WO2000020326A1

WO2000020326A1 - Closure valves

Info

Publication number: WO2000020326A1
Application number: PCT/GB1999/003293
Authority: WO
Inventors: Michel Boulange; John Denis Willingham
Original assignee: Royal Packaging Industries Van Leer N.V.
Priority date: 1998-10-06
Filing date: 1999-10-05
Publication date: 2000-04-13
Also published as: AU6112799A; GB9904389D0; GB0108637D0; GB2357496B; GB2357496A

Abstract

Disclosed herein is a valve closure assembly (10) for a fluid dispense system, wherein the closure valve (12) includes a body component (20) and a base component (44), the body component (20) and/or the base component (44) being formed from a resilient plastics material and having axial slots (56, 61) defining flexible panels (57, 62) in the body component and/or the base component, each panel having a detent (58) arranged to snap engage with a co-operating feature (34, 66) of the base component or the body component respectively; the base panels (57) may snap-fit into ports (34) in the body side wall.

Description

CLOSURE VALVES

This invention relates to closure valves for containers and it particularly, but not exclusively, relates to a low cost closure valve for a one-way positive gas-pressure fluid dispense system.

Positive gas-pressure fluid dispense systems, such as for dispensing beer and the like beverages, comprise:- a pressure vessel, such as a beer keg having a neck in the top thereof; a closure valve having a gas valve to control ingress of propellant gas into the keg and a fluid valve to control egress of beer, to fit the keg neck and having a spear to reach to the bottom of the keg; and, a coupling head having a gas valve to control propellant gas from a source thereof and a fluid flow passage and, on mating with the closure valve, being operative to open both of the gas valves and the fluid valve to permit beer to be dispensed from the keg, via the spear, the closure valve fluid valve and the coupling head.

One major problem with known positive gas-pressure fluid dispense systems is that they are designed for multiple usage and therefore have a high cost of the component parts and complex assembly thereof. Parts are screwed or welded together or worked, such as by forming or shaping, so as to, for example, trap valve components within valve bodies and are made from expensive long-lasting materials; typically stainless steel.

It is an object of the present invention to provide a closure valve for a fluid dispense system that is inherently inexpensive to manufacture and which is therefore suitable for single, so-called "one-way", or a limited number of cycles. By "cycle" is meant the steps of attaching a closure valve to a pressure vessel, cleaning and filling the vessel with beverage at a point of origin, transporting the filled vessel to a point of dispense, connecting the filled vessel to the coupling head, dispensing the beverage and, when the vessel is empty, either disposing of the vessel and closure valve or returning the vessel and closure valve to the point of origin for reuse. According to the present invention, a valve closure for a fluid dispense system, wherein the closure valve includes a body component and a base component and the base component and/or the base component has one or more parts shaped and configured to engage as a snap-fit features of the other component; the body component and/or the base component are formed from a resilient plastics material with flexible panels in the body component and/or the base component and each having a detent arranged to snap engage with a co-operating feature of the base component or the body component respectively. By this means, valve assembly can be much simplified in that the components can be fitted one to other and then simply pushed together with consequent savings to make the closure valve suitable for the aforesaid single or limited usage. Clearly, although intended for single or limited usage, the principal of the present invention can also be applied to multiple usage closure valves.

Whilst snap-fit engagement of valve closure components is known; see for example GB-A-21564447, GB-A-1577116, WO-A-9738936 and US-A-5477883, the problem with such prior assemblies is that plastics materials could not be used for the snap-fit components because the material would not retain sufficient resilience when subjected to brewery filling line sterilisation temperatures. The flexible panels of the present invention overcome this problem by effectively extending the upper temperature range of the plastics material from which the valve closure components are made.

According to an embodiment of the present invention and wherein the closure valve is a ring-type poppet valve having a body, a central stem component and a base; the base and/or the body is shaped and configured to snap to the body and/or the base respectively and the stem and/or the base is shaped and configured to snap to the base and/or the stem respectively; to trap and locate a valve member and spring within the valve body.

