EP0630349B1

EP0630349B1 - Safety keg assembly

Info

Publication number: EP0630349B1
Application number: EP93906700A
Authority: EP
Inventors: Robert Bernard Cook
Original assignee: Universal Equipment Co London Ltd
Current assignee: Micro Matic AS
Priority date: 1992-03-21
Filing date: 1993-03-18
Publication date: 1996-11-20
Anticipated expiration: 2013-03-18
Also published as: ES2096280T3; AU3760893A; GB9206212D0; GB9418943D0; GB2279340A; EP0630349A1; WO1993019003A1; GB2279340B

Abstract

A safety keg assembly includes a keg (1) having a keg neck (3) and a keg spear valve (5) releasably fitted in the keg neck (3). The spear valve (5) has at least one outwardly projecting locking element (7) which co-operates with the keg neck (3). Once the keg spear valve (5) is inserted into the keg neck (3), the locking element (7) prevents the spear valve (5) from being blown out by residual pressure by engaging a shoulder (8) on the keg neck (3). The assembly and disassembly of the spear valve (5) and the keg neck (3) is by means of a slot (11) in the shoulder (8) of the keg neck (3) through which the locking element (7) can pass.

Description

This invention relates to a safety keg assembly including a keg and a safety spear valve and also to a safety spear valve.
A beer keg is usually a substantially cylindrical drum having a mouth at one end which is closed by a spear valve assembly providing access to beer in the keg via a tapping head. The spear valve assembly usually comprises a beer valve located in the keg neck which includes a valve body and a valve housing, and a downtube connected to the valve body which extends into the keg. On site, a tapping head is connected to the spear valve providing pressure in the form of CO₂, allowing the beer to be supplied under pressure to a dispensing tap at the bar.
We have found that problems can occur when the spear valve is being removed from the keg if there is residual CO₂ pressure within the keg. If this gas is not evacuated prior to an attempt to open the keg, it can result in the spear valve being blown out of the keg by the residual gas. This is, of course, very dangerous and likely to cause injury, particularly in the event of unauthorized or unskilled attempts at removal of the spear valve.
This problem has been addressed before, for example, in GB-2188040 where a projection is provided on the valve assembly which engages against the inside of the keg neck in the event of a release under pressure.
In that design, however, there is an awkward assembly arrangement whereby the valve housing and valve body must be coupled together after the valve body with the downtube thereon has been inserted through the keg neck.
US4509663 (Fallon) discloses an assembly according to the preamble of claims 1 and 6, wherein a keg neck has a blind receiving groove for a lug that extends from a collar for securing a spear valve in the keg neck. The lug keys into the groove which comprises an upper and lower vertical section at each end of a horizontal section.
An object of the present invention is to provide an improved safety keg assembly reducing the risk of a spear valve assembly being accidentally ejected by residual pressure. According to the present invention, there is provided a safety keg assembly comprising a keg having a keg neck, and a keg spear valve assembly releasably fitted in the keg neck, the keg neck having at least one abutment surface having a slot therethrough and the spear valve assembly including a plurality of locking elements axially and circumferentially spaced relative to one another and dimensional to pass through the slot whereby the keg neck and spear valve assembly cooperate together to prevent the spear valve from being blown out by residual pressure in the keg.
Thus, if it happens that one locking element is aligned with the slot when a residual pressure causes the spear valve to blow out, the ejection of the spear valve will be prevented by another element, spaced from the slot, engaging the shoulder.
Preferably the co-operable abutment surfaces comprise an abutment shoulder on the keg neck having a slot therethrough and at least one projecting locking element on the spear valve assembly dimensioned to pass through the slot.
The invention also includes a safety keg assembly comprising a keg having a keg neck, and a spear valve releasably fitted in the keg neck, the spear valve having a plurality of locking elements located on and extending outwardly therefrom, the locking elements being axially and circumferentially spaced relative to one another and being arranged such that, once the keg spear valve is inserted into the keg neck, the locking element will prevent the spear valve from being blown out by residual pressure by engaging a shoulder on the keg neck, the assembly and disassembly of the spear valve and the keg neck being facilitated by a slot in the shoulder of the keg neck through which the locking elements can pass. In that way, the spear valve and keg can be assembled and disassembled without the need for special tooling and a safety device is provided to prevent the spear valve from being blown out of the keg. The invention also includes a spear valve for the keg assembly as aforesaid and a keg including an access slot for receiving such a spear valve.
In a preferred embodiment, two locking elements are provided, spaced axially and circumferentially, relative to one another.
In the most preferred embodiment, two locking elements are provided, the elements being spaced axially from each other and being arranged to be diametrically opposite each other on the spear valve.
The keg may be provided with a plurality of shoulders spaced axially relative to each other to form one or more channels therebetween, with slots through which the or each locking element can pass. Preferably the slots in respective shoulders are spaced circumferentially relative to each other. In a preferred embodiment, the slots in respective shoulders are arranged with substantially the same circumferential and axial displacements therebetween as the circumferential and axial displacements between respective locking elements on the keg spear valve.
If desired, two locking elements and two shoulders may be provided, the shoulders being spaced axially relative to each other, and the two locking elements being spaced axially relative to each other. In this arrangement, the locking elements are diametrically opposed and the slots in the two shoulders are diametrically opposed.
The invention will now be described by way of example with reference to the accompanying drawings in which:

