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EP0080585A1 - Compresseur à pistons rotatifs - Google Patents

Compresseur à pistons rotatifs Download PDF

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Publication number
EP0080585A1
EP0080585A1 EP82109275A EP82109275A EP0080585A1 EP 0080585 A1 EP0080585 A1 EP 0080585A1 EP 82109275 A EP82109275 A EP 82109275A EP 82109275 A EP82109275 A EP 82109275A EP 0080585 A1 EP0080585 A1 EP 0080585A1
Authority
EP
European Patent Office
Prior art keywords
rotor
screw
line
main rotor
main
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.)
Granted
Application number
EP82109275A
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German (de)
English (en)
Other versions
EP0080585B1 (fr
Inventor
Beteiligungsgesellsch Technika
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.)
Individual
Original Assignee
Individual
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Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to AT82109275T priority Critical patent/ATE14779T1/de
Publication of EP0080585A1 publication Critical patent/EP0080585A1/fr
Application granted granted Critical
Publication of EP0080585B1 publication Critical patent/EP0080585B1/fr
Expired legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
    • F04C18/08—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
    • F04C18/082—Details specially related to intermeshing engagement type pumps
    • F04C18/084—Toothed wheels
    • 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
    • Y10T74/00—Machine element or mechanism
    • Y10T74/19—Gearing
    • Y10T74/19949—Teeth
    • Y10T74/19953—Worm and helical

