JPH0920206A - Vehicle occupant protection system - Google Patents

Abstract

(57) [Summary] [Purpose] To improve the occupant protection function while extending the battery life as much as possible. A collision of a vehicle is detected by operating on the basis of electric energy supplied from a battery 10, and an inflator 7 that rapidly supplies high-pressure gas to the airbag 6 to rapidly expand the airbag 6 is energized. In the vehicle occupant protection device having the vehicle collision detection means 12, the occupant presence detection means (pyroelectric infrared sensor) 111 for detecting whether or not an occupant exists in the vehicle, and the occupant presence detection means 111. Is detected, the battery 10 is controlled to be supplied to the vehicle collision detection means 12, and if the presence of an occupant is not detected,
Control means (11, 113) for controlling to stop the supply of electric power from the battery 10 to the vehicle collision detection means 12.
Etc.) and.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle occupant protection device for protecting an occupant of a vehicle when the vehicle collides.

[0002]

2. Description of the Related Art Generally, a so-called airbag that can be instantly inflated is used to protect an occupant in the event of a vehicle collision. A protective device using this airbag is usually modularized and can be attached to and detached from a steering wheel. Installed on.

In this type of protection device, when a collision occurs and the vehicle deceleration increases above a certain value, the inflator is controlled to rapidly supply high-pressure gas to the airbag, and the inflator and the like are also controlled. A method of using a battery is known as an energy source for driving.

In such a vehicle occupant protection device, a battery is driven as an energy source, but the vehicle occupant protection device is an important device for protecting an occupant, and functions for battery life when necessary. I don't want to stop doing it. Therefore,
As a technique for extending the battery life as much as possible, for example,
The technique described in Japanese Patent Laid-Open No. 6-16105 is known.

In the technique of the above publication, it is determined whether or not the vehicle is in use by detecting the rotation of the rotating shaft of the steering wheel, and when the vehicle is in use and after entering the non-use state. The vehicle occupant protection device is held in an operable state only for a certain period of time.

[0006]

However, in the technique disclosed in the above publication, the operable state of the vehicle occupant protection device is controlled by the use state of the vehicle determined based on the rotation detection of the rotating shaft of the steering wheel. So, for example, if you are parked on the shoulder and the occupant is taking a break,
Even if another vehicle collides, the rotation of the rotary shaft is not detected for a long time, so that the vehicle occupant protection device is not in an operable state, and the vehicle occupant protection device does not function. I was afraid.

The present invention has been made under such a background, and an object thereof is to extend battery life as much as possible.
It is to improve the passenger protection function.

[0008]

In order to achieve the above object, the present invention detects the collision of a vehicle by operating on the basis of the electric power supplied from a battery and uses the air to inflate the airbag rapidly. In a vehicle occupant protection device having vehicle collision detection means for energizing an inflator that rapidly supplies high-pressure gas to a bag, an occupant presence detection means for detecting whether or not an occupant is present in the vehicle, and the occupant presence detection means. When the presence of an occupant is detected by the, the battery is controlled so that power is supplied to the vehicle collision detection means, and when the presence of an occupant is not detected, the battery is transferred to the vehicle collision detection means. And a control means for controlling so as to stop the supply of electric power.

Therefore, for example, when the occupant is resting while parked on the road shoulder, the vehicle occupant protection device will not be inoperable, and the occupant protection function is improved. Further, when the presence of an occupant is not detected, the power supply from the battery to the vehicle collision detection means is stopped to save power, so that the battery life can be extended.

[0010]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing the vicinity of a steering wheel to which a vehicle occupant protection system according to an embodiment of the present invention is mounted.

In FIG. 1, a rotating shaft 3 rotatably housed in a sheath 2 is attached to the center of a steering wheel 1, and a connecting portion between the steering wheel 1 and the rotating shaft 3 is provided with an upper lining 4. A lower lining 5 is provided.

In a space surrounded by the upper lining 4 and the steering wheel 1, an air bag 6 and an inflator 7 capable of instantaneously supplying high pressure gas to the air bag 6.
Is stored. Further, in the space surrounded by the lower lining 5 and the steering wheel 1, a module 8 of an energization timing control circuit for electrically controlling the ignition timing of the gas to be supplied to the inflator 7 is housed.

The energization timing control circuit module 8
Is a module case 9 pre-mounted in a space surrounded by the lower lining 5 and the steering wheel 1.
In addition, it can be detachably attached.

FIG. 2 is a circuit diagram of the energization timing control circuit (energization timing control circuit module 8), which is roughly divided into a battery 10 as a power supply source for the circuit, a power supply control section 11, and a collision. It is composed of the detection unit 12.

