JP2965673B2 - Manufacturing equipment for shrink-fit type explosion-proof color picture tubes - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to an apparatus for manufacturing a shrink-fit type explosion-proof color picture tube.

(Prior Art) Generally, as shown in FIG. 2, a color picture tube has a substantially rectangular glass panel (2) having a skirt (1) formed in a peripheral portion, and is integrally formed with the panel (2). It has an envelope (4) composed of a funnel-shaped glass funnel (3) joined thereto, and a phosphor screen (5) composed of a three-color phosphor layer is formed on the inner surface of the panel (2). Opposite to the phosphor screen (5), a shadow mask (6) having a large number of electron beam passage holes formed therein is mounted. Also, 3 in the neck (7) of the funnel (3)
An electron gun (9) for emitting an electron beam (8) is arranged. The three electron beams (8) emitted from the electron gun (9) are deflected by a magnetic field generated in a deflection yoke (not shown) mounted outside the funnel (3).
The phosphor screen (5) is formed so as to display an image by scanning horizontally and vertically.

Since the inside of the envelope (4) is evacuated to a high vacuum, the envelope (4) is distorted by the atmospheric pressure, and may be imploded when an external impact is applied thereto. For this reason, explosion-proof means for preventing the implosion have been conventionally used. There are various types of explosion-proof means. Among them, a shrink-fitting method in which a metal ring (11) is attached to the outer periphery of the skirt portion (1) of the panel (2), which is the largest diameter portion, by shrink-fitting is widely adopted. ing. In this shrink fitting method, the metal ring (11) expanded by heating contracts when cooled, and the skirt (1) of the panel (2)
This is an explosion-proof method that tightens the outer periphery.

Conventionally, as shown in FIG. 3, mounting of the metal ring (11) by the shrink-fitting method is performed by protecting a protective tape (1) on the outer periphery of the skirt (1) of the panel (2) of the color picture tube manufactured by a predetermined process. On the other hand, a substantially rectangular annular body (14) having an inner peripheral length shorter than the outer peripheral length of the skirt portion (1) of the color picture tube panel (2) is formed in advance. At the four corners of 14), a metal ring (11) to which a support metal (15) for attaching a color picture tube to a cabinet is formed is formed, and the metal ring (11) is heated and expanded to form a metal ring. Put the above color picture tube protective tape (1) on the body (11).
3) Insert the wound part. Thereafter, the metal ring (11) is cooled, and shrinkage accompanying the cooling is performed to tighten the skirt portion (1) of the panel (2) via the protective tape (13).

As the mounting device for the metal ring (11), the larger the color picture tube becomes, the larger the metal ring (11) becomes, the larger the heat capacity becomes, and high-speed, uniform heating becomes difficult.
An apparatus to which high-frequency induction heating is applied is generally used. FIG. 4 shows the main configuration of the conventional apparatus. This device has a high-frequency induction heating coil (17) which is formed in an annular shape having substantially the same shape as the metal ring, is connected to a high-frequency heating power supply (not shown), and is disposed inside the metal ring. A holding portion (18) for holding the color picture tube with the panel facing downward (on the high-frequency induction heating coil side) is arranged on the heating coil (17). The holding portion (18) has a support plate (19) of an arbitrary shape as a base, and is inclined with respect to a metal ring horizontally arranged outside the high-frequency induction heating coil (17) on the support plate (19). A positioning receiving portion (20) for positioning the color picture tube and a fixing portion (21) for fixing the color picture tube are provided so that the support plate (21) is positioned inside the high-frequency induction heating coil (17). The skirt portion of the panel of the color picture tube held on the support plate (21) is mounted on the operating shaft (23) of the air cylinder (22) which moves up and down by driving the air cylinder (22). It is formed in a structure to be inserted inside the metal ring heated by the high frequency induction heating coil (17).

(Problems to be Solved by the Invention) As described above, the shrink-fitting method widely used as an explosion-proof means for a color picture tube generally forms a metal ring having an inner peripheral length shorter than the outer peripheral length of a skirt portion of a panel. The metal ring is heated by a high-frequency induction heating coil, the skirt of the panel is inserted inside the metal ring, and the outer periphery of the skirt is tightened by cooling and shrinking of the heated metal ring. . However, since the metal ring expanded by heating starts contracting at the same time as the heating is stopped, it is desired that the panel skirt be inserted into the heated metal ring as soon as possible. Therefore, in a device that heats and mounts a metal ring by high-frequency induction heating,
The operation is performed in a state where the color picture tube is held at a position as close as possible to the high frequency induction heating coil for heating the metal ring, and is on standby.

