EP1972783B1 - Dispensing pump with an isolating membrane of one of its walls or end flange of the dispensing chamber - Google Patents

Dispensing pump with an isolating membrane of one of its walls or end flange of the dispensing chamber Download PDF

Info

Publication number
EP1972783B1
EP1972783B1 EP08290218A EP08290218A EP1972783B1 EP 1972783 B1 EP1972783 B1 EP 1972783B1 EP 08290218 A EP08290218 A EP 08290218A EP 08290218 A EP08290218 A EP 08290218A EP 1972783 B1 EP1972783 B1 EP 1972783B1
Authority
EP
European Patent Office
Prior art keywords
pump
sheet
fluid
chamber
side plate
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 - Fee Related
Application number
EP08290218A
Other languages
German (de)
French (fr)
Other versions
EP1972783A1 (en
Inventor
Rémy Lefebvre
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.)
Milton Roy Europe SA
Original Assignee
Milton Roy Europe SA
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 Milton Roy Europe SA filed Critical Milton Roy Europe SA
Publication of EP1972783A1 publication Critical patent/EP1972783A1/en
Application granted granted Critical
Publication of EP1972783B1 publication Critical patent/EP1972783B1/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

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
    • F04B15/00—Pumps adapted to handle specific fluids, e.g. by selection of specific materials for pumps or pump parts
    • F04B15/04—Pumps adapted to handle specific fluids, e.g. by selection of specific materials for pumps or pump parts the fluids being hot or corrosive
    • 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
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
    • F05C2225/00—Synthetic polymers, e.g. plastics; Rubber
    • F05C2225/04—PTFE [PolyTetraFluorEthylene]

Definitions

  • the invention relates to a pump for the dosing of an extremely corrosive product.
  • Such a pump conventionally comprises a pump head which defines a pumping chamber, that is to say a variable volume chamber by deformation or displacement of a wall of the head.
  • This chamber is secured to a frame that supports the pump head and the driving members coupled to the movable or deformable wall.
  • the aggressiveness of the pumped fluid leads to the use of noble materials for the parts in contact with the fluid: stainless steels, special alloys, titanium, etc. which are particularly expensive.
  • the most common structure of a pump head consists of a thick disk-shaped piece, hollowed out to define a concave cap that forms the pumping chamber on which the valve boxes are implanted. This cap is closed by the membrane, pinched between the workpiece and the frame of the pump.
  • the hollow part is a part that offers a large surface in contact with the pumped fluid. It is also a massive piece that, when it must be made of highly chemically unassailable material, is extremely expensive.
  • the coating of the surface of this part turned towards the pumping chamber by means of either a kind of vulcanization (cf. US2,753,804 ) or by a kind of skin, for example polyethylene tetrafluoride formed by molding and held by clipping into the pumping chamber (see US 3,000,320 ).
  • the preamble of independent claim 1 is based on the document US 3000,320 .
  • the invention proposes to solve the question of the passivation of this surface exposed to the pumped fluid, by proposing a coating of this surface by means of a skin perfectly coapted to the shape of the surface to be protected so that no degradation of mechanical origin or as a result of fatigue over time, can not affect this protection.
  • the subject of the invention is therefore a pump, in particular for chemically reactive fluid, in which a pump head comprises at least two walls between which is defined a pumping chamber for the fluid in question, one of the walls being fixed, the other being movable or deformable with respect to the fixed wall by means of a driving or deformation device, the at least one fixed wall being provided with a protective coating with respect to the fluid, characterized in that the coating consists of by a sheet of plastic material, sealingly pressed against the surface at the periphery thereof, the space between the protected surface and the covering sheet, within the line of their sealing contact being filled with an incompressible liquid.
  • the composite material formed of the liquid and the plastic sheet is a non-deformable material under the effect of alternating pressures and depressions that prevail in the chamber. Indeed, the liquid having completely filled the space between the surface and the sheet has chased away any bubble of gas which could, by its compressibility and therefore the variation of its volume, leave a freedom of deformation to the sheet with respect to the wall which it protects, deformation which would have reduced the cubic capacity of the pump and which would have constituted a stress of fatigue of the sheet leading quickly to its tearing.
  • This surface resistance can be imparted to the sheet in at least two different ways.
  • the first is to conform the sheet substantially spherical or conical cap, in congruence with the inner surface of the flange to marry it as accurately as possible, with the convexity of this shape facing the interior of the chamber.
  • the second is to set up a protective plate of the surface of the sheet turned on the side of the pumping chamber, protective plate of noble material having good corrosion resistance.
  • the pump is finally equipped with means for proceeding in a simple and correct way to the mounting of the protective sheet, either at the time of initial assembly of the pump, or at the time of reassembly thereof after regular maintenance operations.
  • These are two orifices which is equipped with the flange, opening in the immediate vicinity of the sealing line between the sheet and the pump head, one in the lowest part and the other in the most important part. top of the pumping chamber, each having a threaded plug for closure.
  • a protective cap of the cap covers each of them and rests on an outer surface of the flange by a bearing face having a sealing O-ring surrounding the plug and housed in a conical bottom groove, allowing the radial expansion of this seal under the effect of a fluid under pressure from the cap and the creation of a leakage of this fluid between the cover and the flange.
  • the pump head shown in figure 1 comprises, in known manner, a cylindrical ring 1 on the left flank of which is reported a flange 2, in the form of solid disc, by means of peripheral screws not shown while its right side is attached to a pump frame 3 which in closes and supports all the motor organs of this one.
  • a deformable membrane 4 is clamped between the crown and the frame.
  • the pumping chamber 5 is thus delimited by the ring 1, the flange 2 and the membrane 4.
  • a valve box 6 constitutes the connection means of the pumping chamber 5 to a suction pipe, not shown, through at least one unidirectional valve passing from the direction A.
  • the discharge of the pump also comprises a valve box 7 with a unidirectional valve whose tail 8 is seen, also passing in the direction A.
  • the membrane 4 is driven by a race suction in the direction B and a discharge stroke in the direction C by means of a hydraulic fluid contained in a chamber of Work 9 which also includes a conventional device 10 for compensating leaks.
  • the flange 2 is pierced with two orifices 22 and 23 which open into the chamber 5, for the one 22, in the lower part of the chamber at the boundary of the zone Z and for the other, in the upper part of the chamber, also at the edge of the zone Z. It is thus possible to introduce between the sheet 20 and the flange 2 a film of incompressible liquid, for example oil from the lower orifice 22.
  • the liquid is forced by means of a pump into this space so as to cause progressive invasion until it comes out of the The upper orifice 23. It is thus certain to have driven out all the interstitial air that remained between the sheet and the flange. These openings are then plugged.
  • the pump is then able to operate without loss of displacement and without mechanical stress and fatigue for the sheet 20.
  • the lower orifice 22 is adapted to receive a threaded plug provided with an O-ring seal 31 and a central channel 32 which opens through a transverse channel 32a in a section 22a of the orifice 22.
  • This section communicates with the final section 22b of this orifice 22 through a seat (shrink) 22c which can be closed by the conical end 30a of the threaded cap 30.
  • the free end of this plug has a six maneuvering faces 30b surmounted by a fir-tail connecting end 30c for the temporary connection of the orifice 22 to a source of pressurized fluid not shown.

Landscapes

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

Description

L'invention concerne une pompe pour le dosage d'un produit extrêmement corrosif.The invention relates to a pump for the dosing of an extremely corrosive product.

ARRIERE PLAN DE L'INVENTION.BACKGROUND OF THE INVENTION

Une telle pompe comporte de manière classique une tête de pompe qui définit une chambre de pompage, c'est-à-dire une chambre à volume variable par déformation ou déplacement d'une paroi de la tête. Cette chambre est solidaire d'un bâti qui supporte la tête de pompe et les organes moteurs attelés à la paroi mobile ou déformable.Such a pump conventionally comprises a pump head which defines a pumping chamber, that is to say a variable volume chamber by deformation or displacement of a wall of the head. This chamber is secured to a frame that supports the pump head and the driving members coupled to the movable or deformable wall.

Quand cette paroi est un piston, les organes moteurs sont formés par un embiellage reliant le piston à un vilebrequin à excentrique unique. Quand cette paroi est une membrane, ce qui est le cas principalement concerné par l'invention, les organes moteurs sont soit une transmission mécanique directe du genre embiellage, soit une transmission hydraulique avec une chambre de travail d'un côté de la membrane pleine d'un fluide hydraulique animé d'un mouvement cyclique par un piston moteur qui pousse ce fluide vers la membrane, sous pression, en diminuant le volume de la chambre de pompage, (refoulement de la pompe) ou qui l'aspire en déplaçant la membrane en sens inverse, donc en augmentant le volume de la chambre de pompage (aspiration de la pompe).When this wall is a piston, the drive members are formed by a linkage connecting the piston to a single eccentric crankshaft. When this wall is a membrane, which is the case mainly concerned by the invention, the drive members are either a direct mechanical transmission of the type linkage, or a hydraulic transmission with a working chamber on one side of the membrane full of a hydraulic fluid driven by a cyclic movement by a motor piston which pushes this fluid towards the membrane, under pressure, by reducing the volume of the pumping chamber (pump discharge) or by sucking it by moving the membrane in the opposite direction, thus increasing the volume of the pumping chamber (suction of the pump).

La tête de pompe comporte un orifice d'admission et un orifice de refoulement, chacun pourvu d'au moins un clapet unidirectionnel de sorte que le fluide circule dans un seul sens dans la chambre de pompage. Les clapets sont maintenus solidaires mais démontables de la tête de pompe par des boîtes à clapets.The pump head has an inlet port and a discharge port, each provided with at least one unidirectional valve so that the fluid flows in a single direction in the pumping chamber. The valves are held together but removable from the pump head by valve boxes.

L'agressivité du fluide pompé conduit à l'emploi de matériaux nobles pour les pièces en contact avec le fluide: aciers inoxydables, alliages spéciaux, titane, etc. qui sont particulièrement coûteux.The aggressiveness of the pumped fluid leads to the use of noble materials for the parts in contact with the fluid: stainless steels, special alloys, titanium, etc. which are particularly expensive.

La structure la plus fréquente d'une tête de pompe consiste en une pièce en forme de disque épais, creusée pour définir une calotte concave qui forme la chambre de pompage sur laquelle sont implantées les boîtes à clapets. Cette calotte est refermée par la membrane, pincée entre la pièce et le bâti de la pompe.The most common structure of a pump head consists of a thick disk-shaped piece, hollowed out to define a concave cap that forms the pumping chamber on which the valve boxes are implanted. This cap is closed by the membrane, pinched between the workpiece and the frame of the pump.

