GB2342417A - A connector for use in supplying treatment chemicals to central heating systems - Google Patents

Abstract

A pipe-like connector comprises a spout portion 2, a parallel male thread portion 4, and a tapered male thread portion 6 connected to one another. The connector includes mounting means 7, eg for mounting to a treatment chemical container (10, fig 4), and may also include a hexagonally flattened section 5 which allows the connector to be lightened with a spanner. Preferably the connector is for use in supplying a central heating system with treatment chemicals. Preferably the connector wall at the join between the spout portion and the parallel thread portion is thinned 3 so that the two portions are detachable, eg by using a sharp knife, when it is desirable to use a filling loop (8, fig 4) and a dispensing gun. Alternatively the tapered thread portion may be screwed into the plug hole 16 of a radiator, and connected to yet another pipe-like connector via a hose 12.

Description

Connector This invention is concerned with a connector, and relates in particular to a multi-purpose, adaptable connector that can be used to make connections into the various parts of a central heating system.

A central heating system-specifically a domestic system using water as the heat transfer mediumcomprises a boiler (or other heating device) for heating the water, a number of radiators to which the hot water may be transferred (usually by being pumped, though some older systems still use convection and gravity transfer), and associated pipes appropriately connecting the boiler to the radiators and the radiators to each other, to form a closed circuit. In general the boilers used for this purpose have cast iron, or steel, sections within which the water is heated, the radiators are mild steel, and the pipes are either copper or a plastic.

Central heating systems of this kind suffer from a number of problems, of which important ones are corrosion of the materials-particularly any iron/steel parts-from which the system is made, the deposit of scale (which is most common in hard water areas, but can occur anywhere), and the formation of"sludge". All these can be dealt with satisfactorily by providing appropriate chemicals in the circulating"process" water; chemical treatment can remove commissioning residues, control sludge, remove scale, and inhibit corrosion. Furthermore, treatment chemicals can be used to inhibit microbiological growth, to control boiler noise, and to seal internal leaks. The problem is how to get the chemicals into the system, whether full or empty of water, in a clean, tidy, controllable manner.

Some central heating systems-and especially the older sort-have their own open-topped supply tank (usually up in the loft, adjacent the normal cold water tank). This is a feed-and-expansion tank; it is open to the circulating water (but being well above the system doesn't allow any to"escape"), and when that water is hot it can expand into the tank, and it is connected to the cold water mains supply (usually by a ball-cock valve) so that the system can be topped up if it loses water (by a leak or evaporation, say). At its lowest point, which is usually adjacent the boiler, such a system will normally have a valved drain spout, or drain-cock, allowing all the water in the system to be drained off or swilled through if necessary-for example, after commissioning to remove residues such as fluxes and general debris. Sometimes there is more than one such drain spout. A diagrammatic drawing of this open sort of system is shown in Figure 1 of the accompanying Drawings (which is described in more detail hereinafter).

A more modern variety of central heating system is the sealed, pressurised, system, where the open feedand-expansion tank up in the loft is replaced by a closed reservoir adjacent the boiler; the reservoir is sealingly divided into two parts by a flexible membrane, one part being connected to the system's pipework (and so being full of system water; this water is pumped into the system through a non-return valved filling loop when the system is first constructed and commissioned) and the other being filled with compressed gas (typically air or nitrogen) to pressurise the entire system. Such a sealed system will also normally have a valved drain spout. A diagrammatic drawing of this sealed sort of system is shown in Figure 2 of the accompanying Drawings (which also is described in more detail hereinafter).

As noted above, the problem with the use of treatment chemicals is how to get them from the container in which they are supplied-and such a container may range from a simple bottle to a tubular cartridge used in a dispensing gun-into the water in a clean, tidy, controllable manner. With an open system there are several ways. The simplest is to add the chemicals to the feed-and-expansion tank, from which the chemicals will, as the water expands and contracts into and out of the tank, eventually be drawn into the circulating water within the system. However, this will take some time-about six weeks or so for an average operational system-which is a significant drawback, since for most of that time the system proper has little of the chemicals actually circulating around it, and certainly not enough to provide the desired level of protection. Accordingly, it is preferred if possible to feed the chemicals into the system in some manner which causes the whole dose to be added immediately.

One such way is to pump the chemicals into the system via the (or a) drain spout-if the system is not first drained, then this pumping must of course be against any pressure inside the system itself. Another such way is to inject the chemicals via one or other of the system's several radiators. Almost all radiators have at each end near their top a hole-usually slightly tapered-into which there is placed either a bleed valve housing (through which any air trapped in that radiator can in use be bled off) or a blanking plug (which is which is usually a matter of convenience).

Once the radiator's valves have been turned off to prevent leakage, such a radiator blanking plug hole is one of the most preferred ways of accessing the system, and adding any treatment chemicals.

With a sealed system, too, there are several ways of adding the chemicals. Obviously, there can be used both the drain spout and the radiator blanking plug hole route, and in addition it is possible to pump the chemicals in through the filling loop (much as the system was originally filled with water).

Of course, what is needed in every case is some sort of connector that allows the container-bottle or tube, say-of the treatment chemical to be operatively attached to whatever system component-drain spout, filling loop or radiator hole-is to provide the entry route. And equally obviously it would be highly desirable were such a connector to be"universal"-that is to say, to fit, or to be easily adaptable to fit, the relevant component (those mentioned are all different sizes, shapes and types).

It is such a connector that the present invention proposes. More specifically, the invention proposes a multi-purpose pipe-like (or"through-bore") coupling, or connector, having a plurality of portions including ones forming a spout (a hose connector), a parallel male thread (for connection to, say, a filling loop input) and a tapered male thread (for, say, connection to a tapered radiator plug hole)-the relative positions of the threaded sections and connector are not especially important, though most preferably the spout not only extends from one end of the parallel thread portion at the other end of which is the tapered thread portion but is relatively easily detachable therefrom for when it is not required-together with means by which the whole can be mounted onto the relevant treatment chemical container.

In one aspect, therefore, the invention provides a pipe-like connector comprising, operatively connected one to another, a spout portion, a parallel male thread portion and a tapered male thread portion, together with means for mounting the whole to a container of the treatment chemical.

The invention provides a multi-purpose pipe-like (or"through-bore") connector having a plurality of portions. As will be evident, the idea is that one or other of these portions will allow the connector to be attached to any of the heating system components through which treatment chemicals could be transferred into the central heating system.

The connector has, first, a portion forming a spout by which it can be joined to a hose, the hose being drawn over the spout. This spout is conveniently around 3.5cm (13/sin) long and 1. 3cm (0. 5in) external diameter, and it has"barb"-like ridges to make it easy to insert into (and a good seal within), but a tight (interference) fit in and so less easy to pull out of, a standard 12mm hose pipe.

Second, the connector has a portion with a parallel male thread for connection to, say, a filling loop input. Such a thread is a 1/2in BSP thread (about 2cm [3/4 in] external diameter and with a pitch of 14 threads per inch, so making it a good fit to the standard variety of filling loop end fitting. The portion is conveniently about 1. 3cm (1/2 in) long.

Third, the connector has a portion with a tapered male thread for, say, connection to a tapered radiator plug hole (for historical reasons the threaded plug holes in radiators always seem to be very slightly tapered, being narrower at the inside end and wider at the outside end). The taper is very small: a 1/2in BSPT thread, that appears to be about 2cm (3/4 in) external diameter, with a pitch of 14 threads per inch, actually tapers by only 1 part in 16 (in diameter) from its outside to its inside end. The portion is conveniently about 1. 3cm (l/zin) long-though it might be longer if that were necessary to allow its attachment to a treatment chemical container, as discussed below.

As noted above, the relative positions of the threaded sections and connector are not especially important, though some arrangements might be rather inconvenient. Most preferably, however, the spout extends from one end of the parallel thread portion at the other end of which is the tapered thread portion (this ensures that in use the most amount of expensive treatment chemical is injected into the heating system and the least is left inside the connector). And in such a case, it is preferred that the spout be relatively easily detachable from the parallel thread portion for when its use is not required. Such ease of detachment can be achieved by thinning the connector wall at the join between the spout and the parallel thread portion, so that either the spout can simply be snapped off by the application of muscle power or it can with relative ease be cut off with a sharp knife.

Because the purpose of the two threaded portions is to enable the connector to be screw-attached to some component of the heating system it will be necessary to be able to turn-to screw-the connector relative to the component, and to do this with sufficient force to make a good, tight, leak-proof, seal. While it can obviously be gripped by hand, this may not be sufficient, and might even damage the connector.

Accordingly, it is preferred that the connector include an additional portion which is shaped to be like a nutto have flats on it-so that a spanner can be utilised to tighten up the connection being made. A standard spanner of the sort carried by plumbers is a 19mm (across the flats) spanner, so conveniently the nut portion is shaped to be that size.

The invention's connector includes means by which the whole can be mounted onto the relevant treatment chemical container. This mounting means could be of any convenient form, depending on what sort of container the connecter is to be attached to, and may be an integral part of the connector or may be separate therefrom. For example, many containers will have a spout, or nozzle, so one suitable means is simply to ensure that the internal bore of the connector, preferably within the tapered thread portion (so as to keep the connector as short as possible), matches the external dimensions of that nozzle. Some such container nozzles may themselves be externally threaded-the conventional cartridges used in dispensing guns (which are capable of generating pressures of around 5 bar, and so can easily overcome the internal pressure of the heating system) are usually provided with a threaded nozzle-so it is convenient to provide the bore with a matching internal thread. On a standard 310ml cartridge the nozzle is quite shortabout 1. 5cm (l/2in) long-while on a 385ml cartridge it is rather larger; to accommodate the larger sort it may be desirable to construct the tapered thread portion in two adjacent parts-two short parts adding to make one long part-the end one of which can be broken or cut off (like the spout) if not required. A similar, but slightly larger, removable internally-threaded extension could be utilised to allow the connector to fit directly onto the threaded male connection by which a filling loop normally is operatively attached to the system.

With a short (10cm [4in]) length of hose (to provide some flexibility) and a second connector, this would be a possible alternative to using the filling loop itself.

And if treatment chemical containers came with, say, a bayonet fitting, then clearly the mounting means would have a matching bayonet socket.

Sometimes, however, the treatment chemical container will just be a bottle, conveniently with some sort of valve to allow air in as the treatment chemical flows out, and in that case the mounting means is conveniently separate from the connector itself, and is a short (lOcm [4in]) length of hose together with a (screw) cap that fits the bottle and has its own spout projecting therefrom. In such a case, the connector's spout is a tight fit within the hose at one end, the cap's spout fits similarly within the other, and the cap is then attached to the bottle, which is then inverted to empty its contents through the hose and connector and so into and through whatever component the connector is joined to at its other end.

There may be occasions when it is desirable to employ more than one of the connectors of the invention at the same time. For example, when intending to pump treatment chemicals from a cartridge (loaded into a dispensing gun) into the heating system through a radiator plug hole it may be inconvenient to have the connector forming a rigid link between the radiator and the cartridge. In such a case, therefore, it is much preferred that a first connector be screwed into the plug hole, that a second connector be mounted onto the cartridge, and that the two then be operatively joined by a short length of flexible hose pipe.

The connector of the invention may be made of any suitable material strong enough to withstand the forces involved in its use and sufficiently resistant to the effect of the chemicals to be passed through it. One typical class of such materials is the polyalkylenes, especially one or other of the several polypropylenes (a connector can easily be made from these, which are thermoplastics, by conventional injection moulding techniques).

The multi-purpose connector, or adapter, of the invention can offer immediate central heating system treatment by entry via the filling-loop, the drain-cock spout or the radiator blanking plug hole, whether or not the system is full of process water. More specifically, the system can be emptied completely, and the treatment chemicals can be added thereto from a standard can (preferably with air-input valve) either into a radiator (blanking plug) hole or by way of the filling loop.

Alternatively, using its own valves a single radiator can be closed off/isolated from the rest of the system, fully or partially drained, and then treated with chemicals in the same way. And it is not possible, or desirable, to empty the system in whole or in part, then the chemicals can be pumped into the full system against its internal pressure (whether that of the pressure vessel in a sealed system or that of the static head hydraulic pressure in an open system) from a standard cartridge/dispensing gun combination. Such versatility enables water treatment chemicals to be introduced into all central heating systems, and the User is afforded the choice and flexibility to do this in the easiest way to his/her specific system.

An embodiment of the invention is now described, though by way of illustration only, with reference to the accompanying diagrammatic Drawings in which: Figures 1 & 2 show respectively the layouts of open (feed-tank-supplied) and closed (sealed) central heating systems; Figure 3 shows, as an axial section view, a connector of the invention; Figure 4 shows the use of the invention's connector via a filling-loop ; Figure 5 shows use via a drain-cock; Figure 6 shows use via a radiator blanking plug; and Figure 7 shows use from a bottle-like container of chemical.

Figure 1 depicts a house with one of the older, open (feed-tank-supplied) central heating systems, and shows the layout of the system, while Figure 2 shows the layout of the system in a house with one of the newer, closed (sealed) central heating systems.

Figure 1-which also depicts the ordinary cold and hot water systems as well (these are omitted from Figure 2)-shows how the boiler (21) feeds hot centralheating-system water to a"circle"of radiators (as 22) along pipework that includes a feed (23) from a small feed-and-expansion tank (24) in the loft. An expansion pipe (25) delivers excess water from the heating system circuit back to the tank 24. Such a system would normally have a drain-cock (not shown) adjacent the boiler 21, and possibly a number of other drain-cocks at other places in the circuit (including adjacent one or more radiator 22).

Figure 2 shows the layout of one of the newer, closed (sealed) central heating systems. Once the system is filled with water (from a filling loop-not shown-that connects into the system adjacent the boiler) it is sealed up (and has no connection into the house's water supply). The system is pressurised by air pumped into pressure vessel (31), which is divided into two parts by a flexible membrane (32) with the system water circuit on one side and air (33) under pressure on the other.

Figure 3 is an axial section through a connector (or adapter) of the invention. The connector comprises, integrally joined one to the next: a spout portion (2) for connection to a hose; a parallel male thread portion (4) by which the connector can be attached to, say, a heating system filling loop; a hexagonallyflatted section (5) enabling the connector to be tightened up with a spanner to make a water-tight seal; and a tapered male thread portion (6: the taper is shown vastly exaggerated, for effect)). The connector has a through bore (1), and so is pipe-like, and within the tapered threaded portion 6 there is an internal thread (7) for mounting the connector to some pumping device (not shown). The spout 2 and parallel thread portion 4 are joined by a recessed thin-wall section (3) at which the spout section can easily to be removed (cut of with a sharp knife, or simply snapped off) to "expose"the parallel male thread portion 4.

Figure 4 shows the use of the invention's connector via a filling-loop, with the connector suitably "configured"-by removing the spout-into a short form (9) for connection to a filling loop (8) of the type found in all sealed heating systems. The spout 2 has been removed with a sharp knife by cutting through thin-wall section 3 to allow the connector to be coupled to the filling loop 8 using the now-exposed parallel male thread 4. The internal thread 7 at the other end is then attached to a cartridge (10) of treatment chemical in a dispensing gun (not shown), and the chemical is then pumped in using the gun.

Figure 5 shows use via a drain-cock (11), with the connector"configured"appropriately. The connector is connected to the drain-cock 11 via a short flexible hose (12) attached into which the connector's spout 2 fits sealingly, and-as in Figure 4-the internal thread 7 is used to attach the connector to a treatment chemical cartridge 10.

Figure 6 shows use via a radiator blanking plug hole (16) in a radiator (14) after removal of the blanking plug (15) therefrom. The connector is screwed into the plug hole 16 using the tapered male thread 6.

A second connector is attached to a treatment chemical container 10 using its internal thread 7, and the pair of connects are coupled together via a short flexible hose 12 attached to each connector's hose connector spout 2.

Finally, Figure 7 shows the use of a connector of the invention to allow a standard bottle-like container of chemicals to be connected to a central heating system. For the most part the arrangement is much like that shown in Figure 6, with the hose-borne connector screwed into the radiator blanking plug hole 16 using the tapered male thread 6, but at the radiator-distant end the hose 12 is connected to a special fitting (41 : a spout and screw-cap combination) that can be attached to the mouth of a bottle or jerry can type of container (42) provided with a valved air inlet (43)

Claims (8)

1. Claims 1. A pipe-like connector comprising, operatively connected one to another, a spout portion, a parallel male thread portion and a tapered male thread portion, together with means for mounting the whole to a container of the treatment chemical.
2. 2. A connector as claimed in Claim 1, wherein the spout portion has"barb"-like ridges to make it easy to insert into, but a tight fit in, a standard hose pipe.
3. 3. A connector as claimed in either of the preceding Claims, wherein the spout portion extends from one end of the parallel thread portion at the other end of which is the tapered thread portion.
4. 4. A connector as claimed in Claim 3, wherein, so that the spout portion be relatively easily detachable from the parallel thread portion, the connector wall at the join between the two portions is thinned.
5. 5. A connector as claimed in any of the preceding Claims, wherein there is included an additional portion which is shaped, with flats, to be like a nut, so that a spanner can be utilised to tighten up the connection being made.
6. 6. A connector as claimed in any of the preceding Claims, wherein the means by which the whole can be mounted onto the relevant treatment chemical container is a thread within the internal bore of the connector's the tapered thread portion, which internal thread matches an external thread on a nozzle on the container.
7. 7. A connector as claimed in any of Claims 1-5, wherein, where the treatment chemical container is a bottle, the mounting means is separate from the connector itself, and is a length of hose together with a screw cap that fits the bottle and has its own spout projecting therefrom, the connector's spout being a tight fit within the hose at one end, the cap's spout fitting similarly within the other.
8. 8. A connector as claimed in any of the preceding Claims and substantially as described hereinbefore.