Thermal flowmeter having a laminate structure
US6928865B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 8, 2004 |
| Grant date | Aug 16, 2005 |
| Priority date | — |
| Expiry date | Nov 8, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F5/00
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present invention relates to a thermal flowmeter capable of sensing a flow rate in either direction, having a linear output characteristic, and producing a stable output without impairing the response characteristic. In the thermal flowmeter, a laminate is fitted in a channel space formed in a body, forming a main channel. The laminate includes a mesh sheet so that a mesh portion is provided between the main channel and a sensor channel. A measurement chip is provided with an upstream temperature sensing resistor, a downstream temperature sensing resistor, a heating resistor, and a fluid temperature sensing resistor. By an electric circuit, the heating resistor and the fluid temperature sensing resistor are controlled to provide a constant temperature difference. Accordingly, the flow rate of a fluid under measurement is measured based on a temperature difference between the upstream and downstream temperature sensing resistors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.