JP4831584B2 - Body front structure - Google Patents

Description

  The present invention relates to a vehicle body front part structure, and more particularly to a vehicle body front part structure in which a collision sensor is disposed in a vehicle body front part.

  In a vehicle such as an automobile, a collision sensor (acceleration sensor) is disposed at the front of the vehicle body in order to detect a frontal collision by the deceleration of the vehicle and deploy an occupant protection airbag provided in the passenger compartment. Yes.

  As for the mounting arrangement of this collision sensor, a bumper reinforcement extending in the vehicle width direction is arranged at a position ahead of the vehicle body from a radiator shroud arranged so as to surround the radiator arranged at the front of the vehicle body, and the upper member (bulk) of the radiator shroud A high-rigidity member is attached to the vehicle width direction center of the head upper frame), and the high-rigidity member and bumper reinforcement are connected by a connecting member, and a collision sensor is attached to the connecting member as a mounting flange for the high-rigidity member. (For example, Patent Document 1).

According to this collision sensor mounting arrangement, there is an advantage that a single collision sensor can detect not only low and high front collisions but also offset collisions in which only one of the left and right sides collides. .
Japanese Patent No. 4045760

  However, in the above-described prior art, since the collision sensor exists in the space opened to the front part of the bulkhead upper frame, there is a possibility that a hand or an object may accidentally hit the collision sensor from the outside during maintenance inspection. If a hand or an object hits the collision sensor, the collision sensor may erroneously detect the collision, and the airbag may be unnecessarily deployed. For this reason, conventionally, a separate cover for protecting the collision sensor has been provided.

  In vehicles with a short distance in the longitudinal direction of the vehicle body from the front bumper to the bulkhead upper frame, the collision sensor detects the collision during low-speed collisions (light collisions) where the airbag does not need to be deployed, and the airbag is unnecessary. There is a risk of developing.

  The problem to be solved by the present invention is that a single collision sensor not only detects a frontal collision but also detects an offset collision in which only one of the left and right sides collides, and then hits the collision sensor with a hand or an object. This avoids the collision sensor from erroneously detecting a collision.

  The vehicle body front structure according to the present invention includes a bulkhead upper frame that extends in the vehicle width direction at the vehicle body front portion and includes a substantially rectangular closed cross-sectional shape portion and a lower flange portion that extends downward from the closed cross-sectional shape portion. In addition, a sensor mounting bracket that is suspended from the closed cross-sectional shape portion and is located behind the lower flange is fixedly mounted on the closed cross-sectional shape portion, and is disposed at the vehicle rear position of the lower flange. A collision sensor is attached to the sensor mounting bracket.

  According to this vehicle body front structure, the collision sensor is located at the vehicle rearward position of the lower flange, and the collision sensor is hidden by the lower flange when viewed from the front of the vehicle body, and the lower flange serves as a barrier to the outside (vehicle body front). Hands and objects do not hit the collision sensor. This eliminates the need to provide a protective cover for the collision sensor.

  In the vehicle body front structure according to the present invention, preferably, the bulkhead upper frame is a front side frame that extends in the vehicle longitudinal direction by side stays that hang downward from both ends of the bulkhead upper frame in the vehicle width direction. A predetermined amount is coupled (connected) to the rear portion of the vehicle body from the front end portion of the vehicle body.

  According to this vehicle body front structure, even in a vehicle with a short distance in the vehicle longitudinal direction from the front bumper to the bulkhead upper frame, at the time of low-speed collision (light collision), only the front end of the front side frame is crushed, and the collision energy is detected by the collision sensor. The collision sensor does not detect a collision. As a result, the airbag does not unnecessarily deploy during a low-speed collision (light collision).

  According to the vehicle body front structure according to the present invention, preferably, the collision sensor is arranged at a central portion in the vehicle width direction.

  According to this vehicle body front structure, it is possible to satisfy a desired sensing performance for detecting a frontal collision and a left and right offset collision without using a center stay or the like by using a single collision sensor.

