Wolfgang Gaede ‐ Wegbereiter der Vakuumtechnik

The inventions of Wolfgang Gaede were the beginning of the extensive industrial application of vacuum technology: the 1905 invented high vacuum mercury pump simplified the production of electric bulbs. From this time Gaede joined the company E. Leybold's Nachfolger research & development activities for 40years. Three of his inventions, the diffusion pump, the (turbo‐) molecular pump and the principle of “gas ballast” are worldwide in use even today. The most important stations of Gaede's biography are reported.     

Der Gasballast

Wolfgang Gaedes last important invention: the Gasballast Gaedes invention of the rotating Mercury‐vacuumpump made highvacuum technology available for the industrial production. A second and third impact was given by gaedes molecular‐ and diffusionpump respectively, both depending on physikal effects firstly used for vacuum generation. Vacuum technology becomes increasing importance but the common oil sealed rotating pumps for fine vacuum suffer from contamination of the oil by vapor condensation. It was another invention from Gaede that eliminated this handycap in a very elegant way: the gasballast that is up to now a very important feature of this type of pumps.     

Der Beginn einer Erfolgsgeschichte

The beginnings of a successful story The exciting invention of the molecular Pump by Wolfgang Gaede was followed by his new ‘Device of Producing High Vacua’ in 1913. It was announced in the second edition 1913 of E.Leybold's cataloge. Three years later Langmuir in the USA presented a similar pump called ‘condensationpump’, but with clearly better pumping speed. Another design of a pump with two stages was invented by Prof. Volmer in Berlin. Other European companies announced similar pumps. Because Gaede claimed the prinziple of evacuating gas by diffusion, he and Leybold succeeded in making all of them to ask for licences. Respective to Langmuir they exchanged licence to each other. By the time this ‘diffusion pump’ was produced from metal instead of glas, and used special mineral oil, not mercury. In the middle of the 20.century it became a most important tool for creating high vacuum, available with a few liters per second to some thousend liters of pumping speed.     

100 Jahre HV‐Pumpe von Wolfgang Gaede. 100th Anniversary of Gaede's High Vacuum Pump

In 1905 Wolfgang Gaede invented a sturdy, quickly operating high vacuum pump, which was easy to use. It was produced and distributed under licence from E. LEYBOLD’s Nachf. This firstly allowed the application of high vacuum technique to industriel production. Gaede continued to work with Leybold just to the end of his life in 1945.     

Renaissance einer Hundertjährigen. Die Molekularpumpe von Wolfgang Gaede

New Success after 100 years: the ?Molecular Pump”? of Gaede The molecular drag pump was invented by W. Gaede in 1908. The design of the prototyp needed two years, and another two years later the first molecular pumps were 1912 ready for selling. But the sophisticated design and handling and the war 1914 limited the world wide application of the pump. Now at the end of the 20^th century the invention was successfully used as final compression stage in turbomolecular pumps.     

Geschichte der Vakuumtechnik. History of Vacuum Technology

The history of vacuum technology is more than 2000 years old. Over the past 400 years scientists, engineers and inventors such as Torricelli, Pascal, von Guericke and Gaede have been engaged in vacuum technology. Vacuum has become an essential instrument in science and technology and many processes could not exist without it. Furthermore vacuum technology has been developed as an individual industrially applied technology. The article describes the development of vacuum technology from ancient philosophical speculations about the mercurial glass pipe to the modern diffusion pump.     

65 Years of Turbopumps

Vacuum technology is not necessarily one of the sciences mentioned in connection with groundbreaking inventions. Nevertheless, it is a basic prerequisite for many developments and products that are taken for granted today. The influence of vacuum technology on our lives today can be traced back to the invention of the turbopump 65 years ago. Until then, the diffusion pump was considered the most widely used high and ultra-high vacuum pump, but with the help of Dr. Willi Becker's invention, it became possible to create hydrocarbon-free vacuum. It was only through a ‚clean' vacuum that many analyses and manufacturing processes became possible.     

