Kneading method for fiber-reinforced thermoplastic resin, plasticizing device, and extruding machine

A fiber-reinforced thermoplastic resin plasticizing apparatus comprising:

• a cylinder;
• a screw rotatable in the cylinder;
• and
• a reinforcing fiber supply device including a plurality of fiber reinforcing rolls,
• wherein a thermoplastic resin is supplied to the cylinder and melted while reinforcing fibers are supplied, and the thermoplastic resin and reinforcing fibers are kneaded to obtain a fiber-reinforced thermoplastic resin,
• wherein the cylinder comprises reinforcing fiber inlets at a plurality of locations in the cylinder,
• wherein the reinforcing fiber supply device is configured to input the reinforcing fibers into the reinforcing fiber inlets respectively from the plurality of fiber reinforcing rolls to the plurality of locations at a same time,
• wherein a clearance between a bore of the cylinder and a flight of the screw becomes larger on a downstream side than on an upstream side from a predetermined location among the plurality of locations of the reinforcing fiber inlets;
• wherein the bore of the cylinder has a shape in which:
• at a first position that is downstream of a thermoplastic resin supply and upstream of at least one of the reinforcing fiber inlets, barrel chips are formed at two locations;
• and
• from a second position that is downstream and immediately adjacent to the first position to a third position that is downstream of the at least one of reinforcing fiber inlets, at least one of the barrel chips is cut, the second position being upstream of the at least one of the reinforcing fiber inlets;
• wherein the bore from the second position to the third position has a larger cross-sectional area than the bore at the first position.