JPH05221282A - Vehicle quick deceleration condition detecting device - Google Patents

Abstract

PURPOSE:To surely detect a vehicle quick deceleration condition in a very short time by providing a distortion detecting means in a side impact beam inward of a door panel. CONSTITUTION:A strain gage 26 is pasted to a surface (surface inside cabin) in a side of an inner panel 16 of a side impact beam 20 in a front door 12 of a vehicle, to detect distortion of the side impact beam 20. The strain gage 26 is connected to an air bag device through an action circuit, and when the vehicle reaches a quick deceleration condition to generate distortion in the side impact beam 20, the air bag device is actuated. Since the side impact beam 20 has high rigidity, the vehicle quick deceleration condition can be surely detected in a very short time with no influence by an unnecessary repeated load and low load, and further smallness in size and lightness in weight can be also attained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle rapid deceleration state detection device for detecting a vehicle rapid deceleration state and operating an occupant protection device such as an airbag device.

[0002]

2. Description of the Related Art Conventionally, when a load of a predetermined value or more is applied to the outer surface (door outer panel) of a vehicle door, the door outer panel may be deformed toward the interior side. It has been proposed to provide a side impact beam made of steel pipe or the like inside a vehicle door. The side impact beam increases the rigidity of the vehicle door as a whole, and suppresses the amount of deformation of the door when a high load is applied during a side collision of the vehicle, for example, to protect the occupant.

By the way, in addition to such a side impact beam, a vehicle equipped with an occupant protection device at the time of a vehicle collision, for example, an airbag device which detects a vehicle collision state and bulges the back toward the occupant side has already been available. is there. This type of air bag device is generally installed near the steering wheel of a vehicle or the upper part of a glove box, but in recent years it has been proposed to install the air bag device on a vehicle door. .. Along with this, a sensor for operating the airbag device disposed inside the vehicle door is required.

As such a sensor, it is conceivable to use an existing sensor of the airbag device provided on a steering wheel or the like. However,
Since such an existing sensor is generally configured to detect a sudden deceleration state of the vehicle at the time of a collision by using a combination of an inertial mass body and a spring (a so-called spring-mass system), an extremely short time is required. Detecting acceleration based on extremely small displacement (eg, several millimeters) within (eg, several milliseconds / second), that is, ON / OFF set in the sensor.
It was difficult to satisfy each of the OFF conditions. In other words, there is a drawback that a circuit or the like for determining a predetermined continuation of the acceleration applied when the vehicle is rapidly decelerated becomes complicated.

On the other hand, there is also proposed a sensor for detecting a mechanical deformation (displacement) of a member such as a door outer panel due to a rapid deceleration state of a vehicle at the time of collision to detect the mechanical deformation (displacement) and actuating an air bag device or the like ( For example, JP-A-48-
12072). In this type of sensor, the amount of mechanical deformation of a member that buckles due to the impact force at the time of sudden deceleration of the vehicle is measured, and the measured value is compared with a reference value to detect the sudden deceleration state of the vehicle at the time of a collision. Therefore, even if the amount of mechanical deformation of the buckling member does not reach the reference value by one impact force, a small impact force is repeatedly applied (in other words, a small buckling deformation). Due to the accumulated amount), the reference value may be reached. Therefore, in such a case, the function as the original sensor cannot be exerted.

Further, in the sensor for detecting the vehicle rapid deceleration state based on such mechanical deformation (displacement), the period until the airbag device or the like is substantially operated after the sensor detects the vehicle rapid deceleration state. The sensor must be maintained in a state where it can perform its original function without being destroyed. Therefore, it is necessary to make the structure of the sensor itself robust, which makes it difficult to reduce the size and weight.

Further, in the sensor for detecting the rapid deceleration state of the vehicle based on the mechanical deformation, regardless of whether the member such as the door outer panel is partially or totally deformed, in other words, the door outer panel or the like is deformed. To ensure that any part of the member is deformed can be detected,
It is necessary to arrange the sensor over the entire area of the door outer panel. Therefore, there are problems that the number of parts is increased, the assembling property is deteriorated, and the sensor arrangement space is limited.

[0008]

SUMMARY OF THE INVENTION In consideration of the above facts, the present invention reliably detects a sudden deceleration state of a vehicle in an extremely short time without being affected by unnecessary repeated load or low acceleration (low load). It is an object of the present invention to obtain a vehicle rapid deceleration state detection device that can be made compact and lightweight.

[0009]

A vehicle sudden deceleration state detecting device according to the present invention is applied to a vehicle door in which a side impact beam is arranged inside a door panel, and detects a vehicle sudden deceleration state to detect a vehicle sudden deceleration state. A vehicle sudden deceleration state detection device for operating an occupant protection device provided in the vehicle, wherein the side impact beam is provided with a strain detection means capable of detecting a strain of the side impact beam.

