Method for forming a shock absorbing structural member
Abstract
Abstract A METHOD FOR FORMING A STRUCTURAL MEMBER WHICH IS ADAPTED TO REMAIN RIGID WHEN SUBJECTED TO FORCES BELOW A PREDETERMINED MAGNITUDE AND TO COLLAPSE AND ABSORB ENERGY WHEN FORCES IN EXCESS OF THE PREDETERMINED MAGNITUDE ARE IMPOSED ON IT. THE METHOD INCLUDES FORMING SHEET STEEL INTO AN ELONGATED TUBULAR CONFIGURATION, FORMING A SERIES OF REGULARLY SPACED CIRCUMFERENTIAL GROOVES OF REDUCED THICKNESS ALONG THE LENGTH OF THE TUBE, FORMING LONGITUDINAL SLITS OR CUT-OUTS IN THE TUBE, AND THEN OUTWARDLY EXPANDING THE TUBE AT ALTERNATE PAIRS OF GROOVES SO THAT ALTERNATE TUBE SECTIONS ARE EXPANDED TO A LARGER DIAMETER THAN INTERMEDIATE TUBE SECTIONS. ALTERNATIVELY, THE TUBE MAY BE EXPANDED AT EACH THIRD GROOVE, WITH INTERMEDIATE TUBE SECTIONS RETAINING THEIR ORIGINAL SHAPE.
Inventors
- 👤 William J De Gain
Bibliographic Details
Claims Analysis
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