Patent Publication Number: US-2015070122-A1

Title: Three Piece Transformer Core

Description:
FIELD OF THE INVENTION 
     The present invention is in the field of transformers. 
     DISCUSSION OF RELATED ART 
     Transformers are electronic parts that are found in a variety of different electronic products such as televisions and computers. Transformers are also used in power supplies for changing the type of electricity that electronic products might use. Transformers have a variety of different constructions but all have a core with a winding around the core. The core can have a variety of different configurations. Typical transformer cores have a pair of symmetrical sections made of two symmetrical pieces. 
     Transformer cores transfer energy by inductive coupling between winding circuits. A primary winding and a secondary winding can be wound on a bobbin. Transformers have been used for changing voltage and amperage of electricity for over a hundred years. The patent literature describes a variety of different transformers, such as U.S. Pat. No. 652,027 issued Jun. 19, 1900 to Johannesen. The Johannesen reference describes having core windings around a core, the disclosure of which is incorporated herein by reference. Other transformers are entirely tubular shaped, such as described in Depp U.S. Pat. No. 721,289 entitled Transformer, issued Feb. 24, 1903, the disclosure of which is incorporated herein by reference. 
     SUMMARY OF THE INVENTION 
     A three piece transformer core includes a top having a pair of top lateral faces, namely a top left lateral face and a top right lateral face. The top left lateral face has a lower edge bounded at a top lower left face. The top right lateral face has a lower edge bounded at a top lower right face. A core left side section has a core left side section first leg and a core left side section second leg. 
     The core left side section has a left lateral upper face configured to abut the top lower left face of the top. A core right side section has a core right side section first leg and a core right side section second leg. The core right side section has a right lateral upper face configured to abut the top lower right face of the top. The core right side section first leg has a right first leg side joining face to abut to a left first leg side joining face of the core left side section first leg. The core right side section second leg has a right second leg side joining face to abut a left second leg side joining face of the core left side section second leg. A bobbin receives the three piece transformer core, and the bobbin further includes electrical contacts formed as legs. 
     The three piece transformer core optionally also includes a recess formed in a lower surface of the top. The top left lateral face is preferably orthogonal to the top lower left face. The top right lateral face is orthogonal to the top lower right face, wherein the top lower left face is bounded between the top left lateral face and the recess, and wherein the top lower right face is bounded between the top right lateral face and the recess. The core left side section has a left center face formed on a left center post. The core right side section has a right center face formed on a right center post. The left center face does not touch the right center face when the three piece transformer core is assembled. The left center face is located between the left first leg side joining face and the left second leg side joining face. The right center face is located between the right first leg side joining face and the right second leg side joining face. A left first leg upper face formed on core left side section first leg is configured to have flush contact with a left portion of the top lower rear face. A left second leg upper face formed on the core left side section second leg is configured to have flush contact with a left portion of the top lower front face. A right first leg upper face formed on core right side section first leg is configured to have flush contact with a right portion of the top lower rear face. A right second leg upper face formed on the core right side section second leg is configured to have flush contact with a right portion of the top lower front face. The right first leg side joining face, the right second leg side joining face, left first leg side joining face, and left second leg side joining face are preferably rectangular having vertical orientation where the height of the rectangular cross-section is greater than the width of the rectangular cross-section. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a lower perspective exploded view diagram of the present invention. 
         FIG. 2  is an upper perspective exploded view diagram of the present invention. 
         FIG. 3  is an assembled perspective view of the present invention. 
     
    
    
     The following call out list of elements can be a useful guide in referencing the element numbers of the drawings.
       10  Transformer     20  Core     21  Center Post     22  Leg     23  Side     24  Top     25  Recess     26  Core Top Section     27  Core Left Side Section     28  Core Right Side Section     30  Bobbin     40  Pins     51  Center Face     52  Leg Face     53  Recess Face Vertical Cross-Section     54  Top Lateral Face     55  Top Front Face     56  Top Lower Right Face     57  Top Lower Left Face     58  Top Lower Rear Face     59  Top Lower Front Face     61  Left Lateral Upper Face     62  Left First Leg Upper Face     63  Left Second Leg Upper Face     64  Right First Leg Upper Face     65  Right Lateral Upper Face     66  Right Second Leg Upper Face     67  Left Lateral Side Face     68  Right First Leg Side Joining Face     69  Right Second Leg Side Joining Face     71  Left Lateral Bottom Face     72  Left First Leg Bottom Face     73  Left Second Leg Bottom Face     74  Right First Leg Bottom Face     75  Right Lateral Bottom Face     76  Right Second Leg Bottom Face     77  Right Lateral Side Face     78  Left First Leg Side Joining Face     79  Left Second Leg Side Joining Face   

     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The present invention transformer  10  has a three-piece core  20 . The core  20  has a top  24  that connects to a pair of sides  23 , namely a core left section  27  and a core right section  28 . Each of the sides  23  have a center post  21  that extends from a lateral portion of the side  23 . The top  24  aligns to each of the sides  23 . The top  24  has a recess face vertical cross-section  53  that defines a periphery of a recess  25  formed on a lower surface of the top  24 . The sides have a pair of legs  22  such that there are a total of four legs  22 . The core left section  27  has a pair of legs and the core right section  28  also has a pair of legs. The core  25  is formed to fit around a bobbin  30 . Pins  40  extend from the bobbin  30 . The bobbin  30  and pins  40  can be made according to that shown in the extensive prior art. The core left section and core right section are both shaped with a center face  51  disposed on an inside surface of the center  21 . A center face  51  can be circular to match a circular cross-section of the center post. The core left section and core right section additionally have a face of the leg also called the leg face  52 . 
     The core left side section can also be on the right side if a viewer inverts the viewing angle or turns the core upside down. The core left side section can also be on the right side if a viewer inverts the viewing angle or turns the core upside down. The terminology describing the core of the left side section and the core right side section refers to the pair of cores, namely the first core side section and the second core side section as shown in the figures. Similarly, the top and bottom surfaces are describing the orientation of surfaces as shown in the figures. A top surface could be placed on a bottom if the core were mounted upside down. Similarly, a bottom surface could be on the top if the core were mounted upside down. The terminology describing the top or bottom is describing the orientation of surfaces shown in the figures. 
     The top  24  has a top lateral face  54  at a left and right lateral side of the top  24 . The top has a pair of lateral faces  54  that are parallel to each other and oppose each other. The top also has a top front face  55  which is parallel to and opposite orientation of a top rear face. The top  24  is also shaped so that it has a top lower right face  56 , top lower left face  57 , top lower rear face  58 , and top lower front face  59  forming four areas of the recess face vertical cross-section  53 . The top lower right face  56  faces downward and the top lower left face  57  also faces downward. The top lower rear face  58  and top lower front face  59  connect the top lower right face  56  to the top lower left face  57 . The four areas of the recess face vertical cross-section  53  are preferably parallel to each other. The four areas of the recess face vertical cross-section  53  can form a rectangular or square profile around a recess. The recess face vertical cross-section  53  makes a joining with faces of the side pieces. Generally speaking, the faces are either orthogonal or parallel to each other. 
     The core left section has various faces including a left lateral upper face  61 , a left first leg upper face  62  and a left second leg upper face  63 . The left lateral upper face  61  connects to the top lower left face  57  of the top. The left first leg upper face  62  connects to a left half of the top lower rear face  58 . Similarly, the left second leg upper face  63  connects to a left half of the top lower front face  59 . Preferably, the connection between the top and the side are with a flush exterior surface so that the core could be wrapped in an insulated protective tape during final construction. Making connection means that the members are in contact on a surface or touching on a surface such that the core has generally continuous inductive capability. 
     The core right section has various faces including a right first leg upper face  64 , a right lateral upper face  65  and a right second leg upper face  66 . The right first leg upper face  64  is formed on the right leg upper surface so that it makes connection to the right half of the top lower rear face  58 . Similarly, the right lateral upper face  65  is configured so that it makes connection with the top lower right face  56 . Also, the right second leg upper face  66  makes connection with the right side of the top lower front face  59 . The connection being made is preferably one that provides magnetic continuity such that there is no substantial gap between the members. 
     The core right section and core left section both have a first leg and a second leg. This means that the core right section has a core right section first leg and a core right section second leg. The core left section has a core left section first leg and a core left section second leg. The first leg and the second leg are preferably box shaped having rectangularity and cubic shape. The legs preferably have a top surface that is coplanar to the lateral face that is between the top surface of the legs. The top surface of the first leg is preferably coplanar to the top surface of the second leg. Furthermore, the top surface of the right first leg is preferably coplanar to the top surface of the left first leg. Similarly, the top surface of the right second leg is preferably coplanar to the top surface of the left second leg. Also, the top surface of the lateral portion of the right section called the right lateral upper face  65  is preferably coplanar to the top surface of the lateral portion of the left section called the left lateral upper face  61 . Preferably, the left lateral upper face  61 , the left first leg upper face  62 , the left second leg upper face  63 , the right first leg upper face  64 , the right lateral upper face  65  and the right second leg upper face  66  are all coplanar and match the profile of the recess face vertical cross-section  53 . The top fits on the left and right side sections like a rectangular lid. 
     The left and right side sections of the core are also joined to each other. The leg faces  52  of each of the left and right side sections are joined to each other meaning that they are touching but not necessarily glued together, although they could be such as by using epoxy or cyanoacrylate. The right first leg side joining face  68  joins to the left first side joining face  78 . The right second leg side joining face  69  joins to the left second leg side joining face  79 . The leg faces  52  are vertically oriented such that they define a vertically oriented rectangle. 
     The center face  51  of the left and right sides preferably do not touch each other, but rather have a gap between the surfaces. The bobbin has a circular aperture for receiving the center  21 . The leg faces  52  can be molded to be coplanar with the center face  51  when the left and right side sections are originally cast. Subsequently, the center face  51  can be abrasion material removed or cut to a surface that is not coplanar to the leg faces  52 . 
     The left and right side sections of the core having a generally cubical shape may have lateral side faces. For example, the left side may have a left lateral side face  67  and the right side may have a right lateral side face  77 . The left side section of the core may further include a left side section bottom face that includes a left lateral bottom face  71 , a left first leg bottom face  72 , and a left second leg bottom face  73  formed on the left side section. The right side section may have a right side section bottom face that includes a right first leg bottom face  74 , a right lateral bottom face  75  and a right second leg bottom face  76 . Right side section bottom face and the left side section bottom face are preferably coplanar so that the pair of bottom faces come together to form a rectangular frame around the bobbin. The left second leg bottom face  73  preferably continues to the right second leg bottom face  76 . The first left leg bottom face  72  preferably continues to the right first leg bottom face  74 . 
     The right lateral bottom face  75  is orthogonal to the right lateral side face  77 . The right lateral side face  77  is orthogonal to the right lateral upper face  65 . The right lateral side face  77  is bounded at an upper edge by the right lateral upper face  65 , and a right lateral side face  77  is bounded at a lower edge by the right lateral bottom face  75 . The right lateral upper face  65  is parallel to the right lateral bottom face  75 . The right lateral side face  77  is parallel to the left lateral side face  67 . The left lateral side face  67  is orthogonal to the left lateral bottom face  71 . The left lateral side face  67  is also orthogonal to the left lateral upper face  61 . The left lateral side face  67  is bounded at an upper edge by the left lateral upper face  61 , and the left lateral is bounded at a lower edge by the left lateral bottom face  71 . 
     Each of the legs have an outside surface and an inside surface. The leg outside surface and the leg inside surface are both orthogonal to the leg side joining face. For example, a right first leg side joining face  68  is orthogonal to the right first leg outside surface and to the right first leg inside surface. The right first leg side joining face  68  is bounded between the right first leg outside surface and the right first leg inside surface. The right second leg side joining face  69  is orthogonal to the right second leg outside surface and to the right second leg inside surface. The right second leg side joining face  69  is bounded between the right second leg outside surface and the right second leg inside surface. The left first leg side joining face  78  is orthogonal to the left first leg inside surface and to the left first leg outside surface. The left first leg side joining face  78  is bounded between the left first leg inside surface and the left first leg outside surface. Each leg side joining face is bounded at its left and right edges by the leg outside surface and the leg inside surface. 
     Each leg side joining face is also bounded at its top and bottom edges by the leg upper face and the leg bottom face. The left first leg side joining face  78  is orthogonal to the left first leg upper face  62  and the left first leg bottom face  72 . The left first leg side joining face  78  is bounded between the left first leg upper face  62  and the left first leg bottom face  72 . The left second leg side joining face  78  is also orthogonal to the left second leg bottom face  73  and the left second leg upper face  63 . The left second leg side joining face  78  is bounded between the left second leg bottom face  73  and the left second leg upper face  63 . The right first leg side joining face  68  is orthogonal to the right first leg upper face  64  and the right first leg bottom face  74 . The right first leg side joining face  68  is also bounded between the right first leg upper face  64  and the right first leg bottom face  74 . The right second leg side joining face  69  is orthogonal to the right second leg upper face  66  and the right second leg bottom face  76 . The right second leg side joining face  69  is bounded between the right second leg upper face  66  and the right second leg bottom face  76 . 
     The center post preferably is of a circular cross-section while the legs are of rectangular cross-section. The following claims define the scope of the invention.