Patent ID: 7891239

Claim:
A flow meter for measuring the flow of a measurement fluid, comprising: a flow path wherein the measurement fluid flows; a flow rectifier disposed within the flow path; a flow path block having a flow path forming portion that extends in the form of a straight line so as to form a flow path, provided therein, and an opening portion connecting between above the flow path forming portion and the outside; and a cover member disposed so as to cover the opening portion of the flow path block, wherein: the flow rectifier has a hole rectifying the flow of the measurement fluid, and a cross-sectional area that is wider than the cross-sectional area of the flow path in a direction that is perpendicular to the direction in which the flow path extends, the flow rectifier has at least one flow rectifying plate that is disposed at an incline relative to the direction it which the flow path extends, the flow rectifying plate is disposed with the outer peripheral surface thereof in contact around the entire periphery of the inner wall of the flow path, the flow path is a straight pipe-shaped flow path that is formed by the opening member covering the opening portion of the flow path block; and when the cover member covers the opening portion of the flow path block, the outer peripheral surface of the flow rectifying plate contacts the cover member, and the outer peripheral surface of the flow rectifying plate contacts the inner wall of the flow path block, so that the flow rectifying plate is secured and held between the cover member and the inner wall of the flow path block.