Capsule for use with an electronic smoking device

Abstract

A capsule (6) for use with an electronic smoking device (1) is provided where liquid for atomisation by an electric atomiser is contained within a cavity enclosed by an end wall (50); a lateral wall (50); and a puncturable membrane (34). One or more grooves (54) are provided on the inner face (52) of the lateral wall (50) adjacent the cavity. When the puncturable membrane (34) is punctured the one or more grooves (54) act to provide air channels adjacent the lateral wall (50) facilitating air to pass into the cavity as the liquid leaves the cavity via the puncture in the puncturable membrane (34).

Claims

1. An electronic smoking device, comprising: a housing, an electric power source in the housing, an electrically heatable atomizer adapted to atomize a liquid supplied from a capsule, and an interface adapted to mount the capsule to the electronic smoking device; the capsule comprising a shell having a closed off first end and an open second end; a puncturable membrane closing off the open second end and the liquid contained within the shell, the shell having one or more grooves on an inside surface of the shell; wherein when the capsule is mounted to the electronic smoking device, the puncturable membrane is punctured by a liquid conductor of the electronic smoking device and the one or more grooves provide air channels allowing air to pass into the capsule as the liquid moves out of the capsule via the liquid conductor.

2. The electronic smoking device of claim 1 wherein the liquid conductor has a free end provided with a piercing tip and a wick adapted to conduct the liquid from the capsule to the atomizer after the membrane of the capsule has been punctured by the piercing tip.

3. The electronic smoking device of claim 1 with the shell having a cylindrical section adjacent to the open end of the shell.

4. The electronic smoking device of claim 1 with the shell having a smooth interior area adjacent to the open end of the shell.

5. The electronic smoking device of claim 1 having a circular groove in an end wall, the circular groove interconnecting with the one or more grooves.

6. The electronic smoking device of claim 1 wherein the shell is rigid and tubular.

7. The electronic smoking device of claim 1 wherein the one or more grooves are equally spaced apart.

8. The electronic smoking device of claim 1 having at least three grooves.

9. The electronic smoking device of claim 1 wherein one or more of the grooves has a triangular, quadrangular, and/or a semi-circular cross-sectional shape.

10. The electronic smoking device of claim 1 wherein the shell comprises a hydrophobic material.

11. The electronic smoking device of claim 1 wherein the liquid is hydrophilic.

12. The electronic smoking device of claim 1 wherein the shell comprises a step between an end section and a center section of the shell, and the shell has different cross-sectional shapes on either side of the step.

13. The electronic smoking device of claim 1 wherein the capsule has a length of 20 mm to 26 mm and an inner diameter in the range of from 2.5 mm to 4.0 mm.

14. A capsule for use with an electronic smoking device, comprising: an elongated tubular rigid shell having a closed off first end and an open second end; a puncturable membrane closing off the open second end; a liquid contained within the shell; the shell having one or more grooves extending longitudinally on an inside surface of the shell.

15. The capsule of claim 14 with the shell having a cylindrical section adjacent to the open end of the shell.

16. The capsule of claim 14 with the shell having a smooth interior area adjacent to the open end of the shell.

17. A capsule for use with an electronic smoking device, comprising: an elongated tubular rigid shell having a closed off first end and an open second end, the shell having an outer cylindrical section adjacent to the open end of the shell, and the shell having a smooth interior area adjacent to the open end of the shell; a puncturable membrane closing off the open second end; a liquid contained within the shell; the shell having one or more grooves extending longitudinally on an inside surface of the shell, between the closed off first end and the smooth interior area, the smooth interior area between the puncturable membrane and the one or more grooves.

Description

(1) In the following, the invention is further described by means of an embodiment. The drawings show in

(2) FIG. 1 a schematic longitudinal section through an embodiment of the system according to the invention, which displays part of an electronic smoking device and a capsule mounted therein,

(3) FIG. 2 a schematic longitudinal section through the capsule,

(4) FIG. 3 a schematic longitudinal view of the shell of the capsule,

(5) FIG. 4 an end view of the shell, viewed from the open end of the shell, and

(6) FIG. 5 a three-dimensional view of the shell.

(7) FIG. 1 illustrates an embodiment of an electronic smoking device in a schematic longitudinal section. The electronic smoking device, designated by reference numeral 1, comprises a housing which, in the embodiment, includes two sections, the section called atomizer section 2 and the section called battery section 3. An end cap 4 connected to the atomizer section 2 encloses a capsule 6 containing a liquid. The capsule 6, which will be explained in more detail by means of FIGS. 2 to 5, is held in place by a cylindrical pipe 8 extending away from the atomizer section 2 of the smoking device 1.

(8) The battery section 3 of the housing is not shown in detail. It accommodates a rechargeable battery as an electric power source and control electronics for controlling the electronic smoking device 1, including a puff sensor detecting when a user inhales at the end cap 4, which causes the control electronics to close an electrical circuit so that an electrical current is supplied to a heatable atomizer arranged in the atomizer section 2 of the housing. For providing mechanical support and electrical contact, a female thread 10 and a pole 12 isolated therefrom are arranged in the end area of the battery section 3 shown in FIG. 1. The female thread 10 is connected to ground of the battery, the pole 12 is connected to the control electronics which serves as a switch for powering pole 12 on demand, i.e. when a puff is detected.

(9) The end of the atomizer section 2 of the housing comprises a male thread 14 for providing connection to ground and another pole 16 which is pressed against pole 12 when the male thread 14 is threaded into the female thread 10, see FIG. 1.

(10) In the embodiment, the atomizer comprises a cylindrical support 20 made of ceramics, which holds a bracket 22 of stainless steel. The support 20 and the bracket 22 are surrounded by an arrangement of metal filaments, e.g. a nickel wire structure, which serves as a wick 24. The interior space of the support 20 and the wick material can be heated by means of a heating wire 26 made of, e.g., a nickel chromium alloy.

(11) The capsule 6 comprises a shell 30 having an open end 32 sealed by a puncturable membrane 34 and a closed end 36. In the embodiment, the shell 30 and the closed end 36 of the shell 30 are made in one piece by injection-moulding from polypropylene material. The membrane 34 includes an aluminium film which is heat-sealed to the shell 30. In the embodiment, an aerosol-forming liquid (see below) is contained within the cavity enclosed by the shell 30 and the puncturable membrane with the liquid freely flowing within the cavity without the cavity containing a sponge-like material like cotton for soaking up the liquid.

(12) When the shell 30 is inserted into the pipe 8, a piercing spike mounted at the end of the bracket 22 (not shown in the figures) punctures the membrane 34 and the wick 24 enters into the interior of the capsule 6. When the wick 24 enters the interior of the capsule 6, the liquid contained in the capsule 6 is drawn by capillary action from within the capsule 6 and supplied to the atomizer, where it is caused to be distributed in the wick material about the support 20. In this way, the liquid can be easily heated by means of the heating wire 26 in order to be atomized and to form an aerosol.

(13) In the embodiment, the shell 30 of the capsule 6 consists of three sections, see the schematic longitudinal section shown in FIG. 2, i.e. an end section 40, which also includes the closed end 36 of the shell 30, a centre section 42, and a cylindrical section 44 adjacent to the open end 32 of the shell 30.

(14) In its end section 40, the shell 30 in this embodiment has a triangular-like cross-sectional shape (perpendicularly to its longitudinal axis). In the centre section 42 of the shell 30, the cross-sectional shape is also substantially triangular, but somewhat different in cross section to the end section 40. In this way, some steps 46 are formed in the zone where the end section 40 meets the centre section 42. These steps 46 serve as stops, which abut at an end face of the pipe 8 when the capsule 6 is inserted into the pipe 8, see FIG. 1. In the schematic representation of FIG. 1, the triangular symmetry of the capsule 6 is not correctly displayed. This symmetry, however, is evident from FIG. 4.

(15) FIG. 3 shows a schematic longitudinal view of the shell 30. The shell 30 comprises a lateral wall 50 and an end wall 51 at the closed end 36. FIG. 3 also displays part the inner face (designated by 52) of the lateral wall 50. The inner face 52 is provided with longitudinally extending grooves 54. As shown in FIGS. 4 and 5, the grooves 54 (in the embodiment a total of six) are symmetrically arranged and have an essentially triangular cross-sectional shape. At the end wall 51 of shell 30, the grooves 54 are interconnected by a generally circular groove 56, also having an essentially triangular cross-sectional shape. The grooves 54 do not extend up to the open end 32 of the shell 30 so that a smooth area 58 is left in this region.

(16) In the embodiment, the shell 30 has an outer length of about 23 mm. Preferred values for the outer length are in the range of from 20 mm to 26 mm or of from 22 mm to 24 mm. The inner diameter of the shell 30 is about 3.4 mm or somewhat smaller; it may vary. Preferred values for the inner diameter are in the range of from 2.5 mm to 4.0 mm or from 3.0 mm to 3.5 mm. The thickness of the lateral wall 50 of the shell 30 is not constant and varies between 0.8 mm to 1.6 mm. Preferred values for the thickness of the lateral wall are in the range of from 0.5 mm to 2.0 mm. The end wall 51 has a thickness comparable to that of the lateral wall 50. Generally, other dimensions of the shell 30 are conceivable as well.

(17) Moreover, in the embodiment, the grooves 54 have a length in the range of from 10 mm to 15 mm, a depth (measured perpendicularly with respect to the lateral wall 50) in the range of from 0.2 mm to 0.5 mm, and a width in the range of from 0.3 mm to 0.5 mm. Thus, the grooves 54 extend over about 40% to 80% of the inner length of the shell 30. The depth and width of the grooves 54 may be variable along the length of a given groove 54. Generally, other dimensions of the grooves 54 are conceivable as well.

(18) In the embodiment, the liquid in the capsule 6 contains water in a range of from 2% to 7%, glycerol in a range of from 15% to 25% and propylene glycol in a range of from 70% to 80%. The percentages are by weight, related to the total weight of the liquid. Other ingredients, like flavourants, may be contained as well. The viscosity of the liquid is in the range of from, e.g., 55 mm.sup.2/s to 75 mm.sup.2/s. This liquid is hydrophilic and has a rather high viscosity.

(19) As already mentioned, in this embodiment the shell 30 is made of a polypropylene material, which is hydrophobic. Therefore, the hydrophilic liquid in the capsule 6 does not wet the inner face 52 of the lateral wall 50. The corresponding liquid/solid surface tension results in a significant curvature of the liquid in the neighbourhood of the grooves 54, 56 so that the liquid generally does not fill the grooves 54, 56. After the membrane 34 has been pierced, the grooves serve as air channels distributing the air within the capsule 6 and facilitating a pressure relief when liquid is conducted out of the capsule 6 by means of wick 24.

(20) In this embodiment the grooves 54, 56 do not extend into the smooth area 58 adjacent the pierced membrane 34. It is not necessary for the groove 54, 56 to extend into this area since as the smooth area is adjacent the pierced membrane 34 it is relatively easy for air to enter into this portion of the capsule 6, so that the absence of grooves in the smooth area 58 is not critical. Because of the pressure relief provided by air channels created by the grooves 54, 56, an unimpeded and continuous flow of the liquid out of the capsule 6 is largely facilitated.

(21) When using the electronic smoking device 1, a consumer (user) removes the end cap 4 from the atomizer section 2 of the housing and inserts a fresh capsule 6 into the pipe 8 so that the spike mounted at the bracket 22 penetrates the membrane 34. In this state, the capsule 6 is secured by frictional forces between the bracket 22 (including the material of the wick 24) and the rest of the membrane 34. The wick 24 then distributes the liquid contents of the capsule 6 in the area of the atomizer so that it can be atomized when the control electronics actuates the heating wire 26. The triangular cross section of the capsule 6 compared with the circular cross section of the pipe 8 ensures that there is some free space provided inbetween the centre section 42 of the shell 30 and the inner face of the pipe 8. Another free space 64 is provided within the end cap 4, because the end cap 4 does not contact the capsule 6, see FIG. 1. Thus when the liquid within the wick 24 is atomized by the atomizer and an aerosol is generated, the aerosol can be inhaled by a user sucking on the end cap 4.

(22) In its end area, the end cap 4 is designed as a mouthpiece 70 having a suction hole (not shown in FIG. 1). The puff detector mentioned above senses when the consumer inhales at this suction hole, which initiates the heating step described before. The end cap 4 comprises resilient protrusions 72 engaged in recesses 74 provided at the atomizer section 2 of the housing, which holds the end cap 4 in a detachable manner. When the capsule 6 is empty, the consumer can detach the end cap 4 and remove the capsule 6 from the pipe 8.