Periodic permanent magnet focused travelling wave tube

Claim 2

In a travelling wave tube of the type having an envelope, an electron source for projecting an electron beam along a predetermined path in said envelope, a collector spaced from said source for intercepting and collecting the electron beam, and a helical conductor disposed within said envelope along the path of said beam for supporting and propagating an electromagnetic wave in coupled relationship to said beam for interaction therewith, the improvement including an envelope portion surrounding said helix comprising a succession of alternate high thermal conducting elongated bars having a high thermal conductivity, each of said bars including a transverse aperture, and a plurality of magnetic plates each including a transverse aperture, said bars and plates joined to one another with the apertures in alignment to form said envelope portion and a plurality of permanent magnet bars disposed between adjacent plates on each side of said longitudinal conducting bars along said envelope portion to form a succession of longitudinal magnetic fields between the apertures in said magnetic plates with the sense of the fields of adjacent magnets and plates being reversed to reverse the fields along the electron beam path, said conductive bars serving to conduct heat away from said helix along said bars and said plates serving to concentrate the field along the path of said electron beam.

Claim 3

A travelling wave tube as in claim 1 in which the aperture in said magnetic plates includes a hub extending into the apertures of the conducting bars and along the envelope.

Claim 4

A travelling wave tube as in claim 1 including heat dissipating means cooperating with the ends of said conductive bars.

Claim 5

A travelling wave tube as in claim 1 including a conductive end plate secured to each end of said conductive bars and plates to form a pocket for receiving said magnets.

Claim 6

A travelling wave tube as in claim 4 including heat dissipating means cooperating with said end plates.

Claim 7

A travelling wave tube as in claim 5 wherein said heat dissipating means cooperating with said end plates includes a plurality of air-cooled fins extending outwardly from said end plates.

Claim 8

A travelling wave tube as in claim 5 wherein said heat dissipating means cooperating with said end plates includes a plurality of tubes in intimate contact with said plates for circulating cooling fluid for removing heat from said structure.

Claim 9

A travelling wave tube as in claim 4 including a base support secured to said end plates.

Claim 10

A travelling wave tube as in claim 8 including a cover extending over said tube and heat dissipating structure and secured to said base.

Claim 11

In a travelling wave tube of the type having an envelope, an electron source for projecting an electron beam along a predetermined path in said envelope, a collector spaced from said source for intercepting and collecting the electron beam, and a helical conductor disposed within said envelope along the path of said beam for supporting and propagating an electromagnetic wave in coupled relationship to said beam for interaction therewith, the improvement including an envelope portion surrounding said helix comprising a succession of alternate high thermal conducting bars having a high thermal conductivity, each of said bars including a transverse aperture and a plurality of magnetic plates each including a transverse aperture, said bars and plates joined to one another with the apertures in alignment to form said envelope portion and a plurality of permanent magnet bars disposed between adjacent plates on each side of said bars along said envelope portion to form a succession of longitudinal magnetic fields between the apertures in said magnetic plates with the sense of the fields of adjacent magnets and plates being reversed to reverse the fields along thE electron beam path, said conductive bars serving to conduct heat away from said helix and said plates serving to concentrate the field along the path of said electron beam, and a plurality of insulating support rods spaced about the outer periphery of said helix and extending parallel to the longitudinal axis thereof, and a sleeve member surrounding said rods and in intimate contact with the envelope portion whereby to constrain linear expansion of the envelope portion and reduce distortion of the helix because of expansion of the envelope.

Claim 12

In a travelling wave tube of the type having an envelope, an electron source for projecting an electron beam along a predetermined path in said envelope, a collector spaced from said source for intercepting and collecting the electron beam, and a helical conductor disposed within said envelope along the path of said beam for supporting and propagating an electromagnetic wave in coupled relationship to said beam for interaction therewith, the improvement including an envelope portion surrounding said helix comprising a succession of alternate high thermal conducting bars having a high thermal conductivity, each of said bars including a transverse aperture and a plurality of magnetic plates each including a transverse aperture, said bars and plates joined to one another with the apertures in alignment to form said envelope portion and a plurality of permanent magnet bars disposed between adjacent plates on each side of said bars along said envelope portion to form a succession of longitudinal magnetic fields between the apertures in said magnetic plates with the sense of the fields of adjacent magnets and plates being reversed to reverse the fields along thE electron beam path, said conductive bars serving to conduct heat away from said helix and said plates serving to concentrate the field along the path of said electron beam, and a plurality of insulating support rods spaced about the outer periphery of said helix and extending parallel to the longitudinal axis thereof, and a sleeve member surrounding said rods and in intimate contact with the envelope portion whereby to constrain linear expansion of the envelope portion and reduce distortion of the helix because of expansion of the envelope.

Claim 13

A travelling wave tube as in claim 10 including heat dissipating means cooperating with the ends of said conductive bars.

Claim 14

A travelling wave tube as in claim 10 including a conductive end plate secured to each end of said conductive bars and plates to form a pocket for receiving said magnets.

Claim 15

A travelling wave tube as in claim 12 including heat dissipating means cooperating with said end plates.