JPH0337942A - convergence yoke - Google Patents

Abstract

PURPOSE:To perform desired convergence adjustment having no influence on convergence adjustment and neck shadow tolerance by connecting the damping circuits consisting of a resistor and the diodes which are connected to the resistor, to the right and left convergence coils separately and in a series. CONSTITUTION:When a magnetic flux generated at a horizontal deflection coil 8 is absorbed by the right and cores 11r, 11l of a convergence coil 10, electromotive force reversed to an H-pulse is going to be generated in a closed loop to be constituted between the convergence coils 121, 122 wound about the right and left cores 11r, 11l respectively and the respective damping circuits 141, 142. However, since the diodes 161, 162 are interposed reversely to the direction, into which electromotive force is going to flow, no electromotive force is generated. Accordingly, no magnetic field in the reverse direction due to a leak magnetic flux of a deflection yoke 6 is formed. Thereby, no surplus magnetic field is formed to the convergence yoke, no neck shadow tolerance is narrowed while being able to perform desired convergence adjustment.

Description

DETAILED DESCRIPTION OF THE INVENTION The convergence yoke of the present invention will be explained according to the following items.

A, I! Field of use in the tea industry B0 Overview of the invention C1 Prior art [Figs. 7 to 10] D1 Problems to be solved by the invention E9 Means for solving the problems F, Examples [Figs. 1 to 6] F-1, First embodiment [Figures 1 to 4] a, Picture tube [Figures 1 and 2] b, Deflection yoke [Figure 1, Figure 2] C, Convergence yoke [Figure 2] 1 to 3] 61 action [Fig. 4] F-2, second embodiment [Fig. 5] a. Convergence yoke [Fig. 5 b0 action F-3, third embodiment [Fig. [Fig. 6] a. Damping circuit [Fig. 6] 61 Effects of the invention G0 (A. Field of industrial application) The present invention relates to a novel convergence yoke. Specifically, in the convergence yoke of a picture tube equipped with three cathodes arranged in-line, the convergence coil has been improved to eliminate the dark and light stripes (so-called linking) that occur on the screen, as well as to improve convergence adjustment and The present invention aims to provide a new convergence yoke that does not affect neck shadow margin.

(B. Summary of the Invention) The convergence yoke of the present invention is capable of adjusting convergence and neck shadow by connecting damping circuits each consisting of a resistor and a diode connected in series to the left and right convergence coils in parallel. This makes it possible to prevent linking from occurring without affecting margins.

(C, Prior Art) [Figures 7 to 10] In a color receiver, there are three electron beams, but there is only one deflection yoke that deflects them, so the three electron beams are A so-called convergence adjustment is necessary to make the images coincide with each other.

In a picture tube with three cathodes arranged in-line, a convergence yoke is disposed behind the deflection yoke in horizontal raster scanning, and the electron beams emitted from cathodes other than the central cathode are Each is deflected so that it coincides with the electron beam emitted from the central cathode at the fluorescent surface.

FIG. 6 shows an example of such a conventional convergence yoke a.

In the figure, b and b are E-type cores, which are arranged behind a deflection yoke (not shown) so as to sandwich the neck C of the picture tube from the left and right. Note that b is the core on the right side when viewed from the front, and b2 is the core on the left side.

d, d, ... are convergence coils, convergence coil d1 is attached to the upper arm of right core bl, convergence coil d2 is attached to the lower arm of right core b, and convergence coil d3 is attached to the upper arm of left core b. To,
The convergence coils d4 are wound around the lower arms of the left core b2, and these convergence coils d,
When a current flows through d, ..., a magnetic field e%e is formed between the convergence coils dl and d2 of the right core b1 and between the convergence coils d3 and d4 of the left core b2, In addition, the directions of the magnetic fluxes of these magnetic fields are opposite in the vertical direction of the right magnetic field el and the left magnetic field e2.

Note that the four convergence coils d, d.

* are connected in series to the convergence circuit f.

R and G%B indicate electron beams emitted from three cathodes (not shown), which are arranged horizontally inline when viewed from the front.

When the electron beams R%G and B pass through the portion where the convergence yoke a is arranged, the electron beams R and B other than the electron beam G located at the center are formed within the neck portion C, respectively. The three electron beams R and G are deflected to the left or right by the magnetic field elxe2, and three electron beams R and G are generated at the fluorescent surface.

B is made to match.

By the way, since such a convergence yoke a is disposed behind the deflection yoke, the leakage magnetic fluxes g and g of the deflection yoke are absorbed by its cores b and b2, resulting in a waveform of the induced magnetic field within the convergence yoke a. Among them, the negative voltage part hb other than the H pulse h1 oscillates ($8
Note that the induced magnetic field waveform is the voltage waveform of the electromotive force generated in the search coil when the search coil is wound around the cores b and b. This vibrating portion hb makes the angular velocity of the deflection angle of each electron beam R, G, and B unstable,
The scanning speed on the screen is not constant, and areas where the scanning speed is fast appear pale and areas where the scanning speed is slow appear dark, resulting in linking.

Therefore, each convergence coil d I""' d a
It is conceivable to connect a resistor in parallel to each of the oscillating portions hb to absorb the vibration portion hb.

FIG. 9 shows such a convergence yoke i, in which resistors j+ to j4 are separately connected in parallel to each convergence coil d, to d4 of the convergence yoke a.

In such a convergence yoke 1, the vibration portion hb of the induced magnetic field waveform in the cores b3 and b2 due to leakage magnetic flux g and g of the deflection yoke is transferred to the convergence coils d1 to d.
The resistors j1 to j4 connected in parallel to the cores b1 and b2 absorb the vibration, and vibrations can be prevented from occurring in the waveforms of the induced magnetic fields in the cores b1 and b2 (see FIG. 10).

(D. Problem to be Solved by the Invention) However, in the convergence yoke i, each convergence coil d, d2, d3 or d4 and each resistor j1%J2, js separately connected in parallel thereto.
Alternatively, a closed loop will be formed between each core and j4, and the leakage magnetic flux g of the deflection yoke will be absorbed by the cores b, , b, and a reverse magnetic field k will be generated.

Since this reverse magnetic field is generated at a position closer to the electron gun than the kli deflection yoke, it has a large effect on the deflection of the electron beams R, G, and B. Even with a small magnetic force, the electron beams R, G, and B There is a problem in that it greatly deflects the image, causing misconvergence.

Furthermore, due to the generation of %k in the reverse magnetic field, the voltage level (H pulse h,) in the waveform of the induced magnetic field of the convergence yoke a decreases, resulting in a problem that the convergence yoke cannot be adjusted sufficiently.

Furthermore, if an unexpected deflection occurs from the front of the deflection yoke (on the electron gun side), the electron beams R, G, and B will hit the front end of the neck C of the picture tube, causing the left and right ends of the screen to be chipped. Therefore, there is a problem in that the allowable range (so-called neck shadow margin) in which the deflection yoke can be retreated from the position where it is in close contact with the picture tube becomes narrow.

(E. Means for Solving the Problems) In order to solve the above problems, the convergence yoke of the present invention is a convergence yoke of a picture tube equipped with three cathodes arranged in-line, which are arranged on the left and right sides. A convergence coil is connected in parallel with a resistor and a damping circuit made up of a diode connected in series with the resistor.

Therefore, according to the convergence yoke of the present invention, even if the core of the convergence yoke absorbs the leakage magnetic flux of the deflection yoke, the vibration in the induced magnetic field waveform is suppressed by the resistor connected in parallel to the convergence coil, and the vibration is suppressed by the resistor connected in parallel to the convergence coil. The connected diode can prevent the generation of a magnetic field that occurs when the core absorbs the leakage magnetic flux of the deflection yoke, so that no unnecessary magnetic field is formed in the convergence yoke, and the neck shadow margin is not narrowed. Convergence adjustment can be performed.

(F. Embodiment) [FIGS. 1 to 6] Details of the convergence yoke of the present invention will be described below in accordance with each embodiment shown in the accompanying drawings.

In each of the embodiments shown in the drawings, the convergence yoke of the present invention is applied to a convergence yoke of a so-called single electron gun three-electron beam type picture tube.

(F-1, first embodiment) [Figures 1 to 4] 1 to 4 show a first embodiment.

(a, picture tube) [Figures 1 and 2] 1 is a picture tube, 2 is a funnel part of the picture tube 1, and 3 is formed so as to protrude rearward from the back surface of the funnel part 2. It is the neck part.

Reference numeral 4 denotes a fluorescent surface formed on the front part of the inner surface of the funnel part 2. Note that a shadow mask is disposed slightly behind the fluorescent surface 4 in parallel with the fluorescent surface 4.

5 is an electron gun disposed at the rear end of the neck portion 3, and the electron gun 5 has a red cathode (R cathode), a green cathode (G cathode), and a blue cathode (B cathode) arranged in-line. electron beams R and G from each cathode.
, B are radiated separately, and the electron beams R1G and B are focused by an electron lens provided on the neck portion 3, and a deflection yoke, which will be described later, is further deflected to emit the shadow. It is designed to collide with the fluorescent surface 4 through the mask.

(b, Deflection yoke) [Figures 1 and 2] 6 is a deflection yoke in which deflection coils are wound around a trumpet-shaped bobbin 7 above and below and on the left and right sides, and is located at the front end of the neck portion 3 of the picture tube 1. It is arranged in an externally fitted manner on the closer part.

Then, the electron beam R%G emitted from the electron gun 5
%B is the bobbin 7 when passing the front end of the neck part 3.
The bobbin 7 is deflected horizontally by deflection coils 8.8 wound symmetrically above and below the bobbin 7, and vertically by deflection coils 9.9 wound symmetrically on the left and right sides of the bobbin 7. Become.

(C, Convergence Yoke> [Figures 1 to 3] 10 is a convergence yoke disposed behind the deflection yoke 6, and the convergence yoke 10 has two U-shaped cores 11, 11 and the U-shaped core. It consists of convergence coils 12, 12, etc., each wound around a vertical piece 111, 111 of a shaped core 11, 11.

The core 11.11 is arranged so as to sandwich the neck portion 3 of the picture tube 1 from the left and right sides thereof, and its vertical pieces 11, . 11. Winter clothes protruding from both upper and lower ends of the deflection yoke 6 are arranged directly behind the deflection yoke 6 in such a direction as to protrude toward the neck portion 3 side.

Further, each convergence coil 12.12 is connected in series, and both ends thereof are connected to the convergence circuit 13, and a predetermined correction current synchronized with the sawtooth current flowing through the horizontal deflection coil 8.8 of the deflection yoke 6. is supplied to the convergence coil 12.12 by the convergence circuit 13.

When a correction current is supplied from the convergence circuit 13 to the convergence coil 12.12, a magnetic field is generated in the convergence yoke 10 between the tips of the core 11, upper arm 11u, and lower arm 11d2 on the right side when viewed from the front. Also, the left core 11. A magnetic field is generated between the tips of the upper arm 11ul and the lower arms 11,1. In addition, the left and right cores 11 and 11. The directions of the magnetic fields formed are opposite in the vertical direction.

Therefore, the electron beams R, G emitted from the electron gun 5,
The electron beams R and B on both sides of B are connected to the left and right cores 11. or 11. The three electron beams R%G%B are controlled to coincide with each other at any position on the fluorescent surface 4 by being deflected to the left or right under the influence of the magnetic field.

Reference numerals 14 and 14 denote damping circuits connected in parallel to each convergence coil 121 and 122, and each damping circuit 14 consists of a resistor 15 and a diode 16 connected in series to the resistor 15.

The leakage magnetic flux of the deflection yoke 6 is connected to the core 117.11 of the diode 16.16. The resistors 15 and 15 are connected in series in such a direction that no reverse magnetic field is generated due to the closed loop formed between each convergence coil 12 and each damping circuit 14 when absorbed by the magnetic field.

(d, Effect) [Fig. 4] However, the left and right cores 11 of such a convergence yoke 10. ．． 11. When the leakage magnetic flux of the deflection yoke 6 is absorbed by the left and right cores 11, . 11. Convergence coils 12. ．． 122 and each damping circuit 14, . An electromotive force is generated in a closed loop formed between
are inserted, no electromotive force is generated, and therefore no magnetic field in the opposite direction is formed due to leakage magnetic flux of the deflection yoke 6, and each convergence coil 12. ,s
22c Since no N-motive force is generated, convergence yoke 1
Of the zero induced magnetic field waveform 17, the voltage level of the H pulse 17a does not decrease.

(F-2, Second Embodiment) [Figure 5] Figure 5 shows the second embodiment 1 of the convergence yoke of the present invention.
8.

This convergence yoke 18 is similar to that of the first embodiment 1.
0 differs only in the shape of the core, the winding location of the convergence coil, and the connection method between the damping circuit and the convergence coil, so other parts are the same as the similar parts in the first embodiment. With the sign of
The explanation will be omitted.

(a, convergence yoke) [Fig.
Convergence coils 2 each wound around 19d
It consists of 0, 20°, etc.

The core 19.19 is disposed immediately behind the deflection yoke 6 so as to sandwich the neck portion 3 of the picture tube 1 from the left and right sides, and with each joint thereof protruding toward the neck portion 3 side. .

Further, each of the convergence coils 20, 20°, etc. are connected in series, and both ends thereof are connected to the convergence circuit 13, and a predetermined correction current is supplied to the convergence circuit 1.
3.

Then, from the convergence circuit 13, the convergence coils 20, 20. When the correction current is supplied to the convergence yoke 18, the right core 19. A magnetic field is generated between the convergence coils 201 and 202 wound around the upper arm 19u1 and the lower arm 19d, respectively, and the left core 19. A convergence coil 20 is wound around the upper arm 19u1 and the lower arm 19dl, respectively. A magnetic field is generated between and 204. In addition, the left and right cores 191 and 19. The directions of the magnetic fields formed in the two are opposite to each other in the vertical direction.

Therefore, the electron beam R1G emitted from the electron gun 5,
The electron beams R and B on both sides of B are connected to the left and right cores 19. or 19. Under the influence of the magnetic field, the three electron beams R%G and B are deflected to the left or right, and are controlled so that the three electron beams R%G and B coincide at any position on the fluorescent surface 4.

21+, 21t, 213.214 are each convergence coil 20. ~204 are damping circuits connected in parallel, and each damping circuit 21 includes a resistor 22 and a resistor 22.
and a diode 23 connected in series.

Diodes 23+, 232, 235, and 234 are connected to the core 19. Or each convergence coil 20 and each damping circuit 2 when 191C is absorbed
The resistors 221, 222, 223, and 224 are connected in series in such a direction that no reverse magnetic field is generated due to the closed loop formed between the resistors 221, 222, 223, and 224.

(b. Effect) Therefore, the left and right cores 19 of such a convergence yoke 18. , 19. When the leakage magnetic flux of the deflection yoke 6 is absorbed, the convergence coils 20. 204 and each of the damping circuits 211 to 214, an electromotive force is about to be generated in the closed loop formed between the diodes 23 and the damping circuits 211 to 214, but the direction in which the current of the electromotive force is flowing is opposite to the diode 23,
234 is inserted, no electromotive force is generated, so a magnetic field in the opposite direction to the leakage magnetic flux of the deflection yoke 6 is not formed, and each convergence coil 201 to
Since no electromotive force is generated at the convergence yoke 204, the voltage level of the H pulse 17a of the magnetic field waveform 17 of the convergence yoke 18 does not decrease.

(F-3, third embodiment) [Figure 6! Figure 6 shows the third embodiment 2 of the convergence yoke of the present invention.
4.

This convergence yoke 24 is similar to that of the second embodiment 18.
The only difference is the damping circuit and the connection method of the convergence coil, so the other parts are given the same reference numerals as the similar parts in the second embodiment.
The explanation will be omitted.

(a, damping circuit) [Figure 6] 251.252 is the resistor 26r, 262 and the resistor 26,
．． The diodes 27.262 are individually connected in series with each other. ．．
27□, and the damping circuit 25. are the right core 19, the upper arm 19u, and the lower arm 19
convergence coils 20.d and 20.d and connected in series. and 202 in parallel, and a damping circuit 25
2 is wound around the upper arm 19uI and lower arm 19d of the left core 19+, respectively, and is connected in parallel to both ends of a series circuit composed of convergence coils 203 and 204 connected in series.

In addition, the diode 2'711272 has leakage magnetic flux from the deflection yoke 6 to the core 19. and 191, each resistor 261.2 is oriented so that a reverse magnetic field is not generated due to the closed loop formed between the convergence coil 201, 202 or 20s, 204 and the damping circuit 251 or 25.
Connected in series with 6□.

(b. Effect) When the leakage magnetic flux of the deflection yoke 6 is absorbed by the left and right cores 19r, 19H of the convergence yoke 24, the left and right cores 19, . 191 respectively wound convergence coils 201, 202 or 203
．． 204 and each damping circuit 25. An electromotive force is about to be generated in the closed loop formed between Therefore, a magnetic field in the opposite direction to the leakage magnetic flux of the deflection yoke 6 is not formed, and each convergence coil 25. Since no electromotive force is generated between 254 and 254, the voltage level of the H pulse 17a of the induced magnetic field waveform 17 of the convergence yoke 24 does not decrease.

(G. Effects of the Invention) As is clear from the above description, the convergence yoke of the present invention is a convergence yoke for a picture tube equipped with three cathodes arranged in-line, and each of the convergence yokes has three cathodes arranged in-line. It is characterized in that a damping circuit consisting of a resistor and a diode connected in series with the resistor is separately connected in parallel to the wound coil.

Therefore, according to the convergence yoke of the present invention, even if the core of the convergence yoke absorbs the leakage magnetic flux of the one-plane yoke, the vibration in the induced magnetic field waveform is suppressed by the resistor connected in parallel to the convergence coil, and the vibration is suppressed by the resistor. The series-connected diodes can prevent the generation of a magnetic field that occurs when the core absorbs leakage magnetic flux from the deflection yoke, preventing unnecessary magnetic fields from forming in the convergence yoke and reducing the neck shadow margin. Desired convergence adjustments can be made.

In the above embodiments, the convergence yoke of the present invention is applied to the convergence yoke of a single electron gun three-electron beam type picture tube, but the convergence yoke of the present invention is not limited to this, and is applicable to a three-electron gun in-line arrangement image receiver. Of course, it can also be applied to pipes.

[Brief explanation of drawings]

Figures 1 to 4 show the first convergence yoke of the present invention.
Fig. 1 is a perspective view of a picture tube, and Fig. 2 is a perspective view of a picture tube.
3 is an enlarged front view schematically showing the convergence yoke. FIG. 4 is a waveform diagram showing the waveform of the induced magnetic field flowing through the core. FIG. FIG. 6 is an enlarged front view schematically showing a third embodiment of the convergence yoke of the present invention, and FIGS. 7 and 8 show an example of a conventional convergence yoke. 7 is an enlarged front view schematically showing the convergence yoke, FIG. 8 is a waveform diagram showing the waveform of the induced magnetic field flowing through the core, and FIGS. 9 and 10 show other examples of the conventional convergence yoke. FIG. 9 is an enlarged front view schematically showing the structure, and FIG. 10 is a waveform diagram showing the waveform of the induced magnetic field flowing through the core. Explanation of symbols 1... Picture tube. 10... Convergence yoke, 11r, 111... Core, 121.122... Convergence coil, 14
1.142 ...damping circuit, 151.152
...Resistance, 161.162 ...Diode, 18...Convergence yoke, 19,. 19. ... Core, 20, ~204 ... Convergence coil, 21,
~214...damping circuit, 221~224...
・ Rens, 23, to 234 ・ ・ ・ Diode, 24 ・ ・ ・ Converzence yoke, 251.252 ・ ・ ・ Dumping circuit, 26i, 26
2...Resistor, 27Is272...Diode Applicant Sony Corporation Figure 4 Induced magnetic field waveform f) Waveform diagram (conventional example) Figure 8 Figure 10 Procedural amendment (self-initiated) Case indication Heisei 1 Patent Application No. 16906 2゜Name of Invention Convergence Yoke 3. Relationship with the case of the person making the amendment

Claims (1)

[Claims] A convergence yoke for a picture tube having three cathodes arranged in-line, including a resistor and a diode connected in series to the coils wound around the left and right cores, respectively. A convergence yoke characterized by having damping circuits each connected in parallel.