JPS6119032A - Deflection yoke - Google Patents

Abstract

PURPOSE:To improve horizontal deflection sensitivity by so forming a core of a deflection yoke that the length of an air gap of its inside may be shorter on the vertical axis than on the horizontal axis while the grooves may be shallower in the position having the greater angle to the vertical axis. CONSTITUTION:The core 4 is so formed that the air gap length lV on the vertical axis 8 of its inside surface may be shorter than the air gap length lH on the horizontal axis 9 while the grooves 4a are so formed that their bases may be on the concentric circles and the salient parts 4b may be shorter the greater angles theta they may form with the vertical axis 8. And a vertical deflection coil 3 is toroidally wound about the grooves 4a while providing a horizontal deflection coil 2 inside the core 4 through a separator 5 for forming a deflection yoke 1 to be used by being mounted on a cathode-ray tube. Accordingly, the horizontal deflection sensitivity can be improved and a spiral current loss in the vertical deflection coil can be reduced by an action of strengthening only a magnetic field contributing to horizontal deflection and weakening the magnetic field crossing the vertical deflection coil.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a deflection yoke for a cathode ray tube.

[Background of the invention]

Conventional deflection yokes used in horizontal deflection systems with high deflection frequencies used in high-definition displays, etc.
As shown in FIG. 1(a) and FIG. 2 (a) and (b) As shown in FIG. 2, a horizontal deflection coil 2 and a vertical deflection coil 6 are attached to a core 4 having a groove 4a of a constant depth on its inner surface (hereinafter referred to as a slot core), respectively. There are saddles that are wound around the shape and those that have a saddle-shaped structure. The horizontal deflection sensitivity expressed by the eddy current produced when the high-frequency horizontal deflection magnetic field 7 crosses the vertical deflection coil 3 and LI2 (L: inductance of the horizontal deflection coil, I: horizontal deflection current) is shown in Figure 2. In the case of the slot core, the horizontal deflection magnetic field 7 forms a magnetic path passing through the protrusion 4b of the core, making it possible to reduce the magnetic flux density across the vertical deflection coil 3 and shorten the magnetic path length l of the air gap. It has less eddy current and better horizontal deflection sensitivity than the deflection yoke shown in Figure 1. However, as shown in Fig. 2 (6), the inductance of the horizontal deflection coil 2 increases due to the magnetic flux 7a of the magnetic path that does not contribute to deflection, so the horizontal deflection sensitivity decreases as the difference in the magnetic path length l of the air gap increases. Doesn't improve.

On the other hand, in terms of structure, in the case of the deflection yoke 1 shown in FIG.
In order to embed the deflection yoke 1 in FIG.
It is not possible to assemble the horizontal deflection coil 2 by a simple method such as first insulating it with an insulator (separator) 5 and assembling it, and then providing the vertical deflection coil 3 and the core 4 on the outer periphery of the horizontal deflection coil 2 later. Furthermore, in the case of the deflection yoke shown in FIG. 2, it is not possible to form a winding distribution in which the horizontal deflection coil 2 and the vertical deflection coil 3 intersect as shown in FIG. 3.

[Purpose of the invention]

The present invention has been made in order to eliminate the drawbacks of the prior art as described above, and the objects of the present invention are to provide a device with a small eddy current product, good horizontal deflection sensitivity, and easy assembly.
Another object of the present invention is to provide a deflection yoke with a high degree of freedom in setting the winding distribution.

[Summary of the invention]

In order to achieve the above object, the present invention makes the air gap length on the inner surface of the core of the deflection yoke shorter on the vertical axis than on the horizontal axis, and also arranges the bottom surfaces of the grooves provided on the inner surface of the core almost concentrically. The length of the protrusion is made shorter at a position where the angle is larger, and only the vertical deflection coil is buried in the groove on the inner surface of the core.

[Embodiments of the invention]

The present invention will now be described in detail with reference to the drawings.

FIGS. 4 and 5 are a perspective view and a sectional view showing a first embodiment of the present invention. In the deflection yoke shown in the figure, the air gap length lv on the vertical axis 8 on the inner surface of the core is shorter than the air gap length IH on the horizontal axis 9. As shown in FIG. 6, a groove 4a is provided on the inner surface of the core 4, and a vertical shaft 8
The grooves are formed shallower at positions where the angle θ is larger, and the bottoms 4c of the grooves 4a are arranged substantially concentrically. Only the vertical deflection coil 3 is wound in a toroidal manner around #4a, and the horizontal deflection coil 2 is provided inside the core 4 with a separator 5 in between.

In the deflection yoke 1 of the present invention, the air gap length IV on the vertical axis is short and the horizontal deflection coil 2 is not housed in the groove 4a of the core 4. Compared to this, only the magnetic field that contributes to horizontal deflection can be strengthened, and horizontal deflection sensitivity can be improved. Also,
Similar to the conventional deflection yoke shown in FIG. 2, the vertical deflection coil 3 is housed in the groove 4aJ of the core 4, and the magnetic flux of the horizontal deflection magnetic field 7 mainly passes through the protrusion 4b, and the vertical deflection coil 3 in the groove
Since the magnetic flux crossing the vertical deflection coil 3 is small, the eddy current 10 generated when the horizontal deflection magnetic field 7 crosses the vertical deflection coil 3 can be reduced as shown in FIG. This can be reduced compared to the deflection yoke shown in the figure. On the other hand, in the present invention, the horizontal deflection coil 2 is connected to the groove 4a of the core 4.
Unlike the conventional deflection yoke shown in Fig. 2, it is easy to assemble. It can be formed easily, and there is a large degree of freedom in setting the winding distribution. The toroidal vertical deflection coil 3 according to the present invention can be easily wound as in the conventional method by dividing the core 4 on the horizontal axis 9 as shown in FIG.

FIG. 9 is a front view of a deflection yoke, particularly a vertical deflection coil, showing a second embodiment of the present invention.

As shown in the figure, the vertical deflection coil 3 may be formed in a saddle shape.

〔Effect of the invention〕

The deflection yoke of the present invention is constructed as described above, by making the air gap length on the inner surface of the core shorter on the vertical axis than on the horizontal axis, and by embedding only the vertical deflection coil in the groove provided on the inner surface of the core. Strengthens only the magnetic field that contributes to horizontal deflection,
By weakening the magnetic field that crosses the vertical deflection coil, the horizontal deflection sensitivity is improved and the eddy current product in the vertical deflection coil is reduced.The horizontal deflection coil is separated from the core and installed inside the core, making assembly easy. Thus, a deflection yoke with a high degree of freedom in setting the winding distribution of the deflection coil can be obtained.

[Brief explanation of the drawing]

1(a) and 1(b) are diagrams showing a conventional semi-toroidal deflection yoke. FIG. 1(a) is a perspective view, FIG. 1(a) is a sectional view, and FIG. ) and FIG. 2(b) are diagrams showing a conventional saddle-saddle type deflection yoke. FIG. 2(a) is a perspective view, FIG. 2(b) is a sectional view, and FIG. 3 is a winding of a deflection coil. 4 is a perspective view of the semi-toroidal deflection yoke according to the present invention, FIG. 5 is a sectional view of the deflection yoke of the present invention, FIG. 6 is a perspective view of the core, and FIG. 7 is a perspective view of the deflection yoke of the present invention. Front view showing the half-rest of the vertical deflection coil shown in Fig. 8.
The figure is a perspective view of a main part for explaining eddy current, and FIG. 9 is a front view of a saddle-shaped vertical deflection coil according to another embodiment of the present invention. Explanation of symbols 1... Deflection yoke 2... Horizontal deflection coil 3.
- Vertical deflection coil 4...Core 4a...Groove on the inner surface of the core 4b...Protrusion 4c on the inner surface of the core...Bottom surface of the groove in the core 5...Separator 6...Clip 7.7a,
7b...Horizontal deflection magnetic field 8...Vertical axis 9...Horizontal axis 10...Eddy current

Claims (1)

[Claims] In the deflection yoke attached to the cathode ray tube,
The core used in the deflection yoke has an inner surface formed such that the air gap length on the vertical axis is shorter than the air gap length on the horizontal axis, and a plurality of pairs of grooves and protrusions are formed on the inner surface of the core. In addition, the depth of the groove is shallower at a position where the angle with the vertical axis is larger, and the bottom surfaces of the grooves are arranged on a substantially concentric circle, and a vertical deflection coil is buried in this groove, and a horizontal deflection coil is embedded in the core. A deflection yoke characterized by being arranged inside the protrusion.