  In the vehicle body front portion structure according to the present invention, preferably, an energy absorbing member is further installed on a front wall portion of the bulkhead upper frame.

  According to this vehicle body front structure, the front impact load is received by the energy absorbing member, and the energy absorbing member absorbs the collision energy, so that the deceleration (G) input to the collision sensor can be controlled.

  According to the vehicle body front structure according to the present invention, the collision sensor is located at the vehicle body rear position of the lower flange, and when viewed from the front of the vehicle body, the collision sensor is hidden by the lower flange, and the lower flange serves as a barrier. Hands or objects do not hit the collision sensor from the front. Thus, it is ensured that one collision sensor detects not only a frontal collision but also an offset collision in which only one of the left and right sides collides, and the collision sensor does not detect a collision by mistake.

  Hereinafter, an embodiment of a vehicle body front structure according to the present invention will be described with reference to FIGS.

  As the vehicle body front structure, a bulkhead upper frame 10 extending substantially horizontally in the vehicle width direction is provided at the vehicle body front. As shown in FIG. 4, the bulkhead upper frame 10 is obtained by spot-welding an upper member 10 </ b> A and a lower member 10 </ b> B made of pressed steel at each of the lower flange 11 and the rear flange 12. , Having a substantially rectangular closed section 13. The lower flange portion 11 extends downward (hangs down) from the front portion of the closed cross-sectional shape portion 13 to form a curtain shape.

  As shown in FIG. 5, the upper ends of the left and right side stays 14 are joined to both ends of the closed cross-sectional shape portion 13 of the bulkhead upper frame 10 in the vehicle width direction by welding. Each of the left and right side stays 14 is made of a steel plate press-molded into a groove shape. The left and right side stays 14 hang downward from both ends in the vehicle width direction of the closed cross-sectional shape portion 13 in a substantially vertical arrangement. It is connected by welding to a bulkhead lower frame 15 made of pipe steel extending substantially horizontally in the width direction.

  The end of the bulkhead lower frame 15 in the vehicle width direction is made of a pressed steel plate that extends outward in the vehicle width direction from the connecting portion with the side stay 14 and is connected to the left and right front pillars 17 (see FIG. 1) on the upper side. The left and right front lower members 16 are joined to the tip portions by welding.

  The left and right side stays 14 are joined by welding to left and right front side frames 18 made of a pressed steel plate that extends in the longitudinal direction of the vehicle body at an intermediate portion in the vertical direction. The connecting position of the side stay 14 and the front side frame 18 is at a position a predetermined amount behind the front end portion 18A of the front side frame 18 on the front side of the vehicle body, and the front end portion 18A of the front side frame 18 is located in front of the side stay 14. It is located in front of the vehicle body from the wall 14A.

  Each of the left and right side stays 14 is connected to the middle portion of the front lower member 16 by welding at the upper end vicinity portion by a connecting member 20.

  End portions in the vehicle width direction of a front bumper beam 19 made of a pressed steel plate are joined to the front end portions 18A of the left and right front side frames 18 by welding so as to connect the left and right front side frames 18 to each other. The front bumper beam 19 extends substantially horizontally in the vehicle width direction, and an elastomer front bumper face 21 (see FIG. 1) is attached to the front portion.

  As shown in FIGS. 1 to 3, a lever mounting bracket 24 to which a hood lock release lever 23 is rotatably attached is provided by a screw 22 at a substantially central portion in the vehicle width direction of the bulkhead upper frame 10. It is fixedly attached.

  As shown in FIGS. 2 to 4, the bottom bottom wall (the bottom bottom outer wall of the lower member 10 </ b> B) of the central portion in the vehicle width direction of the closed cross-sectional shape portion 13 of the bulkhead upper frame 10 is made of a pressed steel plate. The upper piece 30A of the upside down L-shaped sensor mounting bracket 30 is fixedly mounted by welding. The sensor mounting bracket 30 has a drooping piece 30B that is bent from the upper piece 30A and hangs downward from the closed cross-sectional shape portion 13, and the whole is located behind the lower flange 11 in the vehicle body. The hanging piece 30 </ b> B of the sensor mounting bracket 30 is located behind the lower flange 11 and extends substantially horizontally with the lower flange 11, and the lower end 30 </ b> C is below the lower end 11 </ b> A of the lower flange 11.

