Shock absorption member

Abstract

A shock absorption member (1) that is to be provided between an outer panel of a vehicle and door trim that is attached to the outer panel comprises a first box-shaped part (10) that has a box shape that is open in one direction, two second box-shaped parts (20) that have a box shape that is open in the direction opposite the direction in which the first box-shaped part (10) is open and are connected to respective sides of the first box-shaped part (10), and two beam plate parts (30) that have a flat plate shape that is parallel to a first bottom wall (11) of the first box-shaped part (10) and connect the two second box-shaped parts (20) at a position that is further to the open side of the first box-shaped part (10) than the first bottom wall (11).

Description

Impact absorbing material

[0001] The present invention relates to an impact absorbing member provided between an outer panel and a door trim of a vehicle.

[0002] A shock absorbing member attached to a door trim has been proposed, which includes a base plate disposed opposite the door trim, a plurality of legs protruding from the base plate toward the door trim, and a plurality of flat rigid walls protruding from the base plate toward the door trim (Patent Document 1).The invention of Patent Document 1 is intended to absorb the shock when an external force acts in a direction that brings the base plate of the shock absorbing member and the door trim closer together, such as when a side impact is applied to the vehicle, by causing the plurality of legs and the plurality of rigid walls to bend and deform at desired locations.

[0003] If a flat rigid wall portion protrudes from the base plate toward the door trim in this manner, when the rigid wall portion is pressed toward the door trim by an impact, the tip of the rigid wall portion that makes linear contact with the door trim may slide relative to the door trim. In this case, the rigid wall portion may deform in an unintended location, preventing it from achieving the desired impact absorption function. Therefore, the invention of Patent Document 1 provides a restricting piece on the door trim, which holds the tip of the rigid wall portion in place to prevent the rigid wall portion from sliding. Therefore, in addition to attaching the impact absorbing member to the door trim, it is necessary to process the door trim as well, which increases the effort and cost.

[0004] Furthermore, the shock absorbing member of Patent Document 1 has four flat rigid wall portions crossed to form an X-shape, which makes the mold structure for manufacturing complex. In addition, the shock absorbing member of Patent Document 1 has a first reinforcing rib and a second reinforcing rib on each rigid wall portion. Two first reinforcing ribs are provided on one side of each rigid wall portion, and their length is approximately two-thirds of the length of the rigid wall portion. Two second reinforcing ribs are provided on the other side of each rigid wall portion, and their length spans the entire length of the rigid wall portion. The protruding lengths of the first reinforcing ribs and second reinforcing ribs from the rigid wall portion decrease toward the tip of the rigid wall portion. Thus, the shock absorbing member of Patent Document 1 has multiple ribs of different lengths on each flat plate, and the protruding lengths of each rib also vary. As a result, the shock absorbing member of Patent Document 1 has the problem of a very complex mold structure, making it difficult to manufacture.

[0005] Patent No. 6608796

[0006] In view of the above-mentioned circumstances, the present invention aims to provide an impact absorbing member that can absorb impacts applied to a vehicle from the side, which does not require processing of the door trim and can be easily manufactured.

[0007] In order to solve the above problems, the impact absorbing member of the present invention is "an impact absorbing member provided between an outer panel of a vehicle and a door trim attached to the outer panel, and comprises: a first box-shaped portion that is box-shaped and opens in one direction; two second box-shaped portions that are box-shaped and open in the opposite direction to the opening of the first box-shaped portion and are connected to both sides of the first box-shaped portion; and two beam plate portions that are flat and parallel to the bottom wall of the first box-shaped portion and connect the two second box-shaped portions at a position closer to the opening of the first box-shaped portion than the bottom wall."

[0008] The impact absorbing member of this configuration includes one first box-shaped portion and two second box-shaped portions connected to both sides of the first box-shaped portion. The first box-shaped portion and the second box-shaped portion open in opposite directions. This impact absorbing member is positioned between an outer panel and a door trim, with the bottom wall of the first box-shaped portion facing the door trim and the bottom wall of the second box-shaped portion facing the outer panel. In this state, when an impact acts on the outer panel due to a side collision of the vehicle, the bottom walls of the two second box-shaped portions abut against the outer panel, and the bottom wall of the first box-shaped portion abuts against the door trim. As a result, an external force (load) acts on the impact absorbing member in a direction that brings the bottom walls of the first box-shaped portion and the second box-shaped portion closer to each other.

[0009] Because the first box-shaped portion bears this external force with one force and the second box-shaped portion bears it with two, the first box-shaped portion bears a larger load per portion and is therefore more susceptible to deformation. Therefore, in the early stages of deformation of the shock-absorbing member, the first box-shaped portion continues to bear the load while deforming. Once the deformation of the first box-shaped portion progresses to a certain extent and buckles, the two second box-shaped portions begin to deform. Furthermore, after the portion of the first box-shaped portion closer to the bottom wall than the beam plate portion is crushed, the beam plate portion begins to bear the load, and as the beam plate portion bears the load, the deformation of the second box-shaped portion progresses. By sequentially deforming the first box-shaped portion and the second box-shaped portion in this way, the shock-absorbing member exhibits sufficient shock-absorbing function, as will be described in detail below.

[0010] Furthermore, if the two second box-shaped portions were to fall toward each other during deformation, interference between the components could prevent the desired deformation. In response to this, the impact absorbing member of this configuration includes a beam plate portion that connects the two second box-shaped portions at a position closer to the opening than the bottom wall of the first box-shaped portion. This beam plate portion effectively prevents the two second box-shaped portions from approaching each other during deformation.

[0011] As described above, in the impact absorbing member of this configuration, the bottom wall of the first box-shaped portion makes surface contact with the door trim. Therefore, compared to the prior art (Patent Document 1) in which a flat member makes linear contact with the door trim, the impact absorbing member is less likely to slide relative to the door trim. This prevents the components of the first box-shaped portion from bending in unintended locations and allows for desired deformation. Furthermore, because the bottom wall of the first box-shaped portion does not slide relative to the door trim, unlike the prior art, there is no need to process the door trim to hold the components of the impact absorbing member. Therefore, the impact absorbing member can be installed between the outer panel and the door trim with less effort and cost than the prior art.

[0012] In addition, since the impact absorbing member of this configuration is formed by connecting three box-shaped members, the structure of the mold for manufacturing is simple, making it easy to manufacture and possible to manufacture at low cost.

[0013] In addition to the above configuration, the impact absorbing member according to the present invention can be configured such that "the first box-shaped portion has a quadrangular pyramid shape in which the area enclosed by the opening edge is larger than the area of ​​the bottom wall."

[0014] If, during the deformation process of the first box-shaped portion, the component on the opening side were to deform so as to fall toward the internal space of the box, interference between the components could hinder the desired progression of deformation.

[0015] In contrast, in this configuration, the first box-shaped portion has a truncated quadrangular pyramid shape in which the area enclosed by the opening edge is larger than the area of ​​the bottom wall. In other words, the two side walls that make up the peripheral wall of the first box-shaped portion are inclined so that they move farther apart toward the opening. As a result, during the deformation process that progresses after the bottom wall of the first box-shaped portion abuts against the door trim, the side walls are more likely to deform toward the exterior space of the box than toward the interior space of the box. This effectively prevents interference between components during the deformation process, allowing the first box-shaped portion to undergo the desired deformation.

[0016] In addition to the above configuration, the impact absorbing member of the present invention can be configured such that "the first box-shaped portion has a plurality of bead portions protruding from at least one of the outer surface or the inner surface and extending from the bottom wall toward the opening edge."

[0017] The rigidity of the first box-shaped portion can be changed by varying the number of bead portions and the protruding height, which allows the degree of impact absorption until the first box-shaped portion is almost crushed during a side collision to be adjusted.

[0018] In addition, the bead portion increases the rigidity of the first box-shaped portion, preventing the first box-shaped portion from deforming and tipping toward the interior or exterior space of the box during a side collision. As a result, when an external force acting in the width direction of the vehicle is applied during a side collision, the first box-shaped portion can be deformed and crushed by compression.

[0019] Furthermore, the impact absorbing member of this configuration, in which the bead portion is provided on the outer or inner surface of the box-shaped portion, can be manufactured using a mold with a simpler structure than the impact absorbing member of Patent Document 1, in which ribs protrude from the front and back surfaces of a flat plate-shaped member. Therefore, the impact absorbing member of this configuration has the advantage that the rigidity can be adjusted by the bead portion without making manufacturing difficult.

