WO2008125155A1 - Vacuum pump - Google Patents

Vacuum pump Download PDF

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Publication number
WO2008125155A1
WO2008125155A1 PCT/EP2008/000103 EP2008000103W WO2008125155A1 WO 2008125155 A1 WO2008125155 A1 WO 2008125155A1 EP 2008000103 W EP2008000103 W EP 2008000103W WO 2008125155 A1 WO2008125155 A1 WO 2008125155A1
Authority
WO
WIPO (PCT)
Prior art keywords
leaf spring
vacuum pump
pump according
spring
housing
Prior art date
Application number
PCT/EP2008/000103
Other languages
German (de)
French (fr)
Inventor
Martin Thoma
Willi Schneider
Torsten Helle
Original Assignee
Joma-Hydromechanic 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 Joma-Hydromechanic Gmbh filed Critical Joma-Hydromechanic Gmbh
Priority to EP08701036A priority Critical patent/EP2122176B1/en
Priority to AT08701036T priority patent/ATE524655T1/en
Publication of WO2008125155A1 publication Critical patent/WO2008125155A1/en

Links

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
    • F04C18/30—Rotary-piston pumps specially adapted for elastic fluids having the characteristics covered by two or more of groups F04C18/02, F04C18/08, F04C18/22, F04C18/24, F04C18/48, or having the characteristics covered by one of these groups together with some other type of movement between co-operating members
    • F04C18/34—Rotary-piston pumps specially adapted for elastic fluids having the characteristics covered by two or more of groups F04C18/02, F04C18/08, F04C18/22, F04C18/24, F04C18/48, or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having the movement defined in group F04C18/08 or F04C18/22 and relative reciprocation between the co-operating members
    • F04C18/344—Rotary-piston pumps specially adapted for elastic fluids having the characteristics covered by two or more of groups F04C18/02, F04C18/08, F04C18/22, F04C18/24, F04C18/48, or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having the movement defined in group F04C18/08 or F04C18/22 and relative reciprocation between the co-operating members with vanes reciprocating with respect to the inner member
    • F04C18/3441—Rotary-piston pumps specially adapted for elastic fluids having the characteristics covered by two or more of groups F04C18/02, F04C18/08, F04C18/22, F04C18/24, F04C18/48, or having the characteristics covered by one of these groups together with some other type of movement between co-operating members having the movement defined in group F04C18/08 or F04C18/22 and relative reciprocation between the co-operating members with vanes reciprocating with respect to the inner member the inner and outer member being in contact along one line or continuous surface substantially parallel to the axis of rotation
    • 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
    • F04C29/00—Component parts, details or accessories of pumps or pumping installations, not provided for in groups F04C18/00 - F04C28/00
    • F04C29/12—Arrangements for admission or discharge of the working fluid, e.g. constructional features of the inlet or outlet
    • F04C29/124—Arrangements for admission or discharge of the working fluid, e.g. constructional features of the inlet or outlet with inlet and outlet valves specially adapted for rotary or oscillating piston pumps
    • F04C29/126—Arrangements for admission or discharge of the working fluid, e.g. constructional features of the inlet or outlet with inlet and outlet valves specially adapted for rotary or oscillating piston pumps of the non-return type
    • F04C29/128—Arrangements for admission or discharge of the working fluid, e.g. constructional features of the inlet or outlet with inlet and outlet valves specially adapted for rotary or oscillating piston pumps of the non-return type of the elastic type, e.g. reed valves
    • 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
    • F04C2220/00—Application
    • F04C2220/10—Vacuum

