JP2009161028A - Shock-absorbing body for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shock absorbing body for a vehicle, exerting a stable shock-absorbing performance by deformation of a shock absorbing body being crushed by preventing the strength against load of part reduced in thickness in blow molding from being lowered. <P>SOLUTION: The shock absorbing body 1 has a hollow structure formed integrally by blow molding, and includes a body having a hollow portion, and a plurality of pairs of recessed ribs 6 and 7. Each pair of recessed ribs 6 and 7 has a fist wall 4 and a second wall 5, respectively, which are opposed to each other, and front ends of the walls formed by being recessed toward the other are joined with the corresponding recess on the opposing wall. In a portion of corner portions 12 and/or edge portions 14 of the wall face constituting the shock absorbing body 1, recessed notch portions 13 and 15 are formed along the contour of the corner portions 12 and the edge portions 14. The recessed notch portions 13 and 15 formed along the contour of the corner portions 12 and the edge portions 14 are formed to be notched toward the hollow portion. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention is applied to vehicle components such as doors, door trims or body side panels, roof panels, pillars, and bumpers (in particular, those that are interposed between the bumper fascia and the bumper beam to absorb the impact received by the bumper fascia). The present invention relates to a shock absorber for a vehicle for absorbing a shock from the outside such as a collision with an inner wall of a vehicle constituent member or a collision with another vehicle.

This type of impact absorber for vehicles has a hollow portion with a hollow double wall structure by blow molding a thermoplastic resin, and a concave rib is formed from the front wall and the back wall, and the tip portions of each other. JP-A-2004-149074 discloses a technique in which the two are joined and integrated to improve impact absorption. The vehicle shock absorber for which the elastic modulus was composed of a polypropylene resin of 5000kg ^/ cm ² ~2500kg ^/ cm 2 flexural is described in Japanese Patent No. 3313999.

Japanese Patent Laid-Open No. 2000-193008 discloses that a cylindrical impact energy absorbing member is formed with a notch or a notch shape as a breakage trigger to cause stable self-breakage. Furthermore, a hollow bag-shaped side impact collision pad for a vehicle made of blow molding, which bursts the entire pad by a stress concentration portion and absorbs collision energy, is described in Japanese Patent Application Laid-Open No. 2000-177518.
JP 2004-149074 A JP 2000-193008 A JP 2000-177518 A

  In a vehicle shock absorber having a blow-molded hollow double wall structure, such as the vehicle shock absorber described in Japanese Patent Application Laid-Open No. 2004-149074, in the process of absorbing energy due to the shock, The shock absorber, particularly the wall surface of the concave rib, is destroyed so as to be crushed. However, as the shock absorber is crushed, the air interposed in the hollow portion of the shock absorber is compressed, and the internal pressure rises, affecting the shock absorption characteristics. This influence generally causes variation in the load value, making it difficult to adjust the shock absorbing performance.

  By the way, in this type of vehicle shock absorber, the portion away from the corner (corner portion) and the parting line is thinned during the blow molding process, so the thinned portion is impacted. It is also pointed out that this can cause a significant reduction in shock absorption.

  Therefore, the present invention provides a blow molding by forming a concave portion having a shape extending over the corner or the edge at the corner or the edge of the wall surface constituting the shock absorber and the both thereof. An object of the present invention is to provide a vehicle shock absorber capable of demonstrating a stable shock absorption performance by eliminating the strength reduction with respect to the load of the thinned portion and smashing and deforming the shock absorber. It is.

  In order to achieve the above object, a shock absorber for a vehicle according to claim 1 of the present invention is for a vehicle made of a thermoplastic resin for absorbing a shock from the inside or the outside of the vehicle by being installed in a vehicle constituent member. In the shock absorber, the shock absorber is a hollow structure integrally formed by blow molding, and the main body having a hollow portion and the first wall and the second wall of the main body facing each other face each other. It has a plurality of concave ribs that are indented and joined to each other's tip, and has corners or edges at the corners and / or edges of the wall that constitutes the shock absorber. In this way, a concave portion having a shape extending to the periphery thereof is formed.

