US3003076A

US3003076A - Electron tube

Info

Publication number: US3003076A
Application number: US622694A
Authority: US
Inventors: Herman W Bonney
Original assignee: Sylvania Electric Products Inc
Current assignee: GTE Sylvania Inc
Priority date: 1956-11-16
Filing date: 1956-11-16
Publication date: 1961-10-03
Anticipated expiration: 1978-10-03

Description

ELECTRON TUBE Filed NOV. 16, 1956 FF-Z.

INVENTOR H ERMAN W. BONNEY ATTORNEY 3,003,076 ELECTRON TUBE Herman W. Bouncy, Hartsdale, N.Y., assiguor, by mesne This invention relates to electron tubes and in partic ular to the construction of the anode and its relation to other parts of the mount and to the tube envelope.

It is an object of the invention to provide for efficient cooling of the anode of an electronic tube. It is a further object of the invention to provide for effective support of the tube mount by cooperation of its anode with the interior wall of the envelope.

These and other objects will be made apparent upon consideration of the following specification when taken in conjunction with the accompanying drawing in which:

FIG. 1 is an elevation of an electron tube embodying the invention, and

FIG. 2 is a cross section through FIG. 1 on the line 2--2 thereof.

Referring to the drawing in greater detail, at there is disclosed an envelope of an electron tube which may be of ceramic such as glass or alumina or be of metal. Within the envelope and mounted on pin leads 12 extending through the stem 13 is a mount 14 which includes the electrode elements. The electron tube may be of any type. In the drawings, for purposes of illustration, there is selected a triode in which there is a cathode 16'of the filamentary type, a grid 18 surrounding the filamentary cathode and an anode structure 20 beyond the grid. In the illustrated species of the invention the filamentary cathode is shown as held under tension by a spring structure 22 somewhat similar to a mouse trap structure, the support plate 24 of which is electrically connected by a pin 26 to one of the leads 12 so as to conduct current to the bight portion of the filament trained over the spring. The grid and anode sections are held together by a pair of insulating blocks 28, such as of alumina, at the top of the mount and a second pair of insulating blocks 30 at the bottom of the mount. The grid is of a conventional form and need not be further described. The anode, however, is of novel form. The essential characteristic of the anode is that it shall have long wide wings to firmly engage the interior wall of the envelope. In the species of invention illustrated the anode is made of two electrically connected sections, each section being in the form of a channel with a web 32 of a length less than the distance between the upper and lower

insulating blocks

28, 30 and lying parallel and closely adjacent to the grid. Each of the flanges of the channel comprises a portion 34 perpendicular to the web, a second portion 36 parallel to the web and a further wing portion 38 extending away from the portion 36 and terminating in a curved portion 39 to substantially conform with and abut the interior wall of the envelope, with a large area in contact. The portion 36 of the anode is long enough to overlap the

blocks

28 and 30 and the entire assembly of electrodes and insulating blocks is held together by

rivets

40 and 41 passing through anode portions and the blocks.

Additional rivets

42 and 44, respectively, are employed to hold a connector plate 46 and the filament support plate 24 in position on the mount.

The anode structure is usually made of a metal, as nickel or nickel compound, which has some degree of States Patent resiliency. Therefore, during tube manufacture, when the envelope is slipped over the mount preparatory to sealing the envelope or bulb onto the stem 13, the wings 38 will firmly engage the interior wall of the bulb. As a result the mount is firmly held in position within the envelope not only because of the support afforded by the lead in pins 12 but also because of the extensive bearing of the wings of the anode on the inner wall of the envelope. In addition to support for the mount, the direct contact of the anode wings with the envelope afiords a free transmission of heat from the anode to the envelope thereby resulting in eificient cooling of the anode. For this purpose it will be noted, each anode section has two wings and the wings are substantially as long as the height of the anode and also extend quite a distance circumterentially of the envelope. Frequently the envelope is made of metal; in this instance it may be found to be desirable to weld or braze the wings to the envelope in order to obtain better heat transfer than can be afiorded by mere pressure of the wings against the envelope.

Having thus described the invention, what is claimed as new 1s:

1. In an electron tube, a stem, an envelope sealed to said stem, an electrode assembly mounted on said stem including pairs of upper and lower blocks supporting a grid between them, anodes secured to said blocks, each anode having a central section bent in toward the grid and lying between an upper and lower block, side portions offset from the central section and having their upper and lower portions fastened to the blocks, and wide wing portions extending toward said envelope of a length substantially equal to the length of the central section, the ends of the wing portions conforming to interior walls of the envelope and snugly engaging the same.

2. In an electron tube, a cylindrical envelope, a mount supported within the envelope, said mount comprising a unitary rigidly held together grid and anode, the anode being comprised of two metallic sections, one on each side of the grid, each section having wing portions on each side thereof extending substantially the length of the anode section and engaging the inner wall of the envelope, the ends of the wings conforming to the inner wall of the envelope and extending for a substantial distance circumferentially of the envelope and in snug contact therewith.

3. In an electron tube, a metallic cylindrical envelope, a mount supported within the envelope, said mount comprising a unitary rigidly held together grid and anode, the anode being comprised of two metallic sections, one on each side of the grid, each section having wing portions on each side thereof extending substantially the length of the anode section and engaging the inner wall of the envelope, the end of the wings conforming to the inner wall of the envelope and extending for a substantial distance circumferentially of the envelope in snug contact therewith and welded thereto.

References Cited in the file of this patent UNITED STATES PATENTS 1,304,282 Durdle May 20, 1919 1,551,391 Hennelly Aug. 25, 1925 2,129,849 Laico Sept. 13, 1938 2,171,766 Ruska Sept. 5, 1939 2,413,006 Spencer Dec. 24, 1946 2,537,225 Lewin et a1. J an. 9, 1951 2,731,579 Weiss Jan. 17, 1956 2,745,981 Sanabria et a1. May 15, 1956