant movement amount.

According to the vehicle airbag deployment control device of the second aspect, the occupant moves forward until the occupant travels from the first predetermined value to the second predetermined value.
The opening degree of the pressure reducing hole is controlled such that the pressure in the airbag changes according to a predetermined pressure characteristic determined in advance according to the occupant movement amount. Thus, the drag of the airbag is appropriately controlled according to the occupant movement amount, and the occupant (head) can be decelerated at a desired deceleration.

According to a third aspect of the present invention, in the vehicle airbag deployment control device, the pressure reducing hole is closed when the occupant movement further reaches a second predetermined value. The opening degree of the pressure reducing hole is controlled.

According to the third aspect of the present invention, the opening degree of the pressure reducing hole is controlled so that the pressure reducing hole is closed when the occupant movement amount reaches the second predetermined value. Is done. As a result, a predetermined gas pressure is maintained in the airbag, and it is possible to reliably prevent the occupant (head) from colliding with a vehicle-side member (a steering wheel, an instrument panel, or the like). As a result, at the time of a vehicle collision, the occupant can be more appropriately protected.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a vehicle airbag deployment control device according to the present invention will be described with reference to the drawings. In the description of the drawings, the same elements will be denoted by the same reference symbols, without redundant description.

FIG. 1 is a block diagram showing a configuration of a vehicle airbag deployment control device according to the present embodiment. The vehicle airbag deployment control device controls the deployment of the airbag in the vehicle airbag device 1, and includes a belt sensor 11 and a position sensor 13.
A seat sensor 15, a G sensor 17, a seat belt withdrawal amount sensor 19, a pressure sensor 21, and a control unit 23 for controlling the deployment state of an airbag included in the vehicle airbag device 1. Have. The belt sensor 11 is detection means (wearing state detection means) for detecting whether or not the occupant is wearing a seat belt. The position sensor 13 is detection means (seat position detection means) for detecting a seat position (seat slide position) in the vehicle front-rear direction. The seat sensor 15 is a detecting means (seating position detecting means) for detecting a seating position of the occupant in the seat. The G sensor 17 is detection means for detecting a deceleration acting on the vehicle (vehicle body).
The seat belt withdrawal amount sensor 19 is a detecting means (occupant moving amount detecting means) for detecting the moving amount (occupant moving amount) of the occupant (head) seated on the seat in front of the vehicle. The pressure sensor 21 detects the pressure (gas pressure) in the airbag.
Detecting means for detecting air pressure (air bag internal pressure detecting means)
It is.

Belt sensor 11, position sensor 1
3, the seat sensor 15, the G sensor 17, the seat belt withdrawal amount sensor 19, and the pressure sensor 21 are connected to the control unit 23. Each sensor 11, 13, 15, 1
The detection results at 7, 19, and 21 indicate that the sensors 11, 1
3, 15, 17, 19, and 21 are input to the control unit 23 as output signals. As the seat sensor 15, for example, a radar, an ultrasonic sensor, an image recognition device, or the like is used to detect the position of the seated occupant (for example, the upper body position including the head). The control unit 23
Is connected to the gas generator 3 and the actuator 8 of the vehicle airbag device 1 and outputs a control signal to the gas generator 3 and the actuator 8.

The control unit 23 has a central processing unit (CPU) 25, a ROM 27, a RAM 29, and the like. The CPU 25 is a processing unit that performs signal processing and the like of the entire control unit 23. The ROM 27 is a storage unit that stores a control program for controlling the control unit 23 (CPU 25) and the like. The RAM 29 is a CPU 2
The results of the various calculations in 5 are temporarily stored in a readable manner. The CPU 25 (control unit unit 23) stores a control program for an airbag deployment control process described later in R
By reading from the OM 27 and performing processing in accordance with this control program, it functions as a pressure-reducing hole opening degree control means.

Next, the configuration of the vehicle airbag device 1 will be described with reference to FIG. FIG. 2 is a schematic sectional view showing a configuration of the vehicle airbag device according to the embodiment of the present invention.

The vehicle airbag device 1 has a case 2 having a substantially U-shaped cross section with an open upper part, a gas generator (inflator) 3 housed in the case 2, and a state folded in the case 2. Airbag 4 stored in
And a lid 5 for closing the upper opening of the case 2.

The vehicle airbag device 1 is attached to the center of the steering wheel for the driver, and is attached to the instrument panel in front of the passenger seat for the passenger in the passenger seat. In the airbag device 1 for a vehicle, the gas generator 3 operates, and the airbag 4 inflates the lid 5 by pushing and opening the lid 5 with the generated gas, and inflates the head and upper body of the occupant who falls forward.
It is supposed to be received at. The lid 5 is provided with a break 5a. When the airbag 4 is inflated by the gas generated by the gas generator 3, the lid 5 breaks from the break portion 5a due to the pressure, and the lid 5 rotates upward around the front edge and opens. Will expand and deploy. The means for opening the lid 5 during operation of the vehicle airbag device 1 is not limited to the configuration in which the broken portion 5a is provided in the lid 5;
A known configuration can be adopted, such as a configuration in which the pin 5b for fixing the internal pressure to a shear pin that shears when the internal pressure exceeds a set value.

The case 2 is provided with a pressure reducing hole 6 for allowing a part of the gas generated from the gas generator 3 to escape to the outside of the case 2. The pressure reducing hole 6 is provided with a valve 7 for adjusting the opening degree. Decompression hole 6 by valve 7
The pressure (gas pressure) in the airbag 4 can be controlled by adjusting the opening of the airbag 4. This valve 7
Is connected to an actuator 8, and the valve 7 is driven by the actuator 8.

As shown in FIG. 1, the gas generator 3 is connected to a control unit 23, and its operation state is controlled based on a control signal sent from the control unit 23. The control unit 23
Based on the deceleration detected by the sensor 17, it is determined whether or not the vehicle is in a collision state, and a control signal is output so as to operate the gas generator 3 at the time of a vehicle collision. Thereby, the gas generator 3 operates and the airbag 4 is deployed. The actuator 8 is also connected to the control unit 23 as in the case of the gas generator 3, and its operating state is controlled based on a control signal sent from the control unit 23.

Next, referring to FIG.
3 (CPU 25) will be described. This airbag deployment control processing operation is executed based on a control program stored in the ROM 27.

The control unit 23 (CPU 25) controls the sensors 11, 13, 15, 17, 1 at predetermined cycles.
The output from 9, 21 is read. First, when the processing operation is started, the control unit 23 determines whether or not the seat belt is worn, the seat position and the seating position based on output signals from the belt sensor 11, the position sensor 13 and the seating sensor 15 in S10. The corresponding initial opening of the pressure reducing hole 6 is determined. For example, when the seat belt is worn, the seat position is a position closer to the front, and the occupant is seated shallowly in the seat (a position closer to the front), the initial opening of the pressure reducing hole 6 is set to a large value. Is done. On the other hand, when the seat belt is not worn, the seat position is at the rearward position, and the occupant is seated deeply in the seat (rearward position), the initial opening degree of the pressure reducing hole 6 becomes a small value. Is set. In S10, the control unit 23 outputs a control signal to the actuator 8 so that the opening of the pressure reducing hole 6 becomes the determined initial opening.

Next, at S11, the control unit 23
Determines whether the occupant movement amount has reached the first predetermined value (XX1) based on the output signal from the seat belt withdrawal amount sensor 19. Here, the occupant movement amount will be described with reference to FIG. The distance from the predetermined reference position X0 to the occupant (head) P sitting on the seat S is “X”.
Similarly, the distance from the predetermined reference position X0 to a position slightly closer to the occupant P from the tip of the airbag 4 (the portion where the occupant (head) hits) when the airbag 4 is fully deployed is represented by “X1”. " The distance from the predetermined reference position X0 to a position slightly closer to the occupant P from the instrument panel I is defined as “X2”. Accordingly, in S11, the occupant (head) P
Is moved forward of the vehicle, and it is determined whether or not the occupant (head) P has moved to a position immediately before hitting the airbag 4 in the fully deployed state. In FIG. 4, the description has been given based on the positional relationship between the airbag 4 and the instrument panel I with respect to the occupant P seated on the front passenger seat. By replacing
The same can be defined.

If the occupant movement amount has reached the first predetermined value (X-X1) ("YES" in S11), the process proceeds to S12, where the control unit unit 23 Thus, the opening degree of the pressure reducing hole 6 is determined so that the pressure in the airbag 4 changes according to a predetermined pressure characteristic determined in advance in accordance with the occupant movement amount. In this pressure characteristic, a target value of the pressure in the airbag 4 is set for the occupant movement amount, and is stored in the ROM 27 in the form of a map or the like. The pressure characteristic is, for example, as shown in FIG.
The pressure in the airbag 4 is set so as to gradually decrease while the occupant movement amount changes from the first predetermined value (XX1) to the second predetermined value (XX2). The pressure characteristics can be changed in inclination or the like as appropriate.

The control unit 23 stores the target value of the pressure in the airbag 4 corresponding to the current occupant movement amount in the ROM 27.
The opening degree of the pressure reducing hole 6 is determined such that the pressure in the airbag 4 detected by the pressure sensor 21 matches the target value, and the opening degree of the pressure reducing hole 6 is determined. The control signal is output to the actuator 8 so that the opening degree becomes the adjusted opening degree. Thus, the opening degree of the pressure reducing hole 6 is feedback-controlled based on the pressure in the airbag 4. On the other hand, the occupant movement amount is equal to the first predetermined value (X-
If X1) has not been reached ("NO" in S11),
Returning to S10, the opening of the pressure reducing hole 6 is set to the above-mentioned initial opening.

At S13, the control unit 23
Based on the output signal from the seat belt withdrawal amount sensor 19, it is determined whether or not the occupant movement amount has reached the second predetermined value (X-X2), that is, the occupant (head) P is in the instrument panel I.
It is determined whether or not it has moved to the position immediately before hitting.

If the occupant movement amount has reached the second predetermined value (X-X2) ("YES" in S13), the process proceeds to S14, where the control unit 23 closes the opening of the pressure reducing hole 6 to the closed state. And outputs a control signal to the actuator 8 so that the valve 7 closes the pressure reducing hole 6. On the other hand, if the occupant movement amount has not reached the second predetermined value (X-X2) ("NO" in S13), the process returns to S12, and the feedback control of the opening degree of the pressure reducing hole 6 is continued. Will be.

In this embodiment, when the vehicle collides, the deceleration of the vehicle body is generally small in the initial stage and large in the latter half of the collision, so that the deceleration of the occupant also increases in the latter half of the collision. The opening of the hole 6 is controlled. Therefore, the opening degree of the pressure reducing hole 6 is reduced as the deceleration of the vehicle body decreases, and the opening degree of the pressure reducing hole 6 is increased as the deceleration of the vehicle body increases. The opening degree of the hole 6 is reduced, and the drag of the airbag 4 is increased. Then, in the latter half of the collision when the deceleration becomes large, the opening degree of the pressure reducing hole 6 becomes large and the drag of the airbag 4 becomes small. Thus, the occupant can be decelerated at a substantially constant deceleration, and the occupant can be properly protected.

As described above, in the vehicle airbag deployment control device according to the present embodiment, the occupant P starts to move forward due to the collision of the vehicle, and the occupant movement amount becomes the first predetermined value (X-X1). ) Until the control unit 23
Accordingly, the opening degree of the pressure reducing hole 6 is controlled so as to be the initial opening degree determined in accordance with the presence or absence of the seat belt, the seat position and the seating position. Therefore, the occupant P
The gas pressure for inflation of the airbag 4 is adjusted in accordance with the seating state of the occupant, and the drag of the airbag 4 when the occupant (head) P contacts the airbag 4 is appropriately controlled,
Applying an excessive pressing force to the occupant (head) P can be prevented.

Further, while the occupant P moves further forward and the occupant movement amount reaches the second predetermined value (XX2) from the first predetermined value (XX1), the control unit 23 Accordingly, the opening degree of the pressure reducing hole 6, that is, the amount of generated gas flowing out from the gas generator 3 is controlled so that the pressure in the airbag 4 changes according to a predetermined pressure characteristic predetermined according to the occupant movement amount. Will be done. Therefore, the drag of the airbag 4 is appropriately controlled according to the occupant movement amount, and the occupant (head) P can be decelerated at a desired deceleration.

Then, the occupant movement amount becomes the second predetermined value (X-
When X2) is reached, the opening of the pressure reducing hole 6 is controlled by the control unit 23 so that the pressure reducing hole 6 is closed. For this reason, a predetermined gas pressure is maintained in the airbag 4, and the occupant (head) P is mounted on the vehicle side member (the steering wheel, the instrument panel I).
) Can be reliably prevented.

As a result, according to the vehicle airbag deployment control device of the present embodiment, it is possible to consider the occupant movement amount in the deployment control of the airbag 4, and to control the vehicle in the event of a vehicle collision. Thus, the occupant P can be more appropriately protected.

The present invention is not limited to the above embodiment. For example, a first predetermined value (XX1)
Also, the second predetermined value (XX2) can be appropriately changed and set.

In the present embodiment, the pressure sensor 21 is used as the airbag internal pressure detecting means.
Instead of using the pressure sensor 21, an outflow amount sensor that detects the amount of generated gas flowing out of the case 2 through the pressure reducing hole 6 may be used.

Further, in this embodiment, the seat belt withdrawal amount sensor 19 is used as the occupant movement amount detecting means. Instead of the seat belt withdrawal amount sensor 19, a radar, an ultrasonic sensor, or an image recognition device is used. It is also possible to detect how much the occupant (head) P has moved from the position before the collision by using the seating sensor 15. In this case, the seating sensor 15 functions as the occupant movement amount detecting means and the seating position detecting means, so that the number of sensors (detecting means) can be reduced and the cost of the system can be reduced.

[0035]

According to the vehicle airbag deployment control apparatus of the present invention, the pressure reducing hole opening degree control means determines whether or not the seat belt is detected by the wearing state detection means and whether the seat position is detected. Based on the detected seat position, the seating position detected by the seating position detection means, the occupant movement detected by the occupant movement detection means, and the pressure detected by the airbag internal pressure detection means. Until the amount of movement of the occupant when the vehicle collides reaches the first predetermined value, the pressure is reduced so that the initial opening determined according to the presence or absence of the seat belt, the seat position and the seating position is determined. The pressure in the airbag is controlled in accordance with the occupant movement amount until the occupant movement amount reaches the second predetermined value from the first predetermined value by controlling the opening degree of the hole. The degree of opening of the decompression hole varies according to When the occupant movement amount reaches the second predetermined value, the opening degree of the pressure reduction hole is controlled so that the pressure reduction hole is closed, so that the occupant movement amount is considered for the airbag deployment control. As a result, the occupant can be more properly protected.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a vehicle airbag deployment control device according to an embodiment of the present invention.

FIG. 2 is a schematic sectional view showing a configuration of a vehicle airbag device according to an embodiment of the present invention.

FIG. 3 is a flowchart for explaining an airbag deployment control processing operation executed by a pressure reducing hole opening degree control unit included in the vehicle airbag deployment control device according to the embodiment of the present invention.

FIG. 4 is an explanatory diagram showing a positional relationship between an airbag, an instrument panel, and an occupant.

FIG. 5 is a diagram showing pressure characteristics in an airbag.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Airbag apparatus for vehicles, 2 ... Case, 3 ... Gas generator, 4 ... Airbag, 6 ... Decompression hole, 7 ... Valve,
8 Actuator, 11 Belt sensor, 13 Position sensor, 15 Seating sensor, 17 G sensor, 1
9: Seat belt withdrawal amount sensor, 21: Pressure sensor, 2
3 ... Control unit, I ... Instrument panel, P
... crew, S ... seat.

Claims (3)

[Claims] 1. A case accommodating a gas generator and a folded airbag, wherein a decompression hole for releasing gas generated from the gas generator to the outside is provided; a valve for adjusting an opening degree of the decompression hole; An airbag deployment control device for a vehicle, comprising: an actuator that drives a valve; and a pressure-reducing hole opening control unit that drives the actuator to control the degree of opening of the pressure-reducing hole. Wearing state detecting means for detecting whether or not the vehicle is occupied; seat position detecting means for detecting a seat position in the longitudinal direction of the vehicle; seating position detecting means for detecting a seating position of the occupant; And an airbag internal pressure detecting means for detecting a pressure in the airbag, wherein the pressure-reducing hole opening degree control is provided. The means includes presence / absence of the seat belt detected by the wearing state detecting means, the seat position detected by the seat position detecting means, and the seating position detected by the seating position detecting means. And the occupant movement detected by the occupant movement detection means,
Based on the pressure detected by the airbag internal pressure detecting means, whether or not the seat belt is worn, until the occupant movement amount at the time of a vehicle collision reaches a first predetermined value; A deployment control device for an airbag for a vehicle, wherein an opening degree of the pressure reducing hole is controlled so as to have an initial opening degree determined according to a position and the seating position. 2. The pressure-reducing hole opening control means further includes a step of controlling the pressure in the airbag until the occupant movement amount reaches the second predetermined value from the first predetermined value. 2. The deployment control device for a vehicle airbag according to claim 1, wherein the degree of opening of the pressure reducing hole is controlled so as to change in accordance with a predetermined pressure characteristic which is predetermined according to the amount. 3. The pressure reducing hole opening control means further controls the opening of the pressure reducing hole such that the pressure reducing hole is closed when the occupant movement amount reaches the second predetermined value. The vehicle airbag deployment control device according to claim 2, wherein: