초록 ▼

A sensor element responding to gases and/or vapors is heated in at least two temperature cycles continuously from a starting temperature value to an upper temperature value in accordance with a predetermined pattern which is optimized for selective gases. The temperature is lowered to the starting t

A sensor element responding to gases and/or vapors is heated in at least two temperature cycles continuously from a starting temperature value to an upper temperature value in accordance with a predetermined pattern which is optimized for selective gases. The temperature is lowered to the starting temperature value in accordance with the same or a different pattern. During the temperature cycles a signal which depends on the composition of the gas or vapor atmosphere delivered by the sensor element is compared in an electronic evaluation circuit to stored values which are characteristic for the presence of selective components in the gas and/or vapor.

대표청구항 ▼

A gas or vapor alarm system comprising: at least one heatable sensor element for generating an output signal in dependency upon the presence of a gas or vapor; heating means for continuously changing the temperature of said sensor element through at least two temperature cycles from a starting value

A gas or vapor alarm system comprising: at least one heatable sensor element for generating an output signal in dependency upon the presence of a gas or vapor; heating means for continuously changing the temperature of said sensor element through at least two temperature cycles from a starting value to an upper threshold value in accordance with a predetermined pattern and thereafter back to said starting value according to a preselected pattern, which patterns are optimized with respect to selective ones of said gases or vapors; said output signal of said sensor element varying during said temperature cycles as a function of the composition of said gas or vapor; an electronic circuit for receiving the output signals of the sensor element; and said electronic circuit comparing the variation of said output signal during said temperature cycle of said sensor element with stored ones of such variations which are characteristic for the presence of predetermined components of said gas or vapor.