JP2011110954A - Vehicle panel - Google Patents

Abstract

An object of the present invention is to provide a lightweight vehicle panel having an inner panel whose rigidity is improved by providing a concavo-convex portion on a single plate and having excellent shock absorbing performance at the time of a primary collision and a secondary collision.
An uneven portion 20 of an inner panel 2 includes a first projecting portion 21 having a 12-pyramidal shape or a truncated pyramid shape, and a second projecting portion exhibiting a hexagonal pyramid shape or a hexagonal truncated pyramid shape projecting to the opposite side. 22 and an intermediate plane 23 which is a quadrangular plane. When viewed from the vertical direction, the first protrusions 21 are regularly distributed corresponding to the positions of the center point and each vertex of one substantially regular hexagon of the virtual substantially regular hexagons. Six second protrusions 22 and six intermediate planes 23 are alternately and regularly arranged so as to surround the periphery of the one protrusion 21, and the intermediate planes 23 connect adjacent first protrusions 21 to each other. The second protrusions 22 are distributed and arranged at positions surrounded by the first protrusions 22 and the intermediate plane 23.
[Selection] Figure 3

Description

  The present invention relates to a vehicle panel mainly composed of an outer panel and an inner panel.

  Vehicle panels such as automobile hoods and doors are generally configured by laminating an outer panel and an inner panel. In recent years, for the purpose of weight reduction, it has been studied and implemented to replace a material of a part made of a steel plate or the like with a light material made of an aluminum alloy plate. In this case, it is necessary to ensure the required rigidity as a premise for weight reduction. The Young's modulus of the aluminum alloy is about 1/3 of the Young's modulus of the steel plate, and in order to maintain the same rigidity as that of the steel plate, it is necessary to increase the plate thickness or to form a shape with high rigidity. Among these, increasing the plate thickness goes against weight reduction, so that a shape having high rigidity is generally given.

Until now, as an inner panel made of an aluminum alloy plate, a beam-type panel and a cone-type panel are well known (see Patent Documents 1 to 3).
Patent Document 1 proposes a beam-type inner panel shape. Patent Document 2 proposes a cone-shaped inner panel shape. Patent Document 3 proposes a cone-type panel shape using two inner panels.

Japanese Patent No. 4287614 Japanese Patent No. 3829715 Japanese Patent No. 4336079

It is known that the beam-type inner panel of Patent Document 1 has lower torsional rigidity than the cone-type inner panel of Patent Document 2.
The convex part of the inner panel of the above-mentioned patent document 2 is the top part on the outer panel side, and the impact absorption performance when there is a secondary collision with the engine or the like is lower than the inner panel combined with two of the above-mentioned patent document 3. It is known.

  On the other hand, since the inner panel of Patent Document 3 is composed of two sheets, the number of parts is increased and the assembly cost is increased compared to the case of one sheet of Patent Documents 1 and 2, and the number of parts. There is a drawback that the weight increases by the amount of increase.

  The present invention has been made in view of such conventional problems, and is a vehicle panel provided with an inner panel whose rigidity is improved by providing an uneven portion on a single plate, and includes a primary collision and a secondary collision. It is an object of the present invention to provide a lightweight vehicle panel that is excellent in impact absorption performance at the time of collision.

The present invention provides a vehicle panel having an outer panel made of an aluminum alloy plate and an inner panel made of an aluminum alloy plate arranged toward the back surface of the outer panel.
The inner panel has an uneven portion protruding in the thickness direction,
The concavo-convex portion is based on an intermediate reference plane that is a virtual plane,
A first protrusion having a 12 pyramid shape or a 12 pyramid shape having a base on the intermediate reference plane;
A second projecting portion having a base on the intermediate reference plane and projecting to the opposite side of the first projecting portion, or a hexagonal pyramid shape or a hexagonal pyramid shape;
An intermediate plane that is a quadrangular plane provided on the intermediate reference plane,
When viewed from the vertical direction of the intermediate reference plane, the first protrusion corresponds to the position of the center point of each substantially regular hexagon of the virtual substantially regular hexagons constituting the entire plate surface in a lattice shape and the positions of the vertices. The six second protrusions and the six intermediate planes are alternately and regularly arranged so as to surround the periphery of the one first protrusion.
The intermediate plane is distributed and arranged so as to connect the adjacent first protrusions, and the second protrusion is distributed and disposed at a position surrounded by the first protrusion and the intermediate plane. It is in the vehicle panel characterized by the above-mentioned (Claim 1).