Figure 1 is a cross-section of one embodiment of a keg spear valve assembly in accordance with the invention, the keg neck being shown dotted and the keg body shown dotted and broken away;
Figure 2 is a perspective view of part of the spear valve assembly shown in Figure 1;
Figure 3 is a cross-section of an alternative embodiment of the invention applied to a different design of spear valve assembly to that shown in Figure 1;
Figure 4 is a perspective view of part of the spear valve assembly shown in Figure 3;
Figure 5 is a perspective view of the keg neck of the keg for use with the spear valve assemblies of Figures 1 and 3;
Figure 6 is a plan view of the keg neck shown in Figure 5;
Figure 7 is a diagrammatic plan view of a spear valve assembly showing the projecting locking elements; and
Figure 8 is a plan view of the spear valve assembly of Figure 7 inserted in the keg neck in the 'half open' position.

In the drawings a keg (1) has a body (2) and a keg neck (3) defining a mouth (4). The mouth (4) of the keg (1) is closed by a spear valve assembly (5) releasably seated within the mouth (4). In order to prevent the spear valve assembly (5) from being accidentally ejected from the keg (1) by residual pressure within the keg (1) at the time of release, the spear valve assembly (5) and keg (1) are provided with a co-operable safety device (6). The safety device (6) comprises locking elements (7) on the spear valve assembly (5) and an abutment shoulder (8) on the keg neck (3).
The keg neck (3), see Figures 5 and 6, is a hollow cylinder having a smooth inner portion (9) and a threaded inner portion (10). The abutment shoulder (8) is formed on the smooth inner portion (9) and is substantially annular extending inwardly towards the centre of the keg neck (3). A slot (11) is cut out of the shoulder (8). The keg neck (3) is rigidly secured to the keg body (2), the smooth inner portion (9) being disposed adjacent the keg body (2). The keg neck (3) defines the keg mouth (4) and permits access to the inside of the keg (1).
In the embodiment of Figures 1 and 2 the spear valve assembly (5) comprises a depending downtube (12), a beer valve indicated generally at (13) and a body (14) disposed around the beer valve (13). The body (14) of the spear valve assembly (5) is substantially cylindrical and has three portions (15,16,17); a screw threaded locking ring portion (15) spaced from the downtube (12); a skirt portion (17) adjacent the downtube (12); and a smooth portion (16) located between the screw threaded portion (15) and the skirt portion (17). The locking elements (7) are formed in the skirt portion (17) and comprise metallic lugs bent out of the plane of the surface of the skirt (17). The two elements (7) are axially spaced from one another on the skirt portion (17) forming an inner locking element adjacent the downtube (12) and an outer locking element (7). The locking elements (7) are diametrically opposed and extend outwardly from the body (14) as shown. On insertion of the spear valve into the keg neck, the inner locking element (7) abuts the outer face of the shoulder (8). The spear valve (5) is then rotated until the locking element (7) aligns with the shoulder slot (11): the locking element (7) can then pass through the slot. Repeating this rotary action allows the other locking element (7) to pass through the slot (11). A bridging washer (18) is also provided, being disposed around the skirt portion (17) and located between the smooth portion (16) and the outer locking element (7), thereby providing a continuous seal reaction face, bridging the shoulder slot (11).
To assemble the spear valve assembly (5) of the first embodiment into the keg (1), the spear valve assembly (15) is inserted, downtube (12) first, into the keg (1) through the keg neck (3). The locking elements (7) in turn, abut the outer face of the shoulder (8) and the rotary action described above allows each element (7) to pass in turn through the shoulder slot (11). Once both elements (7) are past the shoulder (8), the screw threaded portions (10,15) on the keg neck (3) and valve assembly (5) respectively, threadingly engage with each other and allow the keg neck (3) and valve assembly (5) to be tightened together. Once assembled, the smooth portion (16) abuts against the washer (18) which, in turn, abuts the shoulder (8), sealing the slot (11) and thereby the keg (1).
To disassemble the valve assembly (5) from the keg neck (3) (see Figures 5 to 8), the residual pressure in the keg (1) is evacuated and the valve assembly (5) is unscrewed from the keg neck (3). When the outer locking element (7) abuts against the abutment shoulder (8), the valve assembly (5) is rotated relative to the keg neck (3) until the locking element corresponds with the slot (11) in the shoulder (8). The valve assembly (5) can then be lifted until the inner locking element (7) abuts the shoulder (8). The valve assembly (5) is again rotated until the inner locking element (7) can travel through the slot (11) and the valve assembly (5) is then free to be removed from the keg neck (3).
In the event of an attempt to disassemble the spear valve assembly (5) without evacuating the residual pressure in the keg (1), the spear valve assembly (5) can be unscrewed from the keg neck (3) and at this point the pressure build up in the keg (1) could cause a blow-out. However, as the valve assembly (5) is provided with locking elements (7), the outer locking element (7) will abut against the shoulder (8) preventing the spear valve assembly (14) from being blown out and allowing excess pressure to escape. In the unlikely event that the outer locking element (7) happens to be aligned with the slot (11) when blow-out occurs, the inner locking element (7) acts as a back-up and will itself abut the shoulder (8).
Figures 3 and 4 show a slightly different embodiment to that shown in Figures 1 and 2, the safety device being mounted on a different design of spear valve assembly. Parts corresponding to parts in Figures 1 and 2 carry the same reference numerals. The safety device is very similar to that shown in Figures 1 and 2, the device simply being adapted to an alternative spear valve assembly (20) which comprises a beer valve (21), a body (22) and a downtube (23). The body (22) comprises a smooth portion (16), a skirt (17) and a separate screw threaded locking ring portion (15). The skirt (17) is formed integrally with the downtube (23). As in the above embodiment, the locking elements (7) are axially displaced and formed diametrically opposed in the skirt (17) so as to extend radially outwardly therefrom. The keg neck (3) is substantially as described above.
The alternative design of Figures 3 and 4 is assembled and disassembled in substantially the same way as described with reference to the embodiment of Figures 1 and 2.
In both embodiments, the locking elements (7) are sections of the skirt (17) bent away from the axis of the spear valve to form lugs whereby insertion and removal of the spear valve is only possible by alignment with the or each slot in the keg shoulder as described.

