Low inertia energy absorption unit

摘要

849,650. Unwinding; straightening. VAN ZELM ASSOCIATES Inc., and ZELM, VAN W. D. Jan. 5, 1959 [May 26, 1958], No. 393/59. Class 83 (4). [Also in Group XXXIV] An energy-absorbing device comprises an elongated metal strip formed into a coil, means for unwinding the coil from inside thereof and means for absorbing the kinetic energy of the moving strip after it has been withdrawn from the coil. In the embodiment illustrated, a stationary coil container 8, mounted on the ground adjacent an aircraft runway 3, is arranged to house several hundred feet of metal strip 7. The coil of metal strip 7 may be unwound from its centre and passed over guide rollers 11, guide-wheel 12 and guide roller 16 to pass into a metal bender 9 which consists of a fixed member 20 having a plurality of rollers 21 rotatably mounted along one edge and a movable frame 22 pivoted at 23 at one end which also has a set of rotatably mounted rollers 24 along one edge thereof, staggered in relationship to the rollers of the first member so that as the strip 7 passes from the container 8 and through the two sets of rollers 21, and 24, each increment of strip 7 will be progressively and successively deformed beyond its yield-point. The metal strip 7 as it emerges from the bender 9 passes between another set of guide-rollers 25 in contact with the edges of the strip and finally between a pair of guide rollers 26 contacting the face of the. strip which allow for kinetic energy load, which may be an aircraft secured to the cable 4, to be absorbed from any direction over more than 180 degrees in front of rollers 26. A modified form of bender is disclosed in the Specification which functions essentially as that described above but has the additional feature that, after threading the strip through the metal bender 9 and adjusting the pre-loading of the strip, the load may be subsequently varied at will or in response to rate of movement or length of feed of the strip. Depending upon the load to be absorbed, absorption of energy can be adjusted automatically relative to the speed. Specification 840,540 is referred to.