EP1378485A1

EP1378485A1 - Container closure with tap and floating vent

Info

Publication number: EP1378485A1
Application number: EP02077658A
Authority: EP
Inventors: Tommi Raalind; Martin Schack Staffeldt
Original assignee: Schack Industriemballage ApS
Current assignee: Schack Industriemballage ApS
Priority date: 2002-07-05
Filing date: 2002-07-05
Publication date: 2004-01-07

Abstract

A closure is disclosed for mounting on a liquid container (25) and comprising a tap valve (23) and air reflux means (5, 14, 7, 27, 28, 31, 32, 33, 34, 35, 36) to allow vent air to enter the container as the liquid (26) exits.

An improved venting is provided by the closure, as at least a part of the vent air conduct (7, 27, 28, 33, 34, 35) is made from a flexible tube (27, 34) and buoyancy means (29) are provided near the distal, open end (31, 36) of the conduct extending in the interior of the container from the vent opening in the closure, so that the open end will be near below, at or above the free surface (30) of the liquid (26) inside the container (25). Hereby, the pressure of the vertical liquid column between the opening of the conduct and the free surface is reduced or eliminated and the reflux air may flow more freely and an improved venting is provided.

Description

The present invention relates to a closure for mounting on a liquid container and comprising a tap valve and air reflux means to allow vent air to enter the container as the liquid exits so as to avoid low pressure to build up within the container, resulting in an air lock and a possible collapse of the container.

BACKGROUND OF THE INVENTION

Dispenser tabs for liquid containers are advantageously combined with a vent opening for allowing reflux air to enter the container so as to avoid low pressure to build up within the container, resulting in an air lock and a possible collapse of the container. A vent opening may be provided as a second opening arranged at the opposite end of the container as the tap opening. Such a vent opening may however have the drawback that the plug for sealing the opening during transportation of the container is removed when the container is prepared for dispensing and there is a risk that the plug is lost when the container has been emptied and is to be sealed off and returned for refilling or destruction, which results in spillage of remaining liquid and possible contamination of the interior of the container with external contaminants entering through the non-sealed vent opening.
Closures integrating a dispenser tap and an opening for letting vent air into a container as liquid is drained from it are well known in the prior art. These tabs are primarily intended for use with single-opening containers that are not vented by a second opening arranged at the opposite end of the container as the tap opening.
A spigot tap is known from US 3,378,035, comprising a spigot with two openings, one for pouring out liquid and one for taking in reflux air, wherein the tap is opened by aligning both with the respective openings to the interior of the liquid container and open concurrently, so that reflux air is let into the container only while liquid is poured out. A rigid air tube extends into the container and upwards from the opening for reflux air, so as to provide an air exit above the level of the tap at running conditions.
A tap with a similar rigid air tube is disclosed in FR 2608722.
A beverage dispenser is disclosed in US 4,664,297, in which a dispensing valve can be coupled with the threaded necks of bottles. A rigid vent tube connected with the dispensing valve extends deeply into the beverage bottle to avoid an air lock impeding flow through the valve. The bottle is when the dispensing valve is in use, arranged in an upside-down inclined position, so that the vent tube extends upwards and into the air filled space at the bottom of the bottle opposite the neck portion of the bottle.
An improved venting of the liquid container, resulting in an increased dispensing rate, is advantageous to obtain and it is an object of the present invention to provide such improved venting.
The closure according to the present invention integrates a dispenser tap and an opening for letting vent air into a container as liquid is drained from it, and provides an improved venting, as at least a part of the vent air conduct is made from a flexible tube and buoyancy means are provided near the distal, open end of the conduct extending in the interior of the container from the vent opening in the closure, so that the open end will be near below, at or above the free surface of the liquid inside the container. Hereby, the pressure of the vertical liquid column between the opening of the conduct and the free surface is reduced or eliminated and the reflux air may flow more freely and an improved venting is provided.
The known integrated closures comprises rigid vent air conducts that are shaped and positioned so as to ensure that the opening at the distal end is situated within the liquid container at a position that is higher than the position of the liquid outlet. Thereby, it is made certain that a difference in pressure between the opening of the vent air conduct and the liquid outlet exists which counteracts an outflow through the vent air conduct. The length of the vent air conduct has to be limited for the integrated closure to be applicable to containers of various sizes and shapes.
By providing a flexible vent air conduct combined with buoyancy means near the distal, open end of the conduct according to the invention, an integrated closure is obtained that provides improved venting of the container while being flexible with respect to size and shape of the container to which it may be applied. In fact, the venting may be improved to such a degree that the integrated closure according to the present invention may render the use of a second vent opening in the container redundant. The closure according to the invention may also be used in combination with such second vent opening to improve the venting rate of the container.

DESCRIPTION OF THE INVENTION

Thus, the present invention relates to a closure suitable for mounting on a mouth situated on the lower part of a liquid container, the closure comprising
tap valve means for controlling the flow of liquid out of the liquid container, and
air reflux means for admitting vent air into the liquid container, the air reflux means comprising a vent air conduct for extending into the liquid container from a vent opening in the closure connecting to the exterior,
wherein
the vent air conduct comprises an elongated, flexible tube and is at a distal, open end provided with buoyancy means so as to bias the open end towards the free surface of the liquid in the container.
The tap valve means may be a spigot tap, e.g. as the one disclosed in US 3,378,035, a ball valve, a globe valve or any other type of valve that is suitable for the intended use, e.g. with respect to flow rate, requested adjustment features, durability and price.
The air reflux means comprises one or more vent openings in the closure, either in the mounting cap part of the closure, through the tap valve or both. Each vent opening is connected to the vent air conduct that may comprise one or more elongated, flexible tubes as described, each provided with buoyancy means. In a preferred embodiment, each vent opening is connected to a separate flexible tube.
The buoyancy means is means that in the relevant liquid will create sufficient buoyancy to lift the flexible tube or tubes upwards towards the free surface. The open end may not actually reach the free surface if the distance between the mouth of the liquid container and the free surface of the liquid exceeds the length of the tube; the venting of the liquid container is still improved substantially. However, it is preferred that the open end reaches the free surface. It is also preferred that the buoyancy means is arranged such that the open end of the vent air conduct extends from and opens above said free surface, so that the liquid will not enter the tube opening. It is under most conditions sufficient that the tube end extends 5 to 10 millimetres upwards from the free surface of the liquid, but under operational conditions where the container moves, e.g. on board a ship, it is preferred that the tube extends up to 25 to 30 millimetres from the free surface.
The buoyancy means may be made from natural materials, such as cork, wood or sponge, or from man made materials, such as foam made from polyurethane, polyethylene, polypropylene, etc. In embodiments of the present invention employing more than one flexible tube, a common buoyancy means is preferably used for all tubes.
The free surface of the liquid is defined as the upper, horizontal surface between the liquid and the air, as opposed to the surfaces bonded by container walls.
The tubes connected with the vent openings are flexible as opposed to the rigid tubes used in the prior art to ensure that the tube opening was above the level of the liquid discharge opening in the tap. The flexibility of the present tubes together with the buoyancy created by the buoyancy means has the effect that the open, distal end of the vent air conduct is biased towards the free surface of the liquid, i.e. that the open end is actually moved towards the free surface when the closure is mounted onto the liquid container. The required degree of flexibility is thus determined by the effect of the buoyancy means, so that the desired outcome is achieved. The flexible tube constitutes in preferred embodiments only a part of the vent air conduct, as the conduct leading from the vent opening and inside the container is constituted by a rigid tube, and the tubing through the buoyancy means is also preferably constituted by a rigid tube. The flexible tube may be made from any suitable material, such as natural or synthetic rubber, and the inner diameter of the tube is preferably in the range of 2-10 mm for most application, more preferred within the range of 4-6 mm, but inner diameters deviating from these ranges may also be applied in accordance with the invention.
The buoyancy effect of the buoyancy means it influenced by the density of the liquid within the container, i.e. whether it is a light liquid containing e.g. alcohol, oil or gasoline, a medium density liquid with a density around that of water, or whether it is a heavy liquid containing high density components, e.g. as suspended particles in a liquid. However, the buoyancy means may be selected for a specific liquid, or the closure may be formed with all-round buoyancy means suitable for a wide range of liquid densities.
It has proven to be an advantage that the buoyancy means is formed with a distance between its centre of gravity and its centre of buoyancy, so as to ensure a given spatial orientation of the open end of the vent air conduct relative to the buoyancy means. The spatial orientation may be that the opening is at the uppermost possible position, which may be advantageous when the opening is below the free surface as well as when the opening is at or above the free surface, or another specific orientation for openings above the free surface may be preferred in order to prevent liquid from entering the openings.
The distance between the centre of gravity and the centre of buoyancy may be obtained by having a non-uniform density distribution of the buoyancy means. This may e.g. be of the form of a gradually changing density of the material the buoyancy means is formed from, or it may be obtained by including a member of a deviant density, preferably a high-density member such as a lump of metal, e.g. lead, in the buoyancy means displaced from the buoyancy centre thereof. The deviant density member may alternatively be a section of a lower-density material, e.g. an air-filled cavity, or the buoyancy means may comprise a plurality of high-density and/or lower-density members, the terms high-density and lower-density refer to the density relative to the average density of the material of the buoyancy means.
The risk of spillage of liquid through the vent opening or openings is highest during the operation of mounting the closure on the container and during transportation of the container with the closure mounted thereon. As one solution to this problem, the vent opening or openings may be provided with a plug or plugs that may be inserted when there is a risk of spillage through the vent opening or openings. The air reflux means may comprise one or more non-return valves arranged in some of or all of the tubes constituting the vent air conduct for preventing liquid from flowing out of the one or more vent openings.
As another alternative that may be used alone or in a combination with the non-return valve or valves and/or the plug or plugs, a vent valve means may be operational connected to the tap valve means to control the passage between at least one vent opening and the open end of the corresponding vent air conduct concurrently with the control of the flow of liquid out of the liquid container. An examples hereof is given below and may also be found in the prior art, e.g. in US 3,378,035.
The closure comprises preferably connecting means for providing a releasable, sealed connection between the closure and a liquid container, such as a releasable snap-in socket. However, it is preferred the connecting means comprises an externally or internally threaded part on the closure means for engaging with a corresponding threaded part on the liquid container. The connecting means may comprise a mounting cap as discussed in the examples below.
The present invention further relates to a liquid container having a closure according to the above described mounted on a mouth at a lower part thereof.

BRIEF DESCRIPTION OF THE FIGURES

The present invention is further explained by means of the examples of embodiments shown in the enclosed drawing, of which Figs. 1-4 show a prior art tap known from US 3,378,035,
Fig. 1 is an exploded elevation of a spigot tap, part being shown in cross-section,
Fig. 2 is a section taken along II-II of Fig. 1,
Fig. 3 is a cross-section taken along III-III of Fig. 1,
Fig. 4 is a cross-section taken along IV-IV of Fig. 1,
Fig. 5 is a cross-section of a first embodiment of the closure of the present invention mounted on a liquid container,
Fig. 6 is a cross-section of a second embodiment of the closure of the present invention mounted on a liquid container, and
Fig. 7 is a mounting cap for the closure according to the second embodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

The tap shown in Figs. 1-4 is a prior art tap that may be employed in a closure according to the present invention. However, other types of taps may as discussed previously be employed as well.
The tap shown in the drawing consists of a spigot part 1 rotatable in fluid-tight engagement within a sleeve part 2. The sleeve part 2 has integral therewith a tubular gland 3, whose axis is perpendicular to the rotational axis of the spigot part and which is formed to engage within the mouth or other delivery opening of the liquid container. Obviously the form of the gland 3 depends upon the kind of opening with which it is to be engaged and the form shown in the drawing is shown by way of example only. A mounting cap may be provided to mount the tap on a specific kind of container opening.
Communication between the gland 3 and the sleeve part 2 is provided by a large liquid part 4. An integral tubular projection 6 within the gland communicates with the sleeve part by an air port 5 and has secured thereto a separately formed air tube 7 shaped to enter the container and provide an air exit at 8 above the level of the tap under running conditions.
The spigot part consists of a tubular moulding open at its lower end 9 and having a handle 10 at its closed upper end. Adjacent to the upper end the spigot part is formed externally with circumferential ridge of enlarged diameter between a pair of grooves, which ridge and grooves co-operate with complementary formations 12 within the liner to locate the spigot part axially.
Formed in the wall of the spigot are a liquid entrance port 13 shaped and positioned to correspond with the port 4 and an air exit port 14 positioned to correspond with the small air port 5.
Internally the spigot part is divided by a septum 15 having a tight sliding fit within a pair of longitudinal grooves 16 and 17. The lower end of the spigot part is cut through at the bases of the grooves to provide short slots for the reception of transversely projecting lugs 18 and 19 provided at the lower en of the septum 15. The slot for the reception of lug 19 is shown at 20 in Fig. 3.
At its upper end the septum 15 has a segmental part 21, the curved edge of which is a close mating fit at 21' with the inner surface of the spigot between the ports 13 and 14.
By the septum 15, the spigot part is divided to provide a liquid delivery passageway leading from the entrance port 13 to a liquid exit at the open end of the spigot part and an air reflux passageway, of smaller cross-sectional area than the liquid delivery passageway, leading from the open end of the spigot part to the exit port 14. The open end of the spigot part is of course divided to form the liquid exit and air entrance by the lower edge of the septum.
With the spigot 1 rotated to position the ports 13 and 14 out of communication with the ports 4 and 5, the tap provides a satisfactory seal for the container. On turning the spigot within the sleeve part, the exit port 14 is placed in communication with air port 5 and entrance port 13 with the liquid port 4. The circumferential displacement of the edge 21A of the exit port 14 beyond the edge 22 of the entrance port 13, by an amount equal to the circumferential displacement between the corresponding edges of the port 4 and 5, ensures that the air and liquid passageways begin to communicate with the container at the same moment. When the liquid is being delivered, air passes into the container via end 8 of the tube, or from the end of tubular projection 6 if tube 7 is omitted.
In Fig. 5, a first embodiment of the present invention is disclosed, in which the tap 23 as discussed above and shown in Figs. 1-4 is mounted by means of a mounting cap 24 (only indicated) on the mouth of a container 25 containing a liquid 26. The use of the known tap 23 is made for illustrative purposes and other kinds and types of taps could be employed, either integrating or not integrating a vent opening 5 that is closed by a valve 1.
A flexible tube 27 is at one end connected to the air tube 7 of the tap 23 and at the other end connected to a rigid tube 28 passing through a float 29 made from polyurethane foam. The float 29 has outer dimensions that allow it to pass the standard openings of containers 25. The length of the flexible tube 27 and dimensions of the container 25 allow the float 29 to reach the free surface 30 of the liquid 26. However, it is also within the scope of the present invention to provide embodiments in which the float does not reach the surface 30 but only bias the outlet of the open end 31 of the vent air conduct 14, 5, 7, 8, 27, 28 towards the free surface 30 of the liquid 26.
A second embodiment of the present invention is shown in Fig. 6, in which a further vent opening 32 is provided in the mounting cap 24 and a further rigid air tube 33 extends from the vent opening 32 and into the container 25. A second flexible tube 34 is at one end connected to the air tube 33 and at the other end to a rigid tube 35 passing through the float 29 that also provides buoyancy for the first flexible tube 27, and the rigid tube 35 is open 36 towards the air filled space 37 at the top of the container 25. The parts referred to as 32, 33, 34, 35 and 36 thereby establish a second path of the vent air conduct.
Two separate floats could has been provided as well, and the use of rigid tubes 7, 28, 33, 35 at the two ends of the flexible tubes 27, 34 may be omitted and the flexible tubes 27, 34 may extend all the way from the vent openings 5, 32 to the open ends 31, 36 of the vent air conduct. More corresponding vent openings and thereto communicating open ends may also be added if further venting of the container is required.
Fig. 7 shows a mounting cap 24 for use with the second embodiment shown in Fig. 6. The mounting cap 24 is above seen from the outside of the container 25 and below seen in a cross-section. The cap 24 has a central opening 38 for receiving the gland 3 of the tap and holding the gland 3 in a tight and sealing connection. The mounting cap 24 is at the outer periphery 39 provided with indentations 40 to enhance the user's grip of the mounting cap during the mounting and dismounting operation. One vent opening 32 is provided in the middle section 41 of the cap 24 between the central opening 38 and the periphery 39, but more similar vent openings may be provided.
The mounting cap 24 is provided with an internal thread 42 for cooperating with a corresponding external thread of the mouth of the container 25, but other means of releasable, sealed connections between the cap 24 and the container 25 may be provided.
The mounting cap 24 may be provided with various types of connection means and diameters to mount the tap on various types of container mouths. However, the mounting cap is not a required or essential part of the present invention, and the closure may be integrated in the tap valve or the tap valve a shown in the first example may be mounted directly to a container having a suitable mouth.

Claims

A closure suitable for mounting on a mouth situated on the lower part of a liquid container (25), the closure comprising
tap valve means (23) for controlling the flow of liquid (26) out of the liquid container (25), and
air reflux means (5, 14, 7, 27, 28, 31, 32, 33, 34, 35, 36) for admitting vent air into the liquid container (25), the air reflux means comprising a vent air conduct (7, 27, 28, 33, 34, 35) for extending into the liquid container (25) from a vent opening (5, 32) in the closure connecting to the exterior,
characterised in that
the vent air conduct comprises an elongated, flexible tube (27, 34) and is at a distal, open end (31, 36) provided with buoyancy means (29) so as to bias the open end (31, 36) towards the free surface (30) of the liquid (26) in the container (25).
A closure according to claim 1, wherein the buoyancy means (29) is arranged such that the open end (31, 36) of the vent air conduct opens above said free surface (30).
A closure according to claim 1 or 2, wherein the buoyancy means (29) is formed with a distance between its centre of gravity and its centre of buoyancy, so as to ensure a given spatial orientation of the open end (31, 36) of the vent air conduct relative to the buoyancy means (29).
A closure according to claim 3, wherein said distance is obtained by including a member of deviant density in the buoyancy means (29), displaced from the buoyancy centre thereof.
A closure according to any of claims 1 to 4, wherein the air reflux means comprises a non-return valve for preventing liquid from flowing out of the vent opening (5, 32).
A closure according to any of claims 1 to 5, wherein the air reflux means comprises a plurality of vent openings (5, 32) in the closure and the vent air conduct comprises a corresponding number of elongated, flexible tubes (27, 34) provided with buoyancy means (29).
A closure according to any of claims 1 to 6, wherein a vent valve means operational connected to the tap valve means (23) controls the passage between at least one vent opening (5) and the open end (31) of the corresponding vent air conduct concurrently with the control of the flow of liquid out of the liquid container (25).
A closure according to any of the preceding claims, further comprising connecting means for providing a releasable, sealed connection between the closure and a liquid container.
A closure according to claim 8, wherein the connecting means comprises a threaded part (42) on the closure means for engaging with a corresponding threaded part on the liquid container (25).
A liquid container (25) having a closure according to any of claims 1-9 mounted on a mouth at a lower part thereof.