JPH087781A - Deflection yoke core - Google Patents

Abstract

PURPOSE:To provide a core for a deflection yoke which allows reduction of the deflecting power, decrease in the power consumption, and manufacture by the use of a conventional frame in the form of concentrical circle by giving the core a section which includes the maximum arc of circle as specified. CONSTITUTION:A deflection yoke has a section which includes the max. diametric arcs of circle ac, sc such as a radius R1 centering on the origin of X- and Y-axes and appears elliptical substantially. This section shape builds a deflection yoke core which allows reducing the deflecting power to lead to decrease in the power consumption and which can be fabricated by commonly using a conventional sintered frame 5 in concentrical circular form having a circular sintered frame opening 5a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deflection yoke core applied to a color cathode ray tube, and more particularly to a deflection yoke core having a substantially elliptical shape having different X-axis and Y-axis diameters.

[0002]

2. Description of the Related Art FIG. 7 is a perspective view showing a state in which a deflection yoke is mounted on a color cathode ray tube.

As shown in FIG. 7, a color cathode ray tube (CR
T) is composed of a panel 1, a funnel 2 and a neck tube 3 as an outer tube. The deflection yoke (DY) core 4 is provided so as to wrap the portion between the funnel 2 and the neck tube 3 from above, and deflects the electron beam emitted from the electron gun provided in the neck tube 3.

The CRT funnel 2, particularly near the neck tube, has a cone shape (conical shape) in consideration of productivity. This is because each cradle in each process in CRT manufacturing requires the same shape. Thus, the cross-sectional view near the neck tube is circular, and the center of the circle in each cross-section is the CRT.
It corresponds to the tube axis of.

Conventionally, the deflection yoke core mounted on the neck portion between the neck tube and the funnel is also a cone-shaped round core corresponding to the cone shape of the funnel 2 near the neck tube 3. FIG. 9 shows a perspective view of the round core. FIG.
1, the wide opening side is the funnel 2 side, and the narrow opening side is the neck tube 3 side. FIG. 10 shows a sectional view taken along the line CC of FIG. As shown in FIG. 10, the inner surface 4 of the round core 4 is
Also a has a cone shape. The round core, which is the deflection yoke core, includes a horizontal coil and a vertical coil.

FIG. 11 and FIG. 12 are cross-sectional views showing a round core before and after firing, respectively, when manufacturing the core of the deflection yoke. The deflection yoke core 4 is placed on the sintering frame 5. It is shown. In addition, the perspective view of the sintering rack 5 is shown in FIG. The sintering frame 5 of the core 4 holds the maximum outer diameter of one horizontal cross section of the core 4. In the case of a round core, it is held in surface contact with the inclined support wall 8 shown in FIG.

The round core has a length of 15 to 2 after firing.
Shrink 0%. The cross-sectional shape is of course the same as before the firing and since the shrinkage is equalized after the firing.

Generally, a color cathode ray tube consumes more power than a black and white cathode ray tube due to various conditions. The horizontal deflection power W of DY for deflecting the electron beam of the cathode ray tube is W
= K · D ² / L · Sin ² θ · HV. In this equation, K is a constant, D is the average diameter of the deflection yoke core, L is the average length of the deflection yoke core, and HV is CR.
The anode voltage of T is shown.

The horizontal deflection magnetic field is generated vertically in the DY as shown in FIG. When simply considering N and S magnets, the closer the magnetic poles are, the higher the magnetic flux density is.

The screen length of a television (TV) is horizontal:
Since the vertical length is a horizontal screen of 4: 3 or 16: 9, the horizontal elliptical deflection yoke core 14 increases the horizontal magnetic flux density of DY and improves the deflection efficiency as shown in FIG. Can be made.

That is, in order to reduce the deflection power W, the area of the cone portion of the core may be reduced. Therefore, 4:
A round funnel does not make sense because it draws a square raster such as 3/16: 9.

FIG. 15 shows a cross section of a conventional circular deflection yoke core 4 and an elliptic deflection yoke core 14 in comparison. In order to reduce the deflection power, an elliptical deflection yoke core effective as described above has been studied in the past.

[0013]

However, it is difficult to handle the elliptic deflection yoke core. That is, as shown in FIG. 16, when the elliptical deflection yoke core 14 is placed on the round core pedestal 5, the maximum diameter (contact portion) is formed.
Becomes a point and becomes unstable. For this reason, the conventional core frame (inner diameter is round) cannot be used for manufacturing the elliptical deflection yoke core, and a large capital investment is required.

Further, even if the core mount is made elliptical as shown by 15 in FIG. 17, it is necessary to align the X-axis / Y-axis of the elliptic deflection yoke core 14 with the X-axis / Y-axis of the mount. And productivity is poor.

