CN113645863A

CN113645863A - Electronic cigarette cartridge with compressible wick

Info

Publication number: CN113645863A
Application number: CN202080025255.7A
Authority: CN
Inventors: H.希玛
Original assignee: JT International SA
Current assignee: JT International SA
Priority date: 2019-03-27
Filing date: 2020-03-25
Publication date: 2021-11-12
Also published as: JP2022524698A; EP3945904A1; CA3144691A1; EP3945905A1; WO2020193657A1; US20220117301A1; TW202038752A; JP2022524909A; US20220104547A1; WO2020193655A1; EP3945906A1; KR20210143781A; TW202038753A; KR20210143782A; JP2022524570A; CA3134644A1; KR20210143780A; TW202042684A; US20220079234A1; CA3134632A1

Abstract

An e-vaping cartridge (611) with a liquid reservoir (606) and a fluid transfer element (604) is provided. The fluid transfer element (604) includes a compressible wick (609) and a flexible contact surface. The fluid transfer element (604) is configured to receive liquid from the liquid reservoir (606), and the flexible contact surface is configured to release liquid held in the compressible wick (609) from the e-cartridge (611) when the fluid transfer element (604) is compressed.

Description

Electronic cigarette cartridge with compressible wick

Technical Field

The present invention relates to electronic cigarettes, and more particularly to fluid storage cartridges for electronic cigarettes.

Background

In electronic smoking products, the aerosol-forming substance, or vaporizable substance, is stored in a canister in liquid form. The canister typically has an outlet connected to a wicking element or fluid transfer element which supplies the aerosol-or vapour-forming substance to the atomiser. In addition to the fluid transfer element, the nebulizer comprises a heating arrangement for vaporizing the liquid aerosol-forming substance.

Electronic cigarettes rely on power stored locally in a battery and therefore need to provide extended battery life for such devices. It is therefore an object of the present invention to address such challenges.

US 2014/069424 a1 describes a device for atomising or vaporising a liquid for inhalation. WO2016/198417a1 describes a cartridge for use in an electrically operated aerosol generating system.

Disclosure of Invention

The claims address the foregoing objects and other problems of the invention.

According to a first aspect of the present disclosure there is provided a vaporiser for an e-cigarette comprising a fluid transfer element and a heater, wherein the fluid transfer element is compressible and is configured to transfer a portion of liquid from a liquid reservoir to the heater, and wherein a contact surface of the fluid transfer element and the heater are configured to move relative to each other such that, when the contact surface of the fluid transfer element is compressed, liquid may be released from the fluid transfer element and may be adsorbed on the heater.

In this way, a controlled portion of the liquid may be transferred to the heater for heating, and heat is not spread to and within the liquid reservoir, thereby improving energy efficiency, as only the liquid to be vaporized is heated. Preferably, the portion of liquid corresponds to a single vaporising suck of the user.

Preferably, the vaporizer further comprises a compression element arranged to move from a first position spaced from the contact surface of the fluid transfer element to a second position closer to the contact surface of the fluid transfer element.

Preferably, the heater is arranged on the compression element such that when the compression element is in the second position, the heater moves relative to the contact surface and is pressed against the contact surface of the fluid transfer element, whereby a portion of the liquid is released from the fluid transfer element and adsorbed on the heater, and wherein the heater is arranged to vaporise the adsorbed portion of the liquid when the compression element has moved from the second position to the first position.

In this way, a controlled portion of the liquid is transferred directly to the heater by movement of the heater. By moving the heater away from the fluid transfer element, unnecessary heating of the liquid held in the fluid transfer element and transfer of heat to the liquid reservoir is inhibited, heating only the predetermined dose, thereby improving the energy efficiency of the e-cigarette.

Alternatively, the heater is statically disposed inside the e-cigarette and is positioned proximate to a contact surface of the fluid transfer element, and the compression element is configured to move the contact surface relative to the heater when the compression element moves between the first position and the second position, and the compression element is configured to compress the contact surface such that liquid is released from the contact surface when the compression element is in the second position, and the heater is disposed to vaporize the adsorbed portion of the liquid when the compression element is in the first position.

Preferably, when the compression element is in the second position, a fluid bridge is created between the contact surface and the heater, whereby a portion of the liquid releasable from the fluid transfer element may be adsorbed on the heater in the second position.

Alternatively, the compression element is configured to compress the contact surface and create a distance between the contact surface and the heater when in the second position, and the compression element is released from the contact surface when in the first position such that the contact surface contacts the heater in the first position and transfers the liquid.

In this way, the heater is maintained at a distance from the fluid transfer element, thereby inhibiting the heater from transferring heat to the fluid transfer element and heating the liquid held therein. The transfer of heat to the liquid reservoir is also inhibited. This prevents liquid in excess of the predetermined dose from being unnecessarily heated, thereby improving the energy efficiency of the e-cigarette.

Alternatively, in the first position, the heater is proximate to but spaced from the fluid transfer element and the contact surface moves relative to the heater when the compression element compresses the contact surface by moving from the first position to the second position. When the compression element compresses the contact surface, a portion of the liquid releasable from the fluid transfer element may be adsorbed on the heater, and the heater is arranged to vaporize the adsorbed portion of the liquid when the compression element has moved from the second position to the first position.

Preferably, the fluid transfer element comprises a compressible wick.

In this way, the wick may wick and store liquid from the liquid reservoir and may be compressed to release the liquid, which is adsorbed on the heater.

Preferably, the fluid transfer element further comprises a mesh disposed on a heater-facing surface of the wick, wherein the mesh and wick are compressed when the compression element is pressed against the contact surface of the fluid transfer element, such that in use, a portion of the liquid in the wick passes through the mesh.

In this way, the mesh helps to inhibit liquid from escaping from the wick, so that by forming a liquid seal when the fluid transfer element is not deformed by the compression element, liquid does not leak through the e-cigarette.

Preferably, the mesh is hydrophobic.

In this way, the inhibition of liquid escaping from the wick through the mesh and adsorption on the heater is enhanced. Preferably, the hydrophobic coating on the mesh provides hydrophobic properties.

Preferably, the fluid transfer element further comprises a liquid buffer arranged to transport liquid from the liquid reservoir to the wick by capillary action.

In this way, controlled flow of liquid to the wick is provided by buffering the liquid flow.

Preferably, the liquid buffer comprises a plurality of plates arranged to extend from the wick towards the liquid reservoir, channels being arranged between the plates such that, in use, liquid is drawn from the liquid reservoir to the wick by capillary action.

In this way, the liquid is buffered by capillary action so that the liquid reaches the wick in a controlled manner.

Preferably, the fluid transfer element has a piercing member extending therefrom for piercing a cartridge containing the liquid reservoir and transporting liquid from the cartridge through the piercing member towards the wick.

In this way, the fluid transfer element has a dual function in that it serves both to pierce the cartridge and to transfer the liquid therein to the heater. This is advantageous because in a single action the cartridge is opened and the liquid therein engages with the fluid transfer element for transfer to the heater. In addition, the user does not have to manually open the cartridge, thereby avoiding potential spillage. Preferably, the piercing member is a tube having a pointed end. Preferably, the piercing member has a sufficiently narrow aperture to enable liquid to be transported from the cartridge by capillary action. Preferably, the cartridge is a disposable consumable and the component is disposed in a reusable portion of the e-cigarette. Preferably, the reusable part of the e-cigarette is a battery part.

Preferably, the heater comprises a ceramic structure.

Preferably, the heater comprises a ceramic structure and a printed or embedded heating track connected to the ceramic structure, wherein the ceramic structure comprises a non-porous ceramic having a porous ceramic disposed on a first surface thereof, and wherein the heating track is disposed on a second surface of the non-porous ceramic.

In this way, the liquid adsorption characteristics of the heater are enhanced. Preferably, the heater wicks the liquid into the pores of the porous ceramic. The heater may be selected from the group comprising: spiral coils, mesh, or printed or embedded surface heaters. The heater may comprise a ceramic disc. Preferably, the non-porous ceramic is quartz. Preferably, the second surface of the non-porous ceramic is the opposite surface to the first surface of the non-porous ceramic. The heating track may be a resistive heating element.

According to a second aspect of the present disclosure, there is provided a cartridge for an electronic cigarette, the cartridge comprising a vaporiser according to the first aspect and further comprising a liquid reservoir.

In this way, the component may be disposed in a reusable portion of the e-cigarette, such as a battery portion, and the disposable cartridge may be removed and replaced when spent.

According to a third aspect of the present disclosure, there is provided a method for operating the vaporizer of the first aspect, the method comprising: compressing the contact surface of the fluid transfer element such that liquid is released from the fluid transfer element; establishing a fluidic bridge between the released liquid and the heater such that a portion of the released liquid is adsorbed onto the heater; and heating the adsorbed liquid by the heater to generate a vapor when the fluid bridge is broken.

In this way, the controlled liquid portion is heated and heat is not spread to and within the liquid reservoir, thereby improving energy efficiency, as only the liquid to be vaporized is heated.

According to a fourth aspect of the present disclosure, there is provided an e-cartridge comprising a liquid reservoir and a fluid transfer element, the fluid transfer element comprising a compressible wick and a flexible contact surface, wherein the fluid transfer element is configured to receive liquid from the liquid reservoir, and wherein the flexible contact surface is configured to release liquid held in the compressible wick from the e-cartridge when the fluid transfer element is compressed.

In this way, the release of liquid from the liquid reservoir when the fluid transfer element is not compressed is inhibited.

Preferably, the liquid reservoir is fluidly connected to the compressible wick through an opening between the liquid reservoir and the fluid transfer element.

In this way, the liquid reservoir and the compressible wick may be contained in separate portions of the e-cigarette cartridge. The liquid reservoir may be a consumable product that is simple and economical to produce, while the fluid transfer element may be a reusable part.

Alternatively, the compressible wick is located inside the liquid reservoir.

In this way, the compressible wick and the liquid reservoir may be contained in the same portion of the cartridge, such that liquid in the liquid reservoir may be readily ingested by the wick.

Alternatively, the fluid transfer element further comprises a plug housing a compressible wick, the plug receivable in the liquid reservoir and having a first end arranged to face liquid in the liquid reservoir, and wherein a buffer is arranged on the first end to wick liquid from the liquid reservoir to the wick.

Preferably, the liquid buffer comprises a plurality of plates arranged to extend from the compressible wick into the liquid reservoir, with channels arranged between the plates such that, in use, liquid is drawn from the liquid reservoir to the compressible wick by capillary action.

In this way, liquid is buffered by the channels between the plates via capillary action, so that the liquid reaches the wick in a controlled manner.

Alternatively, the fluid transfer element is located external to the liquid reservoir, and the liquid reservoir may be engaged by the fluid transfer element such that, in operation, the fluid transfer element transfers a portion of the liquid from the liquid reservoir into the heater in the e-cigarette.

In this way, the liquid reservoir can be replaced and the fluid transfer element can be reused.

Preferably, the fluid transfer element further comprises a mesh arranged on a surface of the compressible wick such that the mesh forms the flexible contact surface, and wherein the mesh is arranged to allow liquid to pass through the mesh upon application of compression to the compressible wick.

In this manner, the mesh helps to inhibit the escape of liquid from the wick by forming a liquid seal when the fluid transfer element is not deformed or compressed.

Preferably, the mesh is hydrophobic.

In this way, the inhibition of liquid escaping from the wick through the mesh is enhanced. Preferably, the hydrophobic coating on the mesh provides hydrophobic properties.

According to a fifth aspect of the present disclosure there is provided an electronic cigarette for use with the electronic cigarette cartridge of the fourth aspect, the electronic cigarette comprising a compression element and a heater, wherein the compression element is arranged to move relative to the fluid transfer element from a first position spaced from the fluid transfer element to a second position pressed against a flexible contact surface of the fluid transfer element to compress the compressible wick such that liquid is releasable from the wick and adsorbable on the heater.

Preferably, the heater is disposed on the compression element such that when the compression element is in the second position, the heater is pressed against the flexible contact surface of the fluid transfer element and a portion of the liquid releasable from the compressible wick is adsorbable on the heater, and the heater is disposed for vaporising the adsorbed liquid portion when the compression element is released from the contact surface.

In this way, a controlled liquid portion is transferred directly to the heater by the movement of the compression element. By moving the heater away from the fluid transfer element, unnecessary heating of the liquid held in the fluid transfer element and transfer of heat to the liquid reservoir is inhibited, heating only the predetermined dose, thereby improving the energy efficiency of the e-cigarette.

Alternatively, the heater is adjacent to but separate from the fluid transfer element and arranged such that when the compression element is in the second position the compression element is pressed against the flexible contact surface of the fluid transfer element and thereby a portion of the liquid is released from the compressible wick and adsorbed on the heater, and the heater is arranged to vaporise the adsorbed portion of the liquid when the compression element has moved from the second position to the first position.

According to a sixth aspect of the present disclosure, there is provided a method of operating the electronic cigarette of the fifth aspect, the method comprising: moving the compression element against the flexible contact surface of the fluid transfer element to cause liquid to be released from the fluid transfer element; establishing a fluidic bridge between the released liquid and the heater such that a portion of the released liquid is adsorbed onto the heater; and heating the adsorbed liquid by the heater to generate a vapor when the fluid bridge is broken.

According to a seventh aspect of the present disclosure, there is provided a fluid transfer component for an electronic cigarette, the fluid transfer component being configured for establishing a fluid connection between a liquid reservoir of the electronic cigarette and a heater, wherein the fluid transfer component comprises: a liquid intake member configured to be coupled to the housing of the liquid reservoir; a chamber configured to receive liquid from the liquid reservoir through the liquid intake member; and a fluid transfer element comprising a compressible wick configured to transport liquid from the chamber to the vicinity of the heater by capillary action and a flexible contact surface configured to deform in an axial direction of the fluid transfer component, wherein the flexible contact surface is configured to release liquid from the compressible wick for transfer to the heater when the fluid transfer element is compressed.

In this way, a fluid transfer member may be used to connect a liquid reservoir of an e-cigarette, such as a cartridge, to a heater in a simple and efficient manner.

Preferably, the fluid transfer component is releasably connected to the liquid reservoir by the liquid intake member.

In this way, an expired liquid reservoir may be released from the fluid transfer component and replaced in a simple and efficient manner. The fluid transfer component may be connected to a universal liquid reservoir to create a liquid reservoir having fluid transfer capabilities.

Preferably, the liquid intake member is an elongate tube extending from the chamber and provided with a tip configured to be received in the liquid reservoir such that liquid can enter the elongate tube at the tip for transfer to the chamber.

In this manner, the liquid intake member transfers liquid from the liquid reservoir to the compressible wick. Preferably, the elongate tube has a sufficiently narrow aperture to enable liquid to be delivered from the liquid reservoir by capillary action.

Preferably, the liquid intake member is arranged to form a friction fit with an opening in the liquid reservoir.

In this way, the liquid intake member forms a firm and snug connection with the opening in the liquid reservoir through the sealing connection, such that leakage of liquid from the liquid reservoir is inhibited.

Preferably, the tip comprises a tip of the elongate tube arranged to pierce a housing of the liquid reservoir.

In this way, the fluid transfer member may be used to pierce a liquid reservoir or cartridge and transfer liquid from the liquid reservoir to the fluid transfer element. This is advantageous because in a single action, both the liquid reservoir can be opened and the liquid therein can be brought into engagement with the fluid transfer element for transfer from the liquid reservoir.

Preferably, the mesh is hydrophobic.

Preferably, the fluid transfer component is removably attached to the e-cigarette.

In this way, the fluid transfer component may be a consumable component that may be replaced at the end of its working life. This avoids the need to replace the entire e-cigarette when, for example, the compressible wick needs to be replaced.

In another aspect, the fluid transfer component is fluidly coupled to the liquid reservoir of the cartridge by the liquid intake member.

According to an eighth aspect of the present disclosure there is provided an electronic cigarette for use with the fluid transfer component of the seventh aspect, the electronic cigarette comprising a wicking compressor and a heater, wherein the wicking compressor is arranged to move relative to the fluid transfer element from a first position spaced from the fluid transfer element to a second position pressed against a flexible contact surface of the fluid transfer element to compress the compressible wick such that liquid is releasable from the wick and adsorbable on the heater.

Preferably, the heater is arranged on the wicking compressor such that the heater is pressed against the flexible contact surface of the fluid transfer element when the wicking compressor moves from the first position to the second position and a portion of the liquid releasable from the compressible wicking member can adsorb on the heater; and the heater is arranged to vaporize the adsorbed liquid portion when the wicking compressor has moved from the second position to the first position.

In this way, the controlled liquid portion is transferred directly to the heater by the movement of the wicking compressor. By moving the heater away from the fluid transfer element, unnecessary heating of the liquid held in the fluid transfer element and transfer of heat to the liquid reservoir is inhibited, heating only the predetermined dose, thereby improving the energy efficiency of the e-cigarette.

Alternatively, the heater is proximate to but separate from the fluid transfer element and the wicking compressor and arranged such that the wicking compressor is pressed against the flexible contact surface of the fluid transfer element when moving from the first position to the second position, a portion of the liquid releasable from the compressible wick being adsorbable on the heater; and the heater is arranged to vaporize the adsorbed liquid portion when the wicking compressor has moved from the second position to the first position.

According to a ninth aspect of the present disclosure, there is provided a method for operating the electronic cigarette of the eighth aspect, the method comprising: moving the wicking compressor to press against the flexible contact surface of the fluid transfer element to cause liquid to be released from the fluid transfer element; establishing a fluidic bridge between the released liquid and the heater such that a portion of the released liquid is adsorbed onto the heater; and heating the adsorbed liquid by the heater to generate a vapor when the fluid bridge is broken.

Drawings

Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which:

figure 1A shows a cross-sectional view of an e-cigarette cartridge in an e-cigarette;

1B-1D show cross-sectional views of a compressible wick in an e-cigarette cartridge when compressed by a heater;

FIGS. 2A to 2E are sectional views showing the operation of causing the heater to compress the wick;

FIG. 3 shows a diagram of a drop on a hydrophobic mesh;

fig. 4A to 4D show diagrams representing liquid adsorbed on a heater when vaporized;

figures 5A to 5C show cross-sectional views of a compressible wick in an e-cigarette cartridge when compressed by a wick compressor;

FIGS. 6A and 6B show cross-sectional views of a cartridge with a compressible wick;

figures 7A and 7B show exploded views of a cartridge with a compressible wick; and

figure 8A shows a cross-sectional view of the vaporizer engaged with a cartridge.

Figure 8B shows a cross-sectional view of an alternative arrangement in which the vaporiser engages with the cartridge.

Detailed Description

Figure 1A shows an electronic cigarette 100 having a vaporizer arrangement, while figures 1B-1D show the vaporizer arrangement 102 in more detail for use in an electronic cigarette. The vaporizer arrangement 102 comprises a compressible fluid transfer element 104 and a heater 105 that is movable relative to a flexible contact surface 110 of the fluid transfer element 104. In an example, the heater 105 has a ceramic structure with printed or embedded heating tracks. The ceramic structure may be a non-porous ceramic having a porous ceramic layer on its surface. The fluid transfer element 104 includes a compressible wick 109 that can be saturated with a vaporizable liquid. In the example of figure 1A, the compressible fluid transfer element 104 is arranged in a releasable cartridge 111 configured to be connected to a cartridge mount 190 in a housing 129 of the body of the e-cigarette, and the heater 105 is arranged as part of the body of the e-cigarette. Compressible wick 109 is arranged to absorb liquid 121 from liquid reservoir 106 in cartridge 111, and then liquid 121 spreads through wick 109 such that wick 109 becomes saturated. The wick may be composed of a compressible porous or fibrous material, such as cotton or silica. Alternatively, the liquid reservoir may be a refillable liquid reservoir integral with an electronic cigarette having a fluid transfer element.

The heater 105 is connected by a compression element 103 to a motor or solenoid 137 in the housing 127 of the body of the e-cigarette. The cartridge may be housed in the same or different housing portion as the heater, compression element and motor in the e-cigarette. The heater 105 moves into contact with the contact surface 110 of the fluid transfer element 104 and deforms the contact surface 110 of the fluid transfer element 104, thereby compressing the wick 109 and releasing liquid held in the wick 109 from the contact surface 110. The liquid held in wick 109 is adsorbed onto the surface of heater 105. A porous ceramic layer at the surface of the heater may assist in the transfer of liquid to the heater by capillary action. The heater 105 is then retracted from the contact surface 110, and the heater is configured to heat the adsorbed liquid to generate a vapor when the heater 105 is separated from the contact surface 110. This process is described in more detail in fig. 1B to 1D, and fig. 2A to 2E. The e-cigarette 100 has a mouthpiece 131 on which a user of the e-cigarette 100 may draw to inhale the generated vapor. When a user sucks on the suction nozzle 131, the steam is sucked to the suction nozzle 131 through the steam pipe 135. The vapor enters the vapor tube 135 at a first end of the vapor tube near the heater and exits the vapor tube 135 at a second end of the vapor tube connected to the suction nozzle 131.

Fig. 1B-1D illustrate the release and vaporization of liquid from the cartridge in more detail.

In fig. 1B, the heater 105 is separated from the compressible surface of the fluid transfer element 104. The heater 105 is connected to a driver, such as a motor or solenoid (as described with reference to fig. 1A, but not shown in fig. 1B-1D), through the compression element 103. The heater 105 and driver are powered by a power source, such as a battery, within the body of the e-cigarette.

The actuator is arranged to move the heater 105 relative to the surface of the fluid transfer element 104 from a position spaced from the surface of the fluid transfer element 104 (as shown in fig. 1B) to: in this position, the heater 105 contacts and deforms the contact surface 110 of the fluid transfer element 104, thereby compressing the fluid transfer element 104 (as shown in fig. 1C).

The compression applied to the fluid transfer element 104 causes the liquid held in the fluid transfer element 104 to be released from the fluid transfer element 104 at the contact surface 110 (similar to squeezing a saturated sponge). The released liquid 113 is adsorbed onto the surface of the heater 105.

The driver is further arranged to move the heater 105 relative to the surface of the fluid transfer element 104 by moving the heater 105 from a position in contact with and compressing the fluid transfer element 104 (as shown in fig. 1C) back to a position in which the heater 105 is separated from the fluid transfer element 104 (as shown in fig. 1D). Thus, after the liquid 115 is adsorbed onto the surface of the heater 105, the driver retracts the heater 105 from the fluid transfer element 104 with the adsorbed liquid 115 on the surface of the heater 105. Retracting the heater 105 releases the compression applied to the fluid transfer element 104, so that the wick 109 draws liquid from the liquid reservoir to replace the liquid adsorbed onto the heater 105. That is, the driver drives the heater 105 into the surface of the fluid transfer element 104 and retracts it from the surface of the fluid transfer element 104, wherein liquid from the fluid transfer element 104 is adsorbed onto the heater 105. When retracted from the fluid transfer element 104, the heater 105 applies thermal energy to the adsorbed liquid 115, thereby heating and vaporizing the adsorbed liquid 115 to produce a vapor. The vapor may then be inhaled by a user of the e-cigarette through the mouthpiece.

The surface of the wick 109 facing the heater 105 may form a flexible contact surface 110 of the fluid transfer element 104. That is, the wick 109 itself may be the fluid transfer element 104. In some embodiments, the fluid transfer element 104 may further comprise a hydrophobic mesh 107 disposed on a surface of the wick 109 between the wick 109 and the heater 105. When included, the hydrophobic mesh 107 may be configured as the contact surface 110 of the heater 105. That is, the fluid transfer element 104 may be both the wick 109 and the mesh 107. As such, when the heater 105 contacts the contact surface 110 and compresses the fluid transfer element 104, the heater deforms both the hydrophobic mesh 107 and the wick 109. Due to this compression, liquid held in the wick 109 passes through the mesh 107. The hydrophobic nature of the mesh 107 causes liquid that has passed through the mesh 107 to be repelled and form droplets on the surface of the mesh 107 (as shown in fig. 3), rather than being drawn back through the mesh 107 into the wick 109. This facilitates the adsorption of the liquid 115 onto the heater 105. Additionally, the hydrophobic mesh 107 prevents the liquid 121 from escaping from the cartridge 111 when no compression is applied. Air may pass through mesh 107, thereby providing breathability. In an embodiment, the mesh 107 may have a metallic structure and be provided with a hydrophobic coating. Alternatively, the mesh 107 itself may be made of a hydrophobic material, such as a nonwoven material. The hydrophobic material or coating may be Polytetrafluoroethylene (PTFE) or teflon. The hydrophobic mesh may have material properties that make it elastically flexible to allow deformation; the hydrophobic mesh may also have structural properties that provide flexibility, such as being convex dome-shaped or raised to allow deformation. To further increase the ability of the liquid 115 to be adsorbed onto the heater 105, the heater 105 may be hydrophilic. The hydrophilic heater 105 characteristics also help assist in wetting the heater 105 surface so that the liquid 115 is evenly distributed over the heater 105. This improves the heating efficiency.

In some examples, the cartridge 111 has a barrier 123 disposed between the wick 109 and the liquid 121 in the liquid reservoir 106. An orifice 125 is provided in barrier 123 between wick 109 and liquid 121 in liquid reservoir 106 so that liquid 121 can flow from liquid reservoir 106 to wick 109 in a controlled manner. The barrier 123 also holds the wick 109 in place against the mesh 107 at the end of the cartridge 111 to interact with the heater 105.

Fig. 2A to 2E are diagrams showing the operation steps of the vaporizer 102 described with reference to fig. 1.

The heater 105 is connected to a compression element 103 which is operatively connected to a driver. The driver may be a motor or solenoid (as described with reference to fig. 1A, but not shown in fig. 2A-2E) arranged to urge the heater 105 towards and away from the fluid transfer element 104. Fluid transfer element 104 includes a compressible wick 109 having a contact surface 110 facing the liquid in liquid reservoir 111, and a contact surface opposite the first surface. The contact surface 110 may be a portion of the same material as the fluid transfer element. Alternatively, as previously described, the hydrophobic mesh 107 may be configured to contact the surface 110.

Initially, as shown in fig. 2A, the heater 105 is separated from the fluid transfer element 104. The compression element 103 moves the heater 105 against the contact surface 110 and compresses the fluid transfer element 104, as shown in fig. 2B. This causes a portion of the liquid 113 held in the wick 109 to be released from the wick 109 and pass through the mesh 107 where it contacts the heater 105. The liquid is adsorbed onto the surface of the heater 105. The surface of the heater 105 may comprise a porous ceramic, and the capillary action provided by such a material may assist in the transfer of the released liquid 113 to the heater 105.

The compression element 103 then retracts the heater 105 from the fluid transfer element. The adsorbed liquid 115 portion is also withdrawn from the mesh 107 onto the heater 105, as shown in FIG. 2C. This results in the arrangement of fig. 2D, where the heater 105 and adsorbed liquid 115 are separated from the fluid transfer element. Fig. 4A shows a heater 105 in which a liquid layer 115 is absorbed onto a surface and wets it. Retracting heater 105 removes the compression applied to the fluid transfer element, which causes the fluid transfer element to return to its uncompressed state and in doing so, wick 109 draws more liquid from liquid reservoir 111.

When the heater 105 is separated from the fluid transfer element 104, power is supplied to the heater 105 from a power source, such as a battery in an electronic cigarette. The supplied power heats the heater 105 such that the heater 105 transfers thermal energy to the adsorbed liquid 115. This transfer of thermal energy to the adsorbed liquid 115 raises the temperature of the adsorbed liquid 115 such that the adsorbed liquid 115 is vaporized and produces a vapor 117, as shown in fig. 2E. This vapor 117 may then be inhaled by the user through the mouthpiece of the e-cigarette 100.

In this way, it is only necessary to heat the portion of liquid absorbed on the heater 105 to its vaporization point. This requires less energy than heating a larger volume of liquid, for example, held in a liquid tank, to its vaporization point. As such, these power savings in heating enable longer battery life of the e-cigarette 100. Furthermore, the separation of the heater 105 and the liquid reservoir 106 prevents heat from spreading in the liquid reservoir 106, which would further waste energy.

Fig. 4A, 4B, 4C, and 4D illustrate the progress of vaporization of the heater 105 over a period of time. As the vaporization time passes, the amount of adsorbed liquid 115 remaining on the heater 105 decreases as it is converted to vapor 117: starting from fig. 4A (before vaporization begins) to fig. 4B (where some of the liquid has vaporized), to fig. 4C (where most of the liquid has vaporized), and finally to fig. 4D (where all of the liquid has vaporized).

When the adsorbed liquid 115 has vaporized, the operation returns to the state as described with reference to fig. 2A.

In some examples, the position of the heater 105 oscillates back and forth from contacting the contact surface 110 and compressing the fluid transfer element to separating from the fluid transfer element. In this way, vaporizer operation is repeatedly cycled through compression-adsorption-retraction-vaporization cycles, as described with reference to fig. 2A-2E.

Fig. 5 shows a diagram of an alternative vaporizer 502 arrangement as described with reference to fig. 1 and 2. This embodiment is also based on the following arrangement: the contact surfaces of the heater and the fluid transfer element are movable relative to each other and, thus, heat is transferred only to the adsorbed liquid when the heater is separated from the contact surfaces.

In the embodiment shown in fig. 5, only the contact surface (or fluid transfer surface) 510 of cartridge 511 is movable, while heater 505 is stationary. The heater 505 is held in a fixed position from the cartridge 511 and the separate compression element 503 deforms the contact surface 510 of the fluid transfer element 504, thereby compressing the fluid transfer element 504.

In this arrangement, the vaporizer 502 includes a compressible fluid transfer element 504; a heater 505 held at a fixed displacement from the cartridge 511; and a compression element 503, such as a piston or an elongated rod, configured to compress fluid transfer element 504 by deforming flexible contact surface 510 of fluid transfer element 504 facing heater 505. The plunger is configured to move into and out of contact surface 510 of fluid transfer element 504, and this deformation of contact surface 510 of fluid transfer element 504 causes contact surface 510 of fluid transfer element 504 to move relative to the fixed position of heater 505.

The fluid transfer element 504 is housed within a cartridge 511 and includes a compressible wick 509 that can be saturated with a vaporizable liquid. In the example of figure 5, the compressible fluid transfer element 504 is arranged in a cartridge 511 adapted to be seated inside the cartridge body 190 of the e-cigarette, and the heater 505 and compression element 503 are arranged as part of the body of the e-cigarette. The compressible wick 509 is arranged to absorb liquid 521 from the liquid reservoir 506 in the cartridge 511, the liquid 521 then spreading through the wick 509 such that the wick 509 becomes saturated. The surface of wick 509 facing heater 505 may form flexible contact surface 510 of fluid transfer element 504. That is, the wick 509 itself may be the fluid transfer element 504. In some embodiments, fluid transfer element 504 may further comprise a hydrophobic mesh 507 (corresponding to that described with reference to fig. 1) disposed on a surface of wick 509 between wick 509 and heater 505. When included, the hydrophobic mesh 507 may be configured to contact the surface 510. That is, the fluid transfer element may be both the wick 109 and the mesh 107. Similar to the previous embodiments, the fluid transfer element 504 may optionally further comprise a hydrophobic mesh 507 to cover the surface of the wick 509 opposite the surface facing the liquid 521 in the liquid reservoir 506. The hydrophobic nature of mesh 507 causes liquid that has passed through mesh 507 to be repelled and form droplets on the surface of mesh 507 (as shown in fig. 3), rather than being drawn back through mesh 507 into wick 509.

In the example of fig. 5, compression element 503 is an elongated rod or piston disposed through ring heater 505. The elongate rod is connected to a driver (not shown), such as a solenoid or motor, which drives the elongate rod from a position spaced from the fluid transfer element 504 (as shown in fig. 5A) to: in this position, the elongated rod contacts and deforms contact surface 510 of fluid transfer element 504, thereby compressing fluid transfer element 504 (as shown in fig. 5B). That is, the driver drives the compression element 503 into the contact surface 510 of the fluid transfer element 504 and retracts it from the contact surface 510 of the fluid transfer element 504.

The heater 505 and driver are powered by a power source, such as a battery, within the body of the e-cigarette. In other examples, compression member 503 may have any other shape suitable for moving into and out of contact with fluid transfer member 504 while abutting against heater 505.

When the compression element 503 pushes against the contact surface 510 of the fluid transfer element 504, the compression applied to the wick 509 of the fluid transfer element 504 due to the deformation applied to the contact surface 510 of the fluid transfer element 504 causes the liquid 513 held in the wick 509 to be released, as shown in fig. 5B. In embodiments including hydrophobic mesh 507 as contact surface 510, liquid held in wick 509 is released through hydrophobic mesh 507. Heater 505 is positioned such that the surface of heater 505 is in close proximity to contact surface 510 of fluid transfer element 504, such that droplets 515 are attracted to heater 505 by the fluid bridges, thereby wetting the surface of heater 505, as shown in FIG. 5C. Optionally, heater 505 may have hydrophilic properties to facilitate the transfer of liquid from the contact surface of mesh 507 to the surface of heater 505. The surface of heater 505 may comprise a porous ceramic, and the capillary action provided by such material may assist in the transfer of released liquid 513 to heater 505.

Next, the compression element 503 is retracted from the contact surface 510 of the fluid transfer element 504. Removal of compression returns the fluid transfer element 504 to its uncompressed state, and in so doing, the wick 509 draws more liquid from the liquid reservoir 506.

Heater 505 is powered by a power source, such as a battery in an e-cigarette. When liquid 515 adsorbs onto the surface of heater 505, heater 505 applies thermal energy to the adsorbed liquid 515, and this thermal energy transfer to the adsorbed liquid 515 raises the temperature of the adsorbed liquid 515, causing the adsorbed liquid 515 to vaporize and produce a vapor. The vapor may then be inhaled by a user of the e-cigarette through the mouthpiece.

Similar to that described with reference to fig. 2A-2E, compression element 503 may oscillate back and forth from contacting and deforming contact surface 510 of fluid transfer element 504 to separate from fluid transfer element 504. In this manner, vaporizer 502 operation is repeatedly cycled through a compression-adsorption-retraction-vaporization cycle.

In some examples, similar to those described with reference to fig. 1, a barrier 523 is provided in the cartridge 511 between the wick 509 and the liquid 521 in the liquid reservoir 506. An orifice 525 is provided in barrier 523 between wick 509 and liquid 521 in liquid reservoir 506, so that liquid 521 can flow from liquid reservoir 506 to wick 509 in a controlled manner. The barrier also holds the wick 509 in place against the mesh 507 at the end of the cartridge 511 to interact with the heater 505.

The example described with reference to fig. 5 provides the same power saving advantages as described with reference to fig. 1 and 2, since only a small portion of the liquid adsorbed on the heater needs to be heated when generating the vapor, rather than a larger volume of liquid in the liquid tank.

In an alternative arrangement similar to and closely related to that described with reference to fig. 5, the contact surface of the fluid transfer element contacts the heater when the compression element is in the first position. When the compression element is moved to the second position, the contact surface is deformed and the wick is compressed such that the contact surface moves away from the heater, thereby creating a distance between the contact surface and the heater. This compression causes liquid held in the wick to be released through the contact surface, such that the released liquid forms a fluid bridge and the liquid is adsorbed onto the surface of the heater. The heater then heats and vaporizes the adsorbed liquid. The compression element retracts from the contact surface and returns to the first position. The deformation of the contact surface and the compression of the wick is released so that the contact surface again contacts the heater. Applying compression and release compression to the wick as the compression element moves between the first and second positions provides a pumping action that can further draw liquid from the liquid reservoir into the wick. All of the features described with reference to figure 5 may be used with this arrangement where appropriate.

Fig. 6A and 6B illustrate another embodiment of a cartridge 611 suitable for use with a heater as described with reference to fig. 1, 2 and 5; fig. 7A and 7B show exploded views of such cartridges 611. The cartridge 611 includes a wicking component of the vaporizer. The cartridge 611 is configured to be inserted into an electronic cigarette such that the fluid transfer element 604 of the cartridge is arranged to cause the heater of the electronic cigarette to form a vaporizer, such as described with reference to figures 1, 2 and 5.

The cartridge 611 has a housing 641 defining a liquid reservoir 606, the housing 641 being substantially cylindrical in shape with one open end. Although the examples are described as cylindrical, any other suitable shape may be used.

A plug 627 is positioned in the open end of the housing 641 with the outer diameter of the plug 627 being substantially equal to the inner diameter of the housing 641 for a snug fit. The plug 627 has a cavity 649 defined by a side wall 645 adjacent to the wall of the housing 641 and a bottom wall 647 perpendicular to the side wall, which is disposed at the end of the plug facing the interior of the housing 641 of the cartridge 611. The end of the plug 627 opposite the bottom wall 647 of the plug 627 has an outwardly extending flange portion 643 which has an outer diameter greater than the inner diameter of the housing 641. This provides an abutment to the open end of the housing 641 thereby forming a stop point for the plug 627 as it slides into the housing 641 and prevents the plug 627 from sliding further into the housing 641 beyond the stop point. Wick 609 is contained within cavity 649 and is sized to substantially fill cavity 649. The bottom wall 647 of the plug 627 has a series of openings so that liquid held within the liquid reservoir 606 of the cartridge 611 can enter the cavity 649 of the plug 627 where it is absorbed by the wick 609.

Optionally, the openings in the bottom wall 647 of the plug 627 are defined by a series of plates 629 arranged side by side and defining a flow channel 631 in the longitudinal direction of the cartridge. Thus, the plates 629 define a series of channels 631 extending from the fluid reservoir 606 into the cavity 649 of the plug 627. These plates 629 extend outwardly from the plug 627 and into the liquid reservoir 606. These channels 631 are sized such that they provide capillary action to draw liquid from the liquid reservoir 606 into the cavity 649 acting as a liquid buffer to be absorbed by the wicking element 609. In this example, the combination of channels 631 between plate-like extensions 629 and wick 609 forms fluid transfer element 604. As described subsequently, the fluid transfer element 604 may further include a hydrophobic mesh 607 (corresponding to that described with reference to fig. 1). In use, when the fluid transfer element 604 is compressed and subsequently released, liquid is drawn into the channel 631. This provides a pumping action to deliver liquid from the liquid reservoir 606 to the space defined between the plates 629 forming the channels 631. Thus, the space between them provides a liquid reservoir or buffer held in proximity to the fluid transfer element. This ensures that liquid is supplied to the fluid transfer element 604 and reduces the risk of the fluid transfer element 604 being starved of liquid.

The wick 609 is compressed by deforming the contact surface 610 facing outwardly towards the cartridge, such that when compressed, a portion of the liquid held in the wick 609 is released from the contact surface 610. That is, the fluid transfer element 604 has a flexible contact surface.

The surface of the wick 609 facing outward from the cartridge 611 may form a flexible contact surface 610 of the fluid transfer element 604. In some embodiments, the fluid transfer element 604 may further comprise a hydrophobic mesh 607 disposed on the surface of the wick 609 facing outward from the cartridge 611. When hydrophobic mesh 609 is included, hydrophobic mesh 507 may be configured to contact surface 510. The hydrophobic nature of the mesh 607 provides two primary functions. First, the hydrophobic nature prevents liquid stored in wick 609 from escaping through mesh 607 when wick 609 and mesh 607 are not compressed. Second, when liquid passes through the mesh 607 after it is compressed, the hydrophobic properties cause the liquid to form droplets on the surface of the mesh 607, rather than passing back through the mesh 607. In this way, the droplets may be attracted to the heater.

In some examples, the cartridge 611 is a disposable consumable that will be replaced after the liquid stored in the cartridge is depleted. The expired cartridge 611 is removed from the e-cigarette and a fresh cartridge 611 filled with liquid is inserted into the e-cigarette.

The use of the cartridge 611 described with reference to fig. 6 and 7 provides a power saving advantage similar to that described with reference to fig. 1 and 2, in that it provides for extracting a smaller portion of the liquid to be heated, rather than heating a larger volume of liquid in the liquid tank to produce vapor.

In other examples, the cartridge 611 is reusable and refillable. For example, the plug 627 may be removed from the housing 641 such that additional liquid may be added. The plug may then be reassembled and the cartridge may be reconnected to the e-cigarette.

Figures 8A and 8B illustrate cross-sectional views of other embodiments of a vaporization system 800 for an e-cigarette. Similar to the previously described embodiments, the system in fig. 8a and 8b is configured to provide dosing capability and avoid the heater 805 transferring heat to the liquid reservoir or cartridge 811. As shown, the vaporization system 800 includes a liquid reservoir or cartridge 811 in a seat 890 of a housing 829 of the e-cigarette body, a fluid transfer component 804, and a heater 805. The liquid reservoir or cartridge 811, the fluid transfer component 804, and the heater are configured as separable parts. Instead of being housed in cartridge 811, fluid transfer component 804 may be a separate component and include chamber 855, fluid transfer element 857, piercing member 833, and fluid transfer surface (or heater contact surface) 810. These separate parts of the vaporization system allow a simple construction of the liquid reservoir, which makes it easy to produce.

The shape of the fluid transfer member 804 corresponds to the contact area of the heater 805. The fluid transfer component 804 may be disc-shaped with a piercing member 833 extending from one face disposed in a direction toward the cartridge 811 or cartridge holder 890 of the electronic cigarette. As shown in fig. 8A, the fluid transfer component 804 may be removably attached to the housing 839 of the e-cigarette body. As shown in fig. 8B, the fluid transfer component 804 may be attached to only the liquid reservoir or cartridge 811. Optionally, the two portions of the

housings

829, 839 may be separate to allow a user of the e-cigarette to access, and remove or replace, the fluid transfer member 804.

The piercing member 833 is preferably in the shape of an elongated tube having a tip 835 and is arranged to pierce the cartridge or liquid reservoir 811 and contact the liquid within the liquid reservoir of the cartridge 811. A passage 837 extends through the elongated spike to draw liquid to the disc-shaped portion of the fluid transfer member. The piercing member 833 connects the e-cigarette with the cartridge 811 and provides a fluid connection between the body 839 of the e-cigarette and the liquid reservoir of the cartridge 811. The piercing member 833 forms a sealed connection with the cartridge 811 by a friction fit to prevent leakage. Optionally, the cartridge 811 has a depression 851 in the surface arranged for engaging the piercing element such that the piercing element is guided to the correct area on the cartridge 811. The cartridge 811 is preferably made of a plastic material, with suitable rigidity to store the vaporisable liquid, whilst being suitably thin to be pierced by the piercing member 833. In an alternative example, the piercing member 833 may be replaced with a tube arranged to be received in the cartridge 811. In such instances, the cartridge may have a tear-off seal; when the seal is torn off, the opening in the cartridge that receives the tube is exposed. The tube may form a sealed connection with the cartridge by a friction fit in the opening to prevent leakage.

The disc-shaped portion of the fluid transfer member 804 includes a fluid transfer element 857 and a chamber 855. A first side of the fluid transfer element 857 faces a chamber 855 located between the fluid transfer element 857 and the elongated spike and in fluid connection with a channel 837 extending through the elongated spike, and a second side opposite the first side is the contact surface 810.

The fluid transfer member 804 is disposed inside the e-cigarette 800 with the heater 805. The heater 805 may be arranged to deform the fluid transfer surface 810 by being pushed into the fluid transfer surface 810 by a motor or solenoid to which it is attached by a compression element 803, as described with reference to fig. 1 and 2. Alternatively, the heater 805 may be held at a fixed distance from the fluid transfer surface 810 and deformed by a separate compression element 853, such as a piston or an elongated rod (as described with reference to fig. 5). In both cases, the deformation applied to fluid transfer surface 810 releases liquid through fluid transfer surface 810, which is adsorbed onto heater 805 and vaporized. The surface of heater 805 may comprise a porous ceramic, and the capillary action provided by such material may assist in the transfer of the released liquid to heater 805.

In some embodiments, fluid transfer element 857 is wick 809 (liquid received from chamber 855 wicking through channel 837) and fluid transfer surface 810 (or contact surface 810) is a surface of wick 809 arranged to face the heater. Optionally, the fluid transfer element may further comprise a hydrophobic mesh 807 (corresponding to the hydrophobic mesh described with reference to fig. 1) to cover the surface of the wick 809 that is arranged to face the heater. When included, the hydrophobic mesh 807 forms the fluid transfer surface 810 (or contact surface 810) of the fluid transfer element 857.

Liquid stored in wick 809 is released from fluid transfer surface 810 and adsorbed onto the heater by deforming fluid transfer surface 810 as wick 809 is compressed. When the hydrophobic mesh 807 is included, the released liquid passes through the hydrophobic mesh 807 to form droplets on the surface of the hydrophobic mesh 807, which are adsorbed onto the heater.

In use, the cartridge 811 is inserted into an electronic cigarette and pierced by the piercing member 833. The liquid in the cartridge 811 is drawn through the piercing member 833 to the wick 809 by, for example, capillary action and/or pumping due to compression and decompression of the wick 809. The heater 805 or the compression element 853 deforms the contact surface 810 (i.e., the surface of the wick 809 or hydrophobic mesh 807 (if included)) and compresses the wick 809, thereby releasing the liquid stored in the wick 809. If a hydrophobic mesh 807 is included, the liquid is released from the wick 809 through the hydrophobic mesh 807 and the liquid forms droplets on the surface of the hydrophobic mesh 807. The liquid is adsorbed onto the surface of the heater 805 where it is heated to produce a vapor. The generated vapor may then be inhaled by the user through the mouthpiece of the e-cigarette. When the liquid content of the cartridge 811 is empty, the cartridge 811 may be removed from the piercing member 833 and replaced with a new cartridge 811 storing a fresh supply of vaporizable liquid or a refill cartridge.

The example described with reference to fig. 8 provides the same advantages as described with reference to fig. 1, 2 and 5, since only the portion of the liquid absorbed on the heater needs to be heated to its vaporization point. This requires less energy than heating a larger volume of liquid, for example, held in a liquid tank, to its vaporization point. In this way, these power savings in heating enable longer battery life of the e-cigarette. Furthermore, the separation of the heater and the liquid reservoir prevents heat from being distributed throughout the liquid reservoir, which would further waste energy.

Those skilled in the art will appreciate that the features in the various examples described herein can be readily substituted for one another, where appropriate, throughout all embodiments.

Claims

1. An e-vaping cartridge (611) comprising a liquid reservoir (606) and a fluid transfer element (604), the fluid transfer element comprising a compressible wick (609) and a flexible contact surface (610);

wherein the fluid transfer element is configured to receive liquid from the liquid reservoir, and wherein the flexible contact surface is configured to release liquid retained in the compressible wick from the e-cigarette cartridge when the fluid transfer element is compressed.

2. The e-cartridge of claim 1, wherein the liquid reservoir is fluidly connected to the compressible wick through an opening between the liquid reservoir and the fluid transfer element.

3. The e-cigarette cartridge of claim 1, wherein the compressible wick is located inside the liquid reservoir.

4. The e-cigarette cartridge of claim 1, wherein the fluid transfer element further comprises a plug (627) containing the compressible wick, the plug receivable in the liquid reservoir and having a first end disposed to face liquid in the liquid reservoir, and wherein a buffer is disposed on the first end to wick liquid from the liquid reservoir to the wick.

5. The e-cartridge of claim 4, wherein the liquid buffer comprises a plurality of plates (629) arranged to extend from the compressible wick into the liquid reservoir, channels (631) being arranged between the plates such that, in use, liquid is drawn from the liquid reservoir to the compressible wick by capillary action.

6. The e-cigarette cartridge of claim 1, wherein the fluid transfer element is located outside of the liquid reservoir and the liquid reservoir is engageable by the fluid transfer element such that, in operation, the fluid transfer element transfers a portion of liquid from the liquid reservoir into a heater in an e-cigarette.

7. The e-cartridge according to any of claims 1 to 6, wherein the fluid transfer element further comprises a mesh (607) arranged on a surface of the compressible wick such that the mesh forms the flexible contact surface, and wherein the mesh is arranged to allow liquid to pass through the mesh upon application of compression to the compressible wick.

8. The e-cigarette cartridge of claim 7, wherein the mesh is hydrophobic.

9. An electronic cigarette for use with an electronic cigarette cartridge as claimed in any preceding claim, the electronic cigarette comprising: a compression element (103; 503) and a heater (105; 505);

wherein the compression element is arranged to move relative to the fluid transfer element from a first position spaced from the fluid transfer element to a second position pressed against a flexible contact surface of the fluid transfer element to compress the compressible wick such that liquid (115; 515) is releasable from the wick and adsorbable on the heater.

10. The electronic cigarette of claim 9, wherein the heater (105) is disposed on the compression element (103) such that the heater is pressed against the flexible contact surface of the fluid transfer element when the compression element is in the second position and a portion of the liquid releasable from the compressible wick is adsorbable on the heater; and is

Wherein the heater is arranged for vaporizing the adsorbed liquid portion (115) when the compression element is released from the contact surface.

11. The electronic cigarette of claim 9, wherein the heater (505) is proximate to but separate from the fluid transfer element and is arranged such that when the compression element (503) is in the second position the compression element is pressed against the flexible contact surface of the fluid transfer element and thereby a portion of the liquid is released from the compressible wick and adsorbed on the heater; and is

Wherein the heater is arranged to vaporise the adsorbed liquid portion (515) when the compression element has moved from the second position to the first position.

12. A method for operating an electronic cigarette according to any of claims 9 to 11, the method comprising:

moving the compression element against the flexible contact surface of the fluid transfer element to cause liquid to be released from the fluid transfer element;

establishing a fluidic bridge between the released liquid and the heater such that a portion of the released liquid is adsorbed onto the heater; and

the adsorbed liquid is heated by the heater to generate a vapor when the fluid bridge is broken.