Medical tube and method of manufacturing the same

Abstract

The present disclosure relates to medical tubing and methods of manufacturing medical tubing. The tubing can be a composite structure made from two or more dissimilar components that are helically wound to form an elongate tube. For example, one of the components can be a helically wound elongate hollow body, and the other component can be an elongate structural component that is also helically wound between the turns of the helically wound hollow body. However, the tubing need not be made from dissimilar components. For example, an elongate hollow body formed (e.g., extruded) from a single material can be helically wound to form an elongate tube. The elongate hollow body itself can have thin-walled portions and relatively thicker or more rigid reinforcing portions in its transverse cross-section. The tubes can be incorporated into various medical circuits, or can be used for other medical purposes.

Description

[0001] This application is a divisional application of the invention patent application filed on December 4, 2013, with application number 201811092715.9 and title "Medical tube and method of manufacturing thereof".

[0002] Cross-referencing

[0003] This application is filed pursuant to 35 U.S. SC §119(e) with U.S. Provisional Application No. 61 / 733,359, entitled "Medical Tubes and Methods of Manufacturing Thereof"; U.S. Provisional Application No. 61 / 733,360, entitled "Medical Tubes and Methods of Manufacturing Thereof"; U.S. Provisional Application No. 61 / 877,622, entitled "Medical Tubes and Methods of Manufacturing Thereof"; U.S. Provisional Application No. 61 / 877,566, entitled "Humidification System"; and U.S. Provisional Application No. 61 / 877,566, entitled "Connections for Humidification Systems". The benefits of priority of U.S. Provisional Application No. 61 / 877,784 entitled “HUMIDIFICATION SYSTEM”; and U.S. Provisional Application No. 61 / 877,736 entitled “ZONE HEATING FOR RESPIRATORY CIRCUITS”, filed September 13, 2013, are each incorporated herein by reference in their entirety.

[0004] In addition, PCT application number PCT / IB2012 / 001786, filed on May 30, 2012, entitled Medical Tube and Method of Manufacturing Thereof, is also incorporated herein by reference in its entirety. Technical Field

[0005] This disclosure generally relates to tubing suitable for medical use, and more specifically to tubing used in medical circuits suitable for delivering and / or removing gas from a patient, such as in positive airway pressure (PAP), ventilators, anesthesia, ventilators, and blowing systems. Background Technology

[0006] In medical circuits, different components deliver warm and / or humidified gases to and from the patient. For example, in some breathing circuits, such as PAP or assisted breathing circuits, the gas inhaled by the patient is delivered from a heated humidifier through an inhalation tube. As another example, the tube can deliver humidified gas (typically CO2) into the abdominal cavity in a blow-through circuit. This can help prevent “dehydration” of the patient’s internal organs and can reduce the amount of time required for postoperative recovery. Unheated tubes allow a significant amount of heat to be lost to natural cooling. This cooling can lead to unwanted condensation or a “rain-washing effect” along the length of the tube delivering warm, humidified air. There is also a need for tubes that can be insulated from heat loss and, for example, can have improved temperature and / or humidity control in medical circuits. Therefore, the object of the present invention is to overcome or improve one or more of the disadvantages of the prior art or at least provide the public with a useful alternative. Summary of the Invention

[0007] Medical tubing and methods of manufacturing medical tubing are disclosed herein in various embodiments. In some embodiments, the tubing may be a composite structure made of two or more dissimilar components helically wound to form an elongated tubing. For example, one of these components may be a helically wound elongated hollow body, and the other components may be elongated structural components similarly helically wound between multiple turns of the helically wound hollow body. In other embodiments, the tubing need not be made of dissimilar components. For example, an elongated hollow body formed from a single material (e.g., extruded) may be helically wound to form an elongated tubing. The elongated hollow body itself may have thin-walled portions and relatively thicker or more rigid reinforcing portions in its transverse cross-section. These tubings may be incorporated into various medical circuits or may be used for other medical applications.

[0008] In at least one embodiment, the composite tube may include a first elongation member comprising a hollow body helically wound to at least partially form the elongated tube, the elongated tube having a longitudinal axis, a lumen extending along the longitudinal axis, and a hollow wall surrounding the lumen. A second elongation member may be helically wound and coupled between adjacent turns of the first elongation member, the second elongation member forming at least a portion of the lumen of the elongated tube. The names “first elongation member” and “second elongation member” do not necessarily imply an order, such as the order in which these components are assembled. As described herein, the first elongation member and the second elongation member may also be multiple parts of a single tubular element.

[0009] In different embodiments, the aforementioned components have one, some, or all of the following characteristics, as well as the characteristics described elsewhere in this disclosure.

[0010] The first elongated member may be a tube. The first elongated member may form multiple bubbles in its longitudinal section, these bubbles having flat surfaces on the lumen. Adjacent bubbles may be separated by a gap above the second elongated member, or these adjacent bubbles may not be directly connected to each other. These bubbles may have perforations. The second elongated member may have a longitudinal section that is wider near the lumen and narrows radially from the lumen. Specifically, the second elongated member may have a longitudinal section that is generally triangular, generally T-shaped, or generally Y-shaped. One or more conductive filaments may be embedded or encapsulated within the second elongated member. The one or more conductive filaments may be heating filaments (or more specifically, resistance heating filaments) and / or sensing filaments. The tube may include pairs of conductive filaments, such as two or four conductive filaments. The pairs of conductive filaments may be formed as connecting loops at one end of the composite tube. The one or more conductive filaments may be separated from the lumen wall. In at least one embodiment, the second elongated member may have a longitudinal section that is generally triangular, generally T-shaped, or generally Y-shaped, and one or more conductive filaments may be embedded or encapsulated on opposite sides of the triangular, T-shaped, or Y-shaped section of the second elongated member.

[0011] The aforementioned components according to any or all of the foregoing embodiments may be incorporated into medical circuit components, inhalation tubes, exhalation tubes, PAP components, blowing circuits, breathing components, or surgical components, as well as other applications.

[0012] A method for manufacturing a composite tube is also disclosed. The resulting tube may have one, some, or all of the characteristics described above or elsewhere in this disclosure. In at least one embodiment, the method includes providing a first elongated member comprising a hollow body, and a second elongated member configured to provide structural support for the first elongated member. The second elongated member is helically wound around a mandrel, wherein opposite edge portions of the second elongated member are spaced apart on adjacent sheaths, thereby forming a second elongated member helix. The first elongated member is helically wound around the second elongated member helix such that a plurality of portions of the first elongated member overlap adjacent sheaths of the second elongated member helix, and a portion of the first elongated member is disposed adjacent to the mandrel located in the space between the sheaths of the second elongated member helix, thereby forming the first elongated member helix.

[0013] In various embodiments, the foregoing method may include one, some, or all of the following: The method may include supplying air at a pressure greater than atmospheric pressure to one end of the first elongated member. The method may include cooling the second elongated member spiral and the first elongated member spiral to form a composite tube having a lumen extending along a longitudinal axis and a hollow space surrounding the lumen. The method may include forming the first elongated member. The method may include extruding the first elongated member using a first extruder. The method may include forming the second elongated member. The method may include extruding the second elongated member using a second extruder. The second extruder may be configured to encapsulate one or more conductive filaments in the second elongated member. Forming the second elongated member may include embedding the conductive filaments in the second elongated member. These conductive filaments may not react with the second elongated member. These conductive filaments may include an alloy of aluminum or copper or other conductive materials. The method may include forming paired conductive filaments into a connecting loop at one end of the composite tube. The first extruder may be different from the second extruder.

[0014] A medical tube is also disclosed. In at least one embodiment, the tube includes an elongated hollow body formed by helical winding, the elongated tube having a longitudinal axis, a lumen extending along the longitudinal axis, and a hollow wall surrounding the lumen, wherein the elongated hollow body has a wall defining at least a portion of the hollow body in its transverse cross-section. The tube may further include a reinforcing portion extending along the length of the elongated hollow body and helically positioned between adjacent turns of the elongated hollow body, wherein the reinforcing portion forms part of the lumen of the elongated tube. The reinforcing portion may be relatively thicker or more rigid than the wall of the elongated hollow body.

[0015] In various embodiments, the aforementioned tube has one, some, or all of the following characteristics, as well as those described elsewhere in this disclosure. The reinforcing portion may be formed from the same sheet of material as the elongated hollow body. The elongated hollow body may include two reinforcing portions in its transverse cross-section, located on opposite sides of the elongated hollow body, wherein the helical winding of the elongated hollow body bonds adjacent reinforcing portions together such that the opposite edges of these reinforcing portions contact each other on adjacent loops of the elongated hollow body. The opposite edges of these reinforcing portions may overlap on adjacent loops of the elongated hollow body. The reinforcing portions and the elongated hollow body may be made from separate sheets of material. The hollow body may form a plurality of bubbles in its longitudinal cross-section, these bubbles having flat surfaces on the lumen. These bubbles may have perforations. The medical tube may also include one or more conductive filaments embedded or encapsulated within the reinforcing portion. The conductive filaments may be heating filaments and / or sensing filaments. The medical tube may include two conductive filaments, with one conductive filament embedded or encapsulated in each reinforcing portion. The medical tube may include two conductive filaments positioned on only one side of the elongated hollow body. The paired conductive filaments may be formed as a connecting loop at one end of the composite tube. The one or more filaments may be spaced apart from the lumen wall.

[0016] The aforementioned tubes according to any or all of the foregoing embodiments can be incorporated into medical circuit components, inhalation tubes, exhalation tubes, PAP components, blowing circuits, breathing components, or surgical components, as well as other applications.

[0017] A method for manufacturing a medical tube is also disclosed. In at least one embodiment, the method includes: helically winding an elongated hollow body around a mandrel to form an elongated tube having a longitudinal axis, a lumen extending along the longitudinal axis, and a hollow wall surrounding the lumen, wherein the elongated hollow body has a wall in its transverse section defining at least a portion of the hollow body; and two reinforcing portions on opposite sides of the elongated body forming part of the lumen wall, the two reinforcing portions being relatively thicker or more rigid than the wall defining at least a portion of the hollow body. The method may further include joining adjacent reinforcing portions together such that the opposite edges of these reinforcing portions contact each other on adjacent loops of the elongated hollow body.

[0018] In various embodiments, the foregoing method may include one, some, or all of the following characteristics, as well as any other characteristics described elsewhere in this disclosure. Joining adjacent reinforcing portions together may cause the edges of these reinforcing portions to overlap. The method may further include supplying air at a pressure greater than atmospheric pressure to one end of the elongated hollow body. The method may further include cooling the elongated hollow body to cause the adjacent reinforcing portions to join together. The method may further include extruding the elongated hollow body. The method may further include embedding conductive filaments within these reinforcing portions. The method may further include forming a connecting loop of paired conductive filaments at one end of the elongated tube.

[0019] A breathing tube is also disclosed. In at least one embodiment, the tube includes a first elongating member comprising a hollow body helically wound to at least partially form the elongated tube, the elongated tube having a longitudinal axis, a lumen extending along the longitudinal axis, and a hollow wall surrounding the lumen, the wall having an inner portion proximal to the lumen and an outer portion opposite to the lumen, wherein the inner portion of the wall has a smaller thickness than the outer portion of the wall.

[0020] In various embodiments, the aforementioned breathing tube may include one, some, or all of the following characteristics, as well as any other characteristics described elsewhere in this disclosure. The breathing tube may further include a second elongated member that is helically wound and coupled between adjacent turns of the first elongated member, the second elongated member forming at least a portion of the lumen of the elongated tube. The thickness of the outer portion of the wall may be in the range of about 0.14 mm to about 0.44 mm. The thickness of the outer portion of the wall may be about 0.24 mm. The thickness of the inner portion of the wall may be in the range of about 0.05 mm to about 0.30 mm. The thickness of the inner portion of the wall may be about 0.10 mm.

[0021] A breathing tube is also disclosed. In at least one embodiment, the tube includes a first elongating member comprising a hollow body helically wound to at least partially form the elongated tube, the elongated tube having a longitudinal axis, a lumen extending along the longitudinal axis, and a hollow wall surrounding the lumen, the hollow body forming a plurality of bubbles in its longitudinal section, the bubbles having a maximum width along the longitudinal axis and a maximum height perpendicular to the longitudinal axis between the outward-facing apex of the wall and the lumen, wherein the ratio of the maximum height to the maximum width is at least about 0.16.

[0022] In various embodiments, the aforementioned breathing tube may include one, some, or all of the following characteristics, as well as any other characteristics described elsewhere in this disclosure. The breathing tube may further include a second elongated member that is helically wound and coupled between adjacent turns of the first elongated member, the second elongated member forming at least a portion of the lumen of the elongated tube. The maximum height may be in the range of about 1.2 mm to about 8.2 mm. The maximum height may be about 3.2 mm. The maximum width may be in the range of about 3.5 mm to about 7.5 mm. The maximum width may be about 5.5 mm. The ratio of the maximum height to the maximum width may be greater than 1.0.

[0023] A breathing tube is also disclosed. In at least one embodiment, the tube includes a first elongating member comprising a hollow body helically wound to at least partially form the elongated tube, the elongated tube having a longitudinal axis, a lumen extending along the longitudinal axis, and a hollow wall surrounding the lumen, the hollow body forming a plurality of bubbles in its longitudinal section, wherein the vertical distance between corresponding points on adjacent bubbles defines a pitch, wherein the ratio of the pitch to the maximum outer diameter of the composite tube is less than about 0.35.

[0024] In various embodiments, the aforementioned breathing tube may include one, some, or all of the following characteristics, as well as any other characteristics described elsewhere in this disclosure. The breathing tube may further include a second elongated member that is helically wound and coupled between adjacent turns of the first elongated member, the second elongated member forming at least a portion of the lumen of the elongated tube. The pitch may be in the range of about 1.2 mm to about 8.1 mm. The pitch may be about 5.1 mm. The maximum outer diameter may be in the range of about 19.5 mm to about 25.5 mm. The maximum outer diameter may be about 22.5 mm.

[0025] A composite tube is also disclosed. In at least one embodiment, the tube includes a first elongating member comprising a hollow body helically wound to at least partially form the elongated tube, the elongated tube having a longitudinal axis, a lumen extending along the longitudinal axis, and a hollow wall surrounding the lumen, the hollow body forming a plurality of bubbles in its longitudinal section, the bubbles having a maximum height perpendicular to the longitudinal axis between the outward-facing apex of the wall and the lumen, the maximum height defining the maximum height of the first elongating member; and a second elongating member helically wound and coupled between adjacent turns of the first elongating member, the second elongating member forming at least a portion of the lumen of the elongated tube, the second elongating member having a maximum height perpendicular to the longitudinal axis between the outward-facing apex of the second elongating member and the lumen, wherein the ratio of the difference between the maximum height of the first elongating member and the maximum height of the second elongating member to the maximum outer diameter of the composite tube is less than about 0.049:1.

[0026] In various embodiments, the aforementioned composite tube may include one, some, or all of the following characteristics, as well as any other characteristics described elsewhere in this disclosure. The wall may have an inner portion proximal to the lumen and an outer portion opposite to the lumen, and the inner portion of the wall has a smaller thickness than the outer portion of the wall.

[0027] A composite tube is also disclosed. In at least one embodiment, the tube includes a first elongating member comprising a hollow body helically wound to at least partially form the elongated tube, the elongated tube having a longitudinal axis, a lumen extending along the longitudinal axis, and a hollow wall surrounding the lumen having an inner portion proximal to the lumen and an outer portion opposite to the lumen; and a second elongating member helically wound between adjacent turns of the first elongating member, the second elongating member forming at least a portion of the lumen of the elongated tube, and the first elongating member engaging at connection points on adjacent turns of the second elongating member; wherein the bending radius of the composite tube is limited by the length of the outer portion between these connection points.

[0028] In various embodiments, the aforementioned composite tube may include one, some, or all of the following characteristics, as well as any other characteristics described elsewhere in this disclosure. The wall has an inner portion proximal to the lumen and an outer portion opposite to the lumen, and the inner portion of the wall has a smaller thickness than the outer portion of the wall.

[0029] A breathing tube is also disclosed. In at least one embodiment, the tube includes a first elongation member comprising a hollow body component, wherein the weight / length of the tube within at least a 300 mm portion closest to one end of the tube is less than about 0.08 g / mm.

[0030] In various embodiments, the aforementioned breathing tube may include one, some, or all of the following characteristics, as well as any other characteristics described elsewhere in this disclosure. The first elongating member may include a hollow body of an elongated tube formed at least partially by helical winding, the elongated tube having a longitudinal axis, a lumen extending along the longitudinal axis, and a hollow wall surrounding the lumen. The breathing tube may further include a second elongating member, which is helically wound and coupled between adjacent turns of the first elongating member, the second elongating member forming at least a portion of the lumen of the elongated tube. The breathing tube may include one or more conductive filaments embedded or encapsulated within the second elongating member. At least one of the one or more conductive filaments may be a heating filament. At least one of the one or more conductive filaments may be a sensing filament. The mass of the tube within 300 mm of one end of the tube may be less than about 24 g. The weight / length of the tube within at least a portion of 300 mm of one end of the tube may be less than about 0.06 g / mm. The mass of the tube within 300 mm of its closest end can be less than approximately 16 g. The thickness of the wall can be at most approximately 0.50 mm.

[0031] A breathing tube is also disclosed. In at least one embodiment, the tube includes a first elongating member comprising a hollow body helically wound to at least partially form the elongated tube, the elongated tube having a longitudinal axis, a lumen extending along the longitudinal axis, and a hollow wall surrounding the lumen, the wall having an inner portion proximal to the lumen and an outer portion opposite to the lumen, wherein in at least a portion of the composite tube, when a force is applied to the outer portion of the wall with a 2.5 mm probe until the outer portion of the wall contacts the inner portion, the outer portion deflects a vertical distance satisfying the following equation: D > 0.5 × F 2.5 Where D represents the vertical distance in millimeters, and F 2.5 This indicates the force, measured in Newtons, applied by the 2.5mm probe.

[0032] In various embodiments, the aforementioned breathing tube may include one, some, or all of the following characteristics, as well as any other characteristics described elsewhere in this disclosure. The breathing tube may further include a second elongated member that is helically wound and coupled between adjacent turns of the first elongated member, the second elongated member forming at least a portion of the lumen of the elongated tube. When a force of approximately 1 N is applied with a 2.5 mm probe, this outer portion may deflect more than approximately 1 mm.

[0033] Also disclosed is a catheter suitable for use with a tube for delivering humidifying gas to a patient. In at least one embodiment, the catheter includes a connector configured to be connected to the tube, the connector including a lumen extending along a longitudinal axis and walls surrounding the lumen, the lumen defining a flow path for humidifying gas in use; and a printed circuit board assembly including a printed circuit board, and further including a segmented portion embedded in the walls of the connector and extending through the lumen of the connector along a diameter or chord, such that the segmented portion substantially divides at least a portion of the flow path in two, at least a portion of the segmented portion being overmolded with an overmolding composition, wiring portions adjacent to the segmented portion and projecting outward from the walls of the connector in a direction away from the lumen of the connector, and a sensor portion disposed in the lumen of the connector and projecting from the segmented portion along the longitudinal axis, the sensor portion including at least one sensor, and the sensor portion being overmolded with the overmolding composition.

[0034] In various embodiments, the aforementioned conduit may include one, some, or all of the following characteristics, as well as any other characteristics described elsewhere in this disclosure. The printed circuit board assembly may further include a support portion adjacent to the segmented portion and projecting outward from the connector in a direction away from the lumen and opposite to the wiring portion. The wiring portion may be configured to be electrically connected from the conduit to one or more heating wires. The at least one sensor may include a thermistor. The sensor portion may project upstream of the flow path. The at least one sensor may include a sensor adjacent to the upstream leading edge of the sensor portion. The sensor portion may project downstream of the flow path. The at least one sensor may include a sensor adjacent to the downstream leading edge of the sensor portion. The overmolded composition proximal to the sensor portion may have a tapered shape extending along the longitudinal axis. The overmolded portion may be thinnest proximal to the leading edge of the sensor portion. The sensor portion may have a wing-like shape extending along the longitudinal axis. The sensor portion may have a bullet or torpedo shape.

[0035] A breathing duct is also disclosed. In at least one embodiment, the duct includes a lumen extending along a longitudinal axis and a wall surrounding the lumen, the lumen defining a gas flow path during use; and an overmolded printed circuit board assembly fixed to the wall, the printed circuit board assembly including a printed circuit board, and further including a mounting portion disposed in the lumen of the connector and projecting along the longitudinal axis, and a temperature sensor on the surface of the mounting portion.

[0036] In various embodiments, the aforementioned conduit may include one, some, or all of the following characteristics, as well as any other characteristics described elsewhere in this disclosure. The temperature sensor may be a thermistor.

[0037] A breathing duct is also disclosed. In at least one embodiment, the duct includes a lumen extending along a longitudinal axis and walls surrounding the lumen, the lumen defining a gas flow path during use; and a component attached to these walls and extending through the lumen along a diameter or chord, such that the component substantially divides at least a portion of the flow path in two, the component including a mounting portion disposed in the lumen and projecting along the longitudinal axis; a temperature sensor on the surface of the mounting portion; and an electrical connection on the sensor.

[0038] In various embodiments, the aforementioned conduit may include one, some, or all of the following characteristics, as well as any other characteristics described elsewhere in this disclosure. The temperature sensor may be a thermistor. The component may be a printed circuit board. The electrical connection may span the length of the component along the diameter or chord.

[0039] A breathing duct is also disclosed. In at least one embodiment, the duct includes a lumen extending along a longitudinal axis and a wall surrounding the lumen, the lumen defining a gas flow path during use; and an overmolded printed circuit board assembly fixed to the wall, the printed circuit board assembly including a printed circuit board, and further including a mounting portion disposed in the lumen and projecting along the longitudinal axis, and a temperature sensor on the surface of the mounting portion, wherein the overmolded portion proximal to the mounting portion has a tapered shape.

[0040] In various embodiments, the aforementioned conduit may include one, some, or all of the following characteristics, as well as any other characteristics described elsewhere in this disclosure. The temperature sensor may be a thermistor.

[0041] A breathing duct is also disclosed. In at least one embodiment, the duct includes a lumen extending along a longitudinal axis and a wall surrounding the lumen, the lumen defining a gas flow path during use; and a component connected to the wall, including a mounting portion disposed in the lumen and projecting along the longitudinal axis, the mounting portion including a temperature sensor longitudinally positioned upstream of a connection on the wall.

[0042] In various embodiments, the aforementioned breathing tube may include one, some, or all of the following characteristics, as well as any other characteristics described elsewhere in this disclosure. The temperature sensor may be a thermistor. The temperature sensor may be located proximal to the upstream end of the mounting portion. The mounting portion may be overmolded. The overmolded portion may be thinnest proximal to the temperature sensor. The mounting portion may project longitudinally downstream. The mounting portion may have a wing-like shape extending along the longitudinal axis. The mounting portion may have a bullet or torpedo shape. The vertical distance between the mounting portion and the wall may be at least 30% of the diameter of the lumen.

[0043] A breathing duct segment is also disclosed. In at least one embodiment, the segment includes a lumen extending along a longitudinal axis and a wall surrounding the lumen, the lumen defining a gas flow path during use; and a printed circuit board assembly including a printed circuit board and including a first portion extending through the lumen along a diameter or chord, such that a portion of the printed circuit board assembly substantially divides at least a portion of the flow path in two, the first portion being overmolded with an overmolding composition, and a second portion adjacent to the first portion projecting outward from the wall in a direction away from the lumen, the second portion including one or more connection pads on the printed circuit board, the one or more... A connecting pad is configured to receive one or more metal wires from a first component, and a third portion adjacent to the first portion protrudes outward from the wall in a direction away from the lumen and in a direction opposite to the second portion. The third portion includes one or more connecting pads on the printed circuit board. The one or more connecting pads are configured to receive one or more metal wires from a second component different from the first component, and one or more conductive tracks on the printed circuit board are electrically coupled to the one or more connecting pads of the second portion and the one or more connecting pads of the third portion, and are configured to provide an electrical connection between the first component and the second component.

[0044] In different embodiments, the foregoing section may include one, some, or all of the following characteristics, as well as any other characteristics described elsewhere in this disclosure. The first component may be a breathing tube. The second component may be a breathing tube. The printed circuit board assembly may further include a mounting portion disposed within the lumen of the connector and projecting along the longitudinal axis, and a temperature sensor on the surface of the mounting portion.

