WO2022263260A1 - Electronic cigarette with remote temperature measurement - Google Patents

Electronic cigarette with remote temperature measurement Download PDF

Info

Publication number
WO2022263260A1
WO2022263260A1 PCT/EP2022/065605 EP2022065605W WO2022263260A1 WO 2022263260 A1 WO2022263260 A1 WO 2022263260A1 EP 2022065605 W EP2022065605 W EP 2022065605W WO 2022263260 A1 WO2022263260 A1 WO 2022263260A1
Authority
WO
WIPO (PCT)
Prior art keywords
temperature
heater
electronic cigarette
temperature sensor
power pack
Prior art date
Application number
PCT/EP2022/065605
Other languages
French (fr)
Inventor
Olayiwola Olamiposi POPOOLA
Original Assignee
Jt International Sa
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Jt International Sa filed Critical Jt International Sa
Publication of WO2022263260A1 publication Critical patent/WO2022263260A1/en

Links

Classifications

    • A—HUMAN NECESSITIES
    • A24—TOBACCO; CIGARS; CIGARETTES; SIMULATED SMOKING DEVICES; SMOKERS' REQUISITES
    • A24F—SMOKERS' REQUISITES; MATCH BOXES; SIMULATED SMOKING DEVICES
    • A24F40/00—Electrically operated smoking devices; Component parts thereof; Manufacture thereof; Maintenance or testing thereof; Charging means specially adapted therefor
    • A24F40/50—Control or monitoring
    • A24F40/57—Temperature control
    • A—HUMAN NECESSITIES
    • A24—TOBACCO; CIGARS; CIGARETTES; SIMULATED SMOKING DEVICES; SMOKERS' REQUISITES
    • A24F—SMOKERS' REQUISITES; MATCH BOXES; SIMULATED SMOKING DEVICES
    • A24F40/00—Electrically operated smoking devices; Component parts thereof; Manufacture thereof; Maintenance or testing thereof; Charging means specially adapted therefor
    • A24F40/50—Control or monitoring
    • A24F40/51—Arrangement of sensors
    • A—HUMAN NECESSITIES
    • A24—TOBACCO; CIGARS; CIGARETTES; SIMULATED SMOKING DEVICES; SMOKERS' REQUISITES
    • A24F—SMOKERS' REQUISITES; MATCH BOXES; SIMULATED SMOKING DEVICES
    • A24F40/00—Electrically operated smoking devices; Component parts thereof; Manufacture thereof; Maintenance or testing thereof; Charging means specially adapted therefor
    • A24F40/10—Devices using liquid inhalable precursors

