CONVECTION AND CONDUCTION HEATER FOR A VAPORIZER

A heater assembly designed for use with a vaporizer. The heater assembly including a housing with a heat exchanger. The heat exchanger extends from a first end to a second end. The heat exchanger defines at least one air flow path that extends through the heat exchanger from the first end to the second end. The housing is configured to retain a substance adjacent the second end for heating. A heating element extends around at least a portion of the air flow path with a portion of the heat exchanger positioned between the heating element and the air flow path. The heating element is configured to heat the heat exchanger, and the heat exchanger is configured to transfer heat from the heating element to air flowing through the air flow path from the first end to the second end. Alternatively, the heat exchanger heats as electric current flows through it.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not applicable.

BACKGROUND OF THE INVENTION

There are a variety of different types of vaporizers that are designed to heat a substance until portions of the substance vaporize for inhalation by a user. Some types of commercially available vaporizers are designed to heat the substance via both convection and conduction or radiation. Such vaporizers, however, are often fairly large due to the relatively large space needed to heat air flowing through the vaporizer to a temperature effective to convectively heat the substance to a desired temperature. Many commercially available vaporizers also do not uniformly heat the substance, which may cause an unequal temperature distribution among portions of the substance and overheating of portions of the substance. Overheating the substance may impact the taste of the vaporized substance, e.g., the vaporized substance may taste like it is burnt. Under heating may lead to waste of the substance as not all portions of the substance will be used. Inconsistent temperature distribution may further frustrate the user as the result of vaporization will vary each time the device is used. Further, many commercially available vaporizers may require a relatively high amount of electric power to effectively heat the air for convective heating. Many commercially available vaporizers may also take a long time to heat the substance to the desired temperature necessary for vaporization of desired compounds of the substance, and/or fail to maintain such temperature within a desired range of temperatures over a desired timeframe and range of air flow rates, which may vary from user to user and sometimes even from one session to another due to different application (e.g., preferred usage during work may be different from preferred usage at home).

BRIEF SUMMARY OF THE INVENTION

A heater assembly for a vaporizer in accordance with one aspect of the invention described herein includes a housing with a heat exchanger that extends from a first end to a second end. The heat exchanger defines at least one air flow path that extends through the heat exchanger from the first end to the second end. The housing is configured to retain a substance adjacent the second end for heating. For example, the housing may have a screen that supports the substance above the air flow path through the heat exchanger. A heating element extends around at least a portion of the air flow path with a portion of the heat exchanger positioned between the heating element and the air flow path. The heating element is configured to heat the heat exchanger, and the heat exchanger transfers heat from the heating element to air flowing through the air flow path from the first end to the second end.

In some embodiments, the heating element may comprise a resistance wire that is wrapped around at least a portion of an outer wall of the heat exchanger. The heat exchanger may include an electrically non-conductive insert coupled to the outer wall. The resistance wire may engage the insert at a location where the resistance wire changes direction. The insert may reduce the likelihood of short circuits at locations where the resistance wire bends around edges of the heat exchanger. For example, if the heat exchanger includes an anodized outer surface (for electrical isolation) that may be susceptible to damage along edges of the heat exchanger, the resistance wire may engage the insert at locations where the resistance wire changes direction so that the resistance wire is not in contact with an edge of the anodized outer surface. The resistance wire may have a first end and a second end. The resistance wire may extend from the first end through a channel in the insert toward the second end of the heat exchanger. The wire may extend from the channel around the outer wall in a helical manner toward the first end of the heat exchanger and the second end of the wire. The insert may be formed from a ceramic material. The heater assembly may include a microcontroller configured to monitor a resistance of the resistance wire if the resistance of the wire changes with its temperature. The microcontroller may be configured to determine when air is flowing through the air flow path based on changes in the resistance.

In some embodiments, the resistance wire may include a series of spaced apart rings each wrapped around at least a portion of the outer wall of the heat exchanger with each ring connected to a first electrical lead and a second electrical lead. In other embodiments, the resistance wire may extend from a first end around a portion of the outer wall on one side of the heat exchanger toward the second end of the heat exchanger and then around a portion of the outer wall on an opposite side of the heat exchanger toward the first end of the heat exchanger and a second end of the wire.

