Electronic vaping device, battery section, and charger

A battery section of an electronic vaping device may include a housing extending in a longitudinal direction, the housing having a first end and a second end, a power supply in the housing, a control circuit in the housing, and a conductive contact assembly at the second end of the housing, the contact assembly electrically connecting the power supply and the control circuit. The contact assembly is configured to receive external power and at least one command.

BACKGROUND

Field

The present disclosure relates to an electronic vaping or e-vaping device.

Description of Related Art

An e-vaping device includes a heater element which vaporizes a pre-vapor formulation to produce a “vapor.”

The e-vaping device includes a power supply, such as a rechargeable battery, arranged in the device. The battery is electrically connected to the heater, such that the heater heats to a temperature sufficient to convert the pre-vapor formulation to a vapor. The vapor exits the e-vaping device through a mouthpiece including at least one outlet.

SUMMARY

At least one example embodiment relates to a battery section of an electronic vaping device.

In at least one example embodiment, a battery section of an electronic vaping device may comprise a housing extending in a longitudinal direction, the housing having a first end and a second end, a power supply in the housing, a control circuit in the housing, and a conductive contact assembly at the second end of the housing, the contact assembly electrically connecting the power supply and the control circuit, the contact assembly configured to receive external power and at least one command.

In at least one example embodiment, the control circuit is configured to detect at least one of a change in resistance and a change in capacitance so as to detect the at least one command.

In at least one example embodiment, the contact assembly comprises a charge anode and a charge cathode. The control circuit comprises a switch configured to electrically separate the charge cathode from a common ground plane.

In at least one example embodiment, the contact assembly comprises a first contact and a second contact insulated from the first contact. One of the first contact and the second contact is generally ring-shaped and one of the first contact and the second contact forms at least a portion of an end wall of the battery section. The end wall extends generally transverse to the longitudinal direction. The first contact may be the end wall and the second contact may be generally ring-shaped, and may extend about a perimeter of the end wall. The end wall may be substantially opaque.

In at least one example embodiment, the contact assembly may further comprise an end cap housing configured to hold the first contact therein, the end cap housing including at least one slot. The second contact may be integrally formed with at least one tab extending in the longitudinal direction. The at least one tab may be configured to be received in the at least one slot. The end cap housing may include a generally cylindrical sidewall. The sidewall defining an orifice extending through the end cap housing. A first portion of the generally cylindrical sidewall is received within the housing at the second end thereof. A second portion of the sidewall is not within the housing. The second portion may be substantially transparent. The end wall may include a printed circuit board.

In at least one example embodiment, at least one of the first contact and the second contact may be magnetic. At least one of the first contact and the second contact is formed of at least one of stainless steel, gold, or silver.

At least one example embodiment relates to an electronic vaping device.

In at least one example embodiment, an electronic vaping device comprises a housing extending in a longitudinal direction, the housing having a first end and a second end, a power supply in the housing, a control circuit in the housing, a conductive contact assembly at the second end of the housing, a reservoir configured to contain a pre-vapor formulation, and a heater configured to heat the pre-vapor formulation, the heater electrically connected to the power supply. The contact assembly electrically connects the power supply and the control circuit. The contact assembly may be configured to receive external power and at least one command.

In at least one example embodiment, the control circuit is configured to detect at least one of a change in resistance and a change in capacitance so as to detect the at least one command.

In at least one example embodiment, the contact assembly comprises a charge anode and a charge cathode. The control circuit comprises a switch configured to electrically separate the charge cathode from a common ground plane. The contact assembly comprises a first contact and a second contact insulated from the first contact. The second contact may be generally ring-shaped and the first contact may form at least a portion of an end wall. The end wall of the battery section may extend generally transverse to the longitudinal direction.

In at least one example embodiment, the contact assembly further comprises an end cap housing configured to hold the first contact therein. The end cap housing may include at least one slot. The second contact may be integrally formed with at least one tab extending in the longitudinal direction. The at least one tab is configured to be received in the at least one slot.

In at least one example embodiment, the electronic vaping device includes a battery section and a first section. The battery section may contain the power supply, the control circuit, and the conductive contact assembly. The first section may contain the reservoir and the heater

At least one example embodiment relates to a USB charger.

In at least one example embodiment, a USB charger comprises a housing. The housing includes a top wall having a charging slot therein, a first charger contact in the charging slot, a second charger contact in the charging slot, a bottom wall opposite the top wall, and at least one sidewall between the top wall and the bottom wall. The charging slot may be configured to receive an end of the electronic vaping device. The charger also includes at least one magnet adjacent the charging slot. The charger may also include a light pipe surrounding the charging slot and extending from the charging slot to an external surface of the USB charger. The light pipe may be configured to communicate and/or transmit light from an electronic vaping device to the external surface of the USB charger indicate charge status of the electronic vaping device. The housing defines an internal compartment. The charger may further comprise charger circuitry contained within the internal compartment. The charger circuitry is in communication with the first charger contact and the second charger contact.

At least one example embodiment relates to a battery section of an electronic vaping device.

In at least one example embodiment, the battery section comprises a housing extending in a longitudinal direction, the housing having a first end and a second end, a power supply in the housing, a conductive contact assembly at the second end of the housing, the contact assembly electrically connecting the power supply and the control circuit, and a control circuit in the housing configured to detect at least one of a change in resistance and a change in capacitance so as to detect input of the at least one command. The contact assembly is configured to receive external power and at least one command. The contact assembly may include a charge anode and a charge cathode. The control circuit comprises a switch configured to electrically separate the charge cathode from a common ground plane.

At least one other example embodiment provides an electronic vaping device including a battery section. The battery section includes: a first housing extending in a longitudinal direction; a power supply in the first housing, the power supply configured to provide power to a heater coil when the battery section is engaged with a cartridge section including a reservoir and the heater coil; and a control circuit including a resistance measurement circuit and a controller. The control circuit is configured to: measure an initial resistance of the heater coil in the analog domain; calculate a reference resistance of the heater coil in the digital domain based on the measured initial resistance; measure a current resistance of the heater coil in response to detection of a puff event; calculate a percentage change in resistance of the heater coil based on the measured current resistance and the reference resistance of the heater coil; and control power to the heater coil based on the calculated percentage change in resistance of the heater coil.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

Some detailed example embodiments are disclosed herein. However, specific structural and functional details disclosed herein are merely representative for purposes of describing example embodiments. Example embodiments may, however, be embodied in many alternate forms and should not be construed as limited to only the example embodiments set forth herein.

FIG. 1is a side view of an e-vaping device according to at least one example embodiment.

In at least one example embodiment, as shown inFIG. 1, an electronic vaping device (e-vaping device)60may include a replaceable cartridge (or first section)70and a reusable battery section (or second section)72, which may be coupled together at a threaded connector205. It should be appreciated that the connector205may be any type of connector, such as a snug-fit, detent, clamp, bayonet, and/or clasp.

In at least one example embodiment, the connector205may be the connector described in U.S. application Ser. No. 15/154,439, filed May 13, 2016, the entire contents of which is incorporated herein by reference thereto. As described in U.S. application Ser. No. 15/154,439, the connector205may be formed by a deep drawn process.

In at least one example embodiment, the first section70may include a housing6and the second section72may include a second housing6′. The e-vaping device60includes a mouth-end insert8.

In at least one example embodiment, the housing6and the second housing6′ may have a generally cylindrical cross-section. In other example embodiments, the housings6and6′ may have a generally triangular cross-section along one or more of the first section70and the second section72. Furthermore, the housings6and6′ may have the same or different cross-section shape, or the same or different size. As discussed herein, the housings6and6′ may also be referred to as outer or main housings.

In at least one example embodiment, the e-vaping device60may include a conductive contact assembly300including a first contact310(shown inFIGS. 2-3 and 5-6), a second contact320, and an end cap housing340, which are described in more detail below. Each of the first contact310and the second contact320may be used in charging the power supply of the e-vaping device. The first contact310, the second contact320, and the end cap housing340are described in more detail below.

As discussed in more detail later, the first contact310and/or the second contact320may be utilized in charging the power supply of the e-vaping device as well as for inputting touch commands. Accordingly, the conductive contact assembly300may be configured to be used to charge the power supply of the e-vaping device and to input touch commands to control the e-vaping device.

FIG. 2is a cross-sectional view along line II-II of the e-vaping device ofFIG. 1.

In at least one example embodiment, as shown inFIG. 2, the first section70may include a reservoir22configured to store a pre-vapor formulation and a heater14that may vaporize the pre-vapor formulation, which may be drawn from the reservoir22by a wick28. The e-vaping device60may include the features set forth in U.S. Patent Application Publication No. 2013/0192623 to Tucker et al. filed Jan. 31, 2013, the entire contents of which is incorporated herein by reference thereto. In other example embodiments, the e-vaping device may include the features set forth in U.S. patent application Ser. No. 15/135,930 filed Apr. 22, 2016, U.S. patent application Ser. No. 15/135,923 filed Apr. 22, 2016, and/or U.S. Pat. No. 9,289,014 issued Mar. 22, 2016, the entire contents of each of which is incorporated herein by this reference thereto.

In at least one example embodiment, the pre-vapor formulation is a material or combination of materials that may be transformed into a vapor. For example, the pre-vapor formulation may be a liquid, solid and/or gel formulation including, but not limited to, water, beads, solvents, active ingredients, ethanol, plant extracts, natural or artificial flavors, and/or vapor formers such as glycerin and propylene glycol.

In at least one example embodiment, the first section70may include the housing6extending in a longitudinal direction and an inner tube (or chimney)62coaxially positioned within the housing6.

At an upstream end portion of the inner tube62, a nose portion61of a gasket (or seal)15may be fitted into the inner tube62; and an outer perimeter of the gasket15may provide a seal with an interior surface of the housing6. The gasket15may also include a central, longitudinal air passage20in fluid communication with the inner tube62to define an inner passage (also referred to as a central channel or central inner passage)21. A transverse channel33at a backside portion of the gasket15may intersect and communicate with the air passage20of the gasket15. This transverse channel33assures communication between the air passage20and a space35defined between the gasket15and a first connector piece37.

In at least one example embodiment, the first connector piece37may include a male threaded section for effecting the connection between the first section70and the second section72.

In at least one example embodiment, more than two air inlet ports44may be included in the housing6. Alternatively, a single air inlet port44may be included in the housing6. Such arrangement allows for placement of the air inlet ports44close to the connector205without occlusion by the presence of the first connector piece37. This arrangement may also reinforce the area of air inlet ports44to facilitate precise drilling of the air inlet ports44.

In at least one example embodiments, the air inlet ports44may be provided in the connector205instead of in the housing6. In other example embodiments, the connector205may not include threaded portions.

In at least one example embodiment, the at least one air inlet port44may be formed in the housing6, adjacent the connector205to minimize the chance of an adult vaper's fingers occluding one of the ports and to control the resistance-to-draw (RTD) during vaping. In at least one example embodiment, the air inlet ports44may be machined into the housing6with precision tooling such that their diameters are closely controlled and replicated from one e-vaping device60to the next during manufacture.

In at least one example embodiment, the air inlet ports44may be sized and configured such that the e-vaping device60has a resistance-to-draw (RTD) in the range of from about 60 mm H2O to about 150 mm H2O.

In at least one example embodiment, a nose portion93of a second gasket10may be fitted into a first end portion81of the inner tube62. An outer perimeter of the second gasket10may provide a substantially tight seal with an interior surface97of the housing6. The second gasket10may include a central channel63disposed between the inner passage21of the inner tube62and the interior of the mouth-end insert8, which may transport the vapor from the inner passage21to the mouth-end insert8. The mouth-end insert8includes at least two outlets, which may be located off-axis from the longitudinal axis of the e-vaping device60. The outlets may be angled outwardly in relation to the longitudinal axis of the e-vaping device60. The outlets may be substantially uniformly distributed about the perimeter of the mouth-end insert8so as to substantially uniformly distribute vapor in an adult vaper's mouth during vaping and create a greater perception of fullness in the mouth. Thus, as the vapor passes into the adult vaper's mouth, the vapor may enter the mouth and may move in different directions so as to provide a full mouth feel.

In at least one example embodiment, the space defined between the gaskets10and15and the housing6and the inner tube62may establish the confines of a reservoir22. The reservoir22may contain a pre-vapor formulation, and optionally a storage medium (not shown) configured to store the pre-vapor formulation therein. The storage medium may include a winding of cotton gauze or other fibrous material about the inner tube62.

In at least one example embodiment, the reservoir22may be contained in an outer annulus between the inner tube62and the housing6and between the gaskets10and15. Thus, the reservoir22may at least partially surround the inner passage21. The heater14may extend transversely across the inner passage21between opposing portions of the reservoir22. In some example embodiments, the heater14may extend parallel to a longitudinal axis of the inner passage21.

In at least one example embodiment, the reservoir22may be sized and configured to hold enough pre-vapor formulation such that the e-vaping device60may be configured for vaping for at least about 200 seconds. Moreover, the e-vaping device60may be configured to allow each puff to last a maximum of about 5 seconds.

In at least one example embodiment, the storage medium may be a fibrous material including at least one of cotton, polyethylene, polyester, rayon and combinations thereof. The fibers may have a diameter ranging in size from about 6 microns to about 15 microns (e.g., about 8 microns to about 12 microns or about 9 microns to about 11 microns). The storage medium may be a sintered, porous or foamed material. Also, the fibers may be sized to be irrespirable and may have a cross-section which has a Y-shape, cross shape, clover shape or any other suitable shape. In at least one example embodiment, the reservoir22may include a filled tank lacking any storage medium and containing only pre-vapor formulation.

During vaping, pre-vapor formulation may be transferred from the reservoir22and/or storage medium to the proximity of the heater14via capillary action of the wick28. The wick28may include at least a first end portion and a second end portion, which may extend into opposite sides of the reservoir22. The heater14may at least partially surround a central portion of the wick28such that when the heater14is activated, the pre-vapor formulation in the central portion of the wick28may be vaporized by the heater14to form a vapor.

In at least one example embodiment, the wick28may include filaments (or threads) having a capacity to draw the pre-vapor formulation. For example, the wick28may be a bundle of glass (or ceramic) filaments, a bundle including a group of windings of glass filaments, etc., all of which arrangements may be capable of drawing pre-vapor formulation via capillary action by interstitial spacings between the filaments. The filaments may be generally aligned in a direction perpendicular (transverse) to the longitudinal direction of the e-vaping device60. In at least one example embodiment, the wick28may include one to eight filament strands, each strand comprising a plurality of glass filaments twisted together. The end portions of the wick28may be flexible and foldable into the confines of the reservoir22. The filaments may have a cross-section that is generally cross-shaped, clover-shaped, Y-shaped, or in any other suitable shape.

In at least one example embodiment, the wick28may include any suitable material or combination of materials. Examples of suitable materials may be, but not limited to, glass, ceramic- or graphite-based materials. The wick28may have any suitable capillarity drawing action to accommodate pre-vapor formulations having different physical properties such as density, viscosity, surface tension and vapor pressure. The wick28may be non-conductive.

In at least one example embodiment, the heater14may include a wire coil which at least partially surrounds the wick28. The wire may be a metal wire and/or the heater coil may extend fully or partially along the length of the wick28. The heater coil may further extend fully or partially around the circumference of the wick28. In some example embodiments, the heater14may or may not be in contact with the wick28.

In at least one example embodiment, the heater coil may be formed of any suitable electrically resistive materials. Examples of suitable electrically resistive materials may include, but not limited to, copper, titanium, zirconium, tantalum and metals from the platinum group. Examples of suitable metal alloys include, but not limited to, stainless steel, nickel, cobalt, chromium, aluminum-titanium-zirconium, hafnium, niobium, molybdenum, tantalum, tungsten, tin, gallium, manganese and iron-containing alloys, and super-alloys based on nickel, iron, cobalt, stainless steel. For example, the heater14may be formed of nickel aluminide, a material with a layer of alumina on the surface, iron aluminide and other composite materials, the electrically resistive material may optionally be embedded in, encapsulated or coated with an insulating material or vice-versa, depending on the kinetics of energy transfer and the external physicochemical properties required. The heater14may include at least one material selected from the group consisting of stainless steel, copper, copper alloys, nickel-chromium alloys, super alloys and combinations thereof. In an example embodiment, the heater14may be formed of nickel-chromium alloys or iron-chromium alloys. In another example embodiment, the heater14may be a ceramic heater having an electrically resistive layer on an outside surface thereof.

The inner tube62may include a pair of opposing slots, such that the wick28and the first and second electrical leads109and109′ or ends of the heater14may extend out from the respective opposing slots. The provision of the opposing slots in the inner tube62may facilitate placement of the heater14and wick28into position within the inner tube62without impacting edges of the slots and the coiled section of the heater14. Accordingly, edges of the slots may not be allowed to impact and alter the coil spacing of the heater14, which would otherwise create potential sources of hotspots. In at least one example embodiment, the inner tube62may have a diameter of about 4 mm and each of the opposing slots may have major and minor dimensions of about 2 mm by about 4 mm.

The first lead109is physically and electrically connected to the male threaded connector piece37. As shown, the male threaded first connector piece37is a hollow cylinder with male threads on a portion of the outer later surface. The connector piece is conductive, and may be formed or coated with a conductive material. The second lead109′ is physically and electrically connected to a first conductive post110. The first conductive post110may be formed of a conductive material (e.g., stainless steel, copper, etc.), and may have a T-shaped cross-section as shown inFIG. 2. The first conductive post110nests within the hollow portion of the first connector piece37, and is electrically insulated from the first connector piece37by an insulating shell111. The first conductive post110may be hollow as shown, and the hollow portion may be in fluid communication with the air passage20. Accordingly, the first connector piece37and the first conductive post110form respective external electrical connection to the heater14.

In at least one example embodiment, the heater14may heat pre-vapor formulation in the wick28by thermal conduction. Alternatively, heat from the heater14may be conducted to the pre-vapor formulation by means of a heat conductive element or the heater14may transfer heat to the incoming ambient air that is drawn through the e-vaping device60during vaping, which in turn heats the pre-vapor formulation by convection.

It should be appreciated that, instead of using a wick28, the heater14may include a porous material which incorporates a resistance heater formed of a material having a high electrical resistance capable of generating heat quickly.

As shown inFIG. 2, the second section72includes a power supply1, a control circuit200, sensor16, and conductive contact assembly (also referred to as a contact assembly or connector assembly)300. As shown, the control circuit200and sensor16are disposed in the housing6′. The contact assembly300forms one end of the second section72, and a female threaded second connector piece112forms a second end. As shown, the second connector piece112has a hollow cylinder shape with threading on an inner later surface. The inner diameter of the second connector piece112matches that of the outer diameter of the first connector pieces37such that the two connector pieces37and112may be threaded together to form a connection205. Furthermore, the second connector piece112, or at least the other later surface is conductive, for example, formed of or including a conductive material. As such, an electrical and physical connection occurs between the first and second connector pieces37and112when connected.

As shown, a first lead720electrically connects the second connector piece112to the control circuit200. A second lead730electrically connects the control circuit200to a first terminal113of the power supply1. A third lead725electrically connects a second terminal114of the power supply1to the power terminal of the control circuit200to provide power to the control circuit200. The second terminal114of the power supply1is also physically and electrically connected to a second conductive post115. The second conductive post115may be formed of a conductive material (e.g., stainless steel, copper, etc.), and may have a T-shaped cross-section as shown inFIG. 2. The second conductive post115nests within the hollow portion of the second connector piece112, and is electrically insulated from the second connector piece112by an insulating shell116. The second conductive post115may also be hollow as shown. When the first and second connector pieces37and112are mated, the second conductive post115physically and electrically connects to the first conductive post110. Also, the hollow portion of the second conductive post115may be in fluid communication with the hollow portion of the first conductive post110.

While the first section70has been shown and described as having the male connector piece and the second section72has been shown and described as having the female connector piece, an alternative embodiment includes the opposite where the first section70has the female connector piece and the second section72has the male connector piece.

In at least one example embodiment, the power supply1includes a battery arranged in the e-vaping device60. The power supply1may be a Lithium-ion battery or one of its variants, for example a Lithium-ion polymer battery. Alternatively, the power supply1may be a nickel-metal hydride battery, a nickel cadmium battery, a lithium-manganese battery, a lithium-cobalt battery or a fuel cell. The e-vaping device60may be vapable by an adult vaper until the energy in the power supply1is depleted or in the case of lithium polymer battery, a minimum voltage cut-off level is achieved.

In at least one example embodiment, the power supply1is rechargeable. The second section72may include circuitry configured to allow the battery to be chargeable by an external charging device. To recharge the e-vaping device60, an USB charger or other suitable charger assembly may be used as described below.

In at least one example embodiment, the sensor16is configured to generate an output indicative of a magnitude and direction of airflow in the e-vaping device60. The control circuit200receives the output of the sensor16, and determines if (1) the direction of the airflow indicates a draw on the mouth-end insert8(versus blowing) and (2) the magnitude of the draw exceeds a threshold level. If these vaping conditions are met, the control circuit200electrically connects the power supply1to the heater14; thus, activating the heater14. Namely, the control circuit200electrically connects the first and second leads720and730(e.g., by activating a heater power control circuit945as discussed below with regard toFIG. 6) such that the heater14becomes electrically connected to the battery1. In an alternative embodiment, the sensor16may indicate a pressure drop, and the control circuit200activates the heater14in response thereto.

In at least one example embodiment, the control circuit200may also include a light48, which the control circuit200activates to glow when the heater14is activated and/or the battery is recharged. The light48may include one or more light-emitting diodes (LEDs). The LEDs may include one or more colors (e.g., white, yellow, red, green, blue, etc.). Moreover, the light48may be arranged to be visible to an adult vaper during vaping, and may be positioned between a first end210and a second end220of the e-vaping device60. In addition, the light48may be utilized for e-vaping system diagnostics or to indicate that recharging is in progress. The light48may also be configured such that the adult vaper may activate and/or deactivate the heater activation light48for privacy.

In at least one example embodiment, the control circuit200may include a time-period limiter. In another example embodiment, the control circuit200may include a manually operable switch for an adult vaper to initiate heating. The time-period of the electric current supply to the heater14may be set or pre-set depending on the amount of pre-vapor formulation desired to be vaporized. In yet another example embodiment, the sensor16may detect a pressure drop and the control circuit200may supply power to the heater14as long as heater activation conditions are met.

Next, operation of the e-vaping device to create a vapor will be described. For example, air is drawn primarily into the first section70through the at least one air inlet44in response to a draw on the mouth-end insert8. The air passes through the air inlet50, into the transverse channel33at the backside portion of the gasket15and into the air passage20of the gasket15, into the inner passage21, and through the outlet24of the mouth-end insert8. If the control circuit200detects the vaping conditions discussed above, the control circuit200initiates power supply to the heater14, such that the heater14heats pre-vapor formulation in the wick28to form a vapor. The vapor and air flowing through the inner passage21combine and exit the e-vaping device60via the outlet24of the mouth-end insert8.

When activated, the heater14may heat a portion of the wick28surrounded by the heater for less than about 10 seconds.

In at least one example embodiment, the first section70may be replaceable. In other words, once the pre-vapor formulation of the cartridge is depleted, only the first section70may be replaced. An alternate arrangement may include an example embodiment where the entire e-vaping device60may be disposed once the reservoir22is depleted. In at least one example embodiment, the e-vaping device60may be a one-piece e-vaping device.

In at least one example embodiment, the e-vaping device60may be about 80 mm to about 110 mm long and about 7 mm to about 8 mm in diameter. For example, in one example embodiment, the e-vaping device may be about 84 mm long and may have a diameter of about 7.8 mm.

In at least one example embodiment, as shown inFIG. 2, the e-vaping device60includes the contact assembly300as described in greater detail below with reference toFIGS. 4-5.

FIG. 3Ais an enlarged view of an end of the second (or battery) section of an e-vaping device according to at least one example embodiment.

In at least one example embodiment, as shown inFIG. 3A, the second section72is the same as inFIG. 2. The control circuit200is disposed on a rigid printed circuit board410. The circuit board410is connected to the first contact310via lead700. The circuit board410is connected to the second contact320via lead710.

FIG. 3Bis an enlarged view of an end of the second section of an e-vaping device according to at least one example embodiment.

In at least one example embodiment, as shown inFIG. 3B, the second section72is the same as inFIG. 2. The control circuit200is disposed on a flexible printed circuit board1000. The flexible printed circuit board1000allows for the inclusion of a larger battery1since the flexible printed circuit board1000requires less space within the housing6′ than the rigid circuit board410ofFIG. 3A.

FIG. 4is an exploded view of the conductive contact assembly ofFIG. 2according to at least one example embodiment.FIG. 5is a cross-sectional view of an assembled (or non-exploded) version of the conductive contact assembly ofFIG. 4along line V-V ofFIG. 4according to at least one example embodiment.

As shown inFIGS. 4 and 5, the contact assembly300is the same as shown inFIG. 2, and is shown in greater detail. As shown inFIG. 4, the contact assembly300includes the first contact310, the second contact320, and the end cap housing340.

The first contact310has a disk shape. In at least one example embodiment, the first contact310may be formed of a printed circuit board (PCB), which may be rigid or flexible. The first contact310includes a substrate315with a first conductive portion312formed on an upper surface thereof and a second conductive portion314formed on a bottom surface thereof. At least one conductive via313electrically connects the first and second conductive portions312and314(seeFIG. 5). The first conductive portion312and the second conductive portion314may be copper, stainless steel, magnetic stainless steel, etc. The first conductive portion312may have a generally circular shape, and/or form a pattern. For example, the conductive portion312forms the outline of the number “10” in the example ofFIG. 4. The first conductive portion312has an area such that the second contact320does not overlap the first conductive portion312, and the first conductive portion312of the first contact310is electrically insulated from the second contact320. Instead, a non-conductive portion311of the substrate315is exposed, and the second contact320overlaps and/or contacts the non-conductive portion311.

As shown, the end cap housing340has a generally, hollow cylindrical shape defined by a sidewall350. A lower portion of the sidewall350includes ridges355, and an upper portion includes a flange360. In at least one example embodiment, the flange360has an outer diameter that is about the same as the outer diameter of the housing6′. The sidewall350has an outer diameter that is slightly less than an inner diameter of the housing6′ so that the sidewall350may be held in place in the housing6′ by friction fit. The sidewall350may include the ridges355to aid in holding the end cap housing340within the housing6′.

In at least one example embodiment, the end cap housing340includes a ridge or inner ledge305projecting from the inner later surface. The first contact310rests on the inner ledge305. Two projecting fins315project from an end of the end cap housing340. The projecting fins315separate the inner ledge305from the flange360. The second contact320rests on an outer ledge of the flange360. While two projecting fins315, each extending at least 90 degrees around the end of the end cap housing340are shown, it will be understood the more or less than two projecting fins315may be formed.

As stated above, a portion of the second contact320mates with the flange360of the end cap housing340, and in doing so, tabs380of the second contact320fit in slots390in the sidewall350of the end cap housing340so as to secure the second contact320with the end cap housing340, and hold the first contact310in place against the inner ledge305. As shown inFIG. 5, the lead700is connected to the second conductive portion314and the lead710is connected to at least one of the tabs380.

In at least one example embodiment, the end cap housing340may be formed of plastic. At least a portion of the flange360of the end cap housing340may be transparent so that light from the heater activation light48may be seen through the flange360. The first contact310and the second contact320may be opaque (e.g., may include a solder mask to substantially prevent light from being seen through the PCB), such that the light48may not be seen through the end of the e-vaping device60.

As shown inFIG. 4, stops440are disposed on the tabs380, and the stops latch beneath a portion450of the flange360when the tabs380are mated with the slots390. The tabs380may be resilient such that the tabs380bend slightly when being inserted into the slots390, but spring back into an original position to lock the tabs380within the slots390.

The second contact320is conductive, and conductive portions of the first contact310are electrically isolated from the second contact320as described above. Also, in at least one example embodiment, the first contact310and the second contact320are magnetic. Accordingly, the tabs380and the slots390are configured to lock together so as to prevent magnetic attraction from removing the first contact310and the second contact320from the e-vaping device60.

In at least one alternative embodiment, at least a portion of the first contact310may be substantially transparent such that the light48shines through a side portion of the end cap housing340.

FIG. 6is a circuit diagram illustrating an example embodiment of the control circuit200of the e-vaping device shown inFIG. 1. The control circuit200shown inFIG. 6is described with regard to a situation in which the first section70is connected to the second section72as discussed above. Thus, both the heater14and the power supply1are shown inFIG. 6.

As shown inFIG. 6, the control circuit200includes a microcontroller905, a charge controller800, a mode control switch circuit920, a heater power control circuit945, a resistance measurement circuit94and a resistor910. In this example, the mode control switch circuit920includes a mode control switch U3, and the heater power control circuit945includes a heater power control switch U1. The microcontroller905includes an analog-to-digital converter (ADC)9052and a digital-to-analog converter (DAC)9054. The ADC9052may be a 10-bit ADC and the DAC9054may be an 8-bit DAC. However, example embodiments should not be limited to these examples.

The resistance measurement circuit94includes a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, an operational amplifier (OP-AMP)947and a resistance measurement switch circuit946. The resistance measurement switch circuit946includes a resistance measurement switch U2. The OP-AMP947may be a differential operational amplifier.

Each of the heater power control switch U1, the resistance measurement switch U2and the mode control switch U3may be transistors (e.g., NMOS or MOSFET transistors), although example embodiments should not be limited to these examples. For example purposes, the switches U1through U3will be described herein as transistors. In this regard, the heater power control switch U1may be referred to as a heater power control transistor U1, the resistance measurement switch U2may be referred to as a resistance measurement transistor U2, and the mode control switch U3may be referred to as mode control transistor U3. Again, however, example embodiments should not be limited to these examples.

Referring toFIG. 6, a capacitive input940of the microcontroller905is connected to a first terminal of the resistor910. A second terminal of the resistor910is connected to the second contact320via the lead710.

A first terminal of the mode control transistor U3is connected to a first node NODE1between the second terminal of the resistor910and the second contact320. A second terminal of the mode control switch U3is connected to the negative terminal of the power supply1, a first end of the heater14and a first terminal of the fifth resistor R4of the resistance measurement circuit94at second node NODE2. A gate of the mode control transistor U3is connected to a touch/charge enable terminal930(also referred to herein as an enable terminal) at the microcontroller905. As discussed herein, the negative terminal of the power supply1may also be referred to as common ground, ground, ground plane or common ground plane.

The charge controller800is electrically connected between the first contact310(via the lead700) and the charge enable terminal935of the microcontroller905. The charge controller800is also electrically connected to the positive terminal of the power supply1at a third node NODE3. The positive terminal of the power supply1is connected to the control circuit200via lead703, and also connected to the power input terminal PWR of the microcontroller905via the lead725to provide power to the control circuit200and the microcontroller905.

According to at least one example embodiment, the charge controller800may be any known charge controller. In one example, the charge controller800may include a linear regulator. According to at least one example embodiment, the charge controller800may be configured to determine a level of charge of the power supply1, and to control application of charging current iCHand/or voltage to the power supply1based on the determined level of charge. The charge controller800may also detect input of a charging current iCHvia the first contact310and the lead700, and output a charge enable signal CHG_EN based on the detected charging current iCH. In at least one example embodiment, the charge enable signal CHG_EN may be disabled (e.g., have a first logic value, such as a logic low) when no charging current is detected, and may be enabled (e.g., have a second logic value, such as a logic high level) when the charging current is detected. In another example, the charge enable signal CHG_EN may be described as being output when the charging current is detected, and not output when no charging current is detected. The charge controller800may also output regulated charging current iCHto the positive terminal of the power supply1to charge the power supply1. Because charge controllers such as this are well-known, a more detailed discussion is omitted.

Still referring toFIG. 6, a first terminal of the heater power control transistor U1is connected to the positive terminal of the power supply1and a second terminal of the heater power control transistor U1is connected to a second end of the heater14at a fourth node NODE4via the first lead720between the heater14and the control circuit200. A gate of the heater power control transistor U1is electrically connected to a heater power control terminal955of the microcontroller905. According to at least this example embodiment, the microcontroller905outputs a heater power control signal HEAT_PWR_CTRL to control the heater power control transistor U1to regulate and control power from the power supply1to the heater14.

The resistance measurement circuit94is electrically connected to the first terminal of the heater power control transistor U1, the positive terminal of the power supply1and the charge controller800at a fifth node NODE5, via node NODE3. The resistance measurement circuit94is also electrically connected to the ADC9052, the DAC9054and a resistance measurement enable terminal956at the microcontroller905.

Within the resistance measurement circuit94, a first terminal of the resistance measurement transistor946is connected to the first terminal of the heater power control transistor U1, the positive terminal of the power supply1and the charge controller800at the fifth node NODE5. A second terminal of the resistance measurement transistor946is connected to a first terminal of first resistor R1. The gate of the resistance measurement transistor946is connected to the resistance measurement enable terminal956at the microcontroller905.

The second terminal of the first resistor R1is connected to a positive input of the operational amplifier (OP-AMP)947, the second terminal of the heater power control transistor U1, the second end of the heater14and an analog input ANALOG of the microcontroller905at a sixth node NODE6.

The output terminal of the OP-AMP947is connected to the ADC9052at the microcontroller905. The second resistor R2is connected in parallel between the negative input terminal and the output terminal of the OP-AMP947. The negative input terminal of the OP-AMP947is also connected to a first terminal of the third resistor R3and a second terminal of the fourth resistor R4.

The second terminal of the third resistor R3is connected to the DAC9054at the microcontroller905.

Still referring toFIG. 6, the microcontroller905is also electrically connected to the sensor16.

Although the example embodiment shown inFIG. 6is discussed with regard the resistance measurement circuit94being separate from the microcontroller905, example embodiments should not be limited to this example. Rather, according to one or more other example embodiments, the resistance measurement circuit94, or one or more components thereof (e.g., the OP-AMP947), may be included and implemented in the microcontroller905.

Example operation of the control circuit200shown inFIG. 6will now be described.

According to at least one example embodiment, when the first section70is connected to the second section72, the mode control transistor U3is initially set to the ON state. In this example, the mode control transistor U3transitions from the ON state to the OFF state periodically based on a monitoring frequency for the control circuit200in response to switching of a charge monitoring signal EN_SIG from the microcontroller905via the enable terminal930(also referred to herein as an enable terminal). The monitoring frequency is discussed in more detail later.

According to at least some example embodiments, each time the mode control transistor U3transitions from the ON state to the OFF state the control circuit200monitors for a touch event for a relatively short interval (sometimes referred to as a touch detection interval). This relatively short interval may occur at the beginning of what may be referred to as a “wake” cycle based on the sleep state of the microcontroller, after which the control circuit200may return to a state in which charging of power supply1may be initiated.

As discussed herein, switching of the charge monitoring signal EN_SIG may refer to transitioning of the signal from the logic high to the logic low level. As discussed herein, switching of the charge monitoring signal EN_SIG to the logic low level may also be referred to as disabling or disabling output of the charge monitoring signal EN_SIG. However, example embodiments should not be limited to this example.

As discussed herein, the ON state of the mode control transistor920may also be referred to as an active state, or as the mode control transistor920being activated. Similarly, the OFF state may also be referred to as an inactive state or as the mode control transistor920being deactivated.

According to one or more example embodiments, the microcontroller905and/or the control circuit200may operate in one of a monitoring mode, a touch command mode and a charging mode. Example operation of the control circuit200in each of these operating modes will be discussed in more detail below.

In the monitoring mode, the charging enable signal CHG_EN is disabled, and the mode control transistor U3is periodically deactivated in response to disabling of the charge monitoring signal EN_SIG from the enable terminal930of the microcontroller905. Disabling of the charge monitoring signal EN_SIG may also be characterized as enabling a touch monitoring signal.

The frequency of the charge monitoring signal EN_SIG, and consequently the periodicity of the deactivation of the mode control transistor U3, is based on a state of the microcontroller905in the monitoring mode. In one example, the monitoring mode may include a plurality of states. In each of the plurality of states, the charge monitoring signal EN_SIG may have a different frequency, and thus, the deactivation of the mode control transistor U3may have a different periodicity. In one example, the monitoring mode may include an active state, a standby state and a hibernate state.

In an example of the active state, the charge monitoring signal EN_SIG may have a frequency of about 100 Hz, such that the mode control transistor U3is deactivated (transitions to the OFF state) about every 0.01 seconds.

In an example of the standby state, the charge monitoring signal EN_SIG may have a frequency of about 50 Hz, such that the mode control transistor U3is deactivated about every 0.05 seconds.

In an example of the hibernate state, the charge monitoring signal EN_SIG may have a frequency of about 10 Hz such that the mode control transistor U3is deactivated about every 0.10 seconds.

When a cartridge including a heater element (e.g., first section70) is attached to the battery section (e.g., second section72), the microcontroller905detects that the cartridge is attached to the battery section and defaults to the active state. As is generally well-known, the microcontroller905may detect attachment of a cartridge to the battery section based on a change in resistance (e.g., from essentially infinite resistance to a finite resistance value) resulting from attachment of the cartridge.

If a cartridge is attached and no puff event is detected by the sensor16within a first threshold interval (e.g., about 20 seconds) from the time the cartridge was attached, then the microcontroller905transitions to the standby state. While in the standby state, if no puff event is detected by the sensor16within a second threshold time period (e.g., 40 seconds) from attachment of the cartridge (or, alternatively, another interval of 20 seconds from the time at which the microcontroller905transitioned to the standby state), then the microcontroller905transitions to the hibernate state. The microcontroller stays in the hibernate state until a puff event is detected by the sensor16. If the sensor16detects a puff event in the standby or hibernate states, the microcontroller905transitions to the active state to increase responsiveness to an adult vaper. When no cartridge is attached, the microcontroller905remains in the hibernate state until a cartridge is attached. As discussed above, when the cartridge is attached, the microcontroller905transitions to the active state.

FIG. 14is a flow chart illustrating an example embodiment of a method of operating the control circuit200shown inFIG. 6. The example embodiment shown inFIG. 14will be discussed with regard to the microcontroller905initially operating in the monitoring mode with the mode control transistor920in the ON state. However, example embodiments should not be limited to this example.

As discussed above, in the monitoring mode, the mode control transistor U3is periodically deactivated by disabling the charge monitoring signal EN_SIG output from the enable terminal930of the microcontroller905. The method shown inFIG. 14may be performed periodically when the mode control transistor920is deactivated. In this regard, the method shown inFIG. 14may be performed according to the frequency of the charge monitoring signal EN_SIG.

Referring toFIG. 14, when the mode control transistor U3is deactivated in response to the disabling of the charge monitoring signal EN_SIG by the microcontroller905, at step S1404the microcontroller905detects whether a touch has been input by an adult vaper.

With regard to step S1404, in one example, when the mode control transistor U3is in the OFF state, and the adult vaper touches the second contact320, the part of the adult vaper (e.g., the finger) touching the second contact320and the second contact320itself act as terminals of a capacitor, which changes the measured capacitance along the circuit path between the second contact320and the capacitive input940. When the microcontroller905detects this change in capacitance, the microcontroller905determines that the adult vaper has touched the second contact320, thereby detecting a touch input by the adult vaper.

If the microcontroller905does not detect a touch input by an adult vaper at step S1404, then the microcontroller905remains in the monitoring mode and operates as discussed above.

Still referring to step S1404, if the microcontroller905detects a touch input, then the microcontroller905enters the touch command mode at step S1406.

In the touch command mode, the mode control transistor920is maintained in the OFF state to electrically isolate the contact320, lead710and resistor910from at least the heater14and the negative terminal of the power supply1. Since the default state of the mode control transistor U3is ON, the microcontroller905maintains the mode control transistor U3in the OFF state by preventing the charge monitoring signal EN_SIG from being enabled (or from being output) and turning on the mode control transistor920.

Still referring toFIG. 14, after entering the touch command mode at step S1406, the microcontroller905detects a touch command input by the adult vaper at step S1408. According to at least some example embodiments, the microcontroller905detects the touch command input by the adult vaper based on the frequency and/or length of the touch by the adult vaper.

Once having detected the touch command input by the adult vaper at step S1408, the microcontroller905executes the detected touch command at step S1410.

The following tables illustrate example touch commands and operations executed in response to said touch inputs according to one or more example embodiments.

TABLE 1Battery Level On-Demand IndicationInput = Single Tap on Contact AssemblyBattery Charge Level (%)Device Response100-20Display Solid White/Green LED for 5seconds20-10Display Solid Yellow LED for 5 seconds10-0Display Solid Red LED for 5 seconds0Blink Solid Red LED 5 times (0.5 secondson and 0.5 second off)

TABLE 2Display while Vaping (Option 1)Input = Draw on DeviceBattery Charge Level (%)Device Response100-20Display Solid White/Green LED during puff20-10Display Solid Yellow LED during puff10-0Display Solid Red LED during puff0Blink Solid Red LED 5 times (0.5 secondson and 0.5 second off)

TABLE 4LED Off Input = Press and Hold ContactAssembly for 5 secondsBattery Charge Level (%)Device Response100-0none

In at least one example embodiment, as shown in Tables 1-4, the e-vaping device may respond to a variety of different touch commands. In other example embodiments, the vaping profile may be altered by inputs or the device may be locked from vaping by tapping the contact assembly.

Still referring toFIG. 14, although not shown explicitly, after executing the detected touch command, the microcontroller905may return to the monitoring mode.

FIG. 15is a flow chart illustrating another example embodiment of a method of operating the control circuit200shown inFIG. 6. The example embodiment shown inFIG. 15will also be discussed with regard to the microcontroller905initially operating in the monitoring mode with the mode control transistor U3in the ON state. However, example embodiments should not be limited to this example.

When the mode control transistor920is in the ON state, at step S1504the microcontroller905determines whether the power supply1is being charged based on the charging enable signal CHG_EN from the charge controller800. As mentioned above, the charge controller800outputs the charging enable signal CHG_EN based on the presence of the charging current iCHthrough the first contact310and the lead700. In one example, the microcontroller905determines that the power supply1is being charged if the charge enable signal CHG_EN from the charge controller800is enabled (e.g., has logic high level). As discussed herein, the enabling of the charge enable signal CHG_EN may also be referred to as output of the charge enable signal CHG_EN.

If the microcontroller905detects that the power supply1is charging at step S1504, then the microcontroller905enters the charging mode at step S1508.

In the charging mode, the mode control transistor920remains in the ON state until the charge controller800indicates that the charging current iCHis no longer flowing to the positive terminal of the power supply1by disabling the charge enable signal CHG_EN. In one example, while in the charging mode, the microcontroller905maintains the mode control transistor920in the ON state by preventing disabling of the enabled charge monitoring signal EN_SIG.

Although not explicitly shown inFIG. 15, when the charge controller800disables the charge enable signal CHG_EN, the microcontroller905may return to the monitoring mode.

Returning to step S1504, if the microcontroller905does not detect that the power supply1is charging, then the microcontroller905remains in the monitoring mode and operates as discussed above.

As discussed above, the control circuit200further includes a resistance measurement circuit94.

During puff events by an adult vaper, the application of power to the heater14changes the resistance of the heater14. Using the resistance measurement circuit94, the microcontroller905is configured to monitor resistance changes in the heater14during puff events, and to control power to the heater14based on the changes in resistance. In at least one example embodiment, the microcontroller905may selectively disable vaping operation by cutting power to the heater14based on changes in resistance of the heater14.

In the resistance measurement circuit94shown inFIG. 6, the first resistor R1is a precise reference resistor with known resistance value (e.g., about 10.00Ω). The resistors R2, R3and R4are stable resistors used to set the gain and bias of the OP-AMP947. The resistors R2, R3, and R4also have known resistance values. The DAC9054and the ADC9052share the same reference voltage Vbattery. In this case, the reference voltage Vbatteryis the voltage of the power supply1. Given the configuration of the resistance measurement circuit94shown inFIG. 6, the voltage output Vop-ampof the OP-AMP947is given by Equation (1) shown below.

According to one or more example embodiments, the resistance measurement circuit94may operate in a calibration mode or phase and a monitoring mode or phase.

FIG. 16is a flow chart illustrating an example embodiment of a method of operating the control circuit200in the calibration phase. As discussed above, when a cartridge including a heater element (e.g., first section70) is attached to the battery section (e.g., second section72), the microcontroller905defaults to the active state. Additionally, when the cartridge including a heater element (e.g., first section70) is attached to the battery section (e.g., second section72), the control circuit200enters the calibration phase. The calibration phase is also referred to as the fine resistance calibration phase.

The stress on the heater14during a puff event may cause a shift in the “at-rest” resistance of the heater coil. In one example, during the first 5 to 10 puff events on a new cartridge, the “at-rest” resistance may change as much as 0.5% from a previous value. Accordingly, the microcontroller905may monitor the length of time between puff events, and if the time interval between puff events exceeds a threshold value (e.g., about 25 seconds), the control circuit200may also enter the calibration phase. Accordingly, the control circuit200may enter the calibration phase in response to at least two trigger events; that is, attachment of a new cartridge to the second section72, and if the time interval between puff events exceeds a threshold value.

Referring toFIG. 16, in response to one or more of the above-mentioned trigger events, at step S1604the microcontroller905measures the coarse resistance of the heater coil Rcoil_coarse. In this case, the coarse resistance of the heater coil is a low resolution measurement by the microcontroller905in the analog domain.

According to at least one example embodiment, the arrangement of heater14and the first resistor R1, which is a known stable resistance, in the resistance measurement circuit94presents a voltage at the sixth node NODE6, which is input to and/or sensed at the analog input ANALOG of the microcontroller905. In this example, the first resistor R1and the coil of the heater15create a voltage divider circuit. The microcontroller905then calculates the resistance of heater14based on the known voltage of the power supply (e.g., Vin), the sensed/measured voltage at the sixth node NODE6(e.g., Vout) and the known resistance of the first resistor R1.

According to at least one other example embodiment, the OP-AMP947may be a component integrated in microcontroller905. In this example, the coarse resistance measurement Rcoil_coarseis acquired by reconfiguring the positive input of OP-AMP947as an ADC input of microcontroller905. Once the pin is reconfigured, the arrangement of heater14and the first resistor R1, which is a known stable resistance, presents a voltage on NODE6based on which the microcontroller905may calculate the resistance of heater14. The microcontroller905may calculate the resistance of the heater14in the same manner as discussed above.

At step S1606, the microcontroller905selects an appropriate digital code or word CODEDACbased on the initial coarse resistance measurement Rcoil_coarse. According to at least one example embodiment, the microcontroller905selects the digital code CODEDACso that the output voltage Vop-ampof the OP-AMP947does not saturate the input of the ADC9052during subsequent measurements. In one example, the digital code CODEDACmay be selected such that the output of the OP-AMP947is substantially zero.

At step S1608, the ADC9052at the microcontroller905samples the voltage output Vop-ampof the OP-AMP947to generate a digital representation CODEADC_0of the voltage output Vop-ampof the OP-AMP947.

After calibration, or between iterations of the calibration phase, the digital code CODEDACis maintained to fix the voltage output of the DAC9054.

After detection of a puff event by the sensor16and during subsequent vaping, the heater power control signal HEAT_PWR_CTRL controls the heater power control transistor U1to regulate the voltage output from the power supply1to the heater14. According to at least one example embodiment, the heater power control signal HEAT_PWR_CTRL has a duty cycle of 64 ms. According to at least this example embodiment, the duty cycle includes a regulating period and a resistance measurement period. The regulating period may be one of the first and the last 60 milliseconds (ms) of the 64 ms, whereas the resistance measurement period may be the remaining portion of the duty cycle (e.g., one of the first and last 4 ms of the duty cycle).

During the regulating period of the duty cycle, the heater power control signal HEAT_PWR_CTRL is pulse train causing the heater power control transistor U1to switch on and off to regulate the voltage applied to the heater14by the power supply1. Also during the regulating period of the duty cycle, the resistance measurement enable signal RES_MEAS_EN is disabled such that resistance measurement transistor U2is maintained in the OFF (or open) state.

During the resistance measurement period, the heater power control transistor U1is switched to the OFF (open) state, while the resistance measurement transistor U2is maintained in the ON (closed) state for a given time interval sufficient to allow the microcontroller905to acquire a voltage sample from the output of the OP-AMP947. In one example, the given time interval may be less than or equal to about 4 ms (e.g., about 1 ms).

FIG. 17is a flow chart illustrating an example embodiment of a method of operating the control circuit200in the resistance measurement phase. The method shown inFIG. 17is performed during the resistance measurement period of the duty cycle during a puff event.

Referring toFIG. 17, in response to attaching a cartridge including a heater element (e.g., first section70) to the battery section (e.g., second section72), at step S1702the microcontroller905initiates a counter value i for the cartridge to zero. The microcontroller905utilizes the counter value i to track the number of (e.g., consecutive) times power to the heater14is cutoff for the attached cartridge.

After initializing the counter value i, when the sensor16detects a puff event at step S1704, the microcontroller905measures/samples the output voltage Vop-ampfrom the OP-AMP947at step S1706. The microcontroller905then generates an updated digital representation (CODEADC_1) of the output voltage Vop-ampof the OP-AMP947based on the sampled output voltage Vop-amp.

At step S1708, the microcontroller905then calculates the percentage change in resistance % ΔR between the initial measured resistance of the coil Rcoil_0and the current resistance Rcoil_1of the heater14based on the updated digital representation CODEADC_1of the output voltage Vop-ampof the OP-AMP947according to Equation (2) shown below.

After calculating the percentage change in resistance % ΔR, at step S1710the microcontroller905determines whether to cut power to the heater based on a comparison between the calculated percent change in resistance % ΔR and a threshold percentage change % RTH. If the calculated percentage change in resistance % ΔR exceeds (e.g., is greater than) the threshold percentage change % RTH, then at step S1711the microcontroller905cuts power to the heater14by disabling the heater power control signal HEAT_PWR_CTRL thereby setting the heater power control transistor U1to the OFF state (open).

The microcontroller905then increments the counter value i at step S1712, and determines whether the counter value i exceeds a counter threshold LOCK_TH at step S1714. The counter threshold LOCK_TH represents a threshold number of times the power to the heater14for the current cartridge may be temporarily cutoff before further vaping by the adult vaper using the current cartridge is prevented. The counter value i exceeds the counter threshold LOCK_TH if the counter value is greater than or equal to the counter threshold LOCK_TH. In one example, the counter threshold LOCK_TH may be about 5, but example embodiments should not be limited to this example.

If the microcontroller905determines that the counter value i exceeds the counter threshold LOCK_TH, then at step S1716the microcontroller905prevents power from reaching the heater14until the current cartridge is removed and replaced. As with step S1711, the microcontroller905cuts power to the heater14by disabling the heater power control signal HEAT_PWR_CTRL thereby setting the heater power control transistor U1to the OFF state (open).

Returning to step S1714, if the counter value i does not exceed the counter threshold LOCK_TH (i<LOCK_TH), then the process returns to step S1704and the method continues as discussed above upon detection of a next puff event by the sensor16.

Returning now to step S1710, if the microcontroller905determines % ΔR does not exceed the threshold percentage change % RTH(% ΔR<% RTH), and thus, power to the heater14need not be cutoff, then the microcontroller905re-initializes the counter value i to zero at step S1702, and continues as discussed above upon detection of a next puff event by the sensor16.

Although Equation (2) provides a complete analytic solution of the change in resistance, some assumptions may be made to simplify the equation. One assumption is that the resistance change is relatively small so that some intermediate steps may be linearized using Taylor expansion, thereby resulting in Equation (3) shown below.

Because of a potentially increased quiescent current draw, to use the capacitive touch channel on the microcontroller905, the control circuit200may detect an effect of an adult vaper's body on the resistance of the circuit in at least one example embodiment. Differences in skin moisture should not affect the ability of the circuit to respond to an adult vaper's input.

As discussed above, according to one or more example embodiments, the mode control transistor920may be a MOSFET or NMOS transistor and may provide more reliable detection even when sensitivity of the capacitance measurement is decreased.

In at least one other example embodiment, a diode (not shown) may be added to the charge controller input. In this example, the diode acts as an open circuit until a charge voltage is present across the second contact320and the first contact310.

FIG. 7is a diagram of a control circuit according to another example embodiment.

In at least one example embodiment, an adult vaper's commands may be detected through changes in resistance, rather than capacitance. In this example, the second contact320is the charge cathode, which is electrically connected to the negative terminal70of the power supply. The first contact310′ is the charge anode, which is electrically connected to an input of an analog-to-digital (ADC)1010included in the microcontroller905′.

According to at least this example embodiment, the microcontroller905′ may be configured to detect a resistance between the charge anode310′ and the charge cathode320′. When an adult vaper places, for example, a finger on the across the charge anode310′ and the charge cathode320′, the connection between the charge anode310′ and the charge cathode320′ is closed thereby changing the resistance of the input to the microcontroller905′. The microcontroller905′ detects this change in resistance to detect a touch input by the adult vaper.

The circuit ofFIG. 7may allow for a lower quiescent current draw. The resistive detection circuit may be configured as an interrupt to the microcontroller905′, which may allow for the microcontroller905′ and accessories to be in a low power sleep state until an adult vaper closes the circuit by touching the second contact320of the e-vaping device60, which wakes the e-vaping device60so that an appropriate response to the touch may be given.

FIG. 8is a diagram of a control circuit according to yet another example embodiment.

In at least one example embodiment, as shown inFIG. 8, the first contact310″ is a charge anode, which is electrically connected to a charge controller1120via a diode1140. The first contact310″ is also electrically connected to the capacitive input1110of the microcontroller905″ via a resistor1100. In this example, the control circuit enables both resistive touch detection and capacitive touch detection by the e-vaping device60.

According to at least this example embodiment, a more sensitive resistance measurement may be used to wake the e-vaping device60when an adult vaper touches the second contact320of the e-vaping device60. After measuring the resistance, capacitance is measured to verify that the adult vaper has touched the second contact320, and to suppress quiescent current draw requirements of circuits utilizing capacitive touch detection alone.

FIG. 9is a perspective view of a charger of an e-vaping device according to at least one example embodiment.

In at least one example embodiment, as shown inFIG. 9, the battery1of the e-vaping device60ofFIGS. 1-8may be recharged using a charger500.

In at least one example embodiment, the charger500includes a housing510including a top wall520. The top wall520may be rounded and/or generally bell-shaped or dome-shaped in cross-section, such that side portions of the top wall520are angled downward from a central portion of the top wall520. The housing510may also include a sidewall530connected to the top wall520. The top wall520, at least one sidewall530, and a bottom wall535(shown inFIG. 12) define an internal compartment that houses a charging circuit as discussed below. The housing510may be formed from one or more pieces of a material, such as a plastic or a metal.

In at least one example embodiment, the sidewall530has generally rounded corners, such that the sidewall530extends entirely about a perimeter of the charger500. In at least one example embodiment, the sidewall530is integrally formed with the top wall520, and edges where the sidewall530and top wall520meet are generally rounded.

In other example embodiments, the housing510may include four sidewalls530that meet at corners (not shown).

In at least one example embodiment, a charging slot540is formed in the top wall520of the housing510. The charging slot540may be generally cylindrical. The charging slot540is defined by a bottom wall600and at least one internal side wall610. The charging slot540may be sized and configured to receive the second end220of the e-vaping device60. The bottom wall600may be generally flat. In other example embodiments, the bottom wall600may include bumps or curves.

In at least one example embodiment, a light pipe550substantially surrounds the charging slot540. The light pipe550is generally tubular in shape, such that when the second end220of the e-vaping device60is inserted in the charging slot540, the second end220passes through the light pipe550. The light pipe550may include an extension550athat extends through an internal compartment525and through a portion of the sidewall530, such that the extension550ais visible at a first end605of the charger500. The light pipe550may be formed of a substantially transparent material that allows light from the e-vaping device60to be viewed while the e-vaping device60is docked in the charging slot540. An apex505of the top wall520may be about a same height as a top surface of the light pipe550.

In at least one example embodiment, the charger500also includes a USB plug560. In other example embodiments, instead of a USB plug560, a mini-USB plug or other power connection plug may be included with the charger500. The charger500may be connected to a power source via the USB plug560to allow charging of the battery1of the e-vaping device60connected to the charger500.

In at least one example embodiment, the housing510is smooth. In other example embodiments, the housing510may include bumps and/or ridges that assist in gripping of the charger500when plugging the USB plug560into an outlet or removing the USB plug560from the outlet.

FIG. 10is a top view of the charger ofFIG. 10according to at least one example embodiment.FIG. 12is a cross-sectional view of the charger ofFIG. 10along line XII-XII according to at least one example embodiment.

In at least one example embodiment, the charger500is the same as inFIG. 9. As shown, the charger500includes a first charging contact630and a second charging contact640. At least one of the first charging contact630and the second charging contact640may be magnetic. The first charging contact630has a T-shaped cross-section with a circular, flat top surface projecting up into the charging slot540. The first charging contact630is sized and configured to attract and/or contact the first contact310of the e-vaping device60so as to form a first electrical connection therewith and align the second end220of the e-vaping device60within the charging slot540. The second charging contact640is cylindrical with a top surface having in inwardly projecting flange. The second charging contact640surrounds the first charging contact630, and is electrically insulated from the first charging contact630by an insulator635. The insulator635is cylindrical with a top surface having an outwardly projecting flange. The second charging contact640is sized and configured to attract and/or contact the second contact320of the e-vaping device60so as to form a second electrical connection therewith and align the second end220of the e-vaping device60within the charging slot540. The first charging contact630and/or the second charging contact640may be formed of magnetic stainless steel or any other suitable material that provides good conduction and is magnetic.

As shown inFIG. 12, the internal components of the charger500are shown arranged within the internal compartment525. As shown, the USB plug560extends through a sidewall520of the housing510into the internal compartment525. The USB plug560is in direct electrical communication with a charger printed circuit board650, which is in electrical communication with the first charging contact630and the second charging contact640via leads645,647. A magnet683is positioned beneath a portion of the second charging contact640and between the insulator635and the second charging contact640. The flanges of the insulator635and the second charging contact640extend over the top surface of the magnet683. The magnet683is cylindrical and the first charging contact630extends through a center of the magnet683. The first charging contact630may be biased upwards into the charging slot by a spring632disposed within the insulator635such that the first charging contact630has a top surface that is above a top surface of the second charging contact640when no e-vaping device60is inserted in the charging slot540.FIG. 13shows an exploded view of a charger contact assembly of the charger ofFIGS. 9-12.FIG. 11is an exploded view of the charger ofFIG. 9. In at least one example embodiment, a shroud675at least partially surrounds the light tube550. The shroud675may substantially prevent and/or reduce visibility of light through a portion of the light tube550. As shown, the light tube550may include a first tubular portion552, and the extension554, which extends through an outlet in the sidewall525.