Transformer

Details Transformer Transformer

2001-02-15

2002-11-19

Mai, Anh (Department: 2832)

Inductor devices

Winding formed of plural coils

Two windings

C336S212000, C336S198000, C336S192000, C029S605000

Reexamination Certificate

active

06483411

ABSTRACT:

BACKGROUND OF THE INVENTION
This application incorporates by reference Taiwanese application Serial No. 89108056, Filed Apr. 27, 2000.
1. Field of the Invention
The invention relates in general to a transformer, and more particularly to a transformer for Liquid Crystal Display (LCD).
2. Description of the Related Art
The transformer plays an important role among various hi-tech electronic products. For example, it requires a small size transformer to energize the Cold Cathode Fluorescent Lighting (CCFL) for operating properly.
Referring to
FIGS. 1A-1C
, a top view, lateral view, and decomposed diagram of a conventional transformer for LCD is shown. The transformer
100
includes a U-core
102
, an I-bar
106
, and a bobbin
104
. The U-core
102
includes inverted U-shaped bridges
108
A and
108
B and oblong-shaped sides
110
A and
111
B. The top view of the U-core
102
is a hollow rectangle and the U-core
102
is made of a high permeable material. The bobbin
104
is made of a high-voltage endurable plastic material and capable of winding the copper coil
112
. The bobbin
104
further includes a number of pins
114
A and
114
B fixed in the Printed Circuit Board (not shown in FIGS). The I-bar
106
is a flat rectangular solid and made of high permeable material.
The stepwise sequence for assembling the transformer involves first winding the bobbin
104
with the copper coil
112
and twining the terminals of the copper coil
112
round the pins
114
A and
114
B for fastening. The I-bar
106
is then put into the hollow sleeve
116
of the bobbin
104
and the U-core
102
is mounted on the bobbin
104
. After fixing the U-core
102
, I-bar
106
, and bobbin
104
together by the epoxy
118
, the transformer
100
as shown in
FIG. 1A
is finished.
The process of producing a U-core
102
includes the following steps: a mold is first opened for the U-core
102
wherein the shapes of the mold and the U-core
102
are the same. The iron powder is filled into the mold for sintering under the pressure of injection and then shaped into the U-core
102
as shown in FIG.
1
C. Since the inverted U-shaped bridges
108
A and
108
B of the U-core
102
are pretty thin, it fails to support the ends of the sides
110
A and
110
B. Therefore, the U-core
102
might be out of shape in the sintering process of manufacture. For example, the oblong-shaped sides
110
A and
110
B of the U-core
102
might be bent outward or bent inward.
Referring to
FIG. 2
, a structural diagram of a conventional mold for producing the core is shown. The traditional way to solve the aforementioned problem is making a mold shown in FIG.
2
. As shown in
FIG. 2
, the slash part
202
is the filled portion under the bridge
108
A and
108
B. Utilizing the mold of
FIG. 2
to shape up under the pressure of injection, it can produce an iron with the same shape of the mold. Thereafter, it won't result in the iron out of shape during the sintering process due to its firm structure. The sintered iron then proceeds to be polished to become a U-core
102
of
FIG. 1C
by grinding the slash part
202
. However, it is time-consuming for precision grinding and the iron is easily broken. Thus, it cost much to produce the conventional transformer.
SUMMARY OF THE INVENTION
It is therefore an object of the invention to provide a transformer with a simple structure, which is easy to be made. In no need of the step of precision grinding to shape a core, it can raise the yield of the transformer and reduce the production cost.
The invention achieves the above-identified objects by providing a transformer capable of transforming the voltage between a first port and a second port. The transformer includes a bobbin, an I-bar, the first U-core, and the second U-core. The bobbin in a tube shape has the first port and the second port wherein the first port wrapped around by at least one winding of copper coil and the second port wrapped around by at least one winding of copper coil. An I-bar made of high permeable alloy has a first end and a second end. The I-bar is inserted into the bobbin and the first end and the second end of the I-bar protrude outside the tube of the bobbin respectively. A first U-core made of high permeable alloy is placed on one side of the bobbin and has a third end and a fourth end. The third end and the fourth end of the first U-core are placed corresponding to one side of the first end and the second end of the I-bar respectively. A second U-core made of high permeable alloy is placed on the other side of the bobbin and has a fifth end and a sixth end. The fifth end and the sixth end of the second U-core placed corresponding to the other side of the first end and the second end of the I-bar respectively. Moreover, the sunken parts of the first U-core and the second U-core are in opposition to each other.


REFERENCES:
patent: 5760670 (1998-06-01), Yeh et al.
patent: 5761670 (1998-06-01), Joy
patent: 04245607 (1992-09-01), None

Affiliated with

Also associated with

Rating

Transformer does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Transformer, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Transformer will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2994595