91 Chrysler Le Baron Rear Bumper
91 Chrysler Le Baron Rear Bumper
(OP)
Question is, are the two bumper springs meant to absorb 100 percent of the horizontal force of a rear end collision at any point up to their failure at full compression? To put in a numerical perspective, if the impact loading is 2000 pounds, and say the capacity of the two springs is 3000 pounds asorbed at 100% compression, will the occupants feel any force? If not, why not? If so, why so?
Mike McCann
MMC Engineering





RE: 91 Chrysler Le Baron Rear Bumper
The usage of the term "absorb" is misleading, I think. "Absorb" implies that the springs magically suck up the energies, but, the springs compress, and then they want to uncompress. Not that much winds up as heat.
TTFN
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RE: 91 Chrysler Le Baron Rear Bumper
RE: 91 Chrysler Le Baron Rear Bumper
Do you have any study/test references with any energy dissipation curves with respect to the time of the impact for these or similar bumper springs - really a damper? Anything relating to accelerations seen with respect to the percentage of the permanent compression of the spring?
As I understand it, the "springs" as I referred to them, permanently compress on impact to a length that depends on the force seen in the impact, having to be replaced after each rear end collision. So these are really energy absorbing mechanisms, returning no energy back to the overall system.
Mike McCann
MMC Engineering
RE: 91 Chrysler Le Baron Rear Bumper
- Steve
RE: 91 Chrysler Le Baron Rear Bumper
I'd be slightly surprised if there were no published papers on this, albeit not your model in particular. Oh, and glass fibre tubes were in vogue for a while.
Cheers
Greg Locock
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RE: 91 Chrysler Le Baron Rear Bumper