摘要:
A throttle body for an internal combustion engine, comprising a suction passage for supplying a suction air to the internal combustion engine; a throttle valve provided in the suction passage and fixed to a rotatable throttle valve shaft so as to adjust a quantity of the suction air; an interconnecting lever rotatably mounted to an interconnecting shaft and adapted to be rotated by pulling an accelerator cable; a throttle valve operating lever mechanically connected to the interconnecting lever and fixed to the throttle valve shaft, the throttle valve operating lever being rotated in predetermined relational association with rotation of the interconnecting lever to open and close the throtle valve; and a tension spring for normally biasing the throttle valve in a valve closing direction, the tension spring having one end or pivotal point fixed to a part fixed to the throttle body and the other end or operation point fixed to the throttle valve operating lever; wherein the pivotal point and the operation point are located at positions such that a distance from the throttle valve shaft to a line connecting the pivotal point and the operation point is gradually reduced as the throttle valve is opened, and a connection point between the interconnecting lever and the throttle valve operating lever is approached to a line connecting the throttle valve shaft and the interconnecting shaft as the throttle valve is opened.