close

Вход

Забыли?

вход по аккаунту

?

Патент USA US2403795

код для вставки
July 9_, 1946.
2,403,795
w. c. HAHN_
HIGH ‘FREQUENCY APPARATUS
Filed April 26, 1941
3 Sheets-Sheet 1
20a
37
22
. Inventor:
vWilliam _C. Hahn,
His Attorney. J
July 9,1946.
_
'
_,
w. c. HAHN
~
2,403,795
arm: FREQUENCY APPARATUS
Filed April 26, 1941
3 Sheets-Sheet 2
Inventor:
William C. Hahn,
b x1
am
y Hiasltzttofneg.
July 9,1946.
»
w.~c. HAHN
- ._
HIGH FREQUENCY APPARATUS
Filed April 26, 1941
2,403,795
5 Sheets-Sheet 3
fig. /0.
Inventor;
WiHiam C. Hahn,
by z/wmw
Hisv Attovn'eg.
Patented July .9, 17946
* 2,403,795
.UNITED STATES PATENTVOFFICE‘
HIGH-FREQUENCY APPARATUS
William C. Hahn, Scotia, N. Y., assignor to Gen-.
> eral Electric Company, a corporation of New
York 1
Application April 26, 1941, SerialNo. 390,527
11 Claims.
(01. 315-6) '
1
.
2
,
~
if a uniform stream of charged particles is caused
to traverse a region which is subjected to cycli
locity modulation and is considered useful in con
nection with high frequency oscillators, ampli
?ers, detectors, etc.
,.
‘In the aforesaid patent it is pointed out that
The present invention relates to ultra high fre
quency apparatus utilizing the principles of ve
cally variable potential gradients, the various ele
merits of the stream will be differently a?ected
'
It is a primary object of the invention to pro
. as to velocity. That is to say, if the particles are
'vide ultra high frequency apparatus which is
capable of realizing high power output and which
is characterized by a high degree of stability and
~
reliability in operation. In this connection an 10
electrons',those electrons which traverse the given
region when’ the gradient in it is positive will be
accelerated, while electrons which enter. the re;
gion during periods of negative gradient will be
important feature of the invention consists in an
arrangement in which a stream of charged par
deceleratedr ‘In the event that the potential ap
number of intercommunicating and mutually
this condition corresponding to so-called (‘velocity
coupled sections each of which is individually res
modulation’_’ ofthestream.
plied to'tlie said regionv is of cyclically reversible
ticles (e. g. electrons) is caused to traverse an
character, :thepo'rtion ofwthe electron stream is
elongated chamber which is of continuously con
suing from the "region will be' characterizedby
ductive character and which is subdivided into a 15 alternate components, of high and low velocity,
onant at a common frequency. It is shown here
_
V
g
‘
rBriefconsideration will show that‘if a velocity
in that by properly correlating the velocity of
modulatedrelectron stream is permitted to con- "
the charged particles tothe longitudinal dimen 20 tinue?alonga ?xed path, a regrouping of the elec
sions of the various chamber sections, useful high
trons’ will?occur 3S a result of the tendency of
frequency energy conversion effects may be ob
thegfasterelectrons to catch upv with the slower
tained by the mutual reaction of the charged
ones. Consequently, after an appreciable inter
particles and the structural elements of the cham
val of time,the stream will assume a “charge
ber. For example, in accordance with one mode 25 density modulated” character ‘in the sense that it
of use of the invention, the charged particles may
will possess anunequal space distribution of elec
be made to maintain the chamber in a condition
of continuous resonant excitation such that it
trons.
may be used as a ?xed frequency oscillator for
the generation of high frequency waves,
Thefeatures of the invention desired to be pro
.
.
' ‘The present invention makes use of the phe
nomena describedabove in that it employs the ex
30
pedient of successively producing velocity modu
lation. of anelectron stream and thereafter con
. tected herein are pointed out with particularity
verting the velocity modulation into chargeden
in the appended claims. The invention itself, to
sity modulation for the accomplishment of cer
gether with further objects and advantages there
tain desired results. ,
.
'
.
.
of, may best be understood by reference to the 35 , Referring particularly to Fig. 1, there is shown
following description taken in connection with
an exemplary embodiment of the invention in the
thedrawings, in which Fig. 1 is a longitudinal
form of an elongated evacuated discharge tube
sectional view of a discharge apparatus suitably
terminating at one end in a bulbous glass por
embodying the invention; Fig. 2is a cross sec‘
tion in. The part II) includes a reentrant stem
tion taken on line 2—-2 of Fig. 1; Fig. 3 represents 40 H which terminates in a press [2 for supporting a‘
a single section of the discharge chamber of Fig.
V ?lamentary cathode I4 and a pair of aligned con
1, modi?ed in a manner which assists in explain
ductivelmetallic) ‘cylinders l6 and H. The for
ing the operation of the invention; Fig. 4 is a
mer of the two cylinders serves primarily to con
diagrammatic view representing the circuit ana
logue of the structure of Fig. 3;v Fig, 5 is a frag 45 ?ne the, electrons released from the cathode [4
to 'aiconcentrated‘beam and to this end may be
mentary view also useful in explaining the in
either connected directly to the cathode as shown
vention; Fig. 6 is a longitudinal section of a mod
or maintained a few volts negative or positive
i?ed embodiment of the invention;*~Fig. 7 is a
with respect to it. The cylinder ll acts to accel
cross section taken on line 1-1 of Fig. 6; Fig. 8
shows a further modi?cation; Fig. 9 is a cross sec 50 erate the electron stream and is accordingly bi
asled to'a'f suitable positivepotential, say several
tion taken on line 9—9 of Fig. 8; Fig. 10 illustrates
hundreduvolts, with respect to the cathode,
astill furtherrmodi?cation; Figs. 11 and 12 joint
' In" addition to the bulbous part It), the tube
envelope includes an elongated‘ hollow conductive
structurewhichis designated as a whole by the
numeral 20 and which is joined to the part In
1y illustrate a still further modi?cation; andrFig.
l3shows the application of the invention to an
ampli?er.
v
.
_ Before proceeding to a detailed description of
the invention it will be helpful to consider brie?y
some of the principles vof velocity modulation as
the same are set forth, for example, in my prior
Patent2,220,839, granted November 5, 194D.~ f 5.0
s
by means of a hermetic seal indicated at 2| A
coni‘cally shaped metallic member 22 covers the
seal. between the glass and metal parts of the
tube andserves to Shield it from the e?ept of the
2,403,795
3
4
high potentials which may be developed within
tions, become charge density modulated as the
faster electrons overtake and become grouped
with the slower electrons.
Under proper circumstances, the charge groups
thus produced in the stream may be expected to
the tube during its use.
The tube part 20 is of continuously conductive
character, being preferably constituted of an as
sembly of copper or brass rings, and is charac
terized internally by a series of recurrent discon
tinuities. In the particular embodiment shown
in Fig, 1 these discontinuities comprise a number
of perimetrically complete (e. g. annular) wall
release energy to the resonant structure in such
fashion as to maintain it in continuous oscilla
tion. In my prior Patent 2,222,902, it has been
Shown in connection with a system which, from
parts 25 to 2‘! which e?ectively subdivide the 10 this standpoint, is analogous to that here being
main body of the tube into a series of identical
sections.
These wall parts de?ne between them
a succession of gaps 3D to 33 which are succes
sively traversed by the stream of charged parti
cles projected from the cathode 14. After trav
ersing the gaps, the stream is collected by'a me
tallic end wall 35 which closes the extremity of
the tube.
In the operation of the tube, the structure 20
may be maintained at ground potential and the
cathode at one to several thousand volts below
ground. This may be accomplished by the use
of a D. C. voltage source which is illustrated con
ventionally as a battery 36 and which also serves
to bias the electrode I‘! to the desired potential.
The electron stream developed by the coaction
of the various tube elements may, if desired, be
maintained in focused condition by the provision
of a direct current excited magnetic focusing
coil 31.
30
In order to understand the practical operation
considered that the maintenance of sustained 0s
cillations requires that the average electron
transit time between successive gaps shall depart
somewhat from the value previously assumed
herein, that is, from equivalence to an integral
number ‘of complete potential cycles at the op
erating frequency. The preferred amount of
such departure is a function. of the number of
gaps employed in the system as a whole, and is
indicated in the following table, in which 0b rep
resents the part of a cycle (one complete cycle
being equal to 360 degrees) which is required for
the transit of an electron from a given point in
one gap to a corresponding point in the next suc
ceeding gap.
Table
Number of gaps
0b
Degrees
2
of a structure of the character outlined in the
foregoing, it should be noted that the part 20 may
be viewed in two aspects. In the ?rst it com
prises a series of electrode elements for influenc
ing the electron stream traversing it. In the sec
ond it may be considered as a unitary resonant
system adapted to be maintained in continuous
oscillation by the reaction of the electron stream.
The relative dimensions of the various parts of
the structure should be such as to permit it to
The significance of the foregoing table may be
summarized by saying that most effective mutual
reaction of the electron stream with the resonant
structure 20 will occur when the longitudinal di
mensions of the various structural parts are so
function satisfactorily in both of these capacities.
correlated to the stream velocity and to the de
In order further to clarify the matters just re
sired operating frequency as to bring about a
ferred to, it will ?rst be assumed (subject to later
value of 6s corresponding to the values indicated
justi?'cati'on) that the structure 2'0 may be main 45 in the table. It should be noted in this connec
tained in a vcondition of sustained oscillation
tion that no change in operation will-occur if for
(resonance) ‘such that cyclically reversible poten
any selected number of gaps the value of ‘9b given
tial gradients appear across the gaps 30 to '33
in the table is increased by 360° or by some in
inclusive. It is assumed further that the circum
tegral multiple of that angle. Thus, if a six-gap
stances of operation are such as to cause the gra 50 system is to be used and design considerations
dients existing in the‘ various gaps tobe of similar
make it desirable to employ an electrode length
magnitude and to have a common direction at
greater than that which would correspond to
any given time. (It will be pointed out‘ at a later
335°, equivalent results may be obtained by using
point that this represents only one of several
335° plus 360°,or 695°. It will be understood
equally possible modes of operation.) Under
from a consideration of the table that in every
these circumstances it is clear that the electron
case the average electron transit time from gap
stream traversing the various gaps necessarily
to gap will be on the order of the time con
undergoes some degree ‘of velocity modulation.
sumed by an integral number of complete cycles
Moreover, such modulation is most pronounced
of potential variation (at the desired operating
if the electron transit time between corresponding
points in two adjacent gaps corresponds at least 60 frequency of the apparatus), but will depart
therefrom by a fraction of a quarter-cycle of
approximately to an integral number of complete
such variation.
cycles of potential variation at the operating fre
The operation of the apparatus as so far de
quency of the apparatus.
scribed may be summarized by saying that the
With the above speci?ed conditions ful?lled, it
is apparent that electrons which reach the ?rst 65 electron stream projected from the cathode I4
is modulated as it traverses the initial gaps in
‘gap 39 in such time phase as to be accelerated
the resonant structure; that this modulation is
by the potential gradients existing across the gap
effectively ampli?ed by the occurrence of elec
will be still further accelerated as they traverse
tron-grouping effects as the stream progresses
the Various subsequent gaps. Conversely, elec—
trons which are decelerated at the ?rst gap will 70 longitudinally of the structure, and that a por
tion of the energy of the modulated stream is re
be repeatedly decelerated at the remaining gaps.
leased to the resonant structure at the various
The net result’ will be that as the electron stream
gaps subsequent to the ?rst gap to maintain the
passes longitudinally through the structure 20 it
structure in continuous oscillation. On this lat
will develop signi?cant velocity differences from
point to point and will, in itsmore advanced por to ter point it is assumed that su?icient mutual
2,4o3,79c.
V
V
5
space coupling exists between the varioussec
terminally short circuited by the wall part 20a,
tions of the resonant chamber to assure that the
forced, oscillation of the sections last traversed
by’ the. electron stream shall be communicated to
the sections ?rst traversed by the stream so as
\ and the two lines‘ are joined by the axially ex
tendingsurfaces 26a and 21a. It may be assumed
that from an approximate viewpoint, resonance '
will occur when, the impedance looking into the
to maintainthese also in an oscillatory condi- ‘
?rst mentioned transmission line (the line A)
tion. It is found that such coupling exists to a
from its inner periphery is equal and opposite
satisfactory degree provided the various chamber
to the impedance of the second named transmis~
sionv line as viewed from the region of its junctionv
sections are in communication withsone another .
through openings having a diameter which is not 10 with the ?rst line. In another manner of state
less than their. axial extent. This -. condition. is
ment, this means that the effective inductance of
obviously ful?lled in the arrangement illustrated ' transmissionv line A must resonate with the e?eca
tive capacitance of transmission line B; the,
in Fig. '1 in which the ratioof the diameterof
lumped circuit analogy of this situation being"
the openings in the wall parts 25 to 21 tothe.
represented in Fig. 4. In the latter ?gure, the
15
length
Assuming
of such
favorable
openings circumstances
is on the orderof
,(including
.2: 1.
various circuit elements are numbered to cor
respond insofar as possible to the equivalent struc
an electron stream of adequate intensity), a suf
?cient, amount of energy may be released from s
tural elements of Fig. 3. The resulting combi
the electron'stream tothe resonant structure 20
nation includes inductive components 26' and.
so as not only to supply the losses of the struc
21' which are balanced (at resonance) against a
ture and to maintain the same in excited condi
capacitive ‘component B’.
a
-
tion, but also to permit abstraction of a portion
Considerations of symmetry indicate that a
of the energyfor external utilization. Such ab
large number of identical resonant chambersv of.
stractionmay be accomplished-in one way, for
the character shown in Fig. 3 may be placed»
example, by the provision of an inductive. loop 25: end-to-end and‘ the partitions between them re
3'!’ which is coupled into the spaceenclosed by
moved without modifying the conditions of'resé
the structure 20 and which connects externally
with an appropriate utilization device such as a
onance of the various “units.
conducting medium, is electrically resonant at
wholly unidirectional at any given instant,.?ow
and con?guration of the space.
toward either ‘one ‘end orthe other end of
the‘ ‘chamber. ‘For either case a compensatory
(This, of course,
produces the construction of Fig. 1.) For the
short-wave antenna 38.. With this arrangement
end section 30 there is some dissymmetry due to
the apparatus as. a whole is obviouslyadapted for 30" the necessity of providing in abutment with this
section an open-ended tube 42 through which. the
use as an oscillator for the generation and prop
agation of high frequency signals.
' -' . ‘ .
r
electron beam may enter the resonant chamber.
(This .tube should have a diameter less than
In order still further tov explain’ the matters
about .6 times the operating wave length and a
referred-to in the foregoing, it will be helpful to
examine briefly the factors. which control the 35 length at leastseveral times its diameter in‘
order to avoid radiation through it of highfre
resonant. operation of a system suchv as‘ that
quency energy generated within the chamber 20.) .
formed‘ by the structure .20. This ‘may be‘ done
The effect of this dissymmetry may be compens
most ‘easily by reference to Fig. 3 which illusated, however, by an end correction in the form
tratesby Way of example the third section of the
of a reentrant annular vcollar 43 the function of
structure 20 and whichshows the’extremities of
which is to add effective inductance in the end
this section. as ‘being closed by "conductive par
chamber to correct for the reduced capacitance.
titions 40 and 4| extendingv through the central
attributable to the presence of the tube 42.
planes of the‘ wall parts 26 and 21.v
‘ I
‘
During operation of a structure of the type
FAs thus modi?ed, the section in question com
under consideration, the ?ow of conduction cur
prises a closed chamber including a cylindrical
space‘B which is surrounded vbylandxmerges-‘(at . rent will obviously be con?ned wholly- to'the walls
» of 'the "resonant chamber. Moreover, for . the
the boundary X) into an annular space A. This
chamber, like any con?ned space bounded by'a ‘ most probable condition of operation, it will be
various'frequencies determined'by the dimensions-v a1 ing
"
r .
1
>
..
displacement current, ?owing in the opposite di
rection, exists near the axial region of the cham
- In order to analyze the properties of the cham
ber of Fig. 3 in» a useful Way, one may set up Max;
well’s- ?eld equations for 'theenclosed space and
solve the equations in a manner ‘consistent with
is "From another point of view the structure of
the speci?ed boundary conditions. In-an article
Fig. 1 may be regarded as a modi?ed form ofv
ber.
'
.
’
-
.
"
resonant waver guide,_analogous to'the wave-guid
published in- the Journal of Applied Physics-for
ing systems described by G. C. Southworth at
January 1941 at pages62 to 68 I have shown'one
, pages 284 to 308 of the Bell System Technical
procedure by which such an analysis maybe car
ried out. This analysis includes ‘the derivation 60'? Journal for April 1936. 'In the publication‘ire
or equations which permit the resonant frequen;
cies'» of a chamber of the type in question to be .
ferred to it is pointed out that a continuous con
, ductive tube ?lled with a dielectric medium may
determined if its dimensions are known,'and
be used for» the guided propagation of. high
which further allow a missing dimension to be
frequency electromagnetic waves " in spite ‘of
calculated if the‘ remaining dimensions and- the" a the‘ apparent absence of a conductive return cir-,
cult of the character usually regarded as nec~f
desired operating frequency are taken as ?xed. 1'
essaryvto any channelized ?ow of electrical en
The form of thesolution 'given'in the article
ergy. The waves which may be propagated in
mentioned above suggests that a structure of the
type/under consideration may be ‘conveniently this way include, among others, ‘waves having‘
electric force components which are-‘con?ned to
viewed as- comprising: the combination or'two?
radial “transmission lines” (corresponding to the
the axial and radial directions and ;magnetic
spaces A and YB), the former comprising'l‘the'f op—'
force components which are wholly ‘azimuthal;
posedannular surfaces of the parts‘ >26‘and 21'
such waves‘being arbitrarily designated as -E’o~
and 'the‘ latter‘ being made-up ‘or ‘the 'disk-like-j
partitions 'llll’a'nd' 4|. The first line’is obviously‘
_ waves. ; Under . appropriate circumstances!
waves of de?niteifrequencyifmay be ‘caused to
2,403,179.54
7
8
exist in/a standing wavepattern within a wave
ation
the scope-or thepresent-invention
guide of ‘given dimensions,~ this condition. being
provided the electron transit time between suc
taken to de?ne resonance of the waveguide for
the ‘particular 1 frequency involved.
The. application to the present invention of the
cessive' gaps is made to correspond approximately
to an-oddnumbe'r (including unity) of'h'al'f-cycles
of'p‘otential variation so that cumulative acceler
matters stated in the foregoing may Joe under
ation» and- deceleration effects are realized at the
various gaps;
stood by reference to Fig. 5, in which the solid
In the-design- of a resonant system of the type
line structure 45 represents a tubular wave guide
under consideration (e. g. in Fig. 1) it is gener_
of- dimensions chosen to provide a particular res
10 ally expedient'to assume ap'rac-ti'cal dimension for
onant frequency for E0 waves.‘
the interior diameter of parts 2-5, 26, etc; next,
.JLet it now. be assumed that the diameter of
to select a convenient operating voltage; and
the'ltube is vdiminished at periodically spaced
from this and the desired frequency to compute
regions. 46 to .43, for examplaby inward de
the longitudinal dimensions of the system. This
formation of the tube wall. Due to the relation
ship .oflthe magnetic and electric force compo 1.5 leaves still undetermine'd'the diameter of the
chamber in the regions between the parts 25 to
nents in E0 waves, asde?ned above, the volume
21., but this may be calculated by the ‘procedure
a?ectedrby the proposed change is that in which
given in the Journal of Applied Physics vfor Jan
magnetic energy storage is predominant. Con
uary 1941 to which reference has already been
sequentl'y, the change reduces the inductance of
'
the system without correspondingly varying its 20 made.
With the dimensions of thestructure thus de
capacitance and thus tends .to raise the resonant
frequency of the structure of .a Whole. In order
termined, one may next compute the losses of
the system (mainly resistance losses in the wall
to onset this effect and to provide enough added
parts of the structure.) and decide upon a beam
inductance to restore the original condition of
resonance, the diameter of the remaining p01‘ 25. current sufficient to provide-for these losses and
to permit useful-power to be‘ taken from the sys
tions of the tube may be increased as indicated
tem. Provided the chosen conditions of opera
at 49', 56, 5!, and 52 so as to provide added
tion prove to bersuch‘ vas to assure the operation
volume .for magnetic energy storage; With'this
of the system- in its desired mode of resonance
change the wave guide ought to function essen
tially as it did inits original condition in so far 30 to ‘the exclusion :of other ‘and unwanted modes,
the design “may .be accepted as a practical one.
asresonant operation is concerned.
One advantage of electronic apparatus of the
, It will be realized, however, that due to ‘the
type herein described’ lies ‘in the fact that all
existence ofv the gaps 54 to 56 a structure hav
parts of theresonant structure are directly elec
ing the con?guration indicated by the dotted line
will be characterized, when in resonance, by the 35 trically connected and may therefore be main
tained at a ?xed D. C. potential. This means
existence of periodically spaced and sharply
de?ned variations in the axial potential gradient,
thatv the operation of the apparatus will be free
from sporadic variations due to wall-charging
which variations are not present in the smooth
or the like, irrespective of the number of cas
tube 45. In the use of the structure in a system
in which an electron stream axially‘ traverses the 40 caded' sections which are included.
structure, these variations may be made to pro
duce a signi?cant reaction on the electron stream,
and under .proper conditions to result in the oc
An alternative type of oscillator, shown in
Fig. 6,‘ comprises a. bulbous glass envelope portion
60 which is joined vat its open end to an elongated
metal tube 6|. Areentrant stem 62 provided in
currence of self-sustained oscillations. From'this
viewpoint then, the dotted line structure of Fig. 45 connection with the glass part 60 supports the
combination ‘of a'cathode 63, a focusing electrode
5, although derived and described on the basis
64 and ‘an accelerating electrode 65, these ele
of waveguide principles, isthe functional equiv
ments being adapted to project a stream» of elec
alent of the chamber 20 of Fig. 1.,
..
trons axially of the envelope. Focusing and en
- It .may also be noted at this point that any
resonant system of the type under consideration. 50 ergizing means similar to those shown in Fig, -1
may be employed.
is characterized by a theoretically in?nite num
ber of modes of resonance. It is, of course, ine
tended that in practical use, a given apparatus
shall be restricted to a single preselected mode
, The‘metal tube I is closed ‘at its extremity
by :a transverse metal, wall 66 which serves to
collect the electrons after their traversal of the
of resonance by judicious choice of the operating 55 tube. The tube further surrounds and supports
a series of, metallic partition-forming elements
conditions, including appropriate selection of the
which, subdivide‘ the enclosed space in a manner
operating voltage and beamv current. On the
analogous-to the parts 25 to 21 of Fig. 1. In this
other hand, some structures may well have a
case, however, the partition-forming elements
number of modes ofv operation, all of which-are
comprise a series of abutting rings 68 to ‘H of
realizable by the use of practically attainable
relatively large diameter having smaller coaxial
operating conditions. It is, therefore, in no sense
tubular elements 13 to 16 joined thereto by thin
a departure from my invention to so modify the,
imperforate annular webs 18 to 8|. A passage
operating conditions of a given apparatus having
for electrons into the sectionalized chamber de
a construction of the type disclosed herein asto
procure its operation in a ‘mode of ‘resonance dif 6.5.. ?ned by thev elements-just referred to is provided
through" a tubular member 82 which connects
ferent from that speci?cally assumed in the fore
with-the?rst-sectionof the chamber.
going. For example, a resonant structure such
A system such as that shown in Fig. 6 may be
as, that shown in Fig, 1 and having an even
made to-operate in much the same manner as
number of gaps may be expected to resonate not
the-apparatus» of Fig. 1. That'isto say, assuming
only under such circumstances that the potential
proper correlation of the electron velocity with
gradients inthe various gaps are at any~given
the spacing of the rings and with the desired
time unidirectional (as above explained), but
operating frequency, e?ective mutual reaction of
alsoin ,anyalternative condition such that the
the-'velectron stream-and the structure traversed
gradients in alternate gaps are oppositely direct
ed. flfh-ishrepresents a useful condition of opera
by-it- may befexpectedito occur at the gaps be
9
16
tween the rings 13-16 in .such a manner as to
shown in Fig. 9-which serve to prevent undesired
produce concurrent modulation of the former and
excitation of the latter. The oscillations thus
established in the space within the tube BI may
be caused to produce useful external e?'ects'by
means of a coupling loop 85 .which'connects with
. propagation of wave energy outwardly through
, the space during operation of the apparatus.)
The remainder of the cylinders serve partially to
5
coaxial conductors 86, and 81 extending out
wardly through the wall 66. .
'
J
a ‘f
subdivide the interior of the chamber in a man
ner analogous to the partitions 2‘5—2'l of Fig. 1.
By virtue of this subdivision each of the sec
tions of the chamber may be ‘considered ‘as a sepa
l ‘.
rate resonant compartment having, as in the case
It is found upon analysis that an annular space
such as thatbounded'by the?yopposed webs ‘I8 10 of the‘ structures previously described, a reso
nant frequency determined by the dimensions of
and ‘I9 and the various conductive surfaces which
its, component parts.‘ When the structure is in a
are continuous therewith. presents a greaterfap+
condition of resonant excitation, cyclically re
parent, inductance at its inner,‘ boundary than
does a chamber such as the space‘ A of Fig-3+ _ versible potential gradients directed axially ofthe
assuming like radial dimensions and spacing of v15 chamber may be expected to exist at the gaps
which separate the vvarious cylinders. ‘Conse
partition centers. On the other hand, the'ap
quently, as the electron streamfp‘asses in proxim
parent capacitance. observed at the same bound
ary—looking toward the centralaxis of the chain-‘
ity to these gaps, its constituent electronswill be
variously accelerated and decelerated in ‘such a
ber—,is identical. for the two structuresmsince
~ theinductance of the outer space is variable with 20 manner as to produce'velocity modulation of the
the rlradialpdimensions of the partitioning ele
stream; > If' the resonant structurewere excited
ments,.v thisjmeans that for a, given diameter of
from an external‘ source, most eifective modula
tion' could be produced by making the‘ electron
‘ central, opening, theover-all diameter of vthe
chamber- required for resonance is less in the Fig. , transit time‘between corresponding points in ad
6 construction than in that of Fig. 1. This per 25 jacent gaps equal‘to an integral number of com
tion to be made in a- relatively ‘more'comp'act
plete cycles of potential variation at the resonant
frequency (or, for certain modes of operation,
form”
to an integral number of half cycles atsuch ‘fre
mitsiapparatus embodying the former construc
,
M
,.
