JP3346909B2 - Color picture tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color picture tube, and more particularly to a color picture tube in which the contact of a contact spring attached to a shadow mask to an inner conductive film formed on an inner surface of a funnel is stabilized.

[0002]

2. Description of the Related Art Generally, a color picture tube has an envelope comprising a panel 1 and a funnel 2 having a funnel shape, as shown in FIG. A phosphor screen 4 made of a phosphor layer and having a metal back layer 3 formed on the back surface is provided. A shadow mask 5 is mounted inside the phosphor screen 4 so as to face the phosphor screen 4. The shadow mask 5 includes a mask body 6 having a large number of electron beam passage holes formed therein and a mask frame 7 attached to a peripheral portion of the mask body 6. The panel 1 is supported inside the panel 1 by engaging with a stud pin 9 provided on the panel 1. Further, an internal magnetic shield 11 located inside the large-diameter portion 10 of the funnel 2 is attached to the mask frame 7 of the shadow mask 5. On the other hand, an electron gun 13 for emitting three electron beams is disposed in a neck 12 of the funnel 2. An anode terminal 14 is provided on the large diameter portion 10 of the funnel 2. Further, from the large diameter portion 10 of the funnel 2 to the inner surface adjacent to the neck 12, an inner conductive film 15 mainly composed of graphite particles is applied and formed. Furthermore, one or a plurality of contact springs 17 that are electrically connected to the inner conductive film 15 on the inner surface of the large-diameter portion 10 of the funnel 2 are attached to the mask frame 7 of the shadow mask 5.

The contact spring 17 guides a high voltage supplied to the anode terminal 14 to the shadow mask 5 via the inner conductive film 15, and is provided on the frame holder 8 attached to the mask frame 7 and the panel 1. This is for guiding the phosphor screen 4 through the stud pins 9 and the like, and is formed from an elastic material into the shape shown in FIG. That is, the contact spring 17 includes a fixing portion 18 fixed to the mask frame 6,
A spring portion 19 that is bent from the fixed portion 18 and extends at a predetermined bending angle, and is provided at the tip of the spring portion 19 and presses against the inner conductive film 15 on the inner surface of the large-diameter portion 10 of the funnel 2. And a spherical pressure contact portion 20.
This conventional contact spring 17 is used for the inner conductive film 1.
For the purpose of stabilizing the contact with the spring 5, the spring portion 19 is divided into two by a notch groove 21 reaching the fixing portion 18 from the front end portion provided at the center, and each of the split spring portions 19a and 19b is further divided. Notch grooves 22a and 22b shorter than the central notch groove 21 are formed on the tip end side, and have four press-contact portions 20 separated by these central notch grooves 21, 22a and 22b. The four pressure contact portions 20 are formed in a structure in which the four pressure contact portions 20 are pressed against the inner surface conductive film 15 mainly by the elasticity of the spring portion 19.

[0004]

As described above, the color picture tube uses the inner conductive film provided on the inner surface of the large-diameter funnel to supply the high voltage supplied to the anode terminal provided on the large-diameter portion of the funnel. A contact spring for electrically connecting the shadow mask and the inner conductive film is mounted on a mask frame of the shadow mask in order to guide the shadow mask and the phosphor screen through the mask. The contact spring is formed of an elastic material and fixed to the mask frame, a spring portion bent from the fixed portion and extending at a predetermined bending angle, and provided at a tip of the spring portion. It consists of a spherical press-contact portion that presses against the inner conductive film on the inner surface of the large-diameter portion of the funnel, and the spring portion is almost fixed from the tip provided at the center for the purpose of stability of contact with the inner conductive film. The two notches are formed by a notch groove reaching the portion, and a notch groove shorter than the center notch groove is formed at the tip end side of each of the split spring portions. The four notches are separated by these notch grooves. Are formed in a structure in which these four pressed portions are pressed against the inner surface conductive film.

However, even if a plurality of the contact springs are attached to the mask frame, a sufficiently stable contact with the inner conductive film cannot be obtained, resulting in poor contact. In addition, contact failure occurs temporarily due to external shock or vibration,
Due to the resulting reverse voltage, there is a problem that the metal back layer on the back surface of the phosphor screen is peeled off, the withstand voltage is deteriorated, and an image defect is easily generated due to emission of electrons from the dropped inner conductive film piece.

As a method of solving the problem of the contact spring, a method of strengthening the contact pressure against the inner conductive film without forming a notch groove in the spring portion can be considered. The pressure becomes too strong, and the detachment of the inner conductive film piece increases. Therefore, if the width of the spring portion is reduced to weaken the contact pressure of the contact spring with respect to the inner conductive film, the pressure contact with the inner conductive film becomes unstable, and the same failure occurs.

In a conventional contact spring, if all of the plurality of notch grooves in the spring portion are formed to be long, the spring portion resonates in a specific vibration mode,
There is a problem that the amplitude of the press-contact portion increases.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is intended to improve the contact of a contact spring with an inner conductive film formed on the inner surface of a large-diameter portion of a funnel so that the contact spring and the inner conductive film can be contacted. An object of the present invention is to obtain a color picture tube that stabilizes an electrical connection with a film.

[0009]

A mask frame is attached to the periphery of a mask body, and a shadow mask mounted inside a panel of an envelope including a panel and a funnel, and an inner conductive surface formed on an inner surface of the funnel. A contact spring for electrically connecting the film, the shadow mask and the inner conductive film, the contact spring being fixed to the mask frame, a spring extending from the fixation, The contact spring is formed in a structure having a plurality of apertures at positions close to the pressure contact portion of the spring portion, in a color picture tube comprising a plurality of pressure contact portions provided at the tip of the portion and pressed against the inner surface conductive film. did.

[0010]

As described above, when the contact spring is formed in a structure having a plurality of openings near the press contact portion of the spring portion, the contact pressure of the plurality of press contact portions against the inner conductive film is made uniform, and The contact with the conductive film becomes stable. Therefore, the temporary contact failure which has conventionally occurred when an external impact, vibration, or the like is applied is eliminated, and the deterioration of the withstand voltage, the detachment of the inner conductive film piece, and the like can be reduced.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings based on embodiments.

FIG. 1 shows the structure of a main part of a color picture tube as one embodiment. Since the overall structure of this color picture tube is substantially the same as that of a conventional color picture tube, it will be described below with reference to FIG. 1 and FIG.

This color picture tube has an envelope composed of a panel 1 and a funnel 2 having a funnel shape.
Is provided with a phosphor screen 4 composed of a three-color phosphor layer in the form of dots or stripes that emit blue, green, and red light. This phosphor screen 4 is provided with a metal back layer 3 on the back surface, and is a metal back phosphor screen. Further, a shadow mask 5 is mounted inside the phosphor screen 4 so as to face the phosphor screen 4.
The shadow mask 5 includes a mask body 6 having a large number of electron beam passage holes formed therein and a mask frame 7 attached to a peripheral portion of the mask body 6. Panel 1
Are supported on the inside of the panel 1 by engaging with stud pins 9 provided on the panel 1. Further, a large diameter portion 1 of the funnel 2 is provided on the mask frame 7 of the shadow mask 5.
The inside magnetic shield 11 located inside the inside of the housing is attached. On the other hand, an electron gun 13 for emitting three electron beams is disposed in a neck 12 of the funnel 2. An anode terminal 14 is provided on the large diameter portion 10 of the funnel 2. Further, from the large diameter portion 10 of the funnel 2 to the inner surface adjacent to the neck 12, an inner conductive film 15 mainly composed of graphite particles is applied and formed. Furthermore, the above-mentioned shadow mask 5
As shown in FIG. 1A, one or a plurality of contact springs 30 electrically connected to the inner conductive film 15 on the inner surface of the large-diameter portion 10 of the funnel 2 are attached to the mask frame 7 described above. .

The contact spring 30 guides a high voltage supplied to the anode terminal 14 to the shadow mask 5 via the inner conductive film 15, and is provided on the frame holder 8 attached to the mask frame 7 and the panel 1. This is for guiding the phosphor screen 4 through the stud pins 9 and the like, and is made of an elastic material and formed in the shape shown in FIG. That is, the contact spring 30 includes a fixing portion 31 fixed to the mask frame 6, a spring portion 32 bent from the fixing portion 31 and extending at a predetermined bending angle, and a tip portion of the spring portion 32. , The large diameter portion 10 of the funnel 2
It comprises four spherical pressure-contact portions 33 that press against the inner conductive film 15 on the inner surface.

In particular, in the contact spring 30 of this example, a non-opening portion 35 having a constant width d is left in a position close to the press contact portion 33 in the spring portion 32, and has substantially the same size with the major axis in the longitudinal direction of the spring portion 32. 3 holes 36
Are formed in parallel in the width direction of the spring portion 32, and further, at the central portion between the three openings 36 and the fixing portion 31, one opening 37 having a major axis in the longitudinal direction of the spring portion 32 is also provided. Is formed.

When the contact spring 30 is configured as described above, the four press contact portions 33 are integrally connected by the non-opening portions 35 having a constant width d provided between the four press contact portions 33 and the three opening holes 35. Because of the structure, the elasticity of the spring portion 32 allows each press contact portion 33 to uniformly contact the inner conductive film 15, and the inner conductive film 15 on the inner surface of the funnel 2.
Can be stabilized. Moreover, by adjusting the size of the three openings 36 and the openings 37 of the spring portion 32, the spring constant of the spring portion 32 is optimized, and the contact pressure of each press contact portion 33 with the inner conductive film 15 is reduced. By optimizing, a highly reliable and high quality color picture tube can be obtained.

As a practical test, a color picture tube to which the above-mentioned contact spring 30 was attached was assembled into a TV set.
0.5mm amplitude, 10Hz to 55Hz to 10Hz frequency
The vibration test was performed in addition to three directions (X, Y, Z directions) orthogonal to each other for 5 cycles by sequentially changing
As a result of comparison with a conventional color picture tube having a contact spring attached thereto, in the conventional color picture tube, the inner conductive film having a diameter of 3.0 mm was peeled off at four places due to the contact of the contact spring. In the color picture tube to which the contact spring 30 is attached, the peeling of the inner conductive film 15 due to the contact with the contact spring 30 occurred at four places. It has been shown that 30 welds are improved. The color picture tube to which the contact spring 30 of this example was attached had no problem in withstand voltage after the vibration test.

As described above, in the contact spring 30 of this embodiment, the contact of each press-contact portion 33 with the inner conductive film 15 becomes uniform and stable, and the amplitude of each press-contact portion 33 is increased even when an external impact or vibration is applied. Highly reliable, high-quality color picture tube that can be made smaller, eliminates temporary contact failures caused by external shocks and vibrations, reduces degradation of withstand voltage, and detachment of inner conductive film pieces. Can be configured.

Next, another embodiment will be described.

The contact spring shown in FIG. 2 includes a fixing portion 31 fixed to the mask frame, and the fixing portion 31.
Spring portion 32 which is bent at a predetermined bending angle and is provided with five spherical press-contact portions 33 which press the front end portion of the spring portion 32 against the inner conductive film on the inner surface of the large-diameter portion of the funnel. And leaving a non-opening portion 35 having a constant width d at a position close to the press contact portion 33 in the spring portion 32,
Three apertures 36 of substantially the same size having the major axis in the longitudinal direction of the spring portion 32 are formed in parallel in the width direction of the spring portion 32, and further, between the three apertures 36 and the fixing portion 31, Similarly, the longitudinal direction of the spring portion 32 is defined as a major axis 3
The openings 37 are formed in parallel in the width direction of the spring portion 32.

When the three openings 36 and 37 are formed in the spring portion 32 in this manner, the spring portion 32 can have a different spring constant from the contact spring of the above embodiment. Thereby, the spring constant of the spring portion 32 can be optimized, and the contact pressure of each press contact portion 33 with the inner conductive film can be made uniform and stabilized, so that a contact spring having the same effect as the above embodiment can be obtained. it can.

In the above embodiment, four press contact portions are provided at the tip of the spring portion, and in this embodiment, five press contact portions are provided. However, the number of press contact portions is not limited to this. is not. Also, the number of apertures formed in the spring portion is not limited to the number of these embodiments, but can be arbitrarily changed to obtain a contact spring having the same effect.

In the contact spring shown in FIG. 3, a notch groove 39 is formed at the center of the spring portion 32 almost from the tip to the fixing portion 31 similarly to the conventional contact spring, and is divided into two by the notch groove 39. Notch grooves 40a, 40b shorter than the central notch groove 39 are formed at the end portions of the respective spring portions 32a, 32b. The reinforcing plate 41 having a constant width d is welded to the portion.

When the contact spring is configured in this manner, the notch grooves 39, 40a, and 40b have openings substantially formed with no non-opening portions between the notch grooves 33, 40a and 40b. A contact spring having the same effect as a contact spring having an opening formed in a spring portion as in the example can be obtained.

[0025]

According to the present invention, a contact spring for electrically connecting the shadow mask and the inner conductive film formed on the inner surface of the funnel is fixed to the mask frame, a spring extending from the fixed portion, and A structure comprising a plurality of pressure contact portions provided at the distal end portion of the spring portion and pressed against the inner conductive film, and having a plurality of apertures at positions close to the pressure contact portion of the spring portion, a plurality of holes for the inner conductive film. The variation in the contact pressure of the pressure contact portion is reduced, and the contact with the inner surface conductive film is made uniform, so that stable contact can be obtained. This eliminates the temporary contact failure that has conventionally occurred when external shocks or vibrations are applied, and reduces the withstand voltage deterioration and the detachment of the inner conductive film piece, resulting in high reliability and good quality. Color picture tube.

[Brief description of the drawings]

FIG. 1A is a view showing a configuration of a main part of a color picture tube according to an embodiment of the present invention, and FIG. 1B is a view showing a structure of a contact spring.

FIG. 2 is a view showing a structure of a contact spring according to another embodiment of the present invention.

FIG. 3 is a view showing a structure of a different contact spring according to another embodiment of the present invention.

FIG. 4 is a diagram showing a configuration of a color picture tube.

FIG. 5 is a view showing a structure of a contact spring of a conventional color picture tube.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Panel 2 ... Funnel 3 ... Metal back layer 4 ... Phosphor screen 5 ... Shadow mask 7 ... Mask frame 10 ... Large diameter part 15 ... Inner conductive film 30 ... Contact spring 31 ... Fixed part 32 ... Spring part 33 ... Press contact part 35 non-opening part 36 ... opening 37 ... opening 39 ... notch groove 40a, 40b ... notch groove 41 ... reinforcing plate

Continuation of the front page (72) Inventor Munechiya Tani 1-9-2, Hara-cho, Fukaya-shi, Saitama Pref. Showa 57-78564 (JP, U) Actually open Showa 52-99765 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01J 29/02

Claims (1)

(57) [Claims] 1. A shadow mask mounted on a peripheral portion of a mask body and mounted inside a panel of an envelope including a panel and a funnel; an inner conductive film formed on an inner surface of the funnel; A contact spring for electrically connecting the shadow mask and the inner conductive film, wherein the contact spring is fixed to the mask frame; a spring extending from the fixation; A color picture tube comprising a plurality of press-contact portions provided at the tip of the portion and press-contacting the inner surface conductive film, wherein the contact spring has a plurality of openings at positions near the press-contact portion of the spring portion. A color picture tube characterized by being formed in a color picture tube.