Patent Publication Number: US-2009221171-A1

Title: Multi-pin electrical connector

Description:
BACKGROUND OF THE INVENTION 
     1. Statement of the Technical Field 
     The invention concerns multi-pin electrical connectors. 
     2. Background 
     There are many multi-pin connectors known in the art for joining electrical circuits together. The multi-pin connectors are typically cable mount connectors or board level connectors. Such multi-pin connectors include, but are not limited to, a multi-pin circular connector having a high pin count and a small size. The multi-pin circular connector includes a male connector (or plug) and a female connector (or jack). The male connector is comprised of an electrical pin field encompassed by a housing formed of a wrought material. The term “wrought” as used herein means that a material is forged into a desired form via a hammering process, a twisting process, a bending process, a pressing process and/or other such processes. The electrical pin field is formed of a rear (or bottom) dielectric having electrically conductive pins coupled thereto and a front (or top) dielectric having the electrically conductive pins inserted therethrough. The female connector is comprised of electrically conductive fixed contact field sized and shaped for receiving the electrically conductive pins of the male connector. When the electrically conductive pins are received by the fixed contact field, electrical interconnections are made between two or more electrical circuits. 
     A perspective view of a conventional electrical pin field  100  is provided in  FIG. 1 . It should be noted that the electrical pin field  100  has the front (or top) dielectric removed therefrom for clarity. As shown in  FIG. 1 , the electrical pin field  100  is comprised of a rear (or bottom) dielectric having electrically conductive contacts (not shown). The electrical pin field  100  is also comprised of contact springs and a circular flat gasket with apertures sized and shaped for receiving the contact springs. The contact springs are generally soldered to the electrically conductive contacts (not shown). The circular flat gasket is disposed on the rear (or bottom) dielectric. The electrical pin field is further comprised of electrically conductive pins and pin o-rings. The electrically conductive pins are generally soldered to the contact springs. The pin o-rings are disposed on the electrically conductive pins. The front (or top) dielectric (not shown) has apertures sized and shaped for receiving the electrically conductive pins. The front (or top) dielectric (not shown) is disposed on the circular flat gasket with apertures sized and shaped for receiving the contact springs. 
     As should be understood by those having ordinary skill in the art, in a typical application, the assembled electrical pin field  100  is coined into a multi-pin connector housing (not shown). Multi-pin connector housings are well known to those skilled in the art, and therefore will not be described in herein. The term “coined” as used herein refers to a process of deflecting (or displacing) a material via a mechanical force to captive and/or retain the electrical pin field therein. It should be noted that the housing material is coined (or displaced) approximately ninety degrees (90°). During this coining process, the circular flat gasket expands radially so as to form a seal between the electrical pin field  100  and the multi-pin connector housing (not shown). This seal is an environmental seal configured to prevent moisture from seeping into the electrical pin field  100 . 
     The electrical pin field  100  is known to suffer from certain drawbacks. For example, the electrical pin field  100  is comprised of numerous hand-assembled components. Such hand-assembled components include, but are not limited to, the contact springs, the electrically conductive pins, the flat gasket, the pin  0 -rings and the top insulator. Consequently, the assembly of the electrical pin field  100  is labor intensive, skill intensive, and costly. Also, the multi-pin connector housing (not shown) is coined (or displaced) approximately ninety degrees (90°), which is a relatively large amount of displacement. Such a ninety degree (90°) displacement can generally only be accomplished using a housing comprising a malleable wrought material. Wrought materials are more expensive as compared to other types of housing material, such as essentially unmalleable materials (e.g., cast materials). Furthermore, the seal formed by the radially expanded flat gasket tends to fail over time, and therefore provides an unreliable seal. This failure is due to the gasket stress relieving of the apertures formed in the flat gasket. 
     In view of the forgoing, there remains a need for an electrical pin field having a design that reduces labor and skill intensity, as well as costs associated with the assembly of the electrical pin field. There also remains a need for an electrical pin field that enables an improved coining process. There is further a need for an electrical pin field that provides an improved seal between the electrical pin field and a multi-pin connector housing. 
     SUMMARY OF THE INVENTION 
     This Summary is provided to comply with 37 C.F.R. §1.73, requiring a summary of the invention briefly indicating the nature and substance of the invention. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 
     The invention concerns an electrical pin field. The electrical pin field is comprised of a gasket, a dielectric and two or more electrically conductive pins. The dielectric comprises a support member having a main body with a groove sized and shaped for receiving the gasket. The main body also has a first and second retaining portion sized and shaped for retaining the gasket within the groove. The second retaining portion advantageously has a chamfered edge with a chamfered angle less than ninety degrees (θ&lt;90°), such as a chamfered angle between fifteen and seventy degrees (15°-70°). The electrically conductive pins are integrated within the support member. The term “integrated” as used herein means that an entire surface of an electrically conductive pin is in direct contact with a material forming the support member. It should be noted that a conventional pin field includes electrically conductive pins that are soldered to a support member. 
     According to an aspect of the invention, the electrically conductive pins can be bias ball probes. Each of the electrically conductive pins can have a front end portion, a back end portion, and a main body. The main body can have an angled top portion and at least one indent formed therein. The angled top portion keeps a vertical axis of the electrically conductive pin perpendicular to a plane defined by an injection mold during a molding process. The indent securely seals the electrically conductive pin to the support member during the molding process. The main body is integrated within the support member. The front end portion extends beyond a first surface of the support member. Similarly, the back end portion extends beyond a second surface of the support member that is opposed from the first surface. 
     According to another aspect of the invention, the support member can be further comprised of at least one protruding guide member disposed on a surface of the main body so that it protrudes away from the surface. The protruding guide member can be a solid structure having a cylindrical shape. The protruding guide member assists in an insertion of the electrical pin field into a housing (not shown). The protruding guide member ensures that the electrical pin field is placed in a desired orientation within the housing (not shown). 
     According to yet another aspect of the invention, the support member can be comprised of a protruding portion sized and shaped for preventing the electrical pin field from rotating in the housing (not shown). The protruding portion can have two or more cavities formed therein. The cavities can be sized and shaped for protecting the electrically conductive pins from over deflection when a pushing force is applied thereto. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments will be described with reference to the following drawing figures, in which like numerals represent like items throughout the figures, and in which: 
         FIG. 1  is a perspective view of an electrical pin field of a conventional multi-pin circular connector. 
         FIG. 2  is a perspective view of an electrical pin field of a multi-pin connector that is useful for understanding the invention. 
         FIG. 3A  is a side view of the electrical pin field of  FIG. 2 . 
         FIG. 3B  is a side view of the electrical pin field of  FIG. 2 . 
         FIG. 4  is a top view of the electrical pin field of  FIG. 2 . 
         FIG. 5  is a bottom view of the electrical pin field of  FIG. 2 . 
         FIG. 6  is a cross-sectional view of the electrical pin field taken along line  6 - 6  of  FIG. 4 . 
         FIG. 7  is a cross-sectional view of the electrical pin field taken along line  7 - 7  of  FIG. 4 . 
         FIG. 8  is a flow of diagram of an injection molding process used to make the electrical pin field of  FIG. 2 . 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 2  is a perspective view of an electrical pin field  200  that is useful for understanding the invention. The electrical pin field  200  is generally used in multi-pin connecter systems. The electrical pin field  200  is shown generally by a plurality of electrically conductive pins  202  integrated or integrally molded within a support member  204 . As shown in  FIG. 2 , the electrical pin field  200  is comprised of sixteen ( 16 ) regularly spaced electrically conductive pins  202 . However, the invention is not limited in this regard. For example, the electrical pin field  200  can include any number of electrically conductive pins in any arrangement selected in accordance with a particular multi-pin connector application. 
     Referring again to  FIG. 2 , the electrically conductive pins  202  are of the same type and have a cylindrical shape. For example, the electrically conductive pins  202  comprise bias ball probes available from IDI Corporation of Kansas City, Kans. A bias ball probe includes a chamber with a spring, an inclined plane and a ball disposed therein. When the bias ball probe is actuated, the spring applies a force on the inclined plane. In turn, the inclined pane applies a pushing force on the ball so that the ball rolls against an internal surface of the chamber. In effect, the bias ball probe provides a more robust electrical connection between a front end portion  208  of the pin assembly and the back end portion  210  of the pin assembly as compared to the conventional pin field  100  described above (in relation to  FIG. 1 ). However, the invention is not limited in this regard. 
     Referring again to  FIG. 2 , the support member  204  securely retains the electrically conductive pins  202  in a pre-defined position. In this regard, it should be understood that the electrically conductive pins  202  are arranged in a parallel type configuration. Each of the electrically conductive pins  202  is also arranged so that its vertical axis  212  is generally perpendicular to a plane defined by a surface  206  of the support member  204 . 
     The support member  204  can be a single piece molded component having electrically conductive pins  202  integrated therein. The support member  204  is generally formed from a dielectric material. Such dielectric materials include, but are not limited to, low shrink rate liquid crystal polymers, low shrink rate rubbers and low shrink rate plastics. The support member  204  can be formed utilizing any suitable process known in the art. Such processes include, but are not limited to, molding processes and deposition-etch back processes. 
     According to an embodiment of the invention, the support member  204  is formed utilizing an injection molding process. A flow diagram of an exemplary injection molding process  800  is provided in  FIG. 8 . As shown in  FIG. 8 , the injection molding process  800  generally involves the steps of: ( 802 ) manually placing the electrically conductive pins  202  in a bottom portion of an injection mold tool; ( 804 ) placing a top portion of the injection mold tool on the bottom portion of the injection mold tool; ( 806 ) applying a downward force on the top portion of the injection mold tool; ( 808 ) injecting a material through a gate of the injection mold tool; ( 810 ) waiting a pre-defined period of time; and ( 812 ) removing the support member  204  from the injection mold tool. At least a portion of the electrically conductive pins  202  are integrated or integrally molded within the support member  204 . The invention is not limited in this regard and may be formed using any other suitable process. 
     Referring now to  FIGS. 3A-3B , there are provided side views of the electrical pin field  200 . As shown in  FIGS. 3A-3B , the electrically conductive pins  202  are partially disposed in the support member  204 . In effect, a first end portion (or contact portion)  306  of each pin  202  extends beyond a first surface  302  of the support member  204 . Similarly, a second end portion (or a solder portion)  308  of each pin  202  extends beyond a second surface  304  of the support member  204 . The first end portions  306  are provided to mate with electrically conductive contacts of a female connector (not shown) for joining two or more electrical circuits together. The second end portions  308  can have a shape suitable for enabling the connection of wires to the pins  202  via a soldering process. Such shapes include, but are not limited to, solid cylindrical shapes, solid square turret shapes, and cup shapes. Soldering processes are well known to those skilled in the art, and therefore will not be described in detail herein. 
     The support member  204  shown is comprised of a main body member  320  and a protruding end member  322 . The main body member  320  has a groove  310 , a first retaining portion  316  and a second retaining portion  318 . The groove  310  is sized and shaped for receiving a gasket  312  having a loop-like shape and a central aperture. The retaining portions  316 ,  318  are sized and shaped for preventing the gasket  312  from being dislodged from the groove  310 . 
     According to an embodiment of the invention, the gasket is an o-ring gasket. In such a scenario, the groove  310  is an o-ring groove sized and shaped to receive the o-ring gasket. Still, the invention is not limited in this regard. 
     The second retaining portion  318  is advantageously comprised of a chamfered edge  314 . The chamfered edge  314  generally enables an improved coining process by reducing the amount of deflection required to captivate the electrical pin field  200  in a multi-pin connector housing (not shown). Multi-pin connector housings are well known to those skilled in the art, and therefore will not be described in great detail herein. However, it should be understood that any housing suitable for a particular multi-pin connector application can generally be used without limitation. 
     As described above, the phrase “coining process” as used herein refers to a process of deflecting (or displacing) a housing material via a mechanical force to captive and/or retain the electrical pin field  200  therein. It should be noted that the chamfered edge  314  enables a displacement of the housing material by an amount substantially less than ninety degrees (90°). More particularly, the chamfered edge  314  can for example enable a displacement of the housing material by fifteen to seventy degrees (15°-70°). Such a displacement can be accomplished using a housing (not shown) comprising a malleable wrought material as well as other less expensive materials. Such less expensive materials include, but are not limited to, cast materials and other less malleable materials. 
     Referring again to  FIGS. 3A-3B , the gasket  312  is configured to provide a piston seal between the electrical pin field  200  and a multi-pin connector housing (not shown). According to an embodiment of the invention, the gasket  312  is selected to comprise silicon having a hardness between fifty (50) to ninety (90) durometers. Still, the invention is not limited in this regard. It should be understood that this piston seal is an environmental seal configured to prevent moisture from seeping into the electrical pin field  200 . It should also be understood that the piston seal formed by the gasket  312  is more reliable than the seal formed by the flat gasket of a conventional electrical pin field  100 . Stated differently, the piston seal generally lasts longer as compared to the conventional flat gasket seal described above in relation to  FIG. 1 . 
     Referring now to  FIG. 4 , there is provided a top view of the electrical pin field  200 . As shown in  FIG. 4 , the electrically conductive pins  202  are arranged in a grid pattern  406 . The grid pattern  406  has a plurality of parallel rows  408  and a plurality of parallel columns  410 . Each of the rows  408  and columns  410  includes numerous electrically conductive pins  202  that are equally spaced apart. For example, if the electrical pin field  200  is to be used in a nine (9) pin electrical connector application, then the electrical pin field  200  is comprised of three (3) rows  408  having three (3) equally spaced apart electrically conductive pins  202 . Similarly, each of the columns  410  includes three (3) equally spaced apart electrically conductive pins  202 . As described above, the invention is not limited with respect to the number or arrangement of the electrically conductive pins  202 . 
     Referring again to  FIG. 4 , the support member  204  also includes one or more protruding guide members  404 . The protruding guide members  404  assist in the insertion of the support member  204  into a multi-pin connector housing (not shown). The protruding members  404  also ensure that the electrical pin field  200  is placed in a proper orientation within the multi-pin connector housing (not shown). The protruding guide members  404  can further ensure that the support member  204  is spaced a pre-defined distance from a surface of a printed circuit board (PCB). In one embodiment, the protruding guide members  404  have a solid cylindrical shape. Still, the invention is not limited in this regard. For example, the protruding guide members  404  can have any solid or tubular shape selected in accordance with a particular electrical pin field  200  application. 
     Referring now to  FIG. 5 , there is provided a bottom view of the electrical pin field  200 . As shown in  FIG. 5 , the support member  204  is comprised of a protruding member  322 . The protruding member  322  has a rectangular shape with rounded edges  502 . The protruding member  322  is provided to ensure that the electrical pin field  200  remains in a selected or optimal position within a multi-pin connector housing (not shown). Stated differently, the protruding member  322  is provided to guarantee that each of the electrically conductive pins  202  mate with the respective electrically conductive socket of a female connector (not shown). More particularly, the protruding member  322  provides a means for preventing the electrical pin field  200  from rotating or spinning inside a multi-pin connector housing (not shown). 
     Referring again to  FIG. 5 , the protruding member  322  has a pre-defined width  506  and length  504 . For example, the width  506  and length  504  are selected to have the same value. In one particular embodiment, each of the dimensions  504 ,  506  is selected to have a value falling within the range of 0.348 inch to 0.352 inch. However, other width and length dimensions may be used. 
     The protruding member  322  also has a plurality of cavities  508  formed therein. The cavities  508  are provided to protect the electrically conductive pins  202  from over deflection when a pushing force is applied thereto. The cavities  508  are arranged in a grid pattern  520 . The grid pattern  520  includes a plurality of parallel rows  510  and a plurality of parallel columns  512 . Each of the rows  510  and columns  512  shown includes numerous cavities  508  that are equally spaced apart. For example, if the electrical pin field  200  is to be used in a nine pin electrical connector application, then the electrical pin field  200  can comprise three rows  510  having three equally spaced apart cavities  508 . Similarly, each of the columns  512  shown includes three equally spaced apart cavities  508 . Still, the invention is not limited in this regard. 
     Referring now to  FIG. 6 , there is provided a cross sectional view of the electrical pin field  200  taken along line  6 - 6  of  FIG. 5 . As shown in  FIG. 6 , the main body member  320  is comprised of a first surface  302  with the cavities  502  formed therein. Each of the cavities  502  has a pre-selected diameter  604 . For example, each of the diameters  604  can be selected to have a value equal to 0.072 inches. Still, the invention is not limited in this regard. Notably, the cavities  502  are provided to protect the electrically conductive pins  202  from over deflection when a pushing force is applied thereto. As such, the cavities  502  can be designed in accordance with a particular electrical pin field  200  application. 
     The main body member  320  has a pre-selected height  610 . For example, in one present embodiment, the height  610  is selected to have a value falling within the range of 0.212 inch to 0.228 inch. Still, the invention is not limited in this regard. Similarly, in one present embodiment, the protruding member  322  has a pre-selected height  612 . For example, the height  612  is selected to have a value falling within the range of 0.102 inch to 0.118 inch. Still, the invention is not limited in this regard. 
     As shown in  FIG. 6 , each of the electrically conductive pins  202  has a main body  624  with an angled top portion  626  and at least one indented (or recessed) portion  620 . The angled top portion  626  can help keep the vertical axis  212  of the electrically conductive pin  202  perpendicular to a plane defined by an injection mold tool (not shown) in the case of a molding process. The indented portions  620  can assist in sealing the electrically conductive pins  202  to the molding material during a molding process. The indented portion  620  can have any shape selected in accordance with a particular electrical pin field  200  application. For example, the indented portion  620  can have a surface  622  that is perpendicular to the vertical axis  212  of the respective electrically conductive pin  202 . Alternatively, the indented portion  620  can have a sloped surface  622  that is set at an angle with respect to the vertical axis  212  of the respective electrically conductive pin  202 . Notably, such a sloped surface configuration generally has improved environmental sealing capabilities as compared to the non-sloped configuration. 
     Referring now to  FIG. 7 , there is provided a cross sectional view of the electrical pin field  200  taken along line  7 - 7  of  FIG. 5 . As shown in  FIG. 7 , each of the first and second retaining portions  316 ,  318  of the support member  204  has a pre-selected diameter  702 . For example, in one present embodiment, the diameter  702  is selected to have a value falling within the range of 0.522 inch to 0.524 inch. Still, the invention is not limited in this regard. Each of the protruding guide members  404  also has a diameter  704  selected in accordance with a particular pin field application. For example, in one present embodiment, the diameter  704  is selected to have a value falling within the range of 0.192 inch to 0.208 inch. Still, the invention is not limited in this regard. 
     The portion of the main body member  320  having the groove  310  formed therein has a diameter  706 . The diameter  706  is selected in accordance with a particular groove  310  application. For example, in one present embodiment, the diameter  706  is selected to have a value falling within the range of 0.452 inch to 0.456 inch. Still, the invention is not limited in this regard. The chamfered edge  314  of the main body member  320  is selected to have a width  708  and a chamfered angle  710 . The chamfered angle  710  can have a value between fifteen and seventy degrees (15°-70°). According to a particular embodiment of the invention, the width  708  is selected to have a value falling within the range of 0.010 inch to 0.020 inch. The chamfered angle  710  is selected to be thirty degrees (30°). Still, the invention is not limited in this regard. 
     All of the apparatus, methods and algorithms disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure. While the invention has been described in terms of preferred embodiments, it will be apparent to those of skill in the art that variations may be applied to the apparatus, methods and sequence of steps of the method without departing from the concept, spirit and scope of the invention. More specifically, it will be apparent that certain components may be added to, combined with, or substituted for the components described herein while the same or similar results would be achieved. All such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope and concept of the invention as defined. 
     The Abstract of the Disclosure is provided to comply with 37 C.F.R. §1.72(b), requiring an abstract that will allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the following claims.