Vaporizer mouthpiece with a positive temperature coefficient resistive heater

Abstract

To provide a vaporizer device such as a portable personal vaporizer device generating an inhalable aerosol from one or more vaporizable materials and including a heating element utilizing a semiconductive material with nonlinear positive temperature coefficient of resistivity (PTCR) and a mouthpiece.SOLUTION: A mouthpiece for a vaporizer device includes a vapor inlet and an aerosol outlet. A first plurality of air inlets and a second plurality of air inlets are disposed between the vapor inlet and the aerosol outlet and configured to provide air streams. The air streams form a first vortex and a second vortex. In the apparatus, the air streams mix with vapor entering from the vapor inlet and form an aerosol exiting through the aerosol outlet. Related systems, techniques and articles are also described.SELECTED DRAWING: Figure 39

Description

[Technical Field]

[0001] cross reference This application claims priority to U.S. Provisional Patent Application No. 62,978,236, filed February 18, 2020, entitled "Mouthpiece for Vaporizer Including Positive Temperature Coefficient of Resistivity Heater," the entire disclosure of which is incorporated herein by reference to the extent permitted by law.

[0002] Technical Field The subject matter described herein relates to vaporizer devices, such as portable personal vaporizer devices, that generate inhalable aerosols from one or more vaporizable materials and that include a heating element and a mouthpiece that utilizes a semiconductor material having a nonlinear positive temperature coefficient of resistivity (PTCR).

[0003] background Vaporizer devices, sometimes referred to as electronic vaporizer devices or e-vaporizer devices, can be used to deliver an aerosol (sometimes referred to as a "vapor") containing one or more active ingredients, via inhalation of the aerosol by a user of the vaporizer device. Electronic cigarettes, sometimes referred to as e-cigarettes, are a type of vaporizer device, typically battery-powered, and can be used to simulate a smoking experience without the combustion of tobacco or other substances. In using a vaporizer device, a user inhales the aerosol, commonly referred to as a vapor, which can be generated by a heating element that vaporizes (generally refers to at least partially transitioning a liquid or solid into the gas phase) a vaporizable material, which can be a liquid, solution, solid, wax, or any other form compatible with use of the particular vaporizer device.

[0004] To receive the inhalable aerosol generated by the vaporizer device, in some examples, a user can activate the vaporizer device by puffing, pressing a button, or by some other approach. The term puffing, as commonly used (and used herein), refers to a user inhaling, causing a volume of air to be drawn through the vaporizer device, whereby the vaporized vaporizable material and the air combine to generate the inhalable aerosol. A typical approach by which a vaporizer device (which may have, for example, an air inlet, an air outlet fluidly connected to a mouthpiece, and a vaporization chamber therebetween) generates an inhalable aerosol from a vaporizable material involves heating the vaporizable material in a vaporization chamber (sometimes called a heater chamber), thereby converting the vaporizable material to a gas (vapor) phase. The vaporization chamber generally refers to the region or volume within the vaporizer device in which a heat source heats the vaporizable material to generate a mixture of air and the vaporizable material in a state of equilibrium between the gas phase and a condensed phase (e.g., liquid and / or solid).

[0005] Certain components of the vaporizable material in the gas phase condense upon cooling and / or pressure changes after vaporization, thereby forming an aerosol containing condensed-phase (e.g., liquid and / or solid) particles suspended in at least a portion of the air drawn into the vaporizer device via the puff. When the vaporizable material includes a semi-volatile compound (e.g., a compound such as nicotine that has a relatively low vapor pressure below the inhalation temperature and pressure), the inhalable aerosol may include the semi-volatile compound in some local equilibrium between the gas phase and the condensed phase.

[0006] overview In one embodiment, a mouthpiece for a vaporizer device has a vapor inlet, an aerosol outlet, a first plurality of air inlets, and a second plurality of air inlets. The first plurality of air inlets are disposed between the vapor inlet and the aerosol outlet and are configured to provide a first plurality of air streams. The first plurality of air streams form a first vortex. The first vortex has a first axis of rotation and a first direction of rotation about the first axis of rotation. The second plurality of air inlets are also disposed between the vapor inlet and the aerosol outlet and are configured to provide a second plurality of air streams. The second plurality of air streams form a second vortex. The second vortex has a second axis of rotation and a second direction of rotation about the second axis of rotation. The first and second plurality of air streams are configured to mix with vapor flowing through the vapor inlet and form an aerosol that flows out through the aerosol outlet.

[0007] One or more of the following features may be included in any workable combination. For example, each inlet of the first plurality of air inlets may be a circular hole formed through the thickness of the mouthpiece at an angle of approximately 15 to 45 degrees from the outer surface of the mouthpiece. The interior angle of each circular hole may open toward the first rotation direction. Each inlet of the second plurality of air inlets may also be a circular hole formed through the thickness of the mouthpiece at an angle of approximately 15 to 45 degrees from the outer surface of the mouthpiece. The interior angle of each circular hole of the second plurality of air inlets may open toward the second rotation direction. The first rotation direction and the second rotation direction may be opposite directions. For example, if the first rotation direction is counterclockwise, the second rotation direction is clockwise. The first rotation axis and the second rotation axis may be non-parallel. The first and second rotation axes may create a turbulent flow in which the steam flowing into the mouthpiece from the steam inlet mixes with the incoming air. The first and second plurality of air inlets may be arranged in a plane. The first and second plurality of air inlets may each be arranged in a circle. The cross-sectional area of ​​the steam inlet may be at least four times larger than the cross-sectional area of ​​the aerosol outlet. When the steam inlet can have a steam inlet temperature, the aerosol outlet can have an aerosol outlet temperature, and the difference between the steam inlet temperature and the aerosol outlet temperature may be at least 100°C.

[0008] In another aspect, a vaporizer device includes a housing having an air inlet. The vaporizer device also includes a heating element within the housing. The heating element includes a resistive material with a nonlinear positive temperature coefficient. The vaporizer device also includes a heat exchanger thermally coupled to the heating element and positioned to receive an airflow from the air inlet. The heat exchanger is configured to transfer heat between the heating element and the airflow to generate a heated airflow. The heated airflow exiting the heat exchanger is configured to vaporize the vaporizable material. The vaporizer device also includes a mouthpiece configured to receive the vaporized vaporizable material via the vapor inlet. The mouthpiece includes a vapor inlet, an aerosol outlet, a first plurality of air inlets, and a second plurality of air inlets. The first plurality of air inlets are positioned between the vapor inlet and the aerosol outlet and configured to supply a first plurality of air flows. The first plurality of air flows form a first vortex. The first vortex has a first axis of rotation and a first direction of rotation about the first axis of rotation. A second plurality of air inlets is also disposed between the vapor inlet and the aerosol outlet and is configured to supply a second plurality of air streams. The second plurality of air streams form a second vortex. The second vortex has a second axis of rotation and a second direction of rotation about the second axis of rotation. The first and second plurality of air streams are configured to mix with the vaporized vaporizable material flowing through the vapor inlet to form an aerosol that flows out through the aerosol outlet.

[0009] One or more of the following features may be included in any workable combination. For example, each inlet of the first plurality of air inlets may be a circular hole formed through the thickness of the mouthpiece at an angle of approximately 15 to 45 degrees from the outer surface of the mouthpiece. The interior angle of each circular hole may open toward a first rotation direction. Each inlet of the second plurality of air inlets may also be a circular hole formed through the thickness of the mouthpiece at an angle of approximately 15 to 45 degrees from the outer surface of the mouthpiece. The interior angle of each circular hole of the second plurality of air inlets may open toward a second rotation direction. The first rotation direction and the second direction may be opposite directions. For example, the first rotation direction may be counterclockwise, while the second rotation direction is clockwise. The first rotation axis and the second rotation axis may be non-parallel. The first and second rotation axes may create a turbulent flow in which the steam flowing into the mouthpiece from the steam inlet mixes with the incoming air. The first and second plurality of air inlets may be arranged in a plane. The first and second plurality of air inlets may each be arranged in a circle. The cross-sectional area of ​​the steam inlet may be at least four times larger than the cross-sectional area of ​​the aerosol outlet. The steam inlet may have a steam inlet temperature, and the aerosol outlet may have an aerosol outlet temperature, and the difference between the steam inlet temperature and the aerosol outlet temperature may be at least 100°C. The heat exchanger may include a first heat exchanger thermally coupled to a first side of the heating element. The heat exchanger may include a second heat exchanger thermally coupled to a second side of the heating element. The heat exchanger may have a plurality of fin features. The heat exchanger may be made of aluminum, copper, steel, stainless steel, or titanium. The heat exchanger may be made of a thermally conductive material extrusion. The device may include a flow diverter disposed in the path of the airflow and configured to redirect a portion of the airflow through the heat exchanger. The housing may include a heater assembly cover that houses the heat exchanger. The device may include a power source configured to provide electrical energy to heat the heating element.The device may include a cartridge positioned downstream of the heating element and oriented to receive the heated airflow, where downstream refers to the airflow. The housing may include a connector configured to couple the housing to a cartridge containing a vaporizable material. The vaporizable material may be a solid vaporizable material.

[0010] The vaporizer device may have a cartridge configured to contain a vaporizable material. The cartridge may have a first air inlet. The housing may have a connector configured to couple the housing to the cartridge. The cartridge may contain a solid vaporizable material. The cartridge may have a reservoir, a liquid vaporizable material in the reservoir, and a wick fluidly connected to the liquid vaporizable material, where the cartridge is configured to receive a heated airflow and direct the heated airflow over the wick. The cartridge may have a mouthpiece, and the wick may be positioned in the airflow path between the heating element and the mouthpiece. The cartridge may have a second air inlet configured to draw a second airflow into the cartridge and mix it with the heated airflow in a heat exchanger and a condensing chamber positioned in the airflow path downstream of the vaporizable material. The cartridge may have a reservoir, a liquid vaporizable material in the reservoir, and a wick fluidly connected to the liquid vaporizable material. The wick may be configured to receive the heated airflow from the heat exchanger and generate vaporized vaporizable material in the form of a vapor and / or first aerosol. The solid vaporizable material may be configured to receive the vapor and / or first aerosol and generate a second aerosol. The mouthpiece may be configured to receive the second aerosol after the vapor and / or first aerosol has passed through the solid vaporizable material.

[0011] The vaporizer device may have a first cartridge including a vaporizable material, a first air inlet, and a wick. The vaporizable material may be a liquid vaporizable material, and the wick may be fluidly connected to the liquid vaporizable material. The wick may be configured to receive a heated airflow from the heat exchanger through the first air inlet and vaporize the vaporizable material to generate a vapor and / or a first aerosol. The vaporizer device may have a second cartridge including a solid vaporizable material and a mouthpiece. The solid vaporizable material may be configured to receive the vapor and / or first aerosol and generate a second aerosol. The mouthpiece may be configured to receive the second aerosol after the vapor and / or first aerosol has passed through the solid vaporizable material. The first cartridge may be removably coupled to the housing. The second cartridge may be removably coupled to the housing and / or the first cartridge. The first cartridge and the second cartridge may be disposable cartridges. The second cartridge may have a second air inlet for mixing ambient temperature air with the vaporized vaporizable material after it has passed through the solid vaporizable material, and the device may have a fibrous body positioned to receive and cool the vapor and / or the second aerosol after the first aerosol has passed through the solid vaporizable material.

[0012] The nonlinear positive temperature coefficient resistive material has an electrical resistivity transition zone in which the electrical resistivity increases over a temperature range, such that when the heating element is heated above a first temperature within the electrical resistivity transition zone, current from the power source is reduced to a level that limits further temperature increase of the heating element. The electrical resistivity transition zone may begin at a first temperature between 150°C and 350°C. The electrical resistivity transition zone may begin at a first temperature between 220°C and 300°C. The electrical resistivity transition zone may begin at a first temperature between 240°C and 280°C. The increase in electrical resistivity over the temperature range of the electrical resistivity transition zone may have an increase factor of at least 10, an increase factor of at least 100, or an increase factor of at least 1000. The increase factor characterizes the relative change in electrical resistivity between the electrical resistivity at a first temperature associated with the beginning of the electrical resistivity transition zone and the electrical resistivity at a second temperature associated with the end of the electrical resistivity transition zone. The electrical resistivity transition zone may begin at a first temperature, and the electrical resistivity of the heating element at temperatures below the first temperature may be between 0.2 Ω·cm and 200 Ω·cm, between 2.0 Ω·cm and 20 Ω·cm, or between 20 Ω·cm and 200 Ω·cm.

[0013] The device may include a power supply configured to supply current to the heating element at a voltage between 3 volts and 50 volts, a pressure sensor, and a controller coupled to the pressure sensor and configured to detect inhalation and, in response, electrically connect the power supply to the heating element. The housing may be cylindrical, the heating element may be cylindrical, and the heat exchanger may be cylindrical. The housing may be rectangular, the heating element may be rectangular, and the heat exchanger may be rectangular. The power supply may provide either direct current (DC) or alternating current (AC).

[0014] The vaporizer device may have an input means configured to electrically connect a power source to a PTCR heating element (PTCR heater) in response to a user input. The input means may include a push button. The PTCR heating element of the vaporizer device self-regulates to maintain a predetermined temperature when activated. The vaporizer device does not require a pressure sensor and / or a controller coupled to the pressure sensor to electrically connect a power source to the PTCR heating element and regulate its temperature.

[0015] In another aspect, a vaporizer device for vaporizing a solid vaporizable material with a heated airflow includes a housing having an air inlet and a power supply configured to provide an electric current at a voltage, and a PTCR heater assembly within the housing. The PTCR heater assembly includes a heating element within the housing and is configured to be electrically coupled to the power supply to receive the electric current. The PTCR heating element includes a PTCR material having an electrical resistivity that varies based on temperature. The electrical resistivity has an electrical resistivity transition zone where the electrical resistivity increases over a temperature range, such that when the PTCR heating element is heated above a first temperature within the transition zone, the electrical current from the power supply is reduced to a level that limits further temperature increase of the PTCR heating element. The heater assembly also includes a heat exchanger thermally coupled to the heating element and positioned to receive the airflow from the air inlet. The heat exchanger is configured to transfer heat between the heating element and the airflow to generate a heated airflow. The heated airflow exiting the heat exchanger is configured to vaporize the solid vaporizable material. The vaporizer device also includes a mouthpiece configured to receive the vaporized solid vaporizable material through the vapor inlet. The mouthpiece includes a vapor inlet, an aerosol outlet, a first plurality of air inlets, and a second plurality of air inlets. The first plurality of air inlets are disposed between the vapor inlet and the aerosol outlet and configured to provide a first plurality of air streams. The first plurality of air streams form a first vortex. The first vortex has a first axis of rotation and a first direction of rotation about the first axis of rotation. The second plurality of air inlets are also disposed between the vapor inlet and the aerosol outlet and configured to provide a second plurality of air streams. The second plurality of air streams form a second vortex. The second vortex has a second axis of rotation and a second direction of rotation about the second axis of rotation. The first plurality of air streams and the second plurality of air streams are configured to mix with the vaporized solid vaporizable material flowing through the vapor inlet and form an aerosol that flows out through the aerosol outlet.

[0016] One or more of the following features may be included in any workable combination. For example, each inlet of the first plurality of air inlets may be a circular hole formed through the thickness of the mouthpiece at an angle of approximately 15 to 45 degrees from the outer surface of the mouthpiece. The interior angle of each circular hole may open toward a first rotation direction. Each inlet of the second plurality of air inlets may also be a circular hole formed through the thickness of the mouthpiece at an angle of approximately 15 to 45 degrees from the outer surface of the mouthpiece. The interior angle of each circular hole of the second plurality of air inlets may open toward a second rotation direction. The first rotation direction and the second direction may be opposite directions. For example, the first rotation direction may be counterclockwise, while the second rotation direction is clockwise. The first rotation axis and the second rotation axis may be non-parallel. The first and second rotation axes may create a turbulent flow in which the steam flowing into the mouthpiece from the steam inlet mixes with the incoming air. The first and second plurality of air inlets may be arranged in a plane. The first and second plurality of air inlets may each be arranged in a circle. The cross-sectional area of ​​the vapor inlet may be at least four times larger than the cross-sectional area of ​​the aerosol outlet. When the vapor inlet can have a vapor inlet temperature, the aerosol outlet has an aerosol outlet temperature, and the difference between the vapor inlet temperature and the aerosol outlet temperature may be at least 100°C. A solid vaporizable material may be included with the vaporizer device. The solid vaporizable material may be a tobacco-containing medium. The vaporizer device may have an input means configured to electrically connect a power source to the PTCR heating element in response to a user input. The input means may include a push button. The vaporizer device may not have a controller. The vaporizer device may not have a pressure sensor. In another embodiment, the vaporizer device has a pressure sensor and a controller coupled to the pressure sensor and configured to detect inhalation and, in response, electrically connect a power source to the PTCR heating element. The heat exchanger may include a first heat exchanger thermally coupled to a first side of the heating element. The heat exchanger may include a second heat exchanger thermally coupled to a second side of the heating element. The heat exchanger may include a plurality of fin features.The heat exchanger may be made of aluminum, copper, steel, stainless steel, or titanium. The heat exchanger may be made of a thermally conductive material extrusion. The heat exchanger may be made of a metal foam, such as aluminum foam. The PTCR heater assembly may have a heater assembly cover. The heater assembly cover may comprise a non-conductive material. The heater assembly cover may comprise a metal with a non-conductive coating that insulates the heater assembly cover from the heat exchanger. The heater assembly cover may comprise polytetrafluoroethylene (PTFE).

[0017] The electrical resistivity transition zone may begin at a first temperature between 150°C and 350°C. The electrical resistivity transition zone may begin at a first temperature between 220°C and 300°C. The electrical resistivity transition zone may begin at a first temperature between 240°C and 280°C. The first temperature may be greater than 225°C. The PTCR heating element may be heated to an operating temperature between 240°C and 280°C. The PTCR heating element may be heated to an operating temperature between 245°C and 255°C. The PTCR heating element may be heated to an operating temperature of about 250°C. The PTCR heater assembly may increase the electrical resistivity by at least a factor of increase of 10, at least a factor of increase of 100, or at least a factor of increase of 1000 over the temperature range of the electrical resistivity transition zone. The factor of increase characterizes the relative change in electrical resistivity between the electrical resistivity at a first temperature associated with the beginning of the electrical resistivity transition zone and the electrical resistivity at a second temperature associated with the end of the electrical resistivity transition zone. The electrical resistivity transition zone may begin at a first temperature and end at a second temperature, where the difference between the first and second temperatures is no more than 500° C., no more than 200° C., no more than 100° C., or no more than 50° C. The electrical resistivity transition zone may begin at the first temperature, where the electrical resistivity of the PTCR heating element at temperatures below the first temperature is between 0.2 Ω·cm and 2.0 Ω·cm, between 2.0 Ω·cm and 20 Ω·cm, or between 20 Ω·cm and 200 Ω·cm.

[0018] In another aspect, a method for vaporizing a vaporizable material includes receiving user input with a vaporizer device and heating an airflow using a PTCR heater assembly including a heat exchanger thermally coupled to a PTCR heating element to generate a heated airflow. The PTCR heating element is configured to be electrically coupled to a power source. The PTCR heating element has an electrical resistivity that varies based on temperature. The electrical resistivity has an electrical resistivity transition zone including an increase in electrical resistivity over a temperature range from a first temperature to a second temperature, such that when the PTCR heating element is heated between the first and second temperatures, current from the power source is reduced to a level that limits further temperature increase of the PTCR heating element due to the current. The method also includes vaporizing the vaporizable material with the heated airflow. The vaporizable material may include nicotine.

[0019] The details of one or more variations of the subject matter described herein are set forth in the accompanying drawings and the description below. Other features and advantages of the subject matter described herein will be apparent from the description and drawings, and from the claims. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 1 shows the behavior of thermal power generation in an isotropic PTCR material. [Figure 2] FIG. 1 is a block diagram illustrating an exemplary vaporizer device according to some embodiments of the present subject matter that can provide uniform heating of vaporizable material utilizing convection heating. [Figure 3] FIG. 1 is a block diagram illustrating an exemplary vaporizer device and cartridge containing a liquid vaporizable material that can provide uniform heating of the vaporizable material using convection heating. [Figure 4] 1 is a cross-sectional view of an exemplary vaporizer device containing a liquid vaporizable material. [Figure 5] 1 is a cross-sectional view of an exemplary vaporizer device containing a solid vaporizable material (e.g., a non-combustion heated product). [Figure 6] FIG. 1 is a block diagram illustrating an exemplary vaporizer device and cartridge containing liquid and solid vaporizable materials that can provide uniform heating of the vaporizable materials using convection heating. [Figure 7] FIG. 1 is a block diagram illustrating an exemplary vaporizer device with multiple cartridges. [Figure 8] 1 is a cross-sectional view of an exemplary vaporizer device that includes both a liquid vaporizable material and a solid vaporizable material. [Figure 9] FIG. 1 is a plot illustrating an exemplary resistivity versus temperature curve for a nonlinear positive temperature coefficient of resistivity (PTCR) material. [Figure 10] FIG. 10 depicts a table of resistivity versus temperature curve data for the nonlinear PTCR semiconductor material shown in FIG. 9. [Figure 11] FIG. 1 is a plot illustrating an exemplary resistivity versus temperature curve for a nonlinear positive temperature coefficient of resistivity (PTCR) material. [Figure 12A] FIG. 1 illustrates an exemplary PTCR heating element that can enable improved heating of the vaporizer. [Figure 12B] FIG. 9B is a cross-sectional view of the exemplary PTCR heating element shown in FIG. 9A. [Figure 13A] FIG. 1 illustrates a temperature model of an exemplary PTCR heater. [Figure 13B] FIG. 1 illustrates a temperature model of an exemplary PTCR heater. [Figure 13C] FIG. 1 illustrates a temperature model of an exemplary PTCR heater. [Figure 13D] FIG. 1 illustrates a temperature model of an exemplary PTCR heater. [Figure 13E] FIG. 1 illustrates a temperature model of an exemplary PTCR heater. [Figure 14A] FIG. 1 illustrates a temperature model of an exemplary PTCR heater. [Figure 14B] FIG. 1 illustrates a temperature model of an exemplary PTCR heater. [Figure 14C] FIG. 1 illustrates a temperature model of an exemplary PTCR heater. [Figure 14D]FIG. 1 illustrates a temperature model of an exemplary PTCR heater. [Figure 14E] FIG. 1 illustrates a temperature model of an exemplary PTCR heater. [Figure 14F] FIG. 1 illustrates a temperature model of an exemplary PTCR heater. [Figure 15] FIG. 10 illustrates a temperature model of an exemplary heater after 6.0 seconds of voltage application under free convection conditions. [Figure 16A] FIG. 10 illustrates an exemplary heater surface temperature model as a function of time. [Figure 16B] FIG. 10 illustrates a model of the measured maximum surface temperature of an exemplary heater as a function of time. [Figure 16C] FIG. 10 illustrates a model of the measured average surface temperature of an exemplary heater as a function of time. [Figure 17] FIG. 10 illustrates the transient current response of an exemplary heater as a function of time. [Figure 18] FIG. 1 is a perspective view illustrating an exemplary vaporizer assembly including a PTCR heater and a heat exchanger member that can enable improved convective heating and uniform heating of the vaporizable material. [Figure 19] 1 is an exploded view of a rectangular PTCR vaporization device, including an exploded view of an exemplary vaporizer assembly. [Figure 20] FIG. 1 is a perspective view of an exemplary PTCR vaporization assembly. [Figure 21] 1 is a perspective view of an exemplary PTCR vaporization assembly and a rectangular disposable product. [Figure 22] FIG. 1 is a perspective view of an exemplary PTCR vaporization assembly and a rectangular disposable product 0.2 seconds after activation. [Figure 23] FIG. 1 is a perspective view of an exemplary PTCR vaporization assembly and a rectangular disposable product 0.5 seconds after activation. [Figure 24] FIG. 1 is a perspective view of an exemplary PTCR vaporization assembly and a rectangular disposable product 1.0 seconds after activation. [Figure 25]FIG. 1 is a perspective view of an exemplary PTCR vaporization assembly and a rectangular disposable product 2.0 seconds after activation. [Figure 26] FIG. 1 is a perspective view of an exemplary PTCR vaporization assembly and a rectangular disposable product 3.0 seconds after activation. [Figure 27] FIG. 1 is a perspective view of an exemplary PTCR heater having a cylindrical geometry. [Figure 28] FIG. 1 is an exploded view of an exemplary cylindrical PTCR heater. [Figure 29] FIG. 1 is a perspective view of an exemplary assembled PTCR heater. [Figure 30] FIG. 1 is a perspective view of an exemplary PTCR vaporization device with the outer cover and cylindrical flow diverter removed. [Figure 31] FIG. 1 is a perspective view of an exemplary PTCR vaporization device. [Figure 32] FIG. 1 is a plot showing the logarithm of resistivity as a function of temperature for an exemplary cylindrical vaporization device with a PTCR heater. [Figure 33] FIG. 10 is a cross-sectional plot illustrating a temperature simulation of an exemplary embodiment of a cylindrical vaporizer device with a PTCR heater. [Figure 34A] FIG. 10 is a cut plot showing the temperature transient response of an exemplary implementation of a cylindrical vaporization device with a PTCR heater in color. [Figure 34B] FIG. 10 is a cut plot showing the temperature transient response of an exemplary implementation of a cylindrical vaporization device with a PTCR heater, using color. [Figure 34C] FIG. 10 is a cut plot showing the temperature transient response of an exemplary implementation of a cylindrical vaporization device with a PTCR heater in color. [Figure 34D] FIG. 10 is a cut plot showing the temperature transient response of an exemplary implementation of a cylindrical vaporization device with a PTCR heater in color. [Figure 34E] FIG. 10 is a cut plot showing the temperature transient response of an exemplary implementation of a cylindrical vaporization device with a PTCR heater in color. [Figure 34F]FIG. 10 is a cut plot showing the temperature transient response of an exemplary implementation of a cylindrical vaporization device with a PTCR heater in color. [Figure 34G] FIG. 10 is a cut plot showing the temperature transient response of an exemplary implementation of a cylindrical vaporization device with a PTCR heater in color. [Figure 35] 1A and 1B are perspective and end views of a mouthpiece having multiple air inlets. [Figure 36] FIG. 1 is a perspective view of a mouthpiece attached to a rectangular PTCR vaporization assembly. [Figure 37] FIG. 1 is a perspective view of a mouthpiece attached to a rectangular PTCR vaporizing assembly showing the airflow and temperature patterns without the actuating air inlet. [Figure 38] FIG. 1 is a perspective end view looking through the aerosol outlet of a mouthpiece with multiple air inlets showing the airflow pattern. [Figure 39] FIG. 1 is a perspective view of a mouthpiece attached to a rectangular PTCR vaporizing assembly showing the airflow and temperature patterns 0.1 seconds after activation. [Figure 40] FIG. 1 is a perspective view of a mouthpiece attached to a rectangular PTCR vaporizing assembly showing the airflow and temperature patterns 0.2 seconds after activation. [Figure 41] FIG. 1 is a perspective view of a mouthpiece attached to a rectangular PTCR vaporizing assembly showing the airflow and temperature patterns 0.3 seconds after activation. [Figure 42] FIG. 1 is a perspective view of a mouthpiece attached to a rectangular PTCR vaporizing assembly showing the airflow and temperature patterns 0.4 seconds after activation. [Figure 43] FIG. 1 is a perspective view of a mouthpiece attached to a rectangular PTCR vaporizing assembly showing the airflow and temperature patterns 0.5 seconds after activation. [Figure 44] FIG. 1 is a perspective view of a mouthpiece attached to a rectangular PTCR vaporizing assembly showing the airflow and temperature patterns 1.0 seconds after activation. [Figure 45]FIG. 1 is a perspective view of a mouthpiece attached to a rectangular PTCR vaporizing assembly showing the airflow and temperature patterns 2.0 seconds after activation. [Figure 46] FIG. 1 is a perspective view of a mouthpiece attached to a rectangular PTCR vaporizing assembly showing the airflow and temperature patterns 3.0 seconds after activation. [Figure 47] FIG. 10 illustrates the temperature of air exiting the mouthpiece of an exemplary vaporizer device including a PTCR heater as a function of time. [Figure 48] FIG. 10 illustrates the current response as a function of time of an exemplary vaporizer device including a PTCR heater. [Figure 49] FIG. 1 is a top view of a mouthpiece attached to a rectangular PTCR vaporization assembly showing the current density in the PTCR heater as a function of cool ambient airflow entering the PTCR heater assembly.

