Patent FR-2782067-A1 (FR)
Title: Closure for bottle with drinking straw to contain carbonated beverages has molded neck and coaxial tube forming immovable apron with cap to twist off at break line
Inventor: NATAF PAUL
IPC: B29C45/26
Filed: 1998-08-04
Abstract: To produce the closure for a bottle holding carbonated liquids and with a drinking straw, a steel injection mold is used to mold a plastics cylinder tube with a projecting tube section (15) at its upper end.  A second and coaxial projecting tube section (16) is locked to the outer tube (15) by a vertical membrane (M) in the vertical and hollow space of the bottle neck (15) between it and the inner extension (16a) of the second tube, but independent of its wall. After closure by the die action on the base, the material is blown into the mold. The second projecting tube (16) has a horizontal and circular projection as a thin blade (L) which can be raised at its outer periphery by the pressure of a carbonated liquid, such as a beverage. The membrane (M) is inserted into the bottle neck (15) at the inner tube (16) as far as the inner neck (15) limit for the lower inner tube projection (16a). The two-part mold has a hollow trench at the upper male section across its butting face, recessed in a circular honeycomb with notches. The facing female mold section forms the injection ring cavity for the bottle neck (15) and its flats (18'). The second mold section has three vertical blower passages, where two open over the neck (15) opening and preferably flanking the membrane (M), and the third opens over the hollow tube closed at the top to butt against the lower surface of the second mold section flanking the third passage. The trench at the male section has a center passage across it, in a longitudinal and cylindrical shape, which itself contains a coaxial hollow steel tube, preferably closed at the top to form an inner cooling channel. The hollow channel has two diametrically opposed openings as a direct link with the trench openings, shaped by two rows of vertical and parallel pins in the shape of the figure 1, for the injection of the membrane (M). A thin and circular opening matches a horizontal and semi-circular opening, hollowed at each of the butting surfaces of the shells, with a direct link between them for the injection of the circular blade (L). The female mold section also has the hollow zone for the injection molding of the coaxial inner tube (16) and also the passage which ends at the inner limit of the membrane (M) at the male mold section. An Independent claim is included for a monobloc closure with an apron which clings tightly round the bottle neck (15) to lie on the flat (18') as a limit, with a lock (1') at the flat (18'). It is extended (2) to give a partial non-sealing cover round the neck (15) with a shoulder (2') and a support (17') for the blade (L) in an immovable assembly. It is extended by a removable cap (3), with a weakened and thinner break point (19). The cap covers (4) the opening of the projecting tube (16). The cap (3) can be held to the immovable section by a thin and flexible bond, formed by extrusion molding. The cap (3) has two opposing projections, as a grip to twist off the cap. The projecting grips can be of metal or plastics, formed during molding, to twist off the cap and separate it from the immovable section along the line of least resistance. The break line can be a continuous ring of thinner material, or intermittent thin zones forming a weaker line in the material.