Patent ID: 8555637

Claim:
An air supply pipe comprising: a curved pipe portion formed in a tubular shape, the curved pipe portion including a first end, a second end and a rectangular pipe portion communicated with the first end and the second end; a first straight pipe portion formed in a cylindrical shape, the first straight pipe portion having a first outer diameter, the first straight pipe portion extending from the first end along a first direction; and a second straight pipe portion formed in a cylindrical shape, the second straight pipe portion having a second outer diameter, the second straight pipe portion extending from the second end along a second direction intersecting with the first direction, wherein a cross-sectional shape of the rectangular pipe portion in a cutting plane perpendicular to a center axis of the curved pipe portion is a rectangular shape having longer sides in a third direction perpendicular to the first direction and the second direction, an outer edge of the first end viewed from the third direction is bent at a first curvature radius, and an outer edge of the second end viewed from the third direction is bent at a second curvature radius different from the first curvature radius.