[0021] Wherever possible, like reference numbers in the drawings refer to like elements.

[0022] Detailed Description Some aspects of the present subject matter relate to vaporizer heaters that utilize a nonlinear resistivity positive temperature coefficient of resistance (PTCR) heating element, also known as a PTCR heater, for use as a convection heater. In such convection heaters for vaporizers, air is heated by a heating element and passed over or through a vaporizable material to form a vapor and / or aerosol for inhalation. In embodiments, the vaporizable material may include a solid vaporizable material (e.g., loose-leaf material commonly used in heat-not-burn (HNB) vaporizers) and / or a liquid vaporizable material (e.g., pre-filled cartridges, pods, etc.). PTCR heating elements used for convection heating can enable more uniform heating of the vaporizable material. Improved uniformity in heating can provide many benefits, including avoiding different temperatures within the vaporizable material acting as an insulator, preventing contamination of the heating element, etc. Additionally, because the heating element can be formed from a PTCR material, the heating element can self-limit its temperature and will not heat above a certain temperature when a known range of voltage is applied, thereby avoiding the formation of unwanted and potentially dangerous chemical by-products.

[0023] The generation of thermal power within an isotropic PTCR material may be characterized by the fact that for all control volumes ∂x, ∂y, ∂z within the isotropic PTCR material in response to a voltage gradient ∇V, the control volumes ∂x, ∂y, ∂z heat to a temperature within the PTCR transition region and maintain that temperature within a wide range of ∇V, as shown in Figure 1. The generation of thermal power is

number

[0024] By utilizing a PTCR heating element, some embodiments can allow for temperature control over a range of applied voltages without the need for temperature sensors, electronic circuitry, microprocessors and / or algorithms to provide power control to the heating element.

[0025] As used herein, the term "solid vaporizable material" generally refers to vaporizable materials, including solid materials. For example, some vaporizer devices heat materials derived from plant leaves or other plant components to extract the plant's characteristic flavor aromas and other products as vapor. These plant materials may be chopped and blended with various plant products, including tobacco, into a homogenized assimilate, which produces nicotine and / or nicotine compounds and can be delivered to users of such vaporizer devices in the form of an aerosol. The homogenized assimilate may contain vaporizable liquids, such as propylene glycol and glycerol, to improve vapor density and the aerosol produced when heated. To avoid the production of undesirable harmful or potentially harmful components (HPHCs), this type of vaporizer device benefits from a heater with temperature control means. Such vaporizer devices, which heat the plant leaves or homogenized assimilate described above to maintain temperatures below combustion levels, are commonly referred to as heat-not-burn (HNB) devices.

[0026] As used herein, the term liquid vaporizable material generally refers to vaporizable material that does not include solid material. The liquid vaporizable material may include, for example, a liquid, a solution, a wax, or any other form that may be compatible with use in a particular vaporizer device. In embodiments, the liquid vaporizable material may include any form suitable for utilizing a wick or wick member that draws the vaporizable material into the vaporization chamber. The liquid vaporizable material may include plant-derived ingredients such as nicotine and / or nicotine compounds. The liquid vaporizable material may include vaporizable liquids such as propylene glycol and glycerol.

[0027] Vaporizer devices operate by heating vaporizable material to an appropriate temperature to generate an aerosol, but do not burn or carbonize the vaporizable material. Some types of vaporizer devices are more sophisticated in that they utilize relatively tight temperature control to prevent overheating and the associated formation of HPHCs. This sophistication, which typically requires electronic circuitry including a microprocessor, is typically difficult in HNB devices due to the inherent non-uniformity and associated spatially inconsistent thermal properties of the heated vaporizable material. This can result in regions of overheating and the potential for HPHC formation. Some existing solutions are unable to control local temperatures within the vaporizer device, resulting in regions of overheating of the vaporizable material and a higher probability of HPHC formation.

[0028] Another type of vaporizer device is simpler in that no temperature control means are provided, which may make the vaporizer device cheaper to construct, but carries the risk of overheating, which can result in the production of undesirable chemical by-products.

[0029] In HNB vaporizer devices (e.g., where the vaporizable material is solid), some existing methods lack the ability to impose a uniform temperature for one or more of the following reasons: For example, the solid vaporizable material to be heated has a low thermal diffusivity, which can slow the diffusion of high temperatures from the heating element to the solid vaporizable material, resulting in large temperature gradients. As a result, non-uniform heating can be an unavoidable outcome. As another example, when temperature control of the heating element is employed, the temperature control of the heating element typically addresses the average temperature, which can result in non-uniform heating of the solid vaporizable material via the high temperature within the heating element, resulting in high temperatures within the solid vaporizable material. As yet another example, to enable heating of insulating materials, some existing HNB devices require a pre-heating time that can be 30 seconds or more, which entails costs in both energy consumption and battery depletion, as well as user inconvenience.

[0030] In vaporizer devices that vaporize fluids by contacting a heating element with the fluid to be vaporized, contamination of the heating element can occur, leading to potential performance loss. A solution to this problem may be to incorporate the heating element into the disposable part of the vaporizer, whereby the heating element is replaced with each new disposable part, limiting but not eliminating contamination of the heating element.

[0031] To overcome the difficulty of uniformly heating the vaporizable material, some embodiments of the present subject matter can provide air preheating using one or more PTCR heating elements in conjunction with a heat exchanger. When a user draws air into the vaporizer device, the incoming airflow is heated to a controlled temperature because it passes over the heat exchanger before passing through or over the vaporizable material to be heated. The vaporizable material can be a solid material (e.g., HNB material) or a liquid (e.g., a fluid containing a porous wick). In embodiments, the airflow can pass over the heat exchanger, then over and / or through a porous wick impregnated with the liquid vaporizable material, then through the solid vaporizable material (e.g., HNB material), and then reach the user. In embodiments, a geometry for the inflow of cooled air, such as a balance air inlet (i.e., a second air inlet), can be included between the wick and the user. Additionally, the present subject matter can provide a PTCR heater with an inherent temperature control means, which can ensure that the designed peak temperature is not exceeded for a given range of supply voltage (variable by a factor of 10 or more in some embodiments). Such an approach can result in improved, uniform heating of the vaporizable material compared to some conventional approaches.

[0032] Furthermore, with this convection heating approach, the PTCR heating element can be located upstream of the wick, fluid container, and / or vaporizable material, thereby completely removing the PTCR heating element from any disposable parts of the mechanism. By including the PTCR heating element in the non-disposable portion of the vaporizer device, unnecessary waste can be avoided.

[0033] 2 is a block diagram illustrating an exemplary vaporizer device 100 according to some embodiments of the present subject matter that can provide uniform heating of vaporizable material using convective heating. The exemplary vaporizer device 100 has an air inlet 105, a PTCR heater 110 with a heat exchanger, and a power source 115, such as a battery, a capacitor, and / or the like. The exemplary vaporizer device 100 can include a housing 120 that can be coupled to one or more of the PTCR heater 110 with a heat exchanger and the power source 115. In embodiments, the exemplary vaporizer device 100 can include an optional controller 102 and an optional pressure sensor 107. In embodiments, the housing 120 can define the air inlet 105.

[0034] The PTCR heater 110 with a heat exchanger may have a heating element formed from a PTCR material, as described in more detail below. The heat exchanger may be thermally coupled to the heating element and configured to transfer heat between the heating element and an airflow passing over and / or through the PTCR heater 110 with a heat exchanger to generate a heated airflow. The PTCR heater 110 with a heat exchanger may have multiple heat exchangers coupled to different sides of the heating element, for example, and may have flow diverters that redirect the airflow through and / or over the fins of the heat exchangers to improve heat transfer. A more detailed description of an exemplary PTCR heater 110 with a heat exchanger is found below with reference to FIGS. 9-34G.

[0035] The exemplary vaporizer device 100 may have a connector 117 (shown in FIGS. 4, 5, and 8) for coupling the housing 120 to one or more cartridges 125 containing vaporizable material 130. In embodiments, the cartridge 125 may include a mouthpiece 135. In embodiments, the coupling is detachable, such that the cartridge 125 may be easily attached or detached from the vaporizer device 100 by a user via the connector 117.

[0036] When the vaporizer device 100 is coupled to the cartridge 125, the vaporizer device 100 and the cartridge 125 may be arranged to define an airflow path such that the airflow path passes from the air inlet 105, through and / or over the PTCR heater with heat exchanger, through the first air inlet of the cartridge, through the vaporizable material 130, and out the mouthpiece 135.

[0037] An optional controller 102 (e.g., a processor capable of executing logic, circuitry, etc.) for controlling the delivery of heat to convert the vaporizable material from a condensed form (e.g., a solid, liquid, solution, suspension, at least partially a portion of raw plant material, etc.) to a gas phase. The optional controller may be part of one or more printed circuit boards (PCBs) consistent with certain embodiments of the present subject matter.

[0038] The power supply 115 may include any power source suitable for powering the PTCR heater with heat exchanger 110. For example, the power supply 115 may include a battery, a capacitor (with resistor-capacitor (RC) damping), and / or the like. In some embodiments, the power supply 115 may provide a wide range of selectable voltages. For example, in some embodiments, the power supply 115 may provide a voltage from 3 volts to 50 volts or more. In some embodiments, the voltage provided to the PTCR heater with heat exchanger 110 is variable by an order of magnitude with little effect on the performance of the PTCR heater with heat exchanger 110. In some embodiments, the power supply 115 may include multiple power sources that are selectable based on operating conditions and / or desired vaporizer device performance.

[0039] In operation, a user can inhale (e.g., puff) air through mouthpiece 135, which can be detected by optional controller 102 using optional pressure sensor 107. In response to detecting a puff, optional controller 102 can provide current from power supply 115 to PTCR heater with heat exchanger 110, thereby heating PTCR heater with heat exchanger 110. Because PTCR heater with heat exchanger 110 is formed from PTCR material, heating is self-limiting and the heating element will not overheat.

[0040] The airflow passes through air inlet 105 and over and / or through PTCR heater 110, which includes a heat exchanger, thereby uniformly heating the air within the airflow. The heated airflow continues to vaporize material 130, which also uniformly heats vaporizable material 130 and forms a vapor (gas). Vaporizable material 130 may include a liquid, solution, solid, wax, or any other form. In some embodiments, the incoming air passing along the airflow path passes over, through, or in a region or chamber (e.g., a nebulizer) where vapor-phase vaporizable material is entrained in the air.

[0041] The entrained gas-phase vaporizable material may condense as it passes through the remaining airflow path, thereby delivering an inhalable dose of the vaporizable material in aerosol form to mouthpiece 135 for inhalation by the user in the form of vapor and / or aerosol. In some embodiments, cartridge 125 has a balancing air inlet (i.e., second air inlet) 140 that can be used to supply ambient temperature air for mixing with the heated airflow entering the cartridge through the first air inlet. The ambient temperature air can be mixed with the heated airflow in the condensation chamber. Balancing air inlet 140 is located after the heated airflow has passed through the vaporizable material (e.g., downstream of the heat exchanger and the vaporizable material), thereby cooling the heated airflow prior to inhalation by the user. In some embodiments, balancing air inlet 140 is integrated with mouthpiece 135.

[0042] Activation of the PTCR heating element may occur through detection of user interaction with one or more input devices (such as a button on the vaporizer or another tactile control device, e.g., a manual toggle switch, a push button switch, a pressure switch, etc.), in response to receiving a signal from a computing device in communication with the vaporizer, and / or through another approach to determining that a puff is occurring or about to occur, automatic detection of a puff based on one or more signals generated by one or more sensors, such as an optional pressure sensor 107, or a sensor positioned to detect pressure along the airflow path relative to ambient pressure (or optionally to measure changes in absolute pressure), one or more motion sensors on the vaporizer, one or more flow sensors on the vaporizer, a capacitive lip sensor on the vaporizer, etc.

[0043] As alluded to above, a vaporizer consistent with embodiments of the present subject matter may be configured to connect (e.g., wirelessly or via a wired connection) to a computing device (or any two or more devices) that communicates with the vaporizer. To this end, optional controller 102 may have communications hardware. Optional controller 102 may also have memory. The computing device may be a component of a vaporizer system that also includes the vaporizer and may have its own communications hardware that can establish a wireless communications channel with the vaporizer's communications hardware. For example, a computing device used as part of a vaporizer system may include a general-purpose computing device (e.g., a smartphone, tablet, personal computer, or some other portable device, such as a smartwatch) that executes software to generate a user interface that allows a user of the device to interact with the vaporizer. In another embodiment of the present subject matter, such a device used as part of a vaporizer system may be a dedicated component, such as a remote control or another wireless or wired device, having one or more physical or soft interface controls (e.g., configurable on a screen or other display device and selectable via user interaction with a touch-sensitive screen or some other input device, such as a mouse, pointer, trackball, cursor buttons, etc.). The vaporizer may include one or more output mechanisms or devices for providing information to the user.

[0044] A computing device that is part of the vaporizer system defined above may be used for any one or more functions, such as dose control (e.g., dose monitoring, dose setting, dose limiting, user tracking, etc.), controlling sessioning (e.g., session monitoring, session setting, session limiting, user tracking, etc.), controlling nicotine delivery (e.g., switching between vaporizable nicotine and non-nicotine materials, adjusting the amount of nicotine delivered, etc.), obtaining location information (e.g., locations of other users, locations of retail / commercial establishments, locations of inhalation, relative or absolute location of the vaporizer itself, etc.), personalizing the vaporizer (e.g., naming the vaporizer, locking / password protecting the vaporizer, adjusting one or more parental controls, associating the vaporizer with a user group, registering the vaporizer with the manufacturer or warranty / maintenance organization, etc.), participating in social activities with other users (e.g., games, social media communication, interacting with one or more groups, etc.), etc. The terms "sessioning," "session," "vaporizer session," or "vaporization session" are generally used to refer to a period devoted to vaporizer use. The period may include a time period, a number of doses, a quantity of vaporizable material, and / or the like.

[0045] In an example where a computing device provides signals related to activation of the PTCR heating element, or in another example of a coupling between a computing device and a vaporizer for various control or other functionality embodiments, the computing device executes one or more sets of computer instructions to provide a user interface and underlying data processing. In one example, upon detection by the computing device of a user's interaction with one or more user interface members, the computing device can send a signal to the vaporizer, thereby activating the PTCR heating element to a full operating temperature for generating an inhalable dose of vapor / aerosol. Other functions of the vaporizer can be controlled on a computing device in communication with the vaporizer through user interaction with the user interface.

[0046] The temperature of a vaporizer's PTCR heating element can depend on several factors, including conductive heat transfer to other parts of the electronic vaporizer and / or the environment, latent heat loss due to vaporization of the vaporizable material from the wick member and / or the entire atomizer, and convective heat loss due to airflow (e.g., air traversing the heating element or the entire atomizer when a user inhales on the electronic vaporizer). As described above, to ensure activation of the PTCR heating element or heating the PTCR heating element to a desired temperature, in some embodiments of the present subject matter, the vaporizer can use a signal from an optional pressure sensor 107 to determine when a user is inhaling. The optional pressure sensor 107 can be positioned within and / or connected (e.g., by a passageway or other path) to an airflow path connecting an air inlet 105 through which air enters the device and an outlet (e.g., mouthpiece 135) through which the user inhales the resulting vapor and / or aerosol, thereby causing the optional pressure sensor to detect pressure changes simultaneously with air passing through the vaporizer device from the air inlet 105 to the air outlet. In embodiments of the present subject matter, the PTCR heating element may optionally be activated by an optional pressure sensor 107 that detects a pressure change in the airflow path, for example, in association with a user's puff, e.g., by automatic puff detection. In embodiments, a switch is an input device that may be used to electrically complete a circuit between a power source and the PTCR heating element. In embodiments, input devices including relays, solenoids, and / or solid state devices may be used to electrically complete a circuit between a power source and the PTCR heating element, thereby activating the vaporizer device.

[0047] Typically, the optional pressure sensor 107 (as well as any other sensors) may be located on or coupled to (e.g., electrically or electronically connected, either physically or via a wireless connection) the optional controller 102 (e.g., a printed circuit board assembly or another type of circuit board). To ensure accurate measurements and maintain vaporizer durability, it may be beneficial to provide a resilient seal that isolates the airflow path from other portions of the vaporizer. The seal, which may be a gasket, may be configured to at least partially surround the optional pressure sensor 107, thereby isolating the connection of the optional pressure sensor 107 to the vaporizer's internal circuitry from the portion of the optional pressure sensor 107 exposed to the airflow path. In one example of a cartridge-type vaporizer, the seal or gasket may isolate a portion of one or more electrical connections between the vaporizer body and the vaporizer cartridge. Such placement of gaskets or seals within a vaporizer can be useful to mitigate potentially destructive effects on vaporizer components due to interaction with environmental factors, such as water in the vapor or liquid phase, other fluids, such as vaporizable materials, and / or to reduce air leakage from the designed airflow path within the vaporizer. Unwanted air, liquid, or other fluids passing through and / or contacting the vaporizer circuitry can cause various undesirable effects, such as altered pressure readings, and / or result in the accumulation of undesirable materials, such as moisture, vaporizable materials, on portions of the vaporizer, which can result in poor pressure signals, degradation of any pressure sensors or other components, and / or a shortened vaporizer lifespan. Leaks in seals or gaskets can also result in a user inhaling air that has passed through portions of the vaporizer device containing or made of materials that may be undesirable to inhale.

[0048] In embodiments, cartridge 125 may include a fabric body for cooling the heated airflow after it passes through vaporizable material 130 .

[0049] As described above, the vaporizable material 130 may include a solid vaporizable material (e.g., an HNB material) and / or a liquid vaporizable material (e.g., a liquid, solution, etc.). FIG. 3 is a block diagram of an exemplary vaporizer device 100 that can utilize convection heating to provide uniform heating of the vaporizable material and a cartridge 125 containing a liquid vaporizable material. The vaporizable material 130 includes an atomizer having a porous wick 150 fluidly connected to a fluid tank or reservoir 145. The porous wick 150 is positioned in the path of a heated airflow between the PTCR heater 110 with a heat exchanger and the mouthpiece 135. The porous wick 150 is positioned such that, during operation, a heated airflow passes over and / or through the vaporizable fluid-impregnated porous wick 150, causing vaporization of the liquid vaporizable material impregnated in the porous wick 150, thereby forming a vapor and / or an aerosol. In embodiments, the porous wick 150 may allow air to flow into the reservoir 145 to replace the removed liquid volume. In other words, capillary action draws the liquid vaporizable material into the wick 150 where it is vaporized by the heated airflow; in some embodiments of the present subject matter, the air may return through the wick to the reservoir 145, at least partially equalizing the pressure within the reservoir 145. Other approaches that allow air to return to the reservoir 145 to equalize pressure are also within the scope of the present subject matter. FIG. 4 is a cross-sectional view of an exemplary vaporizer device containing a liquid vaporizable material, and FIG. 5 is a cross-sectional view of an exemplary vaporizer device containing a solid vaporizable material (e.g., an HNB product).

[0050] In some embodiments, the vaporizable material 130 may include both liquid and solid vaporizable material. For example, FIG. 6 is a block diagram of an exemplary vaporizer device 100 that can utilize convective heating to provide uniform heating of the vaporizable material and a cartridge 125 that includes both liquid and solid vaporizable material. The vaporizable material 130 includes a reservoir 145 containing the liquid vaporizable material therein, a wick 150 fluidly connected to the liquid vaporizable material, and a solid vaporizable material 155 disposed downstream (with respect to the airflow) of the porous wick 150. The porous wick 150 is positioned to receive heated airflow from the heater 110 with a heat exchanger, thereby vaporizing the vaporizable material and generating a vapor and / or a first aerosol. The solid vaporizable material 155 is positioned to receive the vapor and / or first aerosol from the wick, thereby generating a second aerosol. Mouthpiece 135 is configured to receive the second aerosol after the vaporized vaporizable material has passed through solid vaporizable material 155. By combining both liquid and solid vaporizable materials, improved flavoring can be achieved. Furthermore, by utilizing convection heating through the PTCR material to vaporize both the liquid and solid vaporizable materials, only a single heater is required to heat both materials.

[0051] In some embodiments, the liquid vaporizable material and the solid vaporizable material may be contained in different cartridges. For example, FIG. 7 is a block diagram of an exemplary vaporizer device 100 with multiple cartridges. A first cartridge 605 contains the liquid vaporizable material (including a reservoir 145 and a porous wick 150), and a second cartridge 610 contains the solid vaporizable material 130, which can provide uniform heating of the vaporizable material using convection heating. The first cartridge 605 can be removably coupled to the vaporizer device 100, and the second cartridge 610 can be removably coupled to the first cartridge 605. As shown, the first cartridge 605 includes a reservoir 145 (e.g., a tank), the liquid vaporizable material in the reservoir 145, and the wick 150 in fluid communication with the liquid vaporizable material. When the first cartridge 605 is coupled to the vaporizer device 100, the wick 150 is configured to receive a heated airflow from the heater 110 with a heat exchanger, thereby vaporizing the vaporizable material to generate a vapor and / or a first aerosol. The second cartridge 610 includes a solid vaporizable material 130, a balancing air inlet 140, and a mouthpiece 135. When the second cartridge 610 is coupled to the first cartridge, the solid vaporizable material 130 is configured to receive the vapor and / or first aerosol from the wick 150 and generate a second aerosol. The mouthpiece 135 is configured to receive the second aerosol after the vapor and / or first aerosol has passed through the solid vaporizable material 155. In some embodiments, the balancing air inlet (i.e., the second air inlet) 140 can provide ambient temperature air to cool the heated second aerosol that has passed through the solid vaporizable material 155. FIG. 8 is a cross-sectional view of an exemplary vaporizer device that includes both liquid and solid vaporizable materials.

[0052] This convective heating approach can offer several advantages over traditional conduction-based heating approaches for vaporizing solid materials (e.g., HNB materials). For example, instead of poor conduction perpendicular to the airflow into an insulating material (e.g., a solid vaporizable material), which results in different porosities between the volatile material and the vaporizable material being heated, some embodiments of the present subject matter can provide preheated inlet air that flows uniformly through the vaporizable material as waves that uniformly cover the cross-section of the vaporizable material. In this case, the volatile material is released in a direction parallel to the heated airflow simultaneously with the increased porosity. As another example, because the uniform release of volatile material across the cross-section and the increased porosity occur simultaneously, some embodiments can eliminate the problem of flow path differences. As yet another example, some embodiments of the present subject matter can eliminate the problem of reduced conductive heat transfer through the product. As yet another example, some embodiments of the present subject matter can eliminate the previously required preheating period, allowing the present subject matter to provide an aerosol from heated vaporizable material on demand.

[0053] This convection heating approach can similarly offer several advantages with respect to vaporizing liquid vaporizable materials. For example, instead of directly applying heat to the liquid vaporizable material using a heater element in direct contact with the liquid vaporizable material, some embodiments of the present subject matter can provide preheated incoming air as waves that evenly cover the cross-section of a porous wick impregnated with the fluid to be vaporized, thereby avoiding temperature differences and potential contamination of the heating element.

[0054] As another example, by placing the wick very close to and upstream (with respect to the airflow) of the solid vaporizable material (e.g., loose-leaf tobacco), undesirable aerosol condensation within the device can be minimized.

[0055] Additionally, the inherent temperature control operation of PTCR heaters simplifies the power supply circuitry because no specific thermal feedback is required. The power supply circuitry to PTCR heaters can be further simplified by eliminating the need for a power supply to provide a relatively constant voltage, which is typical of power supply systems. In embodiments, the applied voltage can be varied by more than two orders of magnitude without significantly affecting the resulting heater element temperature.

[0056] An exemplary PTCR heater will now be described in more detail. PTCRs comprise semiconductor materials with electrical resistivity that changes nonlinearly with increasing temperature. Typical PTCR materials have relatively low resistivity while temperatures remain below a temperature transition zone. Above the temperature transition zone, the resistivity of the PTCR material becomes higher than the resistivity of the same PTCR material at temperatures below the temperature transition zone. The change in resistivity can increase by orders of magnitude over a temperature transition zone of 50 degrees Celsius or less.

[0057] The heating element may utilize a nonlinear PTCR material to enable inherent temperature control. For example, a heating element at ambient temperature may be connected to a power source that provides a voltage gradient, resulting in the flow of current. Because the resistivity of the heating element is relatively low at ambient temperature (e.g., the ambient temperature is below the transition zone), current will flow through the heating element. As current flows through the nonlinear PTCR material, heat is generated due to resistance (e.g., power dissipation). The generated heat increases the temperature of the heating element, thereby changing the resistivity of the heating element. When the temperature of the heating element reaches the transition zone, the resistivity increases significantly over a small temperature range. The change in resistivity may be caused by the physical properties of the material. For example, a phase transition may occur within the material. This increase in resistivity (resulting in an increase in overall resistance) reduces the flow of current, thereby reducing heat generation. The transition zone includes the temperature at which an inflection point exists, limiting the temperature of the heating element by generating insufficient heat to further increase the temperature of the heating element. As long as the power supply remains connected and continues to provide current, the heating element will maintain a uniform temperature with minimal temperature fluctuations. In this case, the power supplied to the PTCR heating element is P I = Voltage 2 The heat loss of a PTCR heating element can be expressed as P L and includes any combination of conductive, convective, radiative, and latent heat. During steady-state operation, P I =P L P L As P increases, the temperature of the PTCR heating element decreases, which decreases the resistance and increases the flow of current through the PTCR heating element. L As P decreases, the temperature of the PTCR heating element increases, which increases the resistance and reduces the flow of current through the PTCR heating element. L The resistance of a PTCR heating element increases logarithmically as approaches 0. The operating temperature limit of a PTCR heating element may be affected by the element material, element geometry, element resistivity as a function of temperature characteristics, power supply, circuit characteristics (e.g., voltage gradient, current, time delay characteristics), etc.

[0058] FIG. 9 is a plot illustrating an exemplary resistivity versus temperature curve for a nonlinear PTCR material. The vertical axis is logarithmic. Heating elements constructed (e.g., formed) from nonlinear PTCR materials (referred to as PTCR heaters) may have advantageous properties. For example, when a sufficient voltage gradient (e.g., ∇V) is applied, the PTCR heater heats up and increases in temperature until it reaches a transition zone. In the curve illustrated in FIG. 9, the transition zone spans temperatures T1 and T2. In the curve illustrated in FIG. 9, the resistivity versus temperature curve appears nonlinear between T1 and T2, but in other embodiments, the resistivity versus temperature curve may be approximately linear, linear, or otherwise. At some temperature above T1, the resistivity of the nonlinear PTCR material will increase to a point where further temperature increase will cease because the overall resistance will increase to a predetermined point, thereby limiting current flow. In other words, embodiments of the PTCR heater may be considered temperature self-limiting, and will not heat beyond the low point T1 of the temperature transition zone given a known range of applied voltage.

[0059] The performance of a PTCR heater can depend on the PTCR behavior and heater geometry, as shown in FIG. 9 . PTCR heaters with relatively long and narrow geometries and electrical contacts at each end of their long dimension for applying different voltages can be ineffective in that the resistivity of the nonlinear PTCR material is typically too high at temperatures below T1. Nonlinear PTCR materials with abrupt transition zones where the temperature difference between T1 and T2 is less than 10°C can cause all voltage drops to occur within a small portion of the length of the long and narrow geometry, inevitably imparting spatial nonuniformity within any given material. Therefore, some implementations of PTCR heaters include electrode structures for the PTCR heater, which provide the nonlinear PTCR material in a parallel circuit. In some embodiments that can provide improved heating uniformity, the PTCR heater geometry can include a thin section of nonlinear PTCR material sandwiched between conductors or conductive coatings to which different voltages can be applied.

[0060] FIG. 10 presents a table of resistivity versus temperature curve data for the nonlinear PTCR semiconductor material shown in FIG. 9. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 100 Ω·cm at 100°C and a resistivity of 50,000 Ω·cm to 150,000 Ω·cm at 260°C. In some embodiments, the PTCR heating element has a resistivity of 20 Ω·cm to 200 Ω·cm at 100°C and a resistivity of 100,000 Ω·cm to 200,000 Ω·cm at 265°C. In some embodiments, the PTCR heating element has a resistivity less than 100 Ω·cm at 100°C and a resistivity greater than 100,000 Ω·cm at 260°C. In some embodiments, the PTCR heating element has a resistivity less than 100 Ω·cm at 100°C and a resistivity greater than 250,000 Ω·cm at 275°C. In some embodiments, the PTCR heating element has a resistivity of less than 100 Ω·cm at 100° C. and greater than 300,000 Ω·cm at 295° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 110 Ω·cm at 25° C., a resistivity of 10 Ω·cm to 110 Ω·cm at 100° C., and a resistivity of 100,000 Ω·cm to 325,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 150 Ω·cm at 25° C., a resistivity of 10 Ω·cm to 150 Ω·cm at 100° C., and a resistivity of 100,000 Ω·cm to 350,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 200 Ω·cm at 25° C., a resistivity of 10 Ω·cm to 200 Ω·cm at 100° C., and a resistivity of 100,000 Ω·cm to 375,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 300 Ω·cm at 25° C., a resistivity of 10 Ω·cm to 300 Ω·cm at 100° C., and a resistivity of 100,000 Ω·cm to 400,000 Ω·cm at 280° C.In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 400 Ω·cm at 25° C., a resistivity of 10 Ω·cm to 400 Ω·cm at 100° C., and a resistivity of 100,000 Ω·cm to 450,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 500 Ω·cm at 25° C., a resistivity of 10 Ω·cm to 500 Ω·cm at 100° C., and a resistivity of 100,000 Ω·cm to 500,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 110 Ω·cm at 25° C., a resistivity of 50 Ω·cm to 110 Ω·cm at 100° C., and a resistivity of 150,000 Ω·cm to 325,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 150 Ω·cm at 25° C., a resistivity of 50 Ω·cm to 150 Ω·cm at 100° C., and a resistivity of 150,000 Ω·cm to 350,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 200 Ω·cm at 25° C., a resistivity of 50 Ω·cm to 200 Ω·cm at 100° C., and a resistivity of 150,000 Ω·cm to 375,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 300 Ω·cm at 25° C., a resistivity of 50 Ω·cm to 300 Ω·cm at 100° C., and a resistivity of 150,000 Ω·cm to 400,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 400 Ω·cm at 25° C., a resistivity of 50 Ω·cm to 400 Ω·cm at 100° C., and a resistivity of 150,000 Ω·cm to 450,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 500 Ω·cm at 25° C., a resistivity of 50 Ω·cm to 500 Ω·cm at 100° C., and a resistivity of 150,000 Ω·cm to 500,000 Ω·cm at 280° C.In some embodiments, the PTCR heating element has a resistivity of 90 Ω·cm to 110 Ω·cm at 25° C., a resistivity of 90 Ω·cm to 110 Ω·cm at 100° C., and a resistivity of 200,000 Ω·cm to 325,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 90 Ω·cm to 150 Ω·cm at 25° C., a resistivity of 90 Ω·cm to 150 Ω·cm at 100° C., and a resistivity of 200,000 Ω·cm to 350,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 90 Ω·cm to 200 Ω·cm at 25° C., a resistivity of 90 Ω·cm to 200 Ω·cm at 100° C., and a resistivity of 200,000 Ω·cm to 375,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 90 Ω·cm to 300 Ω·cm at 25° C., a resistivity of 90 Ω·cm to 300 Ω·cm at 100° C., and a resistivity of 200,000 Ω·cm to 400,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 90 Ω·cm to 400 Ω·cm at 25° C., 90 Ω·cm to 400 Ω·cm at 100° C., and 200,000 Ω·cm to 450,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 90 Ω·cm to 500 Ω·cm at 25° C., 90 Ω·cm to 500 Ω·cm at 100° C., and 200,000 Ω·cm to 500,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 110 Ω·cm at 50° C., a resistivity of 10 Ω·cm to 50 Ω·cm at 150° C., and a resistivity of 50,000 Ω·cm to 125,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 150 Ω·cm at 50° C., a resistivity of 10 Ω·cm to 100 Ω·cm at 150° C., and a resistivity of 50,000 Ω·cm to 150,000 Ω·cm at 260° C.In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 200 Ω·cm at 50° C., a resistivity of 10 Ω·cm to 150 Ω·cm at 150° C., and a resistivity of 50,000 Ω·cm to 175,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 300 Ω·cm at 50° C., a resistivity of 10 Ω·cm to 200 Ω·cm at 150° C., and a resistivity of 50,000 Ω·cm to 200,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 400 Ω·cm at 50° C., a resistivity of 10 Ω·cm to 250 Ω·cm at 150° C., and a resistivity of 50,000 Ω·cm to 250,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 500 Ω·cm at 50° C., a resistivity of 10 Ω·cm to 300 Ω·cm at 150° C., and a resistivity of 50,000 Ω·cm to 300,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 110 Ω·cm at 50° C., a resistivity of 20 Ω·cm to 50 Ω·cm at 150° C., and a resistivity of 75,000 Ω·cm to 125,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 150 Ω·cm at 50° C., a resistivity of 20 Ω·cm to 100 Ω·cm at 150° C., and a resistivity of 75,000 Ω·cm to 150,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 200 Ω·cm at 50° C., a resistivity of 20 Ω·cm to 150 Ω·cm at 150° C., and a resistivity of 75,000 Ω·cm to 175,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 300 Ω·cm at 50° C., a resistivity of 20 Ω·cm to 200 Ω·cm at 150° C., and a resistivity of 75,000 Ω·cm to 200,000 Ω·cm at 260° C.In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 400 Ω·cm at 50° C., a resistivity of 20 Ω·cm to 250 Ω·cm at 150° C., and a resistivity of 75,000 Ω·cm to 250,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 500 Ω·cm at 50° C., a resistivity of 20 Ω·cm to 300 Ω·cm at 150° C., and a resistivity of 75,000 Ω·cm to 300,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 75 Ω·cm to 110 Ω·cm at 50° C., a resistivity of 30 Ω·cm to 50 Ω·cm at 150° C., and a resistivity of 100,000 Ω·cm to 125,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 75 Ω·cm to 150 Ω·cm at 50° C., a resistivity of 30 Ω·cm to 100 Ω·cm at 150° C., and a resistivity of 100,000 Ω·cm to 150,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 75 Ω·cm to 200 Ω·cm at 50° C., a resistivity of 30 Ω·cm to 150 Ω·cm at 150° C., and a resistivity of 100,000 Ω·cm to 175,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 75 Ω·cm to 300 Ω·cm at 50° C., a resistivity of 30 Ω·cm to 200 Ω·cm at 150° C., and a resistivity of 100,000 Ω·cm to 200,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 75 Ω·cm to 400 Ω·cm at 50°C, a resistivity of 30 Ω·cm to 250 Ω·cm at 150°C, and a resistivity of 100,000 Ω·cm to 250,000 Ω·cm at 260°C. In some embodiments, the PTCR heating element has a resistivity of 75 Ω·cm to 500 Ω·cm at 50° C., a resistivity of 30 Ω·cm to 300 Ω·cm at 150° C., and a resistivity of 100,000 Ω·cm to 300,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 110 Ω·cm at 25° C., a resistivity of 10 Ω·cm to 50 Ω·cm at 150° C., and a resistivity of 100,000 Ω·cm to 325,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 150 Ω·cm at 25° C., a resistivity of 10 Ω·cm to 100 Ω·cm at 150° C., and a resistivity of 100,000 Ω·cm to 350,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 200 Ω·cm at 25° C., a resistivity of 10 Ω·cm to 150 Ω·cm at 150° C., and a resistivity of 100,000 Ω·cm to 375,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 300 Ω·cm at 25° C., a resistivity of 10 Ω·cm to 200 Ω·cm at 150° C., and a resistivity of 100,000 Ω·cm to 400,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 400 Ω·cm at 25° C., a resistivity of 10 Ω·cm to 250 Ω·cm at 150° C., and a resistivity of 100,000 Ω·cm to 450,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 500 Ω·cm at 25° C., a resistivity of 10 Ω·cm to 300 Ω·cm at 150° C., and a resistivity of 100,000 Ω·cm to 500,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 110 Ω·cm at 25° C., a resistivity of 20 Ω·cm to 50 Ω·cm at 150° C., and a resistivity of 150,000 Ω·cm to 325,000 Ω·cm at 280° C.In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 150 Ω·cm at 25° C., a resistivity of 20 Ω·cm to 100 Ω·cm at 150° C., and a resistivity of 150,000 Ω·cm to 350,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 200 Ω·cm at 25° C., a resistivity of 20 Ω·cm to 150 Ω·cm at 150° C., and a resistivity of 150,000 Ω·cm to 375,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 300 Ω·cm at 25° C., a resistivity of 20 Ω·cm to 200 Ω·cm at 150° C., and a resistivity of 150,000 Ω·cm to 400,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 400 Ω·cm at 25° C., a resistivity of 20 Ω·cm to 250 Ω·cm at 150° C., and a resistivity of 150,000 Ω·cm to 450,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 500 Ω·cm at 25° C., a resistivity of 20 Ω·cm to 300 Ω·cm at 150° C., and a resistivity of 150,000 Ω·cm to 500,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 90 Ω·cm to 110 Ω·cm at 25° C., a resistivity of 30 Ω·cm to 50 Ω·cm at 150° C., and a resistivity of 200,000 Ω·cm to 325,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 90 Ω·cm to 150 Ω·cm at 25° C., a resistivity of 30 Ω·cm to 100 Ω·cm at 150° C., and a resistivity of 200,000 Ω·cm to 350,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 90 Ω·cm to 200 Ω·cm at 25° C., a resistivity of 30 Ω·cm to 150 Ω·cm at 150° C., and a resistivity of 200,000 Ω·cm to 375,000 Ω·cm at 280° C.In some embodiments, the PTCR heating element has a resistivity of 90 Ω·cm to 300 Ω·cm at 25° C., a resistivity of 30 Ω·cm to 200 Ω·cm at 150° C., and a resistivity of 200,000 Ω·cm to 400,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 90 Ω·cm to 400 Ω·cm at 25° C., a resistivity of 30 Ω·cm to 250 Ω·cm at 150° C., and a resistivity of 200,000 Ω·cm to 450,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 90 Ω·cm to 500 Ω·cm at 25° C., 30 Ω·cm to 300 Ω·cm at 150° C., and 200,000 Ω·cm to 500,000 Ω·cm at 280° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 110 Ω·cm at 50° C., 10 Ω·cm to 110 Ω·cm at 100° C., and 50,000 Ω·cm to 125,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 150 Ω·cm at 50° C., a resistivity of 10 Ω·cm to 150 Ω·cm at 100° C., and a resistivity of 50,000 Ω·cm to 150,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 200 Ω·cm at 50° C., a resistivity of 10 Ω·cm to 200 Ω·cm at 100° C., and a resistivity of 50,000 Ω·cm to 175,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 300 Ω·cm at 50° C., a resistivity of 10 Ω·cm to 300 Ω·cm at 100° C., and a resistivity of 50,000 Ω·cm to 200,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 400 Ω·cm at 50° C., a resistivity of 10 Ω·cm to 400 Ω·cm at 100° C., and a resistivity of 50,000 Ω·cm to 250,000 Ω·cm at 260° C.In some embodiments, the PTCR heating element has a resistivity of 10 Ω·cm to 500 Ω·cm at 50° C., a resistivity of 10 Ω·cm to 500 Ω·cm at 100° C., and a resistivity of 50,000 Ω·cm to 300,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 110 Ω·cm at 50° C., a resistivity of 50 Ω·cm to 110 Ω·cm at 100° C., and a resistivity of 75,000 Ω·cm to 125,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 150 Ω·cm at 50° C., a resistivity of 50 Ω·cm to 150 Ω·cm at 100° C., and a resistivity of 75,000 Ω·cm to 150,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 200 Ω·cm at 50° C., a resistivity of 50 Ω·cm to 200 Ω·cm at 100° C., and a resistivity of 75,000 Ω·cm to 175,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 300 Ω·cm at 50° C., a resistivity of 50 Ω·cm to 300 Ω·cm at 100° C., and a resistivity of 75,000 Ω·cm to 200,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 400 Ω·cm at 50° C., a resistivity of 50 Ω·cm to 400 Ω·cm at 100° C., and a resistivity of 75,000 Ω·cm to 250,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 50 Ω·cm to 500 Ω·cm at 50° C., a resistivity of 50 Ω·cm to 500 Ω·cm at 100° C., and a resistivity of 75,000 Ω·cm to 300,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 75 Ω·cm to 110 Ω·cm at 50° C., a resistivity of 90 Ω·cm to 110 Ω·cm at 100° C., and a resistivity of 100,000 Ω·cm to 125,000 Ω·cm at 260° C.In some embodiments, the PTCR heating element has a resistivity of 75 Ω·cm to 150 Ω·cm at 50° C., 90 Ω·cm to 150 Ω·cm at 100° C., and 100,000 Ω·cm to 150,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 75 Ω·cm to 200 Ω·cm at 50° C., 90 Ω·cm to 200 Ω·cm at 100° C., and 100,000 Ω·cm to 175,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 75 Ω·cm to 300 Ω·cm at 50° C., 90 Ω·cm to 300 Ω·cm at 100° C., and 100,000 Ω·cm to 200,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 75 Ω·cm to 400 Ω·cm at 50° C., 90 Ω·cm to 400 Ω·cm at 100° C., and 100,000 Ω·cm to 250,000 Ω·cm at 260° C. In some embodiments, the PTCR heating element has a resistivity of 75 Ω·cm to 500 Ω·cm at 50°C, a resistivity of 90 Ω·cm to 500 Ω·cm at 100°C, and a resistivity of 100,000 Ω·cm to 300,000 Ω·cm at 260°C.

[0061] FIG. 11 shows another exemplary PTCR resistivity versus temperature curve. In this example, the PTCR material has a density of 5700 kg / m³, a heat capacity of 520 J / kg K, and a thermal conductivity of 2.1 W / m K. The coefficient of resistivity initially begins to increase above about 440 K, then increases sharply between 503 K and 518 K. At 298 K, the resistivity of the PTCR material forming the PTCR heating element is 0.168 Ω·m; at 373 K, the resistivity of the PTCR material forming the PTCR heating element is 0.105 Ω·m; and at 518 K, the resistivity of the PTCR material forming the PTCR heating element is 3.669 Ω·m. In some exemplary embodiments, the PTCR material has a density of 5000 kg / m³ to 7000 kg / m³, a heat capacity of 450 J / kg K to 600 J / kg K, and a thermal conductivity of 1.5 W / m K to 3.0 W / m K.

[0062] Figure 12A illustrates an exemplary PTCR heating element 50 that can provide improved vaporizer heating. A thin section of nonlinear PTCR material 10 is shown in Figure 12A, where the nonlinear PTCR material 10 is sandwiched between conductive layers 20, which are also attached to each of the conductive leads 30 so that each of the conductive leads 30 can have a different applied voltage. Figure 12B illustrates a cross-sectional view of the exemplary PTCR heating element 50 shown in Figure 12A.

[0063] In some exemplary embodiments that may be useful in vaporizer devices using fluid combinations including, for example, propylene glycol and glycerol, the PTCR heater 50 has the geometry shown in FIG. 12A with a nonlinear PTCR material thickness of 0.5 mm (height) and 5.0 mm (length and width), but with other dimensions. The electrical properties of the nonlinear PTCR material have the following values: a T1 value between 150°C and 300°C, e.g., between 220°C and 280°C; a resistivity at temperatures below T1 between 0.01 Ω·m and 100 Ω·m, e.g., between 0.1 Ω·m and 1 Ω·m; a resistivity change from T1 to T2 that increases by more than 10 times, e.g., more than 100 times; and a temperature difference between T1 and T2 that is less than 200°C, e.g., less than 50°C.

[0064] 13A-13E show a temperature model of an exemplary PTCR heater 50. In the illustrated example, the nonlinear PTCR material 10 had a plate geometry with dimensions of 5 mm x 5 mm x 0.5 mm. The conductive layer 20 was formed of silver (Ag) with dimensions of 5 mm x 5 mm x 0.025 mm. The conductive leads 30 were formed of copper (Cu) with dimensions of 12 mm x 2 mm x 0.2 mm. The nonlinear PTCR material 10 had a PTCR resistivity versus temperature curve with a nonlinear transition zone from about 240°C to about 300°C, as shown in FIG. 32. A voltage of 3 to 6 volts was applied across the conductive leads 30 of the exemplary PTCR heater 50. Under these circumstances, an exemplary PTCR heater 50 in open air with free convection airflow will increase in temperature as shown in the sequence model of Figures 13A-13E, which represent 0.0, 0.2, 0.5, 1.0, and 2.0 seconds, respectively, after application of the voltage difference. As shown, the temperature past 1.0 second is relatively uniform, with a peak temperature at the surface of the conductive layer 20 below 270°C.

[0065] 14A-14F show temperature models of another exemplary PTCR heater 50. A gradient temperature scale is shown on the left side of each figure, with red representing a maximum temperature of approximately 255°C and continuing through the colors of the visible light spectrum (i.e., red, orange, yellow, green, blue, and purple) to a minimum temperature of approximately 23°C. In each example shown, the nonlinear PTCR material 10 has a plate geometry measuring approximately 5 mm x 5 mm x 0.5 mm. The conductive layer 20 was formed from silver (Ag) with dimensions of approximately 5 mm x 5 mm x 0.025 mm, and the conductive leads 30 were formed from copper (Cu) with dimensions of approximately 12 mm x 2 mm x 0.2 mm. The plate geometry may have two parallel faces including the conductive layer 20 with the conductive leads 30 attached. The conductive leads 30 are attached to the center of the conductive layer 20 on either side of the PTCR heating element 50 by connection means 40. In embodiments, the connection means 40 is a clamp, a clip, a conductive paste, a high temperature, lead-free solder, and / or a combination thereof.

[0066] 14A shows the temperature 1.0 second after activation by passing a current through the PTCR heating element 50. The purple colored conductive lead 30 is still at about 25° C. The majority of the PTCR material 10 and conductive layer 20 has risen in temperature to about 120° C., while the area containing the central connection means 40 is slightly cooler at a temperature of about 80° C.

[0067] 14B shows the temperature 2.0 seconds after activation by passing a current through the PTCR heating element 50. The blue / green colored conductive leads 30 have increased in temperature to approximately 90° C. The majority of the PTCR material 10 and conductive layer 20 have increased in temperature to approximately 210° C., with the area containing the central connection means 40 remaining relatively cooler at a temperature of approximately 160° C.

[0068] 14C shows the temperature 3.0 seconds after activation by passing a current through the PTCR heating element 50. The green colored conductive lead 30 has increased in temperature to approximately 140° C. The majority of the PTCR material 10 and conductive layer 20 has increased in temperature to approximately 250° C., with the area containing the central connection means 40 remaining relatively cooler at a temperature of approximately 200° C.

[0069] 14D shows the temperature 4.0 seconds after activation by passing a current through the PTCR heating element 50. The green colored conductive lead 30 has increased in temperature to approximately 160° C. The majority of the PTCR material 10 and conductive layer 20 remains at a temperature of approximately 250° C., while the area containing the central connection means 40 is relatively cooler at a temperature of approximately 215° C.

[0070] 14E shows the temperature 5.0 seconds after activation by passing current through the PTCR heater 50. The green / yellow colored conductive leads 30 have increased in temperature to approximately 180° C. The majority of the PTCR material 10 and conductive layer 20 remain at a temperature of approximately 250° C., with the area containing the central connection means 40 being slightly cooler at a temperature of approximately 225° C.

[0071] Figure 14F shows the temperature 6.0 seconds after activation by passing current through the PTCR heating element 50. The yellow colored conductive leads 30 have increased in temperature to approximately 200°C. The majority of the PTCR material 10 and conductive layer 20 remain at a temperature of approximately 250°C, with the area containing the central connecting means 40 being only slightly cooler at a temperature of approximately 235°C. Figure 15 shows the temperature model of an exemplary heater 6.0 seconds after voltage application under free convection conditions.

[0072] FIG. 16A shows a surface temperature model as a function of time for an exemplary PTCR heating element. In this model, the surface temperature of the PTCR heater begins at time zero at 25°C (i.e., room temperature). After current is applied, the surface temperature increases linearly for approximately 2 seconds to a temperature of approximately 225°C. After approximately 2 seconds, the rate of temperature increase slows, and a steady-state operating temperature of approximately 250°C is achieved approximately 3 seconds after activation. In this model, the nonlinear PTCR material is assumed to be in a non-contact, free-convection state, and the emitted radiation is measured from a predetermined distance. In some embodiments, the PTCR heating element is heated to an operating temperature of 240°C to 280°C. In some embodiments, the PTCR heating element is heated to an operating temperature of 245°C to 255°C. In some embodiments, the PTCR heating element is heated to an operating temperature of approximately 250°C.

[0073] FIG. 16B shows a model of the measured maximum surface temperature as a function of time for an exemplary PTCR heater. To measure the maximum surface temperature of the PTCR heater as a function of time, four measurements were taken using an infrared camera and then plotted against the maximum surface temperature model. This model assumed that the nonlinear PTCR material was in a noncontact, free-convection state and that the emitted radiation was measured from a predetermined distance. In each case, the maximum surface temperature of the PTCR heating element begins at time zero at approximately 25°C (i.e., room temperature). After current is applied, the maximum surface temperature increases linearly for approximately 2 seconds to a temperature of approximately 225°C. After approximately 2 seconds, the rate of temperature increase slows, and a steady-state operating temperature of approximately 250°C is achieved approximately 3 seconds after activation. In some embodiments, the PTCR heating element is heated to an operating temperature of 240°C to 280°C. In some embodiments, the PTCR heating element is heated to an operating temperature of 245°C to 255°C. In some embodiments, the PTCR heating element is heated to an operating temperature of about 250°C.

[0074] FIG. 16C shows a model of the measured average surface temperature as a function of time for an exemplary PTCR heating element. To measure the average surface temperature of a PTCR heating element as a function of time, four measurements were taken using an infrared camera and then plotted against the average surface temperature model. This model assumed that the nonlinear PTCR material was in a noncontact, free-convection state and that emitted radiation was measured from a predetermined distance. In each case, the average surface temperature of the PTCR heating element begins at time zero at approximately 25°C (i.e., room temperature). After current is applied, the maximum surface temperature increases linearly for approximately 2 seconds, reaching a temperature of approximately 225°C. After approximately 2 seconds, the rate of temperature increase slows, and a steady-state operating temperature of approximately 250°C is achieved approximately 3 seconds after activation. In some embodiments, the PTCR heating element is heated to an operating temperature of 240°C to 280°C. In some embodiments, the PTCR heating element is heated to an operating temperature of 245°C to 255°C. In some embodiments, the PTCR heating element is heated to an operating temperature of about 250°C.

[0075] 17 shows the transient current response of an exemplary heater as a function of time, consistent with embodiments of the present subject matter. In this graph, the current, measured in amperes, increases at a nearly linear rate, reaching a peak current approximately 1.5 seconds after activation. Thereafter, as the PTCR heater reaches its self-regulating operating temperature, its resistance increases rapidly, reducing the current flow.

[0076] Uniform temperature may be a desirable performance attribute of PTCR heaters, offering distinct advantages over series coil heaters, including series heaters with power input controlled by temperature sensors, microprocessor-based electronics, and specialized advanced algorithms for temperature control. These existing series heaters can adjust overall power in response to temperature measurements at a point or an average temperature estimated by the overall electrical resistivity combined with the TCR (temperature coefficient of resistivity) of a typical series heating element. However, in some series heaters, the temperature within the series heater can vary by 40°C or more because of localized resistivity variations along the series heater caused by localized differences in the thermal mass of the surrounding medium and localized differences in losses to the surrounding medium.

[0077] In some embodiments, the PTCR heater 50 is constructed of a material having a nonlinear PTCR resistivity versus temperature curve the same as or similar to that shown in FIG. 9, has a parallel geometry as shown in FIGS. 12A-12B, and has an appropriate differential voltage (e.g., 3V-6V) applied to the conductive leads 30. Each controlled volume provided within such a PTCR heater has a temperature within a narrow range, typically less than 10°C. This can be achieved even with different heat loads. The less than 10°C range can be tailored for vaporization by controlling the material and geometry of the PTCR heating element.

[0078] Alternative PTCR heater designs and geometries are possible.

[0079] In some embodiments, the PTCR heater may include a heat exchanger to preheat the air flowing through and passing over the vaporizable material. Figure 18 is a perspective view of an exemplary PTCR heater assembly 395 including a PTCR heater 390 and a heat exchanger member 320 that may enable convective heating and improved uniform heating of the vaporizable material.

[0080] The exemplary PTCR heater assembly 395 (also referred to as a rectangular PTCR air heater assembly) includes a PTCR heater 390 having PTCR material 300 sandwiched between conductive layers 305. The heat exchanger member 320 in contact with the conductive layers 305 may be made of, for example, aluminum or another thermally conductive material. The heat exchanger member 320 may be made of a thermally conductive material extrusion or assembly. In embodiments, the heat exchanger member 320 may be a metal foam, such as aluminum foam. The heat exchanger member 320 may be manufactured by extrusion, machining, milling, casting, foaming, printing, injection molding, forging, stamping, sintering, and other metal forming methods. Surrounding the heat exchanger member 320 is a heater assembly cover 350. In embodiments, the heater assembly cover 350 comprises a non-conductive material. In embodiments, the heater assembly cover 350 comprises a non-thermally conductive material. In some embodiments, heater assembly cover 350 comprises a metal with a non-conductive coating that insulates heater assembly cover 350 from heat exchanger member 320. In some embodiments, heater assembly cover 350 comprises polytetrafluoroethylene (PTFE).

[0081] FIG. 19 is an exploded view of a PTCR vaporization assembly 398, including an exploded view of an exemplary PTCR heater assembly 395. In some embodiments, the PTCR vaporization assembly 398 is rectangular. The PTCR vaporization assembly 398 includes the exemplary PTCR heater assembly 395 and a product cover 380 for housing a disposable product 360. In some embodiments, the product cover 380 and the disposable product 360 are each rectangular. In some embodiments, the disposable product 360 within the product cover 380 may include a disposable product containing a solid vaporizable material. In some embodiments, the product cover 380 is a disposable liquid cartridge (e.g., a pod) configured to house a liquid vaporizable material. In some embodiments, the product cover 380 is a disposable liquid cartridge (e.g., a pod) having a first air inlet and / or a wick and configured to house a liquid vaporizable material.

[0082] 20 is a perspective view of an exemplary assembled PTCR vaporizer assembly 398. A product cover 380, which houses a disposable product therein, may be attached to the heater assembly cover 350, the PTCR heater assembly, and / or adjacent segments opposite the product cover 380 via an interference fit, press fit, snap fit connection, magnetic connection, adhesive, and other fastening means. The product cover 380 may be removably attached, allowing the product cover 380 to be separated from the vaporizer device, the disposable product replaced, and then reassembled.

[0083] FIG. 21 is a perspective view of an exemplary PTCR vaporization assembly 398 and disposable product 360. In some embodiments, the disposable product 360 and product cover 380 may comprise a disposable product containing a solid vaporizable material. In some embodiments, the disposable product 360 and product cover 380 may comprise a disposable liquid cartridge (e.g., a pod) containing a liquid vaporizable material. In some embodiments, the disposable product 360 and product cover 380 may comprise a disposable liquid cartridge (e.g., a pod) having a first air inlet and / or wick to contain the liquid vaporizable material. While the PTCR heater is not shown in FIG. 21 , the PTCR heater is inserted into the volume 304 between the heat exchanger members 320. The heat exchanger members 320 provide an increased surface area for heating more incoming air than would be possible with a PTCR heater alone (without a heat exchanger). Surrounding the heat exchanger members 320 is a heater assembly cover 350. In some embodiments, the flow rate of the incoming air through the PTCR heater assembly 395 is approximately 1.4 liters per minute. The heat exchanger member 320 can reach a steady state temperature of over 200° C. to rapidly heat the incoming air. The heat exchanger member 320 has a specific surface area (mm 2 / mm 3 ), which results in improved heat transfer from the PTCR heater to the heat exchanger element 320, as well as improved heat transfer from the heat exchanger element 320 to the incoming air. As shown in FIG. 21, the heat exchanger element 320 may be a finned design made of a thermally conductive material (e.g., a metal such as aluminum, copper, steel, stainless steel, titanium, etc.).

[0084] 22 is a perspective, see-through view of an exemplary PTCR vaporization assembly 398 and disposable product 360 approximately 0.2 seconds after activation of the PTCR heater 390. The PTCR heater 390 heats the heat exchanger member 320, which transfers heat to air entering the PTCR heater assembly 395. The air exiting the PTCR heater assembly 395 is heated to a temperature of approximately 110°C to approximately 160°C. The heated airflow flows through the disposable product 360 (e.g., tobacco-containing medium) at a flow rate of approximately 1.4 liters per minute. The vapor and / or aerosol exiting the PTCR vaporization assembly 398 contains vaporized material emitted from the disposable product 360 at a temperature of approximately 50°C to approximately 150°C.

[0085] 23 is a perspective, see-through view of an exemplary PTCR vaporization assembly 398 and disposable product 360 approximately 0.5 seconds after activation of the PTCR heater 390. The PTCR heater 390 heats the heat exchanger member 320, which transfers heat to air entering the PTCR heater assembly 395. The air exiting the PTCR heater assembly 395 is heated to a temperature of approximately 150°C to approximately 210°C. The heated airflow flows through the disposable product 360 (e.g., tobacco-containing medium) at a flow rate of approximately 1.4 liters per minute. The vapor and / or aerosol exiting the PTCR vaporization assembly 398 contains vaporized material emitted from the disposable product 360 at a temperature of approximately 100°C to approximately 210°C.

[0086] 24 is a perspective, see-through view of an exemplary PTCR vaporization assembly 398 and disposable product 360 approximately 1.0 seconds after activation of the PTCR heater 390. The PTCR heater 390 heats the heat exchanger member 320, which transfers heat to air entering the PTCR heater assembly 395. The air exiting the PTCR heater assembly 395 is heated to a temperature of approximately 170°C to approximately 230°C. The heated airflow flows through the disposable product 360 (e.g., tobacco-containing medium) at a flow rate of approximately 1.4 liters per minute. The vapor and / or aerosol exiting the PTCR vaporization assembly 398 contains vaporized material emitted from the disposable product 360 at a temperature of approximately 110°C to approximately 220°C.

[0087] 25 is a perspective, see-through view of an exemplary PTCR vaporization assembly 398 and disposable product 360 approximately 2.0 seconds after activation of the PTCR heater 390. The PTCR heater 390 heats the heat exchanger member 320, which transfers heat to air entering the PTCR heater assembly 395. The air exiting the PTCR heater assembly 395 is heated to a temperature of approximately 180°C to approximately 240°C. The heated airflow flows through the disposable product 360 (e.g., tobacco-containing medium) at a flow rate of approximately 1.4 liters per minute. The vapor and / or aerosol exiting the PTCR vaporization assembly 398 contains vaporized material emitted from the disposable product 360 at a temperature of approximately 120°C to approximately 230°C.

[0088] 26 is a perspective, see-through view of an exemplary PTCR vaporization assembly 398 and disposable product 360 approximately 3.0 seconds after activation of the PTCR heater 390. The PTCR heater 390 heats the heat exchanger member 320, which transfers heat to air entering the PTCR heater assembly 395. The air exiting the PTCR heater assembly 395 is heated to a temperature of approximately 180°C to approximately 240°C. The heated airflow flows through the disposable product 360 (e.g., tobacco-containing medium) at a flow rate of approximately 1.4 liters per minute. The vapor and / or aerosol exiting the PTCR vaporization assembly 398 contains vaporized material emitted from the disposable product 360 at a temperature of approximately 120°C to approximately 230°C.

[0089] The present subject matter is not limited to rectangular geometries. In some embodiments, the PTCR heater is a polygonal shape that is not rectangular. For example, alternative designs of PTCR heaters may differ from planar geometries in many possible configurations manufactured by extrusion or injection molding. For example, FIG. 27 is a perspective view of an exemplary PTCR heater 290 having a cylindrical geometry. In this example, the PTCR heaters 290 each include a PTCR material 200 with a cylindrical surface conductive layer 205.

[0090] Figure 28 is an exploded view of an exemplary PTCR heater assembly 295, which includes an exemplary PTCR heater 290, outer heat exchanger 210, inner heat exchanger 220, flow diverter 230, and heater assembly cover 250, each of which is cylindrical. Figure 29 is a perspective view of the exemplary PTCR heater assembly 295. Figure 30 is a perspective view of an exemplary PTCR vaporization assembly 298 with the outer cover and flow diverter 230 removed, thereby showing the orientation of the PTCR heater 290, outer heat exchanger 210, and inner heat exchanger 220 aligned with the disposable product 260.

[0091] FIG. 31 is a perspective view of an exemplary PTCR vaporization assembly 298 including a PTCR heater 290, an outer heat exchanger 210, an inner heat exchanger 220, a flow diverter 230, a heater assembly cover 250, and a product cover 280 (covering the disposable product 260 in FIG. 18).

[0092] 32 is a plot of the logarithm of resistivity as a function of temperature for an exemplary vaporization device with a PTCR heater. The performance shown in FIG. 32 is from an exemplary calculation characterizing the performance of an exemplary embodiment of a cylindrical PTCR vaporization assembly 298. The exemplary PTCR vaporization assembly 298 is an HNB device, and the calculations show that the specific surface area by mass is S m ≒10,000 cm 2 / g, and the density is ρ ≒ 300 kg / m 3 The disposable product 260 has a solid vaporizable material (e.g., HNB product) that is treated as a porous medium. The convective heat transfer coefficient is h≈2.0 W / m 2 K. The surface area by volume is S vol =S m xρ=10000cm 2 / g×1000g / kg×m 2 / 10000cm 2 can be calculated as S vol ≒1000m 2 / kg, the volumetric heat exchange coefficient is v = hρ(S vol ) ≒ 6.0E5W / m 3 It's K.

[0093] For this calculation, ambient conditions were 20.05°C at a standard pressure of 1 atmosphere. The input air flow rate was constant at 1.4 l / m and the applied voltage was a constant 3.7 volts across the opposing conductive layers 205. No current limiting was applied beyond the PTCR behavior shown in Figure 32.

[0094] The calculated vaporization device with a PTCR heater included a conductive layer 205 of silver, a cylindrical outer heat exchanger 210 and a cylindrical inner heat exchanger 220 that were aluminum extrusions, a flow divider 230 and heater assembly cover 250 made of PTFE, and a product cover 280 made of paper.

[0095] FIG. 33 is a cross-sectional plot illustrating a temperature simulation of an exemplary embodiment of a PTCR vaporization assembly 298, also described above with respect to FIG. 32. The PTCR vaporization assembly 298 includes a PTCR heater assembly 295 for heating a disposable product (e.g., a solid vaporizable material) 260. FIGS. 34A-34G are cut-away color plots illustrating the temperature transient response for an exemplary embodiment of the PTCR vaporization assembly 298 with the PTCR heater assembly 295. FIGS. 34A-34G demonstrate that the temperature never exceeds 280° C. anywhere, remaining well below the combustion temperature of the disposable product 260. In FIGS. 34A-34G, the heating of the disposable product (e.g., a solid vaporizable material) 260 progresses in a wave-like manner from upstream to downstream, eliminating cross-sectional hot spots and the resulting differential porosity of the pores.

[0096] FIG. 35 shows perspective and end views of a mouthpiece 335 having a vapor inlet 341, an aerosol outlet 342, and multiple air inlets. The multiple air inlets include a first plurality of air inlets 340b and a second plurality of air inlets 340c. The first plurality of air inlets 340a includes 14 holes (each hole providing an air inlet), and the second plurality of air inlets 340b includes another 14 holes (each hole providing an air inlet). In some embodiments, the first plurality of air inlets 340a includes 4 to 24 holes, and the second plurality of air inlets 340b includes 4 to 24 holes. Each of the holes in the multiple air inlets may be circular and have a diameter of approximately 0.4 mm. In some embodiments, each of the holes in the multiple air inlets may be circular and have a diameter of approximately 0.2 mm to approximately 0.6 mm. Each of the holes in the multiple air inlets may be arranged in a single plane. Each hole may be formed through the thickness of mouthpiece 335 at an angle α of approximately 30 degrees from the outer surface of mouthpiece 335. In some embodiments, each hole may be formed through the thickness of mouthpiece 335 at an angle α of approximately 15 to 45 degrees from the outer surface of mouthpiece 335. The angle α of each hole in first plurality of air inlets 340a may have an interior angle α that opens in the same direction relative to the interior angle of an adjacent hole. The angle α of each hole in second plurality of air inlets 340b may have an interior angle α that opens in the same direction relative to the interior angle of an adjacent hole. Mouthpiece 335 may taper from vapor inlet 341 to aerosol outlet 342. The cross-sectional area of ​​vapor inlet 341 may be at least four times larger than the cross-sectional area of ​​aerosol outlet 342. In some embodiments, the cross-sectional area of ​​vapor inlet 341 may be approximately 1.5 to 6 times larger than the cross-sectional area of ​​aerosol outlet 342.

[0097] FIG. 36 is a perspective, see-through view of a mouthpiece 335 attached to a PTCR rectangular vaporizer assembly 395. The vapor inlet of the mouthpiece 335 can be attached to the PTCR rectangular vaporizer assembly 395 via an interference fit, press fit, snap fit, magnetic coupling, adhesive, and other fastening means. The mouthpiece 335 can be removably attached to the product cover 380, allowing the two parts to be separated to replace the vaporizable product before reconnecting to each other. In another embodiment, the product cover 380 can be removed from the vaporizer assembly 390 to replace the vaporizable product contained therein, and then reconnected to each other. In this embodiment, the first plurality of air inlets 340a can include eight holes, and the second plurality of air inlets 340b can include another eight holes. The tapered body of the mouthpiece 335 provides a comfortable, adjustable fit for a user inhaling the aerosol exiting through the aerosol outlet 342.

[0098] FIG. 37 is a perspective, see-through view of a mouthpiece 335 attached to a PTCR rectangular vaporizer assembly 395, showing airflow and temperature patterns without benefit from the air entering the first and second air inlets 340a and 340b. The airflow is substantially laminar, poorly mixed through the PTCR rectangular vaporizer assembly 395, and adheres to the mouthpiece 335. The incoming air passing through the heat exchanger element 320 is rapidly heated to over 200°C before passing through the disposable rectangular product. As shown in FIG. 37, the aerosol exits the aerosol outlet 342 of the mouthpiece 335 and has cooled to an average temperature of 100°C to 160°C. The difference between the vapor inlet temperature and the aerosol outlet temperature is less than 100°C.

[0099] FIG. 38 is a perspective end view of a mouthpiece 335 having multiple air inlets, viewed through the aerosol outlet, illustrating the airflow pattern. The multiple air inlets include a first plurality of air inlets 340a and a second plurality of air inlets 340b. As shown in FIG. 38, the first plurality of air inlets 340a includes eight holes (each hole providing an air inlet), and the second plurality of air inlets 340b includes another eight holes (each hole providing an air inlet). As described above with respect to FIG. 35, each hole may be formed through the thickness of the mouthpiece 335 at an angle α of approximately 15 to 45 degrees from the outer surface of the mouthpiece 335. The angle α of each hole in the first plurality of air inlets 340a may have an interior angle that opens in the same direction relative to the interior angle of each adjacent hole. The angle α of each hole in the second plurality of air inlets 340b may have an interior angle that opens in the same direction relative to the interior angle of each adjacent hole. The holes of the multiple air inlets are each arranged in a single plane. The plane formed by the holes of the first plurality of air inlets 340a and the second plurality of air inlets 340b passes through the cross-section of the mouthpiece 335, which is shaped like two overlapping circles. Due to the circular arrangement of the holes and the relatively same interior angle α, air passing through the holes flows in a circular motion and forms a vortex. The first plurality of air streams moving through the first plurality of air inlets 340a form a first vortex, and the second plurality of air streams moving through the second plurality of air inlets 340b form a second vortex. The first vortex has a first axis of rotation and a first direction of rotation about the first axis of rotation. The first direction of rotation is determined by the interior angle α of each hole of the first plurality of air inlets 340a. The second vortex has a second axis of rotation and a second direction of rotation about the second axis of rotation. The second direction of rotation is determined by the interior angle α of each hole of the second plurality of air inlets 340b. The first and second rotation directions may be opposite directions. For example, the first rotation direction may be counterclockwise and the second rotation direction may be clockwise. In another implementation, the first rotation direction may be clockwise and the second rotation direction may be counterclockwise. In another realization, the first rotation direction may be clockwise and the second rotation direction may also be clockwise, or the first rotation direction may be counterclockwise and the second rotation direction may also be counterclockwise.The first and second axes of rotation are non-parallel due to the tapered mouthpiece 335. The first and second axes of rotation intersect at a point outside the vaporizer device, past the aerosol outlet.

[0100] The vortex generated within the mouthpiece 335 helps mix the air entering through the multiple air inlets to cool the aerosol exiting through the aerosol outlet. By generating counter-rotating vortices (i.e., one vortex rotating counterclockwise and one vortex rotating clockwise, or vice versa), the first multiple air flows collide with the second multiple air flows, creating turbulence, which further improves mixing of the vapor / aerosol and the incoming air inside the mouthpiece. Based on conservation of angular momentum, a mouthpiece 335 tapering from the vapor inlet to the aerosol outlet causes the vortex to rotate faster, creating additional turbulence and improved mixing. The turbulent mixing within the mouthpiece 335 creates a more uniform temperature profile for the aerosol exiting through the aerosol outlet without creating excessive pressure drop. This provides the user with an improved experience of inhaling aerosol at a comfortable temperature without excessive puffing. The turbulent mixing within the mouthpiece 335 results in smaller aerosol particles suitable for delivering the aerosol to the user's deep lung tissue, thereby avoiding deposition of the aerosol in the user's mouth or throat.

[0101] While this design is described with respect to a mouthpiece having an air inlet configured to generate two vortices, it is contemplated that more than two vortices may be generated within the mouthpiece. While a single vortex may provide some mixing of the incoming air and aerosol within the mouthpiece, some of the heated aerosol may flow along the axis of the single vortex and exit the aerosol outlet without being sufficiently cooled.

[0102] Figure 39 is a perspective, see-through view of mouthpiece 335 attached to PTCR rectangular vaporizer assembly 395, showing the airflow and temperature patterns 0.1 seconds after activation of the PTCR heater. Air exiting PTCR rectangular vaporizer assembly 395 is heated to a temperature of approximately 70°C to approximately 90°C. Air entering first and second air inlets 340a and 340b is at room temperature (approximately 20°C to approximately 25°C) and mixes with vapor entering the vapor inlet of mouthpiece 335. Aerosol exiting aerosol outlet 342 of mouthpiece 335 is cooled to a temperature of approximately 20°C to approximately 50°C.

[0103] Figure 40 is a perspective, see-through view of mouthpiece 335 attached to PTCR rectangular vaporizer assembly 395, showing the airflow and temperature patterns 0.2 seconds after activation of the PTCR heater. Air exiting PTCR rectangular vaporizer assembly 395 is heated to a temperature of approximately 110°C to approximately 160°C. Air entering first and second air inlets 340a and 340b is at room temperature (approximately 20°C to approximately 25°C) and mixes with vapor entering the vapor inlet of mouthpiece 335. Aerosol exiting aerosol outlet 342 of mouthpiece 335 is cooled to a temperature of approximately 25°C to approximately 60°C.

[0104] Figure 41 is a perspective, see-through view of mouthpiece 335 attached to PTCR rectangular vaporizer assembly 395, showing the airflow and temperature patterns 0.3 seconds after activation of the PTCR heater. Air exiting PTCR rectangular vaporizer assembly 395 is heated to a temperature of approximately 140°C to approximately 180°C. Air entering first and second air inlets 340a and 340b is at room temperature (approximately 20°C to approximately 25°C) and mixes with vapor entering the vapor inlet of mouthpiece 335. Aerosol exiting aerosol outlet 342 of mouthpiece 335 is cooled to a temperature of approximately 40°C to approximately 80°C.

[0105] 42 is a perspective, see-through view of mouthpiece 335 attached to PTCR rectangular vaporizer assembly 395, showing the airflow and temperature patterns 0.4 seconds after activation of the PTCR heater. Air exiting PTCR rectangular vaporizer assembly 395 is heated to a temperature of approximately 150°C to approximately 200°C. Air entering first and second air inlets 340a and 340b is at room temperature (approximately 20°C to approximately 25°C) and mixes with vapor entering the vapor inlet of mouthpiece 335. Aerosol exiting aerosol outlet 342 of mouthpiece 335 is cooled to a temperature of approximately 50°C to approximately 90°C.

[0106] Figure 43 is a perspective, see-through view of mouthpiece 335 attached to PTCR rectangular vaporizer assembly 395, showing the airflow and temperature patterns 0.5 seconds after activation of the PTCR heater. Air exiting PTCR rectangular vaporizer assembly 395 is heated to a temperature of approximately 160°C to approximately 210°C. Air entering first and second air inlets 340a and 340b is at room temperature (approximately 20°C to approximately 25°C) and mixes with vapor entering the vapor inlet of mouthpiece 335. Aerosol exiting aerosol outlet 342 of mouthpiece 335 is cooled to a temperature of approximately 50°C to approximately 90°C.

[0107] FIG. 44 is a perspective, see-through view of mouthpiece 335 attached to PTCR rectangular vaporizer assembly 395, showing the airflow and temperature patterns 1.0 second after activation of the PTCR heater. Air exiting PTCR rectangular vaporizer assembly 395 is heated to a temperature of approximately 160°C to approximately 210°C. Air entering first and second air inlets 340a and 340b is at room temperature (approximately 20°C to approximately 25°C) and mixes with vapor entering the vapor inlet of mouthpiece 335. Aerosol exiting aerosol outlet 342 of mouthpiece 335 is cooled to a temperature of approximately 55°C to approximately 100°C. The difference between the vapor inlet temperature and the aerosol outlet temperature is at least 100°C.

[0108] FIG. 45 is a perspective, see-through view of mouthpiece 335 attached to PTCR rectangular vaporizer assembly 395, showing the airflow and temperature patterns 2.0 seconds after activation of the PTCR heater. Air exiting PTCR rectangular vaporizer assembly 395 is heated to a temperature of approximately 170°C to approximately 220°C. Air entering first and second air inlets 340a and 340b is at room temperature (approximately 20°C to approximately 25°C) and mixes with vapor entering the vapor inlet of mouthpiece 335. Aerosol exiting aerosol outlet 342 of mouthpiece 335 is cooled to a temperature of approximately 60°C to approximately 100°C. The difference between the vapor inlet temperature and the aerosol outlet temperature is at least 100°C.

[0109] FIG. 46 is a perspective, see-through view of mouthpiece 335 attached to PTCR rectangular vaporizer assembly 395, showing the airflow and temperature patterns 3.0 seconds after activation of the PTCR heater. Air exiting PTCR rectangular vaporizer assembly 395 is heated to a temperature of approximately 190°C to approximately 240°C. Air entering first and second air inlets 340a and 340b is at room temperature (approximately 20°C to approximately 25°C) and mixes with vapor entering the vapor inlet of mouthpiece 335. Aerosol exiting aerosol outlet 342 of mouthpiece 335 is cooled to a temperature of approximately 60°C to approximately 100°C. The difference between the vapor inlet temperature and the aerosol outlet temperature is at least 100°C.

[0110] 47 shows the temperature of air exiting the mouthpiece as a function of time for an exemplary vaporizer device equipped with a PTCR heater. The temperature of the air exiting the mouthpiece rises rapidly at a rate of approximately 6,000°C / min between 0 and 0.4 seconds. Between 0.4 and 0.6 seconds, the rate of change of the temperature of the air exiting the mouthpiece slows significantly, reaching a steady-state rate of approximately 188°C / min between 0.6 and 3.0 seconds.

[0111] 48 shows the current response as a function of time for an exemplary vaporizer device equipped with a PTCR heater. Upon activation, the PTCR heater conducts approximately 43 amps until approximately 0.2 seconds after activation. Between 0.2 and 0.3 seconds after activation, the current spikes to a peak current of approximately 47 amps, then reaches a steady-state current of approximately 2 amps approximately 2 seconds after activation.

[0112] FIG. 49 is a top view of a mouthpiece 335 attached to a PTCR rectangular vaporizer assembly 398 with the product cover and cover removed. The heat exchanger elements and conductive coating have also been removed in FIG. 49 to reveal the exposed PTCR material 300. The PTCR material 300 is color-coded to represent the current density two seconds into a transient simulation of air exiting the aerosol outlet 342 of the mouthpiece 335 at a flow rate of 1.4 liters / minute with a 3.7 volt differential voltage applied across the PTCR material 300 positioned between the conductive coatings. Ambient airflow entering the opposite side of the aerosol outlet 342 results in a greater heat load near the ambient air entry side (upstream side) than the opposite side (downstream side). The difference in heat load results in a difference in current density within the PTCR material 300, as shown in FIG. 49. A current density legend is also provided, with a range of 50,000 A / m 2 ~100,000A / m 2 Figure 49 is consistent with the PTCR material principle shown in Figure 1.

[0113] Any of the mouthpieces described above can be coupled to any of the PTCR vaporization assemblies described above. For example, any of the mouthpieces described above can be removably coupled to any of the PTCR vaporization assemblies described above via an interference fit, press fit, snap fit, magnetic coupling, adhesive, and other fastening means. In some embodiments, the mouthpiece can be separated from the PTCR vaporization assembly to replace the vaporizable material contained therein, and then the two can be reconnected.

[0114] In the above description and in the claims, a conjunctive list of multiple elements or features may be followed by phrases such as "at least one of" or "one or more of." The term "and / or" may also appear in a list of two or more elements or features. Such phrases are intended to refer to any of the listed elements or features individually, or any of the listed elements or features in combination with any of the other listed elements or features, unless otherwise specifically implicitly or explicitly contradicted by the context in which they are used. For example, the phrases "at least one of A and B," "one or more of A and B," and "A and / or B" are intended to mean "A only, B only, or both A and B," respectively. A similar interpretation is intended for lists containing more than two items. For example, the phrases "at least one of A, B, and C," "one or more of A, B, and C," and "A, B, and / or C" are intended to mean "A only, B only, C only, both A and B, both A and C, both B and C, or both A, B, and C," respectively. Furthermore, use of the term "based on" above and in the claims is intended to mean "based at least in part on," which may allow for unrecited features or elements.

[0115] The subject matter described herein may be implemented in systems, devices, methods, and / or articles, depending on the desired configuration. The embodiments set forth in the foregoing description do not represent every embodiment consistent with the subject matter described herein. Rather, they are merely some examples consistent with aspects related to the described subject matter. While several variations have been described in detail above, other modifications or additions are possible. In particular, further features and / or variations may be provided in addition to the features and / or variations described herein. For example, the above-described embodiments may be directed to various combinations and subcombinations of the disclosed features and / or combinations and subcombinations of several other features disclosed above. Furthermore, the logic flow illustrated in the accompanying drawings and / or described herein does not necessarily require the particular order shown or sequential order to achieve desired results. Alternative embodiments may also be within the scope of the following claims.

Claims

1. a housing having an air inlet; a heating element within the housing, the heating element including a resistive material with a nonlinear positive temperature coefficient; a heat exchanger thermally coupled to the heating element and positioned to receive the airflow from the air inlet, the heat exchanger configured to transfer heat between the heating element and the airflow to generate a heated airflow, the heated airflow exiting the heat exchanger configured to vaporize a vaporizable material; a cartridge having a first air inlet; Equipped with The cartridge comprises: a reservoir containing the vaporizable material; a wick fluidly connected to the vaporizable material, the wick positioned to receive the heated airflow from the heat exchanger and vaporize the vaporizable material to generate a vapor and / or a first aerosol; a mouthpiece configured to receive the vapor and / or the first aerosol via a vapor inlet; Vaporizer device.

2. a solid vaporizable material positioned to receive the vapor and / or the first aerosol and generate a second aerosol; 10. The vaporizer device of claim 1, wherein the mouthpiece is configured to receive the vapor and / or the second aerosol after the first aerosol has passed through the solid vaporizable material.

3. 3. The vaporizer device of claim 1 or 2, wherein the cartridge is configured to receive the heated airflow through the first air inlet and direct the heated airflow over the wick.

4. 4. The vaporizer device of claim 1, wherein the wick is positioned in the path of the heated airflow between the heating element and the mouthpiece.

5. 5. The vaporizer device of claim 1, wherein the cartridge includes a second air inlet configured to draw a second air flow into the cartridge for mixing with the heated air flow.

6. The vaporizer device of claim 5 , wherein the second air inlet is disposed within the mouthpiece.

7. 7. The vaporizer device of claim 1, wherein the nonlinear positive temperature coefficient resistive material has an electrical resistivity transition zone in which electrical resistivity increases over a temperature range, such that when the heating element is heated above a first temperature within the electrical resistivity transition zone, current from a power source is reduced to a level that limits further temperature increase of the heating element.

8. The vaporizer device of claim 7, wherein the electrical resistivity transition zone begins at a first temperature between 150°C and 350°C.

9. The vaporizer device of claim 8, wherein the electrical resistivity transition zone begins at a first temperature between 220°C and 300°C.

10. 10. The vaporizer device of claim 9, wherein the electrical resistivity transition zone begins at a first temperature between 240°C and 280°C.

11. 11. The vaporizer device of claim 7, wherein the increase in electrical resistivity across the temperature range of the electrical resistivity transition zone has an increase factor of at least 10, the increase factor characterizing the relative change in electrical resistivity between the electrical resistivity at the first temperature associated with the beginning of the electrical resistivity transition zone and the electrical resistivity at a second temperature associated with the end of the electrical resistivity transition zone.

12. 12. The vaporizer device of claim 7, wherein the electrical resistivity transition zone begins at the first temperature, and the electrical resistivity of the heating element at temperatures below the first temperature is between 0.2 Ω cm and 200 Ω cm.

13. a power supply configured to supply a voltage between 3 volts and 50 volts to the heating element; A pressure sensor; a controller coupled to the pressure sensor and configured to detect inhalation and, in response, electrically connect the power source to the heating element; Further provided with 13. A vaporizer device according to any one of claims 1 to 12.

14. The mouthpiece comprises: the vapor inlet and the aerosol outlet; a first plurality of air inlets disposed between the vapor inlet and the aerosol outlet and configured to supply a first plurality of air flows, the first plurality of air flows forming a first vortex, the first vortex having a first axis of rotation and a first direction of rotation about the first axis of rotation; a second plurality of air inlets disposed between the vapor inlet and the aerosol outlet and configured to supply a second plurality of air flows, the second plurality of air flows forming a second vortex, the second vortex having a second axis of rotation and a second direction of rotation about the second axis of rotation; Including, 2. The vaporizer device of claim 1, wherein the first and second plurality of air flows are configured to mix with vapor entering through the vapor inlet to form an aerosol exiting through the aerosol outlet.

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