EP3831486A1 - Pipette tip family comprising pipette tips for use with pipettes of a pipette family and pipette family comprising pipettes for use with pipette tips of a pipette tip family - Google Patents

Abstract

Pipette tip family comprising pipette tips of different tip types for use with pipettes of different pipette types of a pipette family, • each pipette tip comprising a tip cylinder • and a tip piston, • wherein the tip cylinder has a tubular body with a tip opening at the lower end, an attachment opening at the upper end, a seat area at the inner circumference for clamping on a clamping area of a pin of a pipette and a cylindrical piston barrel area between the tip opening and seat area • and the tip piston has a piston sealingly guided in the piston barrel area and an upwardly protruding piston rod for clamping in an axial bore with a hole at the lower end of a lifting rod a pipette, where pipette tips of the same subfamily are pipette tips of the same tip type or pipette tips of different tip types, in which the upper ends of the plunger rods are each Because the lowest position of the tip piston has the same positions with respect to the seat area • and pipette tips of different subfamilies have the upper ends of the piston rods in the respective lowest position of the tip piston at different positions with respect to the seat area, • so that the pipette tips of each subfamily with pipettes of a pipette type matched to them and not can be used for pipetting with pipettes of a pipette type of the pipette family that is not compatible with them

Description

The invention relates to a pipette tip family comprising pipette tips for use with pipettes of a pipette family and a pipette family comprising pipettes for use with pipette tips of a pipette tip family.

Pipettes are used in particular in scientific and industrial laboratories with medical, molecular biological and pharmaceutical fields of application for dosing selected volumes of liquids. The liquids can in particular be homogeneous (single-phase) liquids consisting of a single liquid component or a homogeneous mixture of several liquid components (solutions). Furthermore, the liquids can be heterogeneous (multiphase) mixtures of a liquid with another liquid (emulsions) or a solid (suspension).

Pipettes have a stem-shaped pipette housing with a pin (shoulder) at the lower end for clamping on a pipette tip. The pin is often a conical, cylindrical or partially conical and cylindrical projection and is also referred to as a "working cone". A pipette tip is a hollow tube with a tip opening at the lower end and an attachment opening at the upper end, with which the pipette tip can be clamped onto the pin. The liquid is taken up in the pipette tip and dispensed from it. The uptake and delivery of the liquid is controlled by means of the pipette. Fixed volume pipettes are used to pipette constant volumes. With variable pipettes, the volume to be dispensed can be set. A mechanical counter is used to display the set volume. To adjust the volume, the stroke of a drive device is by means of an adjusting device adjustable, which is coupled with the counter. The pipette tip is detached from the base after use and can be exchanged for a fresh pipette tip. In this way, cross-contamination can be avoided during subsequent pipetting operations.

Air-cushion pipettes have a piston-cylinder system in the pipette housing, which is connected to a through hole in the pin via a channel. Pipette tips for air-cushion pipettes (air-cushion pipette tips) do not have an integrated piston. By displacing the piston in the cylinder by means of the drive device, an air cushion is moved in order to suck in liquid into a pipette tip clamped onto the pin and to expel it therefrom. Disadvantages of air cushion pipettes are metering errors due to changes in the length of the air cushion due to the weight of the liquid sucked in and changes in temperature, air pressure and air humidity. Contamination of the pipette by aerosols can also be problematic.

Air-cushion pipettes are available in different sizes, each with only one matching air-cushion pipette tip with a certain nominal volume or several matching air-cushion pipette tips with different nominal volumes close together. It is known that air-cushion pipettes and air-cushion pipette tips are identified by a color code in order to facilitate correct assignment. There is a risk of misinterpretation by the user, so that he uses the wrong combination of a pipette with a pipette tip.

The US 6,749,812 B2 describes an air-cushion pipette with an automatic tip ejector which has a spring-loaded attachment for attaching pipette tips and a spring-loaded ejector sleeve guided thereon.

In addition, there is tip detection for pipette tips in which different tip types have a different basic configuration. With this tip recognition, different pipette tip types are recognized by a difference in the relative displacement of the attachment with respect to the ejector sleeve, which is detected by means of electronic sensors.

