Patent ID: 6332442
Filing Date: 2001-12-25
Classification: F02M,Y02T

Abstract:
An intake air duct serving as a passage for supplying air to an engine, the intake air duct comprising:a first intake air passage;a second intake air passage;an opening-and-closing valve swingably disposed in said second intake air passage so as to open and close said second intake air passage;an interlocking member swingably disposed outside said first intake air passage and said second intake air passage such that swinging of the opening-and-closing valve results in the swinging of the interlocking member; anda coiled spring disposed swingably outside said first intake air passage and said second intake air passage, and having a swinging end brought into contact with a surface of said interlocking member, the swinging end sliding on a surface of said interlocking member during the swinging of said interlocking member;said second intake air passage being opened by said opening-and-closing valve when a first urging force, which acts onto said coiled spring, is larger than a second urging force, which is exerted by a spring elasticity of said coiled spring, and being closed when the first urging force is smaller than the second urging force, and/said first urging force results from a negative pressure exerted in said second intake air passage applied to the opening-and-closing valve causing said opening-and-closing valve swinging in the opening direction, and further causing the swinging of the interlocking member.