Field of Invention

The present invention relates to electronic cigarettes, and more specifically fluid transfer components for electronic cigarettes.

Background

In electronic cigarette products, an aerosol-forming, or vaporisable, substance is stored in a tank in liquid form. The tank typically has an outlet connected to a wicking or fluid transfer element which supplies the aerosol or vapour forming substance to an atomiser. In addition to the fluid transfer element, the atomiser also includes a heating arrangement that vaporises the liquid aerosol or vapour forming substance.

Electronic cigarettes rely on the power stored locally in batteries, and there is a need to provide increased battery life for such devices. An object of the present invention is, therefore, to address such a challenge.

Summary

The foregoing object of the invention, as well as other problems, is addressed by the claims.

According to a first aspect of the disclosure, there is provided a vaporizer for an electronic cigarette, the vaporizer comprising a fluid transfer element and a heater, wherein the fluid transfer element is compressible and configured to transfer a portion of liquid from a liquid store to the heater, and wherein a contact surface of the fluid transfer element and the heater are configured to move relative each other such that when the contact surface of the fluid transfer element is compressed, liquid is releasable from the fluid transfer element and adsorbable on the heater. In this way, a controlled portion of liquid can be transferred to the heater to be heated, and heat does not spread to and within a liquid store, thereby improving the energy efficiency as only liquid to be vaporised is heated. Preferably the portion of liquid corresponds to one vaporization puff by a user.

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

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

Alternatively, the heater is stationary arranged inside the electronic cigarette and located proximal to the contact surface of the fluid transfer element, and the compressing element is configured to move the contact surface relative to the heater as the compressing element moves between the first position and the second position, and the compressing element in the second position is configured to compress the contact surface such that liquid is released from the contact surface, and the heater is arranged to vaporise the adsorbed portion of liquid when the compressing element is in the first position. Preferably, a fluidic bridge is created between the contact surface and the heater when the compressing element is in the second position, whereby a portion of liquid releasable from the fluid transfer element is adsorbable on the heater in the second position.

Alternatively, the compressing element in the second position is configured to compress the contact surface and create a distance between the contact surface and the heater, and the compressing element in the first position is released from the contact surface such that the contact surface contacts the heater in the first position and transfers 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. Heat transfer to the liquid store is also inhibited. This prevents unnecessary heating of liquid beyond the predetermined dose thereby improving the energy efficiency of the electronic cigarette.

Alternatively, in the first position the heater is proximal to but separated from the fluid transfer element and the contact surface moves relative to the heater when the compressing element compresses the contact surface by moving from the first position to the second position. When the compressing element compresses the contact surface a portion of liquid releasable from the fluid transfer element is adsorbable on the heater, and the heater is arranged to vaporise an adsorbed portion of liquid when the compressing 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 can wick and store liquid from the liquid store, and can be compressed to release liquid to be adsorbed on the heater.

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

In this way, the mesh contributes to inhibiting liquid escaping from the wick, so that liquid does not leak through an electronic cigarette, by forming a liquid seal when the fluid transfer element is not being deformed by the compressing element.

Preferably, the mesh is hydrophobic.

In this way, the inhibiting of liquid escaping the wick through the mesh is enhanced, as well as the adsorption onto the heater. Preferably the hydrophobic properties are provided by a hydrophobic coating on the mesh.

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

In this way, a 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 toward a liquid store, with channels arranged between the plates such that in use liquid is drawn from a liquid store to the wick by capillary action.

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

Preferably, the fluid transfer element has a piercing member extending therefrom so as to pierce a cartridge comprising the liquid store and transport liquid from the cartridge toward the wick through the piercing member.

In this way, the fluid transfer element has dual functionality in that it is used to both pierce the cartridge and transfer liquid therein to the heater. This is beneficial as in a single action the cartridge is both opened and the liquid therein engaged with the fluid transfer element for transfer to the heater. Additionally, the user does not have to manually open the cartridge, thereby avoiding potential spillage. Preferably the piercing member is a tube with a pointed end. Preferably the piercing member has a sufficiently narrow bore for liquid to be transported from the cartridge by capillary action. Preferably the cartridge is a disposable consumable whilst the component is arranged in a reusable portion of an electronic cigarette. Preferably the reusable portion of the electronic cigarette is the battery portion.

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 with a porous ceramic arranged on a first surface thereof, and wherein the heating track is arranged on a second surface of the non-porous ceramic

In this way, the liquid adsorption properties of the heater are enhanced. Preferably the heater adsorbs the liquid by capillary action into the pores of the porous ceramic. The heater may be selected from a group comprising a spiral shaped coil, a mesh, or a printed or embedded surface heater. The heater may comprise a ceramic disc. Preferably the non-porous ceramic is quartz. Preferably the second surface of the non-porous ceramic is a surface opposite the first surface of the non-porous ceramic. The heating track may be a resistive heating element.

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

In this way, the component can be arranged in a reusable portion, such as a battery portion, of the electronic cigarette whilst the disposable cartridge can be removed and replaced when spent. According to a third aspect of the disclosure there is provided a method of 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 vapour when the fluidic bridge is broken.

In this way, a controlled portion of liquid is heated, and heat does not spread to and within the liquid store, thereby improving the energy efficiency as only liquid to be vaporised is heated.

According to a fourth aspect of the disclosure there is provided an electronic cigarette cartridge comprising a liquid store 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 store and wherein the flexible contact surface is configured to release liquid held in the compressible wick from the electronic cigarette cartridge when the fluid transfer element is compressed.

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

Preferably, the liquid store is fluidically connected to the compressible wick by an opening between the liquid store and the fluid transfer element.

In this way, the liquid store and the compressible wick can be contained in separate portions of the electronic cigarette cartridge. The liquid stores can be simple and economical to produce consumable, while the fluid transfer element can be a re-usable part.

Alternatively, the compressible wick is located inside the liquid store. In this way, the compressible wick and the liquid store can be contained in the same portion of the cartridge such that liquid in the liquid store can be readily taken up by the wick.

Alternatively, the fluid transfer element further comprises a plug in which the compressible wick is housed, the plug being receivable in the liquid store and having a first end arranged to face liquid in the liquid store and wherein a buffer is arranged on the first end to transport liquid from the liquid store to the wick by capillary action.

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

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

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

Alternatively, the fluid transfer element is located outside the liquid store, and the liquid store is engageable by the fluid transfer element such that, in operation, the fluid transfer element transfers a portion of liquid from the liquid store to a heater in an electronic cigarette.

In this way, the liquid store can be replaced and the fluid transfer element can be re-used.

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 there through when a compression is applied to the compressible wick. In this way, the mesh contributes to inhibiting liquid escaping from the wick by forming a liquid seal when the fluid transfer element is not being deformed or compressed.

Preferably, the mesh is hydrophobic.

In this way, the inhibiting of liquid escaping the wick through the mesh is enhanced. Preferably the hydrophobic properties are provided by a hydrophobic coating on the mesh.

According to a fifth aspect of the disclosure there is provided an electronic cigarette for use with the electronic cigarette cartridge of the fourth aspect, the electronic cigarette comprising a compressing element and a heater, wherein the compressing element is arranged to move relative to the fluid transfer element from a first position separated from the fluid transfer element to a second position pressing against the 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.

In this way, a controlled portion of liquid can be transferred to the heater to be heated, and heat does not spread to and within a liquid store, thereby improving the energy efficiency as only liquid to be vaporised is heated. Preferably the portion of liquid corresponds to one vaporization puff by a user.

Preferably, the heater is arranged on the compressing element such that the heater is pressed against the flexible contact surface of the fluid transfer element when the compressing element is in the second position and a portion of liquid releasable from the compressible wick is adsorbable on the heater, and the heater is arranged to vaporise an adsorbed portion of liquid when the compressing element is released from the contact surface.

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

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

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. Heat transfer to the liquid store is also inhibited. This prevents unnecessary heating of liquid beyond the predetermined dose thereby improving the energy efficiency of the electronic cigarette.

According to a sixth aspect of the disclosure there is provided a method of operating the electronic cigarette of the fifth aspect, the method comprising moving the compressing element to press against the flexible 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 vapour when the fluidic bridge is broken.

In this way a controlled portion of liquid is heated, and heat does not spread to and within the liquid store, thereby improving the energy efficiency as only liquid to be vaporised is heated.

According to a seventh aspect of the disclosure there is provided a fluid transfer component for an electronic cigarette, the fluid transfer component being configured to establish a fluidic connection between a liquid store and a heater in an electronic cigarette, wherein the fluid transfer component comprises: a liquid uptake member configured to connect with a housing of the liquid store, a chamber configured to receive liquid from the liquid store by the liquid uptake member, and a fluid transfer element comprising a compressible wick configured to transport liquid from the chamber to the proximity of the heater by capillary action and a flexible contact surface configured to deform in the 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, the fluid transfer component can be used to connect a liquid store, such as a cartridge, to the heater of an electronic cigarette in a simple and efficient manner.

Preferably, the fluid transfer component is releasably connectable to the liquid store by the liquid uptake member.

In this way, an expired liquid store can be released from the fluid transfer component and replaced in a simple and efficient manner. The fluid transfer component can be connected to a generic liquid store to create a liquid store with fluid transfer capabilities.

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

In this way, the liquid uptake member transfers liquid from the liquid store to the compressible wick. Preferably the elongated tube has a sufficiently narrow bore for liquid to be transported from the liquid store by capillary action.

Preferably, the liquid uptake member is arranged to form a friction fit with an opening in the liquid store. In this way, the liquid uptake member forms a secure and snug connection with the opening in the liquid store with a sealed connection such that liquid leakage from the liquid store is inhibited.

Preferably, the tip comprises a pointed end of the elongated tube arranged to pierce a housing of the liquid store.

In this way, the fluid transfer component can be used to pierce a liquid store or cartridge and transfer liquid from the liquid store to the fluid transfer element. This is beneficial as in a single action the liquid store can be both opened and the liquid therein engaged with the fluid transfer element for transfer from the liquid store.

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 there through when a compression is applied to the compressible wick.