Positive displacement pipettes are used with pipette tips with an integrated piston (positive displacement pipette tips). This type of pipette has a pin for fastening the pipette tip and a drive device, which can be coupled to the integrated piston (tip piston), for moving the piston. The piston comes in direct contact with the liquid, eliminating the adverse effects of an air cushion. Positive displacement pipettes are particularly suitable for dosing liquids with high vapor pressure, high viscosity or high density and applications in molecular biology where freedom from aerosols is important in order to avoid contamination.

Air-cushion and positive displacement pipette tips for single use or for re-use are made of plastic or glass.

In the positive displacement pipette Biomaster® 4830 from Eppendorf AG, the drive device has a lifting rod for moving a piston in a pipette tip, which has a hollow lower lifting rod part and an upper lifting rod part inserted into the lower lifting rod part from above. The upper lifting rod part is connected to an operating element which protrudes from an upper end of the pipette housing. A Mastertip® pipette tip from Eppendorf AG with a nominal volume of 20 µl can be clamped onto a spigot of the pipette. By pressing the operating element, the lifting rod can be moved downwards so that an upper end of the piston rod of a tip piston of the Pipette tip is pressed into the lower lifting rod part. When moving the lifting rod down to a lower stop, a spring device is pretensioned. After the control element is relieved of pressure, the spring device moves the lifting rod up to an upper stop, the tip piston being taken along and liquid being sucked into the pipette tip. The sucked-in liquid can be dispensed by pressing the control element again as far as the lower stop. To release the pipette tip, the user must press the control element with increased force so that another spring device compresses, the upper lifting rod part is shifted downwards in the lower lifting rod part, the piston is pushed out of the lower lifting rod part and the pipette tip is pushed off the pin. The Biomaster® pipette and the Mastertip® pipette tips are designed for pipetting in the volume range from 1 µl to 20 µl.

The EP 2 574 402 B1 and the DE 199 48 818 A1 describe syringes with a coding and metering devices with sensors that scan the coding of the syringe used and output a display that is dependent on the type of syringe. The syringes are held by means of gripping levers or latches on a syringe flange of the syringe cylinder and grooves in the syringe plunger and are not clamped onto a pin and clamped in a hollow lifting rod like the positive displacement pipette tips.

Proceeding from this, the invention is based on the object of creating positive displacement pipette tips and air-cushion pipettes with an extended area of application. Application errors should be avoided as far as possible.

The object is achieved by a family of pipette tips according to claim 1. Advantageous embodiments of the pipette tip family are specified in the subclaims.

• wobei jede Pipettenspitze einen Spitzenzylinder
• und einen Spitzenkolben umfasst,
• wobei der Spitzenzylinder einen rohrförmigen Körper mit einer Spitzenöffnung am unteren Ende, einer Aufstecköffnung am oberen Ende, einem Sitzbereich am inneren Umfang zum Aufklemmen auf einen Klemmbereich eines Zapfens einer Pipette und einem zylindrischen Kolbenlaufbereich zwischen Spitzenöffnung und Sitzbereich aufweist
• und der Spitzenkolben einen abdichtend im Kolbenlaufbereich geführten Kolben und eine nach oben vorstehende Kolbenstange zum Einklemmen in einer axialen Bohrung mit einem Loch am unteren Ende einer Hubstange einer Pipette aufweist,
• wobei Pipettenspitzen derselben Unterfamilie Pipettenspitzen desselben Spitzentyps oder Pipettenspitzen unterschiedlichen Spitzentyps sind, bei denen die oberen Enden der Kolbenstangen in der jeweils tiefsten Stellung des Spitzenkolbens dieselben Positionen bezüglich des Sitzbereiches aufweisen
• und Pipettenspitzen unterschiedlicher Unterfamilien die oberen Enden der Kolbenstangen in der jeweils tiefsten Stellung des Spitzenkolbens an unterschiedlichen Positionen bezüglich des Sitzbereiches aufweisen,
• sodass die Pipettenspitzen jeder Unterfamilie mit Pipetten eines darauf abgestimmten Pipettentyps und nicht mit Pipetten eines darauf nicht abgestimmten Pipettentyps zum Pipettieren verwendet werden können.

