AU2021236428A1

AU2021236428A1 - Gas Appliance Isolation Valve

Info

Publication number: AU2021236428A1
Application number: AU2021236428A
Authority: AU
Inventors: Scott Michaels
Original assignee: Zetco Valves Pty Ltd
Current assignee: Zetco Valves Pty Ltd
Priority date: 2020-09-22
Filing date: 2021-09-20
Publication date: 2022-04-07

Abstract

A gas appliance isolation valve (40, 140, 240) is disclosed which takes the form of a housing (41), a handle (44) mounted on the housing to permit the valve to be placed in either a valve open or a valve shut position, a valve outlet (43) and a valve inlet (42). 5 The valve outlet has a male parallel thread, the valve inlet is a press seal pipe coupling and the housing includes a mounting means in the form of foot flanges (46) to permit the valve to be secured to a supporting surface such as a wall or floor. A method of installing a gas appliance to connect same to a gas supply pipe via the gas isolation valve is also disclosed. The method utilises an "easy hooker" style of 10 flexible hose (5) which terminates in a swivel nut connector (7). The method includes the steps of, in any order: (i) connecting the flexible hose to the male parallel thread of the valve outlet, and (ii) connecting the pipe coupling to the gas supply pipe. 5183BV-AU

Description

Gas Appliance Isolation Valve

Field of the Invention The present invention relates to isolation valves for gas appliances such as cookers or cooktops, stoves and wall mounted gas heaters (whether flued or unflued).

Background Art Gas has long been used in domestic and commercial premises as source of energy for cooking and heating. Because gas is invisible, explosive and poisonous many regulations specifically relating to gas are in force in Australian. Such regulations include Australia/New Zealand Standard AS/NZS 5601 and such standards are quite different from the standards and regulations governing water supply and reticulation such as AS/NZS 3500. For such reasons plumbers require an additional qualification in order to be qualified to act as gas fitters. It is also possible to qualify as a gas fitter without being a plumber.

While some items of hardware such as pipes and elbows are able to be used for both gas and water applications, in general many hardware items, and valves in particular, are differentiated according to whether they are intended for use with gas, or are intended for use with water. There are various structural and/or operational reasons for this.

For example, a major point of differentiation between gas and water valves is that valves for water are able to use jumper valves and ceramic disc quarter turn type valves which are unsuitable for control of gas flow. Because of this operational difference, an industry convention has arisen that valves for water have green or blue handles and valves for gas have yellow handles so as to provide a visual indication because a valve's interior construction is hidden by the valve housing.

Furthermore, some gas hardware items such as gas cylinders are provided with a left hand thread rather than a right-hand thread as a safety measure in order to deter people who are not gas fitters from assembling an installation including such left-hand thread devices.

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Similarly, most O-rings used in water valves are not suitable for gas valves and visa versa. Other areas of differentiation between gas and water valves include the pressure rating which is required to pass certification, different testing procedures for gas valves and water valves, and different requirements for the torque required to operate the valve handle for gas valves and water valves.

Still further, plumbers' sealing tape for sealing threaded water fittings is coloured white and is unsuitable for use with gas fittings since it is liable to deteriorate in contact with gas over time and therefore give rise to gas leaks. For this reason, gas fitters have a different type of sealing tape which is coloured yellow.

Traditionally gas cooking took place on a freestanding stove which included both an oven and gas burners. However, in recent years the number of freestanding stoves sold has declined. Furthermore, gas burners in the form of a gas cooker are now provided independently of any oven. This enables prospective purchasers to choose an electric oven, for example, in combination with a gas cooktop or cooker.

In particular, for gas cooktops AS/NZ 5601.1 Paragraph 6.6.3 specifies that it is necessary in commercial or industrial buildings and in residential apartment buildings to have an isolation valve adjacent the cooktop in order to permit the gas supply to be turned off in an emergency. The same standard requires only that such an isolation valve is optional for a single residential dwelling, however, it is clearly desirable for such dwellings. Furthermore, given the preponderance of apartments being built in Australian cities of recent years, from a commercial point of view such a gas isolation valve is a significant item of commerce. Similar considerations apply in relation to gas heaters.

Furthermore, such a gas isolation valve needs to be at a location adjacent the cooktop or heater, rather than the isolation valve being the main isolation valve for the premises. Usually such a main isolation valve is located adjacent the gas meter for the premises and therefore is normally some distance from the cooktop or heater. Since the appliance isolation valve is likely to be operated under emergency conditions, it is necessary (or desirable for single dwellings) for the appliance

5183BV-AU 2 isolation valve to be both visually apparent and physically accessible. In most instances items closely adjacent the cooker or heater such as bench tops, other appliances, and the like, means that the physical space available for such an appliance isolation valve is limited and the gas fitter installer of such an isolation valve almost always finds that the installation is cramped.

A gas appliance isolation valve also is useful during initial construction if various gas appliances such as a gas cooker, a gas room heater, a gas hot water system, and so on are supplied at different times. If each appliance isolation valve is installed before any appliances are delivered, the gas supply can be turned on with the isolation valve turned off before the various appliances are delivered. After each appliance is connected, the corresponding isolation valve can then be turned on.

Hitherto a conventional in-line gas valve with a threaded inlet and outlet has been used as the isolation valve for gas appliances. The outlet of such an in-line gas valve is connected to the gas appliance by a flexible hose known as an "easy hooker" (Trade Name) flexible hose. The inlet of the in-line gas valve is connected to the gas supply pipe providing gas to the appliance by means of conventional plumbing fittings. Usually such plumbing fittings involve the use of thread tape which requires some degree of skill on the part of the gas fitter lest there be too much tape, or too little tape, utilised.

When one looks at a catalogue of a supplier of plumbing fittings, one cannot help but be impressed, often to the point of being overwhelmed, by the number and variety of items available for sale. It seems that every conceivable size and shape of plumbing fitting and valve is available for selection by intending customers. However, it is not the case that such catalogues display every desired article since specialised applications can, and do, arise.

Genesis of the Invention The Genesis of the present invention is a desire to both fill such a product niche (and thereby expand the product range available to prospective purchasers to cater for specialised applications) and provide for an easier installation of such a gas appliance

5183BV-AU 3 isolation valve by the gas fitter. In particular, there is a desire to avoid the need to use thread tape in the appliance isolation valve installation.

Summary of the Invention In accordance with a first aspect of the present invention there is disclosed a gas appliance isolation valve comprising a housing, a handle mounted on said housing to permit said valve to be placed in either a valve open or a valve shut position, a valve outlet and a valve inlet, wherein said valve outlet comprises a male parallel thread, said valve inlet comprises a press seal pipe coupling, and said housing includes a mounting means to permit said valve to be secured to a supporting surface.

Preferably the valve is intended to isolate a gas supply to a gas appliance such as a gas cooker installed in a building. The gas supply takes the form of a copper pipe extending from a wall of the building and the gas cooker has a flexible "easy hooker" style connecting hose terminating in a conventional swivel nut and metal dome connector, the dome connector having a through passage leading to the hose.

In accordance with a second aspect of the present invention there is disclosed a method of installing a gas appliance to connect same to a gas supply pipe via a gas isolation valve as defined in the above paragraph, utilising an "easy hooker" style of flexible hose which terminates in a swivel nut, said method comprising the steps of; in any order: connecting said flexible hose to said male parallel thread of said valve outlet, and connecting said pipe coupling to said gas supply pipe.

According to another aspect of the present invention there is provided a gas appliance isolation valve installation for a gas cooktop or similar gas appliance to be supplied with gas via an "easy hooker" style of flexible hose which terminates in a swivel nut, the supply being from a gas supply pipe, wherein said installation comprises a gas appliance isolation valve as defined in the above paragraph having said swivel nut of said flexible hose connected to the outlet of said gas appliance isolation valve, and having the pipe coupling connected to said gas supply pipe whereby said installation does not utilise sealing tape.

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Brief Description of the Drawings A preferred embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings in which: Fig. 1 is a plan view illustrating the use of a conventional in-line gas valve as a cooker isolation valve and plumbing fittings to connect to the gas supply pipe, Fig. 2 is a perspective view of the gas appliance isolation valve of a first embodiment, Fig. 3 is a plan view of the gas appliance isolation valve of Fig. 2, Fig. 4 is a side elevation of the gas appliance isolation valve of Fig. 2 Fig. 5 is an outlet end view of the gas appliance isolation valve of Fig. 2, Fig. 6 is a perspective view of the gas appliance isolation valve of the second embodiment, Fig. 7 is a perspective view of the gas appliance isolation valve of the third embodiment, Fig. 8 is a side view of the gas appliance isolation valve of Fig. 7, and Fig. 9 is a perspective view of the gas appliance isolation valve of Fig. 7 being about to be connected to a gas supply pipe and an "easy hooker" flexible connection hose.

Detailed Description As seen in Fig. 1, a gas supply pipe 1 protrudes from a first wall 2. The gas supply pipe 1 is located adjacent a corner 3 or other surface of a building cupboard or equivalent kitchen enclosure, adjacent a gas cooker or similar gas appliance (not illustrated). The gas pipe 1 may be plumbed in during the construction of the building and is thus installed long before the installation (or re-installation) of the gas cooker. When the gas cooker is to be installed, a connection hose 5 termed an "easy hooker" has one end (not illustrated) connected to the cooker. The size of the gas inlet on the cooker is normally DN15mm (half inch) and this determines the size of the upstream components such as the connection hose 5, prior art gas isolation valve 6 and gas pipe 1.

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The connection hose 5 is formed from flexible material, such as an elastomer, which is covered with stainless steel braiding. Two identical fittings 7 are swaged to either end of the hose 5. Each fitting 7 comprises a loose nut with an interior female thread and a metal dome having a through passage which leads to the interior of the hose 5.

In the prior art arrangement illustrated in Fig. 1, the gas supply pipe 1 is connected to a first fitting 10 having a press seal inlet 11 and a male tapered thread outlet 12. Sealing tape is used to (hopefully) create a gas tight seal with a female threaded inlet 14 of the gas isolation valve 6. The gas isolation valve 6 has a handle 15 and a male tapered thread outlet 16 (which also requires sealing tape).

Next comes a gas bleed fitting 20 having a female threaded inlet 21 and a male parallel threaded outlet 22. A gas port 23 extends from the body of the gas bleed fitting 20 and is normally sealed by a screw or similar fastener having a Phillips head recess. The male tapered thread outlet 16 of the valve 6 is received in the female inlet 21 of the gas bleed fitting 20, however, this is somewhat obscured in Fig. 1 by a saddle 25 which is used to secure the entire arrangement to a planar surface such as a length of timber 4. The gas port 23 enables gas pressure measurements to be taken, particularly in relation to bottled gas supplies.

The male outlet 22 of the gas bleed fitting 20 has a parallel thread which could be directly secured to the loose nut 7. However, in this particular prior art arrangement the installing gas fitter has cut the gas supply pipe 1 short and therefore is obliged to use a second fitting 30 and third fitting 35 each of which has a press seal at one end and a thread at the other end. The fittings 30 and 35 are joined by a small length of copper pipe 31.

An important aspect of the plumbing fittings 10, 30 and 35 is that in order to make the necessary connections, the gas fitter needs to utilise conventional thread tape (not illustrated). Either too much, or too little, thread tape can result in gas leaks, so the use of thread tape at all is to be avoided, if possible.

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A gas appliance isolation valve 40 of the first embodiment is illustrated in Figs. 2-5. The gas appliance isolation valve 40 has a housing 41, a press seal inlet 42, a male parallel thread outlet 43 and a handle 44. The valve inlet 42 and valve outlet 43 are longitudinally aligned. In addition, the housing 41 has a pair of foot flanges 46 and a gas bleed port 47. The gas bleed port 47 is located substantially midway between the valve inlet 42 and valve outlet 43 and is substantially perpendicular to their longitudinal alignment.

In Fig. 6 a valve 140 of a second embodiment is illustrated. This valve is the same as the valve 40 of the first embodiment, except that the gas bleed port 47 is blanked off so as to leave a blind boss 147.

In Figs. 7 and 8 a valve 240 of a second embodiment is illustrated. This valve is the same as the valve 40 of the first embodiment except that the valve inlet 42 and valve outlet 43 instead of being longitudinally aligned, are substantially perpendicular to each other. This is a particular advantage in some mounting conditions which are particularly cramped.

As seen in Fig. 9, the gas isolation valve 240 (and each of the valves 40, 140) is able to be directly connected between the gas supply pipe 1 and the gas connection hose 5 without any intermediate fittings. This is possible because the gas supply pipe 1 is directly connected to the press seal inlet 42, and the loose nut 7 is directly connected to the threaded male outlet 43. As a consequence, there are a number of advantages achieved.

Firstly, no intermediate fittings (such as the first fitting 10 and gas bleed fitting 20, and possibly the second fitting 30 and third fitting 35) are required.

Secondly, no sealing tape is required.

Thirdly, there is a substantial saving in installation time for the gas fitter in utilising the gas appliance isolation valve 40, 140, 240 of the present invention.

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A fourth advantage lies in using a single gas certified device since this reduces the number gas fitter implemented joins and hence the number ofprospective leaks.

Fifthly, there is an enhanced convenience in working in a confined area because both the previous cumbersome prior art activity and the present installation are often carried out in the confined space of a cupboard, or thelike. The cumbersome prior art activity, as illustrated in Fig. 1, is to be contrasted with the situation using the valve 40, 140, 240 of Figs. 2-9. First of all, no sealing tape is required. The valve outlet 43 is connected directly to the connection hose 5 by means of the loose nut 7. The valve 40, 140, 240 is secured to the length of timber 4, or equivalent, by the foot flanges 46. This automatically positions the handle 44 with the desired orientation and physically secures the entire arrangement against vibration, for example. The installation of only one plumbing device, that is the valve 40, 140, 240, is required.

Finally, a glance at any plumbing supplier's catalogue, illustrating thousands of products, would seem to indicate that every possible combination of plumbing device has already been manufactured and is offered for sale. However, this is not the case, as no such catalogue product offers the numerous advantages of the present invention.

The foregoing describes only some embodiments of the present invention and modifications, obvious to those skilled in the gas fitting art, can be made thereto without departing from the scope of the present invention.

For example, it will be appreciated that the valve 140 is identical to the valve 40 save that the gas port 47 is blanked off in the valve 140 thereby making the valve 140 slightly cheaper to manufacture than the valve 40. The valve 140 is intended for use in those situations, such as gas reticulation mains supplied premises, where it is not necessary to test the supply pressure.

Similarly, the valve 240 will have applications in especially tight installation situations. Clearly, the valve 240 is also able to have its gas bleed port 47 blanked off so as to form the blind boss 147.

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In the drawings, the threaded outlet 43 is illustrated in conventional mechanical engineering fashion so that the actual threads are not illustrated. Also, in the drawings the same designation numbers are used in different embodiments for substantially the same features.

Furthermore, it should be understood that the present applicants have a very detailed knowledge of the Australian plumbing and gas fitting industries. Accordingly, the reference to prior art valves or fittings referred to herein, does not necessarily mean that other persons in the plumbing industry and gas fitting industry are aware of this prior art, nor does it mean that such prior art is sufficiently well known to constitute common general knowledge in the plumbing industry and gas fitting industry.

The term "comprising" (and its grammatical variations) as used herein is used in the inclusive sense of "including" or "having" and not in the exclusive sense of "consisting only of'.

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Claims

CLAIMS 1. A gas appliance isolation valve comprising a housing a handle mounted on said housing to permit said valve to be placed in either a valve open or a valve shut position, a valve outlet and a valve inlet, wherein said valve outlet comprises a male parallel thread, said valve inlet comprises a press seal pipe coupling and said housing includes a mounting means to permit said valve to be secured to a supporting surface.
2. The valve as claimed in claim 1 wherein said valve inlet and valve outlet are longitudinally aligned.
3. The valve as claimed in claim 1 wherein said valve inlet and valve outlet are substantially perpendicular.
4. The valve as claimed in any one of claims 1 - 3 wherein said housing further includes a gas bleed port.
5. The valve as claimed in claim 4 wherein valve inlet and valve outlet are longitudinally aligned, and said gas bleed port is substantially perpendicular to said longitudinal alignment.
6. The valve as claimed in claim 4 wherein said valve inlet, said valve outlet and said gas bleed port are substantially mutually perpendicular.
7. The valve as claimed in any one of claims 4-6 wherein said gas bleed port is located approximately equidistant between said valve inlet and said valve outlet.
8. The valve as claimed in any one of claims 1 - 7 wherein said mounting means comprises a pair of oppositely directed foot flanges.

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9. The valve as claimed in any one of claims 1 - 8 wherein said valve inlet and outlet each have the same size.
10. The valve as claimed in any one of claims 1 - 8 wherein said outlet size is DN15 (half inch) and said inlet size is DN15 (half inch) or DN20 (three quarters of an inch).
11. The valve as claimed in any one of claims 1- 10 and certified under Australian Standard AS4617 for gas appliances.
12. A method of installing a gas appliance to connect same to a gas supply pipe via a gas appliance isolation valve as claimed in any one of claims 1-11, utilising an "easy hooker" style of flexible hose which terminates in a swivel nut, said method comprising the steps of, in any order: connecting said flexible hose to said male parallel thread of said valve outlet, and connecting said pipe coupling to said gas supply pipe.
13. The method claimed in claim 12 and carried out without the use of sealing tape.
14. A gas appliance isolation valve installation for a gas cooktop or similar gas appliance to be supplied with gas via an "easy hooker" style of flexible hose which terminates in a swivel nut, the supply being from a gas supply pipe, wherein said installation comprises a gas appliance isolation valve as claimed in any one of claims 1-11 having said swivel nut of said flexible hose connected to the outlet of said gas appliance isolation valve, and having the pipe coupling connected to said gas supply pipe whereby said installation does not utilise sealing tape.
15. The gas appliance isolation valve installation as claimed in claim 14 wherein said gas supply pipe is located within a cupboard or equivalent kitchen

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16. The invention as claimed in any one of claims 1 - 15 wherein said gas appliance is selected from the class consisting of gas cookers, gas cooktops, gas stoves and gas room heaters.

Dated this 9 th day of September 2021

Zetco Valves Pty Ltd

By FRASER OLD & SOHN Patent Attorneys for the Applicant

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