  The said uneven part in the vehicle panel of this invention has the uneven part of the said special shape. The first projecting portion and the second projecting portion project in opposite directions, and the intermediate plane is dispersedly arranged so as to connect adjacent first projecting portions, and the second projecting portion is Dispersed and arranged at positions surrounded by the first protrusion and the intermediate plane. Therefore, at the position where the intermediate plane and the first protrusion or the second protrusion are adjacent, the side surfaces of the first protrusion or the second protrusion that are not parallel to the intermediate plane surround the intermediate plane, and In a portion where the first protrusion and the second protrusion are adjacent, these side surfaces form a surface in a direction that obliquely penetrates the intermediate reference surface. By realizing such a shape, the inner panel becomes a highly rigid material having excellent bending rigidity.

  Further, as described above, the uneven portion realizes a regular dispersed arrangement by making the outer shape of each of the first projecting portion, the second projecting portion, and the intermediate plane into a dodecagon, a hexagon, and a tetragon, respectively. is doing. Thereby, the characteristic with no directivity is exhibited as a whole, and the effect of improving the rigidity is obtained in any direction.

The vehicle panel of the present invention is configured by using the inner panel having such excellent rigidity and facing the outer panel to the first projecting portion or the second projecting portion and joining at least the periphery. In the vehicle panel, the impact of the primary collision when the pedestrian collides is absorbed by the first protrusion or the second protrusion that protrudes toward the outer panel, and the impact of the secondary collision to the engine or the like is the second. The protrusion or the first protrusion absorbs. The intermediate region existing on the intermediate reference plane, the first projecting portion, and the second projecting portion are present in the special positional relationship so that there is almost no directivity, and the primary collision and the second projecting in any direction. The impact absorption performance of the next collision can be improved to the same level or higher.
Moreover, the vehicle panel of the present invention is composed of an outer panel made of one aluminum alloy plate and an inner panel made of one aluminum alloy plate, and is significantly lighter than a conventional steel plate vehicle panel. can do.

  Therefore, according to the present invention, it is possible to provide a vehicle panel that is light in weight and has shock absorption performance at the time of primary collision and secondary collision that are equal to or higher than those of the conventional one.

Explanatory drawing which shows the structure of the vehicle panel in Example 1. FIG. The partial top view of the uneven | corrugated | grooved part in Example 1. FIG. The partial perspective view of the uneven | corrugated | grooved part in Example 1. FIG. FIG. 3 is a cross-sectional view taken along line AA in FIG. FIG. 3 is a cross-sectional view taken along the line BB in FIG. The partial top view of the uneven | corrugated | grooved part in Example 2. FIG. The partial perspective view of the uneven | corrugated | grooved part in Example 2. FIG. FIG. 7 is a cross-sectional view taken along line AA in FIG. FIG. 7 is a sectional view taken along line BB in FIG. The shape of one 1st protrusion part in Example 2 is shown, (a) Top view, (b) Perspective view, (c) Front view. The shape of one 2nd protrusion part in Example 2 is shown, (a) Top view, (b) Perspective view, (c) Front view. The partial top view of the uneven | corrugated | grooved part in Example 3. FIG. The partial perspective view of the uneven | corrugated | grooved part in Example 3. FIG. FIG. 13 is a cross-sectional view taken along line AA in FIG. FIG. 13 is a sectional view taken along line BB in FIG. The partial top view of the uneven | corrugated | grooved part in Example 4. FIG. The partial perspective view of the uneven | corrugated | grooved part in Example 4. FIG. The partial top view of the uneven | corrugated | grooved part in Example 4 when there is no 1st plane and 2nd plane. The partial perspective view of the uneven | corrugated | grooved part in Example 4 when there is no 1st plane and 2nd plane.

  In the present invention, expressions such as a dodecagon, a hexagon, a quadrangle, a 12 pyramid, a hexagonal pyramid, a 12 pyramid, a hexagonal pyramid, etc. As a matter of course, it is permissible for each side to be slightly curved, to have roundness at each vertex, and to have roundness necessary for molding at corners and surfaces.

Further, at least one of the first projecting portion and the second projecting portion includes a base projecting portion projecting a predetermined amount from a bottom portion on the intermediate reference plane, and a plane formed at the apex portion of the base projecting portion. It can be set as the structure which has the 1 step | paragraph shape which has (Claim 2).
When one or both of the first projecting portion and the second projecting portion have the above-described one-stage shape, it is easier to reduce the amount of protrusion than in the case of a multi-stage shape to be described later, and there is a thickness limitation. This is effective in efficiently obtaining the rigidity improvement effect. In the case of the one-stage shape, the first projecting portion has a 12-sided truncated pyramid shape without a bent portion whose inclination angle changes in the middle of the side surface. Similarly, in the case of the one-stage shape, the second protrusion has a hexagonal truncated pyramid shape that does not have a bent portion whose inclination angle changes in the middle of the side surface (see Example 1).

Further, at least one of the first projecting portion and the second projecting portion includes a base projecting portion projecting a predetermined amount from a bottom portion on the intermediate reference plane, and an extended projecting portion having a different inclination angle from the base projecting portion. It is also possible to adopt a configuration in which a plurality of continuous stages are formed (claim 3).
When the multi-stage shape is adopted, a further rigidity improvement effect can be expected due to the presence of the extended protrusion. In the case of a two-stage shape, the first protrusion has a two-stage 12-sided pyramid shape or a 12-sided truncated pyramid shape having a bent portion whose side surface inclination angle changes at the boundary between the basic protrusion and the extended protrusion. Similarly, in the case of a two-stage shape, the second projecting portion has a two-stage hexagonal pyramid shape or a hexagonal pyramid shape having a bent portion in which the inclination angle of the side surface changes at the boundary between the basic projecting portion and the extended projecting portion. (See Example 2). Note that a multi-step shape of three or more steps can be realized by further providing a bent portion in the middle of the extended protruding portion.

In addition, it is preferable that the first projecting portion and the second projecting portion have the same inclination angle of the basic projecting portions of the first projecting portion and the second projecting portion. In this case, since the inclination angles of the base protrusions are the same (see Examples 1 to 3), the base protrusions at the position where the first protrusions and the second protrusions are adjacent to each other are one. It will be continuous on a flat surface and molding will be easy.
In addition, it is also possible to adopt a structure in which a bent portion is provided on the intermediate reference plane with the inclination angle of the base protrusion portion of the first protrusion portion and the inclination angle of the second protrusion portion different from each other (Example) 4).

  Moreover, it is preferable that the inclination | tilt angle with respect to the said intermediate | middle reference plane of the side surface of the said extension protrusion part exists in the range of 5 degrees-60 degrees. When the inclination angle of the side surface of the extended protrusion is less than 5 °, the effect of improving the rigidity is less than that of 0 °, that is, a flat surface. On the other hand, when the inclination angle of the side surface of the extended protrusion exceeds 60 °, there is a problem that molding becomes difficult.

  Moreover, it is preferable that the inclination | tilt angle with respect to the said intermediate | middle reference plane of the said base protrusion part exists in the range of 10 degrees-90 degrees (Claim 6). When the inclination angle of the basic protrusion is less than 10 °, there is a problem that the effect of improving the rigidity is small. On the other hand, when the inclination angle of the basic protrusion exceeds 90 °, it is difficult to form the concavo-convex portion and is an unnecessary region.

  The inner panel preferably has a thickness t of 0.3 mm to 2.0 mm before the formation of the concavo-convex portion. By setting the thickness t of the inner panel within the above range, excellent rigidity can be obtained while ensuring workability. On the other hand, when the plate thickness t is less than 0.3 mm, it is difficult to obtain rigidity necessary for use, and when the plate thickness t exceeds 2.0 mm, molding becomes difficult. In addition, the reason prescribed | regulated by the plate | board thickness t before uneven | corrugated | grooved part formation is because the plate | board thickness of each part may change by processing the said uneven | corrugated | grooved part by plastic processing, such as press work and roll molding.

Further, the ratio (H ₁ / t) between the projection height H ₁ (mm) of the _first projection from the intermediate reference plane and the plate thickness t (mm) before forming the concavo-convex portion is the first projection. 1 ≦ H ₁ /t≦−2.5θ ₁ +227 in relation to the largest inclination angle θ ₁ (°) on the side surface of the second side, and the protrusion height of the second protrusion from the intermediate reference surface The ratio (H ₂ / t) of H ₂ (mm) to the plate thickness t (mm) is 1 ≦ H _{2 in} relation to the largest inclination angle θ ₂ (°) on the side surface of the second protrusion. It is preferable that the relationship is /t≦−2.5θ ₂ +227.

When the ratio (H ₁ / t) is less than 1, there is a risk that the effect of improving the rigidity is less than when the ratio is not projected, whereas the ratio (H ₁ / t) exceeds −2.5θ ₁ +227 In some cases, molding may be difficult.
Further, when the ratio (H ₂ / t) is less than 1, there is a fear that the effect of improving the rigidity is less than when the ratio is not projected, whereas the ratio (H ₂ / t) is −2.5θ ₂ +227. If it exceeds, molding may be difficult.

In addition, a ratio (D ₁₁ / t) between the outer dimension D ₁₁ (mm) of the first protrusion and the plate thickness t (mm) before forming the uneven part is 10 to 500, and the bottom of the second protrusion It is preferable that the ratio (D ₂₁ / t) of the outer dimension D ₂₁ (mm) of the portion to the plate thickness t (mm) is 10 to 500 (claim 9).

If the ratio (D ₁₁ / t) is less than 10, molding may be difficult. On the other hand, if the ratio (D ₁₁ / t) exceeds 500, the concavo-convex unit shape becomes too large. In practical use, it may be difficult to handle or the rigidity improvement effect may not be sufficiently obtained.
Further, when the ratio (D ₂₁ / t) is less than 10, molding may be difficult. On the other hand, when the ratio (D ₂₁ / t) exceeds 500, the concavo-convex unit shape becomes large. Therefore, it may be difficult to handle practically, or the rigidity improvement effect may not be sufficiently obtained.