[0010]

In the vehicle sudden deceleration state detecting device having the above structure, when the vehicle reaches the rapid deceleration state and a high load of a predetermined value or more acts on the door panel and the side impact beam is distorted,
This is detected by the strain detecting means without delay.

In this case, the side impact beam is arranged inside the door panel and is distorted by a load acting on any part of the door panel. Therefore, the strain detecting means provided on the side impact beam can instantly detect a high load acting on any part of the door panel. In other words, a high load acting on any part of the door panel can be instantly detected with only a single strain detecting means. Therefore, unlike the conventional detection device, the number of parts for detecting the vehicle sudden deceleration state does not increase, the assembling property does not deteriorate, and the arrangement space is not limited.

Further, the side impact beam itself has a high rigidity, has a small strain when a low load is applied, and a large strain when a high load is applied. It is easy to determine whether a low load that does not require operation of the occupant protection device has been applied or a high load that originally requires operation of the occupant protection device has been applied.

[0013]

1 is a perspective view of a front door 12 of a vehicle to which a vehicle rapid deceleration state detection device 10 according to an embodiment of the present invention is applied. Further, in FIG. 2, the front door 1
2 is a schematic cross-sectional view of FIG. 2, and FIG.
A cross-sectional view of the front door 12 is shown along the line.
Further, FIG. 4 shows an enlarged view of a main part of the front door 12 (FIG. 2), and FIG. 5 shows an enlarged cross-sectional view of the main part of the front door 12 taken along line 5-5 of FIG. ing.

An arrow FR is shown in each drawing as appropriate.
Indicates the vehicle front side, arrow UP indicates the vehicle upper side, and arrow IN indicates the vehicle interior side.

The front door 12 is provided with an outer panel 14 and an inner panel 16 as door panels, and the outer panel 14 and the inner panel 16 form a space 18 inside the door.

A side impact beam 20 is arranged in the interior space 18 of the door. The side impact beam 20 is a high-rigidity strength member that is a pipe-shaped elongated body having a rectangular cross section, and is inside the front door 12 (the space 1 in the door).
8), it is arranged along the vehicle front-rear direction, and as shown in detail in FIGS. 4 and 5, both longitudinal ends thereof are attached to the shelf portions 22 provided at the vehicle front-rear end portions of the inner panel 16 via brackets 24. Installed. The shelf 22 and the bracket 24 of the inner panel 16 are naturally made highly rigid, and therefore, the side impact beam 20 is firmly fixed and the fixed portion thereof is highly rigid. The side impact beam 20 has a high load in the direction of arrow A in FIGS.
The outer panel 1 of the front door 12 when acting on the
4 and the amount of deformation of the inner panel 16 are limited.

As shown in detail in FIGS. 4 and 5, in the vicinity of the mounting and fixing portion of the side impact beam 20 at the vehicle front side end portion, that is, the bracket 24, the surface on the inner panel 16 side (that is, the vehicle interior side) A strain gauge 26 as a strain detecting means is attached to the surface of (1). The strain gauge 26 can detect the tensile strain of the attached side impact beam 20.

Further, an electric ignition type air bag device as an occupant protection device (not shown) is arranged on the front door 12, and the above-mentioned strain gauge 26 is electrically connected through an operating circuit (not shown). Has been done. Therefore, the strain gauge 26 is attached to the side impact beam 2
When a large tensile strain exceeding a predetermined value of 0 is detected,
The actuation circuit is closed to activate the airbag device.

Next, the operation of this embodiment will be described. When the vehicle reaches a sudden deceleration state with the strain gauge 26 attached to the side impact beam 20 as described above and a predetermined high load acts on the front door 12 in the direction of arrow A in FIGS. 3 and 5, The outer panel 14 of the front door 12 is deformed and the side impact beam 20 is distorted. When the side impact beam 20 is distorted, the strain gauge 26 detects the strain without delay. As a result, the operating circuit of the airbag device is closed, the airbag device is activated, and the bag body (not shown) of the airbag device bulges from the front door 12.

In this case, the side impact beam 20 is fixed to the shelf portion 22 provided on the inner panel 16 of the front door 12 via the bracket 24, and the high impact acting on any portion of the front door 12 (outer panel 14). Strain also occurs under load. Therefore, the strain gauge 26 provided on the side impact beam 20 can instantly detect a high load acting on any part of the front door 12. In other words, with only the single strain gauge 26, the front door 1
The high load acting on any part of 2 can be instantly detected. Therefore, unlike the conventional detection device, the number of parts for detecting the vehicle sudden deceleration state does not increase, the assembling property does not deteriorate, and the arrangement space is not limited.

Further, the side impact beam 20 itself has high rigidity, has little distortion when a low load is applied, and has a large strain when a high load is applied, and since the side impact beam 20 is provided with the strain gauge 26. , It is possible to determine whether a low load that does not need to operate the airbag device originally acts on the front door 12 or a high load that originally needs to operate the airbag device acts on the front door 12. It's easy.

Further, in the present embodiment, the strain gauge 26 is provided in the vicinity of the portion where the side impact beam 20 is fixed to the inner panel 16, that is, the strain gauge 26 is provided in a particularly highly rigid portion. Therefore, the strain gauge 26 is maintained in a state where it can exhibit its original function without being destroyed until the airbag device is substantially operated after the strain gauge 26 detects the vehicle rapid deceleration state. Particularly, in the present embodiment, the strain gauge 26 is attached to the surface of the side impact beam 20 on the inner panel 16 side (that is, the surface on the inner side of the vehicle interior), so that a high load acts on the front door 12. Even if the strain gauge 26 is deformed, the strain gauge 26 itself is reliably protected and is not destroyed. Therefore, the strain gauge 26
It is not necessary to make the structure of (1) robust, and therefore, it is possible to easily reduce the size and weight.

As described above, in this embodiment, the front door 12 (inner panel 16) of the side impact beam 20 is provided.
Since the strain gauge 26 capable of detecting the strain of the side impact beam 20 is provided in the vicinity of the fixed portion with respect to, the rapid deceleration state of the vehicle can be maintained without being affected by unnecessary repeated load or low acceleration (low load). The detection can be reliably performed in an extremely short time, and the size and weight can be reduced.

In the present embodiment, the strain gauge 26 as the strain detecting means is installed in the side impact beam 2.
However, the present invention is not limited to this, and is not limited to this, for example, the surface of the side impact beam 20 on the outer panel 14 side (outside the vehicle interior). It may be configured to be provided on the surface). In this case, when the outer panel 14 of the front door 12 is deformed and the side impact beam 20 is distorted, the strain gauge 26 detects this as a compressive strain without delay, whereby the airbag device can be operated.

Further, in the present embodiment, the strain gauge 26 as the strain detecting means is provided with the side impact beam 2.
0 is provided only at the vehicle front side end (near the fixed portion to the inner panel 16), but the configuration is not limited to this, and the side impact beam 20 may be provided at the vehicle rear side end or side impact beam 20. The beam 20 may be provided at both front and rear ends of the vehicle, or may be provided at an intermediate portion in the axial direction of the side impact beam 20.

Even in these cases, the rapid deceleration state of the vehicle can be reliably detected in an extremely short time without being affected by unnecessary repeated load or low acceleration (low load), and the strain gauge 26 Is maintained in a state where it can perform its original function without being destroyed.

Further, in this embodiment, the strain gauge 26 is used as the strain detecting means, but other means may be used as long as it can detect the strain of the side impact beam 20, for example, a semiconductor type strain gauge. You may use.

In the above embodiment, the vehicle sudden deceleration state detecting device 10 (strain gauge 26) is applied to the front door 12 of the vehicle. However, the invention is not limited to this, and the side impact beam 20 may be provided. Of course, it can be applied to other parts (for example, the rear door of the vehicle).

Further, in the above-described embodiment, the airbag device provided on the front door 12 is used as the occupant protection device and the configuration for operating the airbag device has been described. However, the invention is not limited to this, and other airbag devices are used. (For driver's seat, passenger's seat, etc.) and a webbing retractor, which is provided in a so-called preload device for rapidly rotating the take-up shaft in the take-up direction using a wire or the like in the event of collision Good.

[0030]

As described above, the vehicle rapid deceleration state detection device according to the present invention ensures the rapid deceleration state of the vehicle in an extremely short time without being affected by unnecessary repeated load or low acceleration (low load). It has an excellent effect that it can be detected at any time and can be made compact and lightweight at the same time.

[Brief description of drawings]

FIG. 1 is a perspective view of a front door of a vehicle to which a vehicle rapid deceleration state detection device according to an exemplary embodiment of the present invention is applied.

FIG. 2 is a schematic sectional view of a front door to which the vehicle rapid deceleration state detection device shown in FIG. 1 is applied.

3 is a cross-sectional view of the front door taken along line 3-3 of FIG.

FIG. 4 is an enlarged view of a main part of the front door shown in FIG.

5 is an enlarged cross-sectional view of a main part of the front door taken along the line 5-5 of FIG.

[Explanation of symbols]

 10 Vehicle Rapid Deceleration State Detection Device 12 Front Door 14 Outer Panel (Door Panel) 16 Inner Panel (Door Panel) 20 Side Impact Beam 26 Strain Gauge

Claims (1)

[Claims] 1. A vehicle rapid deceleration state for applying to a vehicle door in which a side impact beam is arranged inside a door panel and for detecting a rapid deceleration state of the vehicle to operate an occupant protection device provided in the vehicle. A detection device, wherein the side impact beam is provided with a strain detection means capable of detecting the strain of the side impact beam.