Liquid dispensing apparatus

Abstract

A liquid metering dispensing apparatus has a housing (1) within which is a capillary channel 30 for the liquid. A loading mechanism 5 is arranged to present a container 6 holding a metered dose of the

Description

This invention relates to a liquid dispensing apparatus and in particular, although not exclusively, for use as an inhaler or vaping device. With a medicinal inhaler, it is required to dispense a precise quantity of a liquid. It is known from US-A-7222755 to provide a liquid metered dispensing squeezable bottle containing a dip tube and a one-way valve system at the bottom of the dip tube. The dip tube includes a leg that is flexible to permit folding of the leg toward the container for insertion into a standard neck or narrow neck container. US-A-7040513 discloses a valve body and a valve member which is slidably mounted within the body between rest and dispensing positions. The valve has a metering chamber to contain a metered quantity of liquid each time the valve is activated, the valve being formed by a diagonal hole with the valve member. The present invention seeks to provide an apparatus in which a pre-metered single dose is taken from a liquid reservoir and to prevent the reservoir from exposure to the heating process. According to this invention there is provided a liquid dispensing apparatus including a housing containing a heating device within which is a capillary channel for said liquid, loading means arranged to present a container holding a pre- metered dose of said liquid to said capillary channel, said loading means including fracturing means arranged to fracture said container so that said pre-metered dose of liquid is able to enter said capillary channel, activation means arranged to detect said pre-metered dose into said capillary channel and energize said heating device to vaporize said pre-metered dose. Preferably, the loading means also includes support means for said container and is reciprocally mounted in said housing with respect to said capillary channel so that, in one position thereof, said container is loadable onto said support means and, in another position thereof, said support means is arranged to present said container to said capillary channel. Conveniently, the loading means is a manually operable button comprising first and second members which are movable with respect to one another interspaced by a resilient platform arranged to support said container, and biasing means arranged to urge said first and second members apart. Advantageously, the fracturing means of said loading means is arranged to rupture a frangible seal of said container to enable said pre-metered dose to enter said capillary channel. Preferably, said fracturing means is a leading end of said first member arranged, in operation, to apply pressure and burst said container frangible seal. Conveniently, the loading means is transversely mounted with respect to a longitudinal axis of said housing to be slidable in and out of said housing. Conveniently, the biassing means, such as a compression spring, is provided to bias said loading means radially outwardly from said housing. Advantageously, a sealing gasket is provided between the heating device and the resilient platform so that, in operation, when the container is located on the resilient platform and the resilient platform locates the container in situ with the capillary channel, so there is a seal between the container and the heating device, said gasket having an opening therein to permit liquid from the container to enter the capillary channel. Advantageously, latching means is provided to secure locking means in a position in the housing to load the container onto the resilient platform and to secure the loading means with the container in situ with the capillary channel. Conveniently, the heating device is made of an electrically-resistive material selected from electrically conductive ceramic materials, doped ceramics, molybdenum disilicide, carbon, graphite, metal, quartz or composite materials made of a ceramic material and a metallic material or a cermet peripherally surrounding the heating device. Advantageously, when the heating device is metallic, preferably, it is coated with a capacitive coating to prevent the heating element material thereof from heating during inhalation without liquid on the heating element. Preferably, the activation means includes liquid detecting means to determine whether the capillary channel contains liquid and consequently activate an electrical heating element of said heating device. Conveniently, the detecting means is a cermet wick sensor. Advantageously, a visible and / or audible and / or haptic signal is provided to a user to signify when liquid is present in the heating device and the heating element is activated by inhalation of a user. In alternative embodiments, the heating device is activated by a manual control, e.g., a button, or by a pressure transducer when a user sucks on a mouthpiece attached to the container, to vaporize the liquid. Conveniently, the heating device includes an energy source arranged to heat an electrical element. Advantageously, the heating device is made of an electrically resistive material such as doped ceramics, molybdenum disilicide carbon, graphite, metal, quartz or composite materials made of a ceramic material and a metallic material. Conveniently, the heating device is an infrared heating element, a photonic source or an inductive heating element. Advantageously, the heating device is arranged to convert the metered dose into droplets of 2 - 5microns, or less than 2 microns for systematic absorption. Preferably, the heating device has a temperature in the range 20°C - 200°C, usually in the range 30°C - 90°C, and, preferably, 60°C. Conveniently, the liquid is a medicament, or nicotine, plus an excipient including propylene glycol, vegetable glycerine, or an organic solvent such as ethanol. Advantageously, the heating device is made from a capacitive material, to detect the presence of liquid on the heating element and provide a stimulus to the user in the form of an audible, visual, or haptic stimulus. The invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figures 1-7 show schematic cross-sectional views of a liquid dispensing apparatus in accordance with this invention in differing operational positions, Figure 8a shows a partial side view of the liquid dispensing apparatus latching arrangement in a reset position, Figure 8b shows a cross-sectional along double arrow-headed lines A-A of Figure 8a, Figure 9a shows a partial side view of the liquid metering dispensing apparatus in a locked position for locating the container in situ with the capillary channel, and Figure 9b is a cross-sectional view along double arrow-headed lines B-B of Figure 9 a. In the Figures like reference numerals denote like parts. The liquid metering dispensing apparatus, shown in Figures 1-7, has a housing 1 providing an upper chamber 2 which is a vapor chamber and a lower chamber 3 within which is a heating device 4 and a loading mechanism 5 for a container 6 within which is a single dose of metered liquid, the loading mechanism having a longitudinal axis that is transverse to the longitudinal axis of the housing. A dividing wall 7, within which is an aperture 8, is located in the housing between the upper and lower chambers, the wall supporting the heating device 4 in the lower chamber 3. At an upper end of the housing is a mouthpiece 9 having an internal channel 10. The loading mechanism 5 is formed by a first member 20 and a second member 21, the loading mechanism 5 being transversely mounted with respect to the longitudinal axis of the housing and is arranged to be slidable in and out of the housing. Interposed between the first and second members is a resilient platform 22 for supporting the container 6 and a leading end of the first member has a beveled face 23 for fracturing a frangible seal of the container 6. A removable lid 24 is provided over the container and the lid may be hinged or slidable to permit loading and extraction of the container. The lid has a hole therein to permit egress of liquid from the container into the heating device 4. The first member has an axial hole 25 that is closed at one end to locate a compression spring 26, the compression spring passing through an axial hole 27 in the second member 21 and abutting an internal wall of the lower chamber 3. Located between the heating device 4 and the lid 24 is an apertured gasket 28 arranged in operation to provide a seal between the heating device and the lid 24. A further apertured gasket 29 is provided between the dividing wall 7 and the heating device 4. The heating device 4 has a capillary channel 30 therein for receiving liquid from the container 6. The heating device has a heating element 31. The heating element may comprise a single heating element or a plurality arranged suitably to effectively heat and vaporize the liquid. The heating element may be made of an electrically-resistive material selected from electrically conductive ceramic materials, doped ceramics, molybdenum disilicide, carbon, graphite, metal, quartz or composite materials made of a ceramic material and a metallic material or a cermet peripherally surrounding the heating device. Alternatively, the heating element could be an infrared heating element, a photonic source or an inductive heating element, when the heating element is metallic, preferably, it is coated with a capacitive coating to prevent the heating element material from heating during inhalation without liquid on the heating element. Further, an anti-oxidation coating, such as Apticote 810, may be applied to the heating element surface to prevent harmful toxins forming. Where the heating element is made of ceramic, it is controlled by patient inhalation and when all the liquid has been vaporized the elements may continue to heat until a safety thermal threshold shuts off the power supply. A benefit of using a ceramic mesh compared to a metal element is that if the element is heated without liquid being present, it will not produce toxins from oxidation, although this problem may be overcome if a metal mesh is coated with plastic material. An alternative heating element is that of a doped ceramic which is, again, heated upon inhalation, but which shuts off the power supply in dependence upon feedback from a capacitive signal read out from the doped material. The heating element is arranged to convert the metered dose into droplets of 2 - 5 microns or less than 2 microns for systematic absorption. The heating element may produce heat in the range 20°C - 200°C, usually in the range 30°C - 90°C, and, in a preferred embodiment, 60°C, but the temperature is drugdependent. The vapor temperature during activation may be in the range 40°C - 60°C. The liquid in the container may be a medicament for administration to a user. The medicament, or nicotine, may be plus an excipient including propylene glycol, vegetable glycerin, or an organic solvent such as ethanol. The excipients may be [100 / 0PG / VG or VG / PG] to [50 / 50PG / VG| and include up to 30% ethanol. As shown in Figures 8a and 9a, the side wall of a lower part of the lower chamber 3 has a pair of rectangularly-shaped apertures 40, 41 in opposing side walls for cooperative engagement with resiliently flexible fingers 42 on the second member 21. In the position shown in Figures 8a and 8b, the loading mechanism is locked by the fingers 42 engaging apertures 40 so as to receive or remove the container 6. In the position shown in Figures 9a and 9b, the loading mechanism is compressing compression spring 26 and the fingers 42 are held in position in the apertures 41. In operation, as shown in Figure 1, the loading mechanism is locked by the fingers 42 being held in the apertures 40 against the force of the compression spring 26, and the lid 24 is opened to insert the liquid container 6 which is, preferably, a blister having a frangible seal. By virtue of the fingers 42 having beveled forward faces, so when pressure is exerted in the direction of arrow-headed line 43 to compress the compression spring 26, so the fingers move out of engagement with apertures 40. As the loading mechanism, which is in the form of a manually operable button, is depressed, as shown in Figure 2, and in the direction of arrow headed line 43 in Figures 8a and 8b, so the compression spring 26 is starting to be compressed and the container 6 is transferred under the capillary channel 30. As shown in Figure 3, the second member 21 of the loading mechanism contacts an inner wall of the lower chamber 3 and, with further pressure on the loading mechanism, so the spring is further compressed and the beveled face 23 of the first member 20 fractures the frangible seal of the container 6 which creates a liquid droplet between the lid 24 and the capillary channel 30, the gasket 28 forming a liquid seal with the lid 24 (as shown in Figure 3). When the loading mechanism is fully depressed, as shown in Figure 4, the fingers 42 engage with the aperture 41 to lock the loading mechanism in position and the adjacent end surfaces of the first and second members abut one another. With movement of the first member over the entrance of the capillary channel 30, so a droplet is fully formed and the container is sealed against the gasket 28. As shown in Figure 5, the liquid dose is drawn by capillary action upwardly in the capillary channel 30 and once the channel is filled the heating element is activated by a manual control, e.g., a button, or by a pressure transducer when a user sucks on the mouthpiece 9, to vaporize the liquid as shown in Figure 6. Alternatively, the heating element is made from a capacitive material, to detect the presence of liquid on the heating element and provide a stimulus to the user in the form of but not limited to an audible, visual, or haptic stimulus. This stimulus could aid as an indicator to begin inhalation. After the liquid dose has been taken, to release the mechanism from the position shown in Figures 4-6 and 9a and 9b, the fingers are pressed inwardly, as shown by arrow-headed lines 44, to release the loading mechanism from being locked to the lower chamber 3, and the compression spring 26 pushes the loading mechanism to the initial position where the fingers 42 engage with apertures 40. The lid is opened and the spent container is removed. To release the mechanism from the position shown in Figures 4-6 and 9a and 9b, the bosses are pressed inwardly, as shown by arrow-headed lines 44, to release the loading mechanism from being locked to the lower chamber 3. The capillary channel and heating element are designed according to the formulation properties, and particle distribution required. The housing 1 and loading mechanism 5 may be made of plastics / polymer, metal or metal alloy. The gaskets may be made of plastic / polymer or rubber. 5 In this specification, an apparatus / method / product "comprising" certain features is intended to be interpreted as meaning that it includes those features, but that it does not exclude the presence of other features. Many variations are possible without departing from the scope of the present invention as defined in the appended claims.

