JP3067488B2 - Deflection yoke device for color picture tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color television receiver, C
The present invention relates to a deflection yoke device for a color picture tube used for an RT display device or the like.

[0002]

2. Description of the Related Art FIGS. 4 and 5 show a deflection yoke device for a color picture tube according to the prior art, and FIGS.

In the drawing, reference numeral 1 denotes a deflection yoke device for a color picture tube according to the prior art. The deflection yoke device 1a for a color picture tube is formed by expanding the diameter of a resin material in a bosh shape, and has a front end enlarged portion 2A and a rear end. A coil bobbin 2 having an enlarged portion 2B, a core 3 provided on an outer peripheral side of the coil bobbin 2, a pair of horizontal deflection coils 4, 4 provided on an inner peripheral side of the coil bobbin 2, and a coil wound around or inside the core 3; Vertical deflection coil 5 provided at the front end enlarged portion 2A
It is substantially constituted by a geomagnetic correction coil 12 provided in the vicinity thereof so as to be wound on a plane perpendicular to the tube axis of the picture tube 6. The deflection yoke device 1a is attached to the neck portion 6A of the color picture tube.

In the prior art having such a configuration, an electron beam 9 is emitted from three color electron guns (not shown) provided at the neck 6A of the color picture tube 6. The electron beam 9 is deflected by the horizontal deflection coil 4 and the vertical deflection coil 5, passes through a shadow mask (not shown) provided inside the color picture tube 6, and approaches the screen 6 B of the color picture tube 6. Each of the electron beams 9 is applied to the red, green, and blue phosphor dots 8 provided on the phosphor screen 6C.
Is to hit.

In such a color picture tube device, the screen 6B of the color picture tube 6 faces east during adjustment as shown in FIG.
The upper raster pattern 10 (hereinafter referred to as raster) becomes a normal screen 6B without rotation and vertical movement. However, when the screen 6B is turned north from this state, the geomagnetism acting from left to right in the drawing when facing east disappears, and the color cathode ray tube 6 newly acts from the neck side to the face side. This change in terrestrial magnetism affects the electron beam 9, causing the electron beam 9 to shift upward and twist counterclockwise. This allows the color picture tube 6
The raster 10 on the drawing 6B moves from X, Y in the direction of X ', Y' as shown in FIG.

Conversely, when the screen 6B is turned to the south, the terrestrial magnetism from left to right in the drawing disappears as in the case of the north direction, and the face of the color picture tube 6 goes from the face side to the neck side in the opposite direction to the north direction. Geomagnetism is added. This causes the electron beam 9 to move upward and rotate clockwise.

FIGS. 9, 10 and 11 are enlarged views of one-dot trios of the upper left a, b and c of the screen 6B of FIGS. 6, 7 and 8, respectively. In the east direction shown in FIG. 9, as described above, each electron beam 9 accurately strikes the dot 8 of each phosphor. On the other hand, in the north direction as shown in FIG. 10, the geomagnetism acting from the left to the right in the drawing disappears, and the geomagnetism from the neck side of the color picture tube 6 toward the fence side newly acts, The electron beam 9 moves right upward and shifts in the lower left direction, and the electron beam 9 shifts in the lower left direction as a whole, so that a landing error occurs.

As shown in FIG. 11, in the south direction, the terrestrial magnetism from the left to the right in the drawing disappears and the terrestrial magnetism from the face side to the neck side of the color picture tube 6 is further applied. As a result, the electron beam 9 moves right above and at the same time moves to the upper right and is largely shifted to the upper right as a whole.

As described above, the color picture tube 6 passes the electron beam 9 through the shadow mask and reflects it on the fluorescent screen 6C. However, the movement of the raster 10 is affected by the influence of geomagnetism when the color picture tube device rotates in the direction. At the same time, the electron beam 9 moves,
There is a problem that the phosphor dots 8 do not accurately hit the phosphor dots 8, the whole of the phosphor dots 8 does not emit light, and color smudges appear. In a conventional method (Japanese Utility Model Laid-Open No. 3-37743) proposed to solve the above-described problem, as shown in FIG.
A correction coil 12 for generating a magnetic field for canceling this is mounted near the coil bibon 2A or 2B of the deflection yoke device 1a so as to be wound around the correction coil coil bobbin 11a around the tube axis of the color picture tube 6.
This correction coil is wound around the correction coil coil bobbin 11 for several turns as shown in FIG.
3. DC power supply 14 and variable resistor 15 are connected in series.

When the color picture tube apparatus faces north, current is supplied in the direction of FIG. 5A to generate a magnetic field in the direction B, thereby canceling the terrestrial magnetism from the neck side to the face side. As shown in FIG. 14, it is possible to reduce or eliminate the rotation of the raster 10 excluding the vertical movement and the rotation excluding the vertical displacement of the landing.

On the other hand, when facing south, a current flows in the direction of FIG. 5C to generate a magnetic field in the direction D, canceling the terrestrial magnetism from the face side to the neck side.
As shown in FIG. 15, the rotation of the raster 10 excluding the vertical movement and the rotation deviation of the landing excluding the vertical deviation of the landing can be reduced or eliminated.

However, as described above, the vertical movement of the raster 10 and the vertical movement of the landing due to the disappearance of the terrestrial magnetism from the left to the right in the drawing cannot be corrected.

[0013]

As described above, in the prior art, the magnetic field in the tube axis direction can be canceled, but the magnetic field in the horizontal direction cannot be corrected, so that X 'to X' as shown in FIGS. Displacement of raster 10 in the upward direction,
An upward landing deviation as shown in FIGS. 14 and 15 remains.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a deflection yoke device for a color picture tube having a function of simultaneously correcting a magnetic field in a horizontal direction as well as a magnetic field in a tube axis direction.

[0015]

In order to solve the above-mentioned problems, a deflection yoke device according to the present invention comprises a correction coil bobbin which is fitted around the tube axis of a color picture tube at the front end or the rear end of a coil bobbin. And a pair of correction coils having a predetermined angle in the horizontal direction with respect to a plane perpendicular to the tube axis of the picture tube, and wound around the correction coil bobbin.

[0016]

With the above arrangement, a corrected predetermined DC current is supplied to cancel the geomagnetism generated in the direction of the tube axis of the color picture tube, and to generate a magnetic field from left to right toward the tube surface. In the direction and the south direction, the same magnetic field state as the east direction or the magnetic field state very close to the east direction is maintained,
Raster movement and landing movement due to a change in geomagnetism can be eliminated or reduced.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a plan view of a deflection yoke device for a color picture tube according to the present invention. In this embodiment, the same components as those of the prior art shown in FIGS.
The same reference numerals are given and the description thereof will be omitted. 1
Reference numeral 1 denotes a coil bobbin for a correction coil for winding the correction coils 12A and 12B.
1 is fixed to the outer periphery of the front end enlarged portion 2A of the coil bobbin 2 using an adhesive or the like.

Reference numerals 12A and 12B denote correction coils for generating a correction magnetic field for correcting terrestrial magnetism.
A, 12B are respectively several times annularly correction coil bobbin 11 are wound at an angle in the horizontal direction theta _A, theta _B with respect to a plane perpendicular to each tube axis.

Each of the correction coils 12A, 12A
B is an inverting switch 1 similar to that shown in FIG.
3, a DC power supply 14, and a variable resistor 15 are respectively arranged in series.

In this embodiment, as shown in FIG. 7, when the screen 6B facing east is turned north, there is no terrestrial magnetism from left to right in the drawing with respect to the screen 6B. When the terrestrial magnetism is applied from the neck side to the face direction, the raster 10 and the landing change as shown in FIGS. 7 and 10. At this time, a magnetic field opposite to the terrestrial magnetism in the tube axis direction is generated in the correction coil 12A. By passing the DC current in this manner, the geomagnetism in the tube axis direction is canceled out, and a magnetic field is generated from the left to the right toward the screen 6, so that the magnetic field state is close to the east direction. FIG. 2 and FIG. 3 are explanatory diagrams of the state of the magnetic field when the screen faces north and south, respectively. Here, assuming that the terrestrial magnetism in the direction of the tube axis in the north direction is B _N , and the intensity of the magnetic field generated when a DC current is applied to the correction coil 12A is B _A , each correction coil 1
2A, if the mounting angle of the 12B is Θ _A = Θ _B = Θ, the variable shown in Figure 5 as described above, to generate a strength _{B A} of the magnetic field so that _B A _{cosΘ + B} N = 0 in FIG. 2 by adjusting the current value in the resistor 15, it is possible to cancel the geomagnetic B _N in the tube axis direction, it is possible to generate a magnetic field B _a sin? towards the right in addition then left on the screen 6.

Further, when the correction coil 12B is also energized, the terrestrial magnetism when eastward is B _E , and the intensity of the magnetic field generated in the correction coil 12B is B _B , B _A cosΘ + B _B cosΘ + B _N = 0 B _A sinΘ If the respective variable resistors 15 of the correction coils 12A and 12B adjust the magnetic field strengths B _A and B _B so that −B _B sinΘ = _BE , the same magnetic field as in the eastward direction can be obtained. The state can be obtained and the movement of the raster 10 and the landing does not occur, and the same normal raster 10 as shown in FIGS.
And landing.

Conversely, when the screen 6 is directed southward, if a DC current is applied to the correction coil 12B so that a magnetic field in a direction opposite to the terrestrial magnetism is generated, the terrestrial magnetism in the tube axis direction is canceled and the screen 6 is displayed. A magnetic field is generated from left to right toward the east, and the magnetic field state becomes closer to the east. When the geomagnetism facing south and B _S, by adjusting the variable resistor 15 shown in FIG. 5 so as to generate a _B B cosΘ + B S ₌ 0 and becomes such a magnetic field strength B _B as shown in FIG. 3, It is possible to cancel the geomagnetism B _S in the tube axis direction and generate a magnetic field B _B sin Θ going left to right toward the screen.

Furthermore when also energizing the correction coils _{12A, B B cosΘ + B A} cosΘ + B S = 0 B B sinΘ-B A sinΘ = B E become such magnetic field strength _B B, correction coils such that _{B A} 12B, by adjusting the respective variable resistors 15 12A can be obtained exactly the same magnetic field as when facing east, north can not occur the movement of the raster 10 and the landing as in the case of even facing south, 6 and 9
The correction can be made so that the landing is the same as the normal raster 10 shown in FIG.

As described above, each correction coil 12A,
By adjusting the amount of current by the inverting switch 13 and the variable resistor 15 of the 12B, the movement of the raster 10 and the landing can be corrected simultaneously and reliably, color blur can be prevented, and a high-quality color image can be reliably projected. And various other effects.

Although the strength of the terrestrial magnetism varies depending on the location, it can be used in any location by adjusting the amount of current with the variable resistor 15.

In this embodiment, the correction coil coil bobbin 11 and the correction coils 12A and 12B are provided on the outer periphery of the front end enlarged portion 2A of the coil bobbin 2. However, the fixing position of the correction coil coil bobbin 11 is changed to the front end enlarged of the coil bobbin 2. It may be provided on the front end surface or the rear end surface of the portion 2A, or may be provided on the inner peripheral surface of the front end enlarged portion 2A.

On the other hand , the correction coils 12A and 12B can be provided in the enlarged rear end portion 2B of the coil bobbin 2. However, in this case, the spot of the electron beam 9 and the correction coil 12
Since the distance between A and 12B is long, the correction efficiency is slightly reduced.

In this embodiment, a pair of correction coils 12
A and 12 are provided at the same angle に 対 し て with respect to the horizontal tube axis direction, and the respective angles Θ _A and _{Ｂ B} are larger than 0 ° and 9
If it is less than 0 °, a different value may be used.

Further, it is also possible it takes more setting the correction coils, if one or more pairs provided need not necessarily be paired for that additional amount. It can also be provided together with a conventional correction coil provided perpendicular to the tube axis.

[0031]

As described above in detail, according to the present invention, a pair of correction coils that are not parallel to the tube axis are provided at the front end or the rear end of the coil bobbin, and a direct current is applied to the coil to correct the change in the geomagnetism. The magnetic field can be canceled and the same magnetic field state as the east direction can be always maintained. As a result, the movement of the raster and the landing due to the change in the geomagnetism can be simultaneously and reliably prevented, and a high-quality color image can be displayed.

[Brief description of the drawings]

FIG. 1 is a plan view of a deflection yoke device for a color picture tube according to the present invention.

FIG. 2 is an explanatory diagram of a magnetic field when correction is performed by a correction coil in a north direction according to the present invention.

FIG. 3 is an explanatory diagram of a magnetic field when correction by a correction coil is performed in a south direction in the present invention.

FIG. 4 is a plan view of a deflection yoke device for a color picture tube according to the related art.

FIG. 5 is a circuit diagram including a correction coil of the deflection yoke device for a color picture tube.

FIG. 6 is an explanatory diagram of a screen showing a normal state of a raster.

FIG. 7 is an explanatory diagram of a screen showing a raster state when the screen is facing north;

FIG. 8 is an explanatory diagram of a screen showing a raster state when the screen is facing south;

FIG. 9 is an enlarged explanatory view showing a state of a phosphor dot and a landing in a portion a of FIG. 6;

FIG. 10 is an enlarged explanatory view showing a state of a phosphor dot and a landing in a portion b of FIG. 7;

FIG. 11 is an enlarged explanatory view showing a state of a phosphor dot and a landing at a portion c in FIG. 8;

Figure 12 is an explanatory diagram of a screen showing the status of the raster when performing correction by our Keru correction coil in the prior art with respect to FIG.

Figure 13 is an explanatory diagram of a screen showing the status of the raster when performing correction by our Keru correction coil in the prior art with respect to FIG.

FIG. 14 is an explanatory diagram showing a state of a phosphor dot and a landing at a portion d in FIG. 12;

FIG. 15 is an explanatory view showing a state of a phosphor dot and a landing in an e part of FIG. 13;

[Explanation of symbols]

 Reference Signs List 1 deflection yoke device for color picture tube 2 coil bobbin 3 core 4 horizontal deflection coil 5 vertical deflection coil 6 color picture tube 6A color picture tube neck 6B color picture tube face screen 6C color picture tube fluorescent screen 8 phosphor dot 9 electron beam 10 raster 11 Coil bobbin for correction coil 12A, 12B Correction coil 13 Reverse switch 14 DC power supply 15 Variable resistor

Claims (3)

(57) [Claims] 1. A coil bobbin comprising a coil bobbin, a core provided on the coil bobbin, a horizontal deflection coil and a vertical deflection coil provided along the coil, wherein the coil bobbin is mounted on a neck portion of a color picture tube. In the deflection yoke device for a color picture tube, a bobbin for a correction coil fitted around the tube axis of the picture tube is provided in the vicinity of the opening at the front end or the rear end side of the coil bobbin, and the horizontal component of the terrestrial magnetism and the tube axis direction effect in the horizontal direction with respect to a plane perpendicular to the tube axis of the picture tube for correcting, greater than 0 °, 9
A deflection yoke device for a color picture tube, wherein a pair of correction coils arranged in a direction intersecting each other at an angle of less than 0 ° are wound around the correction coil bobbin. 2. A method according to claim 1 Symbol, characterized in that provided above the pair to the correction coil by the same correction coil in the coil bobbin
Onboard deflection yoke device. 3. The deflection yoke device for a color picture tube according to claim 1, wherein the mounting angles of said pair of correction coils are the same.