Patent ID: 7849737

Claim:
A gas meter comprising: a main flow path leading to a first flow path, a second flow path, and a third flow path which are provided in parallel by partitioning, along a direction of gas flow, a cross section of the main flow path through which the gas to be measured flows, the third flow path comprises a plurality of minute flow paths that are provided in parallel with flow path cross-sectional areas smaller than those of the first and second flow paths, wherein partial flows of the gas to be measured are generated on the first, second and third flow paths depend on the gas flow rate, the first and second flow paths having larger partial flow rates than the third flow path when the flow rate of the gas to be measured which flows in the main flow path is small, and the partial flow rates in the minute flow paths are increasing relative to the partial flow rates of the first and second flow paths when the flow rate of the gas to be measured, which flows through the main flow path, increases; a first flow rate sensor for measuring the flow rate, provided in the first flow path; second a flow rate sensor for measuring a leakage flow rate provided in the second flow path; a filter for flow baffling, provided in either one end or both ends of the first and second flow paths; and a contaminant-removing filter, provided at one end or both ends of the first flow path.