Patent · US Expired

Calorimetric flow monitor

US4028689A · kind A · utility

20Cited by
9References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 18, 1975
Grant dateJun 7, 1977
Priority date
Expiry dateSep 18, 1995

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R17/10
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A calorimetric flow monitor comprising a measuring head adapted to be connectable to a pipe carrying a flow medium. The measuring head includes two thermistors, one of which is surrounded by a heating coil to be heated thereby. The unheated thermistor and the heatable thermistor together with its heating coil are mounted in a pair of pins protruding from the measuring head. The thermistors are connected in an electrical bridge circuit. A first differential amplifier for determining increases and decreases in the flow of the medium relative to a preset flow is connected to the bridge circuit. Visual indicating devices are optionally provided to indicate when the flow is above and below the preset flow. A second differential amplifier for monitoring the occurrence of breakages in conductors connected to the thermistors and the heating coil, is also connected to the bridge circuit.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.