JPH0487240A - Deflecting yoke - Google Patents

Abstract

PURPOSE:To correct mis-convergence or luster distortion by intruding a part of a coil wire, which is wound around a magnetic core to form a vertical or horizontal deflecting coil, into a stripe groove through a flat surface. CONSTITUTION:A magnetic core 8 that can be divided into two pieces in the axial direction, is formed into a funnel shape or a shape similar to a funnel, and is provided with numerous stripe grooves 9 formed radially on the inner circumferential surface and flat surfaces 11 not having any stripe groove 9. The flat surface 11 is continuous to the bottom portion of the stripe groove 9 in the vicinity of an axial end portion. A part of a coil wire wound around the magnetic core 8 for forming a vertical or horizontal deflecting coil is intruded into the stripe groove 9 through the flat surface 11. Accordingly, a winding distribution can be freely adjusted on the flat surface 11 so that a local magnetic field, which largely deforms a magnetic field distribution in at least one of a small diameter end side and a large diameter end side into a barrel shape or a pin cushion shape, can be adjusted. Therefore, it is possible to correct mis-convergence or luster distortion.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a deflection yoke that is attached to a cathode ray tube such as a picture tube and applies a deflection magnetic field to an electron beam.

BACKGROUND OF THE INVENTION Such a deflection yoke is usually constructed as shown in FIG. A pair of vertical deflection coils (not shown) are respectively wound around the magnetic core 3.

Incidentally, in recent years, in order to improve the image definition or display capability of display devices and TV receivers, the frequency of horizontal scanning has been set higher than conventional ones. However, in this case, the temperature of the deflection yoke is likely to rise, so consideration must be given to suppressing the temperature rise.When the horizontal scanning frequency is about 33KHz to 64KHz, the wire diameter of the horizontal deflection coil can be made small to reduce the wire load. Even if measures can be taken by increasing the ratio, using litz wires (stranded wires), or changing the material of the magnetic core, ultra-high-speed scanning equipment with a horizontal scanning frequency of 100 KHz or 128 KHz will not work as described above. It is not possible to suppress the temperature rise of the deflection yoke by taking appropriate measures alone.

In the deflection yoke disclosed in Japanese Unexamined Patent Publication No. 1-157037, etc., as shown in FIG. A part of the winding 5 forming the coil is inserted into the groove 4. In this case, the magnetic shielding effect of the magnetic core 3 works strongly (therefore, it is possible to reduce the Joule heat loss caused by the eddy current caused by the horizontal deflection magnetic field flowing into the vertical deflection coil, and to alleviate the temperature rise of the deflection yoke.

The vertical deflection coil shown is a saddle type, so
A semicircular plate 6 made of synthetic resin is attached to the large-diameter end surface of the magnetic core 3, and a portion of the winding 5 is caught or bridged by a large number of claws 7 provided on the plate 6. Although not shown, a semicircular plate similar to the plate 6 is also provided on the small diameter end surface of the magnetic core 3. In addition, the illustrated magnetic core 3 is 1
Only one of the pair, which is funneled together with the other during implementation.

Problems to be Solved by the Invention By the way, a large number of grooves 4 provided on the inner circumferential surface of the magnetic core 3 run radially at approximately equal intervals, and there are partition walls between each groove 4, so that vertical deflection is prevented. Changing the winding distribution of the coil near the end in the axial direction, that is, on the small diameter end side (electron gun m
) to strongly distort the vertical deflection magnetic field distribution into a barrel shape,
There was a drawback in that it was not possible to correct misconvergence or raster distortion of the child beam due to the vertical deflection magnetic field distribution on the large diameter end side (phosphor screen surface (Ipl) being distorted in a binction shape). .

Means for Solving the Problems According to the present invention, a funnel-shaped or similar cylindrical magnetic core configured to be able to be divided into two in the radial direction has a large number of grooves running radially on its inner surface; A smooth surface having no such grooves. The smooth surface is located near the axial end and communicates with the bottom of the groove, and a portion of the winding that is wound around the magnetic core to form a vertical deflection coil or a horizontal deflection coil passes through the smooth surface. It is configured to fit into the groove.

Effect: With this configuration, although the magnetic core has a configuration in which a large number of grooves run radially on the inner peripheral surface, the winding distribution of the winding portion on the way from one groove to the next groove can be smoothed. Since it can be freely adjusted on the surface, it is possible to locally adjust the magnetic field such that the magnetic field distribution on at least one of the small diameter IS and large diameter ends is strongly distorted in a barrel shape or in a bincussion shape.

Embodiments Next, the present invention will be explained along with embodiments shown in the drawings.

The magnetic core 8 shown in FIG. 1 is divided into two parts in the radial direction, and forms a funnel-shaped magnetic core together with the other magnetic core (not shown). On the inner peripheral surface of this magnetic core 8 made of ferrite, a large number of grooves 9 running radially are provided at approximately equal intervals. however,
The groove 9 and the convex partition wall 10 formed thereby are adjacent to a recess 11 provided near the small diameter end. recess 11
is a substantially smooth surface that communicates with the bottom of the groove 9 without any difference in level. Furthermore, a semi-circular plate 6 made of synthetic resin having a large number of claws 7 is attached to the large-diameter end surface of the magnetic core 8 by adhesive. A plate is also attached on the small diameter end face of the magnetic core 8.

A part of the winding 5 that is saddle-wound around the magnetic core 8 to form a vertical deflection coil enters the groove 9, and the part of the winding that comes out from the groove 9 is exposed to the magnetic field on the small diameter end side. In order to adjust the distribution, it is wound unevenly within the recess 11 and transferred to the adjacent groove.

The magnetic cores 8 wound with the vertical deflection coils are combined in a symmetrical funnel shape, and are disposed on the outer peripheral surface of the insulating cylinder as shown in FIG. A deflection yoke is formed together with a pair of horizontal deflection coils provided on the inner peripheral surface of this insulating cylinder.

In the embodiment described above, the recess 11 was provided near the small diameter end, but in the embodiment shown in FIG. 2, the recess 12 with a smooth surface was provided near the large diameter end. Further, in the embodiment shown in FIG. 3, a recess 11 is provided near the small diameter end, and a recess 12 is provided near the large diameter end.

In either case, although the position occupied by the winding 5 is restricted by the grooves 9 and the partition wall 10, the recess 11 has a smooth surface.
The winding portion within the coil is not subject to such restrictions. Therefore, the winding distribution within the recess 11 can be set relatively freely, and by distorting the magnetic field distribution on the small diameter end side or the large diameter end side into a strong barrel shape or a bink tension shape, It becomes possible to correct misconvergence and raster distortion.

Effects of the Invention As described above, according to the present invention, the inner circumferential surface of the magnetic core is provided with a large number of grooves to alleviate temperature rise, and the density distribution of the winding wire near the axial end of the magnetic core is reduced. Therefore, it has the advantage of being able to arbitrarily adjust the magnetic field distribution, and is particularly effective when applied to deflection yokes for high-definition color picture tubes.

[Brief explanation of the drawing]

1, 2, and 3 are perspective views of main parts of a deflection yoke embodying the present invention, FIG. 4 is a side sectional view of a conventional deflection yoke, and FIG. 5 is a conventional magnetic core and its FIG. 4 is a perspective view showing the relationship between the vertical deflection coil and the saddle-wound vertical deflection coil. 5... Winding wire, 8... Magnetic core, 9
...grooves, 11.12 ... recesses. Name of agent: Patent attorney Shigetaka Awano 1 idiot Figure 4

Claims (1)

[Claims] A funnel-shaped or similar cylindrical magnetic core configured to be able to be divided into two in the radial direction has a large number of grooves running radially on its inner peripheral surface and a smooth surface having no such grooves. , the smooth surface is located near the axial end and communicates with the bottom of the groove, and a portion of the winding that is wound around the magnetic core to form a vertical deflection coil or a horizontal deflection coil is connected to the smooth surface. A deflection yoke, characterized in that the deflection yoke enters the groove through the groove.