Patent ID: 8127539

Claim:
An exhaust manifold comprising: a plurality of branch pipes that are connected with a head flange; an adapter member; and a collecting part that is connected with exhaust-gas downstream side end portions of the branch pipes through the adapter member, wherein the adapter member has a ring portion and a reinforcement portion that is formed like a pillar with the ring portion as one unit, the pillar being formed along from an exhaust-gas upstream side end surface of the ring portion to an exhaust-gas downstream side end surface of the ring portion and toward a center of the ring portion from the ring portion, wherein the exhaust-gas downstream side end portions of the branch pipes are inserted into insertion holes formed between the ring portion and the reinforcement portion of the adapter member so that exhaust-gas downstream side end surfaces of the branch pipes are located on the same plane as the exhaust-gas downstream side end surface of the adapter member; and wherein the adapter member and the exhaust-gas downstream side end portions of the branch pipes are fixed with each other by a circular weld line formed along outer circumferences of the exhaust-gas downstream side end portions of the branch pipes at the exhaust-gas downstream side end surface of the adapter member and a weld line formed along adjacent side wall portions of the branch pipes.