The above and further features of the present invention are illustrated, by way of example in the Drawings; wherein:-

Fig. 1 is a sectional elevation of a closure valve in accordance with the present invention, fitted into a beer keg; Fig. 2 is an enlarged sectional elevation of the closure valve of Fig. 1 , split to show the closed and open positions of the valve;

Fig. 3 is an exploded, part-sectional elevation of a valve body for the closure valve of Fig.1; and,

Fig. 4 is a detail view illustrating the safety action of the closure valve

The closure valve shown by the Drawings is a low cost, safety and snap-fit closure valve developed for single or limited usage with so-called "one-way" kegs.. These being beer kegs designed for single or a very few cycles of use; that is assembly, racking for cleaning and sterilisation, filling with beer at a point-of-origin, transportation to the point- of-sale, dispensation of beer and, when the contents are exhausted, disposal or return to the point-of-origin for cleaning and sterilisation and refilling with beer. To meet the criteria for such use the closure valve has to be cheap to manufacture and assemble whilst meeting all safety requirements.

A valve closure assembly 10, consisting of a closure valve 12 and a descending spear 14, is shown in Fig. 1 to be screwed into the neck 16 of a beer keg 18.

The closure valve 12 comprises a generally cylindrical body 20 formed of a filled acetal copolymer (POM), which is known for its ability to withstand 130°C temperatures, and having an external thread 22 extending most of the length of the valve body and to mate with the threaded keg neck 16. The top of the valve body 20 has a radially outwardly extending, integral flange 24 which has an inner circular rim 26 defining the outer peripheral valve seat of an annular valve port 28. A sealing ring 30 is trapped under the valve flange 26 and against the mouth of the keg neck 16. The shape of the outer rim 32 of the valve flange depends upon the coupling head to which the closure valve is to be coupled; in the example tri-lobal. The body has a series of four regularly spaced ports 34 in the threaded side wall.

A valve stem 35, also formed of POM, is fitted within the valve body 20, the stem has a cylindrical, central bore 36 closed at the top by a cap 38 that is coplanar with the valve flange 24. The outer, circular rim 40 of the cap defines the inner peripheral seat of annular valve port 30. A series of ports 42 are provided in the side walls of the stem bore 36.

A cylindrical, cup-shaped base 44, again formed of POM, is fitted within the open bottom of the valve body 20. The base has a cylindrical, central, axial, hollow, spigot 46; the top of which flares radially outwardly to form a frusto-conic valve seat 48. The valve stem 35 fits into the top of the base spigot and the spear 14 is a push-fit into the bottom of the base spigot 46.

A poppet-ring valve member 50, formed of EPDM (a copolymer of Ethylene-

Propylene-Diene-Monomers) or nitrile rubber, is located about the valve stem 35 under the stem cap 38 and is loaded there against by a stainless steel coil spring 52 that encircles the stem and is trapped between the valve base 44 and a POM support 54 for the valve member 48. The poppet valve member 50 normally closes the annular valve port 28, sealing against the outer valve seat 26 and the inner valve seat 40 (as shown to the left in Fig. 2). The closure valve 12 is opened by a co-operating member of a coupling head (not shown) that seals against and pushes the poppet valve member 50 down the valve stem 35 until its lower inner periphery seals against the valve stem valve seat 48 (as shown to the right in Fig. 2); forming a path for ingress of propellant gas that is sealed from and co- axially extends about a central path for egress of dispensed beer.

The side wall of the valve base 44 has a series of eight axial slots 56 to define four axially extending panels 57, each panel incorporates a radially outwardly extending detent 58. The valve base material is resilient so that, on assembly, as the base is fitted into the valve body, the panels can deflect inwardly until the detents reach the valve body ports 34 and can return outwardly so that the detents 58 can lock into the valve body ports; the valve base is a snap-fit in the valve body. The valve base 44 has an interrupted peripheral, radial flange 60 to abut the bottom of the valve body 20 to limit incursion of the valve base into the valve body.

The side wall of the valve stem 35 has a series of eight axial slots 61 to define four axially extending panels 62, each panel incorporating a radially outwardly extending detent 64. The valve stem material is resilient so that, on assembly, as the stem 35 is fitted into the valve base spigot 46, the panels can deflect inwardly until the detents 64 reach and lock over a radially inwardly directed shoulder 66, formed by an enlarged bore diameter inside the spigot; the valve stem is a snap-fit in the valve base. The valve stem 35 has, beneath the ports 42, a radially outwardly directed shoulder 68, formed by a reduced stem diameter, against which the top of the valve base spigot abuts to limit incursion of the valve stem into the valve base spigot.

