摘要 |
<p>A vehicle seat belt retractor has a spool fitted around the shaft of the reel, the spool having a slot formed at a radial step through which the belt extends from a securement to the shaft. The outer surface of the spool otherwise comprises two or three part circular cylindrical portions which smoothly merge. The step approximates to the thickness of the belt so a smooth spiral configuration is obtained for the coiled belt but only cylindrical surfaces, and not a spiral surface, have to be produced, with manufacturing advantages. The spool can be of a size to accommodate any doubled portion of the belt required to form a securement loop. The spool increases the effective diameter of the reel and so reduces spring tension on the belt in use.</p> |