JPS639985Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a color picture tube equipped with a magnetic material for convergence and purity adjustment inside or outside the neck portion, and in which the magnetic material is composed of two symmetrical semicircular structures. This relates to color picture tubes.

An example of a conventional color picture tube will be explained with reference to FIG.

That is, a panel 2 has a phosphor screen 1 adhered to its inner surface, in which phosphor layers each emitting a different emission color are arranged in a controlled manner by the impact of an electron beam, and a funnel 4 is attached to the side wall 3 of this panel 2. A net 5 connected to the net 5, an electron gun 6 housed in the net 5, a stem pin 7 for applying a predetermined voltage to the electron gun 6, and a static convergence device provided on the outer wall of the net 5 opposite to the electron gun 6. and a color purity adjustment magnet 8, a deflection device 9 attached to the outer wall from the funnel 4 to the neck 5, and a shadow mask 10 disposed opposite the phosphor screen 1 at a predetermined distance. When the picture tube is completed or incorporated into a television receiver and operated, the adjustment magnet 8 is used to adjust the static convergence and color purity of the electron beam with the phosphor screen 1. The adjustment magnet 8 described above generally uses two magnets each having two magnetic poles, four magnetic poles, and six magnetic poles, and these magnets are used to adjust the static convergence and color purity of the electron beam. However, although the adjustment of these magnets is carried out by skilled workers, it takes a considerable amount of time, and the work is done based on experience, so the current situation is that the adjustment is not sufficiently accurate. It is.

In order to compensate for this drawback, a color picture tube has been proposed in which the above-mentioned adjusting magnet 8 can be omitted.

An example of such a color picture tube is shown in FIG.
In the figure, the same reference numerals as in FIG. 1 indicate the same parts, and no particular explanation will be given.

That is, in this color picture tube, between the electron gun 6 and the inner wall of the net 5, one or more magnetizable, substantially annular magnetic bodies 11 are arranged with 2 poles, 4 poles, 6 poles, 12 poles, etc. It is polarized and magnetized to form a magnetic pole, and has the same function as the adjustment magnet 8 shown in FIG.

A color picture tube with such a structure is, for example, developed by Japanese Patent Publication No.
This is disclosed in JP-A No. 52-117512, Japanese Patent Application Laid-Open No. 18235-1982, US Pat. No. 4,162,470, and US Pat. No. 4,138,628. The structure of the magnetic material of such a color picture tube is mostly a ring-shaped strip, a ring-shaped structure with one gap, or a strip-shaped structure with a groove-shaped gap at one place.

The use of such a magnetic material is very inconvenient when it is attached to an electron gun. For example, as shown in FIG. 3, the electron gun 6 includes a positioning electrode 7, a positioning structure 8 attached to the positioning electrode 7, an electrode 9 for converging an electron beam (not shown), and a cathode for generating the electron beam. 13 and the stem pin 1 for applying voltage and supplying current to the electrode 9
0 and a stem 12. For example, when attaching it to the positioning electrode 7, it must be attached to the positioning electrode 7 in advance and then assembled, which complicates the work and also precludes automated assembly, leading to an increase in the number of steps. . Alternatively, even when the gap of the ring-shaped permanent magnet is widened and it is attached to the electron gun 6, it is very difficult to attach it because the positioning structure 8 or the stem 12 is large. This also increases the number of steps and makes automatic assembly difficult. Furthermore, machining the metal into a ring shape or circular ring shape results in wasted material, leading to an increase in material costs, or machining the metal into a circular ring shape, resulting in an increase in processing costs.

In view of the above circumstances, it is an object of the present invention to provide a color picture tube that can be manufactured at low cost and that can perform convergence/pilarity correction using a magnetic material that can be easily attached.

Examples thereof will be described below with reference to the drawings. Fourth
The figure shows a preferred embodiment of the invention. In FIG. 4, the applied color picture tube main body is the same as that shown in FIG. 1, so a description thereof will be omitted. In FIG. 4, the magnetic body 15 is separated into two parts via a gap, and is attached to the positioning electrode 7 of the electron gun 6, for example, with gaps 16 provided at the top and bottom of the positioning electrode. The gap 16 at this time must be narrower than the magnetized region when a magnetic field is applied and magnetized. It takes. In the example, since the gap 16 is provided symmetrically with respect to the tube axis, no non-uniform magnetic field is generated, and therefore no inconvenience occurs. In this embodiment, the magnetic body 15 is attached to the positioning electrode 7, but it is of course possible to attach it to the electrode assembly 9 of the electron gun 6. In FIG. 4, the gap 16 of the magnetic body 15 is provided at the top and bottom, but as shown in FIG. 5, the gap 16 may be placed symmetrically on the horizontal axis as in the case of the electron beam. Here, on the horizontal axis, the gap 16 is close to the blue electron beam 17a and the red electron beam 17c, but since the gaps 16 are symmetrically provided, the imbalance of correction due to the imbalance of the magnetic field with respect to the electron beam, Electron beams 17a, 17 due to disturbance of magnetic field
b, 17c will not have any adverse effects such as distortion.

FIG. 6 is a sectional view showing the arrangement of the magnetization device 18 and the magnetic material for convergence and purity adjustment suitable for the present invention. The magnetizing device 18 preferably comprises a multi-pole magnetic pole 19 and a coil 20 wound thereon. The gap 16 of the magnetic body 15 is located at a position corresponding to the top and bottom magnetic poles 19 in FIG. The magnetic poles 19 of this magnetizing device 18 are not limited to 8 poles as shown in FIG. 6, but are 4 poles, 2 poles, or 12 poles.
It is okay to be extreme. Further, the coils wound around each magnetic pole 19 may supply current individually, or may be connected in series or parallel to each other.

The magnet of the present invention may be attached using resistance welding, laser welding, or the like. Moreover, the magnetic body 15 can also be installed outside the color picture tube.

As described above, according to the present invention, attachment of the magnetic body 15 is extremely easy, automatic assembly is possible, and it is also possible to reduce the cost of magnetic material and processing cost, which has great industrial value. big.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a conventional color picture tube, FIG. 2 is a sectional view showing another conventional color picture tube, and FIG. 3 is an external view showing an example of an electron gun used in the color picture tube. 4 and 5 are cross-sectional views showing how the magnetic material applied to the color picture tube of the present invention is installed, and FIG. 6 is a schematic diagram showing the external view of the magnetizing device and the external view of the magnetic material. . 5...Neck part, 15...Magnetic material, 16...Gap.

Claims (1)

[Scope of utility model registration request] In a color picture tube equipped with a magnetic body for convergence and purity adjustment inside or outside the neck part of the color picture tube, the magnetic body is constituted by two symmetrical semicircular structures and is attached to the color picture tube. A color picture tube characterized in that the gap of the semicircular structure is narrower than the magnetic pole formed in the magnetic material.