Process and extrusion blow molding machine for the production of flat bottles

摘要

PCT No. PCT/DE87/00033 Sec. 371 Date Nov. 30, 1987 Sec. 102(e) Date Nov. 30, 1987 PCT Filed Jan. 30, 1987 PCT Pub. No. WO87/04661 PCT Pub. Date Aug. 13, 1987.A method of making flat bottles with flat or concave bottom by free extrusion of a plastic tube includes blowing of an intermediate form with circular cross section and shaping the latter essentially mechanically to the flat bottle at simultaneous final blowing for achieving clean radii. It is essential that the intermediate form is blown at a length corresponding to about the height of the flat bottle, with a circumference in the body area of -1 to about -10%, however, in the bottom near area of the side walls from 0 to about +15%, with regard to the corresponding circumference of the flat bottle. The radius of curvature at the junction from the body wall to the bottom should correspond to about the radius of curvature at the junction from the body wall of the broad side of the flat bottle to its bottom. The bottom part corresponding to the pinched end of the tube is pinched off during shaping.