[0045] In various embodiments, the breathing tube includes a first elongating member comprising a hollow body helically wound to at least partially form the elongated tube, the elongated tube having a longitudinal axis, a lumen extending along the longitudinal axis, and a hollow wall surrounding the lumen. The hollow body forms a plurality of bubbles in its longitudinal cross-section, the bubbles having a maximum width along the longitudinal axis and a maximum height perpendicular to the longitudinal axis between the outward-facing apex of the wall and the lumen, wherein the ratio of the maximum height to the maximum width is at least about 0.16. A second elongating member may be helically wound and joined between adjacent turns of the first elongating member, the second elongating member forming at least a portion of the lumen of the elongated tube. The maximum height may be in the range of about 0.7 mm to about 7.7 mm. The maximum height may be about 2.7 mm. The maximum width may be in the range of about 2.0 mm to about 6.0 mm. The maximum width may be about 4.0 mm. The ratio of the maximum height to the maximum width may be greater than 1.0.

[0046] In various embodiments, the breathing tube includes a first elongating member comprising a hollow body helically wound to at least partially form the elongated tube, the elongated tube having a longitudinal axis, a lumen extending along the longitudinal axis, and a hollow wall surrounding the lumen. The hollow body forms a plurality of bubbles in its longitudinal section, wherein the vertical distance between corresponding points on adjacent bubbles defines a pitch, wherein the ratio of the pitch to the maximum outer diameter of the composite tube is less than about 0.35. A second elongating member may be helically wound and coupled between adjacent turns of the first elongating member, the second elongating member forming at least a portion of the lumen of the elongated tube. The pitch may be in the range of about 1.2 mm to about 8.1 mm. The pitch may be about 5.1 mm. The maximum outer diameter may be in the range of about 19.5 mm to about 25.5 mm. The maximum outer diameter may be about 22.5 mm.

[0047] In various embodiments, the composite tube includes a first elongation member comprising a hollow body helically wound to at least partially form the elongation tube, the elongation tube having a longitudinal axis, a lumen extending along the longitudinal axis, and a hollow wall surrounding the lumen, the hollow body forming a plurality of bubbles in its longitudinal section, the bubbles having a maximum height perpendicular to the longitudinal axis between the outward-facing apex of the wall and the lumen, the maximum height defining the maximum height of the first elongation member; and a second elongation member helically wound and coupled between adjacent turns of the first elongation member, the second elongation member forming at least a portion of the lumen of the elongation tube, the second elongation member having a maximum height perpendicular to the longitudinal axis between the outward-facing apex of the second elongation member and the lumen, wherein the ratio of the difference between the maximum height of the first elongation member and the maximum height of the second elongation member to the maximum outer diameter of the composite tube is less than about 0.049:1. The wall may have an inner portion near the lumen and an outer portion away from the lumen, and the inner portion of the wall may have a smaller thickness than the outer portion of the wall.

[0048] In various embodiments, the composite tube includes a first elongating member comprising a hollow body helically wound to at least partially form the elongated tube, the elongated tube having a longitudinal axis, a lumen extending along the longitudinal axis, and a hollow wall surrounding the lumen, the wall having an inner portion proximal to the lumen and an outer portion opposing the lumen; and a second elongating member helically wound between adjacent turns of the first elongating member, the second elongating member forming at least a portion of the lumen of the elongated tube, and the first elongating member engaging at connection points on adjacent turns of the second elongating member; wherein the bending radius of the composite tube is limited by the length of the outer portion between these connection points. The wall may have an inner portion proximal to the lumen and an outer portion opposing the lumen, and the inner portion of the wall may have a smaller thickness than the outer portion of the wall.

[0049] In various embodiments, a catheter suitable for use with a tube for delivering humidifying gas to a patient is provided, the catheter including a connector configured to be connected to the tube, the connector including a lumen extending along a longitudinal axis and walls surrounding the lumen, the lumen defining a flow path for the humidifying gas in use; and a printed circuit board assembly including a printed circuit board, and further including a segmented portion embedded in the walls of the connector and extending through the lumen of the connector along a diameter or chord, such that the segmented portion substantially divides at least a portion of the flow path in two, at least a portion of the segmented portion being overmolded with an overmolding composition, wiring portions adjacent to the segmented portion and projecting outward from the walls of the connector in a direction away from the lumen of the connector, and a sensor portion disposed in the lumen of the connector and projecting from the segmented portion along the longitudinal axis, the sensor portion including at least one sensor, and the sensor portion being overmolded with the overmolding composition. The printed circuit board assembly may further include a support portion adjacent to the segmented portion and projecting outward from the connector in a direction away from the lumen and opposite to the wiring portion. The wiring portion may be configured to be electrically connected from the conduit to one or more heating wires. The at least one sensor may include a thermistor. The sensor portion may protrude upstream of the flow path. The at least one sensor may include a sensor adjacent to the upstream leading edge of the sensor portion. The sensor portion may protrude downstream of the flow path. The at least one sensor may include a sensor adjacent to the downstream leading edge of the sensor portion. The overmolding composition proximal to the sensor portion may have a tapered shape extending along the longitudinal axis. The overmolding portion may be thinnest proximal to the leading edge of the sensor portion. The sensor portion may have a wing-like shape extending along the longitudinal axis. The sensor portion may have a bullet or torpedo shape.

[0050] In various embodiments, the breathing tube includes a lumen extending along a longitudinal axis and a wall surrounding the lumen, which defines a gas flow path during use; and an overmolded printed circuit board assembly fixed to the wall, the overmolded circuit board assembly including a printed circuit board, and further including a mounting portion disposed in the lumen and projecting along the longitudinal axis, and a temperature sensor on the surface of the mounting portion, wherein the overmolded portion proximal to the mounting portion has a tapered shape. The temperature sensor may be a thermistor.

[0051] In various embodiments, the breathing tube includes a lumen extending along a longitudinal axis and a wall surrounding the lumen, the lumen defining a gas flow path during use; and a component connected to the wall, including a mounting portion disposed within the lumen and projecting along the longitudinal axis, the mounting portion including a temperature sensor positioned longitudinally upstream of a connection to the wall. The temperature sensor may be a thermistor. The temperature sensor may be proximal to the upstream end of the mounting portion. The mounting portion may be overmolded. The overmolded portion may be thinnest proximal to the temperature sensor. The mounting portion may project longitudinally downstream. The mounting portion may have a wing-like shape extending along the longitudinal axis. The mounting portion may have a bullet or torpedo shape. The vertical distance between the mounting portion and the wall may be at least 30% of the diameter of the lumen.

[0052] In various embodiments, the breathing tubing segment includes a lumen extending along a longitudinal axis and a wall surrounding the lumen, the lumen defining a gas flow path during use; and a printed circuit board assembly including a printed circuit board and a first portion extending through the lumen along a diameter or chord, such that a portion of the printed circuit board assembly substantially divides at least a portion of the flow path in two, the first portion being overmolded with an overmolding composition, and a second portion adjacent to the first portion projecting outward from the wall in a direction away from the lumen, the second portion including one or more connection pads on the printed circuit board. A connecting pad is configured to receive one or more metal wires from a first component. A third portion adjacent to the first portion protrudes outward from the wall in a direction away from the lumen and opposite to the second portion. The third portion includes one or more connecting pads on the printed circuit board. These connecting pads are configured to receive one or more metal wires from a second component different from the first component. One or more conductive tracks on the printed circuit board are electrically coupled to the connecting pads of the second portion and the third portion, and are configured to provide an electrical connection between the first and second components. The first component may be a breathing tube. The second component may be a breathing tube. The printed circuit board assembly may further include a mounting portion disposed within the lumen of the connector and protruding along the longitudinal axis, and a temperature sensor on the surface of the mounting portion.

[0053] In various embodiments, the composite tube includes a first elongated member comprising a hollow body helically wound to at least partially form the elongated tube, the elongated tube having a longitudinal axis, a lumen extending along the longitudinal axis, and a hollow wall surrounding the lumen; and a second elongated member helically wound and coupled between adjacent turns of the first elongated member, the second elongated member forming at least a portion of the lumen of the elongated tube; wherein at least a portion of the first elongated member is formed of a breathable material. In one example, the composite tube may be provided with a humidifying fluid source and / or pre-filled with a certain volume of humidifying fluid, and a heater may be provided to heat the fluid, such that fluid vapor passes through the breathable material into or out of the lumen. The heater may include one or more heating filaments disposed in the second elongated member.

[0054] To summarize the invention, certain aspects, advantages, and novel features of the invention are described herein. It should be understood that not all of these advantages can necessarily be achieved by any particular embodiment of the invention. Therefore, the invention can be embodied or practiced in a manner that achieves or optimizes one or more advantages as taught herein, without requiring the realization of other advantages as may be taught or suggested herein. Attached Figure Description

[0055] Exemplary embodiments of various features of the disclosed systems and methods will now be described with reference to the accompanying drawings. The drawings and associated descriptions are provided to illustrate embodiments and are not intended to limit the scope of this disclosure.

[0056] Figure 1 A schematic diagram of a medical circuit incorporating one or more medical tubes is shown.

[0057] Figure 2A A side-view top view of a cross-section of an example composite pipe is shown.

[0058] Figure 2B The longitudinal section of the top portion of the tube is shown, which is related to... Figure 2A Similar to the example composite pipe.

[0059] Figure 2C Another longitudinal section is shown, which illustrates the first elongated member in the composite tube.

[0060] Figure 2D Another longitudinal section of the top portion of the tube is shown.

[0061] Figure 2E Another longitudinal section of the top portion of the tube is shown.

[0062] Figure 2FThe tube is shown, with a portion of it exposed in its longitudinal section.

[0063] Figure 2G The longitudinal section of a portion of the pipe is shown, which is related to... Figure 2F The example tube is similar.

[0064] Figure 2H The longitudinal section of the top portion of the tube is shown.

[0065] Figure 3 A fixture suitable for determining the deflection of bubbles is shown.

[0066] Figure 4 The curves showing the deflection of the force on the bubble are shown.

[0067] Figure 5A –5C shows an example of the shape of a first elongated member configured to improve thermal efficiency.

[0068] Figure 5D –5F shows an example of a filament arrangement configured to improve thermal efficiency.

[0069] Figure 6A A longitudinal section of a portion of the composite pipe in a neutral position is shown.

[0070] Figure 6B It shows the bent position. Figure 6A The composite tube portion, in which the composite tube has been bent into a ∩ shape.

[0071] Figure 6C The composite tube, bent into a ∩ shape, is shown.

[0072] Figure 6D The image shows a composite pipe that has been bent beyond its minimum radius of curvature.

[0073] Figure 7A The transverse section of the second elongated member in the composite tube is shown.

[0074] Figure 7B Another transverse section of the second elongated member is shown.

[0075] Figure 7C Another example of a second elongated member is shown.

[0076] Figure 7D Another example of a second elongated member is shown.

[0077] Figure 7E Another example of a second elongated member is shown.

[0078] Figure 7F Another example of a second elongated member is shown.

[0079] Figure 7G Another example of a second elongated member is shown.

[0080] Figure 8A A schematic diagram of a composite tube with variable pitch is shown.

[0081] Figure 8B This is a graph depicting an example temperature profile in a variable pitch composite tube.

[0082] Figure 9A A schematic diagram of the front top section of the elastic clamp is shown.

[0083] Figure 9B It shows Figure 9A A detailed front top view of the rollers on the elastic clamp.

[0084] Figure 9C –9F shows the elastic clamp in use. Figure 9C and Figure 9E A front perspective view of the sample under test in the fixture is shown. Figure 9D and Figure 9F A rear perspective view of the sample under test in the fixture is shown.

[0085] Figure 10A A clamp for testing compressive strength is shown.

[0086] Figure 10B A graph showing the load relative to the extension is presented to determine the compression stiffness.

[0087] Figure 11A –11D demonstrates the radius of curvature characteristics of the tube.

[0088] Figure 12A –12C shows an example of a stack of first elongated members.

[0089] Figure 13 An alternative embodiment of the second elongation member is shown.

[0090] Figure 14A –14E shows several variations of the tube that are adapted to provide increased lateral extension of the tube.

[0091] Figure 15A –15E respectively show Figure 14A –14E shows the extended state of the tube.

[0092] Figure 16 An example medical circuit according to at least one embodiment is shown.

[0093] Figure 17 An air blowing system according to at least one embodiment is shown.

[0094] Figure 18 This is a schematic diagram of a coaxial tube according to at least one embodiment.

[0095] Figure 19A –19B shows a composite tube used with a patient interface.

[0096] Figure 20A A composite tube is shown for use with a full-face mask.

[0097] Figure 20B The composite tube used with the nasal mask is shown.

[0098] Figure 20C A composite tube for use with a nose mask / pillow cover is shown.

[0099] Figure 21A One aspect of a method for forming a composite pipe is shown.

[0100] Figure 21B The second elongated member is shown in a spiral wound design.

[0101] Figure 21C Another aspect of a method for forming composite pipes is shown.

[0102] Figure 21D Another aspect of a method for forming composite pipes is shown.

[0103] Figure 21E Another aspect of a method for forming composite pipes is shown.

[0104] Figure 21F Another aspect of a method for forming composite pipes is shown.

[0105] Figure 22A –22C shows an example construction of a longitudinal section of multiple tubes.

[0106] Figure 23A –23H illustrates an alternative method for forming a tube.

[0107] Figure 24A –24B illustrates another example of a single elongated hollow body spirally wound to form a medical tube.

[0108] Figure 24C –24F shows examples of other single elongated hollow bodies that are spirally wound to form a medical tube.

[0109] Figure 25A–25L shows a general flowchart as well as more detailed schematics and photographs, relating to a method for attaching a connector to the end of a tube configured to connect to a humidifier in use.

[0110] Figure 26A –26E shows a connector for attaching a filament to an electrical connector.

[0111] Figure 27A -27E shows a design suitable for use with Figure 25A Clamshell-shaped fitting used with a 25L connector.

[0112] Figure 28A -28F and Figure 29A –29L shows connectors that can be used in methods with medical circuits through which wires pass and associated components.

[0113] Figure 30A –30O shows a schematic diagram of a connector adapted to attach a tube to a patient interface.

[0114] Figure 31A –31B shows a design suitable for use with Figure 30A The top part used with the -30O connector.

[0115] Figure 32A –32D shows a design suitable for use with Figure 30A An anti-rotation structure part used with a -30° connector.

[0116] Figure 33A –33D shows an example PCB assembly.

[0117] Figure 34 A segmented intake section for use with a humidification system is shown, which has an intermediate connector configured to couple heating filaments and / or temperature sensors within two sections.

[0118] Figure 35A –35E shows a schematic diagram of a connector adapted to attach a tube to a humidifier port, patient interface, or any other suitable component.

[0119] Figure 36A –36K shows a schematic diagram of another connector adapted to attach the tube to a humidifier port, patient interface, or any other suitable component.

[0120] Figure 37A A longitudinal section of the top portion of the tube is shown, which includes two first elongation members.

[0121] Figure 37BAnother longitudinal section of the top portion of the tube is shown, which includes two first elongation members.

[0122] Reference numerals are generally reused throughout these figures to indicate correspondence between referenced (or similar) elements. However, corresponding referenced (or similar) elements may have different reference numerals in some cases. Furthermore, one or more of the first digits of each reference numeral typically indicate the figure in which the element first appears. Specific Implementation

[0123] The following description, with reference to the accompanying drawings, details several illustrative embodiments for implementing the apparatus and methods described herein. The invention is not limited to these described embodiments.

[0124] Breathing circuit including one or more medical tubes

[0125] To understand this disclosure in more detail, please refer first to... Figure 1 This illustrates a breathing circuit according to at least one embodiment, comprising one or more medical tubes. "Tube" is a broad term and is given its general and conventional meaning to those skilled in the art (i.e., it is not limited to a specific or custom meaning), and includes, but is not limited to, cylindrical and non-cylindrical channels. Some embodiments may incorporate a composite tube, which can generally be defined as comprising two or more parts, or specifically, in some embodiments, a tube comprising two or more components, as described in more detail below. Such a breathing circuit may be a continuous, variable, or bi-level positive airway pressure (PAP) system or another form of respiratory therapy.

[0126] It can be done as follows: Figure 1 The gas is transported in the circuit. Dry gas is delivered from the ventilator / fan 105 to the humidifier 107, which humidifies the dry gas. The humidifier 107 is connected via port 111 to the inlet 109 (the end for receiving humidified gas) of the inspiratory tube 103, thereby supplying humidified gas to the inspiratory tube 103. The inspiratory tube is a tube configured to deliver breathing gas to the patient and may be composed of a composite tube as described in further detail below. Gas flows through the inspiratory tube 103 to the outlet 113 (the end for discharging humidified gas) and then subsequently to the patient 101 through the patient interface 115 connected to the outlet 113.

[0127] An exhalation tubing 117 is optionally connected to a patient interface 115. The exhalation tubing is configured to move exhaled humidified gas away from the patient. Here, the exhalation tubing 117 returns exhaled humidified gas from the patient interface 115 to the ventilator / fan 105.

[0128] In this example, dry gas enters the ventilator / blower 105 through vent 119. Fan 121 can improve airflow into the ventilator / blower by drawing air or other gases through vent 119. For example, fan 121 can be a variable speed fan, with electronic controller 123 controlling the fan speed. Specifically, the function of electronic controller 123 can be controlled by electronic master controller 125 in response to inputs from master controller 125 and predetermined desired values ​​(preset values) of pressure, fan speed, or gas flow rate set by the user via dial 127.

[0129] The humidifier 107 includes a humidification chamber 129 containing a volume of water 130 or other suitable humidifying liquid. Preferably, the humidification chamber 129 is removable from the humidifier 107 after use. Removability allows the humidification chamber 129 to be more easily disinfected or disposed of. However, the humidification chamber 129 portion of the humidifier 107 can be a monolithic construction. The body of the humidification chamber 129 can be formed of a non-conductive glass or plastic material. But the humidification chamber 129 may also include multiple conductive components. For example, the humidification chamber 129 may include a highly thermally conductive base (e.g., an aluminum base) that contacts or is associated with the heater plate 131 on the humidifier 107.

[0130] The humidifier 107 may also include multiple electronic controls. In this example, the humidifier 107 includes an electronic analog or digital main controller 125. Preferably, the main controller 125 is a microprocessor-based controller that executes computer software commands stored in associated memory. In response to user-set humidity or temperature values ​​input via, for example, a user interface 133, and other inputs, the main controller 125 determines when (or at what level) to power the heater plate 131 to heat the water 130 within the humidification chamber 129.

[0131] Any suitable patient interface 115 can be used. "Patient interface" is a broad term and is given its general and conventional meaning to those skilled in the art (that is, it is not limited to a specific or custom meaning), and includes, but is not limited to, masks (such as endotracheal masks, face masks, and nasal masks), cannulas, and nasal pillows. Temperature probe 135 can be connected to the inhalation tube 103 near or to the patient interface 115. Temperature probe 135 monitors the temperature in the vicinity of or at the patient interface 115. A heating filament (not shown) associated with the temperature probe can be used to adjust the temperature of the patient interface 115 and / or the inhalation tube 103 to raise the temperature of the inhalation tube 103 and / or the patient interface 115 above its saturation temperature, thereby reducing the chance of unwanted condensation.

[0132] exist Figure 1In this configuration, exhaled humidified gas is returned from the patient interface 115 to the ventilator / fan 105 via the exhalation tubing 117. The exhalation tubing 117 can also be a composite tubing, as described in more detail below. However, the exhalation tubing 117 can also be a medical tubing as previously known in the art. In either case, the exhalation tubing 117 may have a temperature probe and / or heating filament integrated therein (as described above with respect to the inhalation tubing 103), thereby reducing the chance of condensation. Furthermore, the exhalation tubing 117 does not need to return exhaled gas to the ventilator / fan 105. Alternatively, the exhaled humidified gas can be directly delivered to the ambient environment or to other auxiliary devices, such as an air scrubber / filter (not shown). In some embodiments, the exhalation tubing is omitted entirely.

[0133] Composite pipe

[0134] Figure 2A A side-top view of a cross-section of an example composite pipe 201 is shown. Generally, the composite pipe 201 includes a first elongating member 203 and a second elongating member 205. The term "member" is a broad term and is given its common and conventional meaning to those skilled in the art (i.e., it is not limited to a specific or customary meaning), and includes, but is not limited to, integral parts, integral components, and dissimilar components. Therefore, although... Figure 2A An embodiment consisting of two dissimilar components is shown, but it will be understood that in other embodiments (as described below), the first elongated member 203 and the second elongated member 205 may also represent multiple regions in a tube formed of a single material. Thus, the first elongated member 203 may represent a hollow portion of the tube, while the second elongated member 205 may represent a structural support or reinforcement portion of the tube that adds structural support to the hollow portion. The hollow portion and the structural support portion may have a helical construction as described herein.

[0135] The composite tube 201 can be used to form the inspiratory tube 103 and / or expiratory tube 117 in the breathing circuit as described above, or any other tube as described elsewhere in this disclosure. In some embodiments, the composite tube 201 is at least one inspiratory tube 103.

[0136] The components and characteristics of the example composite pipe 201 are described in more detail below. Subheadings such as “First Elongation Member” and “Second Elongation Member” are used. These subheadings are not and should not be considered limiting. For example, many aspects of one or more embodiments described under the subheading “First Elongation Member” may also be applied to one or more embodiments described under the subheading “Second Elongation Member”, and vice versa.

[0137] First elongation member

[0138] exist Figure 2AIn this embodiment, the first elongating member 203 includes a hollow body that is helically wound to at least partially form an elongated tube having a longitudinal axis LA-LA and a lumen 207 (tube hole) extending along the longitudinal axis LA-LA. The first elongating member 203 has an inner portion 211 near the lumen 207. In some embodiments, the surface of the inner portion 211 forms the lumen 207. The first elongating member 203 also has an outer portion 219 opposite to the inner portion and radially away from the lumen 207. As discussed in more detail below, the first elongating member 203 may form a plurality of bubbles in its longitudinal section. In some embodiments, these bubbles have a cross-sectional profile similar to the letter "D". These bubbles may be arcuate on their outward-facing surfaces. These bubbles may be more flattened on the surface of the lumen 207. In at least one embodiment, the first elongating member 203 is a tube.

[0139] Preferably, the first elongated member 203 is flexible. Flexibility refers to the ability to bend. Furthermore, the first elongated member 203 is preferably transparent, or at least translucent or semi-opaque. This transparency allows the caregiver or user to inspect the lumen 207 for blockages or contamination, or to determine the presence of moisture.

[0140] Various plastics, including medical-grade plastics, are suitable for the body of the first elongation member 203. Examples of suitable materials include: polyolefin elastomers, polyetheramide block copolymers, thermoplastic copolyester elastomers, EPDM-polypropylene blends, and thermoplastic polyurethanes. In some embodiments, the material is selected such that the resulting first elongation member 203 has a material density less than or equal to 1 g / cm³. 3 (or approximately 1g / cm) 3 ).

[0141] The material of the first elongating member 203 is preferably soft. Softness reflects the amount of stretching or compression a material undergoes after a force is applied. A soft material stretches or compresses more than a rigid material. Bubble deflection can be used to quantify the softness of the material of the first elongating member 203. Bubble deflection is the distance by which the outer portion 219 of the first elongating member 203 deflects vertically (that is, radially inwardly in the direction of the lumen 207) after a force is applied. A bubble deflection fixture, for example, can be used... Figure 3 The fixture 301 shown in the photo is used to test the deflection of the bubble.

[0142] In a softness test, Figure 3 Four samples of composite tubes having the properties shown in Table 1 (hereinafter referred to as "Type 1") and four samples of composite tubes having the properties shown in Table 2 (hereinafter referred to as "Type 2") were tested on fixture 301.

[0143] Table 1

[0144]

[0145]

[0146] Table 2

[0147]

[0148] A probe 303 with a diameter of 2.5 mm applies force to each sample 305 and measures the deflection of the bubbles. Figure 4 The resulting curves were plotted. Until their respective outer portions 219 contact the inner portions 211, Type 1 samples typically require less force to achieve bubble deflection similar to that of Type 2 samples. In some embodiments, bubble deflection can satisfy the equation: D > 0.5 × F until the outer portions 219 contact the inner portions 211. 2.5 Where D represents bubble deflection in millimeters, and F 2.5 This represents the force, measured in Newtons, applied by a 2.5mm probe. For example, the first elongation member 203 can deflect more than 1mm when a force of 1N is applied with the 2.5mm probe 303 until the outer portion 219 contacts the inner portion 211.

[0149] It should be understood that while the constructions in Table 1 may be preferred in some embodiments, other constructions and variations may be used in other embodiments as desired.