Moreover, in the step of placing the elliptical deflection yoke core 14 on the sintering rack and firing it, FIG. 18 shows the elliptical deflection yoke core 14 before firing and FIG. 19 shows the elliptic deflection yoke core 14 after firing. In addition, the outer surface taper of the X-axis deflection yoke core on the major axis side is different from the outer surface taper of the Y-axis deflection yoke core on the minor axis side and their respective lengths (dimensions). Therefore, in the contraction process of the deflection yoke core 14 after firing, there is a difference between the contraction of the dimension of the X-axis part and the contraction of the dimension of the Y-axis part (the contraction rate on the X-axis side is larger than that on the Y-axis side). The dimensional accuracy of the obtained elliptical core becomes poor.

[0016] Conventionally, the applicant of the present invention has disclosed in JP-A-55-6025
4, JP-A-56-61747 and JP-A-5-
Japanese Unexamined Patent Publication No. 6-63757 discloses a funnel cone portion having a substantially elliptical shape having several arcs. That is, the ellipses related to these inventions are, for example, arcs ab and c with radius R1 centered on S and S'on the X axis, respectively.
Radius R2 centered on Q and Q'on the d and Y axes, respectively
Of arcs bc and ad. As described above, it is disclosed that the center of the conventional arc forming the ellipse is deviated from the tube axis of the CRT (the intersection point O of the X axis and the Y axis). An elliptical deflection yoke core similar to such an elliptical funnel also has the same problem of core mount as the above elliptical funnel.

In consideration of the above problems, the present invention reduces the deflection power to reduce the power consumption, and moreover, it is possible to use the conventional CRT manufacturing equipment, especially the round opening core sintered pedestal. The purpose is to provide.

[0018]

In order to solve the above problems, a deflection yoke core according to a first aspect of the present invention is a deflection yoke core having an elliptical cross-sectional outer shape with different X-axis and Y-axis diameters. It is characterized in that the circular shape includes a circular arc having a maximum diameter centered on the coordinate origin of the X axis and the Y axis.

A deflection yoke core according to a second aspect of the present invention is the deflection yoke core according to the first aspect, wherein at least two arcs centering on the coordinate origins of the X-axis and the Y-axis are provided opposite to the coordinate origins. It is characterized by

[0020]

According to the present invention, the cross-sectional outer shape of the deflection yoke core 24 is an elliptical shape having different X-axis and Y-axis, and the elliptical shape is an arc having the maximum diameter centered on the coordinate origin O of the X-axis and the Y-axis. It is possible to reduce the deflection power because it contains
As the cradle for manufacturing the core, the conventional concentric core pedestal 5 can provide sufficient surface contact.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

The deflection yoke core of the present invention is mainly intended for a color cathode ray tube provided with a conventional so-called in-line multi-beam type electron gun such as an in-line array 3 electron gun or a single electron gun 3 electron beam type as an electron gun. To do. Further, FIG. 3 shows the outer shape of the oval deflection yoke core 24 of FIG.

As shown in FIGS. 1 and 2, the deflection yoke core has a large opening 25a on the funnel side and a small opening 2 on the neck tube side.
5b, the outer diameter of the small opening 25b is substantially circular, but on the funnel side, the outer shape is mainly a as shown in FIG.
It has an oval shape as shown by four arcs b, bc, cd, and da. In particular, the arcs ab and cd are arcs having a radius R1 centered on the coordinate origin O of the X axis and the Y axis, respectively, and have the same length, and are provided so as to face each other and cut the X axis. On the other hand, the arcs bc and da are centered around the symmetrical points S and S'on the Y-axis, have the same length as the arcs of radius R2, and are provided so as to cut the Y-axis oppositely.

When the intersections of the arcs bc and da with the Y axis are P and Q, respectively, OP (OQ) <R1. Therefore, this deflection yoke core can make the volume of the cone portion smaller than that of the round core, and N and S. Since the magnetic poles can be brought close to each other, the deflection power can be reduced.

In the first embodiment of the present invention, as shown in FIG. 4, a sufficient amount of circular arcs ab and cd are provided on a sintered mount (core mount) 5 having a round sintered mount opening 5a of radius R1. Contact is made. That is, the elliptic deflection yoke core of the first embodiment can use the conventional round core mount.

Next, a second embodiment of the oval core will be described with reference to FIGS. 5 and 6. FIG. 5 is a view showing the outer shape of the second embodiment, and the second embodiment has arcs ef, fg, gh, h.
It has an oval shape composed of i, ij, jk, km, and me, and among these four arcs ef, gh, ij, and km, radii are R3 around the intersection (origin) O of the X axis and the Y axis.
And the arcs fg and jk are points T and T ′ on the X axis.
Is a circular arc with a radius of R4, and the circular arcs hi and me are circular arcs with a radius of R5 centered on the points U and U'on the Y axis.

As described above, the oval deflection yoke core of the second embodiment also includes four arcs (ef, gh, ij, km) whose elliptical shape is centered on the origin O of the X axis and the Y axis. The radius R4 of these four arcs is larger than the distance from the origin O to other arcs, such as hi and jk.

FIG. 6 is a diagram showing a state in which the second embodiment is applied to a conventional round opening core mount 5. As shown in FIG. 6, the elliptical deflection yoke core 34 of the second embodiment contacts the surface of the round shaped pedestal opening 5a of the pedestal 5 at the arcs ef, gh, ij, km of the maximum diameter portion. Supported by. As described above, since the present embodiment also has an arc centered on the origin O, the conventional round core mount can be used.

In the first and second embodiments described above, it was shown that the conventional round core pedestal can be used in the manufacturing line, but if the funnel outer shape itself is made elliptical, the deflection of the electron beam can be prevented. Therefore, the deflection power can be reduced, and the deflection sensitivity can be improved.

Although two arcs in the first embodiment and four arcs in the second embodiment are arranged on the deflection yoke core as part of the arc centered on the origin O of the X-axis and Y-axis of the oval,
The length and number of arcs centering on the origin O need only be such that the deflection yoke core can be stably arranged on the conventional round core mount.

[0031]

As described above, according to the present invention,
Since the shape of the deflection yoke core placed in the neck tube portion near the funnel of the color cathode ray tube, that is, the cross-sectional outer shape cut along the plane orthogonal to the tube axis can be made oval, the deflection power can be reduced and the power consumption can be reduced. Can contribute.

In addition, according to the present invention, since the conventional core mount having the round opening having the same diameter as the maximum diameter of the arcs having the origin O as the center which constitutes the outer shape of the deflection yoke core can be used, the conventional manufacturing method can be used. The equipment can be shared, and the deflection yoke (DY) can also be attached to the conventional round DY.

[Brief description of drawings]

FIG. 1 is a perspective view showing a first embodiment of an oval deflection yoke core according to the present invention.

FIG. 2 is a cross-sectional view taken along the line AA and the line BB in FIG.

FIG. 3 is a diagram for explaining the outer shape of the first embodiment.

FIG. 4 is a diagram showing a state in which the first embodiment of the present invention is applied to a conventional round core mount.

FIG. 5 is a diagram for explaining the outer shape of the second embodiment of the oval deflection yoke core according to the present invention.

FIG. 6 is a diagram showing a state in which a second embodiment of the present invention is applied to a conventional round-shaped open core cradle.

FIG. 7 is a perspective view showing a state in which a deflection yoke core is attached to a color cathode ray tube (CRT).

FIG. 8 is a diagram showing a round funnel and horizontal deflection power.

FIG. 9 is a perspective view showing a conventional round deflection yoke core.

10 is a cross-sectional view taken along line CC of FIG.

FIG. 11 is a cross-sectional view showing a round deflection yoke core before firing on a sintering rack.

FIG. 12 is a cross-sectional view showing a circular deflection yoke core after firing on a sintering rack.

FIG. 13 is a perspective view of a sintering rack.

FIG. 14 is a sectional view of a conventional elliptical deflection yoke core.

FIG. 15 is a diagram showing a conventional round deflection yoke core and an elliptical deflection yoke core.

FIG. 16 is a diagram showing a state in which an elliptic deflection yoke core is applied to a round core mount.

FIG. 17 is a diagram showing a state in which an elliptic deflection yoke core is applied to an elliptic aperture core mount.

FIG. 18 is a cross-sectional view showing an elliptical deflection yoke core before firing on a sintering rack.

FIG. 19 is a cross-sectional view showing an elliptical deflection yoke core after firing on a sintering rack.

[Explanation of symbols]

 1 panel 2 funnel 3 neck tube 3b neck tube inner diameter 4 deflection yoke core 5 sintered mount (core mount: round opening) 5a core mount (round) opening 14 elliptical deflection yoke core 15 core mount (ellipse opening) 15a core mount ( Oval) opening

Claims (2)

[Claims] 1. A deflection yoke core having a cross-sectional outer shape of an elliptical shape having different diameters on the X-axis and the Y-axis, wherein the elliptical shape includes an arc having a maximum diameter centered on a coordinate origin of the X-axis and the Y-axis. A deflection yoke core characterized in that 2. The deflection yoke core according to claim 1, wherein at least two arcs centering on the coordinate origins of the X-axis and the Y-axis are provided facing each other with respect to the coordinate origins.