However, when the metal ring is heated while holding the color picture tube close to the high-frequency induction heating coil, the shadow mask mounted inside the panel is relatively thin (typically about 0.15 mm) and many. Since the electron beam passage hole is formed and the heat capacity is small, there is a problem that, when energized, it is heated and deformed by an eddy current generated by a magnetic field generated from the high-frequency induction heating coil.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and in a manufacturing apparatus for a shrink-fit type explosion-proof color picture tube which heats a metal ring by a high-frequency induction heating coil and mounts the metal ring on the color picture tube, An object of the present invention is to prevent a shadow mask mounted inside a panel from being heated by a magnetic field generated from a high-frequency induction heating coil.

[Means for Solving the Problems] A high-frequency induction heating coil for heating a metal ring for tightening the outer periphery of a panel of a color picture tube, and a high-frequency induction heating coil at a position where a magnetic field generated by energization of the high-frequency induction heating coil reaches. In a manufacturing apparatus for a shrink-fit type explosion-proof color picture tube having a metal ring heated by the high-frequency induction heating coil and a holding portion for holding the color picture tube coaxially, the holding portion is attached to the color picture tube. A ferromagnetic member having an outer diameter larger than the outer diameter of the shadow mask, or the outer diameter of a shadow mask mounted on the color picture tube between the holding portion and the high-frequency induction heating coil. A ferromagnetic member having an outer diameter dimension larger than the dimension is arranged, and the thickness of the ferromagnetic member is set to 10 mm or more, and the thickness of the ferromagnetic member is 20
It was positioned 0 mm or more apart.

(Operation) As described above, the holding section is made of a ferromagnetic member having an outer diameter larger than the outer diameter of the shadow mask mounted on the color picture tube, or between the holding section and the high-frequency induction heating coil. A ferromagnetic member having an outer diameter larger than the outer diameter of the shadow mask mounted on the color picture tube is arranged, and the thickness of the ferromagnetic member is set to 10 mm or more, and the ferromagnetic member is positioned at least 200 mm away from the high frequency induction heating coil. This shields the magnetic field generated from the high-frequency induction heating coil when energized, thereby preventing the shadow mask from being heated based on the magnetic field.

Hereinafter, the present invention will be described based on embodiments with reference to the drawings.

FIG. 1 shows a main configuration of an apparatus for manufacturing an explosion-proof color picture tube in which a metal ring is mounted by a shrink fitting method according to one embodiment. This device includes a high-frequency heating power supply unit (not shown),
A high-frequency induction heating coil (30) which is formed in an annular shape having substantially the same shape as the metal ring, is connected to the high-frequency heating power supply unit, and is disposed outside the metal ring; And holding the color picture tube with the panel facing downward (high-frequency induction heating coil side).
1) and a driving device including an air cylinder (34) having the holding portion (31) attached to the tip of an operating shaft (33) penetrating the high-frequency induction heating coil (30).

The holding part (31) is formed in substantially the same shape as the panel of the color picture tube to which the metal ring is mounted (or the shadow mask mounted on the inside thereof), and is smaller than the outer diameter of the panel. The support plate (36), which is larger than the outer diameter of the mounted shadow mask, is used as a base. On this support plate (36), a metal ring placed horizontally inside the high-frequency induction heating coil (30) is mounted. It is provided with a positioning receiving portion (37) for positioning the color picture tube so as not to incline, and a fixing portion (38) for fixing the color picture tube. The support plate (36) is made of a ferromagnetic material such as mild steel having a plate thickness of 10 mm or more. When the metal ring is heated by the high frequency induction heating coil (30), the high frequency induction heating coil (3
It is configured to be located at least 200 mm away from 0).

