| 摘要 |
PURPOSE:To prevent lowering of an output during high load running, by a method wherein, in an intake device in which a part of intake air in a cylinder is returned, an intake air return passage is formed such that the passage can be effectively-utilized as a part of an intake passage during high load running. CONSTITUTION:In a 4-cylinder engine 1, cylinders 2 are intercommunicated, and a return port 8 is formed as the one end of an intake air return passage 7 through which a part of intake air, fed in each cylinder through an intake passage 3, is returned to other cylinder 2 during a compression stroke. A communicating passage 27, through which the intake passage 3 open to each cylinder 2 and the intake air return passage 7 are intercommunicated at a portion in the vicinity of the cylinder 2, is provided, and a normally-closed rotary type electromagnetic on-off valve 28 is located in the communicating passage 27. Control is effected by a control device 31 in a manner that, during low load running of an engine 1, the electromagnetic on-off valve 28 is closed, an intake air return valve 17 is closed at a timing later than that of an intake port 4, meanwhile, during high load running, the electromagnetic on-off valve 28 is opened, and the closing timing of the intake air return valve 17 is advanced.
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