| 摘要 |
736,509. Making bags. WINGFOOT CORPORATION. Aug. 6, 1952 [March 10 1952], No. 19771/52. Class 94 (2). [Also in Group VIII] In an arrangement for simultaneously edge-sealing a plurality of superposed thermosealable bag blanks, the package of bag blanks 1 comprises pairs of thermoplastic sheets separated by sheets of insulating material, e.g. paper, a piece of hardboard 4 being placed on the top and bottom of the stack and the whole being held by encircling bands 5, 6 of heat stable material such as paper. Alternatively the package may be completely covered with paper. The package is placed on the base 8 in contact with the fixed heating elements 10 and 12, and the adjustable heating element 17 is moved into position and clamped by the wing nut 16. The heaters are controlled by a thermostat 20. Specification 641,808 is referred to. |
