Energy absorber with crush boxes and back straps

An energy-absorbing apparatus for a vehicle, comprising:

• a reinforcement beam for a vehicle;
• an energy absorber abutting a front of the beam and including at least one hollow crush box configured to absorb energy upon impact in a fore-aft direction;
• the crush boxes each including top and bottom horizontal side walls and opposing vertical side walls and including an end wall connecting outer edges of the horizontal and vertical side walls to define a rearwardly-open cavity;
• a second wall-stabilizing component defining at least one back strap extending across a rear of the rearwardly-open cavity of one of the hollow crush boxes, the energy absorber including fasteners that extend through the component and into the beam to anchor rear edges of the top and bottom horizontal side walls together to prevent unacceptable separation of the rear edges of the top and bottom horizontal side walls during an impact in the fore-aft direction against the energy absorber.

A method of constructing an energy-absorbing article for a vehicle, comprising steps of:

• forming an energy absorber to include a base flange that, when in a car-mounted position, defines an abutment surface extending in a longitudinal direction and in a vertical direction and that is adapted to engage a face surface of a bumper beam, the energy absorber including a hollow crush box extending from the base flange in a fore-aft direction and that is configured to absorb energy upon impact in the fore-aft direction;
• the crush box including top and bottom horizontal side walls and opposing vertical side walls and including an end wall connecting outer edges of the horizontal and vertical side walls to define a rearwardly-open cavity;
• forming at least one back strap;
• and
• attaching the at least one back strap across a rear of the rearwardly-open cavity of the hollow crush box to anchor rear edges of the top and bottom horizontal side walls together near the base flange at a location spaced inward of the vertical side walls to prevent unacceptable separation of the rear edges of the top and bottom horizontal side walls upon an impact in a fore-aft direction against the energy absorber.