Idling opening degree control apparatus in intake air control apparatus

An idling opening degree control apparatus in an intake air control apparatus in which an intake passage provided through in a control main body is opened and closed by a throttle valve attached to a throttle valve shaft rotatably pivoted to the control main body, comprising:

• a throttle valve lever (4) firmly fixed to a throttle valve shaft (3) and synchronously rotating with the throttle valve shaft (3);
• a loosely fitted lever (8) rotatably arranged in the throttle valve shaft (3) in a loose fit manner;
• a throttle valve operating drum (11) rotatably supported to a drum shaft (10) and operated so as to be opened and closed by a driver;
• and
• a cam lever (7) rotatably pivoted to a cam shaft (6) and rotating in correspondence to a movement in an axial direction of a lead screw type step motor (M),
• wherein said throttle valve operating drum and the loosely fitted lever (8) are coupled via a link lever (13),
• wherein an operating arm portion (4a) formed in said throttle valve lever is arranged so as to face to an opposing gap (S) between a first locking portion (8a1) and a second locking portion (8a2) in a forked locking portion (8a) formed in the loosely fitted lever (8) and a cam surface (7a) of the cam lever (7) is arranged so as to face to a roller (4b) provided in the throttle valve lever (4),
• wherein the operating arm portion (4a) of the throttle valve lever (4) is moved within the opposing gap (S) between the first locking portion (8a1) and the second locking portion (8a2) in the forked locking portion (8a) by the cam lever (7), thereby keeping an idling opening degree or a first idling opening degree of the throttle valve, at a time of operating the reed screw type stepping motor (M), and
• wherein the throttle valve is opened by bringing the first locking portion (8a1) of the loosely fitted lever (8) into contact with the operating arm portion (4a) of the throttle valve lever (4), at a time of operating the throttle valve operating drum (11) in an opening direction.