JP3038815B2 - Deflection coil - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a deflection coil of a cathode ray tube.

[Summary of the Invention] A deflection coil according to the present invention includes first and second coil portions of a deflection coil for generating a predetermined deflection magnetic field for deflecting a beam to both sides as viewed from the tube axis of a picture tube. When the area is defined as an area, the deflecting coil is provided over the first area and the second area.
A winding main winding coil and the first region or the second
And the winding direction of the main winding coil and the auxiliary winding coil, and the winding of the transition portion from the first region to the second region. By configuring the winding direction of the wire to be the same direction, it is possible to obtain a magnetic field distribution that cannot be obtained by ordinary coil winding. It is configured such that the windings can be formed in the same direction.

[Related Art] A deflection yoke in a cathode ray tube (CRT) includes a pair of vertical deflection coils and a pair of horizontal deflection coils. For example, the horizontal deflection coil is wound around a saddle-shaped bobbin, so that the coil is wound in a saddle shape as shown in FIG. Is determined by the distribution of the current flowing in the total cross section of. Note that the Z axis coincides with the beam optical axis. Further, when viewed in a plane with the X-axis and the Y-axis as references, the winding method of the coil is as shown in FIG.
It flows in the direction indicated by arrow i in the figure and in the opposite direction.

The coil cross section can be represented as shown in FIG. 6 based on the X axis and the Y axis.

Here, in the first quadrant (the right cross section of the coil) in FIG. 6, it is assumed that a current flows from the top of the paper to the direction passing through the paper, and the second quadrant (the left cross section of the coil).
On the contrary, it is assumed that a current is flowing in a direction from the back of the paper to the top of the paper.

At this time, the current distribution in the right-side cross section of the coil in FIG. 6 is as shown in FIG. 7, in which the vertical axis represents the current intensity I and the horizontal axis represents the angle θ with respect to the X axis.
Note that the current distribution on the left side section is represented symmetrically with FIG. 7 (the polarity is reversed).

By the way, it is generally known that the convergence characteristics can be improved by manipulating the magnetic field distribution of the deflection yoke, and it is necessary to reduce the amount of current in a predetermined portion by changing the shape of the coil or partially adjusting the number of windings. And so on. For example, if reducing the winding number of the parts of the theta _a through? _B in the coil current distribution as shown in FIG. 7, 8
A current distribution as shown in the figure can be obtained, and thus a magnetic field having a predetermined convergence characteristic can be obtained.

However, in a method of obtaining a predetermined magnetic field distribution by such a method, a state where a winding of a predetermined portion is set to zero is a limit. That is, this is the current distribution state in FIG. 9 when the winding between θ _a and θ _b is zero.

If it is desired to further increase the degree of freedom of setting the magnetic field distribution, for example, a coil is folded back and wound in the middle as shown in FIG. 10 to obtain, for example, _a current in the reverse direction only between θ _{a and} θ _b. In this way, it is theoretically possible to set a current (magnetic field) distribution state as shown in FIG. 11, for example.

[Problems to be Solved by the Invention] However, as shown in FIG. 10, it is difficult to manufacture a coil by winding it back at a certain portion, which is not practical.

Because, usually, a winding machine that winds a coil on a coil bobbin is designed to always perform a winding operation in a fixed direction. Must be done, resulting in unnecessary costs and time losses.

Therefore, conventionally, when actually trying to change the magnetic field distribution state between θ _a and θ _b , the state shown in FIG. 9 is the limit, and the degree of freedom in setting the magnetic field for convergence correction is small. There was a problem.

[Means for Solving the Problems] The present invention has been made in view of such problems, and has a predetermined configuration for deflecting a beam on both sides as viewed from a beam optical axis in a tube axis direction of a picture tube. Each of the coil portions for generating the deflection magnetic field of FIG.
When the first quadrant region and the second quadrant region in the figures and the like are the first and second regions, respectively, in each of the first and second regions, one round of the coil is completed only within that region. It is to provide a deflection coil in which a coil is wound so that a coil portion (auxiliary winding portion) is formed.

[Operation] For example, as shown in FIG. 1 as points A to B and points C to D, if an auxiliary winding portion in which one turn of the coil is completed only in one area is formed, the first area is formed. it can be from the conventional current direction i _F opposite current direction i _R when the second region one round toward is wound, obtained in each region.
Moreover, in this case, there is no need to reverse the coil winding direction and turn it back.

Embodiments FIGS. 2A to 2E are a plan view, a front view, a bottom view, a side view, and a rear view of a saddle-type horizontal deflection coil showing one embodiment of the deflection coil of the present invention. . The horizontal deflection coils are paired in two units and attached to the neck portion of the cathode ray tube together with a pair of vertical deflection coils, and are configured as a deflection yoke.

1 is a saddle-shaped coil bobbin, 2 to 18 are locking pieces formed symmetrically in front of the bobbin, 20 to
Reference numeral 28 denotes a locking piece formed symmetrically at the rear of the bobbin. Reference numeral 30 denotes a coil wound in a saddle shape by using the locking pieces 2 to 18 and 20 to 28 of the coil bobbin 1 as guides.

In the horizontal deflection coil of this embodiment, the first region and the second region
For example, as shown in FIG. 3, an auxiliary winding portion which can complete the one turn of the coil and adjust the magnetic field distribution is formed only in one of the regions, as shown in FIG. It is wound to be.

That is, when the auxiliary winding portion is individually viewed as a region on the right side of the drawing with the locking piece 2 as the center and a region on the left side in the drawing, in the area 1, from the point A through the locking piece 3
When the point is reached, one round in area 1 has been completed. Similarly, in the area 2, when the coil is wound from the point C to the point D via the locking piece 11, one round is completed only in the area 2. From point D onward, all windings are wound from region 2 to region 1 to complete one round.

With this winding, in each region, respectively to the main deflection current direction I _F, the current direction I _R opposite will occur. Therefore, as the current intensity distribution, for example, the one shown in FIG. 11 is obtained, that is, the degree of freedom in setting the magnetic field distribution is expanded. In addition, there is no need to reverse the winding direction and fold the portion including the portion crossing the intermediate portion between the first region and the second region.
Since the coil winding can always be completed by the winding operation in a fixed direction, the horizontal deflection coil of the present embodiment can be easily manufactured by a conventional winding machine.

In FIG. 3, the reverse current can be obtained only on the innermost peripheral side of each area. However, the portion to be made in the reverse direction and the number of windings thereof are set based on the magnetic field distribution required to be generated. In any case, it suffices if the circuit is designed so that one round is completed only within the area.

Needless to say, the present invention can be implemented as a vertical deflection coil.

[Effects of the Invention] As described above, in the deflection coil of the present invention, in the first and second regions, one round of the coil is completed only within that region, and the magnetic field distribution can be adjusted. By winding the coil so that the auxiliary winding part is formed,
There is an effect that a deflection coil having a portion where a current flows in a reverse direction, which has been difficult to manufacture conventionally, can be easily manufactured.

In addition, it is not necessary to reverse the winding direction including the portion that crosses the intermediate portion between the first region and the second region, and the winding can be completed by the winding operation in a fixed direction at all times. There is an advantage that it can be easily manufactured with a conventional winding machine.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a coil winding method of a deflection coil according to the present invention. 2 (a), (b), (c), (d), and (e) are a plan view, a front view, a bottom view, a side view, and a rear view of one embodiment of the present invention. FIG. 3 is an explanatory diagram of the coil winding method of the present embodiment. FIG. 4 is an explanatory view of an example of a saddle type horizontal deflection coil. FIG. 5 is an explanatory view of a normal coil winding method. FIG. 6 is a schematic diagram of a coil cross section. FIG. 7 is an explanatory diagram of a current distribution. FIG. 8 is an explanatory diagram in the case where the current distribution is changed by reducing the number of coil windings in a specific portion. FIG. 9 is an explanatory diagram in the case where the current distribution is changed without performing coil winding on a specific portion. FIG. 10 is an explanatory diagram in the case where the coil winding direction for obtaining a reverse current is turned back. FIG. 11 is an explanatory diagram when the current distribution is changed by the reverse current. 1 is a coil bobbin, 2 to 18, 20 to 28 are locking pieces, and 30 is a coil.

Claims (1)

(57) [Claims] 1. A deflection coil wound on both sides thereof around a tube axis of a saddle-type deflection coil as a first area and a second area, respectively, wherein the deflection coil is the first area. A main winding coil that makes one turn over the region and the second region, and an auxiliary winding coil that makes one turn only within the first region or the second region, and The deflection direction is configured such that the winding direction of the coil and the auxiliary winding coil and the winding direction of the winding of the transition portion from the first region to the second region are the same. coil.