JPS61214324A - Thermion emission structure - Google Patents

Abstract

PURPOSE:To firmly connect the heater and the tab of a thermion emission structure together by constituting the heater from a first filament made of tungsten or similar material which has a coil and legs and second filaments having a lower melting point than the first filament which are attached to the legs. CONSTITUTION:A thermion emission structure for an electron tube includes a heater 13 which is installed in a cylinder 12 and used to heat a cathode base 11 containing a thermion emission substance. The heater 13 is made by fusing a first filament made of tungsten or similar material which has a coil and legs and second filaments made of platinum or similar material having a lower melting point than the first filament which are attached to the legs of the first filament by resistance welding or a similar method. The legs of the first filament are welded to a heater tab made of platinum or similar material by laser to supply current to the tab. Therefore, the first and the second filaments and the heater tab are firmly bound together to form an alloy having a lower melting point, thereby improving the reliability of the thermion emission structure.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to improvements in four thermal screw discharges for magnetonite tubes.

[Technical background of the invention and its problems]

The four thermal screw emitters have a heater test for heating the shade substrate containing the thermionic emissive material. For example, in the indirect heating type thermal abrasive emitting manual, as shown in Figure 4, the ls substrate (1) having a thermal abrasive emitting substance is placed in the heater wire (5 ), the heater wire (5) is brought into contact with the heater tab (6) and current is supplied.

The heater tab (6) is usually made of nickel alloy or molybdenum, and the heater wire (5) is laser welded.

They are joined by methods such as resistance welding, l14L beam welding, or arcing (TIG welding).

Since the connection between the heater wire (5) and the heater tab (6) is made by bath welding of tungsten and nickel alloy or molybdenum, one point is high and sometimes the bond is incomplete. It has the drawback of impairing the reliability of a single tube using a discharge structure.

[Purpose of the invention]

The object of the present invention is to provide a stronger and more reliable joint between the heater wire and the heater tab, and to provide four highly reliable thermal screws.

[Summary of the invention]

The present invention consists of a base body having four heat screws discharging, a shadow r* seat that supports this original base body at one end C2, a heater that is housed within the base body and heats the base base body, A thermal screw release 4 comprising a heater tab for fixing this heater.
In the present invention, the heater includes a first filament made of tungsten or a tungsten alloy having a coil shape and a leg portion, and a leg portion of the first filament (= an attached metal strip having a lower melting point than the first birch strip). and the first and second filaments are alloyed and fixed to a heater tab by a tethering means. As the heat 1 maple emission body of the first investigation above (
= around the 1st fi and 42 filaments (= strong (== 3 filaments made of wound tungsten or tungsten alloy or molybdenum or molybdenum alloy are added, and each of these filaments and the heater tab By welding and fixing these wires, the melting point of the alloy phase is lowered to obtain a more solid bond.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

Fig. 1 shows the cylindrical structure of this embodiment.
The upper end of J (; the gap substrate υ which is connected to the fitting bath, and the heater (1'5 housed in the shade cylinder) for heating this gap substrate, and which holds this heater u'5 Therefore, it consists of an insulating filler material filled in the hollow cylinder.

Therefore, the heater has a diameter of 0, for example, as shown in Figure 2.
．． The first filament (13 legs) consisting of a 35 mu 97% W-3% Re wire (= diameter of 0.0 mm with a lower melting point than this W-R wire).
A second filament I made of a 2n platinum wire is attached.

The first and second filaments are fixed by, for example, an electric resistance bath contact C2.

This heater is made of aluminum oxide 44, including a part of the leg part, and is incorporated as a heater-embedded heater for an impregnated disk heat-on emitting structure as shown in Figure iIf&1.

The structure thus obtained is in contact with a heater tab made of platinum having a thickness of 0.05 all and a width of 10 am, for example, and a laser beam near the end of the heater leg, thereby forming a heat-emitting tube.

The first filament, the second filament, and the heater tab exhibit an alloy phase having a melting point higher than the melting point of their respective materials, and a strong bond can be obtained.

However, the connection between the heater tab of such a thermal gluing structure and the
Single strength? Test or make a heater test like the one shown in Figure 4. This heater test tube is equipped with a glass envelope (4υ), a platinum heater tab (6) joined to the heater leg, and a companion lead Nt431 that carries the heater tab (=4) to 14. It's still fever 1
The child emission structure is either pre-bonded with a platinum heater tab or the inside of the envelope (4υ) is evacuated.

Now, as a method to test the strength characteristics of the bath contact part of the heater leg of the heat dissipation structure manufactured in this way, Table 1 shows the results of a frequency sweep type forced vibration test next month (; show.

For comparison, a conventional heater leg and heater tab were also tested (= provided) by laser welding.

Further, in both this embodiment and the conventional heater wire, a 97% W-3% Re heater wire has a diameter of 0.35 mm.

As is clear from Table 1, the four hot abrasive dischargers of this example can completely eliminate the occurrence of welding defects.

The third embodiment of the second invention according to the present invention will be described below.
This will be explained with reference to the figures. Figure 3 shows the heater,
Parts that are the same as those in the figures are given the same reference numerals.

In this embodiment, a 97% W-3 Re wire having a diameter of 0.01 mm is tightly wound around the circumference of the first and second wires.

After assembling such a heater into four thermal abrasive units, we made a test tube similar to the one shown in Figure 4 above, and conducted a frequency sweep type forced vibration test next month.The results were as follows: .

It is clear from this trial result that the intensity of compensation is the same as above.

In addition, in the above 2% example, the platinum wire kIeV is used as the second linear power.
Examples using other than mountain sparrows are shown, but rhenium (Re),
/rethenium (Ru), molybdenum (Mo), palladium (Pd). It has been confirmed that similar effects can be obtained using any metal such as iridium (Ir) or tantalum (Ta) or an alloy thereof.

Further, although an example has been described in which laser welding is used as a means for welding and fixing the 41i to 3rd filament and the platinum heater tab, it is of course possible to apply other welding means such as single resistance welding, TIG welding, etc.

In addition, the present invention is also applicable to both the impregnated type and the indirectly heated type.
Although the above description has been made regarding IK, the present invention is not limited to this, and can also be applied to direct heating type dark structures.

〔Effect of the invention〕

As described above in the examples, the thermocling discharge structure according to the present invention has a strong contact strength with the heater tab at the heater leg (=69), and the vibration is abnormal. It is possible to obtain a highly reliable waste material suitable for use in commonly used impregnated dust gap structures, box structures for aircraft or vehicle-mounted display tubes, and the like.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an indirect heat-induced eruption body according to the present invention ζ2,
lt&2 is an explanatory diagram showing an indirectly heated type heater for anode according to the present invention, Figure 3 is an explanatory diagram showing an indirectly heated type heater for anode according to the second invention (Fig. FIG. 5 is a conceptual diagram showing a heater test according to an embodiment, and FIG. 5 is a sectional view showing a conventional indirectly heated shade structure.

Claims (4)

[Claims] (1) A cathode base having a thermionic emission substance, a cathode cylinder supporting the cathode base at one end, a heater housed in the cathode cylinder and heating the cathode base, and a heater tab that keeps the heater constant. In the thermionic emission structure, the heater includes a first filament made of tungsten or a tungsten alloy having a coil shape and a leg, and a first filament attached to the leg of the first filament and extending from the first filament. a second filament made of a low melting point alloy;
A thermionic emission structure characterized in that the filaments are alloyed by a heater tab and a welding means. (2) In claim 1, the second filament is a metal selected from the metals platinum, ruthenium, palladium, iridium, molybdenum, tantalum, and rhenium, or an alloy containing the metal as a living body, and A thermionic emission structure characterized in that the heater tab is made of platinum. (3) A cathode base having a thermionic emission material, a cathode cylinder supporting the cathode base at one end, a heater housed in the cathode cylinder and heating the cathode base, and a heater tab fixing the heater. In the thermionic emission structure, the heater includes a first filament made of tungsten or a tungsten alloy having a coil shape and a leg, and a first filament attached to the leg of the first filament and having a height lower than the first filament. a second filament made of an alloy with a melting point; and a third filament made of tungsten or a tungsten alloy, molybdenum or a molybdenum alloy, tightly wound around the first filament and the second filament. . A thermocling emitting structure, characterized in that the first to third filaments are alloyed by welding with a heater tab. (4) In claim 3, the second filament is a metal selected from the metals platinum, ruthenium, palladium, iridium, molybdenum, tantalum, and rhenium, or an alloy containing the metal as a living body, and A thermionic emission structure characterized in that the heater tab is made of platinum.