>
,,.
-
quency). However,‘ in order to assure the‘ main;
losses of resonant structures of the type under 30‘ tenance of sustained oscillations with the self-7ex
cited arrangement shown, the spacing‘ between
consideration are. also mainly a function ‘of the
adjacent gaps should ‘be slightly less than that
dimensions of the radially extending ‘parts. ' ,Con
,
Calculation ,further ‘shows. that the internal
sequently, in situationsrin‘ whichit is important
to keep such losses‘ ata low/value, it
advan-. .
‘tageous'to employ the construction of Fig’; v6.
The optimum design in this connection is believed
to. be that in which‘ the__wa1l ;par»t‘s.13-f‘-8l..are
made'as thin as is reasonably possible-fsince this
35
‘be abstracted for external use by means ofv an
appropriate coupling loopjl05. In this instance
permits the radial dimensions‘of these parts re
quired for resonance to be made a minimum. , _
calculated to'give'the‘result just speci?ed._ With
this ‘condition ful?lled, a‘portion of the oscilla;
tory energy developed Within the chamber 90 may
40
v‘ In some instances the ‘subdivision of the reso
nant chamber may advantageously be accom
plished by other means than inwardly extending
the'loop I05 connects with an antenna I06 which‘
is wholly within the‘vacuum space, being‘ ter
minally con?ned by a glass closurev member 101.
‘Fig. ilO‘iIIustrate‘sa construction which com
bines certainof the features of Figs. 1 and 8, In
this case, the resonant system ‘comprises‘an elon
gated cylindrical “chamber H0 having ‘an axially
partitions such as are illustrated in Figs_.'1,-'7.
extendingconductive shaft I vI I whichcbea‘rs afse- V
'ries of conductive‘ cylinde‘rsjl I 3-H 6 inclusive.
One such alternative embodiment is shown in
Fig. 8, which illustrates only the resonant struc
ture, the remaining components of the discharge
tube being omitted in the interest of simplicity;
' Each of the cylinders is surrounded by an annular
‘conductive partition I20’-I23 which still-‘further
increases the degree of subdivisionof the cham—
In this case the chamber within which oscilla
tions are to be developed is in the form of an 50 ber. ' ‘However, the annular passages‘between ‘the
outer'surfaces of the members‘ I] 5-416 and‘ the
elongated conductive cylinder 90 which at one end
inner surfaces‘ of ‘they members I20‘--'I'23 permit
is joined through a smaller cylinder 9! to a glass
an electron stream to be projected longitudinally
envelope, of which only a fragmentary portion
of the‘ chamber. In the‘ caseillustrated, the ‘elec
92 is illustrated. ‘It is assumed that the enve
tron stream'comprises a single pencil of electrons
lope 92 contains means. (not showmffor project
E which’is injected into the chamber through'a
ing an annular streamrof electrons longitudinally
tubular opening I28 and'which leaves the cham
‘ of‘ the chamber 90‘ as indicated by the arrows D.
her at its opposite extremity through an aligned
_'(The electron source employed in this connection
may comprise, for example, an arrangement of
the type'described in application ‘Serial No.‘ 347,
opening I29, being. intercepted upon its issuance
60
from the chamber by a ‘collecting electrode I30.
744 of Louis Tonks, ?led July 26, 1940, Patent
The electrode-3H0 is insulatingly supportedwith
No.) 2,276,806, dated March 17,1942 and assigned
'to th'e‘same assignee as the present application.)
Arranged coaxially within the chamber 90 there
is provided an elongated conductive shaft 95 hav
ing mounted ‘thereon a series of equally ‘spaced
respect to the chamber from an insulating (e; g.
glass) wall'l3l and isassumed to'be maintained
at’ a potential adapted to assure the collection
of ‘all‘th'e electrons.
,
,
Obviously the generalv considerations which
conductive cylinders~ 91—‘l02, the cylinders being
have previously-been stated herein as governing _
mounted on and electrically connected to the
shaft by means of imperforate diaphragms as'in
dicated at I03. The cylinder 9-1 occupies a sub
th‘e resonant operation of'subdivided chambers
stantial portion of the'cross-section of the en
trance tube SI and projects somewhat into the in,
terior of "the chamber 90. f (The annular space
between the cylindrical parts 91 and 9| islcngi
tudinallyv subdivided " by partitions
apply without substantial modi?cation to the ar
rangement of Fig; 10. That is to say, the elec
tron stream E will, if the dimensions of thesys
tem are properly correlated to the stream veloc
ity and to the desired operating frequency,‘ be
modulated‘ at the gaps which it ?rst traverses and
IMF-best 75 will release a portion of its energy to the sur~
2,403,795
11
12
as a result of its mutual reaction with the elec
rounding structure at the gaps which it traverses
tron stream-except in so far as the stream may
near the end of its path. The oscillatory energy
be modulated prior to its. entranceinto the cham
thus developed within the vchamber may be uti
ber. Such excitation of they chamber I64 as oc
lized by the provision of a suitable output circuit
curs. will be a result of the prior modulation of
(not shown).
the electron stream by the electrode I54 and will
The various structures which have been de
be proportional to the amplitude of such modu
scribed in the foregoing have been illustrated as
lation. However, the strength of the waves de
being of cylindrical character. It is to be under
veloped within the chamber I64 as a result. of its
stood, however, that this isnot an essential at
excitation by the modulated stream. may be very
tribute of the invention and that other cross
much greater than the strength of the received
sectional forms may be adopted. For example,
signal wave, thereby permitting ampli?cation ef
Figs. ‘11 and 12 represent, respectively, a cross
fects to be obtained. The ampli?edenergy de
sectional view and a partial longitudinal section
veloped within. the chamber, may be effectively
of a chamber which, externally viewed, is of
square con?guration. It comprisesv a conductive 15 utilizedby the provision of a couplingloop 1.66
Provided at an appropriate locationv within-the
enclosure I40 and a pluralityof transverse con
chamber'and having an external connection I61
ductive partitions, of which those shown are num
adapted ,for coupling toa. suitable utilization de-._
bered I 4| and I42. This construction, which in
vice such asa detector (not shown).
