US20080145251A1 - High pressure pumping apparatus with coupled volumes in a pump working chamber - Google Patents

High pressure pumping apparatus with coupled volumes in a pump working chamber Download PDF

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Publication number
US20080145251A1
US20080145251A1 US11/999,765 US99976507A US2008145251A1 US 20080145251 A1 US20080145251 A1 US 20080145251A1 US 99976507 A US99976507 A US 99976507A US 2008145251 A1 US2008145251 A1 US 2008145251A1
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United States
Prior art keywords
volume
pressure
piston
pumping apparatus
outlet
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
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US11/999,765
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English (en)
Inventor
Hans-Georg Haertl
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.)
Agilent Technologies Inc
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Agilent Technologies Inc
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Filing date
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Assigned to AGILENT TECHNOLOGIES, INC. reassignment AGILENT TECHNOLOGIES, INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: HAERTL, HANS-GEORG
Publication of US20080145251A1 publication Critical patent/US20080145251A1/en
Abandoned legal-status Critical Current

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
    • G01N30/02—Column chromatography
    • G01N30/26—Conditioning of the fluid carrier; Flow patterns
    • G01N30/28—Control of physical parameters of the fluid carrier
    • G01N30/32—Control of physical parameters of the fluid carrier of pressure or speed
    • 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
    • F04B11/00—Equalisation of pulses, e.g. by use of air vessels; Counteracting cavitation
    • F04B11/005—Equalisation of pulses, e.g. by use of air vessels; Counteracting cavitation using two or more pumping pistons
    • F04B11/0075—Equalisation of pulses, e.g. by use of air vessels; Counteracting cavitation using two or more pumping pistons connected in series
    • F04B11/0083—Equalisation of pulses, e.g. by use of air vessels; Counteracting cavitation using two or more pumping pistons connected in series the pistons having different cross-sections
    • 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
    • F04B37/12—Pumps having pertinent characteristics not provided for in, or of interest apart from, groups F04B25/00 - F04B35/00 for special use to obtain high pressure
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
    • G01N30/02—Column chromatography
    • G01N30/26—Conditioning of the fluid carrier; Flow patterns
    • G01N30/28—Control of physical parameters of the fluid carrier
    • G01N30/36—Control of physical parameters of the fluid carrier in high pressure liquid systems
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
    • G01N30/02—Column chromatography
    • G01N30/26—Conditioning of the fluid carrier; Flow patterns
    • G01N30/28—Control of physical parameters of the fluid carrier
    • G01N30/32—Control of physical parameters of the fluid carrier of pressure or speed
    • G01N2030/326—Control of physical parameters of the fluid carrier of pressure or speed pumps

Definitions

  • the present invention relates to a pumping apparatus for delivering liquid at a high pressure at which compressibility of the liquid becomes noticeable.
  • HPLC high performance liquid chromatography
  • a liquid has to be provided usually at very controlled flow rates (e.g. in the range of microliters to milliliters per minute) and at high pressure (typically 200-1000 bar and beyond up to even 2000 bar) at which compressibility of the liquid becomes noticeable.
  • flow rates e.g. in the range of microliters to milliliters per minute
  • high pressure typically 200-1000 bar and beyond up to even 2000 bar
  • HPLC high performance liquid chromatography
  • GB 1522552 discloses a pumping system for HPLC having a flow inducer to provide a high pressure metering are liquid.
  • EP 0309596 A1 discloses an HPLC pump system providing stroke volume variation in order to reduce pulsations.
  • U.S. Pat. No. 6,712,587 B2 discloses a hydraulic amplifier pump for use in HPLC.
  • the object is solved by the independent claim(s). Further embodiments are shown by the dependent claim(s).
  • Embodiments according to the present invention provide a pumping apparatus for delivering liquid at a high pressure at which compressibility of the liquid becomes noticeable.
  • the pumping apparatus has a piston reciprocating in a pump working chamber having a first and a second volume. A movement of the piston into a first direction decreases the first volume and increases the second volume. Accordingly, a movement of the piston into a second direction opposite to the first direction increases the first volume and decreases the second volume.
  • the first and second volumes are coupled to each other as long as a pressure in the first volume exceeds a pressure in the second volume.
  • An outlet valve is provided for coupling the second volume with an outlet of the pumping apparatus as long as a pressure in the second volume exceeds a pressure at the outlet.
  • the coupling of the first and second volumes of the pump working chamber allows balancing forces onto the piston, so that a drive coupled to the piston for reciprocating the piston is exposed to lesser force requirements. This may allow using smaller drives which in turn may even provide an improved dynamic behavior and in general are usually less costly.
  • the pumping apparatus has a given area proportion A between a first effective area of the piston facing the first volume and a second effective area of the piston facing the second volume.
  • the first and second effective areas are opposing each other.
  • first effective area being greater than the second
  • the force compensation becomes increased with the area proportion A getting closer to one, while greater area proportions A lead to less compensation and thus greater force requirements onto the drive of the piston.
  • greater values of the area proportion A can lead to higher achievable pressure at the outlet of the pumping apparatus. Criteria for selecting the area proportion might be force requirements, dynamic, size, etc. of the piston drive.
  • area proportions (first effective area/second effective area) A of 2:1, 3:2, 4:3, etc. have been found useful for certain applications and balancing the contravening requirements of achievable outlet pressure and force requirements of the piston drive in certain applications.
  • the first volume of the pump working chamber receives liquid at an inlet pressure, which can be ambient pressure or provided by an inlet pump.
  • a control unit might be provided for controlling such inlet pressure to be in a given pressure proportion P to the pressure at the outlet of the pumping apparatus.
  • the pressure proportion P (outlet pressure/inlet pressure) is preferably selected essentially in accordance with the area proportion A, to be A ⁇ P.
  • the pressure proportion is selected to be 2:1 (i.e. the first effective area is twice as large as the second effective area) the pumping apparatus can provide an outlet pressure of up to twice the inlet pressure.
  • the control unit might control the inlet pressure, whereas the outlet pressure then follows based on the given pressure proportion.
  • One or more pressure sensors for sensing values indicative of pressure might be provided at the inlet and/or outlet of the pumping apparatus, thus allowing to sense and control the pressures and/or the pressure proportion P.
  • the inlet pressure is preferably provided by an inlet pump coupled to at least one of the first and second volumes to provide liquid thereto at the inlet pressure.
  • the inlet pump might be any kind of pump allowing to provide the liquid at the inlet pressure and might be embodied as a piston pump or a gear pump.
  • the inlet pump is adapted to provide the liquid at 1/P (half in this example) of a required outlet pressure of the pumping apparatus, with the pumping apparatus providing a value of the area proportion A (2:1 in this example).
  • the inlet pump might be embodied mainly to provide the inlet pressure but with lesser accuracy requirements regarding liquid flow rate.
  • the pumping apparatus in this embodiment might be designed to provide flow rates at higher accuracy, so that in total a pump results allowing driving liquids with high flow rate accuracy and at high pressure.
  • the piston is provided to have on one side the first effective area facing the first volume and on an opposing side the second effective area facing the second volume.
  • the side of the piston facing the second volume is preferably coupled via a piston rod to a drive.
  • a return mechanism coupled to the piston and being adapted for counteracting against the movement of the piston might be provided to apply a force onto the piston in opposite direction as the drive, as well known in the art and disclosed e.g. in the aforementioned EP 0309596 A1, the teaching thereof shall be incorporated herein by reference.
  • Sealing might be provided for sealing the pump working chamber against the drive and/or to seal the first and second volumes against each other.
  • the drive might comprise at least one of a spindle drive mechanism, a linear motor, a stepper motor, a DC-Motor, a VR-Motor; a driving rod coupled to the piston.
  • the return mechanism might comprise at least one of a spring, a hydraulic cylinder, a drive mechanism, a deflection mechanism, a return rod coupled to the piston.
  • Valves applied might be one or more of a check valve, an active valve, a solenoid valve.
  • the inlet pressure might be in the range of 100 to 1000 bar, preferably between 300 and 700 bar, and more preferably about 600 bar.
  • the achievable outlet pressure might be in the range of 500 to 2000 bar, preferably between 800 and 1500 bar, and more preferably about 1200 bar.
  • a flow rate of the liquid at the outlet might be in the range of nanoliter per minute to milliliter per minute, and more preferably in the range of microliter per minute to milliliter per minute.
  • the coupling between the first and the second volumes can be provided by a conduit and preferably further comprises a coupling valve.
  • the first and second volumes are both coupled to the inlet pump, so that the coupling might also comprise the inlet pump.
  • Embodiments of the invention can be partly or entirely supported by one or more suitable software programs, which can be stored on or otherwise provided by any kind of data carrier, and which might be executed in or by any suitable data processing unit.
  • Software programs or routines can be preferably applied to control the piston movement e.g. to minimize pump ripple and/or compensate physical effects influencing precision and accuracy.
  • FIG. 1 shows an exemplary embodiment of a pumping apparatus 10 for delivering liquid at a high pressure at which compressibility of the liquid becomes noticeable.
  • FIG. 2 shows a more detailed embodiment of the pumping apparatus 10 .
  • FIG. 3 shows an embodiment of a dual parallel pump 300 comprising to pumping apparatuses 10 A and 10 B, which can be embodied as shown in the FIGS. 1 and 2 .
  • FIG. 4 shows another embodiment of a dual parallel pump in a principle drawing.
  • FIG. 5 shows a liquid separation system 500 .
  • a piston 20 is reciprocating in a pump working chamber 30 having a first volume V 1 and a second volume V 2 .
  • a movement of the piston 20 into a first direction 40 decreases the first volume V 1 and accordingly increases the second volume V 2 .
  • a movement of the piston 20 in a second direction 50 increases the first volume V 1 and decreases the second volume V 2 .
  • the first and second volumes V 1 and V 2 are separated from each other in the pump working chamber 30 , in the embodiment of FIG. 1 by a seal 60 , which can be e.g. a polymeric piston seal as known in the art.
  • the first and the second volumes V 1 and V 2 are coupled to each other via a first conduit 70 , a pressure supply 80 , a second conduit 90 , and a coupling valve 100 .
  • the pressure supply 80 is providing liquid at a pressure Psup. Due to the coupling of the first volume V 1 and the pressure supply 80 via the first conduit 70 , the volume V 1 will also be under pressure Psup. Accordingly, due to the coupling of the second volume V 2 with the pressure supply 80 via the second conduit 90 and the coupling valve 100 , the second volume V 2 will also be under pressure Psup. However, due to the unidirectional flow characteristics of the coupling valve 100 , the second volume V 2 will only be at pressure Psup as long as the pressure in the volume V 2 does not exceed Psup.
  • an outlet 110 is coupled to a system at a pressure Psys.
  • an outlet valve 120 is provided at the outlet 110 , which also provides a unidirectional flow control, so that the outlet valve 120 is coupling the second volume V 2 to the system Psys as long as the pressure in the second volume V 2 exceeds the system pressure Psys.
  • a piston rod 130 is coupled to the piston 20 in order to move the piston 20 .
  • a drive 140 is coupling to the piston rod 130 in order to drive the piston 20 .
  • the drive 140 might comprise a return mechanism (not shown in FIG. 1 ) as known in the art.
  • a drive seal 150 is provided for sealing the second volume V 2 against the piston rod 130 and the drive 140 . Details about the drive 140 , the return mechanism, the rod 130 are disclosed e.g. in the aforementioned EP 0309596 A1 and shall be incorporated herein by reference.
  • the piston 20 has a first effective area A 1 facing the first volume V 1 and a second effective area A 2 facing the second volume V 2 .
  • the first effective area A 1 is larger than the second effective area A 2 , and both effective areas A 1 and A 2 are at opposing sides of the piston 20 .
  • the ratio of the second effective area A 1 to the first effective area A 2 shall be denoted as A. In the example of FIG. 1 , the ratio A is about 3:2.
  • FIG. 2 substantially corresponds to the principle drawing of FIG. 1 .
  • the first volume V 1 is directly coupled to the second volume V 2 via the second conduit 90 .
  • the coupling valve 100 is now located coupled directly to the outlet of the first volume V 1 .
  • the second conduit 90 which might be embodied as a capillary, is coupled via a fitting 210 to the coupling valve 100 and via another fitting 220 to the second volume V 2 .
  • Another fitting 230 is shown in FIG. 2 to couple another conduit 240 , which might also be a capillary, to the outlet valve 120 .
  • the first volume V 1 receives the liquid via the first conduit 70 at the pressure Psup, and the second volume V 2 outputs liquid at the outlet 110 at the pressure Psys.
  • Pressure sensors might be coupled to the inlet and/or the outlet of the pumping apparatus 10 in order to measure one or both of the pressures Psup and Psys, as shown e.g. in FIG. 3 below.
  • the piston 20 shall be at its left dead center, so that the first volume V 1 being maximal and the second volume V 2 being minimal.
  • the first volume V 1 is at the pressure Psup as provided from the pressure supply 80 .
  • the coupling valve 100 opens and supplies liquid into the second volume V 2 . Any liquid volume which cannot be filled into the second volume V 2 (in case V 2 is smaller than V 1 ) will be provided (back) to the pressure supply 80 .
  • a second pumping apparatus is used e.g. in parallel (see below)
  • liquid which cannot be filled into the second volume V 2 can be provided to a first volume V 1 ′ of such second pumping apparatus.
  • the ratio of the first effective area A 1 to the second effective area A 2 shall be A, and the input pressure Psup shall be selected (or is preferably controlled) to be the output pressure Psys divided by A.
  • the movement of the piston into direction 40 will supply liquid from the first volume into the second volume. Due to the unidirectional valve 120 and as Psys should be larger than the pressure resulting in the second volume V 2 , there will be no supply of liquid into the system during the first cycle.
  • the outlet valve 120 opens and the pumping apparatus 10 delivers liquid into the system during a third phase.
  • the liquid flow rate into the system is mainly determined by the second effective area V 2 and the velocity of the movement of this piston 20 .
  • pulsation effects i.e. pressure drops and over shooting
  • adequate counter measures as known in the art can be provided.
  • One way to encounter pulsation can be to expedite the second phase, i.e. to control the piston 20 to move faster during the beginning of the second phase.
  • a first force F 1 is proportional to the product of the pressure in the first volume V 1 and the first effective area A 1 .
  • a second force F 2 is proportional to the pressure in the second volume V 2 and the second effective area A 2 .
  • two pumps are provided either in serial or parallel manner, as known in the art.
  • the operation of both pumps is typically shifted by about 180 degrees, so that one pump is supplying into the system while the other is sucking liquid, and vice versa.
  • first conduits 70 A and 70 B are coupled to the pressure supply 80 , which might be a supply pump 310 and might have an outlet valve 320 .
  • An inlet pressure sensor 330 might be coupled to the common inlet of the pumping apparatuses 10 A and 10 B.
  • the outlet 110 A of the first pumping apparatus 10 A and the outlet 110 B of the second pumping apparatus 10 B are coupled together to supply the system.
  • a pressure sensor 340 might be coupled to the common outlets 110 A and 110 B.
  • liquid from the first volume V 1 of the first pumping apparatus 10 A which cannot be filled into the second volume V 2 thereof can—in the embodiment of FIG. 3 —be provided to a first volume V 1 ′ of the second pumping apparatus 10 B, and vice versa.
  • the two pumping apparatuses 10 A and 10 B can also be coupled in a serial manner (not shown in the figures), with the outlet 110 A of the first pumping apparatus 10 A being coupled to the inlet 70 B of the second pumping apparatus 10 B, and the outlet 110 B of the second pumping apparatus 10 B providing the outlet of the pump.
  • the two pumping apparatuses 10 A and 10 B share a common first volume V 1 .
  • Both pistons 20 A and 20 B are moved either into direction 40 or the opposite direction 50 .
  • the volume V 1 remains substantially the same, and a compensation between both pumping apparatuses 10 A and 10 B is achieved.
  • the supplying pump supplies virtually “through” V 1 and the valve into V 2 of the other pump, which at that phase is sucking liquid.
  • FIG. 5 shows a liquid separation system 500 .
  • a pump 400 which might be embodied as illustrated in FIG. 3 or 4 , drives a mobile phase through a separating device 510 comprising a stationary phase.
  • a sampling unit 520 is provided between the pump 400 and the separating device 510 in order to introduce a sample fluid to the mobile phase.
  • the stationary phase of the separating device 510 is adapted for separating compounds of the sample liquid.
  • a detector 530 is provided for detecting separated compounds of the sample fluid.
  • a fractionating unit 540 can be provided for outputting separated compounds of sample fluid.
  • liquid separation system 500 Further details of such liquid separation system 500 are disclosed with respect to the Agilent 1200 Series Rapid Resolution LC system or the Agilent 1100 HPLC series, as both provided by the applicant Agilent Technologies, under www.agilent.com which shall be in cooperated herein by reference.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Reciprocating Pumps (AREA)
US11/999,765 2006-12-13 2007-12-07 High pressure pumping apparatus with coupled volumes in a pump working chamber Abandoned US20080145251A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP06126014A EP1795749B1 (de) 2006-12-13 2006-12-13 Hochdruckpumpe mit gekoppelten Kammern im Kompressionsraum
EP06126014.7 2006-12-13

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US20080145251A1 true US20080145251A1 (en) 2008-06-19

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EP (1) EP1795749B1 (de)
DE (1) DE602006005449D1 (de)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20120241467A1 (en) * 2011-03-23 2012-09-27 Kaltenbach & Voigt Gmbh Metering Device
US20140090728A1 (en) * 2011-02-11 2014-04-03 Thomas Kotsiopoulos System for supercritical fluid extraction
US11035350B2 (en) * 2008-08-07 2021-06-15 Agilent Technologies, Inc. Synchronization of supply flow paths

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030118459A1 (en) * 2001-12-21 2003-06-26 Gerhardt Geoff C. Hydraulic amplifier pump for use in ultrahigh pressure liquid chromatography
US20030183565A1 (en) * 2002-03-26 2003-10-02 Michel Jonathan D. Chromatography system for automatically separating different compounds in a sample

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2076904A (en) * 1980-05-16 1981-12-09 Harper Alan Roger Pump or metering device
GB8522466D0 (en) * 1985-09-11 1985-10-16 British Syphon Ind Plc Liquid dispence system
DE3785207T2 (de) * 1987-09-26 1993-07-15 Hewlett Packard Gmbh Pumpvorrichtung zur abgabe von fluessigkeit bei hohem druck.

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030118459A1 (en) * 2001-12-21 2003-06-26 Gerhardt Geoff C. Hydraulic amplifier pump for use in ultrahigh pressure liquid chromatography
US20030183565A1 (en) * 2002-03-26 2003-10-02 Michel Jonathan D. Chromatography system for automatically separating different compounds in a sample

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11035350B2 (en) * 2008-08-07 2021-06-15 Agilent Technologies, Inc. Synchronization of supply flow paths
US11635065B2 (en) 2008-08-07 2023-04-25 Agilent Technologies, Inc. Synchronization of supply flow paths
US20140090728A1 (en) * 2011-02-11 2014-04-03 Thomas Kotsiopoulos System for supercritical fluid extraction
US9528660B2 (en) * 2011-02-11 2016-12-27 Thomas Kotsiopoulos System for supercritical fluid extraction
US20120241467A1 (en) * 2011-03-23 2012-09-27 Kaltenbach & Voigt Gmbh Metering Device
US9352344B2 (en) * 2011-03-23 2016-05-31 Kaltenbach & Voigt Gmbh Metering device

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Publication number Publication date
EP1795749B1 (de) 2009-03-04
EP1795749A1 (de) 2007-06-13
DE602006005449D1 (de) 2009-04-16

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