JPH04345729A - Assembly of electron gun for color cathode-ray tube - Google Patents

Abstract

PURPOSE:To provide the assembly of an electron gun for a cathode-ray tube capable of accurately making part positioning. CONSTITUTION:The slight movement of a chuck body in a Y axis direction causes the variation of the illuminance of a laser beam; sent from a laser irradiation device 16, reflected at the tip of a center pin 12, and received with a beam- receiving element 18; according to the position of a center hole 21. The positioning of the center hole 21 of a grid 20 on a straight line connecting the laser irradiation device 16 and the tip of the center pin 12, causes the highest illuminance and stopping the chuck body. Assembly is completed by rotating the grid 20 with the chuck body 19 with the center hole 21 of the grid 20 as a center, looking for a peak value, stopping the rotation at a position where the peak value of the illuminance of a laser beam, from a laser irradiation device 15 and reflected at the tip of a side pin 13, is beam-received with a beam-receiving element 17, moving the chuck body 19 having an offset distance in a X axis direction to be lowered, and inserting each of the hole 21 and holes 22 and 23 to each of the pins 12 and 13 and a pin 14.

Description

[Detailed description of the invention]

[Object of the invention]

0002

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for assembling an electron gun for a color cathode ray tube, which positions a grid of an electron gun for a color cathode ray tube.

0003

2. Description of the Related Art Generally, when assembling an electron gun for a cathode ray tube (CRT) such as a color cathode ray tube, plate-shaped or cap-shaped grids constituting the electron gun are stacked alternately with spacers in a predetermined combination. I am assembling it.

Conventionally, as shown in FIG. 8, for example, three pins 1, 2, 3 set upright on an assembly jig are connected to a center hole 5 and side holes 6, 7 drilled in each grid 4. An electron gun 9 is formed by alternately fitting the electron beam transmission holes 8 and engagement holes bored in a spacer (not shown).

[0005] Furthermore, conventionally, for example,
As described in Japanese Patent No. 40, a molten insulating glass rod is fixed to the side protrusion of the stacked grid 4 and integrated.

[0006]

On the other hand, since the assembly positional relationship of the grid 4 has a great influence on the performance of the electron gun 9, the accuracy of the positional relationship must be improved.

Further, in the case of the first grid 4 and the second grid 4, for example, the diameter of the electron beam transmission hole 8 is 0.
Since the plate thickness around the electron beam transmission hole 8 is as thin as 0.1 to 0.2 mm, mechanical assembly is extremely difficult.

Furthermore, since it is preferable that the axial arrangement of the electron beam transmission holes 8 be as uniform as possible, the clearance between the diameter of the electron beam transmission holes 8 of the grid 4 and the outer diameter of the center pin 2 is as follows. It is only 0.007 to 0.012 mm, and alignment is practically difficult with normal mechanical assembly accuracy.

In addition, when the precision of press molding is grid 4, the positional precision of the electron beam transmission hole 8 is limited to ±0.03 mm according to the outer shape reference method. Therefore, if only the outer shape of the grid 4 is chucked, the center of the chuck and the center of the electron beam transmission aperture 8 will not exactly match. Therefore, even if an attempt is made to move the electron beam transmission hole 8 to the center pin 2 and insert it, there is a problem in that the deviation is greater than the clearance, making mechanical assembly extremely difficult.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a method for assembling an electron gun for a color cathode ray tube, which allows accurate positioning of parts.

[Configuration of the invention]

0012

[Means for Solving the Problems] A method for assembling an electron gun for a color cathode ray tube according to the present invention is to irradiate a laser beam into a hole in a part of an electron gun for a color cathode ray tube and reflect it at a predetermined position. The component is positioned by moving the component in the X-axis direction, Y-axis direction, and rotationally while detecting the illuminance of the laser beam.

[0013]

[Operation] The present invention irradiates a laser beam into a hole in a component of a color cathode ray tube electron gun and reflects it at a predetermined position, and while detecting the illuminance of the laser beam reflected at the predetermined position, the component is moved in the X-axis direction. By positioning the component by moving it in the Y-axis direction and rotationally, the illuminance will be highest when the component is located at the desired position, so if you stop rotating the component when the illuminance is at its highest position, , positioning can be done easily.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A method of assembling an electron gun for a color cathode ray tube according to the present invention will be explained below with reference to the drawings.

As shown in FIG. 1, the assembly jig 11 of the grid positioning device has a center pin 12 that tapers upward in stages, one side pin 13, and the other side pin 14. . Laser irradiation devices 15 and 16 are provided on one side of the center pin 12 and both side pins 13 and 14 for irradiating laser light downward at an angle of 45 degrees, and on the other side, A light-receiving element that receives laser light irradiated from the laser irradiation devices 15 and 16 and reflected by the center pin 12 or the other side pin 14 and detects the illuminance is arranged downward at an angle of 45 degrees.

[0016] Furthermore, these laser irradiation devices 15, 16
and the light-receiving elements 17 and 18 in the X-axis direction and the Y-axis direction.
A two-jaw chuck body 19 shown in FIGS. 2 to 5 that is axially movable and rotatable is provided. This chuck body 19 includes a center pin 12 and a side pin 1.
It is provided horizontally above the center pin 12 and the side pins 13, 14 at a predetermined distance from the laser irradiation devices 15, 16 on one side of the pins 3, 14.

A grid 20, which is a component of a cathode ray (CRT) electron gun such as a color cathode ray tube, is held in the chuck body 19. Further, this grid 20 is bored with an electron beam transmission hole 24 as a hole portion consisting of a center hole 21, one side hole 22, and the other side hole 23.

Next, the operation of the above embodiment will be explained.

First, as shown in FIG. 2, for example, a straight line connecting the center pin 12 and side pins 13 and 14 and the center hole 21 of the grid 20 held in the chuck body are aligned in a preset X-axis direction. Although the offset distance l is maintained, the centers of the center hole 21 of the grid 20 and the center pin 12 of the assembly jig 11 do not coincide and are deviated by a distance a in the Y direction.

In this state, as shown in FIG. 3, the chuck body 19 is slightly moved along the Y axis. Then, when the chuck body 19 is moved, the illuminance of the laser beam from the laser irradiation device 16, reflected at the tip of the center pin 12 and received by the light receiving element 18, changes according to the position of the center hole 21, as shown in FIG. Change. Then, as shown in FIG. 7, when the center hole 21 of the grid 20 is located in a straight line connecting the laser irradiation device 16 and the tip of the center pin 12, the illuminance becomes the highest peak value, and this peak value is searched. This shows that the center hole 21 has been positioned at a predetermined position, and the fine movement of the chuck body 19 is stopped, and the positioning of the center hole 21 is completed.

Next, as shown in FIG. 4, the grid 20 is rotated by the chuck body 19 around the center hole 21 of the grid 20, the peak value is similarly searched, and the side pin 1 is
At the position where the laser beam from the laser irradiation device 15 reflected at the tip of the chuck body 19 is received by the light receiving element 17 at the peak value of illuminance, the rotation of the chuck body 19 is stopped, and the chuck body 19 is positioned at a position separated by an offset distance l. end. In this state, the center hole 21 and side holes 22 of the grid 20,
23 and the straight line that connects the center pin 12 and side pins 13 and 14 of the assembly jig 11 are parallel. In addition, the positions of the center hole 21 and the side holes 22, 23,
The center pin 12 and the side pins 13 and 14 are located at an offset distance l from each other.

Then, the chuck body 19 is assembled with the jig 11.
A preset offset distance l in the direction of
By moving the center hole 21 and side holes 22, 23 of the grid 20 directly above the center pin 12 and side pins 13, 14 of the assembly jig 11, and vertically lowering the chuck body 19, the grid 20 is moved. The center hole 21 and side holes 22 and 23 of
3 and 14 without any force, and the electron beam transmission hole 24 consisting of the center hole 21 and side holes 22 and 23 is not damaged.

[0023]Therefore, since there is no influence on the center pin 12, the frequency of replacing the center pin 12 of the assembly jig 11 is reduced, and maintenance and management costs of the apparatus can be significantly reduced.

Further, according to the above embodiment, the grid 20
Since positioning is performed by the center hole 21 and side holes 23 of the grid 20,
Electron beam transmission hole 2 consisting of side holes 22 and 23
Even if there is a dimensional error in 4, accurate positioning can be performed, so that productivity can be improved and quality can also be improved.

[0025]

According to the method of assembling an electron gun for a color cathode ray tube according to the present invention, a laser beam is irradiated into the hole of a part of the electron gun for a color cathode ray tube and reflected at a predetermined position, and the laser beam reflected at this predetermined position is X the parts while detecting the illuminance of the light
By positioning the part by moving it in the axial direction, Y-axis direction, and rotation, the illuminance will be highest when the part is located at the desired position, so the rotation of the part will be stopped when the illuminance is at the highest position. By doing so, alignment can be easily carried out, thereby improving productivity and quality.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment of the method of assembling an electron gun for a color cathode ray tube according to the present invention.

FIG. 2 is a plan view showing one step of the positioning operation of the electron gun for the color cathode ray tube.

3 is a plan view showing the next step of the positioning operation of the color cathode ray tube electron gun shown in FIG. 2; FIG.

4 is a plan view showing the next step of the positioning operation of the color cathode ray tube electron gun shown in FIG. 3; FIG.

5 is a plan view showing the next step of the positioning operation of the color cathode ray tube electron gun shown in FIG. 4; FIG.

FIG. 6 is a graph showing the relationship between illuminance and position.

FIG. 7 is an explanatory diagram showing the principle of positioning operation same as above.

FIG. 8 is a perspective view showing a method of assembling a conventional color cathode ray tube electron gun.

[Explanation of symbols]

20 Grid as a component

Claims (1)

[Claims] 1. A laser beam is irradiated into the hole of a component of a color cathode ray tube electron gun, reflected at a predetermined position, and the component is moved in the A method for assembling an electron gun for a color cathode ray tube, characterized in that the parts are positioned by axial and rotational movement.