JP2011143825A - Pedestrian collision detecting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a pedestrian collision detecting device capable of improving accuracy of detection in a constitution for detecting collision with a pedestrian by using a pressure chamber (chamber member equipped with the same). <P>SOLUTION: A collision determination system includes the chamber member 20 which is arranged so that a vehicle width direction becomes its longitudinal direction, whose inner part is a pressure chamber 22. The chamber member 20 is arranged next to a front face 14A of a bumper reinforcement 14. A bumper absorber 28 is arranged between a bumper cover and the bumper reinforcement 14. The bumper absorber 28 includes: a body 30 arranged at the bottom; and a gap stuffing part 32 arranged in a gap between the chamber member 20 and the bumper cover. Further, an irregular part 46 is formed on a surface opposing to the chamber member 20 in the gap stuffing part 32. When a leg part of the pedestrian make an intrusion, the chamber member 20 is to be pressured by two projecting parts 42. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a pedestrian collision detection device for detecting a pedestrian collision with a vehicle bumper.

  A collision detection tube filled with an incompressible fluid is inserted between a hard shock absorber and a soft shock absorber inserted in the front bumper, and a pressure sensor is installed at the center in the longitudinal direction of the collision detection tube. There is known a vehicular collision discriminating apparatus that determines a pedestrian collision based on an output signal of the pressure sensor (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 11-310095 (FIG. 14)

  However, the above-described conventional technique has a problem that the detection accuracy when detecting a collision with a pedestrian is lowered. That is, in general, the curvature differs in the vehicle width direction between the front bumper cover and the bumper reinforcement. For this reason, the distance between the front bumper cover and the front bumper reinforcement is the longest at the center in the vehicle width direction. As a result, the thickness in the vehicle front-rear direction of the bumper absorber disposed between the front bumper cover and the front bumper reinforcement is increased at the center in the vehicle width direction. For this reason, in the center part of the vehicle width direction, it becomes difficult to apply a load to the collision detection tube at the time of a pedestrian collision, and it is difficult to detect a collision with a pedestrian.

  In particular, when the outside air temperature is low, the bumper absorber becomes stiff and the rigidity increases, so when the pedestrian collides with the front bumper, the bumper absorber does not dent locally and pushes the collision detection tube, The bumper absorber presses the collision detection tube in a wide range centering on the collision site. For this reason, the pressure change of a collision detection tube becomes small, and it becomes difficult to detect having collided with the pedestrian. In order to solve this problem, it is conceivable to arrange the collision detection tube on the rear surface of the bumper cover along the bumper cover. However, in this case, the detection accuracy varies between the central portion side and both end portions in the vehicle width direction due to the shape (curvature) of the bumper cover.

  Thus, when pressing the pressure detection type collision detection means via the bumper absorber, there is a possibility that the collision detection accuracy of the pedestrian may be lowered due to various factors. Therefore, in this respect, there is room for improvement in the conventional technique.

  In consideration of the above-described facts, the present invention provides a pedestrian collision detection device capable of improving detection accuracy in a configuration for detecting a collision with a pedestrian using a pressure chamber (chamber member provided with). Is the purpose.

  The pedestrian collision detection device according to the first aspect of the present invention includes a bumper reinforcement arranged with the vehicle width direction as a longitudinal direction, and arranged outside the bumper reinforcement in the front-rear direction of the vehicle and along the bumper reinforcement. The bumper cover is arranged with the vehicle width direction as the longitudinal direction, and the central portion in the vehicle width direction in the plan view swells outward from the both ends in the vehicle longitudinal direction, and is interposed between the bumper cover and the bumper reinforcement. And a bumper absorber for energy absorption arranged with the vehicle width direction as the longitudinal direction, and is arranged adjacent to the outer side surface of the bumper reinforcement in the vehicle longitudinal direction. Along the bumper reinforcement with the vehicle width direction as the longitudinal direction. And a chamber member whose inside is a pressure chamber, a pressure detector that is disposed inside the chamber member in the front-rear direction of the vehicle and outputs a signal corresponding to a pressure change in the pressure chamber, and an output of the pressure detector A collision determination unit that determines whether or not the vehicle has collided with a pedestrian, a vehicle width direction center side of the bumper absorber, a vehicle front-rear direction outer surface of the chamber member in a plan view, and a vehicle of the bumper cover A gap portion that is provided so as to be packed in a gap with the inner side surface in the front-rear direction, and in which an uneven portion is formed along the longitudinal direction of the chamber member on a surface facing the outer side surface in the vehicle front-rear direction of the chamber member; It is equipped with.

  The pedestrian collision detection device according to a second aspect of the present invention is the pedestrian collision detection device according to the first aspect, wherein the chamber member is disposed on an upper portion of an outer surface of the bumper reinforcement in the vehicle front-rear direction, and the bumper absorber. Is configured to include the gap portion and a main body portion disposed at the lower portion of the outer side surface in the vehicle front-rear direction of the bumper reinforcement, and a part of the lower surface of the gap portion is formed in the main body portion. It is connected.

  The pedestrian collision detection device according to the third aspect of the present invention is the pedestrian collision detection device according to the first or second aspect, wherein the two adjacent convex portions are mainly used when the leg portion enters due to a collision with a pedestrian. The width of the convex part and the concave part of the concavo-convex part is set so that the chamber member is pressed.

  The pedestrian collision detection device according to the present invention as set forth in claim 4 is a bumper reinforcement arranged with the vehicle width direction as a longitudinal direction, and arranged outside the bumper reinforcement in the front-rear direction of the vehicle and along the bumper reinforcement. The bumper cover is arranged with the vehicle width direction as the longitudinal direction, and the central portion in the vehicle width direction in the plan view swells outward from the both ends in the vehicle longitudinal direction, and is interposed between the bumper cover and the bumper reinforcement. And a bumper absorber for energy absorption arranged with the vehicle width direction as a longitudinal direction, and applied to a bumper cover adjacent to the vehicle front-rear inner side surface of the bumper cover. And the central part in the vehicle width direction swells outward in the vehicle front-rear direction from both ends in plan view. A chamber member that is formed into an elliptical shape and has a pressure chamber inside, a pressure detector that is disposed inside the chamber member in the front-rear direction of the vehicle and outputs a signal corresponding to a pressure change in the pressure chamber; A collision determination unit that determines whether or not the vehicle has collided with a pedestrian based on the output of the detector, and an inner side surface of the chamber member in the vehicle front-rear direction in plan view as well as provided in the vehicle width direction center side of the bumper absorber And a gap filling portion provided so as to be filled in a gap between the bumper reinforcement and the outer side surface in the vehicle front-rear direction.

  According to the first aspect of the present invention, when a pedestrian collides with the center side of the vehicle bumper in the vehicle width direction, the bumper absorber is deformed via the bumper cover, so that the energy at the time of the collision is absorbed. At this time, the pressure in the pressure chamber is changed by pressing the chamber member by the gap filling portion (the convex portion of the uneven portion), and this pressure change is detected by the pressure detector. The collision determination unit determines whether or not the vehicle has collided with a pedestrian based on the output of the pressure detector.

  Here, in this invention, the uneven | corrugated | grooved part is formed along the longitudinal direction of a chamber member in the opposing surface with the vehicle front-back direction outer surface of the chamber member in a gap filling part. For this reason, even if the outside air temperature is low and the gap filling part is hardened and the rigidity of the gap filling part is increased, the entire gap filling part does not press the chamber member, but the convex part of the uneven part is not the chamber. Press the member. For this reason, the collision load at the time of collision is appropriately transmitted to the pressure chamber.

  According to the second aspect of the present invention, the chamber member is arranged on the upper portion of the outer side surface of the bumper reinforcement in the vehicle front-rear direction. For this reason, only the collision detection with a pedestrian is detectable compared with the case where the chamber member is arrange | positioned in the lower part of the outer side surface of the vehicle front-back direction in bumper reinforcement. That is, generally when a pedestrian collides, the pedestrian falls to the upper side of the bumper cover. On the other hand, when it collides with a pole or the like, the pole or the like falls down below the bumper cover. For this reason, only the collision with the pedestrian can be detected when the chamber member is arranged on the upper side of the outer side surface of the bumper reinforcement in the vehicle front-rear direction.

  Here, in the present invention, a part of the lower surface of the gap filling portion is connected to the main body portion of the bumper absorber. In other words, the entire bottom surface of the gap filling portion is not connected to the main body portion of the bumper absorber, but is partially connected to the main body portion of the bumper absorber. For this reason, the gap filling portion is substantially separated from the main body portion of the bumper absorber, and the leg protection performance of the main body portion is not affected.

  According to the third aspect of the present invention, when the leg portion enters due to a collision with a pedestrian, the chamber member is pressed mainly by the two convex portions. That is, when the leg portion enters, the chamber member is pressed with a volume corresponding to two protrusions with respect to the leg entry width, so that a stable output can be obtained without impairing the productivity of the bumper absorber.

  According to the fourth aspect of the present invention, since the chamber member is disposed along the bumper cover adjacent to the inner side surface of the bumper cover in the vehicle front-rear direction, the collision load with the pedestrian is directly applied to the pressure chamber. Communicated. For this reason, compared with the case where the collision load with a pedestrian is transmitted via a bumper absorber, detection accuracy becomes high.

  However, since the bumper cover has a shape in which the central portion in the vehicle width direction swells outward in the vehicle front-rear direction from both ends, when the chamber member is disposed along the bumper cover, the central portion side of the bumper cover Then, the collision load with the leg part of a pedestrian tends to increase. On the other hand, the both ends of the bumper cover have a large angle with respect to the vehicle width direction when seen in a plan view, so that the collision load with the pedestrian's legs tends to be small. On the other hand, in the present invention, since the gap filling portion is arranged on the vehicle width direction center portion side of the bumper cover, the collision load is alleviated and a just good load is transmitted to the pressure chamber. Further, on both end sides in the vehicle width direction of the bumper cover, there is no gap portion adjacent to the inner side surface of the chamber member in the vehicle front-rear direction. That is, the outer side surfaces of the bumper reinforcement in the vehicle front-rear direction are arranged to face each other. For this reason, since the chamber member is supported on the outer side surface of the bumper reinforcement in the vehicle front-rear direction, a load (reaction force) is transmitted to the pressure chamber also from the outer side surface of the bumper reinforcement in the vehicle front-rear direction. Accordingly, even when the chamber member collides with the pedestrian on both ends in the vehicle width direction, an appropriate collision load is transmitted to the pressure chamber. That is, variations in detection accuracy in the vehicle width direction are eliminated or reduced.

  The pedestrian collision detection device according to the first aspect of the present invention is configured to detect a collision with a pedestrian using a pressure chamber (chamber member provided with), and has a detection accuracy (even in a low temperature environment). It has an excellent effect that it can be improved.

  The pedestrian collision detection device according to the present invention described in claim 2 has an excellent effect that the leg protection performance of the pedestrian of the bumper absorber can be satisfactorily maintained.

  The pedestrian collision detection device according to the third aspect of the present invention has an excellent effect that a stable output can be obtained at the time of leg intrusion and the productivity of the bumper absorber is also kept good.

  According to a fourth aspect of the present invention, there is provided a pedestrian collision detection device according to the present invention, wherein a pressure chamber (chamber member provided with) is used to detect a collision with a pedestrian (the pressure chamber is disposed on the bumper cover side). In this case, the detection accuracy can be improved.

It is a principal part expansion perspective view which shows a state when the front bumper to which the pedestrian collision detection apparatus which concerns on 1st Embodiment is applied is cut | disconnected by the vertical surface containing a vehicle front-back direction. It is a longitudinal cross-sectional view of the front bumper which shows the state cut | disconnected by 2-2 line | wire of FIG. It is a perspective view which shows the bumper absorber shown by FIG. 1 alone. 1 is a plan view showing a schematic overall configuration of a collision determination system according to a first embodiment. It is explanatory drawing for demonstrating the dimension setting of each part of the uneven | corrugated | grooved part of the gap filling part shown by FIG. It is related with the comparison shown in order to demonstrate the effect of the pedestrian collision detection apparatus which concerns on 1st Embodiment, (A) is a longitudinal cross-sectional view of a front bumper, (B) is the top view. It is explanatory drawing which shows the deformation | transformation state of a bumper cover and a bumper absorber when it collides with a pedestrian in the structure shown by FIG. (A) is the perspective view corresponding to FIG. 1 which shows another comparison which provided the gap filling part in the clearance gap, (B) is a schematic plan view of the front bumper which concerns on the said comparison. It is a schematic perspective view of the front bumper to which the pedestrian collision detection device concerning a 2nd embodiment was applied. FIG. 10 is a longitudinal sectional view (cross section of the center portion) corresponding to FIG. 2 showing a sectional structure of the front bumper shown in FIG. 9. It is a longitudinal cross-sectional view (cross section of a side part) which shows the cross-section of the front bumper shown by FIG.

[First Embodiment]
Hereinafter, a first embodiment of a pedestrian collision detection apparatus according to the present invention will be described with reference to FIGS. In these figures, an arrow FR appropriately shown indicates the vehicle front side, an arrow UP indicates the vehicle upper side, and an arrow IN indicates the vehicle width direction inner side.

  FIG. 4 shows a schematic overall cross-sectional view of a schematic overall configuration of a collision determination system 10 as a pedestrian collision detection device according to the present embodiment. As shown in this figure, the collision determination system 10 is applied to a front bumper 12 as a vehicular bumper disposed at the front end of an automobile, so as to determine whether or not there is a collision with the front bumper 12. It has become. This will be specifically described below.

  The front bumper 12 includes a bumper reinforcement 14 which is a bumper skeleton member. The bumper reinforcement 14 is made of, for example, a metal material such as iron or aluminum, and is configured as a skeleton member arranged with the vehicle width direction as a longitudinal direction. The bumper reinforcement 14 is supported with respect to the vehicle body across the front ends 16A of the pair of left and right front side members 16 constituting the skeleton member on the vehicle body side.

  The front bumper 12 includes a bumper cover 18 that covers the bumper reinforcement 14 from the outside in the vehicle longitudinal direction, that is, from the front side. The bumper cover 18 is made of a resin material or the like, and has a shape in which a center portion 18A in the vehicle width direction swells forward of the vehicle width direction from both end portions 18B in the vehicle width direction in a plan view. Further, the bumper cover 18 is fixedly supported to the vehicle body at a portion not shown so that a space S is formed between the bumper cover 18 and the bumper reinforcement 14.