In this way, the mesh contributes to inhibiting liquid escaping from the wick by forming a liquid seal when the fluid transfer element is not being deformed or compressed.

Preferably, the mesh is hydrophobic.

In this way, the inhibiting of liquid escaping the wick through the mesh is enhanced. Preferably the hydrophobic properties are provided by a hydrophobic coating on the mesh.

Preferably, the fluid transfer component is removably attachable to the electronic cigarette.

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

In another aspect, the fluid transfer component is fluidically coupled to a liquid store of a cartridge by the liquid uptake member.

According to an eighth aspect of the disclosure there is provided an electronic cigarette for use with the fluid transfer component of the seventh aspect, there electronic cigarette comprising a wick compressor and a heater, wherein the wick compressor is arranged to move relative to the fluid transfer element from a first position separated from the fluid transfer element to a second position pressing against the 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.

In this way, a controlled portion of liquid can be transferred to the heater to be heated, and heat does not spread to and within a liquid store, thereby improving the energy efficiency as only liquid to be vaporised is heated. Preferably the portion of liquid corresponds to one vaporization puff by a user.

Preferably, the heater is arranged on the wick compressor such that the heater is pressed against the flexible contact surface of the fluid transfer element when the wick compressor moves from the first position to the second position and a portion of liquid releasable from the compressible wick is adsorbable on the heater, and the heater is arranged to vaporise an adsorbed portion of liquid when the wick compressor has moved from the second position to the first position.

In this way, the controlled portion of liquid is transferred directly onto the heater by movement of the wick compressor. By moving the heater away from the fluid transfer element the unnecessary heating of liquid held in the fluid transfer element, and heat transfer to the liquid store, is inhibited; only a predetermined dose is heated, thereby improving the energy efficiency of the electronic cigarette. Alternatively, the heater is proximal to but separated from the fluid transfer element and the wick compressor, and arranged such that when the wick 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 liquid releasable from the compressible wick is adsorbable on the heater, and the heater is arranged to vaporise an adsorbed portion of liquid when the wick compressor has moved from the second position to the first position.

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. Heat transfer to the liquid store is also inhibited. This prevents unnecessary heating of liquid beyond the predetermined dose thereby improving the energy efficiency of the electronic cigarette.

According to a ninth aspect of the disclosure there is provided a method of operating the electronic cigarette of the eighth aspect, the method comprising: moving the wick compressor to press against the flexible 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 vapour when the fluidic bridge is broken.

In this way a controlled portion of liquid is heated, and heat does not spread to and within the liquid store, thereby improving the energy efficiency as only liquid to be vaporised is heated.

Brief Description of the Drawings

Embodiments of the invention are now described, by way of example, with reference to the drawings, in which: Figure 1A shows a cross-sectional diagram of an electronic cigarette cartridge in an electronic cigarette;

Figures 1 B to 1 D show cross-sectional diagrams of a compressible wick in an electronic cigarette cartridge being compressed by a heater;

Figures 2A to 2E show cross-sectional diagrams of the operation of a heater compressing a wick;

Figure 3 shows a diagram of liquid drops on a hydrophobic mesh;

Figures 4A to 4D show diagrams representing liquid adsorbed on a heater being vaporised;

Figures 5A to 5C show cross-sectional diagrams of a compressible wick being in an electronic cigarette cartridge being compressed by a wick compressor;

Figures 6A and 6B show cross-sectional diagrams 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 diagram of a vaporiser engaging a cartridge.

Figure 8B shows a cross-sectional diagram of an alternate arrangement of a vaporiser engaging a cartridge.

Detailed Description

Figure 1A shows an electronic cigarette 100 with a vaporiser arrangement, and Figures 1 B to 1 D show the vaporiser arrangement 102 for use in the electronic cigarette in more detail. The vaporiser arrangement 102 includes a compressible fluid transfer element 104 and a heater 105 which is moveable relative to a flexible contact surface 1 10 of the fluid transfer element 104. In an example, the heater 105 has a ceramic structure with a printed or embedded heating track. The ceramic structure may be a non-porous ceramic with a porous ceramic layer on its surface. The fluid transfer element 104 comprises a compressible wick 109 capable of being saturated with a vaporisable liquid. In the example of Figure 1A, the compressible fluid transfer element 104 is arranged in a releasable cartridge 1 1 1 configured to be connected to a cartridge seating 190 in a housing 129 of the main body of the electronic cigarette, and the heater 105 is arranged as part of the main body of the electronic cigarette. The compressible wick 109 is arranged to absorb liquid 121 from a liquid store 106 in the cartridge 1 11 ; the liquid 121 then spreads through the wick 109 such that the wick 109 becomes saturated. The wick may consist of a compressible porous or fibrous material, such as cotton or silica. Alternatively the liquid store can be a refillable liquid store integral to the electronic cigarette with the fluid transfer element.

