Patent Publication Number: US-6340306-B1

Title: Bridge clip for a connector

Description:
FIELD OF THE INVENTION 
     This invention relates to the field of telephone wire connector blocks and distribution systems, and specifically to a connector and a test device for testing wiring connected to the connector. 
     BACKGROUND OF INVENTION 
     In a telephone network, a network cable from the central office is connected to a building entrance protector (BEP) located at the customer site, where the individual telephone lines are broken out line-by-line. The network cable, which consist of a plurality of tip-ring wire pairs that each represent a telephone line, is typically connected to a connector block that forms a part of the BEP. Such connectors may be, for example, mini rocker tool-less insulation displacement (IDC)-type connectors, such as, for example, those sold by A. C. Egerton, Ltd. Other connectors used for telephony wiring applications are described in U.S. Pat. No. 4,662,699 to Vachhani et al., dated May 5, 1987, and in U.S. Pat. No. 3,611,264 to Ellis, dated Oct. 5, 1971. 
     The customer telephone equipment is coupled through such an IDC connector to, for example, a central office telephone line. The connector generally has a top section that includes two wire insertion holes and a bottom section that houses a pair of terminal strips. The wire insertion holes each accommodate one wire of a tip-ring wire pair. The top section pivots about a generally hinged fixed axis located on the side opposite the wire insertion holes and has a movable clasp for maintaining the top section in its closed position. 
     To open the top section, a user releases the clasp member and pivots the top section to its open position. When the top section is in its open position, the terminal strips do not intersect the wire insertion holes, but when the top section is in its closed position, the terminal strips intersect the wire insertion holes. Therefore, to establish an electrical and mechanical 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 brought into electrical and mechanical contact with the terminal strips. To remove the wires and/or break the electrical connection, the process is reversed. 
     To verify the integrity of a telephone line, the telephone line may be tested at the connector using a bridge clip. The bridge clip includes a body, at least a first test prong and a second test prong connected to the body, and lead wires for connecting the first and second test prongs to a testing device, such as a volt meter or telephone test set. The bottom section of the connector includes two channels, each located adjacent a terminal strip and sized to accommodate a test prong of a bridge clip. The test prongs are spaced apart and constructed to be received within the channels. 
     Testing is typically performed by inserting the test prongs of a bridge clip into the channels of the bottom section of the connector until each of the test prongs contacts an outside edge of one of the pair of terminal strips housed within the bottom section to make an electrical connection. If a current flow is detected, or a dial tone is heard, depending on the test methodology, then a loop condition exists for that particular tip-ring wire pair, and the integrity of the line is verified. If no loop condition is found, either an electrical open or short exists in telephone line or a connection to or in the terminal block is defective. 
     The prior art connector has no means of reliably maintaining a secure connection between the bridge clip test prongs and the terminal strips of the connector. Prior art test prongs typically consist of flexible metallic strips that are bent inwardly so as to bias the portion of the prong that contacts the terminal strip against the terminal strip. Such a connection is not reliable, however, as the prongs of the bridge clip are permitted to move within the channel. As such, when the user inserts the bridge clip and performs the test with the testing device, the user must affirmatively hold the bridge clip to the connector so that the electrical connection is secure. Otherwise, any movement of the bridge clip can cause the testing prongs to break the electrical connection with the terminal strips, thereby causing a false test reading. Further, after repeated use, one or both of the testing prongs can bend outwardly thereby causing unreliable connections. 
     In addition, the prior art connector testing systems do not prevent the user from inadvertently overinserting the bridge clip test leads to a position where the test leads cause damage to the connector. Nor do prior art connector testing systems provide a discernible signal to the user when the bridge clip makes an electrical connection to the bridge clip. 
     SUMMARY OF THE INVENTION 
     The present invention is directed at overcoming shortcomings in the prior art. A connector testing system in accordance with the present invention preferably includes a connector, an electrically conductive terminal strip disposed within the connector, a bridge clip preferably having a body and a first test lead connected thereto, and a latch movable between a first position wherein the bridge clip is secured to the connector, and a second position wherein the bridge clip is not secured to the connector. In this manner, the testing system provides a reliable contact between the bridge clip and the terminal strips of the connector during testing procedures. 
     The connector testing system preferably includes a connector, a terminal strip disposed within the connector and having a receptacle. In addition, a bridge clip for testing electrical connections is provided that includes a body and at least one test lead having a first end connected to the body, and a second end having a dimple formed thereon. The receptacle can be sized and constructed to receive the dimple when the second end of the test lead is inserted into the side fold, so prevent overinsertion of the test lead into the connector. 
     In a second embodiment, a bridge clip includes a body, a test lead connected to the body having a free end, and a latch formed with the body, the latch including a first deflection beam formed on one side of the body and a second deflection beam formed on an opposite side of the body. 
     Other objects and features of the present invention will become apparent from the following detailed description, considered in conjunction with the accompanying drawing figures. It is to be understood, however, that the drawings, which are not to scale, are designed solely for the purpose of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the drawing figures, which are not to scale, and which are merely illustrative, and wherein like reference numerals depict like elements throughout the several views: 
     FIG. 1 is a front elevational view of a terminal strip of a connector constructed in accordance with the present invention; 
     FIG. 2 is a top plan view of the terminal strip of FIG. 1; 
     FIG. 3 is a left-side elevational view of the terminal strip of FIG. 1; 
     FIG. 4 is a front elevational view of a bridge clip constructed in accordance with the present invention; 
     FIG. 5 is a side elevational view of the bridge clip of FIG. 4; 
     FIGS. 6A and 6B are front elevational cross-sectional views of the bridge clip being inserted into the connector ( 6 A) and being seated within a pair of terminal strips ( 6 B), respectively; and 
     FIGS. 7A and 7B are side elevational views of the bridge clip being inserted into the connector ( 7 A) and being seated within the pair of terminal strips ( 7 B), respectively. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Generally speaking, in accordance the present invention, a connector testing system is provided that provides a more reliable testing configuration. 
     Referring first to FIGS. 6A and 7A, a connector testing system  50  includes a connector  10 , having a pair of terminal strips  40  and a housing  25 , and a bridge clip  30 . Connector  10  includes a top section, generally indicated as  12 , and a bottom section, generally indicated as  14 . Top section  12  is pivotably mounted to bottom section  14  about a fixed axis  82 , and includes a cap  17  having a stem  18  and a catch  19 . Preferably, cap  17  is generally t-shaped when seen from the side elevational view. Top section  12  has a clasp  15 , which is movable between an engaged position and a disengaged position, for engaging top section  12  to bottom section  14 . Connector  10  has two entrance apertures  22  that lead to wire insertion holes  20 . Wire insertion holes  20  are constructed so as to accept electrical conductors (not shown) in a manner known in the art. Connector  10  also includes housing  25 , which is constructed to accept a pair of terminal strips  40  when the top section  12  is in the closed position as is shown in FIGS. 6A and 7A. Housing  25  includes side walls  26 , a front wall  27  and a rear wall  28 , extending between side walls  26  (FIG.  7 A), and a base  29 , positioned substantially perpendicular to side walls  26 , front wall  27  and rear wall  28  and extending therebetween. Base  29  has throughholes  29  a sized to accept snap fit recesses  41  of terminal strip  40 , which are secured through the mating engagement of throughholes  29   a  and snap fit recesses  41  of terminal strip  40 . 
     Connector  10  is preferably formed of a molded synthetic resinous material with good insulating properties and mechanical strength. The specific materials utilized in constructing connector  10  are an application specific matter of design choice within the knowledge of the person of skill familiar with terminal blocks utilized in the telephony art. Moreover, the specific means of affixing terminal strip  40  within housing  25  need not be solely by snap fitting as described above, but by numerous methods of affixation known in the art, such as by way of non-limiting example, adhesives, friction fitting, integral molding, screws, and the like, depending on whether ready removal and re-insertion of the terminal is required, as a matter of application-specific design choice. 
     With reference to FIGS. 1 through 3, an elongated terminal strip  40  of the present invention is shown in greater detail. Terminal strip  40  has a longitudinal axis extending in a direction shown as arrow Y in FIG. 1, and includes a first arm  42 , having a first tip  44 , and a second arm  43 , having a second tip  45 . First tip  44  and second tip  45  form a wire gripping region  46  for retaining an electrical conductor (not shown) that has been inserted into wire insertion holes  20  of top section  12  of connector  10 . Terminal strip  40  includes a base  47  formed by first arm  42  and second arm  43  at the end opposite tips  44 ,  45 . 
     Terminal strip  40  also includes a side fold or pocket for forming a retention channel, generally indicated as  60 , having a connector plate  63 . Preferably, side fold  60  is generally u-shaped in the elevational view as shown in FIG. 1, but may be shaped in any manner, provided that it is constructed so as to retain the leading edge of a test probe lead when the lead is inserted within side fold  60 , as discussed further below. In this manner, side fold  60  forms a test point for testing the integrity of a circuit of which terminal strip  40  is a part. Side fold  60  is preferably, though not necessarily, integrally formed with terminal strip  40 , but may be attached by any means know to those skilled in the art, such as by way of non-limiting example, friction fitting, integral molding, screws, and the like. Further, those skilled in the art will recognize that side fold  60  may be attached to either side of terminal strip  40 ; i.e., to first tip  44  or to second tip  45 , or to any structure adjacent terminal strip  40 . Side fold  60  further includes a retention plate  64  positioned substantially parallel to connector plate  63 . Retention plate  64  has a free end  61  and a fixed end  65  and is resiliently connected to connector plate  63  by an elbow  66 . Connector plate  63 , elbow  66  and retention plate  64  may all be integrally formed with terminal strip  40 , or simply positioned in close proximity thereto. Side fold  60  has an opening  69  formed near free end  61  sized to receive the end of a test lead. Retention plate  64  optionally has a receptacle  67  for engaging the test lead of a bridge clip (described below). Receptacle  67  may take the form of a throughhole, a bore or an indentation. Free end  61  preferably also includes a flared portion  62  for guiding the bridge clip test lead to its seated position. 
     In an alternative embodiment, shown in FIG. 6A, side fold  60  is pinched at free end  61  so that, in the absence of a test lead, free end  61  of retention plate  64  is biased against connector plate  63 . In this embodiment, when a test lead of a bridge clip is inserted within side fold  60 , side fold  60  acts as a spring or clip and retention plate  64  is biased and retained against the test lead to reliably secure the test lead and provide a stable electrical contact. 
     In all embodiments, terminal strip  40 , including side fold  60 , may be formed of any commonly known electrically conductive metal or electrical conductor known in the art and suitable for use in such terminals, such as, for example, platinum-washed phosphor bronze, or beryllium-cooper alloy or any other material, metal or alloy combining good electrical conductivity with sufficient mechanical strength and resilience. 
     Referring to FIGS. 4 and 5, bridge clip  30  is depicted in greater detail. Bridge clip  30  includes a body  31 , and test leads  32 ,  33  and electrical conductors  34 ,  35 . Test lead  32  and conductor  34  are connected to body  31  at connection region  36 , and test lead  33  and conductor  35  are connected to body  31  at connection region  37 . Test lead  32  has an end  32   a  and forms an electrical connection through connection region  36  and electrical conductor  34  to a testing device (not shown). Likewise, test lead  33  has an end  33   a  and forms an electrical connection through connection region  37  and electrical conductor  35  to the testing device. Test leads  32 ,  33  are preferably straight, flat electrically conductive blades having dimples or projections  38 ,  39 , respectively, formed on a lower portion of leads  32 ,  33 . Dimples  38 ,  39  are preferably substantially hemispherical and are positioned such that when test leads  32 ,  33  are positioned within side folds  60  of a pair of terminal strips  40 , dimples  38 ,  39  are accommodated within receptacles  67  of retention plate  64 . Dimples  38 ,  39  can be any shape and receptacles  67  may be sized and constructed to receive dimples  38 ,  39  so as to provide a reliable electrical connection. 
     In this manner, a positive latch between bridge clip  30  and connector  10  is provided to eliminate the need for the user to hold bridge clip  30  to connector  10  during testing. Dimples  38 ,  39  provide improved contact surface area with receptacles  67  of side folds  60  due to the greater surface area of the substantially hemispherical dimples  38 ,  39  as compared with a flat surface. Further, rather than having the limited contact points generally associated when planar surfaces are brought into contact, dimples  38 ,  39  contact receptacles  67  all along the outer periphery of the dimple. 
     By capturing test leads  32 ,  33  within side folds  60 , connector  10  is protected form damage that may be caused by overinsertion of test leads  32 ,  33  into connector  10 . In addition, when dimples  38 ,  39  are received within receptacles  67  of sidefolds  60 , the user feels or discerns a perceptible signal or “click” that indicates, through positive feedback that test leads  32 ,  33  are properly positioned within side folds  60  and a proper electrical connection has been achieved. 
     Bridge clip  30  also includes a latch  48  having a first beam  78  formed with a first hook  58 , and a second beam  79  formed with a second hook  59 . Preferably, beams  78 ,  79  and hooks  58 ,  59  are integrally formed with body  31 , however, hooks  58 ,  59  may be connected to beams  78 ,  79  in any fashion known to those skilled in the art. First hook  58  and second hook  59  are constructed to matingly engage with catch  19  of cap  17  when test leads  32 ,  33  of bridge clip  30  are inserted into retention plates  64 . 
     Latch  48  is preferably spring-loaded. That is, beams  78  and  79  are elastically deformable and thus act as a release mechanism when a force shown as arrows F is applied to beams  78 ,  79  thereby deflecting beams  78 ,  79  inwardly and rotating hooks  58 ,  59  outwardly from catch  19  in a direction shown by arrow A to disengage from catch  19  as shown in FIG.  7 A. Thus, latch  48  is in its open position as shown in FIG. 7A, when beams  78 ,  79  are deflected inwardly by a force F. Conversely, as shown in FIG. 7B, latch  48  is in its closed position when test leads  32 ,  33  are inserted into side fold  60  and first hook  58  and second hook  59  engage catch  19  of cap  18 . 
     Thus, positive securement between bridge clip  30  and terminal strips  40  can be ensured by latch  48 , by side folds  60  in combination with test leads  32 ,  33 , or by the retention of dimples  38 ,  39  within receptacles  67 . Depending on the application, any one or all three of these devices can be used to ensure reliable contact between bridge clip  30  and connector  10  and eliminate the need to hold bridge clip  30  after inserting bridge clip  30  to contact terminal strips  40 . 
     One example of a connector that utilizes the securement devices described above is depicted in FIGS. 6A,  6 B,  7 A and  7 B. FIGS. 6A and 7A are front and side elevational views, respectively, of test leads  32 ,  33  of bridge clip  30  just prior to being inserted into side folds  60  of a pair of terminal strips  40  disposed within housing  25  of connector  10 . FIGS. 6B and 7B depict test leads  32 ,  33  of bridge clip  30  seated within side folds  60  of terminal strips  40 . 
     Referring to FIG. 6A, housing  25  is formed to accept a pair of terminal strips  40 . To facilitate testing of connections made through the connector, test or insertion channels  70  are formed between housing  25 , and top section  12  and bottom section  14  of connector  10  to permit test leads  32  and  33  to be inserted so as to contact terminal strips  40 . To secure bridge clip  30  to connector  10 , as the user inserts the test leads  32 ,  33  into test channels  70 , the user compresses beams  78  and  79  in the direction shown as arrows F to rotate hooks  58  and  59  outward in the direction shown by arrows A. Once hooks  58  and  59  rotate a distance sufficient to clear catch  19 , the user continues to insert test leads  32 ,  33  until test lead ends  32  a,  33  a contact flared portions  62  of side folds  60 . Further insertion of test leads  32 ,  33  cause retention plates  64  to rotate in a direction indicated by arrows B until test leads  32 ,  33  are permitted to slide into side folds  60 . As is shown in FIGS. 6B and 7B, upon further insertion of test leads  32 ,  33 , dimples  38  and  39  become seated within receptacles  67 . At this time, the user can stop compressing beams  78  and  79 , which permits hooks  58  and  59  to rotate to the closed position and engage catch  19  of top section  12  of connector  10 . In the fully inserted position, test leads  32 ,  33  are cupped within side folds  60 , and dimples  38 ,  39  are seated within receptacles  67 . 
     In this manner, the testing configuration provides a more reliable electrical connection and eliminates the need to hold the bridge clip when testing the electrical conductors housed within the connector. 
     Thus, while there have been shown and described and pointed out fundamental novel features of the invention as applied to preferred embodiments thereof, it will be understood that various omissions and substitutions and changes in the form and details of the disclosed invention may be made by those skilled in the art without departing from the spirit of the invention. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.