EP0132913B1 - Pompe à membrane ou à piston - Google Patents

Pompe à membrane ou à piston Download PDF

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Publication number
EP0132913B1
EP0132913B1 EP84302390A EP84302390A EP0132913B1 EP 0132913 B1 EP0132913 B1 EP 0132913B1 EP 84302390 A EP84302390 A EP 84302390A EP 84302390 A EP84302390 A EP 84302390A EP 0132913 B1 EP0132913 B1 EP 0132913B1
Authority
EP
European Patent Office
Prior art keywords
diaphragms
chambers
pump
valve
partition member
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP84302390A
Other languages
German (de)
English (en)
Other versions
EP0132913A1 (fr
Inventor
Derek Noel Marchant
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.)
FLOTRONICS AG
Original Assignee
FLOTRONICS AG
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 FLOTRONICS AG filed Critical FLOTRONICS AG
Priority to AT84302390T priority Critical patent/ATE31966T1/de
Publication of EP0132913A1 publication Critical patent/EP0132913A1/fr
Application granted granted Critical
Publication of EP0132913B1 publication Critical patent/EP0132913B1/fr
Expired legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B43/00—Machines, pumps, or pumping installations having flexible working members
    • F04B43/02—Machines, pumps, or pumping installations having flexible working members having plate-like flexible members, e.g. diaphragms
    • F04B43/06—Pumps having fluid drive
    • F04B43/073—Pumps having fluid drive the actuating fluid being controlled by at least one valve
    • F04B43/0736—Pumps having fluid drive the actuating fluid being controlled by at least one valve with two or more pumping chambers in parallel

Definitions

  • the invention relates to pumps and has a particularly useful but not exclusive application in pumps of the kind known as double diaphragm pumps.
  • U.S. Specification No. 4334837 discloses a pump comprising a hollow casing closed at its ends, two diaphragms disposed within the casing and generally parallel to each other adjacent the respective end portions of the casing, each diaphragm forming with its adjacent end portion of the casing a closed first chamber, a fixed internal partition member disposed between the diaphragms and forming two closed second chambers with the respective diaphragms, said second chambers having inlets thereto controlled by respective valves and outlets therefrom controlled by respective valves, a push rod extending in a sealing manner through the partition member to transmit axial displacing forces between the diaphragms, and valve means actuated in dependence on the position of the diaphragms and adapted to open passages for connecting each of the two first chambers alternately to a source of pressure fluid and to exhaust, thereby to cause the push rod and diaphragms to reciprocate in unison and to cause the diaphragms to operate the
  • the two ends of said push rod are in abutting relationship with but are not connected to the two diaphragms or pistons respectively.
  • inlet passages providing the inlets to said second chambers and outlet passages providing the outlets from said second chambers are formed in the partition chamber.
  • said inlet passages are constituted by branch passages extending from a common inlet opening in the casing
  • said outlet passages providing the outlets from said second chambers are constituted by branch passages extending from a common outlet opening in the casing, the valves associated with second chambers being mounted in the branch passages.
  • said end portions of the casing are formed by respective end members which are detachably secured to the partition member, and the two diaphragms or pistons are respectively removably attached at their peripheries to the adjacent end members.
  • diaphragms may have a reinforcing plate embedded in the central region thereof.
  • the pump has an external casing formed by a hollow cylindrical support ring 10 to opposite ends of which end covers 11,12 are secured by tie bolts or, where frequent cleaning of the pump is necessary, quick- release clamps.
  • Two diaphragms 16, 17 having a peripheral bead 18 are respectively clamped between opposite axial ends of the support ring 13 and partition member 14 at one side and the two end covers 11, 12 at the other side.
  • the bead 18 itself is accommodated in channel section grooves in the support ring and the end cover.
  • the groove in the end cover may have a dovetail section (not shown) and the bead may have a correspondingly shaped portion which engages in the groove and serves to attach the diaphragm removably to the adjacent end cover.
  • Each diaphragm 16,17 divides the space between the adjacent end cover 11, 12 and the partition member 14 into two chambers 19, 20.
  • the two axially outer chambers 19 constitute motor chambers and the two axially inner chambers 20 constitute pumping chambers.
  • Each diaphragm has its central region stiffened by a reinforcing disc 21 embedded in the diaphragm material and a push rod 22 which is a sliding sealing fit in two sealing rings 23 in the partition member has its ends in abutment with the two diaphragms respectively in operation of the pump.
  • a bush extending over the full axial length of the aperture in the partition member may be used instead of rings 23 if desired.
  • the partition member has formed in it two bifurcated passages 25, 26 serving respectively as inlets and outlets respectively for the pumped fluid, and each of the branches of each passage incorporates a non-return valve.
  • the two branches of the inlet passage are shown at 25a and 25b and extend from a common inlet atthe outer periphery of the partition member 14 to the two pumping chambers 20 respectively.
  • Each of the branches has mounted in it a valve seating element 28 and a captive ball 29 together constituting the non-return valve.
  • the two branches 26a, 26b of the outlet passage extend from the respective pumping chambers 20 to a common outlet at the periphery of the partition member, and each branch incorporates a valve seating element 28 and a captive ball 29 constituting the non-return valve.
  • the partition member 14 is made in one piece from a plastics material such as PTFE and each seating element 28 is pressed into place through a chordal aperture 28a in the member 14 and comprises a portion 28b which blanks off the aperture 28a and a portion 28c which provides a seat for the captive ball 29.
  • the inner face of portion 28b has an arch-like projecting rib 28d the limbs of which serve with the opposite wall of the passage to guide the ball for rectilinear movement.
  • the partition member is made in two halves which are clamped together axially between end covers and valve seating rings are located in grooves on the axially inner surfaces of the two halves.
  • the partition member is located with the common inlet and the common outlet in circumferential alignment with radial apertures in the diaphragm ring 13 by two axial pins 13a, and a liner in the form of a hollow bolt 30 extends through each of these apertures and an aligned aperture in the support ring 10, the head of the bolt being countersunk in the diaphragm ring 13 and the shank of the bolt being in screw-threaded engagement in the aperture in the support ring.
  • a jointing boss extends about the outer end of each of these apertures in the support ring 10.
  • An air-supply/exhaust passage 40 shown in Figure 3A is formed in each end cover 11, 12 through which compressed air is admitted to and exhausted from the associated motor chamber 19 by way of a servo valve 39.
  • each end cover In the outer end of a bore extending centrally through each end cover is secured a pilot valve unit 33 which is screw-threaded into the end cover and which carries a pilot valve member 34 loaded lightly into sealing engagement with a valve seat 35 by a compression spring 36.
  • An intermediate enlarged portion of the bore forms a chamber 38 about the unit and each of the chambers communicates through a passage 41 with an associated pilot chamber 37 of a pneumatic servo changeover valve 39.
  • This valve (see Figure 3A) is of the kind comprising a valve body 42 having a bore in which a valve spool 44 is slidably mounted.
  • the chambers 37 at opposite ends of the spool are in permanently open but restricted communication with a source of compressed air through passages 45.
  • Electric solenoid devices may be provided which control movements of the spool valve member in both directions independently, similarly electric solenoid devices may be provided which control movements of the spool valve in both directions independently and which are also capable of moving the spool valve member into either of its end positions from a central position into which it is urged by centralising springs provided in the end chambers; in this case, the valve ports and lands are arranged so that both motor chambers 19 are connected to exhaust when the spool valve member is in its central position.
  • the ends of the push rod 22 are flat but may be suitably domed and profiled to avoid pressing sharp edges against the diaphragms whatever the attitude of the latter.
  • the diaphragms themselves may be made from any suitable materials, including PTFE, rubber, neoprene, viton and PTFE-faced rubber, and may be reinforced locally or across the full face of the diaphragm if required.
  • the diaphragms may be of the tandem or double-skin type with a liquid held captive between the two skins to transmit the pressures from one skin to the other, and a device responsive to the pressure of the liquid and/or to a change in the composition of the liquid may be provided to indicate rupture of one of the skins.
  • the partition member and the bolts 30 may be made from stainless steel, plastics, glass, wood or any material suitably resistant to corrosive properties of the fluid to be pumped, and it will be apparent that the diaphragms 16, 17 prevent leakage of the pumped fluid between the partition member 14 and the bolts 30, so that these five components jointly confine the pumped fluid during the whole of its passage through the pump.
  • Flap valves may be employed in place of the ball valves and may advantageously be arranged so as to enable the pumped fluid to enter by the top passage 26 and be delivered through the bottom passage 25.
  • a major advantage of the illustrated pump is that it enables dangerous or unpleasant fluids to be pumped with relative safety in that the partition member 14 can be made of plastics, glass or wood or any other material which in itself is relatively fragile but which is appropriately resistant to the effects of the fluid, because the partition member is protected by the support ring and the end covers against accidental damage.
  • the partition member 14 can be made of plastics, glass or wood or any other material which in itself is relatively fragile but which is appropriately resistant to the effects of the fluid, because the partition member is protected by the support ring and the end covers against accidental damage.
  • the pumping chambers are at opposite ends of the pump and the air chambers are adjacent each other, and a pneumatic switching mechanism is disposed between the diaphragm and is consequently difficult of access, but in the illustrated pump the pneumatic switching mechanism can be conveniently mounted in the casing to be readily accessible and removable for servicing.
  • the air chambers are at the ends of the pump, the rod 22 extending between the diaphragm is never in tension and is therefore not connected to the diaphragms.
  • the diaphragms can be unperforated and the simple abutment contact between the rod and the diaphragm allows the latter to find their natural position during pumping.
  • the length of the working stroke can be adjusted by altering the length of the pilot valve member 38 projecting into the cylinder.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Reciprocating Pumps (AREA)
  • Saccharide Compounds (AREA)
  • Fluid-Driven Valves (AREA)

Claims (11)

1. Pompe comportant un corps creux fermé à ses extrémités; deux diaphragmes (16, 17) ou pistons disposés à l'intérieur du corps et, d'une manière générale, parallèlement l'un à l'autre, à proximité de la partie d'extrémité correspondante du corps, chaque diaphragme (16, 17) ou piston formant, avec la partie d'extrémité du corps qui lui est adjacente, une première chambre fermée (19); un organe de séparation interne fixe (14) disposé entre les diaphragmes ou pistons et formant, avec les diaphragmes ou pistons correspondants, deux secondes chambres fermées (20), lesdites secondes chambres comportant des admissions commandées par des vannes respectives, et des évacuations commandées par des vannes respectives; une tige-poussoir (22) qui s'étend d'une manière étanche à travers l'organe de séparation (14) pour transmettre des forces de déplacement axial entre les diaphragmes ou pistons; et des moyens formant vannes (33, 39) actionnés en fonction de la position des diaphragmes ou pistons et adaptés pour ouvrir des passages destinés à relier chacune des deux premières chambres (19) à une source de fluide sous pression et à un échappement, alternativement, pour ainsi contraindre la tige-poussoir (22) et les diaphragmes ou pistons à aller et venir d'une manière synchronisée et obliger les diaphragmes ou pistons à faire fonctionner les secondes chambres (20) comme des chambres de pompage; caractérisée en ce que les deux extrémités de la tige-poussoir (22) sont dans une relation en butée avec les diaphragmes (16, 17) ou pistons, mais ne sont pas reliées à ceux-ci.
2. Pompe telle que définie dans la revendication 1, caractérisée en ce que des passages d'admission (25) assurant les admissions dans lesdites secondes chambres, et des passages d'évacuation (26) assurant les évacuations hors desdites secondes chambres (20) sont ménagés dans l'organe de séparation (14).
3. Pompe telle que définie dans la revendication 2, caractérisée en ce que lesdits passages d'admission (25) sont constitués par des passages ramifiés (25a, 25b) qui s'étendent depuis un orifice d'admission commun ménagé dans le corps, et en ce que lesdits passages d'évacuation (26) assurant les évacuations hors desdites secondes chambres (20) sont constitués par des passages ramifiés (26a, 26b) qui s'étendent depuis un orifice d'évacuation commun ménagé dans le corps, les vannes associées à ces secondes chambres étant montées dans les passages ramifiés.
4. Pompe telle que définie dans l'une quelconque des revendications 1 à 3, caractérisée en ce que lesdites parties d'extrémité du corps sont formées par des organes d'extrémité (11, 12) respectifs, fixés d'une manière amovible à l'organe de séparation (14), et en ce que les deux diaphragmes (16, 17) ou pistons sont, au niveau de leurs périphéries, respectivement fixés d'une manière amovible aux organes d'extrémité (11, 12) adjacents.
5. Pompe telle que définie dans l'une quelconque des revendications 1 à 4, caractérisée en ce que l'organe de séparation interne (14) se compose de deux moitiés qui viennent en butée l'une contre l'autre axialement.
6. Pompe telle que définie dans l'une quelconque des revendications 1 à 5, caractérisée en ce que chacune desdites vannes comporte une bille (29) montée en vue d'un mouvement rectiligne libre, mais guidé, pour s'engager dans un siège de vanne annulaire (28) et se dégager de celui-ci, afin de jouer le rôle d'une soupape de non-retour.
7. Pompe telle que définie dans la revendication 6 en combinaison avec la revendication 5, caractérisée en ce que lesdits sièges de vanne (28) sont constitués par des pièces d'insertion annulaires disposées entre les deux moitiés de l'organe de séparation (14).
8. Pompe telle que définie dans l'une quelconque des revendications 1 à 5, caractérisée en ce que l'une au moins desdites vannes est une soupape à clapet.
9. Pompe telle que définie dans l'une quelconque des revendications 1 à 8, caractérisée en ce que lesdits moyens formant vannes (33, 39) comportent une vanne pilote (34) montée dans chacune des parties d'extrémité, laquelle vanne pilote est ouverte par la vanue en butée contre elle du diaphragme (16,17) adjacent, à la fin d'une course de la pompe, et opère pour ouvrir une ligne sous pression asservie (41) extérieure, en direction d'un échappement.
10. Pompe telle que définie dans la revendication 9, en combinaison avec une servovanne (39) comportant une bague de vanne disposée à coulissement dans une boîte de vanne (42), des extrémités opposées de la bague étant disposées de manière à recevoir de l'air sous pression par l'intermédiaire de passages restreints (45), ouverts en permanence, et ayant des raccordements d'échappement respectivement commandés par les deux vannes pilotes (34), ladite boîte définissant des orifices d'admission et d'évacuation commandés par la bague de vanne pour fournir de l'air comprimé provenant de ladite admission, à ladite première chambre (19), alternativement, et pour relier à l'échappement (48) la chambre qui n'est pas en train d'être alimentée en air comprimé.
11. Combinaison telle que définie dans la revendication 10, dans laquelle la servovanne (39) possède des moyens de commande électriques aptes à opérer pour retarder des mouvements de permutation de la bague de vanne, amorcés par un actionnement des vannes pilotes (34).
EP84302390A 1983-04-07 1984-04-06 Pompe à membrane ou à piston Expired EP0132913B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT84302390T ATE31966T1 (de) 1983-04-07 1984-04-06 Membran- oder kolbenpumpe.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB8309426 1983-04-07
GB838309426A GB8309426D0 (en) 1983-04-07 1983-04-07 Pumps

Publications (2)

Publication Number Publication Date
EP0132913A1 EP0132913A1 (fr) 1985-02-13
EP0132913B1 true EP0132913B1 (fr) 1988-01-13

Family

ID=10540757

Family Applications (1)

Application Number Title Priority Date Filing Date
EP84302390A Expired EP0132913B1 (fr) 1983-04-07 1984-04-06 Pompe à membrane ou à piston

Country Status (4)

Country Link
EP (1) EP0132913B1 (fr)
AT (1) ATE31966T1 (fr)
DE (1) DE3468727D1 (fr)
GB (1) GB8309426D0 (fr)

Families Citing this family (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5053941A (en) * 1986-08-29 1991-10-01 Sun Microsystems, Inc. Asynchronous micro-machine/interface
GB8713668D0 (en) * 1987-06-11 1987-07-15 Flotronics Ag Double-diaphragm pumps
IT1223054B (it) * 1987-11-04 1990-09-12 O D L Srl Pompa per il trasferimento di liquidi in particolare di birra o di bevande gasate
AU2014895A (en) * 1994-07-18 1996-02-01 Outboard Marine Corporation Fuel system for fuel injected two stroke engine
SE503552C2 (sv) * 1995-04-27 1996-07-01 Svante Bahrton Dubbelverkande pump
WO1996034202A1 (fr) * 1995-04-27 1996-10-31 Svante Bahrton Pompe a double effet
SE9704160L (sv) * 1997-11-13 1999-05-14 Svante Bahrton Ventilanordning
GB9930809D0 (en) 1999-12-30 2000-02-16 Flotronic Pumps Limited Double-diaphragm pumps
GB2470348B (en) 2009-04-29 2011-06-08 Flotronic Pumps Ltd Double-diaphragm pump with unidirectional valve arrangement
ES2380260B2 (es) * 2010-05-18 2013-02-14 Samoa Industrial S.A. Bomba de doble membrana de flujo central
US10477883B2 (en) 2015-08-25 2019-11-19 Cornelius, Inc. Gas injection assemblies for batch beverages having spargers
US10785996B2 (en) 2015-08-25 2020-09-29 Cornelius, Inc. Apparatuses, systems, and methods for inline injection of gases into liquids
CN107013442A (zh) * 2016-03-02 2017-08-04 上海方顿工业设备有限公司 一种外置气控阀的气动隔膜泵
US11040314B2 (en) 2019-01-08 2021-06-22 Marmon Foodservice Technologies, Inc. Apparatuses, systems, and methods for injecting gasses into beverages
CN113090491A (zh) * 2021-05-06 2021-07-09 蓝工(江苏)环境系统有限公司 一种新型高效激光驱动式微型压缩机

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1920014A (en) * 1931-06-26 1933-07-25 Trico Products Corp Multiple diaphragm pump
GB481270A (en) * 1936-10-07 1938-03-08 Ettore Caretta Improved diaphragm pump with direct actuation by fluid
US2260306A (en) * 1938-04-16 1941-10-28 Sullivan Machinery Co Pump
GB837737A (en) * 1957-12-06 1960-06-15 Wm Butler & Co Bristol Ltd Improvements relating to hydraulically operated pumps
JPS6010189B2 (ja) * 1979-01-19 1985-03-15 アイシン精機株式会社 ダイヤフラム式エアポンプ装置
US4386888A (en) * 1980-09-29 1983-06-07 Mccann's Engineering And Manufacturing Company Double diaphragm operated reversing valve pump

Also Published As

Publication number Publication date
GB8309426D0 (en) 1983-05-11
EP0132913A1 (fr) 1985-02-13
ATE31966T1 (de) 1988-01-15
DE3468727D1 (en) 1988-02-18

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