Disclosed herein is a system and method for identifying individual coaxial cables in a bundle of coaxial cables. The system includes a coaxial cable header that is configured for receiving one or more coaxial cables and establishing electrical conductive contact with only a conductive shield on a first end of each cable. The system also includes an electrical tester that is electrically connected to the coaxial cable header such that the electrical tester is configured to transmit signals through the conductive shields of each cable. The electrical tester includes a test probe that is configured to be selectively connected to a second end of each cable. The electrical tester is configured to identify whether the second end of a particular cable that is connected to the test probe corresponds with the first end of a pre-determined cable that is within the coaxial cable header.

FIELD OF THE INVENTION

The present invention relates to a header for ribbonizing a coax cable, and a method of assembling and ribbonizing a coax cable.

BACKGROUND OF THE INVENTION

As described in U.S. Pat. No. 6,580,034, which is incorporated by reference, certain demanding applications require miniaturized multi-wire cable assemblies. To avoid undesirably bulky cables when substantial numbers of conductors are required, very fine conductors are used. Coaxial wires having shielding are commonly used for the conductors to limit electrical noise and interference. In a coaxial wire, a central conductor is encapsulated by a dielectric sheath, the dielectric sheath is surrounded by a conductive shielding brade and the conductive shielding brade is encapsulated by an outer jacket. A bundle of such wires is surrounded by a conductive braided shield, and an outer protective sheath (see FIG. 4 of U.S. Pat. No. '034).

Some applications requiring many different conductors prefer that a cable be very flexible, supple, or “floppy.” In an application such as a cable for connection to a medical ultrasound transducer, a stiff cable with even moderate resistance to flexing can make ultrasound imaging difficult. However, with conventional approaches to protectively sheathing cables, the bundle of wires may be undesirably rigid.

Cable assemblies having a multitude of conductors may be time-consuming and expensive to assemble with other components. When individual wires are used in a bundle, one can not readily identify which wire end on a first end of a cable bundle corresponds to a selected wire at the second end of the cable bundle, requiring tedious continuity testing. Normally, the wire ends at the first end of the cable bundle are connected to individual pads on a connector or printed circuit board, the shields at the first end are connected to a common ground pad on the connector or printed circuit board, and the connector or board is connected to a test facility that energizes each wire, one-at-a-time, so that an assembler can connect the identified wire end to the appropriate connection on a second connector or board.

However, because the shields are connected to the same ground pad at the first end of the cable bundle, false identifications can occur where more than one center conductor is shorted to a conductive shield at the second end of the cable. Center conductors are often shorted to their own shields through the act of cutting the coax cables to a specified length which crushes the cable ends so that the center conductors and strands of the conductive shield can make contact. Clearing the shorts and/or re-terminating the cables is time consuming and can damage the coax cable.

The device disclosed herein allows for identification using individual shields before the coaxial cables are terminated and ganged together.

SUMMARY OF THE INVENTION

According to one aspect of the invention, a header for a coaxial cable assembly is provided. The coaxial cable assembly comprises a first housing portion that is configured for receiving a plurality of coaxial cables; a second housing portion for mating with the first housing portion to capture the plurality of coaxial cables received by the first housing portion; and a plurality of contacts mounted to either the first housing portion or the second housing portion that are each configured to pierce an outer jacket and contact a conductive shield of a respective coaxial cable upon mating the first housing portion with the second housing portion.

According to another aspect of the invention, a system for identifying individual coaxial cables in a bundle of coaxial cables is provided. The system comprises a coaxial cable header that is configured for receiving one or more coaxial cables and establishing electrical conductive contact with a conductive shield on a first end of each cable; and an electrical tester that is electrically connected to the coaxial cable header such that the electrical tester is configured to selectively transmit signals through the conductive shields of each cable. The electrical tester includes a test probe that is configured to be selectively connected to a second end of each cable. The electrical tester is configured to identify whether the second end of a particular cable that is connected to the test probe corresponds with the first end of the cable to which a signal is applied by the electrical tester.

According to yet another aspect of the invention, a method for identifying individual coaxial cables in a bundle of coaxial cables is provided. The method comprises the steps of: (a) mounting first ends of a plurality of coax cables in respective slots of a coaxial cable header; (b) establishing electrical conductive contact between the cables and the coaxial cable header; (c) electrically connecting the coaxial cable header to an electrical tester; (d) transmitting a signal through a first end of a pre-determined cable of the bundle of coaxial cables that is mounted to the coaxial cable header by way of the electrical tester; (e) connecting a test probe of the electrical tester to a second end of each cable of the bundle of coaxial cables; and (f) identifying whether the second end of a particular cable of the cable bundle that is connected to the test probe corresponds with the pre-determined cable through which the signal is transmitted by way of the electrical tester.

DETAILED DESCRIPTION OF THE INVENTION

Referring now toFIGS. 1A and 3,FIG. 1Adepicts a schematic view of a system for identifying individual coax cables in a bundle of coax cables, whereasFIG. 3depicts a method of identifying individual coax cables in a bundle of coax cables. The system10ofFIG. 1Acomprises a bundle of eight discrete coaxial cables12A-12H (referred to collectively as cables12or individually as cable12), two coax ribbonizing headers14(1) and14(2), a plug16that is mechanically and electrically connected to the header14, a multi-channel electrical tester18that is electrically connected to the plug16by a series of wires20.

The headers14(1) and14(2) are structurally and functionally equivalent. The header14(2) is shown detached from the cables12inFIG. 1A. The headers14are described in greater detail with reference toFIGS. 2A-2G. The system10provides a rapid and convenient way to identify the cables12using the headers14and the multi-channel electrical tester18.

According to one exemplary embodiment of the invention, the electrical tester18is a multi-channel continuity tester. The electrical tester18may, however, vary from that which is shown and described. For example, the electrical tester18may be a multi-meter or a volt meter. The electrical tester18may have any number of channels, including a single channel. The electrical tester18may be configured to transmit and measure resistance, capacitance, voltage, signal frequency, signal waveform, or signal amplitude values, for example, across each cable12.

Described hereinafter is an exemplary method of utilizing the system10to identify individual coax cables12in the bundle of coax cables. It should be understood that the method is not limited to any particular step or sequence of steps and may vary from that which is shown and described hereinafter.

According to the exemplary method, at step100, the header14(1) is mechanically and electrically connected to the plug16such that the channels A-H of header14(1) are connected to the channels A-H of the plug16, respectively. Although not shown, the plug16may have pins or sockets that engage with sockets or pins, respectively, of the header14(1) in order to accomplish the connection.

At step102, the plug16is electrically connected to the electrical tester18by a series of wires20such that the channels A-H of the plug16are electrically connected to the channels A-H of the electrical tester18.

At step104, the first end of each cable12(e.g., end12(A)(1) of cable12A) is fixedly positioned in a respective channel port A-H of the header14(1). The cables12are not connected to the header14(1) in any particular order. Upon positioning each cable in the header14(1), the header14(1) is electrically connected to the conductive shielding of the cables12. More particularly, as described in greater detail with reference toFIGS. 2A-2G, the header14(1) has sixteen contacts that are each positioned within a respective channel port A-H of the header14(1). Each contact is associated with a respective cable12that is fixedly positioned in the header14(1). Each contact of the header14(1) either displaces or pierces the outer jacket of a respective cable12and contacts the conductive shielding of the respective cable12. The contacts of the header14(1) are electrically isolated from each other.

By virtue of the interconnection of cables12, header14(1), plug16, electrical tester18, and wires20, the cable12A is electrically connected to channel A of the electrical tester18, the cable12B is electrically connected to channel B of the electrical tester18, and so forth.

At step106, the electrical tester18transmits a signal through the shielding of one predetermined cable12that is connected to the header14(1).

At step108, the test probe22(e.g., an Alligator Clip) of the electrical tester18is then manually coupled one at a time to the second ends of the cables12(e.g., end12(A)(2) of cable12A) until the test probe22is coupled to the pre-determined cable which receives the signal that is transmitted by the electrical tester18at step106. It should be understood that the test probe22is not coupled to the cables12in any particular order, and the test probe22is connected to one cable at a time.

At step110, the electrical tester18alerts the operator that the cable end that is coupled to the test probe22is the pre-determined cable which receives the signal that is transmitted by the electrical tester18at step106. The electrical tester18is configured to make this determination based upon resistance, capacitance, voltage, signal frequency, signal waveform, or signal amplitude values, for example, transmitted through the cable. It should be understood that once the electrical tester18is electrically connected to both ends of the predetermined cable, a circuit is completed and an alert is triggered by the electrical tester18. For example, if a signal is applied to cable end12(A)(1) by the electrical tester18, then once the operator couples the test probe22to the cable end12(A)(2), the electrical tester18will alert the operator that the coupled cable is cable12A. The operator then knows which cable12A-12H of the cable bundle is coupled to the test probe22.

To alert the operator, the electrical tester18includes means for alerting (labeled A-H on the electrical tester18) that both ends of a particular cable12are electrically coupled to the electrical tester18, thereby completing a circuit. The means for alerting may be visual in the form of a light and/or audible in the form of a buzzer, for example.

At step112, the operator inserts the second end of the identified cable12into the proper channel port A-H on the other header14(2) based upon the known position of the first end of the predetermined cable in header14(1). For example, once cable end12(A)(2) of cable12A is identified as cable12A, the operator inserts the cable end12(A)(2) of cable12A into channel port A of the header14(2). Alternatively, the operator may insert the cable end12(A)(2) of cable12A into channel port H of the header14(2) to reverse-wire the headers14(1) and14(2), if so desired. This process is repeated (as indicated by the reverse arrow from step112to step106inFIG. 3) until all eight cables12A-12H of the cable bundle are identified and positioned in the other header14(2).

At step114, once the second end of all of the cables12have been positioned in their respective channel ports A-H on the other header14(2), the operator closes the header14(2) to fix the positions of the cables12A-12H in the header14(2). At step116, the plug16is disconnected from the header14(1), the cable assembly is installed into a fixture (not shown), and the ends of the cables are soldered together, as represented by item26inFIG. 1B. Soldering the ends of the cables permanently fixes the position of the cables12A-12H relative to each other. What remains is a cable assembly24including two headers14(1) and14(2) and the discrete cables12, as shown inFIG. 1B.

At step117, the cable assembly24is packaged and provided to an end user as a sub-assembly. Once received, the end user perform step118, which is described hereinafter. Step117is an optional step of this exemplary process.

At step118, the headers14(1) and14(2) are removed from the cable assembly24and the ends of the cables are stripped to expose the conductor and the shield of each cable12. Thereafter, both ends of the cable assembly (without the headers14) are mounted to one or more circuit boards by an end user or packaged and provided to an end-user as a sub-assembly.

The cable assembly24ofFIG. 1Bincludes a single group of cables, i.e., cables12A-12H. If the cable assembly includes multiple groups of cables, then the cable groups are identified prior to identifying the individual cables of each group. To identify the different cable groups, the groups of conductors may simply be distinguished at the time that the cable is created by using color coded cables, wrapping cable groups in colored tape or string, or staggering the cable groups, for example. If the coaxes are grouped at the time of cabling, then the identification process can proceed directly to step100ofFIG. 3. However, if the cable groupings are not identified at the time the cables are created, then additional steps are required, as described hereinafter.

FIG. 4depicts a schematic block diagram of a process for identifying individual coax cable groups in a bundle of coax cables according to still another aspect of the invention. It should be understood that, unlike the cable bundle ofFIG. 1A, the cable bundle described with reference toFIG. 4would include more than eight cables.

At step120, eight individual coax cables12A-12H are selected from the cable bundle at random and the first ends of those cables12A-12H are placed in the header14(1). The selected cables12A-12H represent the first group of cables.

At step121, the header14(1) is then mechanically and electrically connected to the plug16and the plug16is electrically connected to the electrical tester18as previously described. Step121may occur either before or after step120.

At step122, the electrical tester18transmits a signal through the shielding of each of the cables12A-12H of the first group of cables that is connected to the header14(1). At step123, the test probe22(e.g., an Alligator Clip) of the electrical tester18is manually coupled one at a time to the second ends of the cables in the cable bundle at random. At step124, the electrical tester18alerts the operator as to whether the particular cable that is coupled to the test probe22belongs to the first cable group12A-12H. The electrical tester18is configured to make this determination based upon resistance, capacitance, voltage, signal frequency, signal waveform, or signal amplitude values, for example, transmitted through the cables. Once identified as belonging to the first cable group, the individual cables of the first group are segregated from the remaining cable of the bundle and marked to distinguish the first group from the remaining groups.

This process is repeated for all of the cable groups, as indicated by the reverse arrow from step123to step120, until every cable of the cable bundle has been assigned to a cable group by the operator. Thereafter, the process returns to step104ofFIG. 3and the process ofFIG. 3continues as previously described so that the second end of every cable of every cable group is positioned in the proper channel port A-H of a header14. It should be understood that each cable group requires two headers, thus the first cable group utilizes headers14(1) and14(2), whereas the second cable group utilizes two different headers14(not shown).

Modifications may be made to the system10without departing from the scope or the spirit of the invention. For example, the plug16, electrical tester18, and wires20may be a pre-assembled unit.

Additionally, the plug16and the wires20are optional components of the system. For example, according to another exemplary embodiment of the invention, the header14is directly connected to the multi-channel electrical tester18(by pins and sockets, for example), and the plug16and wires20are omitted. According to yet another exemplary embodiment of the invention, the wires20are directly connected to both the header14and the electrical tester18, and the plug16is omitted.

The number of cables in the bundle may vary depending upon the particular application. The number of headers14may also vary. For example, two eight-position headers14maybe used to accommodate sixteen cables. It should be understood that the cables are not limited to coaxial cables, and may be any cable that is suited for any particular application.

FIGS. 2A-2Fdepict perspective, front elevation, top plan, bottom plan, side elevation and exploded views of a coax ribbonizing header50, according to one exemplary embodiment of the invention.FIG. 2Gis a cross-sectional view of the header50ofFIG. 2Btaken along the lines2G-2G. The header50is similar to the header14that was described with reference toFIGS. 1A and 1B, with the exception that header50accommodates sixteen cables whereas header14accommodates eight cables.

The header50generally comprises a top housing portion52that is releasably mounted to a bottom housing portion54. The housing portions52and54are releasably mated together by a clip53on the top portion52that engages a recess55formed on the bottom housing portion54. In a mated condition of the header50, a series of sixteen recesses or slots58are defined between semi-circular cutouts defined on respective housing portions52and54of the header50(seeFIG. 2B). The recesses58are sized to accommodate a cable (not shown) having a wire gauge range of 38-46 AWG.

A series of contacts56are positioned in recesses60that are defined through the thickness of the housing portion54of the header50. The header50includes sixteen contacts56, i.e., one contact56per recess58. As best shown inFIG. 2B, the sharp end of each contact56extends into its respective recess58of the header50by a distance that is sufficient to pierce the outer jacket and contact the conductive shield of a cable that is positioned in the respective recess58.

To assemble the cables into the header50, the cables are first positioned in the semi-circular channels of the housing portion54of the header. The housing portion52is mated to the housing portion54by snapping the clips53into respective recesses55. By mating the housing portions52and54together, each contact pierces the outer jacket and contacts the conductive shield of a cable that is positioned in a respective recess58. The cables are electrically isolated from each other because the contacts56are electrically isolated from each other.

Although not shown inFIGS. 2A-2G, the recesses60of the header50are sized to receive contacts on a plug that is similar to plug16ofFIG. 1A. Upon inserting the contacts on a plug into the recesses60of the header50, electrical contact is established between the plug and the individual channels of the header50. The contacts56may vary from that shown and described. For example, the contacts56may include a socket on the end that is opposite its sharp end for receiving a contact of the plug.

As noted above, the contacts56may vary from that shown and described.FIG. 2Hdepicts an exploded view of another coax ribbonizing header150, which includes different contacts than the coax ribbonizing header50ofFIGS. 2A-2F. Other than the contacts, the coax ribbonizing headers50and150are substantially the same. The contacts156of the coax ribbonizing header150are blade-style contacts. Each contact156includes a sharp v-shaped edge for either displacing or piercing the outer jacket of a respective cable12.