April 14, 1970. R. w. YANCEY 3,
SHOCK ABSORBER BUMPER Filed Oct. 14, 1968 //VV/V 70k @mma cg a PM, W M ring A T 7'0 ave-Ks United States Patent O 3,506,295 SHOCK ABSORBER BUMPER Raymond W. Yancey, Libertyville, IlL, assignor to MSL Industries, Inc., a corporation of Minnesota Filed Oct. 14, 1968, Ser. No. 767,304 Int. Cl.B60r 19/04;B61f 19/04 US. Cl. 29370 Claims ABSTRACT OF THE DISCLOSURE A bumper having impact absorbing characteristics, with the bumper including a sheet that is deformed to include spaced parallel ribbons having longitudinally spaced, alternating crests and troughs that are interconnected by webs having a m-ulti-planar torsional deformation. The impact absorbing sheet is preferably sandwiched between inner and outer members, with the impact absorbing sheet being connected to the inner member by means which allow the sheet to expand longitudinally during impact, and with the outer member being connected to the impact absorbing member by means that will readily shear during impact.
BACKGROUND OF THE INVENTION Bumpers which are in common use today on automotive 'vehicles are essentially decorative items, and do not satisfactorily protect the vehicle structure adjacent the bumpers. Such bumpers have little or no impact absorbing properties, so that when the bumper strikes another object, the forces are directly transmitted to the vehicle body. Furthermore, known bumpers are easily dented and are difficult and expensive to replace when necessary.
SUMMARY OF THE INVENTION The bumper of the present invention includes a novel impact absorbing member that is formed from an initial sheet having a pluarilty of transverse rows of longitudinally aligned openings that divide the sheet into a plurality of spaced parallel ribbons, with webs between the openings interconnecting the ribbons. The openings are relatively wide in comparison to the thickness of the sheet, and the ribbons of the sheet are deformed to provide alternating, longitudinally spaced crests and troughs that extend a substantial distance out of the plane of the sheet, with the webs having a multi-planar torsional deformation. When the initial sheet is deformed to provide the crests and troughs, and the twisted webs, the overall length of the sheet is significantly reduced, on the order of so that when the deformed sheet is impacted, the sheet will expand to its initial length before the sheet material itself is strained. In this manner, the sheet can absorb an impact and dissipate the energy thereof without transmitting the force of the impact to the vehicle structure.
The impact absorbing member is preferably provided in a sandwich structure between inner and outer. members, with the inner member having means accommodating elongation of the impact absorbing member, and with the outer member being connected to the impact absorbing member with means that will readily shear during impact.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top plan view of a first embodiment of the bumper;
FIG. 2 is an enlarged exploded perspective view of the bumper of FIG. 1;
FIG. 3 is an enlarged perspective view of the impact absorbing sheet material; and
FIG. 4 is a fragmentary top plan 'view of a modlfied bumper structure.
3,506,295 Patented Apr. 14, 1970 ice While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail a preferred embodiment of the invention and a modification thereof, with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to the embodiments illustrated.
Referring now to the drawings in detail, 'a first embodiment of the bumper is illustrated at 10 in FIG. 1, and includes animpact absorbing sheet 13 sandwiched between an outer member 11 and aninner member 12. Themember 13 is formed from a generally planar sheet of material having a plurality of transverse rows of elongate openings therein that separate themember 13 into a plurality of spaced,parallel ribbons 14, three such ribbons being illustrated in the embodiment of FIGS. 1-3. The webs between the open-ings connectthe ribbons :14 at spaced positions therealong, and each of theribbons 14 is deformed in accordance with the teachings in my concurrently filed application entitled Article of Manufacture and Method of Making the Same to provide alternating, longitudinally spacedcrests 15 between the webs andtroughs 16. As is explained in detail in my abovementioned application, thecrests 15 andtroughs 16 are defined by converging ribbon portions, and during the ribbon deforming step, the webs W are given a multiplanar torsional deformation so that they are generally uniformly twisted between their oppositely inclined end portions. Theapexes 17 of thecrests 15 are flattened and parallel with the plane of the initial sheet, with theapexes 18 of thetroughs 16 also being flattened and parallel with the plane of the initial sheet. As is evident from FIG. 1,crest apexes 17 are positioned in face abutting engagement with outer member 11, whiletrough apexes 18 are positioned in face abutting engagement withinner member 12.
Theimpact absorbing member 13 is secured to outer member 11 by shear bolt-type fasteners 20, which pass throughopenings 19 in the member 11, and through openings in thecrest apexes 17.Nuts 22 are threaded onfasteners 20 to positively secure themember 13 to the member 11, andfasteners 20 preferably are weakened, as by acircumferential groove 21, to provide a means allowing the fasteners to readily shear when themember 13 expands during impact.
Means 23 is provided for mounting thebumper 10 upon tubular vehicle chassis supports 24, andmounting means 23 are defined by rectangulartubular mounting brackets 25 having outwardly divergingsides 26 that terminate in mountingfeet 27. Mountingfeet 27 are positioned in face abutting engagement with the outer surface ofinner member 12, and mountingfeet 27 includeopenings 29 that are positionable in alignment withelongate slots 31 in theinner member 12.Fasteners 30impale openings 29,slots 31, and opening-s in thetrough apexes 18, with nuts 32 being threaded upon the inner ends offasteners 30 to secure thebrackets 25 and theinner member 12 to theimpact resisting member 13.Fasteners 30 are freely slidable alongslots 31, so that when themember 13 expands during impact, themembers 11 and 13 are free to move relative toinner member 12. The top and bottom ofbrackets 25 may be bent toward one another, as is shown at 33 in FIG. 2, withflush fasteners 35 extending through openings in thetrough apexes 18 and through openings in the folded over bracket portions.
A modified bumper structure is shown at 10' in FIG. 4, and the bumper 10' is similar to thebumper 10, except that a plurality of impact absorbing members 13' are r.) provided, with the apexes of the adjacent crests and troughs being secured to one another.
While both of the above-described embodiments have been illustrated in connection with an outer member or 10', the present invention contemplates that in certain instances the outer member may be eliminated to enhance the aesthetic appearance of the bumper.
What is claimed is:
1. A bumper comprising: an impact absorbing sheet having at least two vertically spaced rows of openings, a horizontally extending ribbon portion being provided on each side of the rows of openings and the openings in each row being separated by a web portion, each ribbon including alternating, longitudinally spaced crests and troughs, the crests extending outwardly from a vertical reference plane and the troughs extending inwardly from the reference plane, the transitional portion of each ribbon between the crests and troughs extending at an angle with respect to the reference plane, the crests on each ribbon being aligned with a trough on anadjacent ribbon whereby the aligned transitional portions of adjacent ribbons are disposed at angles that are inclined oppositely with respect to said reference plane, said webs each having a first end portion merging with a transitional portion of one ribbon and a second end portion merging with the aligned transitional portion of an adjacent ribbon, the intermediate portion of each web between its end portions being twisted throughout its length; and means for mounting said sheet upon a vehicle.
2. A bumper as set forth in claim 1 wherein said sheet includes three horizontally extending ribbons.
3. A bumper as set forth in claim 1 wherein a plurality of impact absorbing sheets are secured to one another, 'with the crests on each sheet being positioned in engagernent with a trough on an adjacent sheet.
4. A bumper as set forth in claim 1 wherein said mounting means is defined by an inner member secured to at least two of said troughs, and mounting brackets secured to said inner member and having means connectable with a vehicle.
5. A bumper as set forth in claim 4 wherein said inner member and brackets have cooperating means allowing said sheet to expand longitudinally upon impact.
6. A bumper as set forth in claim 5 wherein said cooperating means are defined by slots in said inner member, and fasteners passing through said slots and openings in said brackets.
7. A bumper as set forth in claim 1 including an outer member, and means securing said outer member to at least some of said crests.
8. A bumper as set forth in claim 7 wherein said securing means includes a plurality of fasteners, said fasteners being weakened so as to shear when said sheet expands upon impact.
9. A bum-per as set forth in claim 8 wherein said mounting means is defined by an inner member secured to at least two of said troughs, and mounting brackets secured to said inner member and having means connectable with a vehicle.
10. A bumper as set forth in claim 9 wherein said inner member and brackets have cooperating means allowing said sheet to expand longitudinally upon impact.
References Cited UNITED STATES PATENTS 1,957,515 5/1934 Williams 293-89 3,146,014 8/1964 Kroell 293- 3,265,163 8/1966 Gilbert .et a1. 188-1 3,412,628 11/1968 DeGain 293-1 FOREIGN PATENTS 446,174 6/ 1927 Germany.
DRAYTON E. HOFFMAN, Primary Examiner H. BELTRAN, Assistant Examiner US. Cl. X.R. 188l; 29387, 92, 98, 99