JPS6035442A - Cathode frame body for electron tube - Google Patents

Abstract

PURPOSE:To perform accurate and easy connection when a filament inserted in a cathode sleeve is fixed by inserting and laser-welding the end of the filament between a pair of holding pieces arranged on top of a support member. CONSTITUTION:A cathode frame body 20 for an electron tube is formed containing a support cylindrical body 2, a conductive support member 5, a pair of cathode sleeves 7 mounted on a pair of support pieces 6, filaments 12 and 13 inserted therein, a base metal 8 provided with an oxide layer 9 and such. In this case, a plate 21 made of Invar and such is welded on top of the support member 5 and the height is adjusted properly for the cathode sleeves 7 and then the ends of the filaments 12 and 13 are loaded. Subsequently, the ends of the filaments are held between plates 22 made of Invar and such and are connected together by laser welding. As a result, connection can be performed with full strength without hindering the insertion of the filaments 12 and 13 into the cathode sleeves 7 and workability can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a cathode assembly for an electron tube, and more particularly to a cathode assembly for an electron tube in an ultrafast motion range.

[Technical background of the invention and its problems]

An example of a conventional cathode assembly for an electron tube in the ultrafast motion range will be described with reference to FIGS. 1 to 3.

The cathode assembly (1) includes, for example, a cathode support cylinder (2) formed in an oval shape, and a pair of cathode support cylinders (2) welded and fixed to the upper inner surface of circular parts on both sides of the cathode support cylinder (2). A circular cylinder (3) and a glass (4) in the center of each cylinder (3).
A pair of cylindrical conductive support members (5) are fixed through an insulator such as the above, and the oval cathode support cylinder (2
) is welded to the upper part of the inner surface of the opposite flat part of the cathode support cylinder (2) at an axially symmetrical position and protrudes upward. A pair of supporting pieces (6) are welded to each other and fixed in parallel, and the upper end of the supporting piece (6) is welded and fixed near the end so that it is perpendicular to the electron gun axis. A pair of circular cathode sleeves (7) supported by a disk-shaped base metal welded to the upper outer periphery of each cathode sleeve (7) centered on the electron gun axis (Z). (8), an oxide layer (9) for thermionic emission formed on the base metal (8), and a filament 00 formed in a coil shape, with legs (19 remaining) at both ends of the filament 00. A pair of heaters 01 are sintered and coated with alumina (6), inserted into each of the cathode sleeves (7), and have legs α) at both ends welded and fixed to the upper ends of each of the conductive support members (5). It consists of

Note that the cathode three (7) has a thickness of, for example, 1
The base metal (8) has a diameter of 5 μm, a diameter of 0.89 m, and a length of 3 mm, made of a nickel-chromium-tungsten alloy, and blackened on the inner and outer surfaces.
04-1 It has a diameter of 1.4 cm and is made of nickel.

Welding between the above-mentioned members is performed by spot welding, and the welding points are indicated by X marks in the figure to the extent possible.

Also, in this row, the cathode three f(7) and the heater α
→ Since two pieces of It is made to be perpendicular to.

Such an electron tube cathode structure (1) has a base metal (8)
is located at approximately the center of the pair of cathode sleeves (7) in the length direction of the pair of heaters, so that when a voltage is applied to each heater, The central part of each heater (I in the longitudinal direction υ each cathode sleeve (
7) The temperature rises from the center of the base metal (8) and the temperature rises extremely quickly. When installed in a cathode ray tube electron gun, the time from turning on the switch until an image is obtained is long enough when it is installed in a cathode ray tube electron gun. The image output time is about 1.7 to 2.0 seconds, and the synchronization is extremely excellent.Also, since the heater α1 is housed in the cathode sleeve (7), the heater α→ The base metal (8) and the oxide layer (9) are affected by the scattered particles of We are prepared.

However, on the other hand, there were extremely serious deficiencies as described below.

First, the filament 1 of the heater α1 is generally made of tungsten or a rhenium-tungsten alloy, and when the leg α■ is joined to the conductive support member (5), resistance welding is generally used. is used, the leg α-core is also directly heated to high temperatures and becomes brittle, which may lead to wire breakage.

Second, the wire diameter of filament αO of heater 0■ is 20~
The shape of the welding electrode is very important because it is extremely thin at approximately 30 μm. However, during mass production, the welding electrode is easily worn out, and often the welding electrode - leg part 09 - conductive support member (
5) If the contact between the legs is poor, accidents such as embrittlement and disconnection of the legs will increase due to the discharge phenomenon during welding.

