JP2005022597A - Shock absorbing structure of vehicle and method of manufacturing shock absorbing structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shock absorbing structure for a vehicle composed of a small number of components. <P>SOLUTION: The shock absorbing structure 10 of the vehicle is equipped with a bumper 16 mounted between ends of side members 14 installed on the right and left of the vehicle and shock absorption parts 18 interposed between the ends of the side members 14 and the bumper 16 and to buckle at collision for absorbing shocks, wherein the bumper 16 and the shock absorption parts 18 are formed in a single structure having a honeycomb form in a horizontal section. By the single structure of the parts 16 and 18, the number of components can be decreased compared with a conventional arrangement. Shock absorption at collision can be conducted at multiple stages by selecting the honeycomb form as appropriate. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a shock absorbing structure for a vehicle, particularly a front portion of the vehicle.

  When a vehicle such as an automobile collides with another object, a bumper is provided at the front of the vehicle in order to absorb and mitigate the impact. For example, as described in Patent Document 1, a conventional general bumper includes a bumper reinforcement that is placed between front end portions of left and right side members, a bumper cover disposed in front of the bumper reinforcement, and a bumper cover and a bumper. It consists of an absorber placed between the reinforcements. The bumper reinforcement is a hollow body made of a lightweight aluminum alloy, a steel plate, or the like, and is fixed to a side member via a bumper arm. The bumper cover and the absorber are made of synthetic resin, and in particular, the absorber is made of foamed resin.

In recent years, an impact absorbing member called a crash box tends to be disposed between the bumper reinforcement and the side member in order to increase the amount of absorption of impact energy. A crash box is a hollow structure that can buckle and deform by receiving a strong impact, thereby absorbing impact energy.
Japanese Patent Laid-Open No. 9-76841

  Although the conventional shock absorbing structure composed of the bumper and the crash box as described above is satisfactory in performance, it has a problem that the number of parts is large. In other words, in addition to the bumper itself consisting of multiple parts, the crash box is handled as an independent part separate from the bumper, so the total number of parts of the shock absorbing structure is considerably large. Yes. As a result, naturally, the production process and the assembly process were also increased.

  Accordingly, an object of the present invention is to provide an impact absorbing structure having a small number of parts.

  In order to achieve the above-described object, the invention according to claim 1 includes a bumper portion provided between the end portions of the side members provided on the left and right sides of the vehicle, and the end portion of the side member and the bumper portion An impact absorbing structure for a vehicle having an impact absorbing portion that is interposed between and absorbs an impact by buckling deformation at the time of a vehicle collision, wherein the bumper portion and the impact absorbing portion are integrated into a honeycomb shape in a horizontal section It is characterized by being a product.

  In such a configuration, the number of parts can be reduced as compared with the conventional configuration by integrating the bumper portion and the shock absorbing portion. In addition, by appropriately selecting the honeycomb shape, it is possible to perform shock absorption at the time of collision in multiple stages. The integrated product means an integrated product in which the bumper part and the shock absorbing part cannot be separated, and does not include a structure in which the parts are detachably fastened with bolts or the like. The honeycomb shape includes not only a hexagon but also a triangle, a quadrangle, a sine waveform, a double waveform, and the like.

  In addition, it is effective that the left and right side plate portions of the shock absorbing portion are provided so that the distance between the two is widened from the end portion of the side member toward the bumper portion.

  In this configuration, the area of the boundary portion between the panel main body portion and the shock absorbing portion is increased. As a result, the panel body can receive a load due to impact over a wide area, and the efficiency of the collision energy absorption characteristic can be increased.

  The present invention also relates to a method for manufacturing the shock absorbing structure. According to a third aspect of the present invention, there is provided a method of manufacturing an impact absorbing structure according to the present invention, in which an integrated product of the bumper portion and the impact absorbing portion is formed by an extrusion method, and then the extruded product is formed. It is characterized by being manufactured by cutting.

  According to the first aspect of the present invention, since the shock absorbing structure provided at the front or rear of the vehicle is an integrated product instead of the conventional bumper or crash box, the number of parts is reduced, and the shock absorbing structure is reduced. If only the manufacturing process of the body itself is used, the manufacturing process of the entire vehicle is reduced and the production efficiency is improved.

  Further, when the shock absorbing structure collides with the obstacle, it can be expected that the damaged portion becomes one place of the shock absorbing structure, and repair is facilitated.

  Furthermore, the impact at the time of collision can be absorbed in stages, the impact energy absorption characteristics can be improved, and the demand for short overhang can be met.

  In addition, according to the method for manufacturing the shock absorbing structure according to claim 3, the trouble of welding the plate material becomes unnecessary. In particular, in the past, bumper reinforcement (corresponding to the bumper part) and crash box (corresponding to the shock absorbing part) are manufactured by bending and welding a thin steel plate, and there are many parts, Although the number of manufacturing steps is increased, such a problem does not occur in the method of the present invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the figure, the same reference numerals are used for the same or corresponding parts.

  FIG. 1 is a plan view schematically showing an embodiment of an impact absorbing structure according to the present invention, and FIG. 2A is a cross-sectional view taken along the line II-II in FIG. The vehicle to which the shock absorbing structure according to the present embodiment is applied is a general passenger car. Further, in the present specification and the appended claims, the terms “horizontal” and “vertical” are used in a state where the vehicle is placed on a horizontal plane, and the forward direction when the vehicle is moving forward is defined as “forward”. “,” “Rear,” “left,” “right,” etc.

  As shown in FIG. 1 and FIG. 2A, the shock absorbing structure 10 according to the present embodiment is provided at the front end portions of the left and right side members 14 constituting the body frame of the vehicle 12. The shock absorbing structure 10 includes a bumper portion 16 disposed horizontally between the left and right side members 14, and a shock absorbing portion 18 disposed between the bumper portion 16 and the front end portion of each side member 14. It is an integrated product made of lightweight aluminum alloy. As will be described in detail below, this is manufactured from an extruded product obtained by an extrusion method.

  The bumper portion 16 corresponds to the bumper reinforcement in the conventional configuration, and has a pair of long front and rear horizontal plate portions 20 and 22 that are arranged at a predetermined interval in the front and rear direction and extend in the vehicle width direction. Yes. Further, an intermediate horizontal plate portion 24 having the same shape as these is disposed between the front and rear horizontal plate portions 20 and 22. Short vertical plate portions 26, 28 extending in the vehicle front-rear direction are provided between the front horizontal plate portion 20 and the intermediate horizontal plate portion 24 and between the intermediate horizontal plate portion 24 and the rear horizontal plate portion 22. A plurality of horizontal plate portions 20, 24; 24, 22 which are arranged at predetermined intervals and adjacent to each other are connected to each other. The surfaces of the horizontal plate portions 20, 22, 24 and the vertical plate portions 26, 28 extend in a substantially vertical direction. When the bumper portion 16 is horizontally cut, the horizontal cross-sectional shape is a rectangular honeycomb shape. ing.

  The shock absorbing portion 18 extends rearward from the rear surface of the rear side plate portion 22 of the bumper portion 16, and a part of the rear side plate portion 22 of the bumper portion 16, the left and right side plate portions 30, and the side member 14. The rear side plate portion 32 is disposed adjacent to the front end portion. The distance between the rear ends of the left and right side plate portions 30, that is, the length of the rear side plate portion 32 is substantially the same as the width of the side member 14. Further, the left and right side plate portions 30 are arranged obliquely so that the distance between them gradually increases toward the front of the vehicle. An intermediate horizontal plate portion 34 extending in the vehicle width direction is disposed between the rear horizontal plate portion 22 of the bumper portion 16 and the rear horizontal plate portion 32 on the side member 14 side. Further, a pair of vertical plate portions 36 extend from the intermediate point between the front ends of the left and right side plate portions 30 to the rear end of each side plate portion 30 so as to penetrate the intermediate horizontal plate portion 34. The surfaces of the plate portions 30, 32, 34, and 36 in the shock absorbing portion 18 also extend in a substantially vertical direction like the bumper portion 16, and the horizontal sectional shape thereof is a trapezoidal shape and a triangular honeycomb shape.

  Further, a fixed portion 38 extends rearward from each of the left and right end portions of the rear side plate portion 32 of the shock absorbing portion 18. The interval between the fixing portions 38 is equal to the width of the side member 14. In the present embodiment, since this portion is fixed to the side member 14 by the bolt and nut 40, each fixing portion 38 is formed with a bolt hole (not shown).

  In the present embodiment, the shock absorbing structure 10 having the above configuration is manufactured as follows.

  First, a so-called deformed extruded product 42 as shown in FIG. 3A is manufactured using an extruder. The extrusion method used in this step may be a general one, and the manufactured extruded product 42 has a cross-sectional shape orthogonal to the extrusion direction that matches the shape shown in FIG. Further, the length of the extruded product 42 in the extrusion direction is sufficiently longer than the height of the shock absorbing structure 10.

  Next, the extruded product 42 is cut at a position indicated by a dotted line in FIG. What was cut out in this way (indicated by reference numeral 10A in FIG. 3B) generally coincides with the shock absorbing structure 10 shown in FIGS.

  Thereafter, a bolt hole 44 is formed in the portion 38A corresponding to the fixed portion, and the shock absorbing structure is formed by chamfering the corner portion, performing other surface processing, or finishing processing such as welding of other parts as necessary. 10 is completed.

  According to this manufacturing method, the impact-absorbing structure 10 can be obtained by only three steps of the extrusion molding process, the cutting process, and the finishing process, and after performing the extrusion process once, the cutting process and the finishing process are performed. A plurality of shock absorbing structures 10 can be obtained only by repeating the steps. This method greatly simplifies the manufacturing process as compared with a conventional configuration in which bumper reinforcement and a crash box are separately manufactured and connected.

  When an impact is applied from the front in a state where the shock absorbing structure 10 manufactured as described above is fixed to the front end portion of the side member 14 using the bolts and nuts 40, the front side of the bumper portion 16 is first caused by the impact. The vertical plate portion 26 between the horizontal plate portion 20 and the intermediate horizontal plate portion 24 mainly buckles and absorbs the impact. When the impact energy is large and the impact cannot be absorbed by the buckling deformation by the vertical plate portion 26, the vertical plate portion 28 between the intermediate horizontal plate portion 24 and the rear side horizontal plate portion 22 is mainly used. It buckles and deforms, thereby absorbing the impact. Now, the rear part of the bumper part 16 (that is, the part composed of the intermediate horizontal plate part 24, the rear side horizontal plate part 22 and the vertical plate part 28 therebetween) has the same shock absorbing performance as that of the conventional bumper reinforcement. In this case, the front portion of the bumper portion 16 (that is, a portion including the front side horizontal plate portion 20, the intermediate horizontal plate portion 24 and the vertical plate portion 26 therebetween) is a portion corresponding to an absorber in a conventional bumper. . Therefore, in the configuration of the present embodiment, it is possible to omit the absorber and attach a bumper cover (not shown) made of synthetic resin so as to cover the front surface of the bumper portion 16. This also leads to a reduction in the number of parts.

  When the impact energy from the front of the vehicle is larger, the side plate portion 30 and the vertical plate portion 36 constituting the impact absorbing portion 18 are mainly buckled and deformed. Also in this case, the front portion of the intermediate horizontal plate portion 34 is deformed first, and if the impact energy cannot be absorbed, the rear portion is deformed and the impact is absorbed stepwise.

  In the present embodiment, as described above, shock absorption is performed in multiple stages. The deformation and progress of each part of the shock absorbing structure 10 at that time is shown in FIG. It is a graph of deformation amount. Note that the graph of FIG. 2B is a graph when the side member 14 is a non-moving body. As understood from FIG. 2, when an impact (load) is applied from the front, deformation (collapse) occurs from the front part of the shock absorbing structure 10, and the generated load maintains a peak for each part, and then It will gradually progress to the rear part. As described above, the impact can be absorbed in multiple stages, and the impact energy absorption characteristics are improved. As a result, it is possible to meet the demand for shortening the FR overhang (short overhang) in the vehicle design.

  In addition, since the side plate part 30 in the shock absorbing part 18 is attached obliquely so as to be widened forward, the area for supporting the load applied to the bumper part 16 is increased, and the impact energy absorption characteristics are further improved. Become.

  As mentioned above, although preferred embodiment of this invention was described in detail, it cannot be overemphasized that this invention is not limited to the said embodiment.

  For example, in the above embodiment, a shock absorbing structure is manufactured using a lightweight aluminum alloy, but the material is appropriately selected according to the required shock absorbing performance, and steel or other metals, or It may be a synthetic resin. When it is made of synthetic resin, it can be integrated with the bumper cover.

  Further, depending on the required shock absorbing performance, the shape of the shock absorbing structure, particularly the honeycomb shape of the horizontal section, can be appropriately changed.

  Furthermore, the method of integrating the shock absorbing structure is not limited to the method using the above-described extrusion method, and an injection molding method or the like can be used.

  Moreover, in the said embodiment, although the fastening means of the impact-absorbing structure 10 and the side member 14 is said to be bolt fastening, it is not restricted to this, For example, the function of this invention is impaired at the time of impact absorption like welding coupling | bonding. Any means may be used if it is not.

  Furthermore, in the above embodiment, the shock absorbing structure is provided at the front of the vehicle, but a similar shock absorbing structure may be provided at the rear of the vehicle.

  The present invention can be applied not only to passenger cars but also to special vehicles such as trucks and buses and other vehicles in general.

It is a schematic plan view which shows one Embodiment of the impact-absorbing structure by this invention. (A) is a schematic sectional drawing along the II-II line | wire of FIG. 1, (b) contrasts (a) with the relationship between the load and deformation amount when an impact is applied to the shock absorbing structure from the front. It is a graph shown. It is a schematic explanatory drawing which shows the manufacturing process of the impact-absorbing structure shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Shock absorption structure 12 ... Vehicle 14 ... Side member 16 ... Bumper part 18 ... Shock absorption part 38 ... Fixing part 40 ... Bolt and nut 42 ... Extrusion product 44 ... Bolt hole

Claims (3)

  Bumper portion provided between end portions of side members provided on both left and right sides of the vehicle, and buckling deformation at the time of collision of the vehicle provided between the end portion of the side member and the bumper portion. An impact absorbing structure for a vehicle comprising an impact absorbing portion for absorbing an impact, wherein the bumper portion and the impact absorbing portion are an integrated product having a honeycomb-shaped horizontal cross section.   2. The vehicle impact according to claim 1, wherein the left and right side plate portions of the shock absorbing portion are provided such that a distance between the left and right side plate portions is widened from the end portion of the side member toward the bumper portion. Absorbent structure. Bumper portion provided between end portions of side members provided on both left and right sides of the vehicle, and buckling deformation at the time of collision of the vehicle provided between the end portion of the side member and the bumper portion. In the method of manufacturing a shock absorbing structure for a vehicle comprising a shock absorbing portion that absorbs shock and the bumper portion and the shock absorbing portion are an integral product having a honeycomb-shaped horizontal cross section,
A method for manufacturing a shock absorbing structure for a vehicle, wherein the integrated product is manufactured by forming an extruded product by an extrusion method and then cutting the extruded product.

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