GB2184103A

GB2184103A - Valve fitting

Info

Publication number: GB2184103A
Application number: GB08629898A
Authority: GB
Inventors: Henry Gotch
Original assignee: GRUNDY
Current assignee: GRUNDY
Priority date: 1985-12-16
Filing date: 1986-12-15
Publication date: 1987-06-17
Anticipated expiration: 2006-12-15
Also published as: GB2184103B; AU6776087A; GB8629898D0; WO1987003573A1; ES2003756A6; DK425187D0; EP0290440A1; DK425187A; CN86108806A

Abstract

A valve fitting for the bung hole outlet (51) of a cask (50) has a body part (54) carrying the valve assembly (56, 57) and extractor tube (55). Threading (62) engages the internal threading (52) of the outlet (51). The top plate (59) of the fitting is a separate ring which engages the threading (52) by threading (60). This arrangement provides a safeguard against removal of the fitting from the cask. Removing the top plate (59) leaves the valve assembly (53) intact with no means of applying purchase to achieve unscrewing of the fitting. A special tool may be used to remove the fitting (53) if required.

Description

SPECIFICATION Liquid extraction outlets for beverage containers This invention relates to an improved construction of liquid extraction outlet for a beverage container such as a cask or keg for beer.

The invention is particularly concerned with a means for preventing unauthorised removal of the liquid extractor tube valve assembly from the outlet housing of a cask.

In known constructions a cask or keg has an upstanding collar forming the bung hole outlet which is internally threaded to receive a liquid extractor tube and associated valve fitting. The valve fitting usually defines passageways for inlet of gas to the cask and for outlet of beverage and a cooperating coupling head connects with the fitting and the outlet.

Connection of the coupling head may be made by engagement of lugs on the fitting with inclined peripheral detent parts of the coupling head to give a form of bayonet locking action.

Alternatively, engagement can be with a top plate forming a flange on the collar, parts of the coupling head embracing and engaging beneath the flange. The so-called "tri-lobe" fitting is of this kind. A disadvantage with such constructions is that it is possible to use a tool or even the coupling head itself to engage side faces of the lugs or the flange thereby to unscrew the valve fitting complete with extractor tube from the cask body. In any event the lugs on the valve fitting provide a simple means for engagement by some form of spanner or other tool whereby removal of the fitting and hence extraction of the contents may be made.

A further disadvantage of the known prior art constructions is that unscrewing the valve fitting unit can lead to a dangerous situation wherein the internal gas pressure can blow the whole fitting suddenly out of the cask in the final stages of unscrewing with risk of serious injury.

Referring to Figs. 1 and 2 of the accompanying drawings these show one prior art construction of valve fitting housing to which the improvement of the invention relates. As shown in this drawing a fitting comprises an upper portion 1 which includes a valve seat 2 which in use is engaged by a rubber annular valve member urged into engagement with the seat by means of a spring (not shown). A skirt portion 3 is welded to the part 1 at 4 and this houses the valve assembly, valve spring means and top end of the liquid extractor tube. In use, this assembly drops into the bung hole outlet of a cask and screw thread 5 on the body part 1 engages a complementary screw thread on the internal periphery of the bung hole housing. The valve fitting assembly is screwed down firmly into the bung housing to form a closure.In order to introduce pressurised gas into the cask and to extract liquid therefrom a coupling head (not shown) engages with the part 1 and this is achieved by means of lugs 6 engaging detents in the coupling head having inclined peripheral ramp portions the leading edges of which may engage beneath the lugs 6 and the coupling head can then be rotated during which action it is forced down to open the valves within the head fitting thus broaching the cask.

However, as will be appreciated, it is a relatively easy matter to unscrew the fitting 1 from the cask thereby enabling the contents to be extracted easily through the open bung hole housing. This can obviously be achieved by engaging some form of spanner with the lugs 6 or, more simply, by partially engaging the coupling head so that parts thereon abut flank surfaces of the lugs 6 whereby the coupling head itself may be used as a spanner to unscrew the fitting.

