KR910005477B1 - Electrode thermometric device of cathode ray tube manufacturing - Google Patents

Abstract

The method measures variable temperatures of electrodes including the cathode prepared for heating in processes of aging or gas evacuation accurately. A connecting point of a thermocouple is attached to a certain electrode at a dummy tube for measuring temperature. Each terminal of the thermocouple is respectively connected to the inner stem lead at the dummy tube. The interspace between the outer-projected stem lead at the dummy tube and the temperature recorder, is connected by the same material as thermocouple wire. Temperatures of electrodes are displaged on the recorder directly because an electric current from the electrode temperature is transferred to the thermocouple wire.

Description

Method of measuring electrode temperature during cathode ray tube manufacturing process

In accordance with the present invention attached is a view for explaining a measuring method during the manufacturing process of the cathode ray tube.

* Explanation of symbols for main parts of the drawings

1: first electrode 2: second electrode,

3a, 3b, 3c: third electrode 4: fourth electrode,

5: bead glass 8: stem lid

10: dummy tube RA, RB ： temperature recorder

_{L 1,} L _2: thermal election K: negative,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring electrode temperature during a cathode ray tube manufacturing process, and more particularly to a method for accurately measuring the temperature of various electrodes including a cathode to be heated during an exhaust process and an aging process.

In general, the manufacturing process of a television CRT is (1) a screen manufacturing process of applying a fluorescent film to a valve and fixing a frame equipped with a shadow mask in the case of a color CRT, and (2) a plurality of electrode parts in a line. (3) The process of manufacturing the electron gun mount fixed in the step (EMEM) and fixed to the step (EMEM), the process of enclosing the said electron gun mount in the bulb of a CRT, and (4) the above-mentioned pyrolysis decomposed on the cathode of the electron gun. An exhausting step of discharging air from the enclosed bulb, (5) a step of aging the above-described CRT, and (6) a test step of examining the electrical characteristics of the aged CRT.

As is well known, the CRT is a device that emits light by colliding electrons accelerated with a high voltage to a phosphor of a screen in a certain amount. It should be possible to sufficiently overcome stray emission and the like, while maintaining the electron emission characteristics from the cathode uniformly.

In general, the carbonate with an electron-emitting function is applied to the cathode in the electron gun of the cathode ray tube is either in a three wonyeom of _{BaSO 3, SrCO 3, CaCP 3} , it is known to manufacture aluminum by sedimentation or precipitation beopdeung soda. When heat is applied to this carbonate, thermal decomposition of the carbonate occurs, and the oxide resulting from the pyrolysis performed in the exhaust process becomes a semiconductor, so that free atoms can be generated and released by an activating operation by an aging process described later.

In the above-described CRT manufacturing process, the aging process is performed to obtain stable electron emission characteristics and luminescence characteristics, which are divided into three types.

That is, first, an aging aging that generates a glass atom by activating a carbonate coated on the cathode by flowing a current to the cathode to release a certain amount of electrons from the cathode, and second, a discharge due to foreign matter incorporated into the bulb during the manufacturing process, In order to exclude high voltage phenomena such as fluorescence and stray emission, a high voltage aging is applied to the anode and a high voltage aging is used to clean foreign substances on each electrode. In order to stabilize the emission characteristics, a predetermined voltage is applied to the cathode to perform raster aging that activates the cathode while displaying a raster on the screen.

As shown above, in the manufacturing process of the cathode ray tube, particularly in the exhaust process and the aging process, it is necessary to accurately maintain the temperature of the cathode and each electrode at a predetermined value.

In the manufacturing process of such a cathode ray tube, the temperature of various electrodes including a cathode to be managed varies depending on the type and dimensions of the cathode ray tube to be manufactured.

Therefore, until now, as the basic work for mass production of a new electron gun, the characteristics of each electrode of the electron gun are checked during the process, and the temperature measurement of the electrode is performed by measuring the temperature. It has been done using a pyrometer which is well known as a device. More specifically, this temperature measuring method is not to actually measure the temperature of the electrode during the manufacturing process of the dummy tube under test, particularly during the exhaust and aging processes, and once the dummy tube has been manufactured. The process conditions could not be set depending on the expected values using the temperature characteristic curves for the voltages and currents applied to each electrode. It was difficult to establish.

Accordingly, the present invention has been made in order to solve the above problems, and provides a method for directly measuring the exact electrode temperature during the manufacturing process of the dummy tube to measure the accurate cathode temperature during the development of the three-pole portion of the electron gun. It aims to set the correct temperature conditions for the electrodes in the exhaust and aging process and to improve the emission characteristics of other cathodes.

According to the method of the present invention for achieving the above object, a stem lead having a junction point of a thermocouple wire attached to a predetermined electrode of a dummy tube to be measured, and the other terminals of the thermocouple wire being inside the dummy tube. The temperature of each electrode can be directly taken out of the thermocouple wire in the form of a current by connecting between each stem lead and the temperature recorder protruding out of the dummy tube and the temperature recorder. It is characterized by that.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In the figure, reference numeral 10 denotes a dummy tube under test, which consists of only a portion corresponding to the neck portion of a normal cathode ray tube. That is, the stem 7 is integrally attached to the lower side of the dummy tube 10, and a plurality of leads 8 protruding into the inner and outer sides of the tube are embedded in the body of the stem 7. Inside the pair of bead glass 5, a cathode K, a first electrode 1, a second electrode 2, a third electrode 3a, 3b, 3c, and a fourth electrode 4 are formed. In order to be fixed at regular intervals, a bulb spacer 6 is mounted to maintain a constant interval between the electron gun and the tube wall of the tube.

In the accompanying drawings, a configuration for measuring the temperature of the cathode and the second electrode 2 is connected, the temperature of the cathode is the recorder Ra, the temperature of the second electrode 2 is the recorder ( Rb). To explain more detailed connection state, the junction point of the thermocouple wire L ₁ (L ₂ ) is attached to the cap portion of the cathode by welding, and the thermocouple wire L ₁ (L ₂ ) The other terminals are welded to one end of the stem leads 8a and 8b, respectively. And by connecting the step leads (8a) (8b) and the other terminal and a recording system (Ra) above thermal election (L ₁₎ (L ₂₎ and the material of the heat-election _{(L 1 ') (L 2} ') , such as between the In fact, the configuration for measuring the cathode temperature is completed.

Under such a configuration, the temperature of the cathode due to the heat applied to decompose the carbonate of the cathode in the exhaust process appears in the form of a current in the thermocouple line L ₁ (L ₂ ), which is the thermocouple line L ₁ ′ (L ₂ ′). In the aging process, the temperature of the cathode can be measured while applying an electrical signal to the filament of the cathode through the line 9 connected to the step lead 8c. It is supposed to be.

As can be seen from the above, according to the present invention, since the electrode temperature of the electron gun can be directly measured during the manufacturing of the dummy tube during the development of the cathode ray tube, it is possible to establish accurate fixing conditions. The way has been opened that can be performed accurately and easily.

Claims (1)

The junction point of the thermocouple wire is attached to a predetermined electrode of the dummy tube to be measured, and the other terminals of the thermocouple wire are respectively connected to the stem lid inside the dummy tube, while each stem lead and the temperature protruding out of the dummy tube are measured. A method of measuring electrode temperature during the manufacturing process of a cathode ray tube, characterized in that the recorder is connected by a line of the same material as the above-mentioned thermocouple line to take out the temperature of each electrode directly in the form of a current to the thermocouple line and display it on the recorder. .

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