JP2002042642A - Material for inner magnetic shield, inner magnetic shield, method of manufacturing inner magnetic shield, and cathode-ray tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the cost of an inner magnetic shield in a cathode-ray tube. SOLUTION: A short side flat magnetic shield half 54 [54a, 54b] forming the inclined short side extending at the specified angle to the long side through each of bent parts 71, 72, and an inner beam flat shield half 56 [56a, 56b] are integratedly formed on one side and the other side of a long side flat magnetic shield part 53 forming an inclined long side. The bend 72 of the inner beam shields 52a, 52b is formed of two inner magnetic shields 52A, 52B formed in a fan shape, two inner magnetic shields 52A, 52B are bent, and the short side magnetic shield halves 54a and 54b are connected each other, and inner beam shield halves 56a and 56b are also connected each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a member for forming an internal magnetic shield, an internal magnetic shield structure formed from the member for forming an internal magnetic shield, a method of manufacturing the internal magnetic shield structure, and an internal magnetic shield. The present invention relates to a cathode ray tube having a structure.

[0002]

2. Description of the Related Art An internal magnetic shield (IMS) for shielding terrestrial magnetism is required inside a cathode ray tube.
An inner beam shield (IBS) for blocking an electron beam going outside the effective screen is required. Some cathode ray tubes are provided with an IMS and an IBS independently of each other, but in order to achieve a lower price, an integrated IMS and IBS has been developed.

FIG. 10 is an exploded perspective view of such a cathode ray tube. In the figure, 1 is a funnel, 2 is a neck portion in which an electron gun 3 is built, and 4 is an internal magnetic shield (IM).
S) shows a structure. The internal magnetic shield structure 4 includes a long-side magnetic shield portion 5a and a short-side magnetic shield portion 5b.
c, 5d, and these magnetic shield portions 5a to 5d
Are inclined at a predetermined angle with respect to a plane perpendicular to the central axis of the cathode ray tube to achieve a predetermined geomagnetic shielding effect.
On the short side, inner beam shields (IBS) 6a and 6b for blocking unnecessary electron beams that have been horizontally overscanned continuously to the short side magnetic shield portions 4c and 4d.
Are integrally formed.

[0004] Reference numeral 7 denotes a color selection mechanism called an aperture grill. The color selection mechanism 7 includes a pair of opposing support members 8 and 9 and an elasticity imparting member 1 joined between both ends thereof.
A color selecting electrode thin plate 13 having a large number of slit-shaped electron beam transmitting holes is stretched over a frame-shaped metal frame 12 consisting of 0 and 11 so as to extend between supporting members 8 and 9. Is done. 14 is a glass panel. The internal magnetic shield structure 4 is disposed in the tube while being attached to the color selection mechanism 7.

A conventional internal magnetic shield structure 4 is shown in FIG.
As shown in the (exploded view), it is assembled from three members 21, 22 and 23, which are called a three-part type and are stamped. The member 21 includes the long side magnetic shield portions 5a and 5b and the short side inner beam shields 6a and 6a.
This is a press-formed member having b in one piece and forming welded attachment portions 24 to be welded to the support members 8 and 9 of the frame of the color selection mechanism 7 on each long side. Members 22 and 23 are
These are press-formed members that become the short-side magnetic shield portions 5c and 5d, respectively. In FIG. 8, m ₁ indicated by a two-dot chain line,
m ₂ is a bending line. As shown in FIG. 9, these three members 21, 22 and 23 are bent at each bending portion,
The members 22 and 23 which are the short side magnetic shield portions are fixed to the long side magnetic shield portions 5a and 5b of the member 21 by welding or the like, respectively, to form the internal magnetic shield structure 4.

[0006]

By the way, the internal magnetic shield structure 4 shown in FIG. 9 is composed of members 21, 22 and 23 formed by three press workings, and in particular, the member 21 becomes a pair of long side slopes. Long side magnetic shield portions 5a, 5
b and a pair of short side inner beam shields 6a, 6b
Because of the integrated shape of the above, it becomes a large part, and the cost of the die and the handling at the time of press working is increased. Also, since it is a three-part type, the mold
Three types and members (21, 22, and 23) were required, and the cost was inevitable in terms of the number of parts, the number of man-hours, and the like.

SUMMARY OF THE INVENTION In view of the above, the present invention provides a member for forming an internal magnetic shield, an internal magnetic shield structure, and a method of manufacturing the same, which can be configured at low cost with a small number of components without deteriorating the geomagnetic shield characteristics (geomagnetic drift). Is provided. The present invention provides a cathode ray tube provided with such an internal magnetic shield structure.

[0008]

A member for forming an internal magnetic shield according to the present invention has bent portions on one and the other sides of a plate-like long side magnetic shield portion which is a long side slope portion. A plate-shaped short side magnetic shield half which becomes a slope on the short side extending at a predetermined inclination angle with respect to the long side through the plate, and a plate inner beam along the short side magnetic shield half The shield half is integrally formed, and the bent portion of the inner beam shield half is formed in a fan shape so that the inner beam shield half is perpendicular to the long side during bending.

In the member for forming an internal magnetic shield according to the present invention, an internal magnetic shield structure can be formed by using the two members for forming an internal magnetic shield having the same shape. The number of members for forming the internal magnetic shield required for forming the internal magnetic shield structure is reduced to two from the conventional three. Since the members for forming the internal magnetic shield may have the same shape, only one mold is required for forming the member for forming the internal magnetic shield. The shape of the member for forming the internal magnetic shield is such that the short-side magnetic shield half and the inner beam are extended on both sides of the long-side magnetic shield portion at predetermined inclination angles with respect to the long side through the bent portions respectively. Since the shield half is formed in a substantially U-shape in which the shield half is integrally formed, the whole is made compact, and waste of a plate material in press punching can be reduced.

[0010] The internal magnetic shield structure according to the present invention has a plate-like long side magnetic shield portion serving as a slope portion on the long side side, and one side and the other side of the plate-like long side magnetic shield portion, which are respectively bent to the long side. A plate-shaped short side magnetic shield half which becomes a short side slope portion extending at a predetermined inclination angle, and a plate-shaped inner beam shield half along the short side magnetic shield half are integrally formed. The inner beam shield half is formed of two internal magnetic shield forming members each having a bent portion formed in a fan shape. The body and the inner beam shield halves are connected to each other.

The internal magnetic shield structure of the present invention is composed of two internal magnetic shield forming members having the same shape, so that the cost can be reduced. Structurally, the magnetic shield portion has the inner beam shield portion, so that the cost can be reduced without deteriorating the terrestrial magnetism shield characteristics and the shield characteristics of the horizontal overscan unnecessary electron beam as in the related art.

According to the method of manufacturing an internal magnetic shield structure according to the present invention, one side and the other side of a plate-shaped long-side magnetic shield portion which is a long-side slope portion are respectively provided on the long-side side via a bent portion. The plate-shaped short side magnetic shield half that becomes the short side slope portion extending at a predetermined inclination angle with respect to the plate, and the plate-shaped inner beam shield half that follows this short side magnetic shield half The inner magnetic shield half is formed into a fan-shaped bent portion, and two internal magnetic shield forming members are prepared. Each of the internal magnetic shield forming members is bent, and the long side magnetic shield portion and The short side magnetic shield halves are inclined surfaces, and each inner beam shield half is perpendicular to the long side, and the two internal magnetic shield forming members are connected to each other on the short side magnetic shield halves. Connect with emissions donors beam shield halves together to produce a single internal magnetic shield structure.

In the method of manufacturing an internal magnetic shield structure according to the present invention, two internal magnetic shield forming members having the same shape are prepared, and the short side magnetic shield halves are connected to each other, and the inner beam shield halves are connected to each other. Therefore, only one type of molding die is required for the member for forming the internal magnetic shield, and the number of materials (the number of parts), material waste, and assembly man-hours are reduced. Handling of the member for forming the internal magnetic shield during assembly is also easy, and assembly is facilitated.

The cathode ray tube according to the present invention has a plate-shaped long-side magnetic shield portion which is a slope on the long side and is provided with a predetermined angle with respect to the long side through a bent portion. A plate-shaped short side magnetic shield half which becomes a slope portion on a short side extending at an inclination angle, and a plate-shaped inner beam shield half along the short side magnetic shield half are integrally formed, and the inner The beam shield half is formed of two internal magnetic shield forming members in which a bent portion is formed in a fan shape, and the two internal magnetic shield forming members are bent respectively, and the short side magnetic shield halves are mutually joined. And an internal magnetic shield structure connected between the inner beam shield halves.

Since the cathode ray tube of the present invention includes the above-mentioned internal magnetic shield structure, the cost can be reduced while maintaining the same terrestrial magnetic shield characteristics and the horizontal overscan unnecessary electron beam shield characteristics as in the prior art.

[0016]

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

FIG. 1 shows a cathode ray tube having an internal magnetic shield structure according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view thereof. The cathode ray tube 31 according to the present embodiment
Is a funnel 33 having a neck portion 32 and a panel 34.
A cathode ray tube 35 is formed, and a phosphor screen, in this embodiment, a color phosphor screen 36 composed of red (R), green (G) and blue (B) phosphor strips and a carbon stripe is formed on the inner surface of the panel 34. A color selection mechanism 37 is disposed facing the fluorescent screen, and an internal magnetic shield structure 50 of the present invention described later is attached to the color selection mechanism 37,
Further, an electron gun 38 is arranged in the neck portion 32.
Reference numeral 39 denotes a fastening band wound around the outer periphery of the panel 34.

The color selection mechanism 37 is constituted by, for example, an aperture grill similar to that described above, and comprises a pair of opposing support members 41 and 42 and an elasticity imparting member 4 joined between both ends thereof.
3 and 44, a color selecting electrode thin plate 46 having a large number of slit-shaped electron beam transmitting holes is stretched over a frame-shaped metal frame 45 made of a plurality of slits so as to extend between the supporting members 41 and 42. . Reference numeral 47 denotes a support spring attached to the frame 45, and reference numeral 48 denotes a metal plate (referred to as an STC plate) which is fixed to the lower surfaces of the elasticity applying members 43 and 44 and forms a bimetal structure with the elasticity applying members. Reference numeral 49 denotes a panel pin provided on the inner surface of the skirt portion of the panel 34.

In the cathode ray tube 31, the electron beam 30 emitted from the electron gun 38 is shielded from terrestrial magnetism by the internal magnetic shield structure 50, so that mislanding of the electron beam 30 due to terrestrial magnetism is avoided.

FIG. 3 shows an internal magnetic shield structure 50 according to one embodiment. The internal magnetic shield structure 50 is composed of two internal magnetic shield forming members 52 [52A, 52B] of the same shape formed by press punching. The internal magnetic shield forming member 52 is made of, for example, a thin steel material or the like, and as shown in FIG. 5 (a development view before bending), a plate-shaped long-side magnetic shield portion 52 that becomes a long-side slope portion. A plate-shaped short-side magnetic shield half 54 that becomes a short-side slope portion extending at a predetermined inclination angle via bent portions 71 and 72 on one side and the other side, respectively.
[54a, 54b] and the short side magnetic shield half 5
4 [54a, 54b] and a plate-like inner beam shield half 56 [56a, 56b] along the short side magnetic shield half 54 [54a, 54b] is integrally formed. Body 56 [56a, 56
b) is formed in a fan shape so that the inner beam shield halves 56a and 56b are perpendicular to the long sides during bending.

Magnetic shield portion 5 to be a long side slope
3 has a trapezoidal shape with the electron gun side as the upper bottom. The magnetic shield half 54 [54a, 54] which becomes the slope portion on the short side side
b] has a triangular shape except for the welding margin 57 at the end. Skirts 58 and 59 extending from the lower bottom thereof are formed in the trapezoidal magnetic shield portion 53 on the long side.
Also, the inner beam shield half 54 [54a, 54
The skirt portion 60 is also formed in FIG. Skirt part 5
Reference numeral 8 denotes a welding attachment member that is welded to the frame 45 of the color selection mechanism 45, that is, the support members 41 and 42 thereof.

The inner magnetic shield forming member 52 is formed substantially symmetrically with respect to the center line on the long side,
Only the inner beam shield half 56a on one side is integrally formed with a frame of the color selection mechanism 45, that is, a welding attachment portion 61 to which the STC plate surface 48 of the elasticity providing members 43 and 44 is welded. A welding margin 62 is formed at the ends of the two inner beam shield halves 56a and 56b.

Further, the short side magnetic shield halves 54a and 54b of the other inner beam shield half 56b
On the opposite side, the completed internal magnetic shield structure 50
When a plurality of are stacked and stored, a sticking prevention part 64 for preventing sticking to each other is provided integrally.
The sticking prevention portion 64 is formed by turning twice at the positions of the two bending lines m ₁ and m ₂ (see FIG. 7). In FIG. 5, the bending line m ₁ is a line that folds into a mountain shape, and the bending line m ₁ is a line that folds into a valley (see FIG. 3).

Next, the manufacture of the internal magnetic shield structure 50 will be described. Internal magnetic shield forming member 52 shown in FIG.
Are prepared. Two internal magnetic shield forming members 5
2 [52A, 52B] are bent at bending lines m ₁ and m ₂ , for example, by press working or the like. The fan-shaped bent portions 72 of the inner beam shield halves 56a and 56b are bent so as to narrow the four bending lines m ₁ and m ₂ . Thereby, the inner beam shield halves 56a and 56b are bent at right angles to the long side. Short side magnetic shield halves 54a, 54b
Is also bent such that the bottom side is at right angles to the long side (see FIG. 6).

