EP0281654B1 - Machine à deux arbres - Google Patents

Machine à deux arbres Download PDF

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Publication number
EP0281654B1
EP0281654B1 EP87103508A EP87103508A EP0281654B1 EP 0281654 B1 EP0281654 B1 EP 0281654B1 EP 87103508 A EP87103508 A EP 87103508A EP 87103508 A EP87103508 A EP 87103508A EP 0281654 B1 EP0281654 B1 EP 0281654B1
Authority
EP
European Patent Office
Prior art keywords
pistons
housing
layer
machine
coating
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
EP87103508A
Other languages
German (de)
English (en)
Other versions
EP0281654A1 (fr
Inventor
Josef Heppekausen
Hans-Peter Dr. Kabelitz
Karl-Heinz Ronthaler
Ralf Steffens
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.)
Balzers und Leybold Deutschland Holding AG
Original Assignee
Leybold AG
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
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=8196822&utm_source=***_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0281654(B1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Leybold AG filed Critical Leybold AG
Priority to DE8787103508T priority Critical patent/DE3769468D1/de
Priority to EP87103508A priority patent/EP0281654B1/fr
Priority to JP63042422A priority patent/JPS63230902A/ja
Publication of EP0281654A1 publication Critical patent/EP0281654A1/fr
Priority to US07/458,384 priority patent/US4974318A/en
Application granted granted Critical
Publication of EP0281654B1 publication Critical patent/EP0281654B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01C—ROTARY-PISTON OR OSCILLATING-PISTON MACHINES OR ENGINES
    • F01C1/00—Rotary-piston machines or engines
    • F01C1/08—Rotary-piston machines or engines of intermeshing engagement type, i.e. with engagement of co- operating members similar to that of toothed gearing
    • F01C1/082—Details specially related to intermeshing engagement type machines or engines
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01C—ROTARY-PISTON OR OSCILLATING-PISTON MACHINES OR ENGINES
    • F01C1/00—Rotary-piston machines or engines
    • F01C1/08—Rotary-piston machines or engines of intermeshing engagement type, i.e. with engagement of co- operating members similar to that of toothed gearing
    • F01C1/12—Rotary-piston machines or engines of intermeshing engagement type, i.e. with engagement of co- operating members similar to that of toothed gearing of other than internal-axis type
    • F01C1/126—Rotary-piston machines or engines of intermeshing engagement type, i.e. with engagement of co- operating members similar to that of toothed gearing of other than internal-axis type with elements extending radially from the rotor body not necessarily cooperating with corresponding recesses in the other rotor, e.g. lobes, Roots type
    • 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
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49229—Prime mover or fluid pump making
    • Y10T29/49236—Fluid pump or compressor making
    • 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
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49229—Prime mover or fluid pump making
    • Y10T29/49236—Fluid pump or compressor making
    • Y10T29/49242—Screw or gear type, e.g., Moineau type
    • 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
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49826—Assembling or joining
    • Y10T29/4984—Retaining clearance for motion between assembled parts