The battery 10 has, for example, a lithium / thionyl chloride battery and the like, has heat resistance to a temperature predominant in a space surrounded by the lower lining 5 and the steering wheel 1, and is constant over the entire life period. It is preferably a battery that maintains an output voltage.

The power supply control unit 11 comprises a pyroelectric infrared sensor 111 for detecting the presence or absence of an occupant, a time extension circuit 112, and a supply switch circuit 113.
The pyroelectric infrared sensor 111 generates a voltage only when there is a temperature change due to infrared rays emitted from the human body or the like. The time extension circuit 112 is composed of a CR time constant circuit, and the supply switch circuit 113 is composed of an FET 113a, a transistor 113b, and resistors 113c and 113d.

The collision detection unit 12 is composed of an impact sensor, and it is preferable that the impact sensor is a passive impact sensor that consumes no electric power except during operation in consideration of power saving.

Next, the operation of the energization timing control circuit 8 will be described.

Once the presence of an occupant is detected by the pyroelectric infrared sensor 111, the time extension circuit 112
High voltage is applied to the gate electrode of the FET 113a for a certain period of time, the FET 113a is turned on for a certain period of time, and the transistor 113b is also turned on. Therefore, the collision detection unit 12 is supplied with electric power from the battery 10, and The passenger occupant protection device becomes operable.

When a collision is detected by the collision detector 12 in this operable state, the collision detector 12
The resistor for igniting the explosive in the inflator 7 is energized from the inflator 7, and the high pressure gas is instantaneously supplied from the inflator 7 to the airbag 6 due to the explosion of the explosive, so that the airbag 6 is rapidly inflated. It avoids a direct crash into.

As described above, in this embodiment, the pyroelectric infrared sensor 111 detects the presence of an occupant, and when the presence of the occupant is detected, the collision detection unit 12 from the battery 10 is always informed. When the presence of an occupant is not detected by supplying electric power to the vehicle occupant protection device, the power supply from the battery 10 to the collision detection unit 12 is stopped to protect the occupant of the vehicle. The device is inoperable.

Therefore, unlike the conventional case, the occupant protection device for a vehicle does not become inoperable when the occupant is resting while parked on the road shoulder, and the occupant protection function is improved. If the presence of a passenger is not detected,
Since the power supply from the battery to the collision detection unit is stopped to save power, the battery life can be extended.

It should be noted that the present invention is not limited to the above-described embodiment, and for example, as an occupant detection sensor, a pyroelectric such as a flat switch provided in a driver's seat or the like and turned on by a load when the occupant is seated. A sensor other than the infrared sensor may be used. Further, the vehicle occupant protection device, particularly the airbag, can be installed at a place other than the steering wheel, for example, at a predetermined position in front of the passenger seat or the rear seat to protect occupants other than the driver.

[0025]

As described above, according to the present invention,
A vehicle having vehicle collision detection means for detecting a vehicle collision by operating on the basis of electric power supplied from a battery and energizing an inflator that rapidly supplies high-pressure gas to the airbag in order to rapidly inflate the airbag. In an occupant protection device for passengers, occupant presence detecting means for detecting whether or not an occupant is present in a vehicle, and when the presence of an occupant is detected by the occupant presence detecting means, the vehicle collision detecting means from the battery. Control means for controlling to stop the supply of electric power from the battery to the vehicle collision detection means when the presence of an occupant is not detected. When the occupant is parked on the shoulder of the road and the occupant is taking a break, the occupant protection device for the vehicle does not become inoperative, and the occupant protection function is improved. Further, when the presence of an occupant is not detected, the power supply from the battery to the vehicle collision detection means is stopped to save power, so that the battery life can be extended.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing the vicinity of a steering wheel to which a vehicle occupant protection device according to an embodiment of the present invention is attached.

FIG. 2 is a diagram showing a circuit configuration of a vehicle occupant protection device according to an exemplary embodiment of the present invention, in particular, an energization timing control circuit.

[Explanation of symbols]

 6 ... Airbag 7 ... Inflator 8 ... Energization timing control circuit 10 ... Battery 11 ... Electric power supply control unit 12 ... Collision detection unit 111 ... Pyroelectric infrared sensor 113 ... Supply switch circuit

Claims (1)

[Claims] 1. A vehicle collision in which a vehicle collision is detected by operating on the basis of electric power supplied from a battery, and an inflator that rapidly supplies high-pressure gas to the airbag to rapidly inflate the airbag is energized. In a vehicle occupant protection device having a detecting means, an occupant presence detecting means for detecting whether or not an occupant is present in the vehicle, and when the presence of the occupant is detected by the occupant presence detecting means, from the battery. Controlling so that electric power is supplied to the vehicle collision detection means, and when the presence of an occupant is not detected, control means for controlling the supply of electric power from the battery to the vehicle collision detection means, An occupant protection device for a vehicle, comprising: