EP0630446B1 - Oil-sealed vacuum pump - Google Patents

Oil-sealed vacuum pump Download PDF

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Publication number
EP0630446B1
EP0630446B1 EP93903938A EP93903938A EP0630446B1 EP 0630446 B1 EP0630446 B1 EP 0630446B1 EP 93903938 A EP93903938 A EP 93903938A EP 93903938 A EP93903938 A EP 93903938A EP 0630446 B1 EP0630446 B1 EP 0630446B1
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EP
European Patent Office
Prior art keywords
valve
vacuum pump
switch
oil
pump according
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
EP93903938A
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German (de)
French (fr)
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EP0630446A1 (en
Inventor
Thomas Abelen
Josef Hodapp
Winfried Kaiser
Zoltan Szöcs
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
Balzers und Leybold Deutschland Holding AG
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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B37/00—Pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B25/00 - F04B35/00
    • F04B37/10—Pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B25/00 - F04B35/00 for special use
    • F04B37/14—Pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B25/00 - F04B35/00 for special use to obtain high vacuum
    • 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
    • F04C28/00—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids
    • F04C28/28—Safety arrangements; Monitoring
    • 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
    • F04C25/00—Adaptations of pumps for special use of pumps for elastic fluids
    • F04C25/02—Adaptations of pumps for special use of pumps for elastic fluids for producing high vacuum
    • 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
    • F04C29/02—Lubrication; Lubricant separation
    • F04C29/021—Control systems for the circulation of the lubricant

Definitions

  • the invention relates to an oil-sealed vacuum pump with the features of the preamble of patent claim 1.
  • Valves suction port valves installed in the inlet port are widely known and are controlled, for example, by centrifugal switches or by changing pressures (oil pressure, outlet pressure) when the pump is stopped.
  • suction nozzle valves are not required. They are operated in such a way that in the event of a power cut-off, intentionally or not, the valve located in the outlet, usually a check valve, and the valve located in the oil supply line, usually a solenoid valve, close. As a result, the scooping space of the vacuum pump is tightly sealed, so that the vacuum in the scooping space of the vacuum pump and thus also in the recipient is maintained when the power is switched off.
  • a vacuum pump with an oil channel is known, which is part of the rotor itself.
  • the oil channel is equipped with a centrifugal valve that is designed to prevent oil from being sucked into the pump's pump chamber when it is at a standstill. An intake of air in the recipient is not prevented; vacuum protection is also not achieved.
  • the present invention has for its object to operate a vacuum pump of the type mentioned in such a way that vacuum protection is not only guaranteed in the event of a power failure.
  • the rotary vane vacuum pump 1 shown in FIG. 1 has a pump housing 2 with a pumping chamber 3.
  • the scoop 3 In the scoop 3 is the rotatably arranged rotor 4, which Rotary valve 5, 6 leads.
  • the inlet connection 7 and the outlet connection 8 are located on the side of the rotor system 6.
  • the recipient, not shown, to be evacuated is connected to the inlet connection 7.
  • the outlet port 8 is equipped with the check valve 9, which always closes the outlet port 8 in a vacuum-tight manner when the pump does not deliver any fluids.
  • the oil supply line 11 also opens into the scooping chamber 3, via which the scooping chamber 3 is continuously supplied with oil from the schematically illustrated oil pan 12. Solenoid valve 13 is switched on in line 11.
  • the rotor 4 is coupled to a drive motor, not shown in FIG. 1. Simultaneously with the switching on and off of the drive motor, the valve 13 is actuated such that it is open when the current is switched on. When the power is switched off - also in the event of a power failure - the valve 13 is closed.
  • FIG. 2 In the functional circuit diagram shown in FIG. 2 for an exemplary embodiment according to the invention, essential components of a single-phase capacitor motor 14 are shown schematically, namely the motor coil 15 (main winding), the motor capacitor 16 and the motor coil 20 (auxiliary winding).
  • the voltage supply takes place via the lines 17, 18, which are connected to the AC voltage source 21 via the switch 19.
  • a temperature sensor 22 is also shown schematically. This is used in a known manner to protect the temperature of the motor 14. If the temperature exceeds a limit value, the motor is automatically switched off (indicated by arrow 23).
  • the valve 13 is also connected to the AC voltage source 21 via the lines 24, 25 and the switch 19. In the event of a power cut, a power failure or an impermissible motor temperature, the valve 13 is closed at the same time as the pump stops.
  • the coil 20 which is connected in series with the motor capacitor, serves as the speed-dependent sensor, via which the voltage U n , which is dependent on the speed n, drops.
  • the value of U n takes its maximum value at the engine idling speed. At speed 0, the value of U n is also small.
  • the value U n is fed to a logic 26, within which the value of U n is continuously compared with a target or limit value. As long as the value of U n is greater than the setpoint, a signal is not forwarded. If the value of U n falls below the setpoint value, then a relay 28 with the switch 29 is actuated via the line 27.
  • the switch 29 is located in the circuit formed by the lines 24, 25, in which the valve 13 is also switched on. The actuation of the relay 28, 29 takes place in such a way that the switch 29 is opened when the setpoint value monitored by the logic 26 is undershot. The result of this opening process is that the solenoid valve 13 closes, even when switch 19 remains closed. This ensures that the oil supply via the supply line 11 is also stopped if a mechanical defect occurs when the switch 19 is closed.
  • the setpoint value of the logic 26 is selected such that it corresponds to the value for U n at 20% of the idle speed of the drive motor 14. If, for example, a mechanical defect occurs in a vacuum pump with a drive motor whose idle speed is 1500 rpm, which causes the speed to drop to 300 rpm, then the switch 29 opens so that the solenoid valve 13 closes Oil supply to the pump chamber is therefore interrupted. This ensures that the vacuum in the connected recipient is maintained. If the pump starts again, the switch 29 and thus the valve 13 are automatically opened again.
  • the drive motor 14 heats up. After a short time, the drive motor 14 is assigned Thermal protection (22, 23) cause the current to be switched off so that the pump comes to a standstill.
  • the logic 26 and the relay 28, 29 are accommodated in a housing 31. They contain - apart from the switch 29 of the relay - no mechanical parts, so that the solution according to the invention is reliable and has a long service life. In addition, the solution according to the invention has the advantage that it works independently of the pressure in the recipient.
  • a semiconductor switch can also be provided, so that mechanical parts are completely eliminated. It is also possible to connect the logic 26 and the switch 29 to one another via an optical coupling link. Finally, it is possible to use a component that has both a logic and a switching function. Power semiconductors of this type are known per se under the name “smart power” module.

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

Abstract

The invention concerns a method of operating an oil-sealed vacuum pump (1) with an outlet nozzle (8) provided with a flap valve (9), an oil feed duct (11) which has a valve (13) and has its outlet in the suction chamber of the pump, an electric drive motor (14) for the rotor (4) with coils (15 and 20), and a capacitor (16). The valve (13) in the oil feed duct (11) is closed when the pump (1) is switched off or in the event of a power cut. To ensure that a vacuum is maintained even when a mechanical fault occurs, it is proposed that the valve (13) in the oil feed duct (11) should be controlled by the rotational speed of the rotor (4) and drive motor (14) so as to remain open at normal operating speed and to close when speed is reduced; the auxiliary coil (20) of the motor can serve as a sensor.

Description

Die Erfindung bezieht sich auf eine ölgedichtete Vakuumpumpe mit den Merkmalen des Oberbegriffs des Patentanspruchs 1.The invention relates to an oil-sealed vacuum pump with the features of the preamble of patent claim 1.

Beim Betrieb von Vakuumpumpen besteht generell das Bedürfnis, daß sowohl bei einem beabsichtigten als auch bei einem unbeabsichtigten Anhalten der Pumpe der an den Einlaßstutzen angeschlossene Rezipient nicht belüftet wird. Vielfach bekannt sind im Einlaßstutzen eingebaute Ventile (Saugstutzenventile) , die beispielsweise über Fliehkraftschalter oder sich beim Anhalten der Pumpe ändernde Drücke (Öldruck, Auslaßdruck) gesteuert werden.When operating vacuum pumps, there is a general need that the recipient connected to the inlet port is not ventilated both when the pump is intended and when it is stopped unintentionally. Valves (suction port valves) installed in the inlet port are widely known and are controlled, for example, by centrifugal switches or by changing pressures (oil pressure, outlet pressure) when the pump is stopped.

Bei Vakuumpumpen der eingangs erwähnten Art sind Saugstutzenventile nicht erforderlich. Sie werden derart betrieben, daß bei einer Stromabschaltung - beabsichtigt oder nicht - das im Auslaß befindliche Ventil, üblicherweise ein Rückschlagventil, sowie das in der Ölzuführungsleitung befindliche Ventil, üblicherweise ein Magnetventil, schließen. Dadurch ist der Schöpfraum der Vakuumpumpe dicht abgeschlossen, so daß das Vakuum im Schöpfraum der Vakuumpumpe und damit auch im Rezipienten bei einer Stromabschaltung aufrecht erhalten bleibt.In the case of vacuum pumps of the type mentioned in the introduction, suction nozzle valves are not required. They are operated in such a way that in the event of a power cut-off, intentionally or not, the valve located in the outlet, usually a check valve, and the valve located in the oil supply line, usually a solenoid valve, close. As a result, the scooping space of the vacuum pump is tightly sealed, so that the vacuum in the scooping space of the vacuum pump and thus also in the recipient is maintained when the power is switched off.

Tritt jedoch der Fall ein, daß der Rotor der Pumpe blokkiert, z.B. nach einem Schieberbruch oder nach einem Fressen des Rotors, ohne daß dieser Vorgang zunächst mit einem Stromausfall verbunden ist, dann bleibt das in der Ölzuführungsleitung befindliche Ventil offen. Über dieses Ventil gelangt Pumpenöl in den Schöpfraum und damit auch in den unter Vakuum stehenden Rezipienten. Die Folgen sind nicht nur eine Druckerhöhung im Rezipienten sondern auch eine Ölverseuchung des Rezipientens und der darin befindlichen Gegenstände.However, if the rotor of the pump becomes blocked, for example after a slide valve breaks or after a seizure of the rotor, without this process being initially connected to a power failure, the valve in the oil supply line remains open. Via this valve, pump oil reaches the scooping chamber and thus also the recipient, which is under vacuum. The consequences are not only an increase in pressure in the recipient but also an oil contamination of the recipient and the objects therein.

Aus der DE-A-16 28 245 ist eine Vakuumpumpe mit Luft- und Ölzuführung bekannt. Mit Hilfe aufwendiger mechanischer Mittel wird verhindert, daß beim Anhalten oder bei reduzierter Drehzahl des Rotors Luft in den Schöpfraum der Vakuumpumpe gelangt. Die Gefahr des Ölrückstiegs ist nicht beseitigt; eine Vakuumsicherung im Sinne der vorliegenden Erfindung - Aufrechterhaltung des Vakuums im an die Pumpe angeschlossenen Rezipienten und Verhinderung einer Ölverseuchung des Rezipienten bei Ausfall oder reduzierter Drehzahl der Pumpe - wird nicht erreicht.From DE-A-16 28 245 a vacuum pump with air and oil supply is known. With the help of complex mechanical means, air is prevented from entering the vacuum pump's pump chamber when the rotor is stopped or at a reduced speed. The risk of oil return has not been eliminated; a vacuum protection in the sense of the present invention - maintaining the vacuum in the recipient connected to the pump and preventing oil contamination of the recipient in the event of failure or reduced speed of the pump - is not achieved.

Aus der DE-A-40 16 015 ist eine Vakuumpumpe mit einem Ölkanal bekannt, der zum Teil Bestandteil des Rotors selbst ist. Im Bereich des Rotors ist der Ölkanal mit einem fliehkraftbetätigten Ventil ausgerüstet, das bei Stillstand ein Ansaugen von Öl in den Schöpfraum der Pumpe verhindern soll. Ein Ansaugen von Luft in den Rezipienten wird jedoch nicht verhindert; eine Vakuumsicherung wird ebenfalls nicht erreicht.From DE-A-40 16 015 a vacuum pump with an oil channel is known, which is part of the rotor itself. In the area of the rotor, the oil channel is equipped with a centrifugal valve that is designed to prevent oil from being sucked into the pump's pump chamber when it is at a standstill. An intake of air in the recipient is not prevented; vacuum protection is also not achieved.

Der vorliegenden Erfindung liegt die Aufgabe zugrunde, eine Vakuumpumpe der eingangs erwähnten Art derart zu betreiben, daß eine Vakuumsicherung nicht nur bei Stromausfall gewährleistet ist.The present invention has for its object to operate a vacuum pump of the type mentioned in such a way that vacuum protection is not only guaranteed in the event of a power failure.

Erfindungsgemäß wird diese Aufgabe durch die kennzeichnenden Merkmale des Patentanspruchs 1 gelöst. Ein in dieser Weise gesteuertes Ölzuführungsventil schließt also nicht nur bei Stromausfall oder Stromabschaltung sondern auch bei einem Stop der Pumpe auf Grund eines mechanischen Defektes. Die Aufrechterhaltung des Vakuums im Rezipienten ist damit auch bei einem mechanischen Defekt sichergestellt; die Gefahr der beschriebenen Ölverseuchungen im Rezipienten ist beseitigt.According to the invention, this object is achieved by the characterizing features of patent claim 1. An oil supply valve controlled in this way therefore closes not only in the event of a power failure or power cut-off, but also in the event of one Stop of the pump due to a mechanical defect. The maintenance of the vacuum in the recipient is thus ensured even in the event of a mechanical defect; the risk of the oil contamination described in the recipient has been eliminated.

Weitere Vorteile und Einzelheiten sollen anhand der Figuren 1 und 2 erläutert werden. Es zeigen

Figur 1
einen stark vereinfachten Schnitt durch eine Drehschiebervakuumpumpe und
Figur 2
ein Funktionsschaltbild.
Further advantages and details will be explained with reference to Figures 1 and 2. Show it
Figure 1
a greatly simplified section through a rotary vane vacuum pump and
Figure 2
a functional diagram.

Die in Figur 1 dargestellte Drehschiebervakuumpumpe 1 weist ein Pumpengehäuse 2 mit einem Schöpfraum 3 auf. Im Schöpfraum 3 befindet sich der drehbar angeordnete Rotor 4, der die Drehschieber 5, 6 führt. Seitlich von der Rotoranlage 6 befinden sich der Einlaßstutzen 7 und der Auslaßstutzen 8. An den Einlaßstutzen 7 wird der zu evakuierende, nicht dargestellte Rezipient angeschlossen. Der Auslaßstutzen 8 ist mit dem Rückschlagventil 9 ausgerüstet, das den Auslaßstutzen 8 immer dann vakuumdicht verschließt, wenn die Pumpe keine Fluide fördert.The rotary vane vacuum pump 1 shown in FIG. 1 has a pump housing 2 with a pumping chamber 3. In the scoop 3 is the rotatably arranged rotor 4, which Rotary valve 5, 6 leads. The inlet connection 7 and the outlet connection 8 are located on the side of the rotor system 6. The recipient, not shown, to be evacuated is connected to the inlet connection 7. The outlet port 8 is equipped with the check valve 9, which always closes the outlet port 8 in a vacuum-tight manner when the pump does not deliver any fluids.

In den Schöpfraum 3 mündet noch die Ölzuführungsleitung 11, über die der Schöpfraum 3 ständig aus der schematisch dargestellten ölwanne 12 mit Öl versorgt wird. In die Leitung 11 ist das Magnetventil 13 eingeschaltet.The oil supply line 11 also opens into the scooping chamber 3, via which the scooping chamber 3 is continuously supplied with oil from the schematically illustrated oil pan 12. Solenoid valve 13 is switched on in line 11.

Der Rotor 4 ist mit einem in Figur 1 nicht dargestellten Antriebsmotor gekoppelt. Gleichzeitig mit dem An- und Abschalten des Antriebsmotors wird das Ventil 13 derart betätigt, daß es bei eingeschaltetem Strom offen ist. Bei abgeschaltetem Strom - also auch bei Stromausfall - ist das Ventil 13 geschlossen.The rotor 4 is coupled to a drive motor, not shown in FIG. 1. Simultaneously with the switching on and off of the drive motor, the valve 13 is actuated such that it is open when the current is switched on. When the power is switched off - also in the event of a power failure - the valve 13 is closed.

Bei dem in Figur 2 dargestellten Funktionsschaltbild für ein Ausführungsbeispiel nach der Erfindung sind schematisch wesentliche Bauelemente eines Einphasen-Kondensator-Motors 14 dargestellt, nämlich die Motorspule 15 (Hauptwicklung), der Motorkondensator 16 und die Motorspule 20 (Hilfswicklung). Die Spannungsversorgung erfolgt über die Leitungen 17, 18, die über den Schalter 19 an die Wechselspannungsquelle 21 angeschlossen sind. Zusätzlich ist noch schematisch ein Temperatursensor 22 dargestellt. Dieser dient in bekannter Weise dem Temperaturschutz des Motors 14. Übersteigt die Temperatur einen Grenzwert, dann erfolgt automatisch eine Abschaltung des Motors (angedeutet durch den Pfeil 23).In the functional circuit diagram shown in FIG. 2 for an exemplary embodiment according to the invention, essential components of a single-phase capacitor motor 14 are shown schematically, namely the motor coil 15 (main winding), the motor capacitor 16 and the motor coil 20 (auxiliary winding). The voltage supply takes place via the lines 17, 18, which are connected to the AC voltage source 21 via the switch 19. In addition, a temperature sensor 22 is also shown schematically. This is used in a known manner to protect the temperature of the motor 14. If the temperature exceeds a limit value, the motor is automatically switched off (indicated by arrow 23).

Auch das Ventil 13 ist über die Leitungen 24, 25 und den Schalter 19 an die Wechselspannungsquelle 21 angeschlossen. Im Falle des Stromabschaltens, eines Stromausfalles oder einer unzulässigen Motortemperatur erfolgt deshalb gleichzeitig mit dem Pumpenstop die Schließbewegung des Ventils 13.The valve 13 is also connected to the AC voltage source 21 via the lines 24, 25 and the switch 19. In the event of a power cut, a power failure or an impermissible motor temperature, the valve 13 is closed at the same time as the pump stops.

Als drehzahlabhängiger Sensor dient die in Reihe mit dem Motorkondesator geschaltete Spule 20, über der die von der Drehzahl n abhängige Spannung Un abfällt. Der Wert von Un nimmt seinen maximalen Wert bei der Lehrlaufdrehzahl des Motors an. Bei der Drehzahl 0 ist auch der Wert von Un klein.The coil 20, which is connected in series with the motor capacitor, serves as the speed-dependent sensor, via which the voltage U n , which is dependent on the speed n, drops. The value of U n takes its maximum value at the engine idling speed. At speed 0, the value of U n is also small.

Der Wert Un wird einer Logik 26 zugeführt, innerhalb der der Wert von Un ständig mit einem Soll- oder Grenzwert verglichen wird. Solange der Wert von Un größer ist als der Sollwert, wird ein Signal nicht weitergeleitet. Unterschreitet der Wert von Un den Sollwert, dann wird über die Leitung 27 ein Relais 28 mit dem Schalter 29 betätigt. Der Schalter 29 liegt in dem von den Leitungen 24, 25 gebildeten Stromkreis, in den auch das Ventil 13 eingeschaltet ist. Die Betätigung des Relais 28, 29 erfolgt in der Weise, daß mit dem Unterschreiten des mit Hilfe der Logik 26 überwachten Sollwertes der Schalter 29 geöffnet wird. Dieser Öffnungsvorgang hat zur Folge, daß das Magnetventil 13 schließt, und zwar auch dann, wenn Schalter 19 noch geschlossen bleibt. Dadurch ist sichergestellt, daß die Ölversorgung über die Zuleitung 11 auch dann gestoppt wird, wenn bei geschlossenem Schalter 19 ein mechanischer Defekt auftritt.The value U n is fed to a logic 26, within which the value of U n is continuously compared with a target or limit value. As long as the value of U n is greater than the setpoint, a signal is not forwarded. If the value of U n falls below the setpoint value, then a relay 28 with the switch 29 is actuated via the line 27. The switch 29 is located in the circuit formed by the lines 24, 25, in which the valve 13 is also switched on. The actuation of the relay 28, 29 takes place in such a way that the switch 29 is opened when the setpoint value monitored by the logic 26 is undershot. The result of this opening process is that the solenoid valve 13 closes, even when switch 19 remains closed. This ensures that the oil supply via the supply line 11 is also stopped if a mechanical defect occurs when the switch 19 is closed.

Bei einem zweckmäßigen Ausführungsbeispiel ist der Sollwert der Logik 26 derart gewählt, daß er dem Wert für Un bei 20 % der Lehrlaufdrehzahl des Antriebsmotors 14 entspricht. Tritt also zum Beispiel bei einer Vakuumpumpe mit einem Antriebsmotor, dessen Lehrlaufdrehzahl 1500 U/min beträgt, ein mechanischer Defekt auf, der die Drehzahl auf 300 U/min absinken läßt, dann öffnet sich der Schalter 29, so daß das Magnetventil 13 schließt, die Ölzufuhr zum Schöpfraum also unterbrochen ist. Die Aufrechterhaltung des Vakuums im angeschlossenen Rezipienten ist dadurch sichergestellt. Läuft die Pumpe wieder an, dann erfolgt automatisch wieder eine Öffnung des Schalters 29 und damit des Ventils 13.In an expedient embodiment, the setpoint value of the logic 26 is selected such that it corresponds to the value for U n at 20% of the idle speed of the drive motor 14. If, for example, a mechanical defect occurs in a vacuum pump with a drive motor whose idle speed is 1500 rpm, which causes the speed to drop to 300 rpm, then the switch 29 opens so that the solenoid valve 13 closes Oil supply to the pump chamber is therefore interrupted. This ensures that the vacuum in the connected recipient is maintained. If the pump starts again, the switch 29 and thus the valve 13 are automatically opened again.

Unmittelbar nach dem Auftreten eines mechanischen Defektes, der zu einem Anhalten der Pumpe oder zu einer sehr niedrigen Drehzahl des Rotors 4 führt, heizt sich der Antriebsmotor 14 auf. Nach kurzer Zeit wird deshalb der dem Antriebsmotor 14 zugeordnete Thermoschutz (22, 23) die Abschaltung des Stromes bewirken, so daß die Pumpe zum Stillstand kommt.Immediately after the occurrence of a mechanical defect, which leads to the pump stopping or to a very low speed of the rotor 4, the drive motor 14 heats up. After a short time, the drive motor 14 is assigned Thermal protection (22, 23) cause the current to be switched off so that the pump comes to a standstill.

Die Logik 26 und das Relais 28, 29 sind in einem Gehäuse 31 untergebracht. Sie enthalten - bis auf den Schalter 29 des Relais - keine mechanischen Teile, so daß die erfindungsgemäße Lösung zuverlässig ist und eine lange Lebensdauer hat. Außerdem hat die erfindungsgemäße Lösung den Vorteil, daß sie unabhängig vom Druck im Rezipienten arbeitet.The logic 26 and the relay 28, 29 are accommodated in a housing 31. They contain - apart from the switch 29 of the relay - no mechanical parts, so that the solution according to the invention is reliable and has a long service life. In addition, the solution according to the invention has the advantage that it works independently of the pressure in the recipient.

Anstelle eines Relais kann auch ein Halbleiterschalter vorgesehen sein, so daß mechanische Teile völlig entfallen. Weiterhin besteht die Möglichkeit, die Logik 26 und den Schalter 29 über eine optische Koppelstrecke miteinander zu verbinden. Schließlich besteht die Möglichkeit, ein Bauelement einzusetzen, das sowohl Logik- als auch Schaltfunktion hat. Derartige Leistungshalbleiter sind unter dem Namen "Smart-power"-Baustein an sich bekannt.Instead of a relay, a semiconductor switch can also be provided, so that mechanical parts are completely eliminated. It is also possible to connect the logic 26 and the switch 29 to one another via an optical coupling link. Finally, it is possible to use a component that has both a logic and a switching function. Power semiconductors of this type are known per se under the name “smart power” module.

Claims (8)

  1. Oil-sealed vacuum pump with
    - a pump casing (2),
    - a suction chamber (3) located within the pump casing,
    - a rotor (4) arranged rotatably within the suction chamber,
    - an inlet pipe (7) capable of being connected to a receiving vessel,
    - an outlet pipe (8) provided with a check valve (9),
    - an oil-supply line (11) passing into the suction chamber (3) and provided with a valve (13), and also
    - an electrical drive motor (14) for the rotor (4),
    characterised in that the drive motor (14) is provided with a speed-dependent sensor (20), in that the valve (13) is a valve which is capable of being actuated electrically and in that a switch (29) is provided in the electrical circuit (24, 25) of the valve (13) which, depending on the signals supplied by the sensor (20), is controlled in such a way that the valve (13) is open in the case of normal operating speed and closed in the case of reduced speed.
  2. Oil-sealed vacuum pump according to Claim 1, in which the drive pump (14) has a first motor coil (main winding 15), a second motor coil (auxiliary winding 20) and also a capacitor (16), characterised in that the auxiliary winding (20) forms the sensor by use being made of the voltage that drops via the coil (20) of the drive motor (14).
  3. Vacuum pump according to Claim 1 or 2, characterised in that a logic circuit (26) is provided with a view to evaluation of the signals of the sensor (20).
  4. Vacuum pump according to Claim 3, characterised in that the logic circuit (26) is connected to a switch (28, 29) via a signal line (27).
  5. Vacuum pump according to Claim 4, characterised in that the switch is a relay (28, 29).
  6. Vacuum pump according to Claim 4, characterised in that the switch is a semiconductor switch.
  7. Vacuum pump according to Claim 4, 5 or 6, characterised in that an optical coupling section is connected to the logic circuit (26) by way of signal line.
  8. Vacuum pump according to Claim 1 or 2, characterised in that with a view to evaluation of the signals of the sensor (20) a component is provided which has a logic function and a semiconductor-switch function.
EP93903938A 1992-03-14 1993-02-09 Oil-sealed vacuum pump Expired - Lifetime EP0630446B1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE4208194 1992-03-14
DE4208194A DE4208194A1 (en) 1992-03-14 1992-03-14 METHOD FOR OPERATING AN OIL-SEALED VACUUM PUMP AND A VACUUM PUMP SUITABLE FOR IMPLEMENTING THIS METHOD
PCT/EP1993/000312 WO1993019298A1 (en) 1992-03-14 1993-02-09 Method of operating an oil-sealed vacuum pump

Publications (2)

Publication Number Publication Date
EP0630446A1 EP0630446A1 (en) 1994-12-28
EP0630446B1 true EP0630446B1 (en) 1995-12-13

Family

ID=6454066

Family Applications (1)

Application Number Title Priority Date Filing Date
EP93903938A Expired - Lifetime EP0630446B1 (en) 1992-03-14 1993-02-09 Oil-sealed vacuum pump

Country Status (6)

Country Link
EP (1) EP0630446B1 (en)
JP (1) JPH07504730A (en)
KR (1) KR950701041A (en)
DE (2) DE4208194A1 (en)
ES (1) ES2081705T3 (en)
WO (1) WO1993019298A1 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102004024554B4 (en) * 2004-05-18 2018-01-25 Pfeiffer Vacuum Gmbh Oil-sealed rotary vane vacuum pump
DE102004034925B3 (en) * 2004-07-09 2006-02-16 Joma-Hydromechanic Gmbh A single-blade
GB0607198D0 (en) * 2006-04-10 2006-05-17 Wabco Automotive Uk Ltd Improved vacuum pump
DE112010002597A5 (en) * 2009-06-17 2012-10-11 Ixetic Hückeswagen Gmbh OIL PRESSURE VALVE FOR A VACUUM PUMP

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1190134B (en) * 1957-02-07 1965-04-01 Edwards High Vacuum Ltd Rotary piston vacuum pump with oil-superimposed exhaust valve
FR1450639A (en) * 1965-06-30 1966-06-24 Beaudouin Sa Ets Improvements to mechanical oil injection and air injection vacuum pumps
GB1241944A (en) * 1967-06-10 1971-08-04 N G N Ltd Improvements in and relating to rotary vacuum pumps
GB1179664A (en) * 1968-03-18 1970-01-28 Donald Richard Angliss Improvements in or relating to Rotary Vacuum Pumps
FR2383335A1 (en) * 1977-03-08 1978-10-06 Leybold Heraeus Sogev MECHANICAL PUMP WITH OIL SEAL
DE4016015C2 (en) * 1989-06-01 1998-01-29 Barmag Barmer Maschf Vane vacuum pump

Also Published As

Publication number Publication date
ES2081705T3 (en) 1996-03-16
DE59301174D1 (en) 1996-01-25
EP0630446A1 (en) 1994-12-28
WO1993019298A1 (en) 1993-09-30
DE4208194A1 (en) 1993-09-16
KR950701041A (en) 1995-02-20
JPH07504730A (en) 1995-05-25

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