JP2005132303A - Impact absorption element for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an impact absorption element for a vehicle capable of ensuring required impact absorption performance even when the thickness of the impact absorption body is restricted, excellent in the impact absorption performance, in particular, immediately after the impact is applied thereto and capable of maintaining the required impact absorption performance over a wide range of from high temperatures to low temperatures. <P>SOLUTION: The impact absorption element 1 for the vehicle is a hollow shape molded by blow-molding thermoplastic resin. A plurality of pairs of recessed ribs 6, 7 having welding surfaces 8 of which distal ends are welded/integrated with each other are formed on a second wall 5 opposed to a first wall 4 of the impact absorption element 1. Plate-like ribs 9, 10 projected from the first wall 4 and the second wall 5 to the hollow part 3 side and adjacent to wall surfaces of the recessed ribs 6, 7 are formed. Reinforcement core materials 16, 17 are buried in the plate-like ribs 9, 10. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention absorbs external impacts such as a collision between a crew member and an inner wall of a vehicle component member by being installed in a vehicle component member, for example, a door or a body side panel, or a collision with another vehicle. The present invention relates to a vehicle impact absorber.

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-2002-187508 discloses a technique in which the two are joined together 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.

In addition, a vehicle duct having a shock absorbing property in which a concave rib and a plate-like rib are formed is disclosed in Japanese Patent Laid-Open No. 2000-193057 and Japanese Patent Laid-Open No. 2001-239573. JP-A-2001-34156 further describes a bumper rain reinforcement having a concave rib and a plate-like rib in Japanese Patent No. 2714567.
JP 2002-187508 A Japanese Patent No. 33133999 JP 2000-193057 A JP 2001-239573 A JP 2001-34156 A Japanese Patent No. 2714567

  Like the vehicle shock absorber described in the above-mentioned JP-A-2002-187508, concave ribs are formed from the front wall and the back wall of a hollow double wall structure made of a thermoplastic resin, and the tips of each other are formed. If the thickness of the shock absorber is sufficient, the required amount of shock absorption can be secured if the thickness of the shock absorber is sufficient. Improving shock absorption performance immediately after impact is required.

Also, as in the vehicular shock absorber described in the patent No. 3313999 publication, the apparatus having the flexural modulus was composed of a polypropylene resin of ^{5000kg / cm 2 ~25000kg / cm 2} , 60 ℃ ~ The stress change at the time of impact absorption at −15 ° C. is large, and the impact absorption performance changes depending on the temperature of the outside air. That is, based on the load stress at normal temperature when the compressive strain of the shock absorber made of polypropylene resin is 50%, the rate of change in stress is 21% when the temperature of the outside air is −15 ° C., and the temperature of the outside air is 60%. At the time of ° C., the stress change rate is −34%.

  In this type of vehicle shock absorber, it is desirable that the stress change rate is within ± 10% in the range of 60 ° C. to −15 ° C. with respect to compressive strain at normal temperature. Improvement of the temperature dependence of was desired.

  In view of this, the present invention provides a welded surface in which the tip portions are welded and integrated with each other on the second wall facing the first wall of the hollow vehicle impact absorber formed by blow molding of thermoplastic. A plurality of a pair of concave ribs, and at least one of the first wall and the second wall projecting from one of the first wall and the second wall toward the hollow portion, and a reinforcing core material is embedded adjacent to the wall surface of the concave rib. Even if there are restrictions, it is possible to ensure the required shock absorption performance, especially excellent shock absorption performance immediately after the impact is applied, and to maintain the required shock absorption performance over a wide range from high temperature to low temperature An object of the present invention is to provide a vehicle shock absorber.

  In order to achieve the above object, a vehicle impact absorber according to claim 1 of the present invention is a hollow vehicle impact absorber for absorbing impact from the inside or outside by being installed in a vehicle component. The vehicle impact absorber is formed into a hollow shape by blow molding a thermoplastic, and has a first wall and a second wall facing each other with a space therebetween, A plurality of a pair of concave ribs, each of which is formed by recessing one wall toward the second wall facing each other and recessing the second wall toward the first wall facing each other, including one concave rib and the other concave rib. Each of the concave ribs and the other concave rib has a welded surface in which the respective distal end portions are welded and integrated, and protrudes from at least one of the first wall or the second wall toward the hollow portion and is formed of the concave rib. Reinforced core material is buried adjacent to the wall And it is characterized in that is.

  According to a second aspect of the present invention, there is provided the vehicle impact absorber according to the first aspect, wherein the height (b) from the first wall of the one concave rib to the weld surface is 15.0 to 35.0 mm. The height (c) from the second wall of the other concave rib to the welding surface is formed to be 15.0 to 35.0 mm, and the distance (a) between the first wall and the second wall is 30.0 to 70.70. It is characterized by being formed to 0 mm.

  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 pair of plate-like ribs each projecting the first wall and the second wall toward the hollow portion side connect the concave ribs. And having a welded portion in which opposing ends of the pair of plate-like ribs are welded and integrated, and a reinforcing core material is embedded in at least one of the pair of plate-like ribs.

  According to a fourth aspect of the present invention, there is provided the vehicle impact absorber according to the first, second, or third aspect, wherein the concave ribs formed on the first wall and the second wall are substantially cylindrical, and the first wall and the second wall. Has a substantially circular opening having a diameter (d) of 15.0 to 30.0 mm due to the concave rib, and a reinforcing core material is embedded in the concave rib from the opening.

  According to a fifth aspect of the present invention, there is provided the vehicle impact absorber according to the first, second, third, or fourth aspect, wherein the insert member is made of the same thermoplastic material as the thermoplastic constituting the vehicle impact absorber. It is characterized by.

  According to the shock absorber for a vehicle according to the present invention, the distal ends of the shock absorber are integrated with each other on the second wall facing the first wall of the hollow shock absorber formed by blow-molding thermoplastic plastic. By forming a plurality of a pair of concave ribs having a welding surface, and projecting from at least one of the first wall or the second wall to the hollow portion side and burying a reinforcing core material adjacent to the wall surface of the concave rib, Even if the thickness of the shock absorber is limited, the required shock absorption performance can be ensured. Especially, the shock absorption performance immediately after the impact is applied is excellent, and the required shock absorption performance over a wide range from high temperature to low temperature. The effect that can be maintained is obtained.

  FIG. 1 is a perspective view showing a vehicle shock absorber according to a first embodiment of the present invention in a cutaway state, FIG. 2 is a plan view, FIG. 3 is a cross-sectional view taken along the line AA in FIG. -B sectional view, FIG. 5 is a partial perspective view, FIG. 6 is a perspective view showing a vehicle shock absorber according to the second embodiment of the present invention, and FIG. 7 is a plan view, FIG. 6 is a cross-sectional view taken along the line CC in FIG. 6, FIG. 9 is a graph showing the displacement of the vehicle shock absorber according to the present invention with respect to the compression load, and FIG. 10 is a blow molding of the shock absorber according to the first and second embodiments. FIG. 11 is a cross-sectional view showing a state in which the mold is clamped, FIG. 12 is a perspective view showing a vehicle shock absorber according to a third embodiment of the present invention, and FIG. 13 is a partial perspective view of the same. 14 and FIG. 14 are partial cross-sectional views showing a fourth embodiment of the present invention, and FIG. 15 is a block diagram of a shock absorber for a vehicle according to the third embodiment of the present invention. FIG. 16 is a cross-sectional view of the mold clamped state, FIG. 17 is a cross-sectional view of the mold open state after blow molding, and FIG. 18 is a cross-sectional view of the vehicle shock absorber according to the present invention. FIG. 19 is a cross-sectional view of the above, FIG. 19 is a cross-sectional view of the same, FIG. 20 is a cross-sectional view of a state in which the vehicle shock absorber according to the present invention is internally installed in the rear pillar of an automobile, and FIG. It is a rear view of the rear bumper which installed the shock absorber for vehicles which concerns.

  1 to 5, reference numeral 1 denotes a vehicle shock absorber. This vehicle impact 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. . It has many concave ribs 6 and 7 forming a pair formed by recessing both the first wall 4 and the second wall 5 forming the hollow vehicle shock absorber 1 toward the other. The tip portions of the concave ribs 6 and 7 are in contact with each other to form a welding surface 8. Plate ribs 9 are formed on the first wall 4 so as to connect the concave ribs 6, and plate ribs 10 are formed on the second wall 5 so as to connect the concave ribs 7. These plate-like ribs 9 and 10 are opposed to each other, and the opposite end portions are welded and integrated. 11 is the welding surface.

  The height b from the first wall 4 of the concave rib 6 to the welding surface 8 is 15.0 to 35.0 mm, and the height c from the second wall 5 of the concave rib 7 to the welding surface 8 is 15.0. It is formed to ˜35.0 mm. The distance a between the first wall 4 and the second wall 5 is 30.0 to 70.0 mm. The concave ribs 6 and 7 formed on the first wall 4 and the second wall 5 are substantially cylindrical, and the first wall 4 and the second wall 5 have a diameter d of 15.0 due to the concave ribs 6 and 7. It has substantially circular apertures 12 and 13 of ˜30.0 mm. The width e of the welding surface 11 of the concave ribs 6 and 6 is 5.0 to 15.0 mm, which is smaller than the apertures 12 and 13, and the concave ribs 6 and 7 are cup-shaped.

The vehicle impact absorber 1 is made of a polyolefin resin such as polyethylene or polypropylene. Further, an amorphous resin such as polystyrene resin or polyphenylene ether resin can be appropriately blended, and an Izod impact value at room temperature is 15 to 40 kg / cm ² .

  The plate-like ribs 9 and 10 formed on the first wall 4 and the second wall 5 are open to the respective wall surfaces. The plate-like ribs 9 and 10 have a reinforcing core 16 through their respective openings 14 and 15. , 17 are buried. The reinforcing cores 16 and 17 are made of the same material as that of the vehicle shock absorber 1, and the same material polypropylene resin is preferable from the viewpoint of resource reuse after disposal. However, the reinforcing cores 16 and 17 are not necessarily limited to the same material as that of the vehicle impact absorber 1 and may be made of metal, for example.

  As shown in FIGS. 6 to 8, the first wall 4 of the vehicle impact absorber 1 may be formed with a groove 31 in a direction perpendicular to the plate-like ribs 9 and 10. The depth g is 3.0 to 8.0 mm. The concave strip 31 may be formed not on the first wall 4 but on the second wall 5, or on both the first wall 4 and the second wall 5.

  The graph shows the result of measuring the displacement (change in compression strain) with respect to the compression load. A solid line and a broken line indicate displacements of the vehicle impact absorber having no pair of reinforcing cores, a vehicle impact absorber having a pair of concave ribs and a pair of reinforcing cores, respectively, with respect to a compressive load.

  According to the vehicle impact absorber 1 of the present invention, as shown by the solid line in FIG. 9, the displacement when the impact is applied shows the initial maximum stress in the vicinity of 5.00 mm, whereas there is no reinforcing core material. In the prior art, the initial maximum stress is exhibited after the stress increases gently until the displacement reaches 17.00 mm. From this, it is clear that in the vehicle impact absorber 1 according to the present invention, the impact absorbing performance immediately after the impact is applied is remarkably improved.

  In this way, in a vehicle shock absorber without a pair of reinforcing cores, the displacement is advanced by a smaller compressive load immediately after the impact is applied, so the stress is generated slowly and the initial maximum stress is generated. The impact absorbing performance in the initial stage is relatively low late. On the other hand, in the vehicle shock absorber having a pair of concave ribs and a pair of reinforcing cores, the compressive load increases immediately after the impact is applied, and the target stress is generated at a stage where the displacement is small, Impact absorption performance at the initial stage is improved.

  The vehicle impact absorber 1 shown in FIGS. 1 to 8 is blow-molded as shown in FIGS. That is, 18 and 18 are a pair of split molds, 19 and 19 are concave rib forming cavities, 20 is an extrusion die, and 21 is a parison. As shown in FIG. 10, after the parison 21 is disposed between the pair of split molds 18, 18, the mold is clamped and blow-molded as shown in FIG.

  As shown in FIGS. 12 and 12, the vehicle impact absorber 1 according to the present invention is obtained by embedding plate-like reinforcing cores 22 and 23 through openings 12 and 13 in concave ribs 6 and 7. is there. Since the concave ribs 6 and 7 have a cylindrical cup shape, cup-shaped reinforcing cores 24 and 25 may be embedded in the concave ribs 6 and 7 as shown in FIG.

  The vehicle impact absorber 1 shown in FIGS. 12 and 13 is blow-molded as shown in FIGS. 15 to 17, but the reinforcing core members 22 and 23 are concave rib-forming cavities of a pair of split molds 18 and 18. 19 and 19 are inserted into the concave grooves 26 and 26 and embedded in the concave ribs 6 and 7 at the time of blow molding.

  FIG. 18 thru | or FIG. 21 has shown the usage example of the shock absorber 1 for vehicles which concerns on this invention. 18 and 19 are examples in which the vehicle shock absorber 1 according to the present invention is provided in the door trim 28 of the door 27, FIG. 20 in the rear pillar 29 of the automobile, and FIG. 21 in the rear bumper 30, respectively. . In FIG. 20, A indicates the head of the passenger.

  The vehicle impact absorber according to the present invention is installed in vehicle components such as doors of automobiles, body side panels, roof panels, pillars, bumpers, and the like, and the impact absorbability of those portions can be significantly increased. It can be made and contributes greatly to improving the safety of automobiles.

It is a perspective view which fractures | ruptures and shows the impact absorber for vehicles which concerns on the 1st Embodiment of this invention. It is a top view same as the above. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. FIG. 4 is a partial perspective view corresponding to FIG. 3. It is a perspective view which fractures | ruptures and shows the shock absorber for vehicles which concerns on the 2nd Embodiment of this invention. It is a top view same as the above. It is CC sectional drawing of FIG. It is a graph which shows the displacement with respect to the compressive load of the shock absorber for vehicles which concerns on this invention. It is sectional drawing which shows the blow molding aspect of the shock absorber which concerns on 1st and 2nd embodiment. It is sectional drawing of the state clamped same as the above. It is a perspective view which shows the shock absorber for vehicles which concerns on the 3rd Embodiment of this invention. It is a one part perspective view same as the above. It is a partial sectional view showing a 4th embodiment of the present invention. It is sectional drawing which shows the blow molding aspect of the impact absorber for vehicles which concerns on the 3rd Embodiment of this invention. It is sectional drawing of the state clamped same as the above. It is sectional drawing of the state which opened the mold after blow molding same as the above. It is sectional drawing which shows the aspect which installed the shock absorber for vehicles which concerns on this invention in the door trim of a vehicle. It is sectional drawing same as the above. It is sectional drawing which shows the aspect which installed the shock absorber for vehicles which concerns on this invention in the rear pillar of a motor vehicle. It is a rear view of the rear bumper which installed the shock absorber for vehicles concerning the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle shock absorber 2 Hollow part 3 Perimeter wall surface 4 First wall 5 Second wall 6,7 Concave rib 8 Welding surface 9,10 Plate-like rib 11 Welding surface 12,13 Opening hole 14,15 Opening part 16,17 Reinforcing core material 18, 18 A pair of split molds 19, 19 Concave rib forming cavity 20 Extrusion die 21 Parison 22, 23 Plate-shaped reinforcing core material 24, 25 Cup-shaped reinforcing core material 26, 26 Concave groove 27 Door 28 Door trim 29 Car Rear Pillar 30 Rear Bumper 31 Concave A A Rider's Head

Claims (5)

A hollow vehicle shock absorber for absorbing a shock from inside or outside by being installed in a vehicle component,
The vehicle impact absorber is formed into a hollow shape by blow molding a thermoplastic, and has a first wall and a second wall facing each other at an interval,
A pair of concave ribs, each of which is formed by recessing the first wall toward the opposing second wall and recessing the second wall toward the opposing first wall and including one concave rib and the other concave rib, Multiple formed,
The first concave rib and the other concave rib have a welded surface in which the respective distal ends thereof are welded and integrated;
A vehicle impact absorber, wherein a reinforcing core member is embedded adjacent to a wall surface of a concave rib that protrudes from at least one of the first wall and the second wall to the hollow portion side.   The height (b) from the first wall of one concave rib to the welding surface is 15.0 to 35.0 mm, and the height (c) from the second wall of the other concave rib to the welding surface is 15 The shock absorber for a vehicle according to claim 1, wherein the shock absorber is formed in a range of 0.03 to 35.0 mm and a distance (a) between the first wall and the second wall is 30.0 to 70.0 mm. .   A pair of plate-like ribs each projecting the first wall and the second wall to the hollow portion side are formed so as to connect the concave ribs, and a welded portion is formed by welding and integrating the opposing end portions of the pair of plate-like ribs. The vehicle impact absorber according to claim 1, wherein a reinforcing core material is embedded in at least one of the pair of plate-like ribs.   The concave ribs formed on the first wall and the second wall are substantially cylindrical, and the first wall and the second wall have a substantially circular opening having a diameter (d) of 15.0 to 30.0 mm. 4. The vehicle impact absorber according to claim 1, wherein a reinforcing core material is embedded in the concave rib from the opening.   5. The vehicle impact absorber according to claim 1, wherein the insert member is made of a thermoplastic material that is the same material as the thermoplastic plastic constituting the vehicle impact absorber.

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