GB2199127A

GB2199127A - Gas bottle closure

Info

Publication number: GB2199127A
Application number: GB08628683A
Authority: GB
Inventors: Alistair Scott
Original assignee: Isoworth Ltd
Current assignee: Isoworth Ltd
Priority date: 1986-12-01
Filing date: 1986-12-01
Publication date: 1988-06-29
Anticipated expiration: 2006-12-01
Also published as: GB2199127B; GB8628683D0

Abstract

A gas bottle closure 2 for a carbon dioxide bottle 8 for home carbonation apparatus is provided with a gas escape passage 36 which is separate from the gas supply passage 34 which communicates with the carbonation apparatus in use. A burstable membrane 38 is secured across an axial portion of the escape passage which communicates with a pair of radially extending portions 44 which lead to atmosphere. This arrangement is more compact than the prior art and provides escape of gas direct to atmosphere when the membrane breaks as a consequence of excessive pressure in the bottle. <IMAGE>

Description

GAS BOTTLE CLOSURE This invention relates to gas bottle closures and is particularly concerned with closure for bottles containing gas under pressure, such as pressurised Co2 bottles for use with home carbonation-apparatus.

Known gas bottle closures for use with home carbonation apparatus comprise a body, a connector at one end of the body for attachment to the carbonation apparatus, a gas supply passage for connecting the interior of the bottle to the connector, a valve for controlling the supply of gas through the gas supply passage, the valve including an actuating member engageable by a valve operating plunger provided in the home carbonation apparatus, a gas escape passage in the body, and a membrane which normally closes the gas escape passage and which is burstable under excessive gas pressure in the bottle in order to relieve such excessive pressure.

In one known closure, the valve is disposed within the body adjacent the connector and the gas supply passage is coaxial with the body. The gas escape passage branches from the gas supply passage in a radial direction and the membrane is secured in a plane at right angles to the radial gas escape passage. As a consequence of this arrangement of the membrane, the axial length (normally the height) of the body has to be greater than desirable in order to accommodate the membrane. In turn, the closure takes up more space than desirable so that the size of the bottle has to be reduced in order for it to be accommodated in a carbonation apparatus of given size.

In an alternative arrangement described in UK Patent Specification No 2,136,104, the valve is disposed at the opposite end of the body to the connector and a valve actuating rod extends through the gas supply passage, which is coaxial with the body, to the connector so that the valve may be operated by the valve actuating plunger of the carbonation apparatus.

The gas escape passage is formed within the valve operating rod and consequently opens into the connector. This arrangement suffers from the severe disadvantage that, whilst the gas escape passage does provide venting of excess gas pressure to atmosphere if the membrane bursts before the bottle is attached to a carbonation apparatus, it does not do so if the bottle is mounted in the carbonation apparatus with which it is to be used. On the contrary, in this situation, the gas escape passage merely connects the interior of the gas bottle to the interior of the carbonation apparatus which may cause the entire machine to explode.

The invention solves these problems by providing the gas escape passage in the body separately from the gas supply passage, and with its outer end leading to atmosphere at the periphery of the body, the burstable membrane extending across the inner end of the gas escape passage.

The invention is described further by-way of example with reference to the accompanying drawing, which is a section through a gas bottle closure according to a preferred embodiment of the invention.

With reference to the drawing, the bottle closure 2 has a body 4 which is secured at 6 to the inside of the neck 8 of a bottle for containing carbon dioxide.

A connector 10 is secured on top of the body 4 for connecting the bottle to a home carbonating apparatus with which the bottle is to be used for making carbonated drinks in the home. An outwardly directed annular flange 12 integral with the upper end of the body 4 is provided for receiving locking elements (not shown) for locking the closure 2 to the carbonating apparatus.

An axially displaceable valve element 14 is mounted inside a downwardly directed cylindrical barrel 16 of the connector 10 and is integral with a plunger 18 whose upper end is engageable by a valve actuating member (not shown) of the carbonating apparatus for pushing the valve member 14 downwardly against the action of a compression spring 20 to open the valve.

The compression spring 20 is disposed in a space 22 formed in the body 4 and, when the valve is closed, presses a sealing ring 24 firmly against a seat 26 of the connector 10 to provide a gas tight seal. The space 22 is connected to the interior of the bottle by an axial passage 28, whose lower end opens into a further space 30 provided in the body 4. As can be seen in the drawing, the axial passage 28 is disposed eccentrically with respect to the axis of the bottle and the body 4. A plug 32 is threaded into the space 30 and contains a passage 34 through which gas may pass from the interior of the bottle to the passage 28 for supply to the carbonating apparatus when the valve 14 is opened. An annular space 35 is provided above the plug 32 so that the passage 34 communicates with the passage 28 via the space 35 regardless of the angular position of the plug 32.

The plug 32 contains a further, central axial passage 36 whose upper end is closed by a "bursting" disc or membrane 38 which is tightly gripped between the upper surface of the plug 32 and an annular shoulder 40 of the body 4. The disc or membrane 38 is constructed so that it will burst in response to excess pressure in the bottle, for example due to the bottle being heated, and thus act as a safety device preventing bursting of the bottle. To permit this, the body 4 includes an axially extending chamber 42 across the lower, open end of which the disc 38 is disposed and a pair of oppositely directed radial passages 44 connecting the chamber 42 to atmosphere. The corner 46 between the chamber 42 and the shoulder 40 is radiussed so as to permit the disc 38 to balloon upwardly in response to high pressure and facilitate controlled bursting thereof.

The arrangement illustrated is particularly advantageous. Firstly, since the bursting disc 38 is located in a radial plane it requires a minimum of space to be accommodated. In particular, the axial length (vertical height) of the closure may be reduced compared to prior art arrangements in which the bursting disc is positioned in an axially extending plane at the outer periphery of the valve closure.

Secondly, by arranging that the path which the gas follows upon bursting of the bursting disc is quite separate from the path which the gas follows for supply to the carbonation apparatus, the excess pressure in the bottle is relieved direct to atmosphere without risk of damage. Thirdly, by providing escape passages 44 in opposition to each other, forces produced on the bottle by escaping gas are cancelled out thus eliminating risk of the bottle being displaced, possibly at high velocity, upon bursting of the disc.

Claims

CLAIMS:

1. A closure for a gas bottle for use with home carbonation apparatus comprising a body, a connector at one end of the body for attachment to the carbonation apparatus, a gas supply passage for connecting the interior of the bottle to the connector, a valve for controlling the supply of gas through the gas supply passage, the valve including an actuating member engageable by a valve operating plunger provided in the home carbonation apparatus, a gas escape passage in the body, and a membrane which normally closes the gas escape passage and which is burstable under excessive pressure, the gas escape passage being provided in the body separately from the gas supply passage so as to provide a connection from the interior of the bottle to the periphery of the body and thereby to atmosphere, and the burstable membrane being secured across the gas escape passage substantially in a radial plane.

2. Apparatus according to claim 1, wherein the gas escape passage comprises a first axially extending portion across which the burstable membrane is secured and a second -portion connecting the axially extending portion to the periphery of said body and thereby to atmosphere.

3. A closure according to claim 2, comprising a plurality of said second portions opening to atmosphere in such a way that reaction forces acting on the closure upon escape of gas under pressure through said gas escape passage substantially cancel.

4. A closure according to claim 3, wherein there are two said portions extending in opposite radial directions respectively.

5. A closure for a gas bottle for use with home carbonation apparatus comprising a body, a connector at one end of the body for attachment to the carbonation apparatus, a gas supply passage for connecting the interior of the bottle to the connector, a valve for controlling the supply of gas through the gas supply passage, the valve including an actuating member engageable by a valve operating plunger provided in the home carbonation apparatus, a gas escape passage in the body, and a membrane which normally closes the gas escape passage and which is burstable under excessive pressure, the gas escape passage being provided in the body separately from the gas supply passage,ysaid gas escape passage having an inner end for communication with the interior of the bottle and leading to the periphery of the body and thereby to atmosphere, and the burstable membrane being secured across the inner end of the gas supply passage.

6. A closure according to claims 1 to 5 including a plug secured in said body to clamp said membrane in its position.

7. A closure according to claim 6, wherein said plug is threaded into said body.

8. A closure according to claim 6 or 7, wherein said plug includes a first passage extending therethrough and communicating with said gas supply passage and a second passage extending therethrough for communication with said said gas escape passage.

9. A closure according to claim 8, wherein said plug defines an annular space communicating with said first passage and said gas supply passage whereby said first passage communicates with gas supply passage via said annular space regardless of the angular positon of the plug.

10. A closure according to any preceding claim, wherein the valve is located adjacent said connector.

11. A bottle closure substantially as herein described with reference to the accompanying drawing.