Patent ID: 6725822
Filing Date: 2004-04-27
Classification: F02B,F02M,Y02T

Abstract:
An intake system for a multi-cylinder engine, in which an intake air inlet is provided in an intake air-dispensing box to lead to an intake passage in a throttle body; the inside of said intake air-dispensing box is divided by a partition wall into first and second dispensing chambers communicating with said intake air inlet, respectively; first and second intake branch pipes opening into said first and second dispensing chambers respectively and leading to intake ports in first and second banks of the engine respectively are connected to said intake air-dispensing box; and an on-off valve capable of permitting said first and second dispensing chambers to be put into and out of communication with each other is mounted in said partition wall;wherein said intake air-dispensing box is comprised of a dispensing box body which includes said intake air inlet, said first and second intake branch pipes and one of halves of said partition wall, said dispensing box body having an opening provided in its outer wall opposite from said first and second intake branch pipes to extend between said first and second dispensing chambers, and a lid detachably coupled to said dispensing box body to close said opening and having the other half of said partition wall, said lid being made of a light alloy by casting, and a valve bore permitting said first and second dispensing chambers to be put into communication with each other and bearing bores for supporting a valve shaft of said on-off valve for opening and closing said valve bore are defined in the other half of said partition wall, wherein said dispensing box body has one wall disposed proximal to said engine and another wall disposed opposite from said one wall, said first and second intake branch pipes being formed integrally with said one wall and disposed inside said dispensing box body while said opening is formed on said another wall.