Definitions

  • the invention relates to a twin-shaft displacement machine for use in a vacuum with a housing and two shafts running parallel to one another, which carry pistons which are arranged in a scooping space formed by the housing such that they can be moved without contact with one another and relative to the scooping space. wherein the pistons or the pistons and the wall of the scoop are provided with a layer.
  • a machine of this type is known from US-A-29 44 732.
  • the pistons are coated with a layer that is as smooth as possible to increase the pumping capacity. No particular importance is attached to the play of the pistons with respect to one another and to the wall of the suction chamber.
  • DE-C-942 229 it is known to manufacture the rotary pistons of Roots blowers from an extruded profile material and to make them dimensionally stable by means of a coating.
  • twin-shaft machines of this type is therefore defined by the ratio of the amount of gas effectively pumped to the theoretically pumpable amount of gas.
  • the selection of any small games is not possible due to thermal reasons. During operation, the machine heats up and there is thus a reduction in the existing play, so that there is a risk of the pistons starting up on the housing.
  • the housing there is the possibility of dissipating the heat by water or air cooling.
  • the heat from the rotating pistons is essentially dissipated only by the medium itself, which either transfers the heat of the piston to the housing or removes it itself. Since only a few molecules are available to dissipate the heat when the twin-shaft machine is operated in a vacuum, the thermal problems in this pressure range are particularly critical. Since the degree of heating depends on the pressure difference between the outlet and inlet of the machine and a maximum temperature difference between the piston and the housing must not be exceeded in order to avoid contact when the game is being consumed, certain pressure differences must be observed when operating the twin-shaft machines. When using Roots pumps in a vacuum, for example, the difference between outlet pressure and inlet pressure must not exceed a specified permissible value, unless special piston cooling measures have been taken.
  • Two-shaft machines for use in the overpressure area differ, for example, from machines for use in a vacuum with essentially the same piston profile only in the cold play of the rotors to one another and radially and axially to the housing.
  • a Roots blower with a pumping speed of 1000 m3 / h, intended for use in the overpressure area is approx. 50 u, has a root pump with the same pumping speed, intended for use in a vacuum, a cold play that is about 4 times greater.
  • different pistons must therefore be manufactured depending on the area of pressure, so that the overall manufacturing effort is high.
  • the present invention has for its object to provide a twin-shaft machine of the type mentioned and a method for its manufacture.
  • the coating is intended to serve both to adapt the machine to the respective pressure range and to protect against corrosion and / or to influence the conveyed medium.
  • this object is achieved in a twin-shaft machine of the type mentioned at the outset in that the coating of the steel pistons comprises two partial layers, of which the lower layer consists of nickel and the upper layer consists of copper.
  • the manufacture of the pistons and the housing of the twin-shaft machine is expediently carried out in such a way that the pistons and the inner walls of the scooping chamber are first machined in a manner known per se by chip removal in such a way that the cold play of the parts is greater than that for all pressure ranges which the machine is used, would be required, and that after that the Adaptation of the game of the machine to the desired pressure range can be achieved by the coatings on the pistons and, if appropriate, also on the housing.
  • the proposed coatings should initially ensure that the cold play assumes a certain value. To do this, it is sufficient if only the pistons are provided with a double layer of such a thickness that the desired cold play is present. If additional protection of the pistons and also the inner walls of the scooping chamber against corrosion with the conveying medium or additives contained therein is to be achieved, then it is necessary to coat both the pistons and the inner walls of the scooping chamber and to choose the selected layer thicknesses such that desired cold play is reached.
  • the outer copper layer protects the piston and the scoop from corrosion.
  • the advantage of the invention is first of all that a large number of pistons and housings with uniform dimensions can be produced for the most varied application pressure ranges of a twin-shaft machine of a certain type. Individual layers can initially be adapted to their respective pressure application area by means of galvanically or chemically layers which are relatively true to contour. So far, the cold play selected was a compromise that enabled the machines to be used in the various pressure ranges of the vacuum (rough vacuum, fine vacuum, etc.).
  • the invention makes it possible in a particularly simple manner to select the cold play of two-shaft machines, in particular Roots pumps, in such a way that they are matched to the respective pressure application, that is to say that their volumetric efficiency is optimal for the respective pressure range.
  • Roots vacuum pumps are particularly suitable, for example, for use in circulating systems for CO2 lasers.
  • With the generation of laser light is one Dissociation of CO 2 in CO and O2 connected.
  • a catalytic effect occurs which reverses the dissociation mentioned.
  • the CO2 gas mixture flowing around in the gas laser therefore has a longer service life. A gas exchange is required less frequently, so that the operating costs of the gas laser can be significantly reduced.
  • the housing of the Roots pump 1 shown in FIGS. 1 to 3 is designated by 2.
  • Your scoop space 3 is formed by the inner walls of the housing 2 and the side plates 4, 5 (Fig. 3).
  • the 8-shaped pistons 6 and 7 are rotatably arranged in a contact-free manner within the scoop space.
  • the weles 8 and 9 are stored in the side plates 4 and 5.
  • the movement of the pistons 6 and 7 is synchronized by means of the toothed wheels 11 and 12, which are fastened to the stumps of the shafts 8, 9 passing through the end shield 4.
  • the opposite side of the Roots pump on the wheel side is referred to as the drive side.
  • One of the dies on this page is coupled to a drive motor, not shown.
  • the pistons 6 and 7 rotate in the direction of the arrows 13, as a result of which the conveying direction (arrows 14) is determined.
  • the inlet and outlet of the pump are designated 15 and 16, respectively.
  • the pistons 6, 7, the inner sides of the end shields 4, 5 and the inner walls of the housing 2 are first machined in such a way that the cat games A to F are larger than is required for all areas of application, for which this machine comes into question is required. Thereafter, the originally too large cold clearances are reduced by a desired amount by means of targeted, true-to-contour coatings, so that only different coatings of this type of piston pumps can be produced for different areas of application. If the Roots pump is at risk of corrosion due to the pumped media, for example, then all pump-active surfaces must be coated. Just the cold game to a certain extent brought, then it is sufficient if the pistons 6 and 7 are provided with targeted coating thicknesses.
  • the parts to be coated usually consist of steel.
  • a preferred layer material is nickel.
  • Nickel layers can be applied true to the contours by coating with electroless nickel with reproducible layer thicknesses. If the parts are to be Cu-coated, it is advisable to first apply a nickel layer as the basis and then the Cu layer.
  • the thickness of the two layers should be chosen so that the cold play corresponding to the area of application is achieved. It has proven to be advantageous if the copper layer thickness is 25 ⁇ and the thickness of the nickel layer is chosen according to the desired cold play.
  • Figures 4 to 6 show schematically how the layers can be applied.
  • the tub of an electroplating bath is designated, in which the parts to be coated are immersed and connected as a cathode.
  • An anode 22 is assigned to the side to be coated, the shape of which is adapted to the contour of the surface to be coated.
  • a flat anode 22 is therefore assigned to the end shield shown in FIG. 4.
  • the anodes are each approximately 8-shaped as an example.
  • the anode 22 serving to coat the piston 6 or 7 has the shape of a basket and surrounds the piston equidistantly when a uniform layer is to be applied.
  • Flat anode sections are also assigned to the end faces of the piston if a coating of the end faces is to be achieved.
  • the thickness of the applied layer can be influenced by locally changing the distance between the piston and the anode.
  • an 8-shaped basket anode 22 is also provided, which is also arranged essentially equidistant within the scooping space 3. Additional anodes, not shown, can also be used to coat the inside of the connecting pieces of inlet 15 and outlet 16.
  • the anodes 22 can be sacrificial anodes. However, anodes that consist of expanded titanium and have a basket-shaped design have proven to be particularly advantageous, since they enable a contour-conforming adjustment.
  • the desired coating material is preferably in the anode basket as clippings.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Applications Or Details Of Rotary Compressors (AREA)

Claims (2)

  1. Machine de déplacement à deux arbres (1) destinée à être utilisée dans le domaine du vide, comprenant un corps (2) et deux arbres (8, 9) qui s'étendent parallèlement l'un à l'autre, et portent des pistons (6, 7) qui sont disposés dans une chambre d'aspiration (3) formée par le corps (2) de manière à pouvoir se déplacer sans contact entre eux ni avec la chambre d'aspiration, les pistons (6, 7) seuls ou les pistons (6, 7) et la paroi de la chambre d'aspiration (3) étant revêtus d'une couche, caractérisée en ce que le revêtement des pistons (6, 7) en acier comprend deux couches partielles dont la couche inférieure est composée de nickel et la couche supérieure de cuivre.
  2. Machine selon la revendication 1, caractérisée en ce que l'épaisseur de la couche supérieure, en cuivre, est d'environ 25 µ et que la couche inférieure, en nickel, est choisie d'une épaisseur telle que les éléments présentent le jeu à froid nécessaire pour le domaine de pression d'utilisation envisagé.
EP87103508A 1987-03-11 1987-03-11 Machine à deux arbres Expired - Lifetime EP0281654B1 (fr)

Priority Applications (4)

Application Number Priority Date Filing Date Title
DE8787103508T DE3769468D1 (de) 1987-03-11 1987-03-11 Zweiwellenmaschine.
EP87103508A EP0281654B1 (fr) 1987-03-11 1987-03-11 Machine à deux arbres
JP63042422A JPS63230902A (ja) 1987-03-11 1988-02-26 二軸機械
US07/458,384 US4974318A (en) 1987-03-11 1989-12-28 Method of making a dual-shaft machine

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP87103508A EP0281654B1 (fr) 1987-03-11 1987-03-11 Machine à deux arbres

Publications (2)

Publication Number Publication Date
EP0281654A1 EP0281654A1 (fr) 1988-09-14
EP0281654B1 true EP0281654B1 (fr) 1991-04-17

Family

ID=8196822

Family Applications (1)

Application Number Title Priority Date Filing Date
EP87103508A Expired - Lifetime EP0281654B1 (fr) 1987-03-11 1987-03-11 Machine à deux arbres

Country Status (4)

Country Link
US (1) US4974318A (fr)
EP (1) EP0281654B1 (fr)
JP (1) JPS63230902A (fr)
DE (1) DE3769468D1 (fr)

Families Citing this family (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0292087U (fr) * 1989-01-10 1990-07-20
JPH03290086A (ja) * 1990-04-06 1991-12-19 Hitachi Ltd スクリュ式回転機械と該機械のロータ表面処理方法およびドライ方式のスクリュ式回転機械と該機械のロータ表面処理方法
AT397134B (de) * 1991-02-19 1994-02-25 Hoerbiger Ventilwerke Ag Ventil
DE4300274A1 (de) * 1993-01-08 1994-07-14 Leybold Ag Vakuumpumpe mit Rotor
JP3350276B2 (ja) * 1994-12-28 2002-11-25 東芝キヤリア株式会社 ロータリコンプレッサ
US6092283A (en) * 1995-10-18 2000-07-25 Caterpillar Inc. Method and apparatus for producing a gear pump
US5797181A (en) * 1996-11-18 1998-08-25 Siemens Automotive Corporation Methods of manufacturing automotive fuel pumps with set clearance for the pumping chamber
JPH10220371A (ja) 1997-02-07 1998-08-18 Tochigi Fuji Ind Co Ltd 流体機械
JPH10266982A (ja) * 1997-03-21 1998-10-06 Tochigi Fuji Ind Co Ltd ルーツ式流体機械
US5993183A (en) * 1997-09-11 1999-11-30 Hale Fire Pump Co. Gear coatings for rotary gear pumps
EP0975874A1 (fr) * 1998-02-13 2000-02-02 Ebara Corporation Rotor de pompe a vide et procede de fabrication associe
JP2003343469A (ja) * 2002-03-20 2003-12-03 Toyota Industries Corp 真空ポンプ
US7553143B2 (en) * 2004-04-19 2009-06-30 The Regents Of The University Of California Lobe pump system and method of manufacture
GB0519402D0 (en) * 2005-09-23 2005-11-02 Tonery David Air intake system
US20070164087A1 (en) * 2006-01-17 2007-07-19 Honeywell International, Inc. Method for repair of housings

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DE437757C (de) * 1923-04-30 1926-11-26 Karl Werner Dipl Ing Abdichtung fuer Schraubendrehkolbenmaschinen
US2754050A (en) * 1950-04-22 1956-07-10 Gen Motors Corp Rotary blower
DE924229C (de) * 1953-01-29 1955-02-28 Hannoversche Maschb Aktien Ges Verfahren zur Herstellung der Drehkolben von Rootsgeblaesen
US2944732A (en) * 1955-02-24 1960-07-12 Heraeus Gmbh W C Vacuum pumps
GB772350A (en) * 1955-09-13 1957-04-10 Hanomag Ag A method and a device to improve the volumetric efficiency of root's blowers
GB1269205A (en) * 1968-05-30 1972-04-06 Lucas Industries Ltd Gear pumps
US3680990A (en) * 1971-04-30 1972-08-01 Sperry Rand Corp Removable liner for gear pump
JPS5675992A (en) * 1979-11-21 1981-06-23 Hitachi Ltd Rotor for screw compressor
DD155102A1 (de) * 1980-12-05 1982-05-12 Dieter Prockat Beschichtete rotoren fuer rotationskolbenverdichter
JPS58148292A (ja) * 1982-02-26 1983-09-03 Hitachi Ltd スクリユ−圧縮機のロ−タ表面処理
FR2530742B1 (fr) * 1982-07-22 1987-06-26 Dba Compresseur volumetrique a vis
JPS59196989A (ja) * 1983-04-23 1984-11-08 Anretsuto:Kk ル−ツブロワ−
JPS6056190A (ja) * 1983-09-08 1985-04-01 Taiho Kogyo Co Ltd ル−ツブロワ
JPS6056191A (ja) * 1983-09-08 1985-04-01 Taiho Kogyo Co Ltd ル−ツブロワ
JPS60230587A (ja) * 1984-04-27 1985-11-16 Toyota Motor Corp ル−ツ式流体送給機用まゆ形ロ−タの製造方法
JPS61197788A (ja) * 1985-02-27 1986-09-02 Hitachi Ltd 無給油式スクリユ−圧縮機
US4695233A (en) * 1986-07-10 1987-09-22 Kabushiki Kaisha Kobe Seiko Sho Screw rotor mechanism

Also Published As

Publication number Publication date
EP0281654A1 (fr) 1988-09-14
JPS63230902A (ja) 1988-09-27
US4974318A (en) 1990-12-04
DE3769468D1 (de) 1991-05-23

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