JP2000294165A - Deflection yoke and core for deflection yoke - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a deflection yoke capable of reducing power by the improvement of deflection efficiency and resolving defects in manufacturing a core at the same time. SOLUTION: In this deflection yoke provided with a core 10 having a cylindrical structure of which one end is opened with a diameter larger than that of the other end, the outside surface 13 of the core 10 is formed into a circular cross-sectional shape from the large-diameter opening part 11 through the small- diameter opening part 11, and the inside surface 14 of the core 10 is formed into a generally rectangular cross-sectional shape on the large-diameter opening part 11 side. By virtue of this structure, the deflection coil can be arranged close to an effective magnetic field region, and a conventional jig can be used as it is in a sintering process in manufacturing the core. Thereby, the reduction of consumption power by the improvement of deflection efficiency and elimination of defects in manufacturing the core can be achieved at the same time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a deflection yoke and a deflection yoke core used for a cathode ray tube for a television or a computer display.

[0002]

2. Description of the Related Art Generally, in a cathode ray tube, an image is assembled on a screen by deflecting a traveling direction of an electron beam emitted from an electron gun up and down and left and right. A deflection yoke having deflection coils (a vertical deflection coil and a horizontal deflection coil) is used to deflect the electron beam.

[0003] The deflection yoke is mounted on a portion called a cone portion from the neck portion of the cathode ray tube to the funnel portion. Then, the electron beam emitted from the electron gun is moved up and down by the electromagnetic action of the deflection current flowing through the deflection coil.
Deflected left and right.

Conventionally, the cross-sectional shape of a core for a coil winding, which is a component of a deflection yoke, is circular, similar to the cross-sectional shape of a cone portion of a cathode ray tube to which the coil is mounted. FIG.
FIG. 1 shows a conventional core structure having a circular cross-sectional shape, in which (a) is a side half-sectional view and (b) is a front view. The illustrated core 30 has a cylindrical structure as a whole, and has one opening 31 to the other opening 3.
The two inner and outer surfaces 33 and 34 have a circular cross-sectional shape.

On the other hand, since the screen of the cathode ray tube has a rectangular shape, the area of the deflection magnetic field necessary for scanning the electron beam on this screen has a rectangular cross section. In such a case, if the cross-sectional shape of the core of the deflection yoke is circular, the deflection coil forms a magnetic field at a position distant from an area that actually requires a deflection magnetic field (hereinafter, referred to as an effective magnetic field area). During that time, an invalid magnetic field is formed. Accordingly, the deflection power is consumed more by that amount.

Therefore, in recent years, the cross-sectional shape of the cone portion of the cathode ray tube has been made rectangular (square), and the deflection yoke mounted on the cone portion (hereinafter referred to as a square cone portion) has a rectangular shape including the core. Are presented.

FIG. 4 shows a conventional core structure having a rectangular cross-sectional shape. FIG.
(B) is a front view thereof. The illustrated core 40 has a cylindrical structure as a whole, and has a rectangular cross-section on both the inner and outer surfaces 42 and 43 on one opening 41 side.
On the other opening 44 side, both the inner and outer surfaces 42 and 43 have a circular cross-sectional shape.

By employing the core 40 having such a cross-sectional shape, the effective magnetic field region and the deflection coil can be arranged close to each other. As a result, the ineffective magnetic field can be reduced and the deflection efficiency can be increased, so that the power consumption can be reduced.

[0009]

However, changing the sectional shape of the core of the deflection yoke as described above has the following disadvantages.

That is, in the manufacturing process of the core, first, the raw material (soft ferrite material or the like) of the core is poured into a mold and molded, and then the obtained molded product is put into an electric furnace in a sintering process and heated for a long time. I do. At that time, in the sintering step, a ring-shaped jig is used to regulate the external shape of the molded product from the outside and to increase the filling efficiency by stacking the molded products.

However, when the cross-sectional shape of the core (particularly, the cross-sectional shape of the outer surface of the core) is changed as described above, the jig used in the sintering process cannot be used. For this reason, the filling efficiency in the electric furnace is extremely deteriorated, and the production cost is increased. In addition, since the outer shape of the molded product cannot be regulated by the jig, the variation in the core shape becomes large.

Further, new equipment investment is required to prepare a jig that matches the cross-sectional shape (rectangle) of the outer surface of the core. Even if a new jig is manufactured, if the core has a rectangular cross-sectional shape, the molded product will shrink unevenly during the sintering process, causing distortion in the core shape after sintering. Quality control becomes very difficult.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and an object of the present invention is to provide a deflection device capable of simultaneously reducing power consumption by improving deflection efficiency and eliminating defects in core manufacturing. A yoke and a deflection yoke core are provided.

[0014]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above-mentioned object, and a deflection yoke provided with a cylindrical core having one opening with a larger diameter than the other. Has a circular cross-sectional shape from one (large-diameter opening) to the other (small-diameter opening), and the inner surface of the core has a substantially rectangular cross-sectional shape on at least one (large-diameter opening) side.

The present invention also provides a deflection yoke core having a cylindrical structure in which one is opened with a larger diameter than the other.
The outer surface is changed from one (large-diameter opening) to the other (small-diameter opening)
And a substantially rectangular cross-sectional shape on at least one (large-diameter opening) side.

In this deflection yoke and the deflection yoke core, the outer surface of the core has a circular cross-sectional shape from one (large-diameter opening) to the other (small-diameter opening), so that the sintering in manufacturing the core is performed. In the process, a conventional jig can be used as it is. In addition, since the inner surface of the core has a substantially rectangular cross-sectional shape on at least one (large-diameter opening) side, when the deflection yoke is mounted on a cathode ray tube having a square cone, the core is deflected with respect to the effective magnetic field region. It is possible to arrange the coils in the proximity state.

[0017]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1A and 1B illustrate a deflection yoke according to an embodiment of the present invention, in particular, a core structure as a component thereof. FIG. 1A is a half sectional view of a side surface, and FIG. 1B is a front view thereof. .

The illustrated core 10 has a cylindrical structure with one and the other open. One opening 11 has a larger diameter than the other opening 12. The deflection yoke having the core 10 has a large-diameter opening (hereinafter, referred to as a large-diameter opening) 11 on the panel side and a small-diameter opening (hereinafter, referred to as a small-diameter opening) 12 on the electron gun side. It is mounted on the cone part of the cathode ray tube with it turned.

The outer surface 13 of the core 10 has a circular cross-sectional shape from one side to the other side, and its outer diameter gradually decreases from the large-diameter opening 11 to the small-diameter opening 12. That is, the outer surface 13 of the core 10 is formed in a substantially conical cylindrical shape.

On the other hand, the inner surface 14 of the core 10 has a substantially rectangular (square) cross-sectional shape on the large-diameter opening 11 side.
The small-diameter opening 12 has a substantially circular cross-sectional shape.

More specifically, the large-diameter opening 11 of the core 10 has an upper side 11a and a lower side 11b having a horizontal axis X of the core.
Are formed parallel and linear to each other at a position equidistant from
The left side 11c and the right side 11d are formed in parallel with each other at a position equidistant from the vertical axis Y of the core and linearly. The upper and lower sides 11a and 11b and the left and right sides 11c and 11d are formed so as to be at right angles to each other.
Both ends of a, 11b, 11c and 11d are connected in a semicircle (R shape) with a predetermined radius. Thus, the large-diameter opening 11 of the core 10 is formed in a substantially rectangular shape with the center axis Z of the core as a reference (center).

On the other hand, the small-diameter opening 12 of the core 10 is formed in a substantially perfect circle with respect to the center axis Z of the core (center). The inner surface 14 of the core 10 has a cross-sectional shape
It is formed so as to gradually change from a rectangular shape to a circular shape from the large-diameter opening 11 to the small-diameter opening 12. Thus, the inner surface 14 of the core 10 has a substantially rectangular cross-sectional shape on the large-diameter opening 11 side and a substantially circular cross-sectional shape on the small-diameter opening 12 side.

In the deflection yoke provided with such a core 10, when the deflection yoke is mounted on a cathode ray tube having a square cone portion, the inner surface 14 of the core 10 has a substantially rectangular cross-sectional shape at the large-diameter opening 11 side. Therefore, it is possible to arrange the deflection coil close to the effective magnetic field region. Thereby, the ineffective magnetic field can be reduced and the deflection efficiency can be increased, so that the power consumption can be reduced.

In manufacturing the core 10,
Since the outer surface 13 of the core 10 has a circular cross-sectional shape from one (large-diameter opening 11) to the other (small-diameter opening 12), in the sintering process, even if a new jig is not newly manufactured, Can be used as it is. In addition, the manufacturing cost can be reduced by avoiding deterioration of the filling efficiency in the electric furnace in the sintering step, and the outer shape of the core can be suppressed by regulating the outer shape of the molded product by using a jig. Furthermore, since the shrinkage of the molded product in the sintering process becomes uniform, distortion and the like are hardly generated in the core outer shape,
Therefore, quality control becomes easy.

FIG. 2 illustrates a deflection yoke according to another embodiment of the present invention, in particular, a core structure as a component thereof. FIG. 2 (a) is a side half sectional view of the deflection yoke, and FIG.
Is a front view thereof.

The illustrated core 20 has a cylindrical structure in which one and the other are open as in the previous embodiment. The deflection yoke having the core 20 has a large-diameter opening (hereinafter, referred to as a large-diameter opening) 21 on the panel side and a small-diameter opening (hereinafter, referred to as a small-diameter opening) 22 on the electron gun side. It is mounted on the cone part of the cathode ray tube with it turned.

The outer surface 23 of the core 20 has a circular cross-sectional shape from one side to the other side, and its outer diameter gradually decreases from the large-diameter opening 21 to the small-diameter opening 22. That is, the outer surface 23 of the core 20 is formed in a substantially conical cylindrical shape as in the previous embodiment.

On the other hand, the inner surface 24 of the core 20 has a substantially rectangular (square) cross-sectional shape on the large-diameter opening 21 side.
The small-diameter opening 22 has a substantially circular cross-sectional shape.

More specifically, the large-diameter opening 21 of the core 20 has an upper side 21a and a lower side 21b whose vertical axis Y
The left side 21c and the right side 21d are formed in an arc shape with a second radius R2 having a center point on the horizontal axis X of the core. Here, each of the first and second radii R1 and R2 is set to be larger than the maximum outer radius R0 of the core 20. In addition, each side 21a, 21b, 21c, 2
Both ends of 1d are connected in a substantially semicircular shape (R shape) with a radius R3 smaller than the first and second radii R1, R1. Thus, the large-diameter opening 21 of the core 20 is formed in a substantially rectangular shape with the center axis Z of the core as a reference (center).

On the other hand, the small-diameter opening 22 of the core 20 is formed in a substantially perfect circle with the center axis Z of the core as a reference (center). The inner surface 24 of the core 20 has a cross-sectional shape
It is formed so as to gradually deform from a rectangular shape to a circular shape from the large-diameter opening 21 toward the small-diameter opening 22. Thus, the inner surface 24 of the core 20 has a substantially rectangular cross-sectional shape on the large-diameter opening 21 side and a substantially circular cross-sectional shape on the small-diameter opening 22 side.

In the deflection yoke provided with such a core 20, the inner surface of the core 20 has a substantially rectangular cross-sectional shape on the side of the large-diameter opening 21 and the outer surface of the core 20 extends from the large-diameter opening 21 to the small-diameter opening. Since the section 22 has a circular cross-sectional shape, the power consumption can be reduced by improving the deflection efficiency and the problem in manufacturing the core can be eliminated at the same time as in the previous embodiment.

In the above embodiment, the inner surface of the core has a substantially rectangular cross-sectional shape only on the large-diameter opening side, and a substantially circular cross-sectional shape on the small-diameter opening side. However, the present invention is not limited to this. The inner surface of the core may have a substantially rectangular cross-sectional shape from one (large-diameter opening) to the other (small-diameter opening).

Incidentally, at present, even in a cathode ray tube having a rectangular cone portion, the cross-sectional shape of the neck portion connected to the cone portion is circular, so that the deflection yoke provided with the core according to the above embodiment is suitable. It is possible to correspond to. In the future, when a cathode ray tube having both a cone portion and a neck portion having a rectangular cross-sectional shape is provided, the inner surface of the core will have a substantially rectangular cross-sectional shape over the entire area (from one side to the other side) in accordance with the cross-sectional shape. By adopting a core that
It becomes possible to respond appropriately.

[0034]

As described above, according to the present invention, the outer surface of the core is changed from one (large-diameter opening) to the other (small-diameter opening).
And the inner surface of the core has a substantially rectangular cross-sectional shape on at least one (large-diameter opening) side, so that the deflection coil can be arranged close to the effective magnetic field region. At the same time, a conventional jig can be used as it is in the sintering step when manufacturing the core. As a result, it is possible to simultaneously reduce the power consumption by improving the deflection efficiency and eliminate the problem in manufacturing the core.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a core structure of a deflection yoke according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a core structure of a deflection yoke according to another embodiment of the present invention.

FIG. 3 is a diagram showing a core structure of a conventional deflection yoke.

FIG. 4 is a view showing another core structure of a conventional deflection yoke.

[Explanation of symbols]

10, 20 ... core, 11, 21 ... large-diameter opening, 12, 2
2 ... Small diameter opening, 13,23 ... Outer surface, 14,24 ... Inner surface

Claims (2)

[Claims] 1. A deflection yoke provided with a core having a cylindrical structure in which one is opened with a larger diameter than the other, wherein the core has an outer surface having a circular cross-sectional shape from the one to the other, and an inner surface thereof. Has a substantially rectangular cross section at least on one side. 2. A deflection yoke core having a cylindrical structure in which one is opened with a larger diameter than the other, wherein an outer surface has a circular cross-sectional shape from said one to said other, and an inner surface thereof has at least one of said one side. 3. The deflection yoke core according to claim 1, wherein the deflection yoke has a substantially rectangular cross section.