Contamination removal from sensors placed in an airway

Abstract

A sensor assembly includes a sensing element and an actuator. The sensing element measures a parameter associated with gas in an airway. The actuator actuates the sensing element to prevent contamination build up on the sensing element.

1 .- 31 . (canceled) 
     
     
         32 . A sensor assembly for positioning in a breathing tube of a patient circuit, comprising:
 a sensing element having a first end, a second end, and including one of a resistive or a capacitive sensing element;   an actuator having a first layer and a second layer;   wherein the first end protrudes into an airway path of the breathing tube for sensing a relative humidity of the gas within the breathing tube, and the second end is affixed between the first layer and the second layer; and   the first layer and the second layer are configured to receive an oscillating drive signal that drives mechanical movement of the sensing element.   
     
     
         33 . The sensor assembly of  claim 32 , wherein a vane is positioned between the first layer and the second layer of the actuator, wherein the sensing element is mechanically coupled to a printed circuit board coupled to the vane such that the sensing element is positioned to protrude into the airway path. 
     
     
         34 . The sensor assembly of  claim 33 , wherein the vane, the printed circuit board, and the sensing element are parallel to a plane between the first layer and the second layer of the actuator. 
     
     
         35 . The sensor assembly of  claim 32 , wherein a first connector is electrically coupled to the sensing element and configured to provide a measurement signal indicative of the sensed humidity. 
     
     
         36 . The sensor assembly of  claim 32 , wherein a second connector is electrically coupled to the actuator and configured to provide a drive signal to the actuator to actuate the sensing element. 
     
     
         37 . The sensor assembly of  claim 32 , wherein the sensing element is further configured to measure a temperature within the breathing tube. 
     
     
         38 . The sensor assembly of  claim 32 , wherein the sensing element is maintained in a sensing element housing. 
     
     
         39 . The sensor assembly of  claim 32 , wherein the first layer and the second layer of an actuator comprise a piezoelectric material. 
     
     
         40 . The sensor assembly of  claim 32 , wherein the drive signal is configured to drive the actuator at a resonant frequency. 
     
     
         41 . The sensor assembly of  claim 32 , wherein actuator is enclosed by a seal in the airway of the breathing tube such that the sensing element protrudes from the seal. 
     
     
         42 . The sensor assembly of  claim 32 , wherein the printed circuit board is electrically coupled to the sensing element and the first connector. 
     
     
         43 . A method of providing improved accuracy, reliability and/or repeatability of dosage for a respiratory therapy session, comprising:
 positioning a sensing element such that a first end of the sensing element is positioned to protrude into an airway path of the breathing tube and a second end of the sensing element is affixed between a first layer and a second layer of an actuator, wherein the sensing element includes one of a resistive or a capacitive sensing element for sensing a relative humidity of a gas in the airway path; and   driving mechanical movement of the sensing element by providing an oscillating drive signal to the actuator to reduce contamination on the sensing element.   
     
     
         44 . The method of  claim 43 , wherein the sensing element is further configured to measure a temperature within the airway. 
     
     
         45 . The method of  claim 43 , wherein the first layer and the second layer are formed of piezoelectric layers. 
     
     
         46 . The method of  claim 45 , wherein the sensing element is affixed to the actuator through a vane that is positioned between the first layer and the second layer. 
     
     
         47 . The method of  claim 46 , wherein the vane forms a u-shaped channel. 
     
     
         48 . The method of  claim 43 , wherein the drive signal is configured to drive the actuator at a resonant frequency. 
     
     
         49 . The method of  claim 43 , wherein actuator is enclosed by a seal in the airway of the breathing tube such that the sensing element protrudes from the seal.