EP0761555A1

EP0761555A1 - Beer barrel stopper provided with an ejection preventing means

Info

Publication number: EP0761555A1
Application number: EP96300230A
Authority: EP
Inventors: Kazuo Furuichi
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-09-07
Filing date: 1996-01-11
Publication date: 1997-03-12

Abstract

A spear-tube stopper for use with pressurisable beer barrels, having an ejection preventing member. The ejection preventing member having a portion protruding from a window of the body of the stopper and having a length sufficient to engage the lower edge part of the barrel cap to prevent removal of the stopper from the barrel but being retractable by inserting a gas bulb/dispenser connecting means sufficiently into the stopper. The ejection preventing member including a hanging piece, made of stainless steel with a high elasticity modulus, whose upper part is fixed onto the upper end part of a down-tube, providing an inverted U-shaped notch onto a part of said dangling piece and bending the upper part of the notch outward like an arc to form said protruding portion.

Description

The present invention relates to a spear-tube stopper for use with a pressurised beer barrel, more specifically, to a spear-tube stopper provided with a ejection-preventing means.
Pressurised beer barrels generally employ a special stopper called a spear-tube stopper, which is used for transferring beer and pressurising carbon dioxide gas to and from the barrel and is also usable for cleaning the inside of the beer barrel.
A spear-tube stopper comprises: a body containing a spring urged beer valve, a spring urged gas valve, a beer valve spring support and a down-tube extending downwards therefrom. It is unlikely that a spear-tube stopper should need to be removed from a beer barrel in ordinary use since it is provided on the upper end part of the body and firmly fitted to the beer barrel with a male thread screwed into a female thread provided on the inside of a beer barrel cap.
However, occasionally it is necessary to remove the spear-tube stopper, for example, for cleaning and repair. If there is residual pressure in the barrel, due to insufficient exhausting of the pressurising gas, the spear-tube stopper can be violently ejected once the threads are unfastened. This often causes accidents such as injuring workers and breaking vessels.
Spear-tube stoppers provided with an ejection preventing means, for preventing them from shooting out of the barrel and thus avoiding such accidents, are known. An example of such a stopper is a spear-tube stopper provided with an ejection preventing pin which retractably protrudes from the stopper body. However, this leads to problems during cleaning, since the inside of the body is rather complicated in structure. Another example is a spear-tube stopper provided with an ejection preventing means comprising a pair of hinged metal components on the down-tube. It is necessary to tip the barrel, so that the hinges are closed, in order to remove the stopper from the barrel. However, it is difficult to apply these means to ready-made or conventionally used spear-tube stoppers.
In order to overcome these problems of the prior art it has been proposed (eg. Japanese Patent Application No. 6-192230) to provide an ejection preventing device that can be easily applied to a modified ready-made spear-tube stopper. However, there is still the problem that if a spear-tube stopper should be ejected by residual pressure in the barrel, the stopper will already have accelerated to a significant speed before the ejection preventing piece, which is provided lower down on the stopper, comes into contact with the lower side of the cap of the barrel. This may cause the ejection preventing piece to break, and hence it is necessary to make the ejection preventing piece strong with a view to preventing this.
Hence, it is desirable to provide a spear-tube stopper provided with an ejection preventing means, which provides the ejection preventing function, has a simple structure, needs less material and can be produced easily by modification of a ready-made spear-tube stopper.
According to the present invention there is provided a spear-tube stopper, for use in a pressurisable beer barrel, the stopper comprising: a body to be attached in an opening to the barrel and to extend into the barrel; a down tube having an upper part located within the body and extending down through the bottom of the body, the down tube being slidable downwardly to an extent limited by the body, the stopper including an ejection prevention member which moves with the tube and is provided with at least one projecting portion normally projecting outward such that it engages the lower side of the barrel cap as the stopper is removed from the barrel, characterised by the projecting portion being formed to extend upwards from a part of the ejection prevention member and having the upper portion bent outward through a window in the body, and being retractable by moving said ejection prevention member downwardly so that the projecting portion is forced behind a lower part of the body.
The projecting portion prevents unexpected ejection of the stopper from a barrel. The stopper can only be released if the protruding portion is retracted. This is done by pressing the tube and ejection prevention member downward relative to the body.
Preferably, said ejection prevention member is made from a material having a high modulus of elasticity such as stainless steel.
Preferably also, said ejection prevention member includes a fixing ring located at the upper end of the down-tube.
There may be a spring urging the down tube upwards into a closed position in which it is in contact with the body to prevent access to the barrel around the outside of the tube.
Preferably, the ejection prevention member is formed in one piece, the fixing ring being provided so that it is held between a flange on the upper end of the down-tube and the upper end of the spring which is urged upwards against said flange.
A specific embodiment of the present invention will now be described by way of example with reference to the accompanying drawings in which:-

Fig. 1 is a schematic cross section of a beer barrel equipped with a spear-tube stopper of the present invention;
Fig. 2 is a schematic cross section of a beer barrel equipped with a conventional spear-tube stopper;
Figs. 3A and 3B are side views of an embodiment of the present invention;
Figs. 4A and 4B are cross sections of the same embodiment;
Fig. 5 is a partial perspective view showing the main part of the same embodiment of the present invention; and
Figs. 6a-e are perspective views of an ejection preventing piece for use in a stopper of the present invention.

In Fig. 1, a beer barrel A, whose vertical cross section is shown schematically, comprises a main body 1 with a cap 4 provided thereon, an upper protector 3 and a lower protector 2 and a spear-tube stopper B according to the present invention, further shown in Figures 3A and 3B. This comprises a body 5 and a down-tube 6; a window 55 is provided on the lower part of the body 1 and an ejection preventing piece 7 with a barrel engaging portion 73 protrudes from the window.
A spear-tube stopper B shown in Fig. 2 is of a conventional type and has no ejection preventing piece.
In Figs. 3A and 3B, an ejection preventing piece 7 is shown set in a normal position. The spear-tube stopper will not eject as a result of unexhausted internal pressure in the barrel with a stopper in this state.
Figs. 4A and 4B show further details and the operation of this embodiment of the present invention. Figure 4A shows the normal state of a spear-tube stopper B in a barrel, in which it cannot be removed, and Figure 4B shows the spear-tube in its state in which it is removable from the barrel.
The barrel engaging portion 73 is provided on a downwardly depending portion 72 of the ejection preventing piece 7 and protrudes from the window 55 in an arc. Even if the screw 51 of the stopper is removed from the screw of the cap 4, the tip part of the barrel engaging portion 73 comes into contact with the lower edge part of the cap 4 and prevents the stopper B from ejecting from the barrel.
As shown in Figure 5 the ejection preventing piece 7 is formed of a fixing ring 71 to which the downwardly depending portion 72 is attached. The ring is held between a flange of the down-tube 6 and the upper end of the gas spring 52. The downwardly depending portion 72 and the barrel engaging portion 73 are located within the lower part 54 of the body 1 near window 55. They are formed from a metal sheet in one piece, although this is not essential. For example, a separately prepared ejection preventing piece may be welded to the upper end flange of the down-tube 6. In addition, it is possible to provide a pair or more of barrel engaging portions 73.
Figure 4B shows the case of removing the stopper B from the barrel A. The down-tube 6 is pushed down using a special implement similar to a dispenser head but with no connecting stopper to a gas bottle or a dispenser provided thereon. This pushes the ejection preventing piece 7 down and the downwardly depending portion and the barrel engaging portion 73 are pushed behind the lower part of the body below the window 55. As a result the portion 73 moves radially inwards and will no longer prevent withdrawal. The stopper B can then be withdrawn from the cap 4 without restriction. Under these circumstances, even if there exists residual gas in the barrel A, it escapes through the large space between the gas valve and the stopper body and is completely discharged; hence the stopper B does not shoot out of the barrel.
Fig. 6 shows various ejection preventing members with modified examples of the barrel engaging portion. If residual pressure is less than about 5 bar the barrel engaging portion 73 with the planar cross section, shown in Fig. 6a, is satisfactory. However, it may be desirable to make ones with modified cross sections with higher rigidity, as shown in Fig. 6b-e, to allow for emergency situations.
Therefore the present invention provides a means to prevent accidents due to spear-tube stoppers shooting out of barrels, which utilises a ready-made spear-tube stopper provided with an extremely simple additional mechanism.

Claims

A spear-tube stopper (B), for use in a pressurisable beer barrel (A), the stopper comprising: a body (1) to be attached in an opening to the barrel and to extend into the barrel; a down tube (6) having an upper part located within the body and extending down through the bottom of the body, the down tube being slidable downwardly to an extent limited by the body, the stopper including an ejection prevention member (7) which moves with the tube and is provided with at least one projecting portion (73) normally projecting outward such that it engages the lower side of the barrel cap as the stopper is removed from the barrel, characterised by the projecting portion (73) being formed to extend upwards from a part of the ejection prevention member (7) and having the upper portion bent outward through a window (55) in the body, and being retractable by moving said ejection prevention member downwardly so that the projecting portion is forced behind a lower part of the body.
A stopper according to claim 1 wherein said ejection prevention member (7) is formed from a material having a high modulus of elasticity.
A stopper according to any one of claims 1 or 2 wherein said ejection prevention member (7) is made of stainless steel.
A stopper according to any one of claims 1 to 3 wherein said ejection prevention member includes a fixing ring (71) located at the upper end of the down-tube (6).
A stopper according to any one of the preceding claims including a spring (52) urging the down tube upwards into a closed position in which it is in contact with the body to prevent access to the barrel around the outside of the tube.
A stopper according to claim 4 and claim 5, in which the ejection prevention member (7) is formed in one piece, the fixing ring (71) being provided so that it is held between a flange on the upper end of the down-tube (6) and the upper end of a the spring (52) which is urged upwards against said flange.
A stopper according to any one of the preceding claims including a valve located within the down tube and spring urged upwards towards a position in which it closes the upper end of the down tube.