WO2020084303A1

WO2020084303A1 - Improved pressurised junction box manifold

Info

Publication number: WO2020084303A1
Application number: PCT/GB2019/053018
Authority: WO
Inventors: Graham Hawthorne; John Hawthorne
Original assignee: Kinetic Machine Tool Service & Repair Ltd
Priority date: 2018-10-23
Filing date: 2019-10-23
Publication date: 2020-04-30
Also published as: GB201817247D0; EP3871303A1

Abstract

There is herein described an improved junction box manifold device. More particularly, there is described a pressurised split junction box manifold for use in installing a new cable or duct tubes into an existing occupied sub-duct that is located underground.

Description

IMPROVED PRESSURISED JUNCTION BOX MANIFOLD

FIELD OF THE INVENTION

The present invention relates to an improved junction box manifold device. More particularly, the present invention relates to an improved version of a pressurised split junction box manifold for use in installing a new cable or duct tubes into an existing occupied sub-duct that is located underground.

BACKGROUND OF THE INVENTION

This invention is an improvement of a published GB application ‘GB1619438.3 Pressurised junction box manifold’. Junction box manifolds according to the previous application have been an improvement over the prior art.

Cables are normally installed by using cable blowing equipment and machinery at ground level which allows the user to push cables into an underground subduct. The subduct is located within an inspection pit/manhole. The cables are installed by connecting a cable blowing machine directly to the subduct, thereby facilitating the installation of a single cable into the preinstalled duct. The pressurised junction box manifold facilitates additional cables to be installed into the original pre-existing occupied underground subduct within the confines of a small inspection pit/manhole.

Potential disadvantages of the prior art and the previous application are that the devices are relatively large and heavy, which makes handling and operating within a confined space difficult. Workers must manipulate the device into position at their foot level whilst standing in the hole and leaning over the top of the device, thus restricting their movement, whilst potentially not being able to bend over in a correct manner, and thus potentially injuring their backs. The amount of time spent bending over manipulating and assembling the product should therefore be thus minimised.

Further improvements to the previous application can also be made to minimise workers’ time spent stooping over the device whilst working in the manhole/installation pit by reducing the number of tasks they must carry out, and the difficulty of them. As highlighted in the previous application, the manholes/installation pits which the junction box manifolds are situated in may contain dirt and water. The devices may be situated in these muddy puddles, and so a good mechanical seal must be made to ensure water/dirt does not enter the device. Reducing the number of sealing surfaces will reduce the likelihood of dirt ingress.

When inserting the cable from the inlet to the outlet before it is blown, the cable can often be stiff and hard to bend. This means the user must bend the cable manually into the outlet, which can be strenuous and inconvenient, especially at the bottom of a hole. This task may also increase the time spent stooping over in the narrow hole. For example, the cable may have to be manipulated to bend from the ground level down to the junction box, where the junction box may be 1 .5 meters below the ground level and situated in a narrow hole. Ease of cable insertion is therefore desirable.

It is an object of at least one aspect of the present invention to obviate or mitigate at least one or more of the aforementioned problems.

Another object of the present invention is to provide an improved pressurised split junction box manifold for use in installing a new cable/cables or duct tubes into an existing occupied sub-duct that has no mechanical fixings and does not use threaded fasteners.

Another object of the present invention is to provide a pressurised split junction box manifold where the manifold has only one end cap and comprises an internal conical shaped guide for the cables to follow from inlet to outlet.

Another object of the present invention is to provide a pressurised split junction box manifold wherein the manifold is smaller and lighter than examples in the prior art.

SUMMARY OF THE INVENTION

According to a first aspect of the present invention there is provided a junction box manifold device capable of being used to overblow cables into pre-existing ducts and cables using a pressurised air source, the junction box manifold device may comprise: an upper and lower main section which are inter-lockable onto one another;

the junction box comprises a single end cap for the lower main section wherein the end cap interlocks onto the lower main section;

the junction box comprises a single end cap for the upper main section wherein the end cap interlocks onto the upper main section;

the upper and lower sections along with the end cap combine to form an air tight manifold chamber which can be pressurised;

an air inlet through which pressurised air from a pressurised air source can be fed into the air tight manifold chamber;

wherein the air tight manifold chamber comprises an internal surface which narrows from at least one of or a plurality of cable inlets to the cable outlet, capable of guiding the at least one cable to the cable outlet;

wherein at least one cable or cables are capable of being fed through from an inlet end to an outlet end of the junction box manifold device by high pressure air being blown into and out of the air tight manifold chamber.

The internal surface may be conically shaped, reducing in diameter from the cable inlets to the cable outlet. The internal surface may not be conically shaped but may be any shape which is capable of tapering in a convergent manner from the cable inlets to the cable outlet. The taper angle may be between around 5 degrees to about 45 degrees; or about 10 to about 30 degrees. The taper angle should allow the cables to be easily inserted into the cable outlet.

The lower main section may comprise at least one or a series of ports which interact with corresponding ports in the upper main section to form entry and exit ports for cables. In use, cables may extend from the lower main section to the upper main section.

In the lower main section there may be a protruding circumferential end edge and a circumferential receiving recess at one end only; and

in the upper main section there may be a protruding circumferential edge at one end with a corresponding circumferential receiving recess;

wherein the upper and lower sections interlock with the circumferential edges and circumferential receiving recesses interlocking. Connected to one end of the main lower section there may be a lower half end section wherein the lower half end section comprises at least one protruding circumferential edge and a circumferential recess and the protruding circumferential edge interlocks with the recess in the lower main section and forms a locking profile.

The lower half end section may also comprise a port within which there is located a coupling device, which may be a clamping collet and wherein the coupling device is capable of being interchanged for other coupling devices which can be used to clamp a range of various diameters of outlet ducting and pipework to be connected to the manifold housing. The port may be capable of housing more than one cable or outlet ducting.

One end of the main upper section may be an upper half end wherein the upper half end comprises a port within which there is located an internal clamping collet and wherein the clamping collet is capable of being interchanged for other split clamping collets which can be used to clamp a range of various diameters of outlet ducting and pipework to be connected to the manifold housing.

A mini duct and fibre optic feed line tubing may be capable of being fed into an exit port which is used as a primary liner and guide tube on an inlet and feed side of the manifold.

An interchangeable lipped seal such as a rubber lipped oil seal may also be capable of being used in one of the ports to function as a seal. The seal may be made of any other suitable sealing material. The seal may prevent debris and water from entering into the manifold.

The lower main end section may also comprise a pressure relief valve (PRV) which is used as a safety device to prevent over pressurization of the manifold assembly.

The upper half main end section may also comprise a quick release air inlet connection positioned opposite the outlets which is the air inlet point to pressurize the device and the main manifold body. Inlet and outlet ports formed by interlocking the different parts together may therefore be used for clamping around a variety of diameter sizes of outlet ducting and pipework. The ports may also house a plurality of outlet ducts and pipework.

The junction box of the present invention may therefore be used to install cable ducts and fibre optic cable using a compressed air source to in effect blow the new cable along and through an old cable. The cables may be used by phone companies, fibre optic cables providing internet usage and for any other form of electronic, communication or power supply cable.

The junction box manifold device may comprise a main lower section and an upper main section. The lower section may comprise a chamber and the upper main section may comprise a further chamber. The two chambers may combine together to form the main manifold body for the junction box manifold device of the present invention which is capable of being pressurised.

The lower main section may comprise a series of ports e.g. two main ports at one end and a single port at the opposite end. These ports may interact with corresponding ports in the upper main section e.g. two ports at one end and a single port at the other side, wherein the two ports feed cables into the corresponding single port in the other end.

Also, in the lower main section there may be a protruding circumferential end edge a circumferential receiving recess at one end. At the opposite end of the main lower part there may be a further protruding circumferential edge and a circumferential receiving recess.

There may also be inserted a mini duct and fibre optic feed line tubing into an exit port which is used as a primary liner and guide tube on the inlet and feed side of the manifold.

An interchangeable lipped seal such as a rubber lipped oil seal may also be used in one of the ports. For different applications, a different rubber lipped oil seal may be used dependent on the size of tubing and mini duct that they have to seal. The outside diameters are always the same and they seal on the internal profile of the taper locking end caps.

It should be noted that any form of interlocking mechanism may be used for the different component parts that does not rely on threaded screws and mechanical fastenings. This is to improve the seal formed, and to enable faster assembly of the apparatus.

The upper main section may also comprise a quick release air inlet connection which is the air inlet point to pressurize the device and the main manifold body.

The ports formed by interlocking the different parts together may therefore be used for clamping around a variety of diameter sizes of outlet ducting and pipework.

Moreover, using interchangeable split collets in the ports formed by interlocking the different parts together will allow a range of various diameters of ducting to be tightly held. The present invention device is therefore highly adaptable for a range of different diameter of ducts/tubing and therefore allows various sizes of cables to be installed.

According to another aspect of the present invention, there is also herein provided a method for inserting at least one cable into a junction box manifold device according to a previous aspect of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which:

Figure 1 is a view of a junction box manifold according to the present invention, showing some additional tools and fixings; Figure 2 is a view of the junction box manifold shown in Figure 1 in an open configuration, without the additional tools and fixings;

Figure 3 is a view of the junction box manifold shown in Figure 1 in an open configuration, including additional tools and fixings; and

Figure 4 is an end view of the junction box manifold shown in Figure 2.

DETAILED DESCRIPTION

A detailed description will be given of the present invention.

Figure 1 is a view of an embodiment of the present invention in a closed position, shown from above, generally designated (1). The upper (2) and lower (3) main bodies are shown in the assembled position with additional tools and fixings. The upper main body (2) can be seen to incorporate the pressure gauge (24), and the chain tensioning bracket location dowel pins on the inlet (21) and outlet (22) end. As described in the previous application, the clamping chains (15) are wrapped around the device to seal and secure the upper and lower halves together by using the bolts (14,16) and nuts (13,17). The torque wrench (20) used in conjunction with the adaptor (19) is for tightening the nuts (14,16).

Figure 2 is a view of the junction box manifold (1) in the open configuration, showing the lower main body (3). The existing outer pipe (4) can be seen on the outlet side of the device, contained by the split ring seal (6) and the self-adjusting collet (5). The existing cable (34) can be seen to run from the inlet (21) through to the outlet (22). The new cable (32) to be blown in can be seen traversing the inlet side through the self- adjusting collet (7) and into the outlet through the exiting pipe (4).

The inside shape of the device is conical (30), to guide the cables from the inlet

(21) to the outlet (22). This makes it much easier for the user to push cables into the outlet

(22), as the cables can often be stiff and difficult to manipulate. Further to this, the shape also provides a more targeted and direct flow path for the compressed air entering the outlet duct. The shorter length of the device makes it easier to handle and position down a hole or in a tight/confined space, however it makes the insertion of cables from the inlet (21) to outlet (22) more difficult due to the decreased bend radius they must follow. The conical shape of the interior of the device helps with this issue. The shape of the interior may not necessarily be conical but may be any other funnel shape to direct the cables from the inlet (21) to the outlet (22). A blanking plug (9) is shown blocking one of the available ports (38) on the end cap (36). If the blanking plug (9) is removed, more cables can be inserted through the existing duct (4).

Another feature which is novel over the prior art is the use of a single end cap (36), thus reducing the number of sealing surfaces. The other end cap from the previous application has been incorporated into the main body of the device, allowing the device to be shorter and thus lighter, whilst improving airtightness. It will also be less likely for debris and dirt to obscure the sealing surfaces, since there are fewer surfaces to keep clean. Since the device (1) has fewer components, the user will spend less time assembling the device whilst undertaking an installation down the hole. This, in combination with the fact that the device (1) is lighter and smaller, will reduce the effort required by the user to install the device (1) and new cables. There will also be a reduction in the likelihood of injury to the user’s back as there is less mass to manoeuvre around at low level whilst in the narrow hole.

Figure 3 is a similar view to Figure 1 , with the device (1) in an open configuration. The lower main body (3) is shown with cables installed. The chain tensioning bracket (12) is shown with the lifting eye bolt (18) more clearly than in Figure 1 . The chains (15) and bracket (12) are used in conjunction to clamp the assembly together, creating an airtight seal, without using mechanical tools on the device itself. Figure 3 further shows the ports (38) located in the end cap (36).

Figure 4 is an end view of the device as shown in Figure 2, showing the inlet side with end cap (36) and a pressure relief valve (PRV) (11). The PRV is used as a safety device to prevent over pressurization of the manifold assembly. The position of the PRV ensures the excess air cannot be directed towards the user.

The cables may be used by phone companies, fibre optic cables providing internet usage and for any other form of electronic, communication or power supply cable. The pressure gauge and sampling port which the gauge is screwed into can be used by the user to ensure over pressurisation of the device does not happen. The sampling port pressure gauge can also be interchanged with a Bluetooth (RTM) pressure and temperature transducer that can be screwed into the sampling port. This transducer may use smart technology to send temperature and pressure data to the user’s smartphone or tablet.

It is a requirement for the lower section (3) and the upper section (2) to form an airtight seal as they are intended to form a pressurized chamber into which one end of an existing occupied sub-duct can be attached.

Once again, the protruding edges and recesses (40) may therefore interlock to form a secure airtight seal that does not rely on threaded screws and mechanical fastenings.

An advantage of the present invention is that although two inlet ports (38) are shown such as in Figures 2 and 3 any of these ports (38) may be blocked such as using a sealing blanking plug (9). A sealing blanking plug (9) may be used to isolate and blank off one of the feed ports (38) dependent upon process requirements.

The present invention may have a number of applications. For example, the mechanical taper locking seal and pipe clamping arrangement of the present invention can also be used for use in repairing or breaking into and branching off from severed or damaged mains water and gas lines. The present invention provides the advantage that there would be no need to typically weld a bolted flange assembly in the case of metal water pipes in position to join and seal both ends of the pipe. In the case of gas pipes it would remove the need to fuse the joints of the plastic pipes together using a heat fusion and sealing method.

The junction box manifold device may be rated at about 4 times the SWP of about 10 Bar which effectively means that it will be good to maintain an airtight seal at pressures up to 40 BAR -580 PSI. Through the use of the junction box manifold device according to the present invention and the interlocking mechanical arrangement there would be no need to weld flanges in position or to have the pipe cut to length to accommodate the space that would normally be taken up by the installation of a typical mechanical flange and seal arrangement. It would also reduce the time taken to assemble/join and repair or branch off from the pipes as there would not be numerous and often inaccessible bolts that require to be torqued up in order to obtain a good seal.

It will be clear to those of skill in the art, that the above described embodiments of the present invention are merely exemplary, and that various modifications and improvements thereto may be made without departing from the scope of the present invention. For example, any type of interlocking mechanical arrangement may be used to interconnect the different mechanical parts.

Claims

1. A junction box manifold device capable of being used to overblow cables into pre existing ducts and cables using a pressurised air source, the junction box manifold device comprising:

an upper and lower main section which are inter-lockable onto one another;

the junction box comprising a single end cap for the lower main section wherein the end cap interlocks onto the lower main section;

the junction box comprising a single end cap for the upper main section wherein the end cap interlocks onto the upper main section;

the upper and lower sections along with the end caps combine to form an air tight manifold chamber which can be pressurised;

wherein the air tight manifold chamber comprises an internal surface which narrows from at least one or a plurality of cable inlets to at least one cable outlet, capable of guiding at least one cable to the cable outlet;

wherein the at least one cable is capable of being fed through from an inlet end to an outlet end of the junction box manifold device by high pressure air being blown into and out of the air tight manifold chamber.

2. A junction box manifold device according to claim 1 , wherein the internal surface is conically shaped, reducing in diameter from the cable inlets to the cable outlet.

3. A junction box manifold device according to any preceding claim, wherein the lower main section may comprise at least one or a series of ports which interact with corresponding ports in the upper main section to form entry and exit ports for the at least one or plurality of cables.

4. A junction box manifold device according to any preceding claim, wherein

in the lower main section there is a protruding circumferential end edge and a circumferential receiving recess at one end only; and

in the upper main section there is a protruding circumferential edge at one end with a corresponding circumferential receiving recess; wherein the upper and lower sections interlock with the circumferential edges and circumferential receiving recesses interlocking.

5. A junction box manifold device according to any preceding claim, wherein connected to one end of the main lower section there is a lower half end section wherein the lower half end section comprises a protruding circumferential edge and a circumferential recess and the protruding circumferential edge interlocks with the recess in the lower main section and forms a locking profile.

6. A junction box manifold device according to claim 4, wherein the lower half end section also comprises a port within which there is located a clamping device, which may be a clamping collet, and wherein the clamping device is capable of being interchanged for other split clamping devices which can be used to clamp a range of various diameters of outlet ducting and pipework to be connected to the manifold housing.

7. A junction box manifold device according to any preceding claim, wherein one end of the main upper section is an upper half end wherein the upper half end comprises a port within which there is located an internal clamping device, which may be a clamping collet, and wherein the clamping device is capable of being interchanged for other clamping devices which can be used to clamp a range of various diameters of outlet ducting and pipework to be connected to the manifold housing.

8. A junction box manifold device according to any preceding claim, wherein a mini duct and fibre optic feed line tubing is capable of being fed into an exit port which is used as a primary liner and guide tube on an inlet and feed side of the manifold.

9. A junction box manifold device according to any preceding claim, wherein an interchangeable seal, such as a rubber lipped oil seal, is also capable of being used in one of the ports to function as a seal.

10. A junction box manifold device according to any preceding claim, wherein the lower main end section also comprises a pressure relief valve (PRV) which is used as a safety device to prevent over pressurization of the manifold assembly.

1 1 . A junction box manifold device according to any preceding claim, wherein the upper half main end section also comprises a quick release air inlet connection positioned opposite the outlets which is the air inlet point to pressurize the device and the main manifold body.

12. A junction box manifold device according to any preceding claim, wherein inlet and outlet ports formed by interlocking the different parts together may therefore be used for clamping around a variety of diameter sizes of outlet ducting and pipework.