Definitions

  • the invention relates to a parallel and outer-axis rotary compressor with at least one helically toothed main rotor and in each case a secondary rotor meshing therewith.
  • Such a rotary compressor is e.g. become known from DE-OS? 5o5 113.
  • the laid-open specification deals in particular with the formation of the tooth flanks of the secondary rotor, around the blow hole of the compressor toothing which is present in rotary piston compressors, which arises from the fact that the contact line along which the tooth flanks of one tooth of the main and secondary rotor of an engaged pair of teeth lie against one another, not as far as the edge of the housing, which is the intersection of the two housing bores, (see also Rinder, Springer-Verlag Vienna, New York 1979, p. 72 ff), should be kept as small as possible.
  • the rotors of screw compressors - in order to keep leakages as small as possible - must be manufactured with the greatest precision, which requires complex and expensive tools and machine tools. Due to the complicated design of the individual profiles, separate milling cutters are required, whereby the manufacture of a rotor usually involves several work steps (pre-milling with so-called roughing cutters and then finishing with finishing or fine milling cutters). A cutter set for a pair of rotors costs between DM 20,000 and 50,000 depending on the diameter. In addition, there is the effort for the necessary final checks.
  • Rotary lobe compressors with different delivery volumes are commercially available in order to meet the respective desired requirements. Accordingly, the manufacturers offer compressor series in which the distance between the stages is chosen to be relatively large because of the expensive manufacture, so that too many expensive tools do not have to be manufactured and kept in stock. The result of this is that the individual types of rotary compressor are not operated directly in their optimal range or in the vicinity of the optimum range, but rather over a larger range.
  • 1 shows the specific power consumption in (kW / m 3 / min) over the delivery volume (m 3 / min).
  • the circumferential speed of a rotor or its speed could also be plotted on the abscissa; the qualitative statement would not change here. As can be seen from FIG.
  • the optimum operating point lies at the specific power requirement minimum, i.e. at point A of the curve shown.
  • the rotary lobe compressors currently on the market run in the BAC range, i.e. not exclusively in or close to the optimal range, which would be around B 'AC', in order to have the flow volume flow of one type connected as seamlessly as possible to that of the next larger type.
  • the expansion of the flow rate range for each type must be achieved by changing the speed by means of a transmission gear (belt or gear drive or by means of speed control of the drive motor).
  • the object of the invention is to provide a rotary compressor of the type mentioned, which is simple to manufacture is and in which relatively inexpensive tools for producing the profiles are required.
  • the dimensional control should also be able to be carried out precisely, inexpensively and simply.
  • the tooth flanks of the main rotor are oblique open jet screw surfaces, which are formed by screwing each of a straight line crossing the screw axis generating straight line, the inclination angle of the generating straight line to a plane perpendicular to the screw axis in its absolute value is smaller than the angle of inclination of the targets of the fillet screw line to this plane and the rise of the generating straight line and the rise of the tangent to the fillet screw line have opposite signs.
  • a further embodiment of the invention can be such that the tooth flanks of the secondary rotor are generated and determined against one another by the relative path of a point lying on a head line (main rotor head point) when the main and secondary rotors roll.
  • the main rotor advantageously has at least three teeth.
  • the tooth flanks of the main and secondary rotors are not composed of curve segments, but are formed by a steady, uniform, analytically definable curve shape from head point to head point because of the generating straight lines.
  • the tooth flanks of the main rotor are in the form of oblique, open jet screw surfaces (see Wunderlich, Representative Geometry, Volume 2, the series BI University Pocket Books, Volume 133, 1967, page 176 ff., And in particular page 183, point 97d).
  • the generatrix of the main rotor is therefore a straight line, the flanks in the frontal section being formed by the symmetrical part of an intricate circular involute.
  • the main rotor can be produced once by means of a hob cutter in a hobbing process. Since such a milling cutter the If the beam screwing surface is not exactly along the generating straight line, but touches along a space curve, the profile shape of a suitable cylindrical milling cutter is not exactly a straight line, but a curved line (profile milling cutter).
  • the flank can be produced by means of planing, in particular by means of planing or shaping. Such methods are common and common in transmission engineering; they are more precise than a hobbing process, but are more time-consuming.
  • the manufacture of the main rotor is significantly cheaper and the final inspection of the main rotor is also simplified, the simplification in particular being that the main rotor can be quasi two-dimensionally driven by means of a simple measuring device. Due to the simplified measuring device or the simplified measuring method for the final inspection, the tolerance band for the main rotor can also be significantly reduced.
  • the tooth flanks of the secondary rotor are formed by a wheel curve, which can be produced with a profile cutter with an arc-like shape.
  • a rotary lobe compressor series can be offered with significantly more refined gradation compared to known compressor series. It is possible to optimize the efficiency of the individual rotary lobe compressors in the series by choosing the optimum circumferential speeds in the absence of gears (gears and pinions or belts, adapted to the standard electrical speed of the drive, which is designed as an electric motor, for example).
  • the individual rotary compressor can be operated in direct drive in the area B A C '(Fig. 1), so that the optimal working area can be used.
  • the geometry of the manufactured rotor is also much easier to measure, which, as mentioned above, makes the final inspection can be cheaper.
  • the individual rotary piston compressor of such a series can be driven directly without intermediate transmission, so that an improvement in efficiency can be achieved in this way alone.
  • a further advantage of the configuration according to the invention also consists in the following: in known rotors, the tooth depth, ie the groove depth between two adjacent head lines, is large. As a result, the ratio of core diameter to outer diameter is also large. In known rotors, this value is between 0.4 to 0.5. In the rotor according to the invention, however, which is defined by the features of the characterizing part of claim 1, the ratio of core diameter to outer diameter is approximately 0.95.
  • the deflections to be expected in the main rotor according to the invention are therefore practically zero in comparison to the known main rotors. As a result, the tolerances can be kept very small and the individual main rotor is also very robust. Due to these tolerances, the efficiency can be further improved.
