Method for measuring the flow rate of a medium flowing through a pipe and apparatus therefor
US4669301A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 14, 1986 |
| Grant date | Jun 2, 1987 |
| Priority date | — |
| Expiry date | Mar 14, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F1/72
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus are disclosed for measuring the flow rate of a medium flowing through a pipe. The invention is particularly for measuring the rate of air flow in the intake pipe of an internal combustion engine by means of a throughput sensor which is insensitive to the direction of flow. The throughput sensor can be a constant-temperature anemometer. The analog output signals of the sensor are converted into a sequence of discrete numerical values with an adjustable sampling rate, wherein the periodic output signal characteristic of the flow meter is weighted for determining the occurrence of changes in the direction of flow, and wherein the duration of time in which the direction of flow is changed is considered in the determination of the flow rate via corresponding correction factors. In the method and apparatus of the invention, the points in time at which changes in the direction of flow occur are determined according to the following steps: (a) comparing the differential values of successive numerical values of the number sequence with a first threshold value particularly dependent on the sampling rate; (b) determining the characteristic time points at which the first…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.