Die patentierten Erfindungen von Wolfgang Gaede aus der Zeit von 1905 bis 1945

The Patented Inventions from Wolfgang Gaede from 1905 to 1945 The collection of Gaede's patents shows how successfully cooperation between science and industry could bee. Several up to now important inventions in vacuum technique have been made and this in sometimes hard and difficult circumstances. Even when Gaede has lost his chair at the university of Karlsruhe from illegal intrigues by the Nazis.     

Carl Hoffmann (1844 – 1910), der Erfinder der Drehschieberpumpe

Among the numerous constructions and designs of mechanical (vacuum) pumps around the turn of the 19th/20th century Hoffmanns invention of the sliding vane rotary vacuum pump may be considered as the real breakthrough in this field. His pump, manufactured since 1905 excels by the introduction of the – by now standard – back pressure valve which has been retained as an essential component in all later constructions of similar pumps, in particular of Gaede's so called “box” pump. The articel describes Hoffmann's professional life in context with the state of vacuum technology at his time.     

Abpumpverhalten von Roots‐ und Schraubenvakuumpumpen

Pump down characteristic of Roots pump combinations Combinations of roots pumps and screw type vacuum pumps are often used in industrial vacuum applications because of their high pumping capacity, their compact dimensions and their good energy efficiency. In load lock applications, the type of load control has a high influence on the evacuation time as well as on the energy efficiency of the pump combination. The operation limits of roots pumps are discussed and means to prevent an overload of the pump are introduced.     

Otto von Guericke und die Begründung der Lehre vom Luftdruck

The present paper is devoted to the quarter‐centenary celebration of Otto von Guericke, one of the prominent figures of the scientific revolution in the 17^th century. Guericke is well known for his invention of the air pump and his impressive demonstrations of the action of the atmospheric air pressure. Much less is known about Guerickes more theoretical achievements. In the present paper it is shown that Guericke also made, by some subtle vacuum experiments and their interpretation and the extension of the laws of hydrostatics of liquids to the air, important contributions to the basic principles of the physics of fluids.     

离心真空泵的气动设计探讨

高效率真空泵的设计技术对于工业的节能具有重要意义。根据某真空泵的设计要求,针对真空泵的工作叶轮的形式和设计点参数,分析和探讨了叶片负荷分布形式和分流叶片弦向和周向位置对性能的影响规律,在此基础上完成了该离心真空泵的气动设计。利用三维数值模拟软件对不同叶片扩压器角度情况下的性能曲线和内部流动进行计算。充分考虑真空泵内部流动的非对称性,采用了全通道计算,同时分析了真空泵的离心叶轮、叶片扩压器及蜗壳内部的流动特点。结果表明,叶片负荷分布形式和分流叶片弦向和周向位置对流量、出口气流角和效率均有较大的影响;通过改变叶片扩压器角度使得离心真空泵的特性线平移,使得离心真空泵在整个工作过程中始终工作在高效率区,达到节能的目的。     

镀膜设备真空系统主泵的配置

真空系统是真空镀膜设备的主要组成部分,其主泵的选择对真空性能影响很大,真空镀膜设备的发展要求真空性能清洁无油,动态抽速大.传统的以油扩散泵为主泵的设备不能满足要求,本文叙述了油扩散泵、分子泵及低温泵的特点及北京北仪创新真空技术有限责任公司开发以分子泵及低温泵为真空系统主泵的镀膜设备情况.     

GQZ—400新型高真空油增压泵

为使油增压泵在高真空领域有较高抽速，改进了现有油增压泵的结构，其极限真空和抽速有了显著提高。扩大了它的应用范围。在真空设备中得到了成功地应用。     

A novel route to compact,high performance pumping in UHV–XHV vacuum systems

The need to miniaturize and reduce the footprint of vacuum systems is increasing in industrial and research devices, such as portable analyzers, electron microscopes, surface science systems, semiconductor tools or particle accelerators. This poses serious challenges to the pumping groups in term of design, space constraints and weight. In this paper a novel type of combination pump is introduced, which integrates into a single device a Non Evaporable Getter (NEG) element with a small sputter ion pump (SIP). In this design, the NEG element acts as the main vacuum pump to remove hydrogen and the active gases, leaving to the SIP the ancillary task of pumping inert gases, which are not sorbed by the NEG. This approach, which develops large pumping speeds in a compact package, is helpful to achieve appropriate vacuum conditions in laboratory equipment. It can also improve and simplify the design of complex vacuum systems and apparatuses.     

Ti-Zr-V non-evaporable getter films: From development to large scale production for the Large Hadron Collider

Non-evaporable getter (NEG) alloys after dissolution of their native oxide layer into the bulk are able to pump most of the gases present in ultra-high vacuum systems. The dissolution process, commonly called activation, is obtained by heating in vacuum. NEG materials can be sputter-deposited as a thin film on the inner wall of a vacuum chamber, transforming it from a source of gas into an effective pump. The most significant advance in the development of NEG films was the discovery of a very low activation temperature (180 °C for 24 h heating) in a large range of compositions of the Ti-Zr-V system. This favourable property was correlated with nanometric grain size of the film (about 3 to 5 nm).In addition to pumping, NEG films lead to reduced induced gas desorption and secondary electron yields. As a consequence, Ti-Zr-V films provide the optimum solution to most of the problems encountered in vacuum systems of modern particle accelerators for high energy physics and for synchrotron radiation facilities. In the near future the most significant benchmark for Ti-Zr-V films will be the Large Hadron Collider (LHC) presently under construction at CERN, where about 6 km of beam pipe are being coated. A dedicated magnetron sputtering facility has been built to cope with the high number of vacuum chambers (about 1200) and the tight production schedule.     

粉碎式真空排污泵结构设计与性能分析

污水的真空收集技术在船舶、列车,建筑等领域有着广范的应用。而以真空粉碎泵为核心的泵站系统,则是真空排水技术中较为先进的一种方式。本文参照目前可靠性较高的Jets公司的真空粉碎泵专利,分析了粉碎式真空排污泵的设计难点,推导获得了关键零部件设计计算公式,并针对我公司的具体使用环境,对粉碎式真空排污泵的各零部件进行了设计计算,最终完成了样机的试制,并进行了试验检测。测试泵性能满足使用要求,但是与计算值仍有一定差距,需要进一步优化泵体设计。     

Applications of non evaporable getter pump in vacuum metrology

Applications of non evaporable getter pump in vacuum metrology are reviewed and discussed with a special focus on static expansion primary vacuum standard, and flow division method ultra-high vacuum (UHV) and extremely high vacuum (XHV) standard. The results obtained show that the non evaporable getter pump is suited for extending the calibration lower limit, and it is a valuable supplement to the basic methods. The feasibility of use of non evaporable getter pump in constant conductance method vacuum leak standard is also discussed.     

1.18 A versatile cryopump for industrial vacuum systems

The advantages of cryopumping, e.g. high pumping speed, flexibility, cleanliness and wide pressure range of operation, have long been recognised. Nevertheless, industrial application of this method has been rejected so far. This paper describes the vacuum performance of a cryopump equipped with a recently introduced cryogenerator. The machine offers a cold production of approximately 50 W at 80 K and 10 W at 20 K simultaneously, thus eliminating the need for a liquid helium and (or) nitrogen supply. Data presented show that industrial applications of cryopumping at 20 K impose special requirements on the design of the cryopanels and the cold capacity of the cryogenerator. It is shown that a 10 W cold capacity will offer long term operation of the pump, particularly in industrial thin film coaters, if (a) hydrogen gas is distributed uniformly over an adsorbent glued on a 20 K panel, (b) the grain size of the adsorbent is about one millimetre, and (c) contamination of the adsorbent by gases more easily condensable than hydrogen is avoided.     

非蒸散型吸气剂泵在真空计量中的应用研究

本文简要阐述了非蒸散型吸气剂(NEG)泵的吸气机理,着重介绍了NEG泵在超高/极高真空标准、静态膨胀法真空标准等真空计量标准中的最新应用结果。结果表明:利用NEG泵在室温下获得了10-10Pa的XHV;利用NEG泵将超高/极高真空标准校准下限延伸到了10-10Pa量级;利用NEG泵将静态膨胀法真空标准的校准下限延伸到了10-7Pa量级。最后还对用NEG泵延伸固定流导法微流量标准测量下限的可行性进行了分析。