Patent ID: 9459199
Filing Date: 2016-10-04
CPC Classification: G01N

Claim Text:
1. A device for sensing humidity in a stream of process gas, comprising: elongate cylindrical barrel constituting a main body of the device, said barrel including a process gas inlet port and an outlet port, said outlet port being in fluid communication with said inlet port through a filtration duct, said ports located within the process gas stream so as to conduct a continuous flow of a slip stream of said process gas stream past a humidity sensor; a filtration assembly comprising a filter defining an enclosed internal volume housing the humidity sensor, said assembly providing said sensor with a protective barrier against contact with solid matter within said process slip stream; a source of purge gas; a purge gas conditioning chamber within said barrel partially defined by a sidewall thereof, said chamber being so disposed as to receive a flow of purge gas originating from said source at a first end and to equalize the purge gas temperature and humidity approximately with the process gas stream by direct contact between the purge gas and the slip stream gas; and valve means for discharging said purge gas from a second end of said conditioning chamber into said filter internal volume thereby reversing the gas flow direction through the filter to clean the outer surface of the filter.