[0150] Figure 2B It shows Figure 2A The longitudinal section of the top portion of the example composite pipe 201. Figure 2B With Figure 2A The same orientation. This example further illustrates the shape of the hollow body of the first elongated member 203. As can be seen in this example, the first elongated member 203 forms a plurality of hollow bubbles in its longitudinal section. Therefore, in this specification, the term "bubble" refers to the cross-sectional shape of a turn or a ring of the first elongated member 203. A portion 209 of the first elongated member 203 overlaps the adjacent sheath of the second elongated member 205. The interior portion 211 of the first elongated member 203 forms the wall of the lumen 207.

[0151] The hollow body structure of the first elongated member 203 contributes to the sound insulation properties of the composite tube 201. In at least one embodiment, the outer diameter of the first elongated member 203 is larger than the outer diameter of the second elongated member 205. The bubble-shaped structure forms a cushion. Therefore, the bubble-shaped first elongated member 203, filled with fluid (gas or liquid), can suppress noise generated when the composite tube 201 is dragged along the edge of an object such as a table or bedside table. In this way, the composite tube 201 can be quieter compared to a one-piece solid corrugated tube.

[0152] The hollow body structure of the first elongated member 203 also contributes to the insulating properties of the composite tube 201. The insulated composite tube 201 is necessary because, as explained above, it prevents heat loss. This allows the composite tube 201 to deliver gas from the heated humidifier to the patient while maintaining the confined state of the gas with minimal energy consumption.

[0153] It was found that gaps 213 were present between adjacent loops of the first elongated member 203, i.e., between adjacent bubbles, which unexpectedly improved the overall insulation properties of the composite tube 201. Therefore, in some embodiments, adjacent bubbles are separated by gaps 213. Furthermore, some embodiments including the provision of gaps 213 between adjacent bubbles increase the thermal resistivity (R value) and thus reduce the thermal conductivity of the composite tube 201. This gap configuration was also found to improve the flexibility of the composite tube 201 by allowing for shorter radii of bending. Triangular second elongated members 205 or T-shaped second elongated members 205, such as... Figure 2B As shown, this helps maintain the gap 213 between adjacent bubbles. Otherwise, in some embodiments, adjacent bubbles are in contact. For example, adjacent bubbles may be bonded together.

[0154] Figure 2C It shows Figure 2B The longitudinal cross-section of the bubble-like material. As shown, the portion 209 of the first elongated member 203 overlapping the adjacent sheath of the second elongated member 205 is characterized by the degree of the bonding area 217. A larger bonding area improves the tube's resistance to delamination at the interface between the first and second elongated members. Alternatively or additionally, the shape of the beads and / or bubbles can be adapted to increase the bonding area 217. For example, Figure 2D The relatively small area of ​​contact is shown on the left-hand side. Figure 5B It also shows a smaller bonding area. Conversely, Figure 2E Having more Figure 2D The bonding region shown is much larger than the bonding region, due to the size and shape of the beads. Figure 5A and Figure 5CA larger bonding area is also shown. Each of these figures will be discussed in more detail below. It should be understood that, although in Figure 2E , Figure 3 and Figure 5C The configuration may be preferred in some embodiments, but other configurations, including those that may be desired, are also acceptable. Figure 2D , Figure 5B Constructions in other variations can be used in other embodiments.

[0155] Figure 2D A longitudinal section of the top portion of another composite pipe is shown. Figure 2D With Figure 2B The same orientation. This example further illustrates the shape of the hollow body of the first elongated member 203 and demonstrates how the first elongated member 203 forms multiple hollow bubbles in its longitudinal section. In this example, these bubbles are completely separated from each other by gaps 213. A generally triangular second elongated member 205 supports the first elongated member 203.

[0156] Figure 2H A longitudinal section of the top portion of another composite pipe is shown. Figure 2H With Figure 2B Same orientation.

[0157] exist Figure 2H In this example, the cross-sectional thickness of the inner portion 211 forming the cavity wall in the first elongated member 203 is less than the thickness of the outer portion 219. Because the first elongated member 203 has a D-shaped bubble profile, the outward-facing portion of the first elongated member 203 has material voids between adjacent turns of the second elongated member, which facilitates the movement and extension of the composite tube 201 when it is bent into a ∩ shape. Figure 2H The construction creates thinner bubbles near the lumen 207, which allows the inner portion 211 to be more easily compressed or “bundled” when the composite tube 201 is bent into a ∩ shape. Therefore, some embodiments include the implementation that a construction in which the cross-sectional thickness of the inner portion 211 is less than the cross-sectional thickness of the outer portion 219 can improve the flexibility of the composite tube 201 by allowing bending with a shorter radius. Furthermore, some embodiments include the implementation that overall tube flexibility can be improved by providing a first elongation member 203 with a variable cross-sectional wall thickness. It is desirable that the thickness of the inner portion 211 is less than the thickness of the outer portion 219.

[0158] In at least one instance, the thickness of the inner portion 211 is at least 20% (or about 20%) less than the thickness of the outer portion 219. For example, in some embodiments, the thickness of the inner portion 211 is at least 30% (or about 30%), at least 40% (or about 40%), at least 50% (or about 50%), or at least 60% (or about 60%) less than the thickness of the outer portion 219. In some embodiments, the thickness of the inner portion 211 is 27% (or about 27%) less than the thickness of the outer portion 219. In some embodiments, the thickness of the inner portion 211 is 32% (or about 32%) less than the thickness of the outer portion 219. In some embodiments, the thickness of the inner portion 211 is 58% (or about 58%) less than the thickness of the outer portion 219. In some embodiments, the thickness of the inner portion 211 is 64% (or about 64%) less than the thickness of the outer portion 219.

[0159] The thickness of the outer portion 219 can be in the range of 0.14 mm (or about 0.14 mm) to 0.44 mm (or about 0.44 mm), such as 0.22 mm (or about 0.22 mm) or 0.24 mm (or about 0.24 mm). The thickness of the inner portion 211 can be in the range of 0.05 mm (or about 0.05 mm) to 0.30 mm (or about 0.30 mm), and is preferably 0.10 mm (or about 0.10 mm) or 0.16 mm (or about 0.16 mm).

[0160] Refer again Figure 2H The height (denoted as H-H) of the single longitudinal section bubble of the first elongated member 203 can be greater than the width (denoted as W-W) of the single longitudinal section bubble of the first elongated member 203. Since the greater height increases the size of the material voids in the outer wall of the bubble of the first elongated member 203, this configuration can improve the flexibility of the composite tube 201 by allowing for bending with a shorter radius. Therefore, some embodiments include the following implementation: the overall tube flexibility can be improved by providing a first elongated member 203 with a longitudinal section height greater than its longitudinal section width. It should be understood that while this example configuration may be preferred in some embodiments, other configurations and variations can be used in other embodiments as desired. For example, the height of the longitudinal section bubble of the first elongated member 203 can be less than its width.

[0161] In at least one embodiment, the height of the bubble (H-H) can be in the range of 1.2 mm (or about 1.2 mm) to 8.2 mm (or about 8.2 mm), such as 1.2 mm (or about 1.2 mm), 1.7 mm (or about 1.7 mm), 1.8 mm (or about 1.8 mm), 2.7 mm (or about 2.7 mm), 2.8 mm (or about 2.8 mm), 3 mm (or about 3 mm), 3.2 mm (or about 3.2 mm), 3.5 mm (or about 3.5 mm), 3.8 mm (or about 3.8 mm), 4 mm (or about 4 mm), 4.5 mm (or about 4.5 mm), 7.7 mm (or about 7.7 mm), or 8.2 mm (or about 8.2 mm). In at least one embodiment, the width of the bubble (W-W) can be in the range of 1.7 mm (or about 1.7 mm) to 8 mm (or about 8 mm), such as 1.7 mm (or about 1.7 mm), 3.2 mm (or about 3.2 mm), 3.5 mm (or about 3.5 mm), 4.0 mm (or about 4.0 mm), 4.2 mm (or about 4.2 mm), 5.2 mm (or about 5.2 mm), 5.5 mm (or about 5.5 mm), 6 mm (or about 6 mm), 7 mm (or about 7 mm), 7.5 mm (or about 7.5 mm), or 8 mm (or about 8 mm).

[0162] The relationship between bubble height (H-H) and bubble width (W-W) can be expressed as a ratio. A ratio of 0 to 1 exhibits the worst flexibility. Flexibility increases as this ratio increases. In at least one embodiment, the ratio of bubble height (H-H) to bubble width (W-W) can be in the range of 0.15 (or about 0.15) to 1.5 mm (or about 1.5), such as 0.16 (or about 0.16), 0.34 (or about 3.4), 0.50 (or about 0.50), 0.56 (or about 0.56), 0.57 (or about 0.57), 0.58 (or about 0.58), 0.67 (or about 0.67), 0.68 (or about 0.68), 0.73 (or about 0.73), 0.85 (or about 0.85), 1.1 (or about 1.1), and 1.3 (or about 1.3).

[0163] It is desirable for the outer profile of the bellows to be relatively smooth. As used in this specification, relative smoothness refers to the ridge between the first elongation member 203 and the second elongation member 205 along the length of the composite tube 201. A relatively smooth bellows has flatter, more closely spaced, or otherwise less prominent ridges. A relatively smooth profile can advantageously reduce noise generated when dragging the bellows across the edge of an object such as a table or countertop.

[0164] An example parameter used to quantify relative smoothness is the vertical difference between the outer radial apex 221 of the first elongation member 203 and the outer radial apex 223 of the second elongation member 205 of the composite tube 201 (e.g., in...). Figure 2H (As shown in the diagram). As the distance between the outer radial apex 221 and the outer radial apex 223 decreases, the composite tube 201 feels relatively smoother. In at least one embodiment, the vertical difference is in the range of 1 mm (or about 1 mm) to 4.6 mm (or about 4.6 mm), such as 1.0 mm (or about 1.0 mm), 1.1 mm (or about 1.1 mm), 1.3 mm (or about 1.3 mm), 1.4 mm (or about 1.4 mm), 1.6 mm (or about 1.6 mm), 1.9 mm (or about 1.9 mm), 2.0 mm (or about 2.0 mm), 2.3 mm (or about 2.3 mm), 2.4 mm (or about 2.4 mm), 3.0 mm (or about 3.0 mm), 3.3 mm (or about 3.3 mm), or 4.6 mm (or about 4.6 mm). The relative smoothness can also be quantified as the vertical distance between the outer radial apex 221 of the first elongation member 203 of the composite tube 201 and the outer radial nadir point 225 of the second elongation member 205. For example, this vertical distance could be 1.5 mm (or approximately 1.5 mm).

[0165] Another example parameter used to quantify relative smoothness is the ratio of the vertical difference between the radial vertex 221 of the first elongated member 203 of the composite tube 201 and a radial vertex 223 (or radial nadir point 225) of the second elongated member 205 to the maximum outer diameter of the composite tube 201 (that is, from the outer radial vertex 221 to the outer radial vertex 221 on the opposite side of the tube 201). As the maximum outer diameter increases, the vertical difference between the outer radial vertex 221 and the outer radial vertex 223 or nadir point 225 has a smaller effect on relative smoothness. In at least one embodiment, this ratio is in the range of 0.04 to 0.18, such as 0.04, 0.05, 0.07, 0.08, 0.09, 0.10, 0.11, 0.12, 0.16, 0.17, or 0.18 or around them.

[0166] As another example, the distance between corresponding points from one turn to the next (i.e., the pitch) can be selected to quantify relative smoothness. In some embodiments, the pitch can be in the range of 2.1 mm (or about 2.1 mm) to 9.5 mm (or about 9.5 mm), such as 2.1 mm (or about 2.1 mm), 3.8 mm (or about 3.8 mm), 4.8 mm (or about 4.8 mm), 5.1 mm (or about 5.1 mm), 5.5 mm (or about 5.5 mm), 5.8 mm (or about 5.8 mm), 6.4 mm (or about 6.4 mm), 7.5 mm (or about 7.5 mm), 8.1 mm (or about 8.1 mm), or 9.5 mm (or about 9.5 mm).

[0167] The ratio of the pitch of the composite tube 201 to the vertical difference between the radial apex 221 of the first elongation member 203 and the radial apex 223 of the second elongation member 205 of the composite tube 201 can be selected to quantify the relative smoothness. In some embodiments, this ratio is in the range of 1.3 (or about 1.3) to 4.8 (or about 4.8), such as 1.31 (or about 1.31), 1.76 (or about 1.76), 2.39 (or about 2.39), 2.42 (or about 2.42), 2.53 (or about 2.53), 2.71 (or about 2.71), 2.75 (or about 2.75), 3.26 (or about 3.26), 3.75 (or about 3.75), 4.13 (or about 4.13), 4.64 (or about 4.64), or 4.75 (or about 4.75).

[0168] The pitch-to-maximum outer diameter ratio can also be selected to improve relative smoothness. In some embodiments, the pitch-to-maximum outer diameter ratio of the tube can be in the range of 0.10 (or about 0.10) to 0.35 (or about 0.32), such as 0.11 (or about 0.11), 0.23 (or about 0.23), 0.28 (or about 0.28), 0.29 (or about 0.29), 0.30 (or about 0.30), 0.31 (or about 0.31), or 0.32 (or about 0.32).

[0169] As described above, the hollow portion of the first elongated member 203 can be filled with a fluid, namely a liquid or gas. The first elongated member 203 can be substantially sealed to prevent the loss of a certain amount of fluid. The first elongated member 203 can also be open at one or both ends to allow a continuous flow of liquid or gas.

[0170] The gas can be air because of its low thermal conductivity (2.62 x 10⁻⁶ K). -2(W / m·K) is desirable. It is also advantageous to use a gas with a higher viscosity than air, because the higher viscosity reduces heat transfer under natural convection conditions. Therefore, a gas such as argon (17.72 x 10⁻⁶ W / m·K at 300 K) is suitable. -3 W / m·K), Krypton (9.43 x 10⁻⁶ at 300K) -3 W / m·K) and xenon (5.65 x 10⁻⁶ at 300 K) -3 W / m·K) can increase insulation performance. Each of these gases is non-toxic, chemically inert, fire-retardant, and commercially available. The hollow portion of the first elongation member 203 can be sealed at both ends of the tube, causing the gas inside to essentially stagnate. Alternatively, the hollow portion can be a secondary pneumatic connection, such as a pressure sample line for delivering pressure feedback from the patient end of the tube to the controller.

[0171] Examples of liquids can include water or other biocompatible liquids with high heat capacity. For example, nanofluids can be used. One example of a nanofluid with suitable heat capacity includes water and substances such as aluminum nanoparticles.

[0172] In use, the fluid in the hollow portion of the first elongated member 203 can be configured to measure one or more properties of the gas within the tube 201, the first elongated member 203, the second elongated member 205, and / or the lumen 207 of the tube 201. In at least one embodiment, the pressure of the gas moving along the lumen of the tube (“lumen gas”) can be measured. A reference measurement of the pressure of the fluid in the hollow portion of the first elongated member 203 (“hollow fluid”) is performed before the lumen gas begins to circulate. As the lumen gas begins to pass through the tube 201, the pressure of the lumen gas tends to cause a proportional increase in the pressure of the hollow fluid within the first elongated member 203. The pressure of the lumen gas within the tube 201 can be determined by comparing the measurement obtained in use with the reference measurement. In another embodiment, a hollow fluid is selected that modifies one or more properties based on the operating thermal range of the lumen gas within the tube 201. In this way, the temperature of the lumen gas can be determined by measuring the properties of the hollow fluid. For example, a hollow fluid that expands with temperature can be used. During use, the temperature of this hollow fluid tends to match the temperature of the gas flow within the cavity. The temperature of the gas within the cavity can then be determined by measuring the pressure of the hollow fluid. This can have specific advantages when the temperature of the gas flow within the cavity is difficult or undesirable to measure directly.

[0173] In at least one embodiment, the extrudate used to form the first elongated member 203 further comprises a mineral filler. The extrusion method will be described in more detail below. Talc or hydrated magnesium silicate is a suitable mineral filler. In addition to talc, other suitable mineral fillers include calcium carbonate, calcium magnesium carbonate such as dolomite, barium sulfate, calcium silicate, kaolin, and mica, each of which may be added alone or in combination. Suitable mineral fillers may also have a particle size of less than 10 μm (or about 10 mm) or less than 2.5 μm (or about 2.5 mm).

[0174] It has been found that adding mineral filler to a plastic extruder reduces the tackiness of the resulting first elongated member 203. Tackiness refers to the perceptible adhesiveness or stickiness of the material of the first elongated member 203. A stickier material feels more sticky than a less sticky material. A stickier material also tends to stick to less desirable substances, such as dirt or hair, compared to a less sticky material. When bundled (and unbundled) around the perimeter of an elbow, adding mineral filler has been found to reduce noise generated during pipe movement, bending, etc., by reducing the degree to which adjacent bubbles stick to each other (and do not stick).

[0175] It was also found that adding mineral fillers to the extrudate further reduces noise generated when dragging the first elongated member 203 along the edge of an object such as a table or bedside table. The mineral fillers help reflect sound into the surrounding polymer, preventing it from traveling straight through. This improved sound reflection also gives the polymer phase more opportunities to absorb sound energy, thus providing inherent noise reduction. The mineral fillers also reduce the stiffness of the plastic extrudate, thereby improving its noise-reducing properties.

[0176] In some embodiments, the mineral filler comprises 1.5 to 10 (or about 1.5 to about 10) by weight of the total extrudate. In some embodiments, the mineral filler comprises 1.5 to 5 (or about 1.5 to about 5) by weight of the total extrudate. In some embodiments, the mineral filler comprises 10 (or about 10) or less by weight of the total extrudate. In some embodiments, the mineral filler comprises 5 (or about 5) or less by weight of the total extrudate. In some embodiments, the mineral filler comprises 1.5 (or about 1.5) or more by weight of the total extrudate.

[0177] exist Figure 2F In this embodiment, the first elongated member 203 forms a plurality of hollow bubble-like structures in its longitudinal section. In this example, there are multiple bubble-like structures, and more specifically, between two adjacent sleeves of the first elongated member 203 between the sleeves of the second elongated member 205. Figure 2GThis construction is shown in more detail elsewhere in this disclosure. As described and shown elsewhere in this disclosure, certain constructions can achieve having more than two, for example three, of the first elongation member 203's sleeves between the sleeves of the second elongation member 205.

[0178] Embodiments in which multiple adjacent sheaths of the first elongated member 203 are included between the sheaths of the second elongated member 205 can be advantageous because they improve overall tube flexibility. As described below, the flexibility of the substantially solid second elongated member 205 is generally less than that of the hollow first elongated member 203. Therefore, some embodiments include the following implementation: overall tube flexibility can be improved by increasing the number of bubbles in the first elongated member 203 between the sheaths of the second elongated member 205.

[0179] Another advantage of embodiments in which multiple adjacent sheaths of the first elongation member 203 are included between the sheaths of the second elongation member 205 is improved recovery from compression. It has been observed that samples with multiple bubbles between the sheaths of the first elongation member 203 recover their shape more quickly after compression compared to samples with a single bubble between the sheaths of the first elongation member 203.

[0180] Another advantage of embodiments in which multiple adjacent sheaths of the first elongation member 203 are included between the sheaths of the second elongation member 205 is improved crush resistance. Crush resistance is a mechanical property that plays an important role in the resilience of the tube in operation. Hospital environments can be harsh, as the tube can be crushed by a patient's arm or leg, bed frames, and other equipment. Example crush resistance properties will be discussed in more detail below.

[0181] Another advantage of the multi-bubble structure is that it provides the ability to hold or transport additional fluids. As explained above, the hollow portion of the first elongated member 203 can be filled with a gas. Multiple discrete bubbles or hollow portions can be filled with multiple discrete gases. For example, one hollow portion can hold or transport a first gas, and a second hollow portion can be used as a secondary pneumatic connection, such as a pressure sample line for delivering pressure feedback from the patient end of the tube to a controller. As another example, multiple discrete bubbles or hollow portions can be filled with a combination of liquids or a combination of liquids and gases. For example, a first bubble can hold or transport a gas, and a second bubble can hold or transport a liquid. Suitable liquids and gases have been described above.

[0182] It should be understood that, although in Figure 2F and 2G The configuration may be preferred in some embodiments, but other configurations may be used in other embodiments as may be desired.

[0183] Second elongation member

[0184] Refer again Figure 2A and Figure 2B The second elongated member 205 is also helically wound and is engaged with the first elongated member 203 between multiple turns of the first elongated member 203. The second elongated member 205 can form at least a portion of the lumen 207 of the elongated tube. The second elongated member 205 acts as a structural support for the first elongated member 203.

[0185] The weight of a CPAP machine is typically in the range of 2 to 4 kg (or about 2 to 4 kg). Therefore, the breaking strength of the composite tube 201 (the horizontal tensile load or force required to separate the first elongation member 203 from the second elongation member 205) is desirablely high enough to prevent separation in the event that a user attempts to use the composite tube 201 to lift a CPAP machine connected to it. Therefore, the breaking strength is preferably greater than 20 N (or about 20 N), and more preferably greater than 30 N (or about 30 N). In some embodiments, the breaking strength is in the range of 75 to 80 N (or about 75 to 80 N). The yield strength (the maximum stress that can be generated without causing plastic deformation) can be in the range of 55 to 65 N (or about 55 to 65 N). In some embodiments, the composite tube 201 will not stretch (horizontally deflect) more than 0.5 mm (or about 0.5 mm) when a lateral force of 2 N is applied.

[0186] In at least one embodiment, the second elongated member 205 is wider at its base (proximal to the lumen 207) and narrower at its top. For example, the shape of the second elongated member is generally triangular, generally T-shaped, or generally Y-shaped. However, any shape conforming to the contour of the corresponding first elongated member 203 is suitable.

[0187] Preferably, the second elongated member 205 is flexible to facilitate bending of the tube. Desiredly, the second elongated member 205 has lower flexibility than the first elongated member 203. This improves the ability of the second elongated member 205 to provide structural support for the first elongated member 203. For example, the modulus of the second elongated member 205 is preferably 30-50 MPa (or approximately 30-50 MPa). The modulus of the first elongated member 203 is less than the modulus of the second elongated member 205. The second elongated member 205 can be solid, or primarily solid.

[0188] Figure 6A The longitudinal section of the composite pipe 201 in a neutral position is shown. Figure 6AConcentrated in one turn or one bubble of the first elongated member 203 and two turns of the second elongated member 205. The first elongated member 203 and the second elongated member 205 have a radially outermost connection point 601. In this example, the inner portion 211 of the first elongated member 203 is thinner than the outer portion 219 of the first elongated member 203. In this example, the second elongated member 205 also has a triangular cross-section. The lumen 207 is located below the base of the first elongated member 203 and the second elongated member 205. Figure 6B It shows the bent position. Figure 6A The composite tube 201, wherein the composite tube 201 has been bent into a ∩ shape (e.g. Figure 6C (as shown in the image). Figure 6B The focus is again on one turn or one bubble of the first elongation member 203 and two turns of the second elongation member 205. More specifically, Figure 6B The coil or bubble-like structure is concentrated at the top of the ∩ shape, i.e., at the point of maximum bending. The radius of curvature of the composite tube 201 is limited by the length of the segment between the adjacent outermost connection points 601 in the outer portion 219. If the composite tube 201 bends beyond the minimum radius of curvature, the outer wall forms as... Figure 6D The recess 605 shown in the figure.

[0189] Various polymers and plastics, including medical-grade plastics, are suitable for the body of the second elongation member 205. Examples of suitable materials include: polyolefin elastomers, polyetheramide blocks, thermoplastic copolyester elastomers, EPDM-polypropylene blends, and thermoplastic polyurethanes. In some embodiments, the first elongation member 203 and the second elongation member 205 may be made of the same material. The second elongation member 205 may also be made of a material of a different color than the first elongation member 203 and may be transparent, translucent, or opaque. For example, in one embodiment, the first elongation member 203 may be made of a transparent plastic, and the second elongation member 205 may be made of an opaque blue, black, or other colored plastic.

[0190] The flexible hollow body and the integrally supported helical winding structure provide resistance to compression while giving the tube wall sufficient flexibility to allow for small-radius bending without buckling, closure, or collapse. Preferably, the tube can be bent around a metal column with a diameter of 25 mm without buckling, closure, or collapse, as defined in experiments using bending to increase flow resistance according to ISO 5367:2000(E).

[0191] This structure also provides a smooth lumen surface 207, which helps prevent deposits and improves gas flow. It has been found that this hollow body improves the insulation properties of the tube while allowing it to remain lightweight.

[0192] In some embodiments, the second elongated member 205 may be made of a water-absorbing material. For example, a water-absorbing sponge-like material may be used. In such embodiments, the second elongated member 205 may be attached to a water source, such as a water bag. In use, water is delivered along at least a portion (preferably substantially the entire length) of the second elongated member 205. As gas flows through the second elongated member 205, water vapor will tend to be absorbed by the gas within the lumen 207, thereby humidifying the gas flow.

[0193] In some embodiments, one or more heating filaments 215 (such as those embedded in the second elongated member 205) are used. Figure 2B (As shown) can be controlled to change the evaporation rate, and thus change the level of humidification supplied to the gas stream. Although Figure 2B The heating filament 215 is specifically shown, but it should be understood that the second elongated member 205 may encapsulate or contain one or more other conductive materials, such as one or more filaments, and specifically a sensor (not shown). Such conductive materials may be disposed within the second elongated member 205 for heating or sensing the gas flow. The heating filament 215 can minimize the cold surface of condensates that may form from humid air. The heating filament 215 can also be used to alter the temperature profile of the gas within the lumen 207 of the composite tube 201.

[0194] exist Figure 2B In this example, two heating filaments 215 are encapsulated within a second elongated member 205, one on each side of the vertical portion of the "T". The heating filaments 215 comprise an alloy or conductive polymer of a conductive material such as aluminum (Al) and / or copper (Cu). Preferably, when the heating filaments 215 reach their operating temperature, the material forming the second elongated member 205 is selected such that it does not react with the metal in the heating filaments 215. These filaments 215 may be spaced apart from the lumen 207 so that they are not exposed within the lumen 207. At one end of the composite tube, the paired filaments may be formed as a connecting loop.

[0195] In at least one embodiment, multiple filaments are disposed in the second elongation member 205. These filaments can be electrically connected together to share a common track. For example, a first filament, such as a heating filament, can be disposed on a first side of the second elongation member 205. A second filament, such as a sensing filament, can be disposed on a second side of the second elongation member 205. A third filament, such as a grounding filament, can be disposed between the first and second filaments. The first, second, and / or third filaments can be connected together at one end of the second elongation member 205.

[0196] Figure 2E A longitudinal section of the top portion of another composite pipe is shown. Figure 2EWith Figure 2B Same orientation. In Figure 2E In the example, the heating filament 215 is... Figure 2B The filaments 215 are spaced further apart from each other. It has been found that increasing the space between the heating filaments can improve heating efficiency, and some embodiments include this implementation. Heating efficiency refers to the ratio of the amount of heat input into the tube to the amount of energy output from or recoverable from the tube. Generally, the greater the energy (or heat) dissipated from the tube to the ambient atmosphere, the lower the heating efficiency. To improve heating performance, the heating filaments 215 can be spaced equally (or substantially equally) along the tube opening. Alternatively, the filaments 215 can be positioned at the end of the second elongated member 205, which provides simpler manufacturing.

[0197] Next reference Figures 7A to 7G These figures show an example construction of the second elongation member 205. Figure 7A A cross-section of the second elongated member 205 is shown, the shape of which is similar to... Figure 2B Similar to the T-shape shown. In this example embodiment, the second elongated member 205 does not have a heating filament. Other shapes of the second elongated member 205 can also be utilized, including variations of the T-shape as described below, as well as a triangular shape.

[0198] Figure 7B Another example of a second elongated member 205 is shown, which has a T-shaped cross-section. In this example, heating filaments 215 are embedded within a cut 701 on either side of the vertical portion of the "T" in the second elongated member 205. In some embodiments, the cut 701 may be formed in the second elongated member 205 during extrusion. Alternatively, the cut 701 may be formed in the second elongated member 205 after extrusion. For example, a cutting tool may form the cut in the second elongated member 205. Preferably, these cuts are formed by the heating filaments when they are pressed or pulled (mechanically secured) into the second elongated member 205 shortly after extrusion, while the second elongated member 205 is relatively soft. Alternatively, one or more heating filaments may be mounted (e.g., attached, bonded, or partially embedded) on the base of the elongated member, such that the filaments are exposed within the lumen of the tube. In such embodiments, it may be desirable for the filaments to be insulated, thereby reducing the risk of fire when flammable gases such as oxidizers pass through the lumen.

[0199] Figure 7C Another example, the second elongated member 205, is shown in cross-section. The second elongated member 205 has a generally triangular shape. In this example, the heating filament 215 is embedded on opposite sides of the triangle.

[0200] Figure 7D Another example of a second elongated member 205 is shown in cross-section. The second elongated member 205 includes four grooves 703. The grooves 703 are indentations or grooves on their cross-sectional profile. In some embodiments, the grooves 703 may facilitate the formation of cuts (not shown) for embedding filaments (not shown). In some embodiments, the grooves 703 facilitate the positioning of filaments (not shown) that are pressed or pulled into these grooves and thereby embedded in the second elongated member 205. In this example, the four activation grooves 703 facilitate the placement of up to four filaments, such as four heating filaments, four sensing filaments, two heating filaments and two sensing filaments, three heating filaments and one sensing filament, or one heating filament and three sensing filaments. In some embodiments, the heating filaments may be located on the outer side of the second elongated member 205. The sensing filaments may be located on the inner side.

[0201] Figure 7E Another example, a second elongated member 205, is shown in cross-section. The second elongated member 205 has a T-shaped profile and multiple grooves 303 for placing heating filaments.

[0202] Figure 7F Another example of a second elongated member 205 is shown in cross-section. Four heating filaments 215 are encapsulated within the second elongated member 205, two on each side of the vertical portion of the “T”. As explained in more detail below, these filaments are encapsulated within the second elongated member 205 because the second elongated member 205 is extruded around these filaments. No cuts are formed to embed the heating filaments 215. In this example, the second elongated member 205 also includes multiple grooves 703. Because the heating filaments 215 are encapsulated within the second elongated member 205, the grooves 703 are not used to help form cuts for embedding the heating filaments. In this example, the grooves 703 can help separate the embedded heating filaments, making it easier to peel off the individual cores, for example, when terminating the heating filaments.

[0203] Figure 7G Another example of a second elongated member 205 is shown in cross-section. The second elongated member 205 has a generally triangular shape. In this example, the shape of the second elongated member 205 is similar to... Figure 7C The shapes are similar, but four filaments 215 are encapsulated in the second elongation member 205, all of which are located at the center of the bottom third of the second elongation member 205 and are arranged along a generally horizontal axis.

[0204] As explained above, it may be desirable to increase the distance between the filaments to improve heating efficiency. In some embodiments, however, when the heating filament 215 is incorporated into the composite tube 201, the filament 215 can be positioned relative to the center of the second elongation member 205. This central positioning improves the stability of the reusable composite tube, partly because such positioning reduces the likelihood of filament breakage during repeated bending of the composite tube 201. The centrally positioned filament 215 also reduces the risk of fire because it is covered with multiple layers of insulation and can be removed from the gas line.

[0205] As explained above, some examples illustrate the proper placement of filament 215 in the second elongation member 205. In the aforementioned examples, which include more than one filament 215, the filaments 215 are generally aligned along a horizontal axis. Alternative configurations also apply. For example, two filaments may be aligned along a vertical axis or along a diagonal axis. Four filaments may be aligned along a vertical axis or along a diagonal axis. Four filaments may be arranged in a cross-shaped configuration, with one filament positioned at the top of the second elongation member, one filament positioned at the bottom of the second elongation member (adjacent to the lumen of the tube), and two filaments positioned on opposing arms on a T-shaped, Y-shaped, or triangular base.

[0206] size

[0207] Tables 3 and 4 show some example dimensions of the medical tubing described herein, as well as some ranges for these dimensions. These dimensions refer to the transverse cross-section of the tubing. In these tables, the lumen diameter represents the inner diameter of the tubing. The pitch represents the distance measured axially along the tubing between two overlapping points, that is, the distance between the tips of the adjacent vertical portions of the "T" shape of the second elongation member. The bubble width represents the width of a bubble (maximum outer diameter). The bubble height represents the height of a bubble from the lumen of the tubing. The bead height represents the maximum height of the second elongation member from the lumen of the tubing (e.g., the height of the vertical portion of the "T" shape). The bead width represents the maximum width of the second elongation member (e.g., the width of the horizontal portion of the "T" shape). The bubble thickness represents the thickness of the bubble wall.

[0208] Table 3

[0209]

[0210] Table 4

[0211]

[0212] In another example embodiment, the medical tube has approximate dimensions as shown in Table 5.

[0213] Table 5

[0214]

[0215]

[0216] In another example embodiment, the medical tube has approximate dimensions as shown in Table 6.

[0217] Table 6

[0218]

[0219] Preferably, the lower limits of the ranges in Table 6 correspond to each other, and the upper limits of the ranges in Table 6 correspond to each other.

[0220] The examples in Tables 5 and 6 may be particularly advantageous for applications involving obstructive sleep apnea.

[0221] Tables 7, 8, and 9 provide example ratios between the tube size characteristics described in Tables 3, 4, and 6, respectively.

[0222] Table 7

[0223]

[0224]

[0225] Table 8

[0226] ratio baby aldult Lumen diameter: pitch 2.3:1 2.4:1 Pitch: width of the bubble 1.1:1 1.1:1 Pitch: Bead width 2.2:1 2.2:1 Bubble width: Bead width 2.0:1 2.1:1 Lumen diameter: Bubble height 3.9:1 4.5:1 Lumen diameter: Bead height 12.2:1 10.6:1 Bubble height: Bead height 3.1:1 2.4:1 Lumen diameter: Bubble thickness 27.5:1 90.0:1

[0227] Table 9

[0228] ratio value Lumen diameter: pitch 3.4:1 Pitch: width of the bubble 0.93:1 Pitch: Bead width 2.2:1 Bubble width: Bead width 1.7:1 Lumen diameter: Bubble height 5.4:1 Lumen diameter: Bead height 10.8:1 Bubble height: Bead height 1.7:1 Lumen diameter: The thickness of the bubble furthest from the lumen at the top. 71.7:1 Lumen diameter: Thickness of the bubble-like structure adjacent to the lumen 172:1

[0229] Variable pitch and / or variable diameter

[0230] The foregoing description discloses different constructions with constant pitch and constant diameter. However, some embodiments may combine variable pitch and / or variable diameter.

[0231] Variable pitch is desirable because it allows for better variation in the amount of heat delivered to the airflow along the length of the tube. The ability to control where heat is delivered within the tube can be used to control or reduce raining effects within the tube. For example, a tube-end temperature setpoint can be achieved for given conditions where raining effects within the tube are insufficient to prevent them, particularly at or near the inlet where the gas temperature in the tube may be close to the dew point temperature (high relative humidity). Some embodiments include the following implementation: redistributing the heat source to concentrate it near the inlet of the tube can help ensure a greater axial concentration of heat Q(z) [W / m] in this region, where z is the axial placement of the heat source in the tube starting at the end of the device.

[0232] Figure 8A An example composite tube 201 with variable pitch is shown. In this example, tube 201 has a smaller pitch near the device end 801. Therefore, the heating filaments 215 in this region are more densely spaced, resulting in more heating and greater, more precise temperature control at that portion of tube 201. Tube 201 has a larger pitch at the patient end 803. The greater spacing between the heating filaments 215 allows the gas to cool down as it approaches the patient. This prevents the patient from receiving excessively hot gas and reduces the formation of a rain effect. Figure 8B It shows Figure 8A The temperature profile of the composite tube is shown. Other temperature profiles are also possible and can be customized to achieve specific desired effects.

[0233] The geometry of tube 201 also affects its mechanical properties. Increasing the size of the bubble in the first elongation member improves the flexibility of tube 201. Conversely, a smaller bubble size creates more rigid areas in tube 201. By altering flexibility and rigidity, the mechanical properties of tube 201 can be customized. Changing the diameter of tube 201, a smaller diameter near the patient interface can be achieved, increasing patient comfort, improving aesthetics, and reducing interface damage.

[0234] Other characteristics

[0235] Tables 10–13 show some example characteristics of a composite tube (labeled “A”), as described herein, which has a heating filament incorporated into the inner side of the second elongation member. For comparison, characteristics of the Fisher & Paykel Model RT100 disposable bellows (labeled “B”) are also presented, which has a heating filament spirally wound inside the tube’s bore.

[0236] The resistance to flow ratio (RTF) was measured according to Annex A of ISO 5367:2000(E). The results are summarized in Table 10. As can be seen below, the RTF of this composite pipe is lower than that of the RT100 pipe.

[0237] Table 10

[0238]

[0239] The condensate or "rain-washed material" in the tube refers to the weight of condensate collected daily at a gas flow rate of 20 L / min and at room temperature of 18°C. Humidified air was continuously flowed through the tube from the chamber. The tube weight was recorded each day before and after the test. Three consecutive tests were performed, with the tube dried between tests. The results are shown in Table 11 below. The results show that the rain-washing effect in this composite tube is significantly lower than that in the RT100 model tube.

[0240] Table 11

[0241]

[0242] Power requirement refers to the power consumed during the condensation test. In this test, ambient air was maintained at 18°C. Humidification chamber (see, for example, in...) Figure 1 The humidification chamber 129 is powered by an MR850 heating base. The heating filament within the tube is independently powered by a DC power supply. Different flow rates are set, and the temperature of the chamber is maintained at 37°C at the chamber output. Then, the DC voltage of the circuit is changed to generate a temperature of 40°C at the circuit output. The voltage required to maintain this output temperature is recorded, and the resulting power is calculated. The results are shown in Table 12. The results show that composite tube A uses significantly more power than tube B. This is because tube B uses a spiral heating filament in the orifice to heat the gas from 37°C to 40°C. This composite tube does not heat the gas rapidly because the heating filament is located within the tube wall (embedded in the second elongated member). Instead, the composite tube is designed to maintain the gas temperature and prevent rain washing by maintaining the orifice temperature above the dew point of the humidified gas.

[0243] Table 12

[0244] Flow rate (L / min) 40 30 20 Power required (W) for tube A 46.8 38.5 37.8 Power required (W) for tube B. 28.0 27.5 26.8

[0245] Vertical deflection can be used to quantify the flexibility of composite tubes. For example, a three-point bending test can be used to test vertical deflection. A first 300mm sample of tube A and a second 300mm sample of tube B are tested separately on a flexible fixture. Figure 9A The diagram shows a top-view cross-sectional view of the elastic clamp. The clamp 901 uses a 25-mm rod 903 with a fixed mass of 120g to apply force to each tube 201. This rod is positioned between two rollers 905 and 907. These rollers are spaced 150mm apart. The force applied by the rod 903 is approximately 1.2N (0.12kg × 9.81m / s²). 2 ). Figure 9B The diagram shows a detailed front top cross-sectional view of rollers 905 and 907. Both rollers 905 and 907 have... Figure 9B The same dimensions are shown. The Instron 5560 testing system instrument was used to measure load and elongation. Each tube sample was tested three times; the elongation of the tube under the applied load was measured to obtain its respective average stiffness constant. The average stiffness constants of tubes A and B are reproduced in Table 13.

[0246] Table 13

[0247] Tube Stiffness (N / mm) A 0.028 B 0.088

[0248] The weight of the tube can be very important, especially for CPAP applications. Patients are more comfortable during sleep if they experience less weight near their face. A lighter composite tube 201 will not pull the patient's head in a particular direction as a heavier tube would. To ensure patient comfort, the total mass or weight in the area near the patient end of the composite tube 201 may be specified to be less than a designated value. In some embodiments, the mass of the tube closest to the patient end (300 mm) is less than 24 g (or about 24 g). Desiredly, the mass of the tube closest to the patient end (300 mm) is less than 16 g (or about 16 g). In some embodiments, the mass of the tube closest to the patient end (300 mm) is less than 15 g (or about 15 g). The total mass of the composite tube may also be specified to be less than a designated value. In some embodiments, the tube mass is less than 130 g (or about 130 g). Desiredly, the tube mass is less than 120 g (or about 120 g). In some embodiments, the tube mass is less than 100 g (or about 100 g).

[0249] The following discusses additional characteristics relating to a composite tube 201 having two bubbles between the sheath of the second elongation member 205 as described above.

[0250] A first sample tube, 300 mm long and comprising two bubbles within the sheath of the second elongation member 205, and a second sample tube, 300 mm long and comprising one bubble within the sheath of the second elongation member 205, were each tested on the elastic clamp 901 described above. This vertical deflection was measured using positioning with a fixed weight relative to the vertical support 909 of the elastic clamp, see [reference needed]. Figures 9C to 9F The photo.

[0251] Figure 9C A front perspective view of the second sample under test in fixture 901 is shown. Figure 9D A rear perspective view of the second sample under test in fixture 901 is shown. Figure 9E A front perspective view of the first sample under test in fixture 901 is shown. Figure 9F A rear perspective view of the first sample under test, located in fixture 901, is shown. Figures 9C to 9F As shown, Figure 9E and Figure 9F The vertical deflection of the second sample shown is substantially greater than that in Figure 9C and Figure 9D The first sample is shown in the image. Specifically, the second sample has a vertical deflection of 3 mm, while the first sample is much more flexible, with a vertical deflection of 42 mm.

[0252] Use an Instron instrument, such as Figure 10AThe photograph shown depicts the assembly undergoing a compression resistance test on four tube samples. The cylinder 1001 was inserted downwards 16 mm from the top of the tube at a rate of 60 mm / min. The Instron instrument has a load sensor to accurately measure the ratio of force applied to the component to elongation. This load-to-elongation ratio is plotted, as shown in... Figure 10B As shown in the image.

[0253] By matching the best line with Figure 10B The data were fitted and their gradients were calculated to obtain the compression stiffness of each sample. Table 14A shows the calculated compression stiffness of each sample. In Table 14A (and elsewhere in this disclosure), the term "double bubble" refers to a tubular sample comprising two bubbles between the sheaths of the second elongation member 205 when the sample is viewed in a longitudinal section. The term "single bubble" refers to a tubular sample comprising a single bubble between the sheaths of the second elongation member 205 when the sample is viewed in a longitudinal section. The average compression stiffness (measured in N / mm) represents the average maximum force per unit width without compression.

[0254] Table 14A

[0255]

[0256]

[0257] As shown in the table above, the single-bubble tube has an average crushing stiffness of 3.86 N / mm, while the double-bubble tube has an average crushing stiffness of 3.21 N / mm. In other words, the double-bubble tube has approximately 16.8% lower crushing resistance than the single-bubble tube. However, it has been observed that the crushing stiffness per unit thickness of the double-bubble tube is approximately 165% of the value of the single-bubble tube, as shown in Table 14B below.

[0258] Table 14B

[0259]

[0260] In other words, when considering the outer bubble thickness, the double-bubble variant exhibits approximately 65% ​​greater resistance to compression and extrusion than the single-bubble variant. Figure 2F and Figure 2G Similar to the bubbles shown, the height of the tested bubbles in the double-bubble structure is greater than their width, resulting in more material in their vertical plane. Therefore, it is believed that this unexpected improvement in the compressibility per unit thickness of the bubbles can be attributed to the additional vertical mesh between the beads acting in the compressive direction.

[0261] Tensile tests were also performed on single-bubble and double-bubble samples. Both samples were 230 mm in length and elongated by 15 mm at a rate of 10 mm / min. The force required to elongate the samples was measured. The results are shown in Table 14C.

[0262] Table 14C

[0263] sample Peak force (N) at a 15mm extension Double bubble 17.60 single bubble 54.65

[0264] As shown in Table 14C, the double-bubble tube is significantly easier to extend in the axial (longitudinal) plane. It is believed that this increase in longitudinal extension is due to the greater amount of material between the beads in the single-bubble tube acting in the axial plane.

[0265] thermal properties

[0266] In an embodiment where a composite tube 201 incorporates a heating filament 215, heat can be lost through the wall of the first elongated member 203, resulting in uneven heating. As explained above, one way to compensate for these heat losses is to apply an external heat source to the wall of the first elongated member 203, which helps regulate the temperature and combat heat loss. However, other methods for optimizing thermal properties can also be used.

[0267] Refer again Figures 5A to 5C These figures illustrate example configurations of the bubble height (i.e., measurements of the cross-sectional height of the first elongated member 203 from the surface facing the inner lumen to the surface forming the maximum outer diameter) to improve thermal properties.

[0268] The size of the bubble can be selected to reduce heat loss in the composite tube 201. Generally, increasing the height of the bubble increases the effective thermal resistance of the tube 201 because a larger bubble height allows the first elongated member 203 to hold more insulating air. However, it has been found that at a certain bubble height, changes in air density cause convection within the tube 201, thereby increasing heat loss. Furthermore, at a certain bubble height, the surface area becomes very large, so that heat loss through the surface outweighs the benefits of the increased bubble height. Some embodiments include these implementations.

[0269] The radius of curvature and curvature of a bubble can be used to determine the desired bubble height. The curvature of an object is defined as the reciprocal of its radius of curvature. Therefore, the larger the radius of curvature of an object, the smaller its curvature. For example, the radius of curvature of a flat surface is ∞, and therefore its curvature is 0.

[0270] Figure 5A The longitudinal section of the top portion of the composite pipe is shown. Figure 5AAn embodiment of the composite tube 201 is shown, in which the bubble has a large height. In this example, the bubble has a relatively small radius of curvature and therefore a large curvature. Furthermore, the height of the bubble is approximately three to four times greater than the height of the second elongated member 205.

[0271] Figure 5B A longitudinal section of the top portion of another composite pipe is shown. Figure 5B An embodiment of the composite tube 201 is shown, in which the top of the bubble is flat. In this example, the bubble has a very large radius of curvature but a small curvature. Furthermore, the height of the bubble is approximately the same as the height of the second elongated member 205.

[0272] Figure 5C A longitudinal section of the top portion of another composite pipe is shown. Figure 5C An embodiment of the composite tube 201 is shown, in which the width of the bubble is greater than the height of the bubble. In this example, the radius of curvature and curvature of the bubble are... Figure 5A and Figure 5B Between, and the center of the radius of the upper part of the bubble is on the outer side of the bubble (with Figure 5A (In comparison). The turning points on the left and right sides of the bubble are approximately in the middle of the bubble (in terms of height) (opposite to the lower part of the bubble, such as...). Figure 5A (As shown in the diagram). Furthermore, the height of the bubble is approximately twice the height of the second elongated member 205, thus making the height of the bubble... Figure 5A and 5B The heights shown are between.

[0273] Figure 5A The design minimizes heat loss in the tube. Figure 5B The structure of the tube results in the highest heat loss. Figure 5C The heat loss of the structure is Figure 5A and Figure 5B Between the structures. However, in Figure 5A The large outer surface area and convective heat transfer in the structure lead to inefficient heating. Therefore, in Figure 5A In the arrangement of the three types of bubbles in -5C, determine Figure 5C It possesses optimal overall thermal characteristics. The practical implication of this thermal efficiency is that when the same amount of heat energy is input into these three tubes, Figure 5C The structure of the tube results in the greatest temperature rise along its length. Figure 5C The bubbles are large enough to increase the amount of insulating air, but not large enough to cause significant convective heat loss. Figure 5B Its structure has the worst thermal properties, that is... Figure 5B The design minimizes the temperature rise along the length of the tube. Figure 5AIts structure has intermediate thermal properties, and causes its temperature rise to be higher than that of other materials. Figure 5C The structure is low.

[0274] It should be understood that, although Figure 5C The configuration may be preferred in some embodiments, but other configurations, including those that may be desired, are also possible. Figure 5A , Figure 5B The constructions shown in other variations can be used in other embodiments.

[0275] Table 15 shows Figure 5A , Figure 5B and Figure 5C The height of the bubble, the outer diameter of the tube, and the radius of curvature of these structures are shown in the figures.

[0276] Table 15

[0277] Pipe (pictured) 5A 5B 5C Height of the bubble (mm) 3.5 5.25 1.75 Outer diameter (mm) 21.5 23.25 19.75 Radius of curvature (mm) 5.4 3.3 24.3

[0278] Table 16A shows, for example Figure 11A , Figure 11B and Figure 11C The height, outer diameter, and radius of curvature of the bubble shown are illustrated.

[0279] Table 8A

[0280] Pipe (pictured) 10A 10B 10C Height of the bubble (mm) 6.6 8.4 9.3 Outer diameter (mm) 24.6 26.4 27.3 Radius of curvature (mm) 10 8.7 5.7

[0281] It should be noted that, generally speaking, the smaller the radius of curvature, the tighter the bend around the tube can be without causing the bubble to collapse or "bend." For example, Figure 11D The image shows a pipe that is bent beyond its radius of curvature (specifically, it shows...). Figure 11A The tube is bent with a radius of curvature of approximately 5.7 mm, causing the bubble walls to fold. Folding is generally undesirable because it detracts from the tube's appearance and impairs its thermal properties.