Thirdly, heater α1 is coated with alumina 0 and sintered for the purpose of insulation, but due to the difference in thermal expansion coefficient between filament 10 and alumina 0 The heater 0'3 is deformed and its legs (l) are not aligned, making it difficult to position the leg θ force on the upper end surface of the conductive support member (6) and making explosive contact difficult.

[Purpose of the invention]

The present invention has been made in consideration of the above-mentioned points, and an object of the present invention is to easily and reliably connect a heater in a cathode assembly for a super-interlocked electron tube.

[Summary of the invention]

The cathode assembly for an electron tube of the present invention includes a support piece, a cylindrical cathode sleeve fixed to the support piece and supported perpendicular to the electron gun axis, and an electron gun axis on the upper outer periphery of the cathode sleeve. A base metal fixed to the center, an oxide layer formed on the base metal, a heater inserted into the cathode sleeve, and a support part disposed on both ends of the cathode sleeve at the top. and a pair of conductive support members positioned at approximately the same height as or at a lower height than the lower edges of both ends of the cathode sleeve, and the support portions of the pair of conductive support members are overlapped The leg portion of the heater is sandwiched between the support portion and the leg portion is irradiated with a laser from above so that the molten portion wraps around the leg portion and is solidified integrally with the support portion and the leg portion. It is characterized by comprising a pair of clamping pieces.

[Implementation sequence of the invention]

The cathode structure for an electron tube according to the present invention will be explained in detail based on a sample of 1 ml+ll shown in FIGS. 4 to 7.

The electron tube cathode assembly (1) of this example basically has the same structure as the conventional electron tube cathode assembly (1) described above, so the same parts are denoted by the same reference numerals. The explanation will be omitted.

In the present invention, a support part 01) is provided on the upper part of a pair of conductive support members (5) arranged at both ends of the cathode sleeve (7), and each support part Q is connected to the cathode sleeve (7). It is set at approximately the same height as the lower edge of both ends or a height lower than that, and each support part 01) and each clamp piece) are superimposed on each support part 01) and each clamp piece). The leg 0υ of the heater 01 is clamped between and the laser is irradiated from above each clamping piece (c) to the center of the leg θ hidden in the clamping piece (a).
The two legs α and the support portion (C) are brought into explosive contact with the clamping piece so that the molten part of the clamping piece (A) wraps around the leg α■.

In this case, the pair of support parts (c) may have a thickness of 0, for example.
2 trm, width 0.55 ttcm, length 1.5~
A plate made of invar or copal of about 2 tm is formed separately from the conductive support member (5), and each support part Q]) is formed separately from the conductive support member (5) before inserting the heater (B) into the cathode sleeve (7). It is spot welded to the upper end surface of each conductive support member (5). In addition, the pair of clamping pieces) have a thickness of 0.2mm and a width of 0.551111mm, similar to the above-mentioned support part (c).
+, Use a board made of Invar or Kovar, etc., about 1.5 to 2 inches long.

Next, the structure of this electron tube cathode structure will be explained.

First, each cylinder (3) is positioned so as to be in contact with the upper inner surface of the circular portion on both sides of the cathode support cylinder (2), and fixed by resistance welding, Rede welding, or the like.

It is assumed that a conductive support member (5) is inserted into each cylinder (3) in advance and fixed in an insulating state by adhesive or f-sis (4).

Next, a position close to a different cylinder (3) on the inner surface of the opposing flat part of the cathode support cylinder (2), that is, an upper part of an axially symmetrical position on the inner surface of the opposite flat part of the electrode support cylinder (2). Each support piece (6) is fixed by resistance welding or Rede welding.

Separately, a pair of cathode sleeves f (7) are welded in parallel so as to touch each other, and treated at high temperature in a hydrogen furnace with added moisture to form a blackened coating on the inner and outer surfaces of the cathode sleeve (7). form. In addition, on the contrary, a single cathode sleeve (7)
After blackening treatment, the two cathode sleeves (7)
It is also possible to weld.

Next, the substrate gold R (8) on which the oxide layer (9) is deposited L7 is placed on the center of the pair of cathode sleeves (7) and welded using a laser or the like.

Then, a pair of support pieces (
6) Attach to the upper end using laser explosion welding, etc.

Next, the support portion Q]) is fixed to the upper end surfaces of the pair of conductive support members (5) by resistance welding, laser explosion welding, or the like.

Next, a pair of heaters a1 is inserted into the center of each cathode sleeve (7). At this time, since the supporting portion Q of each conductive supporting member (5) and the lower edge portions at both ends of the cathode sleeve f (7) and the hill # are located at the same height or at a lower height, the heater 01 (support part QI)
Since the thickness of the heater (II) can be made sufficiently large, the leg θ of the heater (II) will always be located above the support portion 01 even if the leg 0] of the heater α] is deformed.

Then, each clamping piece) is superimposed on each supporting part 01), and the leg part αυ of the heater 01 is clamped between them.

Next, at the position where the zero center of the leg of each clamping piece υ and each heater α1 changes, from the side of each clamping piece (B), from the top of each clamping piece (to each clamping piece), to each clamping piece (C). A pulse oscillation radar is irradiated with a target on the hidden center of each leg a, and as shown in FIG. The support portion 01) of 5) is integrally welded and fixed to complete the electron tube cathode assembly (a).

In this case, the melting point of the clamping piece (A) and the support part 0 is sufficiently lower than that of the filament (Off) of the heater 0e, so the leg part 0
The heart does not melt or become brittle due to crystal growth.
The force of the leg part α is wrapped in the fused part (b) of the clamping piece melted by Rede, and further, the fused part (c) of and is melted and integrated with the supporting part H.

In addition, in the above-mentioned actual m row, the supporting part (c) and the clamping piece (a) were formed in advance to a predetermined size and assembled together, but the present invention is not limited to this, and it is possible to supply the support part (c) and the clamping piece (a) in a band shape, After welding it to a predetermined position, it may be cut to a predetermined size. In addition, the support part may be formed separately from the conductive support member (5). For example, the support part may be formed separately from the conductive support member (5). It is also possible to form an integral body with a shape like this.

Further, in the embodiments described above, the cathode sleeve (7) has a circular shape, but it is not limited to a square shape, and other shapes such as an oval shape or an elliptical shape can be similarly applied. ) also supports not only the outer side of the pair of cathode sleeves (7), but also the inner side of the pair of cathode sleeves (7), or the lower side of the cathode sleeves (7). However, the pair of cathode sleeves (7) are not limited to those that are directly integrated with each other by welding, but may be integrated indirectly with separate connecting pieces, etc. , it can be applied even when there is only one cathode sleeve.

〔Effect of the invention〕

As described above, according to the present invention, the support part provided on the upper part of the conductive support member is located at approximately the same height as or at a lower height than the lower edges of both ends of the cathode sleeve. The heater can be inserted into the holder without any hindrance, and since the support part is provided on the top of the conductive support member, even if the heater is deformed during manufacturing or handling, the legs of the heater will remain intact. The heater legs are always located above the support part, and there is no need to do any special positioning of the heater legs.Since the clamping pieces are overlapped on the support part and the heater legs are clamped, it is necessary to securely hold these three parts. Since the welding is performed by laser welding and the laser beam is irradiated from above the clamping piece, the legs of the heater are not directly heated.
Therefore, it is possible to maintain sufficient strength and provide a product with excellent reliability and durability, as well as reduce the yield rate of the heater legs, which have become brittle and prone to breakage. Since the material has good strength, it can be manufactured at low cost.

[Brief explanation of the drawing]

1 to 3 show a conventional cathode structure for an electron tube, in which FIG. 1 is a perspective view thereof, FIG. 2 is a plan view thereof, and FIG. 7 to 7 show the cathode structure for an electron tube according to the present invention, FIG. 4 is a perspective view thereof, FIG. 5 is a plan view thereof, and FIG. 6 is M and M in FIG.
The cross-sectional view and FIG. 7 are enlarged views of the main parts. (5) Conductive support member, (6) Support piece, (7)
・Cathode sleeve, (8)...Base metal, (9)...Oxide layer, 0th...Leg, (11...Heater, (1)...Cathode structure for electron tube, (C)...Support part, ni)...pinching piece,
(Z)...electron gun axis.

Claims (1)

[Claims] (1) A support piece, a cylindrical cathode sleeve fixed to the support piece and supported perpendicular to the electron gun axis, and fixed to the upper outer periphery of the cathode sleeve so as to be centered around the electron gun axis. a base metal formed on the base metal, an oxide layer formed on the base metal, a heater inserted in the cathode sleeve, and support parts disposed on both ends of the cathode sleeve at the top, the support parts being A pair of conductive support members located at approximately the same height as or at a lower height than the lower edges of both ends of the cathode sleeve, and a pair of conductive support members that are overlapped with the support portions of the pair of conductive support members and are connected to the support portions. A cathode assembly for an electron tube, comprising: a pair of clamping pieces which clamp the legs of the heater and which are irradiated with a laser from above and are integrally fixed to the support part and the legs. .