In some embodiments, the heating element may be at least one of a heater that is wrapped around at least a portion of an outer surface of the heat exchanger, a ceramic heater, a resistance wire embedded in ceramic, a positive temperature coefficient heater, a negative temperature coefficient heater, a film printed conductor on an outer surface of the heat exchanger, or a conductive material that is joined to the outer surface of the heat exchanger, for example, by laser sintering.

In some embodiments, the air flow path through the heat exchanger may comprise a plurality of channels extending through the heat exchanger from the first end to the second end. The heating element may extend around at least a portion of each of the channels with a portion of the heat exchanger positioned between the heating element and each of the channels.

In some embodiments, an outer surface of the heat exchanger may be at least one of anodized aluminum or ceramic. The outer surface of the heat exchanger may have an electrical resistivity of at least 400 Ω*cm. The heat exchanger may be a material with a high thermal conductivity and/or a high electrical resistivity, e.g., a material with a thermal conductivity that is equal to or greater than 30 W/m*K and/or an electrical resistivity of at least 400 Ω*cm. The heat exchanger may also be formed from a material with a high thermal conductivity that is coated with a material having a high electrical resistivity or anodized so that the surface of the material in contact with the heating element has a high electrical resistivity.

In some embodiments, the housing may define a filling chamber configured to receive the substance for heating. The filling chamber may be configured to receive air exiting the air flow path at the second end of the heat exchanger. The housing may define an outlet through which the filling chamber is accessible. A temperature sensor may be positioned adjacent the filling chamber. The temperature sensor may be configured to sense a temperature within the filling chamber, as this temperature is indicative of whether the substance in the filling chamber is being vaporized in a desired manner, and the sensed temperature may be utilized to adjust operation of the heating element. The housing may have a container defining the filling chamber. The container may be formed integrally with the heat exchanger. The heat exchanger may be configured to conductively heat the container.

In some embodiments, a second heating element may extend around at least a portion of the filling chamber. The second heating element may be configured to conductively heat the container. The second heating element and/or the heating element may comprise a heater that is wrapped around at least a portion of the outer surface of the container, a ceramic heater, a resistance wire embedded in ceramic, a positive temperature coefficient heater, a negative temperature coefficient heater, a film printed conductor on the outer surface of the container, or a conductive material that is joined to the outer surface of the container, for example, by laser sintering.

In some embodiments, the heat exchanger may be formed from two or more separate components that are joined together.

In some embodiments, the heater assembly may include a sensor configured to measure at least one of a pressure of the air flow path or a mass of air flowing through the air flow path. A microcontroller electrically coupled to the sensor is configured to determine when air is flowing through the air flow path based on a signal from the sensor. The microcontroller may be configured to send electric power to the heating element when it determines that air is flowing through the air flow path.

A heater assembly for a vaporizer in accordance with another aspect of the invention described herein includes a housing with a heat exchanger that extends from a first end to a second end. The heat exchanger defines at least one air flow path that extends through the heat exchanger from the first end to the second end. The housing is configured to retain a substance adjacent the second end for heating. A first electrical lead is connected to a first portion of the heat exchanger and a second electrical lead is connected to a second portion of the heat exchanger. The first and second electrical leads are configured to conduct electric current that flows through the heat exchanger from the first portion to the second portion. The heat exchanger is configured to increase in temperature as the electric current flows through the heat exchanger. The heat exchanger is configured to transfer heat to air flowing through the air flow path from the first end to the second end. The first and second portions of the heat exchanger to which the electrical leads are connected may be adjacent first and second ends of the heat exchanger or first and second sides of the heat exchanger. In some embodiments, the air flow path through the heat exchanger may comprise a plurality of channels extending through the heat exchanger from the first end to the second end.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

A heater assembly for a vaporizer in accordance with an embodiment of the invention described herein is identified generally as10inFIGS.1-4. As described in more detail below, the heater assembly10may be configured to quickly and efficiently heat a substance for vaporization. The heater assembly10may further heat such substance relatively uniformly so that portions of the substance are not overheated while other portions of the substance remain under heated. The heater assembly10may also have a relatively small size or form factor allowing it to be integrated into a vaporizer that is relatively small. The heater assembly10may be used in any type of vaporizer, including a handheld vaporizer or a desktop vaporizer. The heater assembly10may be configured to heat a substance so that compounds of the substance are vaporized for inhalation by a user.

Referring toFIG.1, the heater assembly10includes a housing12with an outer shell14that is generally shaped like a cuboid in the embodiment shown inFIG.1, although the outer shell14may have any suitable shape. The outer shell14includes a top wall18, side walls20a-d(FIG.4), and a base22(FIG.2). A filling chamber24of the housing12is accessible through an opening26in the top wall18. The filling chamber24is configured to receive a substance for heating and subsequent vaporization of compounds of the substance. The outer shell14may include one or more openings (not shown) in any of the top wall18, side walls20a-d,or base22to allow air to enter the outer shell14, as described in more detail below.

Referring toFIG.3, half of the outer shell14is not shown so that internal details of the heater assembly10are visible. An outer shroud36is positioned within the outer shell14. As described in more detail below, the outer shroud36is positioned around an inner shroud38, a heat exchanger54(FIG.7), and a container78(FIG.7) of the heater assembly10. A groove42extending around the outer shroud36receives an intermediate wall44of the outer shell14to position the outer shroud36with respect to the outer shell14. An upper portion of the outer shroud36extends above the intermediate wall44and defines an opening or outlet46that is generally aligned with the opening26in the top wall18. The filling chamber24is accessible through the outlet46.

FIG.4shows the top wall18of the heater assembly10showing the filling chamber24accessible through the opening26in the top wall18and the outlet46of the outer shroud36.

Referring toFIG.5, a cross-sectional view of the heater assembly10, the inner shroud38has a bottom wall50and a generally cylindrical side wall52that define a receptacle receiving a heat exchanger54, which is described below in connection withFIGS.7-9. The heat exchanger54is radially spaced inward from the side wall52of the inner shroud38to define an annular gap56between the heat exchanger54and side wall52. As described above, the outer shroud36is mounted to the intermediate wall44. The outer shroud36has a generally cylindrical side wall58extending downward from the intermediate wall44toward the base22. The inner shroud38is radially spaced inward from the outer shroud36to define an annular gap60between the inner shroud38and outer shroud36.

A temperature sensor116(FIG.16) may be positioned in or near the heat exchanger54. As described in more detail below, the heat exchanger54has a plurality of channels, one of which is identified as66, extending axially through the heat exchanger54from adjacent the inner shroud38to adjacent the filling chamber24. The temperature sensor116may be positioned in one of the channels66adjacent the filling chamber24(e.g., as shown inFIG.8) so that it can sense a temperature within the filling chamber24or an area adjacent the filling chamber24. As described below, the temperature sensed by the temperature sensor116may be used to control when a heating element of the heater assembly10is powered by a power source. The temperature sensor116may be, for example, a type-K thermocouple, a negative temperature coefficient thermistor (NTC), or a platinum measuring resistor (PT100/PT1000).

FIG.6shows an air flow path70through the housing12when air is drawn through outlet46to vaporize a substance. The air enters the housing12through one or more of the openings (not shown) in the outer shell14and/or through gaps between different portions of the outer shell14, e.g., through a gap between the base22and side walls20a-d.The air enters the space between the outer shell14and the outer shroud36, and then flows around a lower edge of the outer shroud36into the annular gap60between the outer shroud36and the inner shroud38. The air flows upward through the annular gap60and around an upper edge of the inner shroud38. The air flow path70makes a 180 degree turn at the upper edge of the inner shroud38and then flows downward through the annular gap56between the inner shroud38and the heat exchanger54. A heating element72is wound around an outer surface of the heat exchanger54, as described in more detail below with reference toFIGS.7-9. The heating element72heats the air as it flows downward through the annular gap56. The air flow path70extends downward along the length of the heat exchanger54until it reaches the bottom of the heat exchanger54. The air flow path70then extends radially inward through a space74between the bottom of the heat exchanger54and the bottom wall50of the inner shroud38. The air flow path70then turns 90 degrees upward through the plurality of channels66extending through the heat exchanger54. The plurality of channels66define a plurality of air flow paths70through the heat exchanger54. The heat exchanger54is heated by the heating element72, and as the air flows adjacent to and through the heat exchanger54, the air is heated by the heat exchanger54. At the top of the heat exchanger54, the air flow path70exits the heat exchanger54and enters the filling chamber24. As the air flows through the filling chamber24, it convectively heats a substance positioned in the filling chamber24. The air and any vaporized compounds of the substance travel upward from the filling chamber24and through the outlet46. While not shown in the drawings, an inhalation structure (e.g., a housing with a tube or mouthpiece) may be joined to the top wall18for receiving air and vaporized portions of the substance exiting the outlet46and routing the air and vaporized portions of the substance into a user's mouth or storage device (e.g., a bag). The air flow path70described above and shown inFIG.6is exemplary only. The heater assembly10may be structured so that the air flowing through the housing takes a different path as it is heated by the heat exchanger54. Further, the directional terms (e.g., “upward” and “downward”) used herein describe the exemplary air flow path70when the heater assembly10is in the orientation shown inFIG.6. When the heater assembly10is positioned in a different orientation, the direction of the air flow path may be different from what is described herein.