  According to a second aspect of the present invention, there is provided a vehicular shock absorber according to the first aspect of the present invention, wherein the recessed portion having a shape extending to the periphery of the corner portion or the edge portion is cut into the hollow portion. It is characterized by being formed.

  According to a third aspect of the present invention, there is provided the vehicle impact absorber according to the first or second aspect, wherein the recessed portion having a shape extending around the corner portion or the edge portion extends linearly toward the hollow portion. It is formed in the shape of a cut and a rib is formed in a crescent shape.

  According to the vehicle shock absorber according to the present invention, the corners or edges of the wall surface constituting the shock absorber and both of them are provided with a recessed portion having a shape extending to the periphery of the corner or edge. By forming, an effect can be obtained in which the strength reduction with respect to the load of the thinned portion by blow molding is eliminated, and the stable shock absorbing performance due to the impact absorber being crushed and deformed can be exhibited.

  FIG. 1 is a perspective view of a vehicle shock absorber according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line AA of FIG. 1, and FIG. 3 is a vehicle shock absorber according to another embodiment of the present invention. FIG. 4 is a perspective view of a vehicle shock absorber according to still another embodiment of the present invention, and FIG. 5 is a graph showing characteristics of the vehicle shock absorber according to the embodiment of the present invention. It is.

  1 and 2, reference numeral 1 denotes an impact absorber. This shock absorber 1 is formed by blow molding a thermoplastic plastic into a hollow shape, 2 is a hollow portion, 3 is a peripheral wall surface, 4 is a first wall, and 5 is a second wall. There are many pairs of concave ribs 6 and 7 formed by recessing both the first wall 4 and the second wall 5 forming the hollow shock absorber 1 toward the other, and these The tip portions of the concave ribs 6 and 7 are in contact with each other to form a welding surface 8. A plurality of attachment pieces 10 are formed from the parting line 9 on the peripheral wall 3 of the shock absorber 1, and 11 is an attachment hole.

  In the shock absorber 1, a recessed portion 13 having a shape extending over the corner 12 and extending around the corner 12 is formed in the corner 12 of the wall surface constituting the shock absorber 1. A concave portion 15 having a shape extending over the edge 14 and extending to the periphery thereof is also formed on the edge 14 of the wall surface constituting the wall. The concave portions 13 and 15 having a shape extending to the corner 12 or the edge 14 and extending to the periphery thereof are formed in a cut shape having a steep valley shape toward the hollow portion.

  Further, the line of the edge of the recessed portion with each wall is preferably linear rather than arcuate. However, the boundary between the first wall or the second wall and the rib is preferably a slightly smooth arc. The wall surface forming the concave valley is preferably flat. The effect of providing the recessed portion is more prominent at the corner than the edge, and it is further desirable to provide the recessed portion at a portion where the angle of the corner is 120 degrees or less, preferably 90 degrees or less.

  In the shock absorber 1, since the recessed portion 13 is formed in the corner portion 12 having a large blow ratio, an effect of suppressing a decrease in strength against a load can be obtained even if the portion becomes thin. Further, the parting line 9 is basically provided at a substantially intermediate line between the first wall 5 and the second wall 5 of the peripheral wall 3, and is inclined gently in the direction in which the mounting piece 10 is provided to coincide with the second wall 5. It is formed as follows. For this reason, the blow ratio of the edge 14 on the side where the mounting piece 10 is provided becomes large and thin. However, since the edge 14 is formed with a plurality of recessed portions 15, the load is reduced even if the portion becomes thin. The strength reduction with respect to can be suppressed.

  The recess 13 having a shape extending over the corner 12 of the shock absorber 1 and the periphery thereof, and the recess 15 extending over the periphery of the edge 14 have a maximum opening width a of 9 to 20 mm and a maximum depth b. When the thickness is about 5 to 20 mm, it is particularly effective in suppressing a decrease in strength against a load.

  The shock absorber 1 of the present invention can be in the embodiment shown in FIGS. In the embodiment shown in FIG. 3, the concave portion 13 having a shape extending over the corner 12 and extending around the corner 12 on both the first wall 4 side and the second wall 5 side is formed. It does not have a mounting piece. In the embodiment shown in FIG. 4, the parting line 9 is formed on the intermediate width line of the peripheral wall 3, and the attachment piece 10 is formed in the direction from the parting line 9 to the second wall 5. It is what has been.

The impact absorber for vehicles according to the present invention has a high mechanical altitude such as rigidity, such as polyolefin resin such as polyethylene and polypropylene, styrene resin such as polystyrene and ABS resin, polyester resin such as polyethylene terephthalate, and polyamide. Consists of resin. In particular, polypropylene, ABS resin, high-impact polystyrene (HIPS), and polyphenylene ether resin are preferable from the viewpoint of suitably functioning the rupture-inducing portion, and a blend or polymer alloy thereof is preferable. Is 10000 kg / cm ² or more, and the Izod impact value at room temperature is preferably in the range of 35 kg / cm ² or less.

  The graph of FIG. 5 has shown notionally the result of having measured the displacement (change of a compressive strain) with respect to the compressive load of the shock absorber 1 which concerns on this invention, and a continuous line is a characteristic by the embodiment of this invention, and is a broken line Is an aspect of the conventional example. In other words, in the shock absorber 1 according to the present invention, the concave portion 13 having a shape extending over the corner 12 and surrounding the corner 12 is formed at the corner 12 of the wall constituting the shock absorber 1. In addition, since the recessed portion 15 is formed on the edge portion 14 of the wall surface constituting the shock absorber 1 so as to reach the periphery of the edge portion 14, the portion is formed by blow molding. In spite of being thin, as a whole, stable shock absorbing performance is exhibited from the beginning, whereas in the conventional shock absorber having no concave portions 13 and 15 as described above, as shown by the broken line, As the absorber is crushed, it appears as a variation in the value of the load, and it is difficult to adjust the shock absorbing performance.

  According to the shock absorber according to the present invention, the blow ratio becomes high not only when the parting line 9 is in the middle line of the peripheral wall 3 but also when the parting line is biased to one side. By forming a recess in the thinned part, it is possible to effectively suppress a decrease in strength against the load, so there are few restrictions on the shape on blow molding, and this type of shock absorber is diverse. It becomes possible to blow-mold the shape.

  The shock absorber 1 according to the present invention is installed in a vehicle component such as a door of an automobile, a door trim or a body side panel, a roof panel, a pillar, a bumper, etc., and greatly improves the shock absorption of those parts. Can greatly contribute to improving the safety of automobiles.

1 is a perspective view of a vehicle shock absorber according to an embodiment of the present invention. It is AA sectional drawing of FIG. It is a perspective view of the shock absorber for vehicles concerning other embodiments of the present invention. It is a perspective view of the shock absorber for vehicles concerning other embodiments of the present invention. It is a graph which shows the characteristic of the shock absorber for vehicles concerning one embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Shock absorber 2 Hollow part 3 Perimeter wall surface 4 First wall 5 Second wall 6, 7 Concave rib 8 Welding surface 9 Parting line 10 Attachment piece 11 Attachment hole 12 Corner part 13 Concave part 14 Edge part 15 Concave part

Claims (3)

In a vehicle impact absorber made of thermoplastic resin for absorbing impact from inside or outside the vehicle by being installed in the vehicle component,
The shock absorber is a hollow structure integrally formed by blow molding, and a main body having a hollow portion and the first wall and the second wall facing each other are recessed toward each other, and each other is depressed. While having a plurality of concave ribs that make a pair with the tip joined,
A shock absorber for a vehicle characterized in that a corner or edge portion of the wall surface constituting the shock absorber and a concave portion having a shape extending to the periphery of the corner portion or the edge portion is formed at the corner portion or the edge portion. body.   2. The impact absorber for a vehicle according to claim 1, wherein the recessed portion having a shape extending to the periphery of the corner portion or the edge portion is formed in a cut shape toward the hollow portion.   The recessed portion having a shape extending to the periphery of the corner portion or the edge portion is formed in a straight cut shape toward the hollow portion, and a rib is formed in a crescent shape. The impact absorber for vehicles according to 1 or 2.

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