JPS5918825B2 - cathode ray tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a color cathode ray tube, and particularly to a color cathode ray tube in which mislanding of an electron beam due to thermal deformation of a color selection electrode, that is, a grid device during operation, is avoided by mechanical means in the grid device. That is.

First, the grid device used in this invention will be explained with reference to FIG. 2. This grid device G consists of a pair of support rods 1 and 2 arranged parallel to each other at a predetermined interval; A ribbon-shaped frame 5 is mounted on a window-frame-shaped frame 5 consisting of elastic supports 3 and 4 attached between the Bessel points of the support rods 1 and 2 or in the vicinity thereof. It is constructed by stretching grid elements 6 at a predetermined pitch, and is mainly used as a so-called Trinitron (registered trademark) type color cathode ray grid device.

This grid device G normally consists of one support rod 1 and elastic holding members 7 attached to both elastic supports 3 and 4, respectively.
, 8 and 9, i.e. each holding member? , 8 and 9 are fitted into stud pins 11, 12, and 13 integrally protruding from the inner surface of the panel, respectively, to be mounted in the panel 10 of the cathode ray tube with so-called three-point support. .

By the way, in a color cathode ray tube using such a grid device G, during its operation, the grid element body 6 generates heat due to the collision of the electron beam, and the heat is transmitted to the frame 5, which thermally expands, thereby causing the electron beam to emit light. A mislanding occurs.

That is, as shown in FIG. 1, when the support rods 1 and 2 thermally expand in the longitudinal direction due to the thermal influence of the frame 5, the grid element body 6 also displaces following this, and therefore the grid element body 6 especially in the peripheral area The slit 14 is displaced (state shown by dotted lines).

For this reason, it passes through an arbitrary slit 14 at the position A1 when no thermal expansion occurs and reaches a predetermined position P on the fluorescent surface 15.
After the beam 16 reaches the point where the support rods 1 and 2 are thermally deformed,
As shown by the dotted line 16', the slit 1 is displaced to the position <A2.
4 and reaches the position P2 of the fluorescent surface 15, resulting in a mislanding.

In view of the above-mentioned points, the present invention mechanically compensates for thermal deformation of the grid device frame, particularly its support rod, to minimize mislanding in the peripheral area. The company provides cathode ray tubes.

Hereinafter, the present invention will be explained in detail using FIG. 3 and subsequent figures.

FIG. 4 shows an example of a grid device according to the present invention, and numeral 5 in the figure indicates a window frame-like frame having the same configuration as that explained in FIG. Ta1
It is composed of a pair of support rods 1 and 2, and approximately U-shaped elastic supports 3 and 4 attached between both support rods 1 and 2. A large number of ribbon-like grid elements 6 are stretched at a predetermined pitch so as to be spanned between the two.

In the present invention, the thermal expansion coefficients of the support rods 1 and 2 are attached to the surface opposite to the surface on which the grid element 6 is stretched with respect to the pair of support rods 1 and 2 constituting the frame 5. The large metal bodies 1γ and 18 are fixed together by welding or other means, and as the temperature of the frame 5 rises, the support rods 1 and 2
When the metal bodies 17 and 18 thermally expand in the longitudinal direction, the support rods 1 and 2 are curved toward the fluorescent surface side due to the difference in thermal expansion coefficient between the metal bodies 17 and 18 and the support rods 1 and 2.

The metal bodies 17 and 18 may be selected from various materials depending on the material of the frame 5. For example, if the frame 5 is made of iron, it may be made of industrial standard 5US-27 material.

Further, each of the metal bodies 17 and 18 can be formed to have a U-shaped cross section, for example, in order to be lightweight and maintain mechanical strength.

Holding members 19, 20, 21 and 22 are attached to each of the support rods 1 and 2 of the frame 5 and the elastic support body 3. The thus constructed grid device is mounted on the inner surface of the cathode ray tube panel 10 by so-called four-point support.

The valley holding members 19, 20, 21, and 22 can have the same configuration, for example, support rods 1, 2, respectively.
and pedestals 23, 24 directly welded to the elastic supports 3, 4,
25 and 26, and elastic support pieces 27, 28, made of, for example, plate springs, welded to the respective pedestals 23, 24, 25, and 26.
29 and 30, each elastic support piece 27, 2
8, 29 and 30 have stud pins 3 on the panel side.
For example, triangular through holes 35 are provided which engage with L32, 33 and 34.

Holding members 19 and 20 facing each other, and holding member 2
1 and 22 are fixed in a line-symmetrical relationship with respect to the frame 5, respectively.

Here, holding members 19 and 2 attached to support rods 1 and 2
0, the through holes 35 of the elastic support pieces 21 and 28
In order to form the pedestals 23 and 24 so as to be located at the center of the frame 5, the welding centers of the pedestals 23 and 24 to the support rods 1 and 2, respectively, are shifted from the center of the frame 5.

In the present invention, the frame 5 is thermally influenced so that when the support rods 1 and 2 are each curvedly displaced toward the fluorescent surface side, the amount of displacement at both ends of the support rods 1 and 2 is equal. Support rod 1 of holding members 21 and 22 of both elastic supports 3 and 4
, 2 are made to differ from each other.

That is, in the case of FIGS. 4 and 5, the elastic support 3
and elastic support pieces 2 of holding members 21 and 22 attached to 4.
The spring strengths of the cathode ray tubes 9 and 30 in the direction along the tube axis ζ are made different from each other.

Here, as described above, the welding centers of the pedestals 23 and 24 of the holding members 19 and 20 to the support rods 1 and 2 are offset from the center of the frame 5.

For this reason, the elastic support pieces 29 and 3 of the elastic supports 3 and 4
If the spring strengths in the direction along the tube axis of 0 are equal to each other, when the frame 5 is subjected to thermal influence, the support rods 1 and 2 will each move toward the frame center Y, as shown in FIG.

The left and right sides of the pedestals 23 and 24 which are shifted from each other undergo a curved displacement about the welding center Y1 as a fulcrum, and the displacement amounts X1 and X2 at both ends are different from each other.

If the welding center Y1 is shifted to the left, the displacement X1 on the left side will be large and the displacement X2 on the right side will be small with the welding center as a fulcrum, as shown in FIG.

Therefore, in the present invention, the displacement amounts X1 and X2 at both ends are made equal, and the apparent frame center Y is set.

In order to displace the support rod 1.2 in a well-balanced left-right direction using the support rod 1.2 as a fulcrum, the spring strength in the tube axis direction of the elastic support piece 30 of the holding member 22 attached to the elastic support 4 is strengthened, and the elastic support 3 is attached as shown in FIG. The spring strength of the elastic support piece 29 of the holding member 21 in the tube axis direction is weakened.

The spring strength of the elastic support pieces 29 and 30 in the tube axis direction can be determined by selecting the width l as shown in FIG. The larger the size, the stronger the spring strength.

In this case, the spring strength of the holding members 21 and 22 and the bimetallic structure formed by the metal bodies 17 and 18 are such that, as shown in FIG. When thermally expanded, the slit 14 is simultaneously displaced to the state shown by the dotted line, that is, when any slit 14 in the periphery of the grid element 6 is displaced from position A1 to position A2 due to thermal expansion, that slit 14 further thermally expands. Position A on the trajectory of the beam 16 passing through the previous slit 14
Select the shape, material, etc. so that the displacement is 3.

According to the above-mentioned configuration, when the frame 5 thermally expands due to thermal influence, the thermal expansion coefficient of the pair of opposing support rods 1 and 2 with respect to the metal bodies 17 and 18 fixed thereto is the same. The difference causes a curved displacement as shown by the dotted line in FIG. 3, and the grid element body 6 is uniformly displaced toward the fluorescent surface side.

Moreover, in this case, the welding center Y of the holding members 19 and 20 with the pedestals 23 and 24, which is the center of curvature of both the support rods 1 and 2.
1 is the frame center Y.

Although the elastic support pieces 29 and 3 of the left and right holding members 21 and 22 that support the elastic supports 3 and 4 are deviated from each other,
The spring strength in the direction along the tube axis of 0 (spring strength in the direction shown by the dotted line in FIG. 7) is made different, that is, in the examples of FIGS. 4 and 5, the spring strength on the elastic support 4 side is made different. Since the spring strength on the side of the elastic support body 3 is made weak, the displacement amounts X1 and X2 on the left and right sides of the support rods 1 and 2 are equal, and the grid element 6 is displaced toward the fluorescent surface side with a uniform displacement amount on the left and right sides. However, mislanding of the beam can be minimized as much as possible.

In the configuration shown in FIG. 3, the through holes 35 of the elastic support pieces attached to the support rods 1 and 2 are of course formed so as to be centered on the frame, but at the same time, the welding center of the pedestal 23t24 during thermal expansion is formed. The difference in the amount of displacement between the left and right sides of the support rods 1 and 2 used as fulcrums (the difference in displacement amount X1-x2 when the spring strengths of the holding members 21 and 22 are made equal to each other) is made as small as possible, and the left and right holding members 21 The support rods 1 of the pedestals 23 and 24 are designed to reduce the difference in spring strength in the direction along the tube axis of the pedestals 23 and 22, and to balance the mechanical strength of both the holding members 21 and 22.
It is possible to bring the welding center for 2 and 2 as close as possible to the center of the frame.

Specifically, the frame center Y as shown in FIG.

and the welding center Y1 of the pedestals 23 and 24 to the support rods 1 and 2. d1 The distance from one end of the frame 5 to the center Y.

The welding center is selected at a position that satisfies i<o, 2, preferably at a position where the distance d is within 15 mm, where D is the distance to the center.

FIG. 8 shows an embodiment for this purpose, in which a pedestal 36 in the form of an abbreviation is provided, one end of which is welded to a position Y close to the frame center of the support rods 1 and 2, and an elastic support piece at the other end. The base portions 29 and 30 are welded, respectively.

According to this configuration, the elastic support pieces 29 and 30 have a predetermined length that provides appropriate spring properties, and the pedestal 2
The welding centers of Nos. 3 and 24 can be moved closer to the center of the frame.

Next, a mounting method for mounting the grid device on a cathode ray tube panel with four-point support as in the present invention will be described with reference to FIGS. 11 to 14.

Normally, it is easy to install a grid device with three-point support, but in the case of four-point support, it is difficult to install the grid device if stud pins and holding members are attached in advance at four locations.

This is due to the alignment accuracy between the stud pin and the holding member, and in the case of four positions, no error is allowed.

To this end, in the present invention, as shown in FIG. 11, stud pins 31, 33, and
Install 4.

On the other hand, in the grid device, the stud pin 31.33
and 34, one support rod 1 and both elastic supports 3 and 4 are provided with ordinary holding members 19, 21 and 22 consisting of a pedestal as shown in FIG. 4 and an elastic support piece of a predetermined length.
At the same time, a tongue-shaped holding member 37 is attached to the center of the other support rod 2, as shown in FIG.

A portion of this tongue-shaped holding member 37 is welded to the center of the support rod 2, and the free end provided with the through hole 35 comes into elastic contact with the inner surface of the panel when the grid device is inserted into the panel 10. It has an outwardly bent shape.

In the manufacturing process of color cathode ray tubes, there is a step of forming a color fluorescent surface using a grid device as an optical mask.

Therefore, when attaching the grid device when forming a color fluorescent surface on the inner surface of the panel, as shown in FIG.
9, 21 and 22 respectively with three stud pins 31.3
3 and 34 to temporarily hold the grid device with three-point support.

With three-point support, the grid device can be easily attached and detached, and the fluorescent surface can be easily formed.

Next, after forming the fluorescent surface, a grid device is attached with four-point support.

That is, while the grid device is held in the panel with three-point support, the fourth stud pin 32 is inserted through the through hole 35 of the tongue-shaped holding member 37 as shown in FIG. ) 38 to the inner surface of the panel 10.

Since this stud pin 32 is fixed to the inner surface of the panel with the grid device attached, it is necessary to use the cement 38 so that it can be fixed at room temperature.For this purpose, the cement may be water glass, forsterite, alumina, etc. A material containing a filler is used.

With this mounting method, the grid device can be supported at exactly four locations.

FIGS. 15 to 1T show other examples of the present invention.

Instead of making the spring strengths of the holding members 21 and 22 of the elastic supports 3 and 4 different from each other, a bimetallic structure is constructed by using a normal holding member for one and the elastic support for the other. This is a case in which the amount of left and right deformation of the support rods 1 and 2 is controlled on the one hand by the spring strength of the holding member, and on the other hand by the amount of bimetallic deformation of the deformation holding member.

That is, as shown in FIG. 15, a holding member 22 as shown in FIG. 4 is attached to one of the elastic supports 3 and 4, for example, the elastic support 4, and the other elastic support 3 is deformed and held. Member 39 is used.

In this case, the deformable holding member 39 may be provided on either of the elastic supports, but when considering the mechanical strength of the holding member, it may be provided on the side of the elastic support whose spring strength is weakened as described above.

As shown in FIG. 16, this deformation holding member 39 is made of a metal having a larger coefficient of thermal expansion than the elastic support 3, and includes a mountain-shaped strip plate 40 bent from the center, and the strip plate 40.
It consists of an elastic support piece 41 that extends along the elastic support body 3 from one side of the mountain shape of 0 and has a through hole 35 at its free end that engages with a stud pin. It is configured by being fixed to the surface of the support 3 opposite to the fluorescent surface side.

According to the deformation holding member 39, when the frame 5 thermally expands, the band-like plate body 40 also expands and deforms, and at this time, the free end of the elastic support piece 41 is connected to the through hole 35 and the stud pin 3.
3, the elastic support 3 moves toward the fluorescent surface as shown by dotted lines in FIGS. 17A and 17B.

Therefore, according to the configuration shown in FIG. 15, when the frame 5 is affected by heat, the support rods 1 and 2 are displaced from the center of the frame due to the difference in thermal expansion with the metal bodies 17 and 18;
That is, although each of the holding members 19 and 20 curves around the center of welding with the pedestal as a fulcrum, at this time, the elastic strength of the holding member 22 on the side closer to the welding center in the tube axis direction is strong, so that the support rods 1 and 2 are elastically supported. While suppressing the amount of displacement of the portions extending toward the body 4 side, the portions of the support rods 1 and 2 extending toward the elastic support body 3 are made to have a predetermined amount of displacement by deforming the band-shaped plate 40 of the deformation holding member 39. Therefore, the amounts of left and right displacement of the support rods 1 and 2 become equal, and the grid element body 6 is uniformly displaced toward the fluorescent surface side as shown by the dotted line in FIG. 4, thereby avoiding mislanding of the beam.

In each of the above-mentioned embodiments, as shown in FIG. 10, a notch 42 is provided at the center of the support rods 1 and 2, and metal bodies 17 and 18 with sufficient strength are mounted across the notch 42. It can also be configured.

When the notches 42 are provided in this way, the bending action of the support rods 1 and 2 toward the fluorescent surface side becomes easy, so the size of the metal bodies 17 and 18 can be reduced, and therefore, it is possible to reduce the size of the metal bodies 17 and 18. It is suitable when applied.

As described above, according to the present invention, when the frame of the grid device undergoes thermal deformation, it is mechanically displaced and the grid element body is moved toward the fluorescent surface side, and the displacement at that time is in the left and right directions. Since this is done in a well-balanced manner, mislanding of the beam during operation can be avoided.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the state of mislanding used to explain the present invention, FIG. 2 is a plan view showing an example of a conventional grid device, FIG. 3 is a diagram showing the operating state of the present invention, and FIG. The figure is a perspective view showing an example of the grid device according to the present invention.
The figure shows a state in which this grid device is attached to the panel of a cathode ray tube, FIG. 6 shows a state in which the frame is thermally deformed to explain the present invention, and FIG. 7 is a perspective view of the main parts of the holding member used in the present invention. , FIG. 8 is a perspective view showing another example of the holding member, FIG. 9 is a side view showing another example of the grid device of the present invention, and FIG.
11 is a plan view showing a method of mounting the grid device of the present invention on the inner surface of a panel; and FIG. 12 is a perspective view of the main parts of the grid device of the present invention. 13 and 14 are process diagrams, FIG. 15 is a plan view showing still another example of the present invention, FIG. 16 is a perspective view showing an example of the deformation holding member, and FIG. 17 A and B are operation state diagrams of the deformation holding member. 1 and 2 are support rods, 3 and 4 are elastic supports, 5 is a frame,
6 is a grid element body, 17 and 18 are metal bodies having a large coefficient of thermal expansion, 19, 20, 21, and 22 are holding members, and 39 is a deformation holding member.

Claims (1)

[Claims] 1. A large number of ribbon-shaped grid elements are stretched over a frame consisting of a pair of opposing support rods and a pair of elastic supports attached between the support rods, and the grid elements of the support rods are Grid devices each having a metal body having a coefficient of thermal expansion larger than that of the support rods are fixed to the surface opposite to the stretching surface of the cathode ray tube panel at four locations on the support rods and the elastic supports. The support rod is held through an attached holding member, and the force acting on the support rod during thermal expansion of each holding member attached to both elastic supports is balanced so that the displacement amount at both ends of the support rod is equal. A cathode ray tube consisting of different types.