Abstract: An apparatus is provided for molding an article of footwear having an outer sole, a lateral sole and an inner sole, the outer and lateral soles being of an elastomer, and the inner sole being of a thermoplastic or a mixture of isocyanate and a polyol reacting into polyurethane. The outer sole and the inner sole are each injection molded from an elastomer and bonded at their common contact zone by full vulcanization. The outer sole and the lateral sole may each be of different elastomers. The outer sole and the inner sole are bonded together in the area of their contact zone via chemical bonds between the isocyanate and reactive end-groups of substances added to the elastomer.

Abstract: Disclosed is a hydraulically controlled extruder injection molding unit which includes a measured value pick-up for the position of the piston rod of the working cylinder and/or of the injection piston. A pressure control valve which can be switched on is provided in the line leading to the surge chamber of the working cylinder for the piston. A proportionally controlled pressure valve is provided in the line to the other surge chamber, the value being controlled as a function of dropping control values when switching from subsequent pressure to dynamic pressure until the measured value pick-up emits an output signal. The then existing instantaneous value of the dynamic pressure is then added to the preselected dynamic pressure. Consequently, the dynamic pressure phase takes place under a corrected dynamic pressure.

Abstract: An injection mold device for forming an article such as footwear from a plastic material includes a two-part male die such as a boot last, a fabric liner covering the male die, and a split female die surrounding the male die in spaced relation and forming together therewith a mold cavity. Beyond the upper end of the cavity, liner retaining pins on the male die extend outwardly of the peripheral wall thereof for retaining the liner in place during the injection molding operation. One of the pins is mounted for retracting axial movement for disengaging the tip thereof from the liner, and such pin bears against a sloping bearing surface of a first removable male die part which facilitates such retracting movement upon a relative shifting of the parts. The other pins are rigidly mounted in the male die part and project into recesses of the female die having undercuts and grooves extending between the recesses and the mold cavity.