To solve an uneven thickness problem by controlling the bending of a nipple tip part independent of the flow velocity and flow rate of a coating resin.
The cross head has a nipple 5 having a tip part 17 which is set in a die 3, expanded/contracted from a taper surface, and formed cylindrically, a core wire passage 13 in which the core wire 11 passes through the central part of the nipple 5, and a coating resin passage 19 which is formed by the outside die 3 and the inside nipple 5 and in which the coating resin coating the core wire 11 from the core wire passage 13 flows. The coating resin passage 19 is formed from a horizontal passage part 21a having an annular cross section surrounding the periphery of the tip part 17 and taper passage parts 21b, 21c and 21d which are connected to the passage part 21a and in which a resin inflow angle θ is expanded stepwise, and the angle θ of the taper passage part 21b to the passage part 21a is set to be 10-25°. The length of the nipple 5 tip part 17 is made 2-4 mm to be equal to that of the passage part 21a.
Iwa Saki Kokuni
Kawamata Sumio
Shunichi Takahashi
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