Collecting part structure of exhaust manifold

Abstract

A collecting part structure of an exhaust manifold, in which connecting portions of branch pipes 2 to 5 to a head flange 1 are arranged on a straight line, has a reinforcement member that includes two flat plates 10 and 11 to collect and fix downstream side portions f the branch pipes 2 to 5. The flat plates have the same length as an inner diameter of a collecting part 6, and are formed at central positions thereof with slits S 1 and S 2 facing each other to be joined with each other like a cross shape. The flat plate 11 with the slit S 2 at an exhaust-gas upstream side, of the two flat plates 10 and 11, is arranged on a line A 2 parallel to a line on which the connecting portions of the branch pipes 2 to 5 to the head flange 1 are arranged.

1 . A collecting part structure of an exhaust manifold including four branch pipes in which exhaust-gas upstream side end portions thereof are connected with a head flange on a straight line, exhaust-gas downstream side end portions thereof being formed to have a cross section of a quadrant circle; a collecting part that collects and contains the exhaust-gas downstream side end portions of the branch pipes to form a circular cross section; and a reinforcement member that is disposed among the exhaust-gas downstream side end portions of the branch pipes to fix the exhaust-gas downstream side end portions to the collecting part, the reinforcement member having two flat plates with the same length as an inner diameter of the collecting part, the flat plates being provided at central positions with slits facing to each other to be joined like a cross shape, the collecting part structure characterized in that
 one flat plate, of the flat plates, that is formed with a slit at an exhaust-gas upstream side thereof is arranged parallel with the straight line on which connecting portions of the exhaust-gas upstream side end portions to the head flange.