The heater 105 is connected by a compressing element 103 to a motor or solenoid 137 in a housing 127 the main body of the electronic cigarette. The cartridge may be housed in either the same or a different housing part as the heater, compressing element and motor in the electronic cigarette. The heater 105 is moved into contact with the contact surface 110 of the fluid transfer element 104 and deforms the contact surface 1 10 of the fluid transfer element 104, thereby compressing the wick 109 and releasing liquid held in the wick 109 from the contact surface 1 10. Liquid held in the wick 109 is adsorbed onto the surface of the heater 105. A porous ceramic layer at the surface of the heater can aid 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 vapour as the heater 105 is separated from the contact surface 1 10. This process is described in more detail with respect to Figures 1 B to 1 D, and 2A to 2E. The electronic cigarette 100 has a mouthpiece 131 upon which a user of the electronic cigarette 100 can draw to inhale the generated vapour. When the user draws on the mouthpiece 131 , the vapour is drawn to the mouthpiece 131 by a vapour tube 135. The vapour enters the vapour tube 135 at a first end of the vapour tube proximal to the heater and exits the vapour tube 135 at a second end of the vapour tube connected to the mouthpiece 131.

Figures 1 B to 1 D show the release and vaporisation of liquid from the cartridge in more detail.

In Figure 1 B the heater 105 is separated from the compressible surface of the fluid transfer element 104. The heater 105 is connected by an compressing element 103 to a driver such as a motor or solenoid (as described with reference to Figure 1A, but not shown in Figures 1 B to 1 D). The heater 105 and the driver are powered by a power supply, such as a battery, within the main body of the electronic cigarette.

The driver is arranged to move the heater 105 relative to the surface of the fluid transfer element 104, from a position separated from the surface of the fluid transfer element 104 (as shown in Figure 1 B) to a position wherein the heater 105 is in contact with and is deforming the contact surface 1 10 of the fluid transfer element 104 thereby compressing the fluid transfer element 104 (as shown in Figure 1 C).

The compression applied to the fluid transfer element 104 causes liquid held in the fluid transfer element 104 to be released from the fluid transfer element 104 (akin to squeezing a saturated sponge) at the contact surface 1 10. This released liquid 1 13 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 the position wherein it is in contact with and compressing the fluid transfer element 104 (as shown in Figure 1 C), back to the position wherein the heater 105 is separated from the fluid transfer element 104 (as shown in Figure 1 D). As such, following the adsorption of liquid 1 15 onto the heater 105 surface, the driver retracts the heater 105 from the fluid transfer element 104 with the adsorbed liquid 115 on the surface of the heater 105. The retraction of the heater 105 releases the compression applied to the fluid transfer element 104, consequently the wick 109 draws in liquid from the liquid store 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 with liquid from the fluid transfer element 104 adsorbed on 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 vaporising the adsorbed liquid 115 to generate a vapour. This vapour can then be inhaled by the user of the electronic cigarette through a mouthpiece.

The surface of the wick 109 facing the heater 105 can form the flexible contact surface 1 10 of the fluid transfer element 104. That is, the wick 109 itself can be the fluid transfer element 104. In some embodiments, the fluid transfer element 104 may further comprise a hydrophobic mesh 107 arranged on a surface of the wick 109 between the wick 109 and the heater 105. When the hydrophobic mesh is included, the hydrophobic mesh 107 may be configured as the contact surface 110 for the heater 105. That is, the fluid transfer element 104 can be both the wick 109 and the mesh 107. As such, when the heater 105 contacts the contact surface 1 10 and compresses the fluid transfer element 104, it deforms both the hydrophobic mesh 107 and the wick 109. As a result of the compression, the liquid held in the wick 109 passes through the mesh 107. The hydrophobic nature of the mesh 107 causes the liquid that has passed through the mesh 107 to be repelled and form droplets on the surface of the mesh 107 (as illustrated in Figure 3) rather than soaking back through the mesh 107 into the wick 109. This benefits the adsorption of liquid 115 onto the heater 105. Additionally, the hydrophobic mesh 107 prevents liquid 121 from escaping the cartridge 1 11 when a compression is not applied. Air can pass through the mesh 107 providing breathability. In an embodiment, the mesh 107 can have a metallic structure and be provided with a hydrophobic coating. Alternatively, the mesh 107 can itself be made from a hydrophobic material, such as a nonwoven material. The hydrophobic material or coating may be polytetrafluoroethylene (PTFE) or Teflon. The hydrophobic mesh can have material properties that make resiliently flexible so as to allow for a deformation; the hydrophobic mesh can also have structural properties providing flexibility such as being convexly dome-shaped or bulging to allow for deformation. To further increase the proficiency for liquid 1 15 to be adsorbed onto the heater 105, the heater 105 can be hydrophilic. Hydrophilic heater 105 properties are also beneficial in aiding the wetting of the heater 105 surface such that an even distribution of liquid 1 15 across the heater 105 is achieved. This enhances the efficiency of the heating.

In some examples, the cartridge 11 1 has a barrier 123 provided between the wick 109 and the liquid 121 in the liquid store 106. An aperture 125 is provided in the barrier 123 between the wick 109 and the liquid 121 in the liquid store 106 so that liquid 121 can flow from the liquid store 106 to the wick 109 in a controlled manner. The barrier 123 also holds the wick 109 in position at the end of the cartridge 1 11 , against the mesh 107, for interaction with the heater 105.

