| 摘要 |
<p>1,253,437. Separable fastener. AMERICAN VELCRO Inc. 11 Aug., 1969 [12 Aug., 1968], No. 40081/69. Heading E2S. A hook member for a separable fastener of the type in which two complementary surfaces have hook and loop engaging elements, is made from non-woven material. The material consist of either a bilaminate or uniaxial or biaxial material e.g. polyethylene terephthalate. The material is characterised in that it shrinks when treated in some way e.g. by heat. If the surface only is treated the material distorts. Triangular cuts 16 (or rectangular), are stamped in the sheet 11. These are bent out of the plane of the sheet, as at 22A, subsequent heat treatment forms them into hooks 12. The hooks are formed in rows with adjacent rows of hooks pointed towards each other. The hooks are aligned parallel to an axis of assymetry 20. A backing sheet 13 may be applied by adhesive 14 to the hook sheet 11. The hooks are made by first stamping the triangular cuts in the sheet as at 22 in Fig. 5. The triangular members are forced out of the plane of the sheet by spiked wheel 23. A heating mask sheet 25 passes over the hook strip so that only the hooks are exposed to subsequent heat treatment. The hooks are heated by an infra red lamp 31 and shutter system 37, 39 which forms two heat beams 34 and 35. These beams are scanned over the hooks from the tips to the roots. The wheel 23 advances the strip intermittently and pairs of rows of hooks are heat treated together.</p> |
