| 摘要 |
1,067,171. Boots &c. BRITISH UNITED SHOE MACHINERY CO Ltd. Nov. 8, 1963 [Nov. 18, 1962; Oct. 23, 1963], Nos. 35575/62 and 41918/63. Heading A3B. The components of an upper i.e. outer material 16, stiffeners 13, 18, 19 and lining 20 are bonded together under pressure using an adhesive which is activated by a high frequency electric field. In a first embodiment Fig. 1 the components are assembled on a lower platen 10 using spring loaded pins 13 to position the components and the adhesive is activated by a high frequency electric field. The platens 10, 11 constitute the H.F. electrodes. In a second embodiment (Fig. 5 not shown) the components are assembled on a jig (not shown) similar to the lower platen 10 and are temporarily secured together by spots of pressure sensitive adhesive or by spot welding. The adhesive is activated by micro-wave heating using electro-magnetic oscillations having a frequency of 3,000 to 30,000 m.c.p.s. which are fed along a waveguide (21) into a rectangular metal box (22), so proportioned that a standing wave is produced within it, along its length. The components pass through the box on an endless band of glass fibre fabric impregnated with polytetrafluorethylene, the longitudinal axis of the band being at an angle of 30 degrees to 45 degrees to the axis of the box. The components are pressed together by rollers (26). Suitable adhesives are adhesives having a high dielectric loss such as plasticized polyvinyl acetate, acrylic esters, polyurethanes, polyvinylidene chloride or polychloroprene. Surface decoration such as stitch-marking, design embossing or perforating of the layer of outer material may be effected during the bonding. |
