Abstract:
Methods and apparatus for discharging cables that are to be coupled to a connector are disclosed. According to one aspect of the present invention, an apparatus includes at least one signal contact, a housing, and a ground arrangement. The housing defines a receptacle configured to receive a part of a cable assembly. The signal contact is disposed within the receptacle, and is configured to contact a first contact of the cable assembly when the cable assembly is received in the receptacle such that a signal may pass between the signal contact and the first contact. The ground arrangement is at least partially disposed on the housing, and is arranged to contact and to ground the first contact before the first contact contacts the at least one signal contact.

Description:
BACKGROUND OF THE INVENTION 
   The connection of cables to ports on electronic equipment, e.g., network equipment, often causes electrostatic discharge (ESD) events. An ESD event is generally a flow of an electric current from one potential to another that may damage electronic equipment. To prevent ESD events, persons handling cables may take precautions such as wearing conductive wrist straps and working in electrostatic protective areas. However, even with the proper handling of cables, electron accumulation often occurs on the cables and, hence, ESD events occur when the cables are plugged into ports on electronic equipment. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention may best be understood by reference to the following description taken in conjunction with the accompanying drawings in which: 
       FIG. 1  is a diagrammatic representation of a modified RJ connector in accordance with an embodiment of the present invention. 
       FIG. 2A  is a block diagram representation of an RJ connector assembly into which a cable may be plugged in accordance with an embodiment of the present invention. 
       FIG. 2B  is a block diagram representation of a cable in contact with ground conductors in an RJ connector assembly, e.g., ground conductors  204  of RJ connector assembly  200  of  FIG. 2A , in accordance with an embodiment of the present invention. 
       FIG. 2C  is a block diagram representation of a cable seated in an RJ connector assembly, e.g., RJ connector assembly  200  of  FIG. 2A , in accordance with an embodiment of the present invention. 
       FIG. 3  is a process flow diagram which illustrates one method of plugging a cable into an RJ connector assembly that includes ground conductors in accordance with an embodiment of the present invention. 
       FIG. 4A  is a block diagram representation of an RJ connector assembly which includes an adapter with ground conductors in accordance with an embodiment of the present invention. 
       FIG. 4B  is a block diagram representation of an adapter with ground conductors, e.g., adapter  420  of  FIG. 4A  in accordance with an embodiment of the present invention. 
       FIG. 5  is a diagrammatic representation of an RJ connector assembly that includes an adapter with ground conductors in accordance with an embodiment of the present invention. 
   

   DESCRIPTION OF EXAMPLE EMBODIMENTS 
   General Overview 
   In one embodiment, an apparatus includes at least one signal contact, a housing, and a ground arrangement. The housing defines a receptacle configured to receive a part of a cable assembly. The signal contact is disposed within the receptacle, and is configured to contact a first contact of the cable assembly when the cable assembly is received in the receptacle such that a signal may pass between the signal contact and the first contact. The ground arrangement is at least partially disposed on the housing, and is arranged to contact and to ground the first contact before the first contact contacts the at least one signal contact. 
   DESCRIPTION 
   RJ connectors are often used to connect or otherwise terminate cables that are used in telecommunications applications. RJ style connectors may include, but are not limited to, RJ-11, RJ-21, and RJ-45 connectors. A modified RJ connector or an overall RJ connector assembly that includes ground conductors that make contact with the contacts of a cable prior to the cable being seated within the connector assembly, i.e., such that the contacts of the cable are interfaced with contacts of the connector assembly. When a cable makes contact with the ground conductors of the connector assembly, substantially any electron build-up in the cable may be discharged through the ground conductors. That is, the ground conductors provide a grounding path for any charge that is accumulated in the cable that would otherwise potentially cause an electrostatic discharge (ESD) event with respect to the contacts of the connector assembly. Hence, when the cable or, more specifically, the contacts of the cable come into contact with the contacts of the connector assembly, the risk of an ESD event occurring is relatively low. 
   With reference to  FIG. 1 , one example of an RJ connector with ground conductors will be described in accordance with an embodiment of the present invention. An RJ connector  100  includes a housing  102  and electrical contacts  108 . Housing  102  is generally a shell into which a cable (not shown) may be received and held. That is, housing  102  defines a receptacle or a receiver for a cable (not shown). When a cable (not shown) is held within housing  102 , electrical contacts of the cable are positioned in contact with a plurality of contacts  108 , e.g., an array of contacts, disposed in housing  102  such that streams or signals may flow between the electrical contacts of the cable and contacts  108 . Typically, contacts  108  are communicably coupled to elements or components of an electronic device for which connector  100  serves as a port. By way of example, contacts  108  may be coupled to wires and/or leads which connect to devices on a printed circuit board or a line card on which connector  100  is supported. 
   Connector  100  also includes ground conductors  104  which are positioned at an entrance to connector  100  or, more specifically, the entrance to a receptacle defined by housing  102 . In other words, ground conductors  104  are positioned such that a electrical contacts of a cable (not shown) that is being plugged into connector  100  will come into contact with ground conductors  104  prior to coming into contact with contacts  108 . In one embodiment, ground conductors  104  are positioned at a front edge of housing  102  and sized such that connector  100  has substantially the same footprint as a standard connector  100 . By way of example, if connector  100  is an RJ-11 connector, then connector  100  has substantially the same external dimensions as a standard RJ-11 connector. 
   Ground conductors  104 , or ESD contacts, may be metallized and relatively flexible. By way of example, ground conductors  104  may be arranged such that when a force is imparted on ground conductors  104  in a z-direction  114  by electrical contacts of a cable (not shown), ground conductors  104  may slightly deform, and provide a restraining force in z-direction  114  that substantially counteracts the force applied by the cable. The flexibility of ground conductors  104  effectively ensures that ground conductors  104  will contact recessed electrical contacts of a cable (not shown) during the insertion of the cable into housing  100 , and allow for the cable to be seated within housing  100  once insertion is complete. 
   Ground conductors  104  are coupled to a chassis (not shown) via ground pins  112 . That is, ground conductors  104  are in communication with a grounding shield (not shown) of connector  100  that is coupled to a grounded chassis (not shown) through pins  112 . Such a shield (not shown) is effectively referenced to a chassis (not shown). A path defined from ground conductors  104  through the shield (not shown) to the chassis (not shown) is effectively a grounding path that allows any electrical discharge to end at a grounded chassis. As will be appreciated by those skilled in the art, electrical charge may be stored up due to handling and dragging of a cable assembly (not shown) that is to be plugged into connector  100 . As such, the path to ground allows electrical discharge to substantially be controlled by reducing the likelihood that any electrical discharge will occur through contacts  108 . 
     FIG. 2A  is a block diagram of a cable and a connector assembly that includes ground conductors in accordance with an embodiment of the present invention. A connector assembly  200  is arranged to receive a cable  216  that includes contacts  220 . Connector assembly  200  includes ground conductors  204  that are arranged to allow for an ESD event to occur, and contacts  208  that are arranged to substantially engage with contacts  220  when a head-end of cable  216  is positioned within assembly  220 . When an insertion of cable  216  into connector assembly  200  begins, contacts  220  of cable  216  come into contact with ground conductors  204  of connector assembly  200 , as shown in  FIG. 2B . As ground conductors  204  provide a controlled return path to a grounded chassis, electrical charge that is built up in cable  216  may be discharged to ground upon contact of contacts  220  with ground conductors  204 . 
   Upon further insertion of cable  216  into connector assembly  200 , when contacts  220  of cable  216  engage with contacts  208  of connector assembly  220 , an ESD event is not likely to occur, as substantially any stored charge has already been discharged to ground by ground conductors  204 . Hence, as shown in  FIG. 2C , when cable  216  is inserted in connector assembly  200 , the likelihood of an ESD event occurring is relatively low. 
   Referring next to  FIG. 3 , the steps associated with one method of inserting a cable into a connector assembly that includes ground conductors will be described in accordance with an embodiment of the present invention. A process  301  of inserting a cable into a connector assembly begins at step  305  in which contacts on a cable assembly contact ground conductors on the connector assembly. Once the contacts on the cable assembly come into contact with the ground conductors on the connector assembly, if there is stored up electrical charge on the cable assembly, an ESD event may occur such that the electrical charge is discharged through a controlled return path to a ground of a chassis in step  309 . 
   After the ESD event, if any, occurs, the contacts on the cable assembly come into contact with the contacts on the connector assembly in step  313 . In one embodiment, when the contacts on the cable assembly contact or engage the contacts on the connector assembly, the connector assembly is effectively mated with the cable assembly. The process of inserting the cable assembly into the connector assembly is completed when the contacts on the cable assembly contact the contacts on the connector assembly. 
   In general, an RJ connector assembly has been described as a modified connector, e.g., a modified connector port or jack, that substantially integrally includes ground conductors. A modified RJ connector generally has substantially the same footprint as a standard RJ connector. Hence, a modified RJ connector with ground conductors may be used to retrofit substantially any equipment which uses a standard, e.g., shielded, RJ connector. As such, the use of a modified RJ connector does not utilize more space within the equipment than used by a standard connector. 
   In lieu of being a modified RJ connector, however, an RJ connector assembly may include a standard RJ connector that is interfaced with an adapter that includes ground conductors. That is, an RJ connector assembly may effectively be formed by augmenting a standard RJ connector with an adapter. Such an adapter may be used to provide a standard RJ connector, as for example a standard RJ connector that is already installed in electronic equipment, with ESD protection. 
     FIG. 4A  is a block diagram representation of an RJ connector assembly which is comprised of a standard RJ connector and an adapter with ground conductors in accordance with an embodiment of the present invention. A connector assembly  400  includes a standard connector  402 , e.g., an RJ connector without integral ground conductors, and an adapter  420  that includes ground conductors  404 . When standard connector  402  and adapter  420  are coupled or otherwise interfaced, ground conductors  404  are coupled to a ground connection  412  in standard connector  402 . As ground connection  412  is coupled to a grounded chassis (not shown), ground conductors  404  are effectively coupled to the grounded chassis through ground connection  412 . Hence, when a cable assembly (not shown) comes into contact with ground conductors  404 , any charges stored up in the cable assembly may be discharged to the grounded chassis (not shown). 
   Adapter  420  generally includes a receptacle that allows a cable assembly (not shown) to be passed therethrough, and a coupler that allows adapter  420  to be coupled to standard connector  402 .  FIG. 4B  is a block diagram representation of adapter  420  in accordance with an embodiment of the present invention. In addition to ground conductors  404 , adapter  420  includes a cable receiver  424  that is arranged to receive a cable assembly. Cable receiver  424  may be, in one embodiment, an opening in adapter  420  that allows a cable to be inserted into standard connector  402  through cable receiver  424 . Adapter  420  also includes a coupler  428  that allows adapter  420  to be coupled to standard connector  402 . The configuration of coupler  428  may vary widely. By way of example, coupler  428  may effectively be a female end that is arranged to be coupled to standard connector  402 , which may serve as a male end. Alternatively, coupler  428  may be an adhesive that is arranged to adhere to standard connector  402 . 
   With reference to  FIG. 5 , one embodiment of an RJ connector assembly which includes an adapter will be described. A connector assembly  500  includes a standard connector  502  which includes contacts  508  and ground pins  512  that allow a shield (not shown) in standard connector  502  to be coupled to a grounded chassis (not shown). An adapter  520  of connector assembly  500  includes ground connectors  504 , and is arranged to be interfaced with standard connector  502 . Adapter  520  is configured to receive a cable (not shown) such that electrical contacts of the cable come into contact with ground conductors  504  prior to coming into contact with contacts  508 . 
   Although only a few embodiments of the present invention have been described, it should be understood that the present invention may be embodied in many other specific forms without departing from the spirit or the scope of the present invention. By way of example, the use of ground conductors to effectively prevent ESD events has been described as suitable in RJ style connectors. However, the use of ground conductors is not limited to use with RJ style connectors. Other connectors, such as other modular connectors that are used in telecommunications applications, may also utilize ground conductors. Such modular connectors may include, but are not limited to including, cable jacks such as CAT style cable jacks. 
   The number of grounding conductors in a connector assembly may vary widely depending upon the requirements of the connector assembly and the configuration of the grounding conductors. Additionally, the configuration of grounding conductors themselves may vary widely. For instance, as previously mentioned, a brush arrangement may be used as grounding conductors. 
   Grounding conductors have generally been described as an array of metallized conductors. The configuration of grounding conductors, however, may vary widely. For example, grounding conductors may include a conductive brush that contacts a cable when the cable is being plugged into a connector. In general, a grounding element that is arranged to prevent ESD events may be substantially any element of an RJ connector assembly that makes contact with electrical contacts of a cable before the cable is seated within the connector assembly without departing from the spirit or the scope of the present invention. 
   Further, grounding conductors or discharge contacts may be integrated into a connector shell design. That is, instead of being referenced to a grounding shield of a connector, grounding conductors may instead be integrally formed as a part of a grounding shield of the connector. For instance, a grounding shield may be formed such that the grounding shield itself comes into substantially direct contact with the contacts of a cable assembly to provide a ground path for ESD. 
   It should be appreciated that although a process of inserting a cable assembly into a connector has generally been described as including an ESD event, a process of disengaging or otherwise unmating a cable assembly from a connector may also include an ESD event. In other words, while ground conductors on a connector allow contacts of a cable assembly to discharge accumulated charge upon insertion of the cable assembly into the connector, such ground conductors may also allow accumulated charge on the cable assembly to be discharge upon removing the cable assembly from the connector. 
   The steps associated with the methods of the present invention may vary widely. Steps may be added, removed, altered, combined, and reordered without departing from the spirit of the scope of the present invention. Therefore, the present examples are to be considered as illustrative and not restrictive, and the invention is not to be limited to the details given herein, but may be modified within the scope of the appended claims.