GB2498156A - Hydraulic machine with electronically controlled valves - Google Patents

Hydraulic machine with electronically controlled valves Download PDF

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Publication number
GB2498156A
GB2498156A GB1307205.3A GB201307205A GB2498156A GB 2498156 A GB2498156 A GB 2498156A GB 201307205 A GB201307205 A GB 201307205A GB 2498156 A GB2498156 A GB 2498156A
Authority
GB
United Kingdom
Prior art keywords
hydraulic machine
piston
operating mode
regulator
cylinder units
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.)
Withdrawn
Application number
GB1307205.3A
Other versions
GB201307205D0 (en
Inventor
Bja Rn Beuter
Alejandro Lopez-Pamplona
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 GB201307205D0 publication Critical patent/GB201307205D0/en
Publication of GB2498156A publication Critical patent/GB2498156A/en
Withdrawn legal-status Critical Current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
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B7/00—Piston machines or pumps characterised by having positively-driven valving
    • F04B7/0076—Piston machines or pumps characterised by having positively-driven valving the members being actuated by electro-magnetic means
    • 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
    • F04B7/00—Piston machines or pumps characterised by having positively-driven valving
    • 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
    • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/06—Control using electricity
    • 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
    • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/06—Control using electricity
    • F04B49/065—Control using electricity and making use of computers
    • 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
    • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/22—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00 by means of valves
    • 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
    • F04B2201/00—Pump parameters
    • F04B2201/12—Parameters of driving or driven means
    • F04B2201/1202—Torque on the axis
    • 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
    • F04B2205/00—Fluid parameters
    • F04B2205/06—Pressure in a (hydraulic) circuit

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Computer Hardware Design (AREA)
  • Fluid-Pressure Circuits (AREA)

Abstract

A hydraulic machine (DDU unit) having a number of piston/cylinder units (10) which can be controlled in each case by means of valves (14, 16) positioned upstream and downstream, which valves can in turn be activated by means of an electronic regulator (2) so as to switch the hydraulic machine selectively into a pump operating mode and/or a motor operating mode. The regulator selectively switches the individual piston/cylinder units or unit groups separately from one another into individually selectable operating modes as a function of certain regulating variables.

Description

Description
HYDRAULIC MACHINE WITH ELECTRONICALLY CONTROLLED VALVES
The inventibn relates generally to a valve-controlled hydraulic machine according to the preamble of Claim 1 and to a regulating method for such a hydraulic machine.
Such valve-controlled hydraulic machines are. knovn, for example, from EP 1 537 333 B1. This document shows a hydraulic machine of akial or radial piston design, which can be operated as a motor or as a pump, the delivery volume or absorption volume being almost infinitely variably adjustable via the valve control, with a stepped adjustment also being known in the prior art. In an exemplary embodiment according to this prior art, the hydraulic machine is èmbbdied as an axial pThton machine, in which a multiplicity of pistons arranged in a cylinder are supported on a rotatably mounted swash plate. Each of these Pistons, with the associated cylinder space, defines a working space, which via a low-pressure-side valve and a * . . high-pressure-side valve is connectable to a pressure-.
mediUm inlet or a prèssu±t-medium oUtlet. In the known * . solution,. the two valves are embodied as electrically deblockabj.e or blockable non-return valves which areS drivable via the electric pump-motor control and are to be operated in the respective working space in the so-called "full mode", in the "partial mode" or in the"idel mode".
As a result, the delivery volume or absorption volume can in this particular case be adjusted infinitely variably ____ from a maximum value to zero.
The hydraulic machine is operated, via a control unit of the.pump-moto± control, according to a regulating algorithm, in order to achieve an overall delivery vblume flow (pump) or overall absorption volumef1ow (motor) with the lowest pulsation possible. The volume flow adjustment bften takes place here according to a-forward phase control, but it may also be catried out according to a reverse phase control or a phase cutout control.
Hydraulió machines with absorption/delivery volume variable via the valve control are also called Digital Displacement Units (DDU) . In such hydraulic machines, all displacement principles are fundamentally conceivable. However, piston machines, in partioular of radial pistOn design, are advantageous, since they enable. the input and output for each displacer to be separately designed and thus actively controlled. In this case, it may well be expedient to distinguish between pumii operation and motOr operation, so that the control element for the low-pressure connection 2D and the high-pressure connection may then differ in appearance. . In order to increase, for example, the prevailing hydraulic pressure in a hydraulic system, such as that illustrated inter alia in Fig. 2, the hydraulic machine of the type described above is switched to the pump mode, with the result that pressure medium is fed into the system.
Superfluous amounts of pressure medium in this mode cannot, however, be remOved from the system by the hydraulic machine operating as a pump. Thatis to.say, any excess pressure medium can then be removed froi the system only by the consumer, by leakage, additional pressure accumulators, etc. .. . . . . If a very rapid pressure build-up is required in the system, accordingly the maximum amount of pressure medium * deliverable by the hydraulic machine (in the "full mode") has to be delivered as quickly as possible. However, this may result in overshoots inthe pressure profile owing to a pressure medium excess dependent *on the regulation sluggishness. The pressure medium can, however, be-removed fran the system only via the above-mentioned leakage or via the various consumers, which ultimately results in a slow decrease of the system pressure tothe desired value. To put it another way, when the regulation requires-a setting value below zero (which may be the case when the pressure in the system reaches a very high value), then the bDU unit turns off the volume flow (all piston-cylinder, units are switched to-idle running), since in the pump bperaticn a negative delivery is not possible. If therefore the excess pressure in the system is too high, presspre' is reduced only via the components in the system: The internal dynamics of this pressure reduction are, however, dependent on the system and its operating point-and are therefore difficult to regulate. . In view of this current situation, it is an object of the present invention to provide a hydraulic machine of the above-mentioned geheric type and a regulating method for this hydraulic machine, in order to be able-to set a desired pressure more accurately. . * 30 This object is achieved by a hydraulic machine having the * features of Claim 1 and by a method having the method steps according to Claim 7. Advantageous configurations of the -* invention are provided in the subclaimâ., -The basic idea of the invention consists in changing the current operating mode of a hydraulic machine (preferably DDU) not as a jhole, but partially, i.e. for at least one * 5 selected piston/cylinder unit; as a function of a deviation, from a detected actual value to a desired.value and thus in simultaneously operating the hydraulic machine partially in a pump operating mode and partially in a motor operatin mode. Within the operating modes, regulation to full-load, partial-load or idle operationLis then also optionally possible, individually or associated with the operting mode.
According to the invention, accordingly a hydau1ic machine has a number of piston/cylinder units which can be dontrolled in each case by means of valves positioned upstream and downstream, which valves can in turn be activated by means of an electronic regulätorso as to * switch the hydraulic machine selectively into a pump operating mode and/or a motor operating mode. In this case, it is provided that the regulator selectively switches the individual piston/cylinder units or unit groups separately from one another into individually selectable or selected operatingmodes.
The switching of the working node of specifically selected piston/cylinder units (pump to motor or motor to pump), in order to be able to switch from a positive pressure-medium delivery (pump operation) ihto a negative pressure-medium delivery (motor operation) (depending on the requirement/presetting of a preferably digital pressure regulator) has the advantage of a markedly improved controllability of the hydraulic machine. Since the actuators (pump/motor) can work in the positive and (simultaneously partially) negative range, quicker regulators can be designed which deliver pressure medium as quickly as possible. If an excessive pressure thereby arises in the system (overshooting), this can be actively reduced by the regulating actuatpr (quick reduction) instead of having to wait until the system has used up the superfluous amount of pressure medium.
According to one aspect of the invention? it is povided that the regulator selectively switches, within the operating iftode. individually selected for selected pistcn/cylinder units or unit groups, into full-load or partial-load operation. To put it another way, the absorption volume and/or delivery volume of the piston/c'linder units is set individually or in groups solely for the selected and/or the non-selected units. In this way, a pressure reduction can take place in the event of an overshoOting, or a pressure build-up in the event of 20. an undershobting, in a finely regulated manner.
The regulation of the hydraulic machine can furthermore preferably be adjusted to the regulation of the consumers of the system (delivery tate of the pump and absorption volume of the mbtor can be matched to one another) , with the result that the regulation as a whole is improved.
Moreover, a hydraulic system having a plurality of volume flow sources (pumps) each of different size is conceivable.
A higher-level regulation/monitoring could detect possible pressure overshoots in the system and decide from which DDU 4jhich piston-cylinder unit is to be switched ibto the niotor operation -with the aim of keping the pulsation in the system as low aspbssible. Here, it should be pointed out that wheh piston-cylinder units of different nominal sie are available, this makes it possible to calculate which of these piston-cylit-ider units is/are needed to remov.a S particular amount of pressure medium (e.g. hydraulic oil, coolant, etc.) from the system.
The regulating method according to Claim 7. sees the following fundamental -detecting an actual pressure value in a hydraulic system connected to the hydraulic machine, or a torque value, -comparing the actual pressure value or actual torque value (at a drive shaft for the piston-cylinder units) with a desired value and determining a deviation, and -switching the current operating mode individually for selected or selectable piston-cylindet units or unit.groüps of the hydraulic machine ath a function of the deviation.
This method is applicable in particular in a hydraulic machire 0DU having the features of the preamble of Claim 1.
The invention will be explained in more detail below with the aid of a preferred exemplary embodiment with reference to the accompanying figure.
Fig. 1 shows a preferred exemplary embodiment of a pressure regulation having a DDU/DVR unit, in which the individual cylinders are freely switchable between pump and/or motor operation. . Fig. 2 shows the exemplary structure of a hydraulic machine of radial piston design in the present case and. 7.
Fig. 3 shows a pressure regulation having a DDO/DVR unit
according to the prior art for comparison.
5. Illustrated in Fig. I is a pressure regulation according to the invention having.a hydraulic machine, preferably a DDtJ/DVR unit 1, essentially consisting of an electrical/electronic machine regulator 2 having an input interface 4 for inputting a desired pressute value for a hydraulic system 6 (for example a construction machine) and an output interface 8, to which the DDrJ-DVR unit 1 (hydraulic machine) is connected.
The hydraulic machthe. 1 may, for example, be a valve-controlled piston machine (axial or radial pislon machine), which can be operated in pump and/or motor mode with a variable delivery vblume and/or absorption volume. Such a piston machine, as is illustrated by way of examle in Fig. 2, has, according to the description regarding the prior art already given at the outset, a plurality of pistons 10, which are slidingly guided in separate cylinder pressure spaces 12 and which are controlled via individually associated low-pressure valves 14 and high-pressure valves 16. The low-pressur valved 14 connect the pressure spaces 12, which are in each case variable in volume, by the pistons 10, to a pressure-medium tank 18, whereas the high-pressure valves 16 connect the respective pressure spaces 12, for example, to a consumer or consumers of the hydraulic system 6, it being possiblefor further :, 30 hydraulic regulating elements (not'showi). tobe interposed between the consumers and the hydraulic thachine 1.
* In principle, DDU units allow a quick switching of the ope±-ating mode of the hydraulic machine from the pump operation into the motor operation and vice versa MOreover, it is possible, as has already been stated above, --S to svlitch the hydraulic machine within the selected operating ruode into a full-load, any desired partial-load o an idle operation.
According to the invention, provision i now made to switch the operating mode of individual piston/cylinder units 10 within the hydraulic machine 1 from the pump operation into the motor operation, or vice versa, as a function of the detected pressure conditions in the hydraulic system 6.
That is to say, if, in the case of a pump operation for increasing the prevailing pressure in the system 6 to a desired pressure, too much pressure medium is fed into the hydraulic system 6 (overshoot behaviour), according to the invention one or even more than one (selected) cylinder/piston units 10 of the (same) hydraulic machine 1 can be switched *into the motor operating mode with, optionally additionally, correspondingly selected full-load or partial-load operation. This/these piston/cylinder unit(s) 10 of the hydraulic machine 1can then remove the ekcess amount of pressure meditiin quickly and in a controlled wanner from the system 6 (preferably hydraulic system).
Since accordingly the actuators of the system (of the * * hydraulic machine) can operate individually both in the positive rarie (deliver pressure-medium) and in the negative range (consume/reduce pressure medium), it is * . possible to design the regulator 2 for the individual * * driving cf the individual piston/cylinder units 10 cr of selected unit pairs, in order to quickly attain the desired pressure value. . It should be pointed out here that the above regulator 2 for specific switching of individual cylinder/piston units lOin the pump operating mode of the hydraulic machine 1 front the pump oerat ion into the motor operation in principle also functions in the oppositedirection in the motor operating inodeof the hydraulic machine 1, nathely from the motor dperation into the pump operation. That is to say, if a system pressure is to be réducedto a particular pressure, the hydraulic machine 1 is switched into the rootbr operating mode. In the event of an undershcbting, caused by regulation, of the desired pressure, the regulator 2 according to the invention drives individual selected piston/cylinder units 10 or unit pairs, in order to switch these selected units 10 into the pump operating mode, optionally with further selectable full-load or partial-load operation, and thus increase the system pressure to the desired pressure (undershooting is.
avoided or quickly compensated) . This regulating process, namely the switchingfroni the motor operation into the pump operation as explained above, applies in particular to a torque regulation, according to which a hydraulic motor at first generates a torque on the shaft and then torque (components) are removed from the shaft by the switching into the pump operation. This results in improved regulating properties. . Consequently, what is disclosed is. a hydraulic machine (DDU unit) 1 having a number of piston/cylinder units 10 which can be controlled in each case by means of valves 14, 16 positionedupstreamand dowhstream, which valves can in 10.
turn be activated by means of an electronic regulator 2 so as to switch the hydraulicmachine 1 selecñively into a pump operatiri mode and/or a motor operating mode.
According to the invention, the regulator selectively switches the individual piston/cylinder units 10 or unit groups separately from one another into individually.
selectable operating modes as a fuhction of certain regulating variables. .. . . j1_.

Claims (1)

  1. <claim-text>Claims - 1. Hydraulic machine having a number of piston/cylinder units (10) which can be controlled in each case by means Of valves (14, 16) positioned upstream and downstream, which valves can in turn be activated by means of an electronic regulator (2) so as to switch the hydraulic machine (1), selectively into a UTh; operating mode and/or a motor operating mode, characterised in that the regulator (2) selectively switches the individual iston/cylinder units (10) or unit groups separately from one another into individually selectable operating modes.</claim-text> <claim-text>2. Hydraulic machine according to Claim 1, characterisedhy a desired pessure input device, by means of which a -desited pressure value can be preset in the regulator (2), according to which value the regulator (2) switches the hydraulic machine (1) as a whole into a pump or motor operating mode.</claim-text> <claim-text>3. Hydraulic machine according to Claim 2, characterised by a pressure sensor for deteting the actual pressure value and a comparator for determining a deviation between the detected actual pressure value and the preset desired pressure value, on the basis of which deviation tie regulator (2) selects piston/cylinder units (10) of the hydraulic machine (1) individually or in groups and switches them into another Selected operating mode, 4. Hydraulic machine according to one of the preceding claims, characterised in that the regulator (2) selectively -switches, within the operating mode individually selected for selected piston/dylinder units (10) or unit groups; into full-load or partial-load operation.5. Hydraulic machine according to one of the receding claims, oharacterised in that, in the case where the -hydraulic machine (1) is in the pump operating mode, the regulator (2) selectively switches selected piston-cylinder units (10) or unit groups into the thotor operating mode and leaves the remaining piston-cylinder units-(10) in the pump operating. thode.6. Hydraulic machine according to one of the preceding claims, characteri.sed in that, in the case where the hydraulic machine (1) is in the motor operating. mode, the regulator (2) selectively switches selected piston-cylinder units (10) or unit groups into the pump operating mode. and leaves the remaining piston-cylinder units (10) in the motor operating mode.7. Hydraulic machine according to one of the-preceding claims, characterised in that a. pressure, a torque or a volume flow is settable by the regulator (2) - 8. Regulating method for selectively operating a hydraulic machine (1) , havin a plurality of piston/cylinder units (10), in a pump or motor operating mode having the method steps: . . . detecting an actual pressure value in a hydraulic sj'stern (6) connected to the hydraulic machine (1), or an actual torque value, . . . . . -comparing the actual pressure value or actual torque a1ue with a desired value -and determining a deviation, and--C -- 13 -switching the current operating mode individually for selected or electab1e piston-cylinder units or unit groups of the hydraulic machine (1) as a function of the deviation. 5.9. Regulating method according to Claim 8, characterisedby the method step: . . . setting the absorption volume and/or delivery volume of the piston/cylinder units individually or in groups solely for the selected and/or the non-selected units.. . .</claim-text>
GB1307205.3A 2010-09-21 2011-09-16 Hydraulic machine with electronically controlled valves Withdrawn GB2498156A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102010046217A DE102010046217A1 (en) 2010-09-21 2010-09-21 Pressure control with DDU / DVR units using engine cycles
PCT/EP2011/004649 WO2012038050A1 (en) 2010-09-21 2011-09-16 Hydraulic machine with electronically controlled valves

Publications (2)

Publication Number Publication Date
GB201307205D0 GB201307205D0 (en) 2013-05-29
GB2498156A true GB2498156A (en) 2013-07-03

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Family Applications (1)

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GB1307205.3A Withdrawn GB2498156A (en) 2010-09-21 2011-09-16 Hydraulic machine with electronically controlled valves

Country Status (4)

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US (1) US20140147293A1 (en)
DE (1) DE102010046217A1 (en)
GB (1) GB2498156A (en)
WO (1) WO2012038050A1 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102018120001A1 (en) * 2018-08-16 2020-02-20 Moog Italiana S.R.L. Digital pump axis control system
JP2020197304A (en) * 2019-06-04 2020-12-10 アルテミス インテリジェント パワー リミティドＡｒｔｅｍｉｓ Ｉｎｔｅｌｌｉｇｅｎｔ Ｐｏｗｅｒ Ｌｉｍｉｔｅｄ Hydraulic machines and systems
WO2020264381A1 (en) * 2019-06-28 2020-12-30 Quidnet Energy Inc. Reversible reciprocating pump

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1537333B1 (en) * 2002-09-12 2006-06-14 Artemis Intelligent Power Ltd. Fluid-working machine and operating method
US20090210120A1 (en) * 2006-07-27 2009-08-20 Uwe Bernhard Pascal Stein Hydrostatic regenerative drive system
DE102008012538A1 (en) * 2008-03-04 2009-09-10 Robert Bosch Gmbh Hydraulic reciprocating engine for use as hydro pump or hydro motor, has multiple pistons and actuation pattern for actively operated valves are stored in electronic control device for different pump pressures and different flow rates

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB0407297D0 (en) * 2004-03-31 2004-05-05 Caldwell N J Fluid working machine with displacement control

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1537333B1 (en) * 2002-09-12 2006-06-14 Artemis Intelligent Power Ltd. Fluid-working machine and operating method
US20090210120A1 (en) * 2006-07-27 2009-08-20 Uwe Bernhard Pascal Stein Hydrostatic regenerative drive system
DE102008012538A1 (en) * 2008-03-04 2009-09-10 Robert Bosch Gmbh Hydraulic reciprocating engine for use as hydro pump or hydro motor, has multiple pistons and actuation pattern for actively operated valves are stored in electronic control device for different pump pressures and different flow rates

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Publication number Publication date
WO2012038050A1 (en) 2012-03-29
DE102010046217A1 (en) 2012-03-22
US20140147293A1 (en) 2014-05-29
GB201307205D0 (en) 2013-05-29

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