US2267714A - Device for producing filters - Google Patents

Device for producing filters Download PDF

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Publication number
US2267714A
US2267714A US270858A US27085839A US2267714A US 2267714 A US2267714 A US 2267714A US 270858 A US270858 A US 270858A US 27085839 A US27085839 A US 27085839A US 2267714 A US2267714 A US 2267714A
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US
United States
Prior art keywords
foil
filters
producing
pores
lenses
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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US270858A
Inventor
Bodo V Borries
Ruska Helmut
Ardenne Manfred Von
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Fides Gesellschaft fuer die Verwaltung und Verwertung von Gewerblichen Schutzrechten mbH
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Fides Gesellschaft fuer die Verwaltung und Verwertung von Gewerblichen Schutzrechten mbH
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Publication of US2267714A publication Critical patent/US2267714A/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D67/00—Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
    • B01D67/0002—Organic membrane manufacture
    • B01D67/0023—Organic membrane manufacture by inducing porosity into non porous precursor membranes
    • B01D67/0032—Organic membrane manufacture by inducing porosity into non porous precursor membranes by elimination of segments of the precursor, e.g. nucleation-track membranes, lithography or laser methods
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B26—HAND CUTTING TOOLS; CUTTING; SEVERING
    • B26F—PERFORATING; PUNCHING; CUTTING-OUT; STAMPING-OUT; SEVERING BY MEANS OTHER THAN CUTTING
    • B26F1/00—Perforating; Punching; Cutting-out; Stamping-out; Apparatus therefor
    • B26F1/26—Perforating by non-mechanical means, e.g. by fluid jet
    • B26F1/31—Perforating by non-mechanical means, e.g. by fluid jet by radiation
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
    • H01J37/30—Electron-beam or ion-beam tubes for localised treatment of objects
    • H01J37/31—Electron-beam or ion-beam tubes for localised treatment of objects for cutting or drilling
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S164/00—Metal founding
    • Y10S164/04—Dental

Definitions

  • This invention relates to means for producing filters, in particular surface filters and ultrafilters.
  • the high-grade filters heretofore known including the ultra-filters employed in colloid chemistry, are depth filters; their filter pores extend not only straight through the filter material but also run and curve in other directions, and their diameters vary considerably along each pore and between the various pores.
  • the filter properties are usually not only determined by the dimensions of the pores but depend also on the psychochemical condition of the walls of the hb'l'efina" dil as to form the filters.
  • electrooptical lenses are preferably of the'elecdischage device for producing filters according to the invention.
  • the irradiation unit for producing the corpuscular rays may consist of a gas discharge tube of the cold cathode ray -oscillograph type or of a canal ray tube.
  • canal ray tubes are suitable which, due to a particular shape of the electrodes, emit a highly concentrated ion current.
  • anode cylinder oi a canal ray tube such a shape that the beam of ion rays is focussed before passing into the acceleration chamber and to have a magnetic field act on the ions in the neighborhood of the cathode in order to dissipate the secondary electrons released at the cathode.
  • Such arrangements have a relatively high output of rapidly flying ions and therefore are especially well suited for the purpose of the present invention.
  • Fig. 1 shows a longitudinal section through a Fig. 2 another embodiment also in a longitudinal section.
  • the source of the ion rays employed in both embodiments consists of a canal ray tube.
  • I denotes the anode of the ion current source; 2 the cathode, 3 the cathode aperture through which the gas chamber 4 communicates with the vacuum chamber 5.
  • the bottom 8 of the anode l is provided with an apercure I for the passage of the positive ions.
  • 8 and 9 are electric lenses which render the ion beam convergent and also accelerate the ions.
  • the illustration of a voltage divider ll, having several taps connected with the anode cylinder 1, the cathode 2 and the lenses 8 and 5, serves to indicate the relationship of the potentials applied to these elctrodes, all of which are positive as compared with the ground potential.
  • the ion ray impinges on the foil H as indicated at III.
  • A-vacuum vessel 13 encloses all of the above-mentioned electrodes and lenses.
  • the gas chamber 4 may be continuously supplied with gas, and the vessel 13 may be continuously evacuated in order to maintain the proper pressure conditions. It is preferable to I employ the same focal length for both accelerating converging lenses 8 and 9. In this case the positive ions are accelerated at both lenses approximately at the same rate.
  • the twolenses i4 and i5 are insulated from the grounded shields l8 and i9 surrounding the beam of ion rays, the other parts being substantially the same and designated by the same numerals as shown in Fig. 1.
  • the iocussed beam of ion rays emitted from the irradiating unit is accelerated and fo'cussed by the electrooptical lenses so as to have a sharply constricted cross section in the plane of incidence at the foil l i. Consequently, very great energy per unit of area is developed at the foil which is effective in burning a pore of the desired cross section through the foil.
  • the pores produced in this manner extend all in the same direction straight through the foil and have all the same diameter.
  • the adjustable device allows producing the pores in small and uniform distances from one another. The filters thus attain a high degree of uniformity and can be prepared in accurate accordance with various specifications.
  • a device for producing mechanical filters by providing a foil with filter pores comprising in a 5 vacuum vessel-irradiation means for producing a beam ot'charged corpusoles heavy as compared with electrons and of an intensity sumcient tor perforating said foil when in operation, a support for detachably holding said foil transverse to said 10 beam, eiectrooptical lens means and an adjust- -able energizing circuit connected with said lens means ior iocussing said beam to constrict said beam in the plane of incidence in accordance with the desired diameter or the filter pores to be '15 produced, and means for moving said foil supports laterally 01' said beam, said latter means being adjustable externally of said vessel, for changing the relative position of said foil and said beam to produce a multitude oi. pores. 2o
  • a device for producing mechanical filters by providing a foil with filter pores comprising in a vacuum vessel a canal ray tube for producing a beam of ion rays of an intensity sufilcient for perforating said foil when in normal operation, a 5
  • a device for producing mechanical filters by providing a toll with filter pores comprising in a vacuum vessel a canal ray tube for producing a beam of ion .rays of an intensity sufficient for perforating. said toil when in normal operation, said tube having an anode arranged and shaped so as to prefocus said beam, a support for detachably holding said foil transverse. to said beam, electrooptical means arranged between said tube and said support for focussing said beam onto said foil, and means for moving said foil supports laterally of said beam, said latter means being adjustable externally of said vessel, for changing the position of said support rela- .tive to said beam to produce a multitude of pores.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Optics & Photonics (AREA)
  • Mechanical Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Forests & Forestry (AREA)
  • Toxicology (AREA)
  • General Health & Medical Sciences (AREA)
  • Plasma & Fusion (AREA)
  • Health & Medical Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Filtering Materials (AREA)
  • Electron Sources, Ion Sources (AREA)

Description

MTRM- KR 292679714 Dec. 30, 1941.
2. v. BORRIES HAL; 2,257,714
DEVICE FOR PRODUCING FILTERS Filed April 29.. 1939 Patented Dec. 30, 1941 DEVICE FOR PRODUCING FILTERS Bodo v.- Borries, Berlin-Spandau, Helmut Ruska,
. Berlin-Nikolassee, and Manfred vonArdenne,
Berlin-Llchterfelde, Germany,
assignors to Fides Gesellschait fiir die Verwaitung und Verwertung von gewerbllchen Schutzrechtin mit beschrankter Haftung, Berlin, Germany, a corporation of Germany Application April 29, 1939, Serial N0. 270,853 in Germany April 30, 1938 3 Claims. (Cl. 250-154 This invention relates to means for producing filters, in particular surface filters and ultrafilters.
The high-grade filters heretofore known, including the ultra-filters employed in colloid chemistry, are depth filters; their filter pores extend not only straight through the filter material but also run and curve in other directions, and their diameters vary considerably along each pore and between the various pores. The filter properties are usually not only determined by the dimensions of the pores but depend also on the psychochemical condition of the walls of the hb'l'efina" dil as to form the filters. The
, fect on the charged corpuscular rays.
electrooptical lenses are preferably of the'elecdischage device for producing filters according to the invention, and
trostatic type because of their accelerating ef-\ However, magnetic lenses may also be employed, in which f u a case the total flux traversing a given section thereof must be relatively great owing to the small velocity of the heavy ccrpuscles. The irradiation unit for producing the corpuscular rays may consist of a gas discharge tube of the cold cathode ray -oscillograph type or of a canal ray tube. Above all, canal ray tubes are suitable which, due to a particular shape of the electrodes, emit a highly concentrated ion current. Thus, for instance, it has been proposed to give the anode cylinder oi a canal ray tube such a shape that the beam of ion rays is focussed before passing into the acceleration chamber and to have a magnetic field act on the ions in the neighborhood of the cathode in order to dissipate the secondary electrons released at the cathode. Such arrangements have a relatively high output of rapidly flying ions and therefore are especially well suited for the purpose of the present invention.
The invention will be more clearly understood from the following description of the embodiments diagrammatically shown in the drawing in which Fig. 1 shows a longitudinal section through a Fig. 2 another embodiment also in a longitudinal section. The source of the ion rays employed in both embodiments consists of a canal ray tube.
In Fig. 1, I denotes the anode of the ion current source; 2 the cathode, 3 the cathode aperture through which the gas chamber 4 communicates with the vacuum chamber 5. The bottom 8 of the anode l is provided with an apercure I for the passage of the positive ions. 8 and 9 are electric lenses which render the ion beam convergent and also accelerate the ions. The illustration of a voltage divider ll, having several taps connected with the anode cylinder 1, the cathode 2 and the lenses 8 and 5, serves to indicate the relationship of the potentials applied to these elctrodes, all of which are positive as compared with the ground potential. The ion ray impinges on the foil H as indicated at III. This foil is secured to a support l2 which may be displaced by means of an adjusting device l5 after a hole has been burnt in so that the entire foil is gradually provided with a multitude of tiny holes. A-vacuum vessel 13 encloses all of the above-mentioned electrodes and lenses. when in operation, the gas chamber 4 may be continuously supplied with gas, and the vessel 13 may be continuously evacuated in order to maintain the proper pressure conditions. It is preferable to I employ the same focal length for both accelerating converging lenses 8 and 9. In this case the positive ions are accelerated at both lenses approximately at the same rate.
In the embodiment shown in Fig. 2 the twolenses i4 and i5 are insulated from the grounded shields l8 and i9 surrounding the beam of ion rays, the other parts being substantially the same and designated by the same numerals as shown in Fig. 1.
In the above-described devices. the iocussed beam of ion rays emitted from the irradiating unit is accelerated and fo'cussed by the electrooptical lenses so as to have a sharply constricted cross section in the plane of incidence at the foil l i. Consequently, very great energy per unit of area is developed at the foil which is effective in burning a pore of the desired cross section through the foil. The pores produced in this manner extend all in the same direction straight through the foil and have all the same diameter. The adusting device allows producing the pores in small and uniform distances from one another. The filters thus attain a high degree of uniformity and can be prepared in accurate accordance with various specifications.
What is claimed is:
1. A device for producing mechanical filters by providing a foil with filter pores, comprising in a 5 vacuum vessel-irradiation means for producing a beam ot'charged corpusoles heavy as compared with electrons and of an intensity sumcient tor perforating said foil when in operation, a support for detachably holding said foil transverse to said 10 beam, eiectrooptical lens means and an adjust- -able energizing circuit connected with said lens means ior iocussing said beam to constrict said beam in the plane of incidence in accordance with the desired diameter or the filter pores to be '15 produced, and means for moving said foil supports laterally 01' said beam, said latter means being adjustable externally of said vessel, for changing the relative position of said foil and said beam to produce a multitude oi. pores. 2o
2. A device for producing mechanical filters by providing a foil with filter pores, comprising in a vacuum vessel a canal ray tube for producing a beam of ion rays of an intensity sufilcient for perforating said foil when in normal operation, a 5
support for detachably holding said I011 transverse to said beam, electrooptical means arranged between said tube and said support for focusing said beam onto said toil, and means for moving said 1011 supports laterally of said beam, said latter means being adjustable externally of said vessel, for changing the relative position of said foil and said beam to produce a multitude of pores. r
3. A device for producing mechanical filters by providing a toll with filter pores, comprising in a vacuum vessel a canal ray tube for producing a beam of ion .rays of an intensity sufficient for perforating. said toil when in normal operation, said tube having an anode arranged and shaped so as to prefocus said beam, a support for detachably holding said foil transverse. to said beam, electrooptical means arranged between said tube and said support for focussing said beam onto said foil, and means for moving said foil supports laterally of said beam, said latter means being adjustable externally of said vessel, for changing the position of said support rela- .tive to said beam to produce a multitude of pores.
BODO v.- BORRIES.
HELMUT RUSKA. Ma NFRED von ARDENNE.
Pv-w:
US270858A 1938-01-26 1939-04-29 Device for producing filters Expired - Lifetime US2267714A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DES130558D DE712434C (en) 1938-01-26 1938-01-26 Process for the production of pure surface filters and ultrafilters
DES131903D DE726710C (en) 1938-01-26 1938-05-01 Process for the production of pure surface filters and ultrafilters

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US270858A Expired - Lifetime US2267714A (en) 1938-01-26 1939-04-29 Device for producing filters

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DE (2) DE712434C (en)
FR (1) FR849313A (en)

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2420560A (en) * 1942-05-30 1947-05-13 Gen Electric Electron microscope
US2568112A (en) * 1946-12-24 1951-09-18 Csf Voltage divider for variable magnification electron microscopes
US2702274A (en) * 1951-04-02 1955-02-15 Rca Corp Method of making an electrode screen by cathode sputtering
US2778926A (en) * 1951-09-08 1957-01-22 Licentia Gmbh Method for welding and soldering by electron bombardment
US2793282A (en) * 1951-01-31 1957-05-21 Zeiss Carl Forming spherical bodies by electrons
US2819380A (en) * 1953-03-23 1958-01-07 Du Mont Allen B Lab Inc Method and apparatus for making apertured masks
US2902583A (en) * 1955-07-06 1959-09-01 Zeiss Carl Method for working materials by means of a beam of charged particles
US2915581A (en) * 1959-12-01 Method and apparatus for impressing
US2932720A (en) * 1964-04-15 1960-04-12 Commissariat Energie Atomique Metal welding methods
US2968723A (en) * 1957-04-11 1961-01-17 Zeiss Carl Means for controlling crystal structure of materials
US3009050A (en) * 1957-02-18 1961-11-14 Zeiss Carl Electron beam means for initiating chemical reactions
US3183391A (en) * 1960-12-16 1965-05-11 Rca Corp Shielding of electron gun from vaporized getter by decomposable foil over electrode aperture
US3320458A (en) * 1962-01-18 1967-05-16 Nippon Electric Co Cathode ray tubes employing a novel convergent electrostatic lens system for beam modulation
US3514666A (en) * 1967-06-16 1970-05-26 Avco Corp Charged particle generator yielding a mono-energetic ion beam
US3534385A (en) * 1965-12-08 1970-10-13 Centre Nat Rech Scient Process and apparatus for micro-machining and treatment of materials
EP0066685A1 (en) * 1981-06-10 1982-12-15 National Aeronautics And Space Administration Ion beam Sputter-etched ventricular catheter for hydrocephalus shunt

Families Citing this family (31)

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US2741719A (en) * 1950-09-27 1956-04-10 Rauland Corp Method and apparatus for inscribing a pattern in a target electrode structure
US2768751A (en) * 1951-02-10 1956-10-30 Wallace & Tiernan Inc Apparatus for filtration with finely divided filtering material
US2750524A (en) * 1951-11-15 1956-06-12 Mergenthaler Linotype Gmbh Perforate mask for multicolor television apparatus and method of producting same
DE1034786B (en) * 1952-02-27 1958-07-24 Zeiss Carl Fa Process for the manufacture of spinnerets
DE1100835B (en) * 1952-03-01 1961-03-02 Zeiss Carl Fa Device for milling profiles, for cutting templates or for drilling nozzle channels by means of a charge carrier beam
US2899556A (en) * 1952-10-17 1959-08-11 Apparatus for the treatment of substances
GB754866A (en) * 1953-04-15 1956-08-15 Heraeus Gmbh W C Improvements in or relating to spinning nozzles
US2816847A (en) * 1953-11-18 1957-12-17 Bell Telephone Labor Inc Method of fabricating semiconductor signal translating devices
IT598814A (en) * 1957-11-20
DE1064168B (en) * 1958-06-20 1959-08-27 Zeiss Carl Fa Device for generating and shaping a charge carrier beam
NL240710A (en) * 1958-07-01
US2952791A (en) * 1958-09-29 1960-09-13 Bbc Brown Boveri & Cie Electron beam lens
US3131143A (en) * 1959-11-17 1964-04-28 Technicon Instr Ultra-filtration apparatus and method
US3118050A (en) * 1960-04-06 1964-01-14 Alloyd Electronics Corp Electron beam devices and processes
US3082316A (en) * 1960-04-12 1963-03-19 Air Reduction Electron beam welding
US3150080A (en) * 1961-06-14 1964-09-22 Corn Products Co Dusting apparatus
US3303085A (en) * 1962-02-28 1967-02-07 Gen Electric Molecular sieves and methods for producing same
US3351731A (en) * 1962-10-23 1967-11-07 Jeol Ltd Method and apparatus for treating material with a charged beam
DE1292418B (en) * 1965-05-05 1969-04-10 Hermsdorf Keramik Veb Process for program control in the automatic processing of thin-film components in electrical engineering by means of a charge carrier beam
DE1654452B1 (en) * 1965-12-10 1971-01-14 Steigerwald Karl Heinz Dipl Ph Multi-layer artificial leather and process for its production
GB1125745A (en) * 1966-03-16 1968-08-28 English Electric Leo Marconi C Attaching integrated circuits to substrates
US3438504A (en) * 1966-08-11 1969-04-15 Gen Electric Filter element and method of production
US3482709A (en) * 1967-11-17 1969-12-09 Larson Co Charles O Inclined pegboard mounting displays
DE1963798A1 (en) * 1969-12-19 1971-06-24 Heinz Becker Artificial casing that is permeable to gas and water vapor for foodstuffs, especially sausage, and processes for their production
US3794174A (en) * 1972-01-11 1974-02-26 Atomic Energy Commission Porous metal insulator sandwich membrane
CH565020A5 (en) * 1973-04-03 1975-08-15 Filtrox Maschinenbau Ag
CH618612A5 (en) * 1975-12-31 1980-08-15 Berthold Schilling Dialysis membrane, in particular for haemodialysis, and process for production thereof
US4293414A (en) * 1978-05-04 1981-10-06 Ecodyne Corporation Slotted sheet filter element
DE3636481A1 (en) * 1986-10-27 1988-05-05 Altenburger Electronic Gmbh METHOD FOR PRODUCING MICRO TEST BODIES FOR PORE-SIZE MEASUREMENT IN ULTRA AND MICRO FILTERS, AND TEST BODIES PRODUCED THEREFORE
DE3742770A1 (en) * 1987-12-17 1989-06-29 Akzo Gmbh MICRO / ULTRAFILTRATION MEMBRANES WITH DEFINED PORO SIZE BY IRRADIATION WITH PULSE LASERS AND METHOD FOR THE PRODUCTION THEREOF
DE3915187A1 (en) * 1989-05-10 1990-11-22 Metallgesellschaft Ag FILTER ELEMENT FOR SEPARATING DUST FROM GAS

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2915581A (en) * 1959-12-01 Method and apparatus for impressing
US2420560A (en) * 1942-05-30 1947-05-13 Gen Electric Electron microscope
US2568112A (en) * 1946-12-24 1951-09-18 Csf Voltage divider for variable magnification electron microscopes
US2793282A (en) * 1951-01-31 1957-05-21 Zeiss Carl Forming spherical bodies by electrons
US2793281A (en) * 1951-01-31 1957-05-21 Zeiss Carl Drilling by electrons
US2702274A (en) * 1951-04-02 1955-02-15 Rca Corp Method of making an electrode screen by cathode sputtering
US2778926A (en) * 1951-09-08 1957-01-22 Licentia Gmbh Method for welding and soldering by electron bombardment
US2819380A (en) * 1953-03-23 1958-01-07 Du Mont Allen B Lab Inc Method and apparatus for making apertured masks
US2902583A (en) * 1955-07-06 1959-09-01 Zeiss Carl Method for working materials by means of a beam of charged particles
US3009050A (en) * 1957-02-18 1961-11-14 Zeiss Carl Electron beam means for initiating chemical reactions
US2968723A (en) * 1957-04-11 1961-01-17 Zeiss Carl Means for controlling crystal structure of materials
US3183391A (en) * 1960-12-16 1965-05-11 Rca Corp Shielding of electron gun from vaporized getter by decomposable foil over electrode aperture
US3320458A (en) * 1962-01-18 1967-05-16 Nippon Electric Co Cathode ray tubes employing a novel convergent electrostatic lens system for beam modulation
US2932720A (en) * 1964-04-15 1960-04-12 Commissariat Energie Atomique Metal welding methods
US3534385A (en) * 1965-12-08 1970-10-13 Centre Nat Rech Scient Process and apparatus for micro-machining and treatment of materials
US3514666A (en) * 1967-06-16 1970-05-26 Avco Corp Charged particle generator yielding a mono-energetic ion beam
EP0066685A1 (en) * 1981-06-10 1982-12-15 National Aeronautics And Space Administration Ion beam Sputter-etched ventricular catheter for hydrocephalus shunt

Also Published As

Publication number Publication date
DE726710C (en) 1942-10-19
US2267752A (en) 1941-12-30
DE712434C (en) 1941-10-18
FR849313A (en) 1939-11-21

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