| 摘要 |
<p>Filters are folded from a continuous band, into a zigzag; but in an innovative step, a laser beam (13,14) perforates the embossed filter material (15) before its arrival at a delivery station (17,18) to be folded. The perforations define a form other than rectangular. Folded, the element (29) is conveyed by rotating spindles (19,20) to enter a comb-like transporter (21,22). The laser is deflected (15,16) to perforate the material. Alternatively the deflection, (15,16) or laser unit, runs on a traverse (37), over the material. In a later step, the material is sepd. into individual elements, and the shapes defined by the perforations are removed, to make the novel three dimensional shaper filter elements.</p> |
