Patent ID: 7174873

Claim:
A welding structure for a synthetic resin intake manifold, comprising: a synthetic resin passage structural member that forms at least one portion of the synthetic resin intake manifold; a synthetic resin intake manifold body to which the synthetic resin passage structural member is welded along a joining line that has a loop shape; a first joining flange provided on the synthetic resin intake manifold body along the joining line; a second joining flange provided on the synthetic resin passage structural member along the joining line; a protrusion provided on the first joining flange and protruding toward the second joining flange; a welding protrusion provided on the second joining flange, the welding protrusion protruding toward the first joining flange and being welded to the protrusion; and an inside control wall and an outside control wall which respectively protrude toward the first joining flange at an inside and an outside of the joining line, and which are respectively provided to either side of the welding protrusion, wherein the synthetic resin passage structural member is positioned and aligned with respect to the synthetic resin intake manifold body along the joining line prior to welding such that a volume of an inside burr retaining groove formed by the protrusion of the first joining flange and the inside control wall of the second joining flange and the welding protrusion of the second joining flange is set to be larger than a volume of an outside burr retaining groove formed by the protrusion of the first joining flange and the outside control wall of the second joining flange and the welding protrusion of the second joining flange, and wherein an entire surface of the protrusion facing the welding protrusion and an entire surface of the welding protrusion facing the protrusion are substantially perpendicular to a pressing direction.