The present invention relates to field communication distribution equipment and, more particularly, to improvements in cables for such equipment to increase data throughput of such cables without increasing cross-talk and other interference between data communication channels between the distribution equipment.
The J-1077 A/U distribution box (hereinafter referred to simply as the “J-1077”) is used to interconnect military field telephones and other communication devices in mobile, transportable, and semi-permanent installations. The J-1077 has provisions for connection of one or two 26 conductor-pair cables to a set of 26 pairs of spring post connectors mounted on a panel within the box. The standard cable for use with J-1077 type boxes is designated CX-4566 A/G. As such, the J-1077 can interconnect two 26-pair cables or can terminate a single 26-pair cable and provide connections to the conductors within the cable, such as for telephone sets or test equipment. The J-1077 has been in use for several decades and has proved to be generally rugged and reliable in varied field conditions. Additional information about the J-1077 distribution box can be obtained from Associated Industries of North Hollywood, Calif. (www.associated-ind.com) and from other sources.
Although generally successful, the J-1077 has some shortcomings. The configuration of the spring post connectors requires that wires be stripped before insertion into the posts. Stripping sometimes damages some of the strands of a conductor, causing them to break off, thereby reducing the signal carrying capability of the conductor. Stripping is also time-consuming if a large number of connections need to be made at one time.
Another problem with the J-1077 is that if a communication malfunction occurs in a system using J-1077 distribution boxes and cables, it is often difficult and time-consuming to isolate the problem among the possible 26 circuits which may be in use. At present, the usual procedure is to disconnect and reconnect each wire until the problem is isolated. A related problem is detecting the location of a break or cut in the cable or unauthorized connections to the network, such as by an enemy. Additionally, there are no provisions on a standard J-1077 box for connection of computers thereto to enable field networking of computers or data communication between computerized devices using the J-1077 system.
Some types of military communication equipment have optical data signal interfaces which utilize optical fiber communication media. Optical data signals have a number of advantages in military applications, including high efficiency over long distances, high data rates, difficulty of tapping by an enemy, and the like. There is also a need for converting signals carried by optical fiber media to electrical data signals for carriage by conventional copper based cables.
The J-1077 distribution box and the standard CX-4566 A/G cable, were originally designed for carrying multiple channels of audio frequency telephone signals. As stated above, military field communications have evolved beyond voice and teletype communications to high speed data communications for text, numeric, and image data in addition to voice signals. It is desirable that such communications be carried on using standard data communication protocols to enable existing equipment and devices to be used to thereby avoid the expense need for designing
The present invention provides an enhanced cable for field data distribution systems. In particular, the present invention provides embodiments of cables for interconnection of J-1077 type distribution boxes which have been upgraded for carrying computer network signals, such as Ethernet type signals.
In the present invention, the spring post connectors of conventional J-1077 boxes are replaced by sets of insulation displacement connectors (IDC) mounted on a connector panel. Each insulation displacement connector generally has a movable top section which comprises two wire insertion holes and a lower fixed section which houses a pair of terminal strips. The terminal strips have a wire engaging portion at one end for engaging and making electrical contact with a wire. The terminal strips are generally parallel to one another but offset to provide a sufficient dielectric strength between them. In order to establish an electrical connection between the wires and the terminal strips a user first opens the top section, i.e., pivots the top section to its open position, inserts the pair of wires, and then closes the top section. Upon closing the top section of the connector, the wires are forced through the terminal strip engaging portion to make electrical and mechanical contact with the terminal strips. To remove the wires and/or break the electrical connection, the process is reversed. Each spring binding post on the connector panel of the J-1077 distribution box is replaced by an insulation displacement connector unit. The connectors of the present invention are mounted on the J-1077 panel in pairs in the same manner as the spring binding posts they replace.
The connectors typically carry audio frequency communication signals. In order to facilitate troubleshooting to find which circuit may have a problem, it is a common practice to remove a conductor from a binding post, one at a time, until the problem circuit is identified. Such disconnecting and reconnecting is laborious and can damage the stripped wire ends, requiring that the wire end be stripped before reconnecting. The present invention overcomes this problem by providing a test switch in at least one conductor of each pair. By this means, the test switch can be opened to disconnect the circuit instead of physically removing the conductor from the connector. Preferably, a double pole, single throw switch is connected between the pairs of terminals of the pair of connector devices.
The present invention provides a means of detecting the approximate location of a cut or break in one of a series of interconnected cables of the type that are used with the J-1077 distribution box. Typically, the cables are formed by 26 numbered pairs of conductors. Normally, only 25 pairs carry communication signals, while the No. 26 pair is used for testing and troubleshooting purposes. The present invention provides at least one resistor per cable, connected across the No. 26 conductor pair. When a plurality of cables are interconnected end to end by J-1077 boxes, the resistors of the cables are connected in parallel. If the resistance of the parallel combination is measured, the number of unbroken cable sections can be determined from the composite resistance and compared with the composite resistance expected from the number of cables present.
A standard resistor may also be connected across each end of the No. 26 pair of each cable section. By this means, the integrity of a single cable section can be determined by measuring the resistance across the No. 26 conductor pair.
In order to provide for digital communications between computers and computerized equipment, the improved J-1077 type distribution box of the present invention may have some of the insulation displacement connectors interconnected to connectors more appropriate for computer networks or for interconnections between modems. Such connectors can include, but are not limited to, RJ-45 (8P8C), RJ-11, and RJ-12 modular type connectors; BNC type connectors; and other connectors commonly employed for interconnections between computers. Conductors of the cables interconnecting the improved J-1077 boxes and carrying data between computers may be shielded separately from the other conductor pairs to minimize possible interference to and from other signals on other conductor pairs. Data connectors and associated cable conductors would provide some limited computer networking capabilities in addition to more conventional analog voice communications in systems employing J-1077 type distribution boxes. Alternatively, other types of connectors can be connected to selected insulation displacement connectors, such as standard phone connectors, F-type connectors, fiber optic adapters, and other standard types of network, telephone, audio, video, and signal connectors. The insulation displacement connectors and the auxiliary connectors are connected to a pair of box connectors positioned on opposite sides of the box to enable the distribution box to be connected to other boxes. The box connectors have sets of contacts which correspond to the conductors of the insulation displacement connectors and the auxiliary connectors. A preferred type of box connector is designated U-187 A/G which is referred to as a side mount connector in which a side of the box connector structure is joined to the side wall of the box. It is foreseen that the box connector could alternatively be a U-186 C/G connector which is substantially similar to the U-187 A/G except that the U-186 C/G connector is joined to a side wall of the box by an end of the connector structure.
An embodiment of the distribution box of present invention is provided with a media converter for converting between optical data signals and electrical data signals. A standard type of fiber optic connector is provided on the connector along with a standard type of electrical data connector. The fiber optic connector may, for example, be an ST type of optical connector while the electrical connector is an RJ-45 connector. Media converter circuitry is interfaced to the optical and electrical data connectors and bilaterally converts between a standard optical data format and a standard electrical data format. The formats may, for example be 1000Base-SX for the optical data format and 1000Base-T for the electrical data format. Electrical power for operation of the media converter circuitry may be provided by a transformer and rectifier unit connected to a power strip or generator, a battery of an appropriate size, or the like.
In one embodiment of the invention, an enhanced cable includes a plurality of pairs of cable conductors positioned within a conductive shield and an insulative tubular sheath. The cable may also include an outer “armor” layer which reduces damage from being chewed by animals and from other hazards. Each end of the cable includes a cable connector with a plurality of sets of contacts to which the cable conductors are connected. The cable connector is configured to be compatible with the configuration of the box connector. The conductor pairs, in cooperation with the cable connector, are configured to comply with Category 5E specifications, often referred to as Cat 5E. Category 5E conductor pairs are typically twisted at a twist pitch of three twists per inch (2.54 cm). Preferably, the twist is maintained within the cable connector to within one-half inch (12.7 mm) of the contact terminal set to which the conductors are soldered. It is foreseen that the conductor pairs and connector could be configured to specifications more stringent than Category 5E.
Typically, both ends of the enhanced cable will have U-185 B/G connectors which are compatible with both the U-187 A/G and U-186 C/G box connectors. The U-185 B/G connector is a “genderless” type of connector and may also be connected to another U-185 B/G connector to thereby connect one cable to another cable. The cable may also be provided at one end with another type of connector, such as a standard type of multi-contact cylindrical connector designated MS-27467 or AE167, often referred to as a barrel or Cannon connector.
Various objects and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention.
The drawings constitute a part of this specification, include exemplary embodiments of the present invention, and illustrate various objects and features thereof.
As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure.
Referring to the drawing in more detail, the reference numeral 1 (
Referring to
The insulation displacement connector 5 generally has a movable top section 21 which comprises two wire insertion holes and pivotally connected to a lower fixed section 22 which houses a pair of terminal strips. The terminal strips (not shown) have a wire engaging portion at one end for engaging and making electrical contact with a wire. The terminal strips are generally parallel to one another but offset to provide a sufficient dielectric strength between them. The top movable section 21 of the connector 5 pivots about a fixed axis located toward the back side of the connector. The top section 21 has a movable latch member to maintain the top section in its closed position. To open the top section, a user the top section to its raised or open position (
Each set spring binding posts 15 on the connector panel of the conventional J-1077 distribution box 14 is replaced by a set 4 of insulation displacement connector units or connector devices 5. The pair of connector units 5 provides for redundancy should one of the receptacles malfunction or be damaged. The insulation displacement connectors 5 enable faster and more reliable connections since the wires to be inserted do not require stripping. The terminals 5′ (
In order to facilitate troubleshooting to find which circuit may have a problem, it is a common practice with the older box 14 to remove a conductor from a binding post 15, one at a time, until the problem circuit is identified. Such disconnecting and reconnecting is laborious and can damage the stripped wire ends, requiring that the wire end be stripped before reconnecting. The present invention overcomes this problem by providing a test switch 6 to interconnect the sets of terminals of each pair 4 of connector units 5. A double pole, single throw switch configuration is preferred. When the switch contacts are closed, the terminals of each pair 4 are interconnected. However, when the switch contacts are opened, the conductors of cables 9 on both sides of the box 1 can be individually tested, without removing wires from the connector units 5.
The present invention provides a means of detecting the approximate location of a cut or break in one of a series of interconnected cables 9. Typically, the cables 9 are formed by 26 numbered pairs of conductors. Normally, only 25 pairs carry communication signals, while the No. 26 pair is used for testing and troubleshooting purposes.
Referring to
For example, if the composite cable is formed by ten cable sections, each with a standard resistor connected across the No. 26 pair, then the equivalent resistance measured is one tenth of the value of the standard resistor. However, if ten cable sections should be present and the resistance measured by an ohm meter 30 from one end is, for example, one seventh the value of the standard resistor, then the technician knows that there is a break in the eighth section. By this means, the broken cable section can be replaced or repaired quickly and directly without the need to inspect each section. Alternatively, resistor 28 may be connected across each end of the No. 26 pair of each cable section 9. By this means, the integrity of a single cable section 9 can be determined by measuring the resistance across the No. 26 conductor pair.
The present invention also contemplates connecting a cable monitor circuit to the No. 26 cable pair which monitors the equivalent resistance of the composite cable. Such a cable monitor would preferably be based on a programmable digital computer or at least a programmable microprocessor to provide for a variety of desirable features. The number of sections and the value of the standard resistor are entered into the monitor circuit. If the monitored resistance varies by greater than a selected tolerance, an alarm is activated. The change in resistance could be a consequence of the cable being damaged or being disconnected by an enemy to insert listening equipment into the line. In either case, once the occurrence to line interruption has been alerted, the approximate location of the break can be located by the procedures described previously.
In some applications, it may be desirable to provide in-line electrical fuses (not shown) to the conductors of the cable to protect circuits and equipment connected thereto. Such fuses may be rated at relatively low levels of current, such as 375 milliamperes, because of the relatively low power levels of signals intended to be carried by the conductors of the system. The fuses protect the circuits connected thereto from damage due to short circuits, current surges, and the like. The fuses are preferably provided in such a manner that they can be easily replaced if blown.
In order to provide for digital communications between computers and computerized equipment, the improved type distribution box 1 of the present invention may have various types of auxiliary connectors 7 having auxiliary connector terminals 7′ interconnected to the terminals 5′ of the insulation displacement connector units 5. Such connectors can include, but are not limited to, RJ-45 (8P8C), RJ-11, and RJ-12 modular type connectors; BNC type connectors; F-type connectors, fiber optic adapters, and other connectors commonly employed for interconnections between computers, computer networks, modems, and the like. Conductors of the cables 9 interconnecting the boxes 1 and carrying data between computers may be shielded separately from the other conductor pairs to minimize possible interference to and from other signals on other conductor pairs. Data connectors and associated cable conductors would provide some limited computer networking capabilities in addition to more conventional analog voice communications in systems employing conventional J-1077 type distribution boxes.
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The circuit board 120 and support blocks 124, 126, and 130 support a plurality of conductive contact members 134. Each contact member 134 includes a straight solder lug 136 with means such as an aperture 138 to receive a stripped end of a conductor 83 of a conductor pair 81. At an end opposite the aperture 138, a resilient contact pad 140 is formed. The illustrated contact pad 140 has a wide V-shaped ridge 142. When a cable connector 79 is joined with a box connector 56 or another cable connector 79, the ridges 142 of mutually engaging contacts 134 snap past one another to help retain the connectors together. The circuit board 120 is preferably a multi-layer circuit board with one or more internal ground plane layers (not shown) to form a shield in cooperation with the conductive shell 94. The solder lugs 136 of the contact members 134 extend through holes (not shown) in the circuit board 120 and are retained therein against the support blocks 124, 126, and 130. Each contact member 134 corresponds to a conductor 83. Each contact member 134 is replicated at opposite ends of the assembly 94 with internal traces (not shown) interconnecting the pairs of contacts 134. The patterns of contact members 134 at opposite ends of the contact array board assembly 94 are mirror images of one another so that when a cable connector 79 is connected to another cable connector or to a box connector 56, the signals are channeled to the correct conductor pairs 81.
The structure of the cable member 77 and the connectors 79 cooperate to enable the enhanced cable assembly 75 to comply with, or exceed, specifications of Category 5E, also known as Telecommunication Industry Association TIA/EIA-568-B standards. Category 5E incorporates the older Category 5 standards which enable cables to carry signals up to 100 MHz, including 100Base-T and 1000Base-T signals. Category 5E is enhanced from Category 5 with improved “far end” crosstalk performance.
In the illustrated enhanced cable assembly 75, the twist of the conductor pairs 81 is maintained within the cable connector 79 to within one half inch (12.7 mm) of their soldered connection to the solder lugs 136 of the contact members 134. This is illustrated as distance D in
It is to be understood that while certain forms of the present invention have been illustrated and described herein, it is not to be limited to the specific forms or arrangement of parts described and shown.
This is a continuation-in-part of U.S. patent application, Ser. No. 12/033,296, filed Feb. 19, 2008 for FIELD DATA DISTRIBUTION SYSTEM WITH FIBER OPTIC CONVERTER, which is a continuation-in-part of U.S. patent application, Ser. No. 11/803,888, filed May 16, 2007 for FIELD COMMUNICATION AND COMPUTER DATA DISTRIBUTION SYSTEM, which is a continuation of U.S. patent application, Ser. No. 11/168,580 filed Jun. 28, 2005 for FIELD COMMUNICATION AND COMPUTER DATA DISTRIBUTION SYSTEM, which issued as U.S. Pat. No. 7,238,063 and which claims priority under 35 U.S.C. 119(e) and 37 C.F.R. 1.78(a)(4) based upon U.S. Provisional Application, Ser. No. 60/583,505 for FIELD COMMUNICATION AND COMPUTER DATA DISTRIBUTION SYSTEM, filed Jun. 28, 2004; the disclosures of Ser. Nos. 12/033,296, 11/803,888, and 60/583,505 and U.S. Pat. No. 7,238,063 being incorporated herein by reference.
Number | Date | Country | |
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60583505 | Jun 2004 | US |
Number | Date | Country | |
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Parent | 11168580 | Jun 2005 | US |
Child | 11803888 | US |
Number | Date | Country | |
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Parent | 12033296 | Feb 2008 | US |
Child | 12355596 | US | |
Parent | 11803888 | May 2007 | US |
Child | 12033296 | US |