HK1214740B - Electronic cigarette - Google Patents

Description

This invention relates to an electronic cigarette. Document US 2011/0303231 A1 discloses a prior art atomizing device for electronic cigarette. Embodiments of electronic cigarette described herein comprise a generally cylindrical housing with a proximal mouth end and a distal end, and within the housing: a vaporiser to produce vapour to be delivered to the mouth end, a battery, and sensor circuitry to detect a user drawing on the mouth end and to connect the battery to power the vaporiser to produce vapour, the vaporiser comprising: a tube having inlet and outlet ends and extending longitudinally of the housing, supports at opposite ends of the tube for directing airflow into and out of the tube from the inlet to the outlet, a porous matrix containing a vaporisable liquid extending around the tube, wicking fibres extending through side openings in the tube and configured to wick the vaporisable liquid from the porous matrix into the tube, and an electrical heater coil in the tube configured to be powered by the battery to vaporise liquid on the wicking fibres in the tube, so that vapour is supplied along the tube to the outlet end when the user draws thereon, wherein the wicking fibres are wrapped around the outer surface of the tube so as to contact and receive the vaporisable liquid by capilliary action from the matrix.

The wicking fibres may be wrapped around the tube in a spiral pattern. The wicking fibres may extend towards the inlet or the outlet end of the tube or both ends.

Furthermore, the wicking fibres may emanate from at least one of the side openings in first and second bundles which are wrapped in different wrapping patterns around the tube, for example in different directions and/or with different hands.

The supports for the tube may include a mouth end stopper that is push-fitted into the mouth end of the housing, which includes a mouthpiece spigot onto which the outlet end of the tube is received, and an outlet passageway extending through the spigot to provide an outlet for vapour from the tube.

Also, the supports for the tube may include an annular support member that includes a peripheral surface to engage with the interior of the housing, an inlet spigot on which the inlet end of the tube is mounted, and an inlet passageway extending through the inlet spigot to provide an inlet for air into the tube.

Embodiments of electronic cigarette will now be described in more detail by way of example with reference to the accompanying drawings, in which:

• Figure 1 is a schematic perspective view of an electronic cigarette;
• Figure 2 is a longitudinal section through the electronic cigarette shown in Figure 1;
• Figure 3 is an exploded, partial perspective view of the vaporiser illustrated in Figure 2, showing its heater element in a tube;
• Figure 4 is an enlarged portion of the sectional view shown in Figure 2 in the region of its heater element;
• Figures 5A and 5B illustrate alternative wrapping patterns for the wicking fibres around the tube; and
• Figure 6 is a schematic view of portions of an alternative embodiment of vaporiser.

Referring to Figures 1 and 2, an electronic cigarette 1 includes a generally cylindrical housing 2 conveniently in the form of a tube of plastics material that extends from a proximal or mouth end 3 to distal end 4. An end cap 5 of translucent plastics material is push-fitted into the distal end 4 and a mouth end stopper 6 is similarly fitted into the mouth end 3. The tube 2 is flexible and given rigidity in part by its internal components, as will be described in more detail hereinafter. The tube in one example is made of polypropylene.

As shown in Figure 2, the end cap 5 includes an air inlet 7 so that when the user draws on the mouth end 3, air is drawn into the housing 2 and vapour is supplied to the user through the mouth end 3 as will be described hereinafter.

The housing 2 contains a battery 8, sensor circuitry 9 and a vaporiser 10 that produces a vapour to be supplied to the user.

The vaporiser 10 is illustrated in more detail in Figures 3 and 4. The vaporiser includes a tube 11, conveniently made of fibreglass material which extends from an inlet end 12 to outlet end 13. The tube 11 includes diametrically opposed side openings 14a,b through which wicking fibres 15 extend, so as to extend diametrically across the interior of the tube 11 and lie along its outer surface 11a. The wicking fibres 15 are conveniently made of heat resistant material such as fibreglass. In the example shown in Figures 3, 4 and 5A, the fibres 15 are wrapped in a spiral pattern around the outer surface 11a of the tube 11 towards both its inlet end 12 and outlet end 13. In this example, fibres 15a extending out of side opening 14a are wound in a spiral towards the outlet end 13 and fibres 15b extending out of side opening 14b are wound in a spiral towards the inlet end 12, with the same hand as fibres 15a. However, other winding patterns can be used. For example as shown in Figure 5B, the fibres 15a, 15b are both wound in a spiral pattern towards the outlet end 13 of the tube 11, with opposite hands.