  A collision sensor 40 is attached to the front surface of the hanging piece 30B in the vehicle body direction. Details of the mounting structure of the collision sensor 40 will be described below.

  The collision sensor 40 includes a main body casing portion 42 having a sensor main body (not shown) and having an electrical connector 41, and a mounting seat portion 44 that is continuous with the lower portion of the main body casing portion 42 and is formed through the mounting screw through hole 43. Have. The connection cable side connector 25 is detachably connected to the electrical connector 41 from the vehicle body width direction.

  A screw-through hole 31 is formed in the vicinity of the lower end of the hanging piece 30B of the mounting bracket 30 for the sensor, specifically, a portion located below the lower end portion 11A of the lower flange 11, and a nut 32 is formed on the back surface thereof. Welded.

  The collision sensor 40 is passed through the mounting screw through hole 43 of the mounting seat portion 44 and the screw through hole 31 of the sensor mounting bracket 30 of the hanging piece 30B, and is attached to the sensor mounting bracket 33 by screwing with the nut 32. 30 is fixed with screws. Since the screw-through hole 31 is below the lower end portion 11A of the lower flange 11, the operation of passing the attachment screw 33 through the attachment screw-through holes 43, 31 and screwing the nut 32 is performed in front of the bulkhead upper frame 10. It can be done without any obstacles.

  The collision sensor 40 is located at the vehicle body rear position of the lower flange 11, and the collision sensor 40, particularly the main body casing portion 42 is hidden by the lower flange 11 when viewed from the front of the vehicle body to the rear. As a result, the lower flange 11 acts as a barrier, and hands and objects do not hit the body casing portion 42 of the collision sensor 40 from the outside (front of the vehicle body). Thereby, it is not necessary to separately provide a protective cover for the collision sensor 40.

  As described above, the collision sensor 40 is disposed substantially at the center of the bulkhead upper frame 10 in the vehicle width direction (a portion adjacent to the mounting portion of the lever mounting bracket 24 with respect to the bulkhead upper frame 10). It is ensured by the two collision sensors 40 that not only the frontal collision but also the offset collision in which only one of the left and right sides collides is detected, and a hand or object hits the body casing portion 42 of the collision sensor 40 in particular. This prevents the collision sensor 40 from erroneously detecting a collision.

  The G transmission of the left and right offset collision is performed from the left and right side stays 14 to the bulkhead upper frame 10, and the collision sensor 40 is disposed at the central portion in the vehicle width direction of the bulkhead upper frame 10. The desired sensing performance for detecting a frontal collision and a left and right offset collision can be satisfied without using a center stay or the like.

  Further, a connecting point where the bulkhead upper frame 10 to which the collision sensor 40 is attached is connected to the front side frame 18 by the side stay 14 is a part of the front side frame 18 that is a predetermined amount behind the front end 18A of the vehicle front side. Therefore, even in a vehicle with a short distance in the longitudinal direction from the front bumper beam 19 to the bulkhead upper frame 10, in the case of a low-speed collision (light collision), only the front end of the front side frame 18 is crushed and the collision energy collides as it is. It is not transmitted to the sensor 40. As a result, the collision sensor 40 does not detect a collision during a low-speed collision (light collision), and the airbag does not unnecessarily deploy during a low-speed collision (light collision).

  Further, in this embodiment, the clearance (stroke area) behind the vehicle of the collision sensor 40 is the front and rear of the vehicle body between the hanging piece 30B of the sensor mounting bracket 30 and the engine room piping 25, as shown in FIG. The stroke S can be set to an appropriate value so that the deceleration of the airbag expansion is not hindered from acting properly on the collision sensor 40 by the selection of the arrangement of the piping 25 in the engine room. .

