JPH0210543B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a deflection yoke mounted on a cathode ray tube of a television receiver or the like.

A known deflection yoke used in conventional television receivers is one in which a coil 2 is formed by winding a wire in a toroidal shape around a substantially cylindrical or wrapper-shaped core 1, as shown in FIG. The coil 2 is formed as a pair or a plurality of substantially symmetrical pairs with substantially the same winding specifications such as the number of turns and wire diameter. In addition, the respective coils 2 are connected in series (or in parallel) as shown in Fig. 2 so that substantially the same current flows, and a substantially symmetrical magnetic field distribution as shown in Fig. 3 is formed. There is.

Such a conventional toroidal deflection yoke has the following drawbacks.

(1) Because one or more pairs of coils with a high degree of identity must be manufactured, special consideration is required for the winding device.

(2) For coils that require high impedance, that is, a large number of turns, multi-layer split winding is required to prevent ringing, etc., which increases manufacturing time.

etc.

The present invention has been made in view of the above-mentioned drawbacks, and it is intended to facilitate the manufacture of a deflection coil by forming a deflection magnetic field using an induced current by forming one of the coils into a closed circuit.

Hereinafter, this invention will be described as an example in FIGS. 4 and 5.
The diagram will be explained.

In Figure 5, 2 is the original winding specification and core 1
The first coil 3 is wound around the first coil 2, and the second coil 3 is formed so that its cross section is point symmetrical to that of the first coil 2.
The coil is formed with winding specifications such that the ratio of inductance to DC resistance is the same as that of the first coil 2. Further, as shown in FIG. 4, the pair of coils 2 and 3 connects the first coil 2 to the output end of the deflection circuit, and makes the second coil 3 a closed circuit.

Under such a configuration, a pair of coils 2 and 3
The relationship between them is the same as that of a core type transformer, and the AC impedance seen from the first coil 2 side is converted by the turns ratio of the coils 2 and 3, and becomes equivalent to the impedance when connected in series. In addition, due to the induced voltage caused by the first coil 2 in the second coil 3, i ₂ =N ₁ /N ₂ i ₁ i ₁ : Current flowing in the first coil 2 N ₂ : Current flowing in the first coil 2 Number of turns i ₂ : Current flowing through the second coil 3 N ₂ : Number of turns of the second coil 3, and a current having the inverse ratio of the turns ratio flows. Therefore, the magnetic field φ ₂ generated by the second coil 3 is: φ ₂ =K・N ₂・1 ₂ =K・N ₂・N ₁ /N ₂・i ₁ =K・N ₁・1 ₁ ≒φ ₁ , and it is possible to obtain a magnetic field quite close to the magnetic field φ ₁ generated by the first coil 2, regardless of the turns ratio of the pair of coils 2 and 3. For example, for a deflection yoke for a 14" color TV, compare the case where coils with the original winding specifications are manufactured and connected in series as shown in Figure 2, and the case where one coil is short-circuited as shown in Figure 4. As a result, the vertical amplitude due to the deflection yoke of the latter was about 98% of the former.In other words, even if the winding specifications of the second coil 3 were different from those of the first coil 2, the ratio of inductance to DC resistance could be maintained. If they are made the same, almost the same deflection magnetic field can be generated.As a result, if the second coil 3 is made of a thicker wire than the first coil 2, the second coil 3
It becomes possible to reduce the number of windings of the coil 3, and the manufacturing time can be shortened. for example,
The first coil 2 is manufactured to the original winding specification with the number of turns N using a wire with a diameter of D, and the second coil 3 is manufactured with a wire with a diameter of √2D and the number of turns is N/2. For example, it is possible to obtain a deflection yoke having almost the same deflection characteristics as the conventional one in which both the coils 2 and 3 have the same specifications.

This allows the number of turns to be halved when manufacturing the second coil 3, which is not only advantageous in shortening the winding time, but also reduces material costs by increasing the diameter of the wire used. It has the advantage of being cheaper. This advantage is expanded by reducing the number of turns to 1/3, 1/4, etc. In addition, by inserting a current adjustment element such as a variable resistor or variable inductance into the closed circuit of the second coil 3, it is possible to correct asymmetry, etc., and further adjust the coupling coefficient of the core 1. By doing so, linearity can also be corrected. Furthermore, if a DC component is superimposed on the first coil 2, it will not flow through the second coil 3, which is effective for correcting distortion and asymmetry.

In the above-mentioned embodiment, a pair of substantially point-symmetrical coils was explained as an example, but the present invention can be similarly applied to a deflection yoke composed of a plurality of pairs of even number of toroidal coils.

As described above, according to the present invention, a new degree of freedom can be given to the design and manufacture of the deflection yoke, and the practical value of the present invention is great.

[Brief explanation of drawings]

1 to 3 are schematic diagrams showing the structure of a conventional toroidal deflection yoke, and FIGS. 4 and 5 are schematic diagrams showing a deflection yoke according to an embodiment of the present invention. In the figure, 1 is the core, 2 is the first coil, and 3 is the second coil.
It is a coil of In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1 A cylindrical or wrapper-shaped core, a first coil wound toroidally around this core, and a first coil wound toroidally around the core so that its cross section is point symmetrical to that of the first coil, and an inductance. a second coil having the same direct current resistance ratio as the first coil; the first coil is connected to the output end of the deflection circuit, and the second coil is connected to the first coil as a closed circuit; A deflection yoke characterized by inducing a current flowing through the yoke to form a deflection magnetic field.