US2733350A

US2733350A - Calutron control circuit

Info

Publication number: US2733350A
Authority: US
Publication date: 1956-01-31
Anticipated expiration: 1973-01-31

Description

Jan. 31, 1956 K. R. MaCKr-:NZIE ET AL 2,733,350

CALUTRON CONTROL CIRCUIT 2 Sheets-Sheet l Filed Aug. l5, 1946 .N UTY INVENToRs. /ffA/A/frf/ MAC Kf/vz/E ATTORNEY Jan. 31, 1956 K, R MacKENz|E ET AL 2,733,350

CALUTRON CONTROL CIRCUIT 2 Sheets-Sheet 2 Filed Aug. l5, 1946 d ATTORNEY United States Patent() 2,733,350 CALUTRON CONTROL CIRCUIT Kenneth R. MacKenzie, Richmond, and William M. Brobeclr, Berkeley, Calif., assignors to the United States of merica as represented by the United States Atomic Energy Commission Application August 15, 1946, Serial No. 690,803 7 Claims. (Cl. Z50-41.9)

This invention relates to a protective arrangement for a calutron to prevent inadvertent overheating of watercooled structure of the calutron.

A calutron is an electromagnetic An object of this invention is to provide a calutron with apparatus for preventing the inadvertent overheating of parent to those skilled in the art to which it the following specification, claims, and drawing.

Referring to the drawing briefly,

Figure l is a schematic wiring diagram of an embodiment of this invention; and

Fig. 2 is a schematic wiring diagram embodying a modified form of this invention. Y

In order to prevent inadvertent overheating of watercooled structure of a calutron, the water supplies associated with these structures are interlocked with the electrical supplies which heat these structures.

In one modiiication of the invention all of the Water supplies of the calutron are interlocked with all of the calutron 16B of the vention has been applied, electrical networks. This tank 12 which is arranged 1n the air gan of an electromagnet (not shown) and by means of a vacuum pump The ion transmitter 15 illustrated here includes an ion source and an ion accelerating electrode struc 2 ture 30. The collector 16 is provided with two pockets 17 and 18 in which Inonoisotopically enriched material is to be collected.

The ion source 20 comprises a charge chamber 21 and an c chamber 22 communicating therewith, two corref respectively assoing bushing. The thermioncally emissive cathode 25 Vis supported above the arc chamber by means of two

rigid leads

28, 28 extending through and insulated fromv the wall of the tank 12. The ion accelerating structure 30 includes two spacedapart electro es 31, 31 forming a beam dening slitV 32 during operationQ A C-shaped liner 40 is arranged within the tank 12, the axis of the liner 49 and the axis of the tank 12 being substantially parallel. One end of the liner 40 is arranged in collector 16 in which ions operating.

The leads 28, 23 of the cathode 25 supporting the source arey water-cooled supplied through a rst'rnain conduit 50 including a rst valve 51 and a first flow switch 52 and through two branch and the arm 2 7 by means of water Connected to the outer ends of 27 and thence into the water sump.

charge end ofv this section 4 3 passes out through the. wall this section the C liner is cooled from end to end including the end adjacent the electrode structure 30.

The collector 16 is water-cooled by means of water supplied through a third main conduit 61 comprising two serially connected

sections

62 and 63 ioined together by means of an insulating coupling 64. The first section 62 is arranged externally of the tank 12 and includes a third valve 65 and a third flow switch 66. The second section 63 extends through the wall of the tank 12 and is insulated therefrom and is arranged in heat exchange relation with the collector 16. The discharge end of this section 63 likewise passes out through the wall of the tank 12. When cooling water is flowing through this section the collector 16 is cooled.

In the calutron illustrated here, the ion source is electrically connected to the wall of the tank 12 and is grounded and the accelerating electrode structure and the C liner and the collector 16 are insulated from the tank wall so that they may be maintained at a high negative potential with respect to ground in a manner hereinafter set forth.

In order to strike an arc in the are chamber 22 and to control it in a suitable manner electrical power is supplied to the

heaters

23 and 24 associated with the charge chamber 21, the arc chamber 22, and also to the thermionically emissive cathode 25. The heating of the charge chamber 21 causes a charge of solid material previously placed therein to vaporize and flow into the arc chamber 22 where it becomes ionized and some of the ions formed are withdrawn through the slit 26 into the beam defining slit 32 in the accelerating electrode structure 30 and thence projected along arcuate paths to the collector 16. More particularly, the thermionically emissive cathode 25 and the two

electrical heaters

23 and 24 and the two

electrical heaters

33, 33 are supplied power through corresponding first, second, third, and

fourth power supplies

70, 80, 90 and 100 respectively associated therewith.

The first power supply includes a manually operable switch 72, a variac 74, and an isolation transformer arranged in the order named between the input '76 and the output 78 thereof. The second power supply 80 also comprises a manually operable switch 82, a variac 84, and an isolation transformer operatively connected in the order named between the input 86 and the output 8S thereof. 'Ihe third power supply 90 also comprises a manually operable switch 92, a variac 94, and an isolation transformer operatively connected between the input 96 and the output 98 thereof. And the fourth power supply 100 likewise comprises a manually operable switch 102, a variac 104, and an isolation transformer operatively connected in the order named between the input 106 and the output 108 thereof.

An arc voltage supply 110 having an input 112 and an output 114 is provided, the output of which is electrically connected between the wall of the arc chamber 22 and the cathode 25 so as to maintain the cathode 2S negative with respect to the arc chamber 22 by means of a suitable voltage of about fifty to two hundred volts.

There is also provided a regulated high voltage supply 120 having an input 122 and an output 124 adapted to produce a high D. C. voltage of the order of about 10,000 to about 20,000 volts. The output 124 of this power supply 120 is connected between the wall of the grounded arc chamber 22 and the accelerating electrode structure 30 so as to maintain the ion source 15 at a positive potential relative to the ion accelerating electrode structure 30.

Two filament supplies and 125 are associated with the arc voltage supply 110 and the regulated high voltage supply respectively.

The inputs 76, S6, 96, and 106 of the first, second, third, and

fourth power supplies

70, 80, 90, and 100 mentioned above are all connected to the main busses which are supplied power from the main power line 132 through the contacts 134 of a relay 136. The two filament supplies 115 and 125 are also connected to these busses 130 through a double pole single throw switch 126. The input 112 of the arc voltage supply 110 is connected to these busses 130 through an auxiliary double pole single throw switch 117 and the switch 126. ri`he input 122 of the regulated high voltage supply 120 is connected to these busses 130 through an auxiliary double pele single throw switch 127 and the switch 126. The coil 137 of the relay 136 is connected across the conductors 132 of the main power line through contacts of three serially connected microswitch ciernents (not shown) arranged in the three

flow switches

52, 46, and 66 respectively.

To complete the electrical control network associated with the calutron 10 there is provided a vacuum pump control circuit 140 having an input 142 and an output 144 and a magnet control circuit having an input 152 and an output 154. The

inputs

142 and 152 of these two circuits and 150 are directly connected to the conductors 132 of the main power line through corresponding double pole

single throw switches

147 and 157. The output 144 of the vacuum pump control circuit 140 is connected to the vacuum pump 14. The output 154 of the magnet control circuit 150 is connected to the coils (not shown) of the electromagnet in the gap of which the tank 12 is mounted.

In operation, in order to effect an isotopic enrichment and a collection of the enriched material, a charge of solid polyisotopic material is placed in the charge chamber 21 and the ion source 15 is mounted in a standard manner within the tank 10. The switches 147 associated with a vacuum pump control circuit 140 is then closed, thus energizing the vacuum pump 14 and initiating evacuation of the tank 12. After the pressure within the tank has been reduced to a suitably low value of the order of l0JL mm. Hg, the switch 157 associated with the magnet control circuit 150 is energized, thereby establishing a magnetic field through the tank 12.

The

valves

51, 45, and 65 in the three

water conduits

50, 41 and 61 are then opened. When the first valve 51 is opened, cooling water circulates through the squirt tubes 28, 2i; and through the section of the conduit 55 arranged on the bushing 27. When the second valve 45 is opened cooling water circulates through the section 43 of the conduit 4.1 in thermal contact with the C-shaped liner 40. When the third valve 65 is opened cooling water circulates through the section 63 of the conduit 61 in thermal contact with the collector 16. When the rates of flow of cooling water in the three conduits are thus established at rates exceeding selected corresponding predetermined values, the microswitc'nes (not shown) in the three

flow switches

52, 46 and 66 are closed thus completing the circuit including the coil 137, thus energizing the relay 136. When the relay 136 is thus energized the contacts 134 close and the busses 130 are electrically connected to the conductors 132 of the main power line, thus preparing the four

power supplies

70, 80, 90 and 100 and the arc voltage supply 110 and the regulated high voltage 120 and the filament supplies 115 and 125 for operation. The

switches

72, 02, 92, and 102 of these four

power supplies

70, 30, 90, and 100 are then selectively closed at will, thereby causing electrical energy to ow to the thermionieally emissive cathode 25 and the four

heaters

23, 24, and 35, 33, the amount of heat supplied thereto being regulated by adjustment of the

corresponding variacs

74, 84, 94, and 104. The switch 126 is then closed thus energizing the iilament supplies 115 and 125 and the switch 117 is then closed thus establishing an electron accelerating voltage between the cathode 25 and the arc chamber 22 and causing ionizing electrons to be projected into the vapor in the arc chamber 22. When an arc of suitable strength and stability is thus established in the arc chamber 22, the switch 127 is closed, thus causing the regulated voltage supply 120 to become energized and thus establishing an ion accelerating field between the ion source 15 and the accelerating electrode structure 30. When this eld has been established, some of the ions tural elements of the ca n alternative e the manner in which the inputs of some of the volt power supplies are connected to'thc main More particularly,

are voltage supply 1 age supplies and 112, 76, s6, and 96er the e lirst, second and third termined rate the nncroswitch (not shown) in the second liow switch 46 is closed, thus completing the circuit including the coil 132 of the second relay 181 and thus ener iz,- ing this relay 181. When this relay 181 is thus energized, the contacts 180 close and the input 106 of the fourth When the above-referred to circuits have been prepared for operation, the switches 82, 92, and 162 of the second,

' third, and fourth power supplies 86. 90, and 100 are closed power supplies 70, 80 164) which are in tur re connected to the busses of the main pow' d relay 131. The coil 1 the conducto uctors 132 of the p circuit 14% vand t operated in the m is closed thus ener- `25. The valves its are then opened.

control circuit 150 are first above described and the s gizing the iilament d through' a portion of hing 27. When the rate h the Water-cooled elethrough the sq the conduit 55 ranged on the bus thereby causing electrical energy to flow to the four heaters 23,

V

24, and 33, 33. The amount of heat supplied to these four heaters may be regulated by adjustment of the'corresponding variacs 84, 94, and 104. When the vapor pressure in the arc chamber 22 is brought to a suiciently high value the switch 128 is closed if it is open, thereby energizing the tilamentsupplies 115 and 125. The switch 72A of the first power supply 70 is then closed, thereby causing electrical energy to iiow to the thermionically emissive cathode 25. When this cathode 25 has been brought to a suiiiciently high temperature the switch ate paths through the `tank 12 to the collector 16 where monoisotopically enriched materials derived from the polyisotopic charge material are separately collected in enveloping relationship thereto whereby said paths are electrostatically shielded from said ion accelerating means, ion source cooling means including a conduit arranged in heat exchange relationship with said structure associated with said ion source, liner structure cooling means including a conduit arranged in heat exchange relationship with said liner structure, receiver cooling means including a conduit arranged in heat exchange relationship with said receiver, a voltage supply associated with said ion accelerating means, are generating means associated with said ion source, and means controlled by flow of a cooling medium through said three conduits at rates in excess of corresponding predetermined rates for preparing said are generating means and said voltage supply for operation, whereby an arc may be established in said ion source and ions may be withdrawn therefrom and projected along said paths only when the rates of tlow of the cooling medium through said conduits exceed said predetermined rates.

2. In a calutron having an evacuated tank disposed in a magnetic field, an ion source and associated structure disposed in said tank, an ion receiver disposed in said tank, an accelerating means including electrode structure disposed adjacent said ion source adapted to transmit selected ions from said ion source through said magnetic eld along predetermined paths to said receiver, liner structure connected to said accelerating electrode structure and disposed in said tank along said paths in enveloping relationship thereto whereby said paths are electrostatically shielded from said ion accelerating means, ion source cooling means including a conduit arranged in heat exchange relationship with structure associated with said ion source, liner structure cooling means including a conduit arranged in heat exchange relationship with said liner structure, receiver cooling means including a conduit arranged in heat exchange relationship with said receiver, arc generating means for creating ions in said ion source, a voltage supply associated with said ion accelerating structure, means controlled by ow of a cooling medium through said ion source cooling means at a rate in excess of a predetermined rate for preparing said arc generating means for operation whereby an arc may be established in said ionsource only when the rate of tlow of cooling medium through the ion source cooling means exceeds said predetermined rate, and means controlled by flow of cooling medium through both said liner cooling means and said receiver cooling means at rates in excess of corresponding predetermined rates for preparing said voltage supply or operation whereby ions may be withdrawn from said ion source and projected along said paths only when the rates of ilow of the cooling medium through the conduits arranged in heat exchange relationship with said liner and with said receiver exceed said corresponding predetermined rates.

3. In a calutron having an evacuated tank disposed in a magnetic field, an ion source and associated structure disposed in said tank, an ion receiver disposed in said tank, ion accelerating means including electrode structure disposed adjacent said ion source adapted to transmit selected ions from said ion source through said magnetic field along predetermined paths to said receiver, liner structure connected to said accelerating electrode structure and disposed in said tank along said paths in enveloping relationship thereto, whereby said paths are electrostatically shielded from said ion accelerating means, ion source cooling means including a conduit arranged in heat exchange relationship with structure associated with said ion source, liner structure cooling means including a conduit arranged in heat exchange relationship with said liner structure, receiver cooling means including a conduit arranged in heat exchange relationship with said receiver, arc generating means for creating ions in said ion source, heating means arranged in heat exchange relationship with said ion accelerating structure, a voltage supply associated with said ion accelerating means, means controlled by flow of a cooling medium through said ion source cooling means at a rate in excess of a predetermined rate for preparing said arc generating means for operation whereby an are may be established in said ion source only when the rate of iiow of cooling medium through the ion source cooling means exceeds said predetermined rate, means controlled by the ilow of cooling medium through said liner cooling means at a rate in excess of a corresponding predetermined ratc for preparing said heating means for operation whereby said ion accelerating structure may be heated only when the rate of ow of cooling medium through the conduit associated with said liner structure exceeds said corresponding predetermined rate, and means controlled by ow of cooling medium through both said liner cooling means and said receiver cooling means at rates in excess of corresponding predetermined rates for preparing said voltage supply for operation, whereby ions may be withdrawn from said ion source and projected along said paths only when the rates of tlow of the cooling medium through the conduits arranged in heat exchange relationship with said liner and with said receiver exceed said corresponding predetermined rates.

4. In a calutron having an evacuated tank disposed in a magnetic field, an ion source disposed in said tank, an ion receiver disposed in said tank, ion accelerating means including electrode structure disposed adjacent said ion source adapted to transmit selected ions from said ion source through said magnetic eld along predetermined paths to said receiver, liner structure thermally connected to said accelerating electrode structure and disposed in said tank along said paths in enveloping relationship thereto, whereby said paths are electrostatically shielded from said ion accelerating means, liner structure cooling means including a conduit arranged in heat exchange relationship with said liner structure, heating means arranged in heat exchange relationship with said ion accelerating structure, a voltage supply associated with said ion accelerating means, and means controlled by the flow of cooling medium through said liner cooling means at a rate in excess of a predetermined rate for preparing said heating means and said voltage supply for operation whereby said ion accelerating structure may be heated and ions may be withdrawn from said ion source and projected along said paths only when the rate of ilow of the cooling medium through said conduit exceeds said predetermined rate.

5. ln a calutron having an evacuated tank disposed in a magnetic field, an ion source disposed in said tank, an ion receiver disposed in said tank, ion accelerating means including electrode structure disposed adjacent said ion source adapted to transmit selected ions from said ion source through said magnetic field along predetermined paths to said receiver, liner structure connected to said accelerating electrode structure and disposed in said tank along said paths in enveloping relationship thereto whereby said paths are electrostatically shielded from said ion accelerating means, liner structure cooling means including a conduit arranged in heat exchange relationship with said liner structure, receiver cooling means including a conduit arranged in heat exchange relationship with said receiver, a voltage supply associated with said ion accelerating means, and means controlled by tlow of a cooling medium through said two conduits at rates in excess of corresponding predetermined rates for preparing said power supply for operation whereby ions may be Jithdrawn from said ion source and projected along said paths only when the rates of flow of the cooling medium through said conduits exceed said predetermined rat` 6. In a calutron having an evacuated tank disposed in a magnetic t'ield, an ion source disposed in said tank, an ion receiver disposed in said tank, ion accelerating means including electrode structure disposed adjacent said ion source and adapted to transmit selected ions from source and adapted to transmit selected ions from said ion source through said magnetic field along predeter- No references cited.