GAS FLOW METER WITH HORIZONTAL PISTON MOVEMENT

A method and a gas flow meter for measuring gas flow. A cylinder is supported in the flow meter with a horizontal orientation. A piston is disposed movably within the cylinder, the piston having a surface which forms a clearance seal with a surface of the cylinder. The piston may have a low-friction coating such as diamond-like carbon. A gas flow to be measured is received at a gas inlet, and directed to the cylinder so as to move the piston within the cylinder. The gas flow is directed by valves and conduits alternately to the two ends of the cylinder, for measuring the gas flow in both directions of the cylinder. From the detected movement of said piston electrical signals representative of the gas flow are generated.