US Patent 11835374 Ultrasonic mass fuel flow meter

The subject matter of this specification can be embodied in, among other things, a sensor that includes a first axial sensor housing portion having a first cross-sectional area, a second axial sensor housing portion arranged adjacent to the first axial sensor housing portion along the sensor axis and having a second cross-sectional area larger than the first cross-sectional area, and a face extending from the interior surface of the first axial sensor housing portion to the interior surface of the second axial sensor housing portion, a first buffer rod within the first axial sensor housing portion and having a first axial end and a second axial end, a second buffer rod within the second axial sensor housing portion and abutting the face, and having a third axial end and a fourth axial end, and an acoustic transceiver element acoustically mated to the second axial end and the third axial end.