WO2015163311A1

WO2015163311A1 - Shock absorbing member

Info

Publication number: WO2015163311A1
Application number: PCT/JP2015/062076
Authority: WO
Inventors: 浩二大石; 後藤　陽一; 英樹田内
Original assignee: スズキ株式会社
Priority date: 2014-04-23
Filing date: 2015-04-21
Publication date: 2015-10-29
Also published as: CN105358384A; DE112015000089T5

Abstract

　Provided is a shock absorbing member that makes it possible to efficiently transmit externally applied force and sufficiently absorb shock energy. Provided is a shock absorbing member that makes it possible to obtain, by vacuum molding or pressure molding, a resin thickness distribution suitable for shock absorption. This shock absorbing member is arranged between a body member of an automobile and internal/external claddings on the surface side of the body member, wherein the shock absorbing member is provided with a base part fixed to the body member side, a plurality of hollow conic protuberances protruding from the base part and having a top face, linear ribs protruding from the outer peripheral surfaces of the protuberances and extending from the top faces to the base part, and at least one small projection protruding from each of the top faces.

Description

Shock absorber

The present invention relates to an impact absorbing material used for protecting passengers and pedestrians in automobiles.

A variety of shock absorbers are interposed between the interior and exterior of the car to protect passengers or pedestrians. For example, shock absorbers for protecting the legs of pedestrians are inserted between automobile resin bumpers (bumper fascia) and body frames (bumper beams, etc.), and resin interior materials (instrument panels, door trims, roof linings) Etc.) and an impact absorbing material for protecting passengers is inserted between the vehicle body panel (see Patent Documents 1 to 3, etc.).

Patent Document 1 describes that a resin sheet molded article provided with a plurality of truncated conical protrusions having different heights is used as an impact absorbing material. The protrusion is hollow and has a linear rib on the outer peripheral surface, and can gradually absorb impact energy from the outside.

Further,

Patent Documents

2 and 3 disclose energy absorbers provided with adjacent frustoconical protrusions having the same height. The energy absorbers disclosed in

Patent Documents

2 and 3 are also molded by a thermoforming process starting from a thermoplastic sheet.

Japanese Patent No. 4448938 JP 2012-233583 A Special table 2008-524065 gazette

However, if the top surface of the truncated cone becomes slippery, the force input from the facing surface may not be efficiently transmitted to the truncated cone. In particular, as disclosed in

Patent Documents

2 and 3, in a place where the truncated cones made of the thermoplastic sheet are arranged side by side, a slip occurs between the top surfaces of the truncated cones and sufficiently absorbs the impact energy. May not be possible.

Therefore, an object of the present invention is to provide an impact absorbing material capable of efficiently transmitting an external force and sufficiently absorbing impact energy.

In order to achieve the above object, an impact absorbing material according to the present invention is an impact absorbing material disposed between a vehicle body member of an automobile and an interior / exterior material on the surface side thereof, and is fixed to the body member side. A plurality of hollow frustum-shaped protrusions protruding from the base part and having a top surface, linear ribs protruding from the outer peripheral surface of the protrusion and extending from the top surface to the base part, And at least one small protrusion protruding from the top surface.

Here, it is preferable that the at least one small protrusion is provided on an extension line of the rib on the top surface. Further, the small protrusion can be provided at substantially the center of the top surface of the protrusion. Further, a configuration in which a plurality of the small protrusions are provided around the approximate center of the top surface (a configuration in which the center positions of the plurality of small protrusions coincide with the approximate center of the top surface of the protrusion) may be employed.

Further, the protrusion has a hollow truncated pyramid shape, the top surface has a polygonal shape, and the at least one small protrusion is provided on a line connecting the vertex and the center of the polygonal shape. be able to. For example, the protrusion has a hollow hexagonal frustum shape, the top surface has a hexagonal shape, and the at least one small protrusion can be provided on a line connecting the vertex and the center of the hexagonal shape. .

Since the shock absorber of the present invention configured as described above has a small protrusion provided on the top surface of the hollow frustum-shaped protrusion protruding from the base portion, the surface is opposed to the top surface of the protrusion. The transmitted force is efficiently transmitted to the top surface where the frictional resistance is increased by the small protrusions, and the protrusions are individually crushed by the force and the impact energy can be sufficiently absorbed.

Also, if the small protrusion is provided at the approximate center of the top surface, a force can be input without bias to the protrusion, and it can be prevented from falling before being crushed. Furthermore, even when a plurality of small protrusions are provided on the top surface of the protrusion, the center position of the plurality of small protrusions is matched with the center of the top surface of the protrusion to prevent the protrusion from collapsing without collapsing. be able to.

Also, when the protrusion is formed on a truncated pyramid, the small protrusion can be arranged in accordance with the apex of the top surface of the polygon to distribute the force toward the highly rigid corner. Further, such small protrusions need not be provided for each vertex of the polygon, and may be provided as many as necessary.

Furthermore, in the aspect which has the small hole which can be utilized for gas discharge in the top surface of the said small protrusion, a small protrusion can be shape | molded reliably by utilizing the said small hole for venting.

It is a perspective view which shows the impact-absorbing material which concerns on 1st Embodiment of this invention. It is sectional drawing for demonstrating the structure of an impact-absorbing material. It is a perspective view which shows the projection part of the impact-absorbing material which concerns on 2nd Embodiment of this invention. It is a top view which shows the projection part of the impact-absorbing material which concerns on 3rd Embodiment of this invention. It is a top view which shows the projection part of the impact-absorbing material which concerns on 4th Embodiment of this invention. It is a perspective view which shows the impact-absorbing material which concerns on 5th Embodiment of this invention. FIG. 7 is a cross-sectional view taken along the line AA in FIG. It is sectional drawing which shows the formation process of the impact-absorbing material which concerns on 5th Embodiment of this invention.

Hereinafter, a shock absorber 1 for an automobile according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view for explaining the overall configuration of the shock absorber 1, and FIG. 2 is a cross-sectional view for explaining the detailed configuration around the protrusion 3.

1 is provided between a vehicle body member of an automobile and an interior material or exterior material on the surface side of the vehicle body member. For example, it corresponds to the inside of a car door, between the ceiling and the interior material, the bottom of the carpet, the inside of the window frame on the side surface of the vehicle body, the bumper and the vehicle body structural member inside the vehicle. Specifically, shock absorbers for protecting the legs of pedestrians are inserted between automobile resin bumpers (bumper fascia) and body frames (bumper beams, etc.), and resin interior materials (instrument panels, door trims) A shock absorber for protecting the occupant is inserted between the roof lining and the vehicle body panel.

As shown in FIG. 1, the shock absorber 1 protrudes from a base 2 fixed to the vehicle body, a plurality of protrusions 3,... Protruding from the base 2, and a top surface 31 of the protrusion 3. The small protrusion 5 (convex portion) and the rib 4 provided on the outer peripheral surface of the protrusion 3 are mainly provided.

The base part 2 is formed in a shape along the body part to be mounted. The base part 2, the protrusion part 3, the small protrusion part 5, and the rib 4 constituting the shock absorbing material 1 have an integrated structure, and a shell structure formed by vacuum forming a resin sheet mainly made of polypropylene (PP). None, the inside of the protrusion 3 is a hollow portion 20 penetrating downward. These wall thicknesses are formed to about 1 mm.
By using a resin sheet made of polypropylene as a main material, the shock absorber 1 can be easily molded and can be reduced in weight. In addition, since these materials are inexpensive, costs can be reduced and recyclability is also high.

In addition, the material of the resin sheet for molding the shock absorber 1 is not limited to the above-described polypropylene (PP). For example, acrylonitrile-butadiene-styrene (ABS) resin, acetate, polycarbonate, polystyrene, polyethylene (low density or high density), polyester, polyvinyl chloride (PVC) and the like can be used as a material.

Further, the molding method of the shock absorber 1 is not limited to the vacuum molding described above. For example, it can be molded by injection molding, press molding, stamping molding, extrusion molding, blow molding, slush molding, casting, foam molding, reaction injection molding (RIM) or powder molding.

On the other hand, the protrusion 3 is formed into a hollow truncated cone as shown in FIG. A plurality of protrusions 3,... Provided on the base portion 2 of the shock absorber 1 of the present embodiment has a truncated cone shape as shown in FIG. Here, the top surface 31 is a flat surface on the tip side parallel to the bottom surface of the truncated cone. Moreover, in this Embodiment, the height of several protrusion part 3, ... is made the same height altogether.