The vehicle panel of the present invention is not limited to a hood of an automobile, and can be used as a panel for doors, roofs, floors, trunk lids, and the like.
As the aluminum alloy plate constituting the outer panel, for example, a 6000 series alloy plate is preferable because it is relatively inexpensive. Moreover, as an aluminum alloy plate which comprises the said inner panel, a 5000 type alloy plate is suitable for the reason that a moldability is comparatively good, for example.

Moreover, the said uneven | corrugated | grooved part can also be changed into the structure containing a rib structure as follows.
That is, it has one or a plurality of first rib portions having a first top surface portion that passes on a straight line or a curve connecting the vertex center portions of the plurality of first protrusions, and the first rib portions are formed in the planar shape. A first top surface portion, and a pair of left and right first side wall portions inclined so as to gradually expand from both side portions of the first top surface portion toward the intermediate reference surface, and the first cross section intersecting the first side wall portion The first protrusion is a deformed first protrusion limited to a narrow region up to a position where it intersects with the first side wall, and the second protrusion that intersects with the first side wall is a position where it intersects with the first side wall. The deformed second projecting portion limited to a narrow region up to, and the intermediate plane intersecting with the first side wall portion is a deformed intermediate plane limited to a narrow region up to a position intersecting with the first side wall portion. It can be configured.

  Also, it has one or a plurality of second rib portions having a second top surface portion passing through a straight line or a curve connecting the vertex center portions of the plurality of second protrusions, and the second rib portions are planar first And a pair of left and right second side wall portions inclined so as to gradually expand from both side portions of the second top surface portion toward the intermediate reference surface, and intersect the second side wall portion. The first protrusion is a deformed first protrusion limited to a narrow region up to a position where it intersects with the second side wall, and the second protrusion that intersects with the second side wall is a position where it intersects with the second side wall. The intermediate flat surface that intersects with the second side wall portion is a deformed intermediate plane that is confined to the narrow region up to a position that intersects with the second side wall portion. It can be configured.

  In these cases, by providing at least one of the first rib portion and the second rib portion, it is easy to adjust the impact force when a pedestrian collides, compared to a case where this is not provided. That is, it is possible to easily change the design of the impact force by changing the range, number, shape and the like of the first rib portion or the second rib portion.

Example 1
A vehicle panel according to an embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1, the vehicle panel 1 of this example is a vehicle panel having an outer panel 10 made of an aluminum alloy plate and an inner panel 2 made of an aluminum alloy plate arranged toward the back surface of the outer panel 10. is there. The inner panel 2 is joined to the outer panel 10 at the outer peripheral portion by hem processing or the like. In addition, it can also join in arbitrary places other than an outer peripheral part.

The outer panel 10 is made of an aluminum alloy plate having a material of 6000 series and a plate thickness of 1.0 mm.
The inner panel 2 is made of an aluminum alloy plate having a material of 5000 series and a thickness t before forming the unevenness of 0.9 mm.

  As shown in FIG. 1, the inner panel 2 has a concavo-convex portion 20 protruding in the thickness direction at a central portion excluding the outer peripheral portion. In this example, the concavo-convex portion 20 of the inner panel 2 was formed by press molding using a pair of molds. In addition, this shaping | molding method can also employ | adopt other plastic processing methods, such as roll shaping | molding formed with a pair of shaping | molding roll which gave the desired uneven | corrugated shape on the surface. The concavo-convex portion 20 is configured as follows.

  As shown in FIGS. 4 and 5, the concavo-convex portion 20 is based on the intermediate reference plane K <b> 3 that is one virtual plane, and has a first projecting portion 21 that has a 12-sided truncated pyramid shape having a base on the intermediate reference plane K <b> 3. And a second protrusion 22 having a hexagonal truncated pyramid shape having a base on the intermediate reference plane K3 and protruding on the opposite side of the first protrusion 21, and a quadrangular shape provided on the intermediate reference plane K3. And an intermediate plane 23 which is a plane.

As shown in FIG. 2, when viewed from the vertical direction of the intermediate reference plane K3, the first projecting portion 21 has a regular hexagonal center point a and each vertex of a virtual regular hexagon that forms the entire plate surface in a lattice shape. The second projecting portions 22 and the six intermediate planes 23 are alternately and regularly arranged so as to surround the periphery of the first projecting portion 21. ing. The intermediate planes 23 are distributed and arranged so as to connect the adjacent first protrusions 21, and the second protrusions 22 are distributed and arranged at positions surrounded by the first protrusions 21 and the intermediate plane 23. . This arrangement is regularly arranged in all directions.
Further details will be described below.

