The present invention relates to transformers for use in inverters or the like that drive a luminaire like cold cathode type fluorescent lamp (CCFL) or external electrode fluorescent lamp (EEFL) or EL plate (electroluminescence plate) and the like,
Heretofore, as shown in the official gazette of JAPAN PATENT KOKAI KOHO H 10-70031 or
Furthermore, as shown in JAPAN PATENT KOKAI 2005-39050 or
In the conventional transformers of a type wherein the square ring type core or E-E type cores are used, and because of coupling of parallel portions 2b, 10a of the core mounted with windings in plane direction by means of right angle portions 2a, 12b, the entire unit becomes a large size in width direction, namely, in horizontal and plane direction relative to the substrate, and an occupied area of the transformer on the substrate in its plane direction becomes a large size which are the problems.
An object of the present invention is to provide a transformer of multi-output type suitable for its miniaturization. Furtheremore, another object of the present invention is to provide a transformer of one input multi-output type suitable for driving a plurality of the luminaire with an electric circuit that constitutes a single closed loop.
The present invention is constructed in such a way that at least two pieces of I type cores disposed at predetermined interval in parallel and C type cores disposed on the parallel plane of the I type cores at predetermined interval by being superimposed relative to the parallel plane and convex portions of both ends are coupled with both end portions of the I type cores are provided, and the primary windings are mounted on the I type cores by means of the bobbins respectively and the secondary windings are mounted at both sides of the primary windings. By this construction, the secondary side of the transformer is at least made as the 4 winding outputs. Furthermore, the secondary winding can be constructed with a plurality of electric wires which are arranged in parallel. In this case, the secondary side of the transformer may be made as at least 8 windings outputs.
Furthermore, the present invention is constructed in that a terminal mounting portion is provided in a high-voltage terminal disposing region of the bobbin, and the first terminal connected to one terminal of the secondary winding is mounted at the terminal mounting portion in the high-voltage terminal disposing region, and the second terminal connected to the other terminal of the secondary winding mounted on the bobbin is mounted in the low-voltage terminal disposing region in the rear part at a predetermined distance relative to the high-voltage terminal disposing region, and the second terminal is made as the ground terminal.
Still furthermore, the primary winding is mounted in the center of the each bobbin, and both the sides of the primary winding are mounted on the secondary winding, and the terminal mounting portion in the low-voltage disposing region is provided at both the sides of the primary winding.
Furthermore, the present invention is constructed in that the winding direction of the portion of the primary winding adjacent to the secondary winding is made identical with the winding direction of the secondary winding.
Furthermore, the present invention is constructed in that a winding end terminal side of the secondary winding closer to the primary winding is connected to the ground terminal, and as a result, high potential difference seldom occurs in the border of the primary winding and the secondary winding.
Furthermore, the present invention is constructed in that each terminal mounting portion is provided at the rear of each of the secondary windings, and a secondary ground terminal is provided at the terminal mounting portion, and a winding end of the secondary winding is connected to the secondary ground terminal.
Furthermore, this invention is constructed in that the high-voltage secondary terminal of the terminal mounting portion provided at one side of the I type core is connected to a connector having a pair of terminals for lamp connection and the high-voltage secondary terminal of the terminal mounting portion of the other side of the I type core is connected to another connector having a pair of terminals for lamp connection.
The present invention is constructed as set forth in the foregoing, whereby the primary winding and the secondary winding are tightly connected to provide a transformer of high efficiency suitable for a plurality of outputs and miniaturization. Furthermore, the present invention is capable of providing a transformer suitable for driving a large number of luminaire on an electronic circuit consisting of a single closed loop.
The construction of the present invention will be described in detail in the following by referring to the attached drawings.
One end convex surface 44a of the C type core 44 abuts and is fixed to one of two pieces of T type cores by means of a cutout portion 46 formed on the terminal mounting portions 30, 26 and also, abuts across the each core to be connected. The other end convex surface 44b of the C type core 44 abuts and is fixed to each of two pieces of the T type cores 40, 42 by means of the notched portions 48 formed on the terminal mounting portions 28, 24 and abuts and is fixed to 2 pieces of the I type cores 40, 42 by crossing each other portions.
Secondary winding 50 is wound between the terminal mounting portions 24 and 32 of the bobbin 20, and the secondary winding 52 is wound between the terminal mounting portions 34 and 26, and the primary winding 54 is wound between the terminal mounting portions 32 and 34. Furthermore, the secondary winding 56 is wound between the terminal mounting portions 28 and 36 of the bobbin 22, and the secondary winding 58 is wound between the terminal mounting portions 38 and 30, and the primary winding 60 is wound between the terminal mounting portions 36 and 38. In the drawings, the arrow marks attached to each of the windings indicate the winding directions based on the winding start end of the winding.
Between the terminal mounting portions 24 and 32 of each of the bobbins 20 and 22, and also between the terminal mounting portions 28 and 36 and also between the terminal mounting portions 38 and 30, a plurality of sheets of partitions 62 for insulation are respectively provided. The winding start ends 50a, 52a, 56a, 58a of the secondary windings 50, 52, 56, 58 are connected to the secondary side terminals 64, 66, 68, 70 by means of the grooves of the terminal mounting portions, and the winding terminate ends are connected to the secondary side terminals 72, 74, 76, 78 by means of the lead wires 50b, 52b, 56b, 58b.
Both terminals of the primary winding 54 are connected to the primary side terminals 80, 82, and both terminals of the primary winding 60 are connected to the primary side terminals 84, 86. The primary side terminals 86, 80 are connected in series by means of the lead wires, whereby the primary side terminals 84, 82 constitute an input terminal. For reference, primary side terminals 84, 80 are connected by means of the lead wires, and the primary side terminals 82, 86 are connected by means of the lead wires, whereby the primary windings 54, 60 may be connected in parallel.
In the foregoing construction, the transformer is mounted on the printed circuit board, and the primary side input terminals 82, 84 of the transformer are connected to the output side of the AC signals of the inverter circuit.
Lamps L1, L2 such as cold cathode type fluorescent lamps that are serially connected are connected between the terminals 64, 66 at the primary side by means of the connector (no illustration) and the lamps L3, L4 such as cold cathode type fluorescent lamps are connected between the terminals 68, 70 at the primary side by means of the connectors, The end portion of the side loser to the primary windings 54, 60 of the secondary windings 50, 52, 56, 58 are earthed through the secondary side terminals 72, 74 and 76, 78. The secondary side terminals 72, 74 and 76, 78 constitute the ground terminals and the ground terminals are earthed by means of a high-resistant element.
When the AC signals are inputted to the primary windings 54, 60, magnetic circuits are formed in the two pieces of the I type cores 40, 42, and the high-voltage AC output voltage is generated in the secondary windings 50, 52, 56 and 58. The direction of the magnetic flux formed in the I type cores 40, 42 are identical. The winding direction of the secondary windings 50, 52 are set in counter direction as shown in the drawing with the arrow direction, and the terminals 64, 66 are mutually of counter phases.
Similarly, the high-voltage secondary side terminals 68, 70 are mutually of counter phase. Accordingly, when the terminals 64, 68 are plus charge, the terminals 66, 70 become minus charge.
The secondary side terminals 72, 74, 76, 78 are earthed by means of the lead wires, whereby the secondary side ground terminals are formed. Numerals 88, 90 denote connectors mounted on the printed circuit board (illustration is omitted), and the lamp (illustration is omitted) mounted on the circuit board (illustration is omitted) is connected to the connector as shown in
In the foregoing construction, the transformer is divided into a high voltage terminal disposed regions 100, 102 opposed to the connectors 88, 90 in a shortest distance, and low voltage terminal disposed regions 104 positioned in the rear of the high voltage terminal disposed regions 100, 102 relative to the connectors 88, 90. With this arrangement, there is not a chance for the low voltage secondary side terminals 72, 74, 76, 78 entering into the high-voltage regions 100, 102, and the insulation distance between the secondary side terminals 64 and 72, and between the secondary side terminals 68 and 76, and between the secondary side terminals 66 and 74 and between the secondary side terminals 70 and 78, and thus, the discharge and the like can be prevented between them, and thus, the transformer can be safely operated.
For reference, a coupling structure of the I type core and the C type core may be formed as shown in
Another embodiment of the present invention will be described in the following by referring to
The part 54a of the primary winding 54 is wound in right-turn direction as shown with the arrow mark based on the winding start end (S) in
The secondary winding 56 is connected to the high-voltage secondary side terminal 68 disposed at the end portion of the outside of the terminal mounting portion 28, and the winding terminate end 56b is returned to the terminal mounting portion 28 along the periphery of the secondary winding 56, and is connected to the secondary ground terminal 76 disposed at the inside of the terminal mounting portion 28. The secondary winding 58 is connected to the high-voltage secondary side terminal 70 wherein the winding start end 58a is disposed at the end portion of the outside of the terminal mounting portion 30, and the winding terminate end 58b is returned to the terminal mounting portion 30 along the periphery of the secondary winding 58, and is connected to the secondary ground terminal 78 disposed at the inside of the terminal mounting portion 30. The primary side terminal 80 and the primary side terminal 86 are connected in series by means of the lead wire 81. The primary side terminals 84 and 82 constitute the primary input portion.
The secondary windings 50, 56 on the bobbins 20, 22 are wound in the right-turn direction with the winding start ends 50a, 56a respectively as the base in
The portion 54a adjacent to the secondary windings 50, 56 of the primary winding 54 becomes the right-turn direction identical with the secondary windings 50, 56 with the winding start end as the base, and the portion 54b adjacent to the secondary windings 52, 58 becomes the left-turn direction identical with the secondary windings 52, 58. As explained in the foregoing, when the winding directions of the winding adjacent to the primary winding and the secondary winding are arranged to be identical, the colliding of the magnetism, namely, the interference of the line of the magnetic force can be eliminated. Other constructions of the present embodiment are identical with the constructions of the embodiment shown in
In the foregoing construction, the transformer T is mounted on the printed circuit board, and the side of the AC signal output of the inverter circuit is connected to the primary side terminals 84, 82 of the transformer T, and this AC signal is inputted between the primary side-terminals 84, 82.
On the printed circuit board, the connectors CN1, CN2 for lamp connection are fixed and disposed in correspondence to the transformer T. Among a pair of the terminals A and B of the connector CN1, the high-voltage secondary side terminal 64 is connected to the one terminal A by means of the ballast capacitor, and the high-voltage secondary side terminal 68 is connected to the other terminal B by means of the ballast capacitor.
Furthermore, among a pair of the terminals of the connector CN2, the high-voltage secondary side terminal 70 is connected to the one terminal C by means of the ballast capacitor, and the high-voltage secondary side terminal 66 is connected to the other terminal D by means of the ballast capacitor. The secondary side ground terminals 72, 74 are connected in series by means of the lead wires, and similarly, the secondary side ground terminals 76, 78 are connected in series by means of the lead wire, and these lead wires are respectively earthed by means of the high resistance element such as the resistors R1, R2 (refer to
In the foregoing construction, on the printed circuit board, one or a plurality of 1 input 4 winding output transformer are disposed, and as a result, it becomes possible to drive the lamps arranged relative to the terminals of the connectors corresponding to each of the transformers efficiently with an electronic circuit consisting of one piece of closed loop. With respect to the embodiment mode for driving 16 lamps such as the cold cathode type fluorescent lamps and the like, the description is provided in the following by referring to
4 pieces of the transformers T are arranged in a row on the printed circuit board 12, and a pair of the connectors CN1, CN2 is arranged in a row corresponding to each of the transformers T. A pair of the connectors CN1, CN2 corresponding to each of the transformers T are connected as shown in
In
The electronic circuit of the lamps L1-L16 which are connected in the foregoing manner constitutes one closed loop, for example, assuming the electrode S of the lamp L1 as the starting point, the electrode S, lamp L15, connector CN2, windings 58, 56 of the transformer T, connector CN1, lamp L14, lamp L11, connector CN2, windings 58, 56 of the transformer T, connector CN1, lamp L10, lamp L7, connector CN2, windings 58, 56 of the transformer T, connector CN1, lamp L6, Lamp L3, connector CN2, windings 58, 56 of the transformer T, connector CN1, lamp L2, lamp L16, connector CN2, windings 52, 50 of the transformer T, connector CN1, lamp L13, lamp L12, connector CN2, windings 52, 50 of the transformer T, connector CN1, lamp L9, lamp L8, connector CN2, windings 52, 50 of the transformer T, connector CN1, lamp L5, lamp L4, connector CN2, windings 52, 50 of the transformer T, connector CN1 and the electrode E of the lamp L1 to return to the starting point S.
As shown in the foregoing, it becomes possible to light up the whole lamps with a uniform brightness by forming the electronic circuit of the lamps in one piece of the closed loop.
In the connection construction of the lamps, the voltage of the counter phase of the transformer T is applied to each of both terminals of a pair of the lamps L1, L15, L2, L16, L3, L6, L4, L5, L7, L10, L8, L9 which are connected in series, and each pair of the lamps is lighted up with the high voltage.
Furthermore, in
The secondary side ground terminals 72, 74 are connected in series by means of the lead wires, and the lead wires are earthed through the high resistance element. Also, the secondary ground terminals 76, 78 are connected in series by means of the lead wires, and the lead wires are earthed by means of the high-resistance element. The CN1, CN2 are connectors mounted on the printed circuit board (illustration is omitted), and the lamps (illustration is omitted) installed on the board is connected to the connector as shown in
In the foregoing construction, the transformer is divided to the high voltage terminal disposed regions 100, 102 opposed to the connectors CN1 and CN2 at the shortest distance, and to the low-voltage terminal disposed region 104 positioned at the rearward of the high-voltage terminal disposed regions 100, 102 relative to the connectors CN1, CN2. By this arrangement, there is no chance of the low-voltage secondary ground terminals 72, 74, 76, 78 into the high-voltage regions 100, 102, and the insulation distance between secondary side terminal 64 and the secondary ground terminal 72, and between the secondary side terminal 68 and the secondary ground terminal 76 and between the secondary side terminal 66 and the secondary ground terminal 74 and between the secondary side terminal 70 and the secondary ground terminal 78 become larger, and thus the discharge or the like between them can be prevented, and thus, the transformers can be operated safely.
The secondary winding 50 is wound in the right-turn as shown by the arrow mark in the drawing on the basis of the winding start end 50a as the standard, and the secondary winding 56 opposed to the winding in parallel is wound in the left turn on the basis of the winding start end 56a as the standard, and the secondary windings 50, 56 are opposite in the winding directions mutually. Also, the secondary windings 52, 58 are similar, and the secondary winding 52 being the left-turn, and the secondary winding 58 being the right-turn, and the winding directions of both the windings are counter directions.
Furthermore, the primary windings 54, 60 are similar such that the primary winding 54 is of the right-turn with the winding start end as the standard, and the primary winding 60 is the left-turn and both the windings are mutually of counter-direction. As described above, when the winding directions of the windings which are opposed and in parallel are reversed, the oscillation by the magnetic force of the windings can be cancelled out, preventing the heat generation of the windings. The primary windings 54, 60 are connected in parallel or in series. The outputs of the secondary high-voltage terminals 64, 68 are mutually in identical phase, and the secondary high-voltage terminals 66, 70 become the counter phase to the secondary high-voltage terminals 64, 68. Namely, when the secondary terminals 64, 68 are the plus charge, the secondary terminals 66, 70 are the minus charge. The winding terminate ends 50b, 56b, 52b, 58b of the secondary terminals 50, 56, 52, 58 are respectively connected to the ground terminals 72, 76, 74, 78. Other constructions of the present embodiment are identical with the transformer shown in
In the foregoing embodiments without exception, the single C-type core is coupled to a plurality of the I type cores but, as shown in
| Number | Date | Country | Kind |
|---|---|---|---|
| JP2005-142921 | May 2005 | JP | national |
| JP2005-182184 | Jun 2005 | JP | national |