Air intake device for internal combustion engine

An air intake device for an internal combustion engine, comprising:

• an air intake path through which intake air flows;
• a throttle valve provided in the air intake path and comprising:
• a valve shaft rotatable relative to the air intake path;
• and
• a valve body having a plate shape and connected to the valve shaft to open and close the air intake path, the valve body including a first end and a second end, the first end moving to an upstream side of the air intake path when the valve body rotates to open the air intake path, the second end moving to a downstream side of the air intake path when the valve body rotates to open the air intake path;
• and
• a first partition plate disposed approximately parallel to a flow direction of the intake air and including opposite ends connected to a first inner wall surface of the air intake path closer to the first end than the second end, the first partition plate having a substantially curved convex shape protruding radially inward of the air intake path, the first partition plate having the opposite ends connected to the first inner wall surface at locations downstream of the first end of the valve body,
• wherein a first air flow path is defined between the first partition plate and the first inner wall surface of the air intake path.