JPS6029162Y2 - deflection yoke - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a deflection yoke that is attached to a color picture tube that houses an in-line electron gun (a system in which three electron guns are arranged along a horizontal axis).

In a color picture tube device equipped with an in-line electron gun, the magnetic field generated by the vertical deflection coil is basically called the barrel magnetic field 1, and the magnetic field generated by the horizontal deflection coil is called the bottle cushion magnetic field 2, as shown in Figure 1. It is well known that a deflection yoke having a non-uniform magnetic field distribution is used.

Generally, such a method is called a self-convergence method and is widely practiced.

By the way, although a good convergence effect can be obtained with such a self-convergence method, raster distortion still occurs due to the difference in the curvature of the color picture tube screen and the deflection curvature of the electron beam, as shown in the left and right arrows in Figure 2. The portion indicated by 3 protrudes outward, and the left and right sides have a pincushion-shaped distortion 4.

Conventionally, in order to correct this pincushion distortion 4, a method of adding a left and right pincushion distortion correction circuit device that superimposes and corrects a signal whose amplitude changes in a rose-shaped pattern synchronized with the vertical deflection signal on the horizontal deflection signal has been adopted. It is being

However, such left and right pincushion distortion correction circuits are backwards in terms of resource saving, low cost, and circuit simplification, and improvements are desired.

As an example of this improvement, a deflection yoke that is self-concentrating and has little pincushion distortion has been proposed, as shown in Japanese Patent Laid-Open No. 54-47421.

Next, to explain this structure with reference to the figure, the inclination angles θ□, θ2 (however, θ□〉
By toroidally winding the vertical deflection coil 14 so as to form an angle θ2), the shape of the vertical deflection magnetic field is changed to reduce left and right pincushion distortion.

However, winding the vertical deflection coil in this manner has the disadvantage that extremely difficult techniques are required in the manufacturing process.

The present invention was devised in view of the various drawbacks of the conventional art described above, and the object thereof is to provide a deflection yoke that is easy to manufacture and is capable of highly effective correction of raster distortion. .

Next, one embodiment of the deflection yoke of the present invention will be described with reference to FIGS. 4 to 6.

That is, the horizontal deflection coil 31 consists of a pair of coils wound in multiple layers of enameled wire or the like and molded and hardened into a saddle shape.
It is bonded and fixed to the inner wall of the separator 32.

On the outer peripheral surface of this separator 32, a circular annular core 33 is provided.
A vertical deflection coil 34 in which an enameled wire is wound in a toroidal shape is disposed in the vertical deflection coil 34 and is bonded and fixed to the separator 32 with thermoplastic resin 36 or the like.

The magnetic member 35 for magnetic field distribution adjustment is provided inside, outside, or in a non-contact state of the separator 32 so as to satisfy the following conditions.

That is, when viewed in the tube axis direction, the electron gun side end edge 3 of the magnetic member 35
5b is between the electron gun side end edge of the vertical deflection coil 34 and the electron gun side end edge of the horizontal deflection coil 31, and the screen side end edge 35a is between the screen side edge of the vertical deflection coil 34 and the horizontal deflection coil 31. Located closer to the electron gun than the side edge,
The plate thickness of the member is 0.2 to 0.7M! The screen side edge portion 35a, which is made of a ferromagnetic material such as permalloy of about

The cylinder has a circumferential length of 1□=35 mm, and the electron gun side edge portion 35b is formed into a substantially convex shape with a circumferential length of 1°=15 mm and a circumferential length of 1°=15 mm.

That is, what is important about the shape of the magnetic member 35 is that the length 1 □ in the circumferential direction of the electron gun side edge 35b, with the vicinity of the electron gun side edge of the vertical deflection coil 34 as the boundary, is the screen side edge 35. The length in the circumferential direction of the arm was made larger than 1□.
These conditions of 1□>1□ need to be considered comprehensively with the border near the edge of the vertical deflection coil 34 on the electron gun side, and it is worth mentioning that the boundary in the tube axis direction is not clear. Nor.

Further, the dimensions of the magnetic member 35 mentioned above are 20 inches.
This is for a color picture tube with a 1mφ neck, and it goes without saying that completely different values will be applied to picture tubes of other sizes.

Next, the effects of arranging the magnetic member as described above will be explained.

That is, this embodiment uses a self-convergence system as disclosed in, for example, Japanese Patent Laid-Open No. 54-47421, and in order to eliminate figure distortion due to deflection, a so-called bin cushion is used especially on the screen side of the vertical deflection magnetic field. It is a magnetic field, and the electron gun side is a so-called barrel magnetic field, and overall it is necessary to be a barrel magnetic field.

For this reason, the screen-side edge portion 35a of the magnetic member 35 of this embodiment is located within the vertical deflection coil 34, and it has the great effect of converting the vertical deflection magnetic field in this vicinity into a barrel magnetic field, as disclosed in Japanese Patent Laid-Open No. 54-47421. Although it is almost the same as the case of the publication, the structure of this publication generates a strong barrel magnetic field and at the same time absorbs a large amount of magnetic flux, resulting in a significant deterioration in deflection efficiency.

In order to prevent this deflection efficiency from significantly deteriorating, it is necessary to increase the winding angle θ of the vertical deflection coil on the electron gun side (see FIG. 2), and it is necessary to wind the vertical deflection coil at a significant inclination.

However, the magnetic member 35 of this embodiment is the vertical deflection coil 3.
Since an electron gun side edge part 35b is provided in the circumferential direction beyond the electron gun side end face of No. 4, which is relatively short with respect to 35a, the leakage magnetic field of the vertical deflection magnetic field can be used more effectively;
Further, since the barrel magnetic field also occurs in this portion 35b, the barrel magnetic field has the effect of extending to the electron gun side.

Therefore, the winding angle of the vertical deflection coil does not need to be so large on the electron gun side.

Furthermore, since the winding angle θ is smaller than that of the conventional example, the winding angle θ2 on the screen side of the vertical deflection coil 34 can be relatively large, and θ and 02 are smaller, making manufacturing easier and reducing variations. I can do it.

To explain the above principle of operation, when the winding angle θ1 on the electron gun side is small and the barrel magnetic field formed by the magnetic member extends further toward the electron gun side than in the past, the left and right pattern distortion becomes small.

Therefore, if it is formed on the screen side, the bottle cushion magnetic field can be made relatively weak.

Therefore, the screen side winding angle θ2 can be set relatively large.

The reason why the magnetic member is made convex in this example is to take into account the absorption of magnetic flux by the magnetic member itself.The magnetic field is strong between the vertical and horizontal deflection coils, and the edge of the magnetic member on the electron gun side is Since the leakage magnetic field is weak, the space between the vertical and horizontal deflection coils is wide, and the one on the electron gun side is narrow.

Next, a modified example of the magnetic member will be explained with reference to FIGS. 7 and 8. The magnetic member 45 is 20 inch 2
In a color picture tube with a 9.1 mm diameter neck, the upper side of the screen side edge 45a, that is, the length in the circumferential direction d3 = 40T
Ir! By setting the length d of the lower side of the rL electron gun side edge portion 45b in the circumferential direction = 10rrvn and the height h = 30mm, the same effect as in the example could be obtained.

Next, another embodiment of the present invention will be described with reference to FIGS. 9 and 10, but the same reference numerals as in the previous embodiment indicate the same parts and a detailed explanation will not be given.

That is, in this embodiment, in order to further reduce the distortion of the left and right pincushion shapes shown in FIG. 1, part of the pair of vertical deflection coils 34 and A pair of magnetic field absorbers 37 are disposed so as to cover part of the core 33 between the vertical deflection coils 34.

The magnetic field absorber 37 is disposed at a position where the magnetic fields generated by the pair of vertical deflection coils 34 are mutually exclusive, where the magnetic field is strongest and where leakage magnetic fields can be efficiently picked up.

At both ends of each of the magnetic field absorbers 37, arm-shaped magnetic field leakage bodies 37a are formed that protrude from the corners of the screen of the color picture tube, ie, at positions corresponding to the diagonal axis.

Therefore, a magnetic field synchronized with the vertical deflection magnetic field is generated in the magnetic field leaking body 37a, and it is possible to correct the screen side of the vertical deflection magnetic field to the direction of the pincushion magnetic field.

By using the magnetic member 35 in such a deflection yoke, the screen side of the vertical deflection magnetic field can be corrected more towards the pincushion-shaped magnetic field direction, and the vertical deflection magnetic field on the electron gun side can be corrected more towards the barrel-shaped magnetic field direction. This is possible, and it is possible to further reduce raster distortion compared to the previous embodiment.

As described above, the deflection yoke of the present invention can efficiently correct the raster distortion of a color picture tube incorporating an in-line electron gun, and its industrial value is extremely large.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram showing a deflection magnetic field suitable for the self-convergence method of a color picture tube equipped with an in-line electron gun, Figure 2 is an explanatory diagram showing raster distortion due to the deflection magnetic field in Figure 1, and Figure 3 is 4 to 6 are diagrams showing an embodiment of the present invention, FIG. 4 is a partially cutaway side view, and FIG. 5 is a plan view of the magnetic member. 6 is a perspective view showing the processed state of the magnetic member in FIG. 5, FIGS. 7 and 8 are views showing modified examples of the magnetic member, and FIG. 7 is a plan view of the magnetic member, Figure 8 is a perspective view showing the processed state of the magnetic member in Figure 7, Figures 9 and 10.
The figures show other embodiments of the present invention; FIG. 9 is a partially cutaway side view, and FIG. 10 is a simplified front view of FIG. 9 viewed from the screen side. 13.33...Core, 14.34...
Vertical deflection coil, 31...Horizontal deflection coil, 3
5...Magnetic material, 37...Magnetic field absorber,
37a...Magnetic field leakage body.

Claims (1)

[Scope of utility model registration request] It is installed on the outer wall from the neck to the funnel of the color picture tube that houses the in-line electron gun, and is wound in a toroidal shape around the core and a pair of horizontal deflection coils that generate a pincushion-shaped deflection magnetic field.The overall shape is barrel-shaped. In a deflection yoke, the deflection yoke includes a pair of vertical deflection coils that generate a deflection magnetic field and at least a pair of magnetic members that emphasize the electron gun side magnetic field distribution of the barrel-shaped deflection magnetic field. The edge portion is located between the electron gun side edge portion of the vertical deflection coil, and the screen side edge portion is located closer to the electron gun side than the screen side edge portions of the vertical deflection coil and the horizontal deflection coil, and a deflection yoke characterized in that a circumferential width of a portion of the magnetic member that is inside the vertical deflection coil is wider than a circumferential width of a portion of the magnetic member that is outside the vertical deflection coil. .