Definitions

  • the invention relates to a vacuum pump with a cup-shaped housing, a rotor rotatably mounted eccentrically in the housing, a rotatably mounted in the rotor orthogonal to the axis of rotation, which abuts with its wing tips on a working space bounding inner peripheral surface of the housing while the working space in a suction chamber and a Pressure chamber divided, and the suction chamber with an air inlet opening and the pressure chamber are provided with an air outlet opening, wherein the
  • Air outlet opening is provided with an outlet valve and the outlet valve as a closing member has a cantilevered leaf spring.
  • Vacuum pumps with such a structure are known, for example, from DE 10 2004 034 926 B3. They usually have a housing in which a rotor is rotatably mounted, wherein the rotor is located in a working space. Such vacuum pumps are used inter alia in vehicles, where, for example, the motor of the motor vehicle rotates the rotor. These vacuum pumps are lubricated with oil, which also serves to seal the sealing gap between the wing and working space in order to achieve high efficiency.
  • an outlet valve is provided, which is designed in the manner of a leaf spring.
  • This leaf spring presses on the outside of the air outlet and closes it.
  • the leaf spring can be bent over the prevailing pressure in the pressure chamber to the outside. Thereby the compressed air is expelled from the pressure space into the pressure line.
  • Such a device is known for example from DE 40 19 854 B4. With this vacuum pump it has been found that with leaf springs closed air outlet openings, which are not completely covered when sweeping the wing, relatively high losses occur.
  • the invention is therefore based on the object to provide a vacuum pump, wherein it is ensured that the air compressed in the pressure chamber is completely discharged into the pressure line and is not transferred to the pressure chamber located behind the wing.
  • the outlet valve has a leaf spring which does not consist, as in the prior art, of a leaf spring having a constant spring constant. Rather, the leaf spring according to the invention has one starting from the clamping point changing spring constant. This means that the free end of the leaf spring can be lifted off the outlet opening with a relatively small force, whereas for the further lifting of the leaf spring the force required for this increases disproportionately. As a result, the advantage is achieved that only the portion of the leaf spring is lifted from the outlet opening, which is required for the outlet of the compressed fluid. Too large an opening of the exhaust valve is effectively prevented by the clamping force of the leaf spring towards growing force required to lift the leaf spring.
  • a change in the spring characteristic or the spring constant can take place, for example, by virtue of the fact that the leaf spring has changing spring properties over its length, which can be achieved, for example, by targeted hardening of different regions of the leaf spring.
  • the leaf spring is designed as a rectangular spring, triangular spring or trapezoidal spring. Already by the shape of the spring can be specifically acted on the stiffness. It should only be noted that the outlet opening is completely covered by the leaf spring.
  • a further variant according to the invention provides that the leaf spring is a simple or layered leaf spring.
  • a layered leaf spring two or more sheets are stacked on top of each other, either of equal length or graduated lengths. The leaves are attached to the clamping point and extend, with different lengths, different distances away from this. As a result, the rigidity of the free end of the leaf spring is selectively increased in the direction of the clamping point.
  • the friction between the blades can be used to control the opening of the valve.
  • the leaf spring has a constant or a thickness which decreases starting from the clamping point.
  • the thickness of the leaf spring can change continuously, but preferably in stages. The production takes place, for example, by gradual rolling of the individual sheets.
  • a variant of the invention provides that in a layered leaf spring, the thickness of the individual sheets is equal or unequal. Especially with uneven thick leaves, the thickness can be greater for shorter leaves.
  • the leaf spring made of metal or plastic.
  • this can also be composed of a combination of plastic and metal leaves.
  • the long leaves are made of plastic, whereas the short leaves are made of metal.
  • a further variant of the invention provides that in a layered leaf spring, the leaves are blasted with decreasing length. This means that the leaves are curved in the direction of the longer leaf. Also by this measure, the rigidity of the leaf spring is increased in the direction of the clamping point.
  • the leaf spring in the sealing plane is partially circular or kidney-shaped bent. This is especially the case when the outlet opening is located in the bottom of the housing. If the outlet opening is located in the peripheral wall of the housing, then the above-mentioned measures are respectively adapted with regard to the curvature of the peripheral wall. This means that the leaf spring from the outset has the curvature of the peripheral wall or the outlet opening.
  • Figure 1 is a vacuum pump with removed housing cover
  • FIG. 2 shows the rear side of the vacuum pump, the drive of the rotor and the outlet valve
  • Figure 3 is an enlarged view of the exhaust valve prior to assembly
  • FIG. 4 shows the outlet valve according to FIG. 3 in the assembled position.
  • FIG. 1 In the figure 1 is denoted by the reference numeral 10, a vacuum pump, in which the housing 12 is shown without housing cover. This housing cover can be seen beginning in Figure 2.
  • the housing 12 has a suction port 14, which opens into an interior 16.
  • a generally designated 18 rotor In this interior 16 is a generally designated 18 rotor, in which a wing 20 is mounted orthogonal to the axis of rotation 21 slidably.
  • the rotor 18 has a rotor housing 24, with which it bears against an inner circumferential surface 22 of the working space 30.
  • the rotor 18 passes through the housing 12, in particular a bottom 26 of the interior 18, via a drive opening and projects out of the housing 12 on the rear side, so that it can be rotated by means of a drive (not shown) on a coupling 28 (FIG.
  • the interior 16 is divided by the wing 20 into a suction chamber 32 and a pressure chamber 34.
  • the direction of rotation of the rotor 20 is indicated by an arrow 36.
  • the in the pressure chamber 34 located and arranged in the bottom 26 of the housing 12 air outlet opening 38 is partially visible. This outlet opening 38 could also be provided in the peripheral surface 22.
  • FIG. 2 shows the rear side of the housing 12 of the vacuum pump 10 and shows the outlet valve 40 located behind the air outlet opening 38.
  • This outlet valve 40 has a valve stop 42, which limits the deflection of a leaf spring 44 designed as a closing member 46.
  • this leaf spring 44 lies directly on the outside of the outlet opening 38 and closes it, as can be seen in FIG. With a screw 48, not only the valve stop 42, but also the leaf spring 44 is secured to the housing 12 at its clamping point 50.
  • the leaf spring 44 consists of a total of four blades 52 to 58, each of which has a fastening opening 60 for the passage of the screw 48 at its clamping point 50 and which lie above one another starting from this fastening opening 60 and in the direction of the free end 62 of the sheet 52 extend.
  • the outlet opening 38 is located in the bottom 26 of the working space 30, the outlet opening 38 and thus also the leaf spring 44 have a part-circular or kidney-shaped shape and are curved around the rotor 18.
  • the blade 52 is immediately adjacent the discharge opening 38 and rests on this and closes it.
  • the blade 52 is engaged behind by the blade 54, which bears against the opposite side. However, the blade 54 has a shorter length, so that the blade 52 projects beyond the blade 54 over a certain distance.
  • the leaves 56 and 58 are constructed accordingly and engage behind the sheet 54 and the sheet 56th
  • the free end 32 of the blade 52 is rounded and the blades 54, 56 and 58, although partially curved, but with respect to the curvature of its longitudinal axis has a rectangular shape. It is also conceivable that the leaves are directed 52 to 58 triangular with the tip to the free end 62 or trapezoidal. Further, the leaves 54 to 58 may be blasted, that is, bent or curved in the direction of the respective underlying leaves 52 to 56. In addition, there is the possibility that the respective projecting ends of the leaves 52 to 56 have a decreasing towards the free end 62 thickness.
  • the material of the For example, sheet 52 may be plastic, whereas the materials of the other sheets 54-58 may be a metal. Different spring rates or stiffnesses of the individual blades 52 to 58 are also possible.
  • FIG. 4 shows the leaf spring 44 in the assembled position, in which the leaves 52 to 58 lie one above the other. It is also conceivable to produce a one-piece leaf spring 44 with a stepped thickness. The thickness can also decrease continuously from the clamping point 50 in the direction of the free end 62.

