Patent Publication Number: US-2022211964-A1

Title: Conduit for respiratory therapy apparatus

Description:
CROSS REFERENCE 
     This application is a continuation of U.S. application Ser. No. 16/347,855, filed on May 7, 2019, which is a national phase entry under 35 U.S.C. § 371 of International Application No. PCT/AU2017/051219 filed Nov. 6, 2017, published in English, which claims priority from U.S. Provisional Patent Application No. 62/418,374 filed Nov. 7, 2016, all of which are incorporated herein by reference. 
    
    
     FIELD OF THE TECHNOLOGY 
     The present technology relates to apparatus for breathable gas therapy for respiratory conditions such as the conditions related to obstructive sleep apnea (OSA), sleep disordered breathing (SDB), allergy induced upper airway obstruction or early viral infection of the upper airway, among others. More particularly, the technology involves improvements related to delivery conduit components for such respiratory treatment apparatus. 
     BACKGROUND OF THE TECHNOLOGY 
     Sleep is important for good health. Frequent disturbances during sleep or sleep fragmentation can have severe consequences including day-time sleepiness (with the attendant possibility of motor-vehicle accidents), poor mentation, memory problems, depression and hypertension. For example, a person with nasal congestion may snore to a point that it disturbs that person&#39;s ability to sleep. Similarly, people with Obstructive Sleep Apnea (OSA) are also likely to disturb their partner&#39;s sleep. The best form of treatment for patients with OSA is Continuous Positive Airway Pressure (CPAP) applied by a flow generator such as a blower (or compressor) via a connecting delivery hose with a patient interface. 
     CPAP therapy has been used to treat OSA. The continuous positive airway pressure acts as a pneumatic splint and may prevent upper airway occlusion, such as by pushing the soft palate and tongue forward and away from the posterior oropharyngeal wall. Treatment of OSA by CPAP therapy may be voluntary, and hence patients may elect not to comply with therapy if they find devices used to provide such therapy one or more of uncomfortable, difficult to use, expensive or aesthetically unappealing. 
     Non-invasive ventilation (NIV) provides ventilatory support to a patient through the upper airways to assist patient breathing and/or maintain adequate oxygen levels in the body by doing some or all of the work of breathing. The ventilatory support is provided via a non-invasive patient interface. NIV has been used to treat OSA, respiratory failure, and periodic breathing. In some forms, the comfort and effectiveness of these therapies may be improved. 
     Such positive airway pressure may be delivered in many forms. For example, a positive pressure level may be maintained across the inspiratory and expiratory levels of the patient&#39;s breathing cycle at an approximately constant level. Alternatively, pressure levels may be adjusted to change synchronously with the patient&#39;s breathing cycle. For example, pressure may be set at one level during inspiration and another lower level during expiration for patient comfort. Such a pressure treatment system may be referred to as bi-level. Alternatively, the pressure levels may be continuously adjusted to smoothly replicate changes in the patient&#39;s breathing cycle. A pressure setting during expiration lower than inspiration may generally be referred to as expiratory pressure relief. As described by Sullivan in U.S. Pat. No. 4,944,310, positive airway pressure treatments typically provide gas under pressures to the patient in the range of 4 to 15 cmH 2 O from the device and may involve flow rates of up to about 120 liters/minute. Some of the air may escape via an end restriction or vent and not be delivered to the patient. These pressure settings may also be adjusted based on the detection of conditions of the patient&#39;s airway. For example, treatment pressure may be increased in response to the detection of partial obstruction, apnea, hypopnea or snoring, etc. 
     Other devices are known for providing respiratory tract therapy. For example, Schroeder et al. describes an apparatus for delivering heated and humidified air to the respiratory tract of a human patient in U.S. Pat. No. 7,314,046. Similarly, Genger et al. discloses an anti-snoring device with a compressor and a nasal air cannula in U.S. Pat. No. 7,080,645. 
     A typical system of the present technology may include a respiratory therapy device, such as a Respiratory Pressure Therapy Device (RPT device), an air circuit, a humidifier, and a patient interface. 
     Patient Interface 
     A patient interface may be used to interface respiratory equipment to its user, for example by providing a flow of air to an entrance to the airways. The flow of air may be provided via a mask to the nose and/or mouth, a tube to the mouth or a tracheostomy tube to the trachea of the user. Depending upon the therapy to be applied, the patient interface may form a seal, e.g., with a face region of the patient, to facilitate the delivery of gas at a pressure at sufficient variance with ambient pressure to effect therapy, e.g., a positive pressure of about 10 cmH 2 O. For other forms of therapy, such as the delivery of oxygen, the patient interface may not include a seal sufficient to facilitate delivery to the airways of a supply of gas at a positive pressure of about 10 cmH 2 O. 
     Different types of patient interfaces may be known by a variety of names by their manufacturer including nasal cannulas, nasal masks, full-face masks, nasal pillows, nasal puffs and oro-nasal masks. 
     Air Circuit 
     An air circuit, such as one or more conduits, may pneumatically couple between a flow generator and a patient interface, to transfer breathable gas (e.g., air and/or oxygen) between the devices. The air circuit may be referred to as an air delivery tube or a delivery conduit. In some cases there may be separate limbs of the circuit for inhalation and exhalation. In other cases a single limb is used. 
     Respiratory Pressure Therapy (RPT) Device 
     One known RPT device used for treating sleep disordered breathing is the S9 Sleep Therapy System, manufactured by ResMed. Another example of an RPT device is a non-invasive ventilator. 
     RPT devices typically comprise a pressure or flow generator, such as a motor-driven blower (e.g., a servo controlled motor and impeller in a volute) or a compressed gas reservoir, and are configured to supply a flow of air to the airway of a patient. In some cases, the flow of air may be supplied to the airway of the patient at positive pressure. The outlet of the RPT device is connected via the air circuit the patient interface such as those described above. An RPT device may be referred to as a respiratory therapy device herewithin. 
     Humidifier 
     Delivery of a flow of air without humidification may cause drying of airways. The use of a humidifier with a RPT device and the patient interface produces humidified gas that minimizes drying of the nasal mucosa and increases patient airway comfort. In addition in cooler climates, warm air applied generally to the face area in and about the patient interface is more comfortable than cold air. A range of artificial humidification devices and systems are known, however they may not fulfill the specialised requirements of a medical humidifier. 
     Respiratory humidifiers are available in many forms and may be a standalone device that is coupled to an RPT device via an air circuit, integrated with the RPT device or configured to be directly coupled to the relevant RPT device. 
     There is a desire for improved exchange of information between components of a respiratory therapy system with each other, and with the user. Operation of the respiratory therapy system as a whole may be improved as a result, as may the resulting therapy provided to the user, such as in terms of comfort, quality of therapy and/or compliance. 
     Furthermore, it may be desirable to introduce additional functionalities to components, for example to interact with other components of a respiratory therapy system, with the user, or in a standalone capacity. Prior solutions for communication within components of respiratory therapy systems may be inconvenient, difficult to use or expensive. In some cases, prior solutions for components of respiratory therapy systems may be of limited functionality, or may not be configured to take advantage of the particular configurations of the rest of the respiratory therapy system. 
     It may be desirable to further develop these devices, such as the air circuit or air tube delivery, for improvements in operations between and the interrelated components of such respiratory therapy systems. 
     SUMMARY OF THE TECHNOLOGY 
     In an aspect of the present technology, systems, apparatus and methods provide respiratory treatment for a patient. 
     Some versions of the present technology may include a breathable gas delivery conduit such as for a respiratory therapy device, such as for coupling with the device and/or a patient interface. 
     Some versions of the present technology may include such a delivery conduit with a control circuit, such as one including a wireless transceiver. 
     Some versions of the present technology may include such a delivery conduit with an integrated controller having one or more sensors to detect a condition of a breathable gas of the delivery conduit. 
     Some versions of the present technology may include such a delivery conduit with an integrated controller able to detect attachment of an accessory or patient interface to the delivery conduit. 
     Some versions of the present technology may include such a delivery conduit with an integrated controller configured to wirelessly receive identification information from an accessory or patient interface attached to the delivery conduit. 
     Some versions of the present technology may include a respiratory apparatus for coupling with a respiratory therapy device that generates a flow of breathable gas and a patient interface that delivers the flow of breathable gas to a patient. The respiratory apparatus may include a delivery conduit having a gas passage configured to conduct the generated flow of breathable gas from the respiratory therapy device to the patient interface. The delivery conduit may have a respiratory therapy device coupler end and a patient interface coupler end. The delivery conduit may have a length extending from the respiratory therapy device coupler end to the patient interface coupler end. The respiratory apparatus may include a wireless transceiver mounted on the delivery conduit at a point along the length of the delivery conduit closer to the patient interface coupler end than to the respiratory therapy device coupler end. 
     In some versions, the wireless transceiver may be configured to detect a transmitted accessory identifier from an accessory coupled at the patient interface coupler end. The wireless transceiver may be configured to read one of a radio frequency identification tag and a near field communication identification tag from an accessory coupled at the patient interface coupler end. The accessory may be a patient interface for delivering the flow of breathable gas from the delivery conduit to the patient. The wireless transceiver may be coupled to a controller, and may be configured to relay data comprising an identification of an accessory to the controller. The controller may be located at the respiratory therapy device. The controller may be located on circuit board on the delivery conduit, and wherein the wireless transceiver may be configured to relay the data comprising an identification of an accessory to the controller over a wired connection. The controller may be configured to relay the data comprising an identification of an accessory to a controller of the respiratory therapy device. The respiratory apparatus may include two or more wires extending along the length of the delivery conduit. The respiratory apparatus may include a first inductive connector adapted for connection to a power supply via the two or more wires of the delivery conduit. The respiratory apparatus may include a second inductive connector connected to circuit components of a controller to conduct power to the circuit components of the controller, the circuit components of the controller configured in a cuff adapted to couple to an end of the delivery conduit. The first inductive connector may be configured to inductively transfer power to the second inductive connector. 
     In some versions, at least one controller may be configured to determine a duration of use of an accessory attached to the patient interface coupler end. The apparatus may include the respiratory therapy device. A controller in the respiratory therapy device may be configured to operate a first switch to power a controller in the patient interface coupler end and the controller in the patient interface coupler end is configured to operate a second switch to intermittently control heating of the breathable gas flowing through the delivery conduit and data communication between the controllers. The respiratory therapy device may include a humidifier and a flow generator. 
     Some versions of the present technology may include a respiratory apparatus control device. The device may include a breathable gas delivery conduit for a respiratory therapy device. The breathable gas delivery conduit may be adapted to connect to an outlet of an airflow generator of the respiratory therapy device and may be adapted to connect to a breathable gas inlet of a patient interface. The device may include a flexible printed circuit board having a surface bent around a portion of the breathable gas delivery conduit. The device may include controller mounted to the surface of the flexible printed circuit board. The controller may be configured to control a determination of one or more parameters for the respiratory therapy device. 
     In some versions, the flexible printed circuit board may include a communications interface. The communications interface may be adapted to connect to one or more wires of a data bus along the delivery conduit. The controller may be configured to control the communications interface to transmit data signals on the data bus. The device may include a wireless transceiver mounted to the surface of the flexible printed circuit board. The wireless transceiver may be configured to communicate with one or both of: a transceiver of a controller of a respiratory therapy device; and an identification circuit of a patient interface. A parameter of the one or more parameters may be a characteristic of a breathable gas delivered through the delivery conduit from the respiratory therapy device. A parameter of the one or more parameters may be a characteristic of a patient interface coupled to an end of the delivery conduit. The controller mounted to the surface of the flexible printed circuit board may be configured to communicate a measurement of a characteristic of a breathable gas in the delivery conduit to a controller of the respiratory therapy device for close loop control of the characteristic of the breathable gas. The controller mounted to the surface of the flexible printed circuit board may be configured to determine a measurement of a characteristic of a breathable gas in the delivery conduit and to control the characteristic of the breathable gas. The controlled characteristic of the breathable gas may be temperature and the controller may be configured to operate a heater element of the delivery conduit. 
     In some versions, the controller mounted to the surface of the flexible printed circuit board may be configured to detect connection and disconnection of a patient interface to the delivery conduit and may be configure to generate a data signal to a controller of a respiratory therapy device for controlling operation of the respiratory therapy device based on the detection. The flexible printed circuit board may include one or more sensors mounted to the surface. The surface of the flexible printed circuit board may include an extension strip bent to extend through an aperture of the portion of the delivery conduit into a gas passage of the delivery conduit to extend a sensor mounted to the extension strip into the gas passage for sensing a characteristic of the gas of the gas passage of the delivery conduit. The one or more sensors may be adapted to measure at least one or more of pressure, air flow, temperature, and relative humidity of air delivered through the delivery conduit. The portion of the delivery conduit may include a cylindrical cuff of the delivery conduit adapted for removable coupling with a patient interface. The cylindrical cuff may further include a sheath to enclose the flexible printed circuit board. The cylindrical cuff may include a gas passage of the delivery conduit and the gas passage may include a heater element controlled by the controller mounted to the surface of the flexible printed circuit board. The controller mounted to the surface of the flexible printed circuit board may be configured to communicate data and to heat the delivery conduit through a set of wires by intermittently switching between heating operations and data signaling operations. The set of wires may extend along the delivery conduit and may consist of three wire conductors. 
     Some versions of the present technology may include a respiratory apparatus. The respiratory apparatus may include a respiratory therapy device to generate a flow of breathable gas. The respiratory apparatus may include a delivery conduit to conduct the generated flow of breathable gas from the respiratory therapy device to a patient interface. The respiratory apparatus may include a first controller located at the respiratory therapy device. The respiratory apparatus may include a second controller located at or adjacent to a patient-end of the delivery conduit. The respiratory apparatus may include a set of wires along the delivery conduit connecting the first controller and the second controller. The set of wires may include three wires for both heating of the delivery conduit and for data communication between the first controller and the second controller. One or both of the first controller and second controller may be configured to interleave communication operations and heating operations in alternating fashion through the set of wires. 
     In some versions, the set of wires may include a first wire, a second wire, and a ground wire. The first wire and ground wire may provide for data communication between the first controller and the second controller. The second wire and said ground wire may provide heat for the delivery conduit using power from a power supply of the respiratory therapy device. The respiratory apparatus may include a first switch located at the respiratory therapy device that may be controlled by the first controller, and a second switch located at the delivery conduit that may be controlled by the second controller. Closing each of the first switch and the second switch may control a heating operation. Closing the first switch and opening the second switch may permit control of a communication operation. The communication operation may include a transmission of a measurement from one or more sensors in the delivery conduit. In some cases, the one or more sensors may be configured to measure at least one of air flow, pressure, temperature, and relative humidity in the delivery conduit. The communication operation may include a transmission of an identification of an accessory coupled to the delivery conduit. 
     In some versions, the respiratory apparatus may include a cuff and sheath attached to the patient end of the delivery conduit. The second controller may be disposed on the cuff and covered by the sheath. 
     Some versions of the present technology may include a control method for a respiratory apparatus. The respiratory apparatus may include a respiratory therapy device to generate a flow of breathable gas, a delivery conduit to conduct the generated flow of breathable gas from the respiratory therapy device to a patient interface, and a set of wires to couple a first controller with a second controller, the set of wires extending along the delivery conduit and separating the first controller and the second controller. The control method may include receiving data through the set of wires at the first controller in a communications operation. The control method may include transmitting the data through the set of wires from the second controller in said communications operation. The control method may include heating the set of wires with one or both of the first controller and second controller in a heating operation to heat a flow of breathable gas through the delivery conduit. The control method may include interleaving the heating operation and the communications operation. 
     In some versions, the data of the communications operation indicates one or more of flow, pressure, temperature, and relative humidity of the breathable gas flowing through the delivery conduit. The heating operation may be controlled by a pulse width modulation signal. 
     Some versions of the present technology may include a method for constructing a delivery conduit assembly. The delivery conduit assembly may be for conducting a flow of breathable gas from a respiratory therapy device to a patient interface. The delivery conduit may have a cuff connector end. The method may include wrapping and affixing a flexible printed circuit board about an outer surface of the cuff connector end so as to bend a surface of the flexible printed circuit board into a cylindrical form. The cuff connector end may include a cylindrical gas passage and may have open first and second ends. The method may include attaching an end of the tube to the cuff connector end. The method may include covering the printed circuit board and at least a portion of the cuff connector end with a sheath. 
     In some versions, the method may include inserting an extension strip of the flexible printed circuit board into an aperture through the cuff connector end to insert a sensor mounted on the extension strip into the cylindrical gas passage of the cuff connector end. The method may include capping the sensor and an end of the extension strip with a cap before the inserting. The method may include affixing to terminals on the flexible printed circuit board one or more wires of a set of wires of tube. The method may include coiling a wire antenna about a channel of the cuff connector end and affixing wire ends of the wire antenna to terminals of the printed circuit board. The method may include removably coupling the cuff connector end to a patient interface. The method may include removably attaching an end of the tube to a respiratory therapy device generator using a coupler. 
     Of course, portions of the aspects may form sub-aspects of the present technology. Also, various ones of the sub-aspects and/or aspects may be combined in various manners and also constitute additional aspects or sub-aspects of the present technology. 
     Other features of the technology will be apparent from consideration of the information contained in the following detailed description, abstract, drawings and claims. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The present technology is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings, in which like reference numerals refer to similar elements including: 
         FIG. 1  is a block diagram of an example respiratory therapy system for respiratory treatment of the airway of a patient. 
         FIG. 2  is a perspective view of a form of the respiratory treatment system shown in  FIG. 1  in use by a patient. 
         FIG. 3  is a block diagram illustrating a respiratory therapy system including heating and signaling components in a delivery conduit having a heated tube, in accordance with an example of the present technology. 
         FIG. 4  is a block diagram illustrating a respiratory therapy system including heating and signaling components in a delivery conduit as a non-heated tube version, in accordance with an example of the present technology. 
         FIG. 5  is a circuit diagram illustrating a respiratory therapy system including heating and signaling components in a delivery conduit having a heated tube, in accordance with an example of the present technology. 
         FIG. 5A  is another circuit diagram of an example of the present technology with an NTC thermistor in a cuff. 
         FIG. 6  illustrates an example control scheme for the system shown in  FIG. 5 . 
         FIG. 7  is another block diagram of a system having heating and signaling components sharing a common ground wire of a delivery conduit as a heated tube version, in accordance with an example of the present technology. 
         FIG. 8  illustrates an example control scheme for the system shown in  FIG. 7 ; 
         FIG. 9  is another block diagram of a system having illustrating heating and signaling components sharing a common ground wire of a delivery conduit as a heated tube version, in accordance with an example of the present technology. 
         FIGS. 10A and 10B  are perspective illustrations showing views of an example printed circuit board for use in any of the above examples. 
         FIG. 11  is an exploded perspective view of an example assembly for a delivery conduit for a respiratory therapy system in accordance with an example of the present technology. 
         FIG. 12  is an exploded side view of an example modular assembly for a delivery conduit of a respiratory therapy system in accordance with an example of the present technology. 
         FIGS. 13A-13F  illustrate portions of the delivery conduit modular assembly of the  FIG. 12  in various stages of assembly. 
     
    
    
     DETAILED DESCRIPTION 
     Examples of the present technology may be considered in relation to the respiratory therapy system  100 , including some or all of the components illustrated in  FIG. 1 . An implementation of such components may also be considered in reference to the illustration of  FIG. 2 . For example, the respiratory therapy system  100  may include a respiratory therapy device  102  that will typically include a flow generator such as a servo-controlled blower  104 . The blower  104  will typically include an air inlet and impeller driven by a motor (not shown). Optionally, oxygen may be introduced upstream or downstream of the blower to mix with or supplement the breathable gas supplied by the impeller to the airway of a user. Moreover, an air filter  103  may be provided, such as a HEPA filter, to remove dust or other allergens from the air drawn into the air inlet. The blower may optionally be configured for generating varied flows or varied pressures associated with a patient respiratory cycle depending on the type of treatment (e.g., CPAP, bi-level, APAP etc. such as a pressure in an example range of 4 to 40 cmH 2 O, such as 4 to 15 cmH 2 O or 4 to 25 cmH 2 O) and it may further be adjusted based on respiratory conditions (e.g., apnea, hypopnea, obstruction, etc.) detected by the apparatus (e.g., apnea, hypopnea, obstruction, etc.). 
     The respiratory therapy device  102  may be configured to be connected to a breathable gas delivery conduit  106  and a patient interface  108  to deliver the flow of air or breathable gas to the upper airway(s) of a user of the device or patient. In one example, the patient interface may be a nasal mask or mouth and nose mask (example shown in  FIG. 2 ) coupled with the delivery conduit. The delivery conduit  106  may include a pneumatic coupler at each end to couple respectively with corresponding couplers of the patient interface  108  and respiratory therapy device  102  such as at an output of the blower or a volute of the blower or output of a humidifier. 
     According to one aspect, the humidifier  110  is configured to add humidity to a flow of air from the RPT device  102  as the flow of air travels therethrough. In one form, the humidifier  110  may be configured to encourage the flow of air to travel in a tortuous path through the reservoir  112  while in contact with the volume of water therein. 
     Thus, the respiratory therapy device  102  may include a humidifier  110 , which may comprise a humidifier reservoir  112  and a humidifier heater  111 . The humidifier may be configured or controlled to heat and/or humidify the breathable gas to a desired temperature and/or humidity. For example, the humidifier may be configured that the breathable gas may pass through or proximate with or to a fluid or vapor of the humidifier reservoir  112 . The heater  111  may include one or more heating elements and/or heating plates to heat the fluid contained in the humidifier reservoir  112 . In one embodiment, the heater may be based on a film laminate heater that may be fitted by adhesive to the base of a heater plate. The heater element may include a temperature sensor on the heater film. As a further option, while the heater  111  is in contact with the liquid of the reservoir of the humidifier, an additional heater that is not in contact with the liquid of the reservoir may also heat the breathable gas from the flow generator that passes through the humidifier. The humidifier may be removably coupled with the respiratory therapy device  102  as shown in  FIG. 2 , or may be integrally constructed with the respiratory therapy device  102 . 
     The respiratory treatment device may also include a controller  120  for controlling any or all of the above-described components, including the blower  104  and heater  111 . For instance, the controller, which may include one or more processors such as a programmable processor or an application specific integrated chip, may control the amount of power supplied by a power supply  114  to the controlled components. The power supply  114  may include a battery, either integrated into the respiratory therapy device  102  or housed in a separate module electrically coupled to the respiratory therapy device  102 . The power supply  114  may additionally or alternatively include or couple with an AC/DC transformer such as for receiving power from a mains power supply. In some cases, the conduit may include its own power supply such as by including a battery in the delivery conduit  106  (e.g., in its cuff). 
     The respiratory therapy system  100  may comprise one or more sensors. The controller  120  may be coupled to, or receive signals from, the one or more sensors, such as a flow (also referred to as a flow rate) sensor, temperature sensor, pressure sensor, relative humidity sensor, etc., to receive sensor data, and to determine control operations of the respiratory therapy device  102  based on the received sensor data. In some examples, one or more sensors may be configured to sense conditions in relation to one or more of the blower  104  and the humidifier  110  so as to provide data and/or signals concerning such conditions. For example, a flow sensor  132  may be positioned at or near an inlet of the blower, within the blower, outlet of the blower  104  or volute of the blower, and temperature and humidity sensors  134 ,  136  may be positioned at or near the humidifier reservoir  112 . The temperature and humidity sensors generate temperature or humidity signals for controlling or setting temperature and/or humidity of the device. 
     Some sensors may be located for measuring ambient conditions. Alternatively or additionally, one or more sensors, such as sensors  142 ,  144 ,  145  may be positioned downstream in the delivery conduit  106 , for instance, at or near the patient interface  108 . Such sensors of the delivery conduit may be, for example, one or more of pressure, humidity, temperature, and flow sensors. For example, such sensors may be pressure, humidity and temperature sensors. 
     Additional components for the respiratory therapy system  100  may also be included at or integrated within the delivery conduit  106  to complement and/or function with the components of the respiratory therapy device  102  or other parts of the system. These additional components may improve the communication of information among the respiratory therapy device  102 , such as with its controller, the humidifier  110 , the delivery conduit  106 , and the patient interface  108 . The additional devices may also provide additional (or improved) functionality to the respiratory therapy system  100 . For example, different sets of components (e.g., sensors) may be included in different versions of the delivery conduit. These sets of components of the delivery conduit may then be utilized by the controller of the respiratory therapy device  102  when the different/new delivery conduit version is connected to the respiratory therapy device  102 . For example, the controller may detect coupling of a new delivery conduit and change operations, such as treatment operations, depending on the capabilities of the accessory components of the newly coupled delivery conduit. In this regard, the delivery conduit may be configured with components to permit electronic communications (e.g., wired or wireless) between the delivery conduit and the respiratory therapy device  102  (e.g., controller  120 ). Utilization of delivery conduits having control circuits and sensors can permit ready replacement and upgrading of components for the maintaining or upgrading operation of respiratory therapy device to which they may be used. 
     For example, a wireless transceiver  152 , such as a radio frequency identification (RFID) reader or near field communication (NFC) reader, may be provided in or on the delivery conduit to assist in relaying information between components of the respiratory therapy device  102 . The transceiver may, for example, be provided close to a patient-end or proximal the end of the delivery conduit (e.g., closer to the end of the delivery conduit connected to the patient interface  108  than to the end connected to the blower  104 ), and configured to read data stored on a transmitter  160  or other identification circuit, such as an RFID tag or NFC tag, of a device coupled to the delivery conduit. For example, when a patient interface  108  with such a transmitter or tag is activated, or coupled to the delivery conduit, it may transmit its data to the transceiver of the delivery conduit. Such transmittable data may indicate one or more of the type, model number, production date, or any other relevant information about the connected device or patient interface  108 , information in relation to use of the connected device, and information in relation to the user. In some cases, the wireless transceiver may be, alternatively or additionally, implemented for such transmissions using other wireless protocols, such as, for example, Bluetooth or Bluetooth LE. 
     The wireless transceiver  152  may also communicate information to a control processor, such as controller  120  of the respiratory therapy device  102 , or to a secondary controller  156  (e.g., microprocessor or microcontroller) located towards or at a proximal (patient end) of the respiratory therapy system, for example integrated with the delivery conduit  106  (discussed in more detail below). The information communicated by the transceiver may include, for example, sensor data (e.g., from sensors  142 ,  144  or  145 ), sensor configuration/type, and/or tag data (e.g., from tag or transmitter  160 ). In some cases, the secondary controller  156  may relay data obtained from the transceiver by sending the data to the controller  120  of the respiratory therapy device  102 . The controller  120  may then utilize the relayed information to customize control operations, such as to meet specific preferences or requirements of the patient interface  108  or therapy control. Alternatively or additionally, the controller  120  may use the relayed information to determine how long the patient interface has been in use (e.g., based on a first time the patient interface was detected by the transceiver, based on a total duration of time for which the patient interface has been detected by the transceiver), and may control operations, such as generating time of use related warnings, accordingly. The transceiver may similarly be capable of reading and relaying data stored on other accessories connected to the respiratory therapy device in order to further customize operation of the device. 
     In some versions, the delivery conduit control circuit may include a sensor configured to determine a presence (or absence) of an attachable accessory/component. For example, an inductive proximity sensor may be located in a cuff. In some such versions, the sensor may determine a presence of the accessory (e.g., a patient interface) such as with a metal (ferromagnetic) ring. 
     Information from the delivery conduit sensors (e.g., sensors  142 ,  144 ,  145 ) and/or transceiver  152  may be relayed to the controller  120  by either wired or wireless signaling or communication. For example, wired communications may be implemented via a wired data bus  170  of a set of wires extending along the delivery conduit including two or more wires extending the length of the delivery conduit from the respiratory therapy device  102  to the transceiver. Wireless communications may be implemented with the transceiver  152  and an optional second transceiver  122  integrated with or coupled to the controller  120  within the respiratory therapy device  102 . Wireless communications from the transceiver  152  may be implemented via a direct wireless connection between the respiratory therapy device transceiver and the conduit transceiver, or via any number of intermediate communications links, such as via a remote control, a smartphone, an internet such the Internet, etc. Such communications can provide the controller  120  with information to, for example, adjust parameters and settings of a therapy provided with the controller  120 . For example, such information from sensors can serve as input to any control loop implemented by the controller  120  with the respiratory therapy device (e.g., pressure control, temperature control, flow control, humidity control, etc.). 
     In some cases, the delivery conduit may also include one or more heater or heating element(s), such as a delivery tube heater  154 . These components may be provided in or on the delivery conduit  106 , such as substantially along its gas path, to assist with maintaining the temperature of the breathable gas after it passes from the humidifier or flow generator into the delivery conduit. In some versions, one or more heater or heating element(s) may be isolated at an end portion, such as within a cuff, of the delivery conduit. Thus, the delivery conduit may have one or more heating elements along the gas path and/or within a cuff of the delivery conduit. By keeping the delivery conduit warm, condensation in the delivery tube may be reduced or avoided as the breathable gas traverses the delivery tube toward the patient. The secondary controller  156  may be operatively coupled to the sensors in the delivery conduit, and may be responsible for processing information received from the sensors. The secondary controller  156  may further be operatively coupled to accessory devices in the delivery conduit, such as its heating elements or the delivery tube heater  154 , in order to regulate the temperature of the breathable gas in the delivery conduit. 
     In some versions, the secondary controller  156  may receive a measurement signal from a humidity sensor  145  indicating an amount of moisture buildup in the delivery conduit. Based on the received measurement, the secondary controller  156  may communicate the received information to the controller  120  located at the blower so as to provide information for controlling heating of the breathable gas flowing through the delivery conduit. Similar functions may be performed for other parameters of the breathable air passing through the delivery conduit, such as temperature, pressure and/or flow from other sensors of the delivery conduit. In some versions, the secondary controller  156  may receive the sensed measurement(s), and may itself control heating of the breathable gas in response to the measurement such as by selectively activating/operating the heating elements of the delivery conduit. In some such versions, any of the controllers may be operatively coupled to a switch to control opening (i.e., breaking) or closing (i.e., completing) a heating circuit for the heating elements of the delivery conduit. 
     The secondary controller  156  of the delivery conduit may also receive information (e.g., from the wireless transceiver) indicating whether a patient interface is or is not connected to the delivery conduit so as to detect the connection of the patient interface. Such information may serve as a control signal such as for permitting or prohibiting activation of one or more components of the delivery conduit and/or respiratory therapy device  102 . For example, if no patient interface is detected, the secondary controller  156  may communicate an indication of the absence of a patient interface to the controller  120  of the respiratory therapy device  102 . Either controller may control the heating elements, such as via the aforementioned switch, to prevent heating, such as of the delivery conduit, while the patient interface is disconnected such as in the sense of an override. Similarly, information concerning detection of the connected patient interface may serve as a control signal, which may be communicated to the controller  120 , to permit activation of the heating element(s), such as the elements of the delivery conduit. 
     In some versions, the heater  154  may be implemented with a first subset of wires, such as two or more wires, of a set of wires extending along or embedded in the delivery conduit. The wires may be heating elements designed to warm and transfer heat to the passing breathable gas by an application of electrical current to the wires. The heater  154  may be included in one or more of: the tubing of the delivery conduit, or a cuff attached to an end of the delivery conduit at which the conduit connects to the patient interface. The cuff may serve as a coupler for removeably connecting the delivery conduit to a corresponding coupler of the patient interface for use. 
     Examples of the delivery conduit for some versions of respiratory therapy system may be considered in relation to the block diagrams of  FIGS. 3 and 4 . For example, in the diagram of  FIG. 3 , the respiratory therapy system  300  of  FIG. 3  illustrates a gas path of a conduit portion  301 , such as a tube or tubing, of the delivery conduit (from the blower end  312  (distal end) to the patient end  314  (proximal end)). A cuff  308  including a delivery conduit control circuit  303  is at the patient end. The gas path of the conduit portion  301  is warmed by heating wires  302 ,  304 , that may be provided in the conduit portion  301 . The heating wires  302 ,  304  may be spiraled around and along the gas path, such as in, on or around the tube. The heating wires  302  and  304  may be insulated electrically and/or thermally, such as by methods and arrangements known in the art. 
     One of the heating wires  302  receives power from a power supply at the blower end  312  of the conduit portion  301 , while the other wire  304  may be coupled to ground at the blower end  312  of the conduit portion  301 , thereby completing a heating circuit. In the example of  FIG. 3 , the wires  302 ,  304  may also be configured to deliver power from a power supply, such as of the respiratory treatment device, to one or more the components of the delivery conduit control circuit  303  at the patient end  314  of the conduit portion  301 . For example, at some point, such as a mid-point, in the heating circuit (e.g., at the patient end  314  of the conduit portion  301 ), the wires  302 ,  304  may be connected to a converter  325 , such as a DC-DC converter, that converts the incoming power signal to a level suitable for operating the secondary controller  356  of the delivery conduit control circuit  303 . Such a converter may also convert the supplied power for powering the delivery conduit sensors  344 ,  346  and transceiver  352 . In some versions, the converter may convert a supplied 12 volt power signal into a 3 volt power signal. Other power signals/conversions may also be implemented. An optional switch  332  may be implemented with the heating circuit for selective control of the supply of power through the heating circuit as previously discussed and discussed in more detail in relation to  FIG. 5 . 
     The conduit portion  301  of the respiratory therapy system  300  may also include data bus having two or more additional data bus wires  371 ,  372  for relaying signals between components at the blower end  312  (e.g., integrated sensors, transceiver, secondary controller) and components at the patient end  314  (e.g., transceiver  352 , secondary controller  356 ). In the example of  FIG. 3 , wire  371  carries signals to or from a communications interface  380 , such as a serial RS232 interface or driver, (which may optionally also be powered by the heating wires—not shown in  FIG. 3 ) interfacing the secondary controller  356  with the controller  120 . Wire  372  serves as a ground wire, thereby completing a signaling circuit for the communications with the interface  380 . 
     The example of  FIG. 4 , the delivery conduit circuit components are similar to that of the version of  FIG. 3 . However, in  FIG. 4 , a heating element  407  is added at the cuff  408  of the delivery conduit at the delivery conduit control circuit  403 . Thus, the example respiratory therapy system  400  of  FIG. 4 , the breathable gas that passes through the cuff may be warmed by a heating element  407  (e.g., inductive heater, or other heat dissipater) located within a heated cuff  408  at a patient end of conduit. The conduit portion  401  still includes wires  402 ,  404 , which supply power from a power supply at the blower end  412  to the heating element(s)  407 , but may or may not themselves dissipate power along the length of the conduit portion  401  depending on whether the conduit portion includes heating elements or not. 
     As with the design of the respiratory therapy system  300  of  FIG. 3 , wires  402  may supply power to other components included in the heated cuff  408 , such as components of the delivery conduit control circuit  403  (e.g., transceiver  352 , secondary controller  356 , converter  325 , sensors  344 ,  346 , and/or communications interface  380 ). Also, as with the design of the respiratory therapy system  300  of  FIG. 3 , conduit portion  401  may also include data bus wires  471  and  472  for communicating signals between components on both ends of the delivery conduit, such as controller  120  and secondary controller  356 . 
     Although wired power connections are illustrated in  FIGS. 3 and 4 , in some versions, power of the delivery conduit control circuit(s) may be implemented with contactless power transmission. For example, the delivery conduit assembly may include an inductive connector such as at a patient end and/or a flow generator end. In one arrangement, the tubing assembly may comprise a two wire heating circuit. The circuit may include an end coupler portion, at an end of the delivery conduit, having a wireless power connector. The wireless power connector may then be connected to an accessory, such as a cuff having a delivery conduit control circuit as describe in more detail herein, where the accessory includes a (complementary) connector portion to receive wireless power from the wireless power connector of the delivery conduit. Thus, the accessory or cuff may receive wireless power to power its operations (e.g., sensing, accessory attachment detection and/or identification, wireless communication (e.g. Bluetooth) for communication (e.g., with the respiratory therapy device) of data, such as from its sensors or component detectors, etc. 
     As previously discussed, such as in relation to the wiring of  FIGS. 3 and 4 , heating and signaling may be controlled by a controller  120  connected near the blower end of the delivery conduit. In this regard,  FIG. 5  further illustrates an example control application for the system  300  of  FIG. 3 , which can be similarly applicable to the system  400  of  FIG. 4 . In the diagram of  FIG. 5 , the blower end  512  of the conduit may be coupled to a respiratory therapy device  102  that includes a switch  532  for controlling heating operations through the conduit portion  501 . A controller  520  (such as a microcontroller or microprocessor unit) is operatively coupled to the switch  532  and may be implemented to control the timing of the heating operations. 
     In the example of  FIG. 5 , an optional load capacitor  540  is coupled to the heating wires  502 ,  504  in order to maintain charge even when the switch  532  is open. Charging of the capacitor may be implemented from the wire  502  through a diode  543 , which can be arranged to permit current flow from the wire  502  only in the forward direction of the converter and capacitor. Thus, when the switch  532  is open, the load capacitor  540  may continue to provide energy (e.g. a charge) to the DC-DC converter  525 , and not the reverse direction to the wires  502 ,  504 , in order to continuously power the patient-end components (e.g., temperature sensor  544 , humidity sensor  546 , and RFID reader  552 ). In the version illustrated, an optional switch  541  in the control circuit of the respiratory therapy device  102 , under control of the controller  520 , may be selectively controlled so as to either (a) receive communications through a communications interface at the controller  520  or (b) to receive a sensor signal at controller  520 , both via the wire  572 . In this regard, an analog sensor signal proportional to a sensor (e.g., any of the provided sensors such as a temperature and/or humidity sensor) reading/measurement may be provided on the wire  572  from the cuff circuitry for sampling by the controller  520  at an analog-to-digital (ADC) input sampler(s). Alternatively, a data signal may be provided from the cuff circuitry on the wire  572  for receiving by a signaling interface of the controller  520  (e.g., via an RS232 driver and universal asynchronous receiver/transmitter input of the controller  520 .) According to one aspect, the switching  532  may allow different types of cuff configurations to be connected, such as those shown in  FIG. 5  and  FIG. 5A .  FIG. 5A  shows another example arrangement of the present technology comprising an NTC thermistor  590  in the cuff. 
     Operations of the circuits of  FIG. 5  may be considered in reference to the signaling graphs of  FIG. 6 , which illustrate an example scheme for intermittent control of the heating and signaling operations that may be implemented by the controller  520 , such as by selective operation of switch  532 . For clarity, the vertical axis represents amplitude, and the horizontal axis represents time. Curve  610  shows voltage verses time along heating wire  502 . In effect, this demonstrates operation of the switch  532 , in which power is cyclically provided to and cut off from the heating wires  502 ,  504 . Operation of the first switch may be a pulse width modulation, in which the controller  520  controls the duty cycle of the switch. Curve  620  shows the voltage verses time provided to the converter  525 , which in part is supplied by the load capacitor  540  during the tube off cycle. In this regard, charge from the load capacitor  540  is maintained at a relatively constant level, allowing for the converter  525  to maintain a sufficient constant output voltage (shown at curve  630 ) for continued operation of the patient-end components (e.g., second controller  554  etc.). 
     Curve  640  of  FIG. 6  shows an example voltage verses time plot of signaling wire  572  which provides data transfer between the controller  520  and second controller  554 . In the example of  FIG. 6 , data may be continuously transmitted from the patient-end secondary controller  554  to the blower-end controller  520 . Thus, the wire  572  in this version may be implemented solely for data communications. However, in other examples discussed herein, additional switches may be provided to control when signaling operations occur. 
     One example in which it may be advantageous to control the timing of signaling operations is shown in  FIG. 7 . In this version, the heating and signaling operations may time share a common wire, such as a ground or return wire. Thus, in some versions fewer wires may be implemented. In the example of  FIG. 7  three wires may be implemented for both the signaling and heating operations of the conduit such that one of the wires may be intermittently engaged for completing the signaling and heating alternatively. In  FIG. 7 , an example respiratory therapy system  700  includes a respiratory treatment device  702  (e.g., such as a flow generator with or without a humidifier) for providing breathable gas to a patient (not shown) through a delivery conduit  706 . The breathable gas is warmed in the delivery conduit by a heating element of wire  707 , such as those described above. The patient-end  714  of the delivery conduit  706  also includes a secondary controller  754  that communicates with a controller  720 , such as through a switch or multiplexer  721 , at the blower-end  712  of the delivery conduit  706  over a data bus wire  708 . A common ground wire  709  is provided in the delivery conduit  706  to alternatingly complete the heating circuit of the heating wire  707  and the signaling circuit of the data bus wire  708 . In this manner, only one of a heating operation and a signaling operation may be performed at a given time. 
     In order to control the heating and signaling operations in this version, each of a first switch  732  and a second switch  739  are provided in the respiratory therapy system  700 . The first switch  732  is located in the respiratory therapy device  702  at the blower-end  712  of the delivery conduit, and its activation is selectively controlled by the controller  720 . The first switch  732  is similar in operation to that of switch  532  of  FIG. 5 . It operatively couples and decouples wire  707  to a high or positive side of a power supply (e.g., 24 volts). The second switch  739  is located in the delivery conduit such as in the delivery conduit control circuitry  703  of the cuff of the delivery conduit. The activation of the second switch  739  is selectively controlled by the second controller  754 . The second switch  739  is operatively controlled to couple and decouple the proximal end of wire  707  to ground wire  709 . When so coupled, a heating operation can occur due to completion of the heating circuit when wire  707  is powered. At this time, power to the converter  725  is shorted, thereby temporarily denying power supply to the converter. When the proximal end of wire  707  and the ground wire  709  are decoupled by the second switch  739 , the heating circuit is broken and in this condition the converter can be powered by the power supply when wire  707  is powered. During this latter condition, the signaling circuit of wires  708 ,  709  may be completed for signaling by the signaling operations of the microcontroller  720 . 
     Thus, one or both of the controller  720 ,  754  may be configured to interleave the heating and signaling operations, such as in alternating fashion, such that these operations alternate so as to avoid a simultaneous heating control operation and a data communication control operation. An example signaling control scheme  800  for such interleaving employing the components of  FIG. 7  is illustrated in  FIG. 8 , in which operation of the first switch S 1  (e.g., first switch  732  of  FIG. 7 ) and operation of the second switch S 2  (e.g., second switch  739  of  FIG. 7 ) are shown. 
     The interleaved operations may be cyclical but may be considered to begin with a blanking window  802 . During a blanking window, the controller  720  controls operation of the first switch to close to allow supply of power to the heating wire  707 . During this blanking window  802 , the secondary controller controls operation of the second switch to open (so as not to complete the heating circuit). During such a blanking window, power supplied over heating wire  707  is applied to the converter  725 , thereby powering the patient-end sensors and secondary controller  754 . Moreover, during such a blanking window, the wire  709  is available to complete the signaling circuit, which in turn allows for signaling to occur between the patient-end and blower-end sensors and controllers. The blanking window thus permits signaling and may last a predetermined amount of time and may be periodically repeated. 
     After the blanking window, a heating window  804  may begin. During the heating window, the controller  720  continues to control the first switch to apply power to the wire  707 . During the heating window, the secondary controller  754  also controls the second switch  739  to activate the heating operation by closing so as to couple wire  708  and wire  709  at the second switch  739 . In this regard, the secondary controller  754  can control the desired time period for heating by controlling the second switch. For example, when the second switch is closed/on (heating operations occur) and when the second switch is open/off (heating operations suspend). The longer the second switch is maintained in the closed position, the longer the heating circuit is completed and the more heat is transferred to the breathable gas of the delivery conduit. In other words, when both switch S 1  and switch S 2  are on, heating operations occur. When switch S 1  is on and switch S 2  is off, information signaling can occur. The controllers may operate these switches by various signaling schemes, such with pulse width modulation, for permitting the interleaved heating and signaling operations. 
     For example, the controller  720  may generate pulse width modulation signals to control of the first switch to activate the heating and signaling cycles. In some cases, the second controller  754  may generate pulse width modulation signals to control of the second switch to interleave heating and signaling cycles. Such signals may be continuously repeated. Thus, the interleaving operations may be performed by the second controller at a predetermined and fixed frequency. However in some cases, the interleaving may be more dynamically implemented, such as in relation to a condition detected by the second controller  754 , such as in relation to measurements made by one or more of the sensors of the delivery conduit control circuit and/or a determination made with its transceiver. 
     A level detector  772  is used to obtain the status of switch S 1  in respiratory treatment device  702 . In the example arrangement shown in  FIG. 7 , the level detector allows synchronization of S 2  with S 1 . Note also that DC to DC converter  725  may be understood as an implementation in which the diode  543  and capacitor  540  shown in  FIG. 6  are included in converter  725 . 
     Another example respiratory therapy system  900  may be considered in relation to  FIG. 9 . This example includes components similar to those of the version of  FIG. 7 . In this example, the delivery conduit portion  901  may optionally omit a heating element. Moreover, in this version a heating element may be located with the delivery conduit control circuit  903  located within the heated cuff  905  at a patient end of a delivery conduit  906 . Thus, the breathable gas traversing through the delivery conduit can be warmed by a heating element  911  (e.g., heat dissipater) located within a heated cuff  905  at a patient end of a delivery conduit  906 . Similar to  FIG. 7 , the system includes a controller  920  in a respiratory treatment device  902  and a secondary controller  954  included in the cuff  905 . These devices may control operations so as to interleave heating and signaling operations in relation to the heating wire  907 , and signaling wire  908 , and a common wire  909  (ground) through the conduit portion  901 . The same or similar interleaving scheme discussed in connection with  FIGS. 7 and 8  may be utilized in the system  900  of  FIG. 9 . 
     The above example systems include several patient-end components (e.g., delivery conduit control circuit) of a delivery conduit  106  that may be formed of discrete circuit element. However, in some versions thereof, the circuit elements may be integrated in a single module, such as a printed circuit board. An example of such an integrated circuit board may be considered in relation to the illustration of  FIG. 10 . In this regard,  FIGS. 10A and 10B  show opposing surface side of an example circuit board  1000  that may be adapted to be flexible so that it may conform to a shape of an exterior of a delivery conduit comprising an air path therethrough. For example, the circuit board  1000  may be configured to bend or curve around a substantially cylindrical (e.g., mostly cylinder shaped, mostly oval shaped etc.) delivery conduit. Thus, such a circuit board may be made of a flexible material. Its length may be configured so that the board can be wrapped or bent around all or most of the perimeter or circumference of a delivery conduit. In some instances, the circuit layout of the board and its materials may be arranged to permit bending along a lengthwise axis L, but to remain rigid along a widthwise axis W. Such a design can permit its insertion within a smaller housing while still protecting the electrical elements of the board. 
     The circuit board may include components of any one or more of the delivery conduit control circuits previously described. For example, it may include one or more of: a microcontroller or microprocessor unit, one or more sensors (e.g., for detecting/measuring a property of the breathable gas passing through the delivery conduit, such as its temperature or humidity), and a wireless transceiver (e.g., for communicating with a controller of a flow or pressure generator, for communicating with an identification tag located in a patient interface). These components may be mounted to the circuit board. 
     The circuit board may include a main body portion  1001  with a first surface MS on which all or some of the above-described components are integrated. Extending in the lengthwise direction L from both ends of the main body portion may be a pair of mounting tabs  1005  and  1006 . Each mounting tab may extend most of the widthwise direction L of the main body portion. The circuit board may include an extension strip  1009  on which at least one of the sensors may be mounted. The extension strip  1009  may extend in the lengthwise direction L, and may extend further than even the adjacent mounting tab. The extension strip  1009  may be adapted to extend into an air path defined by the delivery conduit through which breathable gas flows. Thus, the sensor(s)  1016  mounted on the extension strip may be exposed to, or located close to (e.g. separated only by a protective housing) the flow of the breathable gas and to sense a characteristic thereof, such as temperature or relative humidity, from within the gas passage of the delivery conduit. The extension strip  1009  may be located at an end of the circuit board, and may be laterally adjacent to a mounting tab. 
     The circuit board may also include terminals  1020  to which the heating, signaling, and ground wires extending along the delivery conduit may be coupled or attached (e.g., soldered). In one example, the terminals may connect to a data bus port for communication information between the integrated components of the circuit board and the controller  120  of the respiratory therapy device  102 . The terminals may additionally connect to a power line for receiving power to charge the components of the circuit board. The circuit board may also include terminals  1023  for attachment to an antenna, such as an RFID antenna. The terminals  1023  may be configured to connect to a transceiver, such as an RFID or NFC transceiver (such as the transceiver  152  described in relation to  FIG. 1 ). For example, an RFID coil may be attached to the terminals  1023 . 
     The circuit board may also include holes or grooves to facilitate fixing or securing the board to the delivery conduit housing when wrapped about to a portion of the delivery conduit. For example, such hole may couple to a post structure of a cuff housing of the delivery conduit. In the example of  FIGS. 10A and 10B , each of the tabs  1005  and  1006  includes a respective hole  1011 ,  1012 . The main body portion of the circuit may include additional holes  1013 ,  1014 , which may be aligned, lengthwise, with holes  1011  and  1012 . 
     In the example of  FIGS. 10A and 10B , the outline of the main body portion of the circuit board is substantially rectangular in shape. However, in other examples the surface of the main body portion may have a different shape. For instance, a middle portion of the surface of the main body portion may be tapered to have a narrower width than the remainder/ends of the surface of main body portion. Thus, the surface of the circuit board may be an hourglass shape. 
       FIG. 11  illustrates a portion of an example of such a flexible circuit board of an hourglass shape in relation to an exploded view of the components of a delivery conduit assembly. The flexible circuit board  1105  also includes an extension strip  1109  comprising a sensor, such as a relative humidity and temperature (RHT) sensor  1111  and configured to be bent to place in the path of the breathable gas. For example, the extension strip  1109  may be configured to bend approximately ninety degrees for insertion into the air passage of the cuff. In the example, a delivery conduit assembly  1100  includes the circuit board  1105 , which may be wrapped around the delivery conduit at or near a patient-end of the delivery conduit. In the example of  FIG. 11 , the delivery conduit assembly  1100  includes a hollow cylindrical cuff  1140  that may serve as a dongle. The cuff  1140  may have one or more structural mounting features (e.g., tabs, projections, slots, etc.), such as aperture  1142  to receive there through the extension strip  1109  of the circuit board, on an outer surface thereof. The mounting features of the cuff may be adapted to align with and to the complementary mounting features of the circuit board, for example to extend through the respective holes positioned on the circuit board, such that the circuit board may be affixed to the cuff. The cuff  1140  may be integrally connected to a tube portion  1106  of the delivery conduit, such as by overmoulding, or be configured to be removably coupled to the tube portion  1106 . In one example, the cuff  1140  may comprise features in its inner surface (e.g., shaped and sized complementarily to the tube portion) adapted to receive the tube portion  1106 . 
     The example of  FIG. 11  shows a cuff comprising (e.g., adapted to enclose) a heating element or evaporator  1160 , particularly an evaporator, such as when the cuff serves as a heated cuff of the delivery conduit. The evaporator  1160  (shown as heating element  911  in  FIG. 9 ) has a diameter roughly equal to the inner diameter of the cuff, such that any breathable gas that flows through the cuff from the central flexible hose portion of the delivery conduit  1106  to the patient interface may be heated by the evaporator. In one example, a humidification system such as one described in the PCT Patent Application PCT/AU2017/050912, the entire disclosures of which is incorporated herein by reference, may be suitable for use with the evaporator  1160  shown in  FIG. 11 . 
     In one example, the printed circuit board  1105  may include a set of terminations  1122  for connecting to the wires  1004  of the delivery conduit (e.g., wires  707 ,  708 ,  709  of  FIG. 7 ), and a set of terminations  1124  for connecting to the leads (e.g., high side and low side) of the evaporator to power the evaporator. Another set of terminations  1126  are provided for connection to an RFID coil. As illustrated in  FIG. 11 , the heating/signaling/ground wires of the set of wires of the delivery conduit are wrapped or molded to an outer perimeter of the tube portion, such as in its helical rib. In the example of  FIG. 11 , the outside diameter of the cuff is in a range of approximately 25 to 35 millimeters such as about 30 millimeters. In some versions, the cuff may have an outer diameter in a range of about 22 mm to about 25 mm. In other versions, such as for example a Dongle design, an outside diameter of 30 mm may prove suitable. In addition, for a Dongle design an extended flexible bridge portion  1130  may be implemented to allow for different Dongle diameters. 
     As such, the cuff may then serve as a coupler for removable connection of the delivery conduit to a patient interface. In some versions, the inner surface of the cuff may define a tubular space through which air flows from the delivery conduit to the patient interface. The outer surface may also be substantially concentric to the inner surface. The cuff may further comprise a hollow space therebetween, and the printed circuit board (and components mounted thereon) may be disposed in the hollow space. For example, the cuff may comprise an outer casing or sheath portion, for example molded to form a protective layer (e.g. to form a water ingress seal) over the cuff mounted circuit board so as to protect the circuit board (e.g. from human contact or accidental damage) during use. In some such versions, the sheath or outer casing may be a TPE or silicone overmould. The sheath can protect the electrical components of the cuff but may also serve to seal the cuff from the potential for any air/gas leaks from inside the cuff such as when the cuff includes apertures, slots or other channels to permit wiring or mounting of the circuit board. The outer sheath portion may also provide a convenient, high-friction gripping surface for a user. 
     In some versions, the cuff may be configured with additional components, for example, the cuff may include a heat and/or moisture exchanger and/or vent. For example, any of the exchangers described in U.S. Patent Application Publication No. US-2014-0305431, the entire disclosure of which is incorporated herein by reference, may be included in the cuff. By way of further example, any of the vents described in U.S. Patent Application Publication Nos. US 2014/0283831 and US 2014/0069428, the entire disclosures of which are incorporated herein by reference, may be included in the cuff. 
     Another version of an example delivery conduit  106  is illustrated in  FIG. 12 . The figure shows a portion of the conduit in an exploded view with several components. In this version, the delivery conduit includes a hollow tube portion  1206  having one or more wires  1204 (e.g., wires  707 ,  708 ,  709  of  FIG. 7  or wires  302 ,  304 ,  371 ,  372  of  FIG. 3 ) helically or spirally wrapped around its outer circumference. Such a configuration of wires in relation to the delivery conduit may be considered a rib. The assembly also includes a delivery conduit connector end  1210  (or end portion of a cuff) adapted to be fixed to an end of the hollow tube. The assembly also includes a printed circuit board  1205  such as any of the delivery conduit control circuits previously described. In this version it is adapted to be flexibly wrapped around an outer surface of and affixed to the delivery conduit connector end  1210 . In this version, the assembly also includes a sensor case  1230 . The sensor case covers a sensor for protection. In this regard, the sensor case may cover a sensor of the printed circuit board that extends through an opening in the delivery conduit connector within the gas passage/path of the delivery conduit connector. Such a sensor may be a sensor on the extension strip  1009  shown in  FIG. 10A . Thus, the sensor case  1230  may be within the gas passage of the cuff. The assembly of  FIG. 12  also includes a sheath or outer casing  1240 , such as an over-mold, for encasing all or part of the above-mentioned assembly components associated with the cuff. In some forms, the outer casing  1240  may comprise multiple molded components which are assembled together to encase all or part of the above-mentioned assembly components associated with the cuff. Advantageously, use of a flexible circuit board may simplify the manufacturing process, and reduce a size of the delivery conduit  1206 , by allowing the electronic components to be compactly packaged around a periphery of the delivery conduit  1206 , while an operator (or an automated process) may simply wrap the flexible circuit board. 
     Assembly of the delivery conduit of  FIG. 12  may be considered in relation to  FIGS. 13A-13F . These figures illustrate one example of features and steps for bringing together the components. While the steps are shown in a particular order for discussion purposes, it will be understood that some steps may be may be omitted, additional steps may be added, and certain steps may be performed either simultaneously or in a different order. 
     In  FIG. 13A , the hollow tube portion  1206  is inserted into the delivery conduit connector end  1210 . The hollow tube is configured so that the rib  1207  comprising wires  1204  can be inserted into slots  1301  of the delivery conduit connector end. For example, each slot may hold one wire. For example, four slots may be included in the connector end or cuff. Such alignment slots position the wires to permit ready connection of the ends of the wires with the terminals of the circuit board when the board is added. 
     In  FIG. 13B , the printed circuit board  1205  is wrapped around the outer circumference of the delivery conduit connector end  1210 . The wires  1204  may be soldered/welded to the appropriate terminals of the circuit board (e.g., terminals  1122  of  FIG. 11 or 1020  of  FIG. 10A ). Also, an antenna (not shown), such as an RFID coil, may be connected/welded/soldered to a transceiver module of the circuit board. The antenna may be wound around the outer perimeter of the delivery conduit connector end in an antenna slot  1305  between the delivery conduit connector end  1210  and the printed circuit board. 
       FIG. 13C  shows the printed circuit board and delivery conduit connector end from an opposing side view relative to  FIG. 13A . In  FIG. 13C , slots  1011  and  1012  of the printed circuit board (see also  FIG. 13D ) are shown to clip together with projections  1321  and  1322  of the delivery conduit connector end  1210 . Thus, the board may be wrapped or rolled around the delivery conduit connector end to engage the slots and projections for securing the board to the cuff. In some versions, when included, the extension strip  1009  of the circuit board (shown in  FIG. 13B ) may first be inserted in a sensor aperture of the delivery conduit connector end before flexibly wrapping the board around the cuff/delivery conduit connector end. Such a wrapping bends the extension strip. The sensor aperture permits the extension strip  1009  and its sensor to extend through the connector end and into the gas passage of the delivery conduit connector end. 
     Such an insertion of the flexible extension strip sensor may be considered in relation to  FIGS. 13D and 13E .  FIG. 13D  shows the sensor case  1230  inserted over a sensor(s) of the extension strip  1009  of the circuit board  1205  so as to cover one or more sensor(s) of the printed circuit board. The sensor(s) and case may then be inserted through the sensor aperture in the delivery conduit connector end so that they are positioned within the conduit and so that the sensor is capable of measuring one or more characteristics of the breathable gas, such as its temperature or humidity, etc. In  FIG. 13E , the covered sensor and its case  1230  can be seen protruding through a sensor aperture  1350  in the delivery conduit connector end  1210 . As illustrated, the sensor case  1230  includes a base portion  1331  that corresponds to the sensor aperture and the contour of the inside gas passage surface of the connector end so as to smoothly seal the sensor aperture with the contour of the surface of the gas passage when inserted into the aperture. The base also permits proper orientation of the sensor case within the connector end. In this regard, the sensor case also extends the sensor into the gas passage at a sensor end  1333  of the sensor case. In this version, the sensor end  1333  of the sensor case has an aerodynamic profile to minimize gas flow resistance with the flow of air though the gas passage of the delivery conduit connector end as it travels around the sensor end. For example, the sensor end  1333  of the case may have an oval profile as seen in a cross sectional plan view  1335  (also shown in  FIG. 13E ) of the cuff and the sensor case within the airflow path/passage of cuff. 
       FIG. 13F  illustrates the application of the outer casing  1240 . Such a casing or sheath component may be slideably engaged over the hollow tubing portion  1206  until coming into contact with the seat end  1337  of delivery conduit connector end  1210 . The casing  1240  may then be affixed to the delivery conduit connector end  1210 , for instance using an ultra-sonic welder or other affixing method. Thus, the casing may seal therein the electrical components of the delivery conduit connector end and seal the delivery conduit end against air leaks from the passage within the cuff. 
     In one example, the delivery conduit shown in  FIG. 13F  may comprise a wireless transceiver as described elsewhere in the present specification, and configured to communicate with a patient interface. The wireless transceiver may be an NFC reader, and may be configured to communicate with an NFC tag located on the patient interface, such as when the patient interface is connected to the delivery conduit or is put in proximity thereto. The patient interface may comprise a connector configured to be inserted into the cuff of the delivery conduit, wherein the connector comprises the NFC tag. The delivery conduit may in use generate a signal indicating some or all of the information obtained from the NFC tag, such as a type or age of the patient interface, to the controller  120 . 
     In the foregoing description and in the accompanying drawings, specific terminology, equations and drawing symbols are set forth to provide a thorough understanding of the present technology. In some instances, the terminology and symbols may imply specific details that are not required to practice the technology. Moreover, although the technology herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the technology. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the technology.