  • the rotary piston compressor which is generally designated 10, has a compression chamber 14 in a housing 12, in which a main rotor 16 and a secondary rotor 18 meshing therewith are arranged.
  • the main rotor 16 has at one end an extension 24 divided into two areas 2o and 22 with different diameters, one area 2o with a larger diameter of the bearing by means of roller bearings 26 and the other area 22 with a smaller diameter is used for connecting a drive (not shown) .
  • the bearing 26 is located in a l.agerausEnglishung 28 in a bearing disk 3 0, which is fixedly connected to the housing 12 together with an end cover 32 via a screw 34th
  • a sealing ring 36 is provided to seal the bearing 26 to the outside.
  • the main rotor 16 has a further bearing journal 38 which is mounted in a roller bearing 40 and in a ball bearing 42 in a first bearing opening 44 of the housing 12.
  • the holder of storage 4o and 42 is carried in via a nut screwed onto the bearing pin 38 nut 46 and the outside via a compression spring 48 which is supported on a second end cover 5 0, which is fixedly connected to the housing via bolts 52 with the interposition of a fixing sleeve 53 .
  • the secondary rotor 18 has a bearing journal 54 and 56 on the end face, of which the bearing journal 54 is supported in a roller bearing 58 in the bearing disk 30 and the bearing journal 56 in a roller bearing 60 and a ball bearing 62 in a second bearing opening 64 in the housing 12.
  • the mounting or axial fixation of the bearings 60 and 62 takes place on the inside diameter. on the inner ring of the bearings by means of a bearing 56 screwed nut and outside on the bearing outer ring via a compression spring 68 with the interposition of a fixing sleeve 70.
  • the reference number 72 denotes the throat line of the main rotor and the reference number 74 the dashed line of the secondary rotor.
  • the reference numbers 76 and 78 denote the top lines of the main and secondary rotors.
  • FIG. 3 shows a cross section along the line III-III of FIG. 1.
  • the main rotor 16 has a total of four teeth, the head points of which are represented in the section according to FIG. 3 by the reference numerals 8 0 , 82, 84 and 86.
  • the teeth are formed using an inclined, open jet screw surface.
  • the generatrix of this jet screw surface, which forms a screw, the circumferential curve between the head points 8o-82; 82-84; 84-86 and 86-8 0 is a circular involute, is a straight line G that runs obliquely to the screw axis S (see Fig. 8).
  • the angle of inclination ⁇ which the straight line G forms with a plane EE that is perpendicular to the screw axis, is absolute, i.e. in terms of its numerical value, smaller than the angle of inclination ⁇ of the fillet screw line of the profile in question, the increase in the straight line G having an opposite sign with respect to that of the rise of the throat screw line (see FIG. 8).
  • the secondary rotor 18 has nine teeth (which are not numbered in detail), wherein, as can be seen from FIGS. 4 to 7, the tooth flanks between the teeth are determined by the relative path of the head points 80 to 84 of the main rotor 16.
  • the secondary rotor tooth flanks in the case of pointed secondary rotor teeth are not circles but intertwined epitrochoids, which, however, can be approximately replaced by their circles of curvature during manufacture, that is, by arcs.
  • Fig. 4 shows a first position of Haunt and secondary rotor to each other, in which the head point 8 2 of the main rotor 16 in the position shown, ie . h . the head center line lies exactly on the connecting line VV of the central axes of the rotors.
  • the head point 82 is also aligned with the throat point 82 ′ of the secondary rotor 18, which likewise lies on the connecting line between the center points of the two rotors.
  • the center line of the head and the center of the throat coincide.
  • the head points 88 and 90 of the secondary rotor 1 8 lie exactly on the tooth flank of the tooth which has the head point 82.
  • the head point center line with the head point 82 moves clockwise, the head point 82 running exactly on the tooth flank of the secondary rotor in such a way that the tooth flank of the secondary rotor passes through the Path of the head point 82 is determined.
  • the head point 9o of the secondary rotor 1d is still on the other tooth flank.
  • the throat center line of the sewing rotor 18 has emigrated counterclockwise by a smaller amount counterclockwise from the connecting line between the center points of the two rotors, in accordance with the rotational speed ratio between the main rotor and the secondary rotor.
  • the head point 82 of the main rotor is located in the region of the head point 88 of the secondary rotor, the head point 90 still lying on the tooth flank of the main rotor. 7 that the head point 8? has come free from the secondary rotor, but the head point 9o still remains on the tooth flank.
  • the head point 84 comes into engagement with the secondary rotor, and the sequence or the geometry is the same as in FIGS. 4 to 7: the tooth flanks of the secondary rotor are determined by the respective knock point of the Main rotor formed, wherein when a head point of the main rotor is located between two head points of the secondary rotor, the two mentioned head points rest on the tooth flank or the tooth flanks of the main rotor.
  • the screw axis SS is shown schematically there, to which a plane EE runs perpendicularly.
  • the generating line is called GG.
  • the generating straight line GG forms an angle ⁇ with the plane EE, whereas the tangent 73 to the fillet screw line 72 at point P forms an angle ⁇ with the plane EE.
  • the angle ⁇ is absolute, ie in terms of its value, smaller than the angle ⁇ ; however, the inclinations of both angles have opposite signs.
  • the flank end intersection curve of the beam screwing surface generated by the straight line GG lies between two points P and P 2 and has the designation F (see FIG. 8, below), which can be derived from the generation as an involute. Due to the complexity of the calculation method, the tip circle radius u K and the angle ⁇ K to which each head point is assigned in each cross section must be determined numerically by iteration, whereby an explicit, closed representation is practically impossible.
  • tooth flanks of the secondary rotor are formed by the head point of the main rotor in the case of pointed secondary rotor teeth, an explicit calculation of the tooth flanks of the secondary rotor, which is to be regarded as a convoluted impeller line, is possible by calculation with electronic data processing.
  • the blow hole can be made practically zero. This is a further, particular advantage of the configuration according to the invention and for this reason the profile shape is also particularly advantageously suitable for small delivery volumes where even the smallest of leaks can lead to a significant reduction in efficiency.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Applications Or Details Of Rotary Compressors (AREA)
  • Rotary-Type Compressors (AREA)
EP82109275A 1981-10-09 1982-10-07 Compresseur à pistons rotatifs Expired EP0080585B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT82109275T ATE14779T1 (de) 1981-10-09 1982-10-07 Drehkolbenverdichter.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19813140107 DE3140107A1 (de) 1981-10-09 1981-10-09 Drehkolbenverdichter
DE3140107 1981-10-09

Publications (2)

Publication Number Publication Date
EP0080585A1 true EP0080585A1 (fr) 1983-06-08
EP0080585B1 EP0080585B1 (fr) 1985-08-07

Family

ID=6143717

Family Applications (1)

Application Number Title Priority Date Filing Date
EP82109275A Expired EP0080585B1 (fr) 1981-10-09 1982-10-07 Compresseur à pistons rotatifs

Country Status (5)

Country Link
US (1) US4662832A (fr)
EP (1) EP0080585B1 (fr)
JP (1) JPS58135395A (fr)
AT (1) ATE14779T1 (fr)
DE (1) DE3140107A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2609310A1 (fr) * 1987-01-06 1988-07-08 Baudot Hardoll Sa Profils de rotors, du type a vis, pour machines tournantes vehiculant un fluide gazeux

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE8434596U1 (de) * 1983-12-14 1985-02-21 Boge Kompressoren Otto Boge Gmbh & Co Kg, 4800 Bielefeld Drehkolbenverdichter
JP7229720B2 (ja) * 2018-10-26 2023-02-28 株式会社日立産機システム スクリュー圧縮機

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT169479B (de) * 1946-07-18 1951-11-26 Ljungstroems Angturbin Ab Drehkolbenmaschine
CH384768A (de) * 1959-09-02 1965-02-26 Ingersoll Rand Co Strömungsmittelpumpe oder -motor
DE2360403A1 (de) * 1973-12-04 1975-06-05 H & H Licensing Corp Schraubenkompressoranlage zum verdichten von gasfoermigen medien, insbesondere fuer geringe ansaugvolumina
DE2505113A1 (de) * 1974-06-24 1976-01-15 Atlas Copco Ab Parallel- und aussenachsige drehkolbenmaschine mit schraegverzahntem kaemmeingriff

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB254986A (en) * 1925-10-06 1926-07-15 Alexander Johan Mollinger Improvements in or relating to screw pumps
GB1197432A (en) * 1966-07-29 1970-07-01 Svenska Rotor Maskiner Ab Improvements in and relating to Rotary Positive Displacement Machines of the Intermeshing Screw Type and Rotors therefor

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT169479B (de) * 1946-07-18 1951-11-26 Ljungstroems Angturbin Ab Drehkolbenmaschine
CH384768A (de) * 1959-09-02 1965-02-26 Ingersoll Rand Co Strömungsmittelpumpe oder -motor
DE2360403A1 (de) * 1973-12-04 1975-06-05 H & H Licensing Corp Schraubenkompressoranlage zum verdichten von gasfoermigen medien, insbesondere fuer geringe ansaugvolumina
DE2505113A1 (de) * 1974-06-24 1976-01-15 Atlas Copco Ab Parallel- und aussenachsige drehkolbenmaschine mit schraegverzahntem kaemmeingriff

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2609310A1 (fr) * 1987-01-06 1988-07-08 Baudot Hardoll Sa Profils de rotors, du type a vis, pour machines tournantes vehiculant un fluide gazeux
WO1988005118A1 (fr) * 1987-01-06 1988-07-14 Baudot-Hardoll S.A. Profils de rotors, du type a vis, pour machines tournantes vehiculant un fluide gazeux
US5002472A (en) * 1987-01-06 1991-03-26 Societe Anonyme: Baudot-Hardoll S.A. Profiles of screw-type rotors for rotary machines conveying a gaseous fluid

Also Published As

Publication number Publication date
ATE14779T1 (de) 1985-08-15
US4662832A (en) 1987-05-05
DE3140107A1 (de) 1983-04-28
EP0080585B1 (fr) 1985-08-07
JPS58135395A (ja) 1983-08-11

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