Interconnections for axial cables

Cable interconnection terminated by a pin or socket includes a housing, an inner conductor arranged in the housing and having a first end adapted to couple to the pin or socket, and an outer sheath adapted to couple to an outer sheath of a cable including at least one conductor, e.g., a coaxial cable, twin-axial cable or tri-axial cable. The interconnection also includes first and second pins. The first pin is arranged at a second end of the inner conductor while the second pin is electrically connected to the outer sheath. The first and second pins each have a mating portion, and both mating portions terminate at a common plane a set distance from the housing. This termination in a common plane, substantially perpendicular to the axial direction of the pins, enables the cable to mate with a wide range of electronic componentry.

FIELD OF THE INVENTION

The present invention relates generally to terminations for mating a coaxial contact to a discrete header style contact system on, for example, a test station.

BACKGROUND OF THE INVENTION

Patch panels or mass interconnect systems are typically utilized within test stations to permit easy connection and disconnection of a plurality of discrete analog, digital, power, fiber optic (FO) and radio frequency (RF) signals. Coaxial cables are generally used where wide bandwidth and shielding are required. More often than not, coaxial contacts for use within a patch panel are tailored for a select cable group or even a single specific type of coaxial cable. Users that require a different termination style on the mating side of the patch panel are left with few options to utilize different coaxial cables or transition to a different termination style. Current solutions that offer alternative termination options utilize termination styles that are not conducive to mating with industry standard 0.100″ pitch spacing and have asymmetrical pin lengths relative to the body of the contact.

One solution that provides an alternative termination for a coaxial cable is sold by Virginia Panel Corporation, designated product no, 61014140. This coax assembly100is shown inFIG. 4and includes an inner conductor102having a first end104that receives the center pin of a coaxial cable and a second end106defining a first, elongate contact. An intermediate sheath108surrounds the inner conductor102, except for a contact portion of the first, elongate contact defined at the second end106. The shield of the coaxial cable engages with an outer sheath110that is electrically connected to a second, elongate contact112. The first and second contacts are axially separated from one another by a distance of about 0.08 inches from center to center, but their axial ends are spaced apart from one another such that they cannot engage with a co-planar set of mating contacts.

OBJECTS AND SUMMARY OF THE INVENTION

An object of at least one embodiment of the present invention is to adapt a coaxial patch panel termination to a 0.100″ header style termination with 0.025″ square or round pins to allow a broader range of interconnect options.

To achieve this object, and possibly others, a cable interconnection terminated by a pin or socket in accordance with the invention includes a housing, an inner conductor at least partly arranged in the housing and having a first end adapted to couple to the pin or socket terminating a cable including at least one axial conductor (e.g., a coaxial, twin-axial or tri-axial cable) and a second end, and an outer sheath adapted to couple to an outer sheath of the cable. The interconnection also includes first and second pins. The first pin is arranged at a second end of the inner conductor while the second pin is electrically connected to the outer sheath. The first and second pins each have a mating portion, and both mating portions terminate at a common plane a set distance from the housing. This termination in a common plane, substantially perpendicular to the axial direction of the pins, enables the cable to mate with a wide range of electronic componentry.

In some embodiments, the first pin may be integral with the inner conductor. The mating portions of the first and second pins are spaced apart a distance of about 0.100 inches from another. The first and second pins may be round pins and the mating portions of the first and second pins have a diameter of about 0.025 inches. Alternatively, the first and second pins may be square pins and the mating portions of the first and second pins have a side of about 0.025 inches. The first and second pins extend from a common plane at a rear of the housing, this plane being parallel to the plane in which the ends of the pins are situated, and also substantially perpendicular to the axial direction of the pins. The first and second pins each have an angled portion between the mating portion and the housing that changes an axial direction of the pin, i.e., provides the pins with an axial offset. Electrical insulating material may be arranged in the housing between the inner conductor and the outer sheath. A spring retaining clip may be provided to retain the housing in a module.

A module in accordance with the invention includes a plurality of interconnections as described above. An indexing ridge may be arranged on each interconnection to provide alignment of the interconnections within the module.

The invention will be described in detail with reference to some preferred embodiments of the invention illustrated in the figures in the accompanying drawings. However, the invention is not confined to the illustrated and described embodiments alone.

DETAILED DESCRIPTION OF THE INVENTION

Carefully selected pieces of automatic test equipment (ATE) that are implemented in benchtop or transportable platforms form powerful test stations that are reconfigurable through the use of patch panels for interconnection. The patch panel interconnection allows mass connection and disconnection of discrete analog, digital, power, fiber optic (FO) and radio frequency (RF) signals. Connectors that utilize 0.100″ on-center pin spacing have been in use for decades and are commonly used for discrete analog and digital signals. Coaxial, twin-axial and tri-axial cabling is typically used for signals requiring low insertion loss, controlled impedance and shielding. For certain applications, it would be desirable to utilize the 0.100″ header style termination for a coaxial, twin-axial or tri-axial signal in lieu of the standard solder or crimp style termination.

The current invention permits the use of a 0.100″ header style termination in conjunction with a coaxial, twin-axial or tri-axial style contact. Preferred embodiments of the invention will be described with reference toFIGS. 1 and 2wherein like reference numerals refer to the same or similar elements.

Patch panel contacts are typically configured in a socket and pin arrangement where the socket contact normally is used on the equipment side of the patch panel and the pin contact is used on the test side of the patch panel. Other variations of contacts are implemented in a sexless manner whereby the contact mates with the same style contact and is used on both the equipment and test sides of the patch panel.

FIG. 1shows a side view of a pin contact10mated to a socket contact20in accordance with the invention. In this embodiment, the socket contact20includes a unique header configuration in accordance with the invention, while the pin contact10provides the termination for a coaxial cable. The reverse is also considered the invention, i.e., pin contact10is provided with the header configuration in accordance with the invention while the socket contact is used to terminate the coaxial cable. Indeed, it is also possible that the coaxial cable termination is neither a pin or socket style termination, but another type of coaxial cable termination, e.g., a sexless contact. Its mating contact would then be the component of a coaxial cable terminating assembly in accordance with the invention that includes the unique header configuration in accordance with the invention. One skilled in the art would recognize the manner in which to implement the unique header configuration for a sexless contact in view of the disclosure herein.

A plurality of contacts is typically installed within a module30(containing a plurality of pin contacts in this example) or module40(containing a plurality of socket contacts in this example) which permits for mass connection when engaged (mated). In cases where a sexless contact is implemented or where the pin contact and socket contact have compatible geometries, modules30and40could be populated with the same part. For modules that contain signal carrying contacts, this module is typically constructed from some form of insulating material, such as a polymer-based plastic. Additional details about such modules, and how to form such modules from pin contacts or socket contacts, or sexless contacts, are known to those skilled in the art to which this invention pertains, and would be readily apparent for use in the invention in view of the disclosure herein. One skilled in the art could therefore construct modules30and module40using their knowledge and the disclosure herein.

A respective spring retaining clip12allows each of the pin and socket contacts10,20to remain firmly mounted within the respective module housing30,40, during engagement/disengagement cycles. The spring retaining clip12is typically constructed from beryllium copper for its spring-like properties and plated with a thin layer of nickel for corrosion resistance. In a preferred embodiment, a separate extraction tool may be used to compress the spring retaining clips12of a contact10,20after mounting within the respective module30,40to allow for removal of the contact from the module. Instead of spring retaining clips12, other means or mechanism to mount the pin and socket contacts10,20within the respective module housing30,40may be used in the invention, and different mounting means and mechanism may be used for the pin and socket contacts10,20and within the same housing30,40. Such means and mechanism are known to those skilled in the art to which this invention pertains, and such means and mechanisms are considered for possible use in the invention.

Other types of patch panel modules may support functions such as vacuum or pneumatic applications which can be interspersed among different types of signal carrying modules. The manner in which these functions may be incorporated into the invention would be readily apparent to those skilled in the art to which this invention pertains in view of the disclosure herein.

Typical coaxial contacts have either a solder cup or crimp style termination14as a means for securing the pin contact10, to the coaxial, twin-axial or tri-axial cable8. Such cables will be referred to as a cable with at least one conductor. The termination14is situated over the coaxial cable8and may be considered part of the coaxial cable8. The coaxial cable8is typically stripped such that the overall jacket (sheath) is removed, exposing the shield (can be a braid, foil or both), the inner dielectric and the center conductor (seeFIG. 3). The center contact pin (typically supplied loose) is either crimped or soldered onto the center conductor, or otherwise brought into electrical contact therewith. The stripped cable, with the center conductor contact attached, is then inserted into the body of the coaxial contact. The contact body is then crimped over the cable. Each contact is different such that some crimp over the shield portion, some crimp over the overall jacket, and some get crimped twice, once over the shield portion and once over the jacket.

This style of termination may optionally include a ferrule (not shown) for fastening and reinforcing the connection of the coaxial cable8to the body of the pin contact10. The ferrule would be inserted onto the coaxial cable after the contact pin is electrically engaged with the center conductor and before the contact body is crimped over the cable. The ferrule can thus be slid over the braid and crimped with a crimping tool. Similarly, the other crimpings mentioned herein may be performed with a crimping tool known to those skilled in the art to which this invention pertains.

The body of the pin contact10is generally cylindrical in nature and typically constructed from brass, and plated with nickel for corrosion resistance and gold to improve its electrical properties. The pin contact10includes a tubular outer shield or sheath44, a tubular form of insulating material16inward of the outer shield or sheath44, and a center conductor42inward of the insulating material16(seeFIG. 2). The spring retaining clips12engage with the outer shield or sheath44. Center conductor42includes the structure for mating to a contact of the coaxial cable8, e.g., a receptacle or socket for mating to the center conductor of the coaxial cable8.

The socket contact20is shown with 0.025″ square header style pins22that are typically associated with about 0.100″ pin spacing. Pins22are dimensioned to terminate at ends that lie in a common plane a set distance from the housing of the socket contact20. The common plane may be substantially parallel to the rear edge of the housing of the socket contact20. The rear edge of the housing of the socket contact20may be planar, i.e., lie generally in a single vertical plane relative to the orientation shown inFIGS. 1 and 2. Thus, the pins22would terminate at ends that lie in the same vertical plane a set distance from the rear planar edge of the housing of the socket contact20. This allows the socket contact20to be engaged with mating contacts in a common plane. To achieve this, an inner conductor28at least partly arranged in the housing of the socket contact20has an aperture32at one end for receiving a pin of the pin contact10that terminates the coaxial cable8, and terminates in an about 0.025″ square header style pin,22at the opposing end of the inner conductor28(seeFIG. 2). The inner conductor28may be an integral unit or assembly with a central one of the pins22. Alternatively, the end of the inner conductor28would include a pin that enters into a socket of the coaxial cable termination.

It should be understood that the termination of the ends of the pins22in a common plane is the intended and preferred embodiment of the invention, but it is recognized there may be slight deviations in the commonality of this termination plane that arise, for example, from manufacturing conditions. Such deviations are unlikely to affect the ability to terminate the pins22to the mating contacts in the common plane. Moreover, in the illustrated embodiment, it should be noted that the termination plane is perpendicular to the longitudinal axis of the socket contact20. Thus, both pins22extend longitudinally a set, and the same distance, from the rear edge of the housing of the socket contact20.

The other, outer pin22is connected to an outer sheath36of the socket contact20. An electrical insulation component or member38is situated in the housing of the socket contact20between the inner conductor28and the outer sheath36. The housing of the socket contact20therefore includes, from the outermost component inward, an outer sheath36, insulation component or member38or other electrical insulating material, and inner conductor28. Optionally, an indexing ridge24described below is situated on the outer surface of the outer sheath36.

An alternate embodiment may utilize about 0.025″ diameter round pins in lieu of the square pin. In order to maintain spacing and form/fit with existing modules, the about 0.025″ pins must be formed in such a way to introduce an offset such that both pins22are approximately centered along the bore of the contact20. That is, the pins22are each spaced apart from the center axis extending between the pin and socket contacts10,20an equal distance. The header style pins22permit interfacing with cabling systems that adapt a single header pair of pins22to coaxial cabling. These cabling systems also employ carriers which permit a plurality of the header pairs to be grouped as a single connector to facilitate better cable management. The header style pins22also permit connection via wire wrap methods or even connection to a printed circuit board (PCB).

Regardless of which style pins22are used, it is important that at least a mating portion of each pin22has the designed shape and dimension, i.e., the entire pin is not necessary round or square but only a mating portion thereof that is needed for the pins22to mate with the cabling system. Each pin22also includes a bent or angled portion that changes the plane from which the pins22extend from the contact20, i.e., between the mating portion of the pins22and the housing of the socket contact20. The central one of the pins22extends from an approximately central location of the socket contact20and then is angled by the angled portion upward and then returns to a plane substantially parallel to the socket contact20(seeFIG. 3). Similarly, the outer one of the pins22extends from an outer region of the socket contact20and then is angled by the angled portion upward and then returns to a plane substantially parallel to the socket contact20(seeFIG. 3). The mating portions of the pins22are therefore substantially parallel to one another, i.e., rearward of the angled portions. The mating portions22are thus spaced apart from one another a predetermined distance, the purpose of which is explained below.

The pins22also preferably have symmetric pin lengths relative to the contact body, i.e., they terminate in a common vertical plane when viewed as shown inFIG. 3. This common vertical plane is substantially perpendicular to the axial direction of the pins. As a result of this termination, the pins22will generally also have a common length, i.e., both extend from the rear surface of the housing of the socket contact20the same distance. However, the pins22also start in a common plane, i.e., the plane at the rear of the housing of the socket contact20.

In a preferred embodiment the header style socket contact20is equipped with an indexing ridge24which allows for coherent alignment of all contacts within a module40(seeFIG. 3). It should also be noted that the about 0.100″ header style pins can be implemented in pin, socket or sexless types of coaxial contacts.

FIG. 2shows a cross-sectional view of the mated pin contact10and socket contact20and shows the spring retainer clip12mounting within the modules30,40in greater detail. A dielectric insulating material16(in pin contact10) or26(in socket contact20), is typically constructed from polytetrafluoroethylene (PTFE, more commonly known by the trademark name, TEFLON®) supports the center conductor42,28of the coaxial contact10,20, respectively, while insulating it from the surrounding body (shield or outer sheaths44,36). Each center conductor42,28is typically constructed from the same material as the body, in this case, brass with gold over nickel plating.

The geometries of the contact are such that the characteristic impedance of the coaxial contact is nominally 50 ohms which are common to RF applications.

Alternate embodiments may include geometries that result in a nominal 75 ohm characteristic impedance for video applications, or others still for twin-axial, tri-axial and custom applications.

In summary, the invention provides a termination for a coaxial contact, whether a pin contact or a socket contact, to a header style contact system adapted to mate with a pair of pins spaced apart from one another by a distance of, preferably, about 0.100 inches. The header configuration provides this pin spacing, i.e., pins22. Pins22preferably have a diameter when round or side when square of about 0.025 inches. Similar contacts to coaxial contacts are known for twin-axial and tri-axial cables, and the invention is equally applicable to such contacts as well.

Having thus described a few particular embodiments of the invention, various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications and improvements as are made obvious by this disclosure are intended to be part of this description though not expressly stated herein, and are intended to be within the spirit and scope of the invention. Accordingly, the foregoing description is by way of example only, and is not limiting. The invention is limited only as defined in the claims and equivalents thereto.