Patent ID: 7611472
Filing Date: 2009-11-03
Classification: A61B

Abstract:
1. A gas flow sensor used for apnea monitors, gas flow meters, and other industrial purposes comprises: 1) a sail as a gas flow sensing member mounted in an axle, around said axle said sail rotates, 2) a balance weight mounted in said axle, 3) a gossamer or spring connected to said axle with one end and connected to a case of said gas flow sensor with the other end for generating opposite torque against rotation of said sail, 4) a light path controller mounted in said axle to control the amount of light going from a light source to a light sensor, by partially or completely blocking the light while the position of said light path controller is changing, or by reflecting the light from said fight source to said light sensor while the angle of said light path controller is changing, 5) said light source mounted in said case in the proximity of said light path controller, on one side of said light path controller, and 6) said light sensor mounted in said case in the proximity of said light path controller: on the other side of said fight path controller, or on the same side of said light path controller with said light source, for generating output of said gas flow sensor.