US3668393A - Apparatus having evacuation spaces and a pumping assembly - Google Patents

Apparatus having evacuation spaces and a pumping assembly Download PDF

Info

Publication number
US3668393A
US3668393A US75883A US3668393DA US3668393A US 3668393 A US3668393 A US 3668393A US 75883 A US75883 A US 75883A US 3668393D A US3668393D A US 3668393DA US 3668393 A US3668393 A US 3668393A
Authority
US
United States
Prior art keywords
pump
space
turbomolecular pump
turbomolecular
high vacuum
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
Application number
US75883A
Other languages
English (en)
Inventor
Moriz Von Rauch
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Siemens AG
Siemens Corp
Original Assignee
Siemens Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority claimed from DE19691950328 external-priority patent/DE1950328C3/de
Application filed by Siemens Corp filed Critical Siemens Corp
Application granted granted Critical
Publication of US3668393A publication Critical patent/US3668393A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D19/00—Axial-flow pumps
    • F04D19/02—Multi-stage pumps
    • F04D19/04—Multi-stage pumps specially adapted to the production of a high vacuum, e.g. molecular pumps
    • F04D19/042—Turbomolecular vacuum pumps
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D19/00—Axial-flow pumps
    • F04D19/02—Multi-stage pumps
    • F04D19/04—Multi-stage pumps specially adapted to the production of a high vacuum, e.g. molecular pumps
    • F04D19/046—Combinations of two or more different types of pumps

Definitions

  • An apparatus has a high vacuum seal and at least one additional evacuative space as well as a pumping assembly for evacuating the vessel and space.
  • the pumping assembly has a backing pump and a turbomolecular pump having a main section communicating with the vessel and with the backing pump.
  • the turbomolecular pump has an auxiliary section communicating with the additional evacuative space and has a housing enclosing the main and-auxiliary sections.
  • the turbomolecular pump has first and second pump members disposed in the main and auxiliary sections respectively.
  • the housing includes a wall intermediate the main and auxiliary sections for separating the sections in vacuum tight relation to each other.
  • the turbomolecular pump has a rotor shaft which passes through the wall and connects the first pump member with the second pump member.
  • pump stands which include high vacuum pumps, mercury vapor beam pumps or oil diffusion pumps. With this type of pump stands, a vacuum in the region of 10 Torr is obtained.
  • turbo-molecular pumps which permit, producing, without a cooling trap, a hydrocarbon free high vacuum having a residual pressure in the region of to 10 Torr.
  • These pumps include, in a housing, a rotor shaft having a slotted disc; this rotor disc cooperates with correspondingly formed stator discs in such a manner that they form discharge channels for the gases evacuated from the high vacuum vessel.
  • turbomolecular pump arrangement having a main section that is connected between the high vacuum vessel and a backing pump arrangement.
  • the turbomolecular pump arrangement also has an auxiliary section whose input side is hermetically sealed from that of the main section and connected to the additional compartment.
  • the turbomolecular pump has first and second pump means that are included in the main and auxiliary sections respectively.
  • the housing encloses the main and auxiliary sections and includes a wall intermediate the two sections for separating the sections in vacuum tight relation to each other.
  • the turbomolecular pump arrangement has a rotor shaft which passes through the wall and connects the first pump means with the second pump means.
  • the invention permits the introduction of a turbomolecular pump generating a good high vacuum in a short time with high suction power.
  • the turbomolecular pump is useable also when several spaces have to be evacuated without the necessity of using additional pumps of this type. Oil vapors developed during rough pumping by the backing pump arrangement will not precipitate on the inner walls of the spaces being evacuated, even if cooling traps are omitted, because during the rough pumping of the high vacuum vessel or the other spaces, they are separated from the backing pump arrangement by the action of the turbomolecular pump arrangement.
  • the apparatus according to the invention uses a turbomolecular pump constructed with a housing which forms separate chambers surrounding respective active pump parts. It is often advantageous to expand a single part pump of the turbomolecular type so that the required number of auxiliary pump sections are added.
  • a corresponding variation of the invention is exemplified by expanding a one part turbomolecular pump so that the rotor shaft is extended on its end away from the drive motor and passes vacuum tight at this end through the end face of the housing of the one part pump and into an auxiliary section or chamber formed by a flange attached ancillary housing portion.
  • thermomolecular pump Aside from the special construction of the thermomolecular pump, there are advantages afforded by the incorporation of this type of pump.
  • a special advantage in the area of electron microscopes derives from the fact that turbomolecular pumps begin to develop appreciable suction when the pressure is in the region of 10" Torr, whereas conventional pumps have only a small suction power at these pressure values. Therefore, by using an auxiliary section of a turbomolecular pump, it is possible to effect a rough pumping of an airlock or other space of electron microscopes to a very low pressure.
  • a difficulty that arises, when providing for the evacuation of several compartments or spaces in an apparatus is that, in order to effect a rough pumping of any additional compartments, the backing pump must normally be disconnected from the turbomolecular pump and be connected via a by-pass with the additional compartments if the use of additional backing pumps are to be avoided. Such switching of the backing pump requires that there be provided a sufficiently large rough vacuum receiver to which the turbomolecular pump can be connected during the rough pumping of the additional compartments or spaces.
  • a two stage backing pump arrangement having a high vacuum stage and a rough vacuum stage.
  • the high vacuum stage is connected with its input to the main section of the turbomolecular pump, while the rough vacuum stage is connected permanently to the output of the high vacuum stage, and is connectable via a valve to the output of the auxiliary section of the turbomolecular pump arrangement.
  • the invention is applicable to any one of several apparatus, and without any limitations to the invention, the preferred application of the instant invention is to electron microscopes wherein the space containing the electron beam is the high vacuum vessel, while the additional spaces comprise the lock space and/or the desiccator.
  • the instant invention is appplicable wherever an additional space is provided as well as to apparatus having additional spaces to be evacuated.
  • FIG. 1 is a schematic diagram of the pertinent portions of an electron microscope equipped with a pumping apparatus according to the invention.
  • FIG. 2 is a schematic diagram of a vacuum pump arrangement wherein the pumping apparatus of the invention is provided with a two stage rotating fore-vacuum pump.
  • FIG. 1 shows simply the microscope column 1.
  • the microscope column of an electron microscope contains all the electro-optical equipment as well as the specimen in its investigative position.
  • the enclosed evacuative space defined by the microscope column is referred as the high vacuum vessel.
  • specimen lock 2 extends into the column. There can also be locks for diaphragms, cathodes or the like.
  • the specimen lock 2 with the lock space or compartment 3 contains an internal airlock'gate 4 and an external airlock gate 5 of which at least one airlock gate is always closed.
  • a neighboring vessel 6 belongs to the microscope which can, for example, be a desiccator for photographic material.
  • the vacuum line 7 communicates with the lock space 3 and the neighboring compartment or container 6.
  • Lock valves 8 and 9 are arranged on the vacuum line 7. Air inlet valves 10 and 11 are arranged on compartments 3 and 6 respectively.
  • the turbomolecular pump system of the invention is located at the lower portion of the high-vacuum column 1.
  • the system comprises a main section 12, a housing 13, rotor shafl 14, slitted discs 15 arranged on shaft 14 and the corresponding discs 16 constituting the stator of the pump.
  • this pump is arranged as a mu]- tipart pump in such a manner that an auxiliary section is provided by providing the rotor shaft 14 with an extension on the side away from its drive motor 17, that is, the rotor is extended toward the right in FIG. 1 as illustrated therein by the ancillary part 18.
  • the housing 13 is put together from two housing parts 19 and 20.
  • the main section of the pump system is included in housing part 19, the latter having an opening in the end face 21 for the rotor shaft 14.
  • Housing part includes the auxiliary section of the pump arrangement and is flange connected to part 19 in the region of end face 21.
  • the two housing parts 19 and 20 form chambers vacuum separated from each other of which the larger chamber communicates with the high vacuum vessel'l and the smaller chamber to the right communicates with the compartments 3 and 6 to be evacuated.
  • the paths of flow during pump operation are indicated by arrows in FIG. 1.
  • Output ports 22 and 23 serve for connection to a backing pump arrangement which is provided but not shown in FIG. 1.
  • FIG. 2 illustrates the two-stage backing pump arrangement used in'a preferred embodiment.
  • This pump arrangement has a high vacuum stage 30 and a rough vacuum stage 31. These two pump stages are connectable with the two sections 34 and 35 of a turbomolecular pump arrangement such as that shown in FIG. 1 via lines 32 and 33 respectively; these lines corresponding to the output ports 22 and 23 in FIG. I.
  • valves 36 and 37 are provided in the connecting lines 32 and 33 respectively, and the output of the high vacuum stage 30 is permanently connected to the input of the rough vacuum stage 31.
  • the input of the rough vacuum stage 31 is connectable at the input side either exclusively to the output of the high vacuum stage 30, or both to this output and to the auxiliary section 35 of the turbomolecular pump. This ensures that even during the rough pumping of airlocks and other auxiliary compartments, the main section 34 remains connected via the high vacuum stage 30 with the rough vacuum stage 31 of the backing pump arrangement.
  • Additional connectinglines may be, provided for other I facilities. Additional compartments or spaces may be formed by sectionalizing of the column of an electron microscope, for example.
  • turbomolecular pump having a main section and at least one auxiliary section and, likewise, other applications requiring other interconnecting lines.
  • additional evacuative spaces can also arise, for example, by the column of an electron microscope.
  • Apparatus having a high vacuum vessel and at least one additional evacuative space and equipped with a pumping assembly for evacuating said vessel and said space, said pumping assembly comprising a backing pump, and a turbomolecular pump having a main section communicating with said vessel and with said backing pump, said turbomolecular pump having an auxiliary section communicating with said additional evacuative space, said turbomolecular pump having housing means enclosing said main section and said auxiliary section, said turbomolecular pump having first and second pump means disposed in said main section and said auxiliary section respectively, said housing means including separation means intermediate said main section and said auxiliary section for separating said sections in vacuum tight relation to each other, said turbomolecular pump having a rotor shaft passing through said separation means and connecting said first pump means with said second pump means.
  • said turbomolecular pump comprising a drive motor attached to one end of said rotor shaft, said housing means comprising first and second housing parts surrounding said main section and said auxiliary section respectively, said second housing part being flange connected to said first housing part, and the other end of said rotor shaft extending vacuum tight through said separation means into said second housing part.
  • said backing pump being a two stage backing pump, one of said stages being a high vacuum stage, the input of said high vacuum stage being connected with said main section of said turbomolecular pump, the other one of said stages being a rough vacuum stage, the input of said rough vacuum stage being connected to the output of said high vacuum stage, and means connected between said input of said rough vacuum stage and the output of said auxiliary section of said turbomolecular pump for selectively connecting said rough vacuum stage to said auxiliary section.
  • said apparatus being an electron microscope, said vessel defining the space through which the electron beam passes and said one space being a lock space.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Non-Positive Displacement Air Blowers (AREA)
  • Compressors, Vaccum Pumps And Other Relevant Systems (AREA)
US75883A 1969-09-30 1970-09-28 Apparatus having evacuation spaces and a pumping assembly Expired - Lifetime US3668393A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19691950328 DE1950328C3 (de) 1969-09-30 Korpuskularstrahlgerät, insbesondere Elektronenmikroskop, mit einer aus Hoch- und Vorvakuumpumpen bestehenden Pumpenanlage

Publications (1)

Publication Number Publication Date
US3668393A true US3668393A (en) 1972-06-06

Family

ID=5747450

Family Applications (1)

Application Number Title Priority Date Filing Date
US75883A Expired - Lifetime US3668393A (en) 1969-09-30 1970-09-28 Apparatus having evacuation spaces and a pumping assembly

Country Status (4)

Country Link
US (1) US3668393A (enrdf_load_stackoverflow)
JP (1) JPS4814626B1 (enrdf_load_stackoverflow)
GB (1) GB1291353A (enrdf_load_stackoverflow)
NL (1) NL7010108A (enrdf_load_stackoverflow)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3969039A (en) * 1974-08-01 1976-07-13 American Optical Corporation Vacuum pump
US4057369A (en) * 1973-07-21 1977-11-08 Maschinenfabrik Augsburg-Nurnberg Ag Vacuum pump having a rotor supported in the interior of its casing
US4139774A (en) * 1977-02-09 1979-02-13 Hitachi, Ltd. Apparatus for irradiating a specimen by an electron beam
US4889995A (en) * 1987-12-23 1989-12-26 Hitachi, Ltd. Apparatus for analysis employing electron
US5228838A (en) * 1992-04-27 1993-07-20 Leybold Aktiengesellschaft Method for the evacuation of a low-vacuum chamber and of a HGH-vacuum chamber, as well as a high-vacuum apparatus for the practice thereof
US6238177B1 (en) * 1999-01-08 2001-05-29 Fantom Technologies Inc. Prandtl layer turbine
US6409477B1 (en) * 1999-07-05 2002-06-25 Pfeiffer Vacuum Gmbh Vacuum pump
EP1496263A2 (en) 2003-07-10 2005-01-12 Ebara Corporation Vacuum pump and semiconductor manufacturing apparatus
EP1589227A1 (fr) * 2004-04-21 2005-10-26 Alcatel Pompe à vide multi-étagée et installation de pompage comprenant une telle pompe
US20060216149A1 (en) * 2004-10-26 2006-09-28 Wilson Erich A Fluid Flow Channels in Bladeless Compressors, Turbines and Pumps
US20060291997A1 (en) * 2004-10-26 2006-12-28 Wilson Erich A Fluid Flow Chambers and Bridges in Bladeless Compressors, Turbines and Pumps
US20070020116A1 (en) * 2003-09-30 2007-01-25 Ikegami Mold Engineering Co., Ltd Vacuum pump
US20070092369A1 (en) * 2005-10-25 2007-04-26 Erich Wilson Bracket/Spacer Optimization in Bladeless Turbines, Compressors and Pumps
US20070274822A1 (en) * 2003-12-23 2007-11-29 Liu Michael C K Vacuum Pump

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS50139331U (enrdf_load_stackoverflow) * 1974-05-02 1975-11-17

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3483373A (en) * 1966-07-28 1969-12-09 Siemens Ag Airlock assembly for corpuscular ray devices
US3536418A (en) * 1969-02-13 1970-10-27 Onezime P Breaux Cryogenic turbo-molecular vacuum pump

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3483373A (en) * 1966-07-28 1969-12-09 Siemens Ag Airlock assembly for corpuscular ray devices
US3536418A (en) * 1969-02-13 1970-10-27 Onezime P Breaux Cryogenic turbo-molecular vacuum pump

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4057369A (en) * 1973-07-21 1977-11-08 Maschinenfabrik Augsburg-Nurnberg Ag Vacuum pump having a rotor supported in the interior of its casing
US3969039A (en) * 1974-08-01 1976-07-13 American Optical Corporation Vacuum pump
US4139774A (en) * 1977-02-09 1979-02-13 Hitachi, Ltd. Apparatus for irradiating a specimen by an electron beam
US4889995A (en) * 1987-12-23 1989-12-26 Hitachi, Ltd. Apparatus for analysis employing electron
US5228838A (en) * 1992-04-27 1993-07-20 Leybold Aktiengesellschaft Method for the evacuation of a low-vacuum chamber and of a HGH-vacuum chamber, as well as a high-vacuum apparatus for the practice thereof
US6238177B1 (en) * 1999-01-08 2001-05-29 Fantom Technologies Inc. Prandtl layer turbine
US6409477B1 (en) * 1999-07-05 2002-06-25 Pfeiffer Vacuum Gmbh Vacuum pump
EP1496263A2 (en) 2003-07-10 2005-01-12 Ebara Corporation Vacuum pump and semiconductor manufacturing apparatus
US20050025640A1 (en) * 2003-07-10 2005-02-03 Shinichi Sekiguchi Vacuum pump and semiconductor manufacturing apparatus
EP1496263A3 (en) * 2003-07-10 2010-02-10 Ebara Corporation Vacuum pump and semiconductor manufacturing apparatus
US7645126B2 (en) 2003-07-10 2010-01-12 Ebara Corporation Vacuum pump and semiconductor manufacturing apparatus
US7762763B2 (en) * 2003-09-30 2010-07-27 Edwards Limited Vacuum pump
US20070020116A1 (en) * 2003-09-30 2007-01-25 Ikegami Mold Engineering Co., Ltd Vacuum pump
US20070274822A1 (en) * 2003-12-23 2007-11-29 Liu Michael C K Vacuum Pump
FR2869369A1 (fr) * 2004-04-21 2005-10-28 Alcatel Sa Pompe a vide multi-etagee, et installation de pompage comprenant une telle pompe
US7670119B2 (en) 2004-04-21 2010-03-02 Alcatel Multistage vacuum pump and a pumping installation including such a pump
EP1589227A1 (fr) * 2004-04-21 2005-10-26 Alcatel Pompe à vide multi-étagée et installation de pompage comprenant une telle pompe
US20060291997A1 (en) * 2004-10-26 2006-12-28 Wilson Erich A Fluid Flow Chambers and Bridges in Bladeless Compressors, Turbines and Pumps
US20060216149A1 (en) * 2004-10-26 2006-09-28 Wilson Erich A Fluid Flow Channels in Bladeless Compressors, Turbines and Pumps
US20070092369A1 (en) * 2005-10-25 2007-04-26 Erich Wilson Bracket/Spacer Optimization in Bladeless Turbines, Compressors and Pumps
US7478990B2 (en) 2005-10-25 2009-01-20 Wilson Erich A Bracket/spacer optimization in bladeless turbines, compressors and pumps

Also Published As

Publication number Publication date
GB1291353A (en) 1972-10-04
DE1950328B2 (de) 1976-09-23
NL7010108A (enrdf_load_stackoverflow) 1971-04-01
JPS4814626B1 (enrdf_load_stackoverflow) 1973-05-09
DE1950328A1 (de) 1971-04-01

Similar Documents

Publication Publication Date Title
US3668393A (en) Apparatus having evacuation spaces and a pumping assembly
US3144035A (en) High vacuum system
US6872956B2 (en) Particle beam device with a particle source to be operated in high vacuum and cascade-type pump arrangement for such a particle beam device
US11434913B2 (en) Multiple port vacuum pump system
US5788825A (en) Vacuum pumping system for a sputtering device
US4383178A (en) System for driving rotary member in vacuum
US5228838A (en) Method for the evacuation of a low-vacuum chamber and of a HGH-vacuum chamber, as well as a high-vacuum apparatus for the practice thereof
US3633027A (en) Mass spectrometer connected to a gap chromatograph through a valved molecule separator
EP0119451B2 (en) Multiport cryopump
US5114316A (en) Method of regenerating a vacuum pumping device
CA2462934A1 (en) Multi-chamber installation for treating objects under vacuum, method for evacuating said installation and evacuation system therefor
US5247133A (en) High-vacuum substrate enclosure
US9336990B2 (en) Semiconductor process pumping arrangements
EP3867528B1 (en) Non-mechanical vacuum pumping system and analytical instrument
US4149084A (en) Apparatus for maintaining ion bombardment beam under improved vacuum condition
JP5342367B2 (ja) 真空排気装置および真空排気装置の使用方法
WO2020208375A1 (en) Vacuum chamber module
JP7396237B2 (ja) 質量分析装置
US4081222A (en) Combined vacuum baffle and valve for diffusion pump
JPH0429402Y2 (enrdf_load_stackoverflow)
GB2578293A (en) A set of pumps, and a method and system for evacuating a vacuum chamber in a radioactive environment
JP2000205418A (ja) 磁性流体封止型回転導入機
KR200324096Y1 (ko) 이온펌프의 고전압 피드쓰루 장착용 함몰형 유입구 구조
US3515171A (en) Side pumped vacuum collar
JPH1140094A (ja) 真空装置の排気システムおよび排気方法