Next, as shown in FIG. 3, the two inner magnetic shield forming members 52A and 52B which have been bent are connected to the respective short side magnetic shield halves 54a and 54b by the inner beam shield halves 56a. And 56b are welded together in a state where they are overlapped with each other. At this time, the inner beam shield halves 56a and 56b are overlapped upside down on both short sides as shown in FIGS. That is, one inner beam shield half 56a of the first internal magnetic shield forming member 52A is connected to the second internal magnetic shield forming member 52A.
B, the first inner magnetic shield forming member 52A is superposed above the other inner beam shield half 54b.
The other inner beam shield half 56b is overlapped below one inner beam shield half 54a of the second internal magnetic shield forming member 52B. on the other hand,
On the side of the inner beam shield half 56 side, a sticking prevention part 64 bent downward in an L-shape by bending along the bending lines m ₁ and m ₂ is formed. In this way,
As shown in FIG. 3, a target internal magnetic shield structure 50 including a long side magnetic shield portion 53, a short side magnetic shield portion 66, and an inner beam shield portion 67 is obtained.

When the internal magnetic shield structure 50 is mounted on the color selection mechanism 37, the internal magnetic shield structure 50
Is welded to the STC plate 48 on the lower surface of the elasticity imparting members 43 and 44 of the frame 45, and the skirt portion on the long side of the internal magnetic shield structure 50, that is, the welding attachment portion 58 is Forty-five support members 41 and 42 are welded to the side surfaces and integrated.

According to the above-described embodiment, the two internal magnetic shield forming members 52 having the same structure shown in FIG.
One internal magnetic shield structure 50 can be formed. Accordingly, the number of components of the internal magnetic shield structure 50 can be reduced from three in the related art to two.
The individual components may be the same components, and the inner magnetic shield assembly 50 can be manufactured with substantially one type of component. The internal magnetic shield forming member 52 includes a long side magnetic shield portion 53, a short side magnetic shield half 54 [54a, 54b] and an inner beam shield half 56 continuous to one and the other side thereof. [56a, 56b] are formed in a substantially U-shape, and the whole is made compact, so that waste of material is reduced. Only one type of mold is needed to form the components. Therefore, it is possible to reduce the number of plate materials, the number of parts, the number of required molds, the number of assembling steps, the number of man-hours, and the like, thereby reducing the manufacturing cost.

Further, the internal magnetic shield structure 50
Is structurally unchanged. Therefore, the cathode ray tube 31 provided with the internal magnetic shield structure 50 can shield a horizontal overscan unnecessary electron beam,
Further, the cost can be reduced without deteriorating the geomagnetic shield characteristics.

When a plurality of internal magnetic shield assemblies 50 are stacked for storage, transportation, etc., as shown in FIG.
The sticking prevention portion 64 prevents the upper and lower internal magnetic shield structures 50 from sticking, and facilitates subsequent handling. Here, as shown in FIG. 4 and FIG. 7, when the inner magnetic shield structures 50 are stacked, the welded attachment portion 61 and the bent portion 71 sandwiching the welded attachment portion 61 are folded with a required inclination. To sing. And
Fig. 7
It is desirable to reduce the upper and lower gap d in the stacked state shown in FIG. However, if the gap d is too small,
Biting occurs and it is difficult to separate. The gap d is 2 to 7
mm, preferably about 5 mm.

[0030]

According to the internal magnetic shield forming member of the present invention, one internal magnetic shield structure can be formed by two internal magnetic shield forming members having the same shape. The number of the members for forming the internal magnetic shield required to obtain the above can be made smaller than the conventional three members. The two internal magnetic shield forming members are:
Since the same shape may be used, only one mold is required. Further, the shape of the member for forming the internal magnetic shield is such that the short-side magnetic shield half extends on both sides of the long-side magnetic shield portion at a predetermined inclination angle with respect to the long side via the bent portions respectively. Since the inner half of the inner beam shield is formed into a compact substantially U-shape, the waste of the plate material in press punching can be reduced. Therefore, the manufacturing cost of the internal magnetic shield structure can be reduced.

According to the internal magnetic shield structure of the present invention, since it is composed of two internal magnetic shield forming members having the same shape, the cost can be reduced. In addition, since it has a magnetic shield portion and an inner beam shield portion in terms of structure, the cost can be reduced while maintaining the same terrestrial magnetism shield characteristics and shield characteristics of a horizontal overscan unnecessary electron beam as in the related art. Therefore,
It is suitable for application to a cathode ray tube.

According to the method of manufacturing the internal magnetic shield structure according to the present invention, two internal magnetic shield forming members having the same shape are prepared, and the short side magnetic shield halves and the inner beam shield halves are connected. Since they are connected and manufactured, only one type of molding die is required for the member for forming the internal magnetic shield, and the number of materials (the number of parts), material waste, assembly man-hours, and the like can be reduced. Further, the internal magnetic shield forming member can be easily handled at the time of assembly, and the assembly can be facilitated. Therefore, manufacturing costs can be reduced.

According to the cathode ray tube of the present invention, since the internal magnetic shield structure is provided, the electron beam unnecessary for overscan in the horizontal direction is shielded, and the cost is reduced without deteriorating the terrestrial magnetism shield characteristics. Can be.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of a cathode ray tube according to the present invention.

FIG. 2 is an exploded perspective view of the cathode ray tube of FIG.

FIG. 3 is a perspective view showing an embodiment of the internal magnetic shield structure according to the present invention.

FIG. 4 is a perspective view of a main part of the internal magnetic shield structure of FIG. 3 as viewed from the opposite side.

FIG. 5 is a development view showing an embodiment of a member for forming an internal magnetic shield according to the present invention.

FIG. 6 is an exploded perspective view of the internal magnetic shield structure of FIG. 3;

7 is a cross-sectional view of a main part in a state where a plurality of the internal magnetic shield structures of FIG. 3 are stacked.

FIG. 8 is a development view of a conventional member for forming an internal magnetic shield.

FIG. 9 is a perspective view of a conventional internal magnetic shield structure.

FIG. 10 is an exploded perspective view of a conventional cathode ray tube having an internal magnetic shield structure.

[Explanation of symbols]

31 ... Cathode tube, 36 ... Fluorescent screen, 37 ... Color selection mechanism, 38 ... Electron gun, 41, 42 ... Support member, 43, 44 ... Elasticity imparting member, 45 ... ..Frame, 46 ... Color selection electrode thin plate, 50 ... Inner magnetic shield structure, 52 [52A, 52B ... Inner magnetic shield forming member, 53 ... Long side magnetic shield portion, 54 [54a, 54b] ··· short side magnetic shield half, 56 [56a, 56b] ··· inner beam shield half, 58, 61 ··· welding attachment part, 66 ·
... short side magnetic shield part, 71, 72 ... bent part, m _1, m ₂ ... folding line.

Claims (4)

[Claims] 1. A short side extending at a predetermined inclination angle with respect to the long side via a bent portion on one side and the other side of a plate-shaped long side magnetic shield part which is a slope on the long side. A plate-shaped short side magnetic shield half which is a slope on the side,
A plate-shaped inner beam shield half is formed integrally with the short side magnetic shield half, and a bent portion of the inner beam shield half is formed by bending the inner beam shield half with respect to the long side during bending. A member for forming an internal magnetic shield, wherein the member is formed in a fan shape so as to form a right angle. 2. A short side extending at a predetermined inclination angle with respect to the long side through a bent portion on one side and the other side of a plate-shaped long side magnetic shield part serving as a long side slope. A plate-shaped short side magnetic shield half which is a slope on the side,
A plate-shaped inner beam shield half is formed integrally with the short side magnetic shield half, and a bent portion of the inner beam shield half is formed into a fan shape. An internal magnetic shield structure, wherein the two internal magnetic shield forming members are respectively bent and connected to each other by short side magnetic shield halves and inner beam shield halves. 3. A short side extending at a predetermined inclination angle with respect to the long side via a bent portion on one side and the other side of a plate-shaped long side magnetic shield portion serving as a long side slope. A plate-shaped short side magnetic shield half which is a slope on the side,
A plate-like inner magnetic shield half along the short side magnetic shield half is integrally formed, and two inner magnetic shield forming members each formed by bending a bent portion of the inner beam shield half into a fan shape. Prepared, each of the internal magnetic shield forming members is bent to form the long side magnetic shield portion and the short side magnetic shield half as an inclined surface portion, and each of the inner beam shield halves with respect to the long side. Forming an inner magnetic shield assembly by connecting the two inner magnetic shield forming members to each other with short side magnetic shield halves and inner beam shield halves. A method for manufacturing a magnetic shield structure. 4. A cathode ray tube comprising the internal magnetic shield structure according to claim 2.