US3322993A - Getter body mounted on low thermal conductivity supports - Google Patents
Getter body mounted on low thermal conductivity supports Download PDFInfo
- Publication number
- US3322993A US3322993A US368674A US36867464A US3322993A US 3322993 A US3322993 A US 3322993A US 368674 A US368674 A US 368674A US 36867464 A US36867464 A US 36867464A US 3322993 A US3322993 A US 3322993A
- Authority
- US
- United States
- Prior art keywords
- getter
- cathode
- heat
- getter body
- thermal conductivity
- Prior art date
- 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
Links
- 230000005855 radiation Effects 0.000 claims description 4
- 150000002500 ions Chemical class 0.000 description 7
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- 239000010936 titanium Substances 0.000 description 5
- 229910052719 titanium Inorganic materials 0.000 description 5
- 238000010521 absorption reaction Methods 0.000 description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 239000001301 oxygen Substances 0.000 description 3
- 229910052760 oxygen Inorganic materials 0.000 description 3
- 238000012216 screening Methods 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 238000010894 electron beam technology Methods 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 2
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000003795 desorption Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 238000005247 gettering Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 239000011733 molybdenum Substances 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 239000010937 tungsten Substances 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J9/00—Apparatus or processes specially adapted for the manufacture, installation, removal, maintenance of electric discharge tubes, discharge lamps, or parts thereof; Recovery of material from discharge tubes or lamps
- H01J9/38—Exhausting, degassing, filling, or cleaning vessels
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J35/00—X-ray tubes
- H01J35/02—Details
- H01J35/20—Selection of substances for gas fillings; Means for obtaining or maintaining the desired pressure within the tube, e.g. by gettering
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J7/00—Details not provided for in the preceding groups and common to two or more basic types of discharge tubes or lamps
- H01J7/14—Means for obtaining or maintaining the desired pressure within the vessel
- H01J7/18—Means for absorbing or adsorbing gas, e.g. by gettering
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J7/00—Details not provided for in the preceding groups and common to two or more basic types of discharge tubes or lamps
- H01J7/14—Means for obtaining or maintaining the desired pressure within the vessel
- H01J7/18—Means for absorbing or adsorbing gas, e.g. by gettering
- H01J7/186—Getter supports
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J2235/00—X-ray tubes
- H01J2235/20—Arrangements for controlling gases within the X-ray tube
- H01J2235/205—Gettering
Definitions
- this is achieved by locating the getter within the cathode body of the X-ray tube in the neighbourhood of the hot cathode without heat-conductiviely connecting it to the cathode or its body so that the getter is heated exclusively by heat radiation from the cathode to a temperature of at least 600 C. in order to transmit to the getter the maximum of heat by heat radiation.
- FIG. 1 shows a cross section of the X-ray tube in a plane perpendicular to the heating filament and, FIG. 2 a cross section in a plane containing the heating filament.
- a getter 3 composed of titanium sheets is placed within the cathode body 1 of an X-ray tube close to the hot cathode 2 to be heated by its radiated heat.
- the getter 3 is suspended on a tungsten Wire 4, which extends in a supporting body 5 and is relatively thin, in order to at least practically prevent any heat transmission to the cathode body 1.
- the supporting body 5 of the getter 3 is inserted into a lateral opening of the cathode body 1.
- the getter 3 composed of a number of titanium sheets is protected by a tubular screening body 6 of a metal having less afiinity to oxygen than titanium in order to prevent atoms released by quick ions to reduce oxides of the glass of the X-ray tube.
- An advantage of my new construction is the small heat transfer between the getter 3 and the cathode body 1 and consequently the mainice tenance of the possibly highest temperature, say at least 600 C., of the getter 3 exclusively by heat radiated by hot cathode 2.
- the heat conductivity of the getter supports 4, 5 should be chosen so, that the temperature of the getter in the course of operation of the X-ray tube is maintained at or above about 600 C. to make the getter etfective even for absorption of nitrogen.
- a cathode body 1 including a directly heated cathode (2); a getter body (3) inside the tube close to but heat-conductively detached from the cathode (2) to be heated therefrom exclusively by radiated heat; and a support (4, 5) for the getter body at least practically heat-conductively separating the getter body from the cathode body (1) and thus saving the getter body from loss of heat received by radiation and maintaining its temperature at least at about 600 C.
- a high-vacuum tube according to claim 1 comprising a screening body (6) of a material of lower afiinity to oxygen than titanium, said screening body shielding the getter body (3) to prevent atoms released by quick ions from reducing oxides contained in portions of the tube.
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Vessels, Lead-In Wires, Accessory Apparatuses For Cathode-Ray Tubes (AREA)
Description
May 30, 1967 M. VINOPAL 3,322,993
YGETTER BODY MOUNTED ON LOW THERMAL CONDUCTIVITY SUPPORTS Filed May 19, 1964 IN VEN TOR.
United States Patent 3,322,993 GETTER BODY MOUNTED 0N LOW THERMAL CONDUCTIVITY SUPPORTS Miroslav Vinopal, Prague, Czechoslovakia, assignor to Chirana Praha, narodni podnick, Prague, Czechoslovakia, a corporation of Czechoslovakia Filed May 19, 1964, Ser. No. 368,674 Claims priority, application Czechoslovakia, May 23, 1963, 2,967/ 63 3 Claims. (Cl. 313-174) This invention relates to high vacuum tubes, primarily X-ray tubes, and more particularly to gettering means used in said tubes.
In X-ray tubes which have been evacuated to a high degree and sealed by melting olf the evacuating conduit, gases absorbed in materials within the tube are released, particularly during the operation of the tube and are removed continuously during said operation of the X-ray tube by ion absorbing means. The materials upon which quick ions generated in the electron beam of the X-ray tube impinge are inefiective getters and the absorption of the gas molecules is mostly not permanent. In the course of the life time of the X-ray tube, the desorption is frequently not in equilibrium with the absorption, so that the vacuum deteriorates. It is therefore necessary to use getter, which has to be heated to a relatively high temperature; such heating required an additional electric circuit in the X-ray device. It is an object of this invention to obviate such an additional electric circuit.
In accordance with this invention this is achieved by locating the getter within the cathode body of the X-ray tube in the neighbourhood of the hot cathode without heat-conductiviely connecting it to the cathode or its body so that the getter is heated exclusively by heat radiation from the cathode to a temperature of at least 600 C. in order to transmit to the getter the maximum of heat by heat radiation.
An embodiment of the invention is illustrated in the accompanying drawing wherein FIG. 1 shows a cross section of the X-ray tube in a plane perpendicular to the heating filament and, FIG. 2 a cross section in a plane containing the heating filament.
A getter 3 composed of titanium sheets is placed within the cathode body 1 of an X-ray tube close to the hot cathode 2 to be heated by its radiated heat.
The getter 3 is suspended on a tungsten Wire 4, which extends in a supporting body 5 and is relatively thin, in order to at least practically prevent any heat transmission to the cathode body 1. The supporting body 5 of the getter 3 is inserted into a lateral opening of the cathode body 1.
The getter 3 composed of a number of titanium sheets is protected by a tubular screening body 6 of a metal having less afiinity to oxygen than titanium in order to prevent atoms released by quick ions to reduce oxides of the glass of the X-ray tube. An advantage of my new construction is the small heat transfer between the getter 3 and the cathode body 1 and consequently the mainice tenance of the possibly highest temperature, say at least 600 C., of the getter 3 exclusively by heat radiated by hot cathode 2.
Quick ions generated in the electron beam of the X-ray tube impinge upon the getter of this design, and pass around the hot tungsten cathode 2. These ions cause the evaporation of material upon which they impinge. It is not desirable that the chemically very aggressive evaporated getter atoms attack for instance glass and it is therefore suitable to protect the place where the quick ions impinge by some material With smaller chemical afiinity to oxygen than titanium, for instance by molybdenum.
The heat conductivity of the getter supports 4, 5 should be chosen so, that the temperature of the getter in the course of operation of the X-ray tube is maintained at or above about 600 C. to make the getter etfective even for absorption of nitrogen.
While a specific embodiment of my invention has been shown and described to illustrate the application of the principles of my invention, it will be understood that the same may be otherwise embodied without departing from such principles.
In the appended claims which define my invention the reference characters are included to facilitate the reading of the claims with reference to the specification and drawing and they are not to be consideerd as limiting the scope of the claims.
I claim:
1. In a high-vacuum tube particularly an X-ray tube the improvement comprising in combination a cathode body 1) including a directly heated cathode (2); a getter body (3) inside the tube close to but heat-conductively detached from the cathode (2) to be heated therefrom exclusively by radiated heat; and a support (4, 5) for the getter body at least practically heat-conductively separating the getter body from the cathode body (1) and thus saving the getter body from loss of heat received by radiation and maintaining its temperature at least at about 600 C.
2. A high-vacuum tube according to claim 1 wherein said support comprises a stretched wire (4) of low heat conductivity holding the getter body in suspended position.
3. A high-vacuum tube according to claim 1 comprising a screening body (6) of a material of lower afiinity to oxygen than titanium, said screening body shielding the getter body (3) to prevent atoms released by quick ions from reducing oxides contained in portions of the tube.
References Cited UNITED STATES PATENTS 2,523,016 9/1950 Hamuas 313-180 2,900,549 8/1959 Doolittle 313174 X 2,948,607 8/1960 Wagener 313-174 JAMES W. LAWRENCE, Primary Examiner. S. A. SCHNEEBERGER, Assistant Examiner.
Claims (1)
1. IN A HIGH-VACUUM TUBE PARTICULARLY AN X-RAY TUBE THE IMPROVEMENT COMPRISING IN COMBINATION A CATHODE BODY (1) INCLUDING A DIRECTLY HEATED CATHODE (2); A GETTER BODY (3) INSIDE THE TUBE CLOSE TO BUT HEAT-CONDUCTIVELY DETACHED FROM THE CATHODE (2) TO BE HEATED THEREFROM EXCLUSIVELY BY RADIATED HEAT; AND A SUPPORT (4, 5) FOR THE GETTER BODY AT LEAST PRACTICALLY HEAT-CONDUCTIVELY SEPARATING THE GETTER BODY FROM THE CATHODE BODY (1) AND THUS SAVING THE GETTER BODY FROM LOSS OF HEAT RECEIVED BY RADIATION AND MAINTAINING ITS TEMPERATURE AT LEAST AT ABOUT 600* C.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CS296763 | 1963-05-23 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3322993A true US3322993A (en) | 1967-05-30 |
Family
ID=5368391
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US368674A Expired - Lifetime US3322993A (en) | 1963-05-23 | 1964-05-19 | Getter body mounted on low thermal conductivity supports |
Country Status (2)
| Country | Link |
|---|---|
| US (1) | US3322993A (en) |
| NL (1) | NL6405817A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0726592A1 (en) * | 1995-02-09 | 1996-08-14 | Picker International, Inc. | X-ray tube having a getter shield and method |
| US5734226A (en) * | 1992-08-12 | 1998-03-31 | Micron Technology, Inc. | Wire-bonded getters useful in evacuated displays |
| EP1494260A1 (en) * | 2003-06-30 | 2005-01-05 | Nucletron B.V. | Miniature X-ray source device |
| US9412550B2 (en) | 2011-07-04 | 2016-08-09 | Tetra Laval Holdings & Finance S.A. | Electron beam device, a getter sheet and a method of manufacturing an electron beam device provided with said getter sheet |
| US10748740B2 (en) * | 2018-08-21 | 2020-08-18 | Fei Company | X-ray and particle shield for improved vacuum conductivity |
| US10818466B1 (en) * | 2019-05-01 | 2020-10-27 | GE Precision Healthcare LLC | X-ray tube and cathode cup with deposition shield |
| US11972920B2 (en) | 2021-11-23 | 2024-04-30 | Fei Company | Vacuum compatible X-ray shield |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2523016A (en) * | 1948-12-30 | 1950-09-19 | Gen Electric | Getter supporting structure |
| US2900549A (en) * | 1957-06-20 | 1959-08-18 | Machlett Lab Inc | Getter for electron tube |
| US2948607A (en) * | 1957-10-25 | 1960-08-09 | Union Carbide Corp | Tantalum-titanium getter element |
-
1964
- 1964-05-19 US US368674A patent/US3322993A/en not_active Expired - Lifetime
- 1964-05-27 NL NL6405817A patent/NL6405817A/xx unknown
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2523016A (en) * | 1948-12-30 | 1950-09-19 | Gen Electric | Getter supporting structure |
| US2900549A (en) * | 1957-06-20 | 1959-08-18 | Machlett Lab Inc | Getter for electron tube |
| US2948607A (en) * | 1957-10-25 | 1960-08-09 | Union Carbide Corp | Tantalum-titanium getter element |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5734226A (en) * | 1992-08-12 | 1998-03-31 | Micron Technology, Inc. | Wire-bonded getters useful in evacuated displays |
| US5909202A (en) * | 1992-08-12 | 1999-06-01 | Micron Technology, Inc. | Wire-bonded getter in an evacuated display and method of forming the same |
| EP0726592A1 (en) * | 1995-02-09 | 1996-08-14 | Picker International, Inc. | X-ray tube having a getter shield and method |
| EP1494260A1 (en) * | 2003-06-30 | 2005-01-05 | Nucletron B.V. | Miniature X-ray source device |
| US7016471B2 (en) | 2003-06-30 | 2006-03-21 | Nucletron B.V. | Miniature X-ray source device |
| US9412550B2 (en) | 2011-07-04 | 2016-08-09 | Tetra Laval Holdings & Finance S.A. | Electron beam device, a getter sheet and a method of manufacturing an electron beam device provided with said getter sheet |
| US10748740B2 (en) * | 2018-08-21 | 2020-08-18 | Fei Company | X-ray and particle shield for improved vacuum conductivity |
| US10818466B1 (en) * | 2019-05-01 | 2020-10-27 | GE Precision Healthcare LLC | X-ray tube and cathode cup with deposition shield |
| CN111883407A (en) * | 2019-05-01 | 2020-11-03 | 通用电气精准医疗有限责任公司 | X-ray tube and cathode cup with deposition shield |
| US20200350137A1 (en) * | 2019-05-01 | 2020-11-05 | GE Precision Healthcare LLC | X-ray tube and cathode cup with deposition shield |
| CN111883407B (en) * | 2019-05-01 | 2023-11-14 | 通用电气精准医疗有限责任公司 | X-ray tube and cathode cup with deposition shield |
| US11972920B2 (en) | 2021-11-23 | 2024-04-30 | Fei Company | Vacuum compatible X-ray shield |
Also Published As
| Publication number | Publication date |
|---|---|
| NL6405817A (en) | 1964-11-24 |
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