Miniature sensor for mainstream capnometry/capnography instrumentation

Claim 1

A miniature IR sensor for use in main-stream Capnometry/Capnography instrumentation, comprising: (a) a breathing tube; (b) an assembly including a first inlet port, a second exit port, and a third port in said assembly, said third port arrayed in and through a wall portion of said assembly and communicating with said first inlet port and second exit port, said assembly attached in series with said breathing tube carrying breathing gases for evaluation by said miniature IR sensor; (c) a partially circular cutout portion in said assembly fitting onto and into said breathing tube and providing a substantially air tight connection therewith; (d) a sampling cell formed interior of said assembly; (e) a source of infra-red radiation mounted at a first end of the sampling cell, said infra-red source arrayed for passing said radiation into said sampling cell; (f) an infra-red detector means mounted at a second end of said sampling cell, said second end distal and opposite said first end, said infra-red detector means for detecting said radiation emerging from the sampling cell; (g) a valve member mounted integrally within said assembly, said valve member arrayed immediately adjacent a wall of said sampling cell, said valve member including: (g1) said first inlet port for fluidly connecting a source of calibrating gases with the sampling cell; (g2) said second exit port for fluidly connecting said sampling cell with an exhausting means for exhausting said calibrating gases; (g3) a plurality of elongated passageways fluidly connecting said breathing gases in said breathing tube with said sampling cell; (g4) an extended portion means of said valve member moving said valve member from a first normal operating position to a second calibrating position; (h) an actuating means for engaging said extended portion means of said valve member, said actuating means arranged for selectively moving said extended portion means and valve member between said first normal operating position and said second calibrating position; said first normal operating position allowing only the breathing gases carried in said breathing tube to enter said sampling cell, and said second calibrating position allowing said calibrating gases to enter said sampling cell and excluding said breathing gases from entering said sampling cell, said second calibrating position allowing said calibrating gases to be exhausted from said sampling cell.