Electronic smoking device

Abstract

An electronic smoking (1) device comprises a housing (2), control electronics (14) and a puff detector (18). The housing (2) accommodates a battery (10) as an electric power source powering an electrically heatable atomizer (20) comprising an electric heater (22) and adapted to atomize a liquid supplied from a reservoir (6) to provide an aerosol exiting from the atomizer (20). The control electronics (14) controls the heater (22) of the atomizer (20) and is adapted to operate the heater (22) in at least two predetermined modes. The puff detector (18) indicates an aerosol inhaling puff to the control electronics (14). The control electronics (14) selects a specific mode for operating the heater (22) via a control signal initiated by the puff detector (18).

Claims

1. An electronic smoking device, comprising: a puff detector operable to detect a user sucking on or blowing into the device; an atomizer comprising a heater operable to create an aerosol for inhalation by a user by atomizing a liquid supplied from a reservoir; and control electronics responsive to the puff detector detecting a user sucking on or blowing into the device to activate the atomizer to atomize a liquid supplied from a reservoir to create an aerosol for inhalation, characterised in that: the control electronics are adapted to detect a manner of activation of the puff detector, responsive to the puff detector detecting a user sucking on or blowing into the device, and to select, on the basis of the detected manner of the activation of the puff detector, a mode of operation from a plurality of modes of operation, and to use the selected mode of operation to activate the heater.

2. The electronic smoking device according to claim 1, characterised in that the control electronics are configured to measure the time interval between two subsequent activations of the puff detector and interpret the corresponding activations of the puff detector as a control signal initiated by the puff detector for selection of a specific mode of operation, if the measured value for the time interval is within a predetermined range.

3. The electronic smoking device according to claim 1, characterised in that the control electronics are configured to measure the duration of an activation of the puff detector and to interpret the corresponding activation of the puff detector as a control signal initiated by the puff detector for selection of a specific mode of operation, if the measured value for the duration is within a predetermined range.

4. The electronic smoking device according to claim 2, wherein the control electronics are configured to select an alternative mode of operation to a previously used mode of operation if the measured value for the time interval or duration, respectively, is smaller than a predetermined threshold value, and to maintain the previously used mode if the measured value is greater than the threshold value.

5. The electronic smoking device according to claim 2, wherein the control electronics are configured to utilise a default mode of operation to activate the heater if the measured value for the time interval or duration, respectively, has exceeded a predetermined threshold value.

6. The electronic smoking device according to claim 1, wherein the control electronics are configured to indicate the selection of a specific mode different from the previously used mode by an externally detectable acknowledgment signal.

7. The electronic smoking device according to claim 1, wherein the puff detector is configured to detect an over-pressure and the control electronics are responsive to detection of an over pressure by the puff detector to change the currently selected mode of operation for the heater.

8. The electronic smoking device according to claim 1, wherein the control electronics are configured to store data recording a history of activation of the puff detector and select a mode of operation to be utilised to activate the heater on the basis of the current detected manner of the activation of the puff detector and the stored data recording the history of activation of the puff detector.

9. The electronic smoking device according to claim 8 wherein the control electronics are configured to compare the current detected manner of the activation of the puff detector with one or more thresholds, wherein the thresholds are set on the basis of the stored data recording the history of activation of the puff detector.

10. The electronic smoking device according to claim 9 wherein the thresholds are set on the basis of the stored data recording the history of activation of the puff detector comprise thresholds relating to any of: the duration, frequency or extent of inhalation detected by the puff detector detecting a user sucking on the device.

11. The electronic smoking device according to claim 1, wherein at least one of the predetermined modes of operation is operable to create less aerosol during a puff than at least one of the other predetermined modes of operation.

12. The electronic smoking device according to claim 1, wherein the control electronics are configured to measure the time lapsed after the latest puff and to transfer the electronic smoking device into a dormant state, if this time exceeds a predetermined level.

13. A method for operating an electronic smoking device, comprising: using control electronics of the device for detecting a predetermined sequence of sucking and/or blowing applied to the device by a user, the sequence corresponding to a specific mode of operation of the device; using the control electronics for identifying the specific mode of operation of the device corresponding to the predetermined sequence; and using the control electronics for switching a heater of the device into the specific mode of operation identified, based on the detected predetermined sequence of sucking and/or blowing applied to the device by the user.

14. The electronic smoking device in accordance with claim 13 wherein the reservoir comprises a replaceable reservoir operable to be mounted and demounted from the atomizer.

15. The method of claim 13 wherein the control electronics identifies the specific mode of operation corresponding to the sequence by using a look-up table stored in the control electronics.

16. The electronic smoking device of claim 1 wherein the plurality of modes of operation includes a first mode wherein the atomizer generates a first amount of aerosol per puff, and a second mode wherein the atomizer generates a second amount of aerosol per puff, wherein the second amount is greater than the first amount.

17. A method of controlling an electronic smoking device, comprising: sensing a user sucking on or blowing into the device; detecting a characteristic of the sucking or blowing; selecting a mode of operation from a plurality of modes of operation based on the characteristic detected via the sucking or blowing; operating a heater of an atomizer based on the selected mode of operation, with two or more of the plurality of modes of operation operating the heater generating different volumes of aerosol.

