Aerosol-generating device and preheating method thereof

An aerosol-generating device may include a first heater for generating a first aerosol and a second heater for heating a second aerosol-generating substrate, and may significantly increase the initial atomization amount of the aerosol generating device by heating the second heater based on a preheating time of the first heater in a preheating section for increasing the temperatures of the first heater and the second heater.

TECHNICAL FIELD

The present invention relates to an aerosol-generating device and a preheating method thereof, and more particularly, to an aerosol-generating device capable of increasing an amount of aerosol atomized at the beginning of smoking on the aerosol-generating device, and a preheating method thereof.

BACKGROUND ART

Recently, demand for an alternative to traditional cigarettes has increased. For example, there is growing demand for an aerosol-generating device that generates an aerosol by heating an aerosol-generating material in cigarettes or liquid storages rather than by combusting cigarettes.

Such an aerosol-generating device is designed to generate an aerosol by heating a heater according to a user's input, but when a temperature of the heater is not precisely controlled, the amount of atomization generated cannot satisfy the user's expectation.

In particular, in an aerosol-generating device designed to generate mixed aerosols by heating a plurality of aerosol-generating substrates, when any one of the aerosol-generating substrates is liquid, there is a problem that an amount of aerosol atomized is significantly small at the beginning of smoking compared to the later part of smoking, due to high liquid viscosity.

DISCLOSURE

Technical Problem

The technical problem to be solved by the present invention is, in an aerosol-generating device that simultaneously heats a cigarette and a liquid composition, to provide an aerosol-generating device capable of increasing an amount of aerosol atomized at the beginning of the smoking section by preheating a first heater for heating a cigarette and a second heater for heating a liquid composition before a smoking section, and a preheating method thereof.

Another technical problem to be solved by the present invention is to provide an aerosol-generating device capable of reducing power consumption of a second heater by heating the second heater for heating a liquid composition based on a preheating time of a first heater, and a preheating method thereof.

The technical problems of the present disclosure are not limited to the above-described description, and other technical problems may be derived from the embodiments to be described hereinafter.

Advantageous Effects

An aerosol-generating device and a preheating method thereof according to the present invention may increase an amount of aerosol atomized at the beginning of the smoking section by preheating a first heater and a second heater before a smoking section.

In addition, the aerosol-generating device and the preheating method thereof can significantly reduce the total power consumption of the aerosol-generating device, by setting a preheating time of the second heater heating a liquid substrate to be shorter than a preheating time of the first heater heating a solid substrate.

In addition, the aerosol-generating device and the preheating method thereof can prevent a heater coil from being carbonized by not reheating the liquid substrate even if a user's puff is detected after the liquid substrate preheated in a preheating section.

In addition, the aerosol-generating device and the preheating method thereof can prevent carbonization of the heater coil, thereby preventing phenomena such as deterioration of smoking taste and reduction of atomization amount.

BEST MODE

An aerosol-generating device according to an embodiment of the present invention for solving the above technical problem may include a first heater configured to heat a first aerosol-generating substrate such that a first aerosol is generated at a first vaporization temperature; a second heater configured to heat a second aerosol-generating substrate such that a second aerosol is generated at a second vaporization temperature; a battery configured to supply power to the first heater and the second heater; and a controller configured to control power supplied to the first heater and the second heater such that the first and second heaters are preheated in a preheating section and the first heater is maintained at a preset temperature in a smoking section, wherein the controller starts preheating of the second heater after preheating of the first heater starts and before preheating of the first heater is completed in the preheating section.

In addition, the controller may supply first power to the second heater for a first time period starting from a first time point before the preheating of the first heater is completed.

In addition, the controller may supply second power smaller than the first power to the second heater for a second time period starting from a second time point, which is a time point at which the first time has elapsed from the first time point.

In addition, the controller may increase a temperature of the first heater to a first preheating temperature in the preheating section, increase a temperature of the second heater to a second preheating temperature in the preheating section, and then decrease the temperature of the second heater to a third preheating temperature lower than the second preheating temperature.

In addition, the first preheating temperature may be equal to or higher than the first vaporization temperature, and the third preheating temperature may be lower than the second vaporization temperature.

In addition, the aerosol-generating device may further include a substrate sensor unit configured to sense the presence of the first aerosol-generating substrate, wherein the controller may control the aerosol-generating device to enter the preheating section when the substrate sensor unit senses the presence of the first aerosol-generating substrate.

In addition, the aerosol-generating device may further include an input unit configured to receive a user input, wherein the controller may control the aerosol-generating device to enter the preheating section when the input unit receives the user input.

In addition, the aerosol-generating device may further include a puff sensor unit configured to sense a user's puff, wherein the controller may heat the second heater to a first heating temperature equal to or higher than the second vaporization temperature when the user's puff ends or when a preset sensing time elapses after the user's puff is sensed.

In addition, the controller may reduce the temperature of the second heater to a second heating temperature lower than the second vaporization temperature when a preset sensing time has elapsed after the user's puff ends or the user's puff is sensed.

In addition, the controller may control the temperature of the second heater to be maintained at the second heating temperature even when the user's puff is sensed during a preset idle time after reducing the temperature of the second heater from the first heating temperature to the second heating temperature.

In addition, the first aerosol-generating substrate is a solid substrate, and the second aerosol-generating substrate is a liquid substrate.

An aerosol generating device according to another embodiment of the present invention for solving the above technical problem may include entering a preheating section for increasing temperatures of the first heater and the second heater, wherein the first heater is configured to heat a first aerosol-generating substrate such that a first aerosol is generated at a first vaporization temperature, and the second heater is configured to heat a second aerosol-generating substrate such that a second aerosol is generated at a second vaporization temperature; preheating the first heater in the preheating section; and starting preheating of the second heater after preheating of the first heater starts and before the preheating of the first heater is completed, in the preheating section.

In addition, the starting of preheating of the second heater may include supplying first power to the second heater for a first time period starting from a first time point before the preheating of the first heater is completed; and supplying second power smaller than the first power to the second heater for a second time period starting from a second time point, which is a time point at which the first time elapses from the first time point.

In addition, the preheating of the first heater may include increasing the temperature of the first heater to a first preheating temperature equal to or higher than the first vaporization temperature, and the starting of preheating of the second heater may include increasing the temperature of the second heater to a second preheating temperature equal to or higher than the second vaporization temperature, and then reducing the temperature of the second heater to a third preheating temperature lower than the second vaporization temperature.

In addition, the entering of the preheating section may include entering the preheating section when at least one condition of presence of the first aerosol-generating substrate and reception of a user input is satisfied.

MODE FOR INVENTION

With respect to the terms used to describe the various embodiments, general terms which are currently and widely used are selected in consideration of functions of structural elements in the various embodiments of the present disclosure. However, meanings of the terms can be changed according to intention, a judicial precedence, the appearance of new technology, and the like. In addition, in certain cases, a term which is not commonly used can be selected. In such a case, the meaning of the term will be described in detail at the corresponding portion in the description of the present disclosure.

It will be understood that when an element or layer is referred to as being “over,” “above,” “on,” “connected to” or “coupled to” another element or layer, it can be directly over, above, on, connected or coupled to the other element or layer or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly over,” “directly above,” “directly on,” “directly connected to” or “directly coupled to” another element or layer, there are no intervening elements or layers present. Like numerals refer to like elements throughout.

Hereinafter, the present disclosure will now be described more fully with reference to the accompanying drawings, in which exemplary embodiments of the present disclosure are shown such that one of ordinary skill in the art may easily work the present disclosure. The disclosure may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein.

FIGS.1through2are diagrams showing examples in which a cigarette is inserted into an aerosol generating device.

Referring toFIGS.1and2, the aerosol generating device1may include a battery11, a controller12, a heater13and a vaporizer14. Also, the cigarette2may be inserted into an inner space of the aerosol generating device1.

FIGS.1through2illustrate components of the aerosol generating device1, which are related to the present embodiment. Therefore, it will be understood by one of ordinary skill in the art related to the present embodiment that other general-purpose components may be further included in the aerosol generating device1, in addition to the components illustrated inFIGS.1through2.

Also,FIGS.1and2illustrate that the aerosol generating device1includes the heater13. However, according to necessity, the heater13may be omitted.

FIG.1illustrates that the battery11, the controller12, the vaporizer14, and the heater13are arranged in series. Also, FIG. illustrates that the vaporizer14and the heater13are arranged in parallel. However, the internal structure of the aerosol generating device1is not limited to the structures illustrated inFIGS.1through32In other words, according to the design of the aerosol generating device1, the battery11, the controller12, the heater13, and the vaporizer14may be differently arranged.

When the cigarette2is inserted into the aerosol generating device1, the aerosol generating device1may operate the heater13and/or the vaporizer14to generate an aerosol from the cigarette2and/or the vaporizer14. The aerosol generated by the heater13and/or the vaporizer14is delivered to a user by passing through the cigarette2.

As necessary, even when the cigarette2is not inserted into the aerosol generating device1, the aerosol generating device1may heat the heater13.

The battery11may supply power to be used for the aerosol generating device1to operate. For example, the battery11may supply power to heat the heater13or the vaporizer14, and may supply power for operating the controller12. Also, the battery11may supply power for operations of a display, a sensor, a motor, etc. mounted in the aerosol generating device1.

The controller12may generally control operations of the aerosol generating device1. In detail, the controller12may control not only operations of the battery11, the heater13, and the vaporizer14, but also operations of other components included in the aerosol generating device1. Also, the controller12may check a state of each of the components of the aerosol generating device1to determine whether or not the aerosol generating device1is able to operate.

The controller12may include at least one processor. A processor can be implemented as an array of a plurality of logic gates or can be implemented as a combination of a general-purpose microprocessor and a memory in which a program executable in the microprocessor is stored. It will be understood by one of ordinary skill in the art that the processor can be implemented in other forms of hardware.

The heater13may be heated by the power supplied from the battery11. For example, when the cigarette2is inserted into the aerosol generating device1, the heater13may be located outside the cigarette2. Thus, the heated heater13may increase a temperature of an aerosol generating material in the cigarette2.

The heater13may include an electro-resistive heater. For example, the heater13may include an electrically conductive track, and the heater13may be heated when currents flow through the electrically conductive track. However, the heater13is not limited to the example described above and may include all heaters which may be heated to a desired temperature. Here, the desired temperature may be pre-set in the aerosol generating device1or may be set as a temperature desired by a user.

As another example, the heater13may include an induction heater. In detail, the heater13may include an electrically conductive coil for heating a cigarette in an induction heating method, and the cigarette may include a susceptor which may be heated by the induction heater.

For example, the heater13may include a tube-type heating element, a plate-type heating element, a needle-type heating element, or a rod-type heating element, and may heat the inside or the outside of the cigarette2, according to the shape of the heating element.

Also, the aerosol generating device1may include a plurality of heaters13. Here, the plurality of heaters13may be inserted into the cigarette2or may be arranged outside the cigarette2. Also, some of the plurality of heaters13may be inserted into the cigarette2and the others may be arranged outside the cigarette2. In addition, the shape of the heater13is not limited to the shapes illustrated inFIGS.1through2and may include various shapes.

