EP0544105B1 - Compresseur à pistons économe en énergie - Google Patents

Compresseur à pistons économe en énergie Download PDF

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Publication number
EP0544105B1
EP0544105B1 EP92118157A EP92118157A EP0544105B1 EP 0544105 B1 EP0544105 B1 EP 0544105B1 EP 92118157 A EP92118157 A EP 92118157A EP 92118157 A EP92118157 A EP 92118157A EP 0544105 B1 EP0544105 B1 EP 0544105B1
Authority
EP
European Patent Office
Prior art keywords
suction valve
piston
lamella
type compressor
valve lamella
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
EP92118157A
Other languages
German (de)
English (en)
Other versions
EP0544105A1 (fr
Inventor
Dieter Spurny
Hans Unger
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.)
Knorr Bremse Systeme fuer Nutzfahrzeuge GmbH
Original Assignee
Knorr Bremse Systeme fuer Nutzfahrzeuge GmbH
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
Application filed by Knorr Bremse Systeme fuer Nutzfahrzeuge GmbH filed Critical Knorr Bremse Systeme fuer Nutzfahrzeuge GmbH
Publication of EP0544105A1 publication Critical patent/EP0544105A1/fr
Application granted granted Critical
Publication of EP0544105B1 publication Critical patent/EP0544105B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/16Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00 by adjusting the capacity of dead spaces of working chambers
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B39/00Component parts, details, or accessories, of pumps or pumping systems specially adapted for elastic fluids, not otherwise provided for in, or of interest apart from, groups F04B25/00 - F04B37/00
    • F04B39/10Adaptations or arrangements of distribution members
    • F04B39/1073Adaptations or arrangements of distribution members the members being reed valves
    • F04B39/1086Adaptations or arrangements of distribution members the members being reed valves flat annular reed valves
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/22Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00 by means of valves
    • F04B49/24Bypassing
    • F04B49/243Bypassing by keeping open the inlet valve

Definitions

  • the invention relates to an energy-saving piston compressor, in particular for the compressed air supply in motor vehicles, with a pressure-dependent switchable idle device for the suction valve provided with a suction valve lamella, the suction valve lamella being perpendicular to the cylinder axis of the cylinder of the piston compressor assigned to it and overlapping the suction valve openings of a valve plate and the Pressure valve openings in the valve plate releasing working position and in an idle position at least partially releasing the suction valve openings and at least partially covering the pressure valve openings can be moved in a straight line, and with a pneumatic piston drive for displacing the suction valve lamella against the force of a spring from the working position to the idling position.
  • Such a piston compressor is known from DE-OS-39 09 531.
  • the suction valve lamella is provided near its piston drive end with two oblong holes arranged in mirror image to a central plane, through which fixed guide bolts engage; As a result, the suction valve lamella experiences only a poor parallel guidance in its direction of displacement.
  • the piston drive is arranged offset to the suction valve lamella in the direction of the cylinder axis and has one to the cylinder axis and to the displacement direction of the suction valve lamella, the piston drive axis runs at right angles.
  • the piston of the piston drive which can be pressurized with compressed air on the one hand and is spring-loaded on the other hand, is coupled by means of a pin to a rotary lever which, in turn, can shift the suction valve lamella by means of a further pin.
  • the coupling of the rotary lever to the suction valve lamella is not in the median plane already mentioned, the suction valve lamella thereby experiences a one-sided drive, which can exert a torque to be absorbed by the suction lamella guide on the suction valve lamella.
  • the known piston compressor is thus structurally and kinematically complex with regard to the drive of its suction valve lamella.
  • suction valve lamella viewed in its direction of displacement, has guide surfaces running near its two ends parallel to the direction of displacement and to the cylinder axis, which have sliding surfaces in parallel with them on the valve plate or on parts firmly held on it, with parallel surfaces stand.
  • valve plate 1 which can be placed on the cylinder end of the piston compressor by means of a sealing washer 2, which has the outline 3 shown in dash-dotted lines in FIG. 1, and is to be held by means of screw bolts penetrating through the bores 4.
  • the bore of the cylinder corresponds to line 5
  • the cylinder axis 6 is perpendicular to the plane of the drawing.
  • the valve plate 1 is provided with a flat recess 7, the outline of which corresponds to line 8.
  • a suction valve lamella 9 In the recess 7 there is a suction valve lamella 9, which is approximately annular in a known manner. In its working position shown in the right part of FIG.
  • the suction valve lamella 9 overlaps the suction valve openings 11 in the valve plate 1 with its oscillating area 10, which is oscillatable at right angles to the plane of the drawing in FIG. 1; it lies in its idle state with resilient internal stress on the mouths of the suction valve openings 11.
  • the pressure valve openings 13 of the valve plate 1 openly open into the free, approximately circular interior 14 of the suction valve lamella 9 in their working position directly at the clamping area end of the interior 14.
  • the suction valve lamella 9 In its clamping area 12, the suction valve lamella 9 is displaceable at right angles to the cylinder axis 6, but cannot be lifted off the valve plate 1; in this area it can be in a flat space formed by the recess 7 between the valve plate 1 and the upper limit of the cylinder or engage the sealing washer 2.
  • the suction valve lamella 9 is in the recess 7 in the direction of a connecting line from its clamping area 12 to hers Vibration range 10 is displaceable, the displacement direction thus runs in the direction of a plane 15 containing the cylinder axis 6 and at right angles to the plane of the drawing.
  • the suction valve lamella 9 is arranged with two flaps that are mirror images of the center plane 15 and laterally offset, projecting parallel to the displacement direction 16 provided.
  • the side surfaces of the tabs 16 facing away from one another are formed to guide surfaces 17 which run parallel to the central plane 15, that is to say parallel to the direction of displacement and to the cylinder axis 6.
  • the guide surfaces 17 are in sliding engagement with corresponding counter surfaces 18, which form part of the outline according to line 8 of the recess 7.
  • the suction valve lamella 9 is provided with a broad, projecting tab, the side surfaces of which form parallel guide surfaces 17 'to the guide surfaces 17', which are also in sliding engagement with opposite surfaces 18 'on the side wall of the recess 7. Due to the guide surfaces 17, 17 'and their counter surfaces 18, 18', the suction valve lamella 9 experiences an exact and kinematically favorable sliding guide with a large guide length parallel to the central plane 15, so there is no risk of rotation and therefore jamming for the suction valve lamella 9.
  • the guide parts 22 each carry one in parallel to the cylinder axis 6 extending pin 24, which extend through an elongated hole-like opening 25 in the wall of the cylinder 19 and are connected at their end to the suction valve lamella 9.
  • a spring 26 is clamped between the stop-side end of the guide parts 22 and the bottom of the cylinders 19.
  • the pressure medium connections 21 are connected in a not shown, conventional manner to a control line, the pressurization of which can be switched by a pressure regulator, which in turn is switched by the pressure in an air container to be charged by the piston compressor, such that the pressure medium connections 21 are vented when the pressure drops below a lower pressure threshold in the air container , on the other hand, compressed air is applied when an upper pressure threshold is exceeded.
  • the pistons 20 and guide parts 22 are under the force of the springs 26 in their end position facing away from the cylinder axis 6, as shown in FIG. 1, right half.
  • the suction valve lamella 9 is in its end position on the piston drive side, which is the working position: by lifting the oscillating area 10 of the suction valve lamella 9 from the mouths of the suction valve openings 11, air can be sucked into the cylinder space of the piston compressor during the suction stroke and then during the compression stroke through the open pressure valve openings 13 compacted can be pushed out again.
  • the piston compressor works in the usual way.
  • the pistons 20 are moved against the force of the springs 26 in the direction of the cylinder axis 6 until the stops 23 are placed against the bottom of the respective cylinder 19, as shown on the left in FIG.
  • the suction valve lamella 9 is taken along via the pins 24, so it undergoes a linear displacement into its idle position, in which it at least partially releases the suction valve openings 11 at least partially and the pressure valve openings 13 at least partially, in the illustrated exemplary embodiment completely covers. Compressed air can practically no longer be conveyed by the piston compressor in this idling position; when its piston rises and falls, air is only sucked out of its suction chamber into the cylinder chamber.
  • the suction valve lamella 9 When the pressure medium connections 21 are subsequently vented, the suction valve lamella 9 returns to its working position under the force of the springs 26. As already mentioned, the suction valve lamella 9, via its guide surfaces 17, 17 'and the counter surfaces 18, 18', is given good guidance which prevents them from being tilted and tilted during the displacement movements.
  • the guide parts 22 can be formed in one piece or in one piece with the associated pistons 20, furthermore the two pressurization spaces for both pistons 20 can be connected to a common pressure medium connection 21 through an air guide channel running in the valve plate 1, the second pressure medium connection can omitted.
  • the greater height of the recess 7 in the oscillating area 10 can be achieved by a corresponding thickness of the plate mentioned which exceeds the thickness of the suction valve lamella 9, in the clamping area 12 this height can be reduced to a value corresponding to the thickness of the suction valve lamella 9 by an insert.
  • the two tabs 16 it is possible to use only one for the central plane 15 provide symmetrical tab, which is provided on both sides with guide surfaces.
  • the valve plate 1 can also form part of the cylinder head, the latter, as is known, must have mounting options for the pressure valve.
  • the piston compressor is equipped with a linearly displaceable suction valve lamella (9) which, by linear displacement, overlaps the suction valve openings (11) and releases the pressure valve openings (13) and a working position which at least partially releases the suction valve openings (11) and at least partially covers the pressure valve openings (13) Idle position is adjustable.
  • guide surfaces (17, 17 ') are provided on the two ends lying in the direction of movement parallel to the displacement direction, which have corresponding mating surfaces on the valve plate (1) or parts connected to it to be in sliding engagement.
  • Piston drives (27) are provided for displacing the suction valve lamella (9), the axial direction of which runs parallel to the displacement direction and which are coupled to the suction valve lamella (9) by means of pins (24).

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

Claims (7)

  1. Compresseur à pistons permettant une économie d'énergie, notamment pour l'alimentation en air comprimé dans des véhicules automobiles, comportant un dispositif de marche à vide, pouvant être commuté en fonction de la pression, pour la soupape d'aspiration équipée d'une lame (9), et dans lequel la lame (9) de la soupape d'aspiration, du compresseur à pistons, peut être déplacée selon un déplacement rectiligne perpendiculairement à l'axe (6) du cylindre, qui lui est associé, dans une position de travail dans laquelle elle recouvre les ouvertures (11) d'un plateau (1) de la soupape d'aspiration et libère les ouvertures (13) d'une soupape de refoulement, et une position de marche à vide, dans laquelle elle libère au moins partiellement les ouvertures (11) de la soupape d'aspiration et recouvre au moins partiellement les ouvertures (13) de la soupape de refoulement, et un dispositif (27) d'entraînement pneumatique du piston pour déplacer la lame (9) de la soupape d'aspiration à l'encontre de la force d'un ressort (26), de sa position de travail dans la position de marche à vide, caractérisé par le fait que la lame (9) de la soupape d'aspiration comporte, à proximité de ses extrémités, lorsqu'on regarde dans sa direction de déplacement, des surfaces de guidage (17, 17') qui sont parallèles à la direction de déplacement et à l'axe (6) du cylindre et qui s'appliquent, selon une liaison de translation, contre des surfaces antagonistes (18,18'), qui sont disposées sur le plateau (1) de la soupape ou sur des parties retenues de façon fixe sur ce plateau, et sont parallèles aux surfaces de guidage.
  2. Compresseur à pistons suivant la revendication 1, caractérisé par le fait qu'aux deux extrémités de la lame (9) de la soupape d'aspiration sont prévues respectivement deux surfaces de guidage (17,17') et des surfaces antagonistes (18,18') qui leur sont associées et qui sont disposées symétriquement l'une de l'autre par rapport à un plan médian (15) qui s'étend dans la direction de déplacement et contient l'axe (6) du cylindre.
  3. Compresseur à pistons suivant la revendication 1, caractérisé par le fait que la lame (9) de la soupape d'aspiration, qui est réalisée avec une forme essentiellement annulaire, comme cela est connu en soi, est accouplée, au niveau de son serrage (zone de serrage 12) à au moins un dispositif (27) d'entraînement de piston, qui possède un axe parallèle à la direction de déplacement, et comporte, en vis-à-vis, dans sa partie oscillante (10), au moins une patte saillante (16), qui possède au moins d'un côté une surface de guidage (17).
  4. Compresseur à pistons suivant la revendication 1, caractérisé par le fait que la lame (9) de la soupape d'aspiration est accouplée à deux dispositifs (27) d'entraînement de pistons et comporte deux pattes (16), qui, respectivement, sont disposées symétriquement par rapport au plan médian.
  5. Compresseur à pistons suivant la revendication 3 ou 4, caractérisé par le fait que chaque dispositif (27) d'entraînement de piston comporte une partie de guidage (22) qui est reliée à un piston (20) et est guidée de manière à être déplaçable dans le plateau (1) de la soupape, est accouplée à la lame (9) de la soupape d'aspiration, et est chargée par le ressort (26) dans la direction de déplacement en direction de la position de travail de la lame (9) de la soupape d'aspiration et est supportée, dans la direction de déplacement opposée, par une butée (23), dans une position qui correspond à la position de marche à vide de la lame (9) de la soupape d'aspiration.
  6. Compresseur à pistons suivant la revendication 5, caractérisé par le fait que le piston (20) est disposé de manière à ce que son axe coïncide avec celui de la partie de guidage essentiellement cylindrique (22), qui est éventuellement réalisée d'un seul tenant avec le piston, et est guidée dans un cylindre (19) disposé dans le plateau (1) de soupape.
  7. Compresseur à pistons suivant la revendication 5 ou 6, caractérisé par le fait que la partie de guidage (22) est accouplée à la lame (9) de la soupape d'aspiration, qui est disposée d'une manière décalée par rapport à l'axe du dispositif d'entraînement du piston, dans la direction de l'axe (6) du cylindre, au moyen d'une broche (24) qui s'étend parallèlement à l'axe (6) du cylindre.
EP92118157A 1991-11-25 1992-10-23 Compresseur à pistons économe en énergie Expired - Lifetime EP0544105B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4138664 1991-11-25
DE4138664A DE4138664A1 (de) 1991-11-25 1991-11-25 Energiesparender kolbenverdichter

Publications (2)

Publication Number Publication Date
EP0544105A1 EP0544105A1 (fr) 1993-06-02
EP0544105B1 true EP0544105B1 (fr) 1995-03-08

Family

ID=6445497

Family Applications (1)

Application Number Title Priority Date Filing Date
EP92118157A Expired - Lifetime EP0544105B1 (fr) 1991-11-25 1992-10-23 Compresseur à pistons économe en énergie

Country Status (4)

Country Link
EP (1) EP0544105B1 (fr)
DE (2) DE4138664A1 (fr)
ES (1) ES2069361T3 (fr)
RU (1) RU2101569C1 (fr)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102013006138A1 (de) * 2013-04-10 2014-10-16 Knorr-Bremse Systeme für Nutzfahrzeuge GmbH Einrichtung zur Leistungseinsparung bei einem Kolbenverdichter

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1628173A1 (de) * 1968-01-17 1971-08-05 Licentia Gmbh Kompressorantrieb
DE3909531A1 (de) * 1988-12-08 1990-06-13 Knorr Bremse Ag Einrichtung zur leistungseinsparung bei kolbenverdichtern, insbesondere fuer die drucklufterzeugung in kraftfahrzeugen
DE3904172A1 (de) * 1989-02-11 1990-08-16 Wabco Westinghouse Fahrzeug Ventillamelle

Also Published As

Publication number Publication date
DE4138664A1 (de) 1993-05-27
EP0544105A1 (fr) 1993-06-02
RU2101569C1 (ru) 1998-01-10
DE59201604D1 (de) 1995-04-13
ES2069361T3 (es) 1995-05-01

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