JPH0482130A - Reinforcement of cathode-ray tube - Google Patents

Abstract

PURPOSE:To shorten the time for adjusting a deflection yoke by controlling the current to run in a reinforcing band directly before heating is finished gradually, or in a continuous slope-down mode. CONSTITUTION:An elevating board 5 is started under a condition that a board 2 for putting a cathode-ray tube and a transformer 12 are lowered. An upper core 14d of a core 14 is moved to the right hand side, while the upper part between a primary side core 14a and a secondary side core 14c, is opened. In this state, a mounting lug 10a of a reinforcing band 10 is positioned and put on a lug receiving block 11. The elevating board 5 is then lifted, thus the transformer 12 is lifted, while a part of the reinforcing band 10 is positioned between the primary side core 14a of the core 14 and the secondary side core 14c. A core opening/closing cylinder 19 is then actuated, and the upper core 14d is proceeded and the core 14 is closed. A cylinder 17 for pushing up the core is then actuated, and a rod 18 is lowered, while the upper core 14d is closely sticked to the primary side core 14a as well as to the secondary side core 14c.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a method for reinforcing a cathode ray tube, in which a frame-shaped reinforcing band is heated by passing an electric current through it, and the reinforcing band is attached and fixed to the outer periphery of the face of the cathode ray tube by shrink fitting. In particular, the present invention relates to a method of heating a reinforcing band.

[Conventional technology]

In a conventional method for reinforcing a cathode ray tube by shrink fitting, for example, as shown in Japanese Unexamined Patent Application Publication No. 59-173935, the reinforcing band is fully heated by directly applying electricity from the metal part of the reinforcing band.

[Problem to be solved by the invention]

The above-mentioned conventional technology does not take into consideration the fact that the reinforcing band is magnetized by energization for heating the reinforcing band. Therefore,
After reinforcement, the reinforcing band was demagnetized using a demagnetizing coil, but there were problems in that it was not completely demagnetized and it took a lot of time to adjust the deflection yoke.

An object of the present invention is to provide a method for reinforcing a cathode ray tube that can prevent magnetization of a reinforcing band.

[Means to solve the problem]

In order to achieve the above object, the current flowing through the reinforcing band is controlled by slowing down stepwise or continuously before the heating ends.

[Effect]

If the slow cathode ray tube receives the electric current R stepwise or continuously before the end of heating, the induced back electromotive force generated at the end of heating can be prevented, and magnetization of the reinforcing band can be prevented.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

As shown in FIG. 1, on a cathode ray tube mounting table 2 on which the cathode ray tube 1 is placed, there are provided a suction cup 3 and a cathode ray tube holder 4 for sucking and fixing the cathode ray tube 1. The cathode ray tube mounting table 2 is fixed to the upper end of a center shaft 6 which is rotatably supported by a lifting table 5. The lifting platform 5 is provided so as to be movable up and down along a vertically arranged guide rod 7, and is moved up and down by a vertical cylinder 8.

The fixed part 9 of the device is provided with a lug receiver block 11 that receives a mounting lug 10a provided on the reinforcing band 10. Further, a heating transformer 12 for heating the reinforcing band 10 is provided on the lifting platform 5.

The transformer 12 has a primary winding 13 as shown in FIG.
and a core 14, and the primary winding 13 is connected to a transformer control power source 15, which is placed separately from the device, with a flexible connecting cable 16. The core 14 has a primary core 14a, a lower core 14b, and a secondary core 14c integrally formed. It is separated from the side core 14b and is a separate body, and is slidably provided.

Returning to FIG. 1 again, inside the lifting platform 5 is a transformer 1.
A core pushing cylinder 17 is provided to push up the upper core 14d of the cylinder 1.
It is pushed up by a rod 18 which is moved up and down by a rod 7. Also, on the fixed part 9 of the device, there is a core opening/closing cylinder 1 for sliding the pushed-up upper core 14d.
9 is provided via a stand 20.

Next, the operation will be explained. First, the process starts with the lifting table 5 being lowered, that is, the cathode ray tube mounting table 2 and the transformer 12 being lowered. In this state, the core 14 is open, that is, the upper core 14d has moved to the right, and the upper portion between the primary core 14a and the secondary core 14c is open.

In this state, the lug holder is attached to the reinforcing band 10 on the block 11.
For installation, position and place the lug 10a.

Next, the lifting platform 5 rises, that is, the transformer 12 rises, and a part of the reinforcing band 10
It is located between the next cores 14c. Thereafter, the core opening/closing cylinder 19 is activated, and the upper core 14d moves forward to move the core 14
is closed. Subsequently, the core lifting cylinder 17 is operated to lower the rod 18, and the upper core 14d comes into close contact with the primary core 14a and the secondary core 14c. Thereafter, the cathode ray tube 1 is supplied and placed on the cathode ray tube receiver 4, and the cathode ray tube 1 is positioned by a positioning mechanism (not shown). The direct air suction of the suction cup 3 works, and the cathode ray tube 1 is reliably held.

As mentioned above, the upper core 14d is connected to the primary cores 14a and 2.
When a voltage is applied to the primary winding 13 of the transformer 120 after being in close contact with the next core 14c, a magnetic field is generated in the core 14, and the reinforcing band 10 acts as a secondary winding. This is from K.
An induced current flows uniformly over the entire circumference of the reinforcing band IOK, and the reinforcing band 10 is heated and expanded uniformly over the entire circumference without uneven heating or heating temperature difference. Due to this heating, the inner circumference of the reinforcing band 10 becomes longer than the outer circumference of the face of the cathode ray tube 1.

Furthermore, before the heating ends, as shown in FIG. 3, the current supplied to the primary winding 13 is slowed down stepwise 21 or continuously 22. This prevents an induced back electromotive force at the end of heating, and prevents the reinforcing band 10 from being magnetized. At the same time, the reinforcing band 10 that was magnetized during assembly and welding is also demagnetized.

After the reinforcing band 10 is sufficiently heated in this way, the current flow to the transformer 120 is slowed down and stopped, and at the same time, the core lifting cylinder 17 is operated in the opposite direction to raise the rod 18. As a result, upper core 1
4d is separated from the primary core 14a and the secondary core 14c. Subsequently, the core opening/closing cylinder 19 is operated in the opposite direction to the above, and the upper core 14d'i is slid. As a result, the upper part of the reinforcing band 10 is opened. Thereafter, the lifting table 5, that is, the transformer 12 and the cathode ray tube mounting table 2 are immediately lowered to insert the cathode ray tube 1 into the reinforcing band 10. Then, the reinforcing band 10 is cooled by a cooling means (not shown). As a result, the reinforcing band 10 is contracted and fixed to the outer periphery of the face of the cathode ray tube 1.

In the above embodiment, the method of slowing down the current applied to the reinforcing band 10 before the end of heating is applied to the method of heating the reinforcing band 10 by making the reinforcing band 10 act as the secondary winding of the transformer 120. Although the case described above is described, it is of course applicable to a method of heating the reinforcing band by directly passing an electric current through the reinforcing band as in the conventional example.

〔Effect of the invention〕

According to the present invention, it is possible to prevent the induced back electromotive force at the end of heating the reinforcing band, so it is possible to prevent the reinforcing band from being magnetized, and at the same time, it is possible to demagnetize the magnetized during the assembling and welding of one reinforcing band during heating. I can do it. This eliminates the need for a reinforced degaussing coil and shortens the deflection yoke adjustment time.

[Brief explanation of drawings]

Fig. 1 is a front view of a reinforcing device for a cathode ray tube used in an embodiment of the present invention, Fig. 2 is a schematic perspective view of a heating transformer, and Fig. 3 is a heating time diagram showing an embodiment of a control method of the present invention. It is a relationship diagram of electric current. 1.- Braun tube, 10... Reinforcement band, 12
...transformer, 21...stepwise slowdown, 22...continuous slowdown. Figure 1 Figure 2 Q Near sedentary j゛〉k = 2 = Tounce Figure 3 1: Braun tube O: Ne ゛ Strong! %:・N V・ 2 Nidorance 61-21: Dan Sieve] Lis O-Dedakun 22: Speed] Seven system slope town

Claims (1)

[Claims] 1. In a method for reinforcing a cathode ray tube, in which a frame-shaped reinforcing band is heated by passing an electric current through it, and this reinforcing band is attached and fixed to the outer periphery of the face of the cathode ray tube by shrink fitting, the current flowing through the reinforcing band is applied before the end of heating. A method of reinforcing cathode ray tubes characterized by stepwise or continuous slowdown control.