EP2646686A1 - Pompe de chromatographie - Google Patents

Pompe de chromatographie

Info

Publication number
EP2646686A1
EP2646686A1 EP11790755.0A EP11790755A EP2646686A1 EP 2646686 A1 EP2646686 A1 EP 2646686A1 EP 11790755 A EP11790755 A EP 11790755A EP 2646686 A1 EP2646686 A1 EP 2646686A1
Authority
EP
European Patent Office
Prior art keywords
inlet
outlet
piston
pump according
pump
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Withdrawn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
EP11790755.0A
Other languages
German (de)
English (en)
Inventor
Owe Salven
Bjorn Olovsson
Mats Lundkvist
Jan Kranse
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.)
Cytiva Sweden AB
Original Assignee
GE Healthcare Bio Sciences AB
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 GE Healthcare Bio Sciences AB filed Critical GE Healthcare Bio Sciences AB
Publication of EP2646686A1 publication Critical patent/EP2646686A1/fr
Withdrawn legal-status Critical Current

Links

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
    • F04B53/00—Component parts, details or accessories not provided for in, or of interest apart from, groups F04B1/00 - F04B23/00 or F04B39/00 - F04B47/00
    • F04B53/16—Casings; Cylinders; Cylinder liners or heads; Fluid connections
    • 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
    • F04B11/0008—Equalisation of pulses, e.g. by use of air vessels; Counteracting cavitation using accumulators
    • F04B11/0033—Equalisation of pulses, e.g. by use of air vessels; Counteracting cavitation using accumulators with a mechanical spring
    • 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
    • F04B53/00—Component parts, details or accessories not provided for in, or of interest apart from, groups F04B1/00 - F04B23/00 or F04B39/00 - F04B47/00
    • F04B53/06—Venting

Definitions

  • the present invention relates to a chromatography pump according to the preamble of claim 1.
  • Chromatography is a chemical process for identifying and quantifying compositions held in a sample and also for purification and extraction of compositions.
  • compositions in a solution are separated from each other as the solution moves through a stationary material held in a column.
  • the solution is pumped under high pressure through the stationary material in the column by one or several chromatography pumps.
  • chromatography pump systems In the preparation for the chromatography process air held in the chromatography pump has to be removed. Also, air held in the sample has to be removed. Therefore, chromatography pump systems often are provided with a purging arrangement which removes the air held in the chromatography pump in the beginning of the process.
  • the purging arrangement generates a vacuum at the outlet valve of the pump, so that air held within the pump is sucked out from the pump and the solution or sample simultaneously is sucked into the pump.
  • air bubbles tend to be trapped within the chromatography pump cylinder even if the purging arrangement has removed the major volume of air held in the chromatography pump.
  • the air bubbles trapped within the chromatography pump reduces the performance of the chromatography pump, so that the pressure and flow of the solution will fluctuate. This will influence on the overall chromatography mixing process, so that less accurate results will be achieved.
  • air bubbles tend to be trapped in the inlet and outlet channels of the pump, and also in the cylinder.
  • the air bubbles are trapped at stagnant zones i.e. at edges and corners formed in the known pump.
  • the object of the invention is to achieve a chromatography pump with automatic purging, which eliminates manual means for the purging operation.
  • Another object of the invention is to achieve a chromatography pump which facilitates air bubbles to be transported through the pump.
  • a further object of the invention is to achieve a chromatography pump in which air bubbles are prevented to be trapped.
  • a further object of the invention is to achieve a minimum of fluctuation in flow output and pressure of a chromatography pump.
  • inlet channel and outlet channel extend in a substantially straight direction there are no edges and corners where air bubbles can be trapped within the channels. Instead the air bubbles will pass through the cannels without influencing the performance of the chromatog- raphy pump. Thus, a chromatography pump with high performance is achieved.
  • an outlet of the inlet channel arranged in the cylinder head area has a substantially elliptic configuration. This configuration facilitates air bubbles to be transported out of the inlet channel and further to the outlet channel.
  • a cavity is arranged in the cylinder head area and an inlet of the outlet channel is arranged in the cavity.
  • the cavity has a form substantially corresponding to an arch. This configuration facilitates the transport of air bubbles out to the outlet channel.
  • the front element is made of PEEK material, titanium or hastelloy. Thereby, a high strength of the front element is achieved. Also, the surface properties of these materials can be adapted to prevent air bubbles to be trapped and tied on the surfaces in the channels and in the cylinder.
  • the surface roughness (Ra) of the walls of the inlet and outlet channels and of the wall of the cylinder head area are between 0,2 - 2,0, preferably between 1 ,0 - 2,0. This will prevent air bubbles to be tied to the surface of the inlet and outlet channels and of the wall of the cylinder head area.
  • the inlet and outlet valves are check valves provided with seated balls in which a weight arranged on the ball urges the ball against the seat.
  • a weight arranged on the ball urges the ball against the seat.
  • the cylinder head area has a normal which substantially coincides with the axis of the piston.
  • a compact design of the cylinder space is achieved. Because the inlet and outlet channels are connected to the cylinder head area and that the normal of the cylinder head area substantially coincides with the axis of the piston air bubbles in the cylinder will easily be transported out to the outlet channel.
  • Fig. 1 shows a diagrammatic cross section view of a prior art chromatography pump
  • Fig. 2 shows a cross section view of a preferred embodiment of a chromatography pump according to the invention
  • Fig. 3 shows a front view of the preferred embodiment of the chromatography pump according to the invention
  • Fig. 4 shows a cross section view of a second embodiment of a chromatography pump according to the invention
  • Fig. 5 shows a cross section view of a third embodiment of a chromatography pump according to the invention.
  • Fig. 6 shows an enlarged cross section view of a forth embodiment of a piston for a chromatography pump according to the invention.
  • Fig. 1 shows a diagrammatic cross section view of a prior art chromatography pump 101 , which comprises a cylinder 102 in which a piston 104 is arranged for a reciprocating movement.
  • the reciprocating movement of the piston 104 is generated by a driving means 106, such as an electric motor.
  • a front element 108 is provided with a cylinder head area 110 which together with the cylinder 102 and the piston 104 defines a cylinder space 112.
  • An inlet valve 114 and an outlet valve 116 in form of check valves are arranged in the front element 108.
  • An inlet channel 118 is arranged in the front element 108 between the inlet valve 114 and the cylinder head area 110, and an outlet channel 120 is arranged in the front element 108 between the cylinder head area 110 and the outlet valve 116.
  • air bubbles 134 tend to be trapped within the known chromatography pump 101 dis- closed in fig. 1 , especially in the inlet and outlet channels 1 18, 120 of the pump 101 , and also in the cylinder space 112.
  • One reason why the air bubbles 134 are trapped in the inlet and outlet channels 118, 120 is that the channels1 18, 120 are provided with stagnant zones, such as edges and corners 136.
  • Another reason is that the surface roughness of the wall surface of the channels are too smooth, which facilitates air bubbles 134 to be tied to the surfaces. Similar drawbacks can be found in the cylinder space 112 at the cylinder head area 110. Air bubbles 134 can also be trapped between the ball 126 and the seat 128 in the inlet and outlet valves 1 14, 1 16.
  • FIG. 2 shows a cross section view of a preferred embodiment of a chromatography pump 201 according to the invention.
  • the chromatography pump 201 comprises a cylinder 202 in which a piston 204 is arranged for a reciprocating movement along an axis 248.
  • a seal means 205 is arranged on the piston 204, so that leakage between the piston 204 and the cylinder 202 is minimized.
  • the reciprocating movement of the piston 204 is generated by a driving means 206, such as an electric motor.
  • a front element 208 is provided with a cylinder head area 210 which together with the cylinder 202 and the piston 204 defines a cylinder space 212.
  • An inlet valve 214 and an outlet valve 216 in form of check valves are arranged in the front element 208.
  • An inlet channel 218 is arranged in the front element 208 between the inlet valve 214 and the cylinder head area 210, and an outlet channel 220 is arranged in the front element 208 between the cylinder head area 210 and the outlet valve 216.
  • a liquid 222 held in a schematically disclosed container 224 is sucked into the cylinder space 212 through the inlet valve 214 and the inlet channel 218 due to vacuum generated in the cylinder space 212 by the piston 204.
  • a ball 226 within the valve 214 lifts from a seat 228 by the flow of the liquid 222 and open a passage for the liquid 222 between the ball 226 and the seat 228.
  • liquid 222 is prevented from entering the outlet valve 216 because the ball 226 seals against the seat 228.
  • channels 218, 220 and valves 214, 216 are filled with air.
  • the chromatography pump 201 is self purging.
  • liquid 222 is prevented from escaping the inlet valve 214 because the ball 226 seals against the seat 228.
  • An example of pressure and piston displacement of the chromatography pump 201 according to the invention is 200 bar and 125 ⁇ .
  • the flow generated by the pump is in the range 0 - 60 ml/minute.
  • the inlet and outlet channels 218, 220 in fig. 2 extend in a substantially straight direction with- out or with as few sharp edges or corners as possible, so that air bubbles 234 are prevented from being trapped within the channels 218, 220.
  • the channels 218, 220 are not provided with stagnant zones, such as edges and corners, and therefore air bubbles 234 will not be trapped within the channels. Instead the air bubbles 234 will pass through the cannels 218, 220 without influencing the performance of the chromatography pump 201.
  • the outlet channels extend obliquely to axis 248, as can be seen in the Figures.
  • the outlet channels 218 and 220 provide a substantially straight line connection between the cylinder head area 210 and their respective valves 214 and 216, and the straight lines are slanted relative to the axis 248 of the piston 204, and have divergent paths.
  • the configuration of the channels 218 and 220 provides improved flow, and also facilitates the cleaning of the pump 201. This is especially important when different liquids are used in the pump 201.
  • air bubbles 234 are unlikely to be trapped and the pump 201 will be purged automatically.
  • the surface roughness (Ra) of the walls 236 of the inlet and outlet channels 218, 220 and of the wall 238 of the cylinder head area 210 are between 0,2 - 2,0, preferably between 1 ,0 - 2,0. This will prevent air bubbles 234 to be tied to the wall 236 of the inlet and outlet channels 218, 220 and of the wall 238 of the cylinder head area 210.
  • the surface roughness can be achieved by special machining techniques.
  • the front element 208 is preferably made of PEEK material, titanium or hastelloy. Other materials are also possible. PEEK and hastelloy are registered trademarks. Thereby, a high strength of the front element 208 is achieved.
  • the surface properties of these materials can be adapted to the above-mentioned surface roughness values.
  • the liquid 222 must be pumped under high pressure through the stationary material 232 in the column 230. Therefore, the materials used in the front element 208 must have high strength properties.
  • Fig. 3 shows a front view of the preferred embodiment of the chromatography pump 201 according to the invention.
  • a cavity 242 is arranged in the cylinder head area 210 and an outlet 240 of the inlet channel 218 is arranged in the bottom part of the cavity 242.
  • an inlet 244 of the outlet channel 220 is arranged in the cavity 242.
  • the cavity 242 has a form substantially corresponding to an arch and the inlet 244 of the outlet channel 220 has conical form. This configuration facilitates the transport of air bubbles 234 out to the outlet channel 220.
  • the cylinder head area 210 has a normal 246 which substantially coincides with the axis 248 of the piston 204.
  • a compact design of the cylinder space 212 is achieved. Since the inlet and outlet channels 218, 220 are connected to the cylinder head area 210 and that the normal 246 of the cylinder head area 210 substantially coincides with the axis 248 of the piston 204 air bubbles 234 in the cylinder 202 will easily be transported out to the outlet channel 220.
  • Fig. 4 shows a cross section view of a second embodiment of a chromatography pump 301 according to the invention. Similar components as disclosed in fig. 2 will have same reference numbers.
  • the inlet and outlet valves 214, 216 are provided with seated balls 226 in which weights 303 are arranged on the balls 226 that urges the balls 226 against the seat 228. Thereby, air bubbles 234 are prevented from being trapped between the ball 226 and the seat 228 due to the force from the ball 226 on the seat 228. Also, the ball 226 is prevented from being stuck to the inner wall of the valves 214, 216 due to capillary forces.
  • the weights 303 are influenced by gravity forces and therefore the pump 301 according to this second embodiment has to be mounted in such a direction that the weights 303 rests on the balls 226 in the valves 214, 216.
  • a spring (not disclosed) in the valves 214, 216, which urges the ball 226 against the seat 228.
  • Fig . 5 shows a cross section view of a third embodiment of a chromatography pump 301 according to the invention. Similar components as disclosed in fig. 3 will have same reference numbers.
  • outlet channel 220 and the inlet and outlet valves 214, 216 extend in a substantially coincident direction, so that the pump 301 may be mounted with outlet channel 220 in a substantially vertical direction in relation to a horizontal plane 308.
  • air bubbles 234 within the pump 301 will easy leave the outlet channel 220, because of the gravitation influencing on the air bubbles 234 in the liquid.
  • Fig. 6 shows an enlarged cross section view of a forth embodiment of a piston 404 for a chromatography pump 401 according to the invention.
  • the piston 404 is provided with a circumferential seal 405 which in a direction radial outwardly is spring loaded by a circumferential leaf spring 407, so that a tight seal between the cylinder 402 and the piston 404 is achieved.
  • a tap 409 preferably made of titanium is arranged on the end part 41 1 of the piston 402. The tap 409 is attached to the piston 404 and fixates the seal 405 on the end part 41 1 of the piston 404.
  • the chromatography pump 201 , 301 , 401 according to the present invention is primary designed for pumping liquid 222. However, other fluids may also be pumped by the chromatography pump 201 , 301 , 401 according to the invention.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Details Of Reciprocating Pumps (AREA)
  • Reciprocating Pumps (AREA)

Abstract

L'invention porte sur une pompe de chromatographie comprenant un cylindre (202, 402) dans lequel un piston (204, 404) est agencé pour décrire un mouvement alternatif ; un élément frontal (208) muni d'une zone de culasse (210) qui, avec le cylindre (202, 402) et le piston (204, 404) définit un espace de cylindre (212) ; une soupape d'entrée (214) et une soupape de sortie (216) agencées dans l'élément frontal (208) ; un canal d'entrée (218) agencé dans l'élément frontal (208) entre la soupape d'entrée (214) et la zone de culasse (210) ; un canal de sortie (220) agencé dans l'élément frontal (208) entre la zone de culasse (210) et la soupape de sortie (216). Le canal d'entrée (218) et le canal de sortie (220) s'étendent dans une direction sensiblement droite, de sorte que des bulles d'air (234) sont empêchées d'être piégées dans les canaux d'entrée et de sortie (218, 220).
EP11790755.0A 2010-11-30 2011-11-24 Pompe de chromatographie Withdrawn EP2646686A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE1051261 2010-11-30
PCT/EP2011/070953 WO2012072494A1 (fr) 2010-11-30 2011-11-24 Pompe de chromatographie

Publications (1)

Publication Number Publication Date
EP2646686A1 true EP2646686A1 (fr) 2013-10-09

Family

ID=45092341

Family Applications (1)

Application Number Title Priority Date Filing Date
EP11790755.0A Withdrawn EP2646686A1 (fr) 2010-11-30 2011-11-24 Pompe de chromatographie

Country Status (6)

Country Link
US (1) US20130259723A1 (fr)
EP (1) EP2646686A1 (fr)
JP (1) JP2014505194A (fr)
CN (1) CN103221688A (fr)
CA (1) CA2819114A1 (fr)
WO (1) WO2012072494A1 (fr)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102013105445B4 (de) † 2013-05-28 2015-08-20 Pintsch Bubenzer Gmbh Funktionseinheit und Elektrohydraulisches Bremslüftgerät mit einer Solchen
CN106104267B (zh) * 2014-03-31 2020-11-03 安捷伦科技有限公司 高压泵中的随活塞移动的密封件
KR102457681B1 (ko) * 2014-10-13 2022-10-20 알파 에스알엘 유체 제품들을 위한 양변위 펌프 및 펌핑 그룹 및 그의 사용을 위한 방법
CN105443372B (zh) * 2015-11-26 2017-07-14 中国南方电网有限责任公司超高压输电公司广州局 一种双作用直线往复式泵头

Family Cites Families (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2246685A (en) * 1940-03-27 1941-06-24 Clearing Machine Corp Piston packing
DE850995C (de) 1950-11-01 1952-09-29 Albert Ziegler Fa Handpumpe zum Entlueften der Saugleitung einer Motorspritze
US3049082A (en) * 1958-05-26 1962-08-14 John W Mecom Reciprocating pump
US3545897A (en) * 1964-07-08 1970-12-08 Peters & Russell Inc Pump
DE1960369A1 (de) * 1969-12-02 1971-06-09 Siemens Ag Vorrichtung zur Daempfung der Pulsation einer stroemenden Fluessigkeit
DE2940606C2 (de) * 1979-10-06 1985-12-19 Woma-Apparatebau Wolfgang Maasberg & Co Gmbh, 4100 Duisburg Pumpenventilkopf für Hochdruckpumpen
DE3111614A1 (de) * 1981-03-25 1982-10-07 Uhde Gmbh, 4600 Dortmund "ventilsatz fuer hochdruckpumpen"
DE3122091C1 (de) * 1981-06-03 1982-12-16 Saphirwerk, Industrieprodukte AG Nidau, 2560 Nidau Tauchkolbenpumpe
US4467703A (en) * 1982-08-26 1984-08-28 United States Steel Corporation Reciprocable pump
US4527961A (en) * 1982-08-26 1985-07-09 United States Steel Corporation Reciprocable pump having axially pivotable manifold to facilitate valve inspection
US4758135A (en) * 1986-12-30 1988-07-19 Weatherford U.S., Inc. Pump head
US5037277A (en) * 1989-07-26 1991-08-06 Flow International Corporation Poppet valve for a high pressure fluid pump
US5154589A (en) * 1990-11-09 1992-10-13 National Instrument Company Metering pump
US5664938A (en) * 1992-03-05 1997-09-09 Yang; Frank Jiann-Fu Mixing apparatus for microflow gradient pumping
DE19627974C2 (de) * 1996-07-11 2003-02-06 Getrag Getriebe Zahnrad Hydraulische Stelleinheit und Verfahren zum Entlüften einer hydraulischen Stelleinheit
JP3777490B2 (ja) * 1997-01-31 2006-05-24 株式会社荏原製作所 送液装置及びその制御方法
JP4455713B2 (ja) * 2000-02-21 2010-04-21 株式会社島津製作所 弁ユニット及びそれを用いた送液ポンプ
US6623259B1 (en) * 2002-05-06 2003-09-23 George H. Blume High pressure plunger pump housing and packing
US8147227B1 (en) * 2000-07-18 2012-04-03 Blume George H Valve guide and spring retainer assemblies
US6382940B1 (en) * 2000-07-18 2002-05-07 George H. Blume High pressure plunger pump housing and packing
CN1238717C (zh) * 2001-06-29 2006-01-25 中国科学院大连化学物理研究所 低脉动高精度双柱塞高效液相色谱泵
US7684008B2 (en) 2003-06-11 2010-03-23 Asml Netherlands B.V. Lithographic apparatus and device manufacturing method
JP2005133647A (ja) * 2003-10-30 2005-05-26 Ebara Corp アキシアルピストンポンプ又はモータ
DE102004037341C5 (de) * 2004-08-02 2008-06-19 Dionex Softron Gmbh Vorrichtung zum gekühlten Aufbewahren und Abgeben von Proben für eine integrierte Flüssigkeits-Kühleinheit
DE102007050335A1 (de) * 2007-10-18 2009-04-23 Bayer Technology Services Gmbh Anordnung und Verfahren zur Bereitstellung eines vorzugsweise zeitlich veränderlichen Flüssigkeitsgemisches
US8221100B2 (en) * 2008-12-04 2012-07-17 Nlb Corp. High pressure water pump valve and seal structure
JP5533061B2 (ja) * 2009-06-12 2014-06-25 パナソニック株式会社 密閉型圧縮機および冷凍装置
US7950322B2 (en) * 2009-10-09 2011-05-31 Vicars Berton L Plunger assembly

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2012072494A1 *

Also Published As

Publication number Publication date
JP2014505194A (ja) 2014-02-27
WO2012072494A1 (fr) 2012-06-07
CA2819114A1 (fr) 2012-06-07
CN103221688A (zh) 2013-07-24
US20130259723A1 (en) 2013-10-03

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