AIR FLOW RATE MEASUREMENT DEVICE FOR MEASURING AIR FLOW RATE WITH HIGH SENSITIVITY AND PRECISION

摘要

PURPOSE: An air flow rate measurement device is provided to improve the flow rate detection sensitivity, to stabilize flow rate signals, to suppress the influence of water drops and dust, and to secure the high flow rate measurement precision by stably and massively inducing air into a branch passage. CONSTITUTION: An air flow rate measurement device includes a branch passage(4). The branch passage consists of an upper branch passage(5) and a lower branch passage(6) which are communicated with each other via a curved part(7). The branch passage is formed in the shape of an inverted U. An inflow port(8) is formed by removing the upper wall in the main stream direction of the upper branch passage and removing both sidewalls orthogonal to the extension direction of a detecting flow pipe(3). The lower wall in the main stream direction of the upper branch passage is displaced upward to form an air induction face(11).