US20050214149A1 - Displacement pump with variable volume flow - Google Patents

Displacement pump with variable volume flow Download PDF

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Publication number
US20050214149A1
US20050214149A1 US11/081,170 US8117005A US2005214149A1 US 20050214149 A1 US20050214149 A1 US 20050214149A1 US 8117005 A US8117005 A US 8117005A US 2005214149 A1 US2005214149 A1 US 2005214149A1
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United States
Prior art keywords
displacement pump
set forth
adjusting device
casing
ring
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.)
Abandoned
Application number
US11/081,170
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English (en)
Inventor
Hermonn Harle
Siegfried Eisenmann
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Individual
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Individual
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Publication of US20050214149A1 publication Critical patent/US20050214149A1/en
Abandoned legal-status Critical Current

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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04CROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C14/00Control of, monitoring of, or safety arrangements for, machines, pumps or pumping installations
    • F04C14/10Control of, monitoring of, or safety arrangements for, machines, pumps or pumping installations characterised by changing the positions of the inlet or outlet openings with respect to the working chamber
    • F04C14/14Control of, monitoring of, or safety arrangements for, machines, pumps or pumping installations characterised by changing the positions of the inlet or outlet openings with respect to the working chamber using rotating valves
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04CROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2/00Rotary-piston machines or pumps
    • F04C2/08Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
    • F04C2/10Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of internal-axis type with the outer member having more teeth or tooth-equivalents, e.g. rollers, than the inner member

Definitions

  • the invention relates to displacement pumps, in particular internal-axle gear pumps, but also wing cell pumps or for example also pendulum slider pumps, whose volume flow can be varied according to requirement, i.e. can be adjusted.
  • the pumps in accordance with the invention are preferably used as lubricant oil pumps for internal combustion engines, wherein the internal combustion engine itself preferably drives the lubricant oil pump in question.
  • the internal combustion engine can in particular be a drive motor, preferably a piston motor, of a vehicle.
  • the specific volume flow i.e. the volume flow delivered per revolution of a delivery wheel of the pump, can preferably be adjusted continuously.
  • the displacement pumps can also be advantageously used as supply pumps for automatic transmissions in vehicles and when used in this way are also preferably driven by the drive motor of the vehicle in question.
  • the displacement pump of the invention which can be adjusted according to requirement, is suitable in particular for such applications, in which with increasing drive speed, the fluid requirement increasingly falls short of the delivery volume of pumps whose specific delivery volume is constant
  • a pump in accordance with the invention can also be advantageously employed in other situations, in which for example the drive speed of the pump is constant and the fluid requirement of the aggregate to be supplied fluctuates for other reasons.
  • Displacement pumps formed as gear ring pumps such as the invention also relates to in particular, are known from DE 297 03 369 U1 and EP 0 846 861 B1 which is based on it.
  • the external rotor of the gear ring running set is rotatably mounted in a variable ring which surrounds the external rotor and rolls off without slipping in the pump casing via an internal-external toothing, such that in accordance with these kinematic ratios, the eccentric axis of the gear ring running set rotates by up to 90° relative to the casing during the varying process.
  • This enables a delivery amount to be varied from a maximum to almost zero, with as small an adjusting path as possible.
  • the displacement pump with variable volume flow in accordance with the invention comprises a casing and a chamber which is formed in the casing and comprises an inlet opening on a low pressure side and an outlet opening on a high pressure side for a fluid.
  • the pump can for example be an internal gear pump, a wing cell pump or a pendulum slider pump.
  • the pump further comprises an internal rotor which is accommodated in the chamber and can be rotated about a rotational axis, and a ring which is accommodated in the chamber and has a central ring axis which surrounds the internal rotor.
  • the ring and the internal rotor form at least one delivery cell in which the fluid is delivered from the low pressure side to the high pressure side.
  • An adjusting device is arranged such that during an adjusting movement, it rolls off on the casing without slipping.
  • the internal rotor is fixed to the adjusting device such that it can be rotated about the rotational axis. Furthermore, the position of the rotational axis relative to the ring axis of the ring can be adjusted by the adjusting movement of the adjusting device.
  • the outer ring forms an external rotor.
  • driving the gear ring running set formed by the internal rotor and the external rotor via the external rotor is facilitated.
  • the pump speed in the case of rotary driving via the external rotor is advantageously increased in accordance with the ratio of the numbers of teeth of the internal rotor and the external rotor, hence the diameter of the pump can be reduced.
  • the outer ring is also a rotor in a pendulum slider pump, such as is for example described in FR 980 766 .
  • the outer ring can be fixed relative to the casing, or the casing itself can form the internal cylindrical surface for a wing wheel forming the internal rotor.
  • an adjusting device which adjusts the specific volume flow does not surround the internal rotor and the outer ring but is arranged axially adjacent to them. It is particularly advantageous if arranging the adjusting device adjacent to the internal rotor and/or the outer ring is combined with adjusting the specific volume flow by adjusting the internal rotor.
  • the adjusting device preferably rotationally mounts the internal rotor such that it slaves the internal rotor during its own adjusting movement by being fixedly connected to the internal rotor with respect to the adjusting movement.
  • the adjusting device can for example comprise a toothing which is in toothed engagement with a toothing of the casing during an adjusting movement.
  • the toothing of the adjusting device is preferably a round-flank toothing. A centre point of a flank circle of a tooth of the toothing of the adjusting device can for example approximately describe a hypocycloid when rolling off on the casing.
  • variable pump By omitting the variable ring around the external rotor and by increasing the speed of the internal rotor in proportion to the numbers of teeth from the external rotor to the internal rotor as compared to the drive speed, the design space of the variable pump required is reduced superproportionally, for the same specific delivery amount.
  • variable pump in accordance with the invention is thus also suitable for small-volume internal combustion engines, in which particular value is placed on reducing the hydrostatic losses and the circulated amount of oil at high speeds.
  • the compactness of a variable displacement pump in accordance with the invention can hardly be surpassed. Since the shaft bearings are rid of any hydrostatic load, and are only then loaded by the traction rod of a continuously variable transmission such as is preferably used for driving, the diameter of the shaft can be reduced.
  • the smaller effective running set width also improves the suction capacity and reduces the danger of cavitation.
  • the volumetric efficiency is also improved due to the augmented high-speed running. This is also due to the fact that the pinion engagement between the external rotor and the internal rotor then trails at the point of maximum toothed engagement, such that the pressure side of the toothing is sealed better than the suction side.
  • the adjusting device adjusts hydraulically by being charged with a fluid pressure which is fed back from the high pressure side of the pump to the adjusting device.
  • the high pressure side of the pump reaches from the high pressure side of the pump chamber to the point or points of the aggregate or number of aggregates to be supplied, from which the fluid, relieved of pressure, is fed back to a fluid reservoir.
  • the pressure can for example be tapped at a crankshaft main gallery of the motor.
  • the fluid pressure acting in the pump chamber on the high pressure side in combination with the fluid pressure fed back to the adjusting device, generates the adjusting force for adjusting.
  • the adjusting force can for example be formed from at least one of the two hydraulic adjusting forces which act on the adjusting device and/or internal rotor.
  • the adjusting device can be adjusted by an adjusting force against the force of an elastic component.
  • the two adjusting forces are advantageously superimposed positively on each other, preferably by generating adjusting moments in the same direction. In this way, it is possible to achieve a varying which reacts particularly sensitively to changes in pressure.
  • the invention thus also relates to a displacement pump with variable volume flow, comprising the features of the preamble of at least one of the independent claims in combination with feeding the fluid pressure back to the adjusting device and charging the adjusting device with the fluid pressure fed back, in a direction such that the adjusting force thus generated is superimposed positively on an adjusting force generated by the fluid pressure of the high pressure side of the pump chamber acting on one of the internal rotor and the outer ring, the sum of the two forces being greater than each of the two individual forces.
  • such an embodiment gives rise to the advantage that the hydraulic adjusting forces of the internal rotor are added, over its bearing journal on the one hand and those between the adjusting device—preferably formed as an adjusting plate—and the casing, and not subtracted as with the known displacement pump.
  • This advantage is very important, particularly for cold starts in which a quick adjustment to a zero delivery amount is necessary in order to prevent damage to the oil filter and oil conduits. Up until now, it has been necessary here to provide an additional pressure control valve due to the inertia of the adjustment to zero.
  • this embodiment is preferably combined with adjusting the internal rotor or arranging the adjusting device axially adjacent to the internal rotor and/or the outer ring, and particularly preferably combined with both these features.
  • a round-flank toothing is most suitable on the adjusting plate, such that the internal toothing in the casing—which preferably comprises one tooth more than the external toothing of the adjusting plate—can be machined using a rotating cutting tool (drill rod), as is known from the known variable pump comprising a variable ring in FIG. 10 of EP 0 846 861 B1.
  • the centre point of the flank circle of the tooth on the adjusting plate describes a hypocycloid when rolling off in the casing, although in practice the hypocycloid is not entirely free of overlap.
  • a radial elevation stroke therefore arises during rolling off, such that the eccentricity of the variable plate in the casing therefore fluctuates.
  • the magnitude and/or the rotational angular position of an eccentricity between the rotational axis of the internal rotor and the central ring axis of the ring can for example be adjusted by the adjusting movement.
  • a fluctuation in the eccentricity can, however, be undesirable in the pump running set, since it leads to noise and wear on the pump toothing.
  • Guiding cylinders or cylinder segments which roll off on each other are therefore preferably provided on the adjusting plate and on the casing (in the drawings, on the pump casing in this case), having diameters whose difference is equal to twice the eccentricity of the pump running set, Therefore, the adjusting plate does not roll off in the coarse systematic toothing but on the two exactly machined circular cylinders.
  • the difference in the diameters of these guiding cylinders is equal to 2e with respect to the variable plate and the casing, where e signifies the eccentricity of the pump delivery set, preferably of the pump running set, and of the toothings between the variable plate and the casing.
  • variable internal gear pump arranged in the oil sump, for a four-cylinder passenger car engine.
  • This does not, however, mean that the invention is restricted to such an application. It could also, for example, be used in an automatic transmission as an oil pressure pump for switching and for supplying the transmission parts with oil.
  • the variable pump would then be positioned at the end of a continuous transmission input shaft, such that in this case, the chain wheel shown in the drawings is omitted, and instead the pump shaft is coupled, concentrically and rotationally fixed, to the transmission input shaft.
  • FIG. 1 an axial section in accordance with the gradient A-A in FIG. 2 ;
  • FIG. 2 a longitudinal section in accordance with the intersection line E-E in FIG. 1 ;
  • FIG. 3 a longitudinal section in accordance with the intersection line B-B in FIG. 1 ;
  • FIG. 4 a view of the variable plate, the variable spring and the pump running set in the pump casing, with the cover ( 30 ) removed, in the position in which the pump exhibits its maximum possible delivery amount;
  • FIG. 5 the same view as in FIG. 4 , but in the position in which the pump exhibits its minimum possible delivery amount;
  • FIG. 6 a longitudinal section through the pump along the intersection line D-D in FIG. 5 ;
  • FIGS. 7 and 8 an illustrative representation of the variable plate 13 together with its rolling off cylinder 25 .
  • the rotational direction of the running set shall be in the indicated direction of the arrow 32 , such that the respective suction and pressure side in accordance with the expanding and compressing delivery cells of the teeth is clearly provided.
  • the suction support 31 is arranged on the suction side of the running set, on which side the variable spring 28 can also be seen.
  • variable plate 13 4, 5 , 6 and 7 between the variable plate 13 and the casing 1 are under suction pressure, since the variable plate 13 is fitted in between the cavern base 33 of the casing and the casing-cover partition line, forming an axial seal but able to move.
  • the pressure space 35 which is hydraulically connected to the compressing delivery cells of the gear ring running set with the minimum possible choke (not shown in the drawings), is thus sufficiently sealed against excessively high volumetric losses with respect to the suction side.
  • the delivery cells of the gear ring running set are also sealed against each other by a minimum axial clearance between the variable plate 13 and the slaving disc 26 , such that here too, a clear hydraulic partition between the high pressure side and the suction side is provided.
  • FIG. 1 and 4 show the centre point of the internal rotor in a position in which the pump exhibits its largest possible delivery amount, since the eccentric axis E-E (in FIG. 1 ) of the running set toothing coincides with the axis of symmetry of the suction and pressure nodules in the casing and in the adjusting plate 13 .
  • This position is always needed at low pump speeds, if the oil viscosity is relatively low, i.e. when the motor is hot and in particular during heated idling, in order that the oil consumers of the motor are supplied with a sufficient amount of oil at a sufficient oil pressure.
  • the minimum pressure in the pressure chamber 35 should not drop substantially below 1 bar, even when bearing clearances of the motor parts have been enlarged by wear.
  • This maximum position is ensured by an exactly calculated bias on the variable spring which holds the adjusting plate 13 fixed on a stopper 36 .
  • the velocity pole for the rotational movement of the variable plate thus lies at Ml in FIG. 4 .
  • the system pressure in the pressure chamber 35 and in the compressing delivery cells of the gear ring running set increases.
  • a sum of adjusting moments arises around the velocity pole via the radial acting surfaces on the internal rotor 4 and on the adjusting plate 13 , such that the variable spring 28 is no longer capable of holding the adjusting plate 13 on the stopper 36 .
  • the variable system thus enters a poise which is determined by the moment equilibrium between the sum of the hydraulic adjusting moments and the moment of the variable spring 28 about the velocity pole Ml.
  • the adjusting plate 13 rotates clockwise in accordance with the representation in FIG.
  • the position P 2 i.e. a rotation by 90° of the centre point D I of the internal rotor 4 in accordance with FIG. 5 , is of course never assumed during normal motor operation, since as the speed of the system as a whole increases, the motor bearings always have a finite oil requirement which, however, does not remotely increase in proportion to the speed, as opposed to the delivery amount of a non-variable pump.
  • the oil requirement of the motor only increases roughly in proportion to the system pressure in the pressure chamber 35 , adapted to the flow resistance of all the oil consumers, the viscosity of the oil and the degree of wear of the shaft bearings of the motor.
  • the poise of the variable system of the adjusting pump in accordance with the invention is thus automatically set, such that the delivery amount of the pump exactly covers the oil requirement for the respective operational state of the system as a whole.
  • the designer then has the option of adapting the adjusting pump to the motor by varying the bias and the slope of the spring characteristic.
  • a new pump does not necessarily have to be designed for each engine size motor, as long as the range in size varies within certain limits.
  • the adjusting plate 13 not to roll off on the reference circles of the toothings between the adjusting plate 13 and the casing 1 but on two cylinder attachments, which roll off on each other, on the adjusting plate and the casing.
  • the embodiment of the cylinder attachment on the adjusting plate is shown somewhat more clearly in FIGS. 7 and 8 .
  • the cylinder attachment 24 can also be seen on the left of the image in FIG. 3 .

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Rotary Pumps (AREA)
  • Details And Applications Of Rotary Liquid Pumps (AREA)
US11/081,170 2004-03-17 2005-03-16 Displacement pump with variable volume flow Abandoned US20050214149A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE202004004231U DE202004004231U1 (de) 2004-03-17 2004-03-17 Volumenstromveränderbare Verdrängerpumpe
DE202004004231.2 2004-03-17

Publications (1)

Publication Number Publication Date
US20050214149A1 true US20050214149A1 (en) 2005-09-29

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ID=34813794

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Application Number Title Priority Date Filing Date
US11/081,170 Abandoned US20050214149A1 (en) 2004-03-17 2005-03-16 Displacement pump with variable volume flow

Country Status (6)

Country Link
US (1) US20050214149A1 (es)
EP (1) EP1735534A1 (es)
CA (1) CA2501103A1 (es)
DE (1) DE202004004231U1 (es)
MX (1) MXPA05007799A (es)
WO (1) WO2005093259A1 (es)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080019846A1 (en) * 2006-03-31 2008-01-24 White Stephen L Variable displacement gerotor pump
US20100290941A1 (en) * 2009-05-12 2010-11-18 Toyota Jidosha Kabushiki Kaisha Oil pump for a vehicle
CN102563325A (zh) * 2011-12-21 2012-07-11 浙江吉利汽车研究院有限公司 一种汽车机油泵
CN103452837A (zh) * 2012-06-01 2013-12-18 株式会社山田制作所 油泵的转子

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102019002949B4 (de) * 2019-04-24 2021-02-25 Bastian Voigt Innenzahnradpumpe
CN114198277B (zh) * 2021-12-14 2023-03-31 浙江工业大学 齿轮传动往复式活塞泵

Citations (10)

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Publication number Priority date Publication date Assignee Title
US3443378A (en) * 1967-04-04 1969-05-13 Trw Inc Hydrostatic single unit steering system
US3547565A (en) * 1967-07-21 1970-12-15 Reliance Electric Co Rotary device
US4658583A (en) * 1984-06-11 1987-04-21 Trw Inc. Double staged, internal rotary pump with flow control
US5702319A (en) * 1995-10-13 1997-12-30 Dana Corporation Hydromechanical system for limiting differential speed between differentially rotating members
US6126420A (en) * 1996-12-04 2000-10-03 Eisenmann; Siegfried Infinitely variable ring gear pump
US6152717A (en) * 1998-06-11 2000-11-28 Unisia Jecs Corporation Internal gear pumps
US6195990B1 (en) * 1999-01-13 2001-03-06 Valeo Electrical Systems, Inc. Hydraulic machine comprising dual gerotors
US6244839B1 (en) * 1997-11-14 2001-06-12 University Of Arkansas Pressure compensated variable displacement internal gear pumps
US20030026722A1 (en) * 2000-03-27 2003-02-06 Denso Corporation Trochoid gear type fuel pump
US6568929B2 (en) * 2001-03-05 2003-05-27 Denso Corporation Trochoid gear pump having means for canceling imbalance load

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1486836A (en) * 1923-04-28 1924-03-11 Hill Compressor & Pump Company Rotary-pump pressure control
US2969021A (en) * 1958-04-16 1961-01-24 Acc Emanuel Di G E R Emanuel & Automatic device for adjusting the output of rotary hydraulic machines
ES2192242T3 (es) * 1996-12-04 2003-10-01 Siegfried A Dipl-Ing Eisenmann Bomba anular de engranajes continuamente variable.
DE10338212A1 (de) * 2003-08-20 2005-03-10 Zahnradfabrik Friedrichshafen Volumenstromvariable Rotorpumpe

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3443378A (en) * 1967-04-04 1969-05-13 Trw Inc Hydrostatic single unit steering system
US3547565A (en) * 1967-07-21 1970-12-15 Reliance Electric Co Rotary device
US4658583A (en) * 1984-06-11 1987-04-21 Trw Inc. Double staged, internal rotary pump with flow control
US5702319A (en) * 1995-10-13 1997-12-30 Dana Corporation Hydromechanical system for limiting differential speed between differentially rotating members
US6126420A (en) * 1996-12-04 2000-10-03 Eisenmann; Siegfried Infinitely variable ring gear pump
US6244839B1 (en) * 1997-11-14 2001-06-12 University Of Arkansas Pressure compensated variable displacement internal gear pumps
US6152717A (en) * 1998-06-11 2000-11-28 Unisia Jecs Corporation Internal gear pumps
US6195990B1 (en) * 1999-01-13 2001-03-06 Valeo Electrical Systems, Inc. Hydraulic machine comprising dual gerotors
US20030026722A1 (en) * 2000-03-27 2003-02-06 Denso Corporation Trochoid gear type fuel pump
US6568929B2 (en) * 2001-03-05 2003-05-27 Denso Corporation Trochoid gear pump having means for canceling imbalance load

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080019846A1 (en) * 2006-03-31 2008-01-24 White Stephen L Variable displacement gerotor pump
US20100290941A1 (en) * 2009-05-12 2010-11-18 Toyota Jidosha Kabushiki Kaisha Oil pump for a vehicle
US8684712B2 (en) * 2009-05-12 2014-04-01 Toyota Jidosha Kabushiki Kaisha Oil pump for a vehicle
CN102563325A (zh) * 2011-12-21 2012-07-11 浙江吉利汽车研究院有限公司 一种汽车机油泵
CN103452837A (zh) * 2012-06-01 2013-12-18 株式会社山田制作所 油泵的转子

Also Published As

Publication number Publication date
MXPA05007799A (es) 2006-01-18
CA2501103A1 (en) 2005-09-17
WO2005093259A1 (de) 2005-10-06
DE202004004231U1 (de) 2005-07-28
EP1735534A1 (de) 2006-12-27

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