In this device, a metal ring is arranged inside a high-frequency induction heating coil (30), and a color picture tube in which a protective tape is wrapped around the outer periphery of a skirt portion of a panel is attached to a holding portion (31) with the panel facing downward. Position and fix. Then, after the metal ring is heated and expanded by energization from the high-frequency heating power supply unit, the holding unit (18) is lowered by driving the air cylinder (34), and the winding portion of the protective tape of the color picture tube is wound as described above. This is performed by inserting the metal ring inside the heat-expanding metal ring. The wound portion of the inserted protective tube of the color picture tube is clamped by the metal ring which contracts by cooling.

By the way, as described above, the support plate (36) of the holding portion (31) for holding the color picture tube is formed of a ferromagnetic member having a plate thickness of 10 mm or more, and the metal ring is heated by the high-frequency induction heating coil (30). When the high frequency induction heating coil (30)
If the distance is more than 200 mm, the magnetic field generated by the energization of the high-frequency induction heating coil (30) is shielded from the shadow mask inside the panel of the color picture tube that is held and fixed by the holding part (31). The mask can be prevented from being heated, and the shadow mask can be prevented from being heated and deformed when the metal ring is heated by high-frequency induction heating. Moreover, if the holding part (31) is made to have a plate thickness of at least 10 mm and separated from the high-frequency induction heating coil (30) by at least 200 mm, the temperature rise of the holding part (31) can be suppressed, and the metal ring is heated and mounted. Can be repeated.

In the above embodiment, the holding portion for holding the color picture tube was formed of a ferromagnetic member having a plate thickness of 10 mm or more.However, the holding portion was formed of an arbitrary material, and was provided between the holding portion and the high-frequency induction heating coil. A high-frequency induction heating coil made of a ferromagnetic member having a thickness of at least 10 mm, which is formed in substantially the same shape as the panel of the color picture tube, is smaller than the outer diameter of the panel, and is larger than the outer diameter of the shadow mask mounted inside the panel. From 200mm
The same effect can be obtained even if they are separated from each other.

[Effect of the Invention] In an apparatus for manufacturing an explosion-proof color picture tube in which a metal ring is mounted by shrink-fitting, a holding portion for holding the color picture tube coaxially with the metal ring heated by the high-frequency induction heating coil is provided. A ferromagnetic member with an outer diameter larger than the outer diameter of the shadow mask mounted on the color picture tube,
Alternatively, a ferromagnetic member having an outer diameter larger than the outer diameter of the shadow mask mounted on the color picture tube is arranged between the holding unit and the high-frequency induction heating coil, and the thickness of the ferromagnetic member is set to 10 mm or more. As a structure that is positioned at a distance of 200 mm or more from the high-frequency induction heating coil, the ferromagnetic member shields the magnetic field generated from the high-frequency induction heating coil when energized, preventing the shadow mask from being heated and deformed due to the magnetic field. can do.

[Brief description of the drawings]

FIG. 1 is a diagram showing a main configuration of an apparatus for manufacturing an explosion-proof color picture tube to which a metal ring is mounted by a shrink fitting method according to an embodiment of the present invention, and FIG. FIG. 3 is a view for explaining an explosion-proof method of a color picture tube by a shrink-fitting method, and FIG. 4 is a diagram showing a main part of an apparatus for manufacturing an explosion-proof color picture tube in which a metal ring is mounted by a conventional shrink-fitting method. FIG. 3 is a diagram illustrating a configuration of a unit. 30 high frequency induction heating coil 31 holding part 34 air cylinder 36 support plate 37 positioning receiving part 38 fixed part

Claims (1)

(57) [Claims] 1. A high-frequency induction heating coil for heating a metal ring for tightening the outer periphery of a panel of a color picture tube, and a high-frequency induction heating coil is heated to a position where a magnetic field generated by energization of the high-frequency induction heating coil reaches. In a manufacturing apparatus for a shrink-fit type explosion-proof color picture tube having a metal ring and a holding portion for holding the color picture tube coaxially, an outer diameter of a shadow mask having the holding portion mounted on the color picture tube A ferromagnetic member having a larger outer diameter, or a ferromagnetic member having an outer diameter larger than the outer diameter of a shadow mask mounted on the color picture tube between the holding portion and the high-frequency induction heating coil. Wherein the ferromagnetic members have a thickness of at least 10 mm and are located at least 200 mm away from the high-frequency induction heating coil. -Picture tube manufacturing equipment.