La pièce creusée est une pièce qui offre une surface importante au contact du fluide pompé. C'est en outre une pièce massive qui, lorsqu'il faut la réaliser en matériau hautement inattaquable chimiquement, revient extrêmement cher.The hollow part is a part that offers a large surface in contact with the pumped fluid. It is also a massive piece that, when it must be made of highly chemically unassailable material, is extremely expensive.

On a pensé au revêtement de la surface de cette pièce tournée vers la chambre de pompage au moyen, soit d'une sorte de vulcanisation (voir US2 753 804 ) soit par une sorte de peau, par exemple en polytétrafluorure d'éthylène mise en forme par moulage et retenue par clipage dans la chambre de pompage (voir US 3 000 320 ).The coating of the surface of this part turned towards the pumping chamber by means of either a kind of vulcanization (cf. US2,753,804 ) or by a kind of skin, for example polyethylene tetrafluoride formed by molding and held by clipping into the pumping chamber (see US 3,000,320 ).

Le préambule de la revendication indépendante 1 est basé sur le document US 3000 320 .The preamble of independent claim 1 is based on the document US 3000,320 .

Aucune de ces solutions ne convient : la première parce qu'il n'existe aucune matière chimiquement neutre qui puisse former un revêtement solidement attaché par collage ou tout autre procédé d'adhésion surfacique en regard des contraintes de pression dépression existant dans une chambre de pompage, la seconde parce qu'il n'est pas possible de résister à ces contraintes par un seul agrafage d'une peau à un corps de tête de pompage. En outre pour ce dernier cas de figure, la conformation de la peau par moulage par exemple, ne peut ni être parfaitement congruente avec la surface du corps exposée dans la chambre de pompage, ni être suffisamment régulière pour qu'il n'existe pas des poches de gaz entre le corps et la peau qui se dilatent et se contractent à chaque cycle de pompage, diminuant la cylindrée de cette pompe.None of these solutions is appropriate: the first because there is no chemically neutral material that can form a firmly bonded coating by bonding or any other method of adhesion surface against vacuum pressure constraints existing in a pumping chamber the second because it is not possible to resist these constraints by a single stapling of a skin to a pumping head body. Furthermore, for the latter case, the conformation of the skin by molding, for example, can neither be perfectly congruent with the surface of the body exposed in the pumping chamber nor be sufficiently regular. so that there are no pockets of gas between the body and the skin that expand and contract each pump cycle, decreasing the displacement of this pump.

L'invention se propose de résoudre la question de la passivation de cette surface exposée au fluide pompé, en proposant un revêtement de cette surface au moyen d'une peau parfaitement coaptée à la forme de la surface à protégée de manière qu'aucune dégradation d'origine mécanique ou par suite d'une fatigue au fil du temps, ne puisse affecter cette protection.The invention proposes to solve the question of the passivation of this surface exposed to the pumped fluid, by proposing a coating of this surface by means of a skin perfectly coapted to the shape of the surface to be protected so that no degradation of mechanical origin or as a result of fatigue over time, can not affect this protection.

BREVE DESCRIPTION DE L'INVENTIONBRIEF DESCRIPTION OF THE INVENTION

L'invention a donc pour objet une pompe notamment pour fluide chimiquement réactif, dans laquelle une tête de pompe comporte au moins deux parois entre lesquelles est définie une chambre de pompage du fluide considéré, l'une des parois étant fixe, l'autre étant mobile ou déformable par rapport à la paroi fixe au moyen d'un dispositif d'entraînement ou de déformation, la paroi fixe au moins étant pourvue d'un revêtement de protection à l'égard du fluide, caractérisée en ce que le revêtement est constitué par une feuille en matière plastique, plaquée de manière étanche contre la surface à la périphérie de celle-ci, l'espace compris entre la surface protégée et la feuille de revêtement, à l'intérieur de la ligne de leur contact étanche étant rempli d'un liquide incompressible.The subject of the invention is therefore a pump, in particular for chemically reactive fluid, in which a pump head comprises at least two walls between which is defined a pumping chamber for the fluid in question, one of the walls being fixed, the other being movable or deformable with respect to the fixed wall by means of a driving or deformation device, the at least one fixed wall being provided with a protective coating with respect to the fluid, characterized in that the coating consists of by a sheet of plastic material, sealingly pressed against the surface at the periphery thereof, the space between the protected surface and the covering sheet, within the line of their sealing contact being filled with an incompressible liquid.

Le matériau composite formé du liquide et de la feuille de matière plastique constitue un matériau indéformable sous l'effet des pressions et dépressions alternées qui règnent dans la chambre. En effet, le liquide ayant rempli totalement l'espace entre la surface et la feuille a chassé toute bulle de gaz qui aurait pu, par sa compressibilité donc la variation de son volume, laisser une liberté de déformation à la feuille par rapport à la paroi qu'elle protège, déformation qui aurait amoindri la cylindrée de la pompe et qui aurait constitué une contrainte de fatigue de la feuille conduisant rapidement à son déchirement.The composite material formed of the liquid and the plastic sheet is a non-deformable material under the effect of alternating pressures and depressions that prevail in the chamber. Indeed, the liquid having completely filled the space between the surface and the sheet has chased away any bubble of gas which could, by its compressibility and therefore the variation of its volume, leave a freedom of deformation to the sheet with respect to the wall which it protects, deformation which would have reduced the cubic capacity of the pump and which would have constituted a stress of fatigue of the sheet leading quickly to its tearing.

Cette disposition présente en outre un grand intérêt au niveau de la fabrication. En effet, on sait que par usinage courant, on ne peut pas obtenir un état de surface extrêmement poli de la surface du flasque. En outre, il est impossible de maîtriser la forme de la feuille (par exemple en calotte sphérique) avec les procédés de fabrication connus. Il existera toujours des irrégularités de courbures qui formeront des bosses et des creux en regard de la surface du flasque donc des poches de gaz, surtout si les dimensions de la pompe sont importantes (300 à 450 mm de diamètre extérieur de la tête de pompe par exemple). L'invention permet de s'affranchir de la nécessité de maîtriser avec précision les formes et les états de surfaces des flasque et feuille. Elle autorise donc une fabrication bon marché.This arrangement is also of great interest at the level of manufacture. Indeed, it is known that by current machining, it is not possible to obtain an extremely polished surface state of the surface of the flange. In addition, it is impossible to control the shape of the sheet (for example spherical cap) with the known manufacturing processes. There will always be irregularities of curvature which will form bumps and hollows facing the surface of the flange and therefore pockets of gas, especially if the dimensions of the pump are important (300 to 450 mm outside diameter of the pump head by example). The invention eliminates the need to accurately control the shapes and surface conditions of the flange and sheet. It allows cheap manufacturing.

Par ailleurs, plus la résistance à un allongement surfacique de la feuille de protection est grande, et moins le liquide sera sensible aux variations de pression dans la chambre de pompage. En conséquence, les zones d'étanchéité seront moins sollicitées et les risques de fuite, même au travers de joints ou clapets d'excellente qualité, seront moindres, avec comme avantage une plus longue longévité de la pompe.Furthermore, the greater the resistance to a surface elongation of the protective sheet is large, and the less the liquid will be sensitive to pressure variations in the pumping chamber. Consequently, the sealing zones will be less stressed and the risks of leakage, even through joints or valves of excellent quality, will be lower, with the advantage of a longer service life of the pump.

Cette résistance surfacique peut être conférée à la feuille d'au moins deux manières différentes.
La première consiste à conformer la feuille en calotte sensiblement sphérique ou conique, en congruence avec la surface interne du flasque pour l'épouser le plus exactement possible, avec la convexité de cette forme tournée vers l'intérieur de la chambre.This surface resistance can be imparted to the sheet in at least two different ways.
The first is to conform the sheet substantially spherical or conical cap, in congruence with the inner surface of the flange to marry it as accurately as possible, with the convexity of this shape facing the interior of the chamber.

La seconde consiste à mettre en place une plaque de protection de la surface de la feuille tournée du côté de la chambre de pompage, plaque de protection en matériau noble présentant une bonne résistance à la corrosion.
La pompe est enfin équipée des moyens pour procéder de manière simple et correcte au montage de la feuille de protection, soit au moment de l'assemblage initial de la pompe, soit au moment des remontages de celle-ci après des opérations régulières de maintenance. Il s'agit de deux orifices dont est équipé le flasque, débouchant à proximité immédiate de la ligne d'étanchéité entre la feuille et la tête de pompe, l'un dans la partie la plus basse et l'autre dans la partie la plus haute de la chambre de pompage, chacun comportant un bouchon fileté pour sa fermeture. Un capot de protection du bouchon recouvre chacun d'eux et repose sur une surface externe du flasque par une face d'appui comportant un joint torique d'étanchéité entourant le bouchon et logé dans une gorge à fond conique, permettant la dilatation radiale de ce joint sous l'effet d'un fluide sous pression issu du bouchon et la création d'une fuite de ce fluide entre le capot et le flasque.The second is to set up a protective plate of the surface of the sheet turned on the side of the pumping chamber, protective plate of noble material having good corrosion resistance.
The pump is finally equipped with means for proceeding in a simple and correct way to the mounting of the protective sheet, either at the time of initial assembly of the pump, or at the time of reassembly thereof after regular maintenance operations. These are two orifices which is equipped with the flange, opening in the immediate vicinity of the sealing line between the sheet and the pump head, one in the lowest part and the other in the most important part. top of the pumping chamber, each having a threaded plug for closure. A protective cap of the cap covers each of them and rests on an outer surface of the flange by a bearing face having a sealing O-ring surrounding the plug and housed in a conical bottom groove, allowing the radial expansion of this seal under the effect of a fluid under pressure from the cap and the creation of a leakage of this fluid between the cover and the flange.

BREVE DESCRIPTION DES DESSINSBRIEF DESCRIPTION OF THE DRAWINGS

D'autres caractéristiques et avantages de l'invention ressortiront de la description donnée ci-après à titre d'exemple d'un mode de sa réalisation.Other features and advantages of the invention will emerge from the description given below by way of example of a mode of its realization.

Il sera fait référence aux dessins annexés parmi lesquels :

  • la figure 1 est une vue en coupe axiale de la tête de pompage d'une pompe à membrane selon l'invention,
  • la figure 2 est une vue en coupe axiale d'un détail de la tête de la figure 1 et
  • la figure 3 illustre un autre détail de cette tête.
Reference will be made to the appended drawings among which:
  • the figure 1 is an axial sectional view of the pumping head of a diaphragm pump according to the invention,
  • the figure 2 is an axial sectional view of a detail of the head of the figure 1 and
  • the figure 3 illustrates another detail of this head.

DESCRIPTION DETAILLEE DE L'INVENTIONDETAILED DESCRIPTION OF THE INVENTION

La tête de pompe représentée à la figure 1 comprend, de manière connue, une couronne cylindrique 1 sur le flanc gauche de laquelle est rapporté un flasque 2, en forme de disque plein, au moyen de vis périphériques non représentée tandis que son flanc droit est rapporté sur un bâti 3 de pompe qui en ferme et supporte tous les organes moteurs de celle-ci. Une membrane déformable 4 est pincée entre la couronne et le bâti. La chambre de pompage 5 est ainsi délimitée par la couronne 1, le flasque 2 et la membrane 4. Une boîte à clapets 6 constitue le moyen de raccordement de la chambre de pompage 5 à une canalisation d'aspiration non représentée, au travers d'au moins un clapet unidirectionnel passant de le sens A. Le refoulement de la pompe comprend également une boîte à clapets 7 avec un clapet unidirectionnel dont on voit la queue 8, passant également dans le sens A. La membrane 4 est animée d'une course d'aspiration dans le sens B et d'une course de refoulement dans le sens C au moyen d'un fluide hydraulique contenu dans une chambre de travail 9 qui comporte également un dispositif 10 classique de compensations des fuites.The pump head shown in figure 1 comprises, in known manner, a cylindrical ring 1 on the left flank of which is reported a flange 2, in the form of solid disc, by means of peripheral screws not shown while its right side is attached to a pump frame 3 which in closes and supports all the motor organs of this one. A deformable membrane 4 is clamped between the crown and the frame. The pumping chamber 5 is thus delimited by the ring 1, the flange 2 and the membrane 4. A valve box 6 constitutes the connection means of the pumping chamber 5 to a suction pipe, not shown, through at least one unidirectional valve passing from the direction A. The discharge of the pump also comprises a valve box 7 with a unidirectional valve whose tail 8 is seen, also passing in the direction A. The membrane 4 is driven by a race suction in the direction B and a discharge stroke in the direction C by means of a hydraulic fluid contained in a chamber of Work 9 which also includes a conventional device 10 for compensating leaks.

On comprend au vu de ce dessin que le flasque 3 constitue la pièce qui offre la plus grande surface de contact avec le fluide pompé. Afin de supprimer le contact direct du flasque 3 avec le fluide, on dispose un revêtement 20 sur la surface du flasque tournée vers la chambre de pompage 5. Ce revêtement sera de préférence une feuille de polytétrafluorure d'éthylène (PTFE) d'une épaisseur comprise entre 1 et 5 mm. Pour des pompes de diamètre de l'ordre de 400mm par exemple, l'épaisseur retenue sera de 4 mm. Le PTFE est un matériau rigide de sorte que qu'une épaisseur significative lui confère une indéformabilité qui est intéressante pour obtenir un bon comportement de la pompe dans le temps.It is understood from this drawing that the flange 3 is the part that offers the largest contact area with the pumped fluid. In order to eliminate the direct contact of the flange 3 with the fluid, a coating 20 is placed on the surface of the flange facing the pumping chamber 5. This coating will preferably be a sheet of polyethylene tetrafluoride (PTFE) of a thickness between 1 and 5 mm. For pumps with a diameter of about 400 mm, for example, the thickness retained will be 4 mm. PTFE is a rigid material so that a significant thickness gives it a deformability which is interesting to obtain a good behavior of the pump over time.

Dans le cas de la figure, la feuille 20, obtenue par compression-moulage, est en forme de calotte sphérique pour épouser la surface 21 du flasque 2 de même forme. La feuille 20 est pincée entre la couronne 1 et la flasque 2 par une zone périphérique Z de sorte que son contact dans cette zone avec la surface 21 est un contact étanche (de même d'ailleurs qu'avec la couronne 1). La forme en calotte de la feuille constitue en facteur géométrique supplémentaire de sa résistance à la déformation engendrée par les variations de pression dans la chambre 5.In the case of the figure, the sheet 20, obtained by compression-molding, is shaped spherical cap to fit the surface 21 of the flange 2 of the same shape. The sheet 20 is pinched between the ring 1 and the flange 2 by a peripheral zone Z so that its contact in this area with the surface 21 is a sealed contact (like with the crown 1). The cap-like shape of the sheet constitutes an additional geometrical factor of its resistance to the deformation generated by the pressure variations in the chamber 5.

Le flasque 2 est percé de deux orifices 22 et 23 qui débouchent dans la chambre 5, pour l'un 22, en partie inférieure de la chambre à la limite de la zone Z et pour l'autre, en partie supérieure de la chambre, également à la limite de la zone Z. Il est ainsi possible d'introduire entre la feuille 20 et le flasque 2 un film de liquide incompressible, par exemple d'huile à partir de l'orifice inférieur 22. On force au moyen d'une pompe le liquide dans cet espace de manière à en provoquer l'invasion progressive jusqu'à ce qu'il ressorte par l'orifice supérieur 23. On est ainsi certain d'avoir chassé la totalité de l'air interstitiel qui demeurait entre la feuille et le flasque. On procède ensuite au bouchage de ces orifices. La pompe est alors en état de fonctionner sans perte de cylindrée et sans sollicitation mécanique et de fatigue pour la feuille 20.The flange 2 is pierced with two orifices 22 and 23 which open into the chamber 5, for the one 22, in the lower part of the chamber at the boundary of the zone Z and for the other, in the upper part of the chamber, also at the edge of the zone Z. It is thus possible to introduce between the sheet 20 and the flange 2 a film of incompressible liquid, for example oil from the lower orifice 22. The liquid is forced by means of a pump into this space so as to cause progressive invasion until it comes out of the The upper orifice 23. It is thus certain to have driven out all the interstitial air that remained between the sheet and the flange. These openings are then plugged. The pump is then able to operate without loss of displacement and without mechanical stress and fatigue for the sheet 20.

Aux figures 2 et 3, on a illustré le détail de la pompe au niveau des orifices 22 et 23. On retrouve sur ces figures les éléments déjà décrits avec les mêmes références.To the Figures 2 and 3 , the detail of the pump is illustrated at the openings 22 and 23. In these figures, the elements already described with the same references are found.

L'orifice inférieur 22 est apte à recevoir un bouchon fileté pourvu d'un joint torique d'étanchéité 31 et d'un canal central 32 qui débouche par un canal transversal 32a dans une section 22a de l'orifice 22. Cette section communique avec la section finale 22b de cet orifice 22 au travers d'un siège (rétrécissement) 22c qui peut être obturé par l'extrémité conique 30a du bouchon fileté 30. L'extrémité libre de ce bouchon possède un six pans de manoeuvre 30b surmonté d'un embout de connexion à queue de sapin 30c pour le raccordement temporaire de l'orifice 22 à une source de fluide pressurisé non représentée.The lower orifice 22 is adapted to receive a threaded plug provided with an O-ring seal 31 and a central channel 32 which opens through a transverse channel 32a in a section 22a of the orifice 22. This section communicates with the final section 22b of this orifice 22 through a seat (shrink) 22c which can be closed by the conical end 30a of the threaded cap 30. The free end of this plug has a six maneuvering faces 30b surmounted by a fir-tail connecting end 30c for the temporary connection of the orifice 22 to a source of pressurized fluid not shown.

On comprend que lorsque l'espace entre le flasque et la feuille est totalement rempli, il suffit à l'opérateur de visser le bouchon à fond pour faire porter l'extrémité conique 30a de ce dernier contre le siège 22c, extrémité qui en avait été auparavant maintenue éloignée par un vissage partiel du bouchon dans l'orifice afin de permettre le passage du fluide de gavage.It is understood that when the space between the flange and the sheet is completely filled, it is sufficient for the operator to screw the cap fully to bear the tapered end 30a of the latter against the seat 22c, which end had been previously kept away by a partial screwing of the plug in the orifice to allow the passage of the force-feeding fluid.

Pour ce qui concerne l'orifice 23, un autre bouchon fileté 35 est mis en place. Dans une version basique non représentée, ce bouchon est une simple vis pointeau (avec canaux central et transversal comme pour le bouchon 30) qui vient boucher le rétrécissement 23c de cet orifice. Dans la version représenté, le bouchon 35 comporte une extrémité 35a en forme de cône de centrage pour une bille 36 qui peut ainsi être plaquée contre le siège 23c par le bouchon ou qui peut, avec un vissage partiel, être libre entre ce siège et le cône de centrage. L'intérêt de cette structure est qu'une fois le gavage achevé, on ferme le bouchon de l'alimentation et on actionne la pompe sur quelques cycles d'aspiration/refoulement pour totalement dégazer l'espace entre le flasque et la feuille. La bille joue alors le rôle d'un clapet anti-retour qui permet au fluide ou gaz d'échapper à chaque course de refoulement tout en fermant le canal 23 pendant chaque course d'aspiration. Ces quelques cycles accomplis, on serre le bouchon 35 qui obture totalement l'orifice 23.As regards the orifice 23, another threaded plug 35 is put in place. In a basic version not shown, this plug is a simple needle screw (with central and transverse channels as for the plug 30) which closes the shrinkage 23c of this orifice. In the version shown, the cap 35 has a cone-shaped end 35a for a ball 36 which can thus be pressed against the seat 23c by the plug or which can, with a partial screwing, be free between this seat and the seat. centering cone. The advantage of this structure is that once the feeding is complete, it closes the cap of the supply and the pump is actuated on a few cycles of suction / discharge to completely degas the space between the flange and the sheet. The ball then acts as a non-return valve which allows the fluid or gas to escape each discharge stroke while closing the channel 23 during each suction stroke. These few completed cycles, we tighten the cap 35 which completely closes the orifice 23.

