Winding – tensioning – or guiding – Composite article winding – On irregularly shaped core
Reexamination Certificate
2000-10-13
2002-11-26
Matecki, Kathy (Department: 3653)
Winding, tensioning, or guiding
Composite article winding
On irregularly shaped core
C242S439000
Reexamination Certificate
active
06484960
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to a coil winding machine suitably used to wind a conducting wire of a deflection coil on a coil bobbin in a saddle type and a method of producing a deflection coil by using the coil winding machine.
In color cathode ray tubes (hereinafter, referred to as “color CRTs”), three electron beams emitted from an electron gun are deflected in the vertical and horizontal directions to display a color image on a screen.
A deflection yoke having a horizontal deflection coil and a vertical deflection coil is used for deflecting electron beams.
The deflection yoke is mounted on a cone portion extending from a neck portion and a funnel portion of a CRT.
The deflection yoke forms a deflection magnetic field by making a horizontal deflection current flow in the horizontal deflection coil and also making a vertical deflection current flow in the vertical deflection coil, to deflect electron beams in the vertical and horizontal directions by the deflection magnetic field.
The three electron beams thus deflected are converged at one point of a color selection electrode (aperture grill or shadow mask), thereby to reproduce a desired color image on the screen.
By the way, in recent years, there have been strong demands toward higher accuracy of TV sets, computer displays, and the like.
In particular, to realize the enlargement of a display screen for TV sets and also realize the display of high-definition images for computer displays, the deflection frequency of electron beams has become increasingly higher.
Further, to reduce distortion and unnecessary reflection from the exterior at a peripheral portion of the screen of a CRT, flattening of the panel of the CRT has been developed.
A CRT having a flattened panel (hereinafter, referred to as “flat panel CRT”), however, has an inconvenience that since the distance between a deflection yoke and each of the right and left ends becomes longer, it becomes very difficult to ensure the convergence of electron beams in combination of reduction in raster distortion only by a deflection distribution generated by the deflection yoke.
At present, TV sets and computer displays using flat panel CRTs have been commercially available.
In such a flat panel CRT, however, if the convergence of electron beams in combination of reduction in raster distortion cannot be obtained only by a deflection magnetic field generated by a deflection yoke, it must be realized by using a complicated correction circuit or performing difficult adjustments.
On the other hand, from the viewpoint of electric characteristic, as the number of turns of a conducting wire of a deflection coil becomes larger, it becomes harder for a current with a high frequency to flow in the conducting wire.
Accordingly, to increase a deflection frequency of electron beams, it is required to reduce the number of turns of a conducting wire of a deflection coil.
The reduction in the number of turns of a conducting wire means that the field strength per one turn of the conducting wire becomes large to raise the sensitivity.
As a result, a deviation in winding position of a conducting wire exerts a large effect on the deflection magnetic field distribution of a deflection coil.
For this reason, as the deflection frequency of electron beams becomes, it is strongly required to make higher the accuracy of a winding distribution of a deflection coil higher.
FIGS. 1A
to
1
H are schematic views showing a coil winding procedure for producing a saddle type deflection coil by using a related art coil winding machine.
First, as shown in
FIG. 1A
, a nozzle
52
placed inside a coil bobbin
51
is moved up along the inner peripheral surface of the coil bobbin
51
while feeding out a conducting wire W.
As shown in
FIG. 1B
, at a position near an opening of the nozzle
52
, which has been moved above the coil bobbin
51
, an upper hook
53
is turned into a “close” position to catch the conducting wire W by the tip of the hook
53
.
The hook
53
is then moved outside the coil bobbin
51
while the conducting wire W is fed out of the nozzle
52
.
As shown in
FIG. 1C
, the coil bobbin
51
is rotated, to wind the conducting wire W in a circumferential guide groove (not shown) of the coil bobbin
51
.
When the winding angle of the conducting wire W reaches a specific angle, the rotation of the coil bobbin
51
is stopped, and, in this state, the hook
53
is turned into an “open” position to release the conducting wire W from the tip of the hook
53
.
As shown in
FIG. 1D
, inside the coil bobbin
51
, the nozzle
52
is moved down along the inner peripheral surface of the coil bobbin
51
while feeding out the conducting wire W.
As shown in
FIG. 1E
, at a position near the opening of the nozzle
52
, a lower hook
54
is turned into the close position to catch the conducting wire W by the tip of the hook
54
.
As shown in
FIG. 1F
, the hook
54
is moved outside the coil bobbin
51
while the conducting wire W is fed out of the nozzle
52
.
Then, as shown in
FIG. 1G
, the coil bobbin
51
is rotated in the direction reversed to the rotational direction at the step shown in
FIG. 1C
, to wind the conducting wire W in the circumferential guide groove (not shown) of the bobbin
51
.
When the winding angle of the conducting wire W reaches a specific angle, the rotation of the coil bobbin
51
is stopped.
In such a state, the hook
54
is turned into the open position to release the conducting wire W from the tip of the hook
54
.
The conducting wire W has been thus wound by one turn.
Next, the nozzle
52
is moved up again, as shown in FIG.
1
H. After that, the above-described operation is repeated while the winding position of the conducting wire W on the inner peripheral side of the coil bobbin
51
is sequentially shifted in the circumferential direction of the coil bobbin
51
.
In this way, the conducting wire W for a deflection coil is wound around the coil bobbin
51
in a saddle type.
The above-described related art coil winding machine performs, as shown in
FIG. 2
, the operation of catching the conducting wire W by the tip of the hook
53
and the operation of releasing the conducting wire W from the tip of the hook
53
by turning the hook
53
in direction A into the open position and the close position, respectively.
Accordingly, upon feeding the conducting wire W having been wound in the circumferential guide groove
56
of the coil bobbin
51
in one of slits
58
formed by a plurality of ribs
57
, it is required to ensure an operational space S for turning the hook
53
into the open position.
To be more specific, the conducting wire W is released from the hook
53
at a position P
2
offset from a position P
1
, at which the conducting wire W is to be finally placed, by an amount equivalent to the operational space S in the direction from inside to outside of the coil bobbin
51
.
Accordingly, the movement of the conducting wire W is not restricted in a distance L between the position P
1
at which the conducting wire W is to be finally placed and the position P
2
at which the conducting wire W is released from the hook
53
.
As a result, after the winding of the conducting wire W is completed, as shown in
FIG. 3
, there occur variations in winding position between the conducting wire W portions wound in each slit
58
in the circumferential guide groove
56
. This makes it very difficult to increase the accuracy of a winding distribution of the deflection coil.
On the other hand, the winding of the conducting wire W on the coil bobbin
51
can be performed only by operation of the nozzle
52
without use of the above-described hook
53
; however, in this case, the coil bobbin
51
itself must have the function of guiding the conducting wire W.
As a result, the force applied to each rib
57
formed on the coil bobbin
51
becomes larger.
In particular, upon feeding the conducting wire W to each slit
58
, as shown in
FIG. 4
, the conducting wire W withdrawn on the inner peripheral side of the coil bobbin by the nozzle
52
is brought into c
Kananen, Esq. Ronald P.
Matecki Kathy
Rader & Fishman & Grauer, PLLC
Sony Corporation
LandOfFree
Coil winding machine and method of producing deflection coil does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Coil winding machine and method of producing deflection coil, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Coil winding machine and method of producing deflection coil will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2992785