Physical quantity measuring device

Abstract

A physical quantity measuring device includes a flow channel body, a flow rate measuring unit, an upstream opening, a downstream opening, and a sub-flow channel. The flow channel body includes a main flow channel. The flow rate measuring unit is disposed in the main flow channel. The upstream opening is disposed in upstream of the main flow channel. The downstream opening is disposed in downstream of the main flow channel. The sub-flow channel is disposed in outside the main flow channel to connect the upstream opening and the downstream opening to each other. The sub-flow channel has a constriction portion that reduces a cross-sectional area of the flow channel.

Dependencies are inferred from the claim text.