EP4602939A1

EP4602939A1 - Aerosol generation device

Info

Publication number: EP4602939A1
Application number: EP22964407.5A
Authority: EP
Inventors: Ryuji Sakai
Original assignee: Japan Tobacco Inc
Current assignee: Japan Tobacco Inc
Priority date: 2022-11-02
Filing date: 2022-11-02
Publication date: 2025-08-20
Also published as: JPWO2024095387A1; WO2024095387A1

Abstract

[Problem] To provide an aerosol generation device with an enhanced waterproof property.[Solution] Provided is an aerosol generation device that comprises: a holding portion that has a cylindrical structure into which an aerosol-generating base material is inserted; a body portion provided on a bottom surface of the cylindrical structure; a gap formed in the bottom surface along the outline of the body portion; and a convex portion protruding from the body portion to cover an opening of the gap.

Description

[Technical Field]

The present invention relates to an aerosol generating device.

[Background Art]

Inhalation devices such as e-cigarettes and nebulizers that generate substances to be inhaled by a user are in widespread use. Inhalation devices are capable of generating an aerosol by heating an aerosol source. This allows the user to inhale the aerosol generated by the inhalation device to enjoy the flavor of the aerosol.
In inhalation devices such as these, liquid drops may be formed inside the inhalation device due to a build up of the aerosol generated from the aerosol source. PTL 1 below indicates that a gap inside a tube accommodating the aerosol source is closed off by a sealing member in order to prevent faults in circuits, etc. caused by the liquid drops formed.

[Citation List]

[Patent Literature]

[PTL 1] JP 2020-188794 A

[Summary of Invention]

[Technical Problem]

However, the technology disclosed in PTL 1 above is intended to prevent permeation of small amounts of moisture, such as liquid drops, into the gap, but does not envisage a situation in which a large amount of water pours into a holding portion accommodating the aerosol source, such as when the holding portion is rinsed with water. Consequently, there is also a need to suppress penetration of water into the device when a large amount of water pours into the holding portion accommodating the aerosol source.
Accordingly, the present invention was devised in light of the problem above, and the objective of the present invention lies in providing a novel and improved aerosol generating device capable of further improving waterproofing.

[Solution to Problem]

In order to solve the problem above, one aspect of the present invention provides an aerosol generating device comprising: a holding portion having a cylindrical structure inside which an aerosol generating substrate is inserted; a main body portion provided on a bottom face of the cylindrical structure; a gap formed in the bottom face along an outer shape of the main body portion; and a projection protruding from the main body portion so as to cover an opening of the gap.
The projection may protrude so that the width of the opening after being covered is 0.2 mm or less.
At least a surface of the projection may be formed from a water-repellent material.
The projection may be formed from a silicone resin material, a fluororesin material, or a ceramic material.
The projection may be provided so that the height of a tip end of the projection is no less than the height of any point between the center of the main body portion and the projection.
The gap may be sealed by a sealing member provided inside the gap.
A counter projection which is provided on a surface facing the projection and overlaps the projection may further be provided.
The gap may be provided between the main body portion and a casing for holding the main body portion from the outside.
The gap may be provided between the main body portion and a heating unit for heating the aerosol generating substrate while protruding into the cylindrical structure from the bottom face.

[Advantageous Effects of Invention]

The present invention as described above makes it possible to further improve waterproofing of an aerosol generating device.

[Brief Description of Drawings]

[Fig. 1] is a schematic diagram schematically showing a configuration example of an inhalation device.
[Fig. 2] is a schematic view in cross section showing a first configuration example of a bottom portion of a holding portion.
[Fig. 3] is an illustrative diagram schematically showing an example of the cross-sectional shape of a projection.
[Fig. 4] is an illustrative diagram schematically showing an example of the cross-sectional shape of the projection.
[Fig. 5] is an illustrative diagram schematically showing an example of the cross-sectional shape of the projection.
[Fig. 6] is an illustrative diagram schematically showing an example of the cross-sectional shape of the projection.
[Fig. 7] is a schematic view in cross section showing a variant example in which a plurality of projections protrude from a first fixing portion.
[Fig. 8] is a schematic view in cross section showing a variant example in which a plurality of projections protrude from the first fixing portion, and a counter projection protrudes from a casing.
[Fig. 9] is a schematic view in cross section showing a second configuration example of the bottom portion of the holding portion.
[Fig. 10] is a schematic diagram showing a model for deriving the amount of water flowing through a gap when no projection is provided.
[Fig. 11] is a schematic diagram showing a model for deriving the amount of water flowing through a gap when a projection is provided.

[Description of Embodiments]

Preferred embodiments of the present invention will be described in detail below with reference to the appended drawings. It should be noted that components having substantially the same functional configuration will be assigned the same reference numbers in the description and drawings to avoid giving a duplicate description.

<1. Configuration example of inhalation device>

A configuration example of an inhalation device according to an embodiment of the present invention will be described first of all. The inhalation device according to this configuration example is capable of generating an aerosol by heating a substrate that contains an aerosol source from inside the substrate. This configuration example will be described below with reference to fig. 1.
Fig. 1 is a schematic diagram illustrating schematically a configuration example of an inhalation device. As shown in fig. 1, an inhalation device 100 according to this configuration example comprises a power source unit 111, a sensor unit 112, a notification unit 113, a memory unit 114, a communication unit 115, a control unit 116, a heating unit 121, and a holding portion 140. A user inhales with the inhalation device 100 in a state in which a stick-type substrate 150 is accommodated in a holding portion 140. The components will be described in order below.
It should be noted that the inhalation device 100 and the stick-type substrate 150 cooperate to generate an aerosol to be inhaled by the user. As such, the combination of the inhalation device 100 and the stick-type substrate 150 may be considered to be an aerosol generation system.
The power source unit 111 stores electrical power. The power source unit 111 then supplies electrical power to each component of the inhalation device 100. The power source unit 111 may be configured by a rechargeable battery such as a lithium ion secondary battery, for example. The power source unit 111 may be charged by being connected to an external power source by means of a USB (universal serial bus) cable or the like. Furthermore, the power source unit 111 may also be charged by means of wireless power transmission technology, without being connected to a power transmission-side device. Additionally, the power source unit 111 may be provided so as to be removable from the inhalation device 100, and may be provided so as to be replaceable with a new power source unit 111.
The sensor unit 112 detects various types of information relating to the inhalation device 100 and outputs the detected information to the control unit 116. As an example, the sensor unit 112 is configured by a pressure sensor such as a capacitor microphone, a flow rate sensor or a temperature sensor. In this way, when the sensor unit 112 has detected a numerical value associated with inhalation by a user, the sensor unit 120 may then output, to the control unit 116, information indicating that the user has inhaled. As another example, the sensor unit 112 may be configured by an input device, such as a button or switch, for receiving input of information from the user. The sensor unit 112 may especially comprise a button for instructing starting/stopping of aerosol generation. In this way, the sensor unit 112 may output to the control unit 116 the information input by the user. As a further example, the sensor unit 112 may be configured by a temperature sensor for detecting the temperature of the heating unit 121. In this way, the sensor unit 112 may determine the temperature of the stick-type substrate 150 accommodated in the holding portion 140 by detecting the temperature of the heating unit 121 on the basis of an electrical resistance value of the heating unit 121, for example.
The notification unit 113 notifies the user of the information. As an example, the notification unit 113 is configured by a light-emitting device such as an LED (light-emitting diode). In this way, when the power source unit 111 is in a state of requiring charging, when the power source unit 111 is in the process of charging, or when an abnormality has occurred in the inhalation device 100, etc., the notification unit 113 may emit light in a different light emission pattern for each case. The light emission patterns as referred to here generally include colors and timing of illumination/extinguishing. Instead of or as well as the light-emitting device, the notification unit 113 may also be configured by a display device for displaying images, a sound output device for outputting sounds, or a vibration device which vibrates, etc. Additionally, the notification unit 113 may notify information indicating that inhalation by the user is possible. The information indicating that inhalation by the user is possible may be notified when the temperature of the stick-type substrate 150 heated by means of the heating unit 121 has reached a predetermined temperature.
The memory unit 114 stores various types of information for the operation of the inhalation device 100. The memory unit 114 is configured by a non-volatile storage medium such as a flash memory, for example. Information relating to the operating system (OS) of the inhalation device 100, such as information relating to control performed by the control unit 116 of various types of components, is an example of the information stored in the memory unit 114. Another example of the information stored in the memory unit 114 is information relating to inhalation by the user, such as number of inhalations, times of inhalation, or cumulative inhalation time.
The communication unit 115 is a communication interface for sending and receiving information between the inhalation device 100 and another device. The communication unit 115 performs communication conforming to any wired or wireless communication standard. Examples of communication standards which may be used include wireless LAN (local area network), wired LAN, Wi-Fi (registered trademark), and Bluetooth (registered trademark), etc. As one example, the communication unit 115 may send information relating to inhalation by the user to a smartphone in order to cause the smartphone to display the information relating to inhalation by the user. As another example, the communication unit 115 may receive new OS information from a server in order to update the OS information stored in the memory unit 114.
The control unit 116 functions as an arithmetic processing device and a control device, and controls overall operation within the inhalation device 100 in accordance with various programs. The control unit 116 is realized by a CPU (central processing unit) or an electronic circuit such as a microprocessor, for example. The control unit 116 may also include a ROM (read-only memory) for storing programs and computation parameters, etc. which are used, and a RAM (random access memory) for temporarily storing suitably changing parameters, etc. The inhalation device 100 implements various types of processing on the basis of control performed by the control unit 116. Examples of processing controlled by the control unit 116 include: supply of electricity from the power source unit 111 to other components; charging of the power source unit 111; detection of information by the sensor unit 112; notification of information by the notification unit 113; storage and reading of information by the memory unit 114; and sending/receiving of information by the communication unit 115. Other processing implemented by the inhalation device 100, such as processing based on input of information to each component and information output from each component, are also controlled by means of the control unit 116.
The holding portion 140 has an internal space 141, and holds the stick-type substrate 150 while accommodating a portion of the stick-type substrate 150 in the internal space 141. The holding portion 140 has an opening 142 allowing the internal space 141 to communicate with the outside, and holds the stick-type substrate 150 which has been inserted into the internal space 141 from the opening 142. For example, the holding portion 140 is a cylindrical body comprising the opening 142 and a bottom portion 143 serving as a bottom surface, and defines a columnar internal space 141. The holding portion 140 is configured so that the inner diameter of at least part of the cylindrical body in a height direction is smaller than the outer diameter of the stick-type substrate 150, and is capable of holding the stick-type substrate 150, which has been inserted into the internal space 141, so as to press the stick-type substrate 150 from the outer circumference thereof. The holding portion 140 also has a function for defining a flow path for air passing through the stick-type substrate 150. An air inflow hole which is an inlet for air into the flow path is disposed in the bottom portion 143, for example. Meanwhile, the opening 142 forms an air outflow hole, which is an outlet for air from the flow path.
The stick-type substrate 150 is a substrate in the shape of a stick which generates an aerosol. The stick-type substrate 150 comprises a substrate portion 151 and a mouthpiece portion 152.
The substrate portion 151 comprises an aerosol source. The aerosol source is atomized by heating so as to generate an aerosol. The aerosol source may be, for example, a tobacco-derived material such as shredded tobacco, or a processed product obtained by molding a tobacco raw material into a granular form, a sheet form, or a powder form. Furthermore, the aerosol source may also contain a non-tobacco-derived substance produced from a plant other than tobacco (e.g., mint or herb, etc.). When the inhalation device 100 is a medical inhaler, the aerosol source may contain a drug to be inhaled by a patient. It should be noted that the aerosol source is not limited to a solid, and may equally be a polyhydric alcohol such as glycerol or propylene glycol, or may be a liquid such as water, for example. In a state in which the stick-type substrate 150 is being held in the holding portion 140, at least part of the substrate portion 151 is accommodated in the internal space 141 of the holding portion 140.
The mouthpiece portion 152 is a member which is held in the user's mouth during inhalation. In a state in which the stick-type substrate 150 is being held in the holding portion 140, at least part of the mouthpiece portion 152 protrudes from the opening 142. When the user then inhales with the mouthpiece portion 152, which protrudes from the opening 142, held in the mouth, air flows into the holding portion 140 from the air inflow hole which is not depicted. The air which has flowed in passes through the internal space 141 of the holding portion 140, that is, through the substrate portion 151, and reaches the user's mouth together with the aerosol generated from the substrate portion 151.
The heating unit 121 heats the aerosol source and thereby atomizes the aerosol source to generate an aerosol. The heating unit 121 has a blade-like form and is arranged so as to protrude into the internal space 141 from the bottom portion 143 of the holding portion 140. When the stick-type substrate 150 is inserted into the holding portion 140, the blade-like heating unit 121 therefore pierces the substrate portion 151 of the stick-type substrate 150 and is inserted inside the stick-type substrate 150. When the heating unit 121 generates heat, the aerosol source contained in the stick-type substrate 150 is then heated from the inside of the stick-type substrate 150 and atomized, generating the aerosol. The heating unit 121 generates heat when supplied with electricity from the power source unit 111. As an example, when the sensor unit 112 has detected that there has been predetermined user input, the heating unit 121, which has been supplied with power, generates heat, and an aerosol is generated from the stick-type substrate 150 as a result of the temperature of the stick-type substrate 150 reaching a predetermined temperature. By this means, the inhalation device 100 is capable of enabling inhalation by the user. After this, the electrical supply to the heating unit 121 may be stopped when the sensor unit 112 has detected that there has been predetermined user input. As another example, the aerosol may be generated by the heating unit 121, which has been supplied with power, during a period in which the sensor unit 112 detects that there is inhalation by the user.
In the inhalation device 100 according to this embodiment, a projection is provided so as to cover a gap formed in the bottom portion 143 of the holding portion 140, thereby making it possible to suppress an inflow of water, which has poured into the internal space 141 of the holding portion 140, to the gap. The structure of the bottom portion 143 of this holding portion 140 will be described in detail below.

<2. Structure of bottom portion of holding portion>

(2.1. First configuration example)

A first configuration example of the bottom portion 143 of the holding portion 140 will be described with reference to fig. 2. Fig. 2 is a schematic view in cross section showing the first configuration example of the bottom portion 143 of the holding portion 140.
As shown in fig. 2, a main body portion 160 is provided at the bottom portion 143 of the holding portion 140. The main body portion 160 includes a first fixing portion 161 and a second fixing portion 162, and supports the heating unit 121 by sandwiching a flange portion 122 and an extension 123 extending from the heating unit 121, between the first fixing portion 161 and the second fixing portion 162. Furthermore, the main body portion 160 is accommodated in a casing 164 having a cylindrical structure.
The heating unit 121 constitutes a blade-type heater for heating the stick-type substrate 150 inserted into the internal space 141 of the holding portion 140. The heating unit 121 protrudes into the internal space 141 through the bottom portion 143 from outside of the holding portion 140, and is thereby inserted inside the stick-type substrate 150 held in the internal space 141. The heating unit 121 may be, for example, a PTC (positive temperature coefficient) heater which generates heat by being energized.
The flange portion 122 is a projection which projects in a direction orthogonal to a direction of extension of the heating unit 121, at one end of the heating unit 121 on the opposite side to the other end protruding into the internal space 141 of the holding portion 140. The flange portion 122 is sandwiched between the first fixing portion 161 and the second fixing portion 162 by way of a horizontal support portion 163 in the direction of extension of the heating unit 121. The flange portion 122 may be formed by a material that does not generate heat as a result of energization.
The extension 123 extends in the direction of extension of the heating unit 121 from a second face S2 on the opposite side to a first face S1 of the flange portion 122 where the heating unit 121 protrudes. The extension 123 is sandwiched by the second fixing portion 162 in a direction orthogonal to the direction of extension of the extension 123. In this way, the heating unit 121 can extend in a direction perpendicular to the bottom portion 143 of the holding portion 140 as a result of the flange portion 122 and the extension 123 being fixed by the first fixing portion 161 and the second fixing portion 162. Similarly to the flange portion 122, the extension 123 may be formed by a material that does not generate heat as a result of energization.
The first fixing portion 161 supports the first face S1 of the flange portion 122 on the side on which the holding portion 140 is provided. Meanwhile, the second fixing portion 162 supports, by way of the horizontal support portion 163, the second face S2 of the flange portion 122 on the opposite side to the side on which the holding portion 140 is provided. As a result, the flange portion 122 is fixed by being sandwiched in the direction of extension of the heating unit 121 between the first fixing portion 161 and the second fixing portion 162.
Furthermore, the first fixing portion 161 is provided by a recessed structure which is open on one face on the opposite side to the side on which the holding portion 140 is provided. The second fixing portion 162 is accommodated together with the flange portion 122 inside the recessed structure of the first fixing portion 161, and has an overhang 1621 which becomes larger toward an inside face of the recessed structure of the first flange portion 161. The second fixing portion 162 is mated by causing the overhang 1621 to protrude into a cutout 1611 provided in the side face of the first fixing portion 161, whereby the second fixing portion 162 is fixed so as not to become detached from the first fixing portion 161.
The horizontal support portion 163 is provided between the second face S2 of the flange portion 122 and the second fixing portion 162. The horizontal support portion 163 controls the inclination of the heating unit 121 so that the heating unit 121 protrudes perpendicularly into the internal space 141 of the holding portion 140, by controlling the second face S2 of the flange portion 122 so as to be parallel to the bottom portion 143 of the holding portion 140. Specifically, the horizontal support portion 163 may be configured by a plurality of hemispherical portions or projecting structures, and may be provided so that peaks of the plurality of hemispheres or projecting structures are included on the same plane parallel to the bottom portion 143 of the holding portion 140. In this way, the horizontal support portion 163 can ensure perpendicularity of the heating unit 121 to the bottom portion 143 by supporting the second face S2 of the flange portion 122 on a plane parallel to the bottom portion 143 of the holding portion 140.
The casing 164 is provided by a cylindrical structure inside which the main body portion 160 is accommodated. For example, the casing 164 may be provided so as to surround the side face of the main body portion 160 with the cylindrical structure, which is formed by a metal material such as stainless steel.
In the first configuration example, a gap 171 is formed along the outer shape of the first fixing portion 161, between the first fixing portion 161 and the casing 164. The gap 171 is sealed by a sealing member 170 which is provided inside the gap 171, sandwiched between the casing 164 and the first fixing portion 161. The sealing member 170 is a ring-shaped member formed by an elastic material or metal material. For example, the sealing member 170 may be an O-ring, a gasket, or a sealing washer, etc. formed from rubber, silicone resin, various types of organic resins, or aluminum, etc.
In the inhalation device 100 according to this embodiment, a projection 144 protrudes from the first fixing portion 161 so as to cover an opening of the gap 171 at the bottom portion 143 of the holding portion 140. In this way, the inhalation device 100 is capable of reducing the amount of water flowing into the gap 171 by narrowing the opening of the gap 171 by means of the projection 144.
Furthermore, the sealing member 170 seals the gap 171 by generating stress between the casing 164 and the first fixing member 161 by means of a restoring force produced by elastic deformation. Consequently, if a force were applied to the sealing member 170 in the direction of extension of the gap 171 due to water pressure or discharge pressure of a water stream, etc., the sealing member 170 could deform, which might rupture sealing of the gap 171. In the inhalation device 100 according to this embodiment, a water stream flowing into the gap 171 can be blocked by the projection 144, so it is possible to prevent the water stream from hitting the sealing member 170 directly, and to prevent excessive water pressure from being exerted on the sealing member 170. Accordingly, the inhalation device 100 is capable of preventing water that has poured into the internal space 141 from penetrating inside the inhalation device 100 by preventing deformation of the sealing member 170. In this way, waterproofing of the inhalation device 100 can be further improved.
However, the projection 144 should not completely cover the opening of the gap 171. For example, the projection 144 may be provided so that the width of the opening of the gap 171 after being covered by the projection 144 is 0.2 mm or less. In this case also, the projection 144 is capable of increasing resistance when water flows into the gap 171, so it is possible to reduce the amount of water flowing into the gap 171. Furthermore, the projection 144 is also capable of achieving the effect of improving waterproofing of the inhalation device 100 by preventing a water stream from hitting the sealing member 170 directly.
The projection 144 may be provided so that at least the surface thereof is water-repellent. In this way, the projection 144 can further suppress penetration of water into the gap 171 by means of water repellency. For example, the projection 144 may be formed entirely by a water-repellent material, or the surface thereof may be coated with a water-repellent material. Examples of water-repellent materials that may be cited include: a silicone resin material, a fluororesin material, or a ceramic material, etc.
There is no particular limitation as to the shape of the projection 44 provided that it is capable of covering the opening of the gap 171. However, the height of an end portion of the projection 144 is preferably no less than the height of the surface of the first fixing portion 161 on which the projection 144 is provided, in order to prevent penetration of water into the gap 171 more reliably.
The shape of such a projection 144 will be described with reference to fig. 3-6. Fig. 3-6 are illustrative diagrams schematically showing examples of the cross-sectional shape of the projection 144.
The projection 144 may be configured with a shape having a rectangular cross-sectional shape, as shown in fig. 3, or may be configured with a shape having a triangular cross-sectional shape, as shown in fig. 4 and 5. The projection 144 may also be configured with a shape having a cross-sectional shape including a curve, as shown in fig. 6.
Here, a height P2 of a tip end portion of the projection 144 may be the same as (i.e., on the same surface as) a height P1 of any surface of the first fixing portion 161 on which the projection 144 is provided, as shown in fig. 3 and 4. Alternatively, the height P2 of the tip end portion of the projection 144 may be greater than the height P1 of any surface of the first fixing portion 161 on which the projection 144 is provided, as shown in fig. 5 and 6. When the height P2 of the tip end portion of the projection 144 is no less than the height P1 of any surface of the first fixing portion 161, the projection 144 is capable of preventing water from flowing into the projection 144 side along an inclination from the first fixing portion 161 to the projection 144. Accordingly, a projection 144 having the shapes above is capable of further improving waterproofing of the inhalation device 100 because it is capable of suppressing an inflow of water to the gap 171.
A variant example of the first configuration example will also be described with reference to fig. 7 and 8. Fig. 7 is a schematic view in cross section showing a variant example in which a plurality of projections 144A, 144B protrude from the first fixing portion 161. Fig. 8 is a schematic view in cross section showing a variant example in which a plurality of projections 144A, 144B protrude from the first fixing portion 161, and a counter projection 165 protrudes from the casing 164.
As shown in fig. 7, a plurality of projections 144A, 144B protrude from the first fixing portion 161 so as to cover the opening of the gap 171. For example, the plurality of projections 144A, 144B may be provided one above another in the extension direction of the gap 171. Furthermore, the areas of the plurality of projections 144A, 144B covering the opening of the gap 171 may be the same as or different from each other. In this way, the inhalation device 100 is capable of further improving waterproofing because the inflow of water to the gap 171 can be further suppressed by the plurality of projections 144A, 144B.
Furthermore, as shown in fig. 8, a counter projection 165 may further be provided on the casing 164 on a surface facing the plurality of projections 144A, 144B. The counter projection 165 mates with the opposing projections 144A, 144B and can thereby form a zigzagging flow path between the projections 144A, 144B. The counter projection 165 can therefore further increase resistance when water flows into the gap 171 from the internal space 141 of the holding portion 140. In this way, the inhalation device 100 is capable of further improving waterproofing by further suppressing inflow of water to the gap 171.
In the first configuration example, the projection 144 is provided in the main body portion 160 which includes the first fixing portion 161 and the second fixing portion 162. The projection 144 protrudes from the main body portion 160 so as to cover the opening of the gap 171 formed between the main body portion 160 and the casing 164, thereby making it possible to suppress inflow of water to the gap 171. Furthermore, the projection 144 is capable of preventing water from flowing directly into the gap 171 by blocking the opening of the gap 171. In this way, the projection 144 is capable of preventing the sealing member 170 from deforming due to water pressure, which would lead to a reduction in properties of sealing the gap 171. Accordingly, the projection 144 is capable of improving waterproofing of the inhalation device 100 because it is capable of suppressing an inflow of water from the internal space 141 to inside the inhalation device 100.

(2.2. Second configuration example)

A second configuration example of the bottom portion 143 of the holding portion 140 will be described with reference to fig. 9. Fig. 9 is a schematic view in cross section showing the second configuration example of the bottom portion 143 of the holding portion 140.
As shown in fig. 9, the main body portion 160 is provided at the bottom portion 143 of the holding portion 140. The main body portion 160 includes the first fixing portion 161 and the second fixing portion 162, and supports the heating unit 121 by sandwiching the flange portion 122 and the extension 123 extending from the heating unit 121, between the first fixing portion 161 and the second fixing portion 162. It should be noted that the heating unit 121, the flange portion 122, the extension 123, the first fixing portion 161, and the second fixing portion 162 are substantially the same as in the first configuration example and will therefore not be described again.
In the second configuration example, a gap 171 extending in the direction of extension of the heating unit 121 is formed along the outer shape of the first fixing portion 161, between the first fixing portion 161 and the heating unit 121. Furthermore, the opening of the gap 171 is covered by the projection 144 protruding from the first fixing portion 161 toward the heating unit 121. That is to say, in the second configuration example, the position where the gap 171 is formed at the bottom portion 143 of the holding portion 140 differs from that of the first configuration example.
In this case also, the projection 144 is capable of increasing resistance when water flows into the gap 171 by narrowing the width of the opening of the gap 171, and the amount of water leaking into the gap 171 can therefore be reduced, in the same way as in the first configuration example. Furthermore, the projection 144 is capable of preventing water from flowing directly into the gap 171 formed in the bottom portion 143 of the holding portion 140 by covering the gap 171. Accordingly, the projection 144 is capable of improving waterproofing of the inhalation device 100.

<3. Action and effects>

The action and effects afforded by the abovementioned projection 144 will be described in specific terms next, with reference to fig. 10 and 11. Fig. 10 is a schematic diagram showing a model for deriving the amount of water flowing through the gap 171 when no projection 144 is provided. Fig. 11 is a schematic diagram showing a model for deriving the amount of water flowing through the gap 171 when the projection 144 is provided. In fig. 10 and 11, it is assumed for simplicity that the sealing member 170 is not provided inside the gap 171.
As shown in fig. 10, if D is the width or diameter of the internal space 141 of the holding portion 140, and h₁ is the opening width of the gap 171, then the amount of water passing through a gap 171 of length L is expressed by the following equation (1), where η is the viscosity of water at a given temperature. It should be noted that P₁ in equation (1) is the pressure of the water flowing into the gap 171, and P₂ is the pressure of the water that has passed through the gap 171.
[Math. 1] $Q = \frac{{πDh}_{1}^{3}}{12 ηL} (P_{1} - P_{2})$
Meanwhile, as shown in fig. 11, if D is the width or diameter of the internal space 141 of the holding portion 140, and h₂ is the opening width of the gap 171 after being covered by the projection 144, then the amount of water passing a projection 144 of height L is expressed by the following equation (2), where η is the viscosity of water at a given temperature. It should be noted that P₁ in equation (2) is the pressure of the water flowing to the projection 144, and P₂ is the pressure of the water that has passed the projection 144.
[Math. 2] $Q = \frac{{πDh}_{2}^{3}}{12 ηL} (P_{1} - P_{2})$
As shown in equations (1) and (2) above, the amount of water passing through the gap 171 is proportional to the cube of the opening width of the gap 171 relative to the internal space 141. Accordingly, the inhalation device 100 is capable of considerably reducing the amount of water penetrating into the gap 171 by narrowing the opening width of the gap 171 by means of the projection 144.
Preferred embodiments of the present invention were described in detail above with reference to the appended drawings, but the present invention is not limited to those examples. It is obvious that a person having ordinary knowledge in the technical field to which the present invention belongs will be able to conceive of a number of variant examples or modified examples within the scope of the technical concept disclosed in the claims, and any such variant examples or modified examples are naturally understood to fall within the technical scope of the present invention.
For example, in the embodiments above, the inhalation device 100 comprises the heating unit 121 having a blade-like structure, which heats the stick-type substrate 150 from the inside, but the present invention is not limited to this example. Provided that the gap 171 is formed in the internal space 141 of the holding portion 140, there is no particular limitation as to the method for heating the stick-type substrate 150 in the inhalation device 100. For example, the inhalation device 100 may comprise a heating unit such as a film heater for heating the stick-type substrate 150 from the outside, or may comprise a heating unit such as a susceptor which is induction heated by means of a variable magnetic field.
It should be noted that the following configurations also fall within the technical scope of the present invention.

(1) An aerosol generating device comprising: a holding portion having a cylindrical structure inside which an aerosol generating substrate is inserted;
- a main body portion provided on a bottom face of the cylindrical structure,
- a gap formed in the bottom face along an outer shape of the main body portion; and
- a projection protruding from the main body portion so as to cover an opening of the gap.
(2) The aerosol generating device as disclosed in (1), wherein the projection protrudes so that the width of the opening after being covered is 0.2 mm or less.
(3) The aerosol generating device as disclosed in (1) or (2), wherein at least a surface of the projection is formed from a water-repellent material.
(4) The aerosol generating device as disclosed in (3), wherein the projection is formed from a silicone resin material, a fluororesin material, or a ceramic material.
(5) The aerosol generating device as disclosed in any one of (1) to (4), wherein the projection is provided so that the height of a tip end of the projection is no less than the height of any point from the center of the main body portion to the projection.
(6) The aerosol generating device as disclosed in any one of (1) to (5), wherein the gap is sealed by a sealing member provided inside the gap.
(7) The aerosol generating device as disclosed in any one of (1) to (6), further comprising a counter projection which is provided on a surface facing the projection and overlaps the projection.
(8) The aerosol generating device as disclosed in any one of (1) to (7), wherein the gap is provided between the main body portion and a casing for holding the main body portion from the outside.
(9) The aerosol generating device as disclosed in any one of (1) to (7), wherein the gap is provided between the main body portion and a heating unit for heating the aerosol generating substrate while protruding into the cylindrical structure from the bottom face.

[Reference Signs List]

100: Inhalation device
121: Heating unit
122: Flange portion
123: Extension
140: Holding portion
141: Internal space
142: Opening
143: Bottom portion
144: Projection
150: Stick-type substrate
151: Substrate portion
152: Mouthpiece portion
160: Main body portion
161: First fixing portion
162: Second fixing portion
163: Horizontal support portion
164: Casing
170: Sealing member
171: Gap

Claims

An aerosol generating device comprising: a holding portion having a cylindrical structure inside which an aerosol generating substrate is inserted;
a main body portion provided on a bottom face of the cylindrical structure,

a gap formed in the bottom face along an outer shape of the main body portion; and

a projection protruding from the main body portion so as to cover an opening of the gap.
The aerosol generating device as claimed in claim 1, wherein the projection protrudes so that the width of the opening after being covered is 0.2 mm or less.
The aerosol generating device as claimed in claim 1 or 2, wherein at least a surface of the projection is formed from a water-repellent material.
The aerosol generating device as claimed in claim 3, wherein the projection is formed from a silicone resin material, a fluororesin material, or a ceramic material.
The aerosol generating device as claimed in any one of claims 1 to 4, wherein the projection is provided so that the height of a tip end of the projection is no less than the height of any point from the center of the main body portion to the projection.
The aerosol generating device as claimed in any one of claims 1 to 5, wherein the gap is sealed by a sealing member provided inside the gap.
The aerosol generating device as claimed in any one of claims 1 to 6, further comprising a counter projection which is provided on a surface facing the projection and overlaps the projection.
The aerosol generating device as claimed in any one of claims 1 to 7, wherein the gap is provided between the main body portion and a casing for holding the main body portion from the outside.
The aerosol generating device as claimed in any one of claims 1 to 7, wherein the gap is provided between the main body portion and a heating unit for heating the aerosol generating substrate while protruding into the cylindrical structure from the bottom face.