This invention is directed towards duckbill valve arrangements and particularly those for use in beverage dispensing containers.
Duckbill valves are widely used one-way valves for controlling fluid flow in a variety of fluid systems. They typically comprise a pair of resilient lips extending from a cylindrical body and defining a valve opening. Fluid in between the lips provides an internal pressure to the valve and fluid on the outer surfaces of the lips provides an external pressure to the valve. When the external pressure is greater than the internal pressure the valve opening is sealed in a closed position. When the internal pressure is greater than a cracking pressure, being the internal pressure required to overcome the force exerted by the external pressure, fluid will be able to flow through the valve. As a result, duckbill valves are commonly used as check valves to prevent backflow and the like in fluid systems.
However, duckbill valves are not commonly used in beverage dispensing containers. The present invention is directed to duckbill valves suitable for use in beverage dispensing containers.
The present invention therefore provides a duckbill valve arrangement for a beverage dispensing container, the arrangement comprising: a tube comprising a resilient tube wall having an outer surface and defining an internal passageway; and a duckbill valve mounted within the passageway, the duckbill valve comprising a resiliently closable valve mouth arranged to be opened upon compression of the tube; wherein at least one groove extends along the outer surface of the tube wall for reducing the force required to compress the tube and open the duckbill valve.
The present invention further provides a duckbill valve arrangement for a beverage dispensing container, the arrangement comprising: a tube; first and second valve walls mounted to the tube and each having first and second ends, the first and second valve walls converging from their first ends to meet and form a resiliently closable mouth at their second ends, the mouth being openable upon compression of the tube; wherein the first and second valve walls increase in thickness from their first ends to their second ends.
The present invention yet further provides a beverage dispensing container comprising the aforementioned duckbill valve arrangements.
The present invention yet further provides a beverage dispensing container comprising: a beverage reservoir; a container outlet; and a duckbill valve positioned between the beverage reservoir and the container outlet for selectively enabling fluid communication therebetween, the duckbill valve comprising: first and second valve walls converging from first ends to second ends, the second ends being positioned closer to the reservoir than the first ends, and the second ends defining a valve mouth between valve tips.
By way of example only, embodiments of a duckbill valve arrangement are now described with reference to, and as show in, the accompanying drawings.
The present invention is generally directed towards a duckbill valve arrangement for a beverage dispensing container comprising a duckbill valve located within a tube. The tube has one or more grooves extending along its outer side. The duckbill valve may have thicker valve tips, indentations in the valve tips and/or supports attaching the valve tips to the tube.
An outer surface 15 of the tube 11 has a substantially oval cross-section with a centre point on the longitudinal axis 14. As a result, the cross-section of the tube wall 12 is shaped as an annulus having a substantially oval outer edge and a circular inner edge. Thus the tube wall 12 is thinnest where it meets a lateral axis 16 and increases in thickness from the lateral axis 16 towards a transverse axis 17. Such a shape is preferred as the outer oval shape enables the duckbill valve arrangement 10 to be mated correctly within a beverage dispensing container (see below) by matching a correspondingly shaped mounting means in the beverage dispensing container. When an actuator is aligned with the tube 11, the correct alignment of the actuator, i.e. directly over the duckbill valve (see below), can be seen. In addition, the thinner portions of the tube wall 12 enable a more compact arrangement of actuator and tube 11. However, the outer surface 15 of the tube 11 may be any other suitable cross-sectional shape, such as diamond, hexagonal, rectangular or non-rotationally symmetrical.
In this disclosure the lateral and transverse axes 16, 17 are orthogonal to each other in a first plane, the longitudinal and lateral axes 14, 16 are orthogonal to each other in a second plane and the longitudinal and transverse axes 14, 17 are orthogonal to each other in a third plane.
First and second grooves 20, 21 extend along the outer surface 15 of the tube 11 substantially parallel to the longitudinal axis 14. The first and second grooves 20, 21 are positioned to oppose one another in the transverse direction and thus are each located on the tube 11 where the tube wall 12 is at its thickest. The first and second grooves 20, 21 are V-shaped channels in the illustrated embodiments. The advantage of using a “V” shape is that a pivot point is created at the base of the “V” to aid in the compression of the tube 11. However, in other embodiments they may be another suitable shape, such as semi-circular, U-shaped or square shaped.
A duckbill valve is mounted within the passageway 13 to selectively enable fluid to flow therethrough.
First and second valve walls 32, 33 extend from the mounting wall 31 at first ends 34, 35 to second ends 36, 37. The first and second valve walls 32, 33 are separated at their first ends 34, 35 by an opening 38 formed in the mounting wall 31. The opening 38 is substantially in the shape of a rectangle with two opposing curved edges. As illustrated, the opening 38 is arranged such that there is a portion of the mounting wall 31 between the tube wall 12 and opening 38 (i.e. the tube wall 12 and opening 38 are separated). However, in other embodiments the curved edges of the opening 38 may be formed by the tube wall 12 itself.
The first and second valve walls 32, 33 converge towards each other from the opening 38 at their first ends 34, 35 and contact each other at their second ends 36, 37. Thus, when viewed in the third plane (i.e. longitudinal-transverse plane) as in
The outer edges of the first and second valve walls 32, 33, i.e. the edges in the transverse direction, are attached to the tube wall 12. Thus fluid can only pass through the valve mouth 41. The largest inner and outer surfaces 44, 45, 46, 47 of the first and second valve walls 32, 33, i.e. those which extend from the first ends 34, 35 to second ends 36, 37 between either side of the tube wall 12, are each substantially flat and planar. The thicknesses of the first and second valve walls 32, 33 are substantially constant or reduce from the first ends 34, 35 to the second ends 36, 37.
The tube 11 and duckbill valve 30 are formed from a resilient (i.e. elastomeric) material such that, after being squeezed or otherwise manipulated, it will return to the aforementioned shape in which the valve mouth 41 is closed. For example, if fluid of a relatively high pressure enters the tube 11 at the second end 25 it will open the valve mouth 41 provided that the fluid on the first end 24 of the tube 11 has a lower pressure. As soon as the pressure equalise at the first and second ends 24, 25 the valve mouth 41 will return to the closed position, although will not be sealed until the pressure at the first end 24 of the tube 11 is greater than the pressure at the second end 25 of the tube 11.
However, in the present invention the valve mouth 41 is openable by squeezing the outer surface 15 of the tube 11. In particular, if a compressive force is provided along the lateral direction (i.e. in the second plane, being the plane along which the valve mouth 41 extends when closed) the valve mouth 41 will open. This is a result of the elastic deformation of the first and second valve walls 32, 33 urging the valve tips 39, 40 away from each other to compensate for the reduced lateral dimension of the duckbill valve 30.
The magnitude of the compression force required to open the valve mouth 41 is substantially reduced by the presence of the first and second grooves 20, 21. If the first and second grooves 20, 21 were not present then, when the tube 11 is compresses, more tension would need to be applied to the tube wall 12 at its thickest points. Thus a relatively smaller compressive force is required due to the first and second grooves 20, 21.
Suitable resilient materials include elastomeric polymers, rubbers, butyl rubber, silicone and thermoplastic elastomers. The material is selected to have a low permeability to oxygen and low degradation to ensure that an effective seal is maintained when the valve mouth 41 is closed.
The duckbill valve arrangement 10 is preferably formed as a single piece by moulding or the like. Preferably the valve mouth 41 is not formed during the moulding and is instead formed afterwards, for example by cutting. Alternatively, the material at the valve mouth 41 may be formed very thin and is subsequently split to form the valve mouth 41 by the application of pressurised fluid. Alternatively, for example, the duckbill valve 30 and tube 11 may be formed separately and subsequently attached to one another.
A second embodiment of the duckbill valve 30 is illustrated in
The benefit of the thicker valve tips 39, 40 is that buckling thereof can be avoided when the compressive force is applied to the tube 11. It was surprisingly found that in the first embodiment both valve tips 39, 40 could curve the same way upon compression such that the valve mouth 41 did not open. By preventing buckling, the valve tips 39, 40 will curve away from one another and thus ensure that the valve mouth 41 opens upon compression of the tube 11.
A third embodiment of the duckbill valve 30 of the present invention is illustrated in
The indentations 50, 51 reduce the force required to open the valve mouth 41 upon compression.
A fourth embodiment of the duckbill valve 30 of the present invention is illustrated in
The advantage of the supports 60, 61, 62, 63 is that they prevent the valve tips 39, 40 from curving towards each another when the tube 11 is compressed. This ensures that the valve mouth 41 opens upon compression of the tube 11.
A fifth embodiment of the duckbill valve arrangement 10 is illustrated in
A sixth embodiment of the duckbill valve arrangement 10 is illustrated in
The duckbill valve arrangement 10 having any one of the embodiments of the duckbill valve 30 is particularly suitable for beverage dispensing containers. In particular, the duckbill valve arrangement 10 is suitable where the beverage dispensing container cannot be compressed to eject the fluid.
As illustrated in
A beverage dispensing arrangement 74 is arranged to compress the liquid against the valve tips 39, 40 of the duckbill valve 30. The beverage dispensing arrangement 74 may comprise a force application means, such as piston and springs, for applying a force (indicated by the arrows in
One or more actuators 75 are provided to supply a compressive force to the tube 11 when beverage is to be dispensed. When the compressive force is applied, the valve mouth 41 opens and fluid flows from the reservoir 71 by virtue of the force from the beverage dispensing arrangement 74. In order to provide the compressive force, the actuator(s) 75 are preferably positioned directly in line with the valve tips 39, 40 and valve mouth 41, such that the compressive force is applied substantially along the slit of the valve mouth 41. This ensures that buckling of the valve tips 39, 40 is avoided.
The first to fourth embodiments have been described with the inclusion of the first and second grooves 20, 21. However, it can be appreciated that the invention may instead comprise a tube without first and second grooves 20, 21 and may be directed instead to the thicker valve tips 39, 40, the indentations 50, 51 and/or the supports 60, 61, 62, 63.
The duckbill valve arrangement 10 is preferably arranged to allow a maximum flow rate of 12 ml/s, but may also be in the range of from 5 ml/s up to 30 ml/s or 50 ml/s. To achieve such flow rates the diameter of the passageway 13 is preferably around 11 mm, but other diameters are suitable, for example in a range of 2 mm to 25 mm. With such dimensions and with a silicone tube it has been found that a suitable compressive force for opening the valve mouth 41 is around 1 to 2 N.
Number | Date | Country | Kind |
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1411147.0 | Jun 2014 | GB | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2015/064071 | 6/23/2015 | WO | 00 |