- 1,
its complete form may be assumedt'to be generally
Althoughthe invention. has been exempli?ed
similar to the tube shown in Fig. l (except for
by reference to. devices operated with a pure elec
its cross-sectional con?guration), may be expect
tron discharge, it should be understoodvthat. the
ed' to operate in a manner generally analogous
principles set forth are applicablein their gen-.
to that speci?ed in-connection with the former
eral aspects to other. types of charged particles.
construction, vdue allowance being made in the
calculation of resonant frequency for the differ 25 For example, results generally similar to those
ent boundary conditions imposed by the shape in
volved.
Still other and more, complex con?gurations,
such as chamber of oblate cross-section, may also
be employed.
‘
described may be obtained by the useofla positive
ion stream cooperating with. structures of the
character referred to herein.
Moreover, while the vinvention has. been de
30 scribed in connectionwith particular structures
Furthermore, while the. invention has soyfar
been described solely in connection'with oscilla
tions adapted for the generation: and transmis
sion of high frequency waves, it is by no means
limited to this use and may be alternatively "em
ployed in' the ampli?cation and detection of re
ceived signals.‘ Fig. '13, for example,,schematical
' and in particular modes of use, it will be under.
stood that numerous modi?cations may bev made
by those skilledin the art without actually. de
parting from the, invention. I, therefore, aim
in the appended claims to cover all .such equiva—
lent variations as come within .. the. true spirit
and scope of the ioregoingfdisclosure.
What I claim as new andldesire to secure by
1y illustrates an ampli?er embodying a resonant
LettersPatentof the UnitediStates, is:
system of the general character of 'thatillustrat
1. In combination, an elongated hollow con
40
ed in Fig. 1.
ductive'structurea succession of discontinuities
The structure'referred to comprisesan elongat
within the structure subdividing the enclosed
ed glass shaft portion I50 which encloses a cath
space into. a series of spacer-resonant sections
ode I5I, a- focusing electrode I52 and a series of
aligned cylindrical electrodes I53'-I55,‘inclusive.
These latter electrodes are maintained atincreas
ingly positive potentials. by appropriate‘ connec
which are individually resonant.’ at a common
45 frequency, all-the bounding surfacesof the vari
oussections being electricallyinterconnected by
low resistance paths and there being a passage
tion-to a battery 'I 51.
way extending longitudinally of vthe; structure for
The central electrode I54. is subjected toahigh
spatially interconnecting the-sections, andmeans
frequency signal which may be-derived, for ex
ample, from an. antenna I59. and which is ap 50 for projecting. charges through the ' said. passage
way to produce energy conversion effects by mu
plied to the electrodethrough an appropriate .cir
tual reaction of, the said charges and the said
cuit; illustrated diagrammatically as. comprising
resonant sections.
the. parallel combination of ' an inductance. I60
2., In combination, an elongated hollow con
and a capacitance IBI. Asa resultof'the, poten
tial variations of the electrode I54, the electron .55 ductive structure, a, succession ofv conductive ele
ments, positioned at. regularly’ spaced intervals
stream proceeding from the cathode. I5I will ob
withinthe structure and. having extensions in a
viously become velocity' modulatedas .it traverses
direction transverse to its, longitudinal axis. for
the-gaps between thiselectrode-and the electrodes
subdividing it into a series of. space.-=resonant
I 53 and I 55. With appropriate dimensions of the
electrode I54 the modulating effects may be made 60 sections, all the bounding surfaces. of the various
sections being electrically interconnected by low
cumulative at the twov gaps.
resistance paths and there being a passageway
After passage through the electrode I55, the
extending longitudinally of, ,thestructurefor spa
modulated electron stream-is projected into a
tially interconnecting the said sections, and
chamber I64 which is similar in structural form
to the chamber 20 of Fig. 1. However; the longi 65 means for projecting charges through the said
passageway to produce energy conversion effects
tudinal dimensions of the various subdivisions of
by mutual reaction of the said charges and the
the chamber I64..are preferably'made such as to
said resonant sections.
'
'
assure. that the electron transit time between
3. In. combination, a hollow continuously con-v
corresponding points in adjacent sections corre
ductive structure providing an elongated cham
sponds as nearly as possible to-an integral-num
ber of complete. cycles of potential variation, at
the. resonant frequency of the chamber. Under
these circumstances, and for reasons previously
given ‘herein, there willbelittle. tendency for .the
chamber to break into. self-sustained oscillations
ber, a plurality of conductive partitioning ele
ments positioned at regularly- spaced, intervals
along the length of the chamber and providing
gaps between the. elements, the said elements
subdividing thechamber into a plurality. orsim
2,403,795
13’
‘
-
ilar space-resonant sections each 'of which is in
dividually resonant at thesame ‘frequency, and
means for projecting charged particles succes
sively through the various sections and across
the said gaps to produce energy conversion ef
fects by virtue of the mutual reaction of the‘
said resonant sections and the said particles.
14
the resultant wave energy for use external to the
said chamber.
8. In combination, an elongated‘ hollow con
ductive structure, a series of axially aligned tu
bular conductive elements positioned within the
structure and, extending longitudinally thereof,
the said elements being mutually spaced to pro
vide gaps between their adjacent extremities, con
ductive wall partsextending between the said
ductive structure having inwardly projecting
conductive wall parts at regularly spaced inter 10 elements and the lateral walls of the said struc
ture for supporting the elements and for con
vals along the length of its interior surface, said
necting them electrically to the structure, said
wall parts effectively dividing the space enclosed
wall parts dividing the structure into a series of
by the structure into a series of similar space
similar resonant cavities which are connected
resonant sections each of which is individually
resonant at the same frequency, and means for 15 through the axial openings in the said tubular
elements, and means for projecting charged par
projecting a stream of charged particles succes
ticles successively through the said tubular ele
sively through the various sections to produce
ments and across the said gaps so, as to produce
energy conversion effects by the mutual reaction
energy conversion effects by the mutual reaction
of the said structure and the said stream.
5. A high frequency oscillator comprising 20 of the particles and'the said resonant cavities.
9. High frequency apparatus including a hol
means de?ning an elongated chamber of con- ,
low conductive structure de?ning an elongated
tinuously conductive character, a succession of
chamber, a series of axially aligned electrically
‘electrically connected conductive elements pro
connected conductive bodies supported centrally
viding recurrent discontinuities within the cham
within the said structure and extending longitu
ber along its length, said elements effectively di
dinally thereof, the said bodies being mutually
viding the chamber into a plurality of space-res
spaced to provide gaps between them and serv
onant sections each of which is individually res
ing to divide the said chamber into a plurality of
onant at the same frequency, the various sec
4. In combination, an elongated hollow con-v
similar space-resonant sections, each resonant at
tions being connected by a passageway extend- _
ing longitudinally of the chamber, means for 30 the same frequency, and means to project charged
projecting moving charges through the passage
particles longitudinally of the chamber in prox
way to generate electromagnetic waves within
imity to the said conductive bodies,'thereby to
' produce energy conversion e?ects resulting in the
the chamber by mutual reaction of the said
generation within the structure of high frequency
charges and the said resonant sections, and
means for abstracting a portion of the wave 35 electromagnetic waves.
energy thereby developed for utilization outsid
7' 10. High frequency apparatus including a hol
low conductive structure de?ning an elongated
the said chamber,
'
6. A high frequency oscillator comprising an » chamber, a series of axially aligned cylindrical
elongated hollow conductive structure having in
conductive bodies supported centrally within the
wardly projecting conductive wall parts at regu 40 said structure and extending longitudinally there
larly spaced intervals along the length of its
of, the said bodies being mutually spaced to pro
interior surface, said wall parts effectively divide
vide gaps between them and serving to divide the
me the space enclosed by the structure into a v said chamber into a plurality of similar sections,
series of similar space-resonant sections each of
each resonant at the same frequency, conductive
which-is individually resonant at a common fre-v 45 means materially smaller in diameter than the
quency, means for projecting a'stream of charged
said cylindrical bodies > for directly connecting
particles successively through the various sec
the various bodies along a line which is coinci
tions to generate high frequency electromagnetic
dent with their common axis, and means to pro
waves within the structure as a result of the
ject charged particles longitudinally of the cham
mutual reaction of the structure and the said 50 ber in proximity to the said conductive bodies,
stream, and means for abstracting a portion of
the resultant wave energy for utilization outside
thereby to maintain the chamber in a condition
the structure.
reaction, of the charged particles and the various '
,
.
of resonant excitation by virtue of the mutual
'7. High frequency apparatus comprising a con
conductive components of the apparatus.
tinuously conductive structure which de?nes an 55
11. High frequency apparatus comprising a hol
elongatedchamber, a succession of conductive ele- V low conductive structure de?ning an elongated
ments providing recurrent discontinuities within
chamber and having inwardly projecting con
the chamber along its length, said elements ef
ductive wall parts at regularly spaced intervals '
fectively dividing the chamber intow'a plurality
along the length of its interior surface, a series
of space-resonant sections each of which is in 60 of electrically connected conductive bodies sup-v
dividually resonant at the same frequency, the
ported centrally within the chamber, said bodies
various sections being connected'by a passage
corresponding in number and axial distribution
way extending longitudinally of the chamber, and
there being an opening in the said chamber of
such constricted dimensions as to inhibit the
propagation through the opening of electromag
netic waves of the said frequency, means includ
ing a cathode outside the chamber for projecting
to the said wall parts and serving in cooperation
with the wall parts to divide the chamber into a
series of similar space-resonant sections which
are individually resonant at the same frequency
and which are connected through spaces existing
between the respective bodies and the adjacent
electrons longitudinally of‘the chamber through
the said opening and passageway, thereby to» 70 wall parts, and means for projecting charged
particles successively through the various sections,
maintain the chamber as a whole in a state of
thereby to maintain the said structure in a state
resonant excitation by the generation within it
of resonant excitation.
of electromagnetic waves of the said frequency.
C. HAHN.
and means for abstracting,” em a portion at
Документ
Категория
Без категории
Просмотров
0
Размер файла
1 487 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа