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EP0205954B1 - Positive-displacement machine - Google Patents

Positive-displacement machine Download PDF

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Publication number
EP0205954B1
EP0205954B1 EP86107036A EP86107036A EP0205954B1 EP 0205954 B1 EP0205954 B1 EP 0205954B1 EP 86107036 A EP86107036 A EP 86107036A EP 86107036 A EP86107036 A EP 86107036A EP 0205954 B1 EP0205954 B1 EP 0205954B1
Authority
EP
European Patent Office
Prior art keywords
gear pump
bore
gear
flow
connection
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
Application number
EP86107036A
Other languages
German (de)
French (fr)
Other versions
EP0205954A1 (en
Inventor
Claus Dipl.-Ing. Jöns
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.)
Robert Bosch GmbH
Original Assignee
Robert Bosch 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 Robert Bosch GmbH filed Critical Robert Bosch GmbH
Publication of EP0205954A1 publication Critical patent/EP0205954A1/en
Application granted granted Critical
Publication of EP0205954B1 publication Critical patent/EP0205954B1/en
Expired legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C14/00—Control of, monitoring of, or safety arrangements for, machines, pumps or pumping installations
    • F04C14/02—Control of, monitoring of, or safety arrangements for, machines, pumps or pumping installations specially adapted for several machines or pumps connected in series or in parallel

Definitions

  • the invention is based on a displacement machine according to the preamble of claim 1.
  • a displacement machine is known from US-A-3 442 218.
  • the connecting channel is designed as a complex and relatively expensive housing bore.
  • Such holes have to be aligned relatively precisely, which is associated with high workload and costs.
  • the displacement machine according to the invention with the characterizing features of the main claim has the advantage that even a curved course of the connection is possible without the need for complicated manufacturing processes.
  • the displacement machine 10 consists of two gear pumps 11, 12 with housings 13, 14 flanged to one another.
  • the housing 13 of the gear pump 11 is closed on both ends by housing covers 15, 16. It has a continuous recess 17 in which the gears 18, 18a of the gear pump 11 are arranged.
  • the shaft journals of the gear wheels 18, 18a of the gear pump 11 are mounted in bearing bodies 21, 21a, 22, 22a.
  • an inlet bore 23, which leads to the low pressure region 24 of the gear pump 11, and an outlet bore 25, which connects the high pressure region 26 to a consumer A, not shown, are formed in the housing 13, an inlet bore 23, which leads to the low pressure region 24 of the gear pump 11, and an outlet bore 25, which connects the high pressure region 26 to a consumer A, not shown, are formed.
  • the gear pump 12 is designed.
  • the housing 14 is closed on its end face facing the housing 13 by an end plate 27.
  • the housing 28 of a flow control valve 29 is arranged on the other end face.
  • the housing 14 of the gear pump 12 also has a continuous recess 31 in which the gears 32, 32a are arranged.
  • the shaft journals of the gear pump 12 are mounted in bearing bodies 34, 34a, 35, 35a, which are also arranged in the recess 31.
  • the gear 18 of the gear pump 11 has a drive shaft 36, which penetrates to the outside in a sealed manner through a bore in the housing cover 15 and is used to drive both gear pumps 11 and 12. It is possible to design both gear pumps 11, 12 of the same size or with different delivery rates.
  • a bore 38, 39 is formed in each of the flanged housing cover 16 and in the end plate 27, via which the low-pressure area 24 of the gear pump 11 is connected to the low-pressure area 40 of the gear pump 12. Furthermore, there is a second bore 41, 42 in the end plate 27 and in the housing cover 16, which are connected to one another.
  • the bore 41 opens into the high-pressure region 26 of the pump 11.
  • a check valve 43 which is open towards the high-pressure region 26 is arranged in it.
  • a longitudinal bore 45 is formed in the housing 28 of the flow control valve 29 and is closed at both ends by locking screws 46, 47.
  • Three ring grooves 48, 49, 50 are arranged in it, the ring grooves 48, 50 serving as drainage chambers.
  • the annular groove 48 is connected via a bore 51 to a consumer B, not shown.
  • a tubular channel 52 leads from the annular groove 50 to the bore 42.
  • the channel 52 runs through the pressure chamber of the pump 12 and has pipe plug connections at its ends.
  • a control slide 53 is slidably guided in the longitudinal bore 45. It has a blind bore 54 which is the same axis as the longitudinal bore 45 and which is cut in the bottom 55 of a bore 56 extending transversely to the blind bore 54. At the end of the control slide 53 facing away from the opening of the blind bore 54, there is the end of a control spring 57, the other end of which rests on the end plug 46.
  • a measuring orifice 58 is arranged in the opening of the blind bore 54. The space between the orifice plate 58 and the end screw 47 serves as the pressure chamber 59.
  • the pressure chamber 59 is connected to the high-pressure region 61 of the gear pump 12 via a bore 60.
  • the gear pumps 11, 12 suck in pressure medium via the inlet bore 23, then this flows into the low pressure region 24 of the gear pump 11 and via the bores 38, 39 also into the low pressure region 40 of the gear pump 12.
  • the gear pump 12 is to be kept constant with the help of the flow control valve 29 Deliver output to a consumer.
  • the pressure medium flows from the high pressure region 61 of the gear pump 1 via the bore 60 into the pressure chamber 59 of the longitudinal bore 45. From there it flows through the measuring orifice 58 into the blind bore 54 and through the bore 56 into the annular groove 48 and to the consumer.
  • the dynamic pressure which arises at the orifice plate 58 displaces the control slide 53 against the force of the regulator spring 57, so that the connection from the pressure chamber 59 to the annular groove 50 is opened, while the connection from the bore 56 to the annular groove 48 becomes smaller and smaller.
  • the length of the control slide 53 is adjusted so that the connection from the pressure chamber 59 to the annular groove 50 is completely open, on the other hand, the connection from the bore 56 to the annular groove 48 is almost completely closed.
  • the delivery flow flowing to the consumer thus always has a constant value which is regulated by the flow control valve 29.
  • the excess pressure medium flowing into the annular groove 50 flows via the line 52, the bores 42, 41 and the check valve 43 into the high-pressure region 26 of the gear pump 11.
  • This quantity of pressure medium is added to the delivery flow conveyed by the gear pump 11.
  • the check valve 43 prevents a pressure medium flow from the high-pressure region 26 of the gear machine 11 to the flow control valve 29, as a result of which its control level is not influenced. So thus after the constant flow rate determined by the flow control valve 29 has been reached, the pressure medium excessly delivered by the gear pump 12 is additionally added to the flow rate of the gear pump 11. This makes it possible to design the gear pump 11 to be smaller than the desired delivery quantity, because the excess pressure medium of the gear pump 12 is still available.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Details And Applications Of Rotary Liquid Pumps (AREA)
  • Rotary Pumps (AREA)

Description

Stand der TechnikState of the art

Die Erfindung geht aus von einer Verdrängermaschine nach dem Oberbegriff von Anspruch 1. Eine solche Maschine ist bekannt aus der Druckschrift US-A-3 442 218. Nach dieser Druckschrift ist der Verbindungskanal als eine aufwendige und relativ teure Gehäusebohrung ausgebildet. Solche Bohrungen müssen relativ genau fluchten, was mit hohem Arbeitsaufwand und Kosten verbunden ist.The invention is based on a displacement machine according to the preamble of claim 1. Such a machine is known from US-A-3 442 218. According to this publication, the connecting channel is designed as a complex and relatively expensive housing bore. Such holes have to be aligned relatively precisely, which is associated with high workload and costs.

Vorteile der ErfindungAdvantages of the invention

Die erfindungsgemäße Verdrängermaschine mit den kennzeichnenden Merkmalen des Hauptanspruchs hat demgegenüber den Vorteil, daß sogar ein gebogener Verlauf der Verbindung möglich ist, ohne daß komplizierte Herstellungsverfahren notwendig sind.The displacement machine according to the invention with the characterizing features of the main claim has the advantage that even a curved course of the connection is possible without the need for complicated manufacturing processes.

Zeichnungdrawing

Ein Ausführungsbeispiel der Erfindung ist in der Zeichnung dargestellt und in der nachfolgenden Beschreibung näher erläutert. Die einzige Figur zeigt einen Längsschnitt durch eine Verdrängermaschine.An embodiment of the invention is shown in the drawing and explained in more detail in the following description. The single figure shows a longitudinal section through a displacement machine.

Beschreibung des AusführungsbeispielsDescription of the embodiment

Die Verdrängermaschine 10 besteht aus zwei Zahnradpumpen 11,12 mit aneinander angeflanschten Gehäusen 13, 14. Das Gehäuse 13 der Zahnradpumpe 11 ist an beiden Stirnseiten durch Gehäusedeckel 15, 16 abgeschlossen. Es hat eine durchgehende Ausnehmung 17, in der die Zahnräder 18, 18a der Zahnradpumpe 11 angeordnet sind. Die Wellenzapfen der Zahnräder 18, 18a der Zahnradpumpe 11 sind in Lagerkörpern 21, 21a, 22, 22a gelagert. Im Gehäuse 13 sind eine Zulaufbohrung 23, die zum Niederdruckbereich 24 der Zahnradpumpe 11 führt, und eine Auslaßbohrung 25, die den Hochdruckbereich 26 zu einem nicht dargestellten Verbraucher A hin verbindet, ausgebildet.The displacement machine 10 consists of two gear pumps 11, 12 with housings 13, 14 flanged to one another. The housing 13 of the gear pump 11 is closed on both ends by housing covers 15, 16. It has a continuous recess 17 in which the gears 18, 18a of the gear pump 11 are arranged. The shaft journals of the gear wheels 18, 18a of the gear pump 11 are mounted in bearing bodies 21, 21a, 22, 22a. In the housing 13, an inlet bore 23, which leads to the low pressure region 24 of the gear pump 11, and an outlet bore 25, which connects the high pressure region 26 to a consumer A, not shown, are formed.

Genauso wie die Zahnradpumpe 11 ist die Zahnradpumpe 12 ausgebildet. Das Gehäuse 14 ist an seiner dem Gehäuse 13 zugewandten Stirnseite von einer Abschlußplatte 27 abgeschlossen. An der anderen Stirnseite ist das Gehäuse 28 eines Stromregelventils 29 angeordnet. Das Gehäuse 14 der Zahnradpumpe 12 hat ebenfalls eine durchgehende Ausnehmung 31, in der die Zahnräder 32, 32a angeordnet sind. Die Wellenzapfen der Zahnradpumpe 12 sind in Lagerkörpern 34, 34a, 35, 35a gelagert, die ebenfalls in der Ausnehmung 31 angeordnet sind.Just like the gear pump 11, the gear pump 12 is designed. The housing 14 is closed on its end face facing the housing 13 by an end plate 27. The housing 28 of a flow control valve 29 is arranged on the other end face. The housing 14 of the gear pump 12 also has a continuous recess 31 in which the gears 32, 32a are arranged. The shaft journals of the gear pump 12 are mounted in bearing bodies 34, 34a, 35, 35a, which are also arranged in the recess 31.

Das Zahnrad 18 der Zahnradpumpe 11 hat eine Antriebswelle 36, die durch eine Bohrung im Gehäusedeckel 15 abgedichtet nach außen dringt und zum Antrieb beider Zahnradpumpen 11 und 12 dient. Es ist möglich, beide Zahnradpumpen 11, 12 gleich groß oder mit unterschiedlicher Förderleistung auszubilden.The gear 18 of the gear pump 11 has a drive shaft 36, which penetrates to the outside in a sealed manner through a bore in the housing cover 15 and is used to drive both gear pumps 11 and 12. It is possible to design both gear pumps 11, 12 of the same size or with different delivery rates.

In dem angeflanschten Gehäusedeckel 16 und in der Abschlußplatte 27 ist je eine Bohrung 38, 39 ausgebildet, über die der Niederdruckbereich 24 der Zahnradpumpe 11 mit dem Niederdruckbereich 40 derZahnradpumpe 12 verbunden ist. Ferner befindet sich in der Abschlußplatte 27 und im Gehäusedeckel 16 je eine zweite Bohrung 41, 42, die miteinander verbunden sind. Die Bohrung 41 mündet in den Hochdruckbereich 26 der Pumpe 11. In ihr ist ein zum Hochdruckbereich 26 hin geöffnetes Rückschlagventil 43 angeordnet.A bore 38, 39 is formed in each of the flanged housing cover 16 and in the end plate 27, via which the low-pressure area 24 of the gear pump 11 is connected to the low-pressure area 40 of the gear pump 12. Furthermore, there is a second bore 41, 42 in the end plate 27 and in the housing cover 16, which are connected to one another. The bore 41 opens into the high-pressure region 26 of the pump 11. A check valve 43 which is open towards the high-pressure region 26 is arranged in it.

Im Gehäuse 28 des Stromregelventils 29 ist eine Längsbohrung 45 ausgebildet, die an beiden Enden von Verschlußschrauben 46, 47 verschlossen ist. In ihr sind drei Ringnuten 48, 49, 50 angeordnet, wobei die Ringnuten 48, 50 ats Abiaufkammern dienen. Die Ringnut 48 steht über eine Bohrung 51 mit einem nicht dargestellten Verbraucher B in Verbindung. Von der Ringnut 50 führt ein rohrförmiger Kanal 52 zur Bohrung 42. Der Kanal 52 verläuft durch den Druckraum der Pumpe 12 und hat an seinen Enden Rohrsteckverbindungen.A longitudinal bore 45 is formed in the housing 28 of the flow control valve 29 and is closed at both ends by locking screws 46, 47. Three ring grooves 48, 49, 50 are arranged in it, the ring grooves 48, 50 serving as drainage chambers. The annular groove 48 is connected via a bore 51 to a consumer B, not shown. A tubular channel 52 leads from the annular groove 50 to the bore 42. The channel 52 runs through the pressure chamber of the pump 12 and has pipe plug connections at its ends.

In der Längsbohrung 45 ist ein Steuerschieber 53 gleitend geführt. Er weist eine zur Längsbohrung 45 achsgleiche Sackbohrung 54 auf, die im Bohrungsgrund 55 von einer quer zur Sackbohrung 54 verlaufenden Bohrung 56 geschnitten wird. An der der Öffnung der Sackbohrung 54 abgewandten Stirnseite des Steuerschiebers 53 liegt das Ende einer Reglerfeder 57 an, deren anderes Ende sich an den Abschlußstopfen 46 anlegt. In der Öffnung der Sackbohrung 54isteine Meßblende 58 angeordnet. Der Raum zwischen Meßblende 58 und Abschlußschraube 47 dient als Druckraum 59. Über eine Bohrung 60 ist der Druckraum 59 mit dem Hochdruckbereich 61 der Zahnradpumpe 12 verbunden.A control slide 53 is slidably guided in the longitudinal bore 45. It has a blind bore 54 which is the same axis as the longitudinal bore 45 and which is cut in the bottom 55 of a bore 56 extending transversely to the blind bore 54. At the end of the control slide 53 facing away from the opening of the blind bore 54, there is the end of a control spring 57, the other end of which rests on the end plug 46. A measuring orifice 58 is arranged in the opening of the blind bore 54. The space between the orifice plate 58 and the end screw 47 serves as the pressure chamber 59. The pressure chamber 59 is connected to the high-pressure region 61 of the gear pump 12 via a bore 60.

Saugen die Zahnradpumpen 11, 12 Druckmittel über die Zulaufbohrung 23 an, so strömt dieses in den Niederdruckbereich 24 der Zahnradpumpe 11 und über die Bohrungen 38, 39 auch in den Niederdruckbereich 40 der Zahnradpumpe 12. Die Zahnradpumpe 12 soll mit Hilfe des Stromregelventils 29 eine konstante Fördermenge zu einem Verbraucher liefern. Dazu strömt das Druckmittel vom Hochdruckbereich 61 der Zahnradpumpe 1 über die Bohrung 60 in den Druckraum 59 der Längsbohrung 45. Von dort fließt es durch die Meßblende 58 in die Sackbohrung 54 und über die Bohrung 56 in die Ringnut 48 und zum Verbraucher. Der an der Meßblende 58 entstehende Staudruck verschiebt den Steuerschieber 53 gegen die Kraft der Reglerfeder 57, so daß die Verbindung vom Druckraum 59 zur Ringnut 50 geöffnet wird, während die Verbindung von der Bohrung 56 zur Ringnut 48 immer kleiner wird. Die Länge des Steuerschiebers 53 ist dabei so abgestimmt, daß die Verbindung vom Druckraum 59 zur Ringnut 50 völlig geöffnet ist, wenn andererseits die Verbindung von der Bohrung 56 zur Ringnut 48 fast völlig geschlossen ist. Somit weist der zum Verbraucher strömende Förderstrom immer einen konstanten Wert auf, der durch das Stromregelventil 29 geregelt wird. Das in die Ringnut 50 strömende überschüssige Druckmittel fließt über die Leitung 52, die Bohrungen 42, 41 und das Rückschlagventil 43 in den Hochdruckbereich 26 der Zahnradpumpe 11. Diese Druckmittelmenge wird dem von der Zahnradpumpe 11 geförderten Förderstrom hinzuaddiert. Das Rückschlagventil 43 verhindert einen Druckmittelfluß vom Hochdruckbereich 26 der Zahnradmaschine 11 zum Stromregelventil 29, wodurch dessen Regelniveau nicht beeinflußt wird. Somit wird also nach Erreichen des durch das Stromregelventil 29 bestimmten konstanten Förderstroms das von der Zahnradpumpe 12 überschüssig geförderte Druckmittel zusätzlich noch dem Förderstrom der Zahnradpumpe 11 hinzuaddiert. Dadurch ist es möglich, die Zahnradpumpe 11 kleiner als für die gewünschte Fördermenge auszulegen, weil das überschüssige Druckmittel der Zahnradpumpe 12 noch zur Verfügung steht.If the gear pumps 11, 12 suck in pressure medium via the inlet bore 23, then this flows into the low pressure region 24 of the gear pump 11 and via the bores 38, 39 also into the low pressure region 40 of the gear pump 12. The gear pump 12 is to be kept constant with the help of the flow control valve 29 Deliver output to a consumer. For this purpose, the pressure medium flows from the high pressure region 61 of the gear pump 1 via the bore 60 into the pressure chamber 59 of the longitudinal bore 45. From there it flows through the measuring orifice 58 into the blind bore 54 and through the bore 56 into the annular groove 48 and to the consumer. The dynamic pressure which arises at the orifice plate 58 displaces the control slide 53 against the force of the regulator spring 57, so that the connection from the pressure chamber 59 to the annular groove 50 is opened, while the connection from the bore 56 to the annular groove 48 becomes smaller and smaller. The length of the control slide 53 is adjusted so that the connection from the pressure chamber 59 to the annular groove 50 is completely open, on the other hand, the connection from the bore 56 to the annular groove 48 is almost completely closed. The delivery flow flowing to the consumer thus always has a constant value which is regulated by the flow control valve 29. The excess pressure medium flowing into the annular groove 50 flows via the line 52, the bores 42, 41 and the check valve 43 into the high-pressure region 26 of the gear pump 11. This quantity of pressure medium is added to the delivery flow conveyed by the gear pump 11. The check valve 43 prevents a pressure medium flow from the high-pressure region 26 of the gear machine 11 to the flow control valve 29, as a result of which its control level is not influenced. So thus after the constant flow rate determined by the flow control valve 29 has been reached, the pressure medium excessly delivered by the gear pump 12 is additionally added to the flow rate of the gear pump 11. This makes it possible to design the gear pump 11 to be smaller than the desired delivery quantity, because the excess pressure medium of the gear pump 12 is still available.

Claims (2)

1. Positive-displacement machine (10), comprising at least two gear pumps (11, 12), with which an individual or common hydraulic circuit is associated and which deliver pressurized medium each to an individual consumer (A, B), the capacity of at least one gear pump (12) being regulated by means of a flow regulatorvalve (29) and its surplus residual flow being passed through a connecting duct (52) to the high-pressure side (26) of one of the other gear pumps (11), characterized in that the machine consists of mutually axially aligned components and that the connection (52) is constructed as a pipe ending in plug and socket connections and is passed through the pressure chamber of at least one gear pump (12).
2. Machine according to Claim 1, characterized in that a nonreturn valve (43) which shuts off towards the flow regulator valve (29) is arranged in the connection (52).
EP86107036A 1985-06-18 1986-05-23 Positive-displacement machine Expired EP0205954B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE8517637U 1985-06-18
DE8517637U DE8517637U1 (en) 1985-06-18 1985-06-18 Displacement machine

Publications (2)

Publication Number Publication Date
EP0205954A1 EP0205954A1 (en) 1986-12-30
EP0205954B1 true EP0205954B1 (en) 1989-12-20

Family

ID=6782221

Family Applications (1)

Application Number Title Priority Date Filing Date
EP86107036A Expired EP0205954B1 (en) 1985-06-18 1986-05-23 Positive-displacement machine

Country Status (2)

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EP (1) EP0205954B1 (en)
DE (2) DE8517637U1 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5017098A (en) * 1989-03-03 1991-05-21 Vickers, Incorporated Power transmission
DE19622518A1 (en) * 1996-06-05 1997-12-11 Eckerle Rexroth Gmbh Co Kg Double hydraulic pump assembly
DE19915319C2 (en) * 1998-09-02 2002-06-13 Eckerle Ind Elektronik Gmbh Double gear pump
GB2367095A (en) * 2000-09-13 2002-03-27 Sauer Danfoss Valve arrangement in separating plate of multiple hydraulic pump and motor ass emblies

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2533320A (en) * 1949-01-04 1950-12-12 Du Pont Rotary gear-type metering pump
US3402891A (en) * 1965-08-20 1968-09-24 Trw Inc Furnace pump and oil burner circuit
US3442218A (en) * 1966-04-12 1969-05-06 Gen Electric Dual purpose pump
DE2608980A1 (en) * 1976-03-04 1977-09-08 Rickmeier Pumpen Gear pump built up of several units - has offset pairs of gears to give pulse free flow
US4204811A (en) * 1977-08-19 1980-05-27 The Garrett Corporation Fluid pumping system
JPS58180790A (en) * 1982-04-19 1983-10-22 Jidosha Kiki Co Ltd Oil pump

Also Published As

Publication number Publication date
EP0205954A1 (en) 1986-12-30
DE3667709D1 (en) 1990-01-25
DE8517637U1 (en) 1986-10-16

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