{HEAD ~ The second intake air passage} is opened by {TAIL ~ the opening and closing valve} when a first urging force, which acts onto the coiled spring while the interlocking member swings so as to interlock with the opening and closing valve being swung in an opening direction by a negative pressure exerted in the second intake air passage, is larger than a second urging force, which is exerted by a spring elasticity of the coiled spring 
{ HEAD ~ The second intake air passage } is opened by { TAIL ~ the opening and closing valve } when a first urging force , which acts onto the coiled spring while the interlocking member swings so as to interlock with the opening and closing valve being swung in an opening direction by a negative pressure exerted in the second intake air passage , is larger than a second urging force , which is exerted by a spring elasticity of the coiled spring
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH