| 摘要 |
PURPOSE:To prevent the generation of hesitation marks on the surface of skin resin by a method wherein the finishing position of skin resin injection is detected and the driving servomotor of a core resin injection screw is controlled so as to start the injection of core resin in synchronized with the finishing of the skin resin injection. CONSTITUTION:The movement of a skin resin injection screw 2 is controlled through pulse control so as to stop at a given position at all times in order to keep the amount of skin resin J1 in constant. Simultaneously with the stopping of the skin resin injection screw 2 at a prescribed stopping position, a core resin injection screw 3 is started by the count of a pulse number. A driving cylinder 30 for an inner tube is advanced to close the injection port of an outer tubular body 25 and, simultaneously, a driving cylinder 31 for needle is retreated to open the injection port of the driving cylinder 30 for the inner tube whereby a resin injection device B is switched from the injection of the skin resin J1 into the injection of core resin J2. By the switching, the core resin J2 is loaded into the skin resin J1 instantaneously and expanding bonding is effected without generating any hesitation work. |