18. The electronic smoking device of claim 1 wherein the mode selection is performed based only on the sucking on or blowing into the device, without using any interface element.

Description

(1) In the following, the invention is further explained by means of embodiments. The drawings show in

(2) FIG. 1 a schematic longitudinal section of an embodiment of the electronic smoking device according to the invention and

(3) FIG. 2 a schematic block diagram illustrating mode selection by means of the puff detector and the control electronics of the electronic smoking device.

(4) FIG. 1 illustrates an embodiment of an electronic smoking device 1 in a schematic longitudinal section.

(5) The electronic smoking device 1 comprises a cylinder-like housing 2 and a mouthpiece 4, which is designed as a detachable cap. Taking off the mouthpiece 4 provides access to a replaceable capsule 6, which serves as a reservoir for a liquid.

(6) The housing 2 accommodates a battery 10. In the embodiment, the battery 10 is designed as a re-chargeable lithium ion battery and may include its own circuitry. The battery 10 is connected, via leads 12 and 13, to control electronics 14, which includes integrated circuits mounted on a printed circuit board 15. The printed circuit board 15 also supports a plurality of light-emitting diodes (LEDs) 16, which are assembled behind respective windows provided in the housing 2 and indicate the current status of the electronic smoking device 1.

(7) A puff detector 18 is connected to the control electronics 14. In the embodiment, the puff detector 18 is designed as an inhalation sensor, which detects the vacuum generated inside the housing 2 when a user inhales at the mouthpiece 4.

(8) An atomizer 20 comprises a heater 22 connected via leads 23 to the control electronics 14. The heater 22 includes a heating wire mounted at a ceramics shell (not shown is in the Figures), which also supports a wick device 24 made of braided metal or sponge-like metal material. A piercing tip 25 at the distant end of the wick device 24 is able to penetrate a membrane 26 used for sealing the capsule 6 so that liquid 28 contained in the capsule 6 can be guided out of the capsule 6 and through the wick device 24 to the area of the heater 22.

(9) At its free end, the mouthpiece 4 comprises an inhalation aperture 30. At the opposite end of the electronic smoking device 1, a charging port 32 is provided which permits re-charging of the battery 10, e.g. via a USB port.

(10) To use the electronic smoking device 1, a consumer inserts a fresh capsule 6 so that its membrane 26 is pierced and liquid is supplied from the capsule 6 via the wick device 24 to the area of the heater 22. When the consumer inhales at the inhalation aperture 30, the puff detector 18 senses the resulting vacuum inside the housing 2 and indicates that to the control electronics 14. In response thereto, the heater 22 is powered so that its heating wire is able to atomize the liquid in its proximity in order to create an aerosol, which is inhaled by the consumer. In the embodiment, the heater 22 remains switched on for a predetermined period of time, which is given by a predetermined mode. This mode for operating the heater in the atomizer can be selected by the consumer (user) via the puff detector 18, as explained in the following.

(11) The heater 22 may be provided in various other forms of direct heating and indirect heating of the liquid, each having advantages. In direct heating designs, the liquid directly contacts the heating element, which may be a wire coil, rod or other heater surface. In indirect heating designs, the liquid contacts a surface heated by a separate heating element, which does not come into direct contact with the liquid. Other types of atomizers or vaporizers may alternatively be used. Various ultrasonic atomizers are effective in creating vapour without heating. For example, an ultrasonic atomizer using a free-running Colpitts oscillator generates high frequency energy in to the range between 800 kHz and 2000 kHz driving a piezoelectric vibrator converting liquid into vapour. Atomizers having electrostatic, electromagnetic or pneumatic elements have also been proposed.

(12) FIG. 2 illustrates the functional relationship for mode selection by means of a is schematic diagram.

(13) The puff detector 18 is arranged in the airflow pathway within the housing 2. In the embodiment, the puff detector 18 senses an under-pressure (vacuum) in relation to the ambient air pressure. Such kind of sensor is already in common use in electronic cigarettes. The puff detector 18 may be an airflow sensor, such as a rocking vane sensor or a Hall element sensor. These may be used in place of the vacuum sensor, as in some designs, airflow is more easily and accurately measured in comparison to vacuum or pressure. Airflow sensors may also have faster response times. The sensor may be designed to allow airflow through or around the sensor, such as with a sensor having an annular shape. Diaphragm and MEMS sensors may similarly be used. Silica gel corrugated membrane sensors have also been proposed for this type of application. These and similar such sensors are available from Micro Pneumatic Logic, Pompano Beach Fla., USA and from Honeywell Microswitch, Freeport, Ill., USA.

(14) Upon actuation of the puff detector 18, i.e. when the pressure drops, a control signal is transmitted to the control electronics 14. The control electronics 14 comprises a timer circuit 40 (preferably a gate timer), which can be a common component of control electronics in electronic cigarettes. The timer circuit 40 generates, from the control signal, a time marking. A controller 42 in the control electronics 14 is programmed to determine the time intervals elapsed between consecutive control signals from the puff detector 18. This is achieved by simply subtracting the time values of two consecutive time markings (readings). In this way, it is possible to obtain the time interval between two consecutive puffs. This time interval is compared with threshold values for, e.g., normal, short and long intervals. If it turns out that the time interval is in a predetermined range for normal intervals, this is interpreted as normal user activity and does not result in a change of mode. If, however, the time interval is in a predetermined range for short intervals or long intervals, this is interpreted as a user demand for selection of a different mode of operating the electronic smoking device. These predetermined ranges are stored in the control electronics 14, e.g. via firmware.

(15) For example, normal smoking consists of puffs having a minimum puff duration and a typical pause between subsequent puffs, e.g. a minimum puff duration of 2 seconds and a minimum pause between puffs of 5 seconds. If the timer arrangement described above records a user's activity falling in these limits, it is assumed that no user command has been given except regular puffing. That means, the heater 22 of the atomizer 20 is activated upon puffing, and the mode of the electronic smoking device is not changed.

(16) However, in the example, if the user takes only a short pause between puffs, then this will be considered as a command for selection of a different one of the predetermined modes, in this case a mode which delivers more aerosol per puff. In the embodiment, the provision of more aerosol is achieved by actuating the heater 22 of the atomizer 20 for a longer (predetermined) time interval per puff.

(17) The user can be given a feedback to acknowledge the recognition of the mode change command. This can be an optical feedback of any kind, e.g. via the LEDs 16. In a more simple form, the atomizer does not produce aerosol on the second puff to indicate that the user command was understood. Other kinds of feedback, like a sound or a vibration, are conceivable as well.

(18) Similarly, if the user takes a rather long pause between puffs, e.g. more than 20 seconds, this will be interpreted as a command for selection of another mode, i.e. a mode which delivers less aerosol per puff, which is achieved by activating the heater of the atomizer for a shorter time interval per puff.

(19) So far, it was assumed that the beginning of each actuation of the puff detector 18 provides a time marking. However, it is also possible to create time markings via the duration of an individual puff so that, e.g., a very short puff may be interpreted as a command to select a different one of the predetermined modes.

(20) Puff intervals of excessive duration, i.e. of more than one minute, may be ignored as this indicates that the user has simply stopped smoking for a while without any intent to provoke a user interaction.

(21) Similarly, if the time lapsed after the latest puff exceeds a predetermined level, the control electronics 14 may transfer the electronic smoking device into a dormant state or switch it completely off in order to save energy.

(22) In another embodiment, the puff detector is able to detect over-pressure, in addition to detecting under-pressure (vacuum), and to initiate a control signal indicating over-pressure upon detection of an over-pressure. In response to that control signal, the control electronics can select a specific predetermined mode. Thus, in such an embodiment, there is no need for analysing the timing sequence of the signals provided by the puff detector in order to find out whether a signal in question is an ordinary demand for an actuation of the atomizer to generate aerosol or whether that signal is a mode selection signal. On the other hand, the puff detector has to be more elaborate. For example, it may comprise a conventional puff detector for sensing under-pressure plus an additional subunit which is able to detect overpressure. As used here, the word puff means the user inhaling on the mouthpiece of the device, or blowing into the mouthpiece of the device.

(23) In an embodiment including a puff detector operable to detect both under pressure and over pressure, the user blows into the electronic smoking device in order to change the mode or to select a specific mode. An analysis of the timing of the blowing events may nevertheless be helpful in order to assign to the blowing events a plurality of options for different modes. When the user inhales at the mouthpiece of the electronic smoking device, an under-pressure is sensed, which causes the control electronics to activate the heater of the atomizer for providing aerosol.

(24) Although in the above description reference has been made to an electronic smoking device operating in a high and a low mode, it will be appreciated that in embodiments of the present invention more than two modes might be available.

(25) Thus for example, in some embodiments, the atomizer may be operated at a greater number of levels of activation (e.g. low, medium and high). In some embodiments an even greater number of activation levels might be provided with a user being able to set the desired activation level by utilizing the device in a way which was detectable by a puff detector 18.

(26) It will be appreciated that the selection of a mode of operation may be more complex than simply setting a level of activation for the heater 22 of an atomizer 20.

(27) Thus for example, the interaction with the puff detector 18, could cause the device to enter a mode where the activation of a heater 18 was to be set on the basis of the duration of one or more immediately previous inhalations. Such a system could better mimic the variation in heating and smoke generation of a conventional cigarette.

(28) So for example, in such a mode, the heating power of the atomizer 20 could be set based on the duration of the latest detected inhalations within a set time period with the power increasing when the puff detector 18 has determined that a user has been sucking on the device for a higher proportion of the most recent period of time under consideration.

(29) From the foregoing, it is evident that the selection of two or more than two predetermined modes for operating the electronic smoking device can be encoded by control signals initiated by the puff detector in many different ways. In all cases, the user does not have to press any buttons, but it is sufficient just to interact via the mouthpiece of the electronic smoking device in order to change or select a mode.