Patent Publication Number: US-6217352-B1

Title: Electrical connectors having dual biased contact pins

Description:
This application is a continuation-in-part of U.S. patent application Ser. No. 09/271,620, filed Mar. 17, 1999, now U.S. Pat. No. 6,102,714, which is a continuation-in-part of U.S. patent application Ser. No. 09/033,270, filed Mar. 2, 1998, now U.S. Pat. No. 6,116,927. These applications are hereby incorporated by reference in their entireties. 
    
    
     BACKGROUND OF THE INVENTION 
     1. The Field of the Invention 
     The present invention relates to electrical connectors for use with media plugs and, more specifically, sliding pin assemblies configured to establish electrical communication between a media plug and a PCB. 
     2. Present State of the Art 
     Electrical apparatus, such as personal computers, cellular telephones, and personal information managers (PIMs), are becoming increasingly dependent upon their ability to electrically communicate or share information with other electrical apparatus. To facilitate this electrical communication, a variety of different types of electrical couplers have been developed. An electrical coupler includes a plug and a corresponding jack or connector. The jack typically includes an aperture or socket configured to receive the plug so as to establish electrical communication therebetween. 
     Select types of electrical couplers have been designed for use with PC cards. A PC card is a small thin card typically having a standard size. A first type of connector is formed at one end of the PC card and is configured to couple with the electrical apparatus. A second type of connector or jack is formed at the opposing end of the PC card and is configured to couple with a desired outside line such as a telephone line or a network line. Disposed within the PC card is a circuit board providing the necessary circuitry to perform one or more intended functions. For example, in one type of PC card, the circuit board comprises a modem which enables the electrical apparatus to receive and transmit information over telephone lines. In another PC card, the circuit board enables the electrical apparatus to receive and transmit information with a network system over a network cable. 
     One conventional type of jack used for connecting a PC card to an exterior line comprises a thin plate which is slidably mounted to the PC card. The plate has a top surface with an aperture formed therein. A plurality of short contact pins are rigidly mounted to the thin plate. Each contact pin has a first end that is freely exposed within the aperture and an opposed second end mounted to the plate. A flexible wire ribbon has a first end that is soldered to the second end of the contact pins and an opposing second end that is soldered to contacts on the circuit board within the PC card. 
     The thin plate can selectively slide between an extended position and a retracted position. In the extended position, the aperture is exposed such that a corresponding plug, for example an RJ-11, commonly referred to as a telephone plug, can be received therein. The plug pushes against the contact pins so as to establish electrical contact therewith. As a result, electrical communication is established from the plug, through the contact pins and flexible wire ribbon, to the circuit board. When not in use, the thin plate is retracted by sliding back within the PC card such that the aperture is not exposed. The ability to repeatedly slide the plate between the extended and retracted position while maintaining electrical communication between the pins and the circuit board is attributed to the flexible wire ribbon. That is, the wire ribbon freely bends or folds as the plate is retracted and then unfolds as the plate is extended. 
     Although effective in establishing electrical communication between a plug and a circuit board of a PC card, the above described sliding jack has several drawbacks. For example, repeated movement of the plate between the retracted and extended position produces stresses on the flexible wire ribbon and its soldered contacts. These stresses eventually result in fatigue failure of the wire ribbon and/or the solder contact. Moreover, during the manufacturing process, soldering requires high temperatures which potentially serve to deform the materials used in the flexible wire ribbon. Often these materials are plastic and can be catastrophically destroyed. Additionally, during the solder manufacturing process, too much solder applied at areas of electrical connections can cause the solder to spread and potentially cause electrical shorts. 
     Furthermore, since the slidable plate is fixedly attached to the circuit board by the flexible wire ribbon, it is difficult if not impossible to replace or repair the plate or pins. Thus if any element of the electrical coupling system is damaged, either the PC card must be returned to the manufacturer for repair, or a new PC card must be purchased. 
     Still other limitations exist within the manufacturing process. The flexible wire ribbon is positioned on the circuit board by techniques commonly known as “pick-and-place.” Although generally effective, the pick-and-place process often “loses” the flexible wire ribbon as it is being positioned on the PCB. This losing then disrupts the manufacturing line, especially automated ones. It can also cause the flexible wire ribbon to be incorrectly positioned on the PCB. Moreover, pick-and-place may overstress the wires or conductors within the ribbon when maneuvering. This can potentially causes failure of the conductors. 
     Another inherent limitation is the spatial arrangement that must exist within the communications card to allow the sliding plate to freely move without constriction from the flexible wire ribbon. That is, a relatively large free area must be formed within the card to enable the wire ribbon to freely move and flex. This free area limits the size of the circuit board and the number of electrical components that can be positioned thereon. 
     Another problem associated with conventional retractable jacks relates to the pin configuration. The contact pins in a conventional retractable jack have a first end freely exposed within the aperture and a second end that is rigidly secured to the thin plate. Insertion of the plug into the aperture bends the pins downwardly, and removal of the plug causes the pins to resiliently flex back to their original configuration. Repeated insertion and removal of the plug can produce localized stresses within the pins that eventually result in fatigue failure. 
     The contact pins in a correctional retractable jack can also be bent or deformed such that a plug inverted into the aperture cannot establish electrical contact with the jack. For example, one or more of the contact pins can be bent beyond their elastic limit and this prevents the pins from resiliently returning to their original position. This may also prevent the pins from properly biasing against corresponding contacts on the plug. Additionally, the contact pins may be bent such that one or more of the contact pins touch or are in electrical communication with each other. Further, one or more of the contact pins may be knocked out of alignment such that the pins do not electrically communicate with the corresponding contacts on the plug. 
     OBJECTS AND BRIEF SUMMARY OF THE INVENTION 
     Accordingly, it is an object of the present invention to provide improved connectors for facilitating electrical communication between a media plug and an electrical apparatus. 
     Another object of the present invention is to provide connectors as above that substantially eliminate reliance upon solder joints and flexible wire ribbons. 
     It is another object of the present invention to provide improved connectors that are easily manufactured and can be positioned by pick-and-place manufacturing. 
     Still another object of the present invention is to provide connectors as above wherein the system includes a retractable slide plate that can be repeatedly removed and replaced without damage to the system. 
     It is a further object of the present invention to provide connectors that consume less physical space. 
     It is still a further object of the present invention to provide improved connectors that substantially eliminate the possibility of electrically shorting components. 
     Another object of the present invention is to provide improved connectors having contact pins wherein the potential for localized fatigue and bending beyond an elastic point is minimized. 
     Yet another object of the present invention is to provide improved connectors with contact pins that remain correctly aligned and in the proper location. 
     To achieve the foregoing and other objectives, and in accordance with the invention as embodied and broadly described herein, a jack is provided for facilitating electrical communication between a media plug, such as an RJ-type plug, and a printed circuit board (PCB) or other similar type of rigid member disposed in an electrical apparatus. Examples of electrical apparatus include lap top computer, personal information manager, or cellular telephone. The PCB has an elongated finger that extends to a free distal end. A plurality of contact lines are formed on the top surface of the finger. The portion of the contact lines at the distal end of the PCB finger are openly exposed while the remainder of the contact lines are covered by an insulating layer. 
     The jack is slidably mounted on the PCB finger. More specifically, the jack includes a slide plate having an aperture extending therethrough and a channel communicating with the aperture. Mounted on the slide plate so as to be positioned over the channel is a pin block. The pin block has a plurality of elongated slots formed therein. The slots face the channel and are separated by insulating walls. Disposed within each of the elongated slots is a substantially S-shaped pin. Each pin has a tail end that is mounted to the pin block, a downwardly curved portion that extends within the channel, and an opposing lead end which is freely disposed within the aperture of the slide plate. 
     In another preferred embodiment, the tail ends of the contact pins are attached to the pin block and a center portion of the contact pins are also attached to the pin block. In particular, a yoke block is preferably used to attach the tail ends of the contact pins to the pin block and a central guide is preferably used to attach the center portion of the contact pins to the pin block. Advantageously, the central guide keeps the pins correctly aligned and in the correct locations. Significantly, because the pins are correctly aligned, the pin block does not require slots or walls proximate the front end of the pin block. 
     During assembly, the finger of the PCB is slidably received within the channel of the slide plate such that the jack can be selectively moved between an extended position on the electrical apparatus and a retracted position within the electrical apparatus. In the retracted position, the slide plate is slid along PCB finger such that the aperture is substantially enclosed within the electrical apparatus. In this position, the downwardly curved portion of each pin is positioned over an insulated portion of the contact lines on the PCB. As a result, each contact pin is insulated from electrical communication with a corresponding contact line. 
     In the extended position, the slide plate is advanced outward along the PCB finger so as to openly expose the aperture. In this position, the downwardly curved portion of each pin is biased against the exposed portion of a corresponding contact line on the PCB. As a result, each pin is in electrical communication with the corresponding contact line. In this extended position, the media plug is selectively received within the aperture so as to bias in electrical communication against the lead end of each pin. As a result, electrical communication is facilitated between the media plug and corresponding contact lines on the PCB through the pins. In turn, the contact lines can be placed in electrical communication with the electrical apparatus in any conventional manner. 
     The contact pins are desirably sized and configured such that the pins have a relatively small contact force with the insulated portion of the contact lines on the PCB when the jack is located in the retracted position. The pins are also desirably sized and configured the jack is in the extended position and the plug is inserted into the jack. Advantageously, this allows for positive electrical communication between the contact pins and corresponding contact lines when the jack is extended, and this decreases sliding friction between the contact pins and the insulated contact lines when the jack is retracted. 
     The inventive jack and related pins have a variety of advantages over prior art systems. For example, as a result of the pins facilitating electrical communication with the PCB by biased rather then fixed engagement, the required use of the flexible wire ribbon is eliminated. The elimination of the flexible wire ribbon not only greatly simplifies the manufacturing process but also eliminates problems associated with soldering and eliminates failures due to fatigue and ware of the flexible wire and soldered contacts. In addition, by removing the flexible wire ribbon, the jack as set forth herein can be repeatedly separated from the system and selectively reattached by an end user without damage to the system. 
     Furthermore, the unique configuration and use of the pins enables the pins to have a relatively long length. This long length enables the pins to more evenly distribute stresses along the length of the pin. As a result, the inventive pins experience less localized fatigue and have a reduced potential for bending beyond their point of elastic deformation. 
     These and other objects, features, and advantages of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In order that the manner in which the above-recited and other advantages and objects of the invention are obtained, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which: 
     FIG. 1 is a perspective view of a laptop computer having one embodiment of an inventive modular connector attached thereto; 
     FIG. 2 is a perspective view of the modular connector shown in FIG. 1; 
     FIG. 3 is an exploded view of the modular connector shown in FIG. 2; 
     FIG. 4 is a perspective view of the frame of the modular connector shown in FIG. 3; 
     FIG. 5 is an exploded view of the jack of the modular connector shown in FIG. 3; 
     FIG. 6 is a side view of the pin assembly of the jack shown in FIG. 5; 
     FIG. 7 is a perspective view of the modular connector shown in FIG. 2 with the cover removed therefrom; 
     FIG. 8 is a cross sectional side view of the modular connector shown in FIG. 7 taken along section lines  8 — 8 ; 
     FIG. 9 is a cross sectional side view of the jack shown in FIG. 7 in a retracted position; 
     FIG. 9A is a front view of the U-shape saddle depicted in FIG. 9; 
     FIG. 10 is a cross sectional side view of the jack shown in FIG. 7 in an extended position; 
     FIG. 11 is a cross sectional side view of an alternative embodiment of the jack shown in FIG. 10; 
     FIG. 12 is an exploded perspective view of a portion of a modular connector in accordance with another preferred embodiment of the present invention, illustrating a contact pin assembly; 
     FIG. 13 is a cross sectional side view of a portion of the modular connector shown in FIG. 12, illustrating the jack in a retracted position; 
     FIG. 14 is a perspective view of the contact pin assembly shown in FIG. 12; and 
     FIG. 15 is a side view of the contact pin assembly shown in FIG.  14 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Depicted in FIG. 1 is a lap top computer  10  having mounted thereon one embodiment of a physical/electrical modular connector  12  incorporating novel features of the present invention. Modular connector  12  is configured to both physically and electrically couple a media plug  13  to a desired electrical apparatus such as computer  10 . As used in the specification and appended claims, the term “media plug” is broadly intended to include RJ-type plugs such as the RJ-11, R-45, and other RJ-types plugs which currently exist or will be developed in the future under new standards. The term “media plug” also includes those plugs having physical attributes that fall under F.C.C. Part 68, Subpart F. Although modular connector  12  is shown mounted on lap top computer  10 , modular connect  12  can similarly be mounted on virtually any type of electrical apparatus that requires electrical coupling with a cable such as a telephone line or network line. Examples of such electrical apparatus include cellular phones, pagers, personal information managers (PIM), PCMCIA cards, network cards, notebook computers, personal computers, diagnostic equipment, and other hand operated electrical devices. 
     Depicted in FIG. 2, modular connector  12  comprises a housing  14  having a jack  16  retractably mounted within a compartment  18  thereof One of the unique features of modular connector  12  is that it can be easily removed or attached to a variety of different electrical apparatus. Prior art jacks were integrally constructed with a corresponding electrical apparatus, thereby making it difficult if not impossible to add or remove a jack. In contrast, as discussed later in greater detail, as a result of connector  12  being modular, housing  14  can be easily mounted or removed from a printed circuit board (PCB) or other structural feature of an electrical apparatus. 
     Depicted in FIG. 3, housing  14  comprises a frame  22 , a retainer  26 , and a cover  28 . Mounted to housing  14  is a board assembly  24 . As depicted in FIG. 3 and 4, frame  22  has a substantially U-shaped configuration which includes a first arm  30  and a spaced apart second arm  32  each in substantially parallel alignment. Each arm  30  and  32  extends between a free first end  34  and an opposing second end  36 . Extending between second ends  36  of arms  30  and  32  is a cross member  38 . A plurality of retention holes  45  extend through second arm  32  and cross member  38 . 
     In one embodiment of the present invention, means are provided for securing housing  14  to a structure. By way of example and not by limitation, projecting from each arm  30  and  32  adjacent to first end  34  is a post  40 . Radially outwardly projecting from post  40  is a barb  42 . Transversely extending through the end of post  40  is slot  44 . Accordingly, by pushing post  40  through an aperture, such as on a PCB, barb  42  is free to compress and then expand on the opposing side of the PCB, thereby securing frame  22  thereto. As an alternative to the means, projecting from cross member  38  are a pair of spaced apart tabs  46 . Each tab  46  has an aperture  48  extending therethrough. Each aperture  48  is configured to receive a post, such as may be projecting from a PCB or other structure. The present invention also envisions that there are a variety of different tongue and groove or other types of catches known to those skilled in the art that can be used for securing frame  22  to a structure. 
     First arm  30  has an inside face  50  with a substantially T-shaped member  52  inwardly projecting therefrom. Member  52  comprises a narrow elongated stem  51  projecting from inside face  50  along the length thereof and an enlarged rail  53  formed at the end of stem  51  and also extending substantially the length of first arm  30 . Rail  53  has an exposed inside face  57 . Formed between rail  53  and first arm  30  on opposing sides of stem  51  are a pair of narrow tracks  55 . Mounted on cross member  38  adjacent to first arm  30  is a block  49 . Projecting from block  49  in substantially parallel alignment with first and second arms  30  and  32  is a post  54  having a spring  56  mounted thereon. Rail  53  and spring  56  interact with jack  16  and will be discussed later therewith. 
     Depicted in FIG. 3, board assembly  24  comprises a PCB  62  including a base portion  64  and an elongated center finger  66  projecting from base portion  64  to a free distal end  58 . Also projecting from base portion  64  and substantially in parallel alignment with center finger  66  is an elongated side finger  68 . An elongated slot  70  extends between fingers  66  and  68 . Disposed on base portion  64  is an electrical connector  72 . In one embodiment, connector  72  comprises a zero-insertion-force (ZIF) connector available from  3 Com. In alternative embodiments, connector  72  can comprise any of a plurality of different types of connectors for connecting either a flexible wire or a rigid plug to board assembly  24 . In yet other embodiments, fixed pins can project from PCB  62  for electrical coupling with an electrical apparatus upon attachment of housing  14  thereto. 
     Formed on the top surface of PCB  62  are a pair of contact lines  74  and  76 . Contact lines  74  and  76  extend from connector  72  to distal end  58  of center finger  66 . Contact lines  74  and  76  include an exposed portion  78  wherein contact lines  74  and  76  are in substantially parallel alignment and are freely exposed on the top surface of center fingers  66 . Contact lines  74  and  76  also include a covered portion  80  which is covered or otherwise insulated on PCB  62  and extends from exposed portion  78  to connector  72 . In alternative embodiment, any number of contact lines can be formed on PCB  62 . The number of contact lines generally depends on the intended use of modular connector  12  and the type of media plug with which it will interact. In alternative embodiments, board assembly  24  can be comprised of any board like member on which contact lines  74  and  76  can be formed independent of the method. 
     In one embodiment, a light source  82 , such as a light emitting diode, an incandescent light, or the like, is mounted at the distal end of side finger  68 . Contact lines can extend from connector  72  to light sources  82  on PCB  62  for energizing. Formed on base portion  64  and side finger  68  are a plurality of retention holes  84 . During assembly, board assembly  24  is disposed on frame  22  such that base portion  64  rests on cross member  38 , side finger  68  rests on second arm  32 , and center finger  66  is freely disposed between first arm  30  and second arm  32 . In this position, retention holes  84  on board assembly  24  are aligned with retention holes  45  on frame  22 . 
     Retainer  26  has a substantially L-shaped configuration having a plurality of locking posts  86  projecting from the bottom surface thereof Retainer  26  is configured to be disposed on top of base portion  64  and side finger  68  of PCB  62  such that locking posts  86  pass through corresponding retention holes  84  and retention holes  45 , thereby securing board assembly  24  to frame  22 . 
     Cover  28  comprises a top wall  90  having a pair of opposing side walls  92  and  94  downwardly projecting from the sides thereof Inwardly projecting from the free end of each side arm  92  and  94  is a retention lip  96 . As depicted in FIG. 2, cover  28  is configured to be positioned over the assembled frame  22 , board assembly  24 , and retainer  26 . Retention lips  96  bias against the bottom surface of frame  22  so as to retain cover  28  in position. In one embodiment, cover  28  is comprised of a thin sheet of stainless steel. In alternative embodiments, cover  28  can be comprised of other metallic or insulating materials. 
     Depicted in FIG. 5, jack  16  comprises a slide plate  100  having a pin assembly  102  secured thereto by a pin block  104 . Slide plate  100  comprises a pair of spaced apart substantially parallel side walls  106  and  108 . Each side wall  106  and  108  extends between a front end  110  and an opposing back end  112 . Extending between opposing front ends  110  is a front wall  114 . As depicted in FIGS. 5 and 9, extending through slide plate  100  between side walls  106  and  108  adjacent to front wall  14  is an aperture  116 . Aperture  116  is configured to receive media plug  13 . In the embodiment depicted, aperture  116  extends through slide plate  100  at an angle orthogonal to the plane of slide plate  100 . In alternative embodiment, aperture  116  can be sloped at an angle less than 90° relative to the plane of slide plate  100 . 
     In one embodiment of the present invention, means are provided for releasably securing media plug  13  within aperture  116 . By way of example and not by limitation, projecting into aperture  116  from front wall  14  is a catch lip  128 . Catch lip  128  is configured to engage the prong on a conventional RJ-11 plug so as to mechanically retain the plug within aperture  116 . Alternative embodiments for the orientation of aperture  116  and for the releasably securing means are disclosed in U.S. Pat. No. 5,547,401, filed Aug. 16, 1994 (hereinafter “the &#39;401 patent”), and U.S. patent application Ser. No. 09/357,017, filed Jul. 19, 1999 (hereinafter “the &#39;017 application”), which are incorporated herein by specific reference. 
     The present invention also includes means for preventing the passage of media plug  13  completely through aperture  116 . By way of example and not by limitation, as depicted in FIGS. 9 and 9 a , rotatably extending between side walls  106  and  108  in alignment with aperture  116  is a substantially U-shaped saddle  130 . Saddle  130  acts as a stop to prevent media plug  13  from passing too far through aperture  116 . Examples of other embodiments of the means for preventing the passage of media plug  13  include an elastic member, ledge, or spring disposed below aperture  116 . Examples of these and other embodiments of the means for preventing the passage of media plug  13  are disclosed in the &#39;401 patent and &#39;017 application which were previously incorporated herein by specific reference. 
     As also depicted in FIG. 9, a floor  118  extends between side walls  106  and  108  adjacent to aperture  116 . Floor  118  has a tapered back end  119  and an opposing front end  121  bounding aperture  116 . As better seen in FIG. 5, floor  118  and side walls  106  and  108  bound a channel  132  which is aligned with and communicates with aperture  116 . In one embodiment, slide plate  100  can be comprised of an opaque material. In yet another embodiment, slide plate  100  can be manufactured from a translucent material such that light source  82  can illuminate slide plate  100 . An example of the configuration of slide plate  100  for illumination by light source  82  is disclosed in U.S. Pat. No. 6,159,037 which is incorporated herein by specific reference. 
     Pin assembly  102  comprises a plurality of substantially S-shaped pins  150  that are coupled in substantially parallel alignment by a yoke block  148 . The term “S-shaped” is broadly intended to includes the shape of any pins wherein opposing ends are curved in opposing directions. As depicted in FIG. 6, each pin  150  extends from a lead end  152  to an opposing tail end  154 . The distance between lead end  152  and yoke block  148  along pin  150  is typically in a range between about 14 mm to about 25 mm, with about 17 mm to about 22 mm being more preferred. Formed adjacent to lead end  152  is an upwardly curved portion  156 . In alternative embodiments, curved portion  156  can be straight. Disposed adjacent to tail end  154  is a downwardly curved portion  158 . Tail end  154  of each pin  150  is secured together by yoke block  148 . In the embodiment depicted, yoke block  148  extends between opposing ends  149  and has a substantially square transverse cross section. 
     Pin block  104  has a shallow box-like configuration having a flat top surface  160  and an opposing bottom surface  162  each extending between a front end  164  and an opposing back end  166 . Pin block  104  also has opposing side walls  146  and  147 . Formed on bottom surface  162  at front end  164  are a plurality of elongated slots  168  separated by insulating walls  170 . As better seen in FIG. 9, a back wall  140  and a boundary wall  142  transversely extend between opposing side wall  146  and  147  at back end  166 . Back wall  140  and boundary wall  142  bound a compartment  138  therebetween. Returning back to FIG. 5, an aperture  144  extends through each side wall  146  and  147  so as to communicate with compartment  138 . 
     During assembly, opposing ends  149  of yoke block  148  are snap fit within apertures  144  so as to secure pin assembly  102  to pin block  104 . In the embodiment depicted, apertures  144  have a substantially square cross section that is complementary to the transverse cross section of yoke block  148 . As such, yoke block  148  is prevented from rotating once it is received within apertures  144 . In this position, each pin  150  is received within a corresponding slot  168  with lead end  152  freely projecting past front end  164  of pin block  104 . Insulating walls  170  prevent contact between pins  150 . Pin block  104  is then secured between opposing side walls  106  and  108  of slide plate  100  as depicted in FIG.  7 . In this configuration, pins  150  are disposed within channel  132  while lead end  152  of each pin  150  is vertically disposed within aperture  116 . 
     In one embodiment of the present invention, means are provided for preventing annular rotation of tail end  154  of pin  150  relative to pin block  104 . By way of example and not by limitation, as a result of yoke block  148  having a transverse square cross section that is complementary to apertures  144  in pin block  104 , tail end  154  of each pin  150  is prevented from annular rotation relative to pin block  104  when opposing ends of yoke block  148  are received within apertures  144 . Other polygonal shapes such as a triangle, rectangle, pentagon, or the like, would also served to perform the same function. 
     In yet another alternative embodiment, as depicted in FIG. 11, a yoke block  200  is provided having a substantially cylindrical shape. Apertures  144  on pin block  104  can have a circular, square, or any other configuration that will receive the opposing ends of yoke block  200 . In this embodiment, however, pin  150  is configured such that when yoke block  200  is received within apertures  144 , tail end  154  of pin  150  is biased against pin block  104  so as to prevent annular rotation of pin  150  around yoke block  200 . 
     In other embodiments, pins  150  can be configured to rotate relative to pin block  104 . For example, tail end  154  of pin  150 , as shown in FIG. 11, can also be configured to terminate within cylindrical yoke block  200 . By forming apertures  144  such that the opposing ends of yoke block  200  can freely rotate therein, pins  150  are free to rotate about an axis extending through cylindrical yoke block  200 . 
     Once jack  16  is assembled, it can be removably attached to housing  14  as shown in FIG.  7 . Returning back to FIG. 5, rearwardly projecting from side wall  106  of slide plate  100  is an elongated slide arm  120 . Slide arm  120  has a substantially C-shaped transverse cross section that terminates at a pair of inwardly facing rails  124  and  126 . Each rail  124  and  126  extends between an inwardly tapered end  178  and an opposing flat end  180 . Slide arm  120  is configured such that rails  124  and  126  can be selectively received within opposing tracks  55  on frame  22 . Slide plate  100  can thus selectively extend and retract by sliding along the length of tracks  55 . 
     In one embodiment of the present invention, means are provided for releasably securing jack  16  to housing  14 . By way of example and not by limitation, depicted in FIG. 8, elongated stem  51  of frame  22  includes an enlarged head  182  that tapers at an abrupt shoulder  184  to an elongated narrow body  186 . The front end of head  182  has tapered shoulder  188  formed thereon. During assembly, tapered end  178  of rails  124  and  126  are pushed against tapered shoulder  188  of stem  51 . As a result of the complementary tapers and the applied force, rails  124  and  126  resiliently expand enabling rails  124  and  126  to pass over head  182  and then snap back over narrow body  186 . Rails  124  and  126  can then freely slid back and forth along narrow body  186  without disengaging from frame  22 . 
     Contact between flat end  180  of rails  124  and  126  and shoulder  184  of stem  51  prevents jack  16  from accidentally sliding off of stem  51 . The present system is designed, however, such that when sufficient pulling force is applied to jack  16  relative to housing  14 , rails  124  and  126  spread sufficiently far apart to allow rails  124  and  126  to pass over head  182 , thereby permitting removal of jack  16  from housing  14  without damaging either component. When desired, jack  16  can simple be replaced as discussed above. The amount of force required to remove jack  16  can be varied by varying the design. That is, the desired force is decreased by narrowing the width of head  182  or increasing the gap between rails  124  and  126 . Furthermore, the force can be decreased by tapering shoulder  184  and/or end  180  of rails  124  and  126 . 
     With jack  16  attached to housing  14  as discussed above, jack  16  can be selectively moved between a retracted position wherein jack  16  is slid back into housing  14  so as to be substantially enclosed therein and an extended position wherein the front end of jack  16  projects out of housing  14  such that aperture  116  is openly exposed. In one embodiment, means are provided for biasing jack  16  into the extended position. By way of example and not by limitation, depicted in FIGS. 4 and 5, spring  56  mounted on post  54  of frame  22  is received within channel  122  of elongated side arm  120  so as to bias against wall  106  of slide plate  100 . As a result, spring  56  continually biases jack  16  into the extended position. 
     In alternative embodiments, it is envisioned that spring  56  can be placed at different locations to bias against jack  16 . Furthermore, spring  56  can be replaced with other conventional types of springs such as a leaf spring. Examples of alternative embodiments of the means for biasing jack  16  outward are disclosed in the &#39;401 patent and &#39;017 application which were previously incorporated herein by specific reference. 
     The present invention also includes means for selectively retaining jack  16  in the retracted position. By way of example and not by limitation, depicted in FIGS. 4 and 5, inside face  57  on rail  53  of frame  22  has a channel  186  recessed therein. A substantially heart-shaped groove  188  having a substantially heart-shaped guide  190  disposed in the center thereof is formed at the end of channel  186 . A pin  192  is rotatably disposed within a recess  195  formed on the outside face of side arm  106  of slide plate  100 . The free end of pin  192  is configured to be received within channel  186  when jack  16  is slidably attached to housing  14  as discussed above. As jack  16  is manually retracted or pushed within housing  14 , pin  192  travels along channel  186  into groove  188 . As a result of channel  186  being slightly offset above guide  190 , pin  192  first travels in an upper side channel  191  which curves around to a first alcove  194 . Alcove  194  stops the progression of pin  192  and thus jack  16 . As jack  16  is manually released, spring  56  produces a biasing outward force on jack  16  causing pin  192  to move into a saddle  196  formed on guide  190 . The contact between pin  192  and saddle  196  prevents jack  16 , which is continually urged by spring  56 , from automatically advancing out into the extended position. 
     To move jack  16  back into the extended position, jack  16  is manually pushed slightly into housing  14 . The configuration of groove  188  causes pin  192  to move into an outwardly curving second alcove  198 . As jack  16  is manually released, pin  192  slides down a lower side channel  193  back into main channel  186 , thereby allowing jack  16  to freely slide outward into the extended position. The above process can be repeated to selectively move jack  16  between the retracted and extended position. Alternative embodiments of the means for selectively retaining are disclosed in the &#39;401 patent and &#39;017 application which were previously incorporated herein by specific reference. 
     Turning to FIGS. 9 and 10, jack  16  is configured such that when jack  16  is secured to housing  14  as discussed above, center finger  66  of PCB  62  is received within channel  132  of jack  16 . In one embodiment of the present invention, means are provided for effecting electrical communication between media plug  13  and contact  76  on PCB  62  when slide plate  100  is in the extended position and media plug  13  is received within aperture  116  thereof By way of example and not by limitation, depicted in FIG. 9, jack  16  is in the retracted position. In this position, downwardly curved portion  158  of pin  150  is positioned over covered portion  80  of contact  76 . As a result, contact pin  150  is insulated from electrical communication with contact  76 . Also in this position, distal end  58  of center finger  66  is vertically aligned within aperture  116 . This is enabled since in the retracted position, plug  13  is not received within aperture  116 . 
     Depicted in FIG. 10, jack  16  is in the extended position. In this configuration, downwardly curved portion  158  of pin  150  is biased against exposed portion  78  of contact  76  such that pin  150  is in electrical communication with contact  76 . Similarly, depending on the configuration and intended use, other pins  150  can be biased against corresponding contacts formed on PCB  62 . In the extended position, media plug  13  can be selectively received within aperture  116  such that lead end  152  of pin  150  biased against electrical contacts on media plug  13 . As a result, pin  150  facilitates electrical communication between media plug  13  and contact  76  on PCB  62 . Alternative embodiments of the means for effecting electrical communication are set forth in U.S. patent application Ser. No. 09/033,270, filed Mar. 2, 1998 which was previously incorporated herein by specific reference. 
     Although jack  16  including pin assembly  102  are shown used on housing  14 , the present invention also envisions that jack  16  or elements thereof can be used in a variety of different environments. For example, PCB  62  can be formed as a portion of a primary circuit board that is securely mounted within an electrical apparatus. Jack  16  can then be directly and slidably mounted to the electrical apparatus so as to be in communication with the circuit board in the same fashion as discussed above. This embodiment eliminates the need for housing  14 . Based on the teachings set forth herein, it is appreciated that jack  16  or components thereof can be used to replace existing retractable slide plates that currently incorporate the use of a flexible wire ribbon. 
     The inventive assemble have numerous advantages over the prior art. For example, as a result of pin  150  being in electrical communication with contact  76  by biased rather than fixed engagement, jack  16  can be selectively removed and reattached to housing  14  or other comparable structure without damaging the electrical connection. Furthermore, as a result of the shape, length, and the fact that only the tail end  154  of pins  150  are fixed, if at all, pins  150  are effective in minimizing localized stresses due to insertion and removal of media block  13 . Furthermore, since inventive pins  150  produce a relatively long moment arm, lead end  152  of each pin  150  can be resiliently bent by the insertion of media plug  13  without the threat of bending pins  150  beyond their elastic point. 
     FIGS. 12-15 illustrate another preferred embodiment of the contact pin assembly  300 . As shown in the attached figures, the contact pins  302  have a generally S-shaped configuration with a lead end  304  and a tail end  306 . It will be appreciated that the term S-shaped is used broadly to describe any shape of pin in which portions of the pin are curved in opposite directions. 
     The contact pin assembly  300  includes a yoke block  308  disposed proximate the tail end  306  of the contact pins  302  and a central guide  310  disposed proximate the middle portion of the contact pins. As shown in the accompanying figures, yoke block  308  is disposed slightly inwardly from the tail ends  306  of the contact pins  302  such that the proximal ends  312  of the contact pins protrude from the yoke block. The central guide  310  is located near the middle portion  314  of the contact pins  302 , but one skilled in the art will appreciate that the central guide can be disposed in any suitable location between the lead end  304  and tail end  306  of the contact pins  302 . 
     The yoke block  308  and the central guide  310  advantageously keep the pins correctly aligned and in a generally parallel configuration, especially at the tip or lead end  304  of the contact pins  302 . Because the contact pins  302  are correctly aligned, the pins do not touch, overlap or short circuit. Thus, the yoke block  308  and central guide  310  help prevent misalignment and undesirable electrical contact between the contact pins  302 . 
     In greater detail, the central guide  310  is preferably positioned in the middle portion  314  of the contact pin  302  such that the length of the contact pin from the central guide to the lead end  304  is relatively short. Accordingly, the length of the cantilever portion of the contact pin  302  is relatively short and that helps maintain the pin in the correct location. 
     The shape and material properties of the contact pins  302  also help keep the pins in the proper alignment. In particular, the contact pins  302  are constructed from a conductive material, such as metal, that is relatively rigid such that the pins are properly aligned. The contact pins  302  are also constructed from a material that is elastically deformable and able to withstand repeated bending stresses to allow repeated contact with the plug. For example, the contact pins  302  may be constructed from metals or alloys, such as steel, copper, nickel, etc., with suitable characteristics. The contact pins  302  may also be plated with materials such as gold to improve electrical conductivity. The contact pins  302  are preferably stamped or machined into the desired configuration, but the pins may also be molded, pressed, bent, etc. into the desired shape. 
     The yoke block  308  and central guide  310  are constructed from a dielectric or electrically insulating material, such as plastic. The dielectric material used to construct the yoke block  308  and the central guide  310  desirably has sufficient rigidity and strength to hold the contact pins  302  in the proper alignment. The yoke block  308  and central guide  310  can be constructed, for example, from plastic or synthetic materials such as polypropelyne, polyester, polyamide, etc. with suitable characteristics. The yoke block  308  and the central guide  310  are preferably injection molded or machined into the desired shape, but the block and guide may be constructed by any appropriate means. 
     The yoke block  308 , central guide  310  and contact pins  302  can be co-molded as a single unit, or constructed independently and joined together. For example, the yoke block  308  and central guide  310  may be attached to the contact pins  302  by ultrasonic bonding, adhesives, and the like. Advantageously, by forming the yoke block  308 , central guide  310  and contact pins  302  as a single part, that may simplify the manufacturing process and decrease the time required to construct the contact pin assembly  300 . 
     As best seen in FIGS. 14 and 15, the lead end  304  of the contact pins  302  include a downwardly curved distal end  316 . The distal end  316  of the contact pins  302  are downwardly curved to allow the media plug, such as a RJ-11 series connector plug, to be repeatedly inserted and removed from the receiving aperture  116 . The distal end  316  is curved at least about a 45° angle with respect to the contact pin  302  and it has a length of about 1 mm. The distal ends  316  of the contact pins  302  could also be curved at different angles and have other lengths depending, for example, upon the type of plug intended to be used in conjunction with the contact pins. Proximate the distal end  316  is a first elongated section  318 . The elongated section  318  is preferably generally straight and has a length of about 6 mm. 
     The first elongated section  318  is connected to the middle portion  314  by a first angled section  320 . The first angled section  320  joins the elongated section  318  at an angle α which is preferably between about 5° and about 25°, and more preferably about 15°. The middle portion  314  of the contact pin  302  is preferably generally straight and, as discussed above, includes the central guide  310 . The middle portion  314  is about 9 mm in length, and it can include one or more angled or curved sections as desired. The central guide  310  is preferably positioned proximate the midpoint of the middle portion  314 , but the central guide can be located in any desired location of the middle portion or other suitable portion of the contact pins  302 . 
     The middle portion  314  of the contact pin  302  is connected to a second angled section  322  that connects the middle portion to a downwardly curved portion  324 . The second angled section  322  joins the middle portion  314  to the downwardly curved portion  324  at an angle β of between about 5° and about 25°, and more preferably about 10°. The downwardly curved portion  324  includes a first generally straight section  326 , a curved section  328  and a second generally straight section  330 . The first and second generally straight sections  326  and  330  have a length of about 2 mm and 4 mm, respectively. The curved section  328  has an arc angle θ in the range of about 70° to about 90°, and more preferably about 80°. 
     In the preferred embodiment described above, the overall length of the contact pin  302  is between about 10 mm and 25 mm with about 17 mm being more preferred. Additionally, the central guide  310  is located about 8 mm from the yoke block  308  and about 9 mm from the distal end  316 . One skilled in the art will readily appreciate that dimension and configurations of the various components of the contact pin assembly  300  can vary depending upon, for example, the intended use of the contact pin assembly or connector module. Thus, while the dimensions and configurations are given in connection with a preferred embodiment, it will be understood that the pin assembly  300  can have other suitable dimensions and configurations. For example, the contact pin  302  can be longer or shorter, and the angled portions  320  and  322  may have other suitable angles depending, for example, upon the type of plug intended to engage the pins or the size of the connector modular. 
     The yoke block  308  shown in the accompanying figures includes a body  332  with a polygon cross-section and generally cylindrical ends  334  and  336 . The cylindrical ends  334  and  336  allow the yoke block  308  to be pivotally connected to the pin block  350  shown in FIGS. 12 and 13. The yoke block  308 , however, can have any suitable configuration used to connect the contact pin assembly  300  to the pin block  350 . Additionally, the central guide  310  has a generally elliptical cross section with a body  338 , a front wall  340  and a rear wall  342 . The front wall  340  and rear wall  342  are preferably parallel and equidistant from the center of the body  338 . One skilled in the art will appreciate that the guide  310  could have any desirable shape (e.g., square, rectangular, circular, etc.) that would retain the contact pins  302  in the desired configuration and location. 
     As shown in FIGS. 12 and 13, the pin block  350  has generally the same configuration as the pin block  104  described above, except the pin block  350  does not require the elongated slots  168  or insulating walls  170 . The elongated slots  168  and insulating walls  170  are not required because the central guide  310  positions the contact pins  302  in the desired alignment. Advantageously, this simplifies the manufacturing and assembly of the pin block  350 , and the contact pins  302  cannot be incorrectly positioned in the wrong slot. It will be appreciated, however, that the pin block  350  may include elongated slots and insulating walls that extend all or a portion of the length of the pin block. 
     As best seen in FIGS. 12 and 13, the pin block  350  has a generally rectangular configuration with a top surface  352 , right sidewall  354 , left sidewall  356 , back wall  358  and front opening  360 . The pin block  350  also includes a boundary wall  362  positioned near and generally parallel to the back wall  358  to form a compartment  364 . The compartment  364  is sized and configured to receive the yoke block  308 . In particular, the sidewalls  354  and  356  include apertures  366  that are sized and configured to receive the ends  334  and  336  of the yoke block  308  such that the yoke block is retained within the compartment  364 . The sidewalls  354  and  356  of the pin block  350  may also contain apertures that are sized and configured to receive the ends of the central guide  310 , but these apertures are not required. It will be appreciated that the sidewalls  354  and  356  do not require aperture  366  because other suitable means, such as detents or receiving portions, may be used to secure the yoke block  308  and/or central guide  310  in the desired positions. More preferably, the central guide is not attached to the pin block  350  and instead the contact pin assembly  300  is attached to the pin block only by the yoke block  308 . 
     During assembly, the ends  334  and  336  of the yoke block  308  are inserted into the apertures  366  to attach the contact pin assembly  300  to the pin block  350 . As discussed above, the ends  334  and  336  of the yoke block  308  are generally cylindrical to pivotally attach the contact pin assembly  300  to the pin block  350 , but the contact pin assembly can also be non-rotatably attached to the pin block. In addition, the contact pin assembly  300  is attached to the pin block  350  such that at least the lead ends  304  of the contact pins  302  extend into the aperture  116 , and the distal ends  316  are sized and configured to electrically contact the media plug inserted into the aperture. In particular, the curved distal ends  316  of the contact pins  302  electrically communicate with corresponding contacts on the media plug, and the curved distal ends allow the media plug to be repeatedly inserted and removed from the aperture. 
     The central guide  310  is preferably freely disposed between the sidewalls  354  and  356 , and it is not attached to the pin block  350 . In particular, the length of the central guide  310  is preferably slightly less than the length of the body  332  of the yoke block  308 , and slightly less than the distance separating the inner surfaces of the sidewalls  354  and  356  of the pin block  350 . Thus, the yoke block  308  generally keeps the contact pins  302  in the desired longitudinal alignment with the pin block  350 , without rigidly attaching the contact pins to the pin block. 
     In operation, when a media plug is inserted into the aperture  116 , the contact pins  302  are deflected downwardly. The contact pins  302 , for example, may bend at the first angled section  320 , second angled section  322 , downwardly curved portion  324 , or other suitable portions of the pins. Significantly, the central guide  310  keeps the contact pins  302  correctly aligned and spaced to electrically communicate with the corresponding contacts on the media plug. The central guide  310  also allows the contact pins  302  to be constructed from materials with increased stiffness, and that aids in maintaining the contact pins in the desired orientation and positioning within the pin block  350 . In particular, the central guide  310  divides the contact pins  302  into a first portion  370  including the lead end  304  and the first angled section  320 , and a second portion  372  including the tail end  306  and the second angled section  322 . Advantageously, because the second portion  372  is relatively rigid or stiff, the minor flexing of the contact pins  302  within this region results in the elastic bending of the pins. The first portion  370  of the pins  302  is also relatively stiff or rigid, and the bending of this region of the pins is elastic such that it acts like a square spring. When the plug is removed from the aperture  116 , the contact pins  302  resiliently spring back to their original position. 
     The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.