Abstract:
Circuit board transformer components include a bobbin having at least one ground pin with a board pin portion and a component ground section extending substantially perpendicular to the board pin portion. The component ground section is secured to a magnetic piece or the bobbin to address electromagnetic interference in a power supply application. The components are manufacturable with a reduced number of steps and greater uniformity with improved performance characteristics.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation application of International Application No. PCT/US2014/032445, which claims priority to Chinese Patent Application No. 201310225848.X filed Apr. 7, 2013. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The field of the invention relates generally to the manufacture of magnetic components, and more specifically to the manufacture of transformer devices having integrated grounding structure for circuit board applications. 
         [0003]    Magnetic components such as inductors and transformers are now in widespread use in power supply applications for electronic devices. Transformer devices for circuit board applications are known and include primary and secondary transformer coils wound on an insulative bobbin including conductive pins to establish electrical connections in corresponding through-holes of a circuit board. The bobbin and associated coils are coupled to a magnetic core assembly, and according to well-known principles, the coils of the transformer can be used to increase or decrease a voltage input to provide a power supply output at a different voltage than the input voltage. Thus, for example, a higher voltage input can be stepped down to a lower voltage input suitable for use by the electronics on the circuit board, or a lower voltage output from the electronics on the circuit board can be stepped to a higher voltage that is input to another electrical device. 
         [0004]    Electromagnetic interference (EMI) issues are problematic in certain applications of such transformers and corresponding improvements are desired. It is known in the art to connect a wire to the magnetic core on one end and to connect the wire to an electrically quiet node at is opposite end. One end of wire is typically connected to a conductive pin provided on the bobbin that is connected through the circuit board assembly to the quiet electrical node when the transformer is installed on the circuit board, and the other end of this wire is electrically connected to the magnetic core using conductive epoxy. Such a wire assembly process to address EMI issues is, however, complicated and time consuming. It is also subject to reliability issues and performance issues presented by varying grounding resistance as the components are used. In particular, lower grounding resistance is preferred but the actual grounding resistance is difficult to control from a manufacturing perspective. As a result, the core to pin resistance must be tested, leading to an increased cost of providing the transformer components. 
         [0005]    U.S. Pat. No. 8,198,969 teaches a transformer component having a ground pin provided in a pocket of a bobbin, and exposing an end of the ground pin to a surface of the magnetic core. The magnetic core may be formed with a groove to receive the pin, and the pin and the core may be electrically connected with a conductive adhesive. While this construction represents considerable improvements over the wire assembly process described above, it is not completely satisfactory from a manufacturing perspective and improvements are desired. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    Non-limiting and non-exhaustive embodiments are described with reference to the following Figures, wherein like reference numerals refer to like parts throughout the various drawings unless otherwise specified. 
           [0007]      FIG. 1  is a front perspective view of a first exemplary core piece for an exemplary circuit board transformer component according to a first exemplary embodiment of the present invention. 
           [0008]      FIG. 2  is a top view of the exemplary core piece shown in  FIG. 1 . 
           [0009]      FIG. 3  is a bottom perspective view of an exemplary bobbin including a ground pin for use with the core piece shown in  FIGS. 1 and 2 . 
           [0010]      FIG. 4  is a side view of the exemplary bobbin and ground pin shown in  FIG. 3 . 
           [0011]      FIG. 5  is a perspective view of the bobbin being assembled with a magnetic core assembly including the core piece shown in  FIGS. 1 and 2 . 
           [0012]      FIG. 6  is a bottom view of the assembly shown in  FIG. 5  and illustrating a connection of the ground pin to the core. 
           [0013]      FIG. 7  is similar to  FIG. 6  but illustrates another stage of manufacture wherein the ground pin is adhered in place using a conductive epoxy. 
           [0014]      FIG. 8  is a rear perspective view of the assembly shown in  FIGS. 7 and 8  at another stage of manufacture wherein the transformer component is cured. 
           [0015]      FIG. 9  is a top plan view of an exemplary bobbin including a ground pin according to a second exemplary embodiment of the present invention. 
           [0016]      FIG. 10  is a front perspective view of the bobbin shown in  FIG. 9 . 
           [0017]      FIG. 11  is a front perspective view of a magnetic core piece for use with the bobbin shown in  FIGS. 9 and 10 . 
           [0018]      FIG. 12  is a top plan view of the magnetic core piece shown in  FIG. 9 . 
           [0019]      FIG. 13  is a perspective view of the bobbin shown in  FIGS. 8 and 9  being assembled the magnetic core piece shown in  FIGS. 11 and 12  and illustrating a connection of the ground pin to the core. 
           [0020]      FIG. 14  is a view similar to  FIG. 13  but showing a second magnetic core piece in the assembly. 
           [0021]      FIG. 15  is view similar to  FIG. 14  but illustrating another stage of manufacture wherein the ground pin is adhered in place using a conductive epoxy. 
           [0022]      FIG. 16  is a view similar to  FIG. 15  but illustrating the component at another stage of manufacture wherein the transformer component is cured. 
           [0023]      FIG. 17  is a front perspective view of a magnetic core piece according to a third exemplary embodiment of the present invention. 
           [0024]      FIG. 18  is a top plan view of the magnetic core piece shown in  FIG. 17 . 
           [0025]      FIG. 19  is a front perspective view of an exemplary bobbin including a ground pin for use with the magnetic core piece shown in  FIGS. 17 and 18 . 
           [0026]      FIG. 20  is a side elevational view of the exemplary bobbin shown in  FIG. 19 . 
           [0027]      FIG. 21  is a perspective view of the bobbin shown in  FIGS. 19 and 20  being assembled with a magnetic core assembly including the core piece shown in  FIGS. 17 and 18  and illustrating a connection of the ground pin to the magnetic core piece. 
           [0028]      FIG. 22  is a view similar to  FIG. 21  but illustrating another stage of manufacture wherein the ground pin is adhered in place using a conductive epoxy. 
           [0029]      FIG. 23  is a side view of the assembly shown in  FIG. 21  illustrating a connection of the ground pin to the magnetic core piece. 
           [0030]      FIG. 24  is a side view of the assembly shown in  FIG. 22  component at another stage of manufacture wherein the wherein the ground pin is adhered in place using a conductive epoxy. 
           [0031]      FIG. 25  is a front perspective view of a magnetic core piece according to a fourth exemplary embodiment of the present invention. 
           [0032]      FIG. 26  is a top plan view of the magnetic core piece shown in  FIG. 25 . 
           [0033]      FIG. 27  is a rear perspective view of an exemplary bobbin including a ground pin for use with the magnetic core piece shown in  FIGS. 25 and 26 . 
           [0034]      FIG. 28  is a bottom view of the exemplary bobbin shown in  FIG. 27 . 
           [0035]      FIG. 29  is rear perspective view of the bobbin shown in  FIG. 27  and illustrating a connection of the ground pin to the bobbin 
           [0036]      FIG. 30  illustrates the bobbin shown in  FIG. 29  being assembled with the magnetic core piece shown in  FIGS. 25 and 26 . 
           [0037]      FIG. 31  illustrates the assembly of  FIG. 31  provided with a second magnetic core piece. 
           [0038]      FIG. 32  is a comparative ground resistance chart of conventional transformer components and components fabricated in accordance with embodiments of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0039]    Exemplary embodiments of circuit board transformer components are described herein that simplify the grounding structure to address EMI concerns, enhance reliability of the manufactured components, and achieve better grounding performance (i.e., lower the grounding resistance of manufactured components relative to known components of the type described above). Method aspects will be in part apparent and in part explicitly discussed in the following description. 
         [0040]      FIGS. 1-8  collectively illustrate a first exemplary embodiment of a circuit board transformer component  200  ( FIGS. 4-6 ) generally including a bobbin  102  that is separately illustrated in  FIGS. 3 and 4 ) and a magnetic body  104  fabricated from a first magnetic piece  106  that is separately illustrated in  FIGS. 1 and 2 , and a second magnetic piece  108 . 
         [0041]    Referring now to  FIGS. 1 and 2 , the first magnetic piece  106  generally includes a generally flat or planar base  110  and upstanding side walls  112 ,  114 , and  116  extending upwardly from the base. The sidewalls  112 ,  114 ,  116  are generally straight and rectilinear on their exterior but are round on the interior to define a substantially semicircular interior recess or receptacle  118  above the base  110 . A round projection  120  extends upwardly from the base  110  in a central portion of the receptacle  118 . In the example shown, the periphery of the projection  120  is generally circular and completes a 360° arc on the base  110 , while the receptacle  118  is open sided and completes much less than a 360° arc above the base  110 . 
         [0042]    A front edge  122  of the base  110  is exposed and in the example shown includes a groove  124  and a tapered side edge  126 . The tapered side edge  126  imparts a triangular-shaped or wedge-shaped front corner adjacent the front edge  122 . The opposite corner of the front edge  122  as shown does not include a tapered corner such as the side edge  126 . The side walls  112  and  114  further include exposed front surfaces  128 ,  130  extending above the front edge  122  of the base  110 . The front edge  122  of the base  110  may also be chamfered as shown to assist with seating of the bobbin  102  in a desired position and orientation. 
         [0043]    The core piece  106  may be fabricated from a known magnetic material according to known processes. The core piece  108  ( FIGS. 4-8 ) may be fabricated as essentially an identical piece to the core piece  106  in contemplated embodiments. It is noted, however, that the groove  124  may be considered optional in the core piece  108  and need not be included. 
         [0044]    Referring now to  FIGS. 3 and 4 , the bobbin  102  is fabricated from an electrically nonconductive or insulative material and generally includes an upper flange  140 , a tubular body  142 , a lower flange  144  and a connecting portion  146 . The flanges  140 ,  144  define a winding space  148  to accommodate a primary winding or coil and a secondary winding or coil according to known methods and techniques. The coils or windings are terminated or connected to one of a plurality of electrically conductive pins  150 ,  152 ,  154 ,  156  provided in the connecting portion  146 . The pins  150 ,  152 ,  154 ,  156  generally extend downwardly from the connecting portion  146  and generally parallel to a longitudinal axis  158  of the tubular portion  142 . 
         [0045]    One of the pins, namely the pin  152  in the example of  FIGS. 3 and 4 , is a ground pin and includes an axial pin board portion  160  extending generally parallel to the axis  158  and the other pins  150 ,  154 ,  156  for connection to a circuit board via a through-hole therein, and a component ground portion  162  extending generally perpendicular to the axis  158  and the other pins  150 ,  154 ,  156 . In other words, and unlike the other pins  150 ,  154 ,  156 , the ground pin  152  includes a right angle bend with the ground portion  162  extending from one side of the right angle bend and the pin board portion  160  extending from the other side of the right angle bend. As such, the ground portion  162  extends perpendicularly from a vertical side wall  164  of the connecting portion  146  as best shown in  FIG. 4 , while the pin board portion  160  extends perpendicularly from a bottom wall  166  of the connecting portion  146 . The right angle bend facilitates the connection of the ground pin  152  to the core piece  106  as further explained below. The other pins  150 ,  154 ,  156  are substantially straight and do not include a right angle bend. 
         [0046]    The flanges  140 ,  144  each include a central opening  168  communicating with a hollow interior of the tubular portion  142 . The central opening  168  cooperates with the projections  120  of the magnetic core piece  106  ( FIGS. 1 and 2 ) when the bobbin  102  is assembled to the core piece  106 . 
         [0047]    As shown in  FIG. 5 , the bobbin  102  may be sandwiched between the core pieces  106  and  108 , using the openings  168  ( FIG. 3 ) in the bobbin  102  and the projections  120  ( FIGS. 1 and 2 ) in the core pieces  106  and  108  to guide the pieces into the proper orientation. The magnetic core pieces  106  and  108  may be gapped from one another when assembled to the bobbin  102  in any manner known in the art. 
         [0048]    As best shown in  FIG. 6 , as the bobbin  102  is assembled to the core piece  106 , the component ground portion  162  of the ground pin  152  becomes received in the groove  124  at the core piece front edge  122 . 
         [0049]      FIG. 7  shows a conductive epoxy  170  being applied to the groove  124  as the component ground portion  162  is mated with the groove. As shown in  FIG. 8 , the component ground portion  162  is secured in the groove  124  with the conductive epoxy and the entire component  100  is baked to cure. 
         [0050]    The connection of the component ground portion  162  and the core piece  106  via the groove  124  may be reliably accomplished in fewer manufacturing steps and at comparatively lower cost than has conventionally been provided. 
         [0051]      FIGS. 9-16  collectively illustrate a second exemplary embodiment of a circuit board transformer component  200  ( FIGS. 13-16 ) generally including a bobbin  202  that is separately illustrated in  FIGS. 9 and 10 ) and a magnetic body  204  fabricated from a first magnetic piece  206  that is separately illustrated in  FIGS. 11 and 12 , and a second magnetic piece  208 . 
         [0052]    Referring now to  FIGS. 11 and 12 , the first magnetic piece  206  generally includes a generally flat or planar base  110  and upstanding side walls  112 ,  114 , and  116  extending upwardly from the base  110 . The sidewalls  112 ,  114 ,  116  are generally straight and rectilinear on their exterior but are round on the interior to define a substantially semicircular interior recess or receptacle  118  above the base  110 . A round projection  120  extends upwardly from the base  110  in a central portion of the receptacle  118 . In the example shown, the periphery of the projection  120  is generally circular and completes a 360° arc on the base  110 , while the receptacle  118  is open sided and completes much less than a 360° arc above the base  110 . 
         [0053]    A front edge  122  of the base  110  is exposed and unlike the core piece  106  ( FIGS. 1 and 2 ) in the example core piece  206  as shown the groove  124  and the tapered side edge  126  are omitted. The front edge  122  of the base  110  in the core piece  106  is entirely straight and linear, and in the example shown may also be chamfered as shown to assist with seating of the bobbin  202  in a desired position and orientation. 
         [0054]    The core piece  206 , like the core piece  106  may be fabricated from a known magnetic material according to known processes. The core piece  208  ( FIGS. 14-16 ) may be fabricated as essentially an identical piece to the core piece  206  in contemplated embodiments. 
         [0055]    Referring now to  FIGS. 9 and 10 , the bobbin  202  is fabricated from an electrically nonconductive or insulative material and generally includes an upper flange  240 , a tubular body  242 , a lower flange  244  and a connecting portion  246 . The flanges  240 ,  244  define a winding space  248  to accommodate a primary winding or coil and a secondary winding or coil according to known methods and techniques. The coils or windings are terminated or connected to one of a plurality of electrically conductive pins  250 ,  252 ,  254 ,  256  provided in the connecting portion  246 . The pins  250 ,  252 ,  254 ,  256  generally extend downwardly from the connecting portion  246  and generally parallel to a longitudinal axis (not shown in  FIG. 10  but similar to the axis  158  shown in  FIG. 4 ). 
         [0056]    One of the pins, namely the pin  250  in the example of  FIGS. 9 and 10 , is a ground pin and includes an axial pin board portion  260  extending generally parallel to the axis of the other pins  252 ,  254 ,  256  for connection to a circuit board via a through-hole therein, and a component ground portion  262  extending generally perpendicular to the axis of the other pins  252 ,  254 ,  256 . In other words, and unlike the other pins  252 ,  254 ,  256 , the ground pin  250  includes a right angle bend with the ground portion  262  extending from one side of the right angle bend and the pin board portion  260  extending from the other side of the right angle bend. As such, the ground portion  262  in the example shown in  FIGS. 9 and 10  extends parallel to a horizontal upper wall  264  of the connecting portion  246 , while the pin board portion  260  extends perpendicularly from a bottom wall  266  of the connecting portion  246 . The right angle bend facilitates the connection of the ground pin  250  to the core piece  206  as further explained below. 
         [0057]    The flanges  240 ,  244  each include a central opening  268  communicating with a hollow interior of the tubular portion  242 . The central opening  268  cooperates with the projections  120  of the magnetic core piece  206  ( FIGS. 11 and 12 ) when the bobbin  102  is assembled to the core piece  106 . 
         [0058]    As shown in  FIG. 13 , the bobbin  202  may be assembled with the core piece  206 , and as shown in  FIG. 14 , the second core piece  208  is also assembled so that the bobbin  202  is sandwiched between the core pieces  206  and  208 , using the openings  268  ( FIG. 10 ) in the bobbin  202  and the projections  120  ( FIGS. 11 and 12 ) in the core pieces  206  and  208  to guide the pieces into the proper orientation. The magnetic core pieces  206  and  208  may be gapped from one another when assembled to the bobbin  202  in any manner known in the art. 
         [0059]    As shown in  FIGS. 13 and 14 , as the bobbin  202  is assembled to the core piece  206 , the component ground portion  262  is exposed on the upper wall  264  of the bobbin connecting portion  246 , and the component ground portion  262  of the ground pin  250  extends to the vertical face  128  of the sidewall  112  of the magnetic core piece  206 . 
         [0060]      FIG. 15  shows a conductive epoxy  270  being applied to the secure the component ground portion  262  in place and ensure electrical connection to the core piece  102 . As shown in  FIG. 16 , the entire component  200  is then baked to cure the construction. 
         [0061]    In comparison to the first exemplary embodiment, the connection of the component ground portion  262  and the core piece  206  may be reliably accomplished in fewer manufacturing steps and at comparatively lower cost than has conventionally been provided, while providing a slightly simpler shape to the magnetic core piece  206  and also while using a different one of the pins provided on the bobbin  202  as the ground pin. 
         [0062]      FIGS. 17-24  collectively illustrate a third exemplary embodiment of a circuit board transformer component  300  ( FIGS. 21-24 ) generally including a bobbin  302  that is separately illustrated in  FIGS. 19 and 20  and a magnetic body  304  fabricated from a first magnetic piece  306  that is separately illustrated in  FIGS. 17 and 18 , and a second magnetic piece  308 . 
         [0063]    Referring now to  FIGS. 17 and 18 , the first magnetic piece  306  generally includes a generally flat or planar base  110  and upstanding side walls  112 ,  114 , and  116  extending upwardly from the base. The sidewalls  112 ,  114 ,  116  are generally straight and rectilinear on their exterior but are round on the interior to define a substantially semicircular interior recess or receptacle  118  above the base  110 . A round projection  120  extends upwardly from the base  110  in a central portion of the receptacle  118 . In the example shown, the periphery of the projection  120  is generally circular and completes a 360° arc on the base  110 , while the receptacle  118  is open sided and completes much less than a 360° arc above the base  110 . 
         [0064]    A front edge  122  of the base  110  is exposed and in the example shown includes a tapered side edge  126  similar to the core piece  106  ( FIGS. 1 and 2 ) but not a groove  124  as in the core piece  106 . The tapered side edge  126  imparts a triangular-shaped or wedge-shaped front corner adjacent the front edge  122 . The opposite corner of the front edge  122  as shown does not include a tapered corner such as the side edge  126 . The side walls  112  and  114  further include exposed front surfaces  128 ,  130  extending above the front edge  122  of the base  110 . The front edge  122  of the base  110  may also be chamfered as shown to assist with seating of the bobbin  302  in a desired position and orientation. 
         [0065]    The core piece  306  may be fabricated from a known magnetic material according to known processes. The core piece  308  ( FIGS. 21-24 ) may be fabricated as essentially an identical piece to the core piece  306  in contemplated embodiments. 
         [0066]    Referring now to  FIGS. 19 and 20 , the bobbin  302  is fabricated from an electrically nonconductive or insulative material and generally includes an upper flange  340 , a tubular body  342 , a lower flange  344  and a connecting portion  346 . The flanges  340 ,  344  define a winding space  348  to accommodate a primary winding or coil and a secondary winding or coil according to known methods and techniques. The coils or windings are terminated or connected to one of a plurality of electrically conductive pins  350 ,  352 ,  354 ,  356  provided in the connecting portion  346 . The pins  350 ,  352 ,  354 ,  356  generally extend downwardly from the connecting portion  346  and generally parallel to a longitudinal axis  358  of the tubular portion  342 . 
         [0067]    Unlike the others, one of the pins, namely the pin  356  in the example of  FIGS. 19 and 20 , is a ground pin and includes an axial pin board portion  360  extending generally parallel to the axis  358  and the other pins  350 ,  354 ,  356  for connection to a circuit board via a through-hole therein, and a component ground portion  362  extending generally perpendicular to the axis  358  and the other pins  350 ,  352 ,  354 . In other words, the ground pin  356  includes a right angle bend with the ground portion  362  extending from one side of the right angle bend and the pin board portion  360  extending from the other side of the right angle bend. As such, the ground portion  362  extends perpendicularly from a vertical side wall  164  of the connecting portion  146  as best shown in  FIG. 20 , while the pin board portion  360  extends perpendicularly from a bottom wall  166  of the connecting portion  146 . The right angle bend facilitates the connection of the ground pin  152  to the core piece  106  as further explained below. Unlike the previous embodiments the ground portion  362  in the component  300  extends exterior and generally alongside a side wall  168  of the bobbin connector portion  146 . 
         [0068]    The bobbin flanges  340 ,  344  each include a central opening  368  communicating with a hollow interior of the tubular portion  342 . The central opening  368  cooperates with the projections  120  of the magnetic core piece  306  ( FIGS. 17 and 18 ) when the bobbin  302  is assembled to the core piece  306 . 
         [0069]    As shown in  FIG. 21 , the bobbin  302  may be sandwiched between the core pieces  306  and  308 , using the openings  368  ( FIG. 19 ) in the bobbin  302  and the projections  120  ( FIGS. 17 and 18 ) in the core pieces  306  and  308  to guide the pieces into the proper orientation. The magnetic core pieces  306  and  308  may be gapped from one another when assembled to the bobbin  302  in any manner known in the art. 
         [0070]    As best shown in  FIGS. 21 and 23 , as the bobbin  302  is assembled to the core piece  306 , the component ground portion  362  of the ground pin  356  extends toward the side wall  130  of the core piece  306 . 
         [0071]      FIGS. 23 and 24  show a conductive epoxy  370  being applied to secure the component ground portion  362  of the ground pin  356  and complete the electrical connection to the core piece  306 . The entire component  300  is baked to cure to cure the construction. 
         [0072]    In comparison to the first exemplary embodiment, the connection of the component ground portion  362  and the core piece  306  may be reliably accomplished in fewer manufacturing steps and at comparatively lower cost than has conventionally been provided, while providing a slightly simpler shape to the magnetic core piece  306  and also while using a different one of the pins provided on the bobbin  302  as the ground pin. 
         [0073]      FIGS. 26-31  collectively illustrate a fourth exemplary embodiment of a circuit board transformer component  400  ( FIGS. 29-31 ) generally including a bobbin  402  that is separately illustrated in  FIGS. 27 and 28 ) and a magnetic body  404  fabricated from a first magnetic piece  406  that is separately illustrated in  FIGS. 25 and 26 , and a second magnetic piece  408 . 
         [0074]    Referring now to  FIGS. 25 and 26 , the first magnetic piece  406  generally includes a generally flat or planar base  110  and upstanding side walls  112 ,  114 , and  116  extending upwardly from the base  110 . The sidewalls  112 ,  114 ,  116  are generally straight and rectilinear on their exterior but are round on the interior to define a substantially semicircular interior recess or receptacle  118  above the base  110 . A round projection  120  extends upwardly from the base  110  in a central portion of the receptacle  118 . In the example shown, the periphery of the projection  120  is generally circular and completes a 360° arc on the base  110 , while the receptacle  118  is open sided and completes much less than a 360° arc above the base  110 . 
         [0075]    A front edge  122  of the base  110  is exposed and unlike the core piece  106  ( FIGS. 1 and 2 ) in the example core piece  206  as shown the groove  124  and the tapered side edge  126  are omitted. The front edge  122  of the base  110  in the core piece  106  is entirely straight and linear, and in the example shown may also be chamfered as shown to assist with seating of the bobbin  402  in a desired position and orientation. 
         [0076]    The core piece  406  may be fabricated from a known magnetic material according to known processes. The core piece  408  ( FIGS. 29-31 ) may be fabricated as essentially an identical piece to the core piece  406  in contemplated embodiments. 
         [0077]    Referring now to  FIGS. 27 and 28 , the bobbin  402  is fabricated from an electrically nonconductive or insulative material and generally includes an upper flange  440 , a tubular body  442 , a lower flange  444  and a connecting portion  446 . The flanges  440 ,  444  define a winding space  448  to accommodate a primary winding or coil and a secondary winding or coil according to known methods and techniques. The coils or windings are terminated or connected to one of a plurality of electrically conductive pins  450 ,  452 ,  454 ,  456  provided in the connecting portion  446 . The pins  450 ,  452 ,  454 ,  456  generally extend downwardly from the connecting portion  446  and generally parallel to a longitudinal axis (not shown in  FIG. 27  but similar to the axis  158  shown in  FIG. 4 ). 
         [0078]    One of the pins, namely the pin  450  in the example of  FIG. 27 , is a ground pin which, unlike the other pins includes an axial pin board portion  460  extending generally parallel to the axis of the other pins  452 ,  454 ,  456  for connection to a circuit board via a through-hole therein, and a component ground portion  462  extending generally perpendicular to the axis of the other pins  452 ,  454 ,  456 . In other words, the ground pin  450  includes a right angle bend with the ground portion  462  extending from one side of the right angle bend and the pin board portion  460  extending from the other side of the right angle bend. As such, the ground portion  462  in the example shown in  FIG. 27  extends parallel to a horizontal upper wall  464  of the connecting portion  446  and also parallel to a major surface of the bobbin lower flange  444 , while the pin board portion  460  extends perpendicularly from a bottom wall  466  of the connecting portion  446 . The right angle bend facilitates the connection of the ground pin  450  to the bobbin  402  as further explained below. 
         [0079]    The flanges  440 ,  444  each include a central opening  468  communicating with a hollow interior of the tubular portion  442 . The central opening  468  cooperates with the projections  120  of the magnetic core piece  406  ( FIGS. 25 and 26 ) when the bobbin  402  is assembled to the core piece  406 . 
         [0080]    As shown in  FIG. 29 , the ground portion  462  of the ground pin  450  generally lies alongside the major surface of the bobbin flange  440 , and may be adhered in position with conductive epoxy  470  to ensure electrical connection thereto. 
         [0081]    As shown in  FIG. 30 , the bobbin  402  may be assembled with the core piece  406 , and as shown in  FIG. 31 , the second core piece  408  is also assembled so that the bobbin  402  is sandwiched between the core pieces  406  and  408 , using the openings  468  ( FIGS. 27 and 28 ) in the bobbin  402  and the projections  120  ( FIGS. 25 and 26 ) in the core pieces  406  and  408  to guide the pieces into the proper orientation. The magnetic core pieces  406  and  408  may be gapped from one another when assembled to the bobbin  402  in any manner known in the art. 
         [0082]    In comparison to the first exemplary embodiment, the connection of the component ground portion  462  and the bobbin may be reliably accomplished in fewer manufacturing steps and at comparatively lower cost than has conventionally been provided, while providing a slightly simpler shape to the magnetic core piece  406 . 
         [0083]    In comparison to conventional transformer components having a wire connected to the magnetic core on one end and connected to an electrically quiet node at is opposite end, noticeable improvements in performance have been observed. Set forth below in Table 1 is a comparative example of Direct Current Resistance (DCR) of such conventional transformer components and the embodiments described above. In Table 1, Solution A refers to the embodiment of component  100 , Solution B refers to the embodiments of components  200  or  300 , and Solution C refers to the embodiment of component  400  described above. 
         [0000]    
       
         
               
               
               
             
               
               
               
               
               
             
           
               
                   
                 TABLE 1 
               
             
             
               
                   
                   
               
               
                   
                 DCR between core and grounding pin (kOhm) 
                   
               
             
          
           
               
                 Sample 
                 Traditional 
                 Solution 
                 Solution 
                 Solution 
               
               
                 # 
                 method 
                 A 
                 B 
                 C 
               
               
                   
               
               
                 1 
                 11.20 
                 4.69 
                 3.25 
                 2.78 
               
               
                 2 
                 14.50 
                 3.14 
                 2.26 
                 2.73 
               
               
                 3 
                 10.26 
                 3.75 
                 1.69 
                 2.58 
               
               
                 4 
                 11.98 
                 3.88 
                 2.42 
                 2.71 
               
               
                   
               
             
          
         
       
     
         [0084]      FIG. 32  is a comparative ground resistance chart of conventional transformer components and components fabricated in accordance with embodiments of the present invention. In  FIG. 32 , invention A refers to the embodiment of component  100 , invention B refers to the embodiments of components  200  or  300 , and invention C refers to the embodiment of component  400  described above. 
         [0085]    The benefits and advantages of the inventive concepts herein are now believed to be evident in view of the exemplary embodiments disclosed. 
         [0086]    An embodiment of a circuit board transformer component has been disclosed including: a bobbin provided with a plurality of electrically conductive pins; and at least one magnetic body assembled to the bobbin, wherein at least one of the electrically conductive pins is a ground pin comprising a board pin portion and a component ground section extending substantially perpendicular to the board pin portion. 
         [0087]    Optionally, the bobbin may include a connecting portion having a rear wall, and the component ground section of the ground pin may extend perpendicular to the rear wall. The magnetic body may include a first magnetic core piece, the first magnetic core piece comprising a front edge and a groove formed in the front edge. The component ground section of the ground pin may be received in the groove. A conductive epoxy securing the component ground section to the first magnetic core piece. 
         [0088]    Also optionally, the bobbin may include a connecting portion having an upper wall, and the component ground section of the ground pin may extend alongside the upper wall. The magnetic body may include a first magnetic core piece, and the first magnetic core piece may include a base and a side wall extending upwardly from the base. The component ground section may extend toward the side wall. A conductive epoxy may secure the component ground section to the side wall of the first core piece. 
         [0089]    The bobbin may optionally include a connecting portion having a side wall, and the component ground section of the ground pin may extend alongside the side wall. The magnetic body may include a first magnetic core piece, and the first magnetic core piece may include a front edge and a tapered section along a portion thereof. The component ground section may extend toward the tapered section. A side wall may extending from the tapered section, and a conductive epoxy may secure the component ground section to the side wall of the tapered section. 
         [0090]    Optionally, the bobbin may further include at least one flange, and the component ground section may extend parallel to the at least one flange. The component ground section may extend alongside the at least one flange. A conductive epoxy may secure the component ground section to the at least one flange. 
         [0091]    Optionally, the magnetic body may include a first magnetic piece and a second magnetic piece sandwiching the bobbin. The bobbin may include a first flange, a second flange and a winding space therebetween, and the connecting portion may extend adjacent one of the first and second flanges. The plurality of pins may extend from the connector portion in a row. The ground pin may be located on the end of the row, or the ground pin may be located adjacent at least two other pins in the row. The bobbin may also include a first flange, a second flange and a tubular portion extending therebetween. The tubular portion may define an axis, and the board pin portion may extend parallel to the axis. 
         [0092]    An embodiment of a circuit board transformer component is also disclosed. The transformer component includes: a bobbin defining a winding space and a connector portion provided with a plurality of electrically conductive pins; at least one magnetic body assembled to the bobbin, wherein at least one of the electrically conductive pins is a ground pin comprising a board pin portion and a component ground section extending substantially perpendicular to the board pin portion; and a conductive epoxy securing the component ground section to at least of the magnetic body and the bobbin. 
         [0093]    A method of manufacturing a circuit board transformer component is also disclosed. The method includes: providing a bobbin defining a winding space and a connector portion provided with a plurality of electrically conductive pins, at least one of the electrically conductive pins being a ground pin having a board pin portion and a component ground section extending substantially perpendicular to the board pin portion; assembling the bobbin with at least one magnetic body; and securing the component ground section to at least of the magnetic body and the bobbin with a conductive epoxy. 
         [0094]    This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.