| 摘要 |
1,146,959. Seaming non-metallic sheet material. ANDERSON BROS. MFG CO. 21 Nov., 1967 [27 Feb., 1967], No. 52969/67. Heading B5K. [Also in Divisions B6 and B8] In apparatus for wrapping articles in heatsealable sheet material (see Division B8) the sheet material, after wrapping round the article, is brought together in overlapping relationship and clamped between a pair of co-operating jaws, each of which travels in an independent endless path, and, whilst so clamped is sealed and severed by electrical impulse heated means incorporated in one of the jaws. The upper jaw includes a central member 101 in the form of a relatively thick bar and forward and rear clamping jaws 102 and 103 movable relatively to the central member for a limited distance. A sealing jaw face having a strip 118 of dielectric material and preferably covered with a flexible layer of P.T.F.E. impregnated glass fibre is attached to member 101 and a heat sealing and cutting element 124, adapted to be impulse heated, is mounted to overlie the sealing face. The lower jaw includes front and rear clamping members 143, 144 interconnected by a cross-piece 146 to form a U- shaped member and an intermediate sealing jaw member 145 supported for relative movement therein. The member 145 includes a dielectric strip 147 of resilient heat-resistant material and may also be covered with a flexible cover of P.T.F.E. impregnated glass fibre. The jaws are mounted on independent endless chains driven in synchronism so that the jaws come into co-operative engagement along a common horizontal run so as to grip the heat sealable material therebetween and whilst moving with the gripped material to seal and sever the material. The relative gripping and sealing movements of the jaws are effected by cam surfaces and the sealing and cutting element is connected to an electric impulse source by sliding brushes operating on conductive shoes. More than one pair of co-operating jaws may be attached to the endless chains. |