Abstract

The invention relates to a vacuum pump comprising a crucible-shaped housing, a rotor mounted eccentrically rotatably in the housing, a blade (20) supported displaceably perpendicular to the rotational axis in the rotor, the blade having the blade tips thereof resting against an internal circumferential surface delimiting a working space, thus dividing the working space into a suction space (32) and a pressure space (34), and the suction space being provided with an air inlet opening and the pressure space being provided with an air outlet opening, wherein the air outlet opening is provided with an outlet valve and the outlet valve (40) has a leaf spring (44) clamped on one side as a closing element, wherein the spring characteristic curve of the leaf spring changes from the clamped location (50) in the direction of the free end (62).

Description

Titel : VakuumpumpeTitle: Vacuum pump
Beschreibungdescription
Die Erfindung betrifft eine Vakuumpumpe mit einem topfförmigen Gehäuse, einem exzentrisch im Gehäuse drehbar gelagerten Rotor, einem im Rotor orthogonal zur Drehachse verschieblich gelagerten Flügel, der mit seinen Flügelspitzen an einer einen Arbeitsraum begrenzenden Innenumfangsflache des Gehäuses anliegt und dabei den Arbeitsraum in einen Saugraum und einen Druckraum unterteilt, und der Saugraum mit einer Lufteinlassöffnung und der Druckraum mit einer Luftauslassöffnung versehen sind, wobei dieThe invention relates to a vacuum pump with a cup-shaped housing, a rotor rotatably mounted eccentrically in the housing, a rotatably mounted in the rotor orthogonal to the axis of rotation, which abuts with its wing tips on a working space bounding inner peripheral surface of the housing while the working space in a suction chamber and a Pressure chamber divided, and the suction chamber with an air inlet opening and the pressure chamber are provided with an air outlet opening, wherein the
Luftauslassöffnung mit einem Auslassventil versehen ist und das Auslassventil als Schließorgan eine einseitig eingespannte Blattfeder aufweist.Air outlet opening is provided with an outlet valve and the outlet valve as a closing member has a cantilevered leaf spring.
Vakuumpumpen mit einem derartigen Aufbau sind zum Beispiel aus der DE 10 2004 034 926 B3 bekannt. Sie weisen in der Regel ein Gehäuse auf, in welchem ein Rotor drehbar gelagert ist, wobei sich der Rotor in einem Arbeitsraum befindet. Derartige Vakuumpumpen werden unter anderem auch in Fahrzeugen eingesetzt, wo zum Beispiel der Motor des Kraftfahrzeugs den Rotor in Drehung versetzt. Diese Vakuumpumpen werden mit Öl geschmiert, welches auch dazu dient, den Dichtspalt zwischen Flügel und Arbeitsraum abzudichten, um einen hohen Wirkungsgrad zu erzielen.Vacuum pumps with such a structure are known, for example, from DE 10 2004 034 926 B3. They usually have a housing in which a rotor is rotatably mounted, wherein the rotor is located in a working space. Such vacuum pumps are used inter alia in vehicles, where, for example, the motor of the motor vehicle rotates the rotor. These vacuum pumps are lubricated with oil, which also serves to seal the sealing gap between the wing and working space in order to achieve high efficiency.
An der Auslassöffnung ist ein Auslassventil vorgesehen, welches nach Art einer Blattfeder ausgebildet ist. Diese Blattfeder drückt von außen auf die Luftauslassöffnung und verschließt diese. Die Blattfeder kann über den im Druckraum herrschenden Überdruck nach außen aufgebogen werden. Dadurch wird die komprimierte Luft aus dem Druckraum in die Druckleitung ausgestoßen. Eine derartige Vorrichtung ist zum Beispiel aus der DE 40 19 854 B4 bekannt. Bei dieser Vakuumpumpe hat sich herausgestellt, dass bei mit Blattfedern verschlossenen Luftauslassöffnungen, welche beim Überstreichen des Flügels nicht vollständig abgedeckt werden, relativ hohe Verluste auftreten. Dies liegt darin begründet, dass dann, wenn der Flügel die Luftauslassöffnung überfährt und die Blattfeder von der ausströmenden, komprimierten Luft in die geöffnete Stellung bewegt wird, die Auslassöffnung vollständig geöffnet wird, d.h. hinter dem Flügel für den nachfolgenden Druckraum ebenfalls offen ist, so dass komprimierte Luft aus dem vor dem Flügel sich befindenden Druckraum nicht in die Druckleitung, sondern in den hinter dem Flügel sich befindenden Druckraum überströmt, in welchem die Luft einen wesentlich niedrigeren Druck aufweist. Es kann sogar bereits in die Druckleitung abgeförderte Luft in diesen hinter dem Flügel sich befindenden Druckraum zurück strömen, was zu erheblichen Druckverlusten führt.At the outlet opening an outlet valve is provided, which is designed in the manner of a leaf spring. This leaf spring presses on the outside of the air outlet and closes it. The leaf spring can be bent over the prevailing pressure in the pressure chamber to the outside. Thereby the compressed air is expelled from the pressure space into the pressure line. Such a device is known for example from DE 40 19 854 B4. With this vacuum pump it has been found that with leaf springs closed air outlet openings, which are not completely covered when sweeping the wing, relatively high losses occur. This is because, when the wing passes over the air outlet opening and the leaf spring is moved from the outflowing, compressed air to the open position, the outlet opening is fully opened, ie behind the wing for the subsequent pressure chamber is also open, so that compressed air from the located in front of the wing pressure chamber is not in the pressure line, but in the behind the wing located pressure chamber overflowed, in which the air has a much lower pressure. It can even flow back into the pressure line conveyed air in this behind the wing located pressure chamber back, resulting in significant pressure losses.
Der Erfindung liegt daher die Aufgabe zugrunde, eine Vakuumpumpe bereitzustellen, bei welcher sichergestellt ist, dass die im Druckraum komprimierte Luft vollständig in die Druckleitung ausgestoßen und nicht in den hinter dem Flügel sich befindenden Druckraum übergeleitet wird.The invention is therefore based on the object to provide a vacuum pump, wherein it is ensured that the air compressed in the pressure chamber is completely discharged into the pressure line and is not transferred to the pressure chamber located behind the wing.
Diese Aufgabe wird mit einer Vakuumpumpe der eingangs genannten Art erfindungsgemäß dadurch gelöst, dass die Federkennlinie der Blattfeder sich von der Einspannstelle in Richtung des freien Endes ändert.This object is achieved with a vacuum pump of the type mentioned according to the invention that the spring characteristic of the leaf spring changes from the clamping point in the direction of the free end.
Bei der erfindungsgemäßen Vakuumpumpe weist das Auslassventil eine Blattfeder auf, die nicht, wie beim Stand der Technik, aus einer eine konstante Federkonstante aufweisenden Blattfeder besteht. Vielmehr besitzt die erfindungsgemäße Blattfeder eine von der Einspannstelle ausgehend sich ändernden Federkonstante . Dies bedeutet, dass das freie Ende der Blattfeder mit einer relativ kleinen Kraft von der Auslassöffnung abgehoben werden kann, wohingegen für das weitere Abheben der Blattfeder die hierfür erforderliche Kraft überproportional zunimmt. Hierdurch wird der Vorteil erreicht, dass lediglich der Bereich der Blattfeder von der Auslassöffnung abgehoben wird, der für den Auslass des komprimierten Fluids erforderlich ist. Ein zu großes Öffnen des Auslassventils wird durch die zur Einspannstelle der Blattfeder hin wachsende erforderliche Kraft zum Abheben der Blattfeder wirksam verhindert.In the case of the vacuum pump according to the invention, the outlet valve has a leaf spring which does not consist, as in the prior art, of a leaf spring having a constant spring constant. Rather, the leaf spring according to the invention has one starting from the clamping point changing spring constant. This means that the free end of the leaf spring can be lifted off the outlet opening with a relatively small force, whereas for the further lifting of the leaf spring the force required for this increases disproportionately. As a result, the advantage is achieved that only the portion of the leaf spring is lifted from the outlet opening, which is required for the outlet of the compressed fluid. Too large an opening of the exhaust valve is effectively prevented by the clamping force of the leaf spring towards growing force required to lift the leaf spring.
Eine Änderung der Federkennlinie beziehungsweise der Federkonstanten kann erfindungsgemäß zum Beispiel dadurch erfolgen, dass die Blattfeder über ihre Länge sich ändernde Federeigenschaften aufweist, was zum Beispiel durch eine gezielte Härtung unterschiedlicher Bereiche der Blattfeder erfolgen kann.According to the invention, a change in the spring characteristic or the spring constant can take place, for example, by virtue of the fact that the leaf spring has changing spring properties over its length, which can be achieved, for example, by targeted hardening of different regions of the leaf spring.
Bei einer erfindungsgemäßen Weiterbildung ist die Blattfeder als Rechteckfeder, Dreieckfeder oder Trapezfeder ausgebildet. Bereits durch die Form der Feder kann gezielt auf deren Steifigkeit eingewirkt werden. Zu beachten ist lediglich, dass die Auslassöffnung von der Blattfeder vollständig abgedeckt wird.In a further development of the invention, the leaf spring is designed as a rectangular spring, triangular spring or trapezoidal spring. Already by the shape of the spring can be specifically acted on the stiffness. It should only be noted that the outlet opening is completely covered by the leaf spring.
Eine weitere erfindungsgemäße Variante sieht vor, dass die Blattfeder eine einfache oder geschichtete Blattfeder ist. Bei einer geschichteten Blattfeder liegen zwei oder mehrere Blätter übereinander, die entweder die gleiche Länge oder aber abgestufte Längen aufweisen. Die Blätter sind an der Einspannstelle befestigt und erstrecken sich, bei unterschiedlichen Längen, unterschiedlich weit von dieser weg. Hierdurch wird gezielt die Steifigkeit vom freien Ende der Blattfeder in Richtung zu der Einspannstelle erhöht. Außerdem kann die Reibung zwischen den Blättern zur Steuerung der Öffnung des Ventils verwendet werden.A further variant according to the invention provides that the leaf spring is a simple or layered leaf spring. In a layered leaf spring, two or more sheets are stacked on top of each other, either of equal length or graduated lengths. The leaves are attached to the clamping point and extend, with different lengths, different distances away from this. As a result, the rigidity of the free end of the leaf spring is selectively increased in the direction of the clamping point. In addition, the friction between the blades can be used to control the opening of the valve.
Bei einer erfindungsgemäßen Weiterbildung ist vorgesehen, dass die Blattfeder eine Konstante oder eine von der Einspannstelle ausgehend abnehmende Dicke aufweist. Dabei kann sich die Dicke der Blattfeder kontinuierlich, bevorzugt aber in Stufen, ändern. Die Herstellung erfolgt zum Beispiel durch abgestuftes Walzen der einzelnen Blätter.In a development according to the invention, it is provided that the leaf spring has a constant or a thickness which decreases starting from the clamping point. In this case, the thickness of the leaf spring can change continuously, but preferably in stages. The production takes place, for example, by gradual rolling of the individual sheets.
Eine erfindungsgemäße Variante sieht vor, dass bei einer geschichteten Blattfeder die Dicke der einzelnen Blätter gleich oder ungleich ist. Insbesondere bei ungleich dicken Blättern kann die Dicke bei kürzeren Blättern größer sein.A variant of the invention provides that in a layered leaf spring, the thickness of the individual sheets is equal or unequal. Especially with uneven thick leaves, the thickness can be greater for shorter leaves.
Bevorzugt besteht die Blattfeder aus Metall oder Kunststoff. Bei geschichteten Blattfedern kann diese auch aus einer Kombination von aus Kunststoff und aus Metall bestehenden Blättern aufgebaut sein. Insbesondere bestehen die langen Blätter aus Kunststoff, wohingegen die kurzen Blätter aus Metall bestehen.Preferably, the leaf spring made of metal or plastic. In layered leaf springs this can also be composed of a combination of plastic and metal leaves. In particular, the long leaves are made of plastic, whereas the short leaves are made of metal.
Eine weitere erfindungsgemäße Variante sieht vor, dass bei einer geschichteten Blattfeder die Blätter mit abnehmender Länge gesprengt sind. Dies bedeutet, dass die Blätter in Richtung des jeweils längeren Blattes gekrümmt sind. Auch durch diese Maßnahme wird die Steifigkeit der Blattfeder in Richtung der Einspannstelle erhöht.A further variant of the invention provides that in a layered leaf spring, the leaves are blasted with decreasing length. This means that the leaves are curved in the direction of the longer leaf. Also by this measure, the rigidity of the leaf spring is increased in the direction of the clamping point.
Bevorzugt ist die Blattfeder in der Abdichtebene teilkreisförmig oder nierenförmig gebogen. Dies ist insbesondere dann der Fall, wenn die Auslassöffnung sich im Boden des Gehäuses befindet. Befindet sich die Auslassöffnung in der Umfangswand des Gehäuses, dann sind die oben erwähnten Maßnahmen jeweils bezüglich der Krümmung der Umfangswand angepasst. Dies bedeutet, dass die Blattfeder von vornherein die Krümmung der Umfangswand beziehungsweise der Auslassöffnung aufweist.Preferably, the leaf spring in the sealing plane is partially circular or kidney-shaped bent. This is especially the case when the outlet opening is located in the bottom of the housing. If the outlet opening is located in the peripheral wall of the housing, then the above-mentioned measures are respectively adapted with regard to the curvature of the peripheral wall. This means that the leaf spring from the outset has the curvature of the peripheral wall or the outlet opening.
Weitere Vorteile, Merkmale und Einzelheiten der Erfindung ergeben sich aus den Unteransprüchen sowie der nachfolgenden Beschreibung, in der unter Bezugnahme auf die Zeichnung ein besonders bevorzugtes Ausführungsbeispiel im Einzelnen beschrieben ist. Dabei können die in der Zeichnung dargestellten sowie in den Ansprüchen und in der Beschreibung erwähnten Merkmale jeweils einzeln für sich oder in beliebiger Kombination erfindungswesentlich sein.Further advantages, features and details of the invention will become apparent from the subclaims and the following description in which, with reference to the drawing, a particularly preferred embodiment is described in detail. The features shown in the drawing and mentioned in the claims and in the description may each be essential to the invention individually or in any combination.
In der Zeichnung zeigen:In the drawing show:
Figur 1 eine Vakuumpumpe mit abgenommenem Gehäusedeckel;Figure 1 is a vacuum pump with removed housing cover;
Figur 2 die Rückseite der Vakuumpumpe, den Antrieb des Rotors sowie das Auslassventil zeigend;FIG. 2 shows the rear side of the vacuum pump, the drive of the rotor and the outlet valve;
Figur 3 eine vergrößerte Darstellung des Auslassventils vor dem Zusammenbau; undFigure 3 is an enlarged view of the exhaust valve prior to assembly; and
Figur 4 das Auslassventil gemäß Figur 3 in zusammengebauter Stellung.FIG. 4 shows the outlet valve according to FIG. 3 in the assembled position.
In der Figur 1 ist mit dem Bezugszeichen 10 eine Vakuumpumpe bezeichnet, bei welcher das Gehäuse 12 ohne Gehäusedeckel dargestellt ist. Dieser Gehäusedeckel ist ansatzweise in Figur 2 erkennbar. Das Gehäuse 12 besitzt einen Sauganschluss 14, der in einen Innenraum 16 ausmündet. In diesem Innenraum 16 befindet sich ein insgesamt mit 18 bezeichneter Rotor, in welchem ein Flügel 20 orthogonal zur Drehachse 21 verschieblich gelagert ist. Der Rotor 18 weist ein Rotorgehäuse 24 auf, mit dem er an einer Innenumfangsflache 22 des Arbeitsraums 30 anliegt. Der Rotor 18 durchgreift das Gehäuse 12, insbesondere einen Boden 26 des Innenraums 18, über eine Antriebsöffnung und ragt auf der Rückseite aus dem Gehäuse 12 heraus, so dass er mittels eines nicht dargestellten Antriebs an einer Kupplung 28 (Figur 2) in Drehung versetzt werden kann. Der Innenraum 16 wird vom Flügel 20 in einen Saugraum 32 und einen Druckraum 34 unterteilt. Die Drehrichtung des Rotors 20 ist mit einem Pfeil 36 angedeutet. Außerdem ist die im Druckraum 34 sich befindende und im Boden 26 des Gehäuses 12 angeordnete Luftauslassöffnung 38 teilweise erkennbar. Diese Auslassöffnung 38 könnte auch in der Umfangsflache 22 vorgesehen sein.In the figure 1 is denoted by the reference numeral 10, a vacuum pump, in which the housing 12 is shown without housing cover. This housing cover can be seen beginning in Figure 2. The housing 12 has a suction port 14, which opens into an interior 16. In this interior 16 is a generally designated 18 rotor, in which a wing 20 is mounted orthogonal to the axis of rotation 21 slidably. The rotor 18 has a rotor housing 24, with which it bears against an inner circumferential surface 22 of the working space 30. The rotor 18 passes through the housing 12, in particular a bottom 26 of the interior 18, via a drive opening and projects out of the housing 12 on the rear side, so that it can be rotated by means of a drive (not shown) on a coupling 28 (FIG. 2). The interior 16 is divided by the wing 20 into a suction chamber 32 and a pressure chamber 34. The direction of rotation of the rotor 20 is indicated by an arrow 36. In addition, the in the pressure chamber 34 located and arranged in the bottom 26 of the housing 12 air outlet opening 38 is partially visible. This outlet opening 38 could also be provided in the peripheral surface 22.
In der Figur 2 ist die Rückseite des Gehäuses 12 der Vakuumpumpe 10 dargestellt und es ist das hinter der Luftauslassöffnung 38 sich befindende Auslassventil 40 erkennbar. Dieses Auslassventil 40 besitzt einen Ventilanschlag 42, der die Auslenkung eines als Blattfeder 44 ausgebildeten Schließorgans 46 begrenzt. Diese Blattfeder 44 liegt, wie zum Beispiel aus Figur 3 ersichtlich, direkt auf der Außenseite der Auslassöffnung 38 auf und verschließt diese, was aus Figur 4 ersichtlich ist. Mit einer Schraube 48 ist nicht nur der Ventilanschlag 42, sondern auch die Blattfeder 44 an ihrer Einspannstelle 50 am Gehäuse 12 befestigt.FIG. 2 shows the rear side of the housing 12 of the vacuum pump 10 and shows the outlet valve 40 located behind the air outlet opening 38. This outlet valve 40 has a valve stop 42, which limits the deflection of a leaf spring 44 designed as a closing member 46. As can be seen, for example, from FIG. 3, this leaf spring 44 lies directly on the outside of the outlet opening 38 and closes it, as can be seen in FIG. With a screw 48, not only the valve stop 42, but also the leaf spring 44 is secured to the housing 12 at its clamping point 50.
Aus der Figur 3 ist ersichtlich, dass die Blattfeder 44 aus insgesamt vier Blättern 52 bis 58 besteht, die an ihrer Einspannstelle 50 jeweils eine Befestigungsöffnung 60 zum Durchtritt der Schraube 48 aufweisen und die ausgehend von dieser Befestigungsöffnung 60 übereinander liegen und in Richtung des freien Endes 62 des Blatts 52 erstrecken. Da sich die Auslassöffnung 38 im Boden 26 des Arbeitsraums 30 befindet, besitzen die Auslassöffnung 38 und somit auch die Blattfeder 44 eine teilkreisförmige beziehungsweise nierenförmige Gestalt und sind um den Rotor 18 gekrümmt. Das Blatt 52 ist der Auslassöffnung 38 unmittelbar benachbart und liegt auf dieser auf und verschließt sie. Das Blatt 52 wird vom Blatt 54 hintergriffen, welches an der gegenüberliegenden Seite anliegt. Jedoch besitzt das Blatt 54 eine geringere Länge, so dass das Blatt 52 das Blatt 54 über eine gewisse Wegstrecke überragt. Die Blätter 56 und 58 sind entsprechend aufgebaut und hintergreifen das Blatt 54 beziehungsweise das Blatt 56.It can be seen from FIG. 3 that the leaf spring 44 consists of a total of four blades 52 to 58, each of which has a fastening opening 60 for the passage of the screw 48 at its clamping point 50 and which lie above one another starting from this fastening opening 60 and in the direction of the free end 62 of the sheet 52 extend. Since the outlet opening 38 is located in the bottom 26 of the working space 30, the outlet opening 38 and thus also the leaf spring 44 have a part-circular or kidney-shaped shape and are curved around the rotor 18. The blade 52 is immediately adjacent the discharge opening 38 and rests on this and closes it. The blade 52 is engaged behind by the blade 54, which bears against the opposite side. However, the blade 54 has a shorter length, so that the blade 52 projects beyond the blade 54 over a certain distance. The leaves 56 and 58 are constructed accordingly and engage behind the sheet 54 and the sheet 56th
Dies hat zur Folge, dass zum Anheben des freien Endes 62 des Blatts 52 lediglich eine geringe Druckkraft in Richtung des Pfeils 64 erforderlich ist. Bei großem Volumenstrom wird zusätzlich zum freien Ende 62 des Blatts 52 auch das freie Ende des Blatts 54 und eventuell das freie Ende des Blatts 56 angehoben. Um die Blätter 54, 56 und 58 nacheinander anzuheben, muss die in Richtung des Pfeils 64 wirkende Druckkraft jedoch stark überproportional zunehmen. Hierdurch wird erreicht, dass lediglich das äußerste freie Ende 62 von der Auslassöffnung 38 abgehoben wird und die restliche Fläche der Auslassöffnung 38 weiterhin von der Blattfeder 44 verdeckt wird. Hierdurch wird verhindert, dass Luft aus dem Druckraum 34 vor dem Flügel 20 in den Saugraum 32 hinter den Flügel 20 überströmt.This has the consequence that only a small pressure force in the direction of the arrow 64 is required to lift the free end 62 of the blade 52. At high flow, in addition to the free end 62 of the blade 52 and the free end of the blade 54 and possibly the free end of the blade 56 is raised. In order to lift the sheets 54, 56 and 58 successively, however, the compressive force acting in the direction of the arrow 64 must increase greatly disproportionately. This ensures that only the outermost free end 62 is lifted from the outlet opening 38 and the remaining area of the outlet opening 38 is still covered by the leaf spring 44. This prevents that air flows from the pressure chamber 34 in front of the wing 20 in the suction chamber 32 behind the wings 20.
Aus den Figuren 3 und 4 ist erkennbar, dass das freie Ende 32 des Blatts 52 abgerundet ist und die Blätter 54, 56 und 58 zwar teilkreisförmig gebogen, aber bezüglich auf die Krümmung ihrer Längsachse eine Rechteckform aufweist. Es ist auch denkbar, dass die Blätter 52 bis 58 dreieckförmig mit der Spitze zum freien Ende 62 gerichtet oder trapezförmig ausgebildet sind. Ferner können die Blätter 54 bis 58 gesprengt, das heißt in Richtung auf die jeweils darunter liegenden Blätter 52 bis 56 gebogen beziehungsweise gekrümmt sein. Außerdem besteht die Möglichkeit, dass die jeweils überstehenden Enden der Blätter 52 bis 56 eine zum freien Ende 62 hin abnehmende Dicke aufweisen. Das Material des Blatts 52 kann zum Beispiel Kunststoff sein, wohingegen die Materialien der anderen Blätter 54 bis 58 ein Metall ist. Unterschiedliche Federraten oder Steifigkeiten der einzelnen Blätter 52 bis 58 sind ebenfalls möglich.From Figures 3 and 4 it can be seen that the free end 32 of the blade 52 is rounded and the blades 54, 56 and 58, although partially curved, but with respect to the curvature of its longitudinal axis has a rectangular shape. It is also conceivable that the leaves are directed 52 to 58 triangular with the tip to the free end 62 or trapezoidal. Further, the leaves 54 to 58 may be blasted, that is, bent or curved in the direction of the respective underlying leaves 52 to 56. In addition, there is the possibility that the respective projecting ends of the leaves 52 to 56 have a decreasing towards the free end 62 thickness. The material of the For example, sheet 52 may be plastic, whereas the materials of the other sheets 54-58 may be a metal. Different spring rates or stiffnesses of the individual blades 52 to 58 are also possible.
Die Figur 4 zeigt die Blattfeder 44 in der zusammengebauten Lage, in der die Blätter 52 bis 58 übereinander liegen. Es ist auch denkbar, eine einstückige Blattfeder 44 mit gestufter Dicke herzustellen. Die Dicke kann auch von der Einspannstelle 50 ausgehend kontinuierlich in Richtung des freien Endes 62 abnehmen.FIG. 4 shows the leaf spring 44 in the assembled position, in which the leaves 52 to 58 lie one above the other. It is also conceivable to produce a one-piece leaf spring 44 with a stepped thickness. The thickness can also decrease continuously from the clamping point 50 in the direction of the free end 62.
Mit der erfindungsgemäßen Vakuumpumpe 10 wird eine Rückströmung von komprimiertem Fluid in den Saugraum 32 effektiv vermindert. With the vacuum pump 10 according to the invention, a return flow of compressed fluid into the suction chamber 32 is effectively reduced.

Claims

Patentansprüche claims
1. Vakuumpumpe (10) mit einem topfförmigen Gehäuse (12), einem exzentrisch im Gehäuse (12) drehbar gelagerten Rotor (18), einem im Rotor (18) orthogonal zur DrehachseA vacuum pump (10) having a pot-shaped housing (12), a rotor (18) rotatably mounted eccentrically in the housing (12), one in the rotor (18) orthogonal to the axis of rotation
(21) verschieblich gelagerten Flügel (20), der mit seinen Flügelspitzen an einer einen Arbeitsraum (30) begrenzenden Innenumfangsflache (22) des Gehäuses (12) anliegt und dabei den Arbeitsraum (30) in einen Saugraum (32) und einen Druckraum (34) unterteilt und der Saugraum (32) mit einer Lufteinlassöffnung (14) und der Druckraum (34) mit einer Luftauslassöffnung (38) versehen sind, wobei die Luftauslassöffnung (38) mit einem Auslassventil (40) versehen ist und das Auslassventil (40) als Schließorgan (46) eine einseitig eingespannte Blattfeder (44) aufweist, dadurch gekennzeichnet, dass die Federkennlinie der Blattfeder (44) sich von der Einspannstelle (50) in Richtung des freien Endes (62) ändert.(21) displaceably mounted wings (20), which rests with its wing tips on a working space (30) defining inner peripheral surface (22) of the housing (12) while the working space (30) in a suction chamber (32) and a pressure chamber (34 ) and the suction space (32) having an air inlet opening (14) and the pressure chamber (34) with an air outlet opening (38) are provided, wherein the air outlet opening (38) is provided with an outlet valve (40) and the outlet valve (40) as Closing member (46) has a cantilevered leaf spring (44), characterized in that the spring characteristic of the leaf spring (44) from the clamping point (50) in the direction of the free end (62) changes.
2. Vakuumpumpe nach Anspruch 1, dadurch gekennzeichnet, dass die Blattfeder (44) eine Rechteckfeder, Dreieckfeder oder Trapezfeder ist.2. Vacuum pump according to claim 1, characterized in that the leaf spring (44) is a rectangular spring, triangular spring or trapezoidal spring.
3. Vakuumpumpe nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass die Blattfeder (44) eine einfache oder geschichtete Blattfeder (44) ist.3. Vacuum pump according to one of the preceding claims, characterized in that the leaf spring (44) is a simple or layered leaf spring (44).
4. Vakuumpumpe nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass die Blattfeder (44) eine konstante oder eine von der Einspannstelle (50) ausgehend abnehmende Dicke aufweist.4. Vacuum pump according to one of the preceding claims, characterized in that the leaf spring (44) has a constant or one of the clamping point (50), starting decreasing thickness.
5. Vakuumpumpe nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass bei einer geschichteten Blattfeder (44) die Dicke der einzelnen Blätter (52, 54, 56, 58) gleich oder ungleich ist.5. Vacuum pump according to one of the preceding claims, characterized in that in a layered Leaf spring (44), the thickness of the individual leaves (52, 54, 56, 58) is equal or unequal.
6. Vakuumpumpe nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass die Blattfeder (44) aus Metall oder Kunststoff oder einer Kombination besteht.6. Vacuum pump according to one of the preceding claims, characterized in that the leaf spring (44) consists of metal or plastic or a combination.
7. Vakuumpumpe nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass die Blattfeder (44) in der Abdichtfläche teilkreisförmig oder nierenförmig gebogen ist .7. Vacuum pump according to one of the preceding claims, characterized in that the leaf spring (44) is bent part-circular or kidney-shaped in the sealing surface.
8. Vakuumpumpe nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass bei einer geschichteten Blattfeder (44) die Blätter (52, 54, 56, 58) mit abnehmender Länge gesprengt sind.8. Vacuum pump according to one of the preceding claims, characterized in that in a layered leaf spring (44) the leaves (52, 54, 56, 58) are blown up with decreasing length.
9. Vakuumpumpe nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass das Auslassventil (40) mit der Blattfeder (44) sich im Boden (26) oder der Umfangswand (22) des Gehäuses (12) befinden. 9. Vacuum pump according to one of the preceding claims, characterized in that the outlet valve (40) with the leaf spring (44) in the bottom (26) or the peripheral wall (22) of the housing (12) are located.
PCT/EP2008/000103 2007-04-12 2008-01-09 Vacuum pump WO2008125155A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP08701036A EP2122176B1 (en) 2007-04-12 2008-01-09 Vacuum pump
AT08701036T ATE524655T1 (en) 2007-04-12 2008-01-09 VACUUM PUMP

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DE102007018247A DE102007018247A1 (en) 2007-04-12 2007-04-12 vacuum pump
DE102007018247.5 2007-04-12

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AT (1) ATE524655T1 (en)
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WO (1) WO2008125155A1 (en)

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DE102009016048B4 (en) * 2009-04-02 2018-05-30 Bayerische Motoren Werke Aktiengesellschaft Pump for a motor vehicle internal combustion engine and motor vehicle internal combustion engine with pump
WO2010145633A2 (en) * 2009-06-17 2010-12-23 Ixetic Hückeswagen Gmbh Vacuum pump
DE102010026032A1 (en) * 2010-07-03 2012-01-05 Mahle International Gmbh Flatter valve i.e. non-return valve, for use in rotary vane pump in brake booster in motor car, has blank holder whose form corresponds to bending line of single-sided clamped bending bar, which is designed as cantilever arm
DE102013104375A1 (en) * 2013-04-30 2014-10-30 Hella Kgaa Hueck & Co. vacuum pump
DE102015118022A1 (en) * 2015-10-22 2017-04-27 Pfeiffer Vacuum Gmbh Rotationsverdrängervakuumpumpe
DE102016210102A1 (en) * 2016-06-08 2017-12-14 Mahle International Gmbh Check valve for a vacuum pump
DE102017123695A1 (en) * 2017-10-11 2019-04-11 Schwäbische Hüttenwerke Automotive GmbH rotary pump
CN112901483A (en) * 2021-04-05 2021-06-04 杨文通 Cylinder block and pump/motor/air compressor/internal combustion engine using same

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US2689552A (en) * 1950-09-11 1954-09-21 Elmer C Kiekhaefer Reed valve for internal-combustion engines
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Also Published As

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EP2122176A1 (en) 2009-11-25
ATE524655T1 (en) 2011-09-15
DE102007018247A1 (en) 2008-10-16
EP2122176B1 (en) 2011-09-14

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