JPH0752739A - Mounting structure of car crash detecting sensor - Google Patents

Abstract

PURPOSE:To reduce the number of impact detection sensors to the utmost as detecting a degree of acceleration in the longitudinal direction of a car body in time of a car crash in an accurate manner by securing the impact detection sensor to a tunnel part extending in the body longitudinal direction at an almost central part in the car width direction, in a body floor. CONSTITUTION:In a tunnel part 6 installed in a body floor, a G sensor 12 as an impact detection sensor is secured to the front end via a mounting bracket 11 which is provided with a sensor locking part 13 and a leg part 14, and this sensor locking part 13 consists of a mount part 15 and a regulating wall part 16. In addition, a secured part 26 is installed in the G sensor 12 and locked to the sensor locking part 13 with a clamping bolt 17. In consequence, making a full use of high rigidity in the body longitudinal direction of the tunnel part 6, acceleration in the longitudinal direction in time of a car crash is accurately detected, and further since it is situated in a central part in the car width direction, one G sensor alone is able to cope with every type of collisions.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle collision detection sensor mounting structure.

[0002]

2. Description of the Related Art A recent vehicle is a safety device for protecting an occupant at the time of a collision, and an air bag deployed in the passenger compartment at the time of a collision or a pre-tension type which is forcibly pulled (tensioned) at the time of a collision. Such a safety device is equipped with a seat belt, etc., and it should be operated reliably in a collision where occupants are expected to be damaged, but should not be operated in a light collision where the bumper is slightly deformed. Is required. Therefore, as shown in Japanese Patent Laid-Open No. 3-148348, a collision detection sensor (G sensor) mounted on the vehicle body.
It is proposed to detect the collision deceleration (acceleration) by the above, perform a predetermined calculation based on the output signal from the collision detection sensor, and determine whether to activate the safety device based on the calculation result. Has been done.

By the way, the collision detection sensor as described above
Are generally attached to the side frame. This is because the rigidity of the side frame is high in the front-rear direction of the vehicle body, and if a collision detection sensor is provided in front of the side frame, it is attached to the side frame when a collision load acts on the side frame. This is because the collision sensor can accurately detect the acceleration in the front-rear direction of the vehicle body at an earlier timing after the collision occurs.

[0004]

[Problems to be Solved by the Invention]
If a collision sensor is attached to the frame, it is necessary to consider both the collisions on the left and right sides, and the collision detection sensors must be attached to the left and right side frames, respectively. The present invention has been made in view of the above circumstances, and an object of the vehicle is to reduce the number of collision detection sensors as much as possible while assuming that the acceleration in the vehicle front-rear direction at the time of a collision can be accurately detected. It is to provide a mounting structure for a collision detection sensor.

[0005]

In order to achieve the above object, according to the present invention (the first invention), there is provided a tunnel portion in the vehicle body floor, which is substantially central in the vehicle width direction and extends in the vehicle longitudinal direction. The collision detection sensor is fixed to the vehicle collision detection sensor. With the above-described configuration, the tunnel portion extends in the front-rear direction of the vehicle body while being curved upward in a protruding shape, and has high rigidity in the front-rear direction of the vehicle body. Therefore, the collision detection sensor is fixed to the tunnel portion. As a result, the high rigidity of the tunnel portion can be utilized for acceleration detection during a collision, and the acceleration in the vehicle front-rear direction during a collision can be accurately detected. On the other hand, since the tunnel portion is located at the center in the vehicle width direction, even if either one of the left and right side collisions occurs, the same impact load can be detected for the same degree of collision, and one collision detection sensor can be used. It will be possible to deal with all kinds of collisions. Therefore, it is assumed that the acceleration in the longitudinal direction of the vehicle body can be accurately detected, and the collision sensor-
The number of can be reduced as much as possible.

Further, in order to achieve the above-mentioned object, according to the present invention (second invention), in the first aspect, the collision detection sensor continuously changes the collision change state into an electric signal. It has a configuration that is the type to be detected. With the above-described configuration, in addition to producing the same effect as that of the first aspect of the invention, the collision detection sensor is of a type that continuously detects the collision change state by converting it into an electric signal. Is deformed at the time of a collision, no matter how the posture of the collision detection sensor changes, the collision state is continuously detected, and the posture changes like a so-called G-ball type collision detection sensor. By doing so, the detection of the collision state is not affected. Therefore, the acceleration in the longitudinal direction of the vehicle body at the time of a collision can be detected more accurately.

Further, in order to achieve the above-mentioned object, according to the present invention (third invention), the collision detection sensor is located at a front end portion of the tunnel portion. , As a configuration. With the above configuration,
Besides producing the same effect as the above-mentioned first or second invention,
Since the collision detection sensor is located at the front end of the tunnel portion, the collision can be detected at an earlier timing. Therefore, the collision state can be determined more accurately.

Furthermore, in order to achieve the above-mentioned object, according to the present invention (fourth invention), in any one of claims 1 to 3, between the collision detection sensor and the tunnel portion. A mounting bracket for fixing the collision detection sensor to the tunnel portion is interposed, and the mounting bracket is fixed to the sensor fixing portion for mounting the collision detection sensor, and the sensor fixing portion is fixed to the tunnel portion. A leg portion that is lifted from the tunnel portion, and a connecting member that connects the dash panel and the mounting bracket is provided between the mounting bracket and the dash panel. . With the above-described configuration, in addition to the same operation as that of the first, second, and third inventions described above, a sensor-fixing portion and a tunnel portion of the mounting bracket based on the mounting bracket having legs are provided. To form a space between the
It can be used as a passage space for loess. On the other hand, in the case of a light collision, etc., regarding that the mounting bracket easily vibrates in the vehicle front-rear direction based on the legs,
The connection member suppresses the connection by connecting the mounting bracket and the dash panel, and at the time of a light collision, the collision detection sensor detects an appropriate acceleration according to the collision state. Therefore, it is possible to maintain an accurate determination of the collision state while improving the workability of arranging the harnesses.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 1 denotes a vehicle, and the inside of the vehicle 1 is partitioned by a dash panel (dash lower panel) 2 into an engine room 3 and a vehicle interior 4. In the vehicle compartment 4,
A vehicle body floor 5 is provided below the vehicle body floor 5, and a tunnel portion 6 is provided on the vehicle body floor 5. The tunnel portion 6 extends toward the rear of the vehicle body from the dash panel 2 in a state where it is curved upward in the vehicle width direction at the center in the vehicle width direction. It is configured to include a portion 6a and a side surface portion 6b that hangs downward from both sides in the width direction of the upper surface portion 6a. On the other hand, above the interior of the vehicle compartment 4, the dash panel 2
An instrument panel 7 is provided adjacent to, and a steering wheel 8 is provided on the vehicle body rear side of the instrument panel 7. In the present embodiment, an air bag device 9 is provided in the steering wheel 8 as a safety device, and the air bag device 9 operates in accordance with a gas pressure based on a control signal from a control unit (not shown). An inflator (not shown) for generating the air is activated, and the airbag 10 is driven by the gas pressure of the inflator.
Is to be inflated and deployed.

As shown in FIGS. 1 and 2, the tunnel portion 6 has a G sensor (acceleration sensor) 12 as a collision detection sensor at a front end portion of the tunnel portion 6 via a mounting bracket 11. Is fixed.

The mounting bracket 11 is made of steel, for example, and is provided with a sensor fixing portion 13 and a leg portion 14 as shown in FIGS. The sensor-fixing part 13 has a flat mounting table part 15 and a restricting wall part 16 standing upright in front of the mounting table part 15. The mounting table part 15 and the restricting wall part 16 are Fixing bolts 17 are erected in each. The leg portion 14 has a rear leg portion 18 and a front leg portion 19. The rear leg portion 18 is provided with left and right branch leg portions 20a and 20b, which extend downward from the rear portion of the mounting table portion 15 and then branch left and right, respectively. 2. As shown in FIG. 5, it is fixed to the left and right side surface portions 6b of the tunnel portion 6 with bolts 21. The front leg portion 19 includes left and right leg portions 22a and 22b.
It has each. The left and right leg portions 22a, 22b
2 to 5, as shown in FIG. 2 to FIG. 5, each of the left and right leg portions a and 22b has a tip end portion that extends from each side portion of the mounting base portion 15 in the vehicle width direction and descends downward and extends toward the front of the vehicle body. In the present embodiment, in order to enhance the supporting force in the front-rear direction of the vehicle body, the stud bolts 23 and the nuts 24 that are erected on the dash panel 2 are used to fix the dash panel 2 instead of the tunnel portion 6. ing. The front and rear leg portions 19 and 18 are set so that the flat mounting table portion 15 of the sensor-fixing portion 13 is horizontal and the sensor-fixing portion 13 is lifted from the tunnel portion 6 with the above-described configuration. As a result, a passable space 25 is formed between the sensor-fixing portion 13 and the tunnel portion 6, as shown in FIGS. 2, 4, and 5.

The G sensor 12 is for detecting acceleration in the longitudinal direction of the vehicle body, and is not a type utilizing a so-called G ball, but a type for continuously detecting the change state of collision into an electric signal. The output signal of the G sensor-12 is to be output to a control unit (not shown) that performs a predetermined calculation. More specifically, as the G sensor-12, for example, Japanese Patent Laid-Open No. 3-14
As shown in Japanese Patent No. 8347, a device including a deceleration transducer circuit that outputs an output signal that continuously represents the deceleration that occurs when a vehicle collides is used. The G sensor-12 is housed in a box as shown in FIG. The G sensor-12 has a fixed portion 26 corresponding to the fixing bolt 17 of the sensor fixing portion 13.
This fixed portion 26 is fixed to the sensor-fixing portion 13 by using the fixing bolt 17 and the nut 27, whereby the G sensor-12 is attached to the mounting bracket 11 (sensor-fixing portion 13). ) Is fixed.

A connecting portion 28 as a connecting member is provided between the dash panel 2 and the mounting bracket 11 as shown in FIGS. This connecting portion 28
In the present embodiment, are provided on the respective side portions of the restriction wall portion 16 of the sensor-fixing portion 13, and they are slightly upward in the range of the left and right leg portions 22a and 22b of the front leg portion 19. While going up, it extends to the front of the car body,
The tip of each connecting portion 28 is fixed to the dash panel 2 by using a stud bolt 29 and a nut 30 that are planted in the dash panel 2. As a result, the dash panel 2 and the mounting bracket 11 are connected to each other via the connecting portion 28 above the sensor-fixing portion 13 of the mounting bracket 11.

Therefore, in the above mounting structure,
Since the G sensor-12 is fixed to the tunnel portion 6, it is possible to utilize the characteristic of the tunnel portion 6, that is, the characteristic of extending in the vehicle front-rear direction in a state of being curved upward in a protruding shape and exhibiting high rigidity in the vehicle front-rear direction. Therefore, the acceleration in the vehicle front-rear direction at the time of a collision can be accurately detected. In addition, since the tunnel portion 6 is located at the center in the vehicle width direction, by fixing the G sensor-12 to it, even if either one of the left and right side collisions occurs, the same impact load can be detected for the same degree of collision. Becomes one G
The sensor 12 can deal with all kinds of collisions. As a result, the number of G sensors-12 can be reduced to one while assuming that the acceleration in the vehicle front-rear direction can be accurately detected.

Further, since the G sensor-12 is of a type that continuously detects and changes the collision change state into an electric signal, the tunnel portion 6 is deformed at the time of collision and the posture of the G sensor-12 changes. Even so, the collision state is continuously detected, and a so-called G-ball type collision detection sensor-
As described above, the change in the posture does not affect the detection of the collision state, that is, the detection accuracy does not decrease. Therefore, the acceleration in the vehicle front-rear direction at the time of a collision can be detected more accurately. When a G-ball type collision detection sensor is used, the ball
The ru itself is a contact that energizes the detonator. In this type, even if the ball moves due to the impact that should cause the airbag to detonate and the contact is closed once, the above deformation occurs and the position of the G ball changes, and the contact opens. Therefore, the detonator cannot be sufficiently energized, and the detonation may be incomplete. On the other hand, when the G sensor as in this embodiment is used, the signal from the G sensor is input and the control circuit (ignition circuit 36 in Japanese Patent Laid-Open No. 3-148348) energizes the detonator. Even if the attitude of the G sensor changes after the collision is determined to cause the airbag to detonate, the problem caused by using the G ball type does not occur.

Further, since the G sensor-12 is located at the front end portion of the tunnel portion 6, the G sensor-12 detects a collision at an earlier timing, and accordingly, the collision state is further detected. You will be able to make accurate decisions.

Furthermore, the G sensor 12 is fixed to the tunnel portion 6 via the mounting bracket 11 having the front and rear leg portions 19 and 18, and the sensor of the mounting bracket 11 is fixed.
Since the passable space 25 is formed between the fixed portion 13 and the tunnel portion 6, the passable space 25
2 can be used as a passage space for the harnesses 31, as shown in FIG. 2, and the workability of disposing the harnesses 31 can be improved. On the other hand, in a light collision or the like, the mounting bracket 11 easily vibrates (resonates) in the vehicle front-rear direction based on the rear leg portion 18, but the connecting portions 28, 22a, 22b connect the mounting bracket 11 and the dash panel 2 to each other. Since the sensor of the mounting bracket 11 is connected to the front side of the fixing portion 13, the above vibration is suppressed, and the G sensor-
12 will detect the appropriate acceleration according to the said collision state. Therefore, it is possible to prevent the airbag 10 from malfunctioning at the time of a light collision or the like.

In order to support the above contents, when the mounting bracket 11 according to the present embodiment is used (hereinafter referred to as the present embodiment type), the mounting bracket 1 according to the present embodiment is used.
In the case of using a mounting bracket excluding the connecting portion 28 from 1 (hereinafter, referred to as a comparative example type), the front and rear of the vehicle body detected by the G sensor-12 during a light collision (collision at a vehicle speed of about 13 km / h) The directional acceleration was investigated. As a result, the content of FIG. 6 was obtained for the comparative example type, but the content of FIG. 7 was obtained for the type of this example, which is approximately the same as the upper surface of the tunnel portion, and the connecting portion 28 was effective in reducing vibration. Indicated.

[0019]

As described above, in the first to fourth aspects of the invention, the number of collision sensors can be reduced as much as possible on the premise that the acceleration in the vehicle longitudinal direction can be accurately detected. According to the second aspect of the present invention, the acceleration in the vehicle front-rear direction at the time of a collision can be detected more accurately. According to the third invention, the collision state can be determined more accurately. According to the fourth aspect of the present invention, it is possible to maintain an accurate determination of the collision state while improving the workability of arranging the harnesses.

[Brief description of drawings]

FIG. 1 is an explanatory diagram illustrating an inside of a vehicle according to an embodiment.

FIG. 2 is a perspective view of the vicinity of the front end portion of the tunnel portion on the front side of the vehicle body as seen from the vehicle body rear side toward the vehicle body front side.

FIG. 3 is a plan view showing a mounting bracket according to an embodiment.

FIG. 4 is a front view of FIG.

5 is a left side view of FIG.

FIG. 6 is a diagram showing detection contents detected by a G sensor during a light collision when a comparative example type is used.

FIG. 7 is a diagram showing a detection content detected by a G sensor at the time of a light collision when the type of the present embodiment is used.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 vehicle 2 dash panel 5 vehicle body floor 6 tunnel section 11 mounting bracket 12 G sensor-13 sensor-fixing section 14 leg section 18 rear leg section 28 connecting section

Claims (4)

[Claims] 1. A structure for mounting a collision detection sensor of a vehicle, wherein a collision detection sensor is fixed to a tunnel portion extending substantially in the vehicle width direction and substantially in the center in the vehicle width direction and extending in the vehicle longitudinal direction. 2. The mounting of a collision detection sensor for a vehicle according to claim 1, wherein the collision detection sensor is of a type that continuously detects a collision change state by changing it into an electric signal. Construction. 3. The collision detection sensor for a vehicle according to claim 1, wherein the collision detection sensor is located at a front end portion of the tunnel portion.
Mounting structure. 4. The mounting bracket according to claim 1, wherein a mounting bracket for fixing the collision detection sensor to the tunnel section is interposed between the collision detection sensor and the tunnel section. Has a sensor-fixing part to which the collision detection sensor is attached, and a leg part fixed to the tunnel part so as to lift the sensor-fixing part from the tunnel part. The mounting bracket and the dash panel A connecting member for connecting the dash panel and the mounting bracket is provided between the mounting structure and the mounting structure for the collision detection sensor of the vehicle.