  If the collision sensor 40 interferes with the rear-positioned rigid body at the time of a collision, the collision G acting on the collision sensor 40 is reduced. However, by setting the above-described stroke S to an appropriate value, the collision G can be appropriately raised, The normal deployment of the airbag can be guaranteed.

  As another embodiment, as shown in FIG. 6, a box-shaped resin or sheet metal energy absorbing member 50 may be installed on the front wall portion of the bulkhead upper frame 10 and the side stay 14. .

  According to this embodiment, the front impact load is received by the energy absorbing member 50, and the energy absorbing member 50 absorbs a part of the collision energy, so that the deceleration (G) input to the collision sensor 40 can be controlled. The degree of collision detected by the collision sensor 40 can be set to the required value without depending on the sensitivity of the collision sensor 40.

1 is a front view showing one embodiment of a vehicle body front structure according to the present invention. It is an enlarged front view of the principal part of the vehicle body front part structure by this embodiment. It is the enlarged front view which looked up the principal part of the vehicle body front part structure by this embodiment from the downward direction. FIG. 3 is an enlarged sectional view taken along line AA in FIG. 2. It is a perspective view of the vehicle body front part structure by this embodiment. It is a perspective view of the vehicle body front part structure by other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Bulkhead upper frame 11 Lower flange 12 Rear flange 13 Closed cross-section shape part 14 Side stay 15 Bulkhead lower frame 16 Front lower member 17 Front pillar 18 Front side frame 19 Front bumper beam 20 Connecting member 21 Front bumper face 23 Hood release Lever 24 Lever mounting bracket 30 Sensor mounting bracket 31 Mounting screw through hole 40 Collision sensor 41 Electrical connector 42 Body casing portion 43 Mounting screw through hole 44 Mounting seat portion 50 Energy absorbing member

Claims (5)

A vehicle body front structure to which a collision sensor can be attached,
A bulkhead upper frame configured by a substantially rectangular closed cross-section portion and a lower flange portion extending downward from the closed cross-section shape portion, extending in the vehicle width direction at the vehicle body front portion ;
A sensor mounting bracket having an upper piece fixedly attached to the closed cross-sectional shape portion, a bent piece bent from the upper piece and suspended from the closed cross-sectional shape portion and positioned at the rear of the vehicle body from the lower flange. Including
The collision sensor has a main body casing portion having a built-in sensor main body and an electric connector, and a mounting seat portion formed continuously through a lower portion of the main body casing portion and through an attachment screw hole.
In the portion where the hanging piece of the bracket for mounting the sensor is located below the lower end portion of the lower flange, a screw-through hole is formed through, and a nut is welded to the back surface thereof ,
The collision sensor is disposed at a vehicle rearward position of the lower flange by an attachment screw that is passed through the attachment screw through hole of the attachment seat portion and the screw through hole of the drooping piece and is screw-engaged with the nut. A vehicle body front structure fixed to the sensor mounting bracket by screws .   The bulkhead upper frame is a predetermined amount behind the front end portion of the front side frame of the front side frame extending in the longitudinal direction of the vehicle body by a side stay hanging downward from both ends of the bulkhead upper frame in the vehicle width direction. The vehicle body front part structure according to claim 1, wherein the vehicle body front part structure is coupled to a part. The vehicle body front part structure according to claim 1, wherein the collision sensor is disposed at a central portion in a vehicle width direction.
A lever mounting bracket for rotatably mounting a hood lock release lever is fixedly attached to a central portion in the vehicle width direction of the bulkhead upper frame,
3. The vehicle body according to claim 1, wherein the collision sensor is arranged at a central portion in the vehicle width direction adjacent to and continuously adjacent to a mounting portion of the lever mounting bracket with respect to the bulkhead upper frame of the lower flange. Front structure. The vehicle body front part structure according to any one of claims 1 to 4 , wherein an energy absorbing member is installed on a front wall part of the bulkhead upper frame.

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