AU662632B2 - A monitoring device for a U-link - Google Patents

Description

OPI DATE 13/12/93 APPLN. ID 40529/93 I111111 11111 1111111 AOJP DATE 24/02/94 PCT NUMBER PCT/AU93/00235 II III 11111I1111111111111111I I i111111111 AU9340529 INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (51) International Patent Classification 5 (11) International Publication Number: WO 93/23961 H04Q 1/20, HOIR 13/66 Al (43) International Publication Date: 25 November 1993 (25.11.93) (21) International Application Number: PCT/AU93/00235 (74) Agents: WEBBER, David, Brian et al,; Davies Collison Cave, I Little Collins St., Melbourne, VIC 3000 (AU).

(22) International Filing Date: 21 May 1993 (21.05.93) (81) Designated States: AT, AU, BB, BG, BR, CA, CH, CZ, Priority data: DE, DK, ES, FI, GB, HU, JP, KP, KR, KZ, LK, LU, PL2562 21 May 1992 (21.05.92) AU MG, MN, MW, NL, NO, NZ, PL, PT, RO, RU, SD, SE, SK, UA, US, VN, European patent (AT, BE, CH, DE, DK, ES, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE), (71) Applicant (for all designated States except US): TELSTRA OAPI patent (BF, BJ, CF, CG, CI, CM, GA, GN, ML, CORPORATION LIMITED [AU/AU]; A.C.N. 051 775 MR, NE, SN, TD, TG).

556, 242 Exhibition Street, Melbourne, VIC 3000 (AU).

(72) Inventor; and Published Inventor/Applicant (for US only) SOMERVILLE, John, With international search report.

Stuart [AU/AU]; 4 Dresden Court, Modbury Heights, S.A. 5092 6 2 6 2 (54) Title: A MONITORING DEVICE FOR A U-LINK 2 14- (57) Abstract A monitoring device (20) for a U-link including a port (22) for attaching the device to the U-link and a contact port (24, 26, 28) for making electrical contact with a conductor of the U-link without disrupting a communication service provided on the U-link h c

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WO 93/23961 PCT/AU93/00235

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A MONITORING DEVICE FOR A U-LINK The present invention relates to a monitoring device for a U-link.

U-links are commonly employed in patch panels and telecommunication distribution frames to interconnect incoming and outgoing communications lines. Coaxial cable U-links are used extensively in digital distribution frames (DDF) of telecommunication systems to connect telecommunication equipment. Whilst monitoring U-links can be purchased which incorporate a facility to enable monitoring of the data transmitted on the link without affecting line impedance, such links are expensive. Most of the links which have been used on distribution frames do not include a monitoring facility. Therefore, if a telecommunications network provider needs to monitor the lines connected to the link, so as to analyse a fault or determine whether one is present, the link needs to be removed and replaced with a monitoring U-link that includes the monitoring facility. A monitoring link would include, for example, an additional coax connector stub which is connected to the conductor connecting the other coax connectors of the link. The additional connector enables monitoring equipment to be connected to the link to analyse data transmitted on the conductor.

Removal of a U-link disconnects the service provided on the line formed by the link, and network providers need to advise a customer whbn the service is to be disrupted for any length of time. This represents an onerous requirement as a time must be arranged with the customer for disconnection of each link. The problem is exacerbated when a link carries data for more than one customer. For example, multiplexing of services may result in a link carrying data for up to 10,000 customers. Also in the case of corporate customers, such as banks and other financial institutions, even a three second disconnection is considered extremely disruptive. This places a considerable burden on the network manager who has to negotiate with a customer an appropriate time to disconnect the service. Negotiations with one customer may take up to ten days.

The present invention provides a monitoring device for a U-link, comprising means for attaching said device to said U-link, and means for making electrical contact 1 1 1 WO 93/23961 PC/AU93/00235 -2with a conductor of said U-link. without disrupting a communications service provided on said U-link.

Preferably the attaching means enables attachment of said device to a port of said U-link.

Preferably said contact means includes conducting probe means having an impedance which minimises the affect on said service of making said contact.

Preferably said contact means includes conducting probe means which moves relative to said attaching means to make said contact after attachment of said device to said U-link.

Preferred embodiments of the present invention are hereinafter described, by way of example only, with reference to the accompanying drawings, wherein: Figure 1 is a perspective view of a preferred embodiment of a monitoring device to be inserted into a port of a coaxial U-link; Figure 2 is a longitudinal cross-sectional view of the monitoring device; Figure 3 is a side view of a coaxial connector of the device; Figure 4 is a side view of a probe assembly of the device; Figure 5 is an end view of a nut of the device; Figure 6 is a longitudinal cross-sectional view of the nut; t Figure 7 is a longitudinal cross-sectional view of a teflon insert of the device; and Figure 8 is a partial longitudinal cross-sectional view of a body part of the device.

A 'coaxial U-link 2, as shown in Figure 1, includes two coaxial connectors 4 which form the legs of the link 2 and are electrically connected in the head 6 of the link 2 by a conductor 8. The conductor 8 extends along the length of the head 6 and is soldered at each end to one of the connectors 4. An open port 10 is provided at each end of the head 6 through which soldering of the conductor 8 to the connectors 4 can be performed. The ports 10 include a threaded rim 12 onto which a dust cover 14 is -I WO 93/23961 PCT/AU93/00235 -3screwed after the conductor has been soldered so as to close the port 10. U-links of the type shown in Figure 1 are manufactured by Siemens and N.V. Phillips and are used extensively on digital distribution frames to connect coaxial cables.

A monitoring device 20, as shown in Figures 1 and 2, includes a body part 22, a modified coaxial connector 24, a nut 26 and a probe 28. The connector 24 is a Siemens coaxial connector, part number C42334-A76-A14, which is modified by machining away the tail section 32 (shown in broken lines) opposite the connector end 34, as shown in Figure 3. This allows the probe 28 to be connected to the tail end 36 of the connector 24. Other coax connectors with removed tail sections can also be used.

The probe 28 is a gold springloaded probe, preferably probe number EPA-25L4 produced by Fabrication Australia Pty. Ltd. A 1.5KS2 resistor 30, with its legs cut down, is i soldered at one end to the tail end 36 of the connector 24, as shown in Figure 4, so as to be electrically connected with the inner conductor of the connector 24. The other leg of the resistor 30 is soldered to the end of the probe 28 opposite the crown shaped probe tip 38.

A teflon insert 40, as shown in Figure 7, is cylindrical and includes an inner channel 42 which is specifically designed to receive the probe 28 and resistor assembly, as shown in Figure 2. The insert 40 insulates the probe from the remaining parts of the monitoring device 20 and is designed to have an interference fit with the probe and resistor assembly. The insert 40 has an end portion 44 with a smaller diameter than the remainder of the insert 40 and is opposite the end 46 of the insert 40 which abuts the tail end 36 of the connector 24. The length of the insert 40 is such that the probe tip 38 just extends from the end portion 44 when it is fully depressed against the Sbias of the inner spring of the probe 28.

The nut 26 is made of metal and is configured to allow the coaxial connector 24 to be slotted therein. The nut 26 has a reduced diameter end 48 which engages the tail 50 of the connector 24. The connector 24, resistor 30 and probe 28 assembly, as shown in Figure 4, can therefore be slotted into the nut 26 so as to allow the connector 24, except the tail 50, to extend through the end 48 as shown in Figure 2. The assembly is L WO 93/23961 PCT/AU93/00235 -4attached to the nut 26 by a lock nut 52, as illustrated in Figure 1, which is screwed onto the thread 54 of the connector 24 so as to clamp the reduced diameter end 48 between the tail 50 of the connector 24 and the lock nut 52.

The body part 22, which is also made of metal, is cylindrical and configured to receive the teflon insert 40, as shown in Figure 2. The inside diameter of the body 22 corresponds to the outer diameter of the insert 40, and also includes a reduced diameter end portion 60, corresponding to the end portion 44 of the insert 40. The inner wall 62 of the body 22 tapers from its main diameter to the reduced diameter at a point corresponding to the point when the insert 40 steps to the reduced diameter of the end portion 44. The outer wall 64 of the body 22 also tapers towards a reduced diameter at the end portion 60, as shown in Figure 8. The end portion 60 has an outer diameter which corresponds to the diameter of the ports 10 of the U-link 6. The outer wall of the end portion 60 includes a thread 66 configured to engage the threaded rim 12 of a port 10, until the end of the head 6 of the link 2 abuts the tapered portion 68 of the body 22.

The outer wall of the body 22 also includes a middle thread 70, and an end thread 72, at the end of the body 22 opposite the end 78 with the port thread 66. Both of the threads 70 and 72 are spaced by a machined annular recess 74. The middle thread and the end thread 72 are configured to cooperate with an inwardly protruding thread 76 on the inner wall of the nut 26, at the end of the nut 26 opposite the reduced diameter end 48. The threads 70, 72 and 76 are provided to allow the nut, with the connector 24, resistor 30 and probe 28 assembly to be screwed onto the end of the body 22 so the teflon insert 40 fits within the body, as shown in Figure 2. Fine knurls 76 are included on the outer surfaces of both the nut 26 and the body 22 so as to provide surfaces which can be gripped when screwing the nut 26 relative to the body 22.

The length of the middle thread 70 is such that the body 22 can be screwed away from the connector 24 so the port engaging end 78 is disposed a shorter distance from the probe tip 38, as shown in Figure 1. With the body 22 extended in this manner, the end 78 can be screwed onto the port 10 so as to attach the monitoring device 20 to the link 2 without the probe 38 contacting the conductor 8. The nut 26 is then screwed onto r -I-

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-iillll.l.l.~l~_ the body 22 so as to move the probe 38 into open port 10 to contact the conductor 8.

The probe 38 and the conductor 8 are both centrally aligned with respect to the body 22 and port 10. As the nut 26 is screwed fully onto the body 22, as shown in Figure 2, the probe 28 is compressed by the conductor 8 against its inner compression spring, which acts to bias the probe tip 38 onto the end of the conductor 8 so as to form a sound electrical contact. With the device 20 attached to the link 2 and the contact made, a coaxial cable or monitoring apparatus may be attached to the connector 24 so as to monitor and analyse the signals and data transmitted on the line formed by the link 2.

Connection of the device 20 to the link 2 does not disrupt the service provided on the line. The resistor 30 is chosen so that any test or monitoring equipment connected to the connector 24 has a minimum effect on the impedance of the line or data transmitted on the link 2. Also, although the probe tip 38 could be screwed directly onto the conductor 8 as the device 20 is attached to the link 2, the ability to affix the device 20 to the link 2 first, and then move the probe 28 into position, is particularly advantageous. This guards against any short circuit which could occur if the electrical contact with the conductor 8 is established as the device 20 is screwed onto the link 2.

The monitoring device 20 is a relatively cheap and simple tool which allows a U-link to be monitored without having to disconnect the link and without disrupting any services provided on the link.

Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise'", or variations such as "comprises" or 25 "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

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Claims (14)

1. A monitoring device for a U-link, comprising means for attaching said device to said U-link, and means for making electrical contact with a conductor of said U-link without disrupting a communications service provided on said U-link.

2. A monitoring device as claimed in claim 1, wherein said attaching means enables attachment of said device to a port of said U-link.

3. A monitoring device as claimed in claim 1, wherein said contact means includes conducting probe means having an impedance which minimises the affect on said service of making said contact.

4. A monitoring device as claimed in claim 1, wherein said contact means includes conducting probe means which moves relative to said attaching means to make said Scontact after attachment of said device to said U-link.

A monitoring device as claimed in claim 3 or 4, wherein said contact means includes a connector which enables connection of said device to communications equipment, said connector being connected to said probe means.

6. A monitoring device as claimed in claim 5, wherein said contact means includes a cooperating portion attached to said connector which engages said attaching means and is movable towards an engagement end of said attaching means which effects said 25 attachment to said U-link.

7. A monitoring device as claimed in claim 6, wherein said probe means is disposed in said attachment means and has a contact end which, in use, protrudes from said engagement end to make said contact.

8. A monitoring device as claimed in claim 7, wherein said probe means includes a spring to bias said contact end against said conductor after making said contact. 950713,p:\opet\dbw,40529.93,6 4 -7- -7

9. A monitoring device as claimed in claim 8, wherein said probe means includes a probe and series resistor.

A monitoring device as claimed in claim 9, wherein said probe means is mounted within an electrical insulating portion.

11. A monitoring device as claimed in claim 10, wherein said cooperating portion is a nut which screws onto cooperating threads of said attaching means.

12. A monitoring device as claimed in claim 11, wherein said engagement end includes a thread which screws into a port of said U-link. S

'13. A monitoring device as claimed in claim 2, wherein said attaching means includes an engagement end which screws into said port.

14. A monitoring device substantially as hereinbefore described with reference to the accompanying drawings. DATED this 13th day of July, 1995 TELSTRA CORPORATION LIMITED By its Patent Attorneys 4 25 DAVIES COLLISON CAVE 97I13,p\opr\db ,46529.93,7 Sii i I. II