Apparatus using double focusing type fly-back transformer

Details Apparatus using double focusing type fly-back transformer Apparatus using double focusing type fly-back transformer

1998-08-14

2001-03-06

Ham, Seungsook (Department: 2878)

Electric lamp and discharge devices: systems

Cathode ray tube circuits

Power supply from deflection circuit source

C336S145000, C327S538000

Reexamination Certificate

active

06198237

ABSTRACT:

BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an apparatus using a double focusing type fly-back transformer. Particularly, the present invention relates to an apparatus using a double focusing type fly-back transformer, in which a top bleeder type is adopted in drawing the focus voltage of the fly-back transformer instead of the conventional neutral point type, the double patterns of the focus resistors are separated from each other instead of the conventional common connections to the ground on the substrate FUB of a focus unit part, and one or more of the separately installed focus resistor patterns is used as a feedback line together with the bleeder resistor, thereby drastically reducing the size of the substrate of the bleeder resistor.
2. Description of the Prior Art
FIG. 1
is a perspective view showing the external shape of the general double focusing type fly-back transformer. Referring to
FIG. 1
, the double focusing type fly-back transformer is generally used in televisions and computer monitors to supply an anode voltage, a double focus voltage and a screen voltage. In the double focusing type fly-back transformer
10
of
FIG. 1
, reference code VOLH indicates an adjusting volume for a horizontal focus voltage, VOLV indicates an adjusting volume for a vertical focus voltage, and VOLG indicates an adjusting volume for a screen voltage. Further, reference code CA
0
indicates a cable for supplying an anode voltage to an anode of the monitor, and CA
1
, CA
2
and CA
3
indicates cables for supplying a horizontal focus voltage, vertical focus voltage and a screen voltage to respective grids of an electron gun. Reference code CAP indicates an anode cap.
FIG. 2
is a circuit diagram showing the circuital constitution of the apparatus using the conventional double focusing type fly-back transformer. Referring
FIG. 2
, in the conventional double focusing type fly-back transformer
10
, a horizontal outputting part
5
includes a transistor Q
1
, a damper diode DD and a tuning capacitor CT. The horizontal outputting part
5
operates in accordance with horizontal synchronizing signals to generate pulses in a primary winding L
1
of the fly-back transformer. The pulse type ac voltages of the primary winding L
1
are stepped up, rectified and flattened by secondary windings L
11
, rectifying diodes D
11
-D
16
and a high voltage capacitor C
11
. The fly-back transformer which operates in this manner supplies an anode voltage, and supplies a double focus voltage and a screen voltage through the focus unit part.
The double focusing type fly-back transformer
10
includes: a primary winding L
1
with its one end connected to an output terminal of a horizontal outputting part
5
, and with its another end connected to a power source B+, for obtaining collector pulses through LC-resonances of the horizontal outputting part
5
; secondary windings L
11
-L
16
for stepping up the pulse type ac voltages in accordance with the winding ratios of them to the primary winding L
1
; rectifying diodes D
11
-D
16
for rectifying the ac voltages of the secondary windings; a high voltage capacitor C
11
for flattening the rectified dc voltage; a bleeder resistor BR
1
for sensing the CPT (color picture tube) discharge and the high voltage fluctuations at a set-off status; and a focus unit part for supplying two focus voltages (double focus voltage) and a screen voltage by utilizing a neutral point (upon D
12
) of the secondary windings L
11
-L
16
. Further, an iron core FC is disposed between the primary winding L
1
and the secondary windings L
11
-L
16
.
The focus unit part is used on a large monitor of over 17 inches. This part is a double focus unit for supplying a horizontal focus voltage and a vertical focus voltage, and includes: serially connected fixed and first variable resistors R
11
and VR
11
for outputting the horizontal focus voltages to a horizontal focus voltage output terminal FH; serially connected fixed and second variable resistors R
12
and VR
12
for outputting the vertical focus voltages to a vertical focus voltage output terminal FV; and a third variable resistor VR
13
connected between the connection point of the resistors R
11
and R
12
and a grounded first connection pint #
11
, for outputting the screen voltage to a screen voltage output terminal G
2
.
Meanwhile, the fly-back transformer
10
further includes: a coupling capacitor CP for outputting parabolic pulses 300V
p-p
(supplied from the set through a second connection pin #
12
) onto the vertical focus voltage (about 4.5 KV-8.5 KV), the vertical voltage being outputted through the vertical focus voltage output terminal FV; and a bypass capacitor CB for bypassing to the ground the ac noise components such as the parabolic pulses contained in the horizontal focus voltage outputted through the horizontal focus voltage output terminal FH.
Further, in order to feed back the voltage to be compensated to the power source B+ in accordance with the high voltage fluctuations after detecting the high voltage fluctuations in the output of the fly-back transformer, the set side includes: a capacitor C
13
connected between the ground and a high voltage capacitor C
11
through a fourth connection pin #
14
; a capacitor C
12
connected between a capacitor C
11
and a bleeder resistor BR
1
through a third connection pin #
13
; an initial voltage setting part
12
for voltage-dividing the anode voltage (a high voltage) through the bleeder resistor BR
1
and its internal resistors; and a high voltage stabilizing circuit part
11
for compensating the power source B+ by feeding back the voltage of the initial voltage setting part
12
.
FIG. 3
illustrates the printed patterns formed on the substrate FUB of the focus unit part of the double focusing type fly-back transformer of FIG.
2
. Referring
FIG. 3
, the conventional substrate FUB of the focus unit part is a ceramic board, and a resistor PF is formed on the ceramic board. Here, reference codes PCA
1
-PCA
3
indicate connection points for cables CA
1
-CA
3
. Reference codes PVOLH, PVOLV and PVOLG indicate volume connection points for adjusting volumes VOLH, VOLV and VOLG. Reference codes PCP and PCB indicate capacitor connection points for the coupling capacitor CP and the bypass capacitor CB. Reference code PD
12
indicates a diode connection point to be connected to the diode D
12
, and P
11
indicates a connection point for a first connection pin.
FIG. 4
illustrates the contour of the bleeder resistor BR
1
of FIG.
2
. Referring to
FIG. 4
, the conventional bleeder resistor BR
1
has dimensions of about 15 mm×50 mm, and is formed by forming a printed pattern BRP
1
upon a ceramic substrate BRB
1
. Reference code L
13
indicates a lead line to be connected to a third connection pin #
13
, and LPH indicates a lead line to be connected to a connection point PH of an anode voltage output line. The fly-back transformer contains the bleeder resistor BR
1
and the high voltage capacitor C
11
with the same sizes. The fly-back transformer further includes the FUB and a bypass capacitor CB and a coupling capacitor CP connected to the FUB.
The conventional double focusing fly-back transformer constituted as above will now be described as to its operations.
First, referring to
FIG. 2
, the horizontal outputting part
5
which includes the horizontal output transistor Q
1
, the damper diode DD and the tuning capacitor CT operates within a range of 15-100 KHz in accordance with the horizontal synchronizing signals. The primary winding L
1
which is connected between the output terminal of the horizontal outputting part
5
generates pulse type ac voltages. These ac voltage of the primary winding L
1
are stepped up by the secondary windings L
11
-L
16
, and then, the ac voltages are rectified into a dc voltage. Then this dc voltage is flattened by the high voltage capacitor C
11
, and thus, a dc voltage of about 26 KV is outputted through an anode voltage output terminal HV to an anode te

Affiliated with

Also associated with

Rating

Apparatus using double focusing type fly-back 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 Apparatus using double focusing type fly-back transformer, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus using double focusing type fly-back transformer will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2473395