As described above, the inner panel 2 of the present example is made of a 5000 series aluminum alloy having a thickness t of 0.9 mm before the uneven portion formation. It should be noted that dimensions such as thickness in the figure are emphasized for convenience of explanation and are not accurate. 2 and 3, the boundary between the first protrusion 21 and the second protrusion 22 that does not actually appear in appearance is indicated by a broken line P (FIGS. 6, 7, 12, and 12 described later). 13 is the same). FIG. 2 is a plan view of a partial range of the uneven portion 20.
The uneven portion 20 is formed by press molding using a pair of molds. In addition, as this shaping | molding method, it is also possible to employ | adopt other plastic processing methods, such as roll shaping | molding formed with a pair of shaping | molding roll which gave the desired uneven | corrugated shape on the surface.

As shown in FIGS. 2 to 5, the first projecting portion 21 is formed on the first base projecting portion 211 projecting a predetermined amount from the bottom portion on the intermediate reference plane K <b> 3 and the top portion of the first base projecting portion 211. It has a single-stage 12-sided truncated pyramid shape having a first plane 215. The side surface of the first basic protrusion 211 is inclined at an inclination angle α with respect to the intermediate reference plane K3, and the first flat surface 215 at the top is an imaginary portion arranged in parallel with a distance S ₁ from the intermediate reference plane K3. It is arranged on the first reference plane K1. In this example, the inclination angle α = 45 ° and the interval S ₁ = 6 mm. The interval S ₁ matches the protrusion amount H ₁ of the first protrusion 21. Therefore, the ratio (H ₁ / t) between the protrusion height H ₁ (mm) of the first protrusion 21 from the intermediate reference plane K3 and the plate thickness t (mm) before the formation of the uneven portion is 6.7.

The second protrusion 22 includes a second base protrusion 221 that protrudes a predetermined amount from the bottom on the intermediate reference plane K3, and a second flat surface 225 formed on the top of the second base protrusion 221. It has a stepped hexagonal truncated pyramid shape. The side surface of the second base protrusion 221 is inclined by an inclination angle β with respect to the intermediate reference plane K3, and the second flat surface 225 at the top is an imaginary portion arranged in parallel with a distance S ₂ from the intermediate reference plane K3. It is arranged on the second reference plane K2. In this example, the inclination angle β = 45 ° and the interval S ₂ = 6 mm. The interval S ₂ matches the protrusion amount H ₂ of the second protrusion 22. Therefore, the ratio (H ₂ / t) between the protrusion height H ₂ (mm) of the second protrusion 22 from the intermediate reference plane K3 and the plate thickness t (mm) before forming the uneven portion is 6.7.

  As shown in FIGS. 4 and 5, the side surfaces of the first base protrusions 211 of the adjacent first protrusions 21 and the side surfaces of the second base protrusions 221 of the second protrusions 22 have the same inclination angle as described above. Therefore, it shows a form of being connected by one plane, and a bent portion or the like on the appearance does not appear on the intermediate reference plane K3. 2 and 3 are shown by the broken line P as described above.

As shown in FIG. 2, the outer dimension D ₁₁ of the first protrusion 21 is 125 mm, and the ratio (D ₁₁ / t) to the plate thickness t (mm) before forming the uneven portion is 138.9. The outer dimension D ₂₁ of the bottom side of the second protrusion 22 is 94 mm, and the ratio (D ₂₁ / t) to the plate thickness t (mm) is 104.4.

  As described above, the inner panel 2 of the present example includes the uneven portion 20 having a special shape having three regions, ie, the first protruding portion 21, the second protruding portion 22, and the intermediate plane 23. Therefore, the inner panel 2 is a highly rigid material having excellent bending rigidity. And as shown in FIG. 1, the vehicle panel 1 excellent in the shock absorption performance is obtained by combining the inner panel 2 and the outer panel 10. Moreover, since the vehicle panel 1 of this example is made of an aluminum alloy plate, the weight can be reduced.

(FEM analysis)
FEM (finite element method) analysis for quantitatively judging the rigidity improvement effect of the inner panel 2 of this example was performed.
The FEM analysis method assumes a cantilever with one end Z1 of the test piece consisting only of the concavo-convex portion 20 having the size shown in FIG. 3 and the other end Z2 as a free end, and applies a load of 1 N to the free end. Rigidity is obtained from the amount of deflection when applied. The size of the test piece was 300 mm × 346 mm, and the plate thickness t before press forming the concavo-convex portion 20 was 0.9 mm, and after the forming, 0.8 mm.
The evaluation of the rigidity was performed based on the ratio of the bending amount obtained as a result of the same FEM analysis performed on the flat base plate before the formation of the concavo-convex part 20, and by how many times the rigidity was improved. As a result, it was found that the concavo-convex portion 20 of this example was improved in rigidity by 7.1 times compared to the case of a flat base plate.

(Example 2)
In this example, the shape of the concavo-convex portion is changed from that in the first embodiment. However, it is made of a 5000 series aluminum alloy having a thickness t of 0.9 mm before the uneven portion formation. As shown in FIGS. 6 to 11, the uneven portion 202 of the present example includes a first protrusion 21 that protrudes in one direction in the thickness direction, a second protrusion 22 that protrudes in the other direction, and an intermediate plane located between them. 23. For convenience of explanation, the same reference numerals as in Example 1 are used for parts of the same type even if the shapes are different (hereinafter the same).

  As shown in FIG. 6, when viewed from the vertical direction of the inner panel 2, the first projecting portion 21 has a center point “a” and a vertex “b” of one regular hexagon of virtual regular hexagons in which the entire plate surface is configured in a lattice shape. The six second projecting portions 22 and the six intermediate planes 23 are alternately and regularly arranged so as to surround the periphery of the first projecting portion 21. Yes.

As shown in FIGS. 6 to 11, the first projecting portion 21 includes a first base projecting portion 211 projecting a predetermined amount from the bottom portion on the intermediate reference plane K <b> 3, and a slant angle less than that of the first base projecting portion 211. It has a two-stage 12-sided truncated pyramid shape with a first flat surface 215 at the top of the one extended protrusion 212. A side surface of the first base protrusion 211 is inclined by an inclination angle α _{1 with} respect to the intermediate reference plane K3, and a side surface of the first extension protrusion 212 is inclined by an inclination angle α _{2 with} respect to the intermediate reference plane K3. parts 211 and the first bent portion of the boundary between the first extended projection part 212 213 is disposed on the first reference plane K1 virtual arranged in parallel at intervals S ₁ between the intermediate reference plane K3. In this example, the inclination angle α ₁ = 45 °, α ₂ = 10 °, and the interval S ₁ = 6 mm. The protrusion height H ₁ of the first protrusion 21 from the intermediate reference plane K3 is 12 mm, and the ratio (H ₁ / t) to the plate thickness t (mm) before the formation of the concavo-convex portion is 13.3.

The second projecting portion 22 connects the second base projecting portion 221 projecting a predetermined amount from the bottom portion on the intermediate reference plane K3 and the second extending projecting portion 222 having a slanting angle smaller than that of the second base projecting portion 221, It has a two-stage hexagonal truncated pyramid shape with a second plane 225 at the top. The side surface of the second base protrusion 221 is inclined at an inclination angle β _{1 with} respect to the intermediate reference plane K3, and the side surface of the second extension protrusion 222 is inclined at an inclination angle β _{2 with} respect to the intermediate reference surface K3. parts 221 and the second bent portion of the boundary between the second extended projection part 222 223 is arranged on the second reference plane K2 virtual arranged in parallel with a gap S ₂ between the intermediate reference plane K3. In this example, the inclination angle β ₁ = 45 °, β ₂ = 15 °, and the interval S ₁ = 6 mm. The protrusion height H ₂ of the second protrusion 22 from the intermediate reference plane K3 is 12 mm, and the ratio (H ₂ / t) to the plate thickness t (mm) before the formation of the concavo-convex portion is 13.3.

In FIG. 10, only the 1st protrusion part 21 was extracted and the top view (a), the perspective view (b), and the front view (c) were shown. Similarly, in FIG. 11, only the 2nd protrusion part 22 was extracted and the top view (a), the perspective view (b), and the front view (c) were shown.
As shown in FIG. 10 (a), set outside dimension D ₁₁ of the base portion of the first basic protrusion 211 of the first protrusion 21 is 125 mm, external dimension D ₁₂ of the base portion of the first extended projection part 212 to 110mm did. Therefore, the ratio (D ₁₁ / t) to the plate thickness t (mm) is 138.9.
Further, as shown in FIG. 11A, the outer dimension D ₂₁ of the bottom portion of the second base protruding portion 221 in the second protruding portion 22 is 94 mm, and the outer dimension D ₂₂ of the bottom portion of the second extending protruding portion 222 is 80 mm. Set to. Therefore, the ratio (D ₂₁ / t) to the plate thickness t (mm) is 104.4. The outer dimensions D ₁₁ and D ₂₁ are the diameters of the circumscribed circles of the outer contours of the respective bottom portions.

Further, as shown in FIG. 10A, the dodecagonal first flat surface 215 at the apex of the first projecting portion 21 is set to 32% of the above D ₁₁ with the outer dimension D ₁₅ being 40 mm.
Further, as shown in FIG. 11A, the hexagonal second flat surface 225 at the apex of the second projecting portion 22 is set to 31.9% of the above D ₂₁ with its outer dimension D ₂₅ being 30 mm.

Further, as shown in FIG. 6, when viewed from the direction orthogonal to the intermediate reference plane K <b> 3, the center distance L ₁ between the second protrusion 22 and the intermediate plane 23 is 50 mm, and the first protrusion 21 and the second protrusion 22 The center-to-center distance L ₂ was 100 mm, and the center-to-center distance L ₃ between the first protrusion 21 and the intermediate plane 23 was 86.6 mm.

(FEM analysis)
FEM analysis was performed to quantitatively determine the rigidity improvement effect of the uneven portion 202 of this example.
The FEM analysis method assumes a cantilever with one end Z1 of the test piece consisting only of the uneven portion 202 of the size shown in FIG. 7 and the other end Z2 as a free end, and applies a load of 1 N to the free end. Rigidity is obtained from the amount of deflection when applied. The size of the test piece was 300 mm × 346 mm, and the plate thickness t before press forming the concavo-convex portion 202 was 0.9 mm, and after the forming, 0.8 mm.
The evaluation of the rigidity was performed based on the ratio of the bending amount obtained as a result of performing the same FEM analysis on the flat base plate before the formation of the concavo-convex part 202, and by how many times the rigidity was improved. As a result, it was found that the concavo-convex portion of this example was improved by 8.4 times in rigidity compared to the flat base plate.

(Example 3)
This example is an example having the inner panel 2 having the concavo-convex portion 203 in which the shapes of the first protrusion 21 and the second protrusion 22 in the second embodiment are changed. The inner panel 2 is made of a 5000 series aluminum alloy with a plate thickness t = 0.9 mm before the formation of the concavo-convex portion 203.
That is, as shown in FIGS. 12 to 15, the first projecting portion 21 includes a first base projecting portion 211 having a truncated pyramid shape and a first base projecting portion 211 projecting a predetermined amount from the bottom portion on the intermediate reference plane K <b> 3. The first extending protrusion 212 having a 12-pyramid shape whose inclination angle is gentler than that of the first extended protrusion portion 212 is connected, and a two-step 12-pyramidal shape having no flat surface is provided.

As shown in the drawing, the second protrusion 22 has a hexagonal truncated pyramid-shaped second base protrusion 221 that protrudes a predetermined amount from the base on the intermediate reference plane K3, and an inclination angle that is greater than that of the second base protrusion 221. A second hexagonal pyramid-shaped second extended protrusion 222 is connected, and has a two-stage hexagonal pyramid shape without a flat surface at the top. Further, as shown in FIG. 14, the projecting height of the first projecting portion 21 H ₁ (mm) and protruding height of the second protrusion 22 H ₂ (mm) are both set to 16 mm.
Others are the same as in the second embodiment. In addition, the vertex part of the 1st protrusion part 21 and the 2nd protrusion part 22 is a little roundish from the problem on shaping | molding.
Also in this case, substantially the same effect as that of the second embodiment can be obtained.

Example 4
As shown in FIGS. 16 and 17, the inner panel 2 having the concavo-convex portion 204 of the present example also includes a first protruding portion 21 that protrudes in one direction in the thickness direction, a second protruding portion 22 that protrudes in the other direction, and an intermediate therebetween And an intermediate plane 23 located at the center. The inner panel 2 is made of a 5000 series aluminum alloy plate with a plate thickness t = 0.9 mm before the formation of the concavo-convex portion 204.

  In the concavo-convex portion 204 of this example, as in the first embodiment, the first projecting portion has a one-stage 12-sided truncated pyramid shape, and the second projecting portion 22 has a one-step hexagonal truncated pyramid shape. On the other hand, unlike the first embodiment, the side surface of the first base protrusion 211 of the first protrusion 21 and the inclination angle of the second base protrusion 221 of the second protrusion 22 are different angles, and the boundary between the two is clear. The shape was changed to appear on the exterior.

Although illustration is omitted, when the dimensions of each part are indicated by the same reference numerals as in the first embodiment, the inclination angle α of the side surface of the 12-pyramidal frustum shape constituting the first basic protrusion 211 is 18 °, and the second basic protrusion The inclination angle β of the side surface of the hexagonal pyramid shape forming 221 was 25 °.
Also, external dimension D ₁₁ of the first projecting portion 21 was set to 125 mm. Therefore, the ratio (D ₁₁ / t) to the plate thickness t (mm) is 138.9. Also, external dimension D ₂₁ of the second projecting portion 22 was set to 94 mm. Therefore, the ratio (D ₂₁ / t) to the plate thickness t (mm) is 104.4.

The protrusion height H ₁ of the first protrusion 21 was 18 mm. Therefore, the ratio (H ₁ / t) is 20. The protrusion height H ₂ of the second protrusion 22 was 18 mm. Therefore, the ratio (H ₂ / t) is 20.
The center distance L ₁ between the second protrusion 22 and the intermediate plane 23 is 50 mm, the center distance L ₂ between the first protrusion 21 and the second protrusion 22 is 100 mm, and the distance between the first protrusion 21 and the intermediate plane 23 is 100 mm. The center distance L ₃ was 86.6 mm.

(FEM analysis)
In order to quantitatively determine the rigidity improvement effect of the uneven portion 204 of this example, FEM analysis was performed in the same manner as in Example 2. As a result, it was found that the concavo-convex portion of this example was improved in rigidity by 9.3 times compared to the case of the flat base plate.

  As shown in FIGS. 18 and 19, the first flat surface 215 is eliminated and the first projecting portion 21 is formed in a single 12-sided pyramid shape, and the second flat surface 225 is eliminated and the second projecting portion 22 is disposed in one step. The inner panel 2 having the concavo-convex portion 205 having a hexagonal pyramid shape can also be obtained. In this case, substantially the same effect as described above can be obtained.

DESCRIPTION OF SYMBOLS 1 Vehicle panel 2 Inner panel 20,202,203,204,205 Irregularity part 21 1st protrusion part 211 1st foundation protrusion part 212 2nd extension protrusion part 215 1st plane 22 2nd protrusion part 221 2nd foundation protrusion part 222 Second extension protrusion 225 Second plane 23 Intermediate plane

Claims (9)

In a vehicle panel having an outer panel made of an aluminum alloy plate and an inner panel made of an aluminum alloy plate arranged toward the back surface of the outer panel,
The inner panel has an uneven portion protruding in the thickness direction,
The concavo-convex portion is based on an intermediate reference plane that is a virtual plane,
A first protrusion having a 12 pyramid shape or a 12 pyramid shape having a base on the intermediate reference plane;
A second projecting portion having a base on the intermediate reference plane and projecting to the opposite side of the first projecting portion, or a hexagonal pyramid shape or a hexagonal pyramid shape;
An intermediate plane that is a quadrangular plane provided on the intermediate reference plane,
When viewed from the vertical direction of the intermediate reference plane, the first protrusion corresponds to the position of the center point of each substantially regular hexagon of the virtual substantially regular hexagons constituting the entire plate surface in a lattice shape and the positions of the vertices. The six second protrusions and the six intermediate planes are alternately and regularly arranged so as to surround the periphery of the one first protrusion.
The intermediate plane is distributed and arranged so as to connect the adjacent first protrusions, and the second protrusion is distributed and disposed at a position surrounded by the first protrusion and the intermediate plane. A vehicle panel characterized by that.   2. The vehicle panel according to claim 1, wherein at least one of the first projecting portion and the second projecting portion is a base projecting portion projecting a predetermined amount from a bottom portion on the intermediate reference plane, and an apex of the base projecting portion. A vehicle panel characterized by having a one-stage shape having a flat surface formed in a portion.   3. The vehicle panel according to claim 1, wherein at least one of the first projecting portion and the second projecting portion includes a base projecting portion projecting a predetermined amount from a bottom portion on the intermediate reference surface, and the base projecting portion. A vehicle panel characterized by having a multi-stage shape in which extended protrusions having different inclination angles are connected.   4. The vehicle panel according to claim 2, wherein the first projecting portion and the second projecting portion have the same inclination angle of the basic projecting portions of the both, and are connected at adjacent portions to form a plane. The vehicle panel characterized by being.   5. The vehicle panel according to claim 3, wherein an inclination angle of a side surface of the extended projecting portion with respect to the intermediate reference surface is in a range of 5 ° to 60 °.   The vehicle panel according to any one of claims 2 to 5, wherein an inclination angle of the basic protrusion with respect to the intermediate reference plane is in a range of 10 ° to 90 °.   The vehicle panel according to any one of claims 1 to 6, wherein the inner panel has a thickness t of 0.3 mm to 2.0 mm before formation of the uneven portion. The vehicle panel according to any one of claims 1 to 7, wherein a protrusion height H1 (mm) of the _first protrusion from the intermediate reference surface and a plate thickness t (mm) before the formation of the uneven portion. The ratio (H ₁ / t) is 1 ≦ H ₁ /t≦−2.5θ ₁ +227 in relation to the largest inclination angle θ ₁ (°) on the side surface of the first protrusion, The ratio (H ₂ / t) between the height H ₂ (mm) of the _second protrusion from the intermediate reference plane and the plate thickness t (mm) (H ₂ / t) is the largest inclination on the side surface of the second protrusion. A vehicle panel having a relationship of 1 ≦ H ₂ /t≦−2.5θ ₂ +227 in relation to an angle θ ₂ (°). The vehicle panel according to any one of claims 1 to 8, the ratio of the outer dimension D ₁₁ of the first protrusion (mm) and the concavo-convex part forming front plate thickness _{t (mm) (D 11 /} t ) Is 10 to 500, and the ratio (D ₂₁ / t) of the outer dimension D ₂₁ (mm) of the bottom portion of the second protrusion to the plate thickness t (mm) is 10 to 500. Vehicle panel.

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