Computer controllable multi-port valve

DETAILED DESCRIPTION This invention relates generally to multi-port fluid selection valves, and more particularly to an electrically operated valve for rapidly and precisely selecting one of a plurality of input ports.
The need often arises for a remotely controllable selector which will, on demand, become coupled to any one of a plurality of fluid conduits so that samples of the fluids may be drawn.
One very important requirement for such a valving system is in the medical equipment field for the analysis of the various gases in respiratory samples.
A relatively new medical technique involves the sampling of the gases in the airway of respiratory care patients.
A capillary conduit continuously carries a small sample to a mass spectrometer in order to determine the percentage of oxygen, carbon dioxide, nitrogen, etc.
, carried in the airway.
A sampling switch that couples an analyzer, such as a mass spectrometer, to any one of a plurality of input tubes containing a gas or fluid to be analyzed, must necessarily provide a tight seal against the introduction of contaminating gases into the system from adjacent tubes or surrounding environment, and the seal must be reliable so that there is little chance of wear and consequent leakage that may result from wiping friction between the moving switching selector and the various input ports of the valve.
Another important feature of an ideal switch is that it must have a minimum volume so that small selected samples can be directed into the analytical equipment without delay.
Briefly described, the present invention is for a selector valve having a platen provided on one surface with a centrally located output port and a plurality of input ports equally spaced and circumferentially positioned around the input port.
A selector manifold having a conduit adapted to interconnect a selected input port with the output ports is forcibly positioned against the opposite surface of the platen and resilient "0" rings at the conduit ends provide a secure seal between the conduit and the ports