Il faut noter enfin sur chacune de ces figures, la présence d'un capot 40 qui vient recouvrir l'embout 30c, 35c de chaque bouchon pour le protéger des coups et salissures extérieures. La particularité de ce capot réside dans le fait qu'il est serré contre la face extérieure du flasque 2 de manière étanche grâce à un joint torique 41 qui est logé dans une gorge (ou lamage) 42 à fond 43 conique. Au moment du montage du capot, le joint est légèrement comprimé entre le flasque 2 et le fond 43 de la gorge. Si une fuite se produit au niveau du bouchon capoté, le fluide accumulé dans le bouchon tend sous la pression croissante à chaque coup de pompe, d e repousser vers l'extérieur le joint 41. Celui-ci est prévu pour se dilater et donc occuper un endroit de la gorge où sa compression disparaît du fait de la conicité du fond 43 de la gorge. Une fuite du liquide est alors possible, ce qui est un signe d'alarme pour l'opérateur et surtout qui empêche au fluide sous pression de faire sauter le capot et ainsi faire disparaître la protection des embouts de bouchon.Finally, it should be noted in each of these figures, the presence of a cap 40 which covers the tip 30c, 35c of each cap to protect it from blows and external dirt. The peculiarity of this hood lies in the fact that it is clamped against the outer face of the flange 2 sealingly through an O-ring 41 which is housed in a groove (or countersink) 42 to bottom 43 conical. At the time of mounting the cover, the seal is slightly compressed between the flange 2 and the bottom 43 of the groove. If a leak occurs at the covered cap, the fluid accumulated in the plug tends under increasing pressure with each stroke of the pump, to push outward the seal 41. It is intended to expand and thus occupy a place in the throat where its compression disappears due to the taper of the bottom 43 of the throat. A leak of the liquid is then possible, which is a sign of alarm for the operator and especially that prevents pressurized fluid to blow the hood and thus remove the protection of the cap ends.

Aux figures 2 et 3, on a enfin représenté une variante de réalisation de la protection du flasque dans laquelle la feuille 20a est plane mais recouverte d'une tôle métallique 20b qui lui confère la capacité à résister sans déformation aux variations de pression dans la chambre 5. Cette tôle est également pincée en périphérie entre la couronne 1 et le flasque 2 de la tête de pompe.To the Figures 2 and 3 Finally, an alternative embodiment of the protection of the flange in which the sheet 20a is flat but covered with a metal sheet 20b which gives it the capacity to resist without deformation to the pressure variations in the chamber 5 is shown. also pinched at the periphery between the ring 1 and the flange 2 of the pump head.

Claims (5)

  1. A pump, in particular for a chemically reactive fluid, in which a pump head comprises at least two walls (2, 4) between which there is defined a pump chamber (5) for pumping the fluid in question, one of the walls (2) being stationary, the other wall (4) being movable or deformable relative to the stationary wall (2) by means of a drive or deformation device (9), at least the stationary wall (2) being provided with a protective coating (20) against the fluid, constituted by a sheet (20) of plastics material applied in leaktight manner against the stationary wall (2) at the periphery (Z) thereof, characterized in that the space between the protected surface (21) and the coating sheet (20), within the zone (Z) where they make leaktight contact, is filled with an incompressible liquid.
  2. A pump according to claim 1, characterized in that the sheet (20) is in the shape of a substantially spherical or conical cap complementary to the inside surface (21) of the side plate (2) so as to fit against it as closely as possible, with the convex side of this shape facing towards the inside of the chamber (5).
  3. A pump according to claim 1, characterized in that it has a protective plate (20b) for protecting the surface of the sheet (20a) that faces towards the pump chamber.
  4. A pump according to any preceding claim, characterized in that it includes means for filling the space between the side plate (2) and the sheet (20, 20a) with fluid, which means are constituted by two orifices (22, 23), formed in the side plate (2) and opening out in the immediate proximity of the leaktight zone (Z) between the sheet (20, 20a) and the pump head, one of the orifices (22) being in the lowest portion and the other orifice (23) being in the highest portion of the pump chamber (5), and each orifice having a threaded plug (30, 35) for closing it.
  5. A pump according to any preceding claim, characterized in that each of the plugs (30, 35) is protected by a respective cap (40) resting against an outside surface of the side plate (2) via a bearing face that includes an O-ring (41) surrounding the plug (30, 35) and received in a groove (42) having a conical bottom (43) that enables the O-ring (41) to expand radially under the effect of fluid under pressure coming from the plug, thereby creating a leak of said fluid between the cap (40) and the side plate (2).
EP08290218A 2007-03-13 2008-03-06 Dispensing pump with an isolating membrane of one of its walls or end flange of the dispensing chamber Expired - Fee Related EP1972783B1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR0701786A FR2913732B1 (en) 2007-03-13 2007-03-13 MEMBRANE-ASSISTED DOSING PUMP OF ONE OF ITS WALLS OR EXTENT FLAG OF THE DOSING CHAMBER

Publications (2)

Publication Number Publication Date
EP1972783A1 EP1972783A1 (en) 2008-09-24
EP1972783B1 true EP1972783B1 (en) 2010-05-12

Family

ID=38581918

Family Applications (1)

Application Number Title Priority Date Filing Date
EP08290218A Expired - Fee Related EP1972783B1 (en) 2007-03-13 2008-03-06 Dispensing pump with an isolating membrane of one of its walls or end flange of the dispensing chamber

Country Status (5)

