Flow path sensing for flow therapy apparatus

Abstract

A respiratory flow therapy apparatus including a sensing chamber which measures a flow of gases provided to a patient. The sensing chamber can be located after a blower and/or mixer. The sensing chamber can include an ultrasonic transducer, a temperature sensor, a heated temperature sensing element, and/or a gas concentration sensor. A flow path of gases used in conjunction with the sensor system prevents unwanted vorticity in the flow of gases that can create anomalies in measuring flow.

1 - 47 . (canceled) 
     
     
         48 . A sensing chamber in a flow therapy apparatus, the sensing chamber comprising:
 one or more sensors configured to measure gases properties of a gases flow, wherein the one or more sensors include a first ultrasonic transducer at a downstream portion of a flow path and a second ultrasonic transducer at an upstream portion of the flow path; and   a heated temperature sensing element configured to measure a gases flow rate.   
     
     
         49 . The sensing chamber of  claim 48 , wherein the first and second ultrasonic transducers and the heated temperature sensing element are configured to provide a redundancy of the gases flow rate measurement, the redundancy comprising a faster flow measurement at low gases flows by the first and second ultrasonic transducers and a more accurate flow measurement at the low gases flows by the heated temperature sensing element. 
     
     
         50 . The sensing chamber of  claim 49 , wherein the redundancy is configured to assist with calibration for a flow rate. 
     
     
         51 . The sensing chamber of  claim 48 , wherein the heated temperature sensing element is configured to adjust a calibration parameter of the first and second ultrasonic transducers or readings of the first and second ultrasonic transducers. 
     
     
         52 . The sensing chamber of  claim 51 , wherein the adjustment is a continuous adjustment. 
     
     
         53 . The sensing chamber of  claim 51 , wherein the adjustment is by a predetermined amount, rate, or weighted on flow rate or other sensed parameters. 
     
     
         54 . The sensing chamber of  claim 48 , wherein at least one of the one or more sensors are located in a sensor module. 
     
     
         55 . The sensing chamber of  claim 48 , wherein the flow path, is configured to mixed gases from a blower and direct the gases flow through the sensing chamber. 
     
     
         56 . The sensing chamber of  claim 48 , further comprising a sensing circuit board, wherein a first portion of the sensing circuit board is positioned at least partially within the flow path. 
     
     
         57 . The sensing chamber of  claim 48 , wherein the gases flow is measured through a portion of the flow path configured to be continuously curved such that there are no significant angles. 
     
     
         58 . The sensing chamber of  claim 48 , wherein the flow path comprises an entrance, a horizontal portion, and an exit, wherein the entrance and the exit are positioned in vertically opposed directions when in use, and the horizontal portion is positioned between the entrance and the exit. 
     
     
         59 . The sensing chamber of  claim 58 , wherein the horizontal portion has a smooth curve along the horizontal portion. 
     
     
         60 . The sensing chamber of  claim 55 , further comprising a main housing, and a motor module comprising the blower, wherein the motor module is received by a recess in the flow therapy apparatus. 
     
     
         61 . The sensing chamber of  claim 60 , wherein the recess is gas impermeable and unbroken, other than the flow path. 
     
     
         62 . The sensing chamber of  claim 60 , wherein the main housing comprises a main housing upper chassis and a main housing lower chassis. 
     
     
         63 . The sensing chamber of  claim 62 , wherein the main housing lower chassis is attachable to the main housing upper chassis. 
     
     
         64 . The sensing chamber of  claim 63 , wherein the main housing lower chassis is attachable to the main housing upper chassis either by suitable fasteners or integrated attachment features. 
     
     
         65 . The sensing chamber of  claim 64 , wherein the recess comprises a recess opening provided in a bottom wall of the main housing lower chassis, for receipt of the motor module, a continuous, gas impermeable, unbroken peripheral wall being integrally formed with the bottom wall of the main housing lower chassis and extending upwardly from a periphery of the recess opening. 
     
     
         66 . The sensing chamber of  claim 48 , wherein the first and second ultrasonic transducers are further configured to determine a gas concentration. 
     
     
         67 . The sensing chamber of  claim 56 , wherein the one or more sensors further comprise a temperature sensor configured to measure a temperature of the gases flow in the flow path, and wherein the sensing circuit board is configured to affect thermal conduction between the gases flow in the flow path and the temperature sensor, and impede thermal conduction between a wall of the sensing chamber and the temperature sensor. 
     
     
         68 . The sensing chamber of  claim 56 , wherein the sensing circuit board comprises at least a second portion of the sensing circuit board configured to be positioned outside the flow path of the sensing chamber. 
     
     
         69 . The sensing chamber of  claim 68 , further comprising a seal dividing the first portion of the sensing circuit board from the second portion of the sensing circuit board.