Other winding patterns can be used such as a serpentine pattern around the outer surface 11a of tube 11. Also the fibres 15a. and/or 15b could be divided into bunches and each wound differently around the tube 11, with the same or different winding patterns in the same or different directions along the tube 11, with the same or different hands.

The wrapping of the fibres 15 around the outer surface 11a of the tube improves the operation of the vaporiser 10, as will be explained in more detail hereinafter.

An electrical heater coil 16 extends diametrically across the tube 11, with the wicking fibres 15 passing axially within the coil 16. Electrical leads 17a, 17b supply electrical power to the coil 16 from the battery 8 under the control of the sensor circuitry 9 shown in Figure 2.

A porous matrix that comprises first and second sheets of fibrous material 18, 19 is loaded with a vaporisable material, for example a nicotine and glycerol solution.

The sheet 18 has a lower surface area and absorbency than the surrounding sheet 19 which can retain a larger volume of the liquid. Typically, the sheet 19 has a larger pore size than the sheet 18. The sheet 18 however facilitates transfer of the liquid to the wicking fibres 15 so that the liquid is wicked along the core of the heater coil 16.

One end of the vaporiser includes an annular support member 20 that has a peripheral surface 21 that engages with the interior surface of the cylindrical housing 2. The annular support member 20 has a generally circular end face 22 extending diametrically across the housing 2 from which an axial inlet spigot 23 extends towards the mouth end 3 and receives the inlet end 12 of tube 11. The overlying ends of the sheets 18, 19 are retained between an annular, depending flange 24 and the inlet spigot 23 at the inlet end of tube 11, and generally fill the space between the interior surface of housing 2 and the tube 11. The annular support member 20 is conveniently flexible and made of silicon for example, so that it can be easily manipulated into housing 2 during manufacture. The sheets 18, 19 are wrapped around the tube 11 and thereby locate the wicking fibres 15 along the length of the outer surface of the tube 11.

Spigot 23 includes a through hole to provide an air inlet passageway 23a into the tube 11.

A mouth end end stopper 6 includes a mouthpiece spigot 25 that receives the outlet end 13 of tube 11. The end stopper 6 includes an axial outlet passageway 26 through the spigot to pass vapour to a user through the mouth end 3 of housing 2. Also, the mouth end stopper 6 includes a depending flange 27 so that the stopper 6 can be push-fitted into the mouth end 3 of housing 2. The outlet end 13 of tube 11 may extend slightly beyond the matrix 18, 19. Thus there is a gap between the matrix and the mouth end 3 of the housing 2. Also, the mouthpiece spigot 25 which extends into the tube outlet end 13 is longer than the depending flange 27 that engages with the housing 2, so as to provide a gap between the porous matrix 18, 19 and the end stopper 6. This arrangement prevents or reduces leakage of the liquid held in the sheets 18, 19 through the mouth end 3 of the housing.

Thus, the annular support member 20 and the mouth end stopper 6 with their respective spigots 23, 25 cooperate with the tube 11 and the housing 2 to provide a closed plenum containing the porous sheets 18, 19 so as to retain the nicotine containing liquid in the sheets 18, 19 without leakage from the housing 2, and to allow the liquid to wick along wicking fibres 15 to be vaporised on operation of the heater coil 16.

An advantage of winding the fibres 15a, 15b around the outer surface 11a of the tube 11 for example in a spiral pattern, is that the wicking fibres receive the nicotine containing liquid from porous matrix layers 18,19 all around the circumference of the tube 11 rather than from just two longitudinal regions as would occur if the fibres run in a straight line longitudinally of the the outer surface of the tube 11. Thus a more reliable and complete transfer of the liquid to the wicking fibres 15 occurs by capilliary action from the matrix 18,19 as result of the fibre winding pattern.

A washer 28, conveniently made of rigid plastics material such as polypropylene, is provided between the vaporiser 10 and battery 8 to provide rigidity to the housing 2 in the region of the annular support member 20. The washer 28 includes an air passageway opening 29 and also openings 30 which receive the electrical leads 17a, 17b. The tubular housing 2 thus is relatively rigid to the touch of the user's fingers in the region of the battery 8 and the washer 28 but is more resilient to the touch in the region containing the vaporiser 10 to provide characteristics of tactility that are similar to those of a conventional tobacco containing cigarette.

An air passageway extends from the inlet opening 7 in the end cap 5 between the sensor circuitry 9 and battery 8 to the air passageway 29 in the washer 28 and thence to the inlet 12 of tube 11.

The sensor circuitry 9 may include a light source in the form of LED 31 which, when operated is visible through the translucent end cap 5.

When the user draws on the mouth end 3, air is drawn through the air inlet 7 in the direction of arrow A past the battery 8 and into the tube 11. The drawing action reduces the air pressure within the housing 2, which is sensed by the sensor circuitry 9. In response, electrical power from the battery 8 is switched by the sensor circuitry 9 to pass through leads 17a, 17b and energise heater coil 16. As a result, liquid which has been wicked by the wicking fibres 15 from the surrounding porous matrix layers 18, 19 is heated and thereby vaporised so that a stream of nicotine containing vapour is passed through the outlet passageway 26 for the user. Also, in response to the pressure reduction, the sensor circuitry illuminates the LED 31 to mimic the burning of a conventional tobacco containing cigarette.

Also, referring to Figures 3 and 4, atomisation apertures 32 are formed in the tube 11 so that when the user draws on the mouth end 3, the resulting pressure reduction in tube 11 draws liquid from the surrounding porous matrix layers 18, 19 through the apertures 32 and as a result, the liquid is atomised, thereby producing an atomised stream 33 shown in Figure 4. In this example, the atomisation apertures 32 are provided between the inlet end 12 of tube 11 and the heater coil 16 so that the atomised droplets 33 then pass the heater 16, which encourages further vaporisation of the atomised liquid.

Typically, the atomisation apertures 32 are of a diameter between 0.1-0.5mm. In the example of Figure 3, the atomisation apertures 32 are shown diametrically opposite one another but other configurations are possible, for example a distributed arrangement along the tube 11, which may be spatially uniform or otherwise. Also, one or more of apertures 32 may be provided downstream of the heater coil 16, towards the outlet end of the tube 11.

A modified arrangement is illustrated in Figure 6 with an alternative form of side openings to receive the wicking fibres 15. The coil 16 can be slid into an elongate slot 34 formed in tube 11 which is then closed by means of an overlying cylindrical sheath 35 that is conveniently is made of fibreglass material and slid into place from the outlet end 13 of tube 11. In this example, the wicking fibres 15b extend in a spiral towards the inlet opening 12 of tube 11, with the advantage that their ends can be sandwiched between the tube 11 and the porous matrix sheet, and held firmly between the region of the tube 11 on spigot 23 and the depending flange 24 of the annular support member 20.

In another modification, the device shown in Figure 1 and 2 may have a two part housing 2 so that the vaporiser 10 is attached to the battery 8 and sensor circuitry 9 by a releasable coupling (not shown) along hatched line X shown in Figure 2.

In order to address various issues and advance the art, the entirety of this disclosure shows by way of illustration various embodiments in which the claimed invention(s) may be practiced and provide for a superior electronic cigarette. The advantages and features of the disclosure are of a representative sample of embodiments only, and are not exhaustive and/or exclusive. They are presented only to assist in understanding and teach the claimed features. It is to be understood that advantages, embodiments, examples, functions, features, structures, and/or other aspects of the disclosure are not to be considered limitations on the disclosure as defined by the claims or limitations on equivalents to the claims, and that other embodiments may be utilised and modifications may be made without departing from the scope of the disclosure. Various embodiments may suitably comprise, consist of, or consist essentially of, various combinations of the disclosed elements, components, features, parts, steps, means, etc.

Claims (15)

1. An electronic cigarette (1) comprising a generally cylindrical housing (2) with a proximal mouth end (3) and a distal end (4), and within the housing:

   a vaporiser (10) to produce vapour to be delivered to the mouth end,

   a battery (8), and

   sensor circuitry (9) to detect a user drawing on the mouth end and connect the battery to power the vaporiser to produce vapour,

   the vaporiser comprising:

   a tube (11) having inlet (12) and outlet (13) ends and extending longitudinally of the housing, supports at opposite ends of the tube for directing airflow into and out of the tube from the inlet to the outlet,

   a porous matrix (18, 19) containing a vaporisable liquid extending around the tube, wicking fibres (15) extending through side openings (14a, 14b) in the tube and configured to wick the vaporisable liquid from the porous matrix into the tube, and

   an electrical heater coil (16) in the tube configured to be powered by the battery to vaporise liquid on the wicking fibres in the tube, so that vapour is supplied along the tube to the outlet end when the user draws thereon, characterized in that the wicking fibres are wrapped around the outer surface of the tube so as to contact and receive the vaporisable liquid, by capilliary action from the matrix.
2. An electronic cigarette according to claim 1 wherein the wicking fibres are wrapped around the tube in a spiral pattern.
3. An electronic cigarette according to claim 1 or 2 wherein at least one of the wrapped wicking fibres extends towards the inlet end of the tube and/or towards the outlet end of the tube.
4. An electronic cigarette according to any preceding claim wherein the wicking fibres emanating from at least one of the side openings is configured in first and second bundles which are wrapped in different wrapping patterns around the tube.
5. An electronic cigarette according to any preceding claim wherein the supports include a mouth end stopper (6) that is push-fitted into the mouth end of the housing, the mouth end stopper including a mouthpiece spigot (25) onto which the outlet end of the tube is received, and an outlet passageway (26) extending through the spigot to provide an outlet for vapour from the tube; and optionally including a gap between the porous matrix and the end stopper.
6. An electronic cigarette according to any preceding claim wherein the supports include an annular support member (20) including a peripheral surface (21) to engage with the interior of the housing, an inlet spigot (23) on which the inlet end of the tube is mounted, and an inlet passageway extending through the inlet spigot to provide an inlet for air into the tube; and optionally wherein the annular support member includes a depending peripheral flange (24) such that the porous matrix is retained between the tube on the spigot of the support member and the flange.
7. An electronic cigarette according to claim 6 wherein ends of the wicking fibres are retained sandwiched between the tube and the porous matrix between the spigot and the flange.
8. An electronic cigarette according to claim 6 or 7 including a washer (28) between the annular support member and the battery.
9. An electronic cigarette according to any preceding claim including an air inlet opening (7) at the distal, end of the housing; and optionally including an air feed passageway (29) between the battery and the housing, extending from the air inlet opening to the inlet end of the tube.
10. An electronic cigarette according to any preceding claim wherein the sensor circuitry is disposed between the battery and the distal end of the housing.
11. An electronic cigarette according to any preceding claim including a light source powered by the battery under the control of the sensor circuitry to be illuminated in response to the user drawing on the mouth end; and optionally wherein the light source is disposed at the distal end of the housing.
12. An electronic cigarette according to any preceding claim including an end cap (5) push fitted into the distal end of the housing.
13. An electronic cigarette according to any preceding claim wherein the housing comprises a first part containing the battery releaseably coupled to a second part containing the vaporiser.
14. An electronic cigarette according to any preceding claim wherein the porous matrix comprises inner and outer sheets of overlying fibrous material, with outer sheet having a greater pore size than the inner sheet for wicking the liquid to the inner sheet by capillary action.
15. An electronic cigarette according to any preceding claim including an atomisation aperture (32) in the tube configured to allow liquid to be drawn into the tube from the porous matrix so as to be atomised by passage through the aperture when the user draws on the mouth end.