| 摘要 |
<p>A portable back rest, composed of one planar sheet of material adapted particularly, but not exclusively, for use on stadium, or the like, bleacher or plank seats which are not provided with backs. The back rest is of unitary one piece construction and comprises a sheet of material in generally planar configuration which may be stamped or molded into the proper flat configuration for ease of transport and storage. The material from which the back rest is stamped or molded, is flexible so that it may be flexed from its flat transport and storage condition to its operative condition for combination with a bleacher seat. The one piece planar sheet of material from which the back rest is made, has an inherent "memory," or self adjusting characteristic, which urges it at all times to assume its flat transport and storage condition. The back rest is provided with means integral therewith for releasably clamping or locking the back rest in operative position on a bleacher seat. The "memory" or self adjusting characteristic of the sheet from which the back rest is made serves a dual function, it permits bending the back rest for combination with the bleacher seat, and because of this "memory," the releasable clamping or locking means are urged into back rest supporting and maintaining position on the bleacher seat, and this inherent "memory" also functions to automatically return the back rest to its flat transport and storage condition when the clamping or locking means is released from the bleacher seat.</p> |
