WO1991010274A1

WO1991010274A1 - A cabling system and cabling junction box therefor

Info

Publication number: WO1991010274A1
Application number: PCT/AU1991/000003
Authority: WO
Inventors: Leo Tapani Kauhanen
Original assignee: Leo Tapani Kauhanen
Priority date: 1990-01-02
Filing date: 1991-01-02
Publication date: 1991-07-11

Abstract

A cabling system (9) and cabling junction box (10) therefor is disclosed. The cabling system (9) includes a backbone cable (34) having a coupling (32) attachable to an electrical interface (46) removably locatable in the cabling junction box (10). The backbone cable (34) is housed in a cabling duct (100) and transceiver cables (92) are routed from the interface 46 to a computer terminal (90) or the like. The cabling system (9) can be installed and the backbone cable (34) formed without installing the interfaces (46). The interfaces (46) can be installed into the cabling junction boxes (10) when required. The cabling system (9) and the cabling junction box (10) are particularly for use in LANs to enable coupling of computer terminals (90) and the like to the backbone cable (34) without affecting the integrity of the backbone cable (34). A combination of the cabling junction box (10) and the interface (46) alone are also claimed.

Description

I

TITLE A CABLING SYSTEM AND CABLING JUNCTION BOX THEREFOR

DESCRIPTION

The present invention relates to a cabling system and cabling junction box therefor, particularly for use in Local Area Networks (LANs) , although it is to be understood that it is of general applicability.

FIELD OF THE INVENTION

Generally, communication systems for computer installations rely upon a backbone cable connected to transceivers located in or attached to computer terminals. The backbone cable is generally routed in a cabling duct but must be routed out of the duct to each computer terminal and then back into the duct. Breaks are made in the backbone cable and each transceiver is serially connected in the respective breaks. The transceivers are sometimes placed upon the floor or adjacent the computer terminals and standard telecommunications cables, typicallyhaving D-type connections, are used to connect the transceivers to the computer terminals. A disadvantage of such arrangements is that the transceivers are relatively cumbersome and are not easily stored out of the way. Also, connection and disconnection of the cable from the transceivers to the computer terminals is not easily performed since some of the backbone cable must be pulled out of the cabling duct to reach the computer terminals. This sometimes requires lengthening of the backbone cable which necessitates disruption of the LAN whilst the lengthening is carried out. Further, there is a risk of accidental or mistaken interruption of the backbone cable by disconnection of the wrong coupling from the transceivers. This has the effect of crashing the entire LANs operating of the backbone cable. Such prior art systems have further disadvantages since the exposure of the backbone cable can lead to it becoming damaged by crushing, by furniture or from being walked on. SUMMARY OF THE INVENTION

It is thus desirable to create a cabling system which includes cabling junction boxes distributed along the backbone cable at locations where computer terminals are to be connected

5 in. A T connector is provided in each cabling junction box.

Each T connector continues the backbone cable and allows for connection to a transceiver. The transceiver is removably locatable in the cabling junction box so that the transceiver need be installed only when a computer is to be connected into

10 the backbone cable. The transceiver then receives and transmits data over the backbone cable whilst being connected to the computer by a single transceiver cable. The transceiver cable com .s into the transceiver via an aperture in the cabling ju.ocion box.

15 The use of the cabling junction box obviates the need to expose the backbone cable and makes the backbone cable more secure from accidental interruptions since the T connector is enclosed within the cabling junction box. Also, the cabling junction box provides a protective housing for the transceiver.

20 Further, once the transceiver is installed, a computer can be connected and disconnected from the backbone cable (by connection and disconnection of the transceiver cable to and from the transceiver) without use of the T connector. Thus, accidental interruption of the backbone cable is virtually

25 eliminated.

Therefore, the present invention provides an improved cabling system and junction box therefor which substantially reduces the likelihood of accidental interruption of electrical signe^' at a junction during disconnection from or connection 30 to the cabli:.^ system. According to one aspect of the present invention there is provided a cabling junction box comprising: a base part having a coupling for electrically connecting two electrical cables at a junction and being 35 adapted to house an electrical interface for connection to the junction; and, a top part removably attached to the base part, whereby, in use, the cabling junction box can facilitate connection to and disconnection from the junction without disruption of electrical signals through the junction. According to a second aspect of the present invention there is provided a cabling junction box and an electrical interface, the cabling junction box comprising a base part having a coupling for electrically connecting two electrical cables at a junction and a top part removably attached to the base part, the interface processing electrical signals between the two electrical cables and a further cable whereby in use, the cabling junction box can facilitate connection to and disconnection from the junction without disruption of electrical signals through the junction. According to a third aspect of the present invention there is provided a cabling system comprising a backbone cable formed from a plurality of electrical cables, connected together at a plurality of junctions, a plurality of cabling junction boxes one located at each said junction, each cabling junction box comprising a base part having a coupling for electrically connecting two electrical cables at a junction and a top part removably attached to the base part, the interface processing electrical signals between the two electrical cables and a further cable whereby in use, the cabling junction box can facilitate connection to and disconnection from the junction without disruption of electrical signals through the junction.

A rding to a fourth aspect of the present invention there is pr<_ _ded an interface for use with a cabling junction box comprising a base part having a coupling for electrically connecting two electrical cables at a junction and being adapted to house an electrical interface for connection to the junction and a top part removably attached to the base part, the interface comprising a box dimensioned for location in and removal from the cabling junction box, a connector located for connection to the junction and a further connector for connection to a further cable whereby, in use, the interface box allows connection to and disconnection from said junction without disruption of electrical signals through the junction.

In the context of the present invention, the term "object" is intended to include any stationary object, such as, for example, an electrical cabling duct, or a wall or the like. It is also envisaged that the object could include a work station, a desk, a book case, a shelf or the like.

Typically, the aperture for access of the further cable overlies the connector in the interface box. The present invention will now be described with particular reference to LANs and interfaces being transceivers conforming to the IEEE 802.3 standard for Ethernet LANs for communication between computer terminals, although it is to be understood that it is of general applicability.

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred embodiment, being an example only, of the present invention will now be described with reference to the accompanying drawings, in which:-

Figure 1 is a view of a cabling system, showing two computer terminals connected via transceiver cables to a backbone cable via a transceiver located in a cabling junction box;

Figure 2 is a plan view of a base part of the cabling junction box of Figure 1, shown containing a BNC T connector and the transceiver, the BNC T connector coupling the backbone cable to the transceiver;

Figure 3A is a perspective view, seen from above, of the cabling junction box including the base part, a top part and two inserts; Figure 3B is a perspective view, seen from above, of one of the inserts of Figure 3A;

Figure 4 is a further plan view of the base part of Figure 2, shown with the BNC T connector and the transceiver removed for clarity; Figure 5 is a perspective view, seen from below of the top part of the cabling junction box of Figure 3A;

Figure 6 is a perspective view, seen from above, of the transceiver of Figure 1;

Figure 7A is a circuit diagram of a transceiver circuit of the transceiver for the cabling system of Figure 1; and,

Figure 7B is a pin configuration for an RJ45 connector for the transceiver of Figure 7A.

DESCRIPTION OF THE INVENTION

In Figure 1 there is shown a cabling system 9 comprising a cabling junction box 10, a backbone cable 34, an interface means in the form of a transceiver 46, two computer terminals 90, two transceiver cables 92, and a cabling duct 100. Referring to Figures 2 to 5, the cabling junction box

10 comprises a base part 12, a top part 14 and two inserts 15. The base part 12 typically comprises four rectangular slots 16, two in each side wall 17 and 18, the slots receiving four hooks 19 in the top part 14 for removably attaching the top part 14 to the base part 12. The base part 12 also includes mounting means in the form of a plurality of apertures 24 disposed about the base part 12 so as to allow mounting thereof onto an object, such as, for example, the cabling duct 100, by bolts or screws or the like. The base part 12 also comprises two apertures 26 each sized to receive a cable 28 typically terminated by a male BNC connector 30. The male BNC connectors 30 are coupled together by a BNC T connector 32 whereby a plurality of the cables so connected for a backbone cable 34 of a LAN. As shown in Figure 4, the base part 12 also comprises two ledges 36 each located adjacent the apertures 26 so as to provide a support for either or both of the cables 28 and the BNC T connector 32. The ledges 36 are typically spaced apart so as to provide an opening 38 through which a male part 40 of the BNC T connector 32 may protrude (see Figure 2) . The ledges 36 together with the side wall 18 and end wall 42 of the base part 12 define a region 44 dimensioned to receive the transceiver 46 (see Figure 6) . In the present embodiment, the interface means is a transceiver interface of the kind such as conforming to the IEEE 802.3 standard for Ethernet LAN.

It is important, in the context of the present invention, that the transceiver 46 be locatable in and removable from the cabling junction box 10 as a separate unit. That is, the cabling junction box is capable of performing it's function with regard to the backbone cable 34 independent of the presence of absence of the transceiver 46.

The base part 12 of the cable junction box 10 also conveniently comprises two raise ribs 50 spaced apart and traversing the region 44 so as to displace the transceiver 46 from the base part 12 and thereby to provide a clearance to the plurality of apertures 42 so that fixing means, such as bolts or screws, fitted through the aperture 24, are less likely to foul with the transceiver 46. The base part 12 further conveniently comprises indents 52 positioned to receive conduit ducting or the like. In the event that conduits are to be received, the material of the walls 17 or 42 covering the indents 52 is conveniently removed in a known manner.

The base part 12 also has two cut-outs 54, one formed in each end wall 42. The end walls 42 have "V" shaped grooves 56 running about the cut-outs 54.

The top part 14 has a perimeter 58 of complementary shape to that of the base part 12. The perimeter 58 typically has two locating lugs 60 for locating two of the corners of the base and top parts 12 and 14 against lateral movement. The perimeter 58 also has two cut-outs 62 located to match with the cut-outs 54 of the base part 12. The cut-out 62 have "V" shaped grooves 64 typically identical to the "V" shaped grooves 56. The cut-outs 54 and 62 form aperture 66 (see Figure 3A) to receive the inserts 15 (see Figure 3B) . Each insert 15 is generally rectangular in plan and has a "V" shaped rib 68 extending about it's perimeter. The rib 68 is of complementary shape to the grooves 56 and 64. It is envisaged that the cut-outs 54 and 62 and the inserts 15 could be replaced with apertures located entirely in the bottom part 12 or the top part 14.

The transceiver 46 is housed in a box 69 comprising a base part 70 and a cop part 72 each shaped to be secured together. Typically, the base part 70 has one or two recesses 74 to receive one or two connectors, such as, conventional D type connectors 76. The base part 70 and the top part 72 each have a semi-circular cut-out located to meet and form a hole 78 to receive a female BNC connector 80 (see also Figure 2) .

Within the box 46 there is located one or two transceiver circuits 82 (see Figure 7A) each transceiver circuit 82 typically comprises a coax transceiver interface 84 powered by a DC to DC converter 86, output isolation transformers 88 and one of the D-type connectors 76. The or each transceiver circuit 82 also includes the single D-type connector 80. Typically, the coax transceiver interface 84 consists of a receiver, a transmitter, a collision detector and a jabber timer. The transceiver circuit is of a conventional type, as may be configured with a National Semiconductor DP8392A/NS32492A Coaxial Transceiver Interface. The DC to DC converter 86 is required to achieve electrical isolation between the transceiver circuits 82 and the computer terminal 90 or the 1: :e to which the transceiver 46 is connected and powered via the transceiver cable 92. The transceiver cable

92 is provided with two D-type connectors 94, one for coupling with the D-type connector 76 of the transceiver 46 and the other for coupling with a conventional D-type connector 96 of the computer terminal 90 (see Figure 1) . It is envisaged that the aperture 66 could be located entirely in the top part 14 or the base part 12. The connector 76 of the transceiver 46 then being located either in it's top part 72 or base part 70 so as to overlie the aperture 66 for receiving one of the connectors 94 of the transceiver cable 92. The connectors 76 of the transceiver 46 and one of the connectors 94 of the transceiver cable 92 could be RJ45 type cable connectors. Typically, in such a case, a flat 3. telephone type cable is joined with the RJ45 connector at one end and the D-type connector at the other end. The telephone type cable is convenient since it is much less expensive than shielded cable and is typically smaller and thus less intrusive than shielded cable. Also, the flat telephone type cable is easier to route from the cabling junction box to the computer terminal 90. Preferably, wiring between the RJ45 connector and the D-type connector 94 is as shown in Figure 7B. The wiring is chosen so that should the RJ45 connector be wrongly crimped to the flat telephone cable, then the ground and V+ lines will not be connected across one of the isolation transformers 88 of the transceiver circuit 82 and accordingly destruction of such isolation transformer 88 can be avoided in those circumstances. In use, the base part 12 of the cabling junction box

10 is fixed to the cabling duct 100 (see Figure 1) or the like by screws or bolts fixed in appropriate ones of the apertures 24. The cables 28 are threaded through the apertures 26 and connected to the BNC T connector 32, as shown in Figure 2, thus completing the backbone cable 34. The top part 14 may, at that time, be fixed to the base part 12 via location of the hooks 19 into respective ones of the slots 16 in the event that the cabling junction box 10 is not about to be provided with one of the transceivers 46. That is, at this stage, the transceiver 46 need not be located within the cabling junction box 10 and need not be connected to the BNC T connector 32. Despite this, the backbone cable is complete and the LAN can function normally, as though the cabling junction box 10 of the BNC T connector 32 were not installed. This arrangement has the advantage that whilst a connection point is provided to the backbone cable, the connection point is not exposed to the general environment and is therefore less likely to be accidently disconnected or damaged. When it is intended to connect the computer terminal

90 to the back bone cable 34, the top part 14 is removed from the base part 12. One or both of the inserts 15 are then removed by sliding out of the cut-outs 54. One insert 15 is removed if only transceiver circuit 82 exists in the transceiver 46 and both inserts 15 are removed if there are two transceiver circuits 82. The female BNC connector 80 of the 5 transceiver 46 is then connected to the BNC T connector 32. The connection of the two cables 28, of the backbone cable 34, need not be disrupted during connection to the transceiver 46. The box 69 is then located in the region 44 with the or each D-type connector 76 disposed proximate the or each 10 aperture 66. The top part 14 is then re-attached to the base part 12. One of the D-type connectors 94 of the transceiver cable 92 may then be inserted into one of the D-type connectors 76 of the transceiver 46 and the other D-type connector 94 of the transceiver cable 92 is connected to the computer terminal 15 90 (see Figure 1) . It is to be noted that in the present invention, two computer terminals 90 or the like may be connected via the cabling junction box 10 to the backbone cable 34.

An advantage of the present invention is that upon

20 set-up of a LAN, the cabling junction boxes 10 can, at relative little cost, be located onto the backbone cable 34 at sites which computer terminals 90 or the like are expected or anticipated to be located. In this way, installation of the relatively more expensive transceivers 46 can be delayed until

25 a computer terminal 90 or the like is to be connected to the backbone cable 34. By the use of the cabling junction box 10, the integrity of the backbone cable 34 can be more easily ensured both before and after connection of the transceiver 46.

Once the transceiver 46 has been inserted the computer terminal

30 90 can easily and safely be connected and disconnected by plugging and unplugging the D-type connectors 94 through the apertures 66. By doing this, the possibility of accidental interruption of the backbone cable 34^'is virtually eliminated since such connection and disconnection does not involve use

35 of the BN connector 32.

Also, the use of the ledges 36 provides location of the BNC T connector 32 and the cables 28 when the transceiver 46 is not located within the cabling junction box 10. The ledges 36 further provide location of the box 69 when it is located within the cabling junction box 10. The raised ribs 80 provide for displacement of the box 69 from the base part 12 so as to avoid failing thereof with bolts or screws used in the apertures 24.

It is envisaged that the cabling junction box 10 and cabling system of the present invention could be used with LANs employing optical fibre cables and optical interface units. It is envisaged that the base part 12 could be in the form of a piece of cabling duct designed to receive the transceiver 46 and the top part 14 is a cover for the cabling duct.

Modifications and variations such as would be apparent to a skilled addressee are deemed within the scope of the present invention. For example, other types of multi- conductor cable connectors could be used. Also, the box 69 for the transceiver 46 could be made from metal material and designed to be in direct thermal contact with the Coaxial Transceiver Interface DP8392A.

Claims

1. A cabling junction box comprising: a base part having a coupling for electrically connecting two electrical cables at a junction and being adapted to house an electrical interface for connection to the junction; and, a top part removably attached to the base part, whereby, in use, the cabling junction box can facilitate connection to and disconnection from the junction without disruption of electrical signals through the junction.

2. A cabling junction box according to claim 1, having an aperture provided in one of a set comprising the top part, the base part, and the top and base parts in cooperation, the aperture providing access for connection to a further cable without the cabling junction box to the said interface.

3. A cabling junction box according to claim 1, in which the base part is chosen from a set including an open top box and a piece of cabling ducting.

4. A cabling junction box according to claim 1, in which the base part has a region designed to facilitate removable location of the interface therein.

5. A cabling junction box according to claim 2, in which the aperture overlies a connector of the interface for facilitating connection of the further cable.

6. A cabling junction box according to any one of claims 1 to 5, in which the base part has ledges spaced apart to define an opening to the region whereby, in use, the junction is supported by the ledges and is disposed part way through the

opening. 7. A cabling junction box according to any one of claims 1 to 5, in which the base part has a plurality of raised ribs traversing the said region whereby, in use, the raised ribs displace the interface from the base part to provide a clearance to avoid fouling therewith.

6. A cabling junction box according to any one of claims 1 to 5, in which the aperture is defined by the cooperation of the base and top parts, the cabling junction box also comprising an insert dimensioned to be retained in the aperture when the base and top parts are attached together.

9. A cabling junction box and an electrical interface, the cabling junction box comprising a base part having a coupling for electrically connecting two electrical cables at a junction and a top part removably attached to the base part, the interface processing electrical signals between the two electrical cables and a further cable whereby in use, the cabling junction box can facilitate connection to and disconnection from the junction without disruption of electrical signals through the junction.

10. A cabling junction box and an electrical interface according to claim 9 having an aperture provided in one of a set comprising the top part, the base part, and the top and base parts in cooporation, the aperture providing access for connection to a further cable without the cabling junction box to the said interface.

11. A cabling junction box and an electrical interface according to claim 9, in which the base part is chosen from a set including an open top box and a piece of cabling directing.

12. A cabling junction box and an electrical interface according to claim 7, in which the base part has a region designed to facilitate removable location of the interface 12.

therein.

13. A cabling junction box according to claim 10, in which the aperture overlies the connector of the interface for facilitating connection of the further cable.

14. A cabling junction box according to any one of claim 12 or 13, in which the base part has ledges spaced apart to define an opening to the region whereby, in use, the junction is supported by the ledges and is disposed part way through the opening.

15. A cabling junction box according to claim 12 or 13, in which the base part has a plurality of raised ribs traversing the said region whereby, in use, the raised ribs displace the interface from the base part to provide a clearance to the mounting means to avoid fouling therewith.

16. A cabling junction box according to any one of claims 10 to 13, in which the aperture is defined by the cooperation of the base and top parts, the cabling junction box also comprising an insert dimensioned to be retained in the aperture when the base and top parts are attached together.

17. A cabling junction box according to claim 14, in which a connector is mounted in a side of the interface and is disposed part way through the opening for connection with the junction.

18. A cabling system comprising a backbone cable formed from a plurality of electrical cables, connected together at a plurality of junctions, a plurality of cabling junction boxes one located at each said junction, each cabling junction box comprising a base part having a coupling for electrically connecting two electrical cables at a junction and a top part removably attached to the base part, the interface processing electrical signals between the two electrical cables and a further cable whereby in use, the cabling junction box can facilitate connection to and disconnection from the junction without disruption of electrical signals through the junction.

19. A cabling system according to claim 18, having an aperture provided in one of a set comprising the top part, the base part, and the top and base parts in cooporation, the aperture providing access for connection to a further cable without the cabling junction box to the said interface.

20. A cabling system according to claim 18, in which the base part is chosen from a set including an open top box and a piece of cabling directing.

21. A cabling system according to claim 18, in which the base part has a region designed to facilitate removable location of the interface therein.

22. A cabling system according to claim 19, in which the aperture overlies the connector of the interface for facilitating connection of the further cable.

23. A cabling system according to claim 19, in which the base part has ledges spaced apart to define an opening to the region whereby, in use, the junction is supported by the ledges and is disposed part way through the opening.

24. A cabling system according to claims 19 to 24, in which the base part has a plurality of raised ribs traversing the said region whereby, in use, the raised ribs display the interface from the base part to provide a clearance to avoid fouling therewith.

25. A cabling system according to any one of claims 19 to 24, in which the aperture is defined by the cooperation of the base and top parts, the cabling junction box also comprising an insert dimensioned to be retained in the aperture when the base and top parts are attached together.

26. A cabling system according to claim 23 in which the connector is mounted in a side of the interface and is disposed part way through the opening for connection with the junction.

27. An interface for use with a cabling junction box comprising a base part having a coupling for electrically connecting two electrical cables at a junction and being adapted to house an electrical interface for connection to the junction and a top part removably attached to the base part, the interface comprising a box dimensioned for location in and removal from the cabling junction box, a connector located for connection to the junction and a further connector for connection to a further cable whereby, in use, the interface box allows connection to and disconnection from said junction without disruption of electrical signals through the junction.

28. An interface according to claim 27, having a connector mounted in a side of the box of the interface and is disposable partly through the opening for connection with the coupling.

29. An interface according to claim 27 or 28, having a further connector which overlies the aperture in the cabling junction box, when in use, the further connector disposed for receiving a further electrical cable.