Sensor arrangement for measuring the mass of a flowing fluid
US5817933A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 27, 1996 |
| Grant date | Oct 6, 1998 |
| Priority date | — |
| Expiry date | Aug 27, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F1/684
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A film sensor element is used to determine the mass of a flowing fluid, in particular an air mass flow in the intake tube of an internal combustion engine. Such a sensor is part of a measurement bridge and operates on the hot-wire anemometer principle, designed as a constant-resistance regulator connected to an operational amplifier. To reduce the response time, two separate resistance tracks of a film sensor element are structured in such a way that they are situated perpendicular to the direction of flow (S) with one track (6) along the leading edge and the other track (7) along the trailing edge. The tracks (6, 7) are electrically connected in parallel, such that the current can be divided according to the two resistance values as a current divider. Consequently, if the conductive track at the leading edge of the current divider cools to a greater extent this is counteracted by the rising current in the conductive track at the leading edge and thus greater electrical power is applied to the track at the leading edge. This is particularly advantageous in dual sensors for detecting the flow direction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.