JPS58172845A - Activation process for electrode substance - Google Patents

Abstract

PURPOSE:To uniformly activate the electron emission substance which is spread on the electrode of a discharge lamp without enclosing mercury, by using in parallel, the electric conductive heating and activation caused by discharge between the both ends of an electrode in inert gas. CONSTITUTION:An electrode 3 of a discharge lamp is coated with electron emission substance E made of ternary carbonate. When this substance E is activated with ternary oxide, the electrode 3 is energized by means of a power source 2 and a current limiting resistance 5, while the inside of a glass bulb 1 is exhausted, and the substance E is thermally decomposed. In this case, the current is adjusted so as to properly activate a central part A. At the time when CO gas and CO2 gas produced through this activation are almost exhausted, inert gas is enclosed in the bulb 1 through an exhaust pipe 4, and a high-frequency pulse voltage is impressed on both ends 3a, 3b of the electrode 3. Thereupon, the discharge is produced, the both ends B, B are heated, and the inactivated parts of the substance E are activated. Next, the produced impure gas and the enclosed inert gas are exhausted.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for activating an electron radioactive substance applied to an electrode of a discharge lamp.

The electron radioactive substances that can be applied to the electrodes are usually barinium carbonate (Ba CO3), stroncherum carbonate (SrC
O3), calcium carbonate (CaCOa), a so-called ternary carbonate, and may further contain a metal such as zirconium oxide (ZrOλ). Activation of the electron radioactive substance during production involves thermally decomposing the above ternary carbonate to produce barinium oxide (BaO) and strontium Mide (S), respectively.
r O) Refers to the process of converting into an oxide called calcium oxide (CaO).

Conventionally, as a heating means, electricity is applied to an electrode coated with the above-mentioned electron radioactive substance to reach a temperature of 1000 to 1300°C.
The decomposition temperature was reached. That is, as shown in FIG. 1, during the evacuation process inside the glass tube l, electricity is applied to both electrodes 3, 3 made of filaments by the power source 2, and Co, COz, etc. generated by thermal decomposition are passed through the evacuation pipe 4 and pumped ( (not shown) was used to exhaust the air outside the pipe. Note that 5 in the figure is a current control resistor.

However, in such an activation method using electrical heating, as shown in FIG. Because B and B dissipate heat and become in a stable state, the temperature of both sides B and B was lower than that of the center part A. Therefore, even if the electron radioactive substance E in the center part A could be activated properly, The electron radioactive substance E at both ends B and B remains in an inactive state, and as the electron radioactive substance E in the inactive state gradually decomposes during lighting, the impurity gas concentration in the glass tube 1 is reduced. In addition, in order to properly activate the electron radioactive material E at both ends B and B, the electron radioactive material E at the center part A must be activated. The activity became excessive, excessive free variem was produced, and the electron radioactive substance E evaporated during lighting, resulting in early blackening and shortened lifespan.

In order to improve this drawback, a method has been adopted in which mercury is once sealed inside the tube after electricity is applied, and electricity is applied again to cause a discharge to occur between both ends of the electron radioactive material coated part, thereby activating both ends.

However, in this method, mercury is contained in the exhaust gas components, which may cause environmental pollution, and thus cannot be said to be a preferable method.

The present invention was made to improve the above problems,
The purpose of this is to provide a method for uniformly activating the electron radioactive material applied to the electrodes during the manufacture of discharge lamps without the need for encapsulating mercury. , the present invention will be explained based on examples. 3 are process diagrams showing an embodiment of the method for activating an electrode material according to the present invention. (1) First, electricity is applied to the electrode 3 to activate the electron radioactive material E in the same manner as in the conventional method. The magnitude of the current at this time is maintained at a value that appropriately activates the central portion A shown in FIG.

■ Impure gas (C0C02) generated by the above activation
When the evacuation of the glass tube 1 is almost completed, argon A is added to the glass tube 1.
An inert gas such as R is sealed through the exhaust pipe 4.

(2) Next, by applying a high-frequency pulse voltage as shown in FIG. 4 to both ends 3a and 3b of the electrode 3, a discharge is caused between both ends 3a and 3b, and both ends B shown in FIG. , B to activate the unactivated components of the electron radioactive substance E. The peak value of the pulse voltage at this time is
The ionization voltage must be higher than the ionization voltage of the enclosed inert gas.

(2) The impure gas generated in (2) above and the enclosed inert gas are exhausted to complete the activation process of the electron radioactive substance E. In addition,
Exhaust may be performed at the same time as the above ①.

In this way, applying a commercial frequency wave to the electrode 3 in an inert gas is because the ionization voltage of the inert gas is high, and simply increasing the applied voltage using direct current or commercial frequency alternating current will cause the voltage to be applied to the electrode 3 before discharge occurs. This is because ficimen 1 current becomes excessive and the activity becomes excessive. That is, by applying a pulsed voltage, both ends 3a and 3b of the electrode 3 are
The purpose is to facilitate the discharge between the two ends, to allow the discharge to occur without overactivating the central portion A, and to bring the both end portions B, B into an appropriate activation state.

In addition, the application of the iii frequency pulse voltage in the above ① is as follows:
As shown in Figure 5, positive pulses are applied continuously in the first half,
Negative pulses may be applied continuously in the latter half. In such a case, for the electron radioactive substance E at both ends B and B of the electrode 3,
In the first half and second half, a hot spot is formed only for one end B and each end B is activated,
There is almost no substantial difference compared to the above embodiment, and when the configuration of the power source 2 is taken into consideration, there is an additional effect that it is only necessary to change the polarity of the DC pulse power source between the first half and the second half.

As mentioned above, the method for activating an electrode material according to the present invention includes:
It is characterized by the combination of the first activation by electrical heating and the second activation by generating a discharge between both ends of the electrode in an inert gas, so that the electron radioactive substance applied to the electrode can be uniformly applied. , and can be activated appropriately, improving lamp characteristics and lamp life.Moreover, since mercury is not used, the exhaust components do not contain harmful substances such as mercury, and there is no risk of causing environmental pollution. Furthermore, since the inside of the tube can be cleaned (flushing) with an inert gas and the activation step can be performed at the same time, there is an additional effect that the number of steps and the manufacturing time can be reduced.

[Brief explanation of the drawing]

Figure 1 is a simplified diagram showing a conventional example, Figure 2 is an enlarged diagram of the electrode,
FIGS. 3-3 are process diagrams showing one embodiment of the method for activating an electrode material according to the present invention, and FIGS. 4 and 5 are high-frequency pulse voltage waveforms applied between both ends of the electrode, respectively. Patent Applicant Matsushita Electric Works Co., Ltd. Agent Patent Attorney Toshimaru Takemoto Two idiots Figure 1 Figure 2 AB Figure 3 Figure 4FgJ Procedural Amendment (August 6, 1981 Commissioner of the Japan Patent Office, Mr. 16 Case) Indication 1982 Patent Application No. 054293 2, Title of the Invention 11 - - Ga-gon's ηΔ Raw Ishisho Law 3, Incident with Person Who Makes Amendment Residence: Kadoma City, Osaka Prefecture Oaza Kadoma 1048 Address Name (583) Matsushita Electric Works Co., Ltd. Representative Iku Kobayashi 4, Agent Address 1048-5 Oaza Kadorashi, Kadoma City, Osaka Prefecture [84 Sun of Positive Orders] July 27, 1980 (
Shipping date) 6. Subject to correction □. Brief description of the drawings in the specification, drawing 7, contents of amendments 1) "Figures 3 - 3 show electrode materials according to the present invention, from page 6, line 20 to page 7, line 1 of the specification. Figures 18) to (C) are process diagrams showing an example of the method for activating an electrode material according to the present invention; al is the activation process of the central part of the electrode A, (bl is the exhaust process, (C1 is the activation process and exhaust process of the electrode ends B, B, etc.). 2) Figure 3 of the drawing is shown in the attached sheet. (The part that can be marked in red on the attached drawing). Figure 3 Procedural amendment (Haruyama 1. Indication of the incident ls) 1957 Patent application No. 054293 2, Title of invention Method 3: Relationship with the person making the amendment Patent applicant address: 1048 Kadoma, Kadoma City, Osaka Name (583) Matsushita Electric Works Co., Ltd. Representative: Iku Kobayashi 4, Agent address: Kadoma City, Osaka Prefecture Detailed description of the invention column 6 of the 1048 Kadoma Oaza specification, contents of amendment 1) “Fig. 2) Insert ``(See Figure 3 1a)'' after ``Keep at...'' on page 4, line 8 of the specification. 3) Specification Insert "(See Figure 3 (b))" after "...will be enclosed." on page 4, line 12 of the book. 4) Insert [(see Figure 3 fcl)] after "..." on page 4, line 20 of the specification. 5) Insert "(See Figure 3 (C1)" after "...mayi." on page 5, line 4 of the specification. 185

Claims (1)

[Claims] (1) In activating the electron radioactive substance applied to the electrodes of a discharge lamp, the first activation by heating with electricity and the second activation by generating a discharge between both ends of the electrode in an inert gas were used together. A method for activating an electrode material, characterized in that: