JP2000085504A - Impact energy absorbing structure and impact energy absorbing material of automobile body upper part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an impact energy absorbing structure of an upper part of an automobile body, which can be put into effect when a displacement distance for an energy absorbing material is different. SOLUTION: This is a structure absorbing impact energy of an upper part of an automobile body having a structure member, a trimming material disposed at intervals inside the structure member, and an energy absorbing material disposed within the intervals. The energy absorbing material is a hybrid pipe 70 consisting of metal leaf of a core material 72 and nonmetal sheets 74 laid on front and back sides of the core material, respectively. The hybrid pipe is formed to make the core material and the sheets 74 on the front and back sides deformed for having recessed parts 76 and protruding parts 78 in an axial direction consecutively, and is formed to make two pitches (P1, P2) between two protruding parts disposed next to each other partly different in an axial direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an impact energy absorbing structure and an impact energy absorbing material on an upper part of a vehicle body of an automobile.
In particular, structural members of the vehicle body such as pillars, roof side rails, and headers, and interior materials such as pillar garnishes and roof linings that are arranged at intervals in the cabin of the structural members, and are arranged within the intervals. The present invention relates to a structure for absorbing impact energy in an upper part of a vehicle body provided with an impact energy absorbing material and a shock energy absorbing material suitable for the absorbing structure.

[0002]

2. Description of the Related Art An energy absorbing material is disposed in a space between a structural member of a vehicle body, particularly a passenger car body, and an interior material. When an impact load is applied from the interior material to the structural member, the energy absorbing material is removed. It is deformed to absorb the impact energy of the impact load. Usually, a lattice-shaped rib or urethane pad, a thin steel plate which is bent so as to have a hat-shaped cross section, or the like is used as the energy absorbing material.
It consists of a core material of metal foil and a sheet of material other than metal superposed on the front and back surfaces of the core material, and the core material and the front and back sheets are formed by continuously deforming in the axial direction into irregularities. In some cases, a so-called hybrid pipe is used (Japanese Patent Laid-Open No. 10-29482).

[0003]

Depending on the location of the cabin to which an impact load is applied, the size of the interval at which the energy absorbing material should be arranged, that is, the displacement distance allowed for the displacement of the energy absorbing material is small, There are times when you can afford. In such a case, in the former, it is necessary to use an energy absorbing material in which the load rises steeply, whereas in the latter, an energy absorbing material in which the load rises relatively slowly can be used.

In the case where an energy absorbing material is disposed between a structural member of a vehicle body and an interior material, an attachment portion of the interior material to the structural member or its vicinity, or an attachment portion of the assist grip to the structural member or its vicinity. It is preferred that the energy absorbing material has a lower load-to-displacement energy absorbing property than the other parts in certain parts such as

As described above, the conditions required for the energy absorbing material differ depending on the part of the vehicle body where the energy absorbing material is to be arranged. The hybrid pipe described in the publication has a constant cross-sectional shape over its entire length, and a radial plate thickness from the outermost surface of the convex portion to the innermost surface of the concave portion, that is, an apparent plate thickness is constant. . Therefore, in order to satisfy the requirements of each part of the vehicle body, a plurality of hybrid pipes having one or more of different cross-sectional shapes, dimensions, and apparent plate thicknesses are prepared, and each of the hybrid pipes is cut to an appropriate length and each of the hybrid pipes is cut to an appropriate length. It is necessary to dispose them at different parts, and the production and installation work of a plurality of hybrid pipes becomes complicated.

The present invention provides an impact energy absorbing structure for an upper part of a vehicle body, which has an energy absorbing material capable of responding to the requirements of a part to be absorbed.

[0007] The present invention also provides an impact energy absorbing material that can meet the requirements of the site where energy is to be absorbed.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a structural member of a vehicle body, an interior member disposed inside the structural member at an interval, and an energy absorbing member disposed within the interval. And a structure for absorbing impact energy in an upper portion of a vehicle body having a material. The energy absorbing material is a hybrid pipe comprising a core material of a metal foil and sheets of a material other than metal, which are respectively superposed on the front and back of the core material.

In one aspect of the present invention, the hybrid pipe is formed by continuously deforming the core material and the front and back sheets into an uneven shape in the axial direction, and the two convexes positioned adjacent to each other in the axial direction. The pitch between the portions or the concave portions is formed so as to be partially different in the axial direction.

When the hybrid pipe is compressed in a direction crossing the axis, it expands in the axial direction and has a property of reducing the apparent plate thickness. The axial elongation at the same load increases as the pitch increases, and the amount of decrease in the apparent plate thickness increases.Therefore, if the apparent thickness is the same, the apparent pitch is larger at a larger pitch than at a smaller pitch. The amount of reduction in plate thickness increases.

Since there is a portion having a different pitch in the axial direction of the hybrid pipe, if the pitch of that portion is larger than the pitch of the other portion, the rise of the load at that portion becomes slower than at other portions, and conversely. If the pitch of the portion is smaller than the pitch of the other portion, the rise of the load at the portion becomes steeper than that of the other portion. This makes it possible to arrange the hybrid pipe in accordance with the part where energy is to be absorbed, and to achieve appropriate energy absorption.

[0012] An energy absorbing structure using a locally optimized hybrid pipe can be obtained without using a plurality of hybrid pipes having different cross-sectional shapes and cross-sectional dimensions. Further, since the hybrid pipe can be easily bent and is lightweight, it can be easily arranged along the structural member or the interior material.

According to another aspect of the invention, the hybrid pipe has an uneven portion having a predetermined pitch and a large pitch uneven portion having a pitch larger than the pitch of the uneven portion. In this case, the large pitch uneven portion is arranged at the intermediate portion of the hybrid pipe.

An energy absorbing material is used in such a manner that the large pitch uneven portion is located at, for example, a mounting portion of the interior material. Then, the concave and convex portions having the predetermined pitch are located at portions other than the mounting portion. As a result, the rise of the load at the mounting portion becomes gentler than the rise of the load at a portion other than the mounting portion.

When a load is applied in a direction intersecting with the axis of the hybrid pipe, the irregularities at a predetermined pitch and the large pitch irregularities compress and deform to absorb energy, but when a load is applied in the axial direction of the hybrid pipe, The hybrid pipe bends at large pitch irregularities, and exhibits an extremely low load-to-displacement energy absorption characteristic with respect to load. This is because the amount of energy absorption differs depending on the direction of the load, and so-called directivity can be provided.

In another aspect of the present invention, the hybrid pipe has an uneven portion having a predetermined pitch and a plurality of large pitch uneven portions having a pitch larger than the pitch of the uneven portion. In this case, the plurality of large pitch uneven portions are arranged at predetermined intervals in the axial direction of the hybrid pipe.