Country Link
US (1) US7836814B2 (en)
EP (1) EP1972783B1 (en)
DE (1) DE602008001184D1 (en)
ES (1) ES2344489T3 (en)
FR (1) FR2913732B1 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112309150B (en) * 2020-12-07 2021-12-28 吉安市永安交通设施有限公司 Movable traffic signal lamp

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2496711A (en) * 1946-11-02 1950-02-07 Daniel And Florence Guggenheim Pumping apparatus for very cold liquids
US2753804A (en) * 1951-09-26 1956-07-10 Int Paper Box Machine Co Diaphragm pump
US3000320A (en) * 1957-07-18 1961-09-19 Ring Sandiford Pump
US3212448A (en) * 1963-04-22 1965-10-19 Clevite Corp Fluid apparatus
US3781141A (en) * 1971-07-12 1973-12-25 Dorr Oliver Inc Air pressure actuated single-acting diaphragm pump
GB1433758A (en) * 1973-10-23 1976-04-28 Hamilton T W Membrane pump
DE8525733U1 (en) * 1985-09-10 1987-01-15 Becker, Erich, 7812 Bad Krozingen Diaphragm pump
DE10012902B4 (en) * 2000-03-16 2004-02-05 Lewa Herbert Ott Gmbh + Co. Breathable membrane clamping

Also Published As

Publication number Publication date
DE602008001184D1 (en) 2010-06-24
FR2913732A1 (en) 2008-09-19
FR2913732B1 (en) 2012-08-17
EP1972783A1 (en) 2008-09-24
US7836814B2 (en) 2010-11-23
ES2344489T3 (en) 2010-08-27
US20080226478A1 (en) 2008-09-18

Similar Documents

Publication Publication Date Title
EP3025060B1 (en) Sealing device for piston
FR2557246A1 (en) SHUT-OFF DEVICE FOR VALVE-VALVE
EP3686427B1 (en) Pump for a liquid product comprising a sealing device and spraying system comprising such a pump
EP1974160A1 (en) Gas injection valve with two positions of closure
EP1748232B1 (en) Seal for a sparkplug well
EP1972783B1 (en) Dispensing pump with an isolating membrane of one of its walls or end flange of the dispensing chamber
FR2732742A1 (en) INTAKE VALVE ASSEMBLY.
EP1618324B1 (en) Fluid flow control valve device
FR2645237A1 (en) Retention valve for diaphragm pump
EP0777065A1 (en) Sphere, especially a pneumatic sphere, for example for the hydropneumatic suspension of a motorvehicle
EP0159236B1 (en) Hydraulic-pressure generator and its annular seal
FR2594520A1 (en) ROD END SEAL FOR STOP VALVE
CH713979A2 (en) Security valve for watch.
WO2007085539A1 (en) Adjustable pressure reducer with low pressure double bellows
EP2619493B1 (en) Pressure relief valve, in particular for domestic water distribution equipment
FR2480896A1 (en) VALVE WITH CONICAL SEAT
FR2934332A1 (en) Fluid metering pump, has membrane mounted between cylindrical body and pump head, and comprising cylindrical peripheral rim for directly locking membrane between body and head, where concavity of membrane is turned towards pumping chamber
EP2444668A1 (en) Membrane pump with high suction capacity
EP1215425B1 (en) Sealing system for a valve
EP2484422B1 (en) Filter
FR2607898A1 (en) A-COUPE SUPPRESSOR IN A FLUID CIRCUIT
FR2764344A1 (en) Membrane pump with leak detection
CH443921A (en) Diaphragm pump
FR3133812A1 (en) Hydraulic pressure generator module for a braking system
FR2507733A1 (en) VALVE WITH DIRECT PASSAGE

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT RO SE SI SK TR

AX Request for extension of the european patent

Extension state: AL BA MK RS

17P Request for examination filed

Effective date: 20090310

AKX Designation fees paid

Designated state(s): DE ES FR GB IT

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE ES FR GB IT

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

Free format text: NOT ENGLISH

REF Corresponds to:

Ref document number: 602008001184

Country of ref document: DE

Date of ref document: 20100624

Kind code of ref document: P

REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2344489

Country of ref document: ES

Kind code of ref document: T3

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20110215

REG Reference to a national code

Ref country code: DE

Ref legal event code: R097

Ref document number: 602008001184

Country of ref document: DE

Effective date: 20110214

REG Reference to a national code

Ref country code: DE

Ref legal event code: R082

Ref document number: 602008001184

Country of ref document: DE

Representative=s name: SCHAUMBURG & PARTNER PATENTANWAELTE GBR, DE

Ref country code: DE

Ref legal event code: R082

Ref document number: 602008001184

Country of ref document: DE

Representative=s name: SCHAUMBURG & PARTNER PATENTANWAELTE MBB, DE

Ref country code: DE

Ref legal event code: R082

Ref document number: 602008001184

Country of ref document: DE

Representative=s name: SCHAUMBURG UND PARTNER PATENTANWAELTE MBB, DE

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 9

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20170228

Year of fee payment: 10

Ref country code: DE

Payment date: 20170228

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20170222

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: ES

Payment date: 20170228

Year of fee payment: 10

Ref country code: IT

Payment date: 20170324

Year of fee payment: 10

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 602008001184

Country of ref document: DE

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20180306

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20181002

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20180306

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20180306

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20180331

REG Reference to a national code

Ref country code: ES

Ref legal event code: FD2A

Effective date: 20190904

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20180307