Patent ID: 8261725

Claim:
A low pressure EGR apparatus for an engine comprising: a low pressure EGR passage for re-circulating a part of exhaust gas from the engine into a low negative pressure portion of an intake-air passage of the engine as EGR gas; a low pressure EGR control valve provided in the low pressure EGR passage for controlling EGR gas amount by adjusting an opening degree of the low pressure EGR control valve; an intake-air valve provided in the intake-air passage at an upstream side of a connecting portion between the low pressure EGR passage and the intake-air passage, for controlling intake-air amount by adjusting an opening degree of the intake-air valve; an actuator for driving the low pressure EGR control valve; and a link device having a converting mechanism for converting an output characteristic of the actuator, wherein the link device drives the intake-air valve by an output converted through the converting mechanism, wherein the low pressure EGR apparatus controls EGR amount depending on a rotational direction of the intake-air valve from its maximum valve opening position to a valve closing position as well as a rotational direction of the low pressure EGR control valve from its maximum valve closing position to a valve opening position, the low pressure EGR control valve controls the EGR amount by changing its rotational angle, the intake-air valve controls negative pressure generated at a downstream side of the intake-air valve by changing its rotational angle, valve supporting shafts for the low pressure EGR control valve and the intake-air valve are arranged in parallel to each other, the link device has a cam plate rotating together with the low pressure EGR control valve and an arm rotating together with the intake-air valve, wherein the cam plate and the arm are operatively connected with each other via the converting mechanism, and the cam plate and the arm are respectively fixed to the valve supporting shafts for the cam plate and the arm at right angle.