JP2009168109A - Ea material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an EA material made of a foamed resin molding of a hard polyurethane foam and the like that absorbs a large amount of energy and eases impact sufficiently. <P>SOLUTION: The EA material 1 consists of an EA material main body 2 made of a foamed resin molding of a hard polyurethane foam and the like and reinforcement members 3 embedded in the EA material main body 2. The reinforcement members 3 are of a cylindrical shape and keep the direction of the axial center of the cylindrical shape in the fore and aft direction of the EA material. Many openings may be provided in the wall of the cylindrical shape of the reinforcement members 3. The reinforcement members 3 may be structured with meshes. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to an attachment structure for an EA material (impact energy absorbing material), and more particularly to an attachment structure for an EA material suitable for application to an automobile trim or the like.

  An EA material made of rigid urethane foam is attached to a door trim of an automobile for energy absorption (EA) at the time of a side collision (side collision).

  The stress-strain curve of this EA material rises rapidly with increasing strain in a small strain range as shown in a, rather than a straight line as shown in b of FIG. It is preferable to have an inverted S-shaped characteristic that does not increase much as the stress value increases.

The EA material having the inverted S-shaped stress-strain characteristic (a) has a larger amount of energy absorption than the EA material having the substantially linear characteristic (b), and the impact applied to the vehicle occupant is large. This is sufficiently relaxed (for example, JP-A-5-331364).
JP-A-5-331364

  An object of this invention is to provide the EA material which consists of foaming resin moldings, such as a rigid polyurethane foam with much energy absorption amount and a low impact value.

  The EA material according to claim 1 is an EA material having an EA material body made of a foamed resin molded body having a front surface for receiving an object and a rear surface opposite to the front surface, in a direction connecting the front surface and the rear surface. The extended reinforcing member is embedded in the EA material main body.

  The EA material according to claim 2 is characterized in that, in claim 1, the foamed resin molded body is made of a rigid polyurethane foam.

  The EA material according to claim 3 is characterized in that, in claim 1 or 2, the reinforcing member is a cylindrical body and is embedded with the axial direction of the cylinder being the front-rear direction.

  The EA material of claim 4 is characterized in that, in claim 3, an opening is provided in the cylindrical wall portion of the cylindrical body so as to communicate the inner side and the outer side of the cylinder.

  The EA material of claim 5 is characterized in that, in claim 3 or 4, the cylindrical body is made of a mesh.

  In the EA material of the present invention, the reinforcing member is embedded in the foamed resin molded body, the stress-strain characteristic becomes an inverted S shape, the energy absorption amount is large, and the impact is sufficiently mitigated. It becomes like this.

  Rigid polyurethane foam is suitable as the foamed resin molding.

  The reinforcing member is preferably formed of a cylindrical body and embedded so that the axial direction of the cylinder is the front-rear direction.

  By providing an opening that communicates the inside and outside of the tubular body, the integrity of the foamed resin molded body on the inside of the tubular body and the foamed resin molded body on the outside is improved, and the characteristics of the EA material Will improve. Such a cylindrical body may be made of a mesh.

  Hereinafter, embodiments will be described with reference to the drawings.

  FIG. 1 is a perspective view of an EA material according to the embodiment, and FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 3 and 4 are perspective views of an EA material according to another embodiment, and FIGS. 5 to 10 are configuration diagrams of reinforcing members, respectively. FIG. 11 is a stress-strain curve diagram of the EA material as described above.

  An EA material 1 shown in FIGS. 1 and 2 includes an EA material main body 2 made of a foamed resin molded body such as a rigid polyurethane foam, and a reinforcing member 3 embedded in the EA material main body 2. In this embodiment, the EA material body 2 has a disk shape having a front surface 2a and a rear surface 2b that are substantially parallel. As shown in FIG. 5, the reinforcing member 3 has a cylindrical shape, and the cylinder axis direction is the front-rear direction of the EA material (the direction connecting the front surface 2a and the rear surface 2b. In this embodiment, the direction perpendicular to the rear surface 2b. ).

  The rear end of the reinforcing member 3 may reach the rear surface 2b or may be slightly separated from the rear surface.

  In this embodiment, two reinforcing members 3 are provided, but may be appropriately selected according to the size of the EA material 1 and the size of the reinforcing member 3. A suitable material for the reinforcing member 3 will be described later.

  In the EA material 1 having the reinforcing member 3, the reinforcing member 3 is placed in a mold for forming the EA material main body 2, the urethane stock solution is supplied, the mold is clamped, foamed, cured, and then removed. Just type. When the reinforcing member 3 is disposed in the mold, it is preferable to fix the reinforcing member 3 using a fastening tool such as a clip or a locking portion provided on the inner surface of the mold. A magnet may be provided on at least one of the reinforcing member 3 and the cavity surface, a magnetic material portion may be provided on the other, and the reinforcing member 3 may be fixed to the mold using magnetic force.

  By embedding such a reinforcing member 3 in the EA material main body 2, the stress-strain characteristic of the EA material becomes the curve a shown in FIG. Therefore, as compared with the conventional product having the characteristic indicated by the curve b without the reinforcing member 3, the impact energy absorption amount of the EA material is increased and the impact is sufficiently mitigated.

  The EA material 4 in FIG. 3 has a disk-shaped EA material main body 5 made of a foamed resin molded body, and a reinforcing member 6 embedded in the EA material main body 5. As shown in FIG. 9, the reinforcing member 6 is formed of a cylindrical body whose cross section perpendicular to the axial direction of the cylinder is oval or elliptical. Other configurations are the same as those in FIGS.

  The EA material 7 in FIG. 4 includes an EA material main body 8 made of a foamed resin molded body and a reinforcing member 9 embedded in the EA material main body 8. The EA material body 8 has a flat rear surface 8d and stepped front surfaces 8a, 8b, and 8c.

  Each of the front surfaces 8a, 8b, and 8c is substantially parallel to the rear surface 8d, the front surface 8a is a low step portion closest to the rear surface 8d, the front surface 8c is a high step portion that is most separated from the rear surface 8d, and the front surface 8b is both It is the middle part of the middle. The cylindrical body 9 is cylindrical and has a cylindrical axis direction perpendicular to the rear surface 8d. The cylindrical body 9 is disposed on the inner side of the front surface 8c. The front end of the cylindrical body 9 is buried by the distance t from the front surface 8c. The rear end of the cylindrical body 9 is flush with the rear surface 8d or is slightly buried.

  In this embodiment, the cylindrical body 9 is disposed only on the front surface 8c portion, but may also be disposed on the front surface 8a and 8b portions.

  These EA materials 4 and 7 also have reverse S-shaped stress-strain characteristics shown in FIG. 11a, and exhibit excellent shock absorption characteristics.

  Next, still another preferred example of the reinforcing member will be described.

  The reinforcing members 3 and 6 shown in FIGS. 5 and 9 are cylindrical and oval (or elliptical) cylindrical, but the triangular cylindrical reinforcing member 40 shown in FIG. The rectangular tubular reinforcing member 50 shown in (b) may be a pentagonal or more polygonal tubular shape (not shown). These reinforcing members 3, 6, 40, and 50 are not provided with openings in the cylindrical wall, but a plurality of openings 11 that communicate the inside and the outside of the cylindrical body are provided as in the reinforcing member 10 shown in FIG. You may provide. When the opening 11 is provided in this way, the integrity of the foamed resin molded body on the inner side of the cylindrical body and the foamed resin molded body on the outer side is increased, and the EA characteristics of the EA material are improved.

  The opening is not limited to a circle, and may be an ellipse or a square.

  As the reinforcing member, a reinforcing member 20 made of a mesh may be used as shown in FIG. Even in the reinforcing member 20 made of this mesh, the integrity of the foamed resin molded body on the inner side of the cylindrical body and the foamed resin molded body on the outer side is good. Moreover, when the foamed resin molded body enters the mesh, the integrity between the reinforcing member 20 and the foamed resin molded body is also improved. In addition, the size (opening area) of the first mesh of the mesh may be about 3 mm × 3 mm to 20 mm × 20 mm.

  The reinforcing member may have a cylindrical bowl shape shown in FIG. The reinforcing member 30 includes a ring 31 arranged in multiple upper and lower stages and a rod-like vertical member 32 that connects the rings 31 to each other. The ring 31 is not limited to a circular shape, and may be any shape such as an ellipse or a square.

[Preferred examples of material of reinforcing member]
Examples of the constituent material of the non-porous reinforcing members 3, 6, 9, 40, 50 include paper, synthetic resin (for example, PP, PE, PS, ABS, PCB), cloth, and the like.

  In the case of a reinforcing member of a type in which an opening is provided in a cylindrical wall like the reinforcing member 10, the materials described above are exemplified.

  In the case of a reinforcing member made of a mesh like the reinforcing member 20, the material is exemplified by a synthetic resin (for example, the above).

  In the case of a bowl-shaped reinforcing member such as the reinforcing member 30, the ring and the vertical member are preferably made of the above synthetic resin or metal.

It is a perspective view of the EA material which concerns on embodiment. It is the II-II sectional view taken on the line of FIG. It is a perspective view of the EA material which concerns on another embodiment. It is a perspective view of the EA material which concerns on another embodiment. (A) A figure is a perspective view of a reinforcing member, (b) A figure is a BB line sectional view of (a) figure. (A) A figure is a perspective view of a reinforcing member, (b) A figure is a BB line sectional view of (a) figure. It is a perspective view of a reinforcing member. It is a perspective view of a reinforcing member. It is a perspective view of a reinforcing member. It is a perspective view of a reinforcing member. It is a stress-strain curve of EA material.

Explanation of symbols

1, 4, 7 EA material 2, 5, 8 EA material body 2a, 8a, 8b, 8c Front surface 2b, 8d Rear surface 3, 6, 9, 10, 20, 30, 40, 50 Reinforcing member

Claims (5)

In an EA material having an EA material body made of a foamed resin molded body having a front surface for receiving an object and a rear surface opposite to the front surface,
An EA material characterized in that a reinforcing member extending in a direction connecting the front surface and the rear surface is embedded in the EA material body.   The EA material according to claim 1, wherein the foamed resin molded body is made of a rigid polyurethane foam.   3. The EA material according to claim 1, wherein the reinforcing member is a cylindrical body and is embedded with a cylindrical axial direction as a front-rear direction.   4. The EA material according to claim 3, wherein an opening that communicates the inner side and the outer side of the cylinder is provided in a cylindrical wall portion of the cylindrical body.   The EA material according to claim 3, wherein the cylindrical body is made of a mesh.

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