JPH05314928A - Cathode ray tube device method to use it and method to ground it - Google Patents

Abstract

PURPOSE:To improve the reliability of withstand voltage while maintaining the shielding performance of a deflection yoke on an alternating electric field. CONSTITUTION:A conductive film 8 to form an electric field shield thereon and a conductive film 6 formed on a funnel mainframe separated with each other are ranged from the neck portion to the cone portion of a glass bulb 20. A deflection yoke is arranged on the conductive film 8 via an insulating sheet and the conductive film 8 is impedance-grounded via an impedance element 10 to form a shielding face in front of the deflection yoke and improve the reliability of withstand voltage on the deflection yoke.

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 device, a method of using the same, and a method of grounding the same, and more particularly to a device for reducing an alternating electric field radiated from a deflection yoke thereof, and in particular, an improvement in withstand voltage and the like with the deflection yoke. It is about.

[0002]

2. Description of the Related Art FIG. 8 is a block diagram of a conventional cathode ray tube.
In FIG. 8, the funnel part 1 is composed of a neck part 1a, a cone part 1b connecting the neck part 1a and a funnel body part 1c described later, and a funnel body part 1c having a high-pressure anode button 1d, and a fluorescent film on the inner surface. The funnel body 1c is frit-sealed on the panel portion 2 arranged at one end on the side opposite to the side connected to the cone portion 1b.
Reference numeral 1e denotes a joint between the neck portion 1a and the cone portion 1b, which is a portion called a neck seal line, which has a slightly thin glass wall and is weaker in strength than other portions. The glass bulb 20 is configured as described above.

An electron gun 3 is sealed in the neck portion 1a. Explosion-proof bands 4 for assuring explosion-proof characteristics are wound around the side surfaces of the panel portion 2, and hooking portions 4a for suspending the glass bulb 20 in a casing (not shown) are provided at four corners.
Are provided integrally. Further, a silicon resin film 5 for insulation is formed around the high-voltage anode button 1d provided on the funnel body 1c. Further, a conductive film 6 for adding capacitance to the cathode ray tube is formed on the outer surface of the funnel body 1c. This conductive film 6
Are usually formed by applying graphite.
Reference numeral 28 is a straight line parallel to the neck portion 1a and indicates the tube axis of the cathode ray tube.

As shown in FIG. 9, a deflection yoke 7 for deflecting an electron beam is attached to the cathode ray tube constructed as described above at a position between the cone portion 1b and the neck portion 1a. .. The deflection yoke 7 is composed of a horizontal deflection coil, a vertical deflection coil, and members of the deflection yoke body.

Next, the operation will be described. Neck 1a
When an electron beam is emitted from the electron gun 3 sealed in
The emitted electron beam is deflected by a predetermined amount in the horizontal and vertical directions by the horizontal deflection coil and the vertical deflection coil of the deflection yoke 7 and is scanned on the fluorescent film formed on the inner surface of the panel portion 2 to display a desired image. Put out. The deflection width at this time is inversely proportional to the square root of the voltage applied to the anode button 1d.

In the above-described structure, when the deflection yoke 7 deflects the electron beam, no measure is taken to shield the alternating electric field generated radially around the deflection yoke 7, which is harmful to the human body. There is a problem that the alternating electric field is transmitted through the funnel portion 1 and the panel portion 2 of the cathode ray tube and radiated in front of the cathode ray tube.

In the conventional cathode ray tube device with the above problems improved, the funnel portion is radiated to the front surface of the face panel in a predetermined region from the cone portion where the deflection yoke of the funnel portion is fitted to the neck portion. The alternating electric field reducing means for reducing the alternating electric field of the deflection yoke is provided.

That is, the grounded conductive film of the alternating electric field reducing means is connected from the region of the cone portion having a diameter larger than the opening diameter of the horizontal deflection coil constituting the deflection yoke to the joint between the neck portion and the cone portion. It is formed on the outer surface of the cone part up to the area that does not reach.

That is, in the conventional example, the alternating electric field of the deflection yoke transmitted through the funnel portion and radiated to the front surface of the face panel is reduced in a predetermined region from the cone portion where the deflection yoke of the funnel portion is fitted to the neck portion. An alternating electric field reducing means is provided, and 0 is provided on the inner peripheral surface of the opening of the deflection yoke.
Since the equipotential surface of V, that is, the electric field shield surface is formed, it is possible to reduce the alternating electric field transmitted through the funnel and the face panel and radiated to the front surface of the face panel.

A conventional example will be specifically described below with reference to the drawings. FIG. 10 shows a configuration diagram of a cathode ray tube device according to an example in which an alternating electric field reducing means is provided. The same reference numerals as those in FIGS. 8 and 9 denote the same or corresponding portions, and 8 is a conductive film for forming an electric field shield surface. 6 is a conductive film for electric field shielding that is provided by applying graphite from the cone portion 1b to the neck portion 1a so as to make electrical contact with 6, and is formed to cover the front surface of the opening of the deflection yoke.

Reference numeral 9 is an insulating sheet provided to electrically insulate the conductive film 8 and the coil portion of the deflection yoke. This has a funnel shape as shown in FIG. 11, and is attached to the cone portion 1b and the neck portion 1a of the funnel. Then, as shown in FIG. 12, the deflection yoke 7 is attached from above the insulating sheet 9 of the glass bulb 20 configured as described above.

Next, the operation in the conventional usage will be described. In the thus configured cathode ray tube device, the conductive film 8 becomes an equipotential surface of 0 V by grounding the conductive film 8, and the conductive film 6 is electrically connected to the conductive film 8. A surface having an electric field shield effect is formed in the front area, and the deflection yoke 7 and the funnel portion 1 are formed.
The alternating electric field radiated to the front surface of the face panel after passing through is reduced. Further, since the insulating sheet 9 is interposed between the coil portion of the deflection yoke 7 and the conductive film 8, the coil portion of the deflection yoke 7 and the conductive film 8 are normally electrically insulated. Therefore, problems such as discharge do not occur.

As described above, according to the conventional example, from the neck portion 1a of the funnel portion 1 of the glass bulb 20 to the cone portion 1b.
To form a conductive film 8 for electric field shield electrically connected to the conductive film 6, a deflection yoke 7 is arranged via an insulating sheet 9 on the conductive film 8, and the conductive film 8 is grounded. Since an equipotential surface of 0 V is formed on the front surface of, the alternating electric field transmitted through the funnel portion 1 of the deflection yoke 7 can be reduced by about 40% as compared with the conventional case by this equipotential surface.

[0014]

The conventional cathode ray tube device is constructed and used as described above, and the deflection yoke 7 is used.
It is possible to reduce the alternating electric field generated in front of the cathode ray tube. By the way, with respect to the current flowing through the coil of the deflection yoke 7, the insulating film covered by the coil wire of the deflection yoke 7 and the insulating sheet 9 provided between the deflection yoke 7 and the conductive film 8 are doubled. The insulating layer needs to guarantee a withstand voltage of an AC voltage of approximately 5 KV. However, regarding this reliability, the fact that the conductive film 8 of the cone portion 1b provided to reduce the alternating electric field is grounded and the variation in the material and shape of the insulating layer of the coil wire of the deflection yoke 7 are taken into consideration. There was a problem that the insulation reliability could not be satisfied for an AC of about 5 KV.

The present invention has been made to solve the above problems, and it is possible to improve the reliability of the withstand voltage between the deflection yoke and the conductive film while maintaining the function of attenuating the alternating electric field of the deflection yoke. An object of the present invention is to obtain a cathode ray tube device and a method of using the cathode ray tube device.

It is another object of the present invention to provide a method of grounding a cathode ray tube device which can assure a withstand voltage and further improve the shield performance.

[0017]

In the cathode ray tube device of the present invention, the conductive film on the funnel body and the conductive film on the cone side are integrated, and the conductive film is grounded by impedance.

Further, both conductive films are separately provided, and at least one of them is impedance grounded.

Further, the impedance element used for impedance grounding is variably provided.

According to the method of using the cathode ray tube device of the present invention, the conductive films of the cone side and the funnel body are independently provided, and at least one of the conductive films is impedance-grounded for use.

Further, the impedance of the impedance element is made variable and the impedance is variably adjusted for use.

Further, a specific or variable impedance element is used between the cone portion side and the conductive film of the funnel body portion.

In the method of grounding the cathode ray tube device of the present invention, both conductive films of the cone portion side and the funnel body portion are independently provided and both conductive films are grounded.

[0024]

In the cathode ray tube device according to the present invention, the cone side and the conductive film of the funnel body are integrated and grounded to improve the impedance and the insulation resistance.

Further, in the cathode ray tube device and the method of using the same according to the present invention, the conductive film on the cone portion side relating to the insulation resistance is separated from the conductive film on the funnel body portion to improve the insulation resistance. The conductive film is grounded by impedance.

Further, an external impedance element used for impedance grounding can be variably provided to adjust the impedance to an appropriate value.

In the method of using the cathode ray tube device according to the present invention, an impedance element is connected between the cone portion side and the conductive film of the funnel body portion to increase the impedance,
Improves insulation resistance.

In the method of grounding the cathode ray tube device according to the present invention, the conductive film on the cone side and the conductive film on the funnel body are separated, and their resistance values and impedances are made independent of each other, and both conductive films are grounded for shielding performance. Improve.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1 to 7 show respective embodiments of the present invention. (A) of each drawing is a view for explaining a main part of a cathode ray tube device, and (b) of each drawing is from a conductive film to a ground. The equivalent circuit up to is shown. 1 to 7, 6 is a conductive film of the funnel body, 8 is a conductive film on the cone side from the neck to the cone, which is the same as that described in the conventional example, In FIGS. 1 and 3 to 7, both conductive films 6 and 8 are glass bulbs 20.
This is different from the conventional example in that they are provided independently of each other by a predetermined distance in the tube axis direction. It is to be noted that both conductive films 6 and 8 in FIG. 2 are made to overlap each other in the middle or are continuously formed by coating so as to be electrically conductive to each other, which is the same as the conventional example.

1 (a) to 7 (a), elements other than the conductive films 6 and 8 and the ground portion have the same structure as the cathode ray tube device described in the conventional example, and are not shown. ..
Further, in FIGS. 1B to 7B, RF, L
F indicates the resistance value and inductance of the conductive film 6 of the funnel body, and RC and LC indicate the resistance value and inductance of the conductive film 8 on the cone side, respectively.
Indicates the impedance of the impedance element 10 or 10A.

Example 1. In FIG. 1, the conductive film 6 on the funnel portion is grounded, and the conductive film 8 on the cone portion side is grounded via an impedance element 10 having an impedance L (same in the following embodiments). That is, the conductive film 8 is impedance grounded by the impedance element 10. In this embodiment, the conductive film 8 that is a conductive film portion that is directly related to the breakdown voltage with respect to the deflection yoke is separated from the conductive film 6 that is a conductive film portion that is not relatively related to the breakdown voltage to withstand voltage with respect to the deflection yoke. The impedance is grounded to improve the reliability. Further, the conductive film 6 is directly grounded so as not to deteriorate the shield performance.

By the way, in order for the conductive film to act as an electric field shield, it is preferable that its resistance value and inductance be small. For example, in the case of the conductive film 8, both RC and LC should be small. Further, from the viewpoint of improving the reliability of the withstand voltage, impedance grounding is preferable, and in this embodiment, the contradictory performances of both can be satisfied.

Example 2. In FIG. 2, the conductive film 8 on the cone side and the conductive film 6 on the funnel main body, which are made to be electrically conductive to each other, are impedance grounded by the impedance element 10 in order to improve the reliability of the withstand voltage of the deflection yoke.

Example 3. In FIG. 3, the conductive film 6 is directly grounded, and the conductive film 8 is grounded via the variable impedance element 10A. Variable impedance element 10A
By adjusting the impedance, the impedance can be adjusted to improve the reliability of the withstand voltage without variation without lowering the shield performance.

Example 4. In FIG. 4, both conductive films 6 and 8
Are separated and grounded separately. The resistance values and reactances RF, LF, RC, and LC of the conductive films 6 and 8 are reduced by the amount of separation, which can further improve the shield performance.

Example 5. In FIG. 5, both conductive films 6 and 8
Are grounded via a common impedance element 10. Since the impedance is grounded, the reliability of the withstand voltage with respect to the deflection yoke is further improved as compared with the case of the first embodiment.

Example 6. In FIG. 6, both conductive films 6, 8
The impedance elements 10 are used to connect the two.

Example 7. In FIG. 7, both conductive films 6 and 8
Is connected by using the impedance element 10, and one end of the conductive film 6 side is grounded to improve the reliability of the withstand voltage with respect to the deflection yoke.

Example 8. Even if the variable impedance element 10A shown in FIG. 3 is used in place of the impedance element 10 in the first, second, fifth, and seventh embodiments, the same effect as that of the third embodiment can be obtained.

Example 9. Further, in FIG. 3, even if the fixed impedance element 10 is used instead of the variable impedance element 10A, the reliability of the withstand voltage can be improved.

In the above embodiment, in order to separate the conductive films 6 and 8, a tape having a constant width is attached in advance to the outer periphery of the tube wall, and in this state, the material of the conductive film, for example, graphite powder in the binder is used. It may be formed by spray painting and then the tape may be peeled off. A jig may be used instead of this tape.

In the above description, the impedance element means an AC resistance component and / or a DC resistance component.

Regarding the shielding performance, the frequency characteristic of the test standard, especially the characteristic of several tens of KHz or less is important. In the past, the direct current component was emphasized and only the direct current resistance component of the conductive film as the alternating electric field reducing means was focused. However, in the present invention, it is possible to improve the reliability of the withstand voltage characteristics of the deflection yoke and the conductive film while considering the AC component.

[0044]

As described above, according to the present invention, the conductive film on the cone side and the conductive film on the funnel body are used integrally or separately, and the conductive film is impedance grounded. Since it is configured or used, there is an effect that the reliability of the withstand voltage can be improved without lowering the shield performance against the radiation mainly due to the electric field from the deflection yoke.

Further, the same effect as described above can be obtained by separating the conductive film of the cone portion side and the conductive film of the funnel body portion and connecting them by the impedance element.

Further, by making the impedance element variable, it is possible to correct variations in the reliability of the withstand voltage.

Further, by separating the conductive film of the cone portion side from the conductive film of the funnel body portion and grounding them, there is an effect that the shield performance can be improved without lowering the reliability of the withstand voltage.

[Brief description of drawings]

FIG. 1 is an explanatory diagram according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram according to a second embodiment of the present invention.

FIG. 3 is an explanatory diagram according to a third embodiment of the present invention.

FIG. 4 is an explanatory diagram according to a fourth embodiment of the present invention.

FIG. 5 is an explanatory diagram according to a fifth embodiment of the present invention.

FIG. 6 is an explanatory diagram according to Embodiment 6 of the present invention.

FIG. 7 is an explanatory diagram according to Embodiment 7 of the present invention.

FIG. 8 is a configuration diagram of a conventional cathode ray tube.

FIG. 9 is a configuration diagram of a conventional cathode ray tube device.

FIG. 10 is a configuration diagram of another conventional cathode ray tube device.

FIG. 11 is a perspective view of an insulating sheet.

FIG. 12 is a configuration diagram of another conventional cathode ray tube device.

[Explanation of symbols]

 1 Funnel part 1a Neck part 1b Cone part 1c Funnel body part 1d Anode button 2 Panel part 3 Electron gun 4 Explosion-proof band 5 Silicon resin film 6 (Funnel body part) Conductive film 7 Deflection yoke 8 (Cone side) Conductive film 9 Insulation sheet 10 Impedance element 10A Variable impedance element 20 Glass bulb

Claims (7)

[Claims] 1. A neck portion in which an electron gun is enclosed, a funnel body portion in which a conductive film for adding capacitance is provided on a part of the outer surface, and a cone connecting the neck portion and the funnel body portion. Funnel part composed of parts,
Having a fluorescent film on the inner surface, a face panel arranged at one end on the side opposite to the side connected to the cone portion of the funnel body, and fitted from the cone portion of the funnel portion to the neck portion, A cathode ray tube device having a deflection yoke for deflecting an electron beam emitted from an electron gun, and a conductive film provided in a predetermined region from the cone portion to which the deflection yoke of the funnel portion is fitted to the neck portion. In the above, a cathode wire characterized in that both the conductive films on the funnel main body part and the cone part side are overlapped in the middle or continuously provided so that the conductive films are electrically conductive, and the conductive film is impedance grounded. Tube device. 2. A neck portion in which an electron gun is sealed, a funnel body portion provided with a conductive film for adding capacitance on a part of its outer surface, and the neck portion and the funnel body portion are connected to each other. A funnel part composed of a cone part,
Having a fluorescent film on the inner surface, a face panel arranged at one end on the side opposite to the side connected to the cone portion of the funnel body, and fitted from the cone portion to the neck portion of the funnel portion, A cathode ray tube device having a deflection yoke for deflecting an electron beam emitted from an electron gun, and a conductive film provided in a predetermined region from the cone portion to which the deflection yoke of the funnel portion is fitted to the neck portion. 2. A cathode ray tube device according to claim 1, wherein both the conductive film on the cone portion side and the conductive film on the funnel body portion are independently provided, and the conductive film on the cone portion side and / or the conductive film on the funnel body portion are impedance-grounded. 3. The cathode ray tube device according to claim 1, wherein the external impedance element used for impedance grounding is a variable type whose impedance can be varied. 4. A neck portion in which an electron gun is sealed, a funnel body portion in which a conductive film for adding capacitance is provided on a part of the outer surface, and the neck portion and the funnel body portion. A funnel portion formed of connecting cone portions, a face panel having a fluorescent film on the inner surface, and a face panel disposed at one end of the funnel body portion opposite to the side connected to the cone portion, and the cone of the funnel portion. From the cone portion to the neck portion, which has a deflection yoke that is fitted from the portion to the neck portion and that deflects the electron beam emitted from the electron gun. In a cathode ray tube device in which a conductive film is provided in a predetermined region, the conductive film of the cone side and the conductive film of the funnel body are independently provided, and at least one of the conductive films is installed. A method of using a cathode ray tube device, which is characterized in that it is used with a pinned ground. 5. A method of using a cathode ray tube device, comprising variably providing an external impedance element used for impedance grounding and variably adjusting the impedance of the external impedance element. 6. A neck portion in which an electron gun is sealed, a funnel body portion in which a conductive film for adding capacitance is provided on a part of the outer surface thereof, and the neck portion and the funnel body portion. A funnel portion composed of a connecting cone portion, a face panel having a fluorescent surface on the inner surface, and a face panel arranged at one end of the funnel body portion opposite to the side connected to the cone portion, and the cone of the funnel portion. Section from the cone portion to the neck portion, and a deflection yoke for deflecting an electron beam emitted from the electron gun. In a cathode ray tube device in which a conductive film is provided in a predetermined area, conductive films of the cone side and the funnel body are independently provided, and a specific or change is made between the conductive films. A method of using a cathode ray tube device, characterized in that the cathode ray tube device is used via an impedance element. 7. A neck portion in which an electron gun is sealed, a funnel body portion in which a conductive film for adding capacitance is provided on a part of the outer surface, and the neck portion and the funnel body portion. A funnel portion composed of a connecting cone portion, a face panel having a fluorescent surface on the inner surface, and a face panel arranged at one end of the funnel body portion opposite to the side connected to the cone portion, and the cone of the funnel portion. From the cone portion to the neck portion, which has a deflection yoke that is fitted from the portion to the neck portion and that deflects the electron beam emitted from the electron gun. In a cathode ray tube device in which a conductive film is provided in a predetermined region, conductive films of the cone side and the funnel body are independently provided, and both conductive films are grounded. Grounding method for cathode ray tube devices.