JP3120656B2 - Car hood structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hood structure for an automobile, and more particularly to a structure for reducing the impact of a head impactor from the hood.

[0002]

2. Description of the Related Art A conventional hood structure of an automobile of this type is shown in FIGS. 13 to 16 (see Japanese Utility Model Application Laid-Open No. 61-26882). 13 is a perspective view showing a conventional automobile having a hood structure, FIG. 14 is an enlarged view of a main part of FIG. 13, and FIG.
FIG. 5 is a sectional view taken along line V-V of FIG.

As shown in FIG. 13, a hood inner panel 7 is provided below the hood outer panel 3 of the hood 1 (on the engine room 5 side). The hood inner panel 7 has a frame 9 and an inner rib 11 located inside the frame 9 and reinforcing the frame 9. Both sides of the frame 9 at the rear of the vehicle body are rotatably supported by the vehicle body via hood hinges 13. An engine 15 is disposed in the engine room 5, and a flat plate portion 17 is provided between the inner ribs 11 located above the vehicle body of the engine 15 as shown in FIG. The flat plate portion 17 is provided with a plurality of cut-and-raised pieces 19 cut and raised to face the engine 15. As shown in FIG. 15, each cut-and-raised piece 19 is formed in a substantially arc-shaped cross section, and both ends 21 are continuous with the flat plate portion 17.

According to such a hood structure, when the pedestrian's head hits the outer surface of the hood outer panel 3, the hood outer panel 3 and the inner rib 11 are deformed so as to protrude toward the engine room 5, and the cut-and-raised piece 19 is further bent. And is crushed and deformed. That is,
The amount of energy absorbed by the hood 1 above the vehicle body of the engine 15 is increased by cutting and raising the piece 19 to reduce the moving distance of the hood 1 to secure the required amount of energy absorption.

[0005]

However, even if the amount of energy absorbed by the hood 1 is secured in this way, the hood 1
Is not always mitigated.

[0006] Experimental data relating to head impact resistance include a WSTC (Wayne State Tolerace Curve) shown in FIG.
ve) is known ("Automobile Engineering Handbook <Part 3>" issued by the Japan Society of Automotive Engineers of Japan (September 3, 1983)
(0st edition, first edition), page 2-30, and "Automotive Engineering, Vol. 16, Automobile Safety", published by Sankaido Co., Ltd. (March 20, 1980, first edition, page 201-203).

The effective acceleration used as a parameter of the WSTC is the average acceleration (the integral value of the acceleration waveform divided by the operation time), and corresponds to the average reaction force applied to the head in the event of a collision. .

According to the WSTC, even if the average reaction force received by the head impactor is small to some extent (effective acceleration = G1
), If the duration becomes longer (duration> T1), the danger area is reached, and conversely, even if the average reaction force is large (effective acceleration =
G2), if the duration is extremely short (duration <T2), it does not reach the danger zone and belongs to the safety zone.

That is, head impact resistance is determined by both factors of acceleration and action time. If the amount of energy absorption is large, head impact resistance is not necessarily lowered, and the initial reaction force at impact is reduced. In some cases, a sudden rise to some extent within a predetermined period of time may lower the head impact value than maintain a not so high reaction force for a long time.

Further, WSTC is experimental data under linear acceleration, and the actual impact received when the head impactor (head impactor) collides with the hood 1 shows not a linear acceleration but a complicated acceleration waveform. WST on actual impact
C cannot be applied directly. For this reason, HIC, which is one of the failure reference values, is used as a method for evaluating safety based on the WSTC based on the results of impact experiments using an impactor.
A method using a value (Head Injury Criterion) is known.

The HIC value is calculated by the following equation.

(Equation 1)

(Equation 2) Is calculated according to T1 and t2 in both equations are 0 <t1 <
t2 is an arbitrary time during the acceleration action, and a (t) is the acceleration at the center of gravity of the head of the impactor. As for the HIC value, the smaller the value is, the higher the security is. Generally, HIC = 1000
Is considered a safety limit.

According to the equation, HIC values, the average acceleration a ₁₂ at the working time from any t1 to t2 2.5
It is calculated as the maximum value of the value obtained by multiplying the power value by the operation time (t2-t1). That, HIC value in principle if the impact behavior (acceleration waveform) differences also differ, an average acceleration a ₁₂ and its action time (t2 -t1) is a factor that determines the magnitude of the HIC value. The relationship between the average acceleration a ₁₂ and its action time (t2 -t1) can be replaced with the relationship of the reaction force and the movement distance of the hood 1 of the hood 1, the reaction force of the hood 1 and also by the movement distance , HIC values are determined.

[0013] As a result, the fact that the amount of impact energy absorbed is large does not mean that the HIC value is uniformly reduced, but there are many cases where the HIC value differs even if the energy absorption amount is the same. Further, even if the HIC value at a certain point of the hood 1 becomes a low value, the HIC value may show a high value at another point outside the one point.

Therefore, as shown in FIG. 13, in the conventional hood structure, since the cut-and-raised piece 19 is formed in a substantially arc-shaped cross section, the rise of the crush reaction force of the cut-and-raised piece 19 is delayed.
There is a risk that a relatively high reaction force may be maintained until after a long time has elapsed, and in order to reduce head impact, it was necessary to reduce the crush reaction force of the cut-and-raised piece 19 and increase the stroke. .

Therefore, the present invention is to reduce the moving distance of the hood to ensure sufficient energy absorption,
It is an object of the present invention to provide a hood structure capable of efficiently lowering the C value and reducing head impact.

[0016]

According to the first aspect of the present invention,
A hood structure of an automobile that includes a hood outer panel that closes an upper surface of an engine room in which strut towers are disposed on both sides of a vehicle width and absorbs an impact on the hood outer panel, wherein the strut tower and the hood outer panel have a structure. a cavity is provided, on at least a portion of said cavity has a straight outer support part, together with fills the gaps in the vehicle height direction between the upper and the hood outer panel of the strut tower, the hood outer panel is the shock
When it is deformed by receiving it, the hood outer panel is immediately
A shock absorber is provided which is supported and arranged to suppress the deformation .

According to a second aspect of the present invention, there is provided the hood structure of the automobile according to the first aspect, wherein the shock absorber is provided on the hood outer panel, and is provided near the upper part of the strut tower; A shock absorbing member provided in a cavity between the hood outer panel and the hood inner panel, wherein the shock absorbing member has an upper connecting portion connected to the hood outer panel side and a lower side connected to the hood inner panel side; A connection portion, and the outer support portion is a straight leg connecting the upper connection portion and the lower connection portion.

According to a third aspect of the present invention, there is provided the hood structure for an automobile according to the second aspect, wherein the shock absorbing member is integrally provided upright from the hood inner panel.

According to a fourth aspect of the present invention, there is provided the hood structure for an automobile according to the first aspect, wherein the shock absorber is provided on the strut tower side.

According to a fifth aspect of the present invention, there is provided the hood structure for an automobile according to the first to fourth aspects, wherein the shock absorber is provided at an outer end of the vehicle width and the hood is closed when the hood outer panel is closed. An outer panel is provided with an outer break prevention member for supporting the outer end of the outer panel in the vehicle width.

[0021]

According to the first aspect of the present invention, when the hood receives an impact, the linear outer support portion is immediately brought into contact with the outer panel at the time of local deformation of the hood outer panel accompanying the movement of the hood and thereafter at the initial stage of sinking deformation. , The deformation of the hood outer panel is suppressed, and a sufficient initial reaction force can be obtained from a state in which the movement distance of the hood is short. Also, when the movement distance of the hood increases, the reaction force decreases due to the inertial force of the hood outer panel. A secondary reaction force of a desired magnitude is generated, and the reduction of the reaction force is appropriately mitigated.
As a result, the relationship between the reaction force of the hood and the movement distance thereof can be made an ideal state, and the movement distance of the hood can be kept small to ensure sufficient energy absorption, and the HIC value can be reduced efficiently. In addition, the impact on the head can be reduced.

According to the second aspect of the present invention, in addition to the function of the first aspect, since the impact force is also distributed to the hood inner panel via the straight leg portion, the deformation of the hood outer panel is more strongly suppressed, and the hood outer panel is more firmly suppressed. A large initial reaction force can be obtained from a state in which the moving distance is small. Further, since the impact force is dispersed to the hood inner panel even when the hood outer panel sinks, an accurate initial reaction force can be obtained without a risk that the rate of reduction of the reaction force is extremely reduced.

According to the third aspect of the present invention, in addition to the function of the second aspect, since the shock absorber is provided integrally with the hood inner panel, the number of parts, the weight of the hood, and the assembling workability are reduced. Improvement can be achieved.

According to the fourth aspect of the invention, in addition to the function of the first aspect, since the shock absorber is provided on the strut tower side, the weight of the hood can be reduced, and the openability of the hood can be maintained well. .

According to the fifth aspect of the present invention, in addition to the functions of the first to fourth aspects, the shock absorber is provided with an outer fold prevention member, so that the hood outer panel can be prevented from being broken at the vehicle width end. And the initial reaction force of the hood can be reliably increased.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention has a structure in which the HIC value is efficiently reduced above the vehicle body of a strut tower 51 in which the movement distance of a hood 31 is greatly limited as shown in FIG. It is intended to reduce the part impact property.

Specifically, the moving distance of the hood 31 and H
A waveform (ideal waveform) indicating an ideal relationship between the reaction force of the hood 31 and the amount of movement thereof, which can suppress both the IC values, is calculated by calculating the energy absorption amount required at the time of impact and the derivation formula (1). Based on (2), it is obtained in advance by calculation, and an impact experiment is performed on the hood 31 above the strut tower 51 to obtain a waveform (basic waveform) of the actual reaction force.
By adopting a hood structure in which the basic waveform approaches the ideal waveform, the HIC value is efficiently and reliably reduced with a short moving distance.

Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing a hood structure of an automobile according to a first embodiment, FIG. 2 is a sectional view taken along line HH of the hood of FIG. 1, FIG. 3 is a plan view of a main part of FIG. 3 is a sectional view taken along the line II of FIG. 3, FIG. 5 is a sectional view taken along the line JJ of FIG. 3, and FIG. 6 shows a hood structure (foundation structure) as a basis of the present embodiment in the same section as FIG. .

As shown in FIGS. 1 and 2, a hood outer panel 33 of the hood 31 closes an upper surface of an engine room 35, and a hood inner panel 37 is provided below the hood outer panel 33 (on the side of the engine room 35). Have been. The hood inner panel 37 has a plurality of inner ribs 39 having a hat-shaped cross section, which are disposed on the peripheral portion and inside of the hood outer panel 33 and increase the rigidity of the hood outer panel 37.

Strut towers 51 are provided on both sides of the engine room 35 in the vehicle width. Strut tower 5
1 is provided so as to project from the hood ridge 49 to the inside of the vehicle width, and an upper surface 5 as an upper portion of the strut tower 51 is provided.
Three bolts 52 are erected on 1a, and a nut 53 is fastened to each bolt 52. In the figure, 32 indicates a fender.

A hollow portion A is provided between the strut tower 51 and the hood outer panel 33, and a flat plate portion 41 is provided on the hood inner panel 37a above the vehicle body of the strut tower 51. The flat plate portion 41 is located inside the vehicle width and
The hood inner panel 37a is extended from the inner ribs 39 so as to be continuous with the inner ribs 39 on the outside of the vehicle width.
Is provided near the bolt 52 and the nut 53 as an upper part of the strut tower 51 . Vehicle width inner end 45a of vehicle width inner inner rib 39a continuous with flat plate portion 41
Is bonded to the hood outer panel 33 by an elastic resin 46 such as mastic, and the vehicle width outer end 45b of the vehicle width outer inner rib 39b is attached to the hood outer panel 3
3 is crimped to the peripheral edge 33a by folding the peripheral edge 33a.

A plurality of impact absorbing members 55, 57, and 59 are provided in a hollow portion A between the hood inner panel 37a and the hood outer panel 33 which is close to the bolt 52 and the nut 53. The hood inner panel 37a and the shock absorbing members 55, 57, 59 constitute a shock absorber, and the shock absorbing members 55, 57, 59 have two (55) in the middle and one on the inside and outside of the vehicle width. It is provided at four places such as (57, 59) one by one. Intermediate portion shock absorbing member 55
And the impact absorbing member 57 on the inner side of the vehicle width includes three bolts 5
2. It is provided above the nut 53 so as to correspond to the nut 53.

As shown in FIG. 4, the shock absorbing member 59 constituting the shock absorber on the outer side of the vehicle is formed in a hat shape having a rectangular or trapezoidal cross section, and is bonded to the hood outer panel 33 via the resin 46. A connecting portion 59a, a straight leg portion 59b as an outer support portion which is bent downward from both ends of the upper connecting portion 59a and extends linearly, and a straight leg portion 5;
9b is provided with a lower connecting portion 59c bent from the lower end and welded to the hood inner panel 37a.

The hood inner panel 37a, which is located below the shock absorbing member 59, is provided with a bumper rubber mounting member 60 constituting a shock absorber.
From below to the vehicle body in a hat shape with a rectangular or trapezoidal cross section. The bump rubber attachment member 60 includes a leg portion 60b as an outer support portion linearly extending below the vehicle body from the hood inner panel 37a, and a bump rubber fitting portion 60a provided between the leg portions 60b. A hole 60d is formed in the bump rubber fitting portion 60a, and a bump rubber 47 made of an elastic resin as an outer break prevention member abutting on the upper surface 51a of the strut tower 51 is fitted into the hole 60d. That is, bumper bar 4
7 contacts the upper surface 51 a of the strut tower 51, so that the outer end of the vehicle width of the hood outer panel 33 is supported when the hood outer panel 33 is closed.

As shown in FIG. 5, the shock absorbing member 55 in the middle portion
Are provided opposite to bolts 52 and nuts 53 projecting from the upper surface 51a of the strut tower 51, and like the shock absorber 59 on the outer side of the vehicle width, the upper connecting portion 55a , the straight leg portion 55b, and the lower connecting portion 55c. In addition, the shock absorber 57 on the inner side of the vehicle width is
This is almost the same configuration.

The impact absorbing members 55,
57 are connected to the hood outer panel 33 and the hood inner panel 37a at both ends, and the hood inner panel 37a is provided near the bolts 52 and nuts 53 of the strut tower 51. The gap between the strut tower 51 and the hood outer panel 33 in the vehicle height direction is filled with the straight legs 55b and 57b and the hood inner panel 37a.

The straight leg portion 59b of the shock absorbing member 59 on the outer side of the vehicle is connected at both ends to the hood outer panel 33 and the hood inner panel 37a.
a is a bumper bar mounting portion 6 having a bumper bar 47;
Since the zero leg 60b is erected, the gap between the strut tower 51 and the hood outer panel 33 in this position in the vehicle body height direction is the straight leg 59b, the hood inner panel 37a, and the leg 60b. Will be buried.

Next, the operation will be described.

The hood 31 configured as described above has a waveform similar to an ideal waveform (reaction force (F) of the hood-moving distance due to deformation of the hood) that can effectively reduce the HIC value in an impact test. Is obtained.

FIG. 6 shows a basic structure on which an impact test was performed.
FIG. 7 shows a basic waveform C1 and an ideal waveform Cm obtained as a result of the shock experiment.

A hood 63 having a basic structure as shown in FIG. 6 has substantially the same configuration as that of FIG. 1 except that no shock absorber is provided, and a bolt 52 and a nut 53 are opposed to the hood outer panel 33. I have.

In the impact test on the foundation structure, the hood outer panel 3 opposed to the bolts 52 and nuts 53 at the intermediate portion was used.
This is performed by placing the impactor 61 on the upper side of 3 and measuring the moving distance and acceleration of the impactor 61. The moving distance and acceleration of the impactor 61 correspond to the moving distance S (moving distance of the hood outer panel 33) due to the deformation of the hood shown on the horizontal axis in FIG. 7 and the reaction force F of the hood 63 shown on the vertical axis in FIG. Then, the basic waveform C1 shown in FIG. 7 is obtained by the above experiment. In the figure, the basic waveform C1 has a schematic shape.

The ideal waveform Cm is an ideal reaction force waveform that can suppress both the amount of movement of the hood and the HIC value in the basic structure. It is obtained by calculation based on the above. The internal area defined by the ideal waveform Cm and the moving distance S on the horizontal axis in the drawing is the absorbed energy, and this internal area is set to be the required amount of energy absorption. The energy absorption required at the time of impact is obtained by an impact experiment, calculation, or the like.

In the ideal waveform Cm, the initial reaction force suddenly increases in the initial stage of deformation where the moving distance S is small, reaches the maximum reaction force F1 at the moving distance S1 (p _{m in the} figure), and becomes the reaction force during the moving distance S2. F but decreases suddenly to F2, the deformation late after moving distance S2, shoulder the ratio of the reaction force decrease acts secondary reaction force is relaxed (figure q _m) is manifested, further movement distance At S3, the reaction force F suddenly decreases again, and the moving distance S0
The impact energy is completely absorbed and the reaction force reaches almost zero.

In the basic waveform C 1, in the initial stage of the deformation immediately after the collision, the hood outer panel 33 locally deforms along the outer shape of the impactor 61, and the initial reaction force mainly depending on the tension of the hood outer panel 33 increases. However, at the end of the hood outer panel 33, the hood outer panel 33
Are easily broken and deformed, and sufficient tension cannot be obtained immediately.
For this reason, the rate of increase of the initial reaction force is smaller than that of the ideal waveform Cm, and the maximum reaction force (approximately F3) obtained is also smaller than the ideal waveform Cm.
Is lower than the maximum reaction force F1. (P _{1 in the} figure). After obtaining the maximum reaction force F3, the hood outer panel 33 starts to sink over a wide range due to the inertial force received from the impactor 61, and the reaction force F decreases rapidly with an increase in the moving distance S. However, the reaction force is further reduced than F2. Then, when the inner rib 39 is crushed and deformed and the hood outer panel 33 interferes with the bolt 52 and the nut 53, the reaction force increases again to F4, and the movement of the hood 63 stops.

As described above, in the hood 63 having the basic structure,
Since the initial reaction force is small and the reaction force F increases again after the movement distance increases, the shoulder portion (q in the figure)
_m ) cannot be obtained. For this reason, the reaction force F may increase after a long time has elapsed from the start of the impact, which may adversely affect the head impact. Further, when the hood outer panel 33 stops by interfering with the bolts 52 and the nuts 53, the energy absorption may be insufficient.

On the other hand, the hood 31 according to the present embodiment
In the initial stage of deformation, first, the hood outer panel 33 locally deforms along the outer shape of the impactor 61, and the initial reaction force rises and rapidly increases. At this time, the straight leg portion 55b of the intermediate shock absorbing member 55 fills the gap between the bolt 52 / nut 53 and the hood outer panel 33 in the height direction of the vehicle body.
Immediately supported by 5b. Therefore, the deformation of the hood outer panel 33 is suppressed, and a sufficient initial reaction force can be obtained from a state where the moving distance of the hood 31 is short, and the moving distance S
Is approximately S1 , a maximum reaction force (substantially F1) is obtained. In addition, the bumper bar 47 is connected to the hood outer panel 33.
Is prevented from breaking at the outer end of the vehicle width, so that the initial reaction force surely increases.

After obtaining the maximum reaction force, the hood outer panel 33 starts sinking in a wide range due to the inertial force received from the impactor 61, and the reaction force F decreases rapidly. The outer panel 33 is a straight leg 55
b, and the impact force on the hood outer panel 33 is applied to the hood inner panel 3 by the linear leg 55b.
7a, the reaction force F does not extremely decrease,
The reduction ratio of the reaction force F can be set to a desired ratio. Then, when the moving distance S reaches approximately S2 , the reaction force F decreases to approximately F2, and then the straight leg 55b starts crushing deformation (plastic deformation), and a desired secondary reaction force is generated and an accurate shoulder is generated. The part appears. When the straight leg 55b is sufficiently crushed, the impact energy is completely absorbed before the hood outer panel 33 directly interferes with the bolt 52 / nut 53, and the reaction force F
Again sharply decreases to almost zero, and the hood 31 stops as shown in FIG.

Similar functions and effects can be obtained for the hood outer panel 33 above the shock absorbing members 57 and 59 on the inside and outside of the vehicle width.

Therefore, according to the present embodiment, a waveform similar to the ideal waveform Cm can be obtained, and the HIC can be obtained with a short moving distance.
The value can be effectively reduced to reduce head impact.

FIGS. 9 and 10 show a first embodiment of the present invention.
FIG. 9 is a plan view corresponding to FIG. 3 and FIG. 10 is a sectional view taken along the line KK of FIG. 9 corresponding to FIG.

The shock absorbing member 65 corresponds to the shock absorbing member 55 at the intermediate portion, and
7a, the shock absorbing member 65 is substantially the same as the shock absorbing member 55 except that the shock absorbing member 65 is integrally erected on the hood inner panel 37a. And a lower connection portion 65c bent from the inner panel 37a.

According to such a modified example, in addition to the effect of the shock absorbing member 55, the shock absorbing member 65 is integrally erected from the hood inner panel 37a, so that the number of parts is reduced and the assembling workability is reduced. Improvement can be achieved.

Next, a second embodiment according to the fourth and fifth aspects of the present invention will be described with reference to FIGS.

FIG. 11 is a sectional view of a main part of the second embodiment.
FIG. 12 is a perspective view of a main part of the second embodiment.

As shown in FIG. 11 and FIG.
The strut tower 51 is provided with a shock absorber 71 on the upper surface 51a, and the same portions as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

The shock absorber 71 is a hood outer panel 3
3 and a plurality of outer support portions, which are bent downward from the periphery of the upper plate portion 81 toward the vehicle body and extend linearly from the hood outer panel 33 side to the strut tower 51 side. Straight legs 73, 75, 77 are provided. The upper plate portion 81 is provided on the upper surface 5 of the strut tower 51.
The upper plate portion 81 is provided so as to cover the upper portions of the three bolts 52 and nuts 53 protruding from the shock absorber 7.
A hole 79 for setting the crush reaction force to a desired size
Are formed. The hole 79 is preferentially arranged above the bolt 52 and the nut 53, and is used when the bolt 52 is fastened.
Improves workability . The lower ends 82, 83 of the straight legs 73, 75 near the bolts 52, nuts 53 are bent toward the bolts 52, nuts 53, and the lower ends 82, 8 are formed.
3 are jointly fastened to the bolt 52 and the nut 53, so that the shock absorber 71 is attached to the upper surface 51 of the strut tower 51.
a.

A bumper bar 67 made of an elastic resin is provided outside the vehicle width of the upper plate portion 81 as an outer break prevention member for supporting and supporting the outer end of the vehicle width of the hood outer panel 33 when the hood outer panel 33 is closed. .

According to this embodiment, the same operation and effect as those of the first embodiment can be obtained.

That is, in the initial stage of deformation, the hood outer panel 33 first undergoes local deformation, and the initial reaction force rises and rapidly increases. At this time, the outer panel 33 is
3, 75, 77, the deformation of the hood outer panel 33 is suppressed, and a sufficient initial reaction force is obtained from a state where the moving distance is short, and the maximum reaction force is obtained when the moving distance S is approximately S1. (Substantially F1) is obtained. In addition, since the bumper bar 67 prevents the hood outer panel 33 from breaking at the vehicle width end, the initial reaction force surely increases.

After obtaining the maximum reaction force, the hood outer panel 33 starts sinking in a wide range due to the inertial force, and the reaction force F suddenly decreases. When the hood outer panel 33 decreases, the impact force on the hood outer panel 33 becomes linear. Since it is still supported by the legs 73, 75, 77, no extreme reduction of the reaction force F occurs, and the reduction ratio of the reaction force F is maintained at a desired ratio. When the moving distance S reaches approximately S2, the reaction force F decreases to approximately F2. Thereafter, the linear legs 73, 75, and 77 start crushing deformation (plastic deformation), and a desired secondary reaction force is generated. A precise shoulder appears. When the straight legs 73, 75, 77 are sufficiently crushed, the hood outer panel 33 is
The impact energy is completely absorbed before directly interfering with the nut 53, and the reaction force F sharply decreases again to almost zero.

Therefore, according to the present embodiment, a waveform similar to the ideal waveform Cm can be obtained, and the HIC can be obtained with a short moving distance.
The value can be effectively reduced to reduce head impact.

Further, since the shock absorber 71 is provided on the strut tower 51 side, the weight of the hood 70 is reduced, and the openability of the hood 70 can be maintained well.

Furthermore, since the shock absorber 71 is fixed to the strut tower 51 by being fastened together with the existing bolts 52 and nuts 53, the structure can be simplified.

[0066]

As described above, according to the first aspect of the present invention, the linear outer supporting portion immediately supports the outer panel after the impact on the hood, so that the moving distance of the hood is small. Provides a sufficient initial reaction force. Also, when the moving distance of the hood increases and reaches a predetermined distance, the shock absorber is crushed and deformed due to interference with the upper part of the strut tower, and a secondary reaction force of a desired magnitude is generated, and the reduction of the reaction force is accurately performed. Be relaxed. As a result, the relationship between the reaction force of the hood and the movement distance can be made an ideal state,
The moving distance of the hood can be kept small to secure sufficient energy absorption, and the HIC value can be efficiently reduced to reduce head impact.

According to the second aspect of the present invention, in addition to the effect of the first aspect, since the impact force is dispersed to the hood inner panel via the straight leg of the impact absorbing member, the initial reaction force can be accurately reduced. The head impact can be further reduced.

According to the third aspect of the invention, in addition to the effect of the second aspect, since the shock absorbing member is integrally provided upright from the hood inner panel, the number of parts, the weight of the hood, and the assembling work are reduced. Performance can be improved.

According to the fourth aspect of the invention, in addition to the effect of the first aspect, since the shock absorber is provided on the strut tower side, the weight of the hood is reduced, and the hood can be opened and closed well. Can be.

According to the invention of claim 5, claims 1 to 1
In addition to the effect of claim 4, the outer fold prevention member prevents the hood outer panel from breaking at the vehicle width end, so that the initial reaction force of the hood can be reliably and immediately increased,
Head impact can be reduced more reliably.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a hood structure of an automobile according to a first embodiment.

FIG. 2 is an HH sectional view of the hood of FIG.

FIG. 3 is a plan view of a main part of FIG. 1;

FIG. 4 is a sectional view taken along line II of FIG. 3;

FIG. 5 is a sectional view taken along the line JJ of FIG. 3;

FIG. 6 is a sectional view showing a basic structure of the first embodiment.

FIG. 7 is a schematic diagram showing a basic waveform C1 and an ideal waveform Cm.

FIG. 8 is a sectional view for explaining the operation of the first embodiment.

FIG. 9 is a plan view corresponding to FIG. 3 and showing a modification of the first embodiment.

FIG. 10 is a sectional view taken along the line KK of FIG. 9;

FIG. 11 is a sectional view of a main part of the second embodiment.

FIG. 12 is a perspective view of a main part of a second embodiment.

FIG. 13 is a perspective view showing an automobile having a conventional hood structure.

FIG. 14 is an enlarged view of a main part of FIG. 17;

FIG. 15 is a sectional view taken along line VV of FIG. 18;

FIG. 16 is a diagram showing a WSTC.

[Explanation of symbols]

31 Hood 33 Hood Outer Panel 35 Engine Room 37 Hood Inner Panel 37a Hood Inner Panel Above Strut Tower (Shock Absorber) 47 Bump Bar (Outer Break Prevention Member) 51 Strut Tower 55 Shock Absorber (Shock Absorber) 55a Upper Connection 55b Straight leg portion (outer support portion) 55c Lower connection portion 57 Shock absorbing member (shock absorber) 57a Upper connection portion 57b Straight leg portion (outer support portion) 57c Lower connection portion 59 Shock absorbing member (shock absorber) 59a Upper connection portion 59b Straight leg portion (outer support portion) 59c Lower connection portion 60 Bump rubber attachment portion (shock absorber) 60b Leg portion (outer support portion) 65 Shock absorbing member (shock absorber) 65a Upper connection portion 65b leg portion (Outer support part) 65c Lower connection part 67 Bump rubber Outer bending prevention member) 71 shock absorber 73 straight leg (outer supporting portion) 75 straight leg (outer supporting portion) 77 straight leg (outer supporting portion) A cavity

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B62D 25/10

Claims (5)

(57) [Claims] 1. A hood structure for an automobile, comprising: a hood outer panel for closing an upper surface of an engine room in which strut towers are disposed on both sides of a vehicle, and absorbing a shock to the hood outer panel. A hollow portion is provided between the hood outer panels, and at least a part of the hollow portion has a linear outer support portion, and fills a gap in the vehicle body height direction between the upper portion of the strut tower and the hood outer panel ,
When the hood outer panel is deformed by impact
Immediately support the hood outer panel to suppress the deformation
A hood structure for an automobile, comprising a shock absorber arranged as described above . 2. The hood structure of an automobile according to claim 1, wherein the shock absorber is provided on the hood outer panel, and is located near an upper portion of the strut tower; and the hood outer panel and the hood inner panel are provided. A shock absorbing member provided in a hollow portion between the hood, and the shock absorbing member has an upper connecting portion connected to the hood outer panel side and a lower connecting portion connected to the hood inner panel side. The hood structure of an automobile, wherein the outer support portion is a straight leg connecting the upper connection portion and the lower connection portion. 3. The hood structure of an automobile according to claim 2, wherein said shock absorbing member is integrally erected from said hood inner panel. 4. The hood structure of an automobile according to claim 1, wherein the shock absorber is provided on the strut tower side. 5. The vehicle hood structure according to claim 1, wherein the shock absorber is provided at an outer end of the vehicle width, and the outer end of the hood outer panel is closed when the hood outer panel is closed. A hood structure for an automobile, comprising an outer fold prevention member for supporting the hood.