Elastomeric energy absorbing mechanism for vehicle bumpers
AssigneeConcept Analysis Corporation
InventorsPatrick M. Glance, Paul Glance
Life of this patent
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Abstract
An elastomeric energy absorbing bumper mounting mechanism for a vehicle comprises an energy absorbing block formed of an elastomeric material, desirably a crystalline thermoplastic polyester material, formed into an intersecting grid of elastomeric walls, with a stiffer inboard side than outboard side, thickened peripheral end walls, triangular reinforcing cells, tapered cell walls, thickened posts at the intersections of certain walls, and a portion of partial length cells. The block is heat staked to rigid end plates at each end to form energy absorbing units, and the end plates are bolted to a bumper beam and vehicle rail plates. Two energy absorbing units support the bumper beam and are easily replaceable and adaptable to other vehicles.
Claims33
An improved elastomeric energy absorber unit for a vehicle system, wherein the elastomeric energy absorber unit is mounted between a bumper beam and a fixed position vehicle rail so as to permit resilient, energy absorbing deflection of the bumper beam with respect to the vehicle rail within predetermined force and deflection limits designed to minimize damage to the vehicle, the elastomeric energy absorber unit comprising a resiliently collapsible energy absorbing block formed of an elastomeric material, the block having an egg crate configuration comprising a plurality of substantially parallel elongated tubular channels extending axially between front and rear ends of the block, with elastomeric walls separating adjacent channels, each channel and the walls forming the periphery thereof being a cell, the block being offset from the center of the vehicle and having an inboard side designed to face inwardly toward the center of the vehicle and an outboard side designed to face outwardly toward the side of the vehicle, the inboard and outboard sides of the block each including means for resisting axial collapse thereof, the inboard means providing greater resistance to axial collapse than the outboard means, such that the inboard side of the block is more resistant to axial collapse than the outboard side of the block, the block resisting inward bending moments and urging the block to collapse axially in a front to rear direction in response to an impact load at the center of the bumper team.
An improved elastomeric energy absorber unit for a vehicle system, wherein the elastomeric energy absorber unit is mounted between a bumper beam and a fixed position vehicle rail so as to permit resilient, energy absorbing deflection of the bumper beam with respect to the vehicle rail within predetermined force and deflection limits designed to minimize damage to the vehicle, the elastomeric energy absorber unit comprising a resiliently collapsible energy absorbing block formed of an elastomeric material, the block having an egg crate configuration comprising a plurality of substantially parallel elongated tubular channels extending axially between front and rear ends of the block, with elastomeric walls separating adjacent channels, each channel and the walls forming the periphery thereof being a cell, the end of at least one of the walls at at least one end of the block being thicker than the portion of the wall adjacent the end, the thicker end providing a wider and more stable base for receipt of an impact force against the end of the block the unit including rigid end plates mounted on the ends of the block, the block having thermoplastic heat stake tabs extending outwardly from at least the thickened portions of the ends of the block and fitting through mating openings in the rigid end plates, portions of the tabs extending through the end plates being melted to form enlarged rivet type heads that lock the end plates on the ends of the block, the thickened portions providing a sturdy base for the tabs and a widened bearing surface for the end plates.
An elastomeric bumper mounting mechanism for a vehicle bumper system wherein a transverse bumper beam is mounted on spaced vehicle frame rails, the elastomeric mounting mechanism being mounted between the bumper beam and the rails so as to permit resilient, energy absorbing deflection of the bumper system with respect to the vehicle rails within predetermined force and deflection limits designed to minimize damage to the vehicle, the elastomeric mounting mechanism comprising an energy absorber unit for each vehicle rail, each energy absorber unit comprising:
- a resiliently collapsible energy absorbing block formed of a moldable elastomeric material, the block having an egg crate configuration comprising a plurality of substantially parallel elongated tubular channels extending between front and rear ends of the block, with elastomeric walls separating adjacent channels, each channel and the walls forming the periphery thereof being a cell, certain portions of the walls of each block at the ends thereof extending beyond the end of the block and forming heat stake tabs on the blocks;
- substantially rigid end plates mounted on the front and rear ends of the block, the end plates having openings therein through which the heat stake tabs fit, outer ends of the tabs being melted to form enlarged heads on the tabs that lock the plates on the ends of the block, the plates abutting the ends of the block and serving to distribute end to end compression forces exerted on the block over the cells of the block and urging uniform compression deflection of the block in response to such forces and urging return to original shape after each impact;
- and
- fastening means for attaching one end plate of the block to the bumper beam and the other end plate to the vehicle rail, whereby the bumper is suspended from the vehicle rail by the elastomeric energy absorbing unit.
An energy absorbing bumper mounting mechanism for a bumper system wherein a bumper beam is mounted on spaced vehicle rails, the mounting mechanism including an energy absorbing unit mounted on each vehicle rail and suspending the bumper beam from the energy absorbing units, each energy absorbing unit comprising a resiliently collapsible block formed from an elastomeric material, the block having an egg crate configuration with elongated substantially parallel channels being longitudinally oriented between front and rear ends of the block, the ends of the block having heat stake tabs extending outwardly therefrom, the heat stake tabs on the rear end of the block extending through mating openings in a substantially rigid rear end plate and being enlarged on the side opposite the block to lock the block on the end plate, the rear end plate being releasably fastened to the vehicle rail, the tabs on the front of the block extending through mating openings in a substantially vertical mounting surface for the bumper beam and being enlarged on the side opposite the block to lock the block on the vertical surface, the bumper beam being thus suspended from the vehicle rails by the blocks, without vertical supporting engagement between a horizontal side of the bumper beam and a horizontal side of the block, thereby avoiding interference between the bumper and the block as the bumper beam moves back and the block collapses under impact on the bumper beam.
An energy absorbing mounting mechanism for a bumper system wherein a bumper beam is mounted on spaced vehicle rails, the mounting mechanism including an energy absorbing unit mounted on each vehicle rail and suspending the bumper beam from the energy absorbing unit, each energy absorbing unit comprising a resiliently collapsible block formed from a resilient material and a pair of substantially rigid end plates mounted respectively on front and rear ends of the block, one end plate being bolted to the bumper beam and the other end plate being bolted to an outer end of the vehicle rail, such that energy absorbing units can be bolted and unbolted from the vehicle rails and the bumper beam for easy installation and replacement, the end plates also serving to distribute impact forces evenly over the ends of the blocks and assisting in guiding the blocks to collapse smoothly on impact, the block being formed of an elastomeric material having an egg crate configuration wherein a plurality of substantially parallel elongated tubular channels extend axially between front and rear ends of the block, with elastomeric walls separating adjacent channels, the end plates being mounted on the egg crate blocks by means of integrally formed tabs that extend from the ends of the elastomeric walls and fit through mating openings in the end plates, outer ends of the tabs being enlarged to a size greater than the openings so as to lock the plates on the blocks.
An improved elastomeric energy absorber unit for a vehicle system, wherein the elastomeric energy absorber unit is mounted between a bumper beam and a fixed position vehicle rail so as to permit resilient, energy absorbing deflection of the bumper beam with respect to the vehicle rail within predetermined force and deflection limits designed to minimize damage to the vehicle, the elastomeric energy absorber unit comprising a resiliently collapsible energy absorbing block formed of an elastomeric material, the block having an egg crate configuration comprising a plurality of substantially parallel elongated tubular channels extending axially between front and rear ends of the block, with elastomeric walls separating adjacent channels, each channel and the walls forming the periphery thereof being a cell, the block including at least one modified peripheral cell wherein an outer side of the cell is tapered inwardly along its length as it extends from the rear end to the front end of the cell, giving the channel a triangular configuration, the tapered cell serving to enhance the stability of the block and to urge the block to collapse or deflect linearly in an end-to-end direction when the bumper is subjected to an impact.
Dependencies are inferred from the claim text.