Patent ID: 7762653

Claim:
A tube for supplying a fluid therethrough comprising: a base wall part, from the viewpoint of the cross section perpendicular to a longitudinal direction of the tube, having a region provided outside a first closed line segment, which defines an inside of the inner surface of the tube, and inside a second closed line segment, whose shape is similar to a shape of the first closed line segment and which encloses the first closed line segment, where a gravity center of the second closed line segment is coincident with a gravity center of the first closed line segment; and an enlarged wall part, from the viewpoint of the cross section perpendicular to the longitudinal direction of the tube, having a region provided outside the second closed line segment and inside a third closed line segment which encloses the second closed line segment; wherein a shape of the third closed line segment is similar to the shape of the second closed line segment and a gravity center of the third closed line segment is different from the gravity center of the second closed line segment.