JPWO2012096244A1 - Car front hood structure - Google Patents

Abstract

The shock absorbing part (29) of the front hood (15) of the automobile is curved upward and convexly by connecting the left and right side wall parts (29a) extending in the front-rear direction and the upper parts of the left and right side wall parts (29a). A wall portion (29b), and the upper wall portion (29b) is a plurality of surfaces (A, B, C, D) continuous in the front-rear direction via a plurality of ridgelines (d, e, f) extending in the left-right direction. The upper wall portion (29b) has a projecting height upward from the frame main body portion (28) and is higher on the rear side than the front side of the shock absorbing portion (29). The amount of energy absorption can be increased by sufficiently securing the crushing margin, and the deformation of the upper wall portion (29b) can be promoted by using the ridgeline (d, e, f) as a broken line, as well as the collision load. The upper wall (29b) is effectively deformed when is input from the front upper side It can be.

Description

  According to the present invention, the rear end of the front hood formed by connecting a hood skin to the upper surface of the hood frame is pivotally supported on the vehicle body via a hinge so as to be able to swing up and down. The present invention relates to a front hood structure of an automobile in which a provided striker is locked to a hood lock provided on a vehicle body.

  A front hood of an automobile includes an outer panel 11, an inner panel 12 coupled to the lower surface of the outer panel 11, and a hood lock reinforcement 13 disposed in a front portion of a space sandwiched between the outer panel 11 and the inner panel 12. And an auxiliary reinforcement 14 disposed in a space sandwiched between the outer panel 11 and the hood lock reinforcement 13, and the front end of the hood lock reinforcement 13 is disposed at a predetermined distance behind the front end of the front hood. In addition, Patent Document 1 below discloses that the auxiliary reinforcement 14 is disposed so as to extend from the front end of the front hood to the vicinity of the rear end of the hood lock reinforcement 13.

  According to this front hood, the outer panel 11 and the inner panel 12 ahead of the front end of the hood lock reinforcement 13 can be crushed together with the auxiliary reinforcement 14 and absorb the collision energy at the time of a frontal collision of the automobile.

  In addition, a reinforce 4 having a triangular cross section is arranged in the front space of the front hood of the automobile in which the outer panel 1 and the inner panel 2 are joined, and the fixing part 3 at the rear end of the reinforce 4 is fixed to the inner panel 2. The second bent portion 44 at the front end is locked to the locking portion 21 of the inner panel 2 and the first bent portion 41 at the center is protruded upward toward the lower surface of the outer panel 1. Is known.

According to this front hood, when a collision load is applied from the front, the second bent portion 44 is disengaged from the locking portion 21 and the reinforcement 4 is buckled in the front-rear direction to absorb the collision energy, and the collision load is applied from above. The first bent portion 41 is pushed downward by the lower surface of the outer panel 1 and the reinforcement 4 is buckled in the vertical direction, so that the collision energy can be absorbed.
Japanese Unexamined Patent Publication No. 2006-44544 Japanese Unexamined Patent Publication No. 2001-278120

  However, the device described in Patent Document 1 has a problem that the auxiliary reinforcement 14 is not considered for effectively absorbing the collision energy when the collision load is input from above.

  In addition, in the above-described Patent Document 2, when a strong collision load is input from above, the second bent portion 44 of the reinforcement 4 is disengaged from the engaging portion 21 of the inner panel 2, and the reinforcement 4 is There was a possibility that the collision energy could not be absorbed effectively by buckling up and down easily.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a front hood structure that can effectively absorb collision energy against a collision from the front or the upper side.

  In order to achieve the above object, according to the present invention, the rear end of a front hood configured by connecting a hood skin to the upper surface of the hood frame is pivotally supported on the vehicle body via a hinge so as to be vertically swingable. In a front hood structure of an automobile in which a striker provided at a rear position at a predetermined distance from the front end of a front hood is engaged with a hood lock provided on a vehicle body, the hood frame has a substantially flat frame body in the front part of the front of the striker. And a shock absorbing portion having a box structure projecting upward from the frame main body portion toward the lower surface of the hood skin, wherein the shock absorbing portion includes left and right side walls extending in the front-rear direction, and the left and right side walls. And an upper wall portion that is convexly curved upward and is connected in the front-rear direction via a plurality of ridge lines extending in the left-right direction. The first feature of the present invention is that the height of the upper wall projecting upward from the frame body is higher on the rear side than on the front side of the shock absorber. A front hood structure is proposed.

  According to the invention, in addition to the first configuration, the number of the ridge lines of the upper wall portion is larger on the rear side than on the front side of the shock absorbing portion. A front hood structure is proposed.

  According to the present invention, in addition to the first or second configuration, the impact absorbing portion is formed with a weakened portion that locally reduces its strength. A front hood structure is proposed.

  According to the invention, in addition to any one of the first to third configurations, the front hood includes a plurality of the shock absorbing portions juxtaposed in the left-right direction. A front hood structure is proposed.

  According to the present invention, in addition to the third configuration, a vehicle front hood structure is proposed in which the weakened portion is formed on the ridgeline.

  According to the invention, in addition to any one of the first to fourth configurations, the bracket for fixing the striker to the hood frame includes a front bracket made of a thin plate that supports the front side of the striker, It consists of a rear bracket made of a thick plate that supports the rear side of the striker, and the front bracket includes a rear connection portion connected to the striker, and a vertical wall portion rising upward from the rear connection portion via a broken line. And a front connection portion that extends forward from the upper portion of the vertical wall portion and is connected to the hood frame, and a plurality of the rear brackets are provided between the connection portion with the striker and the connection portion with the hood frame. A front hood structure for an automobile is proposed, which has a sixth characteristic line.

  According to the invention, in addition to the sixth configuration, the hood frame has a plurality of broken lines between a connection portion with the rear bracket and a connection portion with the front bracket. An automobile front hood structure is proposed.

  According to the present invention, in addition to the sixth or seventh configuration, an eighth feature is that the reinforcing member fixed to the front connection portion is opposed to the front surface of the vertical wall portion so as to be in contact therewith. An automobile front hood structure is proposed.

  According to the invention, in addition to any one of the first to fourth configurations, the impact absorbing portion protrudes upward from the front and rear portions of the frame main body toward the lower surface of the hood skin. A vehicle front hood structure having the ninth feature is proposed.

  According to the invention, in addition to the ninth configuration, the front shock absorbing portion on the front portion side of the hood frame is bent upward and convex on all ridge lines, and the rear shock absorbing portion on the rear portion side of the hood frame. A front hood structure for an automobile is proposed in which the portion is bent upward and convex at the ridge line excluding the rearmost ridge line.

  The front bracket 21 and the rear bracket 22 of the embodiment correspond to the bracket of the present invention, and the front shock absorber 29F and the rear shock absorber 29R of the embodiment correspond to the shock absorber of the present invention. The side wall part 29a, the thin part 29c, and the slits 29e and 29f of the embodiment correspond to the weak part of the present invention.

  According to the first configuration of the present invention, the front hood of the automobile is configured by connecting the hood skin to the upper surface of the hood frame, and the rear end of the front hood can swing up and down on the vehicle body via the hinge. A striker, which is pivotally supported and provided at a predetermined position rearward from the front end of the front hood, is locked to a hood lock provided on the vehicle body. The front part of the hood frame is closer to the front of the striker, and has a substantially flat frame body part and a shock absorber with a box structure that projects upward from the frame body part toward the lower surface of the hood skin. It is possible to absorb the collision energy of the entire frame main body by buckling in the front-rear direction, and the collision energy of the collision from above can be absorbed by crushing the shock absorption part of the frame main body. In any case of collision, an effective energy absorption effect can be obtained. Further, the shock absorbing portion has a box structure including left and right side wall portions extending in the front-rear direction and an upper wall portion that is connected between the upper portions of the left and right side wall portions and curves upward, so that the crushing allowance is sufficient. It is possible to increase the amount of energy absorption by securing it. Moreover, since the upper wall portion is composed of a plurality of surfaces that extend in the front-rear direction via a plurality of ridge lines extending in the left-right direction, not only can the deformation of the upper wall portion be promoted by using the ridge lines as broken lines, Since the upward projecting height from the frame main body is higher on the rear side than on the front side of the shock absorbing part, the upper wall part can be effectively deformed when a collision load is input from the front upper side. .

  Further, according to the second configuration of the present invention, since the number of ridge lines of the upper wall portion is larger on the rear side than on the front side of the shock absorbing portion, in any case of a collision from the front and a collision from above Also, the shock absorber can be appropriately deformed.

  Further, according to the third configuration of the present invention, since the weak portion that locally reduces the strength is formed in the shock absorbing portion, the energy absorption amount can be controlled by encouraging deformation of the shock absorbing portion starting from the weak portion. Can be made possible.

  Further, according to the fourth configuration of the present invention, the front hood includes a plurality of shock absorbing portions juxtaposed in the left-right direction, so that the shock absorbing performance is enhanced at an arbitrary position in the vehicle width direction of the front portion of the front hood. Can do.

  Moreover, according to the 5th structure of this invention, since the weak part was formed on the ridgeline, the deformation | transformation of the impact-absorbing part which makes a ridgeline a starting point can further be accelerated | stimulated.

  According to the sixth configuration of the present invention, the front bracket made of a thin plate that supports the front side of the striker includes a rear connection portion that is connected to the striker, and a vertical wall portion that rises upward from the rear connection portion via a broken line. And a front connection portion that extends forward from the upper portion of the vertical wall portion and is connected to the hood frame, so that when a collision load from the front is input to the front end of the hood frame, it is pushed rearward by the front connection portion. Since the vertical wall portion tilts backward with a fold line between the vertical wall portion and the rear connection portion as a fulcrum, a stroke in which the hood frame in front of the striker buckles in the front-rear direction can be secured and the collision energy can be absorbed. In addition, the rear bracket made of a thick plate that supports the rear side of the striker has multiple broken lines between the connection part with the striker and the connection part with the hood frame, so a collision load from above is input to the front part of the hood frame. Then, the rear bracket is bent at a plurality of broken lines and buckled in the vertical direction, so that the collision energy can be absorbed. In this way, the bracket strength required during normal opening and closing of the front hood while effectively absorbing the collision energy in both cases of a front hood collision and an upper collision. Can be secured.

  Further, according to the seventh configuration of the present invention, the hood frame has a plurality of broken lines between the connection portion with the rear bracket and the connection portion with the front bracket, so that the collision load from above is applied to the front portion of the hood frame. , The hood frame is bent at a plurality of broken lines and buckled in the vertical direction, so that the collision energy can be absorbed.

  Further, according to the eighth configuration of the present invention, the reinforcing member fixed to the front connection portion is opposed to the front surface of the vertical wall portion so that the front bracket can be reinforced so that the front bracket is reinforced by the reinforcing member. While ensuring the strength of the bracket required during normal opening and closing, etc., in the event of a collision from the front, the collision load is efficiently transmitted from the front connection part to the vertical wall part via the reinforcing member, and the vertical wall part is reliably secured Can be defeated backwards.

  Further, according to the ninth configuration of the present invention, the impact absorbing portion protrudes upward from the front and rear portions of the frame main body toward the lower surface of the hood skin. Absorbed by buckling in the front-rear direction, it is possible to absorb the collision energy of the collision from above by crushing the impact absorption parts on the front side and rear side of the hood frame. In this case, an effective energy absorption effect can be obtained.

  Further, according to the tenth configuration of the present invention, the front impact absorbing portion on the front side of the hood frame is bent upward and convex at all the ridge lines, so that when the impact load from the front side is input, the front impact is received. The absorption part can be easily buckled, and the rear impact absorption part on the rear side of the hood frame is bent upward at the ridge line except the rearmost ridge line, so when a collision load from the upper side is input The rear shock absorber can be easily buckled.

FIG. 1 is a perspective view of a front part of a vehicle body. (First embodiment) 2 is a cross-sectional view taken along line 2-2 of FIG. (First embodiment) FIG. 3 is an enlarged view of part 3 of FIG. (First embodiment) 4 is a cross-sectional view taken along line 4-4 of FIG. (First embodiment) FIG. 5 is a view taken in the direction of arrow 5 in FIG. (First embodiment) FIG. 6 is an explanatory diagram of the action at the time of collision from the front. (First embodiment) FIG. 7 is an explanatory diagram of the action at the time of collision from the front upper side. (First embodiment) FIG. 8 is an explanatory view of the action at the time of collision from the upper front side. (First embodiment) FIG. 9 corresponds to FIG. (Second Embodiment) FIG. 10 corresponds to FIG. (Second Embodiment) 11 is a cross-sectional view taken along line 11-11 of FIG. (Second Embodiment) FIG. 12 is an explanatory diagram of the action at the time of collision from the front. (Second Embodiment) FIG. 13 is an explanatory diagram of the action at the time of collision from the front upper side. (Second Embodiment) FIG. 14 is an explanatory view of the action at the time of collision from the upper front side. (Second Embodiment) FIG. 15 corresponds to FIG. (Third embodiment) FIG. 16 corresponds to FIG. (Third embodiment) 17 is a view in the direction of arrow 17 in FIG. (Third embodiment) FIG. 18 is an explanatory diagram of the action at the time of collision from the front. (Third embodiment) FIG. 19 is an explanatory diagram of the action at the time of a collision from the front upper side. (Third embodiment) FIG. 20 is an explanatory view of the action at the time of collision from the upper front side. (Third embodiment) FIG. 21 corresponds to FIG. (Fourth embodiment) 22 is a cross-sectional view taken along line 22-22 of FIG. (Fourth embodiment) FIG. 23 is an enlarged view of part 23 of FIG. (Fourth embodiment) 24 is an enlarged view of a portion 24 in FIG. (Fourth embodiment) 25 is a sectional view taken along line 25-25 in FIG. (Fourth embodiment) FIG. 26 is an explanatory diagram of the action at the time of collision from the front. (Fourth embodiment) FIG. 27 is an explanatory view of the action at the time of collision from the front upper side. (Fourth embodiment) FIG. 28 is an explanatory view of the action at the time of a collision from the upper front side. (Fourth embodiment) FIG. 29 is an explanatory diagram of the action at the time of collision from above. (Fourth embodiment)

15 front hood 16 hood frame 17 hood skin 19 front frame 21 front bracket (bracket)
21a Rear connection part 21b Vertical wall part 21c Front connection part 22 Rear bracket (bracket)
24 striker 27 hood lock 28 frame main body 29 shock absorber 29F front shock absorber (shock absorber)
29R Rear shock absorber (shock absorber)
29a Side wall part (fragile part)
29b Upper wall part 29c Thin part (fragile part)
29e slit (fragile part)
29f Slit (fragile part)
31 Reinforcing member A, B, C, D Surface d, e, f Edge line i, j, k Polygonal line

  Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. In addition, the front, back, right side, and left side in this specification are defined on the basis of the passenger | crew who seated in the driver's seat.

First embodiment

  As shown in FIGS. 1 and 2, a front hood (bonnet hood) 15 is disposed at a position sandwiched between a front bumper 11, left and right front fenders 12, 12 and a windshield 13 of an automobile and covers an upper portion of an engine room 14. The hood frame 16 constituting the skeleton and the hood skin 17 superimposed on the upper surface of the hood frame 16 are provided. The hood frame 16 includes a rear frame 18 formed by press-molding a steel plate and a front frame 19 formed by molding a synthetic resin. The rear frame 18 constitutes a rear portion of the hood frame 16 than the bulkhead 20. Reference numeral 19 denotes a front portion of the hood frame 16 than the bulkhead 20. The hood skin 17 is composed of a single smoothly curved steel plate, but the rear frame 18 includes a plurality of reinforcing ribs 18a and a plurality of openings 18b in order to improve rigidity and reduce the weight.

  As shown in FIGS. 2 and 5, the front bracket 21 is attached to the front end of the rear frame 18 so that the front portion of the hood frame 16 whose rear end is hinged to the vehicle body is locked to the upper portion of the bulkhead 20 in the closed position. The striker 24 is supported via the rear bracket 22 and the striker bracket 23. The front bracket 21 is formed by bending a rectangular steel plate with a plurality of broken lines extending in the left-right direction, and the front portion thereof is fixed to the front edge of the rear frame 18 by a combination of three rivets 25 and a weld w1.

  The rear bracket 22 is formed by bending a rectangular steel plate with a plurality of broken lines extending in the left-right direction, and its rear edge is welded to the front lower surface of the rear frame 18. Then, the rectangular striker bracket 23 to which the “U” -shaped striker 24 opening upward is welded w3 is welded to the rear edge of the front bracket 21 and the front edge of the rear bracket 22 w4 and w5. On the other hand, the hood lock 27 is supported by the support bracket 26 welded to the upper rear surface of the bulkhead 20, and the lock claw 27 a of the hood lock 27 is engaged with the striker 24, so that the front hood 15 is engaged in the closed position. Stopped.

  In a state where the striker 24 of the front hood 15 is locked to the hood lock 27, the front frame 19 of the hood frame 16 projects forward from the bulkhead 20 by a predetermined distance.

  As shown in FIGS. 2 to 4, the front frame 19 elongated in the left-right direction has its front edge and right and left side edges fixed to the peripheral edge of the hood skin 17 by caulking, and its rear edge is the three rivets. A number of rivets 25 including 25 are fixed to the front edge of the rear frame 18. The front frame 19 includes a substantially flat frame main body portion 28 and three shock absorbing portions 29 having the same shape and protruding upward from the frame main body portion 28 in a box shape.

  Each shock absorbing portion 29 has a pair of left and right pentagonal side wall portions 29a and 29a rising from the frame main body portion 28 through side fold lines a and a, and an upper wall connecting between the upper edges of both side wall portions 29a and 29a. Part 29b. The front wall and the rear edge of the upper wall portion 29b are connected to the frame main body portion 28 via the front fold line b and the rear fold line c, and four surfaces A, 3 are formed by three ridgelines d, e, and f extending in the left-right direction. It is divided into B, C, and D. The angles formed by the four planes A, B, C, and D at the three broken lines d, e, and f are convex toward the outside (upper side) of the shock absorbing portion 29. The thickness of the side wall portions 29a, 29a is thinner than the thickness of the upper wall portion 29b and the thickness of the frame main body portion 28, and the side wall portions 29a, 29a themselves are more than the upper wall portion 29b and the frame main body portion 28. It constitutes a vulnerable part.

  A groove-like thin portion 29c that reduces the thickness of the rear two ridgelines e and f and the lower surfaces of the ridgelines g and h formed in the left-right direction behind the shock absorbing portion 29. 2), and the strength of the front frame 19 is locally reduced by these thin portions 29c.

  Of the four surfaces A, B, C, and D of the upper wall portion 29 b of the shock absorbing portion 29, the largest surface B sandwiched between the ridge lines d and e is along the lower surface of the hood skin 17. Three adhesive application grooves 29d... Extending in the front-rear direction are formed on the surface B, and the surface B is formed by the adhesive 30 (see FIG. 2) applied to these adhesive application grooves 29d. Bonded to the lower surface of

  The protruding height of the upper wall portion 29 b upward from the frame main body portion 28 is higher on the rear side than on the front side of the shock absorbing portion 29. That is, the second ridge line e from the front on the rear side of the upper wall portion 29b is the highest. Of the three ridge lines d, e, and f, the first ridge line d from the front is on the front side of the shock absorbing portion 29, and the second and third ridge lines e and f from the front are on the shock absorbing portion 29. On the rear side. That is, the three ridge lines d, e, and f are densely arranged in the rear half of the shock absorbing portion 29.

  Next, the operation of the embodiment of the present invention having the above configuration will be described.

  When the automobile collides with an obstacle such as a pedestrian in front, the front part of the hood frame 16 protruding forward from the rigid bulkhead 20, that is, the part where the hood frame 16 is constituted by the front frame 19 is deformed. Absorbs collision energy.

  As shown in FIG. 6, for example, when a pedestrian's waist comes into contact with the front end of the front hood 15 and a collision load F <b> 1 is input from the front, each impact absorbing portion 29 of the front frame 19 of the hood frame 16 is moved in the front-rear direction. The front frame 19 is compressed and strongly bent by crushing the front fold line b, the ridge lines d, e, and f and the rear fold line c of the upper wall portion 29b and the ridge lines g and h behind the shock absorbing portion 29. Is buckled in the front-rear direction, and at the same time, the front portion of the hood skin 17 is bent downward, so that the front edge of the front hood 15 is retracted with a large stroke S1 and the collision energy is effectively absorbed.

  At this time, since the side wall portions 29a and 29a of the shock absorbing portion 29 are formed thin and easily broken, the buckling of the upper wall portion 29b can be promoted to enhance the energy absorbing effect. Moreover, since the groove-shaped thin part 29c ... is formed in the lower surface of ridgeline e, f, g, h, the bending of the front frame 19 in ridgeline e, f, g, h is promoted, and the energy absorption effect is further increased. Enhanced.

  As shown in FIG. 7, for example, when a pedestrian's thigh comes into contact with the front portion of the front hood 15 and a collision load F <b> 2 from the front upper side is input, the position of the striker 24 locked to the hood lock 27 is set as a fulcrum. Thus, a downward bending moment acts on the front frame 19 in front of the bulkhead 20, and the front portion of the hood frame 16 is bent downward and deformed. At this time, the thin side walls 29a and 29a of the respective shock absorbing portions 29 of the front frame 19 are easily broken, so that the ridgelines d, e, and f of the upper wall portion 29b, the rear bent line c, and the shock absorption are obtained. Since the rear ridge lines g and h of the portion 29 are deformed downward while being stretched, the front edge of the front hood 15 moves backward and downward with a large stroke S2 to effectively absorb the collision energy.

  Also in this case, the deformation of the shock absorbing portion 29 is promoted by the breakage of the side wall portions 29a, 29a of the shock absorbing portion 29 and the expansion of the thin portions 29c ... on the lower surfaces of the ridge lines e, f, g, h. Therefore, the energy absorption effect is enhanced.

  As shown in FIG. 8, for example, when a pedestrian's head comes into contact with the front portion of the front hood 15 and a collision load F3 from the upper front is input, the front frame 19 is moved from the relatively hard head. Since a local load acts on the shock absorbing portion 29, the side wall portions 29a and 29a formed on the thin portion of the shock absorbing portion 29, the side broken lines a and a around the shock absorbing portion 29, and the front bent line b Further, the crushing energy is effectively absorbed by crushing so that the rear broken line c is broken and the upper wall portion 29b is crushed.

  As described above, in the case of a collision from the front with respect to the front hood 15, the collision energy is absorbed by the buckling in the front-rear direction of the entire front frame 19, and the collision energy from the front upper side or the upper front is absorbed by the front frame. It is possible to absorb by crushing the 19 impact absorbing portions 29, and an effective energy absorbing effect can be obtained in any case of a collision from the front and a collision from above. In addition, since the shock absorbers 29 ... function as reinforcing ribs and the rigidity of the front frame 19 is increased during normal times other than during a collision, the shocks associated with the opening and closing of the front hood 15 can be sufficiently resisted.

  Further, the shock absorbing portion 29 of the front frame 19 has a box structure that includes left and right side wall portions 29a, 29a and an upper wall portion 29b that connects the upper portions thereof and curves upwardly to be convex. The amount of energy absorption can be increased by securing a sufficient margin. The upper wall portion 29b is composed of four surfaces A, B, C, and D continuous in the front-rear direction via a plurality of ridge lines d, e, and f that extend in the left-right direction, so that the ridge lines d, e, and f are broken lines. Not only can the deformation of the upper wall portion 29b be promoted, but the protruding height of the upper wall portion 29b upward from the frame main body portion 28 is higher on the rear side than the front side of the shock absorbing portion 29. When the load is input from the front upper side, the upper wall portion 29b can be effectively deformed. Moreover, since the number of ridge lines d, e, and f of the upper wall portion 29b is larger on the rear side than on the front side of the shock absorbing portion 29, the shock absorbing portion can be used in both cases of a collision from the front and a collision from above. 29 can be appropriately deformed.

  Further, the energy absorption amount can be controlled by encouraging deformation of the shock absorbing portion 29 starting from the ridgelines e and f formed with the thin side walls 29a and 29a or the thin portion 29c of the shock absorbing portion 29. can do. Moreover, since the front frame 19 includes the three shock absorbing portions 29 arranged in the left-right direction, the shock absorbing performance can be enhanced at an arbitrary position in the vehicle width direction of the front portion of the front hood 15.

  Next, a second embodiment of the present invention will be described with reference to FIGS. In the first embodiment, the front frame 19 is made of synthetic resin, but the front frame 19 of the second embodiment is made of metal.

Second embodiment

  As shown in FIGS. 9 to 11, slits 29 e and 29 e are formed on the side fold lines a and a where the left and right wall portions 29 a and 29 a rise from the frame main body portion 28. In addition, slits 29f are formed on the front and rear edges (ridge lines d and e) and the left and right side edges of the largest surface B among the four surfaces A, B, C and D of the upper wall portion 29b of the shock absorbing portion 29. The These slits 29e, 29e, 29f... Constitute a fragile part of the shock absorbing part 29. Furthermore, ridge lines g and h extending in the left-right direction are formed behind the shock absorbing portion 29.

  Next, the operation of the embodiment of the present invention having the above configuration will be described.

  As shown in FIG. 12, for example, when a pedestrian's waist contacts the front end of the front hood 15 and a collision load F1 is input from the front, the shock absorbing member 29 is compressed in the front-rear direction, and the front wall 29b is The front fold line a, the ridge lines d, e, and f, the rear fold line b, and the ridge lines g and h behind the shock absorbing portion 29 are crushed and bent strongly, so that the front frame 19 is buckled in the front-rear direction. When the front portion of the hood skin 17 is bent downward, the front edge of the front hood 15 is retracted with a large stroke S1, and the collision energy is effectively absorbed.

  At this time, the side wall portions 29a, 29a of the shock absorbing portion 29 are weakened by the slits 29e, 29e of the side fold lines a, a and easily deformed, and the upper wall portion 29b is a slit 29f that surrounds the surface B. Since it is weakened and easily deforms, the buckling of the shock absorbing portion 29 can be promoted to enhance the energy absorption effect.

  As shown in FIG. 13, for example, when a pedestrian's thigh comes into contact with the front portion of the front hood 15 and a collision load F <b> 2 is input from the front upper side, the position of the striker 24 locked to the hood lock 27 is set as a fulcrum. Thus, a downward bending moment acts on the front frame 19 in front of the bulkhead 20, and the front portion of the hood frame 16 is bent downward and deformed. At this time, the side wall portions 29a and 29a weakened by the slits 29e and 29e of the shock absorbing portions 29 of the front frame 19 are easily deformed, so that the ridgelines d, e, and f of the upper wall portion 29b and the rear bent line are formed. b and the rear edge lines g and h of the shock absorbing portion 29 are deformed downward while being stretched, so that the front edge of the front hood 15 moves backward and downward with a large stroke S2 to effectively absorb the collision energy.

  Also in this case, the slits 29e, 29e, 29f,... Promote the crushing deformation of the shock absorbing portion 29, so that the energy absorption effect is enhanced.

  As shown in FIG. 14, for example, when a pedestrian's head comes into contact with the front portion of the front hood 15 and a collision load F3 from the upper front is input, the front frame 19 is moved from the relatively hard head. Since a local load acts on the shock absorbing portion 29, the side wall portions 29a and 29a of the shock absorbing portion 29, the side broken lines a and a surrounding the shock absorbing portion 29, the front bent line b and the rear bent line c. Or, the ridgelines e, f, g, etc. of the upper wall portion 29b of the shock absorbing portion 29 are deformed or broken so that the shock absorbing portion 29 is crushed so that the collision energy is effectively absorbed.

  Also in this case, the slits 29e, 29e, 29f,... Promote the crushing deformation of the shock absorbing portion 29, so that the energy absorption effect is enhanced.

  As described above, the slits 29e, 29e, 29f,... That weaken the shock absorbing portion 29 are used as starting points to promote deformation of the shock absorbing portion 29, thereby making it possible to control the amount of energy absorption.

  Hereinafter, a third embodiment of the present invention will be described with reference to FIGS. In the third embodiment, the front frame 19 is. Although it is made of a synthetic resin as in the first embodiment, it may be made of metal.

Third embodiment

  As shown in FIGS. 15 to 17, the front bracket 21 is attached to the front end of the rear frame 18 so that the front portion of the hood frame 16 whose rear end is hinged to the vehicle body is locked to the upper portion of the bulkhead 20 in the closed position. The striker 24 is supported via the rear bracket 22 and the striker bracket 23. The front bracket 21 is formed by bending a rectangular steel plate having a relatively thin plate thickness with a plurality of fold lines extending in the left-right direction, and a rear connection portion 21a extending in a substantially horizontal direction and a fold line i at the front end of the rear connection portion 21a. A vertical wall portion 21b that rises in an inverted “J” shape from above, and a front connection portion 21c that extends in a substantially horizontal direction from the front end of the vertical wall portion 21b. The front connection portion 21c is a front edge of the rear frame 18. The three rivets 25 and the weld w1 are used together.

  The rear bracket 22 is formed by bending a rectangular steel plate having a relatively large thickness along a plurality of fold lines j extending in the left-right direction, and its rear edge is welded to the front lower surface of the rear frame 18 w2. A portion sandwiched between the weld w1 and the weld w2 of the rear frame 18 is bent at a plurality of broken lines k extending in the left-right direction. Then, the rectangular striker bracket 23 to which the “U” -shaped striker 24 opening upward is welded w3 is welded to the rear edge of the front bracket 21 and the front edge of the rear bracket 22 w4 and w5. On the other hand, the hood lock 27 is supported by the support bracket 26 welded to the upper rear surface of the bulkhead 20, and the lock claw 27 a of the hood lock 27 is engaged with the striker 24, so that the front hood 15 is engaged in the closed position. Stopped.

  In a state where the striker 24 of the front hood 15 is locked to the hood lock 27, the front frame 19 of the hood frame 16 projects forward from the bulkhead 20 by a predetermined distance. A rod-shaped reinforcing member 31 extending in the left-right direction is fixed to the rear end of the front frame 19, and this reinforcing member 31 abuts against the front surface of the vertical wall portion 21 b that rises upward from the broken line i of the front bracket 21. Opposite possible.

  Next, the operation of the embodiment of the present invention having the above configuration will be described.

  As shown in FIG. 18, when a rearward load is applied from the rear end of the front frame 19 to the front connection portion 21 c of the front bracket 21 when the automobile collides with an obstacle such as a pedestrian, the front bracket Since 21 is thinner than the rear bracket 22, the front connection portion 21c is located higher than the rear connection portion 21a, and therefore, a broken line between the rear connection portion 21a and the vertical wall portion 21b. A large bending moment acts on i, and the vertical wall portion 21b is bent at the broken line i and deformed to fall backward. When the front bracket 21 is tilted rearward in this way, the rear end of the front frame 19 can make an extra stroke to the rear, and the energy absorption effect is further enhanced.

  As shown in FIG. 19, for example, when a pedestrian's thigh comes into contact with the front portion of the front hood 15 and a collision load F <b> 2 is input from the front upper side, the position of the striker 24 locked to the hood lock 27 is a fulcrum. Thus, a downward bending moment acts on the front frame 19 in front of the bulkhead 20, and the front portion of the hood frame 16 is bent downward and deformed. At this time, the thin side walls 29a and 29a of the respective shock absorbing portions 29 of the front frame 19 are easily broken, so that the ridgelines d, e, and f of the upper wall portion 29b, the rear bent line c, and the shock absorption are obtained. Since the rear ridge lines g and h of the portion 29 are deformed downward while being stretched, the front edge of the front hood 15 moves backward and downward with a large stroke S2 to effectively absorb the collision energy.

  Also in this case, the deformation of the shock absorbing portion 29 is promoted by the breakage of the side wall portions 29a, 29a of the shock absorbing portion 29 and the expansion of the thin portions 29c ... on the lower surfaces of the ridge lines e, f, g, h. Therefore, the energy absorption effect is enhanced.

  As shown in FIG. 20, when a pedestrian's head comes into contact with the front portion of the front hood 15 (above the bulkhead 20) and a collision load F3 from the upper front is input, the rear frame 18 The front bent line k ... and the rear bracket 22 bent line j ... are bent and crushed so as to be crushed downward, and the collision energy from above is effectively absorbed.

  For example, when a pedestrian's head comes into contact with the front side of the bulkhead 20 and a collision load F3 from the upper front is input, the shock absorbing portion of the front frame 19 from the relatively hard head. Since a local load acts on the side wall 29, the side wall portions 29 a and 29 a formed thinly on the shock absorbing portion 29, the side broken lines a and a around the shock absorbing portion 29, the front bent line b and the rear bent line c Is collapsible so that the upper wall portion 29b is crushed and broken, so that the collision energy is effectively absorbed.

  As described above, in the case of a collision with the front hood 15 from the front, the collision energy is absorbed by the buckling in the front-rear direction of the entire front frame 19, and the collision energy from above is absorbed by the rear frame 18 and the rear bracket 22. It is possible to absorb by crushing at the broken lines k ..., j ... or by crushing the impact absorbing portion 29 of the front frame 19, and effective energy absorption in both cases of collision from the front and collision from above. An effect can be obtained. In addition, during normal times other than a collision, the shock absorbing portion 29 functions as a reinforcing rib to increase the rigidity of the front frame 19, and the reinforcing member 31 increases the rigidity of the front bracket 21. It can sufficiently withstand impacts associated with opening and closing.

  Hereinafter, a fourth embodiment of the present invention will be described with reference to FIGS.

Fourth embodiment

  As shown in FIGS. 21 to 23, a front hood (bonnet hood) 15 that is disposed at a position sandwiched between a front bumper 11, left and right front fenders 12, 12 and a windshield 13 of an automobile and covers the upper portion of the engine room 14 is The hood frame 16 constituting the skeleton and the hood skin 17 superimposed on the upper surface of the hood frame 16 are provided. The hood skin 17 is formed of a single steel plate that is smoothly curved, but the hood frame 16 obtained by molding a synthetic resin with a mold is formed in a shape having complicated irregularities.

  The hood frame 16 fixed by caulking to the periphery of the hood skin 17 includes a substantially flat frame main body 28 and a plurality of shock absorbing parts 29F, 29R,. Is provided. The shock absorbing portions 29F, 29R,... Are arranged along five rows extending in the left-right direction, the front two rows of front shock absorbing portions 29F, and the rear three rows of rear shock absorbing portions 29R. ... and the shape is different.

  The front impact absorbing portion 29F in the first row from the front includes a pair of left and right pentagonal side wall portions 29a and 29a rising from the frame main body portion 28 through side fold lines a and a, and upper side walls 29a and 29a. And an upper wall portion 29b connecting the edges. The front wall and the rear edge of the upper wall portion 29b are connected to the frame main body portion 28 via the front fold line b and the rear fold line c, and four surfaces A, 3 are formed by three ridgelines d, e, and f extending in the left-right direction. It is divided into B, C, and D. The angles formed by the four planes A, B, C, and D at the three broken lines d, e, and f are convex toward the outside (upper side) of the front impact absorbing portion 29F. The thickness of the side wall portions 29a, 29a is thinner than the thickness of the upper wall portion 29b and the thickness of the frame main body portion 28, and the side wall portions 29a, 29a themselves are more than the upper wall portion 29b and the frame main body portion 28. It constitutes a vulnerable part.

  A groove-like thin portion 29c that reduces the thickness of the lower surface of the two rear ridge lines e and f and the lower surface of the ridge lines g and h formed in the left-right direction behind the front impact absorbing portion 29F. (Refer to the circle in FIG. 22) is formed, and the strength of the front impact absorbing portion 29F is locally reduced by these thin portions 29c.

  Of the four surfaces A, B, C, and D of the upper wall portion 29b of the front impact absorbing portion 29F, the largest surface B sandwiched between the ridge lines d and e is along the lower surface of the hood skin 17. Three adhesive application grooves 29d... Extending in the front-rear direction are formed on the surface B, and the surface B is the hood skin 17 by the adhesive 30 (see FIG. 22) applied to these adhesive application grooves 29d. Bonded to the lower surface of

  The upward projecting height of the upper wall portion 29b from the frame main body portion 28 is higher on the rear side than on the front side of the front impact absorbing portion 29F. That is, the second ridge line e from the front on the rear side of the upper wall portion 29b is the highest. Of the three ridge lines d, e, and f, the first ridge line d from the front is on the front side of the front shock absorber 29F, and the second and third ridge lines e and f from the front are the front shocks. It exists in the rear part side of the absorption part 29F. That is, the three ridgelines d, e, and f are densely arranged in the rear half of the front impact absorbing portion 29F.

  The shape of the front impact absorbing portion 29F in the second row is similar to the shape of the front impact absorbing portion 29F in the first row described above, but there are some differences. That is, the front shock absorbing portion 29F in the second row is different from the front shock absorbing portion 29F in the first row in that the surface B on which the adhesive application grooves 29d are formed extends in parallel with the frame main body portion 28. The other shapes are the same.

  As shown in FIGS. 21, 24 and 25, the shape of the rear shock absorber 29R in the third row to the fifth row is similar to the shape of the front shock absorber 29F in the second row described above. There is a difference. In other words, the front shock absorbing portion 29F has the surfaces A to D bent upward at all the ridgelines d, e, and f, but the rear shock absorbing portion 29R has the first and second surfaces A to C from the front. The ridge lines d and e are bent upward and the surfaces C and D are bent downward at the third ridge line f from the front, and the other shapes are the same.

  Next, the operation of the embodiment of the present invention having the above configuration will be described.

  As shown in FIG. 26, for example, when a pedestrian's waist comes into contact with the front end of the front hood 15 and a collision load F1 from the front is input, the front impact absorbing portion 29F in the first row of the hood frame 16 is moved in the front-rear direction. The front fold line b, the ridge lines d, e, and f and the rear fold line c of the upper wall portion 29b and the ridge lines g and h on the rear side of the front impact absorbing portion 29F are crushed and strongly bent so that the hood frame is compressed. 16 is buckled in the front-rear direction, and at the same time, the front portion of the hood skin 17 is bent downward, so that the front edge of the front hood 15 is retracted by a large stroke S1 and the collision energy is effectively absorbed.

  At this time, since the side wall portions 29a and 29a of the front impact absorbing portion 29F are formed thin and easily broken, the buckling of the upper wall portion 29b can be promoted to enhance the energy absorbing effect. Moreover, since the groove-shaped thin part 29c ... is formed in the lower surface of ridgeline e, f, g, h, the bending of the hood frame 16 in ridgeline e, f, g, h is promoted, and the energy absorption effect is further enhanced. It is done.

  As shown in FIG. 27, for example, when a pedestrian's thigh comes into contact with the front portion of the front hood 15 and a collision load F2 is input from the front upper side, the position of the striker 24 locked to the hood lock 27 is set as a fulcrum. Thus, a downward bending moment acts on the hood frame 16 in front of the bulkhead 20, and the front portion of the hood frame 16 is bent downward and deformed. At this time, the side wall portions 29a and 29a formed in the thin wall of the front shock absorbing portion 29F in the first row of the hood frame 16 are easily broken, so that the ridgelines d, e, and f of the upper wall portion 29b and the rear bent line are formed. c and the rear ridge lines g and h of the front impact absorbing portion 29F are deformed downward while being stretched, so that the front edge of the front hood 15 is moved backward by a large stroke S2 to effectively absorb the collision energy. The

  Further, since the collision load is applied to the front impact absorbing portion 29F in the second row of the hood frame 16, the front impact absorbing portion 29F is crushed so as to fall backward and the collision energy is effectively absorbed.

  Also in these cases, the deformation of the front impact absorbing portion 29F is promoted by the breakage of the side wall portions 29a and 29a of the front impact absorbing portion 29F and the expansion of the thin portions 29c. Therefore, the energy absorption effect is enhanced.

  As shown in FIG. 28, for example, when a pedestrian's head comes into contact with the upper position of the bulkhead 20 of the front hood 15 and a collision load F3 from the upper front is input, a relatively hard head Since a local load acts on the front impact absorbing portion 29F in the second row from the front of the hood frame 16, the side wall portions 29a and 29a formed on the thin portion of the front impact absorbing portion 29F and the impact absorbing portion Collision energy is effectively absorbed by crushing so that the side broken lines a, a, the front bent line b, and the rear bent line c around 29 are broken and the upper wall part 29b is crushed.

  As shown in FIG. 29, for example, when a pedestrian's head comes into contact with the rear position of the front hood 15 and a collision load F4 is input from above, the hood frame 16 3 is moved from a relatively hard head. Since a local load acts on the rear shock absorber 29R in the fifth to fifth rows, the side walls 29a and 29a formed on the thin wall of the rear shock absorber 29R and the side portions around the rear shock absorber 29R By collapsing so that the broken lines a, a, the front bent line b, and the rear bent line c are broken and the upper wall part 29b is crushed, the collision energy is effectively absorbed.

  The front load 15 is characterized in that the direction of the collision load input from the pedestrian's lower back and thighs is closer to the front of the front hood 15, but in this case the front impact absorbing portion 29F that collapses has the ridge line f facing upward The front impact absorbing portion 29F can be reliably crushed when the collision load is input from the front side. On the other hand, the direction of the collision load input from the head of the pedestrian to the rear portion of the front hood 15 is characterized by being upward. In this case, the rear impact absorbing portion 29R that collapses has a ridge line f that protrudes downward. Since it is bent, the rear impact absorbing portion 29R can be reliably crushed when a collision load is input from above.

  As described above, in the case of a collision from the front with respect to the front hood 15, the collision energy is absorbed by buckling in the front-rear direction of the entire hood frame 16, and the collision energy from the front upper side or the upper side is absorbed by the front portion of the hood frame 16. Alternatively, it can be absorbed by the crushing of the rear impact absorbing portions 29F and 29R, and an effective energy absorbing effect can be obtained in any case of a collision from the front and a collision from above. Moreover, since the front and rear impact absorbing portions 29F, 29R, ... function as reinforcing ribs to increase the rigidity of the hood frame 16 during normal times other than the time of a collision, it is sufficient for impacts associated with the opening and closing of the front hood 15. Can withstand.

  The front and rear shock absorbing portions 29F and 29R of the hood frame 16 have a box structure including left and right side wall portions 29a and 29a, and an upper wall portion 29b that is curved upwardly by connecting the upper portions thereof. Therefore, the amount of energy absorption can be increased by sufficiently securing the crushing allowance. The upper wall portion 29b is composed of four surfaces A, B, C, and D continuous in the front-rear direction via a plurality of ridge lines d, e, and f that extend in the left-right direction, so that the ridge lines d, e, and f are broken lines. Not only can the deformation of the upper wall portion 29b be promoted, but in the upper shock absorbing portion 29f in the first row from the front, the protruding height of the upper wall portion 29b upward from the frame body portion 28 is the front and rear portions. Since it is higher on the rear side than the front side of the shock absorbing parts 29F, 29R, the upper wall part 29b can be effectively deformed when a collision load is input from the front upper side. Moreover, since the number of ridge lines d, e, and f of the upper wall portion 29b is larger on the rear side than on the front side of the front and rear shock absorbing portions 29F and 29R, any of the collision from the front and the collision from above Even in this case, the front and rear shock absorbing portions 29F and 29R can be appropriately deformed.

  Further, the front and rear shock absorbing portions 29F and 29R are deformed starting from the ridgelines e and f forming the thin side walls 29a and 29a or the thin portion 29c of the front and rear shock absorbing portions 29F and 29R. By prompting, it is possible to control the amount of energy absorption.

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.

  For example, in the first to third embodiments, the front frame 19 includes three shock absorbing portions 29..., But the number of shock absorbing portions 29 is arbitrary.

  In the embodiment, the upper wall portion 29b of the shock absorbing portions 29, 29F, and 29R includes three ridge lines d, e, and f, but the number of ridge lines is arbitrary.

  In the first and fourth embodiments, the fragile portions of the shock absorbing portions 29, 29F, and 29R are configured by the thin portions 29c and 29c formed on the ridge lines e and f, or the thin sidewall portions 29a and 29a themselves. Although comprised, a weak part can be comprised by the opening and notch which were formed in the shock absorption part 29. FIG.

  In the second embodiment, the fragile part of the shock absorbing part 29 is constituted by slits 29e, 29e, 29f..., But it can be constituted by openings, notches or the like.

  In the first to third embodiments, the rear frame 18 and the front frame 19 are configured as separate members, but they can be configured as a single member.

  In the fourth embodiment, five front shock absorbers 29F in the front two rows are arranged in the first and second rows, respectively, and the rear shock absorbers 29R in the rear three rows are arranged. 4 is arranged in the third column, three in the fourth column, and four in the fifth column, but the number of these columns and the number of arrangement are arbitrary. However, in the first and second rows, it is desirable to arrange at least one front impact absorbing portion 29F at the center in the left-right direction so as to be positioned above the hard bulkhead 20 and the hood lock 27. In the third to fifth rows, the upper part of the hard engine arranged in the center of the engine room, the upper part of the hard upper member arranged along the left and right side edges of the engine room, and the rear edge of the engine room are arranged. It is desirable to disperse and arrange the plurality of rear impact absorbing portions 29R so as to be located above the hard dashboard upper.

Claims (10)

A rear end of a front hood (15) formed by connecting a hood skin (17) to the upper surface of the hood frame (16) is pivotally supported on the vehicle body via a hinge so as to be swingable up and down, and the front hood (15) In a front hood structure of an automobile in which a striker (24) provided at a predetermined position rearward from the front end of the vehicle is engaged with a hood lock (27) provided on a vehicle body,
The hood frame (16) has a substantially flat frame main body portion (28) in front of the striker (24) and from the frame main body portion (28) toward the lower surface of the hood skin (17). A shock absorbing portion (29, 29F, 29R) having a box structure projecting upward; the shock absorbing portion (29, 29F, 29R) includes left and right side wall portions (29a) extending in the front-rear direction; And an upper wall portion (29b) that curves upward and connects the upper portions of the side wall portions (29a), and the upper wall portion (29b) has a plurality of ridge lines (d, e, f) extending in the left-right direction. And a plurality of surfaces (A, B, C, D) continuous in the front-rear direction, and the upward projection height of the upper wall portion (29b) from the frame body portion (28) is the shock absorption. Front side of the part (29, 29F, 29R) Front hood structure of a motor vehicle, characterized in that high in remote rear side.   The number of the ridge lines (d, e, f) of the upper wall portion (29b) is larger on the rear side than on the front side of the shock absorbing portion (29, 29F, 29R). 1. A front hood structure for an automobile according to 1.   The fragile part (29a, 29c, 29d, 29e) which reduces the strength locally is formed in the shock absorbing part (29, 29F, 29R). The front hood structure of an automobile described in 1.   The automobile according to any one of claims 1 to 3, wherein the front hood (15) includes a plurality of the shock absorbing parts (29, 29F, 29R) juxtaposed in the left-right direction. Front hood structure.   The front hood structure for an automobile according to claim 3, wherein the fragile portion (29c, 29f) is formed on the ridge line (d, e, f). Brackets (21, 22) for fixing the striker (24) to the hood frame (16) include a front bracket (21) made of a thin plate supporting the front side of the striker (24), and the striker (24). It consists of a rear bracket (22) consisting of a thick plate that supports the rear side,
The front bracket (21) includes a rear connection portion (21a) connected to the striker (24), and a vertical wall portion (21b) rising upward from the rear connection portion (21a) via a broken line (i). And a front connection part (21c) that extends forward from the upper part of the vertical wall part (21b) and is connected to the hood frame (16),
The said rear bracket (22) has several broken lines (j) between a connection part with the said striker (24), and a connection part with the said hood frame (16), The Claims 1- Claim characterized by the above-mentioned. 5. The front hood structure for an automobile according to any one of 4 above.   The hood frame (16) has a plurality of broken lines (k) between a connection portion with the rear bracket (21) and a connection portion with the front bracket (22), according to claim 6, The vehicle front hood structure described.   The reinforcing member (31) fixed to the front connection portion (21c) is opposed to the front surface of the vertical wall portion (21b) so as to be in contact with the front wall connecting portion (21c). Car front hood structure.   The said impact-absorbing part (29F, 29R) protrudes upwards toward the lower surface of the said food skin (17) from the front part and rear part of the said frame main-body part (28), The Claims 1- Claim characterized by the above-mentioned. 5. The front hood structure for an automobile according to any one of 4 above.   The front shock absorbing portion (29F) on the front side of the hood frame (16) is bent upwardly at all the ridge lines (d, e, f), and the rear shock absorbing portion on the rear side of the hood frame (16). 10. The front hood structure for an automobile according to claim 9, wherein the portion (29R) is bent upward and convex along the ridge line (d, e) excluding the rearmost ridge line (f).

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