The vaporizer14may generate an aerosol by heating a liquid composition and the generated aerosol may pass through the cigarette2to be delivered to a user. In other words, the aerosol generated via the vaporizer14may move along an air flow passage of the aerosol generating device1and the air flow passage may be configured such that the aerosol generated via the vaporizer14passes through the cigarette2to be delivered to the user.

For example, the vaporizer14may include a liquid storage, a liquid delivery element, and a heating element, but it is not limited thereto. For example, the liquid storage, the liquid delivery element, and the heating element may be included in the aerosol generating device1as independent modules.

The liquid storage may store a liquid composition. For example, the liquid composition may be a liquid including a tobacco-containing material having a volatile tobacco flavor component, or a liquid including a non-tobacco material. The liquid storage may be formed to be attached/detached to/from the vaporizer14or may be formed integrally with the vaporizer14.

For example, the liquid composition may include water, a solvent, ethanol, plant extract, spices, flavorings, or a vitamin mixture. The spices may include menthol, peppermint, spearmint oil, and various fruit-flavored ingredients, but are not limited thereto. The flavorings may include ingredients capable of providing various flavors or tastes to a user. Vitamin mixtures may be a mixture of at least one of vitamin A, vitamin B, vitamin C, and vitamin E, but are not limited thereto. Vitamin mixtures may be a mixture of at least one of vitamin A, vitamin B, vitamin C, and vitamin E, but are not limited thereto.

The liquid delivery element may deliver the liquid composition of the liquid storage to the heating element. For example, the liquid delivery element may be a wick such as cotton fiber, ceramic fiber, glass fiber, or porous ceramic, but is not limited thereto.

The heating element is an element for heating the liquid composition delivered by the liquid delivery element. For example, the heating element may be a metal heating wire, a metal hot plate, a ceramic heater, or the like, but is not limited thereto. In addition, the heating element may include a conductive filament such as nichrome wire and may be positioned as being wound around the liquid delivery element. The heating element may be heated by a current supply and may transfer heat to the liquid composition in contact with the heating element, thereby heating the liquid composition. As a result, aerosol may be generated.

For example, the vaporizer14may be referred to as a cartomizer or an atomizer, but it is not limited thereto.

The aerosol generating device1may further include general-purpose components in addition to the battery11, the controller12, the heater13, and the vaporizer14. For example, the aerosol generating device1may include a display capable of outputting visual information and/or a motor for outputting haptic information. Also, the aerosol generating device1may include at least one sensor (e.g., a puff detecting sensor, a temperature detecting sensor, a cigarette insertion detecting sensor, etc.). Also, the aerosol generating device1may be formed as a structure where, even when the cigarette2is inserted into the aerosol generating device1, external air may be introduced or internal air may be discharged.

Although not illustrated inFIGS.1through2, the aerosol generating device1and an additional cradle may form together a system. For example, the cradle may be used to charge the battery11of the aerosol generating device1. Alternatively, the heater13may be heated when the cradle and the aerosol generating device1are coupled to each other.

The cigarette2may be similar as a general combustive cigarette. For example, the cigarette2may be divided into a first portion including an aerosol generating material and a second portion including a filter, etc. Alternatively, the second portion of the cigarette2may also include an aerosol generating material. For example, an aerosol-generating material made in the form of granules or capsules may be inserted into the second portion.

The entire first portion may be inserted into the aerosol generating device1, and the second portion may be exposed to the outside. Alternatively, only a portion of the first portion may be inserted into the aerosol generating device1, or the entire first portion and a portion of the second portion may be inserted into the aerosol generating device1. The user may puff aerosol while holding the second portion by the mouth of the user. In this case, the aerosol is generated by the external air passing through the first portion, and the generated aerosol passes through the second portion and is delivered to the user's mouth.

For example, the external air may flow into at least one air passage formed in the aerosol generating device1. For example, the opening and closing and/or a size of the air passage formed in the aerosol generating device1may be adjusted by the user. Accordingly, the amount of smoke and a smoking impression may be adjusted by the user. As another example, the external air may flow into the cigarette2through at least one hole formed in a surface of the cigarette2.

Hereinafter, an example of the cigarette2will be described with reference toFIG.3andFIG.4.

FIG.3andFIG.4illustrates an example of a cigarette.

Referring toFIG.3, the cigarette2may include a tobacco rod21and a filter rod22. The first portion21described above with reference toFIGS.1through2may include the tobacco rod, and the second portion may include the filter rod22.

FIG.3illustrates that the filter rod22includes a single segment. However, the filter rod22is not limited thereto. In other words, the filter rod22may include a plurality of segments. For example, the filter rod22may include a first segment configured to cool an aerosol and a second segment configured to filter a certain component included in the aerosol. Also, according to necessity, the filter rod22may further include at least one segment configured to perform other functions.

The cigarette2000may be packaged by at least one wrapper24. The wrapper24may have at least one hole through which external air may be introduced or internal air may be discharged. For example, the cigarette2may be packaged by one wrapper24. As another example, the cigarette2may be double-packaged by at least two wrappers24. For example, the tobacco rod21may be packaged by a first wrapper241, and the filter rod22may be packaged by wrappers242,243,244. Then, the entire cigarette2may be packaged by another wrapper245. When the filter rod22includes a plurality of segments, each segment may be packaged by a separate wrapper242,243,244.

The tobacco rod21may include an aerosol generating material. For example, the aerosol-generating material may include at least one of glycerin, propylene glycol, ethylene glycol, dipropylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, and oleyl alcohol, but it is not limited thereto. Also, the tobacco rod21may include other additives, such as flavors, a wetting agent, and/or organic acid. Also, the tobacco rod21may include a flavored liquid, such as menthol or a moisturizer, which is injected to the tobacco rod21.

The tobacco rod21may be manufactured in various forms. For example, the tobacco rod21may be formed as a sheet or a strand. Also, the tobacco rod21may be formed as a pipe tobacco, which is formed of tiny bits cut from a tobacco sheet. Also, the tobacco rod21may be surrounded by a heat conductive material. For example, the heat-conducting material may be, but is not limited to, a metal foil such as aluminum foil. For example, the heat conductive material surrounding the tobacco rod21may uniformly distribute heat transmitted to the tobacco rod21, and thus, the heat conductivity applied to the tobacco rod may be increased and taste of the tobacco may be improved. Also, the heat conductive material surrounding the tobacco rod21may function as a susceptor heated by the induction heater. Here, although not illustrated in the drawings, the tobacco rod21may further include an additional susceptor, in addition to the heat conductive material surrounding the tobacco rod21.

The filter rod22may include a cellulose acetate filter. Shapes of the filter rod22are not limited. For example, the filter rod22may include a cylinder-type rod or a tube-type rod having a hollow inside. Also, the filter rod22may include a recess-type rod. When the filter rod22includes a plurality of segments, at least one of the plurality of segments may have a different shape.

Also, the filter rod22may include at least one capsule23. Here, the capsule23may generate a flavor or an aerosol. For example, the capsule23may have a configuration in which a liquid containing a flavoring material is wrapped with a film. For example, the capsule23may have a spherical or cylindrical shape, but is not limited thereto.

Referring toFIG.4, the cigarette3may further include a front-end plug33. The front-end plug33may be located on a side of the tobacco rod42, the side not facing the filter rod32. The front-end plug33may prevent the tobacco rod31from being detached and prevent a liquefied aerosol from flowing into the aerosol generating device1(FIGS.1through3) from the tobacco rod31, during smoking.

The filter rod32may include a first segment321and second segment322. Here, the first segment321can correspond to a first segment of a filter rod22ofFIG.3, and the second segment322can correspond to a third segment of a filter rod22ofFIG.3.

The diameter and total length of the cigarette3can correspond to the diameter and total length of the cigarette2ofFIG.4. For example, the length of the front-end plug33may be about 7 mm, the length of the tobacco rod31may be about 15 mm, the length of the first segment321may be about 12 mm, and the length of the second segment322may be about 14 mm, but it is not limited to this.

The cigarette3may be packaged by at least one wrapper35. The wrapper35may have at least one hole through which external air may be introduced or internal air may be discharged. For example, the front-end plug33may be packaged by a first wrapper351, and the tobacco rod31may be packaged by a second wrapper352, and the first segment321may be packaged by a third wrapper321, and the second segment322may be packaged by a fourth wrapper354. Also, the entire cigarette3may be packaged by a fifth wrapper355.

Also, the fifth wrapper355may have at least one hole36. For example, the hole36may be formed in an area surrounding the tobacco rod31, but is not limited thereto. The hole36may serve to transfer heat formed by the heater13shown inFIG.2andFIG.3to the inside of the tobacco rod31.

Also, the second segment322may include at least one capsule34. Here, the capsule34may generate a flavor or an aerosol. For example, the capsule34may have a configuration in which a liquid containing a flavoring material is wrapped with a film. For example, the capsule34may have a spherical or cylindrical shape, but is not limited thereto.

FIG.5is an internal block diagram of an aerosol-generating apparatus according to an embodiment of the present invention.

Referring to the drawings, the aerosol-generating device1according to the embodiment of the present invention may include a controller510, a battery520, a first heater530, a second heater540, a sensor unit550, an output unit560, an input unit570and a memory580.

The controller510may control all of the battery520, the first heater530, the second heater540, the sensor unit550, the output unit560, the input unit570, and the memory580included in the aerosol-generating device1.

The battery520supplies power to the first heater530and the second heater540, and the amount of power supplied to the first heater530and the second heater540may be controlled by the controller510.

The first heater530may generate a first aerosol at a first vaporization temperature by heating a first aerosol-generating substrate. When a current is applied to the first heater530, heat is generated by the specific resistance, and when the first aerosol-generating substrate is heated by the heated first heater530, an aerosol may be generated.

The first heater530may be a component corresponding to the heater13ofFIGS.1to2. In addition, the first aerosol-generating substrate may be the cigarette2ofFIGS.1to2. The first aerosol-generating-substrate may be a solid substrate including nicotine.

The second heater540may generate a second aerosol at a second vaporization temperature by heating a second aerosol-generating substrate. The second heater540may correspond to a heating element provided in the vaporizer14ofFIGS.1and2. In addition, the second aerosol-generating substrate may be a liquid composition stored in the liquid storage unit ofFIGS.1and2. The second aerosol-generating substrate may be a liquid substrate including an aerosol-forming agent.

The second heater540may generate the second aerosol by heating the second aerosol-generating substrate, and the generated second aerosol may pass through the first aerosol-generating substrate and be delivered to a user together with the first aerosol.

The controller510may control power supplied to the first heater530and the second heater540. The controller510may control the battery520to adjust power supplied to the first heater530and the second heater540.

The controller510may control power supplied to the first heater530and the second heater540through a pulse width modulation (PWM) method. To do so, the controller510may include a pulse width modulation module.

The controller510may heat the first heater530and the second heater540by controlling power supplied to the first heater530and the second heater540.

In detail, the controller510may start preheating of the second heater540at a first time point before the preheating of the first heater530is completed, and may supply predetermined power to the second heater540for a first time period. For example, if a preheating time of the first heater530is 30 seconds, the controller510may start preheating the second heater540from 27 second on the time line, which is 3 seconds before the preheating of the first heater530is completed, and supply predetermined power to the first heater530for the next 1 second.

