close

Вход

Забыли?

вход по аккаунту

?

Патент USA US3031413

код для вставки
April 24, 1962
R. R. WARNECKE ETAL
3,031,399
HIGH-FREQUENCY UTILIZATION APPARATUS FOR IONIZED GAS
Filed Nov. 12. 1959
INVENTORS
Rob er!‘ R. WA R/VECKE e/
?deae malhe V/N ENT
BY
.4
ATTORNEYS
‘*nited tates atet
i
3,031,399
,
FOR IONIZED GAS
\
'
Robert R. Warnecke and Germaine Vincent, Paris,
France, assignors to Compagnie Generals dc Tele
'
l i
"
(Cl. 204-1932)
within a con?ned resonant space by means of which the
high~frequency electromagnetic ?eld is tuned to the reso
nant frequency thereof so as to effectively con?ne and
compress the gas.
These and other objects, features and advantages of‘the
present invention will become more obvious from the
following description when taken in connection with the
Filed Nov. ‘12, 1959, Ser. No. 852,268
Claims priority, application France Dec. 8, 1958
10 Claims.
Patented Apr. 24, 1962
2
HIGH-FREQUENCY UTILIZATION APPARATUS
graphic sans Fil, Paris, France ‘ "
3,31,399
accompanying drawing which shows in the single ?gure
’
thereof, for purposes of illustration only, an automatic
10 frequency control system for use with a prior art appa
The present invention relates to an apparatus in which
ratus for con?ning and compressing a heavily ionized
a strongly ionized gaseous medium is con?ned within an
gaseous medium.
.
evacuated vessel by’ means of a high-frequency electro
Referring now to the drawing which illustrates in the
magnetic ?eld, and more particularly to an apparatus pro
schematic diagram of the single FIGURE thereof the
vided with one or several‘ cavity resonators con?ning and 15 present invention in connection with a known prior art
compressing therein, by means of a high-frequency elec
arrangement, reference numeral 1 designates therein a
tromagnetic ?eld, a strongly ionized gaseous medium so
quartz tube in communication, ‘by means of conduit 2, with
as to effectively insulate the same from the walls of the
the source 3 for the admission or input of the gas and with
vessel to enable su?icient heating of the resulting so-called
the pump 4. The ends of the tube 1 are open or suitably
plasma with a goal to produce a thermo-nuclear fusion 20 perforated, and penetrate, in a vacuum-tight manner, into
reaction.v
the inside of cavity resonators 5 and ‘6. A high fre
Devices are known in the prior art of nuclear physics
quency electromagnetic ?eld is excited within the cavity
which include a casing or vessel ?lled with a strongly
resonators 5 andf6 by means of the energy produced, by
ionized gas, that is, in the status of plasma, which is sub
the high frequency generator or oscillator 7 and propa
jected to a con?ning action within a portion of this casing 25 gated or transmitted through the conduits or Wave guides
or vessel ‘for the purpose of compressing the same within
8 and 9 to the resonator cavities 5 and 6.
said portion, and, on the other hand, to thermally insulate
The frequency of the generator 7 is usually tuned to
or isolate the plasma from the walls of the casing or vessel
coincide with the resonant frequencies of the cavities 5
with a view to obtain an ei?cient heating of the plasma
and 6. The vessel or casing of the installation which is
30 evacuated is de?ned or delimited by means of windows 10
that may eventually lead to nuclear fusion reactions.
However, in the prior art devices utilizing a cavity
and 11 through, which the'electromagnetic energy may
resonator, di?iculties arise in the operation thereof due
?ow. The assembly is also placed in an axial magnetic
to the fact that the resonant frequency of the cavity
?eld produced by the windings or coils 12. The elements
changes in the course of the formation of the plasma. As
described so far hereinabove by reference to the single
the resonant frequency of the cavity undergoes changes, 35 ?gure of the drawing are all of known conventional
the ?xed frequency output from the oscillator producing
construction and may be realized in any manner known
the high-frequency electromagnetic ?eld at a predeter
in the prior art.
mined frequency no longer bears the desired relationship
to the resonant frequency of the cavity, i.e., the frequency
The operation of the prior art devices ‘described so far
hereinabove is as ‘follows:
of the electromagnetic ?eld set up within the cavity reso 40 After having admitted gaseous medium from the source
nator no longer corresponds to the resonant frequency
3 into the tube 1 and after having established a very low
of the cavity. It follows therefrom that as soon as the
pressure by means of the vacuum pump 4, a high-fre
high-frequency oscillator is not tuned to the resonant fre
quency electromagnetic ?eld is established within the
quency of the cavity, the e?‘iciency of the system decreases
cavities 5 and 6. This electromagnetic ?eld which is rela
by the reduction in the electromagnetic ?eld within the 45 tively intense since the generator 7 is tuned to the reso
resonator cavity which, in turn, decreases the compres
nant frequency of the cavities 5 and 6, thereby ionizes
sion effect on the plasma.
the gaseous medium present within the cavities 5 and 6
The present invention is concerned with a system im
whereupon the tube 1 ?lls‘ itself with plasma. The
proving the prior art devices and eliminating therefrom
plasma is thereby con?ned to the vicinity of the axis of
the shortcomings and disadvantages thereof mentioned
the tube 1 by the magnetic ?eld produced ‘by the coils 12.
hereinabove.
At the same time, as may be readily demonstrated theor
Accordingly, it is an object of the present invention to
etically as well as experimentally, the high-frequency ?eld
provide an apparatus for compressing a strongly ionized
exercises on the plasma a pressure which displaces the
gaseous medium within a cavity resonator by means of an
plasma from the cavities 5 and 6 into the tube 1. The
electromagnetic high-frequency ?eld which eliminates 55 density of the plasma thereby increases within the tube -'1
and obviates the inconveniences and shortcomings of the
and decreases correspondingly within the cavities 5 and 6-,
prior art devices and which also assures a relatively high
the corresponding'values thereof being relate-d to each
e?'iciency throughout the entire course of the operation
other. It also follows therefrom that the plasma is com
of the device and of the formation of the plasma.
pressed within the space thermally insulated from the
60
Another object of the present invention is the provision
walls of the tube 1, a space in which the plasma is con
of an apparatus for con?ning and compressing a strongly
?ned by the magnetic ?eld.
ionized gas within an enclosure formed by a cavity reso
However, experience also has clearly established that
nator by means of an electromagnetic ?eld which includes
the operation of such a prior art device is disturbed by
means to assure a continuous tracking of the output fre
the variation in the resonant frequency of the cavities 5
quency of the electromagnetic-?eld-producing oscillator 65 and 6 which is caused as the plasma is formed. Con
with the resonant frequency of the cavity Within which
sequently, the formation of the plasma entrains a detun
the gas is con?ned and‘compressed.
ing of the, cavities 5 and 6 with respect to the normally
Still another object of the present invention resides in
?xed output frequency of the generator 7 resulting in a
the provision of automatic frequency control means for
lowering or reduction of the high-frequency ?eld, a fact
use with the source producing a high-frequency electro 70 which may be very important.’ Furthermore, the com
magnetic ?eld in an apparatus of the type described
pression' of’ the plasma is very inet?cient as a result
hereinabove in which a strongly ionized gas is compressed
thereof;
3,031,399
3
ll
ing of the electromagnetic wave energy into an electric
signal usable as automatic frequency control are not lim
ited to the particular details described herein but may be
replaced by other means known to a person skilled in the
The present invention aims at an improvement over
such a prior art device by completely eliminating the dis
advantages encountered in connection therewith.
According to the present invention, the variations in the
art.
density of the plasma within tube 1 which, as pointed out
Thus, it is quite obvious that the present invention is not
hereinabove, are related to the variations in the density of
limited
to the details shown and described herein but may
the plasma within the cavities 5 and 6, a density upon
be varied and modi?ed considerably within the spirit and
which also depends the resonant frequency of the cavities
scope of the present invention, and we, therefore, do not
5 and 6, are utilized to derive therefrom a signal applied
to the high-frequency oscillation generator 7 which itself 10 wish to be limited to the details illustrated herein but in
tend to cover all such changes and modi?cations as are en
is of the type adapted to be electronically tuned in such a
compassed by the scope of the appended claims.
manner as to automatically re-tune the generator 7 to the
We claim:
resonant frequency of the cavities 5 and 6 by taking into
1. In an apparatus for compressing plasma, an evacu
consideration the presence of the plasma so that the de
tuning effect is effectively annulled and the high-frequency 15 ated vessel, means for admitting low pressure gas into said
vessel, at least one cavity resonator having its interior in
?eld within cavities 5 and 6, as well as the density of the
communication with said vessel, means for supplying high
plasma within tube 1, are retained at the maximum pos
frequency energy to said resonator to excite the same
Sible value thereof.
substantially at its natural resonance frequency thereby
The present invention also aims at a practical realiza~
ionizing
said gas to form plasma and pushing a part of
20
tion with simple means to translate the variations in the
said plasma away from said resonator into said vessel,
density of the plasma into an electrical signal adapted to
means for con?ning said plasma within the interior region
perform this control function.
of said vessel, and means responsive to the plasma density
The present invention will be better understood by ref
in said vessel for automatically retuning said high-fre
erence again to the single FIGURE of the drawing, and,
25 quency supplying means to the natural resonance fre
, in particular, to the elements thereof designated by refer
quency of said resonator with plasma contained therein.
ence numerals 13 to 19 which embody the present inven
2. A combination as claimed in claim 1, wherein said
tion as applied to the prior art device.
high-frequency supplying means is a backward wave oscil
As mentioned hereinabove, the generator or oscillator 7
lator.
is assumed to be of the type adapted to be electronically
tuned.
Any suitable oscillator may be used for that pur
pose, though the present invention proposes in particular
the use of a backward wave oscillator, known under the
3. A combination as claimed in claim 1, wherein said
returning means includes a beam source of microwave
energy, means for directing said microwave energy beam
through said plasma within said vessel, means for col
lecting said microwave energy after traversing said
to deliver an essentially constant power output over a rela 35
plasma,
whereby at least one of the variables consisting
tively large tuning band. A second generator 13 of any
of amplitude and phase of said microwave energy ex
suitable type and having a ?xed frequency is also provided
hibits a magnitude depending on said plasma density,
in accordance with the present invention, the output of
means for detecting at least one of said variables consist
which is transmitted through a wave guide 14 to a trans
ing of amplitude and phase to thereby obtain an elec
mitter horn 15 which, in turn, transmits a Well-de?ned 40 trical signal responsive to said plasma density, and means
beam of high frequency energy across the plasma within
for applying said signal to said cavity resonator high
the tube 1. A receiving horn 16 is disposed on the other
frequency supplying means to retune the same to a
side of the tube 1 which receives the electromagnetic wave
frequency corresponding to a plasma density maximum.
trade name of ‘*Carcinotron,” which offers the advantage
energy after having been subjected to an attenuation and
4. A combination as claimed in claim 1, wherein said
de-phasing in the course of its passage across the plasma 45 high-frequency supplying means is a backward wave os
within tube 1, this attenuation and dephasing being vari
cillator, and wherein said returning means includes a beam
able as a function of the density of the plasma. After de
source of microwave energy, means for directing said
tection of the received energy within a detector 17 which
microwave energy beam through said plasma within said
may be a simple recti?er or a phase-detector or discrim
inator circuit of any known type, as the case may be, a
signal is obtained at the output thereof which varies with
the density of the plasma. This output signal passes
through a circuit 18 having a suitable transfer function or
characteristic in order to adapt the law of the variations of
the detected signal varying as a function of the density of
the plasma within tube 1 to the law of frequency variation
as a function of the control voltage of generator 7, and is
thereupon applied by means of connection 19 to the input
circuit of the control electrode of the generator or oscilla
tor 7 in such a sense that the latter is re-tuned to the res
onant frequency of the cavities 5 and 6 under the condi
tions of the presence within the tube 1 of plasma having
vessel, means for collecting said energy after traversing
said plasma, whereby at least one of the variables thereof
consisting of amplitude and phase of said microwave en
ergy has a magnitude depending on said plasma density,
means for detecting at least one of said variables consist
ing of amplitude and phase in said energy to thereby ob
tain an electrical signal responsive to said plasma density,
and means for applying said signal to said backward wave
oscillator to electronically retune it to a frequency corre
sponding to a plasma density maximum.
5. In an apparatus for compressing an ionized gaseous
60 medium, comprising an evacuated vessel including cavity
resonator means, means for establishing a predetermined
pressure within said vessel and for regulatnig the presence
maximum obtainable density when this tuning is realized.
of said gaseous medium Within said vessel, means for sup
The present invention results in a considerable improve~
plying to said cavity resonator means high-frequency elec
ment in the performance of the prior art device of the type 65 tromagnetic energy at the resonant frequency of said cavity
described herein.
resonator means to thereby enable the production of
However, it is understood that the present invention is
plasma from said ionized gaseous medium within said ves
not limited to the details shown and described herein but
sel, and means operatively connected with said high-fre
is susceptible of many changes and modi?cations within
quency energy supplying means for automatically adjust
the scope and spirit of the present invention. As men 70
ing the output frequency thereof in dependence on the
tioned hereinabove, any suitable known circuits or devices
density of the plasma within said vessel to provide con
may be used to achieve the desired result in connection
tinuous correspondence between said resonant frequency
with elements 13 to 19. Additionally, the described
means translating the variations in the density of the
plasma as evidenced by the attenuation and/or de-phas
and said output frequency.
'
6. In an apparatus for compressing a strongly ionized
3,031,399
5
6
gaseous medium, comprising an evacuated casing includ
ing cavity resonator means, means for regulating the pres
pressure and presence of said gas within said casing, means
sure and presence of said gaseous medium within said cas
ing, means for supplying to said cavity resonator means
high-frequency electromagnetic wave energy at the reso
quency electromagnetic energy "at the resonant frequency
thereof to thereby ionize said gas therewithin and enable
nant frequency of said cavity resonator means to thereby
ionize said gaseous medium and enable the ‘formation of a
plasma within a predetermined portion of said casing,
and means operatively connected with said high-frequency
for supplying to said cavity resonator means high~fre
production of plasma therefrom, means for con?ning said
plasma Within said space means, and means operatively
connected with said high-frequency energy supplying
means for automatically adjusting the output frequency
thereof in dependence on the density of the plasma within
energy supplying means for automatically adjusting the 10 said portion to provide correspondence between said
output frequency thereof in dependence on the density of
resonant frequency and said output frequency.
the plasma to provide tracking between changes in said
10. A method for continuously obtaining maximum
resonant frequency and the output frequency of said high
plasma conditions in an evacuated casing having a cavity
frequency energy supplying means.
'
' resonator which is supplied with high-frequency electro
7. In an apparatus according to claim 6,‘ wherein said 15 magnetic energy from a high-frequency energy generating
last-mentioned means includes means for directing electro
device the output frequency of which essentially coincides
with the resonant frequency of the cavity resonator, com
prising the steps of transmitting a signal of high-frequency
wave energy as a function of the density of said plasma,
energy through the plasma to detect changes in the density
means for receiving the electromagnetic energy after pas 20 thereof re?ecting changes in the resonant frequency of the
sage through said plasma portion and for detecting the
cavity resonator, and, adjusting the output ‘frequency of
changes in said characteristics to thereby produce a con~
the high-frequency generating device as indicated by the
trol signal, and means for applying said control signal
changes in said signal to retune the generating device to
to said high-frequency energy supplying means to thereby
the frequency of said cavity resonator.
magnetic wave energy through a portion of said plasma
to thereby vary the characteristics of the electromagnetic
retune the same to the resonant frequency of said cavity
resonator means.
8. In an apparatus according to claim 5, wherein said
high-frequency energy supplying means includes a back
Ward wave oscillator adapted to be electronically tuned
over a wide band.
9. In an apparatus for compressing strongly ionized
gas, comprising an evacuated casing including cavity reso
nator means and space means for the formation of a
plasma from said ionized gas, means for regulating the
References Cited in the ?le of this patent
Australian J. of Physics, vol. 10, No. 1, March 1957,
pp. 221-225 (an article by Knox), 204-1545.
30
Proceedings of the Second United Nations International
Conference on the Peaceful Uses of Atomic Energy.
Held in Geneva, September 1-13, 1958. Vol 32, United
Nations, Geneva, 1958. An article by Vendeneove et al.,
pp. 239-244.
Документ
Категория
Без категории
Просмотров
0
Размер файла
549 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа