JP2007076478A - Arrangement structure of energy absorbing member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an arrangement structure of an energy absorbing member capable of constantly securing a specified quantity or more of energy absorbing capacity regardless of the collision position of a pedestrian in a collision surface. <P>SOLUTION: This arrangement structure of the energy absorbing member is provided on the back side of a collided surface B of a hood, etc. of a vehicle and reduces impact which a pedestrian H receives from the collided surface B in collision with the pedestrian H, the energy absorbing member 12 is positioned at each of intersections of a virtual triangular grid, length between the adjacent energy absorbing members 12, 12 is decided in dependence on thickness of the energy absorbing member 12, and, consequently, at least more than one energy absorbing members 12 correspond to a colliding position of the pedestrian H until the collided surface B sunk and deformed by collision of the pedestrian H reaches the amount of the thickness of the energy absorbing member 12 when the pedestrian H collides against the collided surface B. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an arrangement structure of an energy absorbing member that suitably absorbs energy related to a collision of a pedestrian and a vehicle with a hood or the like at the time of an accident between the pedestrian and the vehicle.

  For example, when a pedestrian contacts the front part of the automobile, the pedestrian is likely to contact the hood. That is, the pedestrian is jumped up by the collision force at the time of the accident and falls from the head onto the hood. In addition, bonnets are becoming thinner due to recent demands for automobiles such as lighter weight and improved design. Under the bonnet, components such as the engine body and its accessories, suspension turrets, scuttle panels, hinges, etc. High-rigidity parts are arranged. For this reason, the request | requirement which reduces the damage (impact) received when the accident which a pedestrian contacts the front part of a motor vehicle has increased.

  By the way, the performance of an energy absorber that absorbs normal impacts is the energy absorption capacity secured by its own structure and material, the area that can receive energy (hereinafter referred to as impact receiving area), and its thickness. (It is thought that it depends on the amount of deformation (stroke) that can sink when absorbing shock. On the back side of the hood of a general automobile, there is a soundproofing material provided to reduce noise from the engine room, The impact receiving area is sufficient because it exists over almost the entire bonnet, but it is not sufficient in terms of energy absorption capacity because the purpose of use is different.

  Therefore, in order to give a good energy absorption capability to the bonnet having such a structure, an energy absorption member having a high energy absorption capability may be disposed inside the soundproof material. However, in places where the space is limited, such as the back of the bonnet, priority is given to maintaining the soundproofing performance by the soundproofing material and avoiding it as much as possible, so the number of energy absorbing members must be minimized. There is a need to. Similarly, with respect to the arrangement position, there are large restrictions on the layout and the like, and it is difficult to suitably arrange an energy absorbing member having high energy absorption ability.

  The present invention has been proposed in view of the problems associated with the prior art, and has been proposed to suitably solve this problem.In the event of an accident or the like, the pedestrian always sinks and deforms due to the pedestrian's collision. By the collision surface reaching the thickness of the energy absorbing member, the impact receiving surface has a total area of a certain level or more, ensuring a certain level of energy absorbing ability regardless of the collision position, and the impact received by the pedestrian An object of the present invention is to provide an arrangement structure of energy absorbing members that can reduce the above.

In order to overcome the above problems and achieve the intended purpose, the invention according to claim 1
An arrangement structure of an energy absorbing member that is provided on the back side of a collision target surface such as a bonnet of a vehicle, and reduces an impact that the pedestrian receives from the collision target surface in a collision with a pedestrian,
The gist is that the energy absorbing member is located at each intersection of the virtual triangular lattice, and the length between the adjacent energy absorbing members is determined depending on the thickness of the energy absorbing member.

  Therefore, according to the first aspect of the present invention, even when the space such as the back of the bonnet is greatly restricted and the energy absorbing member is not disposed over the entire impacted surface in order to maintain the soundproofing performance by the soundproofing material. , For a pedestrian that collides with the collided surface, the collided surface that sinks and deforms due to the collision of the pedestrian reaches the thickness of the energy absorbing member, and one or more of the above When the energy absorbing member corresponds to the collision position of the pedestrian, an energy absorbing member arrangement structure that can ensure an energy absorbing ability of a certain level or more and can suitably reduce the impact regardless of the collision position can be achieved.

In order to overcome the above problems and achieve the intended purpose, the invention according to claim 2
An arrangement structure of an energy absorbing member that is provided on the back side of a collision target surface such as a hood of a vehicle and reduces an impact that the pedestrian receives from the collision surface at the time of a collision with a pedestrian,
The energy absorbing member is located at each intersection of the virtual triangular lattice, and the length between the adjacent energy absorbing members is determined depending on the thickness of the energy absorbing member,
As a result, when the pedestrian collides with the collision surface, the collision target surface that sinks and deforms due to the collision of the pedestrian reaches the thickness of the energy absorbing member, and at least one or more The gist of the invention is that the energy absorbing member corresponds to the collision position of the pedestrian.

  Therefore, according to the second aspect of the present invention, even when the space such as the back of the bonnet is greatly restricted and the energy absorbing member is not disposed over the entire impacted surface in order to maintain the soundproofing performance of the soundproofing material. , For a pedestrian that collides with the collided surface, the collided surface that sinks and deforms due to the collision of the pedestrian reaches the thickness of the energy absorbing member, and one or more of the above When the energy absorbing member corresponds to the collision position of the pedestrian, an energy absorbing member arrangement structure that can ensure an energy absorbing ability of a certain level or more and can suitably reduce the impact regardless of the collision position can be achieved.

従って、請求項３に係る発明によれば、エネルギー吸収部材の厚さに拘わらず、効率的にエネルギー吸収部材の配置をすることができる。 The invention according to claim 3 is the invention according to claim 1 or 2, wherein the length between the energy absorbing members is the following [several A], where D is the thickness of the energy absorbing member. The gist is that the value is not more than the value calculated from the above.

Therefore, according to the invention which concerns on Claim 3, regardless of the thickness of an energy absorption member, an energy absorption member can be arrange | positioned efficiently.

  The gist of the invention according to claim 4 is that, in the invention according to any one of claims 1 to 3, the individual triangles forming the virtual triangular lattice are regular triangles. Therefore, according to the invention according to claim 4, since the energy absorbing member can be regularly arranged with respect to the collision surface, for example, it is easy to combine with the soundproofing material on the back of the bonnet, etc. Can be reduced.

  The gist of the invention according to claim 5 is that, in the invention according to any one of claims 1 to 4, the impact receiving surface of the energy absorbing member is substantially circular. Therefore, according to the invention which concerns on Claim 5, the reduction of the impact when a pedestrian collides with a to-be-collised surface can be homogenized.

  The invention according to claim 6 is the invention according to any one of claims 1 to 5, wherein the energy absorbing member is submerged and deformed by the collision of the pedestrian, regardless of the collision position of the pedestrian. By the time the collision surface reaches the thickness of the energy absorbing member, the total area of the impact receiving surface in the energy absorbing member corresponding to the collision position of the pedestrian secures the area of at least one impact receiving surface. The gist is that they are arranged as described above. Therefore, according to the invention which concerns on Claim 6, more than fixed impact can be reduced irrespective of the collision site | part.

According to a seventh aspect of the invention, in the invention of the sixth aspect, in order to secure the total area of the impact receiving surface, the length between the energy absorbing members is set to the thickness D of the energy absorbing member [several B By using R calculated by substituting for [alpha] and [alpha] represented by the following [number C], the gist is that it is calculated as L satisfying the following [number D].

  Therefore, according to the invention which concerns on Claim 7, regardless of the collision position, arrangement | positioning of the energy absorption member which absorbs an impact suitably can be calculated.

  As described above, according to the arrangement structure of the energy absorbing member of the present invention, it is possible to always ensure a certain level of energy absorbing ability regardless of the collision position of the pedestrian on the collision target surface.

  Next, the arrangement structure of the energy absorbing member according to the present invention will be described below with reference to the accompanying drawings by giving a preferred embodiment. The inventor of the present application arranges the energy absorbing member so as to be positioned at each intersection of the virtual triangular lattice, so that when the pedestrian collides with the hood or the like of the automobile, the energy absorbing member is placed at the collision position with fewer energy absorbing members. In spite of this, the present inventors have found an arrangement structure of energy absorbing members that can reduce the impact received by a pedestrian. In addition, regarding the arrangement of the energy absorbing member, the length between the energy absorbing members is calculated from the thickness of the energy absorbing member, so that it can be suitably handled regardless of the thickness of the arranged energy absorbing member. Can do. In addition, when the energy absorbing member is positioned at each intersection of the virtual triangular lattice, the three energy absorbing members adjacent to each other are arranged at each vertex of the virtual triangle.

  In order to contribute to understanding the arrangement structure of the energy absorbing member according to the embodiment, the “pedestrian head protection performance test” is one method for measuring and evaluating the impact received by the pedestrian at the time of a collision between the pedestrian and the automobile. Will be described. In the performance test, as shown in FIG. 1, an adult or a child, assuming that the vehicle hits the pedestrian H at a constant speed and the head of the pedestrian H collided with the hood and front window of the vehicle. A dummy (head impactor) simulating the head of (pedestrian H) is fired from a testing machine to the bonnet or the like, and the impact received by the dummy is measured and evaluated as a head injury value (HIC). The dummy firing speed is set to 32 km / h (the collision speed of the car against the pedestrian H is equivalent to 40 km / h). Here, as the dummy, one having a diameter (2T): 165 mm (weight, adult: 4.5 kg, child: 3.5 kg) is used (see FIG. 1B). From such a background, when a pedestrian and a car collide in the following description, the expression of the pedestrian is assumed to indicate its head in a broad sense.

  As shown in FIG. 2, the energy absorbing members 12 according to the embodiment have a predetermined pattern behind a bonnet or the like (hereinafter referred to as a collision surface B) that the pedestrian H collides with in the event of an automobile. It is a member that is disposed and absorbs energy related to collision by destroying its own structure and the like, and reduces the impact received by pedestrian H. In this embodiment, as shown in FIG. 3, the energy absorbing member 12 is a cylindrical object in which the shape of the impact receiving surface 12a (surface) that receives the collision of the pedestrian H is a circle having a diameter (2r): 25 mm. . And as the material, a rigid polyurethane foam having a structure that absorbs energy by destroying its shape (here, foam skeleton) is adopted and disposed along with the soundproofing material on the back of the hood. In the present invention, the portion of the impact receiving surface 12a of the energy absorbing member 12 that overlaps with the impactor when viewed from the direction in which the impactor (the head of the pedestrian H) flies is referred to as a corresponding portion. The total area of the corresponding portion, that is, the portion that can receive the impact of the pedestrian H (impactor) is referred to as the total impact receiving surface area.

  Here, as described above, the size of the impact receiving surface 12a is a circle having a diameter (2r) of 25 mm. By setting the shape to be circular, an arrangement dimension to be described later ([0023]) is suitably determined. As for the size, if the diameter (2r) is about 25 mm, the bonnet and the like can be suitably arranged without affecting the soundproofing material, etc., but energy absorption is accompanied by the increase in size. In order to improve the performance, it is needless to say that it should be as large as possible within the range permitted by the arrangement environment of other members at the arrangement position.

  In addition, the shape is preferably a circular shape in which a spread in all directions is ensured from a required one point, but may be an elliptical shape or other shapes. The distance (L) between the energy absorbing members 12 and 12 (between the centers of the energy absorbing members 12) is 107.7 mm or less (the thickness (D) of the energy absorbing member 12 is 20 mm), which will be described later ([0025]). In the present embodiment). This is because the distance (L) between the energy absorbing members 12 and 12 is a circle formed on the collision surface B when the dummy collides with the collision surface B (collision area (described later [0024])). The diameter (2R) of the pedestrian is equal to or less, and under this condition, the impact received by the pedestrian H can be reduced no matter what position the pedestrian H (its head) contacts. .

  The plurality of energy absorbing members 12 are arranged so that the pedestrian H, that is, a flying dummy can be received by the impact receiving surface 12a. As shown in FIGS. 2 and 4, the energy absorbing member 12 is located at the intersection of the virtual triangular lattice. An imaginary line connecting three adjacent energy absorbing members 12, 12, 12 forms a triangular lattice of equilateral triangles, and the length of one side thereof, that is, the distance (L) between the energy absorbing members 12, 12 is As described above, it is 107.7 mm or less. As described above, by arranging the plurality of energy absorbing members 12 as described above, it is possible to efficiently cover a certain region with fewer energy absorbing members 12 compared to other arrangement structures.

  Here, the dimension in which the energy absorbing member 12 is arranged, that is, the distance (L) between the energy absorbing members 12 and 12 is determined when the pedestrian H (head) collides with the collision target surface B. The impacted surface B that sinks and deforms due to the collision is determined so that the impact (energy related to the collision) received by the pedestrian H can be suitably reduced before reaching the thickness (D) of the energy absorbing member 12. The On the other hand, the relationship between the pedestrian H and the energy absorbing member 12 on the collision target surface B is in any form shown in FIG. Specifically, when pedestrian H collides with only one energy absorbing member 12 (see FIG. 5A), when pedestrian H collides with two energy absorbing members 12 (see FIG. 5B). ) Or a case where a pedestrian H collides with three energy absorbing members 12 (see FIG. 5C). In FIG. 5, the hatched portion is a gait that has collided via the collision target surface B (bonnet) and has been depressed and submerged by the thickness (D) of the energy absorbing member 12. The corresponding part which overlaps with the person H and the impact receiving surface 12a, ie, the part which can directly absorb the impact of contact between the pedestrian H and the collision target surface B is indicated. In these three typical three patterns, the form in which the collision surface B of the pedestrian H (the head) is most easily separated from the three energy absorbing members 12 forming the triangular lattice is the pedestrian H ( The center of the head is the most distant from the three energy absorbing members 12 forming a triangular lattice.

Therefore, the center of the pedestrian H (head) is an outer center of a region ((regular) triangle) formed with the centers of the three energy absorbing members 12 (impact receiving surface 12a) shown in FIG. When the pedestrian H (the head) is located at (center of the circumscribed circle) and sinks due to the thickness (D) of the energy absorbing member 12 and dents and sinks (stroke), the energy absorbing member 12 is always The arrangement size of the energy absorbing member 12 is determined so as to have overlapping corresponding portions. On the other hand, the contact (collision) region when the pedestrian H (the head) collides with the collision surface B is assumed to have a thickness (D) of the energy absorbing member 12 of 20 mm which is a numerical value in a general bonnet or the like. However, as shown in FIG. 6, when the impacted surface B is recessed (deformed) by the impact due to the collision, that is, the impacted surface B is deformed by the impact of the pedestrian H (head). However, it is determined on the assumption that the energy absorbing member 12 is submerged (stroked) by the thickness (D). As a result, the collision area of the head (dummy) having a diameter of 165 mm with the collision surface B is circular, and the diameter (2R) is calculated from the following [Numerical Formula A] to be 107.7 mm.

  From these conditions, the length of one side of the equilateral triangle (distance (L) between the energy absorbing members 12, 12) is a circle with a diameter (2R): 107.7 mm, and the three circles shown in FIG. When the energy absorbing members 12, 12, 12 are positioned at the outer center of an equilateral triangle formed with each vertex, the impact receiving surface 12 a is determined so as to surely have a corresponding portion. Specifically, it is at least 107.7 mm or less as described above. In this case, the impacted surface B is dented and deformed by contact with the pedestrian H, and the impact received by the pedestrian H inevitably absorbs energy until it sinks (strokes) by the thickness (D) of the energy absorbing member 12. It will be absorbed by the member 12. Therefore, even if the pedestrian H collides with any position on the collision target surface B, the energy related to the collision is always absorbed, and the impact received by the pedestrian H is reduced.

ここでＲは以下の[数Ｂ]によって、αは以下の[数Ｃ]で定義される。

また一つ分の衝撃受面１２ａの面積は、その半径がｒ(本実施例では２ｒ＝２５ｍｍより、ｒ＝１２.５ｍｍ)であるためπｒ^２から算出される。従って、以下の[数Ｄ]が導出される。

In addition, the distance (L) between the two energy absorbing members 12 and 12 is a numerical value calculated from [number A] in the largest case, but there is no problem even if it is less than this. In particular, in any of the three typical cases described with reference to FIG. 5, the area of the impact receiving surface 12a provided by the at least one energy absorbing member 12 is secured as the total impact receiving surface area. It is desirable. Thus, when the pedestrian H collides with the collision target surface B, the overlap (corresponding portion) area between the pedestrian H and one energy absorbing member 12 is calculated by the following [Equation 1].

Here, R is defined by the following [Equation B], and α is defined by the following [Equation C].

The area of one impact receiving surface 12a is calculated from πr ² because the radius is r (in this embodiment, 2r = 25 mm, r = 12.5 mm). Therefore, the following [number D] is derived.

  If L calculated to satisfy this [number D] is the distance between the energy absorbing members 12, 12, the collision of the pedestrian H will occur in any of the three typical cases described in FIG. At least one area of the impact receiving surface 12a is ensured as the total area of the impact receiving surface in the energy absorbing member 12 corresponding to the position. Here, R is the radius of a circle formed on the impacted surface B when the dummy that collides with the impacted surface B sinks (strokes) by the thickness (D) of the energy absorbing member 12. , [Equation A], which is about 53.85 mm in this embodiment.

  Actually, when L is calculated from [number D] under the conditions of the present embodiment, L ≦ 98.13 mm. That is, when the distance (L) between the energy absorbing members 12 and 12 is 107.7 mm, as shown in FIG. 7, the total impact receiving surface area (S) is the area of the impact receiving surface 12a (E ) Is about 30% (see FIG. 7A), but when L is reduced and the adjacent energy absorbing members 12, 12 are brought close to 98.13 mm, S = E (FIG. 7 ( b)), and if it is less than 98.13 mm, S ≧ E (see FIG. 7C).

なお[数Ｄ]および[数Ｅ]において、角度はＤｅｇｒｅｅで表示されている。 In addition, [Numerical formula D] is out of order when the distance (L) between the energy absorbing members 12 and 12 falls below a certain value, and it is necessary to use the following [Numerical formula E]. If there are any, it is sufficient to apply [number D], so a detailed description is omitted.

Note that in [Numerical formula D] and [Numerical formula E], the angle is displayed in Degree.

  Here, the thickness (D) of the energy absorbing member 12 is 20 mm. However, since [Equation B] and [Equation D] are both variables, for example, the thickness (D of the energy absorbing member 12 that can be arranged due to the difference in the vehicle type, specifically, the general sedan, SUV, or the like. ) Can be calculated, the preferred distance (L) between the energy absorbing members 12, 12 can be calculated. For example, when the thickness (D) of the energy absorbing member 12 is set to 35 mm, the distance (L) between the energy absorbing members 12 and 12 is 134.9 mm (see [Numerical Formula A]) or less, and preferably 121.80 mm. (See [Equation D])

  In addition, since the energy absorbing member 12 does not need to be disposed in the entire area of the bonnet or the like, the arrangement of the sound insulating material or the like having the effect of sound insulation or the like that has been applied to the bonnet or the like, the design of the bonnet itself, There is no hindrance. As described above, the present embodiment can be easily implemented by applying a member to a part of the colliding surface B such as a bonnet, and therefore can be easily implemented even for an already used automobile. Costs and installation costs can also be reduced.

(Example of change)
In addition, in the above-described embodiment, the three energy absorbing members 12, 12, 12 are arranged on the vertex of the equilateral triangle on the collision target surface B, but the present invention is not limited to this. Absent. For example, the arrangement position of the energy absorbing members 12 arranged as shown in FIG. 8 is shifted so that the distance between some of the two energy absorbing members 12 and 12 is 107.7 mm or less (here, about 86 mm). It may be. Furthermore, the length of each side of the region (triangle) formed by the three energy absorbing members 12, 12, 12 may be different from each other.

  In the above-described embodiment, the size of the impact receiving surface 12a of the energy absorbing member 12 is 25 mm or more. However, even if the diameter (2r) is small, the energy absorbing ability of one energy absorbing member 12 is small. If there is sufficient, the diameter may be 25 mm or less. Even in this case, in [Equation C] and [Equation D], since r is a variable, calculation relating to a suitable arrangement is possible.

(Another example)
In the above-described embodiment, the case where the material is a hard polyurethane foam having a structure that absorbs energy by breaking the shape of the energy absorbing member 12 is described. Any material and structure that expresses can be used. For example, a plastic plate having a certain thickness is processed into a three-dimensional shape such as a columnar shape, a truncated cone shape that opens downward, an inverted truncated pyramid shape, a conical sphere shape, or a hemispherical shape (both inside are hollow) and used. You may do it. In this case, energy related to the collision of the pedestrian H is absorbed by the three-dimensional structure of the cylindrical object being destroyed by the collision of the pedestrian.

It is explanatory drawing which showed the dimension of the dummy etc. which are used for the pedestrian head protection performance test which evaluates the energy absorption member which concerns on the preferred Example of this invention, and this test. It is the schematic which shows the arrangement structure of the energy absorption member which concerns on an Example. It is the schematic which shows the energy absorption member which concerns on an Example. It is explanatory drawing which shows the arrangement structure of the energy absorption member in a colliding surface in detail. It is the schematic which shows the positional relationship of this pedestrian and an energy absorption member when a pedestrian collides with a to-be-collised surface. When the pedestrian collides with the collision surface, the state of deformation of the collision surface by the pedestrian (head) and the collision area between the pedestrian (head) and the collision surface at that time FIG. It is the schematic which shows the change of the impact receiving surface total area by the change of the distance between energy absorption members. It is explanatory drawing which shows the arrangement structure of the energy absorption member in the colliding surface which concerns on the example of a change in detail.

Explanation of symbols

12 Energy absorbing member, 12a Impact receiving surface, B Colliding surface, H Pedestrian

Claims (7)

An energy absorbing member that is provided on the back side of a collision target surface (B) such as a bonnet of a vehicle and reduces an impact that the pedestrian (H) receives from the collision target surface (B) in the case of a collision with the pedestrian (H). The arrangement structure of
The energy absorbing member (12) is located at each intersection of the virtual triangular lattice, and the length between the adjacent energy absorbing members (12, 12) depends on the thickness of the energy absorbing member (12). The arrangement structure of the energy absorbing member, characterized by being determined. An energy absorbing member that is provided on the back side of a collision target surface (B) such as a bonnet of a vehicle and reduces an impact that the pedestrian (H) receives from the collision target surface (B) in the case of a collision with the pedestrian (H). The arrangement structure of
The energy absorbing member (12) is located at each intersection of the virtual triangular lattice, and the length between the adjacent energy absorbing members (12, 12) depends on the thickness of the energy absorbing member (12). Determined,
As a result, when the pedestrian (H) collides with the impacted surface (B), the impacted surface (B) that sinks and deforms due to the collision of the pedestrian (H) is transformed into the energy absorbing member (12). The arrangement structure of the energy absorbing member, wherein at least one of the energy absorbing members (12) corresponds to the collision position of the pedestrian (H) before reaching the thickness. The length between the energy absorbing members (12, 12) is set to be equal to or less than a value calculated from the following [Numerical Formula A], where D is the thickness of the energy absorbing member (12). Or the arrangement structure of the energy absorption member of 2.

  The arrangement structure of the energy absorbing member according to claim 1, wherein each triangle forming the virtual triangular lattice is a regular triangle.   The energy absorbing member arrangement structure according to any one of claims 1 to 4, wherein the impact receiving surface (12a) of the energy absorbing member (12) is substantially circular.   The energy absorbing member (12), regardless of the collision position of the pedestrian (H), the impacted surface (B) that sinks and deforms due to the collision of the pedestrian (H), the energy absorbing member (12) The total area of the impact receiving surface in the energy absorbing member (12) corresponding to the collision position of the pedestrian (H) is secured to the area of at least one impact receiving surface (12a). The arrangement structure of the energy absorbing member according to any one of claims 1 to 5, wherein the energy absorbing member is arranged so as to do so. In order to secure the total area of the impact receiving surface, the length between the energy absorbing members (12, 12) is calculated by substituting the thickness D of the energy absorbing member (12) into [number B]. The arrangement structure of the energy absorbing member according to claim 6 calculated as L satisfying the following [Numerical formula D] by using the following [Numerical formula C].

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