[0282] Therefore, in some applications, constructions with increased bending properties (such as...) Figure 5A or Figure 5B Those shown may be desirable, regardless of their lower thermal efficiency. In some applications, a tube with an outer diameter of 25 mm to 26 mm (or about 25 mm to about 25 mm) has been found to provide satisfactory performance. It should be understood that, although in Figure 5A Hehe Figure 5B The configuration may be preferred in some embodiments, but other configurations, including those that may be desired, are also acceptable. Figure 11A The constructions shown in –11D and other variants can be used in other embodiments.

[0283] Refer again Figures 5C to 5F These figures illustrate an example positioning of heating element 215, which has a similar bubble shape to improve thermal properties. The positioning of heating element 215 can alter the thermal properties within composite tube 201.

[0284] Figure 5C A longitudinal section of the top portion of another composite pipe is shown. Figure 5C An embodiment of the composite tube 201 is shown, wherein the heating element 215 is positioned at the center of the second elongated member 205. This example shows the heating elements 215 positioned close to each other but not close to the bubble wall.

[0285] Figure 5D A longitudinal section of the top portion of another composite pipe is shown. Figure 5D An embodiment of the composite tube 201 is shown, wherein... Figure 5C In comparison, the heating elements 215 are the furthest apart in the second elongated member 205. These heating elements are closer to the bubble wall and provide better thermal regulation within the composite tube 201.

[0286] Figure 5E A longitudinal section of the top portion of another composite pipe is shown. Figure 5E An embodiment of the composite tube 201 is shown, wherein the tips of the heating elements 215 are spaced apart from each other on the vertical axis of the second elongated member 205. In this example, the heating elements 215 are equidistant from each bubble wall.

[0287] Figure 5F A longitudinal section of the top portion of another composite pipe is shown. Figure 5F An embodiment of the composite tube 201 is shown, wherein the heating elements 215 are spaced apart at opposite ends of the second elongated member 205. The heating elements 215 are located close to the bubble wall, particularly with... Figure 5C -5E in comparison.

[0288] exist Figure 5C Of the four filament arrangements shown in –5F, determine Figure 5F They possess optimal thermal properties. Because they have similar bubble shapes, the heat loss of tubes with all configurations is similar. However, when the same amount of heat energy is input into the tube, Figure 5F The fine filament construction results in the greatest temperature rise along the length of the tube relative to the temperature of the large volume of gas inside. Figure 5D Its structure has the second-best thermal properties, and makes the temperature rise along the length of the tube the second largest. Figure 5C Its structural performance is the third best. Figure 5E Its construction results in the worst performance and minimizes the temperature rise along the length of the tube when the same amount of heat is input.

[0289] It should be understood that, although Figure 5F The configuration may be preferred in some embodiments, but other configurations, including those that may be desired, are also possible. Figure 5C , Figure 5D , Figure 5E The constructions shown in other variations can be used in other embodiments.

[0290] Next reference Figures 12A to 12C These figures illustrate example configurations for stacking the first elongated member 203. It has been found that, in some embodiments, heat distribution can be improved by stacking multiple bubbles. These embodiments can be even more advantageous when using an internally heated filament 215. Figure 12A A longitudinal section of the top portion of another composite pipe is shown. Figure 12A A cross-section of the composite tube 201 without any stacking is shown.

[0291] Figure 12B A longitudinal section of the top portion of another composite pipe is shown. Figure 12B Another example of a composite tube 201 with stacked bubbles is shown. In this example, the tops of two bubbles are stacked on top of each other to form a first elongated member 203. Figure 12A In comparison, the total height of the bubbles remains unchanged, but the pitch of the bubbles is... Figure 12A Half of it. Also, Figure 12B The embodiment in question only shows a slight reduction in the amount of air. The stacking of the bubbles reduces natural convection and heat transfer in the gaps between the bubbles 213, and lowers the overall thermal resistance. The increased heat flow path in the stacked bubbles makes it easier for heat to be distributed through the composite tube 201.

[0292] Figure 12C A longitudinal section of the top portion of another composite pipe is shown. Figure 12C Another example of a composite tube 201 with stacked bubbles is shown. In this example, the tops of three bubbles are stacked on top of each other to form a first elongated member 203. Figure 12A In comparison, the total height of the bubbles remains unchanged, but the pitch of the bubbles is... Figure 12A One-third. Also, Figure 12B The embodiment in question only shows a slight reduction in the amount of air. The stacking of the bubbles reduces natural convection and heat transfer in the gaps between the bubbles 213.

[0293] For reference Figure 13This illustrates additional possible characteristics of the second elongation member 205. The second elongation member 205 includes one or more coaxial cables 1301 having conductors 1303 surrounded by an insulation layer 1305, a protective layer 1307, and a sheath layer 1309. In some embodiments, the one or more cables 1301 may be multiaxial cables, i.e., multiple conductors 1303 are arranged within the insulation layer 1305. In this way, a single assembly containing multiple metal wires (including heating wires and / or sensing wires) can be used in the second elongation member 205, thereby simplifying the assembly and providing some protection against RF interference, etc. (via the protective layer 1307).

[0294] In some embodiments, one or more data transmission cables may be included in the second extension member 205. These data transmission cables may include fiber optic cables. In at least one embodiment, a single-fiber optical cable is included in the second extension member 205 and used in a passive mode. In a passive mode, a light source and a light sensor are provided at a first end of the cable. A reflector is provided at a second end. In use, the light source provides light with certain characteristics to the reflector. The reflector then reflects this light to the light sensor, and the characteristics of the reflected light can be determined by analysis. The reflector can be adapted to change the characteristics of the reflected light according to a characteristic of the system. For example, the reflector can be used to monitor condensation within an interface. The reflector may contain a material that changes color, for example, according to the condensation present at the second end. The reflector can alternatively or additionally contain a material that changes color, etc., according to the humidity level (relative or absolute humidity) and / or gas temperature at the second end; and / or gas composition such as inhaled O2 or exhaled CO2.

[0295] Refer again Figure 2B In some embodiments, a fluid (gas or liquid) flow may pass through the space within the first elongated member 203. In such embodiments, it is desirable that at least a portion of the first elongated member 203 is formed of a breathable material. Breathable here means substantially permeable to water vapor and substantially impermeable to liquid water and large volumes of gas. Suitable breathable materials include an activated perfluorinated polymer material with extremely hydrophilic properties, such as... Or hydrophilic polyester block copolymers, such as Other suitable materials include EVAQUA. TM and EVAQUA 2 TMThe catheter is a commercially available polymer from Fisher & Paykel Healthcare Ltd., Auckland, New Zealand. Suitable materials are further described in PCT Publication WO 2011 / 077250, filed December 22, 2010 and published June 30, 2011, and in U.S. Patent No. 6,769,431, filed May 8, 2001 and published August 3, 2003.

[0296] The flow through the first elongated member 203 can be used to dry or humidify the gas flow through the lumen 207 of the tube 201 as needed. Conversely, the flow through the lumen 207 of the tube 201 can be used to dry or humidify the gas flow through the first elongated member 203 as needed. Exhaled breathing gas can be carried through the first elongated member 203. As another example, a liquid such as liquid water can be carried. As another example, a humidified or saturated gas flow can be carried. As another example, a dry gas flow or a compressed ambient air flow can be carried. In the foregoing embodiments, the first elongated member 203 can be open at both ends to facilitate fluid flow through it. One end of the first elongated member 203 can be connected to a suitable source, such as a source of exhaled breathing gas, liquid water, humidified gas, dry gas, or compressed air, as needed. The other end can be connected to a suitable outlet or be permitted to be discharged into the atmosphere.

[0297] For example, refer to Figure 2B The portion 211 of the first elongated member 203 forming the cavity 207 of the tube 201 can be formed of a breathable material as described above. The outward-facing portion 219 of the first elongated member 203 (facing the ambient atmosphere and away from the cavity) can be formed of an impermeable material, i.e., a material that is clearly impermeable to water vapor, liquid water, or a large flow of gas, as described elsewhere in this disclosure. In use, some humidifying fluid (such as water) can pass through the space formed by the first elongated member 203. Because the humidifying fluid is heated (e.g., by a heating filament 215 disposed in the second elongated member 205), a portion of the humidifying fluid will tend to evaporate. The water vapor can then pass through the breathable portion 211 into the large flow of gas passing through the cavity 207, thereby humidifying the large flow of gas. In this embodiment, the combination of the humidifying fluid, the first elongated member 203, and the heating filament 215 can provide a means for humidifying the gas flow within the cavity 207, thus allowing the system to omit a separate humidifier.

[0298] As another example, the gas flow can pass through the space within the first elongated member 203. For instance, it can carry exhaled breathing gas. See again... Figure 2B The first elongated member 203, or at least its outward-facing portion 219, is made of a breathable material as described above. In this way, as the exhaled gas moves along the length of the first elongated member 203, it tends to dry the gas at the patient end, where the relative humidity is about 100%, to reduce the humidity level at the opposite end.

[0299] Co-extrusion is a suitable method for forming a first elongated member 203 comprising a portion (211 or 219, depending on the desired application) formed of a breathable material and a portion (219 or 211, depending on the desired application) formed of an impermeable material.

[0300] Furthermore, although some of the foregoing embodiments have been described with reference to a single first elongated member 203 including a breathable portion and a leak-proof portion, it should be understood that the desired result (such as gas flow within the humidification cavity 207) can also be achieved using multiple first elongated members 203. Figure 12B , Figure 12C , Figure 37A and Figure 37B Suitable embodiments are shown in the figure.

[0301] Figure 37A A cross-section of a tube including two first elongated members is shown. A first elongated member 203a is disposed near the lumen 207 of the tube. A second first elongated member 203b faces the ambient atmosphere and is away from the lumen 207. The interior of the first elongated member 203a forms the wall of the lumen 207. The first elongated member 203a can define a conduit for a humidifying fluid such as liquid water. The first elongated member 203a can be formed of a breathable material. Since the humidifying fluid is heated (e.g., by a heating filament 215 disposed in the second elongated member 205), a portion of the humidifying fluid will tend to evaporate. Water vapor can then pass through the wall of the first elongated member 203a into the large volume of gas flowing through the lumen 207, thereby humidifying the large volume of gas. In this embodiment, the combination of the humidifying fluid, the first elongated member 203a, and the heating filament 215 provides a means for humidifying the gas flow within the cavity 207, thus eliminating the need for a separate humidifier. It should be understood that... Figure 37A The dimensions shown are not necessarily drawn to scale. For example, as Figure 12B As shown, the first elongated member 203a can be relatively large, and the second elongated member 203b can be relatively small. It should also be understood that the heating filament 215 is not necessarily housed within the second elongated member 205. For example, as... Figure 12BAs shown, the second elongating member may be omitted. The heating filament 215 may, for example, be housed in a portion of the second first elongating member 203b near the first first elongating member 203a.

[0302] Figure 37B A cross-section of a tube including two first elongated members is also shown. A first elongated member 203a is disposed near the lumen 207 of the tube. A second first elongated member 203b faces the ambient atmosphere and is away from the lumen 207. An interior portion of the first elongated member 203a forms part of the wall of the lumen 207. An interior portion of the second elongated member 203b also forms part of the wall of the lumen 207. (See above reference) Figure 37A As discussed, the first elongated member 203a can define a conduit with a humidifying fluid such as liquid water, and the combination of the humidifying fluid, the first elongated member 203a, and the heating filament 215 can provide a means for humidifying the gas flow within the cavity 207, thus allowing the system to omit a separate humidifier. It should also be understood that... Figure 37B The dimensions shown are not necessarily drawn to scale. For example, as Figure 12B As shown, the first elongated member 203a can be relatively large, and the second elongated member 203b can be relatively small. It should also be understood that the heating filament does not necessarily have to be housed in the second elongated member. For example, as... Figure 12B As shown, the second elongating member can be omitted. The heating filament can, for example, be housed in a portion of the second first elongating member 203b proximal to the first first elongating member 203a. Referring now... Figure 14A -14E and Figure 15A –15E shows some variations of the construction of the composite tube 201, which are adapted to provide increased lateral extension in the composite tube 201. Figure 15A –15E respectively show Figure 14A –14E shows a stretched state of the composite tube.

[0303] include Figure 14A , Figure 14B and Figure 14E Some embodiments of the tube shown include a second elongation member 205 having a shape that enhances its stretchability. For example, in Figure 14A In this structure, the second elongated member 205 is substantially oval, and its profile height is substantially the same as that of the first elongated member 203. For example... Figure 15A As shown, this allows the second elongated member 205 to deform outward to at least twice its width, compared to when it is stationary. Figure 14B and 14EIn the middle, the second elongated member 205 is shaped to have an accordion-like form. During extension, it is flattened (as shown in the diagram). Figure 15B and Figure 15E As shown in the diagram, the second elongation member 205 can therefore accommodate the increased amount of extension.

[0304] exist Figure 14C and Figure 14D In the middle, the first elongating member 203 has a shape that can be deformed outward, thereby increasing its lateral extension (as shown in the figures below). Figure 15C and Figure 15D (as shown in the image).

[0305] Medical circuit

[0306] Next reference Figure 16 The figure illustrates an example medical circuit according to at least one embodiment. The circuit includes one or more composite tubes as described above, i.e., for an inspiratory tube 103 and / or an expiratory tube 117. The characteristics of the inspiratory tube 103 and the expiratory tube 117 are as described above for... Figure 1 The tubes described are similar. The inhalation tube 103 has an inlet 109 communicating with the humidifier 107, and an outlet 113 through which humidified gas is supplied to the patient 101. The exhalation tube 117 also has an inlet 109 for receiving exhaled humidified gas from the patient, and an outlet 113. (As described above regarding...) Figure 1 The outlet 113 of the exhalation tube 117 can discharge exhaled gas to the atmosphere, the ventilator / fan device 105, the air scrubber / filter (not shown), or any other suitable location.

[0307] As described above, the heating filament 215 can be placed in the inhalation tube 103 and / or the exhalation tube 117 to reduce the risk of rain wash effect in the tube by maintaining the tube wall temperature above the dew point temperature.

[0308] Components of the blowing system

[0309] Laparoscopic surgery (also known as minimally invasive surgery (MIS) or keyhole surgery) is a modern surgical technique in which intra-abdominal procedures are performed through smaller incisions (typically 0.5 to 1.5 cm) compared to the larger incisions required for conventional surgery. Laparoscopic surgery involves procedures within the abdominal or pelvic cavity. In laparoscopic procedures using inflatable systems, it may be necessary to humidify the inflated gas (usually CO2) before it is delivered into the abdominal cavity. This helps prevent the patient's internal organs from becoming dehydrated and can reduce the amount of time required for postoperative recovery. Inflatable systems typically consist of a humidifier chamber that holds a certain amount of water within it. The humidifier usually includes a heater plate that heats the water to produce steam, which is then delivered into the incoming gas to humidify it. The steam is then used to expel the gas from the humidifier.

[0310] Next reference Figure 17 The figure illustrates a blowing system 1701 according to at least one embodiment. The blowing system 1701 includes a blower 1703 that generates a stream of blown gas at a pressure higher than atmospheric pressure for delivery into the abdominal or peritoneal cavity of a patient 1705. This gas enters a humidifier 1707, which includes a heater base 1709 and a humidifier chamber 1711, wherein the chamber 1711 contacts the heater base 1709 during use, thereby enabling the heater base 1709 to provide heat to the chamber 1711. In the humidifier 1707, the blown gas passes through the chamber 1711, thereby humidifying it to a suitable humidity level.

[0311] System 1701 includes a delivery conduit 1713 connected between a humidifier chamber 1711 and the peritoneal cavity or surgical site of patient 1705. The conduit 1713 has a first end and a second end; the first end is connected to an outlet of the humidifier chamber 1711 and receives humidified gas from the chamber. The second end of the conduit 1713 is placed in the surgical site or peritoneal cavity of patient 1705, and the humidified gas is blown from the chamber 1711 through the conduit 1713 into the surgical site to inflate it. The system also includes a controller (not shown) that regulates the humidity of the gas supplied by controlling the power supplied to the heater base 1709. The controller can also be used to monitor water in the humidifier chamber 1711. A smoke extraction system 1715 is shown extending from the body cavity of patient 1705.

[0312] The smoke extraction system 1715 can be used in conjunction with the air blowing system 1701 described above, or it can be used with other suitable air blowing systems. The smoke extraction system 1715 includes an exhaust or venting branch pipe 1717, an exhaust assembly 1719, and a filter 1721. The exhaust branch pipe 1717 connects the filter 1721 and the exhaust assembly 1719, and is positioned in or near the surgical site or peritoneal cavity of the patient 1705 during use. The exhaust branch pipe 1717 is a self-supporting tube with two open ends (i.e., the tube is capable of supporting its own weight without collapsing): an operating site end and an outlet end.

[0313] At least one embodiment includes the following implementation: using a composite tube as a conduit 1713 allows for the delivery of humidifying gas to the surgical site of the patient 1705 with minimal heat loss of the humidifying gas.

[0314] coaxial tube

[0315] The coaxial breathing tube may also include a composite tube as described above. In the coaxial breathing tube, the first gas space is an inspiratory or expiratory branch, and the second gas space is the other inspiratory or expiratory branch. A gas passage is provided between the inlet and outlet of the inspiratory branch, and a gas passage is provided between the inlet and outlet of the expiratory branch. In one embodiment, the first gas space is the inspiratory branch, and the second gas space is the expiratory branch. Alternatively, the first gas space may be the expiratory branch, and the second gas space may be the inspiratory branch.

[0316] Next reference Figure 18 The figure illustrates a coaxial tube 1801 according to at least one embodiment. In this example, a coaxial tube 1801 is provided between the patient 1801 and the ventilator 1805. Exhaled and inhaled gases each flow in an inner tube 1807, or in a space 1809 between the inner tube 1807 and the outer tube 1811. It will be understood that the outer tube 1811 may not be precisely aligned with the inner tube 1807. Additionally, "coaxial" means that one tube is located inside another tube.

[0317] Due to heat transfer, the inner tube 1807 carries inhaled gas in its internal space 1813, while exhaled gas is carried in the space 1809 between the inner tube 1807 and the outer tube 1811. This airflow configuration is indicated by arrows. However, the opposite configuration is also possible, in which the outer tube 1811 carries inhaled gas, while the inner tube 1807 carries exhaled gas.

[0318] In at least one embodiment, the inner tube 1807 is formed of a bellows, such as the Fisher & Paykel RT100 disposable tube. The outer tube 1811 may be formed of a composite tube as described above.

[0319] Using coaxial tubing 1801, ventilator 1805 may not notice a leak in inner tubing 1807. This leak could short-circuit patient 1801, meaning that patient 1801 will not receive sufficient oxygen. This short-circuit can be detected by placing a sensor at the patient end of coaxial tubing 1801. This sensor can be located in the patient end connector 1815. A short-circuit closer to ventilator 1805 will continue to cause patient 1801 to re-breathe the amount of air closer to patient 1801. This will increase the concentration of carbon dioxide in the inhaled airflow space 1813 close to patient 1801, which can be directly detected by a CO2 sensor. Such a sensor can include any number of currently commercially available such sensors. Alternatively, this rebreathing can be detected by monitoring the temperature of the gas in patient end connector 1815, where a temperature rise exceeding a predetermined level indicates that rebreathing has occurred.

[0320] In addition to reducing or eliminating the formation of condensate in the inner tube 1807 or outer tube 1811, and in order to maintain the temperature of the gas flowing through the coaxial tube 1801 at a substantially uniform temperature, a heater, such as a resistance heating filament, may be provided in the inner tube 1807 or outer tube 1811, and the heater may be located in the gas space 1809 or 1813, or within the wall of the inner tube 1807 or outer tube 1811 itself.

[0321] Nasal intubation and other patient interfaces

[0322] Next reference Figure 19A The figure illustrates a composite tube 201 used in conjunction with a nasal intubation patient interface 1901. In this example, the patient interface 1901 is positioned on the face of the patient 1903 using a head cap 1905 that is secured around the back of the patient 1901's head. The patient interface includes an intubation body 1907 and a delivery tube 1909. The composite tube 201, as described, communicates with the delivery tube 1909 to supply inhaled gas to the patient interface 1901.

[0323] In the past, delivery tube 1909 was used to decouple the weight of the heated breathing tube from the patient interface 1901. The previously used delivery tube 1909 consisted of a flexible tube of a certain length. Importantly, the delivery tube 1909 was lightweight, so that its mass would not pull the patient interface 1901 off the patient's face. The heated tube was essentially larger and heavier than the unheated tube. Therefore, the previously used delivery tube 1909 was unheated. To achieve satisfactory flexibility, the previously used delivery tube 1909 also had poor insulation properties. Without good insulation and heating, the rain-washing effect in the delivery tube 1909 was a problem. Therefore, the delivery tube 1909 was kept as short as possible to minimize the rain-washing effect. However, a shorter length could not always prevent the weight of the heated breathing tube from pulling off the patient interface 1901. Therefore, the previously used delivery tube had several disadvantages.

[0324] The composite tube 201 described herein provides good insulation while maintaining good flexibility and light weight. Therefore, in some embodiments, the delivery tube 1909 may be the composite tube 201. The composite tube 201 can provide improved insulation properties superior to delivery tubes previously known in the art. Furthermore, the delivery tube can be longer and provides better decoupling of tube drag. The delivery tube 201 of the composite tube 201 may optionally have heating filaments (not shown) in a second elongated member (not shown). The heating filaments (if present) can provide heat input. Alternatively, these heating filaments can provide structural support for the second elongated member when not powered.

[0325] The delivery tube 1909 of the unheated composite tube 201 can be longer than the normal unheated extension, while maintaining the same or less heat loss due to the better insulation properties of the composite tube 201. The increased length of the delivery tube 1909 helps prevent the tube from being pulled off by the patient's movement. The increased extension length will also allow for better head movement without compromising patient comfort.

[0326] Furthermore, some embodiments include the following implementation: eliminating the separate delivery tube 1909 can have several benefits, as discussed below. Therefore, as Figure 19B As shown, the delivery tube 1909 and the composite tube 201 may preferably be a single component that extends to the cannula body 1907.

[0327] In a typical patient interface 1901, a heating element (replacing) Figure 19AThe composite tube 201 supplies inhaled gas to the unheated delivery tube 1909. The temperature of the inhaled gas can experience significant heat loss (e.g., 20°C or greater or around that) along the length of the unheated delivery tube 1909. To compensate, the temperature of the patient end of the heated tube is maintained above the temperature actually required for delivery to the patient via the 1901. Furthermore, condensation occurs as the temperature within the delivery tube 1909 decreases, resulting in a rain-washing effect. It has been recognized that, as Figure 19B As shown, extending the heated composite tube 201 to the cannula body 1907 instead of the delivery tube 1909 reduces input energy requirements because the patient end of the composite tube 201 can be kept at a lower temperature. This configuration also reduces rain washout effects by eliminating the unheated delivery tube 1909 from the patient interface.

[0328] Desiredly, the composite tube 201 may be tapered. In at least one embodiment, the patient-side portion of the composite tube 201 is tapered to mate with the inlet of the cannula body 1907. In at least one embodiment, the diameter of the length of the composite tube 201 near the patient-side is smaller than the diameter of the rest of the composite tube 201. For example, the length of the composite tube 201 near the patient-side may be in the range of 50 to 300 mm (or about 50 to 300 mm). The smaller diameter of the tube near the patient-side can advantageously reduce the weight of the tube near the cannula body.

[0329] The composite tube 201 may include a temperature sensor (not shown) at least near the patient end of the composite tube 201. In addition to or instead of the temperature sensor, the composite tube 201 may also include another sensor (not shown) at least near the patient end of the composite tube 201. For example, the composite tube 201 may include a pressure sensor (not shown) at least near the patient end of the composite tube 201. A pressure sensor may be particularly advantageous for CPAP control and nasal high-flow therapy. When the composite tube 201 and the delivery tube 1909 are a single component, this or these sensors being located near the patient's nostril 1903 can provide more accurate information related to the delivered gas. An example patient-end sensor configuration is described in more detail below.

[0330] A single-unit construction is also desirable because it reduces wiring on the patient 1901. If the cannula body 1907 is equipped with one or more sensors or other electrical components, it is necessary to provide an electrical connection to the cannula body 1907. If the composite tube 201 and the delivery tube are a single unit, the wiring can extend along the composite tube 201 to the patient end of the composite tube 201 at the cannula body 1907, as described above. A separate electrical connection to the cannula body 1907 is not required.

[0331] As described above, a single construction can incorporate a variable-pitch composite tube 201. In tubes with little or no unheated extensions, heating continues on the insertion body 1907 where the sensing element will be positioned. These tubes require a reduced tube-end temperature to ensure delivery of saturated gas at 37°C. This is because, generally, tube-end temperatures are set well above 37°C to compensate for heat loss in the unheated extension. However, a construction without an unheated extension is more likely to experience condensation at the device end. Redistributing heat to the area near the device end of the tube will help facilitate T gas >T dew This reduces condensation and eliminates the need to deliver excessively high tube end temperatures.

[0332] It should be understood that, although Figure 19B The configuration may be preferred in some embodiments, but other configurations, including those that may be desired, are also acceptable. Figure 19A The construction shown can be used in other embodiments.

[0333] The composite tube 201 disclosed herein can also be combined with and / or used with other patient interfaces, such as the full face mask 2001. Figure 20A ), Nose mask 2003 ( Figure 20B ), and nose / pillow cover 2005 ( Figure 20C As described above, the composite tube 201 can serve as the delivery tube 1909 or completely eliminate the need for a delivery tube.

[0334] clean

[0335] Return again Figure 2A In at least one embodiment, the material used for the composite tube can be selected to handle different cleaning methods. In some embodiments, the composite tube 201 can be cleaned using an intensive sterilization process (approximately 20 cleaning cycles). During the intensive sterilization process, the composite tube 201 is pasteurized at approximately 75°C for approximately 30 minutes. Next, the composite tube 201 is immersed in 2% glutaraldehyde for approximately 20 minutes. The composite tube 201 is then removed from the glutaraldehyde and immersed in 6% hydrogen peroxide for approximately 30 minutes. Finally, the composite tube 201 is removed from the hydrogen peroxide and immersed in 0.55% orthophthalaldehyde (OPA) for approximately 10 minutes.

[0336] In other embodiments, the composite tube 201 can be cleaned using sterilization (approximately 20 cycles). First, the composite tube 201 is placed in autoclave steam at approximately 121°C for approximately 30 minutes. Next, the temperature of the autoclave steam is increased to approximately 134°C for approximately 3 minutes. After autoclaving, the composite tube 201 is surrounded by 100% ethylene oxide (ETO) gas. Finally, the composite tube 201 is removed from the ETO gas and immersed in approximately 2.5% glutaraldehyde for approximately 10 hours.

[0337] The composite tube 201 may be made of a material capable of withstanding repeated cleaning processes. In some embodiments, part or all of the composite tube 201 may be made of, but is not limited to, a styrene-ethylene-butene-styrene block thermoplastic elastomer, such as Kraiburg TF6STE. In other embodiments, the composite tube 201 may be made of, but is not limited to, a thermoplastic polyester elastomer, polyurethane, or silicone.

[0338] Manufacturing method

[0339] Next reference Figures 21A to 21F These figures illustrate example methods for manufacturing composite pipes.

[0340] First go to Figure 21A In at least one embodiment, a method of manufacturing a composite tube includes providing a second elongated member 205 and helically wrapping the second elongated member 205 around a mandrel 2101, wherein opposite edge portions 2103 of the second elongated member 205 are spaced apart on adjacent sheaths, thereby forming a second elongated member helix 2105. In some embodiments, the second elongated member 205 may be directly wrapped around the mandrel. In other embodiments, a sacrificial layer may be provided on the mandrel.

[0341] In at least one embodiment, the method further includes forming a second elongated member 205. Extrusion is a suitable method for forming the second elongated member 205. A second extruder can be configured to extrude the second elongated member 205 at a specific bead height. Therefore, in at least one embodiment, the method includes extruding the second elongated member 205.

[0342] like Figure 21BAs shown, extrusion can be advantageous because it allows the heating filament 215 to be encapsulated within the second elongated member 205 during its formation, for example, using an extruder with a crosshead die. Therefore, in some embodiments, the method includes providing one or more heating filaments 215 and encapsulating the heating filaments 215 to form the second elongated member 205. The method may also include providing a second elongated member 205 having one or more heating filaments 215 embedded or encapsulated within it.

[0343] In at least one embodiment, the method includes embedding one or more filaments 215 within the second elongation member 205. For example, as... Figure 21C As shown, the filament 215 can be pressed (pulled into or mechanically positioned) into the second elongated member 205 to a specific depth. Alternatively, slits can be made in the second elongated member 205 to a specific depth, and the filament 215 can be placed in these slits. Preferably, the extrusion or cutting is performed shortly after the second elongated member 205 is extruded, and the second elongated member 205 is flexible.

[0344] like Figure 21D and Figure 21E As shown, in at least one embodiment, the method includes providing a first elongation member 203 and helically wrapping the first elongation member 203 around a second elongation member helix 2105 such that a plurality of portions of the first elongation member 203 overlap with adjacent sleeves of the second elongation member helix 205, and a portion of the first elongation member 203 is disposed adjacent to a mandrel 2101 located in the space between the sleeves of the second elongation member helix 2105, thereby forming a first elongation member helix 2107. Figure 21D An example method is shown in which a heating filament 215 is encapsulated in a second elongation member 205 prior to the formation of the second elongation member spiral. Figure 21E An example method is shown in which a heating filament 215 is embedded in the second elongated member 205 when the second elongated member spiral 2105 is formed. An alternative method of incorporating the filament 215 in the composite tube includes encapsulating one or more filaments 215 between the first elongated member 203 and the second elongated member 205 in the region where the first elongated member 203 and the second elongated member 205 overlap.

[0345] As described above, at least one embodiment includes a tube having multiple sheaths of a first elongated member 203 between the sheaths of a second elongated member 205. Therefore, in some embodiments, the method includes providing a first elongated member 203 and helically wrapping the first elongated member 203 around a second elongated member spiral 2105 such that a first side of the first elongated member 203 overlaps with the sheaths of the second elongated member spiral 2105, and a second side of the first elongated member 203 contacts a portion of its adjacent side. A portion of the first elongated member 203 is disposed near a mandrel 2101, in the space between the sheaths of the second elongated member spiral 2105, thereby forming a first elongated member spiral 2107 that includes multiple sheaths of the first elongated member 203 between the sheaths of the second elongated member 205.

[0346] In at least one embodiment, the first elongated member 203 is wrapped multiple times within a multi-turn second elongated member 205. Figure 22A A schematic diagram of the resulting longitudinal cross-section is shown. Any suitable technique, such as thermal melting, adhesion, or other attachment mechanism, can be used to fuse the adjacent sheaths of the first elongated member 203. In at least one embodiment, adjacent molten or softened bubbles can come into contact together and thus bond while hot, followed by cooling with air jet. They can also be joined together by winding the adjacent sheaths of the softened first elongated member 203 onto a mandrel and then cooling them.

[0347] In at least one embodiment, the first elongated member 203 is wrapped once or multiple times in a plurality of turns of the second elongated member 205, and using suitable techniques, such as heat treatment, one or more bubbles between the plurality of turns of the second elongated member 205 are further collapsed into additional discrete bubbles. Figure 22B A schematic diagram of the resulting longitudinal section is shown in the figure. Figure 22B As shown, using any suitable technique, such as applying mechanical force by an object or applying force by a directed air jet, one bubble of the first elongating member 203 can collapse into two or three or more discrete bubbles. Figure 22C The diagram shows another example of the resulting longitudinal cross-section. In this example, the central portion of the bubble collapses, causing the top and bottom of the bubble to merge to form two discrete bubbles separated by a flat bottom portion. The adjacent portions of these two discrete bubbles are then joined to form a structure comprising three discrete bubbles.

[0348] The aforementioned alternative of combining one or more heating filaments 215 with the composite tube has advantages over alternatives that have heating filaments in the gas path. Having one or more heating filaments 215 outside the gas path improves performance because these filaments heat the tube wall where condensation is most likely to occur. This configuration reduces the risk of ignition in high-oxygen environments by removing the heating filaments from the gas path. This feature also reduces performance because it reduces the heating efficiency of the heating filaments on the gas passing through the tube. However, in some embodiments, the composite tube 201 includes one or more heating filaments 215, which are placed within the gas path. For example, the heating filaments can be placed on the tube wall (tube opening), such as in a helical configuration. An example method for placing one or more heating filaments 215 on the tube wall includes bonding, embedding, or otherwise forming a heating filament on the surface of the second elongated member 205, thus forming the tube wall during assembly. Therefore, in some embodiments, the method includes placing one or more heating filaments 215 on the wall of the lumen.

[0349] Whether or not the heating filament 215 is embedded or encapsulated on or disposed on the second elongation member 205, or otherwise placed in or on the tube, in at least one embodiment, the paired filaments may form a connecting loop at one end of the composite tube to form a circuit.

[0350] Figure 21F It shows Figure 21E The longitudinal section of the component shown is concentrated at the top end portion of the mandrel 2101 and the top end portions of the first elongation member spiral 2107 and the second elongation member spiral 2105. This example shows the second elongation member spiral 2105, which has a T-shaped second elongation member 205. When the second elongation member is formed, the heating filament 215 is embedded in the second elongation member 205. Figure 21F The right side shows the bubble-shaped outline of the spiral of the first elongated member as described above.

[0351] The method may also include forming a first elongated member 203. Extrusion is a suitable method for forming the first elongated member 203. Thus, in at least one embodiment, the method includes extruding the first elongated member 203. The first elongated member 203 can also be manufactured by extruding two or more portions and combining them together to form a single workpiece. As another alternative, the first elongated member 203 can also be manufactured by extruding segments that produce a hollow shape during adjacent formation or bonding in a spiral tube forming process.

[0352] The method may further include supplying a gas at a pressure greater than atmospheric pressure to one end of the first elongated member 203. This gas may be, for example, air. Other gases may also be used, as explained above. Supplying a gas to one end of the first elongated member 203 can help maintain the shape of an open, hollow body as the first elongated member 203 wraps around the mandrel 2101. The gas may be supplied before, during, or after the first elongated member 203 wraps around the mandrel 2101. For example, an extruder with a die / pointer combination may supply or introduce air into the hollow chamber of the first elongated member 203 during extrusion of the first elongated member 203. Therefore, in at least one embodiment, the method includes extruding the first elongated member 203 and, after extrusion, supplying a gas at a pressure greater than atmospheric pressure to one end of the first elongated member 203. A pressure of 15 to 30 cm H2O (or approximately 15 to 30 cm H2O) was found to be suitable.

[0353] In at least one embodiment, the first elongated member 203 and the second elongated member 205 are helically wound around the mandrel 2101. For example, the first elongated member 203 and the second elongated member 205 may emerge from the extrusion die at an elevated temperature of 200°C (or about 200°C) or above, and then be applied to the mandrel after a short distance. Preferably, the mandrel is cooled to a temperature of 20°C (or about 20°C) or below, for example, near 0°C (or about 0°C), using a water jacket, cooler, and / or other suitable cooling method. After five (or about five) helical wraps, the first elongated member 203 and the second elongated member 205 are further cooled by a cooling fluid (liquid or gas). In one embodiment, the cooling fluid is air emanating from a ring, with the airflow surrounding the mandrel. After cooling and removal of the components from the mandrel, a composite tube is formed having a lumen extending along a longitudinal axis and a hollow space around the lumen. In this embodiment, no adhesive or other attachment device is required to connect the first elongated member and the second elongated member. Other embodiments may utilize an adhesive or other attachment device to bond or otherwise connect the two components. In another embodiment, after extrusion and placement of the heated filament, the second elongated member 205 may be cooled to freeze portions of the heated filament. Then, when applied to a mandrel, the second elongated member 205 may be reheated to enhance bonding. Example methods for reheating include using localized heating devices, heating wheels, etc.

[0354] The method may also include forming a connecting loop at one end of the composite tube with a pair of heating filaments or sensing filaments. For example, the ends of two heating filaments or sensing filaments can be peeled from the second elongation member 205, and then the two filaments can be formed together as a connecting loop, for example by tying, bonding, welding, adhering, fusing, etc. As another example, during the manufacturing process, the ends of the heating filaments can be detached from the second elongation member 205 and then formed as connecting loops when assembling the composite tube.

[0355] For reference Figure 23A –23H, An alternative method for forming tube 201 involves an extrusion tool 2301 having a set of flow paths extending thereal. The extrusion tool 2301 can be used to form tubes, such as… Figure 23G and Figure 23H The example tube shown is illustrated. As shown, the tube produced using extrusion tool 2301 may include a plurality of first elongated members 203 that extend generally along the longitudinal axis of the tube. In some embodiments, extrusion tool 2301 includes a body 2310 and a central extension 2320. In some embodiments, the body 2310 and the extension 2320 are generally cylindrical. The body 2310 may include one or more flow paths 2312 that allow molten plastic or another material to flow through the body 2310 from an inlet end 2314 to an outlet end or extension end 2316. In some embodiments, these flow paths have a substantially tapered longitudinal cross-section (i.e., wider where the molten plastic first enters at the inlet end 2314 and narrower near the extrusion end 2316). These flow paths may be configured differently to produce tubes 201 with different profiles. For example, in Figure 23C and Figure 23D The flow path configuration shown at the output or extension 2316 can produce tube 201, the end view features of which are as follows: Figure 23A As shown in the image. Figure 21B It shows Figure 23A An end view of the tube, which includes a second elongation member 205, which may include heating filaments 215 disposed between adjacent bubbles or between first elongation members 203. In use, tool 2301 can be adapted to rotate to guide the helical forming tube 201. Figure 23F As shown, the central extension 2320 couples the extrusion tool 2301 to an extruder 2330. A bearing 2322, disposed between the central extension 2320 and the extruder 2330, allows the central extension 2320 and the body 2310 to rotate relative to the extruder 2330. The rotational speed of the tool 2301 can be adjusted to change the pitch or helix angle of the first elongation member 203. For example, a faster rotational speed can produce a smaller helix angle, such as... Figure 23GAs shown in the diagram. Slower rotational speeds can produce larger helix angles, such as... Figure 23H As shown in the image.

[0356] As referenced above Figure 8A and Figure 8B As discussed, some embodiments may include a composite tube with a variable pitch. In manufacturing such embodiments, a mandrel 2101 and a control system are preferably provided, which can change the effective pitch (i.e., the "ropes") of the first elongation member 203 and the second elongation member 205. This can be achieved, for example, by controlling the ratio of the stranding speed to the advance speed of the mandrel 2101 while maintaining a constant tangential speed at a critical dimension (i.e., the pitch center diameter of the ropes). The pitch center diameter determines that the pitch center passes through the middle of the ropes. This value depends on the speed. Therefore, it can also be predicted that if the pitch center diameter is different from the expected value, the speed can be adjusted to bring the pitch center diameter back to the desired value. Changing the effective pitch can also be achieved, for example, by controlling the ratio of the stranding speed to the advance speed of the mandrel 2101 while maintaining a constant rotational speed of the helical composite tube 201 thus formed. By controlling the stranding speed, any variation in the extrudate output can be compensated for.

[0357] Another method for manufacturing a variable pitch composite tube 201 uses an integrated system in which the extrusion speed and the advance speed of the mandrel 2101 are uniformly changed. For example, in this mode, the stranding speed can remain the same, but the advance of the mandrel 2101 will need to slow down the extrusion speed when enabled so that the extrudate output matches the tangential speed of the helical tube 201 thus formed.

[0358] Another method for manufacturing the variable pitch composite tube 201 involves moving the incident angles of the second elongated member 205 and the first elongated member 203 to change the pitch of the tube 201. In these embodiments, the extruder may be on a chute, such as a rotary table, which allows for angle changes, with the center of rotation located where the second elongated member 205 and the first elongated member 203 meet the mandrel 2101. This method can allow for pitch changes of up to 3–5 mm (or about 3–5 mm).

[0359] Next reference Figures 24A to 24FThese figures illustrate cross-sections of tubes comprising monotube-shaped elements having a first elongated member or portion 203 and a second elongated member or portion 205. As illustrated, the second elongated portion 205 is integrated with the first elongated portion 203 and extends along the entire length of the monotube-shaped element. In the illustrated embodiment, such a monotube-shaped element is an elongated hollow body having a relatively thin wall in its cross-section that partially defines the hollow portion 2201, and two reinforcing portions 205 of relatively greater thickness or stiffness on opposite sides of the relatively thin wall adjacent to the elongated hollow body. After the elongated hollow body is helically wound, these reinforcing portions form part of the inner wall of a lumen 207, such that these reinforcing portions are also helically positioned between adjacent turns of the elongated hollow body.

[0360] In at least one embodiment, the method includes forming an elongated hollow body including a first elongated portion 203 and a reinforcing portion 205. Extrusion is a suitable method for forming the elongated hollow body. Figures 24A to 24F The diagram shows a suitable cross-sectional shape for this tubular element.

[0361] The elongated hollow body can be formed into a medical tube as explained above, and this reference is made in conjunction with the preceding discussion. For example, in at least one embodiment, a method of manufacturing a medical tube includes spirally wrapping or winding the elongated hollow body around a mandrel. This can be done at elevated temperatures, allowing the elongated hollow body to cool after being spirally wound to hold adjacent loops together. Figure 24B As shown, the opposite edge portions of the reinforcing portion 205 may contact each other on adjacent rings. In other embodiments, the opposite edge portions of the second elongating member 205 may overlap on adjacent rings, as shown... Figure 24D and Figure 24E As shown in the diagram. The heating filament 215 can be incorporated into the second elongated member, as explained above and as... Figures 24A to 24F As shown in the diagram. For example, a heating filament can be provided on the opposite side of the elongated hollow body, for example... Figure 24A As shown in –24D. Alternatively, the heating filament can be provided only on one side of the elongated hollow body, for example... Figure 24E As shown in –24F. Any of these embodiments can also be combined with sensing the presence of a filament.

[0362] Placement of electrical connection chamber end connectors

[0363] Next reference Figure 25A This illustrates an example flow diagram for attaching a connector to the end of a tube configured for use with a humidifier. For example, as referenced above... Figure 1The inlet 109 of the air intake pipe 103 is connected to the humidifier 107 via port 111. Figure 25A The example flowchart can create an inlet 109 that can be physically and electrically connected to the humidifier 107.

[0364] In this example, seal 2503 is inserted into seal housing 2501. Figure 25B The insertion behavior of the seal is shown in more detail. The seal housing 2501 is made of a molded plastic. The open end is sized and configured for connection to the humidifier. The seal 2503 can be an O-ring, such as... Figure 25B As shown in the diagram. A suitable construction for the O-ring can be a double-ring configuration, comprising a thicker concentric ring connected by a thinner sleeve. In this example, the O-ring is molded from a single elastic material, such as rubber or silicone. A seal 2503 is located in a compliant bulge within the seal housing 2501. The seal 2503 is designed to seal the outer surface of the port of the humidifier chamber. The seal 2503 can deflect or extend along the outer surface of the port. In other words, the double O-ring configuration comprises an inner O-ring and an outer O-ring connected by a flange. The outer O-ring is sealed within the connection, while the inner O-ring can deflect along the flange portion and press against the outer surface of the port. In this configuration, the horizontal plane extending through the central axis of the inner O-ring and the horizontal plane extending through the central axis of the outer O-ring can be in different planes.

[0365] Turn to Figure 25A For example, a printed circuit board (PCB) is inserted into a compliant dock on the sealing housing 2501. Figure 25C The PCB insertion behavior is shown in more detail below. Figure 25C In this assembly, a component 2505 including a PCB and PCB electrical connectors is inserted into a conforming portion on a sealing housing 2501. Various PCBs with suitable sizes and constructions can be used. Various PCB electrical connectors can also be used. For example, the PCB electrical connectors can be through connectors or bidirectional connectors. The PCB includes four connecting pads adapted to receive four conductive filaments enclosed in a second elongated member of the tube. However, if the second elongated member contains more or fewer than four conductive filaments, the PCB can be configured to receive a suitable number of conductive filaments.

[0366] Turn to Figure 25A Instances, and as Figure 25DAs shown in more detail, the sealing ring 2507 is clamped onto an open end of the sealing housing 2501, with the sealing element 2503 situated on the compliant protrusion. Clamping the sealing ring 2507 in place presses the sealing element 2503, thereby forming a liquid-resistant and gas-resistant connection between the sealing housing 2501 and the sealing ring 2507. In this example, the sealing ring 2507 is made of a molded plastic. In this example, the sealing ring 2507 also includes a protrusion whose size and shape mate with the PCB. This protrusion serves to support and protect the more flexible and fragile PCB. However, in some embodiments, this protrusion may be omitted. The resulting assembly, including the sealing housing 2501, the sealing element 2503, the PCB and PCB connector assembly 2505, and the sealing ring 2507, is herein referred to as the connector tube assembly 2515.

[0367] Turn to Figure 25A For example, the tube is prepared for connection to the connector tube assembly 2515. Figure 25A As shown and more detailed as Figure 25E As shown, in step 2511, a portion of the second elongated member at one end of the tube is separated from the first elongated member. Then, in step 2513, a certain length of the separated second elongated member is peeled off to expose four conductive filaments (or the number thereof, which is the number of conductive filaments contained in the second elongated member). Figure 25F Step 2513 is shown in more detail below.

[0368] like Figure 25A The explanation in the text is as follows: Figure 25G As shown in more detail, this portion of the tube, having the stripped length of the second elongation member, is inserted into the connector tube assembly 2515. Figure 25G In this configuration, the second elongated member 205 has a curved shape to accommodate the positioning of the PCB connector assembly 2505. The PCB connector assembly 2505 can also be sized and positioned to reduce or eliminate the curved shape, for example, by further moving the PCB connector assembly toward the connector end. Figure 25A and Figure 25H As shown in step 2517, these four conductive filaments are inserted into the four connection pads of the PCB. Then, as... Figure 25A and Figure 25I As shown, solder beads 2519 are placed on each filament-connector pad to secure the filament to the pad and ensure good electrical connection between each filament and its corresponding pad.

[0369] In some embodiments, the aforementioned step of placing solder beads 2519 may be omitted. Figure 26A–26E shows an example connector assembly construction that does not require welding to attach the filament to the connector assembly.

[0370] Figure 26A A connector assembly 2601 is shown, comprising a clip housing 2603 and a circuit connector 2605. A second elongated member 205 of stripped length 2607 exposes a heating filament 215 that can be inserted into clips 2609 within the clip housing 2403. Each clip 2609 is conductive. Suitable materials for the clips 2609 include, for example, aluminum, copper, and gold. The clips 2609 hold a heating filament 215 without the need for solder. Electrical wires 2611 can extend between the individual clips 2609 and the circuit connector 2605.

[0371] Figure 26B A top view of the connector assembly 2601 is shown, showing the clip 2609 positioned in the clip housing 2603.

[0372] Figure 26C Clip 2609 is shown in more detail. Clip 2609 includes a folded portion 2613, a retaining tab portion 2615, a flange portion 2617, and an extension portion 2619. A heating wire (not shown) is inserted into the flange portion 2617, such that the folded portion 2613 receives and retains the heating wire. The shape of the flange portion 2617 facilitates the insertion of the heating wire and guides it into place. However, the flange portion 2617 can have a straight shape, if desired. The flange portion 2617 can also have another suitable shape, such as a partial flange. The folded portion has a capturing portion 2621 conforming to the retaining tab portion 2615. The retaining tab portion 2615 is angled, such that a heating wire can slide in one direction across the retaining tab portion 2615 into the folded portion 2613. The retaining tab portion 2615 also captures the heating wire to prevent it from accidentally falling out of the folded portion 2613. The elongated portion 2619 is conductive and carries current from the heating filament to and / or through the clip housing 2603.

[0373] Figure 26D yes Figure 26C The view shows a cross section and the positioning of the splice portion 2615 and the snap-fit ​​portion 2621 in more detail. Figure 26E This shows how the clip 2609 is positioned within the clip housing 2603. The clip housing 2603 is shown transparently to demonstrate the positioning of the extension 2619.

[0374] Refer again Figure 25ATo ensure that all components of the connecting tube assembly 2515 are reliably secured to each other, a layer of adhesive 2521 is then applied. Adhesive is a broad term and refers to a material used to bond, fix, or attach other materials. When adhesive is liquid or semi-solid, it can be tacky or sticky to the touch. When adhesive dries or otherwise cures into a solid state, it can be tacky or non-tacky, or not sticky to the touch. Adhesive can be a resin, such as epoxy resin, or an elastomer (thermosetting or thermoplastic). Using TPE materials can be advantageous because they are generally flexible and can withstand torsion, bending, or stress without breaking.

[0375] exist Figure 25J An example method for applying adhesive 2521 is shown. In this method, a two-block mold is provided. In this example, the mold is made of a metal such as aluminum or stainless steel; however, any suitable material can be used. For example, the mold could be made of... The PTFE modules are made of PTFE. One module is configured to accommodate the protruding PCB of the connector tube assembly 2515 and the PCB connector assembly 2505, as well as the adjacent tube, and another module is configured to accommodate the tube and the opposing portion of the connector tube assembly 2515. The tube is placed in a conforming mold such that these modules are stacked on top of one another. A liquid adhesive is introduced into the inlet hole of the mold and allowed to harden. The mold is then removed to expose the glued tube-connector assembly 2523, which includes a hardened adhesive layer 2521 covering the PCB and bonded between the tube and the connector tube assembly 2515. The adhesive layer can cover the PCB and all solder joints on the PCB. In this way, the adhesive layer can protect the PCB and its connections from corrosion. In other words, the adhesive serves at least three functions: sealing the connector and conduit, holding the PCB in place and encapsulating the PCB; the adhesive layer forms a pneumatic seal, a mechanical bond, and PCB encapsulation. In addition, the adhesive layer can act as an electrical insulating barrier, for example, by preventing moisture and liquid from reaching electrical components and creating a conductive path to the user of the device.

[0376] Return again Figure 25A The pipe-connector assembly 2523 is then in a state ready for final assembly. For example... Figure 25K As shown in more detail, the first clamshell member 2525 and the second clamshell member 2527 engage around the tube-connector assembly 2523, such that a portion of the PCB connector remains exposed. Figure 25K The first clamshell-shaped member 2523 and the second clamshell-shaped member 2527 shown are the top clamshell-shaped member and the bottom clamshell-shaped member, respectively.

[0377] Figure 27A–27E shows an alternative clamshell-shaped component design, wherein the first clamshell-shaped component 2525 and the second clamshell-shaped component 2527 are the left and right clamshell-shaped components, respectively. Clamshell-shaped components 2525 and 2527 are partially ( Figure 25K or Figure 27A –27E) can be made of molded plastic or any other suitable material. Clamshell-shaped parts 2525, 2527 ( Figure 25K or Figure 27A –27E) for further protection of tube-connector assembly 2523 ( Figure 25A and Figure 25J This allows the pipe-connector assembly to be held in a bent position, which during use facilitates the return of condensate to the humidifier unit. For example... Figure 25L As shown, the final component can be easily snapped into the humidifier, with compliant electrical connectors near the connection port.

[0378] Although the aforementioned manufacturing method is described with reference to a flowchart, this flowchart merely provides an example method for attaching the connector to the end of a tube configured to be connected to a humidifier in use. The method described herein does not imply a fixed order for these steps. Nor does it imply that any single step is required to perform the method. The embodiments can be performed in any order, and combinations thereof are also possible.

[0379] Placement of alternative device end connectors

[0380] Next reference Figure 28A -28F, these figures illustrate a connector that can be used for medical circuits with wires passing through it. Connector 2801 includes a circuit breaker 2802, which in some embodiments spans 30 mm (or approximately 30 mm). In some embodiments, one end of the circuit breaker 2802 has an L-shaped arm 2803 that extends partially outward from connector 2801 and is partially parallel to the longitudinal axis of connector 2801.

[0381] Arm 2803 may have one or more electrical conductors 2804 embedded therein. Conductors 2804 may be made of copper or brass or another material suitable for conducting electricity, and may be formed as a flat L-shaped workpiece that extends substantially along the length of arm 2803.

[0382] The connector 2801 may further include an inner portion 2805 adapted to be substantially located inside a portion of the tube 201; and an outer portion 2806 adapted to substantially surround a portion of the tube 201.

[0383] A portion of the second elongated member 205 is peeled off to expose one or more filaments 215 embedded therein. Preferably, about 5 mm of the filament 215 is exposed. A connector 2801 is then attached to the tube 215 such that the inner portion 2805 is located within the tube 201, and the outer portion 2806 is located around the tube 201. Preferably, the connector 2801 is oriented such that the exposed end of the filament 215 is located at or near the circuit breaker 2802.

[0384] The exposed ends of the filament 215 are then electrically and / or physically connected to the conductor 2804. This can be done by soldering these ends to the conductor 2804 or by any other method known in the art.

[0385] Member 2807 may be inserted into or molded on top of connector 2801 and optionally at least a portion of tube 201 to facilitate attachment between connector 2801 and tube 201. Member 2807 may be a rigid or soft material, such as soft rubber or elastomer.

[0386] In some embodiments, a generally L-shaped bend 2808 may be placed above the assembly. The bend 2808 may provide additional strength to the connection and may provide a predetermined bend in the tube 201 (so that the connector 2801 can be easily positioned on the body of the tube 201 at an angle of approximately 90° to the body).

[0387] Next reference Figure 29A –29L, these figures illustrate another connector 2901, which can be used in medical circuits with wires passing through it. First refer to… Figure 29A The connector 2901 allows the composite tube to be connected to a device such as a CPAP device (not shown). An electrical terminal is carried on the L-shaped arm 2903 of the connector 2901, which engages with complementary electrical terminals of the device to allow the transfer of electrical signals or energy between the device and the composite tube. In the illustrated arrangement, the electrical terminals of the connector 2901 are plugs 2905 conforming to the receiver or port of the device. However, this arrangement can be reversed if desired. In this example, the plug is electrically connected to an electrical contact 2906 for establishing an electrical connection with the composite tube. Here, the electrical contact 2906 is molded into the connector 2901. The connector 2901 further includes a filament frame 2907 also molded into the connector 2901. The connector 2901 also includes a circuit breaker 2902, which in some embodiments spans 30 mm (or approximately 30 mm).

[0388] like Figure 29B and Figure 29CAs shown, a portion of the second elongated member 205 (e.g., a 10-mm portion) is peeled off to expose one or more filaments 215 of a shorter length embedded therein. Preferably, about 5 mm or 10 mm of the filaments 215 are exposed.

[0389] like Figure 29E As shown, connector 2901 is then attached to tube 215 such that the inner portion 2909 of connector 2901 is located within tube 201, and the outer portion 2911 of connector 2901 is located around tube 201. Preferably, connector 2901 and composite tube 201 are oriented such that the exposed end of filament 215 is located at or near circuit breaker 2902, and filament 215 are aligned to meet near contact point 2906.

[0390] like Figure 29F As shown, the heating filaments 215 are positioned below the wire frame 2907, such that each heating filament 215 is positioned above the contact point 2906.

[0391] like Figure 29G As shown, solder beads 2913 are placed on each heating filament 215 at the corresponding contact point 2906. The combination of connector 2901 and composite tube 201 is here labeled as connector-tube assembly 2917. Figure 29H As shown, the molding tool core 2915 is inserted into the connector 2901. Figure 29I As shown, the connector-tube assembly 2917 and the core 2915 are placed in the injection molding tool 2919. Figure 29J In this process, a molding material 2921 is molded onto a circuit breaker (not shown), thereby joining the connector 2901 and the composite tube 201. Suitable molding materials 2921 include plastics and rubbers. The connector-tube assembly 2917 and the core 2915 are removed from an injection molding tool (not shown), as follows: Figure 29K As shown in the image.

[0392] like Figure 29L As shown, the core 2915 is removed, thereby providing the device end connector 2901 to the composite tube 201. Figure 29AThe method of –29J allows plug 2903 to be electrically connected to the heating filament and / or one or more other electrical components (not shown) of the composite tube 201. Preferably, the heating circuit of the device supplies electrical power to the heating filament of the composite tube 201, thereby enabling the heating filament to provide heat to the humidified airflow passing through the composite tube 201. As discussed herein, such an arrangement can prevent or limit condensation within the composite tube 201. Alternatively, plug 2903 and the device port can provide other electrical signals, such as data signals, for communication between the device and the composite tube 201. For example, a sensor at the patient interface end of the composite tube 201 can provide data on one or more parameters of the airflow (e.g., temperature, humidity level) for use by the device's control system. Any other desired electrical signals may also be transmitted.

[0393] The aforementioned method for attaching a connector to a composite pipe is provided by way of example. The described method does not imply a fixed order for the steps, nor does it imply that any single step is required to perform the method. The embodiments can be performed in any order, and combinations thereof are also possible.

[0394] Placement of patient-end connectors with electrical connections

[0395] Next reference Figure 30A –30O, these figures illustrate an example connector 3000 for connecting one end of tube 201 to a patient interface (not shown). The end of connector 3000 that connects to the patient interface is indicated by reference numeral 3001.

[0396] Figure 30A A side perspective view of connector 3000 is shown.

[0397] like Figure 30B As shown in –30F, connector 3000 includes PCB assembly 3003 and insert 3005, which are collectively referred to as insert assembly 3007 when assembled together, and cover 3009. Figure 30B -30D and Figure 30F Each showed a general similarity to Figure 30A The side perspective view corresponding to the view. Figure 30E A side-view top view is shown.

[0398] Insert 3005 and cap 3009 are preferably molded plastic parts. Insert 3005 can serve one or more purposes, including providing a receiver for tube 201, providing a suitable conduit for a gas flow path, providing a housing for PCB assembly 3003, and providing a housing for a sensor (not shown) such as a thermistor. Cap 3009 protects and covers the relatively fragile PCB assembly 3003 and protects the connection between tube 201 and insert 3005. Figure 30D and 30E As shown, the end of the insert 3005 inserted into the tube 201 (i.e., the end opposite to end 3001) can be angled, which helps in insertion into the tube 201. However, in some embodiments, the end opposite to end 3001 can be blunt or tapered.

[0399] like Figure 30D As shown, the insert preferably includes a stop portion 3006a. The stop portion 3006a facilitates proper placement of the tube 201 relative to the insert 3005. The stop portion 3006a also serves to protect the PCB assembly 3003 from direct contact with the tube 201. Figure 30E An alternative construction is shown in the diagram. Figure 30E In the middle, the stop portion 3006b is formed as a helical or spiral component such as a helical or spiral rib. This construction is advantageous because the shape compensates for the helical winding of the tube 201, thereby providing a secure connection between the insert 3005 and the tube 201.

[0400] Figure 31A and Figure 31B Another alternative construction is shown in these figures. In these figures, the stop portion 3006c is formed as a helical or spiral component, such as a helical or spiral rib. Again, this construction is advantageous because the shape is favorable for the helically wound tube 201 ( Figure 31B This provides compensation, thereby ensuring a secure connection between the insert 3005 and the tube 201. In this configuration, the stop portion 3006c includes a directional stop feature structure 3101. Figure 31B As shown, the surface of the directional stop feature 3101 is tapered, making it resemble a fish fin. The shape of the directional stop feature 3101 can clamp, grip, or otherwise retain the second elongated member 205 of the tube 201. The directional stop feature 3101 can therefore be used to better hold the tube 201 in the correct position by preventing movement and / or rotation of the tube 201.

[0401] return Figure 30E The patient end 3001 of the insert 3005 is larger than Figure 30DThe patient end of the document explains how the size can be modified for different applications (e.g., connecting to an interface for infants or adults).

[0402] Figure 30G The cross-section of connector 3000 is shown, and it generally corresponds to the... Figure 30A The same side perspective view. In some embodiments, an insulating gap, such as an air gap, exists between the tube 201 and the insert 3005 to protect the sensor (discussed above) from thermal radiation from one or more heating filaments in the tube 201, which can induce sensor error at low flow rates. Figure 30G In this configuration, such gaps will appear above and below the sensor portion 3017. Alternatively, in some embodiments, the insert 3005 is formed such that the bubble is encapsulated within the insert 3005. For example, the insert 3005 may comprise a porous plastic.

[0403] Figure 30H A cross-section of the insert assembly 3007 is shown, and generally corresponds to... Figure 30D Side perspective view. Figure 30I An alternative cross-section of the insert assembly 3007 is shown, and generally corresponds to... Figure 30E Side views. These figures show more details relating to the relative placement of tube 201, insert assembly 3007, and / or cap 3009.

[0404] like Figure 30G As shown in –30I, the generally annular catch structure 3013 includes two molded rings extending radially outward from the body of the insert 3005. The molded rings conform to a notch 3011, which includes a molded ring extending radially inward from the cap 3009. The notch 3011 and the catch structure 3013 retain the cap 3009 on the insert 3005.

[0405] Figure 32A and Figure 32B An alternative configuration of the capture structure 3013 is shown. Again, the capture structure 3013 is generally annular and includes two molded rings extending radially outward from the body of the insert 3005. A plurality of anti-rotation protrusions 3201 extend vertically between these rings. In this example, four evenly spaced protrusions 3201 (e.g., at 90° intervals) are present around the circumference of the capture structure 3013. The protrusions 3201 engage with conforming slots (not shown) in the cap and prevent the cap from rotating on the insert assembly. Figure 32C–32D shows another alternative configuration of the capture structure 3013. Again, the capture structure 3013 is generally annular and includes two molded rings extending radially outward from the body of the insert 3005. Anti-rotation slots 3203 are provided between these rings. In this example, four evenly spaced slots 3203 (e.g., at 90° intervals) are present around the circumference of the capture structure 3013. These slots 3203 engage with compliant protrusions (not shown) in the cap and prevent the cap from rotating on the insert assembly.

[0406] Figure 30G –30I further shows that: PCB assembly 3003 includes PCB 3015, sensor portion 3017, and positioning portion 3019. PCB assembly 3003 is positioned such that, in use, sensor portion 3017 is within a fluid flow path passing through 3005.

[0407] The sensor portion 3017 includes one or more sensors, such as temperature sensors. The sensors are preferably positioned on a protruding portion of the sensor portion 3017. Suitable temperature sensors include thermistors, thermocouples, resistance temperature detectors, or bimetallic thermometers.

[0408] PCB 3015 completes the heating and / or sensing circuitry for composite tube 201.

[0409] The positioning portion 3019 improves stability and helps position the PCB assembly 3003 during manufacturing. However, in some embodiments, the positioning portion 3019 may be omitted.

[0410] Figure 30I It is also shown that the PCB assembly 3003 can be further stabilized in the insert 3005 by recessing at least a portion of the PCB 3015 and / or the positioning portion 3019 on the outer surface of the insert 3005. Figure 30N The concave structure is also shown in the image.

[0411] Figure 30G The construction of –30I offers several advantages. For example, some embodiments include the following implementation: placing the sensor portion 3017 within the fluid flow path facilitates accurate measurement, regardless of flow rate, ambient temperature, etc. Furthermore, some embodiments include the following implementation: compared to a construction with a separate sensor attached to a connector, fluid leakage due to poor user setup of the circuitry is less likely to occur.

[0412] Additionally, some embodiments include the following implementation: since the PCB assembly 3003 extends across the entire width of the insert 3005, the PCB assembly 3003 can be used to allow the connecting lines to cover the entire tube 201. As described below, Figure 33A–33D illustrates the design of a PCB assembly 3301 that allows interconnects to be distributed throughout the tube, with corresponding figures showing both sides of the PCB assembly 3301. The concept of distributing interconnects throughout the tube 201 is referenced below. Figure 34 This will be further discussed in the context of the intermediate connector between the two pipe sections 201.

[0413] First go to Figure 33A and 33B The PCB assembly 3301 includes connection pads 3303 and 3305 for connecting the heating filament and / or the sensor. The connection pads 3303 and 3305 are configured to be located on opposite sides of the PCB assembly 3303 to facilitate their connection with the spirally wound heating filament.

[0414] PCB assembly 3301 includes a sensor connection pad 3307 for a sensor. The sensor can be coupled to a diode via a signal connection pad 3309 on PCB assembly 3301. As shown, PCB assembly 3301 includes a gap 3311 configured to thermally insulate the sensor from other electrical components and rails. In some embodiments, gap 3311 may be filled with an insulating material to further thermally isolate the sensor connected to sensor connection pad 3307. Furthermore, PCB assembly 3301 may be configured to position the sensor spaced apart from other active and / or passive electrical components such as protruding feature structures 3313.

[0415] PCB assembly 3301 includes a power connection pad 3315 for a diode electrically coupled to a heating filament via conductive tracks on PCB assembly 3301. The power connection pad 3315 can be electrically and thermally coupled to a heat sink 3317 to aid in heat dissipation, thereby reducing or minimizing the impact on the accuracy of temperature readings from a thermistor coupled to sensor connection pad 3307.

[0416] Figure 33C and 33D It shows Figure 33A and Figure 33B PCB assembly 2901 is located through the above-mentioned target Figure 30A –30O discussion insert 2605 or below regarding Figure 34 The appropriate position of the intermediate connector 3403 is discussed.

[0417] Therefore, in at least one embodiment, the breathing tube segment such as insert 2605 or intermediate connector 3403 includes a lumen extending along a longitudinal axis and a wall surrounding the lumen, which defines a gas flow path during use; and a PCB assembly 3301, which includes a printed circuit board and further includes a first portion extending through the lumen along a diameter or chord, such that a portion of the printed circuit board assembly substantially divides at least a portion of the flow path in two, the first portion being overmolded with an overmolding composition, and a second portion adjacent to the first portion projecting outward from the wall in a direction away from the lumen, the second portion including one or more connections on the printed circuit board. Pad 3303, the one or more connecting pads being configured to receive one or more metal wires from a first component, a third portion adjacent to the first portion projecting outward from the wall in a direction away from the lumen and in a direction opposite to the second portion, the third portion including one or more connecting pads 3305 on the printed circuit board, the one or more connecting pads being configured to receive one or more metal wires from a second component different from the first component, and one or more conductive tracks on the printed circuit board being electrically coupled to the one or more connecting pads of the second portion and the one or more connecting pads of the third portion, and being configured to provide an electrical connection between the first component and the second component.

[0418] The first component and the second component can each be a breathing tube. Alternatively, the first component can be a breathing tube, and the second component can be, for example, a patient interface.

[0419] Return again Figure 30G In the example of –30I, the sensor portion 3017 is mounted or formed such that the sensor portion 3017, PCB 3015, and positioning portion 3019 form a single unit. For example, the sensor portion 3017, PCB 3015, and positioning portion 3019 can be mounted together with each other using a suitable method such as soldering. The sensor portion 3017, PCB 3015, and positioning portion 3019 can be integrally formed from a suitable material such as a circuit board substrate.

[0420] The sensor portion 3017 can be electrically connected to the PCB 3015 using a suitable technique such as circuit printing. For example, the electrical connection may include conductive tracks such as copper tracks. To electrically connect the conductive filament in the second elongated member of the tube 201 to the connection pad of the PCB assembly 3003, the techniques described above can be used... Figure 25E –25I shows a process similar to the one described. Additional electrical components, such as diodes (not shown), can be positioned on either side of the PCB 3015, inside and / or outside the gas path. Positioning the diodes outside the gas path is discussed above with reference to sensor connection pads 3307 and 3309, and as… Figure 33A As shown in –33B.

[0421] Return again Figure 30G In the example of –30I, the PCB assembly 3003 can be mounted within the insert 3005 using, for example, an overmolding method known in the art. A material having a thermal conductivity in the range of 0.03–0.6 W / m·K or around thereon, such as polypropylene (thermal conductivity 0.1–0.22 W / m·K), can be used for at least a portion of the overmolded portion. Using a material with low thermal conductivity can advantageously reduce interference from the surrounding environment during sensor measurement because the material has a poor ability to conduct heat from the sensor portion 3017 to the wall of the insert 3005. Some embodiments include the implementation that overmolding a single PCB assembly 3003 allows for more consistent sensor placement than overmolding a single sensor. Additionally, some embodiments include the implementation that overmolding a sensor placed in the center of the tube can make the sensor less sensitive to radiation.

[0422] like Figure 30G As shown in –30I, the PCB assembly 3003 extends beyond the width of the insert 3005 and is supported by the opposing wall of the insert 3005. Because the PCB assembly 3003 is supported on the opposing side of the insert 3005, the PCB assembly 3003 can be relatively thin (i.e., having a smaller thickness and width than a PCB with a support on a tube). The thin profile can facilitate fluid flow by providing less resistance to flow than a thicker profile.

[0423] The molding coating around the sensor portion 3017 is preferably configured to reduce resistance to fluid flow around the sensor portion 3017. The molding coating may have an aerodynamically efficient conical shape, such as an airfoil shape, for example a bird wing shape, or a fully conical torpedo shape (e.g.,...). Figure 30G and Figure 30H As shown), or a portion with a blunt edge forming a conical bullet shape (such as...). Figure 30I (As shown in the diagram). These conical shapes facilitate fluid flow. Furthermore, when placed in a fluid flow, these conical shapes reduce turbulence and eddies at the trailing edge of the cone, which can cause unwanted cooling of the humidifying gas and condensation. Condensation can lead to inaccurate measurements and unwanted temperature drops in the gas delivered to the patient. Therefore, the conical shape can contribute to more accurate readings. Additionally, the conical shape can reduce the collection of condensate that has already formed by promoting outflow and also reduce the accumulation of patient secretions.

[0424] The conical shape can also be chosen to reduce turbulence by reducing the formation of eddies in the flow and to increase the likelihood that the flow will remain laminar.

[0425] The distance between the tapered shape and the inner wall of the insert 3005 is preferably chosen to allow more space. In at least one embodiment, the distance between the tapered shape and the inner wall of the insert 3005 is at least 10% (or about 10%) or at least 30% (or about 30%) of the inner diameter, such as 33% (or about 33%) or 40% (or about 40%). In at least one embodiment, the distance between the tapered shape and the inner wall of the insert 3005 is greater than 2 mm (or about 2 mm). Allowing more space reduces the likelihood of condensate being trapped in that space.

[0426] The overmolded section helps to obtain a more even temperature reading. A temperature deviation exists across the entire insert 3005, with higher temperatures towards the center and lower temperatures along the walls. This asymmetrical temperature profile, where the highest temperature deviates from the centerline of the insert 3005, is particularly prevalent for the bent tube 203. The overmolded section has a larger surface area than the sensor portion 3017 of the PCB assembly 3003, and the overmolding material disperses heat, allowing the sensor in the sensor portion 3017 to measure a more even temperature across the entire flow path.

[0427] Figure 30J An end view of connector 3000 taken along the width of the connector is shown, as viewed from the patient end portion 3001 of connector 3000 toward the tube (not shown). In this view, the overmolded tapered shape housing the PCB assembly 3003 (not shown) is generally centered. Figure 30K An alternative construction is shown. In this view, the tapered shape is offset from the center line. (As shown...) Figure 30J and Figure 30K As shown, the junction 3018 between the inner wall of the insert 3005 and the overmolded tapered shape that accommodates the PCB assembly may optionally have multiple rounded corners to reduce fluid disturbance and decrease the area of ​​fluid buildup. The rounded corners of the junction 3018 may be, for example, a radius of 1 mm (or about 1 mm).

[0428] Figure 30L Showing more details Figure 30K The offset positioning is achieved through a tapered shape. Since the sensor 3020 protrudes outward from the PCB assembly 3003, the offset configuration can improve accuracy by placing the sensor 3020 closer to the centerline. Furthermore, the offset configuration may also be desirable because the PCB assembly 3003 can be accommodated in one side of the molding tool during manufacturing, thereby simplifying the manufacturing process.

[0429] Figure 30MA longitudinal section of the insert assembly 3007 is shown, along with further details of the PCB assembly 3003. A sensor 3020 is placed in the flow path. The sensor 3020 can provide temperature and / or gas flow information, thereby allowing assessment of conditions near the patient interface. The sensor 3020 is preferably positioned close to the edge of the protruding portion of the sensor portion 3017. The thickness of the proximal molded portion of the sensor 3020 is preferably thinner than the thickness of the molded portion surrounding other portions of the PCB assembly 3003, such as... Figure 30O As shown in the diagram, reducing the thickness of the overmolding improves heat transfer to facilitate more accurate temperature measurements.

[0430] Refer again Figure 30M Conductive track 3021 electrically connects sensor 3020 to PCB 3015. (Note that...) Figure 30M Sensor 3020 is not specifically shown; instead, the structure labeled 3020 indicates the general location of the sensor. The structure labeled 3020 shows the two conductive pads that the sensor will bridge. (For illustrative purposes, this structure is labeled sensor.) Through-hole 3023 allows the component to contact the desired conductive layer. Figure 30N An alternative construction of PCB assembly 3003 is shown. Figure 30N In this design, the conductive track 3021 has a skewed path. It has been recognized that increasing the length of the conductive track 3021 within the flow path allows the temperature of the conductive track 3021 to more accurately reflect the temperature within the flow path, thereby reducing the influence of the environment on the sensor 3020 through the conductive track 3021. Preferably, there is an increased copper surface area near the sensor 3020. The increased copper area contributes to accurate temperature detection around the region of the sensor 3020.

[0431] In some embodiments, the tapered shape may extend upstream along the gas path toward the source of the gas flow. This configuration facilitates more accurate measurements by ensuring that the sensor 3020 protrudes into the fluid flow as it passes through the encapsulation molding section before the fluid cools. This configuration also facilitates more accurate measurements by reducing the "stem effect." All contact-type temperature sensors exhibit a stem effect. When the probe is immersed in the fluid flow, a heat conduction path is created through the probe's stem. When the ambient temperature is cooler than the temperature of the fluid flow being measured, heat is conducted away from the probe tip via the probe's stem to the outside atmosphere. This results in the sensing tip reading a lower temperature than the actual surrounding fluid. Conversely, when the ambient temperature is warmer than the temperature of the fluid flow being measured, heat is conducted from the outside atmosphere toward the probe tip via the probe's stem. This results in the sensing tip reading a higher temperature than the actual surrounding fluid. The tapered shape reduces the stem effect by making the sensor 3020 protrude away from the portion of the sensor portion 3017 that connects the PCB 3015 and the positioning portion 3019 (i.e., away from the "stem"). In some embodiments, the tapered shape extends upstream by at least 6 mm (or about 6 mm) from the portion of the sensor portion 3017 that connects the PCB 3015 and the positioning portion 3019.

[0432] In some embodiments, the tapered shape may extend downstream away from the source of the gas flow. This configuration, for example in the design of the overmolded PCB assembly 3003, significantly alters the average downstream fluid characteristics, making it advantageous when it is desirable to accurately measure the fluid characteristics leaving the tube.

[0433] The heating filament (not shown here but described above) in the second elongated member can be connected to PCB 3015, which provides termination points to complete the heating filament circuitry. PCB 3015 can also be used to provide additional termination points to power a separate heating filament in a secondary tube, such as in a segmented intake manifold configuration used with a humidification system, having connectors configured to couple the heating filaments in two sections to the sensor. (See above reference) Figure 33A –33D describes a suitable PCB component construction.

[0434] Return again Figure 30MThis configuration eliminates the need for a separate power line extending to the heating filament. This configuration further ensures that the heating filament extends along tube 203 and terminates at approximately the same location on tube 203 as the sensor 3020. Therefore, this configuration minimizes the temperature drop from the end of the heating filament to the sensor 3020. This configuration also reduces the temperature drop from the end of the heating filament to a second heating filament in another segment of the tube. This configuration can also be used for the cover connector of the heated sensor 3020, thereby reducing heat loss to the cold environment and further improving the accuracy of temperature measurement.

[0435] Although the foregoing describes placing one or more sensors at the patient end of tube 201, it should be understood that this sensor configuration can be applied along any part of the fluid path of tube 201.

[0436] For example, Figure 34 A portion of a segmented inhalation liner 3401 for use with a breathing humidification system is shown. The segmented inhalation liner 3401 includes a first segment 3401a and a second segment 3401b, and has an intermediate connector 3403 configured to couple a first heating wire 3405a to a second heating wire 3405b and a first temperature sensor 3407a to a second temperature sensor 3407b in the corresponding segments 3401a and 3401b. Coupling the two segments 3401a and 3401b may include mechanically joining these segments to form a single conduit through which humidifying gas can be delivered to the user, wherein the mechanically joined segments 3401a and 3401b can electrically couple the corresponding heating wires 3405a and 3405b and the corresponding temperature sensors 3407a and 3407b via the intermediate connector 3403. Figure 33A and Figure 33B The PCB assembly 3301 shown is adapted to be with Figure 34 It is used together with the intermediate connector 3403.

[0437] Return again Figure 34The segmented intake manifold 3401 may include a structure 3409 forming a cavity through which humidifying gas can pass. Structure 3409 may include paths formed within its walls, configured to accommodate heating wires 3405a or 3405b, such that the heating wires 3405a or 3405b are protected from the influence of humidifying gas traveling through the cavity and / or covered by an outer surface of structure 3409, thus preventing exposure. For example, structure 3409 may be a composite tube, wherein the heating wire paths are coils molded into the tube as described above. Structure 3409 may contain any type of suitable material and may include insulating and / or flexible materials. In some embodiments, structure 3409 and intermediate connector 3403 may be configured such that when the first segment 3401a and the second segment 3401b are mechanically connected, heating wires 3405a and 3405b are wrapped around the intermediate connector 3403 in a manner to electrically couple to the intermediate connector 3403. In some embodiments, the first segment 3401a and / or the intermediate connector 3403 may exclude any flying leads for connection to the second segment 3401b, thereby facilitating connection of the second segment 3401b to the first segment 3401a.

[0438] Structure 3409 at the complementary ends of the first segment 3401a and the second segment 3401b can be configured to accommodate an intermediate connector 3403. Therefore, the intermediate connector 3403 can be inside the inspiratory branch 3401. In some embodiments, the complementary ends of the first segment 3401a and the second segment 3401b can be configured to protect the intermediate connector 3403 from the influence of humidifying gas traveling through the inspiratory branch 3401. In some embodiments, the intermediate connector 3403 is inside the inspiratory branch 3401 and protected from the influence of humidifying gas in the conduit, thereby reducing or eliminating exposure of electrical connections on the intermediate connector 3403.

[0439] In some embodiments, the first heating wire 3405a may include two metal wires 3411 and 3413, and the second heating wire 3405b may include two metal wires 3415 and 3417. The two metal wires 3411 and 3413 in the first segment 3401a may be electrically coupled to each other via an electrical component 3419, wherein the electrical coupling creates an electrical path through the metal wire 3411, at least a portion of the electrical component 3419, and the metal wire 3413. Similarly, the two metal wires 3415 and 3417 in the second segment 3401b may be electrically coupled to each other via an electrical component 3419, and / or electrically short-circuited together at one end of segment 3401b opposite to the intermediate connector 3401b, such as via a patient-end connector (not shown). By coupling the wires 3415 and 3417 of the second segment 3401b at the intermediate connector 3403, the electrical connection at the patient end of the inspiratory bronchus 3401 is reduced or eliminated, which can reduce cost, system complexity and / or patient risk.

[0440] Intermediate connector 3403 can be configured to allow a single controller, such as a humidifier controller, to control the power supplied to heating wires 3405a and 3405b. In some embodiments, the humidifier controller controls the heating wires 3405a and 3405b, and no additional control functions exist on the intermediate connector 3403. For example, intermediate connector 3403 may include passive components without any logic circuitry, wherein the passive components direct power to heating wires 3405a and / or 3405b according to the controller's selection. This allows for the use of relatively inexpensive components in the design of intermediate connector 3403 and reduces design complexity.

[0441] In some embodiments, heating of the two sections 3401a and 3401b can be accomplished using a maximum of four metal wires in each section 3401a, 3401b. For example, in the first section 3401a, the four metal wires may include a first heating wire 3411, a second heating wire 3413, a signal temperature sensing wire 3419, and a return temperature sensing wire 3421. In the second section 3401b, the four metal wires may include a first heating wire 3415, a second heating wire 3417, a signal temperature sensing wire 3423, and a return temperature sensing wire 3425. By coupling the second heating wires 3415 and 3417 to the first heating wires 3411 and 3413 at connection point 3427, and by coupling the second temperature sensing wires 3423 and 3425 to the first temperature sensing wires 3419 and 3421 at connection point 3427, the controller can be configured to independently supply power to the first heating wire 3405a and the second heating wire 3405b, and independently read temperature sensor data from temperature sensors 204a and 204b, without having to include more than four metal wires in either segment 3401a or 3401b. In some embodiments, the control of heating wires 3405a and 3405b and the reading of temperature sensors 3407a and 3407b can be accomplished using fewer than four wires in each segment (e.g., using three or two wires) or more than four wires in each segment (e.g., using five, six, seven, eight, or more than eight wires).

[0442] The intermediate connector 3403 may include electrical components 3419 configured to allow a controller to selectively control heating wires 3405a and 3405b. The controller may be configured to control the heating of the inspiratory branch 3401 using two modes, wherein a first control mode includes supplying power to heating wire 3405a in the first segment, and a second control mode includes supplying power to heating wires 3405a and 3405b in both the first and second segments 3401a and 3401b. Therefore, the controller may be configured to control the heating wire segments independently. This capability allows the controller to control the heating of the inspiratory branch 3401 by controlling only the heating of the inspiratory branch according to the first control mode when the second segment 3401b is absent, thereby allowing the respiratory humidification system to be used in various situations without requiring modification to the controller or humidification device. In some embodiments, these control modes may include a mode that supplies power only to heating wire 3405b in the second segment 3401b. In some embodiments, the controller includes a power source that provides current. The first and second control modes can be at least partially based on the voltage supplied by the power source, wherein a positive voltage or positive current can trigger the first control mode, and a negative voltage or negative current can trigger the second control mode. In some embodiments, the power source provides rectified AC or DC power to the heating wires 3405a, 3405b, and a change in rectification or polarity triggers a change in the control mode. By switching control modes, the control of heating in the breathing circuit can be accomplished using any power source capable of switching the polarity of the output signal. In some embodiments, the amount of power supplied to the heating wires 3405a, 3405b can be adjusted by regulating the duty cycle of the power applied to the heating wires 3405a, 3405b. For example, pulse-width modulation (PWM) can be used to activate the heating wires 3405a, 3405b, and the duty cycle of the PWM signal can be adjusted to control the delivered power. In another instance, the amount of power supplied to the heating wires 3405a, 3405b can be adjusted by controlling the amplitude of the power signal.

[0443] Intermediate connector 3403 may include electrical components 3421 configured to allow the controller to selectively read temperature sensors 3407a, 3407b. Selective reading can be accomplished using a current source, wherein applying a positive current to the wires 3419 and 3421 as a whole causes the controller to measure a temperature-related signal from the first temperature sensor 3407a, and applying a negative current to the wires 3419 and 3421 as a whole causes the controller to measure a temperature-related signal from the second temperature sensor 3407b, or from both the first and second temperature sensors 3407b. The controller can use the readings from the temperature sensors 3407a, 3407b to adjust the power supplied to the heating wires 3405a, 3405b using, for example, pulse-width modulation. A first temperature sensor 3407a can be positioned near the junction or intersection of the first section 3401a and the second section 3401b to provide the controller with the temperature of the gas entering the second section 3401b, which may correspond to entry into an incubator or other such area with a different ambient temperature. A second temperature sensor 3407b can be positioned at the patient end of the second section 3401b to provide the controller with the temperature of the gas delivered to the patient, or the temperature before the final workpiece, such as a Y-shaped workpiece, preceding the patient. The controller can use these temperature readings to adjust the power supplied to the heating wires 3405a, 3405b to maintain the temperature of the gas at the patient end of the inspiratory manifold 3401 at a target or suitable temperature. The target or suitable temperature can vary at least in part depending on the application and environment in which it is used, and can be about 37°C, about 40°C, at least about 37°C and / or less than or equal to about 38°C, at least about 36.5°C and / or less than or equal to about 38.5°C, at least about 36°C and / or less than or equal to about 39°C, at least about 35°C and / or less than or equal to about 40°C, at least about 37°C and / or less than or equal to about 41°C, or at least about 39.5°C and / or less than or equal to about 40.5°C. In some embodiments, the second temperature sensor 3407b can be positioned inside the incubator but not attached to the breathing circuit. The temperature of the second segment 3401b can be calculated by measuring the temperature inside the incubator.

[0444] The controller can independently control the amount of power delivered in the first and second control modes as described herein. Based at least in part on feedback from temperature sensors 3407a and / or 3407b, the controller can independently adjust the power delivered in the first and second control modes, thereby causing a change in the heater power ratio between the first segment 3401a and the second segment 3401b.

[0445] In some embodiments, the first temperature sensor 3407a is positioned within the gas flow within the intake manifold 3401. In some embodiments, the intermediate connector 3403 or the first segment 3401a may include mechanical components that reduce turbulence in the gas flow passing through the first temperature sensor 3407a, which can improve the accuracy of the temperature sensor 3407a readings. In some embodiments, the turbulence-reducing mechanical components (e.g., cross-shaped member features within the intake manifold) also secure the temperature sensor 3407a within the gas flow. In some embodiments, the intermediate connector 3403 and the mechanical components are configured to thermally isolate the temperature sensor 3407a from electrical components on the intermediate connector 3403.

[0446] In some embodiments, the intermediate connector 3403 includes, in addition to Figure 34 Other connection points besides connection point 3427 shown. These additional connection points can be used to integrate additional functions into the breathing circuit, such as integrating a memory device (PROM), a microcontroller, other circuits, etc.

[0447] In addition, the composite tube 201 can be an inhalation tube or an exhalation tube.

[0448] Placement of spiral connectors

[0449] Next reference Figure 35A –35E, these figures show a connector not electrically connected to the PCB. However, as those skilled in the art will appreciate, this connector can be equivalently adapted to have an electrical connection to the PCB. This connector is suitable for connection to, for example, a patient interface or a humidifier. It is particularly suitable for use as a patient-end connector and / or device-end connector in obstructive sleep apnea environments.

[0450] A molded insert 3501 with a spiral termination is provided. The end of the insert 3501 opposite the spiral end is molded for insertion into or attachment to a humidifier port, and / or a patient interface port, and / or any other desired component. The insert 3501 may be a rigid material such as a hard plastic, for example, polypropylene.

[0451] like Figure 35C As shown, the helical end of the insert 3501 is screwed onto the conforming ring of the tube 201. In this example, the size and configuration of the helical rings of the insert 3501 are matched to those rings of the first elongation member 203 of the tube 201.

[0452] It should be noted that if a tube has one or more electrodynamic metal wires, an electrical connection can be provided on at least a portion of the insert 3501. When installing the insert 3501, it is preferable to align the electrical connector with these wires to facilitate the electrical connection. The connection can then be secured using solder or the like.

[0453] A member 3503 may be inserted into or molded on top of the insert 3501 and optionally at least a portion of the tube 201 to facilitate attachment between the insert 3501 and the tube 201. The member 3503 may be a rigid material or a soft material, such as soft plastic, rubber, or PTFE, for example, polypropylene. In some cases, the insert 3501 (or at least the helical end of the insert 3501) provides sufficient lateral resistance to compression to enable high-pressure molding techniques, where pressures can exceed the lateral resistance to compression of the tube 201 without the insert 3501. The member 3503 may also advantageously provide a soft surface for gripping when inserting or removing the tube from the component.

[0454] The aforementioned method for attaching a connector to a spirally wound tube is provided by way of example. The method described herein does not imply a fixed order for the steps, nor does it imply that any single step is required to perform the method. The embodiments can be practiced in any order, and combinations thereof are also possible.

[0455] Placement of alternative patient-end connectors

[0456] Next reference Figure 36A -36K. Figure 36A and Figure 36B A patient-end connector 3601 without electrical connection is shown. Connector 3601 has a patient end 3603 with a standard-sized medical taper suitable for use with a patient interface. The tubular end 3605 of connector 3601 is adapted to connect to composite tubing 201 as described below. Connector 3601 is preferably a pre-molded component formed from a suitable material such as plastic, rubber, or PTFE.

[0457] like Figure 36C and Figure 36D As shown, a portion of the second elongated member 205 (e.g., a 10-mm portion) is peeled off to expose one or more shorter filaments 215 embedded therein. Preferably, filaments 215 of about 5 mm or 10 mm are exposed. Figure 36D As shown, the filaments 215 are twisted together and optionally secured, for example, by welding, to create a closed-loop circuit.

[0458] Then turn to Figure 36GThe tube end 3605 of connector 3601 is inserted into tube 201, and twisted filament 215 is positioned below retaining ring 3607. Retaining ring 3607 reduces movement of filament 215 during molding. Retaining ring 3607 also advantageously aligns the rotational pitch of composite tube 201 with connector 3601, which in turn promotes proper alignment of tube 201 in the mold. The combination of connector 3601 and composite tube 201 is here designated as connector-tube assembly 3609.

[0459] like Figure 36H As shown, the molding tool core 3611 is inserted into the connector 3601. Figure 36I As shown, the connector-tube assembly 3609 and the core 3611 are placed in the injection molding tool 3613. Figure 36J In this process, a molding material 3615 is molded onto the mating area between the composite tube 201 and the connector 3601, thereby joining the composite tube 201 and the connector 3601. Suitable molding materials 3615 include plastics and rubbers. The connector-tube assembly 3609 and the core 3611 are removed from an injection molding tool (not shown), as follows: Figure 36K As shown in the diagram, the core 3611 is removed, thereby providing the patient-end connector 3601 to the composite tube 201.

[0460] The aforementioned method for attaching a connector to a composite pipe is provided by way of example. The described method does not imply a fixed order for the steps, nor does it imply that any single step is required to perform the method. The embodiments can be performed in any order, and combinations thereof are also possible.

[0461] The foregoing description of the invention includes preferred forms. Modifications may be made to the invention without departing from its scope. The numerous structural changes, distinct embodiments, and applications of the invention will be apparent to those skilled in the art as they themselves do not depart from the scope of the invention as defined in the appended claims. The disclosure and description herein are entirely illustrative and not intended to be limiting in any sense.

[0462] Throughout this specification and claims, the terms “comprises”, “comprising”, etc., shall be interpreted as including, that is, “including but not limited to”, unless the context clearly requires otherwise.

[0463] Although the invention has been described by way of example and with reference to its possible embodiments, it should be understood that various modifications or improvements can be made thereto without departing from the spirit and scope of the invention and without diminishing its additional advantages. Furthermore, where reference has been made to specific parts or the whole of the invention having known equivalents, these equivalents are incorporated herein as if they were presented separately.

[0464] Any discussion of the prior art throughout this specification should not be construed as an admission that the prior art is widely known or part of common knowledge in the art, formed anywhere in the world.

Claims

1. A breathing tube for delivering humidified gas to a patient, the breathing tube comprising: A first connector at a first end of the tube and a second connector at a second end of the tube opposite to the first end; A lumen extending between the first end and the second end, and the lumen being configured to define a gas flow path during use; A conductive filament is spirally wound along the length of the tube and is embedded or encapsulated in the wall of the tube. A printed circuit board assembly, which is fixed to the wall of the first connector, the printed circuit board assembly comprising: A first wiring portion includes a first connecting pad configured to be electrically connected to the conductive filament, the first wiring portion being fixed to the wall of the first connector; A segment extending through the lumen along a diameter or chord line to substantially divide at least a portion of the gas flow path in two, and the segment includes a sensor portion located within the gas flow path and including at least one temperature sensor. The second wiring portion includes a second connecting pad configured to be electrically connected to the conductive filament, the second wiring portion being fixed to the wall of the first connector, the first connecting pad and the second connecting pad being spaced apart and disposed on opposite sides of the printed circuit board assembly; One or more conductive tracks are configured to electrically connect the at least one temperature sensor to the first connection pad of the first wiring portion; and At least one diode is disposed on the printed circuit board assembly, and The printed circuit board assembly is configured to position the at least one temperature sensor spaced apart from other active and / or passive electrical components.

2. The breathing tube according to claim 1, wherein, The printed circuit board assembly is configured to separate the at least one temperature sensor and the at least one diode by including a gap.

3. The breathing tube according to claim 1, wherein, The at least one temperature sensor is located near the edge of the sensor portion and is configured to assess conditions near the patient interface.

4. The breathing tube according to claim 1, wherein, The printed circuit board assembly is overmolded from an overmolding composition.

5. The breathing tube according to claim 4, wherein, The printed circuit board assembly is integrally formed and is overmolded by the overmolding composition.

6. The breathing tube of claim 1, further comprising an overlay molding composition disposed at least above the segmented portion, the sensor portion, and the at least one diode.

7. The breathing tube according to claim 4, 5 or 6, wherein, The overmolding composition has a thermal conductivity in the range of 0.03 to 0.6 W / m·K.

8. The breathing tube according to claim 1, wherein, The at least one temperature sensor is located on the surface of the sensor portion.

9. The breathing tube according to claim 1, wherein, The conductive filament includes a heating filament, which is connected to the second connection pad of the second wiring portion.

10. The breathing tube according to claim 9, wherein, The heating filament terminates on the tube at a position approximately the same as that of the at least one temperature sensor.

11. The breathing tube according to claim 1, wherein, The one or more conductive tracks have distorted paths.

12. The breathing tube according to claim 1, wherein, The thinnest portion of the overmolded composition is near the edge of the sensor portion.

13. The breathing tube according to claim 1, wherein, The at least one temperature sensor is a thermistor.

14. The breathing tube according to claim 1, wherein, The conductive filaments include heating filaments and / or sensing filaments.

15. The breathing tube according to claim 14, wherein, The printed circuit board assembly completes: a heating circuit of the tube formed by the heating wire; and / or a sensing circuit of the tube formed by the sensing wire.

16. The breathing tube according to claim 14, wherein, The printed circuit board assembly is configured such that the first connecting pad of the first wiring portion and / or the second connecting pad of the second wiring portion are positioned outside the gas flow path.

17. The breathing tube of claim 1, comprising an elongated body defining the lumen and in fluid communication with the first connector and the second connector, such that the first connector, the second connector and the elongated body, in use, form the gas flow path for the humidifying gas located between the first end and the second end.

18. The breathing tube according to claim 17, wherein, The elongated body includes a smooth lumen surface.

19. The breathing tube according to claim 17, wherein, The elongated body includes a helically wound hollow body and a reinforcing portion disposed between adjacent coils of the hollow body.

20. The breathing tube according to claim 1, wherein, The second connector is configured to removably connect the breathing tube to a breathing aid or humidifier during use, forming a pneumatic and electric connection.

21. The breathing tube according to claim 20, wherein, The second connector includes a plug configured to connect to the breathing aid or humidifier.

22. The breathing tube according to claim 1, wherein, The second connector is configured to removably connect the breathing tube to the CPAP device during use, wherein the conductive filament terminates at least two electrical conductors of the second connector.

23. The breathing tube according to claim 22, wherein, When the second connector is coupled to a breathing assist device or a humidifier, the electrical connector of the second connector electrically couples the at least one temperature sensor to at least one controller of the breathing assist device or the humidifier.

24. The breathing tube according to claim 1, wherein, The first connector is configured to pneumatically connect the tubing to the patient interface at least during use.

25. The breathing tube according to claim 1, wherein, The conductive filament is connected to the first and second connection pads of the printed circuit board assembly of the second connector, which is to be connected to the at least one temperature sensor current, and the first connector.

26. The breathing tube according to claim 1, wherein, The breathing tube is an inspiratory duct.

27. A printed circuit board assembly configured to be fixed to the wall of a connector of a breathing tube having a longitudinal axis, the printed circuit board assembly comprising: A first wiring portion includes a first connecting pad configured to be electrically connected to a conductive filament of the tube, the first wiring portion being fixed to the wall of the connector; A segment extending through the lumen along a diameter or chord line and including a sensor portion located within the gas flow path and including at least one temperature sensor; The second wiring portion includes a second connecting pad configured to be electrically connected to the conductive filament of the tube, the second wiring portion being fixed to the wall of the connector, the first connecting pad and the second connecting pad being spaced apart and disposed on opposite sides of the printed circuit board assembly; One or more conductive tracks are configured to electrically connect at least one temperature sensor to the first connection pad of the first wiring portion; and At least one diode is disposed on the printed circuit board assembly, and The printed circuit board assembly is configured to position the at least one temperature sensor spaced apart from other active and / or passive electrical components.

28. The printed circuit board assembly of claim 27, wherein, The at least one temperature sensor is located near the edge of the sensor portion and is configured to assess conditions near the patient interface.

29. The printed circuit board assembly of claim 27, wherein, The at least one temperature sensor is a thermistor.

30. The printed circuit board assembly of claim 27, wherein, The one or more conductive tracks have distorted paths.

31. The printed circuit board assembly of claim 27, further comprising an overmolding composition configured at least over the segmented portion, the sensor portion, and the at least one diode.

32. The printed circuit board assembly of claim 31, wherein, The thinnest portion of the overmolded composition is near the edge of the sensor portion.

33. The printed circuit board assembly of claim 27, wherein, The printed circuit board assembly is integrally formed and is overmolded from an overmolding composition.

34. The printed circuit board assembly of claim 27, wherein, The at least one temperature sensor is positioned such that it is spaced apart by a gap and the at least one diode.

35. The printed circuit board assembly of claim 29, wherein, The overmolding composition has a thermal conductivity in the range of 0.03 to 0.6 W / m·K.

36. The printed circuit board assembly of claim 27, wherein, The at least one temperature sensor is located on the surface of the sensor portion.

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