The controller510may control the temperature of the first heater530and the second heater540by controlling the power supplied to the first heater530and the second heater540according to the preheating section and the smoking section described later.

In the preheating section, the controller510may heat the first heater530at or higher than a first vaporization temperature at which the first aerosol is generated, and may heat the second heater540up to a temperature which is close to but lower than a second vaporization temperature at which the second aerosol is generated.

In more detail, the controller510may heat the first heater530to a first temperature at which the first aerosol is generated at the time of completion of preheating. The first temperature may be set in consideration of the vaporization temperature of the first aerosol-generating substrate. For example, the first temperature may be in the range of 240° C. to 250° C.

The controller510may heat the second heater540to a second temperature at which the second aerosol is not generated when preheating is completed. The second temperature may be set in consideration of the vaporization temperature of the second aerosol-generating substrate. For example, the vaporization temperature of the second aerosol-generating substrate may be 210° C. and the second temperature may be in the range of 200° C. to 205° C.

The reason for preheating the temperature of the second heater540to a temperature which is slightly lower than the second vaporization temperature at which the second aerosol is generated is to prevent the second aerosol-generating substrate, which is installed to increase the amount of atomization of the aerosol-generating device1, from generating the second aerosol regardless of a user's puff, and to quickly heat the second aerosol-generating substrate in response to the user's puff.

The controller510may preheat the first heater530for a preset preheating time. Hereinafter, the preheating section and the preheating time of the first heater530may have the same meaning. Depending on the embodiment, the controller510may include a timer for counting the preheating time.

The preheating time of the first heater530may be set in consideration of a time required for the first heater530to reach a temperature at which the first aerosol is generated. The preheating time of the first heater530may be appropriately set according to a heating performance of the first heater530and components of the first aerosol-generating substrate. For example, the preheating time of the first heater530may be 30 seconds.

The controller510may preheat the second heater540based on the preheating time of the first heater530.

The controller510may start preheating of the second heater540before the preheating of the first heater530is completed. Because the second heater540generates a second aerosol by heating the liquid composition absorbed by a liquid delivery means such as a wick, the second heater does not need to be heated from the start of the preheating section, unlike the first heater530that generates the first aerosol by heating a solid substrate such as a cigarette. Accordingly, the controller510may start preheating at a predetermined time before the preheating of the first heater530is completed.

Once preheating of the second heater540has been started, even if the user's puff is detected, the controller510may not supply additional power to the second heater540in addition to the power for preheating the second heater540. This is to prevent coil carbonization due to overheating of the second heater540.

The sensor unit550may include a substrate sensor unit551, a puff sensor unit553, and a temperature sensor unit555.

The substrate sensor unit551may detect whether the first aerosol-generating substrate is present. To do so, the substrate sensor unit may include at least one cigarette sensor. When the first aerosol-generating substrate is the cigarette2ofFIGS.1and2, the substrate sensor unit551may be installed in a cigarette insertion port (not shown) to detect whether the cigarette2is present. Therefore, the substrate sensor unit551may be referred to as a cigarette sensor unit.

When the substrate sensor unit551detects the first aerosol-generating substrate, a substrate sensing signal may be transmitted to the controller510. On receiving the substrate sensing signal, the controller510may start preheating the first heater530. In addition, the controller510may start preheating the second heater540based on the preheating time of the first heater530.

The puff sensor unit553may detect a user's puff. To do so, the puff sensor unit553may include at least one pressure sensor.

When the pressure inside the aerosol-generating device1is less than or equal to the reference pressure, the puff sensor unit553may transmit a puff sensing signal to the controller510. The controller510may heat the second heater540in response to the puff sensing signal.

The temperature sensor unit555may be installed on the first heater530and the second heater540, and may sense the temperature of the first heater530and the second heater540. To do so, the temperature sensor unit555may include a temperature sensor. For example, the temperature sensor unit555may sense a change in thermal resistance of the first heater530and the second heater540.

The temperature senor555may transmit a temperature sensing signal to the controller510. The controller510may identify the temperatures of the first heater530and the second heater540based on the temperature sensing signal. The controller510may calculate the heating timing, heating duration, and power for the first heater530and the second heater540, based on the temperatures of the first heater530and the second heater540.

The output unit560may output visual information and/or tactile information related to the aerosol-generating device1.

The input unit570may receive a user input. For example, the input unit570may be provided in the form of a push button.

The input unit570may receive on/off commands of the aerosol-generating device1. On receiving an operation command of the aerosol-generating device1, the input unit570may transmit a control signal corresponding to the operation command to the controller510. On receiving the control signal, the controller510may start preheating the first heater530. Also, the controller510may preheat the second heater540based on the preheating time of the first heater530.

The memory580may store information for the operation of the aerosol-generating device1. For example, the memory580may store a temperature profile for the controller510to control the power supplied to the first heater530and the second heater540such that the aerosol-generating device1provides various tastes of the aerosol to a user. The temperature profile may include information such as a preheating timing, a preheating duration, and a preheating temperature of the first heater530and the second heater540.

FIG.6is a graph for explaining a preheating method of an aerosol-generating device according to a first embodiment of the present invention.

Referring toFIG.6, the graph shows the temperature610of the first heater530and the temperature630of the second heater540, according to an embodiment.

When the input unit570receives a user's operation command and/or when the substrate sensor unit551senses the first aerosol-generating substrate, the controller510may control the aerosol-generating device1to enter the preheating section and start preheating of the first heater530.

In detail, when the input unit570receives a user's operation command and/or when the substrate sensor unit551senses the first aerosol-generating substrate, the controller510may start preheating of the first heater530. The controller510may heat the first heater530for a preset preheating time. For example, the preheating time may be 30 seconds. The controller510may control the battery520to supply power to the first heater530for a preset preheating time.

The control unit510may increase the temperature of the first heater530to a first preheating temperature Tp1in the preheating section. The first preheating temperature Tp1may be higher than or equal to a first vaporization temperature at which the first aerosol is generated. For example, the first preheating temperature Tp1may be 240° C., which is the first vaporization temperature. Accordingly, the aerosol-generating device1may provide a user with a rich smoking taste from the beginning of the smoking section.

The controller510may calculate a preheat start timing of the second heater540based on the preheat time of the first heater530. The controller510may start preheating of the second heater540at a predetermined time before the preheating of the first heater530is completed. The reason why the controller510does not heat the second heater540at the same time at the start of the preheating section is that, compared to the first heater530that heats a solid substrate such as a cigarette, the second heater540heats the liquid composition absorbed in the wick which quickly reaches a target preheating temperature.

In detail, the controller510may start preheating of the second heater540at a first time point p1before the preheating of the first heater530is completed at a time point p3. The controller510may supply first power to the second heater540for a first time t1from the time point p1which is the start time of preheating of the second heater540. For example, when the preheating time of the first heater530is 30 seconds, the controller510may start preheating of the second heater540at 27 second on the timeline, which is 3 seconds before the preheating of the first heater530is completed at the third time point p3. Also, for example, the controller510may supply the first power to the second heater540for the next 1 second (i.e., the first time t1may be 1 second).

As the controller510supplies the first power to the second heater540for the first time t1, the temperature630of the second heater540may increase to the second preheating temperature Tp2at a second time point p2(i.e., when the first time t1has passed from the first time point p1). In other words, the controller510may start preheating the second heater540at the first time point p1and increase the temperature630of the second heater540to the second preheating temperature Tp2at the second time point p2. The second preheating temperature Tp2may be greater than the second vaporization temperature at which the second aerosol is generated. For example, the second preheating temperature Tp2may be 280° C.

The controller510may supply second power less than the first power to the second heater540for a second time t2between the second time point p2(i.e., when the first time t1has passed from the first time point p1) and the third time point p3at which the preheating section ends. For example, assuming that the preheating time of the first heater530is 30 seconds and the controller510heats the second heater540for 1 second starting from 27 second on the time line, the controller510may supply second power smaller than the first power to the second heater540from 28 second to 30 second on the timeline.

As the controller510supplies the second power to the second heater540for the second time t2, the temperature of the second heater540may be reduced to a third preheating temperature Tp3lower than the second preheating temperature Tp2at a third time point p3which is a time point when the preheating ends (i.e., when the second time t2has passed from the second time point p2). In other words, the controller510may reduce the temperature630of the second heater540to the third preheating temperature Tp3lower than the second preheating temperature Tp2by controlling the power supplied to the second heater540at the second time point p2. The third preheating temperature Tp3is lower than the second vaporization temperature at which the second aerosol is generated, but may be a temperature close to the second vaporization temperature. For example, the second vaporization temperature of the second aerosol-generating substrate may be 210° C., and the third preheating temperature Tp3may be 205° C.

The reason for preheating the temperature of the second heater540to a temperature close to but lower than the second vaporization temperature at which the second aerosol is generated is to prevent the second aerosol-generating substrate, which is installed to increase the amount of atomization, from generating the second aerosol regardless of the user's puff, and to rapidly heat the second aerosol-generating substrate in response to the user's puff.

After the second time point p2, the controller510may not supply additional power to the second heater540for the second time t2even when a puff of the user is sensed. This is to prevent coil carbonization due to overheating of the second heater540. For example, the second time t2may be 2 seconds.

As described above, according to an embodiment, by separately providing a preheating section before the smoking section, it is possible to reduce the liquid viscosity immediately before the smoking section to a level at which vaporization may quickly occur. Accordingly, there is an advantage that the amount of atomization at the beginning of smoking may be remarkably increased by increasing the moving speed of the liquid composition through the wick. As such, user satisfaction may be increased.

As described above, in the first embodiment of the present invention, unlike the second and third embodiments to be described later, the second heater540may be rapidly heated to the second preheating temperature Tp2and then reduced to the third preheating temperature Tp3which is a temperature close to but lower than the vaporization temperature of the second aerosol-generating substrate. This has the advantage of rapidly preheating the second heater540to a temperature close to the vaporization temperature of the second aerosol-generating substrate and reducing power consumption of the aerosol-generating device1.

Meanwhile, in the smoking section (i.e., after the third time point p3), the controller510may maintain the temperature610of the first heater530equal or higher than the first vaporization temperature at which the first aerosol is generated, and heat the second heater540in response to the user's puff.

In detail, the controller510may control the temperature610of the first heater530to be maintained at the first preheating temperature Tp1in the smoking section. For example, the controller510may control the temperature610of the first heater530through a proportional integral difference (PID) control method, but the present invention is not limited thereto.

The controller510may increase the temperature630of the second heater540when the puff sensor unit553senses a user's puff while the second heater540is at a third preheating temperature Tp3and the second aerosol is not generated.

The controller510may supply a third power less than the first power but greater than the second power to the second heater540for the third time t3from the fourth time point p4, which is the user's puff start time. Also, the controller510may maintain supply of the third power for the fourth time t4. The sum of the third time t3and the fourth time t4may be greater than the first time t1. This is to ensure a sufficient amount of atomization when the user puffs. For example, the sum of the third time t3and the fourth time t4may be 2 seconds.

As the controller510supplies third power to the second heater540, when the third time t3has passed from the fourth time point p4, the temperature of the second heater540may be increased to a preset first heating temperature Th1which is greater than or equal to the second vaporization temperature at which the second aerosol is generated. Also, the first heating temperature Th1of the second heater540may be maintained for a fourth time t4. As the first heating temperature Th1is maintained for the fourth time t4, a sufficient amount of atomization may be generated when the user puffs.

The controller510may supply second power to the second heater540for a fifth time t5after the fourth time t4expires. As the controller510supplies the second power for the fifth time t5, the temperature of the second heater540may be reduced to the second heating temperature Th2. As shown inFIG.6, the second heating temperature Th2may be the same as the third preheating temperature Tp3. By setting the second heating temperature Th2in the smoking section to be the same as the third preheating temperature Tp3in the preheating section, convenience of control may be improved.

On the other hand, when the temperature of the second heater540is reduced from the first heating temperature Th1to the second heating temperature Th2(i.e., Tp3), the controller510may control the temperature630of the second heater540to be maintained at the second heating temperature Th2during a preset idle time, even when the puff sensor unit553senses the user's puff. InFIG.6, the idle time may be a fifth time t5. The fifth time t5may be less than the second time t2. For example, the idle time may be 1 second. This is to prevent coil carbonization due to overheating of the second heater540.

FIG.7is a graph for explaining a preheating method of an aerosol-generating device according to a second embodiment of the present invention.

The difference fromFIG.6is that the temperature730of the second heater540is gradually increased to a target preheating temperature in the preheating section.

Referring toFIG.6, the controller510may start preheating of the second heater540at a first time point p1before preheating of the first heater530is completed. The controller510may supply the fourth power to the second heater540for the first time t1after starting preheating of the second heater540. The first time t1ofFIG.7may be greater than the first time t1ofFIG.6. For example, when the preheating time of the first heater530is 30 seconds, the controller510may start preheating of the second heater540at 10 second on the timeline, which is 20 seconds before the completion of preheating of the first heater530, and may supply fourth power to the second heater540for the next 18 seconds.

As the controller510supplies the fourth power to the second heater540for the first time t1, the temperature730of the second heater540may increase to a fourth preheating temperature Tp4at a second time point p2(i.e., when the first time t1has passed from the first time point P1). In other words, the controller510may start preheating of the second heater540at the first time point p1, and increase the temperature730of the second heater540to the fourth preheating temperature Tp4at the second time point p2. The fourth preheating temperature Tp4ofFIG.7may be the same as the third preheating temperature Tp3ofFIG.6. Also, the fourth preheating temperature Tp4may be slightly lower than the second vaporization temperature at which the second aerosol is generated. For example, the second vaporization temperature of the second aerosol-generating substrate may be 210° C., and the fourth preheating temperature Tp4may be 205° C.

The controller510may control the temperature730of the second heater540to be maintained at the fourth preheating temperature Tp4for the second time t2which is between the second time point p2(i.e., when the first time t1has passed from the first time point p1) and the third time point p3at which the preheating section ends. For example, assuming that the preheating time of the first heater530is 30 seconds and the controller510heats the second heater540for 18 seconds starting from 10 second on the timeline, the controller510may maintain the temperature730of the second heater540at the fourth preheating temperature Tp4from 28 second to 30 second on the timeline.

After the second time point p2, the controller510does not supply additional power to the second heater540for the second time t2to maintain the temperature730, even when a puff of the user is sensed. This is to prevent coil carbonization due to overheating of the second heater540as inFIG.6. For example, the second time t2may be 2 seconds.

The preheating method of the aerosol-generating device1according to the second embodiment of the present invention may prevent the durability of the second heater540from being degraded due to rapid heating, by starting the preheating of the second heater540earlier than the first embodiment and gradually increasing the temperature730of the second heater540.

FIG.8is a graph for explaining a preheating method of an aerosol-generating device according to a third embodiment of the present invention.

The difference fromFIGS.6and7is that the temperature of the second heater540is increased in a stepwise manner to a target preheating temperature in the preheating section.

Referring toFIG.8, the controller510may start preheating of the second heater540at a first time point p1before preheating of the first heater530is completed at a time point p3. The controller510may gradually increase the power supplied to the second heater540step by step for the first time t1, after preheating the second heater540is started at the first time point p1. The first time t1ofFIG.8may be greater than the first time t1ofFIG.6and less than the first time t1ofFIG.7. For example, assuming that the preheating time of the first heater530is 30 seconds, the controller510may start preheating the second heater540at 13 second on the timeline, which is 17 seconds before the preheating of the first heater530is completed, and increase the power supplied to the second heater540step by step for the next 15 seconds.

The controller510may supply a fifth power to the second heater540for a fifth time t5after preheating of the second heater540is started at the first time point p1. For example, the fifth time t5may be 1 second. As will be described later, by setting the initial heating time to be short, the second heater540may quickly reach the preheating temperature of the second aerosol-generating substrate.

As the controller510supplies the fifth power to the second heater540for the fifth time t5, the temperature830of the second heater540may increase to the fifth preheating temperature Tp5.

The controller510may prevent a rapid temperature change of the second heater540by maintaining the temperature830of the second heater540at the fifth preheating temperature Tp5for a sixth time t6after the fifth time t5expires.

Similarly, the controller510may supply a sixth power to the second heater540for a seventh time t7to increase the temperature830of the second heater540to a sixth preheating temperature Tp6, and may maintain the temperature830of the second heater540at the sixth preheating temperature Tp6for the eighth time t8after the seventh time t7expires.

Also, the controller510may increase the temperature830of the second heater540to a seventh preheating temperature Tp7by supplying a seventh power to the second heater540for a ninth time t9. The seventh preheating temperature Tp7may be the same as the third preheating temperature Tp3ofFIG.6. The seventh preheating temperature Tp7may be slightly lower than the second vaporization temperature at which the second aerosol is generated. For example, the vaporization temperature of the second aerosol-generating substrate may be 210° C., and the seventh preheating temperature Tp7may be 205° C.

The controller510may maintain the temperature830of the second heater540at the seventh preheating temperature Tp7for a second time t2between the second time point p2(i.e., when the first time t1has passed from the first time point p1) and the third time point p3(i.e., when the preheating section terminates). For example, assuming that the preheating time of the first heater530is 30 seconds and the controller510heats the second heater540for 15 seconds starting from 13 second on the timeline, the controller510may maintain the temperature830of the second heater540at the seventh preheating temperature Tp7from 28 second to 30 second on the timeline.

As shown inFIGS.6to7, in order to prevent coil carbonization due to overheating of the second heater540, the controller510may not supply additional power to the second heater540for the second time T2such that the temperature830of the second heater540is maintained at the seventh preheating temperature Tp7, even when a puff of the user is sensed.

The preheating method of the aerosol-generating device1according to the third embodiment of the present invention may prevent the durability of the second heater540from being degraded due to rapid heating, by starting the preheating of the second heater540earlier than the first embodiment and gradually increasing the temperature830of the second heater540step by step.

In addition, the preheating method of the aerosol-generating device1according to the third embodiment provides an advantage in terms of power consumption by starting the preheating of the second heater540later than the second embodiment.

FIG.9is a flowchart illustrating a preheating method of an aerosol-generating device according to an embodiment of the present invention.

Referring to theFIG.9, when the input unit570receives a user's operation command and/or when the substrate sensor unit551senses a first aerosol-generating substrate, the controller510may control the aerosol-generating device to enter the preheating section (S910).

The controller510may start preheating of the first heater530in the preheating section (S920). As described above with reference toFIGS.6-8, the controller510may increase the temperature of the first heater530to the first preheating temperature Tp1in the preheating section. The first preheating temperature Tp1may be higher than or equal to the first vaporization temperature at which the first aerosol is generated. Accordingly, the present invention may provide a user with a rich smoking taste from the beginning of the smoking section.

The controller510may start preheating of the second heater540before the preheating of the first heater530is completed (S930). The controller510may heat the second heater540to a target preheating temperature at which the second aerosol is not yet generated.

In more detail, the controller510may calculate a preheat start time of the second heater540based on the preheat time of the first heater530. As described above with reference toFIGS.6-8, the controller510may start preheating of the second heater540at a first time point p1before the preheating of the first heater is completed.

The controller510may supply a predetermined power to the second heater540during the preheating period after preheating the second heater540is started.

According to the first embodiment shown inFIG.6, the controller510may supply the first power to the second heater540for a first time t1after preheating the second heater540is started at a time point p1.

As the first power is supplied to the second heater540for the first time t1, the temperature630of the second heater540may increase to the second preheating temperature Tp2at a second time point p2(i.e., when the first time t1has passed from the first time point p1). The second preheating temperature Tp2may be greater than the second vaporization temperature at which the second aerosol is generated.

The controller510may supply second power smaller than the first power to the second heater540for a second time t2between the second time point p2when the first time t1has passed from the first time point p1and the time point p3at which the preheating section ends.

As the controller510supplies the second power to the second heater540for the second time t2, the temperature630of the second heater540may be reduced to a third preheating temperature Tp3lower than the second preheating temperature Tp2at a third time point p3(i.e., when the second time t2has passed from the second time point p2). The third preheating temperature Tp3may be a target preheating temperature.

According to the second embodiment shown inFIG.7, the controller510may start preheating of the second heater540at a time earlier than the start of preheating of the aerosol-generating device1according to the first embodiment.

The controller510may supply the fourth power to the second heater540for the first time t1after preheating the second heater540is started at the time point p1.

As the controller510may supply the fourth power to the second heater540for the first time t1, the temperature730of the second heater540may increase to the fourth preheating temperature Tp4at a second time point p2at the time point p3(i.e., when the first time t1has passed from the first time point p1).

The controller510may maintain the temperature730of the second heater540at the fourth preheating temperature Tp4for a second time t2which is between the time point p2and the third time point p3at which the preheating section ends. The fourth preheating temperature Tp5may be a target preheating temperature.

According to the third embodiment shown inFIG.8, the controller510may start preheating of the second heater540at a time point earlier than the start of preheating of the aerosol-generating device1according to the first embodiment, but at a time point later than the start of preheating of the aerosol-generating device1according to the second embodiment.

The controller510may gradually increase the power supplied to the second heater540step by step for the first time t1after preheating the second heater540is started at the first time point p1.

As the controller510gradually increases the power supplied to the second heater540step by step for the first time t1, the temperature830of the second heater540may increase to the seventh preheating temperature Tp7at a second time point p2(i.e., when the first time t1has passed from the first time point p1).

The controller510may maintain the temperature830of the second heater540at the seventh preheating temperature Tp7for a second time t2from the second time point p2to the third time point p3at which the preheating section ends. The seventh preheating temperature Tp7may be a target preheating temperature.

The above-described method may be written in a program that may be executed on a computer, and may be implemented in a general-purpose digital computer that operates the program using a computer-readable recording medium. In addition, the structure of the data used in the above-described method may be recorded on a computer-readable recording medium through various means. The computer-readable recording medium includes storage media such as magnetic storage media (e.g., ROM, RAM, USB, floppy disk, hard disk, etc.), optical reading media (e.g., CD-ROM, DVD, etc.).

Those of ordinary skill in the art related to the present embodiments may understand that various changes in form and details can be made therein without departing from the scope of the characteristics described above. The disclosed methods should be considered in a descriptive sense only and not for purposes of limitation. The scope of the present invention is shown in the claims rather than the foregoing description, and all differences within the scope equivalent thereto should be construed as being included in the present invention.