Further, the rib 4 is a portion protruding from the outer peripheral surface of the protruding portion 3 that linearly extends from the height of the top surface 31 of the protruding portion 3 toward the base portion 2. One or more ribs 4 are provided for one protrusion 3.

In the present embodiment, a case where the same number of ribs 4,... Are provided on the plurality of protrusions 3 as shown in FIG. Further, the rib 4 is not connected between the

adjacent protrusions

3 and 3 and is not provided on a line connecting the centers of the

adjacent protrusions

3 and 3.

The small protrusion 5 is provided at the approximate center of the top surface 31 of the protrusion 3. The small protrusions 5 are concave parts when viewed from the inside of the protrusions 3 as shown in FIG. The small protrusion 5 is formed in a cylindrical shape, for example.

The shock absorber 1 thus formed is attached between a vehicle body panel (vehicle body member) such as an automobile door or ceiling and an inner member. At this time, the base part 2 is fixed to the vehicle body panel or the inner member with a bolt or an adhesive, and the direction in which the protruding parts 3. Note that the shock absorber 1 may be fixed to the vehicle body by other methods.

When receiving the impact from the outside, the impact absorbing material 1 described above absorbs impact energy by the elastic deformation or plastic deformation, or the elastic deformation and plastic deformation of the protrusion 3 and the rib 4 due to the impact. When the protrusion 3 is plastically deformed, the protrusion 3 is buckled and crushed.

That is, a force acts on the protrusion 3 from the surface facing the inner member side to the top surface 31. A small protrusion 5 is provided at the center of the top surface 31 so as to protrude toward the inner member. For this reason, the frictional resistance (friction coefficient) with the facing surface is greater than when there is no small protrusion 5, and the transmitted force is also greater.

Further, since the small protrusion 5 is provided at the center of the top surface 31 of the protrusion 3, the force is easily transmitted to the center of the protrusion 3. For this reason, it becomes difficult to happen to fall down toward the adjacent projection 3 before the projection 3 is crushed due to the biased force.

Next, the operation of the shock absorber 1 of the present embodiment will be described.
In the shock absorber 1 of the present embodiment configured as described above, the rib 4 is provided on each protrusion 3. Here, if the adjacent projections 3 are not connected, the projections 3,. Moreover, if it is not connected in this way, the adjacent projection part 3 will not collapse, and another projection part 3 will not fall down, without absorbing energy.

Furthermore, by providing the rib 4 on the outer peripheral surface of the protrusion 3, the rigidity of the protrusion 3 is increased, and the amount of energy absorption can be increased. In addition, by setting the number and position of the ribs 4 provided on the outer peripheral surface of the protrusion 3, the impact energy absorption characteristics can be adjusted.

And such an impact-absorbing material 1 can gradually absorb energy when receiving an impact from the outside.

Moreover, since the energy absorption amount of the protrusion 3 can be increased by providing the rib 4 on the outer periphery of the protrusion 3 formed by the resin sheet, it is possible to reduce the weight of the shock absorber for automobiles.

The shock absorber 1 of the present embodiment thus configured has a small protrusion on the top surface 31 of the protrusion 3 formed in a truncated cone shape (conical frustum) protruding from the base portion 2. 5 is provided.

For this reason, the force transmitted from the surface facing the top surface 31 of the protrusion 3 is efficiently transmitted to the top surface 31 whose frictional resistance is increased by the small protrusion 5, so that the protrusion is caused by the force. The portions 3,... Can be individually crushed and the impact energy can be gradually absorbed.

Further, if the small protrusion 5 is provided at substantially the center of the top surface 31, a force can be input to the protrusion 3 without being biased, and it can be prevented from falling before being crushed.

Hereinafter, an impact absorbing material according to another embodiment of the present invention will be described with reference to FIGS. In addition, about the description of the part same or equivalent to the content demonstrated by the said embodiment, the same term or the same code | symbol is attached | subjected and demonstrated.

In the first embodiment, the projection 3 of the truncated cone has been described. However, in the shock absorber 1A of the second embodiment shown in FIG. 3, the projection 3A has a hexagonal frustum shape in which the top surface 31A is a regular hexagon. The cylindrical small protrusion 5A is provided at the center of the top surface 31A. The ribs 4,... Are provided corresponding to the positions of the apexes of the regular hexagon of the top surface 31A.

On the other hand, in the shock absorber 1B of the third embodiment shown in FIG. 4, a plurality of cylindrical small protrusions 5B,... Are provided on the top surface 31A of the protrusion 3A. The center positions of the plurality of small protrusions 5B,... Coincide with the center C of the top surface 31A of the protrusion 3A. Specifically, six small protrusions 5B,... Are respectively provided on a diagonal line D connecting the apex of the top surface 31A formed in a regular hexagon and the center C. If the distances between the small protrusions 5B,... And the center C of the top surface 31A are all equal, the center positions of the plurality of small protrusions 5B,... Coincide with the center C of the top surface 31A. become.

Further, in the shock absorber 1C of the fourth embodiment shown in FIG. 5, a plurality of small cylindrical protrusions 5C,... The plurality of small protrusions 5C,... Are not provided corresponding to all the vertices of the hexagonal top surface 31A, but on a line connecting every other vertex and the center C in the circumferential direction (diagonal line). D). The center positions of the three

small protrusions

5C, 5C, and 5C coincide with the center C of the top surface 31A.

As described above, even when the plurality of small protrusions 5B,... (5C,...) Are provided on the top surface 31A of the protrusion 3A, the plurality of small protrusions 5B,. By making the center position coincide with the center C of the top surface 31A of the projecting portion 3A, it is possible to input a force to the projecting portion 3A without deviation, and to prevent collapse without collapsing.

Further, when the protrusion 3A is formed in a truncated pyramid, the

small protrusions

5B and 5C are arranged so as to be aligned with the apex of the polygonal top surface 31A, thereby distributing the force toward the highly rigid corner. Can be made. In particular, by providing the rib 4, the rigidity of the corner can be further increased.

Further, the small protrusions 5C,... Need not be provided for each vertex of the polygon, and may be provided as many as necessary, for example, every other vertex of the polygon.
Other configurations and functions and effects are substantially the same as those in the above-described embodiment, and thus description thereof is omitted.

6 to 8 show an impact absorbing material 1D according to the fifth embodiment of the present invention.
The shock absorber 1D has a shell structure formed by pressure forming (or vacuum forming) a resin sheet (2) having a uniform thickness, and includes a flat base portion 2 and a large number of protrusions 3D. The inside of 3 is a hollow portion 20 penetrating downward.

Each protrusion 3D has basically the same shape, and each cross section has a rounded star polygonal shape (hexagonal star shape) and has six ribs 4 (ridges). The number of ribs 4 (ridges) is not limited to 6, and may be 7 or more or 5 or less. In the illustrated example, the protrusions 3D are arranged in a square lattice shape, but may be arranged in a hexagonal lattice shape, an oblique lattice shape, or at random.

A small protrusion 5D protrudes from the flat top surface 31 of each protrusion 3. In the illustrated example, only one small protrusion 5D protrudes from the approximate center of the top surface 31. However, as described above, a plurality of small protrusions 5D may be provided. The small protrusion 5D is provided corresponding to an exhaust hole 16 of a molding die described later, and a small hole penetrating the small protrusion 5D is formed.

When manufacturing the impact absorbing material 1D, a molding die 11 as shown in a cross-sectional view in FIG. 8 is used, and pressure forming is performed in a direction opposite to that of general vacuum forming. The molding die 11 is a concave mold in which a flat mold 12 for molding the base portion 2 is provided with a concave mold portion 13 for molding the protruding portion 3D, and an exhaust hole 16 is formed in the bottom surface 14 of the concave mold portion 13. A small concave portion corresponding to the small protrusion 5D is provided at substantially the center of the bottom surface 14 where the exhaust hole 16 is opened. In other words, the upper end portion of the exhaust hole 16 is expanded in diameter.

The resin sheet (2) is transferred onto the mold 11 in a heated and softened state before molding, and then the upper side of the mold 11 is closed by a compressed air box (not shown), and compressed air is put into the compressed air box. By being blown and pressurized (+ P), the softened resin sheet is pressed against the mold 11, and the resin sheet swells into the recessed mold part 13, thereby forming a hollow protrusion 3 </ b> D.

At this time, since the cooling starts when the resin sheet is pressed against the molding die 11, the resin sheet is stretched toward the tip of the protrusion 3D, and the thickness (d) of the resin is reduced accordingly. Finally, the thinnest end of the resin sheet is pressed against the bottom surface 14, and the compressed air is exhausted through the exhaust holes 16, whereby the resin is pressed into the small recesses and the small protrusions 6 are formed. By forming a small hole in advance in the resin sheet corresponding to the small protrusion 5D and using the small hole for air venting, the small hole is reliably guided to the small recess (exhaust hole 16). There is an advantage that the moldability of 5D is improved and the thickness distribution of the protrusion 3D is improved. Molding is completed by releasing the mold after cooling.

