Patent ID: 8430073

Claim:
An intake manifold, for a multiple-cylinder internal combustion engine, having a collective part defining an intake gas distribution chamber having an intake gas inlet, and a branch intake part having a plurality of branch intake passages respectively for carrying an intake gas to combustion chambers of the engine, the engine having cylinders arranged in a cylinder arranging direction; wherein the collective part is built by joining together first and second sections respectively defining first and second spaces forming the intake gas distribution chamber, at least the first section is integrally provided with a corner part, the second section is provided with a guide wall extending in the first and the second spaces and covering the inside surface of the corner part, the guide wall has a guide surface for guiding the intake gas more smoothly than the inside surface of the corner part, the guide wall opposing the intake gas inlet through the intake gas distribution chamber, wherein the intake gas distribution chamber is defined between the intake gas inlet and the guide wall such that the intake gas flowing along the cylinder arranging direction from the intake gas inlet through the intake gas distribution chamber impinges on the guide surface to be directed to the branch intake part, and wherein the guide wall and the corner part define therebetween a back space communicating with the intake gas distribution chamber by a gap defined between a free end of the guide wall and an inner surface of a wall of the first section.