Humidifier

Abstract

To provide a humidifier comprising a heating apparatus for use in a respiratory therapy apparatus.SOLUTION: A heating apparatus (36) includes: a heating element which converts electrical power to heat energy; a heatable element having a first surface and a second surface; and a dielectric laminate layer between the heating element and the first surface of the heatable element, where the dielectric laminate layer is thermally conductive to transfer heat energy from the heating element to the heatable element, and where the second surface of the heatable element is configured to heat a liquid in a container.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] Cross - reference to Applications This application claims the benefit of Australian Provisional Application No. 2011902350, filed on Jun. 16, 2011, and U.S. Provisional Application No. 61 / 628,622, filed on Nov. 3, 2011. Each of the above - mentioned applications is hereby incorporated by reference in its entirety into this specification.

[0002] The present invention relates to an electric heater, and more particularly to a heater used for heating a fluid in a container. More specifically, the present invention relates to an electric heater used for humidification, such as humidification of breathable gas, a device including such an electric heater, and a method of using such an electric heater. The electric heater can be used in the range of devices including all forms of respiratory ventilation systems, including invasive and non - invasive ventilation, continuous positive airway pressure (CPAP), and bilevel therapy and treatment for sleep - disordered breathing (SDB) conditions such as obstructive sleep apnea (OSA), and for various other respiratory disorders and diseases.

Background Art

[0003] Respirators generally have the ability to modify the moisture of breathable gas and reduce dryness of the patient's airway, and the resulting patient discomfort and related complications. The use of a humidifier installed between a flow generator and a patient's mask generates humidified gas, which minimizes drying of the nasal mucosa and improves the comfort of the patient's airway. In colder climates, warm air added to the mask and overall to the facial area around the mask may be more comfortable than adding cold air.

[0004] A number of humidifier types are available, including those configured to be integrated with or connected to a related breathing apparatus. Passive, unheated humidifiers can be somewhat comfortable, but heated humidifiers generally provide higher humidity and temperature to the air, increasing patient comfort. Heated humidifiers typically include a water tub having a capacity to hold several hundred milliliters of water, a heating assembly for heating the water in the tub, a control system that enables changing the level of humidification, a gas inlet that receives gas from a flow generator, and a gas outlet adapted to be connected to a patient conduit that delivers the humidified pressurized gas to a patient's mask.

[0005] Known heating assemblies may be suitable for their intended purpose, but are complex, costly, and require a manual and intensive manufacturing process. Patent Document 1 describes an exemplary electric heating plate structure.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] One aspect of the present invention relates to a heated humidifier for use in a respiratory therapy device.

[0008] Another aspect of the technology of the present invention relates to a heating device or heating assembly for a respiratory therapy device, which includes a heating element and a hot plate. The heating element and the hot plate are separated by a separating element, which has high thermal conductivity and high electrical insulation, for example, low electrical conductivity. In an example, the separating element has a predetermined form suitable for printing onto the heating element, for example, a suitable substrate. The hot plate is capable of heating water in a container included in the respiratory therapy device.

[0009] Another aspect of the technology of the present invention relates to a heating device for a respiratory therapy device, the heating device including a heating element and a hot plate, the heating element and the hot plate being spaced apart by a layer that electrically insulates the heating element and the hot plate, the heating device enabling heat transfer between the heating element and the hot plate.

[0010] In an example, the heating device includes a laminate of (i) a thermally conductive material, such as a hot plate, a metal plate, a thermally conductive substrate layer, (ii) a thermally conductive dielectric laminate layer, (iii) a heating element, and (iv) a protective layer. The dielectric laminate layer provides electrical insulation between the heating element and the hot plate, for example, avoiding an electrical short circuit between currents flowing through the heating element and the hot plate. The heating element can be printed on the laminate layer or otherwise applied to the laminate layer by conventional printing techniques used in printed circuit board (PCB) manufacturing and assembly. Alternatively, the heating element can be applied as a sheet to the laminate layer and to a portion of the sheet that is etched to form the tracks of the heating element. The heating element can be a narrow strip of conductive material (e.g., copper foil) arranged in a serpentine pattern. The thickness of the heating element and the arrangement of the serpentine pattern can be selected based on various design considerations, such as the shape of the bottom of the humidifier tab and the amount of thermal energy to be transferred to the humidifier tab.

[0011] Another aspect of the present invention technology relates to a heating device, the heating device including a heating element that converts electrical power into thermal energy, a heatable element having a first surface and a second surface, and a dielectric laminate layer between the heating element and the first surface of the heatable element, the dielectric laminate layer being thermally conductive to transfer thermal energy from the heating element to the heatable element, and the second surface of the heatable element being configured to heat a liquid in a container.

[0012] In an example, the protective layer can cover the outer surface of the heating element and the outer surface of the dielectric laminate layer. The protective layer can extend to cover the peripheral edges of the heating element and the dielectric laminate layer and can extend over the peripheral portion of the first surface of the heatable element that extends beyond the heating element and the dielectric laminate layer.

[0013] In an example, the dielectric laminate layer can be a thin layer containing at least one of polytetrafluoroethylene such as Teflon (registered trademark), polyimide, boron nitride, alumina, beryllium oxide, aluminum nitride, boron nitride, epoxy composite, and reinforced glass fiber. The thickness of the dielectric laminate layer can be in the range of about 20 μm to 160 μm, for example, 60 to 120 μm. The dielectric substrate can be suitable for withstanding voltages exceeding about 2 kV. The heatable element can include a plate made of a conductive metal, and the first and second surfaces are the opposing surfaces of the plate. The heatable element can be a printed circuit board (PCB) made of metal, and the heating element can include conductive metal foil tracks disposed on the PCB.

[0014] In an example, the heating element can include a conductive metal foil, such as a copper foil, disposed in a meandering pattern on the dielectric laminate layer. The heating element can have a direct current (DC) resistance in the range of about 5 ohms to 25 ohms at room temperature, for example, 5 to 15 ohms. The thickness of each track of the heating element can be in the range of about 0.4 mm to 1 mm, for example.

[0015] Another aspect of the technology of the present invention relates to a printed circuit board heater, which includes a heating element track layer, a thermally conductive dielectric layer, a first surface adapted to transfer heat into a container, and a substrate board having a second surface, where the second surface is on the opposite side of the first surface, and on the second surface, the thermally conductive dielectric layer is sandwiched between the board and the track layer. The printed circuit board heater also includes electrical current terminals provided on the track layer, which enable the application of electrical energy to the heating element track layer to generate resistive heating of the track layer. The thermal energy from the track layer is transferred to the substrate board through the thermally conductive dielectric layer, and the substrate board transfers the thermal energy to the container. The substrate board can include a metal board or other printed circuit type boards, for example, forming a thermally conductive board.

[0016] Another aspect of the technology of the present invention relates to a method of forming a heating device, which includes providing a metal plate having a first surface adapted to heat a liquid in a container, applying a thermally conductive dielectric layer to a second surface of the metal plate, where the second surface is on the opposite side of the first surface, and applying a heating element layer to the thermally conductive dielectric layer such that the thermally conductive dielectric layer is sandwiched between the second surface of the metal plate and the heating element layer.

[0017] Another aspect of the technology of the present invention relates to a humidifier, which includes a tab adapted to hold a predetermined amount of liquid and a heating device including a PCB type substrate. In an example, the substrate can include a metal layer, a copper layer, and a dielectric laminate layer between the metal layer and the copper layer. The metal layer can be made of aluminum, stainless steel, other thermally conductive metals, or other types of PCB substrates. The dielectric laminate layer can be made of a ceramic material or a polymer material. The heating track can be etched into a copper or a heating alloy layer. The protective layer can be printed at least on the copper layer.

[0018] In an example, the heating device is provided in a humidifier chamber adapted to receive the tab. In another example, the heating device is integral with the tab.

[0019] Another aspect of the technology of the present invention relates to a humidifier, comprising a tab adapted to hold a liquid and a heating device. The heating device includes a metal hot plate, a heating element for providing heat to heat the liquid, which is copper, a heating alloy, or a positive temperature coefficient (PTC) heating track (for example, the heating track can be etched or otherwise provided in a layer of copper, a heating alloy, or a PTC material, for example, to form a PTC layer), or a combination thereof, and a thermally conductive laminate layer between the hot plate and the heating element, which is composed of, for example, a ceramic material, a polymer material, or a mixture of ceramic and polymer materials, and a printed protection layer for covering at least the heating track.

[0020] Another aspect of the technology of the present invention relates to a humidifier, which includes a tab adapted to hold a liquid and a heating device including a thermally conductive hot plate, a heating element, a thermally conductive laminate layer between the hot plate and the heating element, and a protection layer for covering at least the heating element. The heating element includes copper or an alloy or a PTC heating track, or a combination thereof, and is capable of providing heat to heat the liquid.

[0021] Another aspect of the technology of the present invention relates to a humidifier, which includes a tab adapted to hold a liquid and a heating device including a thermally conductive hot plate, a heating element, a thermally conductive laminate layer between the hot plate and the heating element, and a protection layer for covering at least the heating element. The laminate layer is a dielectric laminate layer composed of a ceramic material, a polymer material, or a polymer mixture material.

[0022] Another aspect of the technology of the present invention relates to a humidifier, the humidifier including a tab adapted to hold a liquid, and a heating device including a thermally conductive hot plate, a heating element, a thermally conductive laminate layer between the hot plate and the heating element, and a protective layer for covering at least the heating element. The protective layer is printed, or spread, or formed on at least the heating element.

[0023] Another aspect of the technology of the present invention relates to a process for creating a heating device for a humidifier including a tab for holding a liquid, the process including providing a substrate having a first side adapted to be in thermal contact with the liquid and a second side, etching a heating track on the second side of the substrate, and applying a protective layer to the second side of the substrate to cover at least the heating track.

[0024] Another aspect of the technology of the present invention relates to a humidifier, the humidifier including a tab adapted to hold a liquid and a heating device, the heating device including a heating element having a first side and a second side, the heating element including a heating track, a first thermally conductive laminate layer provided on the first side of the heating element, and a second thermally conductive laminate layer provided on the second side of the heating element.

[0025] Another aspect of the technology of the present invention relates to a humidifier, the humidifier including a tab having an inner portion adapted to hold a liquid, a heating device including a thermally conductive hot plate and a heating element provided on a first side of the hot plate, and an overmold formed on the inner portion of the tab, the overmold completely surrounding the heating device such that the heating device is embedded in the overmold. The thermally conductive hot plate can be formed from a metallic material such as aluminum, stainless steel, or other thermally conductive metals, or a thermally conductive plastic.

[0026] Another aspect of the technology of the present invention relates to a humidifier, which includes a tab having an inner portion adapted to hold a liquid and a heating device. The heating device includes a support substrate, a heating element provided on a first side of the support substrate. The support substrate is distal to the inner portion of the tab, and the heating element is proximal to the inner portion of the tab, and includes a first thermally conductive protective layer provided on the heating element.

[0027] Other aspects, features, and advantages of the present technology will become apparent from the following detailed description when used in conjunction with the accompanying drawings, which are a part of the present disclosure and illustrate, by way of example, the principles of the present technology.

[0028] The accompanying drawings facilitate the understanding of various examples of the present technology.

Brief Description of the Drawings

[0029]

Figure 1

Figure 2A

Figure 2B

Figure 3

Figure 4-1

Figure 4-2

Figure 5

Figure 6

Figure 7

Figure 8-1

Figure 8-1A

Figure 9-1

Figure 9-2

Figure 10

Figure 11

Figure 12-1

Figure 12-2

Figure 13

Figure 14A

Figure 14B

Figure 15-1

Figure 15-2

Embodiments for Carrying Out the Invention

[0030] The following description is provided in relation to several examples that may have common characteristics and features, most of which are illustrated and some of which may not be illustrated. It should be understood that one or more features of any one example may be combined with one or more features of other examples. Additionally, any single feature, or combination of features within any one or more examples, may be capable of constituting patentable subject matter.

[0031] In this specification, the phrase "comprising" is to be understood in its "open" sense, i.e., the meaning of "including", and thus is not limited to its "closed" sense, i.e., the meaning of "consisting only of". The corresponding meaning will result from the corresponding phrases "comprise", "comprised", and "comprises" where they appear.

[0032] The term "air" is to be considered to include breathable gas, e.g., air with oxygen supplementation.

[0033] Respirator Figure 1 shows a respirator 10 including a flow generator 12 and a humidifier 14. The humidifier 14 includes a humidifier chamber 16 and a lid 18 for the chamber. The lid is movable, e.g., pivotable between an open position and a closed position. The water chamber, or humidifier tab 20, is seated within the humidifier chamber 16 or otherwise provided and is covered by the lid 18 when the lid 18 is in the closed position. In another example, the humidification chamber may have a fixed lid rather than a movable / pivotable lid. In another example, the humidification chamber may not have a lid.

[0034] The tab 20 is configured and arranged to hold a liquid such as water that is used to add moisture to the breathable gas. The tab 20 includes a tab lid portion 22, and the tab lid portion 22 is configured to direct the flow of the breathable gas (air stream) generated by the flow generator 12 along the channel 24 and through the outlet portion 26 of the channel 24 that directs the gas into the tab 20. The tab 20 includes a gas outlet portion 28 for the flow of the humidified breathable gas. The gas outlet portion 28 is connectable to a tube (not shown), and the tube is configured to deliver the humidified gas flow to a patient interface, such as a mask. The tab can have different configurations, for example, having inlet and / or outlet portions in different locations.

[0035] Figures 2A and 2B show an exemplary humidifier tab 20 separated from the humidifier chamber 16. The tab is removable from the humidifier chamber 16 and it is possible to fill the tab with water or to wash the tab. The lid portion 22 of the tab connects to the tab bottom or bottom container 30, and the lid portion 22 and the tab bottom 30 are combined to form the tab 20. When the tab 20 is installed in the humidifier chamber 16, the tab bottom 30 is in thermal contact with the heating device or heating assembly 36 of the humidifier chamber 16 shown in FIG. 3. The tab bottom 30 includes a thermally conductive material such as a metallic material such as aluminum, copper, brass, or stainless steel, or any other alloy, or a suitable thermally conductive material for conducting heat received from the heating device 36 to the liquid contained inside the tab 20. In the example, the tab bottom is formed entirely of metal. Alternatively, the tab bottom can have a bottom plate 32 formed of a thermally conductive material, while the remaining portion of the tab is formed of another material, for example, a plastic material. Alternatively, the tab bottom and the heating device can be integral, for example, the bottom plate and the heating device can be integral. That is, the heating device can form the tab bottom and directly heat the liquid contained inside the tab. In FIG. 3, the heating device is shown as being planar and at the bottom of the chamber 16, but the heating device can have other forms and can be in other positions relative to the chamber and the tab. In another example, the heating device is positioned in other regions such as on the side wall portion of the tab and can be in direct contact with the liquid to be heated. In another example, the heating device is shaped to fit the side wall portion 34 of the humidifier chamber 16 and can be in contact with the metallic portion of the side wall of the tab. In another example, the heating device can be provided in the tab and raised from the tab bottom 30 such that water is provided to cover the upper and bottom surfaces of the heating device. The tab designs, shapes, and configurations described herein are exemplary, and other tabs and liquid containers can be suitable for the technology of the present invention.

[0036] As shown in FIG. 3, the bottom 40 of the cradle is provided under the heating device 36, and the heat insulating layer 38 is provided between the heating device 36 and the bottom 40 of the cradle. The bottom 40 of the cradle can be a bottom plate that is detachable with respect to the humidifier chamber 16. The bottom 40 of the cradle can include a flat surface 41 structured to form a seating portion for the heat insulating layer 38 and the heating device 36. The heat insulating layer 38 can be separable from the bottom of the cradle and the heating device, or can be joined to the bottom of the cradle and / or the heating device. The heat insulating layer is structured to prevent excessive heat transfer to the bottom 40 of the cradle, avoid scalding a person touching the bottom cradle, or damaging furniture on which the humidifier chamber is seated. In an alternative example, since heat transfer from the heating device 36 to the tab bottom 30 may be substantially effective and heat dissipation towards the bottom 40 of the cradle may not be important, the heat insulating layer 38 may not be provided.

[0037] The electrical lead wire 42 is connected to the heating device 36 and supplies power to the electrical components of the heating device 36. The electrical lead wire 42 can extend to an electrical connection inside or outside the humidifier chamber 16. The electrical lead wire can connect the heating device to the control device 43, and the control device 43 can be connectable to a power supply source such as an electrical wall outlet. The control device can adjust the voltage or current applied to the heating device. In an example, the control device can provide one or more of the following: a power switch, temperature detection, fault detection (e.g., disconnection, short circuit, overheating, poor connection, sensor, water ingress to the PCB, CPU, power device, power switch), fault protection, and / or an electrical interface to the heater.

[0038] Heating device Figures 4 and 5 show a heating device or heating assembly 36 according to an example of the technology of the present invention. As shown, the heating device 36 includes a hot plate 44 (also referred to as a heatable element, metal board, or substrate), a thermally conductive laminate layer 46, a heating element 48, a protective layer 50, at least one electrical component 52 (for temperature detection and / or protection), and an electrical lead wire 42 that supplies electricity to the heating element 48 and the at least one electrical component 52.

[0039] As described below, the heating device according to an example of the present technology provides an assembly that is easier to process, more efficient, more reliable, and less costly.

[0040] Hot plate The hot plate 44 includes a thermally conductive material such as aluminum (e.g., anodized aluminum), stainless steel, copper, or any other suitable metal or metal alloy, and forms a metal alloy plate such as an aluminum plate, a stainless steel plate, or a copper plate. The metal hot plate can have a surface treatment such as being anodized to form a corrosion-resistant protective oxide layer. The hot plate can be thin, having a thickness in the range of about 0.6 mm to 1.6 mm, for example, 1.0 mm to 1.5 mm. In an example, the hot plate can constitute a significant proportion of the overall thickness of the heating device. For example, the heating device includes a hot plate, a thermally conductive laminate layer, a heating element, and a protective layer, and the heating device can similarly be thin, having a thickness in the range of about 0.5 mm to 1.7 mm, for example, 1.1 mm to 1.6 mm, and all of the heating device thickness except for about 0.1 mm to 0.2 mm is due to the hot plate. In an alternative example, the hot plate can be formed from other suitable materials such as thermally conductive non-metallic materials such as ceramic materials and thermally conductive plastics.

[0041] Thermally Conductive Laminate Layer The thermally conductive laminate layer 46 can be a coating, layer, or board that is joined to the hot plate. The thermally conductive laminate layer 46 has good thermal conduction properties but includes a material with low electrical conductance (e.g., relatively high electrical resistance), and thus can be referred to as a dielectric laminate layer. The thermally conductive laminate layer can be a composite layer of dielectric particles embedded in a filler material such as resin. For example, the laminate layer 46 can include dielectric materials that are electrically insulating, such as ceramics, polymers, polymers and ceramics, polymers mixed with inorganic particles, such as polytetrafluoroethylene like Teflon (registered trademark), polyimide, boron nitride, alumina, beryllium oxide, aluminum nitride, boron nitride, epoxy composites, and ceramics coated with fiberglass, and can be arranged to form an electrically insulating layer. In the example, the breakdown voltage of the laminate layer can exceed 2 kV. Further, the laminate layer 46 can be rigid or flexible and can have several other shapes that can be planar or conform to the bottom and / or sides of the tab.

[0042] The thermally conductive laminate layer 46 provides electrical insulation between the heating element 48 and the hot plate 44. Also, the thermally conductive laminate layer is also an efficient conductor of the heat generated by the heating element 48 and transfers heat to the hot plate 44. The heat generated by the heating element 48 efficiently flows through the thermally conductive laminate layer and through the hot plate 44 to the tab and to the water contained within the tab. Thus, the heat generated by the heating element 48 is drawn away from or dissipated from the heating element 48 and transmitted towards the hot plate 44. That is, the high thermal conductivity of the laminate layer 46 and the hot plate 44 provides an effective thermal conductivity gradient, which enables the heat to flow efficiently from the heating element 48 through the laminate layer 46, the hot plate 44, and to the tab 20. The hot plate 44 functions as a heat sink, and the heat sink extracts the thermal energy generated within the heating element 48 and distributes the energy to heat the water within the tab. Heat is collected and stored at the hot plate 44 for use when heating the tab bottom 30. The thermally conductive tab bottom 30 is in thermal contact with the hot plate 44, receives the heat, and uses the heat to heat the liquid contained within the tab 20, thereby adding moisture to the pressurized gas (e.g., 4 - 20 cmH2O) passing through the tab.

[0043] In an example, the laminate layer 46 has a dielectric thermal conductivity in the range of 0.5 to 4 watts per meter - kelvin (W / m.k), for example, in the range of about 0.5 to 1.00 or more. The laminate layer can be, for example, a thin layer from 20 micrometers (μm) to 160 μm, for example, 60 - 120 μm. The thinness of the laminate layer contributes to a minimal resistance to heat transfer through the laminate layer.

[0044] In an example, the heating device may not include separate hot plates 44. Rather, the thermally conductive laminate layer 46 itself can form the heating surface. This configuration can provide a flexible circuit arrangement. In the example, the heating element 48 can be disposed between two layers 57, 58 of a thermally conductive laminate material (e.g., a flexible polyimide film such as Kapton (registered trademark)). One or more thermally conductive substrates, pads, pins, or contacts 61, such as metal substrates, pads, contacts, or pins (e.g., made from aluminum, stainless steel, copper, etc.), can be joined to a portion (e.g., an edge portion) of the heating element 48 to form the connection portion 59. The exposed portion of the heating element 48 adjacent to the substrate 61 forms the electrical contact 63 and can receive power. The connection portion 59 can be formed before additionally forming a protective layer (such as those described later) overmolded on top of the heating element 48. The arrangement of the connection portion 59 provides a matrix connector that enables direct electrical and / or thermal contact with the heating element 48 and is capable of performing additional functions (e.g., temperature detection of the heating element).

[0045] Heating element The heating element 48 can be formed from an electric resistance heating material such as copper, electric heating alloys such as iron-nickel alloy, copper-nickel alloy, iron-chromium-aluminum alloy, nickel-chromium alloy, as well as other materials such as PTC ink material, carbon ink material, copper foil, and other materials having a relatively low electric resistance, or combinations thereof. The heating element 48 can include a metal foil, track, or strip arranged in a meandering pattern like a column (e.g., see FIG. 5). It is noted that each line of the heating element 48 in FIG. 5 represents a "track". The heating element 48 can be printed or applied to the thermally conductive laminate layer 46 as shown in FIG. 5. The layout of the heating element and the shape of the meandering pattern can depend on the shape of the bottom plate 32 of the tab. In use, the heating element converts electrical power into thermal energy.

[0046] In an example, the tracks of the heating element 48 can be evenly distributed across the laminate layer to provide a uniform heating profile to the hot plate 44. For a target heating performance, the track design of the heating element depends on a number of factors. For example, the resistivity of the heating element material affects the track layout design and the track coverage of the laminate layer 46 and the hot plate 44. In another example, the heating alloy is a better electrical resistance heater material compared to copper. Thus, to achieve a similar heating profile, a copper heating track can be narrower (e.g., in the range of about 0.3 mm to 2 mm, e.g., 0.4 mm to 1 mm) and longer compared to a heating track made of a heating alloy or aluminum. In such a configuration, a larger area of the heating device can be covered to achieve a similar desired heating profile. Those skilled in the art will understand that other track configurations can be provided to generate different heating profiles.

[0047] FIG. 7 shows a heating element 248 including an alternative example of a track layout or pattern. As shown, the tracks or strips are arranged in a manner such as concentric rings. Advantages of this layout include improved thermal distribution and improved tolerance for thermal expansion / contraction of the tracks when the tracks are heated / cooled. Also, this layout improves the resistance accuracy during the heating process.

[0048] Protective layer The protective layer 50 can include materials commonly used as a "solder mask", such as, for example, polymers or acrylics. The solder mask is conventionally printed or otherwise applied to coat the printed circuit board (PCB), the thermally conductive laminate layer, and the conductive traces of the heating element during the manufacturing process of the PCB and the metal core printed circuit board (MCPCB). In the context of a heating device, the protective layer can be printed or otherwise applied to coat the heating element 48 and the thermally conductive laminate layer 46. The heating element is sandwiched between the protective layer 50 and the thermally conductive laminate layer 46. The protective layer 50 can extend beyond the peripheral edge of the heating element 48 and directly coat a portion of the thermally conductive laminate layer 46 (see, for example, the right edge of the device shown in FIG. 4-1).

[0049] Exemplary materials for the protective layer 50 include, for example, screen-printable epoxy masks, liquid photosensitive solder masks (IPSM), and dry film photosensitive solder masks (DFSM). The protective layer 50 seals the heating device 36, prevents leakage current, and protects the laminate layer 46 and the heating element 48 against environmental factors such as corrosion and physical scratching. The protective layer 50 can be printed on the surface of the hot plate 44 not covered by the laminate layer or otherwise applied so as to directly coat it. Also, the protective layer 50 can provide electrical insulation and some thermal insulation between the heating element 48 and the insulating layer 38 at the cradle bottom 40 of the humidifier chamber 16.

[0050] The protective layer 50, such as a solder mask, can be applied to cover the laminate layer 46 and the heating element 48 by screen printing, by well-known mask printing techniques, or as a sheet bonded with an adhesive to the heating element and the laminate layer. Further, a stencil can be positioned over specific locations on the heating element and the laminate layer such that contact pads, and possibly other locations, are not coated by the protective layer. After the protective layer has been printed, applied, or otherwise bonded to the heating element and the laminate layer, the stencil can be removed to expose the contact pads and other locations that are to be exposed.

[0051] The contact pads, and / or other conductive portions of the heating element, can be exposed through the protective layer 50, for example, to enable connection of electrical lead wires to the heating element by surface mount technology. These openings in the protective layer for the contact pads can be automatically applied during an automated printing or coating process.

[0052] Electrical lead wires The electrical lead wire 42 provides a conductive path for the power from the power supply source that will be applied to the heating element 48. The electrical lead wire can be connected to a wire that is compatible with the power supply source, such as a transformer or an inverter, or to a wire that is compatible with a wall power outlet through appropriate insulation. When power is applied through the electrical lead wire 42, heat is generated by the electrical resistance heating of the heating element 48. The heat generated by the heating element 48 is transmitted through the thermally conductive laminate layer 46 and the hot plate 44 to the bottom plate 32 of the humidifier tab 20 to heat the water in the humidifier tab 20.

[0053] Contact pad The heating element can include conductive or contact pads 53, 54, which are printed or placed on the laminate layer 46. The conductive pads provide electrical connection points for the electrical lead wires 42, such as the conductive pad 53 that provides the positive power terminal and the conductive pad 54 that provides the negative power terminal. Power flows from the power source through the lead wires, the power terminals, and the heating element 48. Additional contact pads can be used to provide electrical connection to one or more other electrical devices or contacts (such as one or more spring contacts) on the laminate layer 46. For example, as shown in FIG. 5, the electrical component 52 described with respect to FIG. 4-1 can include a thermosensor 52A and a thermal fuse 52B, and the thermosensor 52A and the thermal fuse 52B are connected to the tracks of the heating element 48. The electrical connection provided by the contact pad 56 (such as the thermosensor positive terminal) can be between the thermosensor 52A and another power source provided by a different set of lead wires for separately providing power to the thermosensor 52A. If the required power for one or more other electrical devices (such as the thermosensor 52A) is different from the required power for the heating element, a separate power source can be provided. The thermal fuse 52B can be mounted on top of the solder mask and can be connected to a contact pad that makes electrical contact with the heating element. When the heat becomes excessive, the thermal fuse stops the current flow through the heating element. The electrical connection between the contact pad and the electrical lead wire or sensor wire can be made by soldering or by any other known electrical connection process, such as automated surface mount technology.

[0054] In an example, a power supply with a nominal voltage between 12 volts (V) and 36V (such as between 8V and 40V) provides power to the heating element 48. Other voltages can be used according to the appropriate operating parameters of the heating element 48. The heating element 48 can substantially cover the entire range of the laminate layer while allowing for a margin for clamping during the coating process (e.g., applying a solder mask) to enable the application of the printed protection layer 50.

[0055] Assembly The heating device 36 can be formed using known printed circuit board (PCB) manufacturing techniques for making metal PCBs, such as metal core printed circuit board (MCPCB) technology. These techniques are highly automated and adapted to apply conductive tracks on the metal PCB. In an MCPCB, the metal plate serves both as a printed circuit board base part and as a heat sink for electronic components mounted on the plate. Heat from the electronic components is dissipated by the metal plate, avoiding overheating of the electronic components. The metal plate can be formed from any suitable thermally conductive metal (e.g., aluminum, stainless steel, or other thermally conductive metals, or a thermally conductive polymer or plastic).

[0056] For example, the heating element 48 can be applied to the thermally conductive laminate layer 46 using MCPCB manufacturing techniques for making metal PCBs. The heating element can be applied by printing conductive tracks on top of the laminate layer 46. Also, by applying a conductive sheet to the laminate layer, applying a mask to the sheet shaped as a mirror image of the desired pattern of the heating element, and etching away the portions of the conductive sheet not covered by the mask, the heating element can be formed. Further, the heating element 48 can be formed on top of the laminate layer 46 by means of vacuum deposition techniques. Additionally, the serpentine pattern of the heating element can be selected based on the shape of the bottom of the water tab and the amount of thermal energy to be delivered to the tab.

[0057] In another example, a PCB including a metal layer, a dielectric layer, and a copper layer can be selected based on size / performance characteristic requirements. Copper heating tracks are created, for example, by etching, within the copper layer, according to the track specifications. A printed protection layer (e.g., solder mask) is applied to cover the heating tracks. The track / printed protection layer can be adapted to provide electrical connection points for surface mounting (or soldering) electrical components (e.g., thermo-fuses, thermo-sensors).

[0058] The assembly process disclosed herein for the heating device is fully or almost fully automated, which enables the production of heating devices with high quality and uniform consistency. Also, the assembly process disclosed herein can result in a reduction in the assembly cost for the heating element and a reduction in the repair or replacement cost due to automation. In addition, such PCB technology uses advanced heat transfer structures, materials, and techniques, provides a very simple structure, offers excellent thermal performance, has very few safety concerns, provides easy quality control and high yields, and / or provides an easy increase in mass production capacity and large quantity supply.

[0059] FIG. 5 shows an example of a heating device 36 formed by a metal printed circuit board printing and manufacturing process. FIG. 5 shows heating elements 48 arranged in rows on a thermally conductive laminate layer 46. The laminate layer 46 can coincide with or have the same extent as the hot plate 44 (e.g., as shown in FIG. 5, showing the hot plate 44 below the laminate layer 46), or the periphery of the hot plate 44 can extend slightly beyond the periphery of the laminate layer 46 (e.g., as shown in FIG. 4-1).

[0060] In FIGS. 3 to 5 described above, the heating device is provided as a separate structure distinct from the humidifier tab, which is adapted to contact the tab and heat the liquid contained inside the tab. Alternatively, the heating device can be integral with the tab, form the bottom of the tab, and be adapted to directly heat the liquid contained inside the tab. Examples of such direct heating devices are described below.

[0061] FIG. 6 shows a humidifier tab or water tab 60 for heating water 62, in accordance with an example of the present invention technology. The tab can be suitable for seating within a humidifier chamber or can be provided as a stand-alone device. The tab 60 includes a side wall portion 64, or side wall portion segment, or tab side wall, that extends around the entire perimeter of the tab, and a bottom wall portion 66 that joins to the side wall portion. A heating device or heating assembly 68 is incorporated within the bottom wall portion 66. In the example, the side wall portion 64 and the bottom wall portion 66 (e.g., formed from plastic) are overmolded onto the heating device 68. In the example shown, the bottom wall portion 66 is formed to cover the peripheral edges of a dielectric layer 72, a heating element 74, and a protective layer 76. In an alternative example, as described above, the protective layer can cover one or more layers of the heating device.

[0062] The heating device 68 is formed as a laminate of a hot plate 70, a thermally conductive dielectric layer 72, a heating element 74, and a protective layer 76. The hot plate can be a metal plate having a first side with an anodized coating, which is adapted to form the inner surface of the bottom of the tab that is exposed to water 62. The opposite side of the hot plate receives the thermally conductive dielectric layer 72, which can be a resin comprising dielectric particles, as described above.

[0063] The heating element 74 can be a meandering track of metallic foil, for example, forming a meandering track of conductive foil, which is printed on the side of the dielectric layer 72 on the opposite side of the hot plate 70 or applied in some other way. The contact pads 78 can be disposed at each end of the track of the heating element or near the edge of the hot plate, enabling spring-type electrical contacts. The contact pads 78 can be exposed through the protective layer 76. Further, the contact pads can be formed by raised terminals that protrude slightly from the bottom wall portion 66 of the tab. Such an arrangement enables the contact pads 78 to engage with the power terminals, for example, at the bottom of a humidifier chamber that supplies power to the heating element. For example, FIG. 13 illustrates a direct-heating humidifier tab including a heating device 668, where the heating device 668 forms the bottom wall portion of the tab (e.g., the heating device is provided at the bottom of the tab by overmolding or clip-in). FIG. 13 shows the hot plate 670, the heating element 674, and the protective layer 676 of the heating device, with the contact pads 678 exposed through the protective layer 676. In use, when the tab is engaged with the humidifier chamber (e.g., a push-down type electrical contact connection configuration), the exposed contact pads 678 can engage with the power terminals or spring-type electrical contacts 682 at the bottom of the humidifier chamber.

[0064] The edge 80 at the peripheral portion of the hot plate 70 can fit (e.g., snap fit) into a groove at the lower edge of the side wall portion 64. The edge 80 can extend beyond the edges of the protective layer 76, the heating element 74, and the dielectric layer 72. The joint between the edge 80 of the hot plate 70 and the side wall portion 64 can be sealed to fix the heating assembly to the side wall portion and prevent leakage of water from the tab. In the example, as described above, the side wall portion 64 can be overmolded onto the edge 80 of the hot plate 70.

[0065] As shown in FIGS. 11 and 12, the heating assembly can include protective coatings 469, 569 provided to cover the hot plate. The protective coating can be overmolded to cover the hot plate and provide a water- and / or steam-sealed protective layer across the entire heating surface. The protective coating is thermally conductive and is adapted to effectively transfer heat from the hot plate to the water in the tab. Moreover, the protective coating is preferably formed from a biocompatible material and can be formed from other thermally conductive plastic materials such as silicone, Teflon®, UV curable polymers, or products such as CoolPoly™. Also, the protective coating can provide a surface that is easily washable.

[0066] Moreover, the protective coating can enable the heater assembly to be inserted into or positioned directly within the water tab body portion, which can provide improved thermal performance. The use of the overmolded protective coating is further described in U.S. Application No. 61 / 611,137, filed Mar. 15, 2012, which is hereby incorporated by reference in its entirety.

[0067] FIG. 11 shows an example of a humidifier tab having an open base portion or bottom. As shown, tab 460 includes a plastic-molded side wall portion 464 and a heating device 468, which cooperate to define a water chamber or compartment for water 462. The heating device includes an overmolded protective coating 469, a thermally conductive hot plate 470 (e.g., a metal hot plate), and a heating element 474 having a heating track in contact with the hot plate 470. As shown, the heating device is disposed at an upward spacing from the lower end of the side wall portion 464. The side wall portion can be overmolded over the heating device without a bottom wall portion or bottom protective layer. Other materials with high heat insulation can be used for overmolding. Also, an insulator or a bottom wall portion (not shown) can be provided on the tab below the heating element 474.

[0068] FIG. 12-1 shows an example of a humidifier tab having a closed base portion or bottom. As shown, tab 560 includes a plastic-molded side wall portion 564, a plastic-molded bottom wall portion 566, and a heating device 568, which cooperate to define a water chamber or compartment for water 562. The heating device includes an overmolded protective coating 569, a thermally conductive hot plate 570 (e.g., a metal hot plate), and a heating element 574 that provides a heating track. The side wall portion and the bottom wall portion can be overmolded over the heating device.

[0069] In another example shown in FIG. 12-2, the inner portion of the tab 560 can be overmolded with a thermally conductive plastic, and the hot plate 570 and the heating element 574 are embedded in the overmold to form a heating device 868. The overmold 861 includes a bottom wall portion 867 overmolded on the bottom wall portion 566 of the tab and an intermediate wall portion 872 covering the hot plate 570. Also, the overmold 861 can include a side wall portion 863 overmolded on the tab side wall portion 564. This arrangement can form a biocompatible, washable, water / vapor sealed protective layer.

[0070] In an alternative arrangement of the heater assembly, the overall assembly can be formed in a different configuration such that a thermally conductive hot plate is no longer required, as shown in FIGS. 15-1 and 15-2. Referring to FIG. 15-1, a support substrate 990 is provided on the lower surface of the tab, and on it, a heating element 974 is joined or applied in the same manner as described above with respect to applying the heating element 48 to the hot plate 44. In another example, the heater assembly can be directly assembled into the surface of the water tab, such as the bottom surface.

[0071] The thermally conductive protective coating 969 is overmolded to cover the heating element 974 as described above, providing electrical insulation, corrosion resistance, and / or damage protection. In this arrangement, the heating element 974 is positioned towards the water to be heated, and the support substrate 990 is positioned relatively away from the water. The support substrate 990 mainly serves as a base for receiving a printed circuit and does not function as a heat sink or a conductive means for heating water. In this arrangement, the heater assembly is inverted compared to the embodiment described above using a metal hot plate, and heat transfer occurs in the opposite direction. The heating element 974 is essentially exposed to the water and, as a result, can provide improved thermal conductivity and thermal efficiency. Also, such an arrangement can provide more accurate or direct water temperature detection.

[0072] The support substrate 990 can be formed from a lower-cost PCB type material such as a composite epoxy material (CEM) of different grades (e.g., CEM3), from a glass fiber-reinforced epoxy laminate such as FR-4, or from other such PCB type materials. Also, the support substrate 990 can be configured to provide a heat insulating material on the outer surface of the tab.

[0073] In such an arrangement, electrical connections are positioned on the inner surface of the tab. Electrical connections for temperature detection, or safety switches, can be directly connected to the heating element 974 before overmolding the heating element 974 in the tab.

[0074] As shown in FIG. 15-2, the protective coating or layer 1073 can include a thin layer of stainless steel applied to cover the heating element 1074. The stainless steel layer can be applied in any suitable manner that provides thermal contact between the stainless steel and the heating element. The thin layer of stainless steel can have a thickness less than 1.2 mm (e.g., from 0.05 to 1 mm). A thermally conductive laminate layer 1075 (e.g., Kapton™ film) can be provided between the protective coating 1073 and the heating element 1074 to provide electrical insulation. Also, the thermally conductive laminate layer 1075 can include a thermal adhesive (e.g., a double-sided adhesive) and can be used to attach the protective layer 1073.

[0075] The stainless steel layer can provide one or more of the following benefits: a protective cover for the heating element, corrosion protection, and high rigidity for the heater assembly (e.g., the stainless steel layer can cause the heater assembly to be formed into a high-rigidity structure).

[0076] In another example, the heating element 1074 can be formed without a thick support substrate 1090, and the thin stainless steel layer serves to provide support for the flexible heater element while also providing a more flexible heater assembly that can be configured to conform to the shape of a water tab.

[0077] Electrical contacts As described above, the heating device 68 can have exposed contacts (i.e., exposed contact pads 78) and is adapted to engage mating contacts that supply power when tabs are installed on the bottom of the humidifier chamber. In such an example, the contacts in the humidifier chamber can be spring-loaded and such contacts must be pressed to effect an electrical connection. For example, the contacts in the humidifier chamber engage only when the lid of the humidifier is closed to hold the humidifier tabs in the humidifier chamber.

[0078] Figures 8 through 10 illustrate another example of an electrical connection for a heating device. In this example, the heating device 368 integrated into the bottom of the humidifier tab 360 includes an exposed portion 371 that is adapted to engage an electrical contact structure 380 provided in the humidifier chamber when the tab is slid to an operating position in the humidifier chamber, i.e., for a slide-in type of electrical connection.

[0079] As shown, the electrical contact structure 380 is in the form of a socket and includes a metal spring arm 382 therein. In use, the exposed portion 371 of the heater device engages the metal spring arm 382 in the electrical contact structure 380 to effect an electrical connection. The advantage of this connection is the presence of a "self-cleaning" aspect where each slide-in / slide-out rubs one surface against another, wiping away any oxide deposits so that deposits of metal oxide on the connection points are removed.

[0080] Figures 14A and 14B show another example of a slide-in type electrical connection for a heating device. In this example, a metal spring arm 782 is pivotally mounted within an electrical contact structure 780. In use, the end portion of the heating device 786 can slide into the contact structure 780 and abut against a stub 785, and the stub 785 pivots to lift the spring arm 782 into an electrical contact including a contact pad 778 that is exposed at the bottom of the heating device, for example, a pivot type slide-in connection. Such a pivoting connection ensures that only the spring arm 782 contacts the exposed contact pad during use, that is, the spring arm avoids contact and potential wear of the protective surface at the bottom of the heating device.

[0081] As shown in FIG. 9-1, by overmolding an additional outer protective coating 1192 around at least a portion of the heater assembly, a protective contact edge 1183 can be formed in the connector region. Referring to FIG. 9-1, the heater assembly includes a support substrate 1190, a heating element 1174 (e.g., a copper layer), an overmolded protective coating 1193 on top of the heating element 1174, and an outer protective coating 1192. The outer protective coating 1192 is overmolded on the bottom surface of the support substrate 1190 and around the outer edge of the heater assembly, providing a protective coating along the edge of the connector region of the heater assembly. The heating element is exposed from the outer protective coating 1192 in the connector region and can provide a contact portion for the electrical contact arm 1182. The contact portion is provided with a nickel layer (e.g., 20 μm to 80 μm) and a gold layer covering the nickel (e.g., 20 μm to 50 μm), and this range can be protected. The outer protective coating 1192 can provide a rigid or semi-rigid support to the heater assembly. Also, the outer protective coating 1192 can protect the electrical connection from water discharge.

[0082] Temperature detection Temperature detection of the heating device can be provided for fault reduction and temperature feedback control. For example, it is possible to determine the temperature of the heating device or water, and then, if the temperature is too high, the power to the heating element can be stopped. Regarding temperature feedback, the temperature of the heating device or water can be determined to better control the power supply profile and reconcile the required level of evaporation / humidification.

[0083] The temperature of the heating device or water can be determined in an alternative manner. Alternative examples of sensors for determining the temperature of the heating device are described below.

[0084] Non-contact sensor A non-contact type of sensor can be provided to determine the temperature of the heating device. Such a non-contact type of sensor is arranged at a distance from the heating surface or heating track of the heating device.

[0085] In an example, an infrared (IR) sensor is positioned near the heating surface of the heating device, senses the radiation (heat) generated from the heating device, and can determine the temperature of the heating device. An example of such an arrangement is shown in Figure 8-1A, which shows an IR sensor 383 near the heating surface of the exposed portion 371 of the heating device.

[0086] In another example, a convection sensor is positioned near the heating surface of the heating device (e.g., positioned in the same way as the sensor shown in Figure 8-1A), senses the temperature of the air in the gap between the convection sensor and the heating device, and can determine the temperature of the heating device.

[0087] Contact sensor A contact type of sensor can be provided to determine the temperature of the heating device. Such a contact type of sensor is in contact with the heating surface or heating track of the heating device.

[0088] In an example, the sensor can include a thermoresistive material whose material resistance changes as the temperature changes. By measuring the resistance change, the temperature can be determined.

[0089] In another example, the sensor can include a thermomagnetic switch, in which the magnetic field strength changes as the temperature changes. By measuring the change in magnetic field strength, the temperature can be determined.

[0090] In another example, the sensor can include a bimetal strip material, in which the shape or elasticity of the metal changes with temperature. By measuring the change in shape or elasticity, the temperature can be determined. An exemplary advantage of this example is that the strip material can disconnect the connection at a specific temperature and thus provide a thermal fuse for the system. Also, such an off-heater sensor configuration can be a resettable switch that combines the sensor and manual operation.

[0091] On-board temperature detection and thermal fuse In an example, as shown in FIG. 5 and as described above, a thermosensor 52A can be provided on the heating element to measure the temperature of the heating track, and a thermal fuse 52B can be provided to stop the current flow through the heating element when the heat becomes excessive. Also, the heating track itself can be a temperature sensor.

[0092] Temperature detection capability In the technology of the present invention, the heating device can be formed using known PCB manufacturing techniques for creating metal PCBs, such as MCPCB technology. Such a heating device according to the technology of the present invention provides a heating profile that is substantially uniformly distributed across the heater device. For example, the temperature difference (ΔT) across the hot plate during temperature rise is very small, (showing very high thermal conductivity and rapid heat transfer,), low thermal stress of the hot plate and the surrounded material during temperature rise and operation, low thermal / mechanical stress of the hot plate and the surrounded material during temperature rise and operation, and a low back surface temperature that does not cause the bottom of the casing to heat up.

[0093] The temperature transfer from the heating track to the metal hot plate is efficient, and thus the temperature of the surface of the hot plate is likely to be the same as the temperature of the surface of the heating track (low temperature gradient / heat sink). Since the track resistance varies with the track temperature, the current (I) and voltage (V) circuit measurements can calculate the resistance (R) of the track (R = V / I) and can be used to know the R vs T profile, and it is possible to determine the temperature of the hot plate simply by determining R. In this way, separate NTC (negative temperature coefficient) thermistor components may not be necessary to sense the temperature. Also, such a conversion circuit can be used for fault detection and protection, such as heater overheating, open circuit, or poor connection or short circuit.

[0094] Temperature Limitation / Overheat Protection In an example, the heating device according to the technology of the present invention can provide a heating surface temperature that can only reach a predetermined maximum temperature for a selected predetermined input power. This is due to the efficient heat transfer from the heating track to the heating surface, the effective heat dissipation from the heating surface, and the copper heating track that reaches the limiting temperature due to a given power input. Given this, since the heating device has overheat self - protection ability, the thermo - fuse (for mitigating against overheating) can optionally be removed. The removal of the thermo - fuse can result in savings in component and assembly costs.

[0095] In a further example shown in FIG. 9 - 2, the heating track can be formed from a polymer thick film (PTF) 1274 in combination with a copper conductor (e.g., the heating track) 1295, and the copper conductor 1295 is printed on a hot plate (e.g., the hot plate 44 described in the above example) or the support substrate 1190. The copper conductor 1295 and the PTF 1274 are provided in appropriate amounts to provide a variation in heating across the heating element. The PTF 1274 includes a positive temperature coefficient (PTC) and can provide detection and thermal protection functions. The copper conductor 1295 forms a contact portion and serves as a conductor for electricity from the electrical contact arm 1182, and the PTF 1274 serves as a heater. A nickel layer (e.g., 20 μm to 80 μm) and a gold layer covering the nickel (e.g., 20 μm to 50 μm) can be provided at the contact portion to protect this area. Also, the heater can be formed by the copper track 1295 in combination with the PTF 1274 to achieve the required heating and protection characteristics. In the example, one or more sections of the PTF 1274 can be continuously provided with the copper track 1295 to form a temperature fuse.

[0096] In an exemplary manufacturing step, the heating device can be surrounded or otherwise covered with stainless steel, which provides the advantage of protecting the heating device from corrosion. This process can be used as an alternative or in combination with the step of anodizing a hot plate. The result of this manufacturing step is a heating device surrounded or otherwise covered with stainless steel. As an alternative to stainless steel, another thermally conductive material that is scratch resistant and corrosion resistant, such as anodized, die cast, hard aluminum, can be used to surround or cover it.

[0097] The present invention technology is particularly useful in lower temperature heating applications (e.g., below 100°C, or below 80°C, or below 70°C). Moreover, the power output can be less than about 5 W / cm2, or less than about 2 W / cm2, or less than about 1 W / cm2, for example, approximately 0.6 W / cm2. Higher temperature applications may require a power output of approximately 60 W / cm2. Moreover, the present invention technology facilitates the use of lower cost materials and lower cost processes than those required for higher temperature applications. For example, in the present invention technology, an etching manufacturing process can be used instead of printing a thermally conductive ink. The etching process can produce a more accurate heating track than the printing process. Moreover, high temperature processes and applications require inorganic dielectrics and associated higher material and process costs, but the present invention technology enables the use of less expensive dielectric materials such as organic materials. Moreover, the present invention technology enables the use of a lower cost hot plate, for example, a hot plate made of aluminum or another lower cost material.

[0098] Although the present technology has been described in connection with several examples, it should be understood that the present technology should not be limited to the disclosed examples, but rather is intended to cover various modifications and equivalent configurations included within the spirit and scope of the present technology. Also, the various examples described above can be implemented in combination with other examples. For example, one or more aspects of one example can be combined with one or more aspects of another example to realize still other examples. Furthermore, each independent feature or component of any given assembly can constitute additional examples. In addition, although the present technology has a specific application to patients suffering from OSA, it should be recognized that patients suffering from other diseases (such as congestive heart failure, diabetes, morbid obesity, stroke, bariatric surgery, etc.) can benefit from the above teachings. Moreover, the above teachings are equally applicable to non-medical uses, to patients, and to those who are not patients.

[0099] [Appended Claim 1] A tab adapted to hold a liquid, and A heating device comprising a substrate having an etched heating track A humidifier comprising the same. [Appended Claim 2] The humidifier according to appended claim 1, wherein the substrate includes a thermally conductive substrate layer, a layer of copper or alloy or positive temperature coefficient (PTC), and a dielectric laminate layer between the thermally conductive substrate layer and the layer of copper or alloy or PTC. [Appended Claim 3] The humidifier according to appended claim 2, wherein the thermally conductive substrate layer is made of metal. [Appended Claim 4] The humidifier according to any one of appended claims 2 to 3, wherein the dielectric laminate layer is made of a ceramic material, a polymer material, or a mixture of ceramic and polymer materials. [Appended Claim 5] The humidifier according to any one of appended claims 2 to 4, wherein the heating track is etched in the layer of copper or alloy or PTC. [Additional Item 6] The humidifier according to claim 5, wherein the heating track is associated with an electrical lead wire and a contact pad for at least one electrical component. [Additional Item 7] The humidifier according to any one of claims 5 to 6, wherein the heating track includes a width in the range of about 0.4 mm to 2 mm. [Additional Item 8] The humidifier according to any one of claims 5 to 7, wherein the temperature of the heating device is determined by determining the resistance of the heating track. [Additional Item 9] The humidifier according to any one of claims 2 to 8, further comprising a protective layer printed on at least the layer of copper or alloy or PTC. [Additional Item 10] The humidifier according to any one of claims 1 to 9, wherein the heating device provides a heating surface temperature that can only reach a maximum temperature for a selected input power. [Additional Item 11] The humidifier according to any one of claims 1 to 10, wherein the heating device is provided in a humidifier chamber adapted to receive the tab. [Additional Item 12] The humidifier according to any one of claims 1 to 10, wherein the heating device is integral with the tab. [Additional Item 13] A tab adapted to hold a liquid, A heating device including a metal hot plate, a heating element having a copper or alloy or PTC heating track for providing heat to heat the liquid, a thermally conductive laminate layer composed of a ceramic material or a polymer material between the hot plate and the heating element, and a printed protection layer for covering at least the heating track and a humidifier comprising the same. [Additional Item 14] A tab adapted to hold a liquid, A heating device including a hot plate, a heating element, a laminate layer having thermal conductivity between the hot plate and the heating element, and a protective layer for covering at least the heating element A humidifier comprising The humidifier, wherein the heating element includes a layer of copper or alloy or PTC having a heating track for providing heat to heat the liquid [Additional item 15] The humidifier according to additional item 14, wherein the heating track is etched in the layer of copper or alloy or PTC of the heating device [Additional item 16] The humidifier according to any one of additional items 14 to 15, wherein the heating track is associated with an electrical lead wire or a spring contact and a contact pad for at least one electrical component [Additional item 17] The humidifier according to any one of additional items 14 to 16, wherein the heating track includes a width in the range of about 0.3 mm to 2 mm [Additional item 18] The humidifier according to any one of additional items 14 to 17, wherein the temperature of the heating device is determined by determining the resistance of the heating track [Additional item 19] The humidifier according to any one of additional items 14 to 18, wherein the hot plate is formed of a metal or metal alloy including at least one of aluminum, stainless steel, and copper [Additional item 20] A tab adapted to hold a liquid, A heating device including a hot plate, a heating element, a laminate layer having thermal conductivity between the hot plate and the heating element, and a protective layer for covering at least the heating element A humidifier comprising The humidifier, wherein the protective layer is printed at least on the heating element [Additional item 21] The humidifier according to appended claim 20, wherein the laminate layer is a dielectric laminate layer composed of a ceramic material, a polymer material, or a mixture material of polymers. [Appended claim 22] The humidifier according to any one of appended claims 20 to 21, wherein the protective layer is printed on the laminate layer. [Appended claim 23] The humidifier according to appended claim 22, wherein the protective layer covers the peripheral edge of the heating element and extends over a part of the laminate layer. [Appended claim 24] The humidifier according to any one of appended claims 20 to 23, wherein the protective layer includes a solder mask. [Appended claim 25] The humidifier according to any one of appended claims 20 to 24, wherein the thermally conductive laminate layer has a thickness in the range of about 20 μm to 160 μm. [Appended claim 26] The humidifier according to any one of appended claims 20 to 25, wherein the hot plate is formed of a metal or metal alloy including aluminum, stainless steel, or copper. [Appended claim 27] The humidifier according to any one of appended claims 20 to 26, wherein the contact pad and / or other conductive parts of the heating element are exposed through the protective layer. [Appended claim 28] A process for fabricating a heating device for a humidifier including a tab for holding a liquid, comprising: providing a substrate having a first side and a second side adapted to be in thermal contact with the liquid; etching a heating track on the second side of the substrate; applying a protective layer to the second side of the substrate to at least cover the heating track. A process comprising the above steps. [Appended claim 29] The process according to claim 28, wherein the step of providing the substrate comprises providing a substrate comprising a metallic layer providing the first side, a layer of copper, alloy, or PTC providing the second side, and a dielectric layer between the metallic layer and the layer of copper, alloy, or PTC. [Claim 30] The process according to any one of claims 28 to 29, wherein the step of applying the protective layer comprises printing the protective layer on the second side of the substrate. [Claim 31] The process according to any one of claims 28 to 30, wherein the step of applying the protective layer comprises exposing contact pads and / or other conductive parts associated with the heating track through the protective layer. [Claim 32] A heating element for converting electrical energy into thermal energy, A heatable element having a first surface and a second surface, A dielectric laminate layer between the heating element and the first surface of the heatable element A heating device comprising: The dielectric laminate layer is thermally conductive for transferring thermal energy from the heating element to the heatable element, and the second surface of the heatable element is configured to heat a liquid in a container. [Claim 33] The heating device according to claim 32, further comprising a protective layer covering an outer surface of the heating element and an outer surface of the dielectric laminate layer. [Claim 34] The protective layer extends over and covers a peripheral edge of the heating element and the dielectric laminate layer, and extends over a peripheral portion of the first surface of the heatable element that extends beyond the heating element and the dielectric laminate layer. [Claim 35] The heating device according to any one of appended claims 32 to 34, wherein the dielectric laminate layer is a thin layer including at least one of polytetrafluoroethylene such as Teflon (registered trademark), polyimide, boron nitride, alumina, beryllium oxide, aluminum nitride, boron nitride, epoxy composite material, and reinforced glass fiber. [Appended claim 36] The heating device according to any one of appended claims 32 to 35, wherein the thickness of the dielectric laminate layer is in the range of 20 μm to 160 μm. [Appended claim 37] The heating device according to any one of appended claims 32 to 36, wherein the breakdown voltage of the dielectric laminate layer exceeds 2 kV. [Appended claim 38] The heating device according to any one of appended claims 32 to 37, wherein the heatable element includes a plate made of conductive metal, and the first and second surfaces are opposite surfaces of the plate. [Appended claim 39] The heating device according to any one of appended claims 32 to 38, wherein the heating element includes a foil made of conductive metal arranged in a meandering pattern on the dielectric laminate layer. [Appended claim 40] The heating device according to any one of appended claims 32 to 39, wherein the heating element is a printed circuit board (PCB) made of metal, and the heating element includes tracks of a foil made of conductive metal arranged on the PCB. [Appended claim 41] The heating device according to any one of appended claims 32 to 40, wherein the thickness of the device is not greater than 1.5 mm. [Appended claim 42] The heating device according to any one of appended claims 32 to 41, wherein the second surface is flat. [Appended claim 43] Heating element tracks, Thermally conductive dielectric layer, A thermally conductive board having a first surface adapted to transfer heat into a container and a second surface opposite the first surface, wherein a thermally conductive dielectric layer is sandwiched between the board and a heating element track on the second surface, the thermally conductive board and A printed circuit board heater including Electrical current terminals to the heating track provide application of electrical energy to the heating element track that causes resistive heating of the heating track, and thermal energy from the heating element track is transferred to the board through the thermally conductive dielectric layer, and the board transfers the thermal energy to the container, the printed circuit board heater. [Article 44] The printed circuit board heater according to Article 43, wherein the printed circuit board heater is integral with the surface of the container. [Article 45] The printed circuit board heater according to Article 44, wherein the first surface is shaped to receive the bottom surface of the container. [Article 46] The printed circuit board heater according to any one of Articles 43 to 45, further including a protective layer covering the heating element track layer and the dielectric layer. [Article 47] The printed circuit board heater according to Article 46, wherein the protective layer extends to cover the peripheral edges of the heating element track and the dielectric layer and extends over the peripheral portion of the first surface of the board extending beyond the heating element track and the dielectric layer. [Article 48] The printed circuit board heater according to any one of Articles 43 to 47, wherein the thermally conductive dielectric layer is a thin layer including at least one of polytetrafluoroethylene such as Teflon (registered trademark), polyimide, boron nitride, alumina, beryllium oxide, aluminum nitride, boron nitride, epoxy composite, and reinforced glass fiber. [Article 49] The printed circuit board heater according to any one of appended claims 43 to 48, wherein the thickness of the thermally conductive dielectric layer is in the range of 20 μm to 160 μm. [Appended claim 50] The printed circuit board heater according to any one of appended claims 43 to 49, wherein the breakdown voltage of the thermally conductive dielectric layer exceeds 2 kV. [Appended claim 51] The printed circuit board heater according to any one of appended claims 43 to 50, wherein the thermally conductive board is formed from a metal or metal alloy plate including an aluminum, stainless steel, or copper plate. [Appended claim 52] The printed circuit board heater according to any one of appended claims 43 to 51, wherein the heating element track layer includes a conductive metal foil disposed in a meandering pattern on the dielectric layer. [Appended claim 53] A humidifier including a container for holding a predetermined amount of liquid and a heating device according to any one of appended claims 32 to 52, wherein the heating device is in thermal contact with the liquid to deliver heat to the liquid and generate an air flow from the evaporation of the liquid. [Appended claim 54] Providing a substrate having a first surface adapted to heat the liquid in the container; Applying a thermally conductive dielectric layer to a second surface of the substrate, the second surface being on the opposite side of the first surface; Applying the heating element layer to the thermally conductive dielectric layer such that the thermally conductive dielectric layer is sandwiched between the second surface of the substrate and the heating element layer A method of forming a heating device comprising: [Appended claim 55] The method according to appended claim 54, further comprising applying a protective layer to the heating element layer and the thermally conductive dielectric layer. [Appended claim 56] The method according to appended claim 54 or 55, wherein the substrate is a metal plate and the method is implemented using processing of a metal core printed circuit board. [Appended Item 57] The method according to any one of appended items 54 to 56, wherein the heating element layer is applied as a meandering track of conductive foil on the thermally conductive dielectric layer. [Appended Item 58] The method according to any one of appended items 54 to 57, wherein the thermally conductive dielectric layer is applied as a composite layer of dielectric particles and resin. [Appended Item 59] The method according to any one of appended items 54 to 58, further comprising the step of integrating the formed heating plate with the bottom of the liquid container. [Appended Item 60] The method according to any one of appended items 54 to 59, further comprising the step of printing the heating element layer as a meandering pattern on the thermally conductive dielectric layer. [Appended Item 61] A tab adapted to hold liquid, A heating device including a heating element having a first side and a second side, the heating element including a heating track, A first thermally conductive laminate layer provided on the first side of the heating element, A second thermally conductive laminate layer provided on the second side of the heating element and a humidifier. [Appended Item 62] The humidifier according to appended item 61, wherein a substrate is provided at an end portion of the heating element and forms a connection portion. [Appended Item 63] The humidifier according to appended item 62, wherein the end portion of the heating element forms an electrical contact for receiving power. [Appended Item 64] A tab having an inner portion adapted to hold liquid, A hot plate, and a heating device including a heating element provided on a first side of the hot plate, An overmold formed on the inner portion of the tab, the overmold completely surrounding the heating device such that the heating device is embedded within the overmold, and the overmold A humidifier comprising [Appended Claim 65] The humidifier according to appended claim 64, wherein the overmold comprises a thermally conductive plastic. [Appended Claim 66] The humidifier according to any one of appended claims 64 to 65, wherein the tab includes a side wall portion, and the overmold includes a side wall portion formed on the side wall portion of the tab. [Appended Claim 67] The humidifier according to any one of appended claims 64 to 66, wherein the hot plate is formed of a thermally conductive material including metal, metal alloy, aluminum, stainless steel, copper, or thermally conductive plastic. [Appended Claim 68] A tab having an inner portion adapted to hold a liquid, A heating device including a support substrate and a heating element provided on a first side of the support substrate, the support substrate being distal to the inner portion of the tab, and the heating element being proximal to the inner portion of the tab, and the heating device A first thermally conductive protective layer provided on the heating element A humidifier comprising [Appended Claim 69] The humidifier according to appended claim 68, wherein the first protective layer is overmolded to cover the heating element. [Appended Claim 70] The humidifier according to any one of appended claims 68 to 69, wherein the support substrate comprises at least one of a composite epoxy material (CEM) and a glass fiber reinforced epoxy laminate. [Appended Claim 71] The humidifier according to any one of appended claims 68 to 70, wherein the first protective layer comprises stainless steel. [Appended Claim 72] The humidifier according to any one of claims 68 to 71, further comprising an electrical insulating layer between the first protective layer and the heating element. [Claim 73] The humidifier according to any one of claims 68 to 72, further comprising a second thermally conductive protective layer provided on a second side of the support substrate and at an edge portion of the support substrate. [Claim 74] The humidifier according to any one of claims 68 to 73, wherein an end portion of the heating element is exposed from the first protective layer to provide an electrical contact for receiving power. [Claim 75] The humidifier according to any one of claims 68 to 74, wherein the heating element comprises a polymer thick film (PTF).

Explanation of reference numerals

[0100] 10 ventilator, 12 flow generator, 14 humidifier, 16 humidifier chamber, 18 lid, 20 humidifier tub, 22 tub lid, 24 channel, 26 outlet, 28 gas outlet, 30 tub bottom, bottom container, 32 bottom plate, 36, 68, 368, 468, 568, 668, 786, 868 heating device, 38 insulation layer, 40 cradle bottom, 42 electrical leads, 43 control device, 44, 70, 470, 570, 670 hot plate, 46 laminate layer, 48, 74, 248, 474, 574, 674, 974, 1074, 1174 heating element, 50 protective layer, printed protective layer, 52 electrical components, 52A thermosensor, 52B Thermofuses, 53, 54, 56, 678, 778 Contact pads, 59 Connections, 60, 360, 560 Tabs, 61 Contacts, 62, 462, 562 Water, 63 Electrical contacts, 72 Dielectric layer, 76 Protective layer, 78 Contact pads, 80 Edges, 380 Electrical contact structure, 382, 782 Spring arms, 383 IR sensors, 469, 569, 969, 1073, 1193 Protective coating, 676 Protective layer, 682 Spring-loaded electrical contacts, 780 Electrical contact structure, 785 Stubs, 990 Support substrate, 1075 Laminate layer, 1090 Support substrate, 1182 Electrical contact arms, 1183 Protective contact edges, 1190 Support substrate, 1192 Outer protective coating, 1274 Polymer thick film (PTF), 1295 copper track, copper conductor

Claims

Claim 1 a tab adapted to hold a liquid, and a heating device comprising a substrate having an etched heating track A humidifier comprising.

Images