JP3089782B2 - Method for manufacturing electron gun cathode assembly - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an electron gun cathode structure in which a spacer for defining a distance between first and second grids and a first grid are fixed to the same plane of an insulator. It is about.

[0002]

2. Description of the Related Art In an electron gun cathode assembly, first and second electron guns are provided.
The distance d ₁₂ between grid is one of the parameters that determine the cut-off voltage, this d ₁₂ varies, the cut-off voltage varies. Therefore, in order to keep d ₁₂ constant, a structure in which a d ₁₂ spacer 11 made of an insulating material is interposed between the first and second grids 12 and 13 has been adopted as shown in FIG. I was

In order to manufacture the electron gun cathode assembly shown in FIG. 3, both surfaces of the d ₁₂ spacer 11 are metallized, and the first grid 12 and the d ₁₂ spacer 1 are mounted on the shaft 14 a of the brazing jig 14.
Inserting the first and the second grid 13, had the opposed surface and the d ₁₂ spacer 11 between the first grid 12 and the d ₁₂ spacer 11 brazed to the surface facing the second grid 13.

However, in the electron gun cathode structure shown in FIG. 3, there is a variation in d _{12 due} to the d ₁₂ spacer 11, the thickness of the brazing material and the metallization, and the flatness of the first and second grids 12 and 13. Occurs.

Therefore, as shown in FIG. 4, a metal d ₁₂ spacer 15 and a first grid 16 are fixed to the same plane 17 a of an insulator 17, and a second grid (not shown) is fixed to d _12.
An electron gun cathode structure was considered that was fixed to the surface of the spacer 15 opposite to the insulator 17. In such an electron gun cathode structure, the step surface between the opposite side is the d ₁₂ and the insulator 17 with d ₁₂ spacer 15 and the first grid 16.

In order to manufacture the cathode structure of the electron gun shown in FIG. 4, the plane 17a of the insulator 17 is metallized, the insulator 17 is inserted through the shaft 18a of the brazing jig 18, and the first grid 16 and d ₁₂ The spacer 15 is placed on the plane 17a. Then, while pressing the these first grid 16 and d ₁₂ spacer 15 by the pressing portion 18b, the first grid 16
The surface facing the opposing surface and d ₁₂ spacer 15 with the insulator 17 and the insulator 17 has been brazed.

[0007]

In the electron gun cathode structure of FIG. 4 [0008], rather than the structure of Figure 3, once it can accurately define the d _12. However, in the manufacturing method shown in FIG. 4, the insulator 17, the first grid 16 and d ₁₂ spacer 1
5 flatness, brazing material, metallization and d ₁₂ spacer 1
No measures have been taken against variations in the thickness of the first grid 16, the thickness of the first grid 16, and the like. Thus, d ₁₂ is not prescribed in the always accurate, it was not always able to reduce the variation in the cut-off voltage.

[0008]

SUMMARY OF THE INVENTION A method of manufacturing an electron gun cathode assembly according to the present invention comprises first and second grids 16,2.
In a method for manufacturing an electron gun cathode assembly, a spacer 15 for defining a distance d ₁₂ between the first and fourth grids 4 and the first grid 16 are fixed to the same plane 17 a of an insulator 17.
First and second surface 21b, the step of 21c is the distance d ₁₂
Providing a member 21 equal to the first surface 21;
mounting the first grid 16 on the second surface 21b, and mounting the spacer 15 on the second surface 21c;
Placing the insulator 17 on the first grid 16 and the spacer 15 from the flat surface 17a side; Is fixed to the flat surface 17a.

[0009]

In the method for manufacturing the cathode structure of the electron gun according to the present invention, either the fixed portion between the insulator 17 and the first grid 16 or the fixed portion between the insulator 17 and the spacer 15 plays a role of buffering. Even if the flatness of the insulator 17, the first grid 16 and the spacer 15, the thickness of the fixing material, the metallization and the spacer 15, the thickness of the first grid 16, and the like vary, the first and the second steps are caused by the step of the member 21. the distance d ₁₂ between the second grid 16 and 24 is accurately defined.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention applied to manufacture of an electron gun cathode structure having the same structure as that of FIG. 4 will be described below with reference to FIGS. Note that the same components as those in FIG.
The same reference numerals are given.

In this embodiment, the brazing jig 1 shown in FIG.
A brazing jig 21 different from 8 is used. In the brazing jig 21, a step between a central surface 21b provided with the shaft 21a and two surfaces 21c on both sides of the surface 21b and lower than the surface 21b is formed between the first and second grids. equal to the distance d ₁₂ to be set.

Then, the flat surface 17a of the insulator 17 is metallized, and the first grid 16 is connected to the shaft 21a of the brazing jig 21.
Placed on the surface 21b in the insertion state into places the metal d ₁₂ spacers 15 on the surface 21c. Then, a plane 17 is placed on the first grid 16 and the d ₁₂ spacer 15.
The insulator 17 is placed from the side a. Next, the first grid 16 and the insulator 1 are pressed while pressing the insulator 17 with the pressing portion 21d.
The surface facing the opposing surface and d ₁₂ spacer 15 with the insulator 17 with 7 to brazing.

[0013] In the above such embodiment, when pressing at the time of brazing, either the d ₁₂ spacer 15 and the first grid 16 or brazing portion between the insulator 17 or brazing portion between the insulator 17 Acts as a buffer. Therefore, the insulator 17, the flatness and the first grid 16 and d ₁₂ spacer 15, the brazing material, the thickness and the metallization and d ₁₂ spacer 15, even if there are variations in the thickness or the like of the first grid 16, a row d ₁₂ is accurately defined by the step of Tsukechigu 21.

Accordingly, the insulator 17 which has been sintered but has not been polished on the flat surface 17a can be used as the insulator 17. In addition, the degree of control over the thickness of the brazing material, the thickness of the metallization, and the like can be reduced.

In this embodiment as described above, the brazing jig 2 in which the step between the surface 21b and the surface 21c is 0.256 mm is used.
With 1, to produce 14 samples, was measured d ₁₂ samples using Haisometto (trade name) is a confocal microscope, was obtained following such results. Note that No indicates a sample number, and the unit is mm.

No1 0.256 No2 0.256 No3 0.255 No4 0.254 No5 0.253 No6 0.260 No7 0.260 No8 0.252 No9 0.251 No10 0.250 No11 0.264 No12 0. 263 No13 0.247 No14 0.266 Average 0.256 Standard deviation 0.006

[0017] As is clear from the results, in the present embodiment can be very small variations in the d _12. Further, as described above, the manufacture of the insulator 17 is easy, and the management of the thickness of the brazing material, the thickness of the metallization, and the like are also easy. Therefore, it is possible to easily manufacture an electron gun cathode assembly having a small variation in cutoff voltage.

[0018] Incidentally, d ₁₂ spacer 1 in the step shown in FIG. 1
After the 5 and the first grid 16 are fixed to the insulator 17, the sleeve holder 22 is brazed to the insulator 17 on the side opposite to the first grid 16 as shown in FIG.

Thereafter, the inner sleeve 23 is sprayed with an oxide to form a cathode, and the inner sleeve 23 is inserted into the sleeve holder 22. Then, while collating the distance d ₀₁ between the cathode and the first grid 16, the inner sleeve 23 is attached to the sleeve holder 22 by laser welding or resistance welding.
The inner sleeve is fixed to the inside.

[0020] Next, the G _Half of fixing together the d ₁₂ spacer 15 or the like and the second grid 24 by laser welding or resistance welding, to beading the structure and the third and subsequent grid in this state. Then, heating is performed by laser welding or resistance welding, and connection is further performed to complete the electron gun cathode assembly.

[0021]

According to the method for manufacturing an electron gun cathode structure according to the present invention, variations occur in the flatness of the insulator, the first grid and the spacer, the thickness of the fixing material, the metallization and the spacer, and the thickness of the first grid. Even so, the distance between the first and second grids is accurately defined by the step of the member, so that an electron gun cathode assembly with less variation in cutoff voltage can be easily manufactured.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is a process system diagram showing the whole manufacturing process of an electron gun cathode assembly including one embodiment.

FIG. 3 is a side view showing a method of manufacturing an electron gun cathode structure different from the electron gun cathode structure to which the present invention is applied.

FIG. 4 is a side view showing a conventional example of the present invention.

[Explanation of symbols]

15 d ₁₂ Spacer 16 First grid 17 Insulator 17a Flat surface 21 Brazing jig 21b surface 21c surface 24 Second grid

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-57-98951 (JP, A) JP-A-3-182203 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01J 9/18

Claims (1)

(57) [Claims] 1. A method of manufacturing an electron gun cathode assembly, wherein a spacer for defining a distance between first and second grids and the first grid are fixed to the same plane of an insulator. A step of preparing a member having a step on the second surface equal to the distance; a step of placing the first grid on the first surface; and a step of placing the spacer on the second surface. Mounting the insulator on the first grid and the spacer from the plane side; and fixing the first grid and the spacer to the plane while pressing the insulator toward the member. And manufacturing the electron gun cathode assembly.