Breath rate adjustment too sensitive

[kaiem]

In the current topology, adjustment of the breath rate is achieved by turning the control knob which changes the rate of vacuum bleed. Reducing the supply vacuum too much in this way increases sensitivity to pilot tube positioning and thereby reduces reliability.

[kaiem]

Suggest changing from bleed control to inline throttle in the output tube of the System Control Valve.

[kaiem]

Suggest adding a vacuum regulator in the source vacuum line to control the supply vacuum to a known value which would enable the rate adjustment knob position to be consistent and able to be calibrated against breathing rate.