Patent ID: 6561160
Filing Date: 2003-05-13
Classification: F02D

Abstract:
A rotary-body type throttle valve for a spark ignition internal combustion engine comprising:a valve casing having an interior; an upstream intake passage and a downstream intake passage; an intake passage formed within said interior and having a rotary-body recess portion formed within said intake passage and having an axis line intersecting a central axis of said intake passage; a valve element having a rotary-body shape rotatably fitted into said rotary-body recess portion of said valve casing; a communication passage provided between said upstream and downstream intake passages, said upstream intake passage and said downstream intake passage sandwiching said rotary-body recess portion; and a through hole formed in a first rotary outer surface of said valve element, said through hole directed from said communication passage of said valve element in a direction intersecting the central axis of said communication passage and penetrating said first rotary outer surface of said valve element, wherein a dimension of said through hole as measured with respect to a circumferential direction of said valve-element is set between &frac13; to &frac23; of a diameter of said intake passage.