Figures 2A to 2E show diagrams of operational steps of the vaporiser 102 described with reference to Figure 1.

The heater 105 is connected to a compressing element 103 operationally connected to a driver. The driver can be a motor or solenoid (as described with reference to Figure 1A, but not shown in Figures 2A to 2E) which is arranged to drive the heater 105 toward and away from the fluid transfer element 104. The fluid transfer element 104 comprises a compressible wick 109 with a contact surface 1 10 facing liquid in the liquid store 1 11 , and a contact surface opposite the first surface. The contact surface 110 can be part of the same material as the fluid transfer element. Alternatively, as previously described, a hydrophobic mesh 107 may be configured as the contact surface 110.

Initially, as shown in Figure 2A, the heater 105 is separated from the fluid transfer element 104. The compressing element 103 moves the heater 105 against the contact surface 1 10 and compresses and the fluid transfer element 104, as shown in Figure 2B. This causes a portion of the liquid held in the wick 109 to be released 1 13 from the wick 109 and to pass through the mesh 107 where it comes into contact with the heater 105. The liquid adsorbs onto the surface of the heater 105. The surface of the heater 105 can include a porous ceramic; capillary action provided by this material can aid the transfer of the released liquid 113 to the heater 105.

The compressing element 103 then retracts the heater 105 from the fluid transfer element. The portion of adsorbed liquid 1 15 also retracts from the mesh 107 on the heater 105, as shown in Figure 2C. This leads to the arrangement of Figure 2D, wherein the heater 105 and adsorbed liquid 1 15 are separated from the fluid transfer element. Figure 4A shows a heater 105 with a layer of liquid 1 15 adsorbed onto and wetting the surface. The retraction of the heater 105 results in a removal of the compression applied to the fluid transfer element, this causes the fluid transfer element to return to its non-compressed state and in doing so the wick 109 draws in more liquid from the liquid store 1 11.

When the heater 105 is separated from the fluid transfer element 104, power is supplied to the heater 105 from a power supply such as a battery in the electronic cigarette. The supplied power heats the heater 105 such that the heater 105 transfers thermal energy to the adsorbed liquid 1 15. This transfer of thermal energy to the adsorbed liquid 1 15 elevates the temperature of the adsorbed liquid 1 15 such that the adsorbed liquid 115 is vaporised and a vapour 1 17 is generated, as shown in Figure 2E. This vapour 117 can then be inhaled by a user through the mouthpiece of the electronic cigarette 100.

In this way, only the portion of liquid absorbed on the heater 105 need be heated to its vaporisation point. This requires less energy than heating a larger volume of liquid, for example held in a liquid tank, to its vaporisation point. As such, these power savings in heating lead to a longer battery life in the electronic cigarette 100. Furthermore, the separation of the heater 105 and the liquid store 106 prevents heat spreading through the liquid store 106 which would further waste energy.

Figures 4A, 4B, 4C and 4D show the progression of the vaporisation from the heater 105 over a period of time. As the vaporisation time elapses, the amount of adsorbed liquid 1 15 remaining on the heater 105 decreases as it is converted to vapour 1 17, starting from Figure 4A, before the vaporisation begins, to Figure 4B where some of the liquid has been vaporised, to Figure 4C where most of the liquid has been vaporised, and finally Figure 4D where all of the liquid has been vaporised.

When the adsorbed liquid 115 has been vaporised, the operation returns to the state as described with reference to Figure 2A.

In some examples, the heater 105 position oscillates back and forth from being in contact with the contact surface 110 and compressing the fluid transfer element to being separated from the fluid transfer element. In this way, the vaporiser operation repeatedly cycles through the compression-adsorption- retraction-vaporisation cycle as described with reference to Figures 2A to 2E.

Figure 5 shows a diagram of an alternative vaporiser 502 arrangement to that described with reference to Figures 1 and 2. This embodiment is also based upon an arrangement in which the heater and the contact surface of the fluid transfer element are movable in relation to each other and whereby heat is only transferred to the adsorbed liquid when the heater is separated from the contact surface.

In the embodiment illustrated in Figure 5, only the contact surface (or fluid transfer surface) 510 of the cartridge 51 1 is movable, while the heater 505 is stationary. The heater 505 is held at a fixed position from the cartridge 51 1 and a separate compressing element 503 deforms the contact surface 510 of the fluid transfer element 504 thereby compressing the fluid transfer element 504.

In this arrangement, the vaporiser 502 includes a compressible fluid transfer element 504, a heater 505 which held at a fixed displacement from the cartridge 51 1 , and a compressing element 503 such as a piston or elongate rod configured to compress the fluid transfer element 504 by deforming the flexible contact surface 510 of the fluid transfer element 504 facing the heater 505. The piston is configured to move into and away from the contact surface 510 of the fluid transfer element 504; this deforming of the contact surface 510 of the fluid transfer element 504 results in the contact surface 510 of the fluid transfer element 504 moving relative to the fixed position of the heater 505.

The fluid transfer element 504 is housed within a cartridge 51 1 and comprises a compressible wick 509 capable of being saturated with a vaporisable liquid. In the example of Figure 5, the compressible fluid transfer element 504 is arranged in a cartridge 511 suitable for being seated inside the cartridge seating 190 of an electronic cigarette, and the heater 505 and the compressing element 503 are arranged as part of the main body of the electronic cigarette. The compressible wick 509 is arranged to absorb liquid 521 from a liquid store 506 in the cartridge 51 1 ; the liquid 521 then spreads through the wick 509 such that the wick 509 becomes saturated. The surface of the wick 509 facing the heater 505 can form the flexible contact surface 510 of the fluid transfer element 504. That is, the wick 509 itself can be the fluid transfer element 504. In some embodiments, the fluid transfer element 504 may further comprise a hydrophobic mesh 507 (corresponding to that described with reference to Figure 1 ) arranged on a surface of the wick 509 between the wick 509 and the heater 505. When the hydrophobic mesh is included, the hydrophobic mesh 507 may be configured as the contact surface 510. That is, the fluid transfer element can 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 covering a surface of the wick 509 opposite the surface facing the liquid 521 in the liquid store 506. The hydrophobic nature of the mesh 507 causes the liquid that has passed through the mesh 507 to be repelled and form droplets on the surface of the mesh 507 (as illustrated in Figure 3) rather than soaking back through the mesh 507 into the wick 509.

In the example of Figure 5, the compressing element 503 is an elongate rod or piston arranged to pass through a ring-shaped 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 separated from the fluid transfer element 504 (as shown in Figure 5A) to a position wherein the elongate rod is in contact with and is deforming the contact surface 510 of the fluid transfer element 504, thereby compressing the fluid transfer element 504 (as shown in Figure 5B). That is, the driver drives the compressing 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 the driver are powered by a power supply, such as a battery, within the main body of the electronic cigarette. In other examples, the compressing element 503 can be of any other shape suitable for movement into and out of contact with the fluid transfer element 504 whilst being in close proximity to the heater 505.

When the compressing element 503 pushes against the contact surface 510 of the fluid transfer element 504, the applied compression 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 liquid 513 held in the wick 509 to be released, as shown in Figure 5B. In embodiments including the hydrophobic mesh 507 as the contact surface 510, the liquid held in the wick 509 is released through the hydrophobic mesh 507. The heater 505 is arranged such that a surface of the heater 505 is within a close proximity to the contact surface 510 of the fluid transfer element 504 such that these droplets 515 are adsorbed onto the heater 505 by way of a fluid bridge thereby wetting the heater 505 surface, as shown in Figure 5C. Optionally, the heater 505 can have hydrophilic properties to encourage the transfer of the liquid from the contact surface of the mesh 507 to the surface of the heater 505. The surface of the heater 505 can include a porous ceramic; capillary action provided by this material can aid the transfer of the released liquid 513 to the heater 505.

The compressing element 503 then retracts from the contact surface 510 of the fluid transfer element 504. The removal of the compression causes the fluid transfer element 504 to return to its non-compressed state and in doing so the wick 509 draws in more liquid from the liquid store 506.

Power is supplied to the heater 505 by a power supply such as a battery in the electronic cigarette. When the liquid 515 is adsorbed on the heater 505 surface, the heater 505 applies thermal energy to the adsorbed liquid 515; this transfer of thermal energy to the adsorbed liquid 515 elevates the temperature of the adsorbed liquid 515 such that the adsorbed liquid 515 is vaporised and a vapour is generated. This vapour can then be inhaled by the user of the electronic cigarette through a mouthpiece.

Similarly to that described with reference to Figures 2A to 2E, the compressing element 503 can oscillate back and forth from being in contact with and deforming the contact surface 510 of the fluid transfer element 504 to being separated from the fluid transfer element 504. In this way, the vaporiser 502 operation repeatedly cycles through the compression-adsorption-retraction- vaporisation cycle.

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

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

In a similar and closely related alternative arrangement to that described with reference to Figure 5, the contact surface of the fluid transfer element is in contact with the heater when the compressing element is in the first position. The compressing element moves to the second position, deforming the contact surface and compressing the wick such that the contact surface moves away from the heater, thus creating a distance between the contact surface and the heater. This compression releases liquid held in the wick through the contact surface such that a fluid bridge is formed by the released liquid and the liquid is adsorbed onto the surface of the heater. The heater then heats and vaporises the adsorbed liquid. The compressing element retracts from the contact surface and returns to the first position. The deformation of the contact surface and compression to the wick is released such that the contact surface again contacts the heater. The application and release of the compression to the wick as the compressing element moves between the first and second positions provides a pumping action which can draw further liquid into the wick from the liquid store. Where suitable, all features described with reference to Figure 5 can be used with this arrangement.

Figures 6A and 6B show another embodiment of a cartridge 61 1 suitable for use with the heater as described with reference to Figures 1 , 2 and 5; Figures 7A and 7B show exploded diagrams of such a cartridge 611. The cartridge 611 includes the wick components of the vaporiser. The cartridge 61 1 is configured to be inserted into the electronic cigarette such that the fluid transfer element 604 of the cartridge is arranged with the heater of the electronic cigarette to form a vaporiser, such as that described with reference to Figures 1 , 2 and 5

The cartridge 61 1 has a housing 641 defining a liquid store 606; the housing 641 is substantially cylindrical in shape with one open end. Whilst the example is described as cylindrical, any other suitable shaped can be used.

A plug 627 is positioned in the open end of the housing 641 ; the plug 627 having an outer diameter approximately equal to the inner diameter of the housing 641 such that a snug fit is achieved. The plug 627 has a cavity 649 defined by sidewalls 645 adjacent to the walls of the housing 641 and a bottom wall 647, perpendicular to the sidewalls, arranged at an end of the plug inward to the housing 641 of the cartridge 61 1. The end of the plug 627 opposite the bottom wall 647 of the plug 627 has an outwardly extending flange portion 643 with an outer diameter greater than then inner diameter of the housing 641. This provides an abutment against the open end of the housing 641 forming a stopping point for the plug 627 as it slides into the housing 641 , and prevents the plug 627 sliding beyond the stopping point further into the housing 641. A wick 609 is contained within the cavity 649 and dimensioned to substantially fill the cavity 649. The bottom wall 647 of the plug 627 has a series of openings such that liquid held within the liquid store 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 flow channels 631 in the longitudinal direction of the cartridge. The plates 629 thus define a series of channels 631 running from the liquid store 606 into the cavity 649 of the plug 627. The plates 629 extend outwardly from the plug 627 and into the liquid store 606. These channels 631 are dimensioned such that they provide a capillary action drawing liquid from the liquid store 606 into the cavity 649, acting as a liquid buffer, for absorption by the wick 609. In this example, the combination of the channels 631 between the plate-like extensions 629 and the wick 609 constitute the fluid transfer element 604. As will be described subsequently, the fluid transfer element 604 can further include a hydrophobic mesh 607 (corresponding to that described with reference to Figure 1 ). In use, when the fluid transfer element 604 is compressed and subsequently released, liquid is drawn into the channels 631. This provides a pumping action, transporting liquid from the liquid store 606 to the space defined between the plates 629 forming the channels 631. The space between the thus provides a reservoir of liquid or buffer that is held in the proximity of the fluid transfer element. This ensures the supply of liquid to the fluid transfer element 604 and reduces the risk that the fluid transfer element 604 would become short of liquid.

The wick 609 is compressed by deforming a contact surface 610 that faces outwardly to the cartridge such that when compressed a portion of 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.

A surface of the wick 609 facing outwardly from the cartridge 611 can form the 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 arranged on the surface of the wick 609 facing outwardly from the cartridge 611. When the hydrophobic mesh 609 is included, the hydrophobic mesh 507 may be configured as the contact surface 510. The hydrophobic properties of the mesh 607 provide two main functions. Firstly, the hydrophobic properties prevent liquid stored in the wick 609 escaping through the mesh 607 when the wick 609 and mesh 607 are not being compressed. Secondly, when liquid passes through the mesh 607 following compression, the hydrophobic properties cause liquid to form into droplets on the surface of the mesh 607, rather than passing back through the mesh 607. In this way, the droplets can be adsorbed onto a heater.

In some examples, the cartridge 61 1 is a disposable consumable, to be replaced following the depletion of the liquid stored in the cartridge. The expired cartridge 61 1 is removed from the electronic cigarette, and a fresh cartridge 611 filled with liquid is inserted to the electronic cigarette.

The use of the cartridge 611 described with reference to Figures 6 and 7 provides similar power saving advantages to those described with respect to Figures 1 and 2 in that it provides for a smaller portion of liquid to be extracted for heating, rather than heating a larger volume of liquid in a liquid tank to generate a vapour.

In other examples, the cartridge 611 is reusable and can be refilled. For example, the plug 627 can be removed from the housing 641 so that additional liquid can be added. The plug can then be refitted and the cartridge can be reconnected to the electronic cigarette.

Figures 8A and 8B show cross-sectional diagrams of other embodiments of a vaporiser system 800 for an electronic cigarette. Similar to the previously described embodiments, the system in Figures 8a and 8b is configured to provide dosing capabilities and to avoid that the heater 805 transfers heat to the liquid store or cartridge 81 1. As illustrated, the vaporiser system 800 comprises a liquid store or cartridge 81 1 in a seating 890 in a housing 829 of the main body of the electronic cigarette, a fluid transfer component 804 and a heater 805. The liquid store or cartridge 81 1 , the fluid transfer component 804 and the heater are configured as separable parts. Rather than being housed in the cartridge 81 1 , the fluid transfer component 804 can be a separate component and comprises a chamber 855, a fluid transfer element 857, a piercing member 833 and fluid transfer surface (or heater contact surface) 810. The separate parts of the vaporiser system enable the liquid store to have a simple structure, which makes it easy to produce.

The fluid transfer component 804 has a shape corresponding to the contact area of the heater 805. The fluid transfer component 804 can be disc shaped with a piercing member 833 extending from one face arranged to be in a direction toward the cartridge 811 or cartridge seating 890 in the electronic cigarette. As illustrated in Figure 8A, the fluid transfer component 804 can be removably attached to the housing 839 of the main of the electronic cigarette. As illustrated in Figure 8B, the fluid transfer component 804 can be solely attached to the liquid store or cartridge 81 1. Optionally, the two parts of the housing 829, 839 can be separated to allow a user of the electronic cigarette to access, and remove or replace, the fluid transfer component 804.

The piercing member 833 is preferably in the shape of an elongate tube with a pointed end 835 and is arranged to pierce into a cartridge or liquid store 81 1 and contact liquid within a liquid store of the cartridge 811. A channel 837 runs through the elongate spike to draw the liquid through to the disc-shaped portion of the fluid transfer component. The piercing member 833 connects the electronic cigarette to the cartridge 81 1 and provides a fluid connection between the main body 839 of the electronic cigarette and the liquid store of the cartridge 81 1. The piercing member 833 forms a sealed connection to the cartridge 811 by way a friction fit to prevent leakage. Optionally the cartridge 811 has a recess 851 in a surface arranged to engage the piercing element such that the piercing element is guided to the correct area on the cartridge 81 1. The cartridge 811 is preferably made from a plastic material, with suitable rigidity to store a vaporisable liquid, whilst being suitably thin to be pierced with the piercing member 833. In an alternate example, the piercing member 833 can be replaced by a tube arranged to be received in the cartridge 81 1. In such an example, the cartridge may have a tear-off seal; when the seal is teared off, an opening in the cartridge is exposed into which the tube is received. The tube can form a sealed connection to the cartridge by way of a friction fit in the opening to prevent leakage.

The disc shaped portion of the fluid transfer component 804 comprises the fluid transfer element 857 and chamber 855. A first side of the fluid transfer element 857 faces the chamber 855, the chamber being between the fluid transfer element 857 and the elongate spike, and in fluid connection with the channel 837 running through the elongate spike, and a second side opposite the first side being the contact surface 810.

The fluid transfer component 804 is arranged inside the electronic cigarette 800 with a heater 805. The heater 805 can 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 an compressing element 803, as described with respect to Figures 1 and 2. Alternatively the heater 805 can be held at a fixed distance from the fluid transfer surface 810 and deformed with a separate compressing element 853, for example a piston or elongate rod, as described with reference to Figure 5. In both cases, the deformation applied to the fluid transfer surface 810 releases a liquid through the fluid transfer surface 810 which is adsorbed onto the heater 805 and vaporised. The surface of the heater 805 can include a porous ceramic; capillary action provided by this material can aid the transfer of the released liquid to the heater 805.

In some embodiments, the fluid transfer element 857 is a wick 809 which wicks liquid from the chamber 855 received through the channel 837, and the fluid transfer surface 810 (or contact surface 810) is the surface of the wick 809 arranged to face toward the heater. Optionally, the fluid transfer element can further include a hydrophobic mesh 807 (corresponding to that described with reference to Figure 1) covering the surface of the wick 809 arranged to face toward the heater. When the hydrophobic mesh 807 is included, the hydrophobic mesh 807 forms the fluid transfer surface 810 (or contact surface 810) of the fluid transfer element 857. Upon compression of the wick 809, by deforming the fluid transfer surface 810, liquid stored in the wick 809 is released from the fluid transfer surface 810 and adsorbed on the heater. When the hydrophobic mesh 807 is included, the released liquid passes through the hydrophobic mesh 807 forming droplets on the surface of the hydrophobic mesh 807 which are adsorbed onto the heater.

In use, the cartridge 81 1 is inserted into the electronic cigarette and pierced by the piercing member 833. Liquid in the cartridge 81 1 is drawn to the wick 809, through the piercing member 833 by, for example, capillary action and/or a pumping due to the compression and decompressions of the wick 809. The heater 805 or compressing element 853 deforms the contact surface 810 (that is the surface of the wick 809 or the hydrophobic mesh 807 if included) and compresses the wick 809, releasing liquid stored in the wick 809. If the hydrophobic mesh 807 is included the liquid is released through hydrophobic mesh 807, from the wick 809, 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 generate a vapour. The generated vapour can then be inhaled by the user through a mouthpiece of the electronic cigarette. When the liquid content in the cartridge 811 has been drained, the cartridge 81 1 can be removed from the piercing member 833 and replaced with a new cartridge 81 1 , or a refilled cartridge, storing a fresh supply of vaporisable liquid.

The example described with respect to Figure 8 provides the same advantages as those described with reference to Figures 1 , 2 and 5 in that only the portion of liquid absorbed on the heater need be heater to its vaporisation point. This requires less energy than heating a larger volume of liquid, for example held in a liquid tank, to its vaporisation point. As such, these power savings in heating lead to a longer battery life in the electronic cigarette. Furthermore, the separation of the heater and the liquid store prevents heat spreading through the liquid store which would further waste energy.

It will be understood to the skilled person that features from the various examples described herein can be readily substituted with one another throughout the embodiments, where appropriate.