JPH1040832A - Linearity coil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To select DC multiplexing characteristic, matching the wide range of frequency by mounting plural circuits and to correct the distortion of a screen with high precision. SOLUTION: In a linearity coil 10, a drum core 16 on which coils 18 are wound is encircled by a ring magnet 14 with the inner face magnetized to N, S-poles to form a closed magnetic path with the drum core 16 and the ring magnet 14. Plural coils 18 may be wound on the drum core 16. Plural coils 18 may be wound on the drum core 16 separately at different positions, in plural layers or at the same time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linearity coil used for a circuit for correcting horizontal deflection distortion of a monitor such as a television receiver and a personal computer.

[0002]

2. Description of the Related Art Linearity coils are used, for example, to correct horizontal distortion of a television receiver or a monitor of a personal computer. In a TV, the frequency of the current flowing through the linearity coil is 15.7
Since the frequency is fixed at 5 kHz or 33.75 kHz, distortion can be corrected with a fixed linearity coil.

[0003] However, in a monitor of a personal computer, the range of the applied current frequency is f = 15 kHz to 120 kHz, so that the correction amount differs between when the frequency is low and when it is high.

Therefore, two linearity coils are used, and the amount of correction is adjusted by switching a relay or the like.
Such a problem has been solved by applying a DC current to one coil of a linearity coil having a structure in which two coils are connected in series and adjusting the characteristics of the other coil.

FIG. 4 is a sectional view showing an example of the latter linearity coil. In FIG. 1, reference numeral 12 denotes a pedestal. Two drum cores 16 and 16 and a permanent magnet 24 are mounted on the pedestal 12 in series upward, and a coil 18 is wound around the drum cores 16 and 16, respectively. ing.

A plurality of lead terminals 22 are implanted downward on the lower surface of the pedestal 12, and each end of the coil 18 wound around the drum core 16 passes through the pedestal 12 and is entangled with the lead terminal 22. And fixed by solder.

[0007]

The above-mentioned linearity coil has the following problems. Since the two drum cores and the permanent magnet are connected in series, the height dimension of the linearity coil is increased. It is difficult to assemble the permanent magnet, the first coil, and the second coil. Due to its height dimension, it is unstable when mounted on a board. The large height affects other parts (especially cathode ray tubes). A wider frequency range requires a plurality of linearity coils, and a variable frequency range requires a wider adjustment range. Since the magnetic leakage from the permanent magnet at the upper end of the drum core is extremely large and adversely affects the peripheral part, a shield plate is required so as not to affect other parts, and thus the cost is high.

An object of the present invention is to provide a linearity coil which does not cause the above-mentioned problems.

[0009]

According to the present invention, in order to solve the above-mentioned problems, a drum core on which a coil is wound is surrounded by a ring magnet whose inner surface is magnetized to N and S, and the drum core and the ring magnet are surrounded by a ring magnet. And a plurality of coils were wound around the drum core in a linearity coil in which a closed magnetic circuit was formed.

Here, the plurality of coils may be separately wound around the drum core at different locations, may be wound around the drum core in a plurality of layers, or may be wound around the drum core simultaneously. You may. When the plurality of coils are separately wound around the drum core at different locations, each coil may be separated by a flange. When a plurality of coils are wound in a plurality of layers, an insulating tape may be interposed between the layers.

[0011]

[Function] A plurality of circuits are created and used depending on the frequency range. One of the plurality of circuits is used for adjusting a magnetic field or used as a distortion correction circuit. An adjustment current is applied to the first coil, and the magnetic field acting on the linearity coil is adjusted so as to be in the same or opposite direction as the polarity of the ring magnet. Further, the ring magnet has less leakage magnetism than the permanent magnet used in the conventional linearity coil, and hardly affects peripheral components.

[0012]

FIG. 1 is a sectional view of a linearity coil according to a first embodiment of the present invention. In FIG. 1, a linearity coil 10 includes a pedestal 12 and a ring magnet 1 mounted above the pedestal 12.
4, a drum core 16 coaxially inserted into the ring magnet 14, and three coils 18 wound around the drum core 16.

The ring magnet 14 is formed of a cylindrical permanent magnet whose inner surface is magnetized to N and S, and one end of the ring magnet 14 is fixed to the base 12 with an adhesive. The drum core 16 is made of a soft magnetic material having flange portions 16b, 16b at both ends of a rod-shaped core portion 16a. Drum core 16 has 3
The coils 18 are wound in layers, and an insulating tape 20 is interposed between the layers.

A pin-shaped lead terminal 22 is implanted downward on the lower surface of the pedestal 12, and each of the three coils 18 is connected to the lead terminal 22 in a state where the respective ends are tangled. It is fixed with solder.

FIG. 2 is a sectional view of a linearity coil according to a second embodiment of the present invention. In this linearity coil, three coils 18 are wound around a drum core 16 in three upper and lower stages. Each coil 18 is partitioned by a flange portion 16b. Other configurations are the same as those of the first embodiment.

FIG. 3 is a sectional view of a linearity coil according to a third embodiment of the present invention. In the linearity coil, three coils 18 are wound around the drum core 16 at the same time. In this case, since the three coils 18 are wound simultaneously, the insulating tape 20 is not used. Other configurations are the same as those of the first embodiment.

[0017]

According to the present invention, when a plurality of coils are wound around one linearity coil, there is an effect that the height need not be increased.

Further, according to the present invention, since a plurality of circuits are provided, a DC superimposition characteristic suitable for a wide range of frequencies can be selected, and therefore, there is an effect that a screen distortion can be corrected with high accuracy.

Further, according to the present invention, since the influence of the magnetic field is small, there is an effect that the color shift of the screen is reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view of a linearity coil according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a linearity coil according to a second embodiment of the present invention.

FIG. 3 is a sectional view of a linearity coil according to a third embodiment of the present invention.

FIG. 4 is a sectional view of an example of a conventional linearity coil.

[Explanation of symbols]

 10 Linearity coil 12 Pedestal 14 Ring magnet 16 Drum core 16a Core 16b Flange 18 Coil 20 Insulating tape 22 Lead terminal 24 Permanent magnet

Claims (4)

[Claims] 1. A linearity coil in which a drum core around which a coil is wound is surrounded by a ring magnet whose inner surface is magnetized to N and S, and a closed magnetic path is formed by the drum core and the ring magnet. A linearity coil characterized in that a plurality of coils are wound around the coil. 2. The method according to claim 1, wherein the plurality of coils are separately wound around the drum core at different locations.
Linearity coil described in. 3. The linearity coil according to claim 1, wherein the plurality of coils are wound around the drum core in a plurality of layers. 4. The linearity coil according to claim 1, wherein the plurality of coils are simultaneously wound around the drum core.