| 摘要 |
PROBLEM TO BE SOLVED: To obtain high mechanical characteristics values by a method wherein a diameter or a width and a thickness of a runner is at least a length of a fiber being a reinforcing agent in a fiber reinforced resin supplied for molding, and a gate part connecting the runner with a cavity is constituted by a radius of curvature corresponding to a length larger than a specific value of times a length of a fiber required for a molded product. SOLUTION: Since a diameter of a runner 1 and a diameter of a gate 2 are made 1.25 times at least a length of a fiber being a reinforcing material in a long fiber reinforced thermoplastic resin supplied to the runner 1, shearing stress acting on twisted fibers in the melt resin can be reduced. When shearing stress acts on the fiber, a space necessary for rotation or the like of the fiber can be secured, and the fiber can be prevented from being cut. Further, since an R of 2.3 times more than 2 times a length of a fiber required in the product in a cavity is provided to the gate 2, an inflection point of the fiber is prevented from occurring, and a sudden changed part of a flow state of the resin is excluded. |
