Abstract:
A coaxial jack has an electrically groundable housing including first and second ports, a printed circuit board supporting a terminating element and conductive traces, and a center conductor disposed within the electrically groundable housing. The center conductor extends through a hole in the printed circuit board and is normally coupled to the electrically groundable housing contact through the terminating element and the conductive traces. A grounding spring has a leaf spring that acts as switch to break the coupling when a plug is inserted into the first port.

Description:
TECHNICAL FIELD OF THE INVENTION  
       [0001]     The present invention relates to coaxial jacks and, for example, to high frequency single coaxial jacks.  
       BACKGROUND OF THE INVENTION  
       [0002]     Various types of coaxial jacks are well known. Such coaxial jacks generally include at least one center conductor disposed within a grounded electrically conductive housing to establish a signal path between first and second ports at opposing ends of the housing. The first port is arranged to receive a plug, and the second port is arranged to receive a connector. When no plug is inserted into the first port of the housing, the center conductor is typically terminated to ground through a terminating resistor. Thus, a connector in the second port is also terminated to ground. However, when a plug is inserted into the first port of the housing, the termination to ground is broken, allowing a signal to pass between a connector in the second port and the plug in the first port of the housing.  
         [0003]     Prior coaxial jacks have a number of problems. These coaxial jacks typically rely on complicated switches to control the termination of the center conductor. Such switches add to the cost and labor required to produce coaxial jacks. Also, the switches typically used in prior art coaxial jacks are unreliable.  
         [0004]     The jack of the present invention overcomes one or more of these or other problems.  
       SUMMARY OF THE INVENTION  
       [0005]     In accordance with an aspect of the present invention, a coaxial jack comprises an electrically groundable housing including first and second ports, a printed circuit board supporting conductive traces, and a center conductor that is disposed within the electrically groundable housing so as to extend through a hole in the printed circuit board and so as to contact at least one of the conductive traces.  
         [0006]     In accordance with another aspect of the present invention, a coaxial jack comprises an electrically groundable housing including first and second ports, a center conductor, and a grounding spring. The center conductor is disposed within the electrically groundable housing so as to extend through a hole in the printed circuit board and so as to contact at least one of the conductive traces. The grounding spring is within the first port and is arranged so that a plug received in the first port is received within the grounding spring. The grounding spring includes a contact to control signal flow between the first and second ports.  
         [0007]     In accordance with still another aspect of the present invention, a coaxial jack comprises an electrically groundable housing including first and second ports, a printed circuit board supporting a terminating element and conductive traces, and a center conductor that is disposed within the electrically groundable housing so as to extend through a hole in the printed circuit board and so as to be normally coupled to the electrically groundable housing contact through the terminating element and the conductive traces. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]     These and other features and advantages will become more apparent from a detailed consideration of the invention when taken in conjunction with the drawings in which:  
         [0009]      FIG. 1  is an isometric view of a jack according to one embodiment of the present invention;  
         [0010]      FIG. 2  is an exploded view of the jack of  FIG. 1 ;  
         [0011]      FIG. 3  is a cross sectional side view of the jack of  FIG. 1 ;  
         [0012]      FIG. 4  illustrates a detail of the jack as shown in  FIG. 3 ;  
         [0013]      FIG. 5  is a cross sectional side view of the jack of  FIG. 1  with a plug inserted into the jack;  
         [0014]      FIG. 6  illustrates a detail of the jack as shown in  FIG. 5 ;  
         [0015]      FIG. 7  is an isometric view of a printed circuit board used in the jack of  FIGS. 1-6 ; and,  
         [0016]      FIG. 8  is an isometric view of a patchbay having a plurality of jacks, such as shown in  FIGS. 1-6 , inserted therein. 
     
    
     DETAILED DESCRIPTION  
       [0017]     A single self-terminating jack  10  according to one embodiment of the present invention is shown in  FIGS. 1-7 . The single self-terminating jack  10  includes a conductive housing  12  having a first port  14  at a first end of the conductive housing  12  and a second port  16  at a second end of the conductive housing  12 . The first port  14  may be arranged to accept a plug such as a WECO plug, and the second port  16  may be arranged to accept a connector such as a BNC connector.  
         [0018]     A center conductor  18  extending between the first and second ports  14  and  16  is provided within the conductive housing  12 . The center conductor  18  is centered within the conductive housing  12  by an insulating member  20  and a printed circuit board  22 .  
         [0019]     As shown in  FIGS. 3 and 5 , the center conductor  18  extends through a center hole in the insulating member  20  to support one end of the center conductor  18  within the second port  16 . The outer perimeter of the insulating member  20  substantially matches the inner perimeter of the second port  16  so that the insulating member  20  centers its corresponding end of the center conductor  18  within the second port  16 . Although these perimeters may have any desired shapes, these perimeters may be relatively circular as shown in  FIGS. 1 and 2  such that the insulating member  20  may be in the form of an insulating disc. The center conductor  18 , when extending through the center hole of the insulating member  20 , may, for example, be substantially perpendicular to the insulating member  20 .  
         [0020]     The conductive housing  12  also includes a conductive grounding spring  24  which has an outer perimeter that substantially matches the inner perimeter of the first port  14 . As shown in  FIGS. 3-6 , the conductive grounding spring  24  butts up against the printed circuit board  22 . The outer perimeter of the printed circuit board  22  substantially matches the inner perimeter of the first port  14 , and the center conductor  18  extends through a center hole  26  of the printed circuit board  22 . Consequently, the conductive grounding spring  24  electrically engages the first port  14  of the conductive housing  12 , and the printed circuit board  22  centers its corresponding end of the center conductor  18  within the first port  14 . Again, although these perimeters may have any desired shapes, these perimeters may be relatively circular as shown in  FIGS. 1 and 2 .  
         [0021]     As shown in  FIG. 7 , the printed circuit board  22  includes an insulating board  28  having the center hole  26  extending there through to receive the center conductor  18 . The center conductor  18 , when extending through the center hole  26 , may, for example, be substantially perpendicular to insulating board  28 .  
         [0022]     The circular wall of the insulating board  28  that forms the center hole  26  has a conductive trace  30  extending there around. A terminating element  32  is supported on the insulating board  28 . The terminating element  32 , for example, may be a resistor. The insulating board  28  also supports conductive traces  34  and  36 . The terminating element  32 , for example, may be a 75Ω resistor.  
         [0023]     The conductive trace  34  has a first end that electrically engages a first end of the terminating element  32  and a second end that electrically engages the conductive trace  30 . The conductive trace  36  has a first end that electrically engages a second end of the terminating element  32  and a second end that electrically engages a conductive trace  38 . The conductive trace  38  is provided along a perimeter wall of the insulating board  28  that is formed by a recess  40 .  
         [0024]     As perhaps best shown in  FIGS. 2, 4 , and  6 , the conductive grounding spring  24  has a conductive leaf spring  42  that is of sufficient length to extend into the recess  40  of the printed circuit board  22 . As explained hereinafter, the leaf spring  42  may be a contact and/or may perform the function of a switch.  
         [0025]     With no plug inserted into the first port  14  of the single self-terminating jack  10  as shown in  FIGS. 3 and 4 , the conductive leaf spring  42  is pre-loaded to engage the conductive trace  38  on the printed circuit board  22 . Accordingly, an electrical circuit is established from the conductive housing  12  through the conductive grounding spring  24 , through the conductive leaf spring  42 , through the conductive trace  38 , through the conductive trace  36 , through the terminating element  32 , through the conductive trace  34 , through the conductive trace  30 , and to the center conductor  18 . Thus, with the conductive housing  12  coupled to ground, the center conductor  18  is coupled to ground through the terminating element  32  when no plug is inserted into the second port  16 , and any connector inserted into the second port  16  is also coupled to ground through the terminating element  32 .  
         [0026]     When a plug  50  is inserted into the first port  14  of the single self-terminating jack  10  as shown in  FIGS. 5 and 6 , the conductive leaf spring  42  is pushed away from the conductive trace  38  on the printed circuit board  22  by the plug  50 . Accordingly, the electrical circuit from the conductive housing  12  through the conductive grounding spring  24 , through the conductive leaf spring  42 , through the conductive trace  38 , through the conductive trace  36 , through the terminating element  32 , through the conductive trace  34 , through the conductive trace  30 , and to the center conductor  18  is broken. Thus, the center conductor  18  is no longer coupled to ground through the terminating element  32 , and instead a signal from a connector inserted into the second port  16  is coupled through the center conductor  18  to the plug  50 .  
         [0027]     As can be seen from  FIGS. 2, 5 , and  6 , the conductive grounding spring  24  is shaped so that the plug  50  is received within the conductive grounding spring  24  and so that the inside perimeter of the conductive grounding spring  24  substantially matches an outside perimeter of the plug  50 . Accordingly, the outer conductive sheath of the plug  50  is coupled to ground by the first port  14 .  
         [0028]     As shown in  FIG. 8 , a plurality of the single self-terminating jacks  10  are attached to a patchbay  60 . Each of these single self-terminating jacks  10  is attached to the patchbay  60  by use of a fastener  62 . The fastener  62 , for example, may be a screw that is inserted through a flange post  64  of the conductive housing  12  and is threaded into a corresponding hole in the patchbay  60 . As can be seen in  FIG. 8 , some of the single self-terminating jacks  10  are longer than others of the single self-terminating jacks  10 . This difference in length between adjacent ones of the single self-terminating jacks  10  may be provided to accommodate the size of the BNC connectors of the cables that are to be coupled to the patchbay  60 .  
         [0029]     Examples of materials that may be used for the single self-terminating jack  10  are described below in this paragraph. However, it should be understood that other materials could be used without departing from the scope of the present invention. Accordingly, the conductive housing  12  including the first and second ports  14  and  16  may comprise a brass alloy plated with nickel. The fastener  62  may comprise a steel alloy plated with zinc. The conductive grounding clip  26  may comprise beryllium copper finished with gold or nickel plating. The insulating member  20  may comprise PTFE. The insulating board  28  may comprise PCB-FR-4 having conducting conductive traces made of copper finished with gold over nickel plating. The center connector  18  may be beryllium copper finished with gold over nickel plating.  
         [0030]     Certain modifications of the present invention have been disclosed above. Other modifications will occur to those practicing in the art of the present invention. For example, the jack described above may come in a variety of sizes.  
         [0031]     Moreover, the jack described above may be used as an audio, a video, and/or other jack.  
         [0032]     Furthermore, as disclosed above, the terminating element  32  of the single self-terminating jack  10  is a resistor. Instead, one or more other passive and/or active devices may be used as the terminating element  32  in the single self-terminating jack  10 .  
         [0033]     Also, the present invention may be used in connection with jacks having more than two ports.  
         [0034]     Additionally, the first and second ports  14  and  16  are shown in  FIG. 2  as separate elements that make up the conductive housing  12 . Instead, the first and second ports  14  and  16  may be integrally formed as the conductive housing  12  so that the conductive housing  12  is a single continuous member.  
         [0035]     Accordingly, the description of the present invention is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the best mode of carrying out the invention. The details may be varied substantially without departing from the spirit of the invention, and the exclusive use of all modifications which are within the scope of the appended claims is reserved.