[0017] The unevenness of the hybrid pipe at a predetermined pitch is less elongated in the axial direction than the large pitch unevenness. For this reason, when an impact load is applied to the large pitch unevenness from the direction intersecting the axis, the large pitch unevenness is compressed and deformed and extends in the axial direction. However, this expansion is suppressed by the predetermined pitch unevenness. As a result, the overall deformation of the hybrid pipe is suppressed. As a result, even if an impact load is again applied to another part after the impact load is applied, energy can be sufficiently absorbed while maintaining the initial performance.

Still another aspect of the present invention relates to an impact energy absorbing material made of a hybrid pipe composed of a metal foil core material and sheets of a material other than metal, which are superposed on the front and back surfaces of the core material, respectively. The hybrid pipe is formed by continuously deforming the core material and the front and back sheets into an uneven shape in the axial direction, and a pitch between two convex portions or concave portions located adjacent to each other in the axial direction. It is formed so as to be partially different in the axial direction.

The impact energy absorbing material made of the hybrid pipe is disposed between the structural member and the interior material, for example, in the upper part of the vehicle body having the structural member and the interior material, so that the impact energy absorbing material is suitable for a portion where energy is to be absorbed. An impact energy absorbing structure having improved energy absorbing characteristics can be obtained.

[0020] In still another invention, the hybrid pipe is formed by continuously deforming the core material and the front and back sheets into an uneven shape in the axial direction, and has an apparent plate thickness that is partially changed in the axial direction. Are formed so as to be different from each other.

As described above, when the hybrid pipe is compressed from a direction intersecting the axis, it expands in the axial direction,
It has the property of reducing the apparent plate thickness. If the pitch is the same, the rate of decrease in the apparent plate thickness is greater in a portion where the apparent plate thickness is small than in a portion where the apparent plate thickness is large.

Since there are portions where the apparent plate thickness differs in the axial direction of the hybrid pipe, if the apparent plate thickness of that portion is larger than the apparent plate thickness of the other portions, the rise of the load at that portion may be different. If the apparent plate thickness of that portion is smaller than the apparent plate thickness of the other portion, the rise of the load at that portion becomes gentler than at other portions. This makes it possible to arrange the hybrid pipe in accordance with the part where energy is to be absorbed, and to achieve appropriate energy absorption.

An energy absorbing structure using a locally optimized hybrid pipe can be obtained without using a plurality of hybrid pipes having different cross-sectional shapes and cross-sectional dimensions. Further, since the hybrid pipe can be easily bent and is lightweight, it can be easily arranged along the structural member or the interior material.

In still another aspect of the present invention, the hybrid pipe has an uneven portion having a predetermined apparent thickness and a reduced thickness portion having an apparent thickness smaller than the apparent thickness of the uneven portion.

When an impact load is applied from a direction intersecting the axis of the hybrid pipe, the rise of the load in the portion where the thickness is reduced becomes gentler than in other portions. Therefore, the energy absorbing material is arranged and used so that the reduced thickness portion comes to, for example, the mounting portion of the interior material.

Since the thickness reduction portion is provided in the hybrid pipe, a partially low load-displacement energy absorption characteristic can be obtained. Therefore, it is not necessary to prepare and attach a plurality of hybrid pipes having different cross-sectional shapes even in a place where the hybrid pipe should be installed, particularly in a place where it is preferable to have a low load-displacement energy absorption characteristic. Can be dealt with by the hybrid pipe, and the production and installation work is simple.

[0027] In still another aspect of the present invention, the thickness-reduced portion includes:
This is a cross-sectional reduction portion in which the cross section is reduced by compressing the hybrid pipe formed in a constant cross section from the outer peripheral side.

When a load is applied from a direction intersecting the axis, the hybrid pipe has the property of extending in the axis direction.
For this reason, in the cross-section reduced portion in which the cross-section is reduced by the compression deformation, elongation deformation occurs in the axial direction, and the apparent plate thickness is reduced. The load-displacement energy absorption characteristic becomes steeper as the apparent plate thickness is larger. Therefore, a lower load-displacement energy absorption characteristic is obtained by reducing the apparent plate thickness.

Since a hybrid pipe having a predetermined energy absorption characteristic can be manufactured only by partially reducing the cross section by compressing and molding a hybrid pipe having a predetermined cross-sectional shape in advance, the manufacture thereof is easy. Also, by changing the rate of compression to reduce the cross section, the energy absorption characteristics of load versus displacement can be adjusted. Also,
When the hybrid pipe has a square cross section, by compressing and deforming the two opposing surfaces to reduce the cross section,
A hybrid pipe with directivity can be obtained.

[0030] In still another invention, the plate thickness reduction portion is
This is a cross-sectional enlarged portion in which the cross section is enlarged by partially expanding the hybrid pipe formed in a constant cross section from the inner peripheral side.

As described above, the hybrid pipe has the property of expanding in the axial direction when a load is applied from the direction intersecting the axis. Deformation has occurred, reducing the apparent plate thickness. As a result, the same operation and effect as when the cross section is reduced can be obtained.

In still another aspect of the present invention, the hybrid pipe has an uneven portion having a predetermined radial dimension intersecting the axial direction, and a small-dimension uneven portion having a radial dimension smaller than the radial dimension of the uneven section. And the small-sized uneven portion serves as the plate thickness reduced portion. When forming the hybrid pipe, the uneven part and the small-sized uneven part are obtained, but since the small-sized uneven part is the reduced thickness part, by selecting the apparent thickness of the reduced thickness part It is possible to adjust not only the load-displacement energy absorption characteristics of the reduced thickness portion compared to the other portions of the hybrid pipe, but also the load-displacement energy absorption characteristics of the small-sized uneven portion itself. Can be greatly expanded.

In still another aspect of the present invention, the hybrid pipe includes an uneven portion having a predetermined apparent plate thickness formed by continuously deforming the core material and the front and back sheets in the axial direction into an uneven shape. A flat plate-thickness reduced portion having no plate deformation and having a plate thickness smaller than the apparent plate thickness of the uneven portion.

The flat plate thickness reduced portion is compressed and deformed when an impact load in a direction intersecting with the axis is applied, but does not substantially expand in the axial direction. In addition, since it has a flat shape with no irregularities, it is possible to obtain a hybrid pipe having the smallest thickness compared to the apparent thickness of the irregularities and having a partially lowest load-displacement energy absorption characteristic.

[0035] In still another invention, the thickness-reduced portion is:
When a shock load is applied via the interior material, the member is disposed at or near a structural member of the vehicle body that generates a large reaction force load.

In the vicinity of, for example, a mounting portion of an interior material such as a pillar garnish or roof lining or a mounting portion of an assist grip, or a vicinity thereof, a seat for mounting is provided or a connection such as a clip or a bolt is provided. Due to the insertion of the means, the rigidity is higher than other parts of the interior material. When an impact load is applied to the hybrid pipe via the interior material, a reaction force load is generated due to the deformation of the interior material and the hybrid pipe,
In the mounting portion and its vicinity, a large reaction force load is generated due to the increased rigidity. According to the present invention, since the reduced thickness portion of the hybrid pipe is disposed at a position where a large reaction load is generated, a substantially uniform reaction load can be generated over the entire length of the hybrid pipe, and the substantially uniform reaction load can be generated. Can be obtained.

According to still another aspect of the present invention, the thickness reduced portion is
It is provided at an intermediate portion in the axial direction of the hybrid pipe.

By properly selecting the length of the reduced thickness portion in the axial direction, a predetermined load-to-displacement energy absorption characteristic can be exhibited with respect to an impact load applied from a direction intersecting the axis. When a load in the axial direction is applied to the hybrid pipe, the hybrid pipe breaks at the reduced thickness portion in the intermediate portion, and therefore does not substantially perform the energy absorbing function with respect to the load in the axial direction. In this way, the directivity can be given to the hybrid pipe.

In still another aspect of the present invention, a plurality of the thickness reducing portions are provided, and are arranged at predetermined intervals in the axial direction of the hybrid pipe.

In the portion where the thickness of the hybrid pipe is reduced, the elongation in the axial direction is small, or substantially no elongation occurs. Therefore, when an impact load is applied to a portion other than the plate thickness reduced portion of the hybrid pipe from a direction intersecting the axis, the portion is compressed and deformed and extends in the axial direction, but this expansion is suppressed by the plate thickness reduced portion. As a result, the overall deformation of the hybrid pipe is suppressed. As a result, even if an impact load is again applied to another part after the impact load is applied, energy can be sufficiently absorbed while maintaining the initial performance.

Still another aspect of the present invention relates to an impact energy absorbing material made of a hybrid pipe composed of a core material of a metal foil and sheets of a material other than metal superposed on the front and back surfaces of the core material. The hybrid pipe is formed by continuously deforming the core material and the front and back sheets into irregularities in the axial direction, and is formed such that an apparent plate thickness is partially different in the axial direction. .

The impact energy absorbing material made of the hybrid pipe is disposed between the structural member and the interior material, for example, in the upper part of the vehicle body having the structural member and the interior material, so that the impact energy absorbing material is suitable for a portion where energy is to be absorbed. An impact energy absorbing structure having improved energy absorbing characteristics can be obtained.

[0043]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 28, which is a sectional view of a structure for absorbing an impact energy, a structural member 40 of a vehicle body and an interior material (pillar garnish) 42 arranged inside the structural member 40 with a space therebetween. And an energy absorbing member 44 disposed in the above-mentioned space to absorb impact energy in the upper part of the vehicle body. In the embodiment of FIG. 28, the structural member 40 is a front pillar having an inner panel 46, an outer panel 48, and a reinforcing panel 50, and a flange of each panel is overlapped and joined to form a closed cross-sectional structure.

FIG. 2 is a sectional view of the impact energy absorbing structure.
Referring to FIG. 9, the structural member 52 of the vehicle body and the structural member 52
The impact energy is absorbed in the upper part of the vehicle body having an interior material (roof lining) 54 arranged at an interval inside and an energy absorbing material 56 arranged at the interval. In the embodiment shown in FIG. 29, the structural member 52 is a roof side rail having an inner panel 58 and an outer panel 60, and a flange of each panel is overlapped and joined to form a closed structure.

As shown in FIG. 30, the impact energy absorbing structure includes a center pillar 61, a quarter pillar 63, a front header 65 or a rear header 67.
In this case, the energy absorbing material can be disposed within the space between the structural member and the interior material disposed inside the structural member.
That is, the energy absorbers 62, 64, 66, and 68 corresponding to the center pillar 61, the quarter pillar 63, the front header 65, and the rear header 67 can be provided. In this case, the energy absorbing material can have an appropriate shape and size depending on a portion where the energy absorbing material is disposed, such as the energy absorbing material 44 in FIG. 28 or the energy absorbing material 56 in FIG. In the following, the invention will be described for a typical energy absorbing material, irrespective of the shape and dimensions of the energy absorbing material.

The energy absorbing member 70 shown in FIG. 1 in a cross-sectional state and FIG. 2 in a perspective state includes a core 72 made of a metal foil and a sheet of a material other than metal superposed on the front and back of the core 72. 74 is a hybrid pipe.
The metal foil core 72 and the sheet 74 are fixed with an adhesive. The hybrid pipe 70 is formed by continuously connecting the core material 72 and the front and back sheets 74 in the axial direction with the concave portions 76 and the convex portions 78.
And is formed to have Further, the hybrid pipe 70 is formed such that pitches P ₁ and P ₂ between two convex portions or concave portions located adjacent to each other in the axial direction are partially different in the axial direction.

In the embodiment shown, the core 72 is a hard aluminum foil and the sheet 74 is kraft paper. Aluminum foil has a thickness of at least 0.05 mm and a width of at least 30 mm, and kraft paper has a thickness of at least 0.2 mm and a width of at least 30 mm. The core 72 may be a stainless steel foil or a magnesium alloy foil, and the sheet 74 may be a resin. In FIG. 2, the irregular deformation is spiral.
Alternatively, a so-called wavy shape (bellows shape) may be used in which one concave portion 76 is continuous in the circumferential direction, and two independent convex portions 78 adjacent to the one concave portion 76 are continuous in the circumferential direction.

The hybrid pipe 70 shown in FIGS. 1 and 2 has an uneven portion 80 having a predetermined pitch P ₁ and an uneven portion 8.
Large pitch irregularities 8 with a pitch P ₂ larger than a pitch P _{1 of} 0
1, and the large pitch uneven portion 81 is arranged in the middle of the hybrid pipe 70. Hybrid pipe 7
0 may also be the opposite pitch, i.e. the pitch P ₂ of the uneven portion disposed in the intermediate portion is formed to be smaller than the pitch P ₁ of the other portion. Hybrid pipe 70
The radial distance from the outermost peripheral surface of the convex portion 78 to the innermost peripheral surface of the concave portion 76, that is, the apparent plate thickness t is the same for the uneven portion 80 and the large pitch uneven portion 81.

[0049] The hybrid pipe can be further formed such that the pitch at the end thereof is different from the pitch at other portions. The hybrid pipe 90 shown in FIG. 3 in a perspective state has an uneven portion 92 having a predetermined pitch and a plurality of large pitch uneven portions 93 having a pitch larger than the pitch of the uneven portion 92. The large pitch uneven portion 93 is a hybrid pipe. 90 are arranged at predetermined intervals in the axial direction.

The hybrid pipes 70, 90
2 and the front and back sheets 74 are wound around a spindle to form a cylindrical body, and the cylindrical body is passed between mold rollers to form irregularities at a predetermined pitch. Product. Therefore, when the cylindrical body is passed between the mold rollers, the pitch can be partially changed by using mold rollers having different pitches. Further, since the hybrid pipe has high ductility in the axial direction, a product made as a product having a constant pitch can be partially stretched in the axial direction and plastically deformed, whereby the pitch can be partially changed.

Referring to FIG. 1 again, the impact energy absorbing material according to the present invention comprises a core 72 made of metal foil and a sheet 7 made of a material other than metal, which is superposed on the front and back of the core 72.
It is made by a hybrid pipe 70 which is equivalent to four.
The hybrid pipe 70 includes a core member 72 and front and back sheets 7.
4 is formed by continuously deforming in the axial direction into an uneven shape,
Further, two convex portions 78 located adjacent to each other in the axial direction
The pitch between the concave portions or the concave portions 76 is formed so as to be partially different in the axial direction. As described above, the pitch is partially varied.

When the experiment was repeated while changing the pitch P, as shown in FIG. 4 showing the energy absorption characteristics of the load F versus the displacement S, the pitch of the hybrid pipes 94, 96, 98, 100 was 94 <96 <98 <100. , The rising of the load F is 94>96>98> 100.
, And the displacement S becomes larger in the order of 94 <96 <98 <100. Therefore, partially changing the pitch in the axial direction of the hybrid pipes 70 and 90 results in changing the energy absorption characteristics of each portion in the axial direction.

The hybrid pipe 70 can be arranged, for example, at the intersection of the roof side rail and the front pillar. At this intersection, since the interval between the interior material is narrow, it is preferable to dispose the hybrid pipe 70 having a sharp rise in load and having a small energy absorption characteristic with small displacement. Use a hybrid pipe with a smaller pitch than the other parts.

The rise of the load F and the magnitude of the displacement S can be changed by changing the pitch P of the hybrid pipe for the following reason. Referring to FIG. 5 in a cross-sectional state, the apparent thickness t of the hybrid pipe before deformation is a predetermined value for each product when the product is completed. Now, when an impact load is applied in a direction intersecting with the axial direction A, that is, in a direction B perpendicular to the drawing, the hybrid pipe has a large ductility in the axial direction, so that the hybrid pipe is extended in the axial direction. State.
In this state, the apparent thickness t 'is smaller than the apparent thickness t before the product is completed, that is, before deformation. That is,
Although the actual pipe thickness d of the hybrid pipe is the same, as a result of the hybrid pipe extending in the axial direction, the apparent thickness t ′ becomes thinner, and at the same time, the pitch P before deformation becomes smaller than the apparent pitch P ′. It is so big. In general, the strength of the pipe is not limited to the hybrid pipe, but increases as the thickness of the pipe increases. In the case of the hybrid pipe, the apparent thickness affects the strength. And
As the pitch P before deformation is larger, the apparent pitch P 'is larger, and as the apparent pitch P' is larger, the apparent plate thickness t 'is smaller and the rise of the load is slower.
The area of the energy absorption characteristic diagram given by the load and the displacement is the work, that is, the energy absorption amount. Therefore, the displacement increases as the load rises slowly.

As shown schematically in FIG. 6, a square metal extruded tube having a plate thickness of t and a side length of L, an apparent plate thickness of t when the product is completed, ie, before deformation, and a side length of t When an experiment was conducted on a hybrid pipe having a square shape of L, the apparent thickness of the hybrid pipe 102 gradually decreased from t due to the load F in the direction perpendicular to the axis, and the apparent thickness in the completely compressed state 104a was reduced. Sheet thickness t
Since the actual plate thickness d becomes thinner, the remaining uncrushed portion of the hybrid pipe is 2d ((b) in the figure). On the other hand, in the extruded tube 104, the plate thickness t does not change due to the load F, and the uncrushed portion is 2t in the completely compressed state 104a ((c) in the same figure).

FIG. 7 showing energy absorption characteristics of load versus displacement.
In the hybrid pipe 102, the load rises linearly until the maximum load F ₀ is reached, and after reaching the maximum load, the load decreases as the displacement increases, and the maximum displacement (L
-2d) ((a) in the figure). In contrast, the load until the maximum load F ₀ in extruded tube 104 rises linearly, after reaching the maximum load hardly changed the load be displaced is increased, the maximum displacement (L-2
t) ((b) in the figure). As is evident from FIG. 7, after reaching the maximum load in the hybrid pipe 102, the load decreases with the displacement.
In No. 4, the load is almost constant. Further, the maximum displacement of the hybrid pipe 102 is larger than the maximum displacement of the extruded pipe 104. Therefore, in the hybrid pipe 102, the average load can be reduced.

The hybrid pipe 70 is shown in FIGS.
Is formed so that the pitch of the intermediate portion 81 is smaller than the pitch of the other portions 80, and this hybrid pipe is formed by the intermediate portion 8 having a small pitch.
1 is arranged on the vehicle body such that, for example, it comes to the intersection of the front pillar and the roof side rail.

An impact load is applied from the direction intersecting the axis of the hybrid pipe 70 through the interior material, and
When compressing 1, the middle part 81 extends in the axial direction,
The apparent thickness decreases. At this time, since the pitch of the intermediate portion 81 is smaller than the pitch of the other portions 80, the degree of reduction in apparent plate thickness is smaller than that of the other portions 80, and an energy absorption characteristic with a sharp rise in load can be obtained. . As a result, sufficient energy absorption can be achieved at the intersection between the front pillar and the roof side rail, where the distance between the interior pillar and the front pillar is small. On the other hand, in the other portion 80 of the hybrid pipe 70, the pitch is larger than the pitch of the middle portion 81, so that when an impact load is applied thereto, the degree of reduction in the apparent plate thickness becomes large, and the rise of the load is slow. Although it has an absorption characteristic, the other portion 80 can secure a larger displacement amount than the intermediate portion 81, so that sufficient energy absorption can be achieved.

By providing a plurality of pitch portions having different axial elongations, an arrangement having different hardnesses in the axial direction becomes possible, and the hybrid pipe 70 can have required energy absorption characteristics.

