GB2041133A

GB2041133A - Quick-acting coupling, especially for gases under high pressure

Info

Publication number: GB2041133A
Application number: GB8003218A
Authority: GB
Original assignee: VSH FABRIEKEN NV
Current assignee: VSH FABRIEKEN NV
Priority date: 1979-01-31
Filing date: 1980-01-31
Publication date: 1980-09-03
Also published as: FR2448093B1; NL7900763A; FR2448093A1; GB2041133B; DE3002023A1; DE3002023C2

Abstract

Fast coupling, especially for gases under high pressure, comprises a first and second coupling part whereby in the first coupling part 1 a valve 10 is provided which is axially movable against a spring 8 and an O-ring 11, which is mounted sealingly around the valve in the casing. The O-ring 11 seals the valve 10 in the closed position. On the second coupling part 18 a nose-shaped means 19 is provided with the same outer diameter as this coupling part 18 and which diameter corresponds with the diameter of the valve 10, between the nose-shaped means and coupling part a slot 6 being provided for the out-flowing gas. <IMAGE>

Description

SPECIFICATION Fast coupling, especially for gases under high pressure The invention relates to a fast coupling, espe ciaily for gases under high pressure, comprising a coupling part, meant to be connected to a supply source such as a CO2 cylinder, and a second coupling part, meant to be connected to a pipe such as a device for dispensing beer or soft drinks.

Such a coupling is used in a CO2 pipe system, in which the vapour pressure amounts to circa 60 bar (61.2kgf/cm2) at ambient temperature.

At the moment, valves with a detachable coupling are used for this purpose.

It is the purpose of the present invention to provide a fast coupling, which is simpler and easier to handle. Although fast couplings for gases and liquids are generally known, they cannot be used for this purpose, in the first place because the known fast couplings are unsuitable for coupling and uncoupling under high pressure. Moreover, they are not hygienic and they are sensitive to dirt which may endanger the sealing.

A drawback of such a coupling is, among other things, that the O-ring used therein for sealing is pushed out of the O-ring groove under high pressure during the uncoupling. If such an O-ring construction is used in fast couplings, the drawback occurs that when the casing with O-ring travels out of the female part, the O-ring has the tendency to continue to follow the wall under the influence of the gas pressure, which is still present in the space between the two coupling parts. In this way the coupling is lifted out of its groove, so that the coupling is no longer suitable to be used again immediately.

It is the purpose of the present invention to overcome this drawback and to provide an improved fast coupling for gases under high pressure.

The fast coupling according to the invention is characterised in that in the first coupling part a valve is provided which is axially mobile against a spring and that an O-ring is mounted sealingly aroung the valve in the casing, which O-ring seals the valve in the closed position, and that at the front side of the coupling means a nose-shaped means is provided with the same outer diameter as this coupling means and which diameter corresponds with the diameter of the valve, a slot being provided between the nose-shaped means and the coupling means for the outflowing gas, all this in such a way that the passage of the gas becomes possible only after the slot opening has passed the O-ring, the O-ring remaining enclosed in the opened and the closed position of the valve.

This gives the advantage that the O-ring will always remain enclosed, both in the coupled and in the uncoupled position.

Another embodiment of the fast coupling of the invention, in which the second coupling part is a filling nipple, is characterised in that the second coupling part is a filling nipple and that the nose-shaped means is a spring-loaded valve, within which an axially mobile means is provided, which is an adapter with the same diameter as the valve and the spring-loaded valve, which adapter, when the coupling is tightened, pushes the valve further open after the spring loaded valve lies against the front side of the casing of the first coupling part, on the head of the casing of the filling nipple a slot being provided for the passage of the liquid CO2 which passes through during the filling.

This gives the advantage that a larger passage opening is obtained during the filling, whereas the higher viscosity of the CO2 in the liquid phase as compared to the gaseous phase would otherwise considerably prolong the filling time.

The invention will be explained hereinafter with reference to the drawings, in which, by means of example, an embodiment of the fast coupling according to the invention is shown.

In the drawings: Figure 1 shows in section a fast coupling according to the invention, the upper part of the drawing showing the coupling in a coupled position and the lower part of the drawing showing the coupling in an opened position; and Figure 2 shows in section an embodiment of the fast coupling according to the invention, the upper part of the drawing showing the coupling in a coupled position and the lower part of the drawing showing the coupling in an opened position.

Fig. 1 shows a coupling having two coupling parts. The first coupling part 1 is meant to be screwed onto a supply source such as a CO2 cylinder and is provided with a breaking safety plate 2, 3, 4 for safety purposes in the event of an excess pressure occuring. An axially mobile valve 10 is kept in its closed position by means of a spring 8 with a spring guide 9 and is sealed against gases by means of an O-ring 11 provided in the casing 1. The second coupling part consists of a threaded swivel 12 and provided therearound a cover 14 synthetic materal and a connecting nipple 1 5 for the connection to the CO, pipe.Furthermore this second coupling part comprises a connecting means 16, a connecting nipple 17 and a nose-shaped means 19 provided on the coupling part 18, between which noseshaped means and the coupling part a slot 6 is provided. Friction plates are indicated by the reference number 13. In the upper part of the drawing the coupling is shown completely engaged and in this position a free passage of the gas is possible, as is shown by the dotted arrow 7. As the nose-shaped means 19 and the coupling part 18 have the same diameter as the valve 10, the function of the valve as carrier of the sealing is taken over by the coupling part 18 when the latter is slid to the left in an axial direction during coupling.

Thus, the O-ring is prevented from being lifted out of its seat under pressure. In order to have a free passage of the gas from the cylinder to the drawing device in the coupled position, a slot 6 has been formed between the coupling part 18 and the nose-shaped means 19 and the gas can flow away through the cross drillings in the nose-shaped means 1 9. This slot is of such dimensions, that when it passes by the O-ring during the coupling, it presents no risk of damaging the O-ring.

The first coupling part shown in Fig. 2 is the same as in Fig. 1 and it has the same reference numbers. The second coupling part is a filling nipple. The spring-loaded valve 219 takes over the function of the noseshaped means 19 in Fig. 1. During the coupling the means 222 pushes open the valve 10 and the spring-loaded valve 219 follows this movement under the influence of the spring 220 until the spring-loaded valve 219 hits the casing of the left coupling part. The sealing has been taken over by the springloaded valve 219, which cannot travel further because of the cam at the front side of the casing 1. When the coupling has been screwed in further, the means 222 will further push open the valve 10, so that a slot is created which is sufficiently large to let the liquid CO2 pass through. The means 222 has the same diameter as the spring-loaded valve 219 and the diameter of the valve 10 in order to push open the valve 10 so as to enable a flow through the valve. The casing 217 has a slot cut into its head, through which the liquid CO2 flows into the cylinder during the filling (as shown by the arrow in the upper part of the drawing, in which the coupling is shown in coupled position). The bottom part of the drawing shows the fast coupling before the coupling has taken place.

Claims

1. Fast coupling, especially for gases under high pressure, comprising a first coupling part means to be connected to a supply source such as a CO2 cylinder, and a second coupling part meant to be connected to a pipe such as a device for dispensing beer or soft drinks, wherein in the first coupling part a valve is provided which is axially mobile against a spring and that an O-ring is mounted sealingly around the valve in the casing, which O-ring seals the valve in the closed position, and that at the front side of the coupling part a nose-shaped means is provided with the same outer diameter as this coupling part and which diameter corresponds with the diameter of the valve, between the nose-shaped means and the coupling part a slot being provided for the outflowing gas, all this in such a way that the passage of the gas becomes possible only after the slot opening has passed by the O-ring, the O-ring remaining enclosed in the opened and in the closed position of the valve.

2. Fast coupling according to claim 1, wherein the second coupling part is a filling nipple, the nose-shaped means having a spring-loaded valve, within which an axially mobile means is provided, which is an adapter with the same diameter as the valve and the spring loaded valve, which adapter, when the coupling is tightened, pushes the valve further open after the spring-loaded valve lies against the front side of the casing of the first coupling part, on the head on the casing of the filling nipple a slot being provided for the liquid CO2 which passes through during the filling.

3. Fast coupling substantially as herein described with reference to the accompanying drawings.