JPH11312475A - Cathode-ray tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cathode-ray tube that has a high breakdown voltage and can easily be manufactured at low cost. SOLUTION: This cathode-ray tube is provided with an inside magnetic shield body 50 installed in its inside opposite to a support member 40. The support member 40 supports a color selection body 30 and has a pair of frame members 41 and a pair of arm members 42 straddling between them. The inside magnetic shield body 50 has a shield part 51 formed into a truncated quadrangular-pyramid funnel-like shape, a pair of mounting parts 52 each are individually formed on one of its opposite pairs of base sides, and two pairs of locked parts 55 each are individually formed on the other opposite pair of base sides. The inside magnetic shield body 50 is fixed in one direction by locking each fixing means 53 to the arm member 42 through an opening 54 of each of the mounting parts 52 and is fixed in the other direction perpendicular to the one direction by locking each of the locked parts 55 to the corresponding arm member 42. Thereby, the magnetic shield body 50 can be fixed with a simple structure without welding it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cathode ray tube having an internal magnetic shield for eliminating the influence of terrestrial magnetism.

[0002]

2. Description of the Related Art In general, in a cathode ray tube, when affected by terrestrial magnetism, the trajectory of an electron beam emitted from an electron gun is bent, so that the electron beam does not collide with a fluorescent screen that is correct in design, and the other fluorescent light is emitted. Collide with the surface. Therefore, a cathode ray tube may be provided with an internal magnetic shield as one method of eliminating such an influence of geomagnetism. The internal magnetic shield is provided, for example, inside a cathode ray tube with respect to a support member for supporting a color selector disposed so as to face the phosphor screen.

FIG. 4 shows a configuration example of an internal magnetic shield 50 and a support member 40 in a conventional cathode ray tube. As described above, in the conventional cathode ray tube, the mounting opening 47 is formed in the temperature change adjusting member 46 welded to the support member 40, and the opening 54 for mounting the internal magnetic shield 50 is overlapped with this opening 47. Fixing tool 53
Is inserted, the internal magnetic shield 50 is disposed with respect to the support member 40.

In a conventional cathode ray tube, although not shown, the mounting portion of the internal magnetic shield 50 may be directly provided by welding to the support member 40 in some cases.

[0005]

However, in the conventional cathode ray tube in which the internal magnetic shield 50 is disposed using the temperature change adjusting member 46 as described above, the opening 47 for attachment is formed in the temperature change adjusting member 46. Since the temperature change adjusting member 46 needs to be formed, the shape of the temperature change adjusting member 46 becomes complicated, and there is a problem that material costs and processing costs increase.
Further, in the configuration in which the internal magnetic shield body 50 is directly disposed on the support member 40 by welding, sparks generated at the time of welding remain inside the cathode ray tube as foreign matter, and when a high voltage is applied, the spark is generated. There is a problem that discharge is caused by the foreign matter and the withstand voltage capability is reduced.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a cathode ray tube which has a high pressure resistance and can be easily manufactured at low cost.

[0007]

SUMMARY OF THE INVENTION A cathode ray tube according to the present invention has a panel portion on which a phosphor screen is formed, and a color panel having an opening through which an electron beam passes and which is disposed to face the phosphor screen of the panel portion. A sorting member, a support member that supports the color sorting member and has a stepped portion, an internal magnetic shield body that is disposed on the support member by a mounting portion and that eliminates the influence of geomagnetism, A fixing tool for fixing the internal magnetic shield to the support member using the mounting portion and the step of the support member.

In the cathode ray tube according to the present invention, the inner magnetic shield is fixed to the supporting member by the fixture using the mounting portion and the step portion. The electron beam thus passes through the inside of the internal magnetic shield provided on the support member, passes through the opening of the color selector supported by the support member, and collides with the fluorescent screen of the panel section.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a partial sectional view of a cathode ray tube according to an embodiment of the present invention, and FIG. 2 is an exploded view of the inside of the cathode ray tube shown in FIG. This cathode ray tube
It has a panel section 10 having a fluorescent screen 11 formed inside and a funnel section 20 having an electron gun 21 built-in. The panel section 10 and the funnel section 20 have their openings 1
At 22, 22, they are fused together and their interior is maintained in a high vacuum. It should be noted that a striped pattern (not shown) made of a phosphor is formed on the phosphor screen 11.

A color selector (aperture grill) 30 made of a thin metal plate is disposed inside the panel section 10 so as to face the phosphor screen 11. This color sorter 30
An opening (not shown) through which the electron beam M emitted from the electron gun 21 passes is formed in a stripe shape corresponding to the pattern of the phosphor screen 11. The color selector 30 is supported by a metal support member 40 so that the distance between the color selector 30 and the fluorescent screen 11 is constant.

The support member 40 includes a pair of opposed frame members 41 welded to the color selection body 30, and a pair of the frame members 41.
And a pair of arm members 42 inserted between both ends thereof so as to cross each other. An elastic support member (spring) 43 is welded to each frame member 41 and each arm member 42 on a surface facing the panel portion 10. These elastic support members 43 are for arranging the support members 40 with respect to the panel portion 10, and engaging holes 44 formed in the elastic support members 43 respectively correspond to the inner peripheral surfaces of the panel portion 10. The projections 13 formed are engaged with each other to be fixed. In addition, one frame member 41 is provided with an elastic joining member 45 for joining the panel section 10 and the funnel section 20.

A temperature change adjusting member (self-thermo control) 46 made of a metal rectangular thin plate is welded to each arm member 42 on the surface opposite to the color selecting body 30. The temperature change adjusting member 46 is made of a metal different from that of the arm member 42. Even when the temperature changes due to the bimetal effect utilizing the difference in thermal expansion coefficient, the distance between the color selection body 30 and the fluorescent screen 11 is changed. Can be kept constant. Note that the arm member 42 is disposed at an interval from the color selection body 30, and a surface 42 a of the arm member 42 on the color selection body 30 side is fixed to a fixing tool 53, which will be described later.
And functions as a step for locking in the vertical direction.

Inside the panel section 10, the electron gun 2 is provided.
An internal magnetic shield 50 is provided to prevent the electron beam M emitted from 1 from being affected by terrestrial magnetism. The inner magnetic shield 50 has a thickness of 0.1
It is formed by combining several ferromagnetic metal plates mainly composed of iron of about 1.0 mm, and has a shield part 51 in the shape of a truncated quadrangular pyramid funnel. The shield portion 51 has a pair of mounting portions 52 for disposing the internal magnetic shield 50 on the support member 40 (specifically, the arm member 42) on a pair of opposed bottom sides of the truncated pyramid. Are formed respectively. The fixing parts 5 are attached to these mounting portions 52.
Two openings 54 for inserting the three are formed in a size corresponding to the fixture 53, respectively.

The fixing tool 53 is substantially U-shaped, and each open end 53a is bent inward. As shown in FIG. 3, the fixing tool 53 has one open end 5.
3a is inserted into the opening 54 of the inner magnetic shield 50, and the arm member 42 is surrounded from the side of the temperature change adjusting member 46, and both open ends 53a are separated from the color sorter 3 of the arm member 42.
The internal magnetic shield 50 is fixed to the support member 40 by being locked to the 0-side surface 42a.

Incidentally, the arm member 42 is not provided with a special step for locking the fixing tool 53 in the length direction of the arm member 42. That is, the internal magnetic shield 5
In the case of 0, one direction (here, a direction perpendicular to the length direction of the arm member 42) is mainly fixed by the mounting portion 52.

The shield portion 51 is also provided with two pairs of locking portions 55 on the other pair of opposing bottom sides of the truncated pyramid. These locking portions 55 are partially supported by the support member 40 (here, the end surface 42 in the length direction of the arm member 42).
By locking in b), the fixing of the internal magnetic shield 50 in the other direction perpendicular to one direction (here, the length direction of the arm member 42) is assisted.

This cathode ray tube is manufactured as follows.

First, each temperature change adjusting member 46 and each arm member 42 are prepared and welded to each other. Next, the color selection body 30, each frame member 41, each elastic support member 4
3 and the elastic joining member 45 are prepared, respectively, and the color selection body 30 and each frame member 41, each frame member 41 and each arm member 42, each frame member 41 and each elastic supporting member 43, each elastic joining member 45, and each arm member are prepared. 42 and each elastic support member 43 are welded. Thus, the color selection body 30 is disposed on the support member 40.

Subsequently, an internal magnetic shield body 50 is prepared, and each locking portion 55 is disposed on the support member 40 so as to correspond to the surface 42a in the length direction of each arm member 42. After that, each fixing tool 53 is inserted into each opening 54, and each mounting portion 52 and each arm member 42 are fixed respectively.

Next, the panel section 10 is prepared, and the respective engaging holes 44 of the respective elastic support members 43 are respectively inserted into the respective projection sections 1 of the panel section 10.
The support member 40 is disposed inside the panel portion 10 by engaging with the respective members 3. Subsequently, a funnel portion 20 in which an electron gun 21 is disposed is prepared and joined to the panel portion 10. Thus, the cathode ray tube shown in FIG. 1 is manufactured.

In the cathode ray tube manufactured as described above, the electron beam M emitted from the electron gun 21 passes through the inside of the internal magnetic shield 50 and passes through the opening (not shown) of the color selector 30. And collides with the phosphor screen 11. The electron beam M is free from the influence of terrestrial magnetism by the internal magnetic shield 50, so that the fluorescent screen 11
Collide with Thereby, an appropriate display is performed on the surface of the panel unit 10. In this case, since the inner magnetic shield 50 is fixed by the fixture 53 and the locking portion 55, the inside of the cathode ray tube has a small amount of foreign matter due to welding, and discharge by the foreign matter is less likely to occur. Is high.

As described above, the cathode ray tube according to the present embodiment is provided with the fixing member 53 and the locking portion 55 using the opening 54 of the mounting portion 52 and the step portion of the arm member 42. The internal magnetic shield 50 can be fixed to the support member 40 with a simple structure and without using welding. Therefore, unlike the related art, there is no need to process the temperature change adjusting member 46 into a complicated shape, and the temperature change adjusting member 46 can be easily manufactured at low cost. Further, the weight of the temperature change adjusting member 46 can be reduced by almost 50% as compared with the conventional case, so that the material cost can be reduced, the packing efficiency of parts can be improved, and the transportation cost can be reduced. . Further, the amount of foreign matter in welding inside the cathode ray tube can be reduced, and discharge due to the foreign matter can be prevented. That is, the withstand voltage capability can be increased.

The present invention has been described with reference to the embodiment. However, the present invention is not limited to the above embodiment, and can be variously modified. For example, in the above-described embodiment, a step for locking the fixing tool 53 is not formed in the length direction of the arm member 42, but a step is also formed in the length direction of the arm member 42. You may. In that case, the locking portion 55 can be omitted from the internal magnetic shield 50.

In the above-described embodiment, two openings 54 are formed in each mounting portion 52 of the internal magnetic shield 50. However, the number of openings 54 may be any number. A different number of openings 54 may be formed, or may be formed at positions that do not face each other.

Further, in the above embodiment, the opening 54 corresponding to the size of the fixture 53 is formed, but an opening larger than the fixture 53 may be formed. A plurality of fixtures 53 may be inserted into one opening.

In addition, in the above-described embodiment, a pair of mounting portions 52 are formed on the shield portion 51, respectively.
May be formed, and a different number of mounting portions 52 may be formed on a pair of opposed bases.

Furthermore, in the above embodiment, each locking portion 55 of the internal magnetic shield 50 is locked to the end surface 42b in the length direction of the arm member 42. You may make it lock.
In addition, two pairs of locking portions 55
Are formed, but the number of the locking portions 55 may be any number, and a different number of the locking portions 55 may be formed on the other pair of opposite bases.

[0029]

As described above, according to the cathode ray tube of the present invention, since the fixture using the mounting portion and the step portion is provided, the internal magnetic shield is formed with a simple structure and without using welding. The body can be fixed to the support member. Therefore, it is possible to simplify the shape of the temperature change adjusting member, and it is possible to easily manufacture the temperature change adjusting member at low cost. Further, the weight of the temperature change adjusting member can be reduced, so that the material cost can be reduced, the packing efficiency of parts can be improved, and the transportation cost can be reduced. Further, it is possible to reduce the amount of welding foreign matter inside the cathode ray tube, prevent discharge due to foreign matter, and increase the pressure resistance.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view illustrating a configuration of a cathode ray tube according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a configuration of a support member and an internal magnetic shield in the cathode ray tube shown in FIG.

FIG. 3 is a partial cross-sectional view of the cathode ray tube shown in FIG. 1, taken along the line II.

FIG. 4 is a perspective view illustrating a configuration of a conventional cathode ray tube.

[Explanation of symbols]

10 panel part, 11 phosphor screen, 12, 22 opening part,
13 Projection, 20 Funnel, 21 Electron gun, 3
0: color sorter, 40: support member, 41: frame member, 42:
Arm member, 43: elastic support member, 44: engagement hole, 45: elastic joining member, 46: temperature change adjusting member, 50: internal magnetic shield body, 51: shield portion, 52: mounting portion, 53 ...
Fixing tool, 53a: open end, 54: opening, 55: locking part, M: electron beam

Claims (4)

[Claims] 1. A panel on which a fluorescent screen is formed, a color selector disposed opposite to the fluorescent screen of the panel and provided with an opening through which an electron beam passes, and a support for the color selector. A support member having a stepped portion, an inner magnetic shield body disposed by a mounting portion with respect to the support member to eliminate the influence of geomagnetism, a mounting portion of the internal magnetic shield body, and a stepped portion of the support member And a fixture for fixing the internal magnetic shield to the support member by utilizing the above. 2. The cathode ray tube according to claim 1, wherein the internal magnetic shield is fixed in at least one direction by a mounting portion, and further has a locking portion for fixing the other direction. . 3. The cathode ray tube according to claim 1, wherein the internal magnetic shield has an opening in a mounting portion into which the fixing tool is inserted. 4. The support member has a pair of frame members disposed on the color selection body, and an arm having a step formed by intersecting each of the pair of frame members. The cathode ray tube according to claim 1, further comprising a member.