EP0032469B1 - Pipette with positive displacement - Google Patents

Pipette with positive displacement Download PDF

Info

Publication number
EP0032469B1
EP0032469B1 EP81400023A EP81400023A EP0032469B1 EP 0032469 B1 EP0032469 B1 EP 0032469B1 EP 81400023 A EP81400023 A EP 81400023A EP 81400023 A EP81400023 A EP 81400023A EP 0032469 B1 EP0032469 B1 EP 0032469B1
Authority
EP
European Patent Office
Prior art keywords
pipette
piston
tip
pincer
control rod
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
EP81400023A
Other languages
German (de)
French (fr)
Other versions
EP0032469A1 (en
Inventor
Eric Marteau D'autry
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.)
Individual
Original Assignee
Individual
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 Individual filed Critical Individual
Priority to AT81400023T priority Critical patent/ATE3248T1/en
Publication of EP0032469A1 publication Critical patent/EP0032469A1/en
Application granted granted Critical
Publication of EP0032469B1 publication Critical patent/EP0032469B1/en
Expired legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L3/00—Containers or dishes for laboratory use, e.g. laboratory glassware; Droppers
    • B01L3/02—Burettes; Pipettes
    • B01L3/021—Pipettes, i.e. with only one conduit for withdrawing and redistributing liquids
    • B01L3/0217—Pipettes, i.e. with only one conduit for withdrawing and redistributing liquids of the plunger pump type
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01L—CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE
    • B01L3/00—Containers or dishes for laboratory use, e.g. laboratory glassware; Droppers
    • B01L3/02—Burettes; Pipettes
    • B01L3/0275—Interchangeable or disposable dispensing tips
    • B01L3/0279—Interchangeable or disposable dispensing tips co-operating with positive ejection means

Definitions

  • the present invention relates to an improvement made to precision positive displacement pipettes intended for the sampling and distribution of small quantities of liquid.
  • such positive displacement precision pipettes are already known which are of the type comprising an essentially tubular pipette body at the lower end of which is arranged a calibrated capillary tube in which it moves in a sealed and against an upward elastic restoring force exerted by a main spring, a piston controlled in its downward movement by a control rod protruding from the upper end of said pipette body, as well as a clamping member of the upper end of the piston, which is of the type with elastic branches deviating radially by displacement against the force exerted by a second spring of resistance much greater than that of the main spring and which is integral in translation with said rod control.
  • Such a positive displacement pipette is for example described in French patent application FR-A-2 446 672 belonging to the applicant.
  • the present improvement made to such a type of positive displacement pipette lies mainly in its particular arrangement intended to allow simultaneous ejection of the capillary tip and of the piston, without the operator having to directly manipulate the capillary and / or the piston. It is clear that, when handling radioactive samples or any other contaminated liquid samples, it is crucial to be able to easily ensure such simultaneous ejection of the capillary tip and of the piston which constitute the only contaminated pipette organs by the liquid withdrawn.
  • the precision pipette with positive displacement is characterized in that it comprises a tip with a calibrated capillary orifice, capable of cooperating by fitting with the free lower end of the pipette body, the orifice of the latter. end allowing the passage of at least a part of the pinching member which, in the vicinity of the end of its downward stroke, comes into contact with a stop formed on the inner surface of the endpiece to ensure the simultaneous ejection of said tip and of the piston which remains trapped in the capillary orifice.
  • the positive displacement pipette comprises an essentially tubular body 10 which, in the particular embodiment described, consists of two separate parts which are secured to each other by screwing.
  • the upper part or housing 12 incorporates for example a mechanism for adjusting and displaying the volume to be withdrawn and distributed, and the lower tubular part 14 is used mainly for guiding the nipping member 16 of the piston 18.
  • the particular mechanism of adjustment and display illustrated in Figures 1 and 2 is not part of the present invention and will therefore not be described here in detail.
  • a calibrated capillary 20 in which moves, in a sealed manner and against an upward elastic restoring force exerted by a main spring 22, a piston 18 controlled in its movement by a control rod 24 projecting from the upper end of the housing 12 of the pipette body 10.
  • the pipette has a tip 26 which has a calibrated through capillary orifice 20 and which is able to cooperate by fitting with the free lower end of the pipette body 10.
  • a tip 26 will be produced in a thermoplastic material chosen to resist the samples with which it comes into contact.
  • the piston 18 has at least one sealing zone 28 coming into intimate contact with the inner surface of the capillary 20.
  • Such a piston 18 can for example advantageously be produced in the form of a stainless steel wire having a coating, for example a Teflon coating, at the level of the sealing zone 28. As shown in FIGS. 1 and 4, such a coating can for example have a general cylindrical shape or else can be equipped at its periphery with at least one annular sealing lip coming into intimate contact with the interior surface of the capillary tube 20.
  • Such a type of pipette also comprises a clamping member 16 of the upper end of the piston 18, which is of the type with elastic branches deviating radially by displacement against the force exerted by a second spring 30 of very high resistance. greater than that of the main spring 22. It is clear that such a clamping member 16 must be secured in translation with the control rod 24 of the pipette.
  • the clamping member 16 is in the form of a self-contained cartridge comprising a clamp proper 32 ending at its lower end by elastic branches 34 and the other end of which 36 is screwed into a clamp support 38.
  • This clamp support 38 is capable of sliding, against the force exerted by the second spring 30 and according to a partial stroke in the upper part of the orifice 40 of the door clamp 42.
  • This latter clamp holder 42 slides itself inside the lower part 14 of the pipette body 10 against the force exerted by the main spring 22.
  • the end of the elastic branches 34 has an outwardly flaring surface capable of being applied tightly against the conical lower opening 44 of the clamp holder 42 and this precisely under the action of the force exerted by the second spring 30.
  • the mounting of the cartridge pr said operation is carried out as follows.
  • the clamp 32 is introduced through the conical lower opening 44 of the clamp holder 42, until the flared lower end of the elastic branches 34 come to bear tightly against the conical lower opening 44 of the clamp holder 42.
  • the second spring 30 is then introduced into the clamp holder 42 by its upper end and around the clamp itself 32, then the clamp holder 38 is screwed onto the upper end 36 of the clamp 32, thereby compressing the second spring 30.
  • the main spring 22 comes to bear fixedly on a shoulder 48 formed on the inner surface of the lower part 14 of the pipette body 10, in the vicinity of its free lower end.
  • the clamp holder 42 comes into upper abutment at its upper free surface 50 against an adjustment screw 52 whose variable vertical position makes it possible to adjust the useful stroke of sampling and dispensing the liquid sample.
  • the cooperation of the control rod 24 and the clamping member 16 takes place at the upper surface of the clamp support 38 which is advantageously in the form of a spherical recess 54 able to cooperate with a lower end in the shape of a ball joint 56 of the control rod 24.
  • a small mounting clearance will be maintained between the ball joint 56 of the control rod 24 and the upper surface of the spherical recess 54 of the clamp holder 42, so as to ensure that the frank limit stop up stroke is made at the contact between the clamp holder 42 and the adjusting screw 52 and not through the control rod 24 itself.
  • the separation of the clamp holder 16 and the rest of the control rod 24 makes it possible, in particular by making use of a ball-and-socket contact between these two elements, to avoid any problem of alignment perfect of the different components of the mobile pipette assembly.
  • an adjustable pipette ie the upper stop of limitation of sampling stroke is adjustable by the operator by acting on the adjustable screw in vertical position 52.
  • the present invention is however not not limited to such a type of adjustable pipette, but may also extend to fixed pipettes, ie to pipettes whose adjusting screw would be replaced by an upstroke limit stop which remains fixed in position relative to the pipette body 10.
  • the stop limiting the downward direction of the useful dispensing stroke of the pipette is carried out at a shoulder 58 formed in the vicinity of the lower part of the clamp holder 42.
  • This shoulder 58 is able to cooperate with the shoulder corresponding 48 formed in the vicinity of the lower end of the pipette body 10.
  • Such a lower limit position of the clamp holder 16 is illustrated in thin dashed lines in FIG. 4. It will be noted that this position is obtained by compression complete with main spring 22.
  • the orifice 60 of the free lower end of the pipette body 10 is arranged so as to allow the passage of at least part of the clamping member 16 which, at the end of the downward stroke, comes into contact with a stop 62 formed on the internal surface of the end piece 26.
  • the ends of the elastic branches 34 of the clamp 32 freely project from the conical lower end 44 of the clamp holder 42.
  • the ejection of the tip 26 of the pipette is therefore obtained by exerting a additional force on the control rod 24, which makes it possible to compress the second spring 30.
  • the compression of this second spring 30 causes, beyond the position illustrated in FIG. 4 ie when the clamp holder 42 is in lower stop, in a first step the spacing of the elastic branches 34 which allows the release of the piston 18.
  • the support of the free ends of the elastic branches 34, in the separated state, on the stop 62 formed on the inner surface of the nozzle 26 then performs the actual ejection of the nozzle 26 in the capillary orifice 20 of which the piston 18 remains trapped.
  • the stop 62 formed on the interior surface of the endpiece 26 is in the form of a surface in inward recess.
  • said piston and its sealing zone 28 are arranged such that at the end of the complete travel of the control rod 24, the piston 18 does not escape from the capillary orifice 20 through the free lower end of the latter.
  • the inner surface of the upper part of the endpiece 26 has at least one annular zone 64 projecting or recessed capable of cooperating elastically with an annular zone 66 corresponding recessed or protruding formed on the outer lateral surface of the lower part 14 of the pipette body 10.
  • These annular zones 64, 66 projecting or recessed have been arranged so as to allow a large guide range of the nozzle. 26 on the end of the pipette, for example of the order of 5 to 10 mm and preferably from 6 to 8 mm.
  • these annular zones 64, 66 projecting or recessed are also arranged so as to ensure a short stroke of engagement and disengagement of the endpiece 26, of the order of 2 mm.
  • the compression of the second spring 30 firstly results in a free travel of the order of 5 tenths of a millimeter during which the elastic branches 34 of the clamp 32 move apart. and release the piston 18. Then, when one continues to compress the second spring 30, one obtains a second stroke of the order of the order of 2.5 mm which ensures precisely, by contacting the ends of the branches spaced apart 34 from the clamp 32 with the abutment surface 62 inside the endpiece 26, exceeding this disengagement stroke of the endpiece which is of the order of 2 mm.

Abstract

High-precision positive-displacement pipette having a nozzle with calibrated capillary channel and capable of disengageably fitting together with the free lower end of the pipette body. A piston fits tightly in the capillary channel and is controlled by a manually operable control rod equipped with a gripping device with which it grips the piston. An opening at this end of the body permits at least a part of the gripping device to pass through and come into contact with a stop provided on the inner surface of the nozzle so as to ensure the simultaneous ejection of the nozzle and of the piston which remains captive in the capillary channel.

Description

La présente invention concerne un perfectionnement apporté aux pipettes de précision à déplacement positif destinées au prélèvement et à la distribution de petites quantités de liquide.The present invention relates to an improvement made to precision positive displacement pipettes intended for the sampling and distribution of small quantities of liquid.

Dans la technique antérieure on connaît déjà de telles pipettes de précision à déplacement positif qui sont du type comprenant un corps de pipette essentiellement tubulaire à l'extrémité inférieure duquel est agencé un tube capillaire calibré dans lequel se déplace, de façon étanche et à l'encontre d'une force de rappel élastique vers le haut exercée par un ressort principal, un piston commandé dans son déplacement vers le bas par une tige de commande dépassant de l'extrémité supérieure dudit corps de pipette, ainsi qu'un organe de pincement de l'extrémité supérieure du piston, qui est du type à branches élastiques s'écartant radialement par déplacement à l'encontre de la force exercée par un second ressort de résistance très supérieure à celle du ressort principal et qui est solidaire en translation avec ladite tige de commande. Une telle pipette à déplacement positif est par exemple décrite dans la demande de brevet français FR-A-2 446 672 appartenant à la demanderesse.In the prior art, such positive displacement precision pipettes are already known which are of the type comprising an essentially tubular pipette body at the lower end of which is arranged a calibrated capillary tube in which it moves in a sealed and against an upward elastic restoring force exerted by a main spring, a piston controlled in its downward movement by a control rod protruding from the upper end of said pipette body, as well as a clamping member of the upper end of the piston, which is of the type with elastic branches deviating radially by displacement against the force exerted by a second spring of resistance much greater than that of the main spring and which is integral in translation with said rod control. Such a positive displacement pipette is for example described in French patent application FR-A-2 446 672 belonging to the applicant.

Le présent perfectionnement apporté à un tel type de pipette à déplacement positif réside principalement dans son agencement particulier destiné à permettre une éjection simultanée de l'embout capillaire et du piston, sans que l'opérateur n'ait à manipuler directement le capillaire et/ou le piston. Il est clair que, lors de la manipulation d'échantillons radioactifs ou encore de tous autres échantillons liquides contaminés, il est déterminant de pouvoir assurer facilement une telle éjection simultanée de l'embout capillaire et du piston qui constituent les seuls organes de la pipette contaminés par le liquide prélevé.The present improvement made to such a type of positive displacement pipette lies mainly in its particular arrangement intended to allow simultaneous ejection of the capillary tip and of the piston, without the operator having to directly manipulate the capillary and / or the piston. It is clear that, when handling radioactive samples or any other contaminated liquid samples, it is crucial to be able to easily ensure such simultaneous ejection of the capillary tip and of the piston which constitute the only contaminated pipette organs by the liquid withdrawn.

Conformément à la présente invention, la pipette de précision à déplacement positif est caractérisée en ce qu'elle comporte un embout à orifice capillaire calibré, apte à coopérer par emmanchement avec l'extrémité inférieure libre du corps de pipette, l'orifice de cette dernière extrémité permettant le passage d'au moins une partie de l'organe de pincement qui, au voisinage de la fin de sa course vers le bas, vient au contact d'une butée ménagée sur la surface intérieure de l'embout pour assurer l'éjection simultanée dudit embout et du piston qui reste prisonnier dans l'orifice capillaire.According to the present invention, the precision pipette with positive displacement is characterized in that it comprises a tip with a calibrated capillary orifice, capable of cooperating by fitting with the free lower end of the pipette body, the orifice of the latter. end allowing the passage of at least a part of the pinching member which, in the vicinity of the end of its downward stroke, comes into contact with a stop formed on the inner surface of the endpiece to ensure the simultaneous ejection of said tip and of the piston which remains trapped in the capillary orifice.

Un certain nombre d'autres caractéristiques et avantages de la pipette à déplacement positif selon l'invention apparaîtront à la lecture de la description détaillée faite ci-après en référence aux dessins annexés sur lesquels :

  • la figure 1 représente une vue en coupe de l'ensemble d'une pipette à déplacement positif selon l'invention ;
  • la figure 2 représente une vue à plus grande échelle de la partie supérieure de la pipette illustrée à la figure 1 ;
  • la figure 3 représente une vue à plus grande échelle de l'organe de pincement réalisé sous la forme d'une cartouche autonome, et
  • la figure 4 représente une vue à plus grande échelle de la partie inférieure de la pipette, sur laquelle apparaît en traits mixtes fins la pince- cartouche de la figure 3 dans sa position limite inférieure correspondant à la fin de course d'éjection.
A certain number of other characteristics and advantages of the positive displacement pipette according to the invention will appear on reading the detailed description given below with reference to the appended drawings in which:
  • Figure 1 shows a sectional view of the assembly of a positive displacement pipette according to the invention;
  • FIG. 2 represents an enlarged view of the upper part of the pipette illustrated in FIG. 1;
  • FIG. 3 represents a view on a larger scale of the clamping member produced in the form of an autonomous cartridge, and
  • 4 shows a view on a larger scale of the lower part of the pipette, on which appears in thin broken lines the cartridge clamp of Figure 3 in its lower limit position corresponding to the end of ejection stroke.

La pipette à déplacement positif selon l'invention comporte un corps essentiellement tubulaire 10 qui, dans le mode de réalisation particulier décrit, est constitué en deux parties distinctes solidarisées entre-elles par vissage. La partie supérieure ou boîtier 12 incorpore par exemple un mécanisme de réglage et d'affichage du volume à prélever et à distribuer, et la partie inférieure tubulaire 14 sert principalement au guidage de l'organe de pincement 16 du piston 18. Le mécanisme particulier de réglage et d'affichage illustré aux figures 1 et 2 ne fait pas partie de la présente invention et ne sera donc pas décrit ici en détail.The positive displacement pipette according to the invention comprises an essentially tubular body 10 which, in the particular embodiment described, consists of two separate parts which are secured to each other by screwing. The upper part or housing 12 incorporates for example a mechanism for adjusting and displaying the volume to be withdrawn and distributed, and the lower tubular part 14 is used mainly for guiding the nipping member 16 of the piston 18. The particular mechanism of adjustment and display illustrated in Figures 1 and 2 is not part of the present invention and will therefore not be described here in detail.

De façon classique, à l'extrémité inférieure de la partie 14 du corps de pipette 10 se trouve agencé un capillaire calibré 20 dans lequel se déplace, de façon étanche et à l'encontre d'une force de rappel élastique vers le haut exercée par un ressort principal 22, un piston 18 commandé dans son déplacement par une tige de commande 24 dépassant de l'extrémité supérieure du boîtier 12 du corps de pipette 10.Conventionally, at the lower end of the part 14 of the pipette body 10 is arranged a calibrated capillary 20 in which moves, in a sealed manner and against an upward elastic restoring force exerted by a main spring 22, a piston 18 controlled in its movement by a control rod 24 projecting from the upper end of the housing 12 of the pipette body 10.

Conformément à la présente invention, la pipette comporte un embout 26 qui présente un orifice capillaire calibré traversant 20 et qui est apte à coopérer par emmanchement avec l'extrémité inférieure libre du corps de pipette 10. De façon avantageuse, un tel embout 26 sera réalisé en une matière thermoplastique choisie pour résister aux échantillons avec lesquels il entre en contact. Dans un tel type de pipette, il est indispensable que le piston 18 présente au moins une zone d'étanchéité 28 venant au contact intime de la surface intérieure du capillaire 20. Un tel piston 18 peut par exemple être avantageusement réalisé sous la forme d'un fil d'acier inoxydable présentant un enrobage, par exemple un enrobage en téflon, au niveau de la zone d'étanchéité 28. Comme cela se trouve illustré sur les figures 1 et 4, un tel enrobage peut par exemple affecter une forme générale cylindrique ou encore peut être équipé à sa périphérie d'au moins une lèvre annulaire d'étanchéité venant au contact intime de la surface intérieure du tube capillaire 20.According to the present invention, the pipette has a tip 26 which has a calibrated through capillary orifice 20 and which is able to cooperate by fitting with the free lower end of the pipette body 10. Advantageously, such a tip 26 will be produced in a thermoplastic material chosen to resist the samples with which it comes into contact. In such a type of pipette, it is essential that the piston 18 has at least one sealing zone 28 coming into intimate contact with the inner surface of the capillary 20. Such a piston 18 can for example advantageously be produced in the form of a stainless steel wire having a coating, for example a Teflon coating, at the level of the sealing zone 28. As shown in FIGS. 1 and 4, such a coating can for example have a general cylindrical shape or else can be equipped at its periphery with at least one annular sealing lip coming into intimate contact with the interior surface of the capillary tube 20.

Un tel type de pipette comporte également un organe de pincement 16 de l'extrémité supérieure du piston 18, qui est du type à branches élastiques s'écartant radialement par déplacement à l'encontre de la force exercée par un second ressort 30 de résistance très supérieure à celle du ressort principal 22. Il est clair qu'un tel organe de pincement 16 doit être solidaire en translation avec la tige de commande 24 de la pipette.Such a type of pipette also comprises a clamping member 16 of the upper end of the piston 18, which is of the type with elastic branches deviating radially by displacement against the force exerted by a second spring 30 of very high resistance. greater than that of the main spring 22. It is clear that such a clamping member 16 must be secured in translation with the control rod 24 of the pipette.

Selon un mode de réalisatiôn particulier de la présente invention, l'organe de pincement 16 se présente sous la forme d'une cartouche autonome comprenant une pince proprement dite 32 se terminant à son extrémité inférieure par des branches élastiques 34 et dont l'autre extrémité 36 se trouve vissée dans un support de pince 38. Ce support de pince 38 est apte à coulisser, à l'encontre de la force exercée par le second ressort 30 et selon une course partielle dans la partie supérieure de l'orifice 40 du porte-pince 42. Ce dernier porte-pince 42 coulisse lui-même à l'intérieur de la partie inférieure 14 du corps de pipette 10 à l'encontre de la force exercée par le ressort principal 22. Il est important que l'extrémité des branches élastiques 34 présente une surface s'évasant vers l'extérieur apte à s'appliquer étroitement contre l'ouverture inférieure conique 44 du porte-pince 42 et ceci précisément sous l'action de la force exercée par le second ressort 30. Le montage de la cartouche proprement dite (organe de pincement 16) s'effectue de la manière suivante. On introduit la pince 32 par l'ouverture inférieure conique 44 du porte-pince 42, jusqu'à ce que l'extrémité inférieure évasée des branches élastiques 34 viennent s'appliquer étroitement contre l'ouverture inférieure conique 44 du porte-pince 42. On introduit alors le second ressort 30 dans le porte-pince 42 par son extrémité supérieure et autour de la pince proprement dite 32, puis l'on visse sur l'extrémité supérieure 36 de la pince 32 le support de pince 38 en venant ainsi comprimer le second ressort 30.According to a particular embodiment of the present invention, the clamping member 16 is in the form of a self-contained cartridge comprising a clamp proper 32 ending at its lower end by elastic branches 34 and the other end of which 36 is screwed into a clamp support 38. This clamp support 38 is capable of sliding, against the force exerted by the second spring 30 and according to a partial stroke in the upper part of the orifice 40 of the door clamp 42. This latter clamp holder 42 slides itself inside the lower part 14 of the pipette body 10 against the force exerted by the main spring 22. It is important that the end of the elastic branches 34 has an outwardly flaring surface capable of being applied tightly against the conical lower opening 44 of the clamp holder 42 and this precisely under the action of the force exerted by the second spring 30. The mounting of the cartridge pr said operation (pinching member 16) is carried out as follows. The clamp 32 is introduced through the conical lower opening 44 of the clamp holder 42, until the flared lower end of the elastic branches 34 come to bear tightly against the conical lower opening 44 of the clamp holder 42. The second spring 30 is then introduced into the clamp holder 42 by its upper end and around the clamp itself 32, then the clamp holder 38 is screwed onto the upper end 36 of the clamp 32, thereby compressing the second spring 30.

On constate, par exemple sur la figure 3, que l'ensemble de cette cartouche qui constitue l'organe de pincement 16 du piston 18, est élastiquement sollicité vers le haut sous l'action de la force exercée par le ressort principal 22. A cet effet, le porte-pince présente un épaulement 46 contre lequel vient s'appuyer le ressort principalIt can be seen, for example in FIG. 3, that the assembly of this cartridge which constitutes the clamping member 16 of the piston 18, is elastically urged upwards under the action of the force exerted by the main spring 22. A for this purpose, the clamp holder has a shoulder 46 against which the main spring bears.

22. Par son extrémité inférieure, le ressort principal 22 vient en appui fixe sur un épaulement 48 ménagé sur la surface intérieure de la partie inférieure 14 du corps de pipette 10, au voisinage de son extrémité inférieure libre. Dans le mode de réalisation particulier décrit, le porte-pince 42 vient en butée supérieure au niveau de sa surface libre supérieure 50 à l'encontre d'une vis de réglage 52 dont la position verticale variable permet de régler la course utile de prélèvement et de distribution de l'échantillon liquide. On notera sur la figure 3 que la coopération de la tige de commande 24 et de l'organe de pincement 16 s'effectue au niveau de la surface supérieure du support de pince 38 qui se présente avantageusement sous la forme d'un évidement sphérique 54 apte à coopérer avec une extrémité inférieure en forme de rotule 56 de la tige de commande 24.22. By its lower end, the main spring 22 comes to bear fixedly on a shoulder 48 formed on the inner surface of the lower part 14 of the pipette body 10, in the vicinity of its free lower end. In the particular embodiment described, the clamp holder 42 comes into upper abutment at its upper free surface 50 against an adjustment screw 52 whose variable vertical position makes it possible to adjust the useful stroke of sampling and dispensing the liquid sample. Note in Figure 3 that the cooperation of the control rod 24 and the clamping member 16 takes place at the upper surface of the clamp support 38 which is advantageously in the form of a spherical recess 54 able to cooperate with a lower end in the shape of a ball joint 56 of the control rod 24.

De façon avantageuse, on maintiendra un faible jeu de montage entre la rotule 56 de la tige de commande 24 et la surface supérieure de l'évidement sphérique 54 du porte-pince 42, de manière à bien s'assurer que la butée franche de limitation de course vers le haut soit réalisée au niveau du contact entre le porte-pince 42 et la vis de réglage 52 et non par l'intermédiaire de la tige de commande 24 proprement dite. Il convient ici de noter que la désolidarisation de l'organe porte-pince 16 et du reste de la tige de commande 24 permet, en particulier en faisant appel à un contact à rotule entre ces deux éléments, d'éviter tout problème d'alignement parfait des différents composants de l'équipage mobile de la pipette.Advantageously, a small mounting clearance will be maintained between the ball joint 56 of the control rod 24 and the upper surface of the spherical recess 54 of the clamp holder 42, so as to ensure that the frank limit stop up stroke is made at the contact between the clamp holder 42 and the adjusting screw 52 and not through the control rod 24 itself. It should be noted here that the separation of the clamp holder 16 and the rest of the control rod 24 makes it possible, in particular by making use of a ball-and-socket contact between these two elements, to avoid any problem of alignment perfect of the different components of the mobile pipette assembly.

Il est clair que le mode de réalisation particulier décrit concerne une pipette réglable, i.e. dont la butée supérieure de limitation de course de prélèvement est réglable par l'opérateur en agissant sur la vis réglable en position verticale 52. La présente invention ne se trouve toutefois pas limitée à un tel type de pipette réglable, mais peut également s'étendre à des pipettes fixes, i.e. à des pipettes dont la vis de réglage serait remplacée par une butée de limitation de course vers le haut qui reste fixe en position par rapport au corps de pipette 10.It is clear that the particular embodiment described relates to an adjustable pipette, ie the upper stop of limitation of sampling stroke is adjustable by the operator by acting on the adjustable screw in vertical position 52. The present invention is however not not limited to such a type of adjustable pipette, but may also extend to fixed pipettes, ie to pipettes whose adjusting screw would be replaced by an upstroke limit stop which remains fixed in position relative to the pipette body 10.

La butée de limitation vers le bas de la course utile de distribution de la pipette se trouve réalisée au niveau d'un épaulement 58 ménagé au voisinage de la partie inférieure du porte-pince 42. Cet épaulement 58 est apte à coopérer avec l'épaulement correspondant 48 ménagé au voisinage de l'extrémité inférieure du corps de pipette 10. Une telle position limite inférieure de l'organe porte-pince 16 se trouve illustrée en traits mixtes fins sur la figure 4. On notera que cette position est obtenue par compression complète du ressort principal 22.The stop limiting the downward direction of the useful dispensing stroke of the pipette is carried out at a shoulder 58 formed in the vicinity of the lower part of the clamp holder 42. This shoulder 58 is able to cooperate with the shoulder corresponding 48 formed in the vicinity of the lower end of the pipette body 10. Such a lower limit position of the clamp holder 16 is illustrated in thin dashed lines in FIG. 4. It will be noted that this position is obtained by compression complete with main spring 22.

L'orifice 60 de l'extrémité inférieure libre du corps de pipette 10 est agencé de manière à permettre le passage d'au moins une partie de l'organe de pincement 16 qui, en fin de course vers le bas, vient au contact d'une butée 62 ménagée à la surface intérieure de l'embout 26. Cette disposition particulière permet ainsi d'assurer l'éjection simultanée dudit embout 26 et du piston 18 qui reste prisonnier dans l'orifice capillaire 20.The orifice 60 of the free lower end of the pipette body 10 is arranged so as to allow the passage of at least part of the clamping member 16 which, at the end of the downward stroke, comes into contact with a stop 62 formed on the internal surface of the end piece 26. This particular arrangement thus makes it possible to ensure the simultaneous ejection of said end piece 26 and of the piston 18 which remains trapped in the capillary orifice 20.

Dans le mode de réalisation particulier décrit, les extrémités des branches élastiques 34 de la pince 32 dépassent librement de l'extrémité inférieure conique 44 du porte-pince 42. L'éjection de l'embout 26 de la pipette est donc obtenue en exerçant une force supplémentaire sur la tige de commande 24, qui permet de comprimer le second ressort 30. La compression de ce second ressort 30 provoque, au-delà de la position illustrée à la figure 4 i.e. lorsque le porte-pince 42 est en butée inférieure, dans un premier temps l'écartement des branches élastiques 34 qui permet la libération du piston 18. Dans un second temps, l'appui des extrémités libres des branches élastiques 34, à l'état écarté, sur la butée 62 ménagée sur la surface intérieure de l'embout 26 réalise ensuite l'éjection proprement dite de l'embout 26 dans l'orifice capillaire 20 duquel le piston 18 reste prisonnier. Selon un mode de réalisation avantageux de la présente invention, la butée 62 ménagée sur la surface intérieure de l'embout 26 se présente sous la forme d'une surface en décrochement vers l'intérieur.In the particular embodiment described, the ends of the elastic branches 34 of the clamp 32 freely project from the conical lower end 44 of the clamp holder 42. The ejection of the tip 26 of the pipette is therefore obtained by exerting a additional force on the control rod 24, which makes it possible to compress the second spring 30. The compression of this second spring 30 causes, beyond the position illustrated in FIG. 4 ie when the clamp holder 42 is in lower stop, in a first step the spacing of the elastic branches 34 which allows the release of the piston 18. In a second step, the support of the free ends of the elastic branches 34, in the separated state, on the stop 62 formed on the inner surface of the nozzle 26 then performs the actual ejection of the nozzle 26 in the capillary orifice 20 of which the piston 18 remains trapped. According to an advantageous embodiment of the present invention, the stop 62 formed on the interior surface of the endpiece 26 is in the form of a surface in inward recess.

De façon à assurer l'éjection simultanée de l'embout capillaire 26 et du piston 18, ledit piston et sa zone d'étanchéité 28 sont agencés de telle sorte qu'en fin de course complète de la tige de commande 24, le piston 18 ne s'échappe pas de l'orifice capillaire 20 par l'extrémité inférieure libre de ce dernier.In order to ensure the simultaneous ejection of the capillary endpiece 26 and the piston 18, said piston and its sealing zone 28 are arranged such that at the end of the complete travel of the control rod 24, the piston 18 does not escape from the capillary orifice 20 through the free lower end of the latter.

Dans le mode de réalisation particulier décrit, qui a donné pleine satisfaction dans la pratique, la surface intérieure de la partie supérieure de l'embout 26 présente au moins une zone annulaire 64 en saillie ou en retrait apte à coopérer élastiquement avec une zone annulaire 66 correspondante en retrait ou en saillie ménagée sur la surface latérale extérieure de la partie inférieure 14 du corps de pipette 10. Ces zones annulaires 64, 66 en saillie ou en retrait ont été agencées de manière à permettre une grande portée de guidage de l'embout 26 sur l'extrémité de la pipette, par exemple de l'ordre de 5 à 10 mm et de préférence de 6 à 8 mm. En revanche, ces zones annulaires 64, 66 en saillie ou en retrait sont également agencées de manière à assurer une faible course d'engagement et de dégagement de l'embout 26, de l'ordre de 2 mm.In the particular embodiment described, which has given full satisfaction in practice, the inner surface of the upper part of the endpiece 26 has at least one annular zone 64 projecting or recessed capable of cooperating elastically with an annular zone 66 corresponding recessed or protruding formed on the outer lateral surface of the lower part 14 of the pipette body 10. These annular zones 64, 66 projecting or recessed have been arranged so as to allow a large guide range of the nozzle. 26 on the end of the pipette, for example of the order of 5 to 10 mm and preferably from 6 to 8 mm. On the other hand, these annular zones 64, 66 projecting or recessed are also arranged so as to ensure a short stroke of engagement and disengagement of the endpiece 26, of the order of 2 mm.

En se reportant à nouveau à la figure 4 on notera que la compression du second ressort 30 entraîne tout d'abord une course libre de l'ordre de 5 dizième de millimètre au cours de laquelle les branches élastiques 34 de la pince 32 s'écartent et libèrent le piston 18. Puis, lorsque l'on continue de comprimer le second ressort 30, on obtient une seconde course de l'ordre de l'ordre de 2,5 mm qui assure précisément, par contact de l'extrémité des branches écartées 34 de la pince 32 avec la surface de butée 62 intérieure de l'embout 26, le dépassement de cette course de dégagement de l'embout qui est de l'ordre de 2 mm. Par voie de conséquence, lorsque la tige de commande 24 se trouve complètement comprimée, i.e. lorsqu'elle comprime à la fois le ressort principal 22 et le second ressort 30, l'enrobage d'étanchéité 28 du piston 18 dépasse de l'extrémité inférieure du tube capillaire 20 d'une longueur précisément égale à la distance a référencée sur la figure 4, i.e. sensiblement 5 dizième de millimètre.Referring again to FIG. 4, it will be noted that the compression of the second spring 30 firstly results in a free travel of the order of 5 tenths of a millimeter during which the elastic branches 34 of the clamp 32 move apart. and release the piston 18. Then, when one continues to compress the second spring 30, one obtains a second stroke of the order of the order of 2.5 mm which ensures precisely, by contacting the ends of the branches spaced apart 34 from the clamp 32 with the abutment surface 62 inside the endpiece 26, exceeding this disengagement stroke of the endpiece which is of the order of 2 mm. Consequently, when the control rod 24 is completely compressed, ie when it compresses both the main spring 22 and the second spring 30, the sealing coating 28 of the piston 18 protrudes from the lower end of the capillary tube 20 of a length precisely equal to the distance a referenced in Figure 4, ie substantially 5 tenths of a millimeter.

Claims (13)

1. A precision pipette of positive displacement for the removal and the distribution of small quantities of liquid, of the type comprising a substantially tubular pipette body (10), at the lower end of which is positioned a calibrated capillary (20), in which a piston (18) is displaced in a tight manner and against an upwards elastic restoring force exerted by a main spring (22), the displacement of the piston (18) being controlled by a control rod (24) projecting beyond the upper end of said pipette body, and a member (16) for pinching the upper end of the piston which is of the type having elastic arms which spread apart radially by displacement against the force exerted by a second spring (30) which is of a much greater resistance that that of the main spring and which is integral in translation with said control rod, characterised in that the pipette comprises a tip (26) having a calibrated capillary orifice (20) which is capable of cooperating by attachment with the free lower end of the pipette body (10), the orifice (60) of this latter end allowing the passage of at least a part of the pinching member (16) which, near the end of its downwards path, comes into contact with a stop (62) made on the inside surface of the tip (26) to ensure the simultaneous ejection of said tip and the piston (18) which remains imprisoned in the capillary orifice (20).
2. A pipette according to claim 1, characterised in that the inside surface of the top part of the tip (26) has at least one projecting or recessed annular zone (64) which is capable of resiliently cooperating with a corresponding recessed or projecting annular zone (66) made on the outside lateral surface of the lower part of the pipette body (10).
3. A pipette according to claim 2, characterised in that said projecting or recessed annular zones (64, 66) are arranged in order to allow a considerable guidance range of the tip (26) on the end of the pipette body of the order of from 5 to 10 mm, and a short engagement and disengagement path of the tip of the order of 2 mm.
4. A pipette according to one of claims 1 to 3, characterised in that the pinching member (16) is in the form of a separate cartridge comprising pincers (32) which are terminated at one end by elastic arms (34) and the other end (36) of which is screwed into a pincer support (38) which is capable of sliding, against a force exerted by the second spring (30), to some extent into the top part of the orifice of a pincer holder (42) which itself slides inside the body of the pipette (10) against the force exerted by the main spring (22), and the end of the elastic arms (34) has an enlarged surface which is tightly applied against the lower conical opening (44) of the pincer holder (42) under the action of said second spring (30).
5. A pipette according to claim 4, characterised in that the cooperation between the control rod (24) and the pinching member (16) takes place at the level of the upper surface of the pincer support (38).
6. A pipette according to claim 5, characterised in that the upper surface of the pincer support (38) has a spherical hollow (54) which is capable of cooperating with a lower swivel joint-shaped end (56) of the control rod (24).
7. A pipette according to one of claims 4 to 6, characterised in that the restriction stop towards the top of the useful path of the pipette is effected at the level of the free upper surface (50) of the pincer holder (42).
8. A pipette according to claim 7, characterised in that a slight assembly clearance exists between the swivel joint (56) of the control rod (24) and the upper surface of the spherical hollow (54) of the pincer support (38).
9. A pipette according to one of claims 4 to 8, characterised in that the restriction stop towards the bottom of the useful path of the pipette is effected at the level of a shoulder (58) made in the vicinity of the lower part of the pincer holder (42) and capable of cooperating with a corresponding shoulder (48) made in the vicinity of the lower end of the pipette body (10).
10. A pipette according to one of claims 4 to 9, characterised in that the ends of the elastic arms (34) of the pincers (32) freely project beyond the lower conical end (44) of the pincer holder (42).
11. A pipette according to claim 10, characterised in that the ejection of the tip (26) of the pipette is effected by compressing the second spring (30) causing, when the pincer holder (42) is at the lower stop, in a first time the elastic arms (34) to spread apart releasing the piston (18) and, causing in a second time the free ends of the elastic arms (34), in a spread-apart condition, to rest against the stop (62) made on the inside surface of the tip (26).
12. A pipette according to claim 11, characterised in that said stop (62) made on the inside surface of the tip (26) is in the form of an inwardly hooking surface.
13. A pipette according to one of claims 1 to 12, characterised in that the piston (18) is arranged so that at the end of the complete path of the control rod (24), the piston (18) does not escape from the capillary orifice (20) through the lower free end of the latter.
EP81400023A 1980-01-11 1981-01-09 Pipette with positive displacement Expired EP0032469B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT81400023T ATE3248T1 (en) 1980-01-11 1981-01-09 PIPETTE WITH POSITIVE SHIFT.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8000605 1980-01-11
FR8000605A FR2474340A1 (en) 1980-01-11 1980-01-11 PERFECTLY POSITIVE DISPLACEMENT PIPETTE

Publications (2)

Publication Number Publication Date
EP0032469A1 EP0032469A1 (en) 1981-07-22
EP0032469B1 true EP0032469B1 (en) 1983-05-11

Family

ID=9237457

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81400023A Expired EP0032469B1 (en) 1980-01-11 1981-01-09 Pipette with positive displacement

Country Status (6)

Country Link
US (1) US4362064A (en)
EP (1) EP0032469B1 (en)
JP (1) JPS56104247A (en)
AT (1) ATE3248T1 (en)
DE (1) DE3160228D1 (en)
FR (1) FR2474340A1 (en)

Families Citing this family (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4418580A (en) * 1981-10-13 1983-12-06 Sherwood Medical Company Pipettor mechanism and disposable tip and piston assembly
FR2515339A1 (en) * 1981-10-28 1983-04-29 Marteau D Autry Eric PRECISION PIPETTE WITH POSITIVE DISPLACEMENT
EP0197921A1 (en) * 1984-10-02 1986-10-22 DEVAUGHN, Donald H. Pipetting techniques using replaceable tips
US4672857A (en) * 1985-09-10 1987-06-16 Labindustries, Inc. Liquid microdispenser
US4824641A (en) * 1986-06-20 1989-04-25 Cetus Corporation Carousel and tip
US4748859A (en) * 1987-03-06 1988-06-07 Rainin Instrument Co., Inc. Disposable pipette tip
US4933148A (en) * 1988-08-04 1990-06-12 Brandeis University Pipetter barrel extension tube
FI86812C (en) * 1991-01-07 1992-10-26 Labsystems Oy Förträngningspipett
US5192511A (en) * 1991-05-31 1993-03-09 Tri-Continent Scientific, Inc. Pipette tip and piston
US6814936B1 (en) 1999-07-01 2004-11-09 Goran Enhorning Pipette assembly having a small volume disposable tip
FR2807345B1 (en) * 2000-04-07 2002-07-12 Gilson Sa SIMPLIFIED DISASSEMBLY PIPETTE
US6973845B2 (en) 2001-01-18 2005-12-13 Beckman Coulter, Inc. Low insertion force tip/mandrel
US7976793B2 (en) * 2003-11-27 2011-07-12 Gilson S.A.S. Electronic pipette
FR2874839B1 (en) * 2004-09-07 2007-03-02 Gilson Sas Soc Par Actions Sim PIPETTE COMPRISING A CONTROL CREW AND A MOBILE PISTON EQUIPMENT
US7641859B2 (en) * 2004-02-11 2010-01-05 Matrix Technologies Corporation Pipette tip mounting and ejection assembly and associated pipette tip
WO2005118129A1 (en) * 2004-05-27 2005-12-15 Stratos Biosystems, Llc Solid-phase affinity-based method for preparing and manipulating an analyte-containing solution
US8057756B2 (en) * 2005-01-28 2011-11-15 Parker-Hannifin Corporation Sampling probe, gripper and interface for laboratory sample management systems
US8192698B2 (en) * 2006-01-27 2012-06-05 Parker-Hannifin Corporation Sampling probe, gripper and interface for laboratory sample management systems
US8899118B1 (en) 2009-05-11 2014-12-02 Dan Seguin Multi-channel aspirating and dispensing instrument
FR2980123B1 (en) 2011-09-19 2013-10-11 Gilson Sas POSITIVE DISPLACEMENT PIPETTE HAVING AN IMPROVED EJECTION FUNCTION
CN102847569A (en) * 2012-08-29 2013-01-02 浙江硕华医用塑料有限公司 Disposable pipette
FR3003643B1 (en) * 2013-03-25 2015-04-17 Gilson Sas POSITIVE DISPLACEMENT PIPETTING SYSTEM HAVING ENHANCED EJECTION FUNCTION
FR3012883B1 (en) * 2013-11-07 2015-12-25 Gilson Sas POSITIVE DISPLACEMENT PIPETTING SYSTEM HAVING DESIGN FOR FACILITATING PREVENTION OF THE PISTON OF THE CAPILLARY PISTON ASSEMBLY
CN104502150B (en) * 2014-12-16 2017-01-04 武汉海王新能源工程技术有限公司 Used in nuclear power station radioactive liquid sample sampler and sampling method
EP3581275B1 (en) * 2016-06-15 2022-08-10 Hamilton Company Pipette tip coupling device and pipette tip assembly
DE102016121813A1 (en) * 2016-11-14 2018-05-17 Ika-Werke Gmbh & Co. Kg Pipette and method for adjusting a volume of a pipette to be pipetted

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2324366A1 (en) * 1975-09-18 1977-04-15 Labora Mannheim Gmbh PERFECTED LABORATORY PIPETTE
US4023716A (en) * 1976-04-20 1977-05-17 Justin Joel Shapiro Micro-dispensing liquid pipet

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2711124C2 (en) * 1977-03-15 1979-05-10 Labora Mannheim Gmbh Fuer Labortechnik, 6800 Mannheim Hand pipette

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2324366A1 (en) * 1975-09-18 1977-04-15 Labora Mannheim Gmbh PERFECTED LABORATORY PIPETTE
US4023716A (en) * 1976-04-20 1977-05-17 Justin Joel Shapiro Micro-dispensing liquid pipet

Also Published As

Publication number Publication date
DE3160228D1 (en) 1983-06-16
FR2474340A1 (en) 1981-07-31
EP0032469A1 (en) 1981-07-22
ATE3248T1 (en) 1983-05-15
JPS6366577B2 (en) 1988-12-21
JPS56104247A (en) 1981-08-19
FR2474340B1 (en) 1982-06-04
US4362064A (en) 1982-12-07

Similar Documents

Publication Publication Date Title
EP0032469B1 (en) Pipette with positive displacement
EP0078724B1 (en) Positive-displacement precision pipette
EP0776247B1 (en) Pipette for distributing successive volumes of a liquid
EP1293190B1 (en) Transfertset comprising a bottle, a cartridge and a device for two-way transfer of a liquid between the bottle and the cartridge
EP0623060B1 (en) Improved precompression pump
FR2545008A1 (en) Fluid-substance applicator with adjustable drying
EP0161980A2 (en) Make-up assembly, in particular for eye-lashes, for the use of a predetermined amount of make-up product
FR2589588A1 (en) APPARATUS FOR POLISHING MUTIPLE OPTICAL FIBERS
FR2706747A1 (en)
EP0299843B1 (en) Device for applying a liquid product, in particular for applying nail varnish
EP0014120B1 (en) Pipette with positive displacement
FR2507273A1 (en) DEVICE FOR FILLING A SHOCK ABSORBER, SPRING LEG, GAS SPRING OR OTHER SIMILAR PRESSURE FLUID APPARATUS
EP0485244A1 (en) Dispensing valve for a container with a fluid under pressure of a gas, and container equipped with such a valve
WO2020128269A1 (en) Device for dispensing a fluid product
EP3200923B1 (en) Hand-held pipette with ergonomic actuator
FR2714465A1 (en) Powder collection and distribution device.
EP0605275B1 (en) Assembly for spraying a liquid comprising a precompression pump
EP2982278A1 (en) Device for producing and fixing a food preparation
FR2637512A1 (en) Device for the automatic delivery of a product or of any object
EP0468899B1 (en) System to detachably connect a part to a fixed member, said part being in particular a wheel-cover
FR3012686A1 (en) ELECTRICAL APPARATUS COMPRISING A SPRING CONNECTION TERMINAL
FR2508089A1 (en) AUTOMATIC DOOR CLOSER WITH BUILT-IN BRAKING MEANS
FR2613266A1 (en) Tool for gripping and oriented screwing of a screw having a strap (U-clip)
FR2653643A1 (en) Stick for applying a pasty product
FR2776165A1 (en) Tool for implanting identification transponder chip in an animal

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

Designated state(s): AT BE CH DE GB IT LU NL SE

17P Request for examination filed

Effective date: 19810911

ITF It: translation for a ep patent filed

Owner name: SOCIETA' ITALIANA BREVETTI S.P.A.

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Designated state(s): AT BE CH DE GB IT LI LU NL SE

REF Corresponds to:

Ref document number: 3248

Country of ref document: AT

Date of ref document: 19830515

Kind code of ref document: T

REF Corresponds to:

Ref document number: 3160228

Country of ref document: DE

Date of ref document: 19830616

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

Ref country code: LU

Payment date: 19831228

Year of fee payment: 4

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

Ref country code: BE

Effective date: 19840109

Ref country code: AT

Effective date: 19840109

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

Ref country code: LU

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

Effective date: 19840131

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
BERE Be: lapsed

Owner name: MARTEAU D'AUTRY ERIC

Effective date: 19840109

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

Ref country code: NL

Effective date: 19840801

NLV4 Nl: lapsed or anulled due to non-payment of the annual fee
ITTA It: last paid annual fee
EAL Se: european patent in force in sweden

Ref document number: 81400023.8

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

Ref country code: SE

Payment date: 19970123

Year of fee payment: 17

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

Ref country code: CH

Payment date: 19970203

Year of fee payment: 17

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

Ref country code: SE

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

Effective date: 19980110

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

Ref country code: LI

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

Effective date: 19980131

Ref country code: CH

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

Effective date: 19980131

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

EUG Se: european patent has lapsed

Ref document number: 81400023.8

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

Ref country code: DE

Payment date: 19991228

Year of fee payment: 20

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

Ref country code: GB

Payment date: 20000105

Year of fee payment: 20

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

Ref country code: GB

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20010108

REG Reference to a national code

Ref country code: GB

Ref legal event code: PE20

Effective date: 20010108