Patent · US Expired

Boiling alarm

US4673925A · kind A · utility

9Cited by
3References
9Claims
0Family size

Inventor

Key dates

Filing dateOct 26, 1984
Grant dateJun 16, 1987
Priority date
Expiry dateOct 26, 2004

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05D23/27543
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A boiling sensor includes a case, which is mounted on the upper edge of a container in which liquid is to boil. A pair of electrical probes are spaced apart a small distance and mounted on the case above the liquid. Behind the probes is a collector of the material, preferably sheet nylon, which does not absorb the liquid, which is non-wettable and electrical insulative, and which has a high heat capacity. With a high heat capacity, the vapor raises the temperature of the collector slowly so that vapor continues to condense on the collector between the probes. The probes are part of an electrical circuit. The condensed water vapor allows current to flow the between the probes, and the rest of the circuit causes current to flow through a sound or visual indicator to indicate that the water is boiling. This circuit also has a voltage divider, one side of which is the electrical probe, and by adjusting the resistance on the other side of the voltage divider, the sensitivity of the circuit can be controlled. In another embodiment the probes are a metal plate and a screw which extends into the case but which is electrically insulated by a nylon bushing. The bushing acts as the vapor coll…

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