Claims

A safety keg assembly comprising a keg (1) having a keg neck (3), and a keg spear valve assembly (5) releasably fitted in the keg neck,the keg neck having at least one abutment surface (8) having a slot (11) and the spear valve assembly including a plurality of locking elements (7), characterised in that the slot passes through the abutment surface and the locking elements are axially and circumferentially spaced relative to one another and dimensioned to pass through the slot (11) whereby the keg neck and spear valve assembly co-operate together to prevent the spear valve from being blown out by residual pressure in the keg.
A safety keg assembly according to claim 1, wherein the abutment surface (8) on the keg neck comprises an annular shoulder on the neck.
A safety keg assembly according to claim 1 or 2, comprising two locking elements (7) axially spaced and circumferentially spaced to one another.
A safety keg assembly according to claim 1, wherein the keg neck (3) includes a plurality of arcuate shoulders axially spaced relative to one another to form one or more channels therebetween each shoulder being arranged to provide a passage through which the or each locking element can pass, the passages being angularly displaced.
A safety keg assembly according to claim 4, wherein the passages are slots in the shoulders.
A safety keg assembly comprising a keg (1) having a keg neck (3) presenting a shoulder (8),
and a spear valve (5) releasably fitted in the keg neck, the spear valve having a plurality of locking elements (7) located on and extending outwardly therefrom, characterised by the locking elements being axially and circumferentially spaced relative to one another and being arranged such that, once the keg spear valve is inserted into the keg neck, the locking elements will prevent the spear valve from being blown out by residual pressure by engaging a shoulder on the keg neck, the assembly and disassembly of the spear valve and the keg neck being facilitated by a slot (11) in the shoulder (8) of the keg neck through which the locking elements can pass.
A spear valve (5) for a safety keg assembly according to any one of claims 1 to 6, comprising a plurality of locking elements (7) extending outwardly therefrom and being axially and circumferentially spaced relative to one another.