This invention seeks to provide a fitting, not essentially limited to the above described kind, which provides better safety, security and which deters pilfering. This invention also provides a method of modifying existing fittings so as to make their removal from a bung hole housing more difficult.

According to this invention there is provided a valve fitting for securing within the outlet of a cask or the like which fitting has means for engagement with a coupling head the fitting being characterised by a separate second fitting part which may be engaged with the housing after engagement of a first fitting part carrying a valve assembly, the second fitting part having the means for engagement with the coupling head.

More specifically there is provided a valve fitting for securing within the outlet of a cask the fitting having portions forming means for engagement with a coupling head to bring said head into operative connection with a valve assembly carried by the fitting, said fitting being characterised by a first part carrying said valve assembly which part may be secured in or removed from the outlet only by means of a special (non-standard) tool and a second part which may be secured in the outlet, said second part carrying said portions forming means for engagement with a coupling head.

With such a construction the separate ring part carrying the engagement means for the coupling head, if removed, leaves behind the valve fitting part itself which does not include any detents or formations which may be easily engaged by a spanner or the like to assist removal. Removal of the valve fitting part may nevertheless be effected and one method of achieving this is to provide detents or other formations on an internal surface which is normally below the valve seating. A special tool may then be engaged, in accordance with a further feature of the invention, with the fitting part to depress the valve against spring pressure thereby allowing projecting portions of the tool to engage the formations whereby rotary motion imparted to the tool may unscrew the fitting part.In an alternative method, a special tool is provided which may be expanded or clamped with sufficient force to frictionally engage a surface of the fitting part to apply the necessary rotational torque to unscrew the fitting.

This invention also provides a method of modifying an existing valve fitting to form an improved valve fitting according to any preceding claim in which method an upper portion of the fitting carrying the engagement means for the coupling head is removed from the lower valve carrying body portion to which, if necessary, a threaded ring is secured enabling said valve carrying body portion to be engaged with the internal threading of a cask outlet housing.

This invention is further described and illustrated with reference to the further figures of drawings, wherein: Figure 3 shows a longitudinal section through a valve fitting, the upper portion showing the fitting modified according to this invention, whereas the lower half shows the unmodified fitting, Figure 4 shows the fitting according to Fig.

3, looking in the direction of arrow A, Figure 5 shows a complete valve fitting of the kind having a tri-lobe top coupling plate, Figure 6 shows a plan view of the fitting of Fig. 3, Figure 7 shows an end view of one form of special tool to unscrew the fitting of Figs. 3 and 4, Figure 8 shows the fitting of Fig. 7 in longitudinal section, Figure 9 shows in end view a special tool for unscrewing the fitting of Figs. 5 and 6, Figure 10 shows in longitudinal section the special tool of Fig. 9, before engagement, Figure 11 shows the special tool of Fig. 9 after engagement with a fitting body similar to Fig. 5, and Figure 12 shows a further special tool for use with the fitting of Fig. 5.

The embodiment of the invention shown in Figs. 3 and 4 of the accompanying drawings illustrates modifications applied to a fitting of the kind previously described in connection with Figs. 1 and 2 of the drawings, the same reference numerals being applied. Referring to the further drawings, Fig. 3 shows in longitu dinal section the top of the valve fitting 1 excluding the skirt portion 3. The lower half of this drawing illustrates the unmodified fitt ing whereas the upper half shows the modified construction.

