Abstract:
A high voltage transformer employed in an inverter includes a first core and a second core. The second core is coupled to the first core. The second core is wrapped by at least one primary winding and at least one secondary winding of the transformer. The first core is made of manganese-zinc alloy, and the second core is made of nickel-zinc alloy, so as to achieve that conductive coefficient of the first core is much higher than conductive coefficient of the second core.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a divisional application of co-pending application Ser. No. 12/506,449, filed Jul. 21, 2009. 
     
    
     BACKGROUND 
       [0002]    1. Technical Field 
         [0003]    The present disclosure relates to a high voltage transformer for an inverter. 
         [0004]    2. Description of Related Art 
         [0005]    Normally, magnetic components, such as transformers, are used in electronic devices. For example, transformers used in inverters of liquid crystal displays (LCDs) convert received voltage signals into high voltage signals adapted for the LCDs. 
         [0006]    In order to avoid the requirement for secondary windings on the transformers to discharge to cores of the transformers, distance between either the bobbins and cores can be increased, or the cores can be fabricated of non-conductive material, such as a nickel-zinc alloy. However, in the first case, height of the transformers must be increased, impairing industry preferences for the LCDs to be light and small. In the second case, the specialized fabrication material increases costs. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  is a schematic diagram of a first embodiment of a high voltage transformer of the present disclosure. 
           [0008]      FIG. 2  is a schematic diagram of a second embodiment of a high voltage transformer of the present disclosure. 
           [0009]      FIG. 3  is a schematic diagram of a third embodiment of a high voltage transformer of the present disclosure. 
           [0010]      FIG. 4  is a schematic diagram of a fourth embodiment of a high voltage transformer of the present disclosure. 
           [0011]      FIG. 5  is a schematic diagram of a fifth embodiment of a high voltage transformer of the present disclosure. 
           [0012]      FIG. 6  is a schematic diagram of a sixth embodiment of a high voltage transformer of the present disclosure. 
           [0013]      FIG. 7  is a schematic diagram of a seventh embodiment of a high voltage transformer of the present disclosure. 
           [0014]      FIG. 8  is a schematic diagram of a eighth embodiment of a high voltage transformer of the present disclosure. 
           [0015]      FIG. 8A  is a side view of  FIG. 8 . 
           [0016]      FIG. 9  is a schematic diagram of a ninth embodiment of a high voltage transformer of the present disclosure. 
           [0017]      FIG. 10  is a schematic diagram of a tenth embodiment of a high voltage transformer of the present disclosure. 
           [0018]      FIG. 11  is a schematic diagram of a eleventh embodiment of a high voltage transformer of the present disclosure. 
           [0019]      FIG. 12  is a schematic diagram of a twelfth embodiment of a high voltage transformer of the present disclosure. 
           [0020]      FIG. 13  is a schematic diagram of a thirteenth embodiment of a high voltage transformer of the present disclosure. 
           [0021]      FIG. 14  is a schematic diagram of a fourteenth embodiment of a high voltage transformer of the present disclosure. 
           [0022]      FIG. 15  is a schematic diagram of a fifteenth embodiment of a high voltage transformer of the present disclosure. 
           [0023]      FIG. 16  is a schematic diagram of a sixteenth embodiment of a high voltage transformer of the present disclosure. 
           [0024]      FIG. 17  is a schematic diagram of a seventeenth embodiment of a high voltage transformer of the present disclosure. 
           [0025]      FIG. 18  is a schematic diagram of a eighteenth embodiment of a high voltage transformer of the present disclosure. 
           [0026]      FIG. 19  is a schematic diagram of a nineteenth embodiment of a high voltage transformer of the present disclosure. 
           [0027]      FIG. 20  is a schematic diagram of a twentieth embodiment of a high voltage transformer of the present disclosure. 
           [0028]      FIG. 20A  is a schematic diagram of a twenty-first embodiment of a high voltage transformer of the present disclosure. 
           [0029]      FIG. 20B  is a schematic diagram of a twenty-second embodiment of a high voltage transformer of the present disclosure. 
           [0030]      FIG. 21  is a schematic diagram of a twenty-third embodiment of a high voltage transformer of the present disclosure. 
           [0031]      FIG. 22  is a schematic diagram of a twenty-fourth embodiment of a high voltage transformer of the present disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0032]    In all embodiments of the disclosure, cores are accepted in bobbins (not shown) in transformers, and primary windings and secondary windings are applied on corresponding regions of the bobbins. For brevity, the bobbins are omitted, and the primary and secondary windings are described as applied to the cores directly. 
         [0033]      FIG. 1  is a schematic diagram of a first embodiment of a high voltage transformer  10 . The transformer  10  comprises a first core  11  and a second core  12  coupled to the first core  11 . In one embodiment, the first core  11  is an “M” type core and the second core  12  an “I” type core. One end of the second core  12  is wrapped by a primary winding P 1 , and the other end thereof is wrapped by a secondary winding S 1 . In other words, the cores  11 ,  12  of the high voltage transformer  10  form a “MI” type core assembly. As illustrated, conductive coefficient of the first core  11  is at least 100 times of that of the second core  12 . The first core  11  is made of manganese-zinc (MZ) alloy, and the second core  12  is made of nickel-zinc (NZ) alloy. 
         [0034]      FIG. 2  is a schematic diagram of second embodiment of a high voltage transformer  20 , differing from high voltage transformer  10  in that a first core  21  of the high voltage transformer  20  is a “C” type core, that is, the cores  21 ,  22  of the high voltage transformer  20  form a “CI” type core assembly. 
         [0035]      FIG. 3  is a schematic diagram of a third embodiment of a high voltage transformer  30 , differing from high voltage transformer  10  in that a first core  31  of the high voltage transformer  30  is a “         ” type core, that is, the cores  31 ,  32  of the high voltage transformer  20  form a “          I” type core assembly. 
         [0036]      FIG. 4  is a schematic diagram of a fourth embodiment of a high voltage transformer  40 . The high voltage transformer  40  comprises a first core  41  and a second core  42 , both of which are “E” type cores, arranged face to face to form a “         ” type core assembly. Similarly, conductive coefficient of the first core  41  is at least 100 times of that of the second core  42 . The first core  41  is made of manganese-zinc alloy, and the second core  42  is made of nickel-zinc alloy. The “         ” type core assembly comprises a first leg L 41 , a second leg L 42  and a third leg L 43 . The first leg L 41  and the third leg L 43  are wrapped by secondary windings S 41 , S 42 , respectively. The second leg L 42  is wrapped by a primary winding P 4 . In one embodiment, the first, second, and third legs L 41 , L 42 , L 43  are the same length. 
         [0037]      FIG. 5  is a schematic diagram of a fifth embodiment of a high voltage transformer  50 , differing from high voltage transformer  40  in that a first core  51  of the high voltage transformer  50  is a “C” type core, and a second core  52  is a “T” type core, that is, the cores  51 ,  52  of the high voltage transformer  50  form a “CT” type core assembly. 
         [0038]      FIG. 6  is a schematic diagram of a sixth embodiment of a high voltage transformer  50 ′, differing from high voltage transformer  50  in that legs L 51 ′, L 52 ′ L 53 ′ are different length. In detail, the first leg L 51 ′ and the second leg L 52 ′ are the same length, being shorter than third leg L 53 ′. 
         [0039]      FIG. 7  is a schematic diagram of a seventh embodiment of a high voltage transformer  60 . The high voltage transformer  60  comprises a first core  61  and a second core  62 , both of which are “U” type cores and arranged face to face. In one embodiment, the first core  61  is wrapped by primary windings P 61 , P 62 , and the second core  62  is wrapped by secondary windings S 61 , S 62 . Similarly, conductive coefficient of the first core  61  is at least 100 times of that of the second core  62 . The first core  61  is made of manganese-zinc alloy, and the second core  62  is made of nickel-zinc alloy. 
         [0040]      FIG. 8  is a schematic diagram of an eighth embodiment of a high voltage transformer  70 , differing from high voltage transformer  60  in that the high voltage transformer  70  comprises at least one “I” type core disposed on “U” type cores  71 ,  72  to form a “         ” type core assembly. In one embodiment, there is at least one air gap  74  (referring to  FIG. 8A ) between a plane of the “I” type core  73  and a plane of the “U” type cores  71 ,  72 , to adjust leakage inductance of the high voltage transformer  70 . 
         [0041]      FIG. 9  is a schematic diagram of a ninth embodiment of a high voltage transformer  70 ′, differing from high voltage transformer  70  in that high voltage transformer  70 ′ comprises two “I” type cores  74 ,  75  disposed between the “U” type cores  71 ′,  72 ′. Similarly, an air gap  76  between the two “I” type cores  74 ,  75  and the “U” type cores  71 ′,  72 ′, adjusts leakage inductance of the high voltage transformer  70 ′. 
         [0042]      FIG. 10  is a schematic diagram of a tenth embodiment of a high voltage transformer  80 , differing from high voltage transformer  60  of  FIG. 7  in that a first core  81  and a second core  82  of the high voltage transformer  80  form an “IC” type core assembly. 
         [0043]      FIG. 11  is a schematic diagram of an eleventh embodiment of a high voltage transformer  80 ′, differing from high voltage transformer  80  in that the high voltage transformer  80 ′ comprises a third core  83 . In one embodiment, the third core  83  is a “I” type core, disposed on the first and second cores  81 ′,  82 ′, which forms a “         ” type core assembly. 
         [0044]      FIG. 12  is a schematic diagram of a twelfth embodiment of a high voltage transformer  90 . The high voltage transformer  90  comprises a pair of “E” type cores  91 ,  92 . The cores  91 ,  92  are arranged face to face and form a “         ” type core assembly comprising a first leg L 91 , a second leg L 92 , and a third leg L 93 . As illustrated, the second leg L 92  is wrapped by a primary winding P 9  and a secondary winding S 9 . In detail, the primary winding P 9  is wrapped on the “E” type core  92  of the second leg L 92 , and the secondary winding S 9  is wrapped on the “E” type core  91  of the second leg L 92 . Similarly, conductive coefficient of the core  91  is at least 100 times of that of the core  92 . The core  61  is made of a manganese-zinc alloy, and the core  62  is made of a nickel-zinc alloy. 
         [0045]      FIG. 13  is a schematic diagram of a thirteenth embodiment of a high voltage transformer  90 ′, differing from high voltage transformer  90  in that a secondary winding S 9 ′ is wrapped on both the cores  91 ′,  92 ′ of the second leg L 92 ′. In detail, a high voltage portion of the secondary winding S 9 ′ and a primary winding P 9 ′ are wrapped on the core  92 ′, and a low voltage portion of the secondary winding S 9 ′ is wrapped on the core  91 ′. 
         [0046]      FIG. 14  is a schematic diagram of a fourteenth embodiment of a high voltage transformer  100 . The high voltage transformer  100  comprises an “I” type core  101  and at least two “C” type cores  102 ,  103 . As illustrated, the “I” type core  101  is wrapped by a secondary winding S 10 , and the two “C” type cores  102 ,  103  are wrapped by a primary winding P 10 . The cores  101 ,  102 , and  103  form a “         ” type core assembly. Similarly, conductive coefficient of the core  101  is at least 100 times of that of the cores  102 ,  103 . The core  101  is made of a manganese-zinc alloy, and the cores  102 ,  103  are made of a nickel-zinc alloy. The “         ” type core assembly comprises a first leg L 101 , a second leg L 102  and a third leg L 103 . The second leg L 102  is the “I” type core wrapped by the secondary winding S 10 , and the first leg L 101  is wrapped by the primary winding P 10 . The legs L 101 , L 102 , L 103  are the same length. 
         [0047]      FIG. 15  is a schematic diagram of a fifteenth embodiment of a high voltage transformer  200 , differing from high voltage transformer  100  in that the cores  112 ,  113  of the high voltage transformer  200  form an “CI” type core assembly. 
         [0048]      FIG. 16  is a schematic diagram of a sixteenth embodiment of a high voltage transformer  200 ′, differing from high voltage transformer  200  in that a first leg L 111 ′ and a second leg L 112 ′ are the same length, both being shorter than a third leg L 113 ′. 
         [0049]      FIG. 17  is a schematic diagram of a seventeenth embodiment of a high voltage transformer  300 , differing from high voltage transformer  100  in that the cores  122 ,  123  of the high voltage transformer  300  form a “FF” core assembly. A third leg L 123  is the “I” type core wrapped by a secondary winding S 21 , and a first leg L 121  is wrapped by a primary winding P 21 . 
         [0050]      FIG. 18  is a schematic diagram of an eighteenth embodiment of a high voltage transformer  300 ′, differing from high voltage transformer  90  in that the legs L 121 ′, L 122 ′, L 123 ′ are different lengths. In detail, first leg L 121 ′ and the second leg L 122 ′ are the same length, both being shorter than the third leg L 123 ′. 
         [0051]      FIG. 19  is a schematic diagram of a nineteenth embodiment of a high voltage transformer  400 , differing from high voltage transformer  100  in that the cores  132 ,  133 ,  134  form a “TTI” type core assembly. A first leg L 131  and a third leg L 133  are the Page of same length, both being longer than a second leg L 132 . 
         [0052]      FIG. 20  is a schematic diagram of a twentieth embodiment of a high voltage transformer  500 , differing from high voltage transformer  20  of  FIG. 2  in that the “I” type core  22  wraps a primary winding P 41  and at least two secondary windings S 411 , S 412 . In one embodiment, the primary winding P 41  is wrapped on the middle of the second core  142 , and the at least two secondary windings S 411 , S 412  are wrapped on the both sides of the primary winding P 41 . Similarly, conductive coefficient of the core  141  is at least 100 times of that of the core  142 . The core  141  is made of a manganese-zinc alloy, and the core  142  is made of a nickel-zinc alloy. 
         [0053]      FIG. 20A  is a schematic diagram of a twenty-first embodiment of a high voltage transformer  500 ′, differing from high voltage transformer  500  in that the first core  141 ′ is a “E” type core and the primary winding P 41  comprises a first sub primary winding P 411  and a second sub primary winding P 412 . In one embodiment, each the first and the second sub primary winding P 411 , P 412  has a first input and a second input. The first sub primary winding P 411  is connected to the second sub primary winding P 412  in series. In detail, the first input of the first sub primary winding P 411  is connected to the second input of the second sub primary winding P 412 , and the second input of the first sub primary winding P 411  is connected to the first input of the second sub primary winding P 412 . Therefore, direction of flux generated by the first sub primary winding P 411  and the second sub primary winding P 412  are opposite. In one embodiment, the first core  141  and the second core  142  form a “         ” type core assembly. 
         [0054]      FIG. 20B  is a schematic diagram of a twenty-second embodiment of a high voltage transformer  500 ′, differing from high voltage transformer  500 ′ of  FIG. 20A  in that the first sub primary winding P 411  is connected to the second sub primary winding P 412  in parallel. In detail, the first inputs of the first and second sub primary windings P 411  and P 412  are connected together, and the second input of the first and second sub primary windings P 411  and P 412  are connected together. 
         [0055]      FIG. 21  is a schematic diagram of a twenty-third embodiment of a high voltage transformer  600 , differing from high voltage transformer  500  in that the high voltage transformer  600  comprises at least two independent primary windings P 411 ′, P 412 ′ and at least two secondary windings S 411 ′, S 412 ′. The secondary windings S 411 ′, S 412 ′ are wrapped on the middle of the second core  142 , and the primary windings P 411 ′, P 412 ′ are wrapped on both sides of the second core  142 . Alternatively, the two primary windings P 411 ′, P 412 ′ can be integrated into one primary winding, connected in series or parallel. 
         [0056]      FIG. 22  is a schematic diagram of a twenty-fourth embodiment of a high voltage transformer  700 , differing from high voltage transformer  700  in that two protruding portions  153  are disposed on the first core  153  in the high voltage transformer  700 . As illustrated, the first core  151  is divided into three portions by the two protruding portions  153 . The cores  151 ,  152  form a “         ” type core assembly that comprises three wrapping regions corresponding to the three portions of the first core  151 . A primary winding P 51  is wrapped on a middle wrapping region of the “         ” type core assembly, and the secondary windings S 511 , S 512  are wrapped on both sides wrapping region of the “         ” type core assembly. 
         [0057]    In high voltage transformers of the disclosure, cores for wrapping secondary windings are made of a nickel-zinc alloy, and other portions of the cores are made of a manganese-zinc alloy, lowering costs and meeting small size and weight requirements of electronic devices. 
         [0058]    Although the features and elements of the present disclosure are described in various inventive embodiment in particular combinations, each feature or element can be configured alone or in various within the principles of the present disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.