The hybrid pipe 110 shown in FIG. 8 in a sectional state is composed of a metal foil core material 72 and a sheet 74 of a material other than metal adhered to the core material 72 and superposed on the front and back of the core material 72, respectively. Become. Hybrid pipe 11
No. 0 is formed by deforming the core material 72 and the front and back sheets 74 so as to have the concave portion 76 and the convex portion 78 continuously in the axial direction, and is the same as the hybrid pipe 70 in this point. The hybrid pipe 110 is formed such that an apparent plate thickness, which is a radial distance from the outermost peripheral surface 112 of the convex portion 78 to the innermost peripheral surface 114 of the concave portion, is partially different in the axial direction.

In the embodiment shown in FIG. 8, the hybrid pipe 110 is provided with an uneven portion 116 having a predetermined apparent plate thickness t ₂ ,
An apparent plate thickness t ₁ smaller than the apparent plate thickness of the uneven portion.
And a plate thickness reduction portion 117. The plate thickness can be partially varied in the axial direction of the hybrid pipe 110 by changing the mold roller described above.
In this case, the pitch between the portion having a large apparent plate thickness and the portion having a small apparent plate thickness is constant in the axial direction.

The apparent plate thickness at the time of product completion, that is, the apparent plate thickness t ₂ before deformation is larger than the apparent plate thickness t ₁ means that the strength against the impact load in the direction intersecting the axis is large. Therefore, in the concave-convex portion 116 of the hybrid pipe 110, it is possible to obtain an energy absorption characteristic in which the load rises more steeply than the plate thickness reduced portion 117. That is, referring to FIG. 9, which shows the energy absorption characteristics of load versus displacement, the hybrid pipes 118, 120, 122, 1
At 24, when the plate thickness increases in the order of 124 <122 <120 <118, the rise of the load increases to 124 <122.
<120 <118, and the displacement becomes 118 <12.
The values increase in the order of 0 <122 <124.

Also in the case of the hybrid pipe 110, the same operation and effect as the hybrid pipe 70 can be obtained by arranging the hybrid pipe 110 such that the thick part is located at the intersection.

The hybrid pipe 130 shown in FIG. 10 in a perspective state has a reduced thickness portion 132 at an intermediate portion where the apparent thickness is partially small, but the reduced thickness portion 132 is a hybrid pipe 130 having a constant cross section. Is a cross-sectional reduced portion obtained by compressing and deforming from the outer peripheral side to reduce the cross-section. That is, the portion 134 of the hybrid pipe 130 excluding the intermediate portion 132 is an uneven portion with the hybrid pipe formed and maintained at a constant cross section, and the intermediate portion is partially compressed and deformed to form a cross section reduced portion 132. The cross-section reduction section 132
It can be made by press forming or hammering from the outer peripheral side of the hybrid pipe and compressively deforming it. In the embodiment shown in FIG. 10, the cross-sectional reduced portion 132 is located at the middle portion, but the cross-sectional reduced portion 132 can be provided at another portion 134 including an end portion. It can also be provided at intervals.

As shown in FIG. 11 in a cross-sectional state, the cross-sectional reduced portion 132 is compressed and deformed, so that the entire cross-sectional area becomes smaller than that of the portion 134 as molded, and
As-thickness t ₃ of the apparent molded, i.e. is smaller than the thickness t ₀ of the apparent before compressive deformation. The reason why the cross-sectional area of the cross-section reducing portion 132 is reduced is a natural result because the cross-section has been reduced, but the apparent plate thickness is reduced for the following reason.

Referring again to FIG. 5, the pitch P between the convex portions 78 adjacent to each other in the axial direction A of the hybrid pipe and the apparent plate thickness t are those when the hybrid pipe is formed. Here, the apparent plate thickness t is different from the actual plate thickness d as a result of adding the concave portion 76 and the convex portion 78 to the hybrid pipe. Now, the axial direction A
When a load is applied in a direction B intersecting with the horizontal direction, the hybrid pipe has the property of extending in the axial direction A as shown in FIG. Then, the apparent plate thickness fluctuates as the pitch fluctuates, and becomes t 'smaller than t. However, the actual thickness d does not substantially change. The pitch and the apparent plate thickness vary greatly as the amount of compressive deformation of the hybrid pipe increases.

Referring to FIG. 12, which shows the energy absorption characteristics of the load F versus the displacement S, the portion 134 where the hybrid pipe 130 remains formed exhibits a predetermined energy absorption characteristic. On the other hand, in the cross-sectional reduction portion 132, the rise of the load F is slow, the peak value _{Fmax of the} load is small, and the displacement S
Also less. Since the rise and peak value of the load F depend on the apparent plate thickness, and the apparent plate thickness is determined by the amount of compression, the amount of compression of the cross-sectional reduction portion 132 is changed according to the energy absorption characteristics to be provided to the cross-section reduction portion 132. The energy absorption characteristics can be adjusted. FIG. 12 shows the amount of energy capable of absorbing shock.

In the embodiment shown in FIG.
32 was obtained by uniformly compressing and deforming all four surfaces of the rectangular hybrid pipe 130. In the embodiment shown in FIG. 13 in a perspective state, the hybrid pipe 1
Reference numeral 40 denotes a cross-sectional reduction portion 142 obtained by compressing two opposing surfaces from the outside. When formed in this manner, the hybrid pipe 140 exhibits the same energy absorption characteristics as the portion 144 having no cross-sectional reduced portion with respect to the load in the C direction, but the energy absorption with the apparent thickness reduced with respect to the load in the D direction. Thus, characteristics can be exhibited, and so-called directivity can be provided.

In the embodiment shown in FIG. 10 and FIG. 13, the hybrid pipe is compressed from the outer peripheral side to form a reduced section, and a reduced thickness section having an apparent reduced thickness is obtained. Conversely, the hybrid pipe formed in a constant cross section may be partially expanded from the inner peripheral side to form an enlarged cross section in which the cross section is enlarged, and this may be used as a reduced thickness portion. For example, referring to FIG.
2 is a constant cross section, and the portion 134 is an enlarged cross section. To partially expand the hybrid pipe from the inner circumferential side, the hybrid pipe section 13 is placed in a mold having a cross section larger than that of the formed hybrid pipe.
4, a bag formed of an elastic material such as rubber is inserted into the inside of the portion 134, and pressurized fluid is guided to the bag.

The hybrid pipe 150 shown in FIG. 14 in a perspective state and FIG. 15 in a cross-sectional state has an uneven portion 152 formed by continuously deforming a core material and front and back sheets in an axial direction. When there is no uneven deformation, plate thickness thickness t ₀ deformation before the apparent uneven portion 102, that is a flat-shaped plate thickness smaller than the thickness of the apparent as-formed reduced section 15
And 4. The thickness of the reduced thickness portion 154 is the actual thickness d of the hybrid pipe 150.

The hybrid pipe is formed, for example, by winding a core material and front and back sheets around a spindle to form a cylindrical body.
The cylindrical body is passed between the mold rollers to form irregularities with a predetermined pitch, and then, if necessary, is formed into a rectangular tube as shown in the drawing to obtain a product. Therefore, in order to form the hybrid pipe 150, the concave and convex portions 152 are surely provided with irregularities between the mold rollers, and the plate thickness reducing portion 154 does not operate the mold rollers or escapes the mold rollers so that the core material and the front and back surfaces can be formed. To form a cylindrical body, and then form a square tube as necessary.

When a load is applied from the direction B crossing the axial direction A, the apparent thickness is reduced in the uneven portion 152 in the axial direction, but the apparent thickness is reduced in the reduced thickness portion 154. However, the thickness is not substantially reduced. Load F vs. displacement S assuming that certain impact energy is absorbed
As shown in FIG.
Although 52 the rise of the load reaches a peak value F _max1 load becomes steep, when the rise of the load in the thickness reduction unit 154 reaches a peak value F _max2 of gradual and load, the peak value F _max2 is uneven portion 152 peak value F
less than _max1 . After the uneven portion 152 reaches the peak value,
As the displacement increases, the generated load gradually decreases, but the thickness-reduced portion 154 substantially maintains the peak value. This is because the apparent plate thickness gradually decreases in the uneven portion 152, while the plate thickness does not substantially change in the plate thickness reduction portion 154. On the other hand, regarding the displacement required to absorb a constant impact energy, when the length of the hybrid pipe 150 in the load direction is L, the actual thickness of the thickness reduction portion 154 is d. Decrease part 154
Then, the maximum displacement is (L-2d). On the other hand, assuming that the apparent plate thickness t ₀ of the uneven portion 152 does not change, the uneven portion 152 has a maximum displacement of (L−2t ₀ ).
However, since the hybrid pipe 150 elongates in the axial direction, the maximum displacement of the uneven portion 152 is changed by changing the allowable elongation as shown by a broken line to reduce the thickness of the hybrid pipe 150.
4 can be approached.

The hybrid pipe 160 shown in FIG. 17 in a perspective state and FIG.
2 and other uneven portions 164. Plate thickness reduction part 1
62, the thickness t ₄ of the apparent is the outer circumferential surface the inner peripheral surface the radial distance leading to the innermost recess 76 from outermost convex portion 78 is smaller than the thickness t ₀ of the apparent uneven portion 164, and, outer diameter D ₂ is the outer diameter D ₁ is smaller than the small size uneven part of the uneven portion 164. The hybrid pipe 160 is determined so that predetermined energy absorption characteristics can be obtained by the apparent plate thickness t ₀ of the uneven portion 164.

When a load is applied from the direction B intersecting the axial direction A, the thickness-reducing portion 162 and the uneven portion 164 extend in the axial direction, and the apparent thickness decreases. At this time, as shown in FIG. 19, the energy absorption characteristic of the load F versus the displacement S is such that the rise of the load becomes steep at the uneven portion 164 and reaches the peak value F _{max1 of the} load.
In the case of 2, the rise of the load is gradual and the peak value of the load F
_max2 , and this peak value is the peak value F of the uneven portion 164.
less than _max1 . After reaching the peak values of the plate thickness decreasing portion 162 and the uneven portion 164, the generated load gradually decreases as the displacement increases. The maximum displacement of the reduced thickness portion 162 is larger than the maximum displacement of the other uneven portions 164.

At the flat plate thickness reducing portion 154 (FIGS. 14 and 15) of the hybrid pipe 150, since the plate thickness does not substantially change, as shown in FIG. The difference between the peak values is larger than that of the portion 164, and the difference between the loads generated by the displacement is also larger. On the other hand, the reduced thickness portion 162 and the uneven portion 164 of the hybrid pipe 160 exhibit an approximate rising tendency and an approximate falling tendency. This indicates that the adjustment with the hybrid pipe 160 is easier than with the hybrid pipe 150 when adjusting the energy absorption characteristics of load versus displacement by providing a reduced thickness portion in the hybrid pipe.

Hybrid pipes 110, 130, 14
0, 150, and 160 reduced thickness portions 117 and 13 respectively
2, 142, 154, and 162 can be disposed at or near a structural member of the vehicle body that generates a large reaction load when an impact load is applied from the interior material. For example, it can be used as a plate thickness reducing portion described below.

Referring to FIG. 20 showing a perspective view from the back and FIG. 21 showing a perspective view, the pillar garnish 170 is provided with a mounting portion 171 for mounting the pillar garnish 170 to the pillar. Therefore, the reaction force load generated when an impact load is applied to the mounting portion 171 or the vicinity thereof is reduced to a portion 17 away from the mounting portion 171.
2 is higher than the reaction force load generated when an impact load is applied. That is, when a reaction force load is generated by adding the energy absorbing material 174 and the mounting portion 171 of the pillar garnish 170, when a hybrid pipe having substantially the same energy absorption characteristics is used, the mounting portion 17
At or near 1, a large reaction force load is generated.

[0078] With reference to FIGS. 22 and 23 show the energy absorption characteristics of the load F vs. displacement S, whereas is generating the hybrid pipe 171a high peak load F _p on the mounting portion 171, away from the mounting portion The peak load is low in the hybrid pipe 172a in the portion 172 that is located.
Therefore, placing the hybrid pipe with the same energy absorbing characteristics and portion 172 therefrom away from the mounting portion 171, and receive a high peak load F _p at the attachment portion 171 or the vicinity. On the other hand, the mounting portion 17
23, the energy absorption characteristic of the load F versus the displacement S becomes 171b in FIG. 23, which is substantially the same as the energy absorption characteristic 172a of the hybrid pipe in the portion 172 away from the mounting portion. The same energy absorption characteristics can be provided.

The reduced thickness portion may be provided at an intermediate portion as shown in FIG. 24 or a plurality of reduced thickness portions at intervals in the axial direction in addition to a portion generating a large reaction force load. Hybrid pipe 18 shown in FIG. 24 in a perspective state
Numeral 0 has a portion 182 where a predetermined load is to be generated, and a reduced thickness portion 184 provided at an intermediate portion of the portion 182. Here, the intermediate portion may be a central portion of the hybrid pipe 180 or a portion distant from the central portion. On the other hand, the hybrid pipe 190 shown in FIG. 25 in a perspective state has a portion 192 where a predetermined load is to be generated.
And a plurality of thickness reduction portions 194, and the thickness reduction portion 1
Numerals 94 are arranged at predetermined intervals in the axial direction of the hybrid pipe 190. In this case, the plurality of reduced thickness portions 194 need not be the same length. Although the hybrid pipes 180 and 190 are formed in specific shapes corresponding to the front pillars and the roof side rails, respectively, as described above, the hybrid pipes are appropriate depending on where they are disposed. The shape itself has no meaning in terms of energy absorption characteristics. 24 and 25, the thickness-reducing portion 18 is used.
4, 194 is the form of the reduced thickness portion 132 shown in FIG. 10, but instead of this, the reduced thickness portion 142 of FIG. 13, the reduced thickness portion 154 of FIG. 14, or the reduced thickness portion of FIG. 162
Can also be used.

Referring to FIG. 26 schematically shown, hybrid pipe 130 ((a) in FIG. 26) having a reduced thickness portion 132 having a reduced cross section in the middle portion, and a flat reduced thickness portion 154. 150 having an intermediate portion in the middle
((B) of the figure) and the small-sized uneven portion are replaced with the thickness-reducing portion 162.
And a hybrid pipe 160 having this in the middle
The operation of ((c) in the figure) and the hybrid pipe 200 ((d) in the figure) that does not have the reduced thickness portion will be described.

Hybrid pipe 1 having reduced thickness portion
When attached to a structural member or an interior material so as not to restrict the reduced thickness portion, the members 30, 150, and 160 deform and absorb energy as already described with respect to an impact load applied from a direction intersecting the axis. On the other hand, when an axial load P is applied, the hybrid pipes 130, 150, 160
Are, as shown on the lower side of each figure, the thickness reduced portions 132, 15
It bends at 4,162. Once the hybrid pipes 130, 150, and 160 bend at the reduced thickness portion, the portions located on the left and right across the reduced thickness portion approach each other without deforming necessary for energy absorption. It exhibits a tendency to exhibit a very low load-to-displacement energy absorption characteristic with respect to the load P. This means that the energy absorption characteristics can be made significantly different depending on the direction in which the load is applied, thereby providing directivity. On the other hand, in the hybrid pipe 200 having no reduced thickness portion, when the load P in the axial direction is applied, the whole of the pipe is curved in an arc shape, and is simultaneously compressed and deformed in the axial direction. Since the energy is absorbed by the compressive deformation in the axial direction, the difference in the energy absorption characteristics due to the difference in the direction in which the load of the hybrid pipe 200 is applied is smaller than in FIGS. 26 (a) to (c).

In the case of the hybrid pipe 190, when a load in a direction intersecting the axis is applied from the spherical impact body 210 as shown in FIG. 27A schematically, the portion 196 where the load is applied is sandwiched. Plate thickness reduction portions 19 located on both sides
4, the portion 196 and the reduced thickness portions 194 located on both sides are curved and compressed in substantially the same manner as the curved surface of the impact body 210 as shown in the lower side of FIG. Other parts hardly deform. As a result, even if a load in the direction intersecting the axis line is applied again to another portion distant from the portion 196, the intended energy absorption characteristic of load versus displacement can be exhibited in the other portion. On the other hand, in the hybrid pipe 200 having no thickness reduction portion, the hybrid pipe 200 is extended by the impact body 210 as shown in FIG.
The entire hybrid pipe 200 is curved and compressively deformed. As a result, as compared with the portion 202 to which the load is applied, for example, in the end portion 204, the amount of displacement that can be ensured fluctuates, so that the intended load-displacement energy absorption characteristic cannot be obtained.

The impact energy absorbing material according to the present invention is shown in FIGS. 8, 10, 13, 14, 15, 15, 17, 18, 21, and 24, again. Referring to FIG. 25, hybrid pipes 110, 130, 1 each comprising a metal foil core material 72 and sheets 74 of a material other than metal superposed on the front and back surfaces of the core material 72, respectively.
40, 150, 160, 174, 180, 190. The hybrid pipe is formed so as to be continuously deformed into an uneven shape in the axial direction, and is formed such that the apparent thickness is partially different in the axial direction, for example, as shown in FIG. The impact energy absorbing material is disposed between the structural member and the interior material, for example, in an upper part of the vehicle body having the structural member and the interior material, and forms an impact energy absorbing structure.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view showing an essential part of an embodiment of a hybrid pipe used for an impact energy absorbing structure on an upper part of a vehicle body according to the present invention, which is cut along an axial direction of the hybrid pipe.

FIG. 2 is a perspective view showing an embodiment of a hybrid pipe used for an impact energy absorbing structure on an upper part of a vehicle body according to the present invention.

FIG. 3 is a perspective view showing another embodiment of the hybrid pipe used in the impact energy absorbing structure on the upper part of the vehicle body according to the present invention.

FIG. 4 is an energy absorption characteristic diagram of load versus displacement.

FIG. 5 is a sectional view for explaining the operation and effect of the present invention;
(A) shows the state before deformation, and (b) shows the state after deformation.

FIGS. 6A and 6B are schematic diagrams for comparing the operation and effect of the hybrid pipe with the extruded pipe, wherein FIG.
Shows the state of deformation of the hybrid pipe, and (c) shows the state of deformation of the extruded pipe.

FIG. 7 is an energy absorption characteristic diagram of load versus displacement, and (a)
Indicates a hybrid pipe, and (b) indicates an extruded pipe.

FIG. 8 is an enlarged cross-sectional view showing a main part of another embodiment of a hybrid pipe used for an impact energy absorbing structure on an upper part of a vehicle body according to the present invention, which is cut along an axial direction of the hybrid pipe.

FIG. 9 is an energy absorption characteristic diagram of load versus displacement.

FIG. 10 is a perspective view showing still another embodiment of the hybrid pipe used in the impact energy absorbing structure on the upper part of the vehicle body according to the present invention.

11 is a cross-sectional view of the hybrid pipe shown in FIG. 10, in which (a) is a section taken along line 11a-11a in FIG. 10, and (b) is a section taken along line 11b-11b in FIG.

FIG. 12 is an energy absorption characteristic diagram of load versus displacement.

FIG. 13 is a perspective view showing still another embodiment of the hybrid pipe used in the impact energy absorbing structure on the upper part of the vehicle body according to the present invention.

FIG. 14 is a perspective view showing still another embodiment of the hybrid pipe used in the impact energy absorbing structure on the upper part of the vehicle body according to the present invention.

FIG. 15 is an enlarged vertical sectional view taken along line 15-15 of FIG.

FIG. 16 is an energy absorption characteristic diagram of load versus displacement.

FIG. 17 is a perspective view showing still another embodiment of the hybrid pipe used in the impact energy absorbing structure on the upper part of the vehicle body according to the present invention.

18 is an enlarged vertical sectional view taken along line 18-18 of FIG.

FIG. 19 is an energy absorption characteristic diagram of load versus displacement.

FIG. 20 is a perspective view of a pillar garnish to which a hybrid pipe is attached, as viewed from the back.