  A chamber member 20 is disposed in the space S between the bumper reinforcement 14 and the bumper cover 18 in the front bumper 12. The chamber member 20 is configured as a hollow structure disposed with the vehicle width direction as a longitudinal direction, and is fixedly attached to the front surface 14A and the upper surface of the bumper reinforcement 14. The chamber member 20 is substantially coincident with the positions of both ends 14B of the bumper reinforcement 14 at both ends in the longitudinal direction.

  The chamber member 20 has a rigidity capable of maintaining its shape (hollow cross-sectional shape) in a state of being fixedly attached to the bumper reinforcement 14 as described above, and is communicated with the atmosphere at a position (not shown). It has a communication hole. Therefore, normally (statically), the pressure chamber 22 that is the internal space of the chamber member 20 is configured to be at atmospheric pressure. The chamber member 20 is crushed while receiving a comparatively low compressive load from the front of the vehicle and escaping air from the communication hole, and the volume of the pressure chamber 22 is reduced while dynamically changing the internal pressure of the pressure chamber 22. ing.

  Furthermore, the collision determination system 10 includes a pair of pressure sensors 24 as pressure detectors that output a signal corresponding to the pressure in the pressure chamber 22. Each pressure sensor 24 is configured to output the same signal for the same pressure, and is configured to output a signal corresponding to the pressure in the pressure chamber 22 to an ECU 26 described later. In the following description, when the pressure sensors 24 are distinguished, for convenience, one pressure sensor 24 may be referred to as a first pressure sensor 24A and the other pressure sensor 24 may be referred to as a second pressure sensor 24B.

  These pressure sensors 24 are arranged symmetrically with respect to a center line CL that equally divides the chamber member 20 in the longitudinal direction. More specifically, the first pressure sensor 24 </ b> A is disposed at the center between the longitudinal end 20 </ b> A of the chamber member 20 and the center line CL. The second pressure sensor 24B is disposed at the center between the other end 20B in the longitudinal direction of the chamber member 20 and the center line CL. In other words, when the total length along the vehicle width direction of the chamber member 20 is L, the first pressure sensor 24A is disposed at a position where the distance from the longitudinal end 20A of the chamber member 20 is L / 4, The second pressure sensor 24B is disposed at a position where the distance from the other longitudinal end 20B of the chamber member 20 is L / 4.

  Therefore, in the collision determination system 10, at least one of the pair of pressure sensors 24 is located within a distance L / 4 from the collision position even when the collision object collides with any position in the longitudinal direction of the front bumper 12, that is, the chamber member 20. It is supposed to be configured. Further, the distance difference between the pair of pressure sensors 24 and the collision position is within L / 2 (within a range of 0 to L / 2).

  A bumper absorber 28 made of urethane foam or the like is disposed between the front surface 14A of the bumper reinforcement 14 and the bumper cover 18 with the vehicle width direction as a longitudinal direction. The bumper absorber 28 is compressed and deformed with respect to the frontal collision to absorb impact energy. Therefore, in the collision determination system 10, the chamber member 20 is configured to be compressed such that the volume of the pressure chamber 22 decreases as the bumper absorber 28 is compressed and deformed.

  The ECU 26 as a collision determination unit determines whether or not there is a collision with the front bumper 12 based on the output signal of the pressure sensor 24. In this embodiment, the ECU 26 is configured to determine whether or not there is a collision with the front bumper 12 based on pressure waveforms that are detection values of the two pressure sensors 24.

  The ECU 26 is set with a first threshold value Pt1 and a second threshold value Pt2 (> Pt1) that is larger than the first threshold value Pt1. The ECU 26 determines whether one of the first detection value P1 of the first pressure sensor 24A and the second pressure detection value P2 of the second pressure sensor 24B exceeds the first threshold value Pt1, and the first detection value P1 and the first detection value P1. When either one of the two pressure detection values P2 exceeds the second threshold value Pt2, it is determined that the collision object has collided with the front bumper 12.

  More specifically, the detected value P of the pressure sensor 24 positioned relatively apart from the collision position where the collision body collides with the chamber member 20 among the pair of pressure sensors 24 exceeds the first threshold value Pt1, and the relative When the detected value P of the pressure sensor 24 positioned close to the collision position exceeds the second threshold value Pt2, it is determined that the collision object has collided with the front bumper 12.

  Here, the bumper absorber 28 interposed between the front surface 14A of the bumper reinforcement 14 and the bumper cover 18 will be described in detail. As shown in FIGS. 1 to 3, the main body portion 30 is disposed on the lower side of the bumper reinforcement 14, and the gap portion 32 is disposed on the upper side of the bumper reinforcement 14. The main body 30 is provided across the entire width of the space S extending from the front surface 14 </ b> A of the bumper reinforcement 14 to the bumper cover 18. Further, a groove 34 that cuts from the rear end surface of the main body 30 toward the front side of the vehicle is formed in the intermediate portion in the height direction of the rear portion of the main body 30. The groove 34 is formed over the entire length of the bumper absorber 28.

  On the other hand, the gap filling portion 32 is formed only on the center side in the vehicle width direction of the bumper absorber 28. More specifically, as described above, the bumper cover 18 has a design in which the central portion 18A swells toward the front side of the vehicle with respect to the both end portions 18B. Therefore, the chamber has a generally straight shape along the vehicle width direction. A gap 36 is formed between the front surface 20 </ b> C of the member 20. The gap 36 is formed only on the center side of the bumper absorber 28 in the vehicle width direction, and is not formed on both ends of the bumper absorber 28 in the vehicle width direction. The gap filling portion 32 is formed so as to close the gap 36 formed only on the center side in the vehicle width direction of the bumper absorber 28. Further, the gap filling portion 32 is connected to the main body portion 30 via the connection portion 38 only at the front end edge of the lower surface thereof. In other words, a slit 40 that cuts from the vehicle rear side to the vehicle front side is formed at the boundary between the main body 30 and the gap filling portion 32 in the bumper absorber 28. By forming the slit 40, the gap filling portion 32 is supported by only a part (the front end edge side of the lower surface) of the main body portion 30.

  As can be seen from the above, in the layout of the present embodiment, the chamber member 20 is disposed in the rear portion of the space S adjacent to the front surface 14A of the bumper reinforcement 14 and adjacent to the front surface 20A of the chamber member 20. A gap filling portion 32 is disposed on the front center side of the space S. On the rear surface of the gap filling portion 32, that is, the surface facing the chamber member 20, uneven portions 46 in which convex portions 42 and concave portions 44 are alternately arranged along the longitudinal direction of the chamber member 20 are formed. Each protrusion 42 protrudes substantially vertically toward the front surface 20 </ b> C side of the chamber member 20. In addition, the draft angle for enabling the die cutting at the time of resin molding is set on both side surfaces of the convex portion 42. Further, as shown in FIG. 5, the width a of the convex portion 42 and the width b of the concave portion 44 press the two convex portions 42 adjacent to each other with the leg portion 48 toward the chamber member 20 at the time of collision with a pedestrian. Each is set to do. That is, when the width of the leg portion 48 of an adult (or child) having an average physique is defined as B, two adjacent convex portions 42 when the leg portion 48 having the width B enters the gap filling portion 32 are provided. The width a of the convex portion 42 and the width b of the concave portion 44 are set so that the chamber member 20 is pressed mainly. “The two convex portions 42 are mainly” means that when the leg portions 48 enter, the two convex portions 42 are displaced toward the chamber member 20 side by substantially the same amount as the intrusion amount of the leg portions 48. Is meant to do. Accordingly, at this time, the convex portions 42 located on both sides of the two convex portions 42 are also slightly displaced toward the chamber member 20 in accordance with the displacement of the two convex portions 42, but the convex portions located outside these two convex portions 42. 42 does not contribute to the pressure change of the pressure chamber 22.

  Next, the operation and effect of this embodiment will be described.

  When the overall action is outlined, when a pedestrian collides with the center side of the front bumper 12 in the vehicle width direction, the bumper absorber 28 is elastically deformed through the bumper cover 18 to absorb energy at the time of the collision. At this time, since the gap filling portion 32 (the convex portion 42 of the concave and convex portion 46) presses the chamber member 20, the pressure in the pressure chamber 22 changes, and this pressure is changed by the first pressure sensor 24A and the second pressure sensor 24B. A change is detected. In the ECU 26, the output (P1) of the first pressure sensor 24A and the output (P2) of the second pressure sensor 24B are compared with the first threshold value Pt1 and the second threshold value Pt2, and the first detection value P1 of the first pressure sensor 24A is compared. , And any one of the second pressure detection values P2 of the second pressure sensor 24B exceeds the first threshold value Pt1, and either one of the first detection values P1 and the second pressure detection value P2 exceeds the second threshold value Pt2. If it is determined that the pedestrian has collided with the front bumper 12.

  Here, the operation and effect of the present embodiment will be described using the proportionality shown in FIGS. In addition, about the same component as this embodiment, the same number is attached | subjected and the description is abbreviate | omitted.

  6 and 7 show a case where the chamber member 20 is disposed adjacent to the front surface 14A of the bumper reinforcement 14 and the gap portion 32 is not provided (that is, the gap 36 is left as it is). Yes. In this case, when colliding with a pedestrian, the leg portion 48 of the pedestrian falls to the upper side of the bumper cover 18 while deforming the bumper cover 18 and the bumper absorber 50. For this reason, if the gap 36 exists as it is, the gap 36 becomes an idle running section when the leg part 48 of the pedestrian enters, and detection by the pressure chamber 22 may be delayed (response delay occurs). In addition, when the gap 36 exists, the leg 48 hits in an inclined state with respect to the chamber member 20, and thus there is a possibility that an accurate detection signal is not output (insufficient output) in the pressure chamber 22.

  In order to solve the above-mentioned problem, as shown in FIG. 9, assuming that the gap portion 52 in which the uneven portion 46 of this embodiment is not formed is disposed in the gap 36 (that is, the gap 36 is formed). When the leg portion 48 of the pedestrian enters the bumper absorber 54, the entire gap filling portion 52 becomes a lump and presses the chamber member 20, so that the load is dispersed. End up. Especially in a low temperature environment, the gap filling part 52 becomes hard and the rigidity becomes high. For this reason, the gap filling part 52 becomes like one rigid body and pushes the chamber member 20, so that the pressure chamber 22 becomes more difficult to detect.

  On the other hand, in this embodiment, the concavo-convex portion 46 is formed along the longitudinal direction of the chamber member 20 on the surface of the gap filling portion 32 facing the front surface 20C of the chamber member 20. For this reason, even when the outside air temperature is low and the gap filling portion 32 is cured and the rigidity of the gap filling portion 32 is increased, the entire gap filling portion 32 does not press the chamber member 20, but the uneven portion 46. The convex portion 42 presses the chamber member 20. For this reason, the collision load at the time of collision is appropriately transmitted to the pressure chamber 22. As a result, according to the present embodiment, the detection accuracy can be improved even in a low temperature environment in the configuration for detecting the collision with the pedestrian using the pressure chamber 22.

  In the present embodiment, the chamber member 20 is disposed on the upper side of the front surface 14 </ b> A that is the outer surface of the bumper reinforcement 14 in the vehicle front-rear direction. For this reason, compared with the case where the chamber member 20 is disposed on the lower side of the front surface 14A of the bumper reinforcement 14, only the collision detection with the pedestrian can be detected. That is, generally, when colliding with a pedestrian, the pedestrian falls to the upper side of the front bumper 12. On the other hand, when it collides with a pole or the like, the pole or the like falls down below the bumper cover 18. For this reason, only the collision with the pedestrian can be detected when the chamber member 20 is disposed on the upper side of the front surface 14A of the bumper reinforcement 14.

  Here, in the present embodiment, the gap portion 32 is connected to the main body portion 30 via the connection portion 38 only on the front edge side of the lower surface. In other words, the entire lower surface of the gap filling portion 32 is not connected to the main body portion 30 of the bumper absorber 28 but is connected to the main body portion 30 of the bumper absorber 28 at the front end edge of the lower surface thereof. For this reason, the gap filling portion 32 is substantially separated from the main body portion 30 of the bumper absorber 28, and the leg protection performance of the main body portion 30 is not affected. That is, the leg portion protection performance of the bumper absorber 28 is basically secured on the main body 30 side, and the hardness, dimensions, and the like of the bumper absorber 28 are set on the assumption. Therefore, when the gap filling portion 32 is connected to the main body portion 30 on the entire lower surface, the energy absorption performance of the main body portion 30 changes, which may affect the leg protection performance. However, in this embodiment, the gap filling portion 32 is configured to be connected to the main body portion 30 via the connection portion 38 only at the front edge of the lower surface, so that the influence on the main body portion 30 is minimized. Can do. As a result, according to the present embodiment, the leg protection performance of the pedestrian of the bumper absorber 28 can be maintained well.

  Furthermore, in the present embodiment, when the leg portion enters due to a collision with a pedestrian, the chamber member 20 is pressed mainly by the two convex portions 42. That is, when the leg portion 48 enters, the chamber member 20 is pressed with a volume corresponding to two protrusions with respect to the leg entry width B, so that stable output can be achieved without impairing the productivity of the bumper absorber 28. Is obtained.

  That is, if the chamber member 20 is pressed with a volume corresponding to one convex portion, the width of the convex portion (the dimension corresponding to a in FIG. 5) becomes too wide and it is difficult to press the chamber member 20 at low temperatures. There is. Conversely, when the chamber member 20 is pressed with a volume corresponding to three convex portions, a problem arises in terms of productivity. That is, since the width of the recess (the dimension corresponding to b in FIG. 5) is also narrowed, it is difficult to increase the mold strength. Further, since the width of the convex portion (the dimension corresponding to a in FIG. 5) is also narrowed, the resin material does not spread during molding. Accordingly, when the dimension is set such that the chamber member 20 is pressed with a width a corresponding to two convex portions as in the present embodiment, a stable output is obtained when the leg portion is intruded, and the productivity of the bumper absorber 28 is also kept good. Be drunk.

[Second Embodiment]
Hereinafter, a second embodiment of the pedestrian collision detection device according to the present invention will be described with reference to FIGS. Note that the same components as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIGS. 9 and 10, in the front bumper 60 as the vehicle bumper according to the second embodiment, the chamber member 62 is adjacent to the rear surface 18 </ b> C of the bumper cover 18 along the longitudinal direction of the bumper cover 18. Arranged. Note that “adjacent” here includes a case where a slight gap is formed between the chamber member 62 and the bumper cover 18 as shown in FIG. 10. Supplementally, in the case of the first embodiment described above, the chamber member 20 is disposed in contact with the front surface 14A of the bumper reinforcement 14, but in the case of the first embodiment, the design surface of the front bumper 12 is provided. Since the chamber member 20 is disposed at a position recessed from the front, there is no particular problem even if the chamber member 20 is disposed in contact with the front surface 14A of the bumper reinforcement 14. However, when the chamber member 62 is disposed next to the rear surface 18C of the bumper cover 18 as in the present embodiment, the bumper cover 18 forms a design surface, that is, the outermost member of the front bumper 60. The chamber member 62 is preferably disposed with a slight gap between the bumper cover 18 and the chamber member 62 so that an inadvertent load does not enter the bumper cover 18 and the chamber member 62 is not pushed.

  That is, the chamber member 20 is not linearly disposed adjacent to the front surface 14A of the bumper reinforcement 14 in a plan view as in the first embodiment, but the chamber member 62 has a central portion 62A in the vehicle width direction. Is formed in a curved shape that swells toward the vehicle front side from both end portions 62B, and is disposed along the bumper cover 18. For this reason, a gap 64 having the same shape as the gap 36 described in the first embodiment is formed between the center side of the rear surface 62C of the chamber member 62 and the front surface 14A of the bumper reinforcement 14. The gap 64 is formed on the center side of the front bumper 60 in the vehicle width direction, and is not formed on both end sides in the vehicle width direction.

  On the other hand, the bumper absorber 66 includes a main body 30 having the same configuration as that of the first embodiment, and a gap filling portion 68 formed integrally with the rear end portion of the main body 30. That is, as the gap 64 is formed on the bumper reinforcement 14 side, the gap filling portion 68 is also erected on the vehicle rear side end portion of the main body portion 30 and on the center side in the vehicle width direction. The gap filling portion 68 has a front surface 68 </ b> A formed in an arc shape that matches the curvature of the rear surface 62 </ b> C of the chamber member 62, and a rear surface 68 </ b> B formed in a flat shape that matches the shape of the front surface 14 </ b> A of the bumper reinforcement 14. The gap filling portion 68 is disposed in the gap 64. Note that the concave and convex portion 46 as in the first embodiment described above is not formed on the front surface 68A of the gap filling portion 68. Further, as shown in FIG. 11, both end portions 62B of the chamber member 62 in the vehicle width direction are disposed adjacent to the front surface 14A of the bumper reinforcement 14 without interposing the gap filling portion 68 therebetween. .

(Action / Effect)
According to the above configuration, since the chamber member 62 is disposed along the bumper cover 18 adjacent to the rear surface 18C of the bumper cover 18, the collision load with the pedestrian is directly transmitted to the pressure chamber 22. For this reason, compared with the case where the collision load with the pedestrian is transmitted to the chamber member 20 via the bumper absorber 28 as in the first embodiment described above, the detection accuracy is increased.

  However, since the bumper cover 18 has a shape in which the central portion 18A in the vehicle width direction swells toward the front side of the vehicle with respect to the both end portions 18B, the chamber having the same planar shape as the bumper cover 18 along the bumper cover 18. When the member 62 is disposed, the collision load with the leg part of the pedestrian tends to increase on the central part 18A side of the bumper cover 18. Conversely, the both end portions 18B of the bumper cover 18 have an angle with respect to the vehicle width direction when viewed in a plan view (both end portions 18B of the bumper cover 18 in the vehicle width direction are inclined with respect to the central portion 18A). Therefore, the collision load with the pedestrian leg 48 tends to be small.

  On the other hand, in the present embodiment, since the gap filling portion 68 is disposed on the side of the central portion 18A in the vehicle width direction of the bumper cover 18, the collision load is reduced by elastic deformation of the gap filling portion 68. For this reason, a good load is transmitted to the pressure chamber 22. Further, the gap filling portion 68 does not exist adjacent to the rear surface 62C of the chamber member 62 on the both end portions 18B side of the bumper cover 18 in the vehicle width direction. That is, the front surface 14 </ b> A of the bumper reinforcement 14 is disposed adjacent to the bumper reinforcement 14. For this reason, since the chamber member 62 is supported by the front surface 14A of the bumper reinforcement 14, a load (reaction force) is also transmitted from the front surface 14A of the bumper reinforcement 14 to the pressure chamber 22. Therefore, an appropriate collision load is transmitted to the pressure chamber 22 even when the chamber member 62 collides with a pedestrian on both ends 62B in the vehicle width direction. As a result, according to the present embodiment, variations in detection accuracy of pedestrian collision by the chamber member 62 are eliminated or reduced, and substantially uniform detection accuracy can be ensured in the vehicle width direction. Therefore, according to this embodiment, the detection accuracy of a pedestrian collision can be improved in that sense.

