INTAKE-AIR DEVICE IN ENGINE

PURPOSE:To enable a mixture to be uniformly distributed, in an intake-air manifold having branch passages for distributing the mixture to engine cylinders, by providing, upstream of the branch points of the branch passages, guide members for changing the direction of the wall surface flow of fuel in accordance with the temperature of intake-air. CONSTITUTION:A substantially elliptical-shape intake port 2 which is communicated at the center thereof with a carburettor and at the right and left thereof with a main passage 4, is opened to a tournament type intake manifold 1 for a four-cylinder engine. Further, branch passages 5, 6 and 7, 8 are connected to the right and left ends of the main passage 4, respectively, each passage being bent in one direction. In such a manifold 1, guide members 18, 19 are disposed in the vicinity of and upstream of the branch points 15, 16 of the branch passages 5 through 8, the guide members being directed toward the branch points 15, 16 from the inner wall 17 in the curved part of the main passage 4. These guide members 18, 19 are formed of a plate-like member such as, for example, a bimetal which increases its curvature as the temperature of intake-air rises.