FIELD OF THE INVENTION

The present invention relates to a mouthpiece for use with an aerosol generating device.

BACKGROUND

It is a developing field of interest to produce electronic cigarette devices that heat, but do not bum, a solid or semi-solid aerosol forming substrate which comprises tobacco. These devices typically receive a rod of tobacco in a heating chamber. The rod is heated by a heater to release an aerosol which can be inhaled by a user, typically from a mouthpiece. An issue present with these devices is that heat from the heater can also heat other components of the device, such as the mouthpiece. In devices that are compact in structure this can be disadvantageous because the temperature of outer components of the device, such as the mouthpiece, can become unacceptably high during operation of the device.

It is an object of the present invention to provide a mouthpiece for use with an aerosol generating device that addresses these requirements.

SUMMARY OF INVENTION

According to an aspect of the present invention there is provided a mouthpiece for use with an aerosol generating device, comprising: a cavity configured to receive a consumable; a mouthpiece structure comprising an internal wall that is configured to support the consumable at one of its ends when it is received in the cavity, wherein the internal wall of the mouthpiece has a tapered portion to provide an air gap between the tapered portion of the internal wall and the consumable along at least a portion of the length of the consumable when the consumable is received in the cavity.

In this way, the consumable can make contact only with a small surface area of the internal wall of the mouthpiece, thereby reducing thermal conduction between the consumable and the mouthpiece. This can provide a mouthpiece that has improved thermal insulation between the heat generated by a heater and an outer surface with which a user can come into contact. The angle at which the tapered portion is tapered may be constant along the length of the tapered portion. The air gap may be larger at the end of the mouthpiece located closer to the heater, and smaller at the end of the mouthpiece that supports the consumable. This can increase the insulating effect at regions that are closer to the heater, where the temperature of the consumable is likely to be highest.

Preferably, the angle at which the tapered portion of the internal wall is tapered is between 1 degree and 30 degrees. This may be the angle that is subtended by the tapered internal wall and the outer surface of the consumable, when present. This can provide a small angular taper that can establish the air gap at positions that are separated from the position at which the consumable is in contact with the internal wall.

Preferably, the internal wall comprises a gripping portion that is shaped to support the consumable wherein the gripping portion has a length that is between 0.1 mm and 10mm.

In this way, the consumable can be held securely within the mouthpiece when it is received. The length of the gripping portion in a longitudinal direction of the mouthpiece is designed to be short in order to minimise thermal conduction. In a transverse direction of the mouthpiece the length of the gripping portion may be greater than that in the longitudinal direction to increase the stability of the consumable when held in the mouthpiece.

Preferably, the length of the gripping portion is between 1 mm and 5mm.

Preferably, the internal wall comprises an upper internal wall and a lower internal wall, wherein the upper internal wall and the lower internal wall are separated from one another by a distance, at the location of the gripping portion, that is matched to or is smaller than the consumable, thereby to provide a friction fit. In this way, the consumable may be held securely within the mouthpiece when it is received between the upper and lower internal walls. The consumable may be a flat-shaped article. This can allow the consumable to be pinched between the upper and lower internal walls when it is installed. The distance between the upper internal wall and the lower internal may be constant along their width.

Preferably, the gripping portion comprises two parallel surfaces, the two parallel surfaces defining an upper plane and a lower plane. Preferably respective air gaps are provided between the upper plane and an upper tapered portion of the internal wall and between the lower plane and a lower tapered portion of the internal wall. In practice the upper plane and the lower plane may be coincident with planar surfaces of the consumable, when the consumable is present.

The mouthpiece may comprise an airflow channel that is provided, in use, between the consumable and an opening through which the user can inhale. The airflow channel preferably comprises upper and lower internal walls that comprise parallel surfaces that are not tapered. The upper and lower internal walls of the airflow channel define respective planes that can be extended to positions where a consumable may be located. Air gaps are preferably provided at positions between the upper and lower tapered portions of the internal wall, and the upper and lower planes that are parallel to the upper and lower internal walls of the airflow channel.

Preferably, the end of the gripping portion is defined by an abutment lip against which the consumable abuts when it is received in the cavity. In this way, the consumable can be held securely in place within the mouthpiece.

The height of the airflow channel is preferably less than the height of the gripping portion. In other words, the upper and lower internal walls of the airflow channel preferably have a separation that is less than the upper plane and the lower plane defined by the gripping portion. At least one of the upper and lower internal walls may therefore comprise a step which defines the abutment lip. Preferably, the upper internal wall comprises a first tapered portion and the lower internal wall comprises a second tapered portion, wherein the angles at which the first and second tapered portions are tapered are equal. In this way, the insulating effects of the air gap may be provided equally for the upper and lower internal walls.

Preferably, the cavity comprises an opening configured to enable a user to inhale an aerosol therefrom. In this way, the user may inhale the aerosol produced from the consumable when it is heated after it is received in the cavity.

According to another aspect of the present invention there is provided an aerosol generating device comprising the mouthpiece defined above and a main body that comprises a heater.

Preferably, a consumable is received in the cavity so that it can be heated by the heater to generate an aerosol.

BRIEF DESCRIPTION OF DRAWINGS

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

Figure 1 is a schematic diagram of a mouthpiece for use with an aerosol generating device in an embodiment of the invention;

Figure 2 is a schematic cross-sectional diagram of a mouthpiece for use with an aerosol generating device in an embodiment of the invention;

Figure 3 is a perspective cross-sectional diagram of a mouthpiece for use with an aerosol generating device in an embodiment of the invention;

Figure 4 is a schematic cross-sectional diagram of a mouthpiece for use with an aerosol generating device in an alternative embodiment of the invention. DETAILED DESCRIPTION

Figure 1 is a schematic diagram of a mouthpiece 2 for use with an aerosol generating device 100 in an embodiment of the invention. The mouthpiece 2 comprises a protrusion 3 that extends from the main body of the mouthpiece 2. The protrusion 3 comprises an opening 4 from which a user may inhale an aerosol produced by the device 100. One or more air inlets 101 are provided within the mouthpiece 2 that are fluidly connected to a heating chamber (not shown) of the device 100.

The mouthpiece 2 is suitably shaped such that a user may place their lips around the protrusion 3. The mouthpiece 2 and/or protrusion 3 preferably comprise a material or materials that are generally resistive to thermal conduction (PEEK, for example).

The mouthpiece 2 is securely attached to the main body of the aerosol generating device 100. The mouthpiece 2 and the aerosol generating device 100 may be constructed as a single unitary component. Alternatively, the mouthpiece 2 may be removably affixable to the aerosol generating device 100. In a further arrangement, the protrusion 3 can be removably affixable to the main body of the mouthpiece 2.

Figures 2 to 4 are schematic cross-sectional diagrams of a mouthpiece 2 for use with an aerosol generating device 100 in embodiments of the invention. Figures 2 and 3 depict an embodiment of the invention from different perspectives, with a consumable 6 provided within. In Figure 4 the mouthpiece 2 is depicted separately from the aerosol generating device 100, without a consumable 6 present.

The mouthpiece 2 comprises a cavity 5 that is configured to receive a consumable 6. In the embodiments of Figures 2 and 3, the consumable 6 is provided within the cavity 5. The consumable 6 is configured to be heated by a heater 20 within the aerosol generating device 100 to produce an aerosol. The opening 4 is provided at an end of the cavity 5, preferably at the end furthest from the heater 20. The user can inhale the produced aerosol through the opening 4. Once it has been depleted the consumable 6 can be removed and replaced by a fresh item.

The protrusion 3 comprises an upper internal wall 10a and a lower internal wall 10b. The upper internal wall 10a comprises a first tapered portion 12a and the lower internal wall 10b comprises a second tapered portion 12b. The upper internal wall 10a and the lower internal wall 10b are symmetrically arranged, either side of the consumable 6 in the cavity 5.

The internal walls 10a, 10b also form the outer walls of the cavity 5. An air gap 14 is provided between the tapered portions 12a, 12b and the consumable 6, when it is received in the cavity 5. The air gap 14 is provided along at least a portion of the length of the consumable 6.

The internal walls 10a, 10b also comprise a gripping portion 16. The gripping portion 16 is shaped to support an end of the consumable 6 when it is received in the cavity 5. The upper internal wall 10a and the lower internal wall 10b each comprise an abutment lip 18 (which can be seen most clearly in Figure 4). The abutment lips 18 define an end of the gripping portion 16, against which the end of the consumable 6 can abut when it is installed in the cavity 5. The other end of the gripping portion 16 is at an end of the tapered portions 12a, 12b of the internal walls 10a. 10b. The upper internal wall 10a is separated from the lower internal wall 10b by a distance that is equal to or slightly smaller than the thickness of the consumable 6. This can allow one end of the consumable 6 to be pinched by the gripping portion 16 when it is installed in the cavity 5.

Figures 2 and 3 further depict a heater 20, which is configured to heat the consumable 6 to produce an aerosol. One or more air inlets (not shown) are preferably provided within the mouthpiece 2 that are fluidly connected with the cavity 5 (and therefore the consumable 6, when it is installed in the cavity 5). The heater 20 comprises two parallel heating plates that respectively heat two major surfaces of the consumable 6. The consumable 6 is generally shaped as a rectangular prism, having major surfaces that have planar shapes. The consumable 6 is elongate such that it extends from within the aerosol generating device 100 and fits inside the cavity 5. The consumable 6 can be installed adjacent the heater 20 so that it can be heated effectively.

The consumable 6 may comprise a tobacco substrate that may comprise shredded tobacco and which may be solid or semi-solid that can be heated without burning. In alternative scenarios the consumable 6 may comprise other kinds of substrate such as a vaporisable liquid substrate held in a reservoir.

The mouthpiece 2 optionally comprises one or more air inlets 101. The one or more air inlets 101 are in fluid communication with the cavity 5 such that the aerosol produced from the consumable can be inhaled by a user from the opening 4.

The tapered portions 12a, 12b are shaped to provide an air gap 14 between themselves and the consumable 6. The internal walls 10a, 10b are tapered from the end of the mouthpiece 2 closer to the heater 20 to the end of the mouthpiece 2 closest to the opening 4.

Preferably the tapered portions 12a, 12b are tapered at a tapering angle that is between 1 degree to 30 degrees. The tapering angle is that which is subtended by a line that is parallel to a longitudinal axis of the device and one of the tapered portions 12a, 12b. The tapering angle is preferably constant over the length of the tapered portions 12a, 12b. Alternatively, the tapering angle may not be constant over the length of the tapered portions 12a, 12b and the tapered portions 12a, 12b may have a substantially curved shape or another arbitrary shape. The tapered portions 12a, 12b preferably have a length in the direction of the longitudinal axis of the device that is at least half of the length of the protrusion 3 measured in the same direction.

The air gap 14 is provided between the internal walls 10a, 10b and the consumable 6 to provide thermal insulation. More specifically, the air gap 14 is provided between the internal walls 10a, 10b and the consumable 6 in order to provide thermal insulation between heat generated by the heater 20 and the mouthpiece 2, and therefore the user. The air gap 14 surrounds the portion of the consumable 6 that is unsupported by the internal walls 10a, 10b when it is received in the cavity 5. The consumable 6 is heated by the heater 20 and as such the consumable 6 can conduct heat to the mouthpiece 2 only at points where the two make contact. The presence of the tapered portions 12a, 12b and the air gap 14 means that there only a small point of contact between the internal wall 10a, 10b and the consumable 6 when the consumable is received in the cavity 5 (at the location of the gripping portion 16).

As the tapered portions 12a, 12b are tapered from the end of the mouthpiece 2 closer to the heater 20 toward the end of the mouthpiece 2 closer to the opening 4, the air gap 14 is largest in cross section at the end of the cavity 5 closest to the heater 20 at which point the temperature of the consumable 6 is at its highest.

The first 12a and second 12b tapered portions are tapered at the same angle. The insulating effect of the air gap 14 is therefore equal over the surfaces of the upper internal wall 10a and the lower internal wall 10b.

The gripping portion 16 is shaped to support the consumable 6 at one of its ends. The length of the gripping portion 16 in the direction of the longitudinal axis of the device 100 is between 0.1 mm and 10mm. Preferably, the length of the gripping portion 16 in the direction of the longitudinal axis of the device is between 1 mm and 5mm. At the location of the gripping portion 16 the upper internal wall 10a and the lower internal wall 10b may be separated by a distance that is matched to or is smaller than the consumable 6 thereby to provide a friction fit. The surfaces of the gripping portion 16 on the upper 10a and lower 10b internal walls are substantially parallel. The gripping portion 16 therefore pinches an end of the consumable 6, supporting it securely within the cavity 5.

The gripping portion 16 is configured to support the consumable 6 substantially across its full width, but only over a portion of its length, for example 0.1 mm to 10mm. The surfaces of the gripping portion 16 have a small total surface area and therefore only make contact with a small portion of the surface area of the consumable 6; this means that less heat is conducted through the point of contact.

The end of the gripping portion 16 is defined by the abutment lips 18 against which the consumable 6 abuts when it is received in the cavity 5. Two abutment lips 18 are provided, one on each of the upper 10a and lower 10b internal walls. The abutment lips 18 are shaped such that the consumable is prevented from advancing past the abutment lips 18 towards the opening 4.

The upper and lower internal walls 10a, b each comprise four distinct surfaces. At a proximal end of the mouthpiece, the upper and lower internal walls 10a, b define an airflow channel between the opening 4 and the abutment lip 18. The airflow channel defines a first plane and a second plane. The first and second planes are separated from each other by a short distance. Respective air gaps 14 are provided at positions that are between the first and second planes and the upper and lower tapered portions of the internal wall.

At a medial section of the mouthpiece, the upper and lower internal walls 10a, b each comprise a surface defining an abutment lip 18, which is provided perpendicular to the surfaces defining the first and second planes.

At the medial section of the mouthpiece, the upper and lower internal walls 10a, b also comprise surfaces defining the gripping portion 16. The surfaces defining the gripping portion 16 are separated from each other by a greater distance than that of the surfaces of the upper and lower internal walls 10a, b defining the airflow channel. The surfaces of the gripping portion 16 define an upper plane and a lower plane. The upper plane corresponds to the upper wall 10a, and the lower plane corresponds to the lower wall 10b. The upper and lower planes are coincident with the planar surfaces of the consumable 6, when present. In this way, the air gap 14 is provided between the upper and lower planes, which are parallel with surfaces of the gripping portion 16.

In embodiments of the invention which include an abutment lip 18, the distance between the first and second planes is less than that between the upper and lower planes. In embodiments of the invention which do not include an abutment lip, the first plane and the upper plane, and the second plane and the lower plane, are one and the same. The airflow channel extends from the opening to the gripping portion 16 in such embodiments. At a distal end of the mouthpiece, the upper and lower internal walls 10a, b additionally each comprise a surface corresponding to a tapered portion. The surfaces of the tapered portions 12a, b extend from the distal end of the mouthpiece to the surfaces of the gripping portion 16.