The use of slots 56 and 62 to form panels 57 and 62, incorporating detents 58 and 64, enables the panels to be sufficiently resilient to enable the detents to snap into the ports 34 or under the shoulder 66 whilst remaining sufficiently rigid to resist disengagement during usage; particularly when subjected to the sterilisation temperature (140°C) of a brewery filling line, a temperature that is higher than the normal (130°C) operating range of POM. The panels effectively extend the upper temperature range of the valve plastics material to enable plastic snap-fit closure valves to conform to brewery standards.

Assembly of the closure valve is illustrated by Fig. 3, the spring, support and poppet valve, omitted from the figure for clarity, are placed about the spigot 46 of valve base 44; the valve stem 35 is snap-fitted into the base spigot 46 and the valve base snap- fitted into the valve body 20. All this can be performed as a single pressing operation; the valve components being placed and aligned and then axially pressed together to lock together as a snap-fit.

In use, the closure valve 12 is screwed into the keg neck 16 (see Figs 1 and 4), the valve body thread 22, which extends for most of the length of the valve body, engaging the neck thread until the sealing ring 32 is trapped against the keg neck mouth (as shown in the top half of the figure). Also, the axial depth of the valve body propellant gas flow ports 34 is greater than the axial depth of the keg neck 16. Thus, if the closure valve is unscrewed from a pressurised keg, the length of the valve body thread 22 will ensure that the upper part of the ports 34 will emerge above the rim of the keg neck 16 whilst the lower part of the ports continue to communicate with the interior of the keg, to allow gas pressure to vent to atmosphere through the ports, before the valve body is free of the keg neck and thereby ensure that depressurisation will occur and the closure valve prevented from being forcibly ejected. Although the closure valve has been described for gas pressure dispensation of beers, closure valves in accordance with the present invention can be used for dispensation of other beverages or liquids or for negative, closed dispense instead of positive gas- pressure dispense.

Claims

CLAIMS:-

1. A valve closure for a fluid dispense system, wherein the closure valve (12) includes a body component (20) and a base component (44) and the base component and/or the base component has one or more parts (34, 56, 57, 58, 61, 62, 64, 66) shaped and configured to engage as a snap-fit features of the other component characterised in that the body component (20) and/or the base component (44) are formed from a resilient plastics material and have flexible panels (57, 62) in the body component and/or the base component, each panel having a detent (58) arranged to snap engage with a co-operating feature (34, 66) of the base component or the body component respectively.

2. A valve closure as claimed in claim 1 and wherein the closure valve is a ring-type poppet valve (12) having a body (20) , a central stem component (35), and a base (44), and further characterised in that the base (44) and/or the body (20) is shaped and configured to snap to the body and/or the base respectively and the stem (35) and/or the base is shaped and configured to snap to the base and/or the stem respectively; to trap and locate a valve member (50) and a spring (52) within the valve body.

3. A valve closure as claimed in claim 2 and further characterised in that the base (44) is formed of resilient plastics material, the base side wall has a series of axial slots (61) to define axially extending panels (57) therebetween, with each panel incorporating a radially outwardly extending detent (58) and the body (20) has ports (34) in the side thereof; so that, on assembly, as the base is fitted into the body, the panels can deflect inwardly until the detents reach the body ports and can then return outwardly so that the detents can lock as a snap-fit into the valve body ports.

4. A valve closure as claimed in claim 2 or claim 3 and further characterised in that the stem (35) is formed of resilient plastics material, the stem side wall has a series of axial slots (61) to define axially extending panels (62) therebetween and the base (44) has a radially inwardly directed shoulder (66); so that, on assembly, as the stem is fitted into the base, the panels can deflect inwardly until the detents reach the shoulder and can then return outwardly to lock as a snap-fit over the shoulder.

5. A valve closure as claimed in any of claims lto 4 and further characterised in that the resilient plastics material is a filled acetal copolymer (POM).

6. A valve closure as claimed in any of claims 2 to 5 and wherein the valve closure is for a positive gas pressure dispense system and has an externally screw threaded valve body (20) to engage the threaded neck (16) of a pressurised container (18), the valve body also having propellant gas flow ports (34) in the side thereof and further characterised in that the axial depth of the gas flow ports (34) is greater then the axial depth of the container neck (16); so that, in use, container gas pressure can vent to atmosphere before the closure valve is fully unscrewed from the container neck.