Throttles

A throttle comprising:

• a throttle body having an air intake passage,
• a throttle shaft rotatably supported by the throttle body and having a rotational axis l,
• a throttle valve disposed on the throttle shaft and adapted to open and close the intake air passage,
• a relief lever pivotally mounted on the throttle shaft,
• a return spring disposed between the throttle body and the relief lever and adapted to urge the relief lever in a valve closing direction with respect to the throttle body,
• a throttle gear fastened to the throttle shaft,
• a relief spring disposed between the throttle gear and the relief lever and adapted to urge the throttle gear in a valve opening direction with respect to the relief lever,
• first contact means provided on the throttle gear and the relief lever, wherein the throttle gear contacts the relief lever when the throttle gear pivots to a predetermined pivot position B in the valve opening direction and
• second contact means provided on the throttle body and the relief lever, wherein the throttle body contacts the relief lever when the relief lever pivots to the predetermined pivot position B in the valve closing direction, wherein a first contact position of the first contact means and a second contact position of the second contact means are both located either (i) within a plane P that is perpendicular to the rotational axis L of the throttle shaft or (ii) on the same side of the plane P, and wherein the plane P includes a position in which the biasing force of the return spring acts on the relief lever.

A throttle comprising:

• a throttle body 1 having an air intake passage 1a,
• a throttle shaft 2 rotatably supported by the throttle body 1 and having a rotational axis L,
• a throttle valve 13 disposed on the throttle shaft 2, the throttle valve 13 opening and closing the intake air passage 1a based upon rotation of the throttle shaft 2,
• a relief lever 9 pivotally mounted on the throttle shaft 2, the relief lever 9 comprising a projection 9d,
• a return spring 11 urging the relief lever 9 in a valve closing direction with respect to the throttle body 1,
• a throttle gear 5 fastened to the throttle shaft 2, the throttle gear comprising a pin 5b,
• a relief spring 10 urging the throttle gear 5 in a valve opening direction with respect to the relief lever 9,
• an adjustment screw 12 threadably engaging the throttle body 1,
• a control motor 3 and
• a gear mechanism (3a, 4) disposed between the control motor 3 and the throttle gear 5, wherein the gear mechanism (3a, 4) transmits torque from the control motor 3 to the throttle shaft 2,
• wherein the pin 5b contacts the projection 9d at a first contact position 20A when the throttle gear 5 pivots to a predetermined pivot position B in the valve opening direction and
• wherein the adjustment screw 12 contacts the projection 9d at a second contact position 20B when the relief lever 9 pivots to the predetermined pivot position B in the valve closing direction, wherein the first contact position 20A and the second contact position 20B are both located either (i) within a plane P that is perpendicular to the rotational axis L of the throttle shaft 2 or (ii) on the same side of the plane P, wherein the plane P includes a position in which the biasing force of the return spring 11 acts on the relief lever 9, and wherein the position of the relief lever 9 is prevented from tilting as a result of the relief lever 9 moving to the predetermined pivot position B from (i) the valve closing direction or (ii) the valve opening direction.