The heat exchanger54and a container78of the housing12are described below making reference toFIGS.7-9. The heat exchanger54and container78are shown as being integral with each other. In alternative embodiments, however, the container78may be formed separately from the heat exchanger54and positioned on top of the heat exchanger54within the outer shroud36(FIG.5). The heat exchanger54has an outer wall80that extends from a first end82to a second end84of the heat exchanger54. The outer wall80is generally cylindrical and defines, at least in part, the channels66(and associated air flow path70) extending axially through the heat exchanger54. A helical groove86extends around the outer wall80from adjacent the first end82to adjacent the second end84. The heating element72is positioned in the helical groove86. The heat exchanger54and container78may, for example, be milled from a single block of material. The heat exchanger54may also include an insert, similar to that described below for the embodiment shown inFIGS.10-14, that is positioned within the outer wall80to define the channels66. The channels66may be drilled holes extending through the heat exchanger54with the outer wall80generally extending around the holes.

The heat exchanger54may be formed from a material with a relatively high thermal conductivity so that heat from the heating element72is readily conducted through the material to the surfaces surrounding the channels66and the air flowing through the channels66. For example, the heat exchanger54may be formed from a metal, such as aluminum or titanium, or any other suitable material including a ceramic material, such as magnesium dioxide or zirconium dioxide. The heat exchanger54may be formed from a material with a thermal conductivity that is equal to or greater than approximately 1 W/m*K, and in some embodiments equal to or greater than 30 W/m*K.

The combined surface area of the surfaces surrounding the channels66through the heat exchanger54enhances the ability of heat exchanger54to transfer heat to the air flowing through the air flow path70. For example,FIG.9shows approximately20separate channels66extending through the heat exchanger54. Each of these channels66forms a part of the air flow path70of the air flowing through the heat exchanger54. The surfaces of the heat exchanger54surrounding each of these channels66are heated as heat is transferred from the heating element72through the heat exchanger54to the surfaces. The heated surfaces surrounding each of the channels66heat the air as it flows through the channels66. By having a plurality of channels66, the surface area of the heat exchanger54that is adjacent the air flow path70is relatively large and therefore able to transfer heat to the air flowing through the air flow path70relatively quickly and efficiently. Providing the channels66may transfer heat to the air flowing through the heat exchanger54at a greater rate than, for example, a heat exchanger with an air flow path that includes only one channel. Further, the channels66allow the heat exchanger54to have a relatively small size or profile while still heating the air flowing through it relatively quickly and efficiently. For example, the heat exchanger54may transfer heat to the air flowing through it at the same rate as a typical heat exchanger much larger in size. The heat exchanger54may also require less energy to heat an airflow to a specific temperature than a typical heat exchanger.

The outer surface88of the heat exchanger54, including the surfaces defining the groove86, may have a relatively high electrical resistivity. For example, an electrical resistivity of between approximately 108to 1010Ω*cm, or at least 400 Ω*cm. In particular, if the heating element72is a resistance wire that conducts electricity, at least the portions of the outer surface88that contact the heating element72may have a relatively high electrical resistivity so that electric current from the heating element72is not appreciably conducted through the heat exchanger54and container78. For example, if the heat exchanger54is formed from aluminum, the outer surface88may be anodized. The outer surface88may also be coated with a material that has a relatively high electrical resistivity such as a ceramic material or a tape formed from polyimide film with a silicon adhesive, including Kapton® tape.

The heating element72is a resistance wire heating element that, as described above, is wrapped around the outer wall80and positioned in the helical groove86. The heating element72extends around the channels66extending through the heat exchanger54with portions of the heat exchanger54positioned between the heating element72and the channels66. The heat exchanger54includes an insert90that is positioned within an axial groove91(FIGS.8-9) extending from the first end82to the second end84. The insert90is designed to minimize short circuits at locations where the heating element72bends around edges of the heat exchanger54as it is routed around and through the heat exchanger54. If the outer surface88of the heat exchanger54is anodized, the anodized surface at the edges may be susceptible to damage and loss of electrical isolation. Thus, the insert90may be formed from a ceramic material with a high electrical resistivity that reduces the likelihood that the heating element72will short circuit through the heat exchanger54. In some embodiments, the heating element72may be embedded within the outer wall80of the heat exchanger54such that the heating element72extends around the channels66. In some embodiments, the heating element72may be any type of heating element that is configured to wrap around at least a portion of the heat exchanger54, including a flexible printed heater, a ceramic heater, a resistance wire embedded in ceramic, a positive temperature coefficient heater, a negative temperature coefficient heater, a film printed conductor on the outer surface88of the heat exchanger54, or a conductive material that is joined to the outer surface88of the heat exchanger54, for example, by laser sintering.

Referring toFIGS.7and8, the heating element72has a first end92and a second end94. The heating element72extends from the first end92through a channel96(FIG.8) in the insert90upward toward the second end84of the heat exchanger54. The heating element72exits the channel96and bends 90 degrees toward the outer surface88of the heat exchanger54. As shown inFIG.7, the heating element72then travels through the groove86around the outer wall80in a helical manner from the second end84of the heat exchanger54toward the first end82of the heat exchanger54. The heating element72then exits the groove86at the insert90and wraps around a portion of the insert90before terminating at the second end94of the heating element72. The heating element72may take other paths around the heat exchanger54, including that path described below in connection with the embodiment shown inFIGS.10-14. For example, the heating element may be structured so that it includes a series of spaced apart rings extending around the outer surface of the heat exchanger. Each of the rings may be connected to adjacent rings via a segment of wire extending between adjacent rings.

The container78is formed integrally with the heat exchanger54and extends upwardly from the heat exchanger54. As shown inFIG.8, the container78has an outer wall98extending upwardly from the outer wall80of the heat exchanger54. The container78has a first end100at the second end84of the heat exchanger54and a second end102. An outlet104of the container78is at the second end102. The outlet104is aligned with the outlet46of the outer shroud36(FIG.5). At the first end100of the container78, the inner surface of the outer wall98defines a groove106. The groove106may receive, for example, a screen108that supports a substance within the filling chamber24above the heat exchanger54and generally prevents the substance from entering the heat exchanger54. The container78defines the filling chamber24that is positioned above the heat exchanger54, with the filling chamber24being sized and configured to retain a substance for vaporization, as described above. The filling chamber24is positioned above the channels66in the heat exchanger54so that heated air from the heat exchanger54flows upward through the filling chamber24when air is drawn through the heater assembly10. The channels66are generally spaced homogeneous apart across the width of the filling chamber24to promote generally uniform heating of the substance in the filling chamber24.

When the heat exchanger54is heated by the heating element72, the heat exchanger54conductively heats the container78, and the container78heats the substance positioned within the filling chamber24via conduction (for material positioned in contact with the inner surface of the container78) and via radiation (for material spaced apart from the inner surface of the container78). If the heat exchanger54and the container78are formed separately, they may abut so that heat is conducted from the heat exchanger54to the container78. If the heating element72is powered to heat the heat exchanger54prior to air being drawn or pumped through the heat exchanger54, the substance within the filling chamber24may be preheated by the conductive and radiative heat transfer described above to a desired temperature that is near or at the vaporization temperature of compounds within the substance desired for vaporization. Such substance may then be convectively heated by the heated air flowing through the heat exchanger54and the filling chamber24, as described above. The combination of the conductive and radiative preheating of the substance and the convective heating of the substance when air is drawn through the filling chamber24may improve the experience of using a vaporizer incorporating the heater assembly10by (1) heating the substance relatively quickly via the conductive and radiative preheating so that the user does not need to wait long to use the vaporizer, and (2) heating the substance in a relatively uniform manner to a desired temperature via the convective heating so that significant portions of the substance are not overheated above a desired temperature while other portions are under heated.

A microcontroller110, shown inFIG.16, may be configured to send electric power from a power source112to the heating element72. The power source112may be, for example, a battery or mains power. The microcontroller110may receive instructions from a user input device114, for example a touchscreen display panel or regular buttons, associated with the heater assembly10. The microcontroller110may also receive instructions wirelessly from a mobile device or computer. The microcontroller110may be programmed to cause the heating element72to be powered at desired times so that it reaches a desired temperature based on the instructions received. The microcontroller110may also receive temperature readings from a temperature sensor116and use such temperature readings to determine when, and for how long, to power the heating element72. It may be desired to power the heating element72as air is drawn through the heater assembly10so that the air is heated to a desired temperature by the heat exchanger54. The microcontroller110may also be configured to monitor a resistance of the heating element72and determine when air is flowing through the air flow path70by changes in such resistance. The determination of when air is flowing through the air flow path may further be used to determine when to power the heating element72. A pressure sensor118or an air flow sensor120may also be used to determine when air is flowing through the air flow path70. The microcontroller110may receive a signal from the pressure sensor118or air flow sensor120. For example, when air is drawn through the heater assembly10by a user, the pressure sensor118may detect a pressure differential or the air flow sensor120may detect a mass of air flowing through the air flow path70. The microcontroller110may use the pressure differential or air mass measurement to determine whether to power the heating element72.

The heater assembly10may be used with a vaporizer that is configured to have a user draw air through the heat exchanger54and filling chamber24by drawing air through a tube, mouthpiece, or other device connected to the top wall18. The heater assembly10may also be used with a vaporizer having an air pump that is configured to pump air through the heat exchanger54and filling chamber24. The heater assembly10may be configured so that a storage device is mounted above the filling chamber24with the storage device capable of receiving air and vaporized portions of the substance as the air pump operates. The heater assembly10may further be used with a vaporizer that is user-configurable for use in connection with either pumping air through the heat exchanger54or having air passively drawn through the heat exchanger54by a user drawing air through the outlet46.

An alternative embodiment of heat exchanger200and container202that may be used with the heater assembly10is described with reference toFIGS.10-14. As shown inFIG.11, the heat exchanger200has an outer wall204extending from a first end206to a second end208. The heat exchanger200has an insert209(FIG.10) positioned in a chamber defined by the outer wall204. The outer wall204of the heat exchanger200has two helical grooves210,212(FIG.11) extending from the first end206to the second end208. The helical grooves210,212receive a heating element214that may operate in a similar manner as the heating element72described above. The outer wall204and insert209of the heat exchanger200may be made from any of the materials described above for heat exchanger54, and the outer surface of the outer wall204may be anodized or coated with a material having a high electrical resistivity, as described above in connection with heat exchanger54.

The heating element214has a first end216and a second end218, shown inFIG.11. The heating element214extends from the first end216around a post220and into the second groove212. The heating element214wraps around the outer wall204within the second groove212from the first end206to the second end208. At the second end208, the heating element214exits the second groove212and wraps 180 degrees around a post222. From the post222, the heating element214enters the first groove210and wraps around the outer wall204within the first groove210toward the first end206. At the first end206, the heating element214wraps around a post (not shown) similar to post220and terminates at its second end218.

FIG.12shows a plurality of channels226extending through the insert209. The channels226form an air flow path through the heat exchanger200in a similar manner as the channels66described above. The channels226further function to increase the surface area of the heat exchanger200that is exposed to the air flowing through it in order to efficiently transfer heat to the air, as described above in more detail with respect to heat exchanger54.

FIG.13shows that the container202is formed integrally with the heat exchanger200and has an outer wall230extending upwardly from the heat exchanger200. The container202defines a filling chamber232configured to receive a substance in a similar manner as the container78described above. A groove234formed in an inner surface of the outer wall230receives a screen235to support a substance within the filling chamber232above the insert209.

Referring toFIG.14, the insert209has a central hub236with a plurality of spokes238radially extending outward from the hub236. The spokes238are generally spaced equidistant from each other circumferentially to create the channels226. The heat exchanger200may be manufactured from two or more separate components. For example, the outer wall204may be manufactured from one component, and the insert209manufactured from a separate component. After the outer wall204and insert209are manufactured, they may be joined to form the heat exchanger200, as shown inFIG.10. Manufacturing the outer wall204and insert209from separate components may simplify manufacturing of the heat exchanger and lower manufacturing costs. Other than as described herein, the heat exchanger200and container202may be structured and function in substantially the same manner as the heat exchanger54and container78described above.

Referring now toFIG.15, another alternative embodiment of heater assembly is identified generally as300. Heater assembly300is substantially similar to heater assembly10described above except as described herein. The difference between heater assembly300and heater assembly10is that heater assembly300includes two heating elements, a first heating element302that is substantially similar to the heating element72of heater assembly10, and a second heating element304. The second heating element304is wrapped around at least a portion of, or all of, an outer surface306of a container308, and a filling chamber310defined by the container308. The container308is substantially similar to the container78described above except for the second heating element304. The second heating element304may be used to conductively heat the container308, which transfers the heat via conduction and radiation to a substance within the filling chamber310. The second heating element304may be used to preheat the substance within the filling chamber310prior to a user drawing air through the heater assembly300, in a similar manner as described above with respect to conductive and radiative heating of the substance within the filling chamber24described above. A microcontroller (not shown) of the heater assembly300may be programmed to power the first and second heating elements302and304individually to heat the substance to a desired temperature within a desired timeframe and to maintain such temperature for a desired length of time. Temperature readings from one or more temperature sensors, like the sensor116described above, may be used by the microcontroller to determine when to power the first and second heating elements302and304.

The second heating element304may be any type of heating element configured to wrap around at least a portion of the container308, including a flexible printed heater, a ceramic heater, a resistance wire embedded in ceramic, a positive temperature coefficient heater, a negative temperature coefficient heater, a film printed conductor on the outer surface306of the container308, or a conductive material that is joined to the outer surface306of the container308, for example, by laser sintering.

FIG.17shows an alternative embodiment of heater assembly400, which is substantially the same as the heater assembly10, except that the heater assembly400includes a sensor402in fluid communication with an air flow path404through the heater assembly400. The sensor402may be (1) a differential pressure sensor that is configured to measure the gauge pressure of the air flow path404, or the difference in pressure between the air flow path404and the ambient air surrounding the heater assembly400, (2) an absolute pressure sensor that is configured to measure the absolute pressure of the air within the air flow path404, or (3) an air flow sensor that is configured to measure a mass of air flowing in the air flow path404within a particular time frame. The pressure sensor118and air flow sensor120described above and shown inFIG.16may be configured in the same manner as the sensor402shown inFIG.17. The sensor402may be configured to sense when air is flowing through the air flow path404, as described above in connection withFIG.16, and send a signal to the microcontroller, which may determine when air is flowing through the air flow path404and whether to power the heating element based on the signal.

FIGS.18A and18Bshow an alternative embodiment of heat exchanger500and container502that may be used with any of the heater assemblies10,300, or400described herein. The heat exchanger500has an outer wall504extending from a first end506to a second end508. The outer wall504of the heat exchanger500has a series of spaced apart grooves510a-eextending around the outer wall504. The grooves510a-bare connected on a first side512of the heat exchanger500, as shown inFIG.18B, via a groove510f.The grooves510c-dare also connected on the first side of the heat exchanger500via a groove510g.The grooves510b-care connected on a second side514of the heat exchanger500via a groove510h,and the grooves510d-eare connected on the second side514via a groove510i.The grooves510a-ireceive a heating element516that may operate in a similar manner as the heating element72described above. The outer wall504may be made from any of the materials described above for heat exchanger54, and the outer surface of the outer wall504may be anodized or coated with a material having a high electrical resistivity, as described above in connection with heat exchanger54.

The heating element516has a first end518and a second end520shown inFIG.18A. The heating element516extends from the first end518into the groove510aand around the outer wall504from the second side514to the first side512. The heating element516extends from the groove510athrough the groove510fand into the groove510bmaking a 180 degree turn back toward the second side514. The heating element516continues on a similar path through the grooves510h,510c,510g,510d,and510ion one side of the heat exchanger500toward the second end508. The heating element516then enters the groove510eand extends substantially around the perimeter of the outer wall504to the groove510i.The heating element516then extends through the grooves510d,510g,510c,510h,510b,510f,and510aon the opposite side of the heat exchanger before terminating at its second end520. Other than as described herein, the heat exchanger500and container502may be structured and function in substantially the same manner as the heat exchanger54and container78described above.

FIGS.19A and19Bshow another alternative embodiment of heat exchanger600and container602that may be used with any of the heater assemblies10,300, or400described herein. The heat exchanger600has an outer wall604extending from a first end606to a second end608. The outer wall604of the heat exchanger600has a series of spaced apart grooves610a-eextending around the outer wall604. Each of the grooves610a-ereceives a heating element, one of which is identified as612. The heating elements612received in the grooves610a-eare a series of spaced apart rings each wrapped around the outer wall604. The heating elements612may operate in a similar manner as the heating element72described above. The outer wall604may be made from any of the materials described above for heat exchanger54, and the outer surface of the outer wall604may be anodized or coated with a material having a high electrical resistivity, as described above in connection with heat exchanger54.

A first electrical lead614extends from the first end606toward the second end608on one side of the heat exchanger600. The first electrical lead614may be positioned within a groove formed in the outer wall604that extends transverse to the grooves610a-e.The first electrical lead614is electrically connected with each of the heating elements612. A second electrical lead616, best shown inFIG.19B, also extends from the first end606toward the second end608. The second electrical lead616may also be positioned within a groove formed in the outer wall604that extends transverse to the grooves610a-e.The second electrical lead616is electrically connected with each of the heating elements612on an opposite side of the heat exchanger600as the first electrical lead614. A voltage may be applied across the first and second electrical leads614and616causing electrical current to flow through each of the heating elements612, which generate heat that is transferred to the heat exchanger600in a similar manner as described above with respect to heat exchanger54. Other than as described herein, the heat exchanger600and container602may be structured and function in substantially the same manner as the heat exchanger54and container78described above.

Referring toFIG.20, another alternative embodiment of heat exchanger700and container702is shown that may be used with any of the heater assemblies10,300, or400described herein. The heat exchanger700has an outer wall704extending from a first end706to a second end708. A first electrical lead710is connected to the outer wall704at the first end706, and a second electrical lead712is connected to the outer wall704at the second end708. The first and second electrical leads710and712are configured to conduct electric current that flows through the heat exchanger700from the first end706to the second end708when a voltage is applied to the leads. The heat exchanger700is made from a material with a relatively high electrical resistivity that causes it to increase in temperature as the electric current flows through it from the first end706to the second end708. The heat exchanger700further is made from a material with a relatively high thermal conductivity so that the heat generated by the electric current is conducted throughout the heat exchanger, and in particular to the surfaces surrounding the channels714extending through the heat exchanger. As described above in connection with the heat exchanger54, the heated surfaces surrounding the channels714transfer heat to air flowing through the channels from the first end706to the second end708. The heat exchanger700also transfers heat to the container702to conductively heat a material within the container702. While the first and second electrical leads710and712are shown at first and second ends706and708of the heat exchanger, respectively, instead of being at opposite ends of the heat exchanger, the first and second electrical leads710and712may be on opposite sides of the heat exchanger. For example, the first electrical lead710may be positioned on the right side700aof the heat exchanger700as shown inFIG.20, and the second electrical lead712may be positioned on the left side700bas shown inFIG.20. The first and second electrical leads710and712may further be positioned on opposite sides and ends of the heat exchanger. For example, the first electrical lead710may be positioned as shown inFIG.20, and the second electrical lead712may be positioned on the left side700bas shown inFIG.20at the second end708. The heat exchanger700may be made from any suitable material, which may include nichrome or graphite. Other than as described herein, the heat exchanger700and container702may be structured and function in substantially the same manner as the heat exchanger54and container78described above.

The heater assembly10may be used with any type of vaporizer, including handheld or desktop vaporizers. According to one exemplary method of using the heater assembly10, a substance is placed in the filling chamber24and the microcontroller110receives instructions to heat the substance to a desired temperature. The microcontroller110causes the heating element72to be powered by the power source112. The heating element72heats the heat exchanger54, container78, and substance via conduction and radiation in the manner described above. When the temperature sensor116senses that a desired preheating temperature is reached at or adjacent the filling chamber24or a given amount of time has elapsed, the microcontroller110may cause the vaporizer to indicate to a user that the vaporizer is ready for use. The user may draw air and the vaporized substance through an inhalation structure (not shown) that is attached to the top of the heater assembly10. As the user draws air through the heat exchanger54, the air is heated as described above to convectively heat the substance as the air flows through the filling chamber24.

The heater assembly300may be used in a substantially similar manner as the heater assembly10with the second heating element304of the heater assembly300being used to preheat the substance within the filling chamber310.

From the foregoing it will be seen that this invention is one well adapted to attain all ends and objectives herein-above set forth, together with the other advantages which are obvious and which are inherent to the invention.

Since many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matters herein set forth or shown in the accompanying drawings are to be interpreted as illustrative, and not in a limiting sense.

While specific embodiments have been shown and discussed, various modifications may of course be made, and the invention is not limited to the specific forms or arrangement of parts and steps described herein, except insofar as such limitations are included in the following claims. Further, it will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims.