FIELD: technological processes.
SUBSTANCE: device (10) for injection moulding of an opening device (3) on a multi-layer sheet packing material (2), where there is a hole (9), having an axis (B) and created through the first layer (4) and sealed with a coating section (11) of the second layer (5, 6). The device comprises a shaping cavity (31), where the coating section (11) is arranged coaxially, and comprises the first chamber (32) of plate shape, made as capable of filling with molten plastic at the first side (11a) of the coating section (11), and the second tubular chamber (33), protruding along the axis (B) from the first chamber (32) and made as capable of filling with molten plastic. The latter arrives from the first chamber (32) via a circular peripheral section of the coating section (11) to produce on the second side (11b) of the coating section (11) a spout (13) of the opening device (3). The device also comprises a circular rib (41), creating a passage (42) of the small cross section, which connects the first and second chambers (32, 33) and forming, when filled with plastic, a circular connecting section (19) of a ruptured membrane between the spout (13) and plastic, covering the coating section (11). The rib (412) is limited on the side of the first chamber with a circular surface (43), parallel to the axis (B), and forms a sharp edge (46), on which the coating section (11) stretches under pressure of the molten plastic.
EFFECT: exclusion of a rupture on the side of the spout and introduction of a part of a material laminated hole into plastic material forming a tear-off membrane.
14 cl, 7 dwg
