JPS6321881Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a projection type cathode ray tube that has an improved mounting structure for a pilot magnet and a focus magnet that are attached to the outer periphery of the neck portion of a bulb.

Figure 1 shows an example of a projection cathode ray tube used in color projection television equipment, etc., where 1 is a concentric meniscus face plate with a target 2 formed at the center of the inner surface, and 3 is a concave spherical face plate on the inner surface. 5 is a neck portion extending outward from the center of the end plate 3; 6 is a cylindrical member having the face plate 1 and the end plate 3 sealed on both end surfaces; , the end plate 3, the neck portion 5, and the cylindrical member 6 form a valve 7. 8 is housed in the neck part 5. Electron guns 9 to 13 are housed in the neck part 5.
A deflection yoke, a convergence yoke, a centering magnet, a focus magnet, and a focus magnet are sequentially fitted onto the outer periphery of the magnet and fixed in position.

The deflection yoke 9, the convergence yoke 10, and the centering magnet 11 are attached to the end plate side end of the neck portion 5 in front of the electron gun 8, and the focus magnet 12 and the centering magnet 13 are attached at a constant interval to the electron beam. It is mounted near gun 8. The focus magnet 13 is made by stacking a plurality of ring-shaped magnets, and has the function of aligning the electron beam accelerated and emitted by the electron gun 8 with the center of the focus magnet 12. It acts to focus the electron beam. This focused electron beam is deflected by a deflection yoke 9 and scans the fluorescent film of the target 2 in front to form an image. This image is reflected by the mirror 4, becomes an enlarged light, passes through the face plate 1, passes through a spherical aberration corrector (not shown) placed in front of it, and is further condensed on a screen (not shown) in front of it. Image. The centering magnet 11 adjusts the position of the image on the screen, and the convergence yoke 10 adjusts the color shift of the image by aligning the lights from the plurality of cathode ray tubes on the screen.

The focus magnet 12 is housed in one storage case 14 and attached to the neck portion 5.
This focus magnet storage case 14 has a split cylindrical mounting part 14b integrally provided with a plurality of slits formed in the axial direction from the center of one side of an annular magnet storage part 14a. The focus magnet storage case 14 is fixed to the neck part 5 by wrapping a metal band 15 around the metal band 15 and tightening the metal band 15 with a screw 16. In addition, a plurality of pulley magnets 13 are fitted onto a flanged split cylindrical mounting bobbin 17, the mounting bobbin 7 is fitted into the neck portion 5, the metal band 18 is fitted onto the mounting bobbin 17, and the metal The band 18 is fixed to the neck portion 5 by tightening the screw 19.

Incidentally, the attachment positions of the focus magnet 12 and the focus magnet 13 on the network portion 5 are uniformly determined by the position of the electron gun 8.
Therefore, in the above-mentioned conventional structure in which both are attached through separate attachment members, it is necessary to measure the respective attachment positions of both and the distance between them on the neck portion 5, and furthermore, The number of parts increased and assembly workability was poor. Further, since the two metal bands 15 and 18 are used as fastening means to attach the two, the tightening force applied to the neck portion 5 becomes large, and there is a risk that the neck portion 5 may crack.

The present invention has been devised in view of the above problems, and provides a projection type cathode ray tube in which a focus magnet and a focus magnet are attached to the neck portion of the bulb using one assembly member.

Hereinafter, the present invention will be applied to the cathode ray tube shown in FIG. 1, and each embodiment will be explained.

In FIG. 2, the same reference numerals as in FIG. 1 indicate the same parts, and details are omitted. 20 is a common mounting bobbin for attaching the focus magnet 12 and the focus magnet 13 to the neck portion 5; 21 is the mounting bobbin 2;
0 is a metal band fastened to the neck part 5, and 22 is a screw for tightening the metal band 21. As shown in FIG. 3, the mounting bobbin 20 is made of resin and has a flange portion 20b integrally formed at one end of a split cylindrical mounting portion 20a. Focus magnet 12 and focus magnet 13 installed at intervals
is set slightly larger than the sum of the width and spacing. At important points on the outer periphery of this axially divided attaching part 20a, a focus magnet storage case 23 for storing the focus magnet 12 and protrusions 24, 24 for positioning a plurality of stacked focus magnets 13 are provided. ...is integrally protruded.

Before inserting the mounting bobbin 20 into the neck part 5, both the focus magnet storage case 23 and the focus magnet 13 can be attached together by slightly deforming the mounting parts 20a at both ends of the mounting part 20a. Positioned and inserted. Then, insert the mounting bobbin 20 into the neck portion 5 until it reaches the fixed position.
The mounting portion 20a is fixed to the neck portion 5 by tightening a metal band 21 approximately at the center thereof. In this way, since the focus magnet 12 and the focus magnet 13 are previously positioned at a constant interval on the mounting bobbin 20, the positioning of both with respect to the neck portion 5 is as follows: This is done by positioning.

Next, another embodiment of the present invention will be described with reference to FIG.
The inner diameter of this is slightly larger than the outer diameter of the neck part 5,
A focus magnet storage case 26 having a flange portion 27 formed at one end of the outer periphery is attached to the flange portion 27.
facing the flange portion 25b at one end of the mounting bobbin 25 on which the pulley magnet 13 is attached,
Both flanges 25b and 27 are screwed together at at least three points. This screw is screw 2
The spring 29 inserted through 8 is attached to both flanges 25.
This is done by interposing it between b and 27. The pulley magnet 13 is positioned and inserted into one end of the split cylindrical attachment portion 25a of the attachment bobbin 25, and the attachment bobbin 25 is positioned at a fixed position on the neck portion 5 at the attachment portion 25a.
It is fixed by tightening with a metal band 30.

According to the embodiment shown in FIG. 4, the focus magnet storage case 26 is loosely fitted into the neck portion 5 so as to be freely movable in the axial direction and to be able to slightly adjust the tilting movement, so that the amount of tightening of at least three screws 28 can be adjusted. Through adjustment, the axial position on the neck portion 5 can be finely adjusted, and the inclination angle can also be finely adjusted. This fine adjustment of the inclination is performed so that the center of the focus magnet 12 is aligned with the center of the electron gun 8 in the network portion 5.

Note that the present invention is not limited to the above-mentioned embodiments, and in particular, the mounting bobbin may be a cylindrical body with a flange, and a cylindrical spacer with a large diameter may be used to connect the focus magnet and the focus magnet. You may also set an interval. Further, this mounting bobbin can be modified in various ways, for example, it may have a structure in which it is simply screwed on without using a metal band.

As explained above, this device uses a common mounting bobbin to mount the focus magnet and the purity magnet to the neck of the valve, which reduces the number of parts required for mounting, makes it easier to position both magnets on the neck, and greatly improves assembly work. Also, the tightening torque to the neck is reduced, protecting the outer surface of the neck and eliminating the risk of damage to the neck, improving yield and making the assembly work safer.

[Brief explanation of the drawing]

Fig. 1 is a partially cross-sectional side view of a projection type cathode ray tube which is the premise of the present invention, Fig. 2 is a partially cross-sectional side view showing an embodiment of the present invention, and Fig. 3 is a view of the mounting bobbin in Fig. 2. FIG. 4 is a perspective view showing one specific example; and FIG. 4 is a partially sectional side view showing another embodiment of the present invention. 5...Network part, 7...Valve, 12...Focus magnet, 13...Pullity magnet, 20...Mounting bobbin, 23...Focus magnet storage case, 25...Mounting bobbin, 26
...Focus magnet storage case.

Claims (1)

[Scope of utility model registration request] A projection type cathode ray characterized in that an annular pulley magnet and a focus magnet are positioned and attached to a mounting bobbin, and the mounting bobbin is inserted and fixed at a fixed position on the outer periphery of a valve neck. tube.