Definitions

  • the present invention relates to personal vaporizing devices, such as electronic cigarettes.
  • the invention relates to an electronic cigarette with a system to measure the temperature of a heater in a disposable capsule.
  • Electronic cigarettes are an alternative to conventional cigarettes. Instead of generating a combustion smoke, they vaporize an aerosol-forming substance, which can be inhaled by a user.
  • the aerosol-forming substance is a liquid, such as glycerine or propylene glycol that creates the vapour.
  • the aerosol-forming substance is solid or semi solid and aerosol may be generated by heating the substance rather than burning it.
  • other common substances in the liquid are nicotine and various flavourings.
  • An electronic cigarette is typically a hand-held inhaler system, comprising a mouthpiece section, a liquid store, a power supply unit. Vaporization is achieved by supplying power to a vaporizer or heater unit which typically comprises a heating element in the form of a heating coil and a fluid transfer element such as a wick. The vaporization occurs as the heater heats up the liquid in the wick until the liquid is transformed into vapour.
  • a vaporizer or heater unit typically comprises a heating element in the form of a heating coil and a fluid transfer element such as a wick.
  • the vaporization occurs as the heater heats up the liquid in the wick until the liquid is transformed into vapour.
  • the heater and the liquid store are housed in a disposable capsule, often referred to as a ‘cartomizer’.
  • Other non-disposable components such as the power supply unit are housed in the main body, or ‘power pack’, of the electronic cigarette, which has a chamber configured to receive the disposable capsule.
  • an electronic cigarette power pack configured to supply power to a removable capsule, the removable capsule containing a heater configured to vaporise an aerosol forming substance
  • the electronic cigarette power pack comprising: a power source; electrical contacts configured to connect the power source to the heater in the removable capsule; and a temperature sensor configured to measure the temperature of the heater in the removable capsule, wherein the temperature sensor is located in an airflow path to the heater.
  • the power supplied by the power pack can be adjusted so that the heater remains at an optimum operating temperature.
  • there may be an optimum temperature of the heater which results in more consistent vaporisation of the aerosol forming substance, and/or a preferred temperature of the vapour to be inhaled by a user. Therefore the ability to maintain the heater at the optimum temperature can lead to improved consumer satisfaction.
  • the power efficiency and overall performance of the device can be improved, and components can be prevented from overheating and/or failure.
  • the temperature of the heater can be determined remotely, which means that the temperature sensor does not need to be a disposable component housed in the removable capsule. This can reduce the cost to manufacture the capsules.
  • the temperature measured by the temperature sensor can be correlated with the temperature of the heater, which will allow an accurate value for the heater’s temperature to be determined.
  • the electronic cigarette power pack may further comprise a resistive element electrically connected to the power source, wherein the temperature sensor is positioned so that it can detect heat generated by the resistive element.
  • the resistive element will also generate heat in proportion to the heat generated by the heater, so measuring the heat generated by the resistive element can help provide a more accurate measurement of the temperature of the heater.
  • the resistive element may comprise a resistor, any component with electrical resistance, or any component that generates heat when electrical power is supplied to it.
  • the resistive element is electrically connected in series with the heater when the removable capsule is connected to the electrical contacts.
  • this divides the power supplied by the power pack between the resistive element and the heater, such that heat generated by the resistive element is directly proportional to heat generated by the heater. This may simplify a calculation of the temperature of the heater based on the temperature measured by the temperature sensor.
  • the resistive element has an electrical resistance smaller than that of the heater.
  • this ensures that the majority of the power supplied by the power pack is used by the heater to vaporise the aerosol forming substance. In other words, less energy is used by the resistive element compared to the heater to supply heat to the temperature sensor, which improves the power efficiency of the electronic cigarette power pack when in use.
  • the resistive element has an electrical resistance that is at least an order of magnitude smaller than that of the heater.
  • the resistive element by configuring the resistive element to have an electrical resistance that is significantly smaller than that of the heater, only a small amount of energy is used by the resistive element to supply heat to the temperature sensor. Since almost all the energy supplied by the power pack in use is used to vaporise the aerosol forming substance, the power efficiency of the electronic cigarette power pack is improved.
  • the temperature sensor is positioned between the resistive element and the heater, in use.
  • the electronic cigarette power pack may further comprise a processor configured to calculate the temperature of the heater based on the temperature measured by the temperature sensor and a predetermined relationship.
  • the predetermined relationship may be calculated using test data previously gathered using an identical capsule and power pack.
  • the processor is further configured to calculate the temperature of the heater based on a measurement of the ambient temperature by the temperature sensor that is taken before power is supplied to the heater by the power source, or a measurement of the ambient temperature by a separate temperature sensor.
  • this allows the processor to compensate for changes in the ambient temperature so that an accurate value of the temperature of the heater can still be provided.
  • the ambient temperature may be a variable accounted for in the predetermined relationship used by the processor.
  • the electronic cigarette power pack may further comprise a control unit configured to control the power supplied to the heater based on the temperature measured by the temperature sensor.
  • the control unit allows the power supplied to the heater to be changed if the calculated temperature of the heater is different from an optimum operating temperature of the heater.
  • the control unit may take the calculated temperature of the heater as an input, and use it to adjust the power supplied by the power source, so that the temperature of the heater becomes closer to the optimum operating temperature.
  • an electronic cigarette comprising the electronic cigarette power pack as defined above and the removable capsule, the removable capsule containing the heater.
  • a method for measuring the temperature of a heater located in a capsule that is removable from an electronic cigarette power pack as defined above comprising the steps of: measuring a temperature at the temperature sensor; and calculating a temperature of the heater based on the temperature measured by the temperature sensor.
  • Apparatus features may be provided as method features and vice-versa.
  • an electronic cigarette power pack configured to supply power to a removable capsule, the removable capsule containing a heater configured to vaporise an aerosol forming substance
  • the electronic cigarette power pack comprising: a power source; electrical contacts configured to connect the power source to the heater in the capsule; a temperature sensor configured to measure the temperature of the heater in the removable capsule; and a resistive element electrically connected to the power source, wherein the temperature sensor is configured to detect heat generated by the resistive element.
  • Fig. 1a is a perspective view of an electronic cigarette in an embodiment of the invention.
  • Fig. 1 b is a perspective side view of the electronic cigarette of figure 1a;
  • Fig. 1c is a schematic cross-sectional view of the electronic cigarette of figures 1a and 1b.
  • Fig. 2a is a perspective view of the electronic cigarette in figures 1a and 1b, wherein the capsule has been disconnected from the main body.
  • Fig. 2b is a perspective view of a capsule seating inside the main body shown in figure 2a.
  • Fig. 3 is a schematic cross-sectional view of an electronic cigarette according to an exemplary embodiment of the present invention.
  • Fig. 4a is a graph showing exemplary data used to calibrate the electronic cigarette.
  • Fig. 4b is a graph showing a calibration relationship derived from the data depicted in figure 4a.
  • Fig. 5 is a graph showing the temperature of various components of an electronic cigarette during a vaporising session.
  • the electronic cigarette 2 can be used as a substitute for a conventional cigarette.
  • the electronic cigarette 2 has a main body 4 comprising a power supply unit 6, electrical circuitry 8 and a capsule seating 12.
  • the capsule seating 12 is configured to receive a removable capsule 16 comprising a vaporizing liquid.
  • the liquid may comprise an aerosol-forming substance such as propylene glycol and/or glycerol and may contain other substances such as nicotine and acids.
  • the liquid may also comprise flavourings such as tobacco, menthol or fruit flavour.
  • the capsule seating 12 is preferably in the form of a cavity configured to receive the capsule 16.
  • the capsule seating 12 is provided with a connection portion 21 configured to hold the capsule 16 firmly to the capsule seating 12.
  • the connection portion 21 could be an interference fit, a snap fit, a screw fit, a bayoneted fit or a magnetic fit.
  • the capsule seating 12 further comprises a pair of electrical connectors 14 configured to engage with corresponding power terminals 45 on the capsule 16.
  • the capsule 16 has a mouthpiece portion 20 and a vaporizing chamber which is surrounded by a liquid store 32.
  • the vaporizing chamber receives liquid from the liquid store 32 and air from one or more air inlets 35, and transports vapour through a channel 24 leading to an outlet 28 on the mouthpiece portion 20.
  • the air inlets 35 are located on the end 17 of the capsule 16 that is inserted into the capsule seating 12 of the main body 4.
  • the vaporizing chamber contains a heating element 36 and a fluid transfer element (not shown), which is configured to transfer the liquid by capillary action from the liquid store 32 to the heating element 36.
  • the heating element 36 may be a coil that is wound around the fluid transfer element.
  • the power terminals 45 of the capsule 16 are electrically connected to the heating element 36, such that resistive heating causes it to heat up when power is supplied by the power supply unit 6.
  • the main body 4 is configured to supply power to the heating element 36 in the capsule 16 and to control the overall operation of the vaporization.
  • the main body 4 can be configured as a compact device in comparison to most prior art electronic cigarettes. This means that the power supply unit 6 is relatively small in size.
  • the power supply unit 6 may comprise a battery such as a lithium battery with an output of about 350mAh.
  • the electrical circuitry 8 of the main body 4 is configured to operate the electronic cigarette 2 and may comprise a flow sensor 10 or a manual activation switch, a processor 11 and a controller 13.
  • the electrical circuitry 8 may be grouped onto a main printed circuit board.
  • the controller 13 is configured to enable pulse width modulation (PWM) of the battery output.
  • PWM pulse width modulation
  • the pulse width modulation controls the temperature of the heating element 36 and enables saving of the battery power.
  • the output power is modulated such that the output power is constant over time, regardless of whether the battery is full or close to depletion. This is advantageous as the present battery is relatively small in size and output voltage.
  • the temperature of the heating element is at a temperature at which an efficient vaporization occurs. This is because if the temperature of the heating coil is insufficient, the liquid is prone to get into a boiling stage rather than a desired vaporization state. In one example, the liquid vaporises at 230°C. It is desirable to ensure a sufficiently high heating element temperature such that the liquid transforms straight into the vaporization state. Thereby, undesirable liquid projections can be alleviated. Additionally, it would be desirable to provide a high vapour volume with a high TPM (Total Particulate Matter), while keeping the amount of undesirable chemical compounds at a low level. For this reason it is desirable to monitor the temperature of the heating element 36 throughout use of the electronic cigarette 2.
  • TPM Total Particulate Matter
  • FIG. 3 depicts a schematic view of an advantageous variation of the electronic cigarette 2, with the capsule 16 partially inserted into the capsule seating 12 in the main body 4.
  • the main body 4 of the electronic cigarette 2 has a temperature sensor 40 located between the two electrical connectors 14.
  • the temperature sensor 40 borders the cavity defined by the capsule seating 12, which means that during use of the electronic cigarette 2, the temperature sensor 40 is located in an airflow pathway to the heating element 36.
  • the airflow pathway through the electronic cigarette 2 is indicated by arrows, which pass around the capsule 16 into the capsule seating 12, into the air inlets 35, past the heating element 36, and through the channel 24 towards the outlet 28 on the mouthpiece portion 20.
  • the temperature sensor 40 is located near the air inlets 35, thereby placing the temperature sensor 40 in an airflow pathway to the heating element 36. In this way, the temperature sensor 40 will be more sensitive to changes in temperature of the heating element 36 and will monitor the temperature of the heating element 36 more closely.
  • a resistor 42 is positioned in close proximity to the temperature sensor 40.
  • the resistor 42 is electrically connected in series with the heating element 36 and the power supply unit 6. In this way, power will be dissipated through both the resistor 42 and the heating element 36 in proportion to their respective resistances.
  • the resistor 42 is selected to have a lower resistance than the heating element 36, preferably at least an order of magnitude lower.
  • the heating element 36 has a resistance of about 2W and the resistor 42 has a resistance of about 0.1 W. In this example, if the heating element 36 dissipates 8W of power, the resistor 42 dissipates 0.4W of power.
  • the temperature sensor 40 Since the temperature sensor 40 is in close proximity to the resistor 42, and is also in an airflow pathway to the heating element 36, the temperature sensor 40 receives heat from both the resistor 42 and the heating element 36. Due to its position in the device, the temperature sensor 40 may not measure the exact temperature of either the heating element 36 or the resistor 42, but it will provide a temperature that is correlated with the temperature of the heating element 36. It is beneficial for the temperature sensor 40 to be provided with as much heat as possible since, as will be described later, the measured temperature will be scaled up to estimate the temperature of the heating element 36. In this way, background noise, random fluctuations and/or rounding errors due to the limited precision of the temperature sensor 40 have a reduced significance when estimating the temperature of the heating element 36.
  • the processor 11 of the electrical circuitry 8 is configured to receive the temperature measured by the temperature sensor 40 and calculate the temperature of the heating element 36. As will be described in detail below, the processor 11 may use a calibration relationship that takes the temperature measured at the temperature sensor 40 as an input and gives an estimated temperature of the heating element 36 as an output. The processor 11 may then compare this estimated temperature with an optimum operating temperature for the heating element 36, and send instructions to the controller 13 to adjust the output power of the power supply unit 6. Since the temperature sensor 40 can provide data throughout use of the electronic cigarette 2, the power output of the power supply unit 6 can be frequently adjusted so that the heating element 36 remains at its optimum temperature.
  • the controller 13 may increase a duty cycle of the PWM signal. This increases the power supplied by the power supply unit 6, thereby raising the temperature of the heating element 36. In this way, the vapour received by the user will have an ideal temperature and/or TPM, which will increase the user experience.
  • the controller 13 may decrease the duty cycle of the PWM signal. This decreases the power supplied by the power supply unit 6, thereby lowering the temperature of the heating element 36. In this way, the risk of overheating is reduced and the lifetime of the battery and/or the liquid store 32 may be extended.
  • the calibration relationship may be a predetermined relationship using data collected from a test device.
  • the test device may be otherwise identical to the electronic cigarette 2, with additional test temperature sensors located throughout the device, such as directly at the heating element 36.
  • additional test temperature sensors located throughout the device, such as directly at the heating element 36.
  • the power supply unit 6 supplies power to the heating element 36
  • all the temperature sensors monitor the temperature at their respective locations across a range of input power levels.
  • FIG 4a shows a simplified example of data collected in such a test.
  • the power supplied to the heating element 36 is varied over a wide range of values, and the temperature of the heating element 36 is monitored both directly with a test temperature sensor (line 401), and indirectly with the temperature sensor 40 located in the main body 4 of the electronic cigarette 2 (line 402).
  • the temperature sensor 40 measures a temperature that is lower than the actual temperature of the heating element 36, but the values are proportional to each other. Therefore, this data can be used to create a calibration relationship like the one shown in figure 4b.
  • This calibration relationship (line 403) takes a temperature measured by the temperature sensor 40 on the x-axis and converts it to a calculated temperature of the heating element 36 on the y-axis.
  • the calibration relationship may be stored in the electronics 8 of the electronic cigarette 2, and used by the processor 11 to convert the temperature measured at the temperature sensor 40 into an estimate for the actual temperature at the heating element 36.
  • the controller 13 may vary the power supplied by the power supply unit 6 so that the heating element 36 operates at its optimum temperature.
  • figure 4b represents the calibration relationship as a graph, it may equivalently be stored as a lookup table, an equation, or any other suitable storage method.
  • the data shown in figures 4a and 4b was based on a starting temperature of 25°C, the relationship preferably accounts for the starting temperature (or ambient temperature) of the device.
  • the relationship may be expressed using the following equation:
  • Heater Temp Start Temp + M c (Measured Temp - Start Temp)
  • M the gradient of the line
  • M the gradient of the line
  • M the gradient of the line
  • M the gradient of the line
  • the starting temperature used in this equation may be the temperature measured at the temperature sensor 40 before any power is supplied to the heating element 36, such as when the electronic cigarette 2 is first switched on.
  • the start temperature may be determined from a separate temperature sensor, which is a larger distance from the heating element 36 and/or the resistor 42.
  • the starting temperature may be equivalent to the ambient temperature of the surroundings of the electronic cigarette 2.
  • Other calibration relationships can be used which depend on the starting/ambient temperature or the measured temperature in different ways. These relationships may be non-linear, or may be based on test data collected at many different starting temperatures and/or using many different test devices.
  • figure 5 shows data from an experiment where the temperature is measured at five different sensors in a test device throughout a vaporising session.
  • the power output of the power supply unit 6 is not adjusted based on the measured temperature.
  • Line 501 corresponds to the temperature measured by the temperature sensor 40;
  • line 502 corresponds to the temperature measured at the battery;
  • line 503 corresponds to the temperature measured at the device casing;
  • lines 504 and 505 correspond to the temperature measured at two temperature sensors placed either side of the heating element 36 inside the capsule 16.
  • 25 puffs were taken from the device, with each puff corresponding to a spike in the temperature measured by the temperature sensor 40.
  • the maximum temperature of each spike on line 501 gradually increases throughout the session, which indicates that the peak temperature of the heating element 36 also increases throughout the session.
  • the controller 13 is not adjusting the output power of the power supply unit 6 to compensate for this temperature rise.
  • puffs taken near the start of the session may have an insufficient TPM levels, and later puffs may have TPM levels that are too high.
  • the controller 13 may increase the power supplied by the power supply unit 6 at the start of the session, and decrease the power supplied near the end of the session, such that the peaks on line 501 appear at substantially the same height in all puffs. In this way, the TPM levels remain consistent, and the device has increased power efficiency.
  • controller 13 and processor 11 have been described as separate components, the control steps are not limited to being performed by the controller 13, and the processing steps are not limited to being performed by the processor 11 . Indeed, the controller and the processor may be configured as a single component and/or may perform other steps during using the device. While the foregoing is directed to exemplary embodiments of the present invention, it will be understood that the present invention is described herein purely by way of example, and modifications can be made within the scope of the invention. Indeed, other and further embodiments of the invention will be apparent to those skilled in the art from consideration of the specification, and may be devised without departing from the basic scope thereof, which is determined by the claims that follow.

Landscapes

  • Control Of Temperature (AREA)

Abstract

An electronic cigarette (2) with remote temperature measurement is disclosed. The electronic cigarette (2) includes a power pack (4) configured to supply power to a removable capsule (16), the removable capsule (16) containing a heater (36) configured to vaporise an aerosol forming substance. The power pack (4) includes a power source (6); electrical contacts (14, 45) configured to connect the power source (6) to the heater (36) in the removable capsule (16); and a temperature sensor (40) configured to measure the temperature of the heater (36) in the removable capsule (16). The temperature sensor (40) is located in an airflow path to the heater (36). The electronic cigarette power pack (4) also includes a resistive element (42) electrically connected to the power source (6), wherein the temperature sensor (40) is positioned so that it can detect heat generated by the resistive element (42).

Description

ELECTRONIC CIGARETTE WITH REMOTE TEMPERATURE MEASUREMENT
FIELD OF INVENTION
The present invention relates to personal vaporizing devices, such as electronic cigarettes. In particular, the invention relates to an electronic cigarette with a system to measure the temperature of a heater in a disposable capsule.
BACKGROUND
Electronic cigarettes are an alternative to conventional cigarettes. Instead of generating a combustion smoke, they vaporize an aerosol-forming substance, which can be inhaled by a user. In some arrangements the aerosol-forming substance is a liquid, such as glycerine or propylene glycol that creates the vapour. In other arrangements the aerosol-forming substance is solid or semi solid and aerosol may be generated by heating the substance rather than burning it. Where a liquid aerosol-forming substance is used, other common substances in the liquid are nicotine and various flavourings.
An electronic cigarette is typically a hand-held inhaler system, comprising a mouthpiece section, a liquid store, a power supply unit. Vaporization is achieved by supplying power to a vaporizer or heater unit which typically comprises a heating element in the form of a heating coil and a fluid transfer element such as a wick. The vaporization occurs as the heater heats up the liquid in the wick until the liquid is transformed into vapour. In some configurations, the heater and the liquid store are housed in a disposable capsule, often referred to as a ‘cartomizer’. Other non-disposable components such as the power supply unit are housed in the main body, or ‘power pack’, of the electronic cigarette, which has a chamber configured to receive the disposable capsule. It is desirable to monitor the temperature of the heater during use of the electronic cigarette, since the operating temperature of the heater will affect the temperature and the amount of aerosol-forming substance in the vapour that is received by the user. If the temperature of the heater is not at its optimum level, then the user experience and the efficiency of the electronic cigarette may be reduced. For this reason, it has been considered in some arrangements to place a temperature sensor adjacent the heater. This arrangement is beneficial in that it can closely monitor the temperature of the heater. However, such an arrangement can also increase the cost of the disposable capsule, which is undesirable for consumers. An object of the present invention is to address these issues.
SUMMARY OF THE INVENTION
According to a first aspect of the present invention there is provided an electronic cigarette power pack configured to supply power to a removable capsule, the removable capsule containing a heater configured to vaporise an aerosol forming substance, the electronic cigarette power pack comprising: a power source; electrical contacts configured to connect the power source to the heater in the removable capsule; and a temperature sensor configured to measure the temperature of the heater in the removable capsule, wherein the temperature sensor is located in an airflow path to the heater.
Advantageously, by measuring the temperature of the heater throughout use, the power supplied by the power pack can be adjusted so that the heater remains at an optimum operating temperature. For example, there may be an optimum temperature of the heater which results in more consistent vaporisation of the aerosol forming substance, and/or a preferred temperature of the vapour to be inhaled by a user. Therefore the ability to maintain the heater at the optimum temperature can lead to improved consumer satisfaction. Similarly, by preventing the power pack from supplying too much power to the heater, the power efficiency and overall performance of the device can be improved, and components can be prevented from overheating and/or failure. Furthermore, by placing the temperature sensor in the power pack, the temperature of the heater can be determined remotely, which means that the temperature sensor does not need to be a disposable component housed in the removable capsule. This can reduce the cost to manufacture the capsules. By placing the sensor in an airflow path to the heater, the temperature measured by the temperature sensor can be correlated with the temperature of the heater, which will allow an accurate value for the heater’s temperature to be determined.
The electronic cigarette power pack may further comprise a resistive element electrically connected to the power source, wherein the temperature sensor is positioned so that it can detect heat generated by the resistive element. Advantageously, the resistive element will also generate heat in proportion to the heat generated by the heater, so measuring the heat generated by the resistive element can help provide a more accurate measurement of the temperature of the heater. The resistive element may comprise a resistor, any component with electrical resistance, or any component that generates heat when electrical power is supplied to it.
Preferably, the resistive element is electrically connected in series with the heater when the removable capsule is connected to the electrical contacts. Advantageously, this divides the power supplied by the power pack between the resistive element and the heater, such that heat generated by the resistive element is directly proportional to heat generated by the heater. This may simplify a calculation of the temperature of the heater based on the temperature measured by the temperature sensor.
Preferably, the resistive element has an electrical resistance smaller than that of the heater. Advantageously, this ensures that the majority of the power supplied by the power pack is used by the heater to vaporise the aerosol forming substance. In other words, less energy is used by the resistive element compared to the heater to supply heat to the temperature sensor, which improves the power efficiency of the electronic cigarette power pack when in use.
Preferably, the resistive element has an electrical resistance that is at least an order of magnitude smaller than that of the heater. Advantageously, by configuring the resistive element to have an electrical resistance that is significantly smaller than that of the heater, only a small amount of energy is used by the resistive element to supply heat to the temperature sensor. Since almost all the energy supplied by the power pack in use is used to vaporise the aerosol forming substance, the power efficiency of the electronic cigarette power pack is improved.
Preferably, the temperature sensor is positioned between the resistive element and the heater, in use. Advantageously, this means that the temperature sensor can receive heat from both the heater and the resistive element, thereby improving the correlation between the temperature measured by the temperature sensor and the actual temperature of the heater.
The electronic cigarette power pack may further comprise a processor configured to calculate the temperature of the heater based on the temperature measured by the temperature sensor and a predetermined relationship. The predetermined relationship may be calculated using test data previously gathered using an identical capsule and power pack.
Preferably, the processor is further configured to calculate the temperature of the heater based on a measurement of the ambient temperature by the temperature sensor that is taken before power is supplied to the heater by the power source, or a measurement of the ambient temperature by a separate temperature sensor. Advantageously, this allows the processor to compensate for changes in the ambient temperature so that an accurate value of the temperature of the heater can still be provided. For example the ambient temperature may be a variable accounted for in the predetermined relationship used by the processor. The electronic cigarette power pack may further comprise a control unit configured to control the power supplied to the heater based on the temperature measured by the temperature sensor. Advantageously, the control unit allows the power supplied to the heater to be changed if the calculated temperature of the heater is different from an optimum operating temperature of the heater. The control unit may take the calculated temperature of the heater as an input, and use it to adjust the power supplied by the power source, so that the temperature of the heater becomes closer to the optimum operating temperature.
According to another aspect of the present invention, there is provided an electronic cigarette comprising the electronic cigarette power pack as defined above and the removable capsule, the removable capsule containing the heater.
According to another aspect of the present invention there is provided a method for measuring the temperature of a heater located in a capsule that is removable from an electronic cigarette power pack as defined above, the method comprising the steps of: measuring a temperature at the temperature sensor; and calculating a temperature of the heater based on the temperature measured by the temperature sensor.
Apparatus features may be provided as method features and vice-versa.
According to another aspect of the present invention there is provided an electronic cigarette power pack configured to supply power to a removable capsule, the removable capsule containing a heater configured to vaporise an aerosol forming substance, the electronic cigarette power pack comprising: a power source; electrical contacts configured to connect the power source to the heater in the capsule; a temperature sensor configured to measure the temperature of the heater in the removable capsule; and a resistive element electrically connected to the power source, wherein the temperature sensor is configured to detect heat generated by the resistive element. According to yet another aspect of the invention there is provided a method for measuring the temperature of a heater located in a capsule that is removable from an electronic cigarette power pack as defined above.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention are now described, by way of example, with reference to the drawings, in which:
Fig. 1a is a perspective view of an electronic cigarette in an embodiment of the invention;
Fig. 1 b is a perspective side view of the electronic cigarette of figure 1a;
Fig. 1c is a schematic cross-sectional view of the electronic cigarette of figures 1a and 1b.
Fig. 2a is a perspective view of the electronic cigarette in figures 1a and 1b, wherein the capsule has been disconnected from the main body.
Fig. 2b is a perspective view of a capsule seating inside the main body shown in figure 2a.
Fig. 3 is a schematic cross-sectional view of an electronic cigarette according to an exemplary embodiment of the present invention.
Fig. 4a is a graph showing exemplary data used to calibrate the electronic cigarette.
Fig. 4b is a graph showing a calibration relationship derived from the data depicted in figure 4a. Fig. 5 is a graph showing the temperature of various components of an electronic cigarette during a vaporising session.
DETAILED DESCRIPTION
Referring to the drawings and in particular to figures 1a to 1c, 2a, 2b and 3 an electronic cigarette 2 for vaporizing a liquid is illustrated. The electronic cigarette 2 can be used as a substitute for a conventional cigarette. The electronic cigarette 2 has a main body 4 comprising a power supply unit 6, electrical circuitry 8 and a capsule seating 12. The capsule seating 12 is configured to receive a removable capsule 16 comprising a vaporizing liquid. The liquid may comprise an aerosol-forming substance such as propylene glycol and/or glycerol and may contain other substances such as nicotine and acids. The liquid may also comprise flavourings such as tobacco, menthol or fruit flavour.
The capsule seating 12 is preferably in the form of a cavity configured to receive the capsule 16. The capsule seating 12 is provided with a connection portion 21 configured to hold the capsule 16 firmly to the capsule seating 12. The connection portion 21 could be an interference fit, a snap fit, a screw fit, a bayoneted fit or a magnetic fit. The capsule seating 12 further comprises a pair of electrical connectors 14 configured to engage with corresponding power terminals 45 on the capsule 16.
The capsule 16 has a mouthpiece portion 20 and a vaporizing chamber which is surrounded by a liquid store 32. The vaporizing chamber receives liquid from the liquid store 32 and air from one or more air inlets 35, and transports vapour through a channel 24 leading to an outlet 28 on the mouthpiece portion 20. As can be seen in figure 2a, the air inlets 35 are located on the end 17 of the capsule 16 that is inserted into the capsule seating 12 of the main body 4. The vaporizing chamber contains a heating element 36 and a fluid transfer element (not shown), which is configured to transfer the liquid by capillary action from the liquid store 32 to the heating element 36. The heating element 36 may be a coil that is wound around the fluid transfer element. The power terminals 45 of the capsule 16 are electrically connected to the heating element 36, such that resistive heating causes it to heat up when power is supplied by the power supply unit 6.
The main body 4 is configured to supply power to the heating element 36 in the capsule 16 and to control the overall operation of the vaporization. The main body 4 can be configured as a compact device in comparison to most prior art electronic cigarettes. This means that the power supply unit 6 is relatively small in size. The power supply unit 6 may comprise a battery such as a lithium battery with an output of about 350mAh.
The electrical circuitry 8 of the main body 4 is configured to operate the electronic cigarette 2 and may comprise a flow sensor 10 or a manual activation switch, a processor 11 and a controller 13. The electrical circuitry 8 may be grouped onto a main printed circuit board. The controller 13 is configured to enable pulse width modulation (PWM) of the battery output. The pulse width modulation controls the temperature of the heating element 36 and enables saving of the battery power. The output power is modulated such that the output power is constant over time, regardless of whether the battery is full or close to depletion. This is advantageous as the present battery is relatively small in size and output voltage.
It is desirable to ensure that the temperature of the heating element is at a temperature at which an efficient vaporization occurs. This is because if the temperature of the heating coil is insufficient, the liquid is prone to get into a boiling stage rather than a desired vaporization state. In one example, the liquid vaporises at 230°C. It is desirable to ensure a sufficiently high heating element temperature such that the liquid transforms straight into the vaporization state. Thereby, undesirable liquid projections can be alleviated. Additionally, it would be desirable to provide a high vapour volume with a high TPM (Total Particulate Matter), while keeping the amount of undesirable chemical compounds at a low level. For this reason it is desirable to monitor the temperature of the heating element 36 throughout use of the electronic cigarette 2. Figure 3 depicts a schematic view of an advantageous variation of the electronic cigarette 2, with the capsule 16 partially inserted into the capsule seating 12 in the main body 4. In addition to the other components described above, the main body 4 of the electronic cigarette 2 has a temperature sensor 40 located between the two electrical connectors 14. The temperature sensor 40 borders the cavity defined by the capsule seating 12, which means that during use of the electronic cigarette 2, the temperature sensor 40 is located in an airflow pathway to the heating element 36. The airflow pathway through the electronic cigarette 2 is indicated by arrows, which pass around the capsule 16 into the capsule seating 12, into the air inlets 35, past the heating element 36, and through the channel 24 towards the outlet 28 on the mouthpiece portion 20. The temperature sensor 40 is located near the air inlets 35, thereby placing the temperature sensor 40 in an airflow pathway to the heating element 36. In this way, the temperature sensor 40 will be more sensitive to changes in temperature of the heating element 36 and will monitor the temperature of the heating element 36 more closely.
A resistor 42 is positioned in close proximity to the temperature sensor 40. The resistor 42 is electrically connected in series with the heating element 36 and the power supply unit 6. In this way, power will be dissipated through both the resistor 42 and the heating element 36 in proportion to their respective resistances. To ensure that the majority of the power from the power supply 6 is dissipated in the heating element 36, the resistor 42 is selected to have a lower resistance than the heating element 36, preferably at least an order of magnitude lower. In one example, the heating element 36 has a resistance of about 2W and the resistor 42 has a resistance of about 0.1 W. In this example, if the heating element 36 dissipates 8W of power, the resistor 42 dissipates 0.4W of power.
Since the temperature sensor 40 is in close proximity to the resistor 42, and is also in an airflow pathway to the heating element 36, the temperature sensor 40 receives heat from both the resistor 42 and the heating element 36. Due to its position in the device, the temperature sensor 40 may not measure the exact temperature of either the heating element 36 or the resistor 42, but it will provide a temperature that is correlated with the temperature of the heating element 36. It is beneficial for the temperature sensor 40 to be provided with as much heat as possible since, as will be described later, the measured temperature will be scaled up to estimate the temperature of the heating element 36. In this way, background noise, random fluctuations and/or rounding errors due to the limited precision of the temperature sensor 40 have a reduced significance when estimating the temperature of the heating element 36.
The processor 11 of the electrical circuitry 8 is configured to receive the temperature measured by the temperature sensor 40 and calculate the temperature of the heating element 36. As will be described in detail below, the processor 11 may use a calibration relationship that takes the temperature measured at the temperature sensor 40 as an input and gives an estimated temperature of the heating element 36 as an output. The processor 11 may then compare this estimated temperature with an optimum operating temperature for the heating element 36, and send instructions to the controller 13 to adjust the output power of the power supply unit 6. Since the temperature sensor 40 can provide data throughout use of the electronic cigarette 2, the power output of the power supply unit 6 can be frequently adjusted so that the heating element 36 remains at its optimum temperature.
For example, if the heating element 36 is determined to be below its optimum operating temperature, the controller 13 may increase a duty cycle of the PWM signal. This increases the power supplied by the power supply unit 6, thereby raising the temperature of the heating element 36. In this way, the vapour received by the user will have an ideal temperature and/or TPM, which will increase the user experience.
Alternatively, if the heating element 36 is determined to be above its optimum operating temperature, the controller 13 may decrease the duty cycle of the PWM signal. This decreases the power supplied by the power supply unit 6, thereby lowering the temperature of the heating element 36. In this way, the risk of overheating is reduced and the lifetime of the battery and/or the liquid store 32 may be extended.
The calibration relationship may be a predetermined relationship using data collected from a test device. The test device may be otherwise identical to the electronic cigarette 2, with additional test temperature sensors located throughout the device, such as directly at the heating element 36. In the test device, as the power supply unit 6 supplies power to the heating element 36, all the temperature sensors monitor the temperature at their respective locations across a range of input power levels.
Figure 4a shows a simplified example of data collected in such a test. In this example, the power supplied to the heating element 36 is varied over a wide range of values, and the temperature of the heating element 36 is monitored both directly with a test temperature sensor (line 401), and indirectly with the temperature sensor 40 located in the main body 4 of the electronic cigarette 2 (line 402). As previously described, the temperature sensor 40 measures a temperature that is lower than the actual temperature of the heating element 36, but the values are proportional to each other. Therefore, this data can be used to create a calibration relationship like the one shown in figure 4b. This calibration relationship (line 403) takes a temperature measured by the temperature sensor 40 on the x-axis and converts it to a calculated temperature of the heating element 36 on the y-axis. The calibration relationship may be stored in the electronics 8 of the electronic cigarette 2, and used by the processor 11 to convert the temperature measured at the temperature sensor 40 into an estimate for the actual temperature at the heating element 36. As already discussed, the controller 13 may vary the power supplied by the power supply unit 6 so that the heating element 36 operates at its optimum temperature.
While figure 4b represents the calibration relationship as a graph, it may equivalently be stored as a lookup table, an equation, or any other suitable storage method. Furthermore, while the data shown in figures 4a and 4b was based on a starting temperature of 25°C, the relationship preferably accounts for the starting temperature (or ambient temperature) of the device. For example, the relationship may be expressed using the following equation:
Heater Temp = Start Temp + M c (Measured Temp - Start Temp)
For the example calibration relationship in figure 4b, M (the gradient of the line) is equal to 5, but this value is dependent on the design for each specific electronic cigarette 2. The starting temperature used in this equation may be the temperature measured at the temperature sensor 40 before any power is supplied to the heating element 36, such as when the electronic cigarette 2 is first switched on. Alternatively, the start temperature may be determined from a separate temperature sensor, which is a larger distance from the heating element 36 and/or the resistor 42. The starting temperature may be equivalent to the ambient temperature of the surroundings of the electronic cigarette 2. Other calibration relationships can be used which depend on the starting/ambient temperature or the measured temperature in different ways. These relationships may be non-linear, or may be based on test data collected at many different starting temperatures and/or using many different test devices.
To demonstrate why remote temperature measurement may be useful, figure 5 shows data from an experiment where the temperature is measured at five different sensors in a test device throughout a vaporising session. In this experiment, the power output of the power supply unit 6 is not adjusted based on the measured temperature. Line 501 corresponds to the temperature measured by the temperature sensor 40; line 502 corresponds to the temperature measured at the battery; line 503 corresponds to the temperature measured at the device casing; lines 504 and 505 correspond to the temperature measured at two temperature sensors placed either side of the heating element 36 inside the capsule 16. In this vaporising session, 25 puffs were taken from the device, with each puff corresponding to a spike in the temperature measured by the temperature sensor 40. The maximum temperature of each spike on line 501 gradually increases throughout the session, which indicates that the peak temperature of the heating element 36 also increases throughout the session. In the session shown, the controller 13 is not adjusting the output power of the power supply unit 6 to compensate for this temperature rise. As a result, puffs taken near the start of the session may have an insufficient TPM levels, and later puffs may have TPM levels that are too high. Furthermore, for the later puffs, more power is supplied to the heating element 36 than is necessary for it to reach its required vaporisation temperature of 230°C, which depletes the battery faster.
In order to remove these disadvantages, the controller 13 may increase the power supplied by the power supply unit 6 at the start of the session, and decrease the power supplied near the end of the session, such that the peaks on line 501 appear at substantially the same height in all puffs. In this way, the TPM levels remain consistent, and the device has increased power efficiency.
It should be noted that while the controller 13 and processor 11 have been described as separate components, the control steps are not limited to being performed by the controller 13, and the processing steps are not limited to being performed by the processor 11 . Indeed, the controller and the processor may be configured as a single component and/or may perform other steps during using the device. While the foregoing is directed to exemplary embodiments of the present invention, it will be understood that the present invention is described herein purely by way of example, and modifications can be made within the scope of the invention. Indeed, other and further embodiments of the invention will be apparent to those skilled in the art from consideration of the specification, and may be devised without departing from the basic scope thereof, which is determined by the claims that follow.

Claims

1. An electronic cigarette power pack configured to supply power to a removable capsule, the removable capsule containing a heater configured to vaporise an aerosol forming substance, the electronic cigarette power pack comprising: a power source; electrical contacts configured to connect the power source to the heater in the removable capsule; and a temperature sensor configured to measure the temperature of the heater in the removable capsule, wherein the temperature sensor is located in an airflow path to the heater.
2. The electronic cigarette power pack of claim 1 , further comprising a resistive element electrically connected to the power source, wherein the temperature sensor is positioned so that it can detect heat generated by the resistive element.
3. The electronic cigarette power pack of claim 2, wherein the resistive element is electrically connected in series with the heater when the removable capsule is connected to the electrical contacts.
4. The electronic cigarette power pack of claim 3, wherein the resistive element has an electrical resistance that is smaller than that of the heater.
5. The electronic cigarette power pack of claim 4, wherein the resistive element has an electrical resistance that is at least an order of magnitude smaller than that of the heater.
6. The electronic cigarette power pack of any of claims 2 to 5, wherein the temperature sensor is positioned between the resistive element and the heater, in use.
7. The electronic cigarette power pack of any preceding claim, further comprising a processor configured to calculate the temperature of the heater based on the temperature measured by the temperature sensor and a predetermined relationship.
8. The electronic cigarette power pack of claim 7, wherein the processor is further configured to calculate the temperature of the heater based on a measurement of the ambient temperature by the temperature sensor that is taken before power is supplied to the heater by the power source, or a measurement of the ambient temperature by a separate temperature sensor.
9. The electronic cigarette power pack of any preceding claim, further comprising a control unit configured to control the power supplied to the heater based on the temperature measured by the temperature sensor.
10. An electronic cigarette comprising the electronic cigarette power pack of any preceding claim and the removable capsule, the removable capsule containing the heater.
11. A method for measuring the temperature of a heater located in a capsule that is removable from an electronic cigarette power pack according to any of claims 1 to 9, the method comprising the steps of: measuring a temperature at the temperature sensor; and calculating a temperature of the heater based on the temperature measured by the temperature sensor.
PCT/EP2022/065605 2021-06-15 2022-06-08 Electronic cigarette with remote temperature measurement WO2022263260A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP21179455.7 2021-06-15
EP21179455 2021-06-15

Publications (1)

Publication Number Publication Date
WO2022263260A1 true WO2022263260A1 (en) 2022-12-22

Family

ID=76483071

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2022/065605 WO2022263260A1 (en) 2021-06-15 2022-06-08 Electronic cigarette with remote temperature measurement

Country Status (1)

Country Link
WO (1) WO2022263260A1 (en)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20200281278A1 (en) * 2019-03-05 2020-09-10 Canopy Growth Corporation System and method for measuring payload dosage in a vaporization device
US20210100291A1 (en) * 2019-10-04 2021-04-08 Rai Strategic Holdings, Inc. Use of infrared temperature detection in an aerosol delivery device
EP3813484A1 (en) * 2019-10-24 2021-04-28 Japan Tobacco Inc. Power supply unit for aerosol inhaler

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20200281278A1 (en) * 2019-03-05 2020-09-10 Canopy Growth Corporation System and method for measuring payload dosage in a vaporization device
US20210100291A1 (en) * 2019-10-04 2021-04-08 Rai Strategic Holdings, Inc. Use of infrared temperature detection in an aerosol delivery device
EP3813484A1 (en) * 2019-10-24 2021-04-28 Japan Tobacco Inc. Power supply unit for aerosol inhaler

Similar Documents

Publication Publication Date Title
US11571026B2 (en) Burning prediction and communications for an electronic cigarette
US11849760B2 (en) Hot-wire control for an electronic cigarette
US20220273041A1 (en) Heating control for vaporizing device
KR101787985B1 (en) Electronic vapour provision device
US20210084985A1 (en) Power-supply unit, and flavor generating device, method and program
EP3801084B1 (en) Methods for detecting heater conditions in an aerosol-generating system
KR20170137066A (en) Apparatus and method for controlling an electric heater to limit the temperature according to a desired temperature profile over time
US20210169150A1 (en) Dual Battery Electronic Cigarette
US20210289845A1 (en) Aerosol-generating device having improved power supply controller
US20220312854A1 (en) Aerosol provision systems
JP2021531760A (en) Temperature control for personal vaporizers
US20230048555A1 (en) Aerosol provision systems
WO2022263260A1 (en) Electronic cigarette with remote temperature measurement
CA3136543C (en) Vapour provision system and corresponding method
US20230180850A1 (en) Non-combustible aerosol provision system
KR20240023025A (en) Aerosol-generating device that monitors batteries
JP2024507465A (en) Heating systems for aerosol generation assemblies and associated aerosol generation assemblies
CN117479856A (en) Aerosol generating device power monitoring
EA040566B1 (en) ELECTRONIC CIGARETTE WITH TWO BATTERIES

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22730937

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE