JPH0982239A - Cathode ray tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduces the movement of the tip of a bulb spacer fixed to an electron beam emitting end part electrode caused by the shock or vibration applied to a cathode ray tube. SOLUTION: A cathode ray tube is formed in such a way that a bulb spacer 21 made of an elastic material for pressing the tip against a conductive film 16 formed on the inner surface of a funnel 11 is fixed to an electron beam emitting end part electrode of an electron gun. The bulb spacer is fixed to the electron beam emitting end part electrode through a supporting member 23 capable of performing elastic displacement in the direction vertical to the tube axis.

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, and more particularly to a cathode ray tube having an improved mounting structure of a valve spacer for supporting an electron beam emitting end side of an electron gun.

[0002]

2. Description of the Related Art Generally, a cathode ray tube has an envelope composed of a panel and a funnel, and an electron beam emitted from an electron gun arranged in the neck of the funnel is attached to the outside of the funnel. The fluorescent screen formed on the inner surface of the panel is deflected by the magnetic field generated by the horizontal direction and is vertically scanned to form an image display structure.

The above electron gun is formed in a structure in which a cathode and a plurality of electrodes sequentially arranged in the phosphor screen direction from the cathode are integrally fixed by an insulating support. In the electron gun shown in FIG. A shield cup is attached to the electron beam emitting end on the phosphor screen side,
Electron beam emitting end electrode 1 consisting of this shield cup
A valve spacer 4 made of a plurality of elastic members, the tip of which is in pressure contact with the conductive film 3 formed by coating on the inner surface of the funnel 2.
Is installed. The valve spacer 4 holds the electron beam emitting end of the electron gun coaxially with the tube axis (Z axis),
In addition, the high voltage supplied from the anode terminal provided on the funnel through the conductive film 3 formed on the inner surface of the funnel is guided to the final accelerating electrode 5 located on the electron beam emission end side of the electron gun. is there.

As such a valve spacer, displacement caused by momentary shock or vibration applied during transportation of the cathode ray tube or installation in a set is minimized, and the spacer supplied through the conductive film 3 is minimized. A strong spring pressure that stably guides the voltage to the final accelerating electrode is required. On the other hand, the cathode ray tube is assembled by inserting an electron gun to which a valve spacer is attached in advance through the neck end opening of the funnel, which has a conductive film applied and formed on its inner surface. Therefore, if the spring pressure of the valve spacer is strong, the conductive film is scraped off by the contact of the valve spacer when the electron gun is inserted, and the scraped conductive film adheres to the electrodes of the electron gun and deteriorates the withstand voltage characteristics. Cause.

Therefore, conventionally, the spring pressure of the valve spacer cannot be made too strong, and a relatively soft stainless steel material such as Inconel is used to displace the cathode ray tube against shock or vibration, to cause conductive contact with the conductive film, and It is a compromise design that considers the balance of contact pressure against the conductive film when the electron gun is inserted.

[0006]

As described above, the valve spacer attached to the electron beam emitting end electrode of the electron gun of the cathode ray tube minimizes displacement due to shock and vibration applied to the cathode ray tube, and A strong spring pressure that stably guides the high voltage supplied through the conductive film on the inner surface of the funnel to the final acceleration electrode is required. On the other hand, with respect to the insertion of the electron gun at the time of assembling the cathode ray tube, if the spring pressure is strong, the conductive film is scraped off due to the contact of the valve spacer, and the scraped conductive film adheres to the electrode of the electron gun, etc. It causes deterioration of withstand voltage characteristics. Therefore, in the past, the spring pressure of the valve spacer could not be made too strong, and the relatively soft stainless steel material such as Inconel was used to displace the cathode ray tube against impact or vibration, conductive contact with the conductive film, and electron gun insertion. It is a compromise design that considers the balance of contact pressure against the conductive film.

However, in the valve spacer manufactured by such a compromise design, when an impact or vibration is applied to the cathode ray tube, the electron beam emission end side of the electron gun is displaced in the direction perpendicular to the tube axis, Due to the displacement, the tip of the valve spacer moves over the conductive film on the inner surface of the funnel to scrape off the conductive film, and the scraped conductive film adheres to the electrodes of the electron gun, etc., causing deterioration in withstand voltage characteristics. There is a problem.

That is, as shown in FIG. 5A, the electron beam emitting end electrode 1 is provided with a valve spacer 4 having a length a.
Is attached to the side wall parallel to the tube axis, that is, at an angle θ to the tube axis, the electron beam emission end side of the electron gun is displaced in the direction orthogonal to the tube axis due to the impact or vibration applied to the cathode ray tube. Then, the angle θ changes, and along with this change in the angle θ, the length b (=
a · cos θ) changes and the tip moves on the conductive film 3. At this time, the conductive film 3 is scraped off by the tip portion thereof, which causes deterioration of withstand voltage characteristics.

The present invention has been made to solve the above problems, and even if the electron beam emitting end side of the electron gun is displaced in a direction perpendicular to the tube axis due to impact or vibration applied to the cathode ray tube, It is an object of the present invention to configure a cathode ray tube which does not deteriorate the withstand voltage characteristics by reducing the movement of the tip of the bulb spacer attached to the electron beam emitting end electrode.

[0010]

An electron gun having a plurality of electrodes is arranged in a neck of a funnel forming an envelope, and an electron beam emitting end electrode of the electron gun has a tip end portion of the inner surface of the funnel. In a cathode ray tube having a valve spacer made of an elastic material, which is in pressure contact with a conductive film provided on the substrate, the valve spacer is attached to the electron beam emitting end electrode and can be elastically displaced in a direction perpendicular to the tube axis. Mounted through.

Further, the supporting member is formed in a shape having double folded portions on both sides of the valve spacer attaching portion to which the valve spacer is attached.

Further, the spring pressure of the valve spacer is made stronger than the spring pressure of the support member.

[0013]

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

FIG. 1 shows a cathode ray tube which is one of the forms.
This cathode ray tube comprises a panel 10 and a funnel-shaped funnel 1.
A phosphor screen 12 is provided on the inner surface of the panel 10 having an envelope made of 1. On the other hand, an anode terminal 14 is provided on the large-diameter portion 13 of the funnel 11, and an inner conductive film 16 is formed by coating from the inner surface of the large-diameter portion 13 of the funnel 11 to the inner surface of the adjacent portion of the neck 15. Further, an electron gun 17 is provided in the neck 15 of the funnel 11.
Are arranged.

The electron gun 17 is composed of a cathode and a plurality of electrodes sequentially arranged in the direction of the phosphor screen 12 from the cathode. The cathode and the plurality of electrodes are integrally fixed by an insulating support. Has been formed. Then, a shield cup 20 is attached to the final accelerating electrode 19 located on the electron beam emitting end side, and the electron beam emitting end electrode composed of this shield cup 20 has its tip pressed against the inner conductive film 16 to cause an electron gun. The electron beam emitting end of 17 is held on the tube axis (Z axis), and the high voltage supplied to the anode terminal 14 is applied to the inner conductive film 16.
Valve spacers 21 made of four elastic materials are attached to guide the final accelerating electrode 19 via.

In particular, in the cathode ray tube of this example, the valve spacer 21 is, as shown in FIG. 2 and FIG. 3, via a support member 23 made of four elastic members attached to the inner wall of the shield cup 20. Installed. Each of the supporting members 23 has a double folded portion 25 parallel to the pipe axis on both sides of the valve spacer mounting portion 24 parallel to the pipe axis to which the valve spacer 21 is attached. Both sides are attached to the inner wall of the shield cup 20 and are elastically displaceable in the direction perpendicular to the tube axis. The valve spacer 21 is attached to the valve spacer attachment portion 24. The spring pressure of the valve spacer 21 attached via the support member 23 is preferably stronger than the spring pressure of the support member 23.

As described above, when the valve spacer 21 is attached to the side wall of the shield cup 20 located at the electron beam emission end through the supporting member 23 which is elastically displaceable in the direction perpendicular to the tube axis, the cathode ray tube is impacted or damaged. The displacement of the electron beam emitting end portion in the direction perpendicular to the tube axis that occurs when vibration or the like is applied can be dispersed into the elastic deformation of the valve spacer 21 and the elastic deformation of the support member 23. Thereby, for the displacement of the electron beam emitting end in the direction perpendicular to the tube axis,
The angle θ formed by the valve spacer 21 with the valve spacer mounting portion 24 parallel to the tube axis of the support member 23, that is, the angle with respect to the tube axis is made smaller than in the conventional structure in which the valve spacer is directly attached to the side wall of the shield cup, The movement of the tip end portion of the valve spacer 21 with respect to the inner conductive film 16 can be reduced, and deterioration of the withstand voltage characteristic caused by the inner surface conductive film being scraped off by the movement of the valve spacer tip portion can be prevented.

For example, the outer diameter of the net 15 is 29.1 mm,
The inner diameter is 23.9 mm, and the outer diameter of the shield cup 20 is 23.
With a 5 mm cathode ray tube, when shock or vibration is applied to it, the maximum displacement of the electron beam emitting end in the direction perpendicular to the tube axis is (23.9 mm-23.5 mm) /2=0.2 mm. Become. The support member and the valve spacer having the same spring pressure in the direction perpendicular to the tube axis on the side wall of the shield cup of the cathode ray tube, that is, the elastic displacement in the direction perpendicular to the tube axis is 0.
If a 1 mm support member is attached and a valve spacer with an elastic displacement of 0.1 mm in the direction perpendicular to the pipe axis is also attached to this support member, the amount of change in angle θ with respect to the above 0.1 mm displacement amount. Δθ is 0.52 °. Therefore, if the length a of the valve spacer is 11 mm, the tip of this valve spacer moves 0.45 mm on the inner conductive film. On the other hand, in the conventional structure in which the valve spacer is directly attached to the side wall of the shield cup, the displacement amount of the valve spacer in the direction perpendicular to the tube axis is 0.2 mm, and the change amount Δθ of the angle θ is 1.04. It becomes °. Therefore, if the length a of the valve spacer is also 11 mm, the tip of the valve spacer moves 1.81 mm above the inner conductive film.

That is, when the valve spacer is attached to the side wall of the shield cup through the support member having the same elastic displacement in the direction perpendicular to the pipe axis, the valve spacer is attached directly to the side wall of the shield cup as compared with the conventional structure. Thus, the movement of the tip portion of the valve spacer on the inner conductive film can be reduced to 1/4. As a result, it is possible to prevent the deterioration of withstand voltage characteristics caused by the inner conductive film being scraped off by the movement of the valve spacer tip.

In the above embodiment, the case where the valve spacer and the support member have the same elastic displacement amount has been described.
When mounting the valve spacer on the shield cup through the support member, the smaller the displacement amount of the valve spacer in the direction perpendicular to the tube axis, the smaller the variation amount Δθ of the angle θ, and the inner conductive film at the tip of the valve spacer. Since the upward movement can be made smaller, by making the spring pressure of the valve spacer stronger than the spring pressure of the support member, the movement of the tip portion of the valve spacer on the inner conductive film can be made smaller, and more preferable results can be obtained. can get.

Next, a different embodiment of the present invention will be described.

In the embodiment shown in FIG. 4A, a support member 23 similar to that of the above-mentioned embodiment is attached to the inner wall of the shield cup 20, and the valve is attached to the valve spacer attachment portion 24 of each support member 23. The spacer 21 is folded back in the middle to form an inverted V shape. Thus, when the valve spacer 21 is folded back in the middle to form an inverted V-shape, the inner surface of the conductive film 16 at the tip of the valve spacer 21 that occurs when shock or vibration is applied to the cathode ray tube as compared with the above-described embodiment. The movement of can be reduced.

In the embodiment shown in FIG. 4 (b), four notches 27 are provided on the side wall of the shield cup 20, and each notch 27 is provided with a support member 23 similar to that of the above embodiment. The valve spacer mounting portion 2 of each supporting member 23
4 has a valve spacer 21 attached thereto. Even with this structure, it is possible to form a cathode ray tube having the same effect as that of the above-described embodiment.

[0024]

EFFECTS OF THE INVENTION A supporting member which is elastically displaceable in a direction perpendicular to the tube axis is attached to an electron beam emitting end electrode of an electron gun, and the tip of the supporting member is pressed against a conductive film provided on the inner surface of the funnel. When a valve spacer made of elastic material is attached, the displacement of the electron beam emitting end of the electron gun in the direction perpendicular to the tube axis caused by impact or vibration on the cathode ray tube causes elastic deformation of the valve spacer and a supporting member. It is possible to disperse in the elastic deformation of the electron beam emitting end electrode compared with the conventional structure in which the valve spacer is directly attached,
It is possible to reduce the movement of the tip portion of the valve spacer with respect to the conductive film, and it is possible to prevent the deterioration of the withstand voltage characteristic caused by the abrasion of the conductive film due to the movement of the tip portion of the valve spacer.

In particular, when the supporting member is formed in a shape having double folded portions on both sides of the valve spacer mounting portion, the valve spacer mounting portion serves as a supporting member for easily elastically displacing in the direction perpendicular to the pipe axis. be able to.

Further, by making the spring pressure of the valve spacer stronger than the spring pressure of the support member, the movement of the tip of the valve spacer on the conductive film can be reduced.

[Brief description of drawings]

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

FIG. 2 is a sectional view showing a mounting structure of the valve spacer.

FIG. 3 is a perspective view showing the mounting structure of the valve spacer.

FIG. 4 (a) and FIG. 4 (b) are views showing different valve spacer mounting structures.

5A and 5B are views showing a conventional valve spacer mounting structure.

[Explanation of symbols]

 11 ... Funnel 14 ... Anode terminal 15 ... Neck 16 ... Conductive film 17 ... Electron gun 19 ... Final accelerating electrode 20 ... Shield cup 21 ... Valve spacer 23 ... Support member 24 ... Valve spacer mounting portion 25 ... Double folded portion 27 ... Notch

Claims (3)

[Claims] 1. An electron gun having a plurality of electrodes is provided in a neck of a funnel forming an envelope, and a tip portion is provided on an inner surface of the funnel at an electron beam emitting end electrode of the electron gun. In a cathode ray tube having a valve spacer made of an elastic material that is pressed against the conductive film, the valve spacer is attached to the electron beam emitting end electrode via a supporting member that is elastically displaceable in a direction perpendicular to the tube axis. A cathode ray tube characterized in that it is installed. 2. The support member is formed in a shape having double folded portions on both sides of a valve spacer attachment portion to which the valve spacer is attached, sandwiching the valve spacer attachment portion.
A cathode ray tube as described. 3. The cathode ray tube according to claim 1, wherein the valve spacer has a spring pressure stronger than that of the support member.