FIG. 21 is a perspective view showing a part of the hybrid pipe shown in FIG. 20.

FIG. 22 is an energy absorption characteristic diagram of load versus displacement.

FIG. 23 is an energy absorption characteristic diagram of load versus displacement.

FIG. 24 is a perspective view showing a hybrid pipe for a front pillar.

FIG. 25 is a perspective view showing a hybrid pipe for a roof side rail.

FIG. 26 is a schematic diagram showing the operation and effect of the hybrid pipes (a) to (c) in which the plate thickness reduced portion is arranged in the middle portion in comparison with the hybrid pipe (d) having no plate thickness reduced portion; In each figure, the upper side shows the state before deformation, and the lower side shows the state after deformation.

FIG. 27 is a schematic diagram showing the operation and effect of a hybrid pipe (a) in which a plurality of thickness-reducing portions are arranged at intervals in the axial direction in comparison with a hybrid pipe (b) having no thickness-reducing portion. In each figure, the upper side is before deformation,
The lower side shows the state after deformation.

FIG. 28 is an enlarged sectional view of the upper part of the vehicle body in which the impact energy absorbing structure according to the present invention can be implemented, which is cut along line 28-28 in FIG.

FIG. 29 is an enlarged cross-sectional view of the upper part of the vehicle body in which the impact energy absorbing structure according to the present invention can be implemented, which is cut along the line 29-29 in FIG.

FIG. 30 is a perspective view of an upper portion of a vehicle body in which the impact energy absorbing structure according to the present invention can be implemented.

[Explanation of symbols]

70, 90, 110, 130, 140, 150 Hybrid pipe 160, 174, 180, 190 Hybrid pipe 72 Core material 74 Sheet 76 Concave portion 78 Convex portion 81 Large pitch uneven portion 117, 132, 142 Reduced thickness (cross-section reduced portion) ) 154 Reduced thickness (flat reduction portion) 162 Reduced thickness (small dimension unevenness) 175, 184, 194 Reduced thickness

Claims (14)

[Claims] An impact energy is absorbed in an upper portion of a vehicle body including a structural member of a vehicle body, an interior material disposed inside the structural member at a distance, and an energy absorbing material disposed within the distance. Wherein the energy absorbing material is a hybrid pipe composed of a core material of a metal foil and a sheet of a material other than metal superimposed on each of the front and back surfaces of the core material. And the front and back sheets are formed by continuously deforming in an uneven manner in the axial direction, and the pitch between two convex portions or concave portions located adjacent to each other in the axial direction is partially different in the axial direction. Formed in the
Impact energy absorbing structure at the top of the vehicle. 2. The hybrid pipe has an uneven portion having a predetermined pitch and a large pitch uneven portion having a pitch larger than the pitch of the uneven portion, and the large pitch uneven portion is arranged at an intermediate portion of the hybrid pipe. The impact energy absorbing structure for an upper part of a vehicle body according to claim 1. 3. The hybrid pipe has an uneven portion having a predetermined pitch and a plurality of large pitch uneven portions having a pitch larger than the pitch of the uneven portion, and the large pitch uneven portion extends in the axial direction of the hybrid pipe. The impact energy absorbing structure according to claim 1, wherein the impact energy absorbing structure is arranged at a predetermined interval. 4. A hybrid pipe comprising a core material of a metal foil and sheets of a material other than metal superposed on the front and back surfaces of the core material, respectively. Is formed by continuously deforming the protrusions and recesses in the axial direction, and formed so that the pitch between two convex portions or concave portions located adjacent to each other in the axial direction is partially different in the axial direction. Energy absorber. 5. Absorbing impact energy in an upper part of a vehicle body comprising a structural member of a vehicle body, an interior material disposed inside the structural member at a distance, and an energy absorbing material disposed within the distance. Wherein the energy absorbing material is a hybrid pipe composed of a core material of a metal foil and a sheet of a material other than metal superimposed on each of the front and back surfaces of the core material. And the front and back sheets are continuously deformed in the axial direction into an uneven shape, and the apparent thickness is formed to be partially different in the axial direction. 6. The vehicle body according to claim 5, wherein the hybrid pipe has an uneven portion having a predetermined apparent thickness and a reduced thickness portion having an apparent thickness smaller than the apparent thickness of the uneven portion. Upper impact energy absorbing structure. 7. The impact energy absorbing structure for an upper part of a vehicle body according to claim 6, wherein said reduced thickness portion is a cross-sectional reduced portion obtained by compressing a hybrid pipe formed in a fixed cross section from the outer peripheral side to reduce the cross section. 8. The impact energy absorbing structure for an upper part of a vehicle body according to claim 6, wherein the reduced thickness portion is a cross-sectional enlarged portion obtained by expanding a cross section by expanding a hybrid pipe formed in a fixed cross section from an inner peripheral side. . 9. The hybrid pipe has an uneven portion having a predetermined radial dimension intersecting with the axial direction, and a small dimension uneven portion having a radial dimension smaller than the radial dimension of the uneven section. 7. The impact energy absorbing structure on the upper part of the vehicle body according to claim 6, wherein the small-sized uneven portion serves as the plate thickness reduced portion. 10. Absorbing impact energy in an upper part of a vehicle body comprising a structural member of a vehicle body, an interior material disposed inside the structural member at a distance, and an energy absorbing material disposed within the distance. Wherein the energy absorbing material is a hybrid pipe composed of a core material of a metal foil and a sheet of a material other than metal superimposed on the front and back surfaces of the core material, respectively. And the front and back sheets and the uneven portion having a predetermined apparent thickness formed by continuously deforming the sheet in the axial direction into an uneven shape, and the sheet thickness is smaller than the apparent thickness of the uneven portion without any uneven deformation. Having a small flat plate thickness reduction portion,
Impact energy absorbing structure at the top of the vehicle. 11. The plate thickness reducing portion is disposed at or near a structural member of a vehicle body that generates a large reaction force load when an impact load is applied via the interior material. The impact energy absorbing structure of the upper part of the vehicle body according to any one of the above. 12. The impact energy absorbing structure for an upper part of a vehicle body according to claim 6, wherein said reduced thickness portion is provided at an intermediate portion in an axial direction of said hybrid pipe. 13. The impact energy absorbing structure on an upper part of a vehicle body according to claim 6, wherein a plurality of said thickness reducing portions are provided, and are arranged at predetermined intervals in an axial direction of said hybrid pipe. . 14. A hybrid pipe comprising a core material of a metal foil and sheets of a material other than metal superposed on the front and back surfaces of the core material, respectively. The impact energy absorbing material is formed by continuously deforming in the axial direction into an uneven shape, and formed such that the apparent plate thickness is partially different in the axial direction.