As shown in FIG. 7, the shock absorbing material 1D formed as described above is interposed between the mounting surface 41 on the vehicle body side and the interior material (or exterior material) 42, and the base portion 2 is disposed on the vehicle body side. The mounting surface 41 is fixed. In this state, the height of the protrusion 3 </ b> D is adjusted in advance so that the small protrusion 5 </ b> D on the top surface 31 of the protrusion 3 </ b> D contacts the back surface of the interior material 42. As described above, the impact absorbing material 1D has a characteristic that the thickness d of the resin is smaller as the height h from the base portion 2 is higher, and the tip side of the protruding portion 3D is more easily deformed.

When an occupant collides with the interior material 42 of the automobile interposing the impact absorbing material 1D due to an unexpected situation, when the impact force F is applied to the interior material 42, the impact absorbing material 1D is positioned on the tip side of the protrusion 3D ( 4 and 6), an initial deformation is induced, and an ideal energy absorption pattern in which the amount of absorption increases as the deformation progresses from the distal end to the proximal end side.

In the above embodiment, the case where the shock absorbing material 1D is pressure-formed is described. However, the cavity (not shown) on the lower side of the exhaust hole 16 is decompressed with a vacuum pump and sucked through the exhaust hole 16, The shock absorber 1D can also be vacuum formed.

The embodiment of the present invention has been described in detail above with reference to the drawings. However, the specific configuration is not limited to this embodiment or example, and the design changes are within the scope of the present invention. Are included in the present invention.
For example, in the above-described embodiment, when the shock absorber 1 is installed in an automobile, the direction in which the protruding portion 3 protrudes from the base portion 2 is the vehicle interior side. The absorbent material 1 may be installed in a different direction.

In the above embodiment, the case where the protrusions 3,... Have the same height has been described. However, the present invention is not limited to this, and protrusions having different heights may be adjacent to each other. In such a configuration, when the impact is applied, the high-height protrusion first deforms, and then the low-height protrusion deforms. Characteristics can be adjusted.

Furthermore, in the above-described embodiments and examples, the cylindrical

small protrusions

5, 5A to 5D have been described. However, the present invention is not limited to this, and may be a dome-shaped or conical small protrusion. .

Moreover, in the said embodiment, although the number of ribs 4 ... provided in several protrusion part 3, ... was made the same, it is not limited to this, The number of ribs for every protrusion part Can be set arbitrarily.

1, 1A to 1D Shock absorber 2

Base portion

3, 3A,

3D Projection portion

31, 31A Top surface 4

Ribs

5, 5A to 5D Small protrusion portion 11 Mold 12 Flat portion 13 Recessed portion 16 Exhaust hole C Center D Diagonal line d thickness

Claims

A shock absorber disposed between a body member of an automobile and an interior / exterior material on the surface side thereof,
A base portion fixed to the vehicle body member side;
A plurality of hollow frustum-shaped protrusions protruding from the base and having a top surface;
A linear rib protruding from the outer peripheral surface of the protrusion and extending from the top surface to the base portion;
At least one small protrusion protruding from the top surface;
A shock absorbing material characterized by comprising:
The impact absorbing material according to claim 1, wherein the at least one small protrusion is provided on an extension line of the rib on the top surface.
3. The impact absorbing material according to claim 2, wherein the at least one small protrusion is provided substantially at the center of the top surface.
4. The impact absorbing material according to claim 2, wherein a plurality of the at least one small protrusion is provided around a substantial center of the top surface.
The protrusion has a hollow truncated pyramid shape, the top surface has a polygonal shape, and the at least one small protrusion is provided on a line connecting the vertex and the center of the polygonal shape. The shock absorber according to claim 4.
The protrusion has a hollow hexagonal frustum shape, the top surface has a hexagonal shape, and the at least one small protrusion is provided on a line connecting the vertex and the center of the hexagonal shape. The impact absorbing material according to claim 5, wherein
The shock absorber according to claim 6 or 7, wherein the shock absorber has a small hole that can be used for gas discharge on a top surface of the small protrusion.