Claims

1. A liquid metering dispensing apparatus including a housing (1) containing a heating device (4) within which is a capillary channel for said liquid, loading means (5)5 arranged to present a container (6) holding a metered dose of said liquid to said capillary channel (30), said loading means (5) including fracturing means (23) arranged to fracture said container so that said material dose of liquid is able to enter said capillary channel, activation means (9) arranged to detect said metered dose into said capillary channel and energize said heating device to vaporize said metered dose, wherein the loading means10 (5) is transversely mounted with respect to a longitudinal axis of said housing (1) to beslidable in and out of said housing.

2. An apparatus as claimed in claim 1, wherein the loading means (5) also includes support means (22) for said container (6) and is reciprocally mounted in said housing15 with respect to said capillary channel (30) so that, in one position thereof, said container is loadable onto said support means and, in another position thereof, said support means is arranged to present said container to said capillary channel.

3. An apparatus as claimed in claim 1 or 2, wherein the loading means (5) is a20 manually operable button comprising first and second members (20, 21) which are movable with respect to one another interspaced by a resilient platform (22) arranged to30 08 24support said container, and biasing means (26) arranged to urge said first and second members apart.

4. An apparatus as claimed in any preceding claim, wherein the fracturing means5 (23) of said loading means is arranged to rupture a frangible seal of said container (6) toenable said metered dose to enter said capillary channel.

5. An apparatus as claimed in claim 4, wherein said fracturing means is a leading end (23) of said first member (20) arranged, in operation, to apply pressure and burst said10 container frangible seal.

6. An apparatus as claimed in claim 3, wherein, the biassing means (26), such as a compression spring, is provided to bias said loading means radially outwardly from said housing.

157. An apparatus as claimed in claim 3 or 6, wherein a sealing gasket (28) is providedbetween the heating device (4) and the resilient platform (22) so that, in operation, when the container is located on the resilient platform and the resilient platform locates the container in situ with the capillary channel, so there is a seal between the container and20 the heating device, said gasket having an opening therein to permit liquid from the container to enter the capillary channel.30 08 248. An apparatus as claimed in claims 3. 6 or 7. wherein latching means (41, 42) is provided to secure locking means in a position in the housing (1) to load the container (6) onto the resilient platform (22) and to secure the loading means (5) with the container (6) in situ with the capillary channel (30).

59. An apparatus as claimed in any preceding claim, wherein the heating device (4) is made of an electrically-resistive material selected from electrically conductive ceramic materials, doped ceramics, molybdenum disilicide, carbon, graphite, metal, quartz or composite materials made of a ceramic material and a metallic material or a cermet10 peripherally surrounding the heating device.

10. An apparatus as claimed in claim 9, wherein when the heating device (4) is metallic, it is coated with a capacitive coating to prevent the heating element material thereof from heating during inhalation without liquid on the heating element.1511. An apparatus as claimed in any preceding claim, wherein the activation means includes liquid detecting means to determine whether the capillary channel contains a sufficient volume of liquid and consequently activate an electrical heating element (31) of said heating device.2012. An apparatus as claimed in claim 11, wherein the detecting means is a cermet wick sensor.30 08 2413. An apparatus as claimed in claim 11, wherein a visible and / or audible and / or haptic signal is provided to a user to signify when liquid is present in the heating device and the heating element is activated by inhalation of a user.5 14. An apparatus as claimed in any preceding claim, wherein the heating device (4) isactivated by a manual control, e.g., a button, or by a pressure transducer when a user sucks on a mouthpiece (9) attached to the container, to vaporize the liquid.

15. An apparatus as claimed in any preceding claim, wherein the heating device (4) 10 includes an energy source arranged to heat an electrical element.

16. An apparatus as claimed in any preceding claim, wherein the heating device (4) is made of an electrically resistive material such as doped ceramics, molybdenum disilicide carbon, graphite, metal, quartz or composite materials made of a ceramic material and a 15 metallic material.

17. An apparatus as claimed in claim 1, wherein the heating device (4) is an infrared heating element, a photonic source or an inductive heating element.20 18. An apparatus as claimed in any preceding claim, wherein the heating device (4) isarranged to convert the metered dose into droplets of 2 - 5 microns, or less than 2 microns for systematic absorption.30 08 2419. An apparatus as claimed in any preceding claim, wherein the heating device (4) has a temperature in the range 20°C - 200°C, usually in the range 30°C - 90°C, and, preferably, 60°C.

520. An apparatus as claimed in any preceding claim, wherein the liquid is a medicament, or nicotine, plus an excipient including propylene glycol, vegetable glycerine, or an organic solvent such as ethanol.10 21. An apparatus as claimed in any preceding claim, wherein the heating device (4) ismade from a capacitive material, to detect the presence of liquid on the heating element and provide a stimulus to the user in the form of an audible, visual, or haptic stimulus.

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