[Supplementary explanation of the above embodiment]
In the above-described embodiment, an example in which the ECU 26 determines a collision using a pressure waveform as the detection value P of the pressure sensor 24 has been described. However, the present invention is not limited to this, and the pressure of the chamber member 20 is changed to other physical quantities. You may make it determine a collision using the detected value converted into etc. FIG. Therefore, for example, the collision may be determined using the effective mass (m) obtained from the output signal (pressure waveform) of the pressure sensor 24 as the detection value (M). Further, for example, the collision may be determined using a detection value obtained by simply integrating the pressure waveform (detection value P) over time.

  In the above-described embodiment, the example in which the collision determination system 10 is applied to the front bumper 12 has been described. However, the present invention is not limited to this, and for example, the above configuration may be reversed and applied to the rear bumper. Good.

10 Collision determination system (pedestrian collision detection device)
12 Front bumper (vehicle bumper)
14 Bumper reinforcement 14A Front (outer side in the vehicle longitudinal direction)
18 Bumper cover 18A Central part 18B Both ends 20 Chamber member 22 Pressure chamber 24 Pressure sensor (pressure detector)
24A first pressure sensor (pressure detector)
24B Second pressure sensor (pressure detector)
26 ECU (collision determination unit)
28 Bumper absorber 30 Main body portion 32 Gap filling portion 36 Clearance 38 Connection portion 42 Convex portion 44 Concavity portion 46 Concavity and convexity portion 60 Front bumper (bumper for vehicle)
62 Chamber member 62A Central part 62B Both ends 64 Crevice 66 Bumper absorber 68 Gap filling part

Claims (4)

Bumper reinforcement arranged with the vehicle width direction as the longitudinal direction;
The bumper reinforcement is arranged on the outside in the vehicle front-rear direction and is arranged along the bumper reinforcement with the vehicle width direction as the longitudinal direction, and the center in the vehicle width direction is more outward in the vehicle front-rear direction than both ends in plan view. A swollen bumper cover,
A bumper absorber for energy absorption that is interposed between the bumper cover and the bumper reinforcement and is arranged with the vehicle width direction as a longitudinal direction;
Applied to a vehicle bumper composed of
A chamber member disposed adjacent to an outer surface of the bumper reinforcement in the vehicle front-rear direction and disposed along the bumper reinforcement with the vehicle width direction as a longitudinal direction, and the inside being a pressure chamber;
A pressure detector disposed inside the front and rear direction of the chamber member for outputting a signal corresponding to a pressure change in the pressure chamber;
A collision determination unit that determines whether or not a collision has occurred with a pedestrian based on the output of the pressure detector;
The bumper absorber is provided on the vehicle width direction center side, and is provided so as to be packed in a gap between the outer side surface of the chamber member in the vehicle front-rear direction and the inner side surface of the bumper cover in the vehicle front-rear direction in plan view A gap filling portion in which a concavo-convex portion is formed along the longitudinal direction of the chamber member on a surface facing the outer surface of the chamber member in the vehicle front-rear direction,
A pedestrian collision detection device. The chamber member is disposed on an upper portion of an outer side surface in the vehicle front-rear direction in the bumper reinforcement,
The bumper absorber is configured to include the gap filling portion and a main body portion disposed at a lower portion of an outer side surface of the bumper reinforcement in the vehicle front-rear direction, and a part of a lower surface of the gap filling portion is further formed. Connected to the main unit,
The pedestrian collision detection apparatus according to claim 1. The width of the convex part and the concave part of the concavo-convex part is set so that the chamber member is pressed mainly by two adjacent convex parts at the time of leg intrusion due to a collision with a pedestrian,
The pedestrian collision detection device according to claim 1 or 2. Bumper reinforcement arranged with the vehicle width direction as the longitudinal direction;
The bumper reinforcement is arranged on the outside in the vehicle front-rear direction and is arranged along the bumper reinforcement with the vehicle width direction as the longitudinal direction, and the center in the vehicle width direction is more outward in the vehicle front-rear direction than both ends in plan view. A swollen bumper cover,
A bumper absorber for energy absorption that is interposed between the bumper cover and the bumper reinforcement and is arranged with the vehicle width direction as a longitudinal direction;
Applied to a vehicle bumper composed of
The bumper cover is arranged along the bumper cover adjacent to the inner side surface in the vehicle front-rear direction, and the center part in the vehicle width direction is formed in a shape bulging outward in the vehicle front-rear direction from both ends in plan view, and A chamber member whose inside is a pressure chamber;
A pressure detector disposed inside the front and rear direction of the chamber member for outputting a signal corresponding to a pressure change in the pressure chamber;
A collision determination unit that determines whether or not a collision has occurred with a pedestrian based on the output of the pressure detector;
The bumper absorber is provided on the center side in the vehicle width direction, and is provided so as to be packed in a gap between the inner side surface of the chamber member in the vehicle front-rear direction and the outer side surface of the bumper reinforcement in the vehicle front-rear direction in plan view. A gap portion,
A pedestrian collision detection device.

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