US 11,980,719 B2
Humidified gases delivery apparatus and methods for controlling same
Alastair Edwin McAuley, Auckland (NZ); Yi-Cheng Sun, Auckland (NZ); and Jonathan David Harwood, Auckland (NZ)
Assigned to Fisher & Paykel Healthcare Limited, Auckland (NZ)
Filed by Fisher & Paykel Healthcare Limited, Auckland (NZ)
Filed on Aug. 24, 2021, as Appl. No. 17/445,808.
Application 15/261,046 is a division of application No. 13/517,405, granted, now 9,440,042, issued on Sep. 13, 2016, previously published as PCT/NZ2010/000263, filed on Dec. 23, 2010.
Application 17/445,808 is a continuation of application No. 16/252,339, filed on Jan. 18, 2019, granted, now 11,129,957.
Application 16/252,339 is a continuation of application No. 15/261,046, filed on Sep. 9, 2016, granted, now 10,220,177, issued on Mar. 5, 2019.
Claims priority of provisional application 61/289,512, filed on Dec. 23, 2009.
Prior Publication US 2022/0040439 A1, Feb. 10, 2022
Int. Cl. A61M 16/16 (2006.01); A61M 16/00 (2006.01); A61M 16/04 (2006.01); A61M 16/06 (2006.01); A61M 16/08 (2006.01); A61M 16/10 (2006.01); A61M 16/12 (2006.01); G01F 23/22 (2006.01)
CPC A61M 16/16 (2013.01) [A61M 16/0051 (2013.01); A61M 16/0066 (2013.01); A61M 16/024 (2017.08); A61M 16/04 (2013.01); A61M 16/0666 (2013.01); A61M 16/0833 (2014.02); A61M 16/0875 (2013.01); A61M 16/104 (2013.01); A61M 16/109 (2014.02); A61M 16/1095 (2014.02); A61M 16/12 (2013.01); A61M 16/161 (2014.02); G01F 23/22 (2013.01); A61M 2016/0039 (2013.01); A61M 2205/18 (2013.01); A61M 2205/3368 (2013.01); A61M 2205/3379 (2013.01); A61M 2205/3386 (2013.01); A61M 2205/502 (2013.01); A61M 2205/52 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method of electronically determining a water level in a chamber within a humidified gases delivery system configured to provide humidified respiratory gases to a user in a respiratory treatment, wherein water in the chamber is configured to humidify the respiratory gases, the method comprising:
using an electronic controller of the system:
determining an evaporation rate of the water in the chamber during the respiratory treatment;
determining a current water level based at least in part on the evaporation rate;
determining a remaining treatment time of the respiratory treatment; and
based at least in part on the evaporation rate, the current water level, and the remaining treatment time:
calculating a remaining time that humidity can be provided to the respiratory gases by the water in the chamber so as to determine whether the current water level can last the remaining treatment time, and
upon determining that the current water level cannot last the remaining treatment time, adjusting control of power supplied to a heater plate of the system so as to prolong a time period when the respiratory gases are humidified by the current water level while providing at least a minimum amount of humidification to the respiratory gases, wherein the heater plate is powered to heat up the water in the chamber to create water vapor.