[0020] As described above, according to the present invention, it is possible to provide an impact absorbing member that can absorb impacts applied to a vehicle from the side, which does not require processing of the door trim and can be easily manufactured.

[0021] FIG. 1(a) is a perspective view of an impact absorbing member according to one embodiment of the present invention, as seen from the top side, and FIG. 1(b) is a perspective view of the impact absorbing member as seen from the bottom side. FIG. 2(a) is a plan view of the impact absorbing member, FIG. 2(b) is a side view of the impact absorbing member, and FIG. 2(c) is a cross-sectional view taken along line A-A. FIG. 3 is a cross-sectional view taken along line B-B. FIG. 4 is an explanatory diagram showing the door trim from the inside of the vehicle. FIG. 5 is a load-displacement curve of the impact absorbing member. FIG. 6(a) is a schematic diagram of an impact absorbing member in an undeformed state, FIG. 6(b) is a schematic diagram of an impact absorbing member in the early stages of deformation, FIG. 6(c) is a schematic diagram of an impact absorbing member in the middle stages of deformation, and FIG. 6(d) is a schematic diagram of an impact absorbing member in the later stages of deformation.

[0022] Specific embodiments of the present invention will be described below with reference to the drawings. An impact absorbing member 1 of this embodiment is attached to a door trim 3 so as to be located between an outer panel 2 and the door trim 3 that constitute a vehicle door. The door trim 3 is attached to the outer panel 2. Hereinafter, the direction in which the outer panel 2 and the door trim 3 are separated from each other will be referred to as the width direction of the vehicle. In the width direction, the outer panel 2 side will be referred to as the outside, and the door trim 3 side will be referred to as the inside.

[0023] The impact absorbing member 1 includes a first box-shaped portion 10 , two second box-shaped portions 20 , a pair of beam plate portions 30 , and four mounting portions 40 .

[0024] The first box-shaped portion 10 is box-shaped and opens outward. More specifically, the first box-shaped portion 10 has a truncated quadrangular pyramid shape and includes a first bottom wall 11, a pair of first side walls 12, and a pair of second side walls 13. The first bottom wall 11 is flat and has a rectangular outer shape. The pair of first side walls 12 are flat and extend outward from a pair of opposing sides of the first bottom wall 11. The pair of second side walls 13 are flat and extend outward from a pair of other sides of the first bottom wall 11. The pair of first side walls 12 and the pair of second side walls 13 are inclined so as to move farther apart toward the opening (outward), and the area enclosed by the opening edge is larger than the area of ​​the first bottom wall 11. The first bottom wall 11 corresponds to the "bottom wall" in this invention.

[0025] Each of the two second box-shaped portions 20 has a box shape that opens inward. More specifically, each of the second box-shaped portions 20 includes a second bottom wall 21, a third side wall 22, a fourth side wall 23, and a pair of fifth side walls 24.

[0026] The second bottom wall 21 is flat and has a T-shaped exterior. The third side wall 22 extends inward from the long side of the horizontal bar of the T shape of the second bottom wall 21. A pair of fifth side walls 24 extend inward from each of the opposite ends of the horizontal bar of the T shape of the second bottom wall 21. The fourth side wall 23 extends inward from the remaining side of the outer periphery of the second bottom wall 21. As a result, both sides of the fourth side wall 23 are recessed, with the vertical bar of the T shape of the second bottom wall 21 between them.

[0027] The inner edge of the third side wall 22 is connected to the outer edge of the second side wall 13 of the first box-shaped portion 10. Here, the third side wall 22 is an extension of the second side wall 13. The protrusion length of the fifth side wall 24 from the second bottom wall 21 is approximately the same as that of the third side wall 22, but the fourth side wall 23 protrudes longer than the fifth side wall 24.

[0028] The pair of beam plate portions 30 are each flat and parallel to the first bottom wall 11, and extend in a bent manner from the open ends of the pair of first side walls 12. The inner end of the third side wall 22 is longer than the outer end of the second side wall 13, and the third side wall 22 protrudes from both sides of the second side wall 13 by that amount. The protruding length of the third side wall 22 is the same as the extending length of the beam plate portions 30. In each beam plate portion 30, both end edges in a direction perpendicular to the extending direction are joined to the third side wall 22. As a result, the pair of beam plate portions 30 each connects the two second box-shaped portions 20 in a beam-like manner along the open ends of the second side walls 13. The first box-shaped portion 10 is located inside the beam plate portions 30, and the second box-shaped portion 20 has a portion located outside the beam plate portions 30.

[0029] Two mounting portions 40 are provided in one second box-shaped portion 20. Each mounting portion 40 is a flat plate parallel to the second bottom wall 21, and has a mounting hole 41 formed therethrough. Each mounting portion 40 is located in the recessed portion of the fourth side wall 23, slightly outside the open end edge of the fourth side wall 23.

[0030] In the fourth side wall 23 of each of the two second box-shaped portions 20, the portion on the open end side (inner side) of the mounting portion 40 is referred to as a leg wall 23b. The impact absorbing member 1 has two leg walls 23b.

[0031] A plurality of bead portions 50 are formed on the first side wall 12, the second side wall 13, and the third side wall 22 that is continuous with the second side wall 13. Each bead portion 50 is a protrusion that protrudes toward the external space of the first box-shaped portion 10. The direction in which each bead portion 50 extends is from the first bottom wall 11 toward the opening edge of the first box-shaped portion 10. The bead portions 50 on the second side wall 13 and the bead portions 50 on the third side wall 22 are continuous. The protruding height of the bead portions 50 is constant along the entire length.

[0032] 3, the bead portion 50 has a shape in which the plate material constituting the first side wall 12, the second side wall 13, and the third side wall 22 is bent. Therefore, on the surface of each side wall opposite to the surface from which the bead portion 50 protrudes, a groove is formed at a position corresponding to the bead portion 50. The rigidity of each of the first side wall 12, the second side wall 13, and the third side wall 22 can be adjusted by changing the number of bead portions 50 and the protruding height (which is also the number and depth of the grooves).

[0033] Here, the case where the bead portion 50 protrudes toward the external space of the first box-shaped portion 10 and a groove is formed on the surface facing the internal space of the box is illustrated, but the opposite is also possible. That is, the bead portion may protrude toward the internal space of the box and a groove may be formed on the surface facing the external space of the box. Furthermore, one impact absorbing member may have both a bead portion protruding toward the external space of the box and a bead portion protruding toward the internal space, with grooves formed in corresponding positions on the surfaces opposite each other.

[0034] The impact absorbing member 1 of this embodiment can be formed by injection molding a thermoplastic resin.

[0035] The impact absorbing member 1 of this embodiment is attached to the door trim 3 via the attachment portion 40. As shown in FIG. 4 , the door trim 3 has an armrest 3a provided near the center in the vertical direction, and a door pocket 3b provided below the armrest 3a. The impact absorbing member 1 is attached to a location rearward of the door pocket 3b. In other words, the impact absorbing member 1 is attached so that the first box-shaped portion 10 is located to the side of the waist of an occupant seated in a vehicle seat.

[0036] Next, we will explain impact absorption by the impact absorbing member 1 of this embodiment. The impact absorbing member 1 is attached to the door trim 3 so that there is a gap between the first bottom wall 11 and the door trim 3, and there is a gap between the second bottom wall 21 and the outer panel 2 (see FIG. 6( a)).

[0037] When an inward impact acts on the outer panel 2 due to a side collision of the vehicle, the outer panel 2 moves inward and abuts against the second bottom wall 21 of the impact absorbing member 1. At that time, the outer panel 2, the impact absorbing member 1, and the door trim 3 move inward together, and the door trim 3 abuts against the waist of the occupant. Because the first box-shaped portion 10 is located to the side of the occupant's waist, the door trim 3 bends and bulges outward when it abuts against the waist, and the door trim 3 abuts against the first bottom wall 11.

[0038] The direction of the load acting between the occupant and the door due to an impact is relative. Therefore, the deformation process of the impact absorbing member 1 will be explained below using the results of a commonly used impact absorption simulation in which an impactor 4 (a dummy occupant) collides with the door trim 3. Note that here, the outer panel 2 and the door trim 3 are considered to move integrally as a rigid body. In Figures 6(a) to 6(d), the attachment portion between the impact absorbing member 1 and the door trim 3 is not shown.

[0039] When the impactor 4 is caused to collide with the door trim 3 from inside the vehicle, the door trim 3 curves and bulges outward, coming into contact with the first bottom wall 11 of the impact absorbing member 1. Then, the impactor 4 presses the impact absorbing member 1 outward via the door trim 3, causing the impact absorbing member 1 to move outward together with the door trim 3, and the two second bottom walls 21 come into contact with the outer panel 2. From this point on, a load acts on the impact absorbing member 1 in a direction that brings the first bottom wall 11 and the two second bottom walls 21 closer to each other.

[0040] As shown in FIG. 5 , the stages in which the impact absorbing member 1 absorbs the impact under this load can be broadly divided into an "initial stage," a "middle stage," and a "late stage" in accordance with the increase in the displacement of the impactor 4. In the initial stage, the first box-shaped portion 10 continues to receive the load while deforming. In the impact absorbing member 1, the load is received by one first box-shaped portion 10 and two second box-shaped portions 20. Therefore, the first box-shaped portion 10 receives a larger load per portion, and is therefore more susceptible to deformation than the second box-shaped portions 20. Therefore, in the initial stage, as shown in FIG. 6( b), the first side wall 12 and the second side wall 13 of the first box-shaped portion 10 begin to bend. Furthermore, each of the two leg walls 23 b also begins to bend. In this initial stage, the load increases substantially proportional to the displacement of the impactor 4.

[0041] In this way, when the first box-shaped portion 10 is subjected to a load, the first bottom wall 11 is in surface contact with the door trim 3, so the impact absorbing member 1 is less likely to slip relative to the door trim 3 compared to the prior art where a flat member is in linear contact with the door trim. This eliminates the need to provide a member on the door trim 3 to hold a part of the impact absorbing member 1.

[0042] Furthermore, in the first box-shaped portion 10, the pair of first side walls 12 and the pair of second side walls 13 are inclined so that they move farther apart as they extend outward. Therefore, when a load is applied in a direction that brings the first bottom wall 11 and the second bottom wall 21 closer together, each side wall is more likely to deform toward the exterior space of the box than toward the interior space of the box. This prevents the components of the first box-shaped portion 10 from interfering with each other on the opening side and providing resistance to deformation, allowing the first box-shaped portion 10 to deform as desired. Additionally, because a beam portion 30 is provided along the edge of the first side wall 12 on the opening side, the presence of this beam portion 30 effectively prevents the pair of second side walls 13 from deforming toward or away from each other on the opening side.

[0043] In the middle stage, the deformation of the first box-shaped portion 10 and the leg wall 23b progresses. As shown in Figure 6(c) , when the first side wall 12 and the second side wall 13 buckle, the buckled portions are deformed so as to be folded in association with the displacement of the impactor 4. During this deformation, the change in load is small relative to the increase in the displacement of the impactor 4.

[0044] As the deformation progresses further and reaches a later stage, the first box-shaped portion 10 becomes almost crushed, and the two second box-shaped portions 20 begin to deform, as shown in Figure 6(d). With the first box-shaped portion 10 almost crushed, the beam portion 30 begins to receive the load, and as the beam portion 30 receives the load, the deformation of the second box-shaped portion 20 progresses. At this stage, the load increases again as the displacement of the impactor 4 increases.

[0045] The two second box-shaped portions 20 are connected by two beam plate portions 30. In addition, the third side walls 22 of the two second box-shaped portions 20 are extensions of the second side walls 13, and are therefore inclined so as to move away from each other. These features prevent the two second box-shaped portions 20 from approaching each other and interfering with each other when the two second box-shaped portions 20 are deformed due to a load that moves the first bottom wall 11 and the second bottom wall 21 toward each other. Therefore, the progress of the deformation of the two second box-shaped portions 20 is not hindered by interference between the members.

[0046] As described above, according to the impact absorbing member 1 of this embodiment, the first box-shaped portion 10 (and leg wall 23b) and the second box-shaped portion 20 are deformed sequentially, thereby sufficiently absorbing the impact caused by a side collision with the vehicle door.

[0047] Furthermore, according to this embodiment, the first bottom wall 11 of the impact absorbing member 1 is less likely to slide relative to the door trim 3, and therefore, unlike the conventional technology in which a restricting piece is provided on the door trim, there is no need to process the door trim 3. Therefore, the impact absorbing member 1 can be attached to the door trim 3 with less effort and cost than in the past.

[0048] In the impact absorbing member 1, the rigidity of the first box-shaped portion 10 can be changed by varying the height of the first box-shaped portion 10, i.e., the distance from the first bottom wall 11 to the beam plate portion 30. This makes it possible to adjust the impact absorption until the first box-shaped portion 10 is almost crushed. Furthermore, by varying the distance from the first bottom wall 11 to the beam plate portion 30, it is possible to adjust the stroke at which the load is received until the final stage.

[0049] Furthermore, because the impact absorbing member 1 includes the bead portions 50, the rigidity of the first box-shaped portion 10 can be changed by adjusting the number of bead portions 50 and their protruding height, thereby adjusting the impact absorption until the first box-shaped portion 10 is almost crushed. In addition, the bead portions 50 prevent the first box-shaped portion 10, which initially receives a load, from deforming in a manner that causes it to collapse toward the interior or exterior space of the box. The bead portions 50 allow the first box-shaped portion 10 to undergo deformation that causes it to collapse due to compression when it receives an external force acting in the width direction of the vehicle due to a side collision.

[0050] In addition, in this embodiment, the bead portions 50 have a bent plate shape, which contributes to adjusting the surface rigidity of both the front and back surfaces of each of the first side wall 12, the second side wall 13, and the third side wall 22. Furthermore, in each side wall, the back surface of the portion where the bead portion 50 protrudes is a groove, so the bead portions 50 can be provided with less of an increase in weight of the impact absorbing member 1 compared to when no groove is provided.

[0051] Furthermore, since the impact absorbing member 1 has a shape formed by connecting three box-shaped parts (a first box-shaped part 10 and two second box-shaped parts 20), the structure of the mold for manufacturing it is simple and it can be manufactured easily.

[0052] In addition, the impact absorbing member 1 includes multiple bead portions 50. A shape in which a box-shaped portion includes bead portions requires a simpler mold structure for manufacturing than a shape in which a flat plate-shaped member includes ribs (Patent Document 1). Furthermore, the bead portions 50 of the impact absorbing member 1 are formed by bending a plate material. Therefore, the mold structure for manufacturing is simpler than a shape in which a flat plate-shaped rib protrudes from a flat plate-shaped member (Patent Document 1). Therefore, by providing the bead portions 50, the rigidity of the first box-shaped portion 10 can be adjusted without compromising the advantage of ease of manufacturing.

[0053] The present invention has been described above by citing preferred embodiments, but the present invention is not limited to the above embodiments, and various improvements and design changes are possible as described below, without departing from the spirit of the present invention.

[0054] For example, in the above embodiment, the bead portion 50 is provided on each of the first side wall 12, the second side wall 13, and the third side wall 22, but this is not limiting. The bead portion 50 may be provided on at least one of the side walls.

[0055] In the above embodiment, the shape of the first box-shaped portion 10 is a truncated quadrangular pyramid, but this is not limiting. The first box-shaped portion 10 may also be a rectangular parallelepiped (including a cube) that is open in one direction.

[0056] Furthermore, in the above embodiment, the third side wall 22 is an extension of the second side wall 13, but this is not limiting. The third side wall 22 may be inclined with respect to the extension of the second side wall 13.

Claims

1. An impact absorbing component that is installed between an outer panel of a vehicle and a door trim attached to the outer panel, comprising: a first box-shaped portion that is open in one direction; two second box-shaped portions that are box-shaped and open in the opposite direction to the first box-shaped portion and are connected to both sides of the first box-shaped portion; and two beam portions that are flat plates parallel to the bottom wall of the first box-shaped portion and connect the two second box-shaped portions at a position closer to the opening of the first box-shaped portion than the bottom wall.

2. The impact absorbing member according to claim 1, wherein the first box-shaped portion is a truncated quadrangular pyramid in which the area enclosed by the opening edge is larger than the area of ​​the bottom wall.

3. The impact absorbing member according to claim 1, characterized in that the first box-shaped portion has a plurality of bead portions that protrude from at least one of the outer surface or the inner surface and extend from the bottom wall toward the edge of the opening.

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