The method of modifying the fitting com prises cutting the top part of the valve body 1 along a line X-X thereby to provide a sepa rate annular ring 7. This ring is provided with a screw threading 8 on its outer peripheral surface and includes the lugs 6 for engagement with the coupling head. The body part 1 is modified by providing an annular screw threaded ring 5 welded thereto and by this means the two separate portions of the fitting part may be engaged with the bung hole housing. The threading 5 which is now carried by a separate ring can be brazed to the top portion 1 of the fitting.In order to enable the part 1 of the fitting to be removed the tapered valve seating surface 2 is-provided with three recesses 9 formed by a milling operation with the recesses being positioned so that they are below the top of the sealing surface and hence do not interfere with the sealing action. The recesses 9 are thus positioned so that they are sufficiently far below the top of the sealing surface not to interfere with the seal made but not so far below that they cannot be engaged by a suitable special tool through depression of the central valve. In practice the distance by which the central valve may be depressed is limited through binding of the valve coil spring and hence the positioning of the recesses needs to be carefully controlled.

Fig. 4 shows an underneath view of the fitting illustrating the positioning of the three recesses 9 in relation to the valve seating surface 2.

In order to remove the fitting part 1 a suitable special tool is provided having a nose which will pass through the aperture and which can be forced down to compress the valve and lift same from a seat 2. The tool includes three dogs which may then be caused to expand outwardly to abut the valve surface 2 and when the tool is rotated a position will be ultimately reached where the dogs snap into engagement with the three recesses 9 thus ailowing considerable torque to be applied to the fitting in order to remove or tighten same. One such tool is hereinafter described with reference to Figs. 7 and 8 of the drawings. As may be seen the portion of the ring 7 carrying the lugs 6 is separate and if any attempt is made to tamper with the cask this ring can be relatively easily removed but it will then leave the part 1 remaining in the housing with no obvious means of removal and moreover with no portions visible or accessible which could be engaged by a normally available tool.

Although the present invention has been described in conjunction with a "well type" fitting, the principal can equally well be applied with a fitting of the so called "tri-lobe" kind by adopting the same principal which is to make the parts cooperating with the coupling head removable on a separate ring whilst leaving behind the fitting which houses the valve.

The valve fitting may then incorporate concealed abutments, recesses, plain surfaces or the like for engagement with a suitable special tool.

Figs. 5 and 6 of the drawings show a section through such a "tri-lobe" coupling according to the invention. As shown the top 50 of a cask or keg has an upstanding collar 51 forming a bung hole outlet. The collar has internal threading 52 which engages threading 62 on an extractor tube valve assembly 53 comprising a body 54 carrying an extractor tube 55 with a valve 56 urged by spring 57 to close the top aperture 58. A coupling head (not shown) engages with the fitting to depress the seal 56.

To effect coupling the head (not shown) embraces the outer peripheral parts of a top plate 59 which has a trilobal shape in plan (see Fig. 6). The plate 59 has a screw threading 60 engaging the threading 52 of the collar 51. With this arrangement if an attempt is made to remove the fitting 53 all that happens is that the plate 59 is removed leaving a smooth surfaced top to the fitting only. There is no means by which a conventional tool can be engaged to apply enough force to unscrew the top.

The plate 59 has an inclined inwardly facing surface 63 complementary to a surface 64 on the body part. These surfaces provide for a frictional engagement between the two parts.

The body 54 is sealed by a resilient ring 65 engaging between shoulder 66 of the body and wall 50 of the cask. The extractor tube 55, body 54 and valve assembly 56,57 comprises a complete unit which may be screwed into the outlet 51 with only the coupling head engaging parts carried by the separate ring 59. This is a feature which can be applied to all embodiments.

By using a special tool, however, the fitting can be removed. This may be effected in one version by frictionally engaging internal surfaces 61 of the fitting by depressing the seal 56 to afford sufficient access for a radially expanding segmented tool to be engaged.

In a second version a special tool is provided which clamps the inner peripheral rim 67 on the inside and outside surfaces. Such a tool is described hereoinafter with reference to Figs. 9 to 11.

In a third version a special tool is provided with extending legs which engage the three equispaced parts 68, such a tool being shown in Fig. 12.

One of the most advantageous features of the present invention is that the method is applicable to known fittings which can thus be modified in a relatively simple and cheap manner to provide a high security device without the necessity of completely changing the valve assembly and body or coupling head. The method of rendering the coupling tamper proof operates rather surprisingly because it has been found in practice that the internal threading on the bung hole outlet housing of known casks is deeper than is strictly required to effect coupling wifth the known valve body. This thus enables the existing valve housing to be cut and for the threading thereon to be displaced lower down the body whilst still offering full engagement with the bung hole outlet housing. This then leaves sufficient threading exposed in the collar for coupling with the top plate part of the fitting.

A further incidental feature of the invention is that the top ring which carries the lugs or coupling plate can be changed easily should there be any damage and furthermore the geometry of the lugs could be varied to enable the cask to be used with certain coupling heads only if this should be required.

An advantage also accrues in that, for safety, when the fitting part carrying the valve assembly is removed it is essential to either remove the seal first or open the valve to introduce the special tool. This thus degasses the cask before the fitting is unscrewed.

Special forms of tool to be used for removing the valve fitting are now described. Referring firstly to Figs. 7 and 8 of the drawings, these show a tool having a body portion 70 with an integral nose 71 of diameter such that it will fit into the aperture of the valve fitting 1 shown in Fig. 3. This is of course affter the separate ring 7 carrying the coupling head engaging lugs 6 has been removed from the cask outlet. The nose 71 serves to displace downwardly the valve fitting components whereby three laterally extending dogs 72 may locate below the upper portion of the valve seating surface 2 (Fig. 3). A central plunger 73 carrying a conically tapered plug 74 is moved downwardly within the nose 71 thus causing the three dogs 72 to be moved outwardly to the position shown in Fig. 8.

The special tool may be rotated and by applying spring loading 75 a position will be reached wherein the dogs 72 snap into the detents 9 (Fig. 3) thereby forming a positive engagement and enabling the valve fitting part 1 to be unscrewed by rotation of the body 70.

Figs. 9 and 10 show a special tool which may be used with a valve fitting of the kind shown in Fig. 5, this tool comprising three segments 90 having outwardly directed flange parts 91 which in cooperation with a surface 92 of a body part 93 form a clamp. Positioned within the segments 90 is a plug 94 which may be moved downwardly relative to the segments and body 93. The way in which this special tool operates is illustrated in Fig.

11 which shows a valve fitting essentially similar to that of Fig. 5 but in which the seal engaging lip 67 in Fig. 5 is displaced more inside the fitting. Referring to Fig. 11, the valve fitting body 110 includes the valve seating surface 111 and this is engaged from the underside by the flanges 91 on the segments 90. This is achieved by withdrawing the plug 94 so that the segments collapse inwardly and may then be introduced into the fitting following which the plug 94 is moved downwardly to expand the segments outwardly into the position shown in Fig. 11. Following this the body part 93 is moved relatively towards the flanges 91 by a screw arrangement thereby to firmly clamp the flange 111. After this action the whole tool may be rotated so as to remove the valve fitting 110 from the cask outlet.

The segments 90 and the body 93 are arranged by virtue of the screw threading engagement such that turning one by means of a spanner or other tool whilst retarding the rotation of the other will cause the clamping action to be increased in one direction whereas reversing this by holding the other part and relatively retarding the first part will cause the clamping action to be increased when rotation is in the opposite sense.

Fig. 12 shows a further special tool for removing the valve fitting body 54 as shown in Fig. 5. In this arrangement a plug member 120 includes three legs 121 which are equispaced around the periphery. These legs slide in channels 122 within the body 120 and initially the legs 121 are withdrawn into the body. In this position, the body 120 can be inserted through the valve fitting opening defined by the rim 67 and thereafter extended so that each leg 121 passes through an aperture 68 of which three are provided equally spaced around the wall of the valve fitting body 54. When the body 120 is rotated the legs 121 contact flank surface of each aperture 68 and by this means the fitting body may be unscrewed from the cask outlet.

In the arrangements shown in Figs. 9 to 11 the special tools may be engaged to remove the valve fitting part without removing the valve seal itself. In these constructions the special tool serves initially to depress the valve seal (56 in Fig. 5) against spring pressure. In the embodiment of Fig. 12 the valve fitting parts are upset and removed prior to engagement by the special tool unit.

Claims

1. A valve fitting for securing within the outlet of a cask or the like which fitting has means for engagement with a coupling head the fitting being characterised by a separate second fitting part which may be engaged with the housing after engagement of a first fitting part carrying a valve assembly, the second fitting part having the means for engagement with the coupling head.

2. A valve fitting for securing within the outlet of a cask the fitting having portions forming means for engagement with a coupling head to bring said head into operative connection with a valve assembly carried by the fitting, said fitting being characterised by a first part carrying said valve assembly which part may be secured-in or removed from the outlet only by means of a special (non-standard) tool and a second part which may be secured in the outlet, said second part carrying said portions forming means for engagement with a coupling head.

3. A valve fitting in accordance with Claim 1 or 2, wherein the first fitting part has screw threading to engage complementary screw threading in the cask outlet, the second part having screw threading to engage the threading in the cask outlet and preferably a surface which abuts the first fitting part.

4. A valve fitting in accordance with Claim 1 or 2 or 3, wherein the first fitting part includes inwardly directed lugs or other formations to engage a coupling head.

5. A valve fitting in accordance with Claims 1 or 2 or 3, wherein the first fitting part comprises a plate portion to engage with a coupling head, the plate portion being integral with a ring portion to engage the cask outlet.

6. A valve fitting in accordance with Claim 5, wherein the plate portion is tri-lobular in plan.

7. A valve fitting in accordance with Claim 5 or 6, wherein an inwardly directed surface of the ring portion engages a complementary outwardly directed surface of the fitting part.

8. A valve fitting in accordance with Claim 7, wherein said surfaces are tapered and inclined relative to the threading.

9. A valve fitting in accordance with any preceding claim wherein the first fitting part has a surface below a seating provided for the valve assembly, said surface being engageable by an outwardly expanding part of a special tool which may thereafter be rotated to remove the first fitting part from the outlet of the cask.

10. A valve fitting in accordance with Claim 9, wherein said surface includes detents (depressions or projections) which may be engaged by outwardly expanding or extending dogs on the special tool.

11. A valve fitting in accordance with Claim 10, wherein the special tool includes a nose to depress a valve part of the valve assembly, the nose carrying dogs which may extend laterally to engage the detents.

12. A valve fitting in accordance with Claim 9, wherein the first fitting part has an inwardly directed annular rim forming a seating for the valve assembly, the special tool having a segmented nose part which depresses the valve from the seating and thereafter expands radially to locate beneath said rim, a body part of the special tool being brought into abutment with the upper surface of the rim to clamp the rim between the nose and body whereby the tool may be rotated to remove the first fitting part.

13. A valve fitting in accordance with Claims 9, wherein the first fitting part includes apertures or fluid flow ports, the special tool having a body to enter the said fitting part and extendable legs which may be deployed from the body to enter each through a respective aperture to contact a surface of each aperture, whereby the said body may be rotated to remove the first fitting part by virtue of the legs engaging said surfaces of the apertures.

14. A method of modifying a valve fitting to form an improved valve fitting according to any preceding claim in which method an upper portion of the fitting carrying the engagement means for the coupling head is removed from the lower valve carrying body portion to which, if necessary, a threaded ring is secured enabling said valve carrying body portion to be engaged with the internal threading of a cask outlet housing.

15. A method in accordance with Claim 14, wherein the removed upper portion is adapted, if necessary, and used as the second fitting part having the means for engagement with the coupling head.

16. A valve fitting for a cask substantially as described herein and exemplified with reference to Figs. 3 to 5 of the drawings.

17. A valve fitting for a cask substantially as described herein and claimed and in combination with a special tool as described herein and exemplified with reference to Figs. 7 to 12 of the drawings.

18. A method of modifying a valve fitting as described herein and exemplified.