Method of manufacturing pipe with branch

Abstract

The present invention includes injecting a molten resin into a main cavity, which has on its one end a pressure port provided with a floating core and on its other end a first outlet, and a branch cavity, which communicates with the main cavity and has on its end a second outlet allowed to open and close, injecting a pressurized fluid through the pressure port after the injection of the molten resin, and moving the floating core to the first outlet side, and, at the same time, extruding the molten resin from the first outlet to form a main pipe hollow, and opening the second outlet after the main pipe hollow reaches a portion at which the branch cavity communicates with the main cavity, and extruding the molten resin by the pressurized fluid from the second outlet to form the branch pipe hollow.

Dependencies are inferred from the claim text.