| 摘要 |
<p>1,223,879. Wrapping-machines. MIRA-PAK Inc. 15 July, 1968 [19 Dec., 1967], No. 33551/68. Heading B8C. A method of forming packages wherein a continuous web 10 of packaging material passes through a fixed former 12 where a sealing member 13 seals the opposite edges of the web to form a tube 14, and individual packages are formed from the tube by spaced transverse seals made by a pair of sealing jaws 15a, 15b, is characterized in that the former 12, and a mandrel 20 disposed in the tube 14, are moved relatively to one another to cause, in a continuous operation, the mandrel 20 to engage the first formed transverse seal 32 to draw a length of tube through the former and shape the end of the tube with a uniplanar bottom so that the subsequently formed package can stand on the flat base. The mandrel 20 has a cross-sectional shape dependent upon the desired configuration of the finished package. As shown, after a filled package A has been severed by a knife 16a and slot 16b in the sealing jaws 15a, 15b. The mandrel 20 is lowered to pull down a further package length B and flatten its base the latter being consolidated as a pivotally mounted platten 40 is raised to co-operate with the lower end of the mandrel 20. Adhesive may be applied to the seal 32 and the platten 40 may be heated. The product is introduced into the part B of the tube through the hollow mandrel 20 which is moved upwardly above the sealing jaws 15a, 15b which are subsequently then moved inwardly to form a transverse seal at the top of package B and at the bottom of the next package C. The platten 40 is then lowered and the cutters 16a, 16b are operated to sever the package B whereupon the jaws 15a, 15b are separated and the cycle is repeated. A gussetted type package may be formed by gusset bars (33), Fig. 1A, not shown, and means such as rollers, not shown, may be applied to the outer face of the tube 14 to crease the material more precisely. The position of the longitudinal seal in the tube 14 may be changed by changing the relative circumferential orientation of the former and the sealing jaws 15a, 15b.</p> |