The pipette tip family according to the invention comprises pipette tips of different tip types for use with pipettes of different pipette types of a pipette family,

• each pipette tip having a tip barrel
• and comprises a tip piston,
• wherein the tip cylinder has a tubular body with a tip opening at the lower end, an attachment opening at the upper end, a seat area on the inner circumference for clamping onto a clamping area of a pin of a pipette and a cylindrical piston barrel area between the tip opening and the seat area
• and the tip piston has a piston guided in a sealing manner in the piston running area and an upwardly projecting piston rod for clamping in an axial bore with a hole at the lower end of a lifting rod of a pipette,
• wherein pipette tips of the same subfamily are pipette tips of the same tip type or pipette tips of different tip types, in which the upper ends of the piston rods in the respective lowest position of the tip piston have the same positions with respect to the seat area
• and pipette tips of different subfamilies have the upper ends of the piston rods in the respective lowest position of the tip piston at different positions with respect to the seat area,
• so that the pipette tips of each subfamily can be used for pipetting with pipettes of a suitable pipette type and not with pipettes of a pipette type that is not suitable for them.

The object is also achieved by a family of pipettes according to claim 10. Advantageous embodiments of the pipette family are specified in the subclaims.

• ein stielförmiges Pipettengehäuse,
• einen Zapfen am unteren Ende des Pipettengehäuses mit einem Klemmbereich am äußeren Umfang zum Aufklemmen eines Sitzbereichs am inneren Umfang eines eine Aufstecköffnung am oberen Ende aufweisenden Spitzenzylinders einer Pipettenspitze und mit einer Durchgangsbohrung zum Einführen einer Kolbenstange eines Spitzenkolbens der Pipettenspitze,
• eine Antriebseinrichtung umfassend eine auf die Durchgangsbohrung ausgerichtete und in Längsrichtung des Zapfens verlagerbar im Pipettengehäuse geführte Hubstange mit einer axialen Bohrung und einem Loch am unteren Ende zum Einführen des obere Endes des Spitzenkolbens und einer Klemmeinrichtung zum Festklemmen des oberen Endes des Spitzenkolbens in der Bohrung und ein vom Pipettengehäuse vorstehendes, relativ zum Pipettengehäuse verlagerbares und mit der Hubstange gekoppeltes Bedienelement zum Verlagern eines abdichtend in einem Kolbenlaufbereich zwischen einer Spitzenöffnung am unteren Ende und dem Sitzbereich des Spitzenzylinders geführten Kolbens des Spitzenkolbens im Spitzenzylinder,
• ein bei entlastetem Bedienelement innerhalb der axialen Bohrung der Hubstange nach oben verlagerbares längliches erstes Abtastelement zum Abtasten des oberen Endes eines in die axiale Bohrung eingeführten Spitzenkolbens einer mit der Aufstecköffnung auf den Zapfen aufgeschobenen Pipettenspitze und
• eine mit dem ersten Abtastelement gekoppelte Steuereinrichtung, die ausgebildet ist, bei Abtastung einer Kolbenstange einer Pipettenspitze einer auf den Pipettentyp der Pipette abgestimmten Unterfamilie der Pipettenspitzenfamilie, bei der die oberen Enden der Kolbenstangen in der jeweils tiefsten Stellung des Spitzenkolbens dieselben Positionen bezüglich des Sitzbereiches aufweisen, die Pipette in einen das Pipettieren ermöglichenden Zustand zu versetzen und bei Abtastung einer Kolbenstange einer Pipettenspitze einer nicht auf den Pipettentyp abgestimmten Unterfamilie, bei der die oberen Enden der Kolbenstangen in der jeweils tiefsten Stellung des Spitzenkolbens andere Positionen bezüglich des Sitzbereichs als die Pipettenspitzen der auf den Pipettentyp abgestimmten Unterfamilie aufweisen, in einen das Pipettieren nicht ermöglichenden Zustand zu versetzen.

The pipette family according to the invention comprises pipettes of different pipette types for use with pipette tips of different tip types of a pipette tip family, each pipette comprising the following features:

• a stem-shaped pipette housing,
• a pin at the lower end of the pipette housing with a clamping area on the outer circumference for clamping a seat area on the inner circumference of a tip cylinder of a pipette tip, which has an attachment opening at the upper end, and with a through-hole for inserting a piston rod of a tip piston of the pipette tip,
• a drive device comprising a lifting rod aligned with the through hole and displaceably guided in the longitudinal direction of the pin in the pipette housing with an axial bore and a hole at the lower end for inserting the upper end of the tip piston and a clamping device for clamping the upper end of the tip piston in the bore and a The operating element protruding from the pipette housing, can be displaced relative to the pipette housing and is coupled to the lifting rod for displacing a piston of the tip piston in the tip cylinder, which is sealingly guided in a piston barrel area between a tip opening at the lower end and the seat area of the tip cylinder,
• an elongated first scanning element, which can be displaced upward within the axial bore of the lifting rod when the operating element is relieved, for scanning the upper end of a tip piston inserted into the axial bore of a pipette tip pushed onto the pin with the plug-on opening and
• a control device coupled to the first scanning element, which is designed, when scanning a piston rod of a pipette tip of a subfamily of the pipette tip family matched to the pipette type of the pipette, in which the upper ends of the piston rods have the same positions with respect to the seat area in the respective lowest position of the tip piston, to put the pipette in a state that enables pipetting and when a piston rod of a pipette tip of a subfamily not matched to the pipette type is scanned, in which the upper ends of the piston rods in the respective lowest position of the tip piston have different positions with respect to the seat area than the pipette tips of the Have subfamily matched to the type of pipette to put in a state that does not allow pipetting.

In the case of the pipette tip family according to the invention, the range of application is expanded in that it includes pipette tips with an integrated piston of different tip types. For example, in a pipette tip family in which the different tip types differ from one another by their nominal volume, the range of pipettable volumes is increased and / or the accuracy with which different volumes can be pipetted is improved. In addition, the range of application of the pipette tip family is expanded in that it comprises several subfamilies, each of pipette tips of the same tip type or pipette tips different tip type are formed, in which the upper ends of the piston rods in the lowest position of the piston have the same positions with respect to the seat area. This enables the use of pipette tips of different tip types with the same pipettes of a pipette type matched to them.

In the case of the pipette family according to the invention, the range of application is expanded in that these pipettes include different pipette types. For example, in a pipette family in which the various pipette types differ in that they can be used with pipette tips with different nominal volumes, the range of pipettable volumes is increased and / or the accuracy with which different volumes can be pipetted is improved. In addition, the area of application is increased by the fact that every pipette of a certain pipette type can be used with all pipette tips of a subfamily that is matched to it. This means that pipette tips of different tip types can be used with the same pipette.

Mix-ups, incorrect dosing and other application errors are avoided by the fact that the pipette tips of each subfamily can only be used with pipettes of a specific pipette type and the pipette of a certain pipette type can only be used with pipette tips of a matching subfamily.

Pipetting is the process of picking up liquid in pipette tips and dispensing liquid from pipette tips using pipettes. With the use of pipette tips with pipettes, holding pipette tips on pipettes and moving pipette tips held on pipettes becomes a thing of the past Moving pipettes and pipetting with the help of pipette tips and pipettes are referred to.

According to a further embodiment, pipette tips of different tip types differ from one another by one or more of the following features: nominal volume, shape, dimensions, material, coating of the surface, with or without treatment of the surface, electrically insulating or electrically conductive, degree of purity. The invention extends the field of application of pipette tips, in particular with regard to the aforementioned features, and at the same time avoids application errors.

According to a further embodiment, the pipette tips have a collar with the plug-on opening at the upper end and the seat area on the inner circumference of the collar. The collar is particularly advantageous for holding pipette tips on a carrier (rack) when storing, transporting and clamping pipette tips onto the pegs of pipettes. Furthermore, the collar can be advantageous for precise positioning of the pipette tip on the peg and for separating the pipette tip from the peg.

Another embodiment comprises at least one subfamily with pipette tips of different tip types, each of these pipette tips having a collar with a height characteristic of the tip type and these pipette tips are designed with their seat area on the inner circumference of the collar on the same clamping area of a pin of a pipette of the same pipette type to be clamped so that they stand up with their collar different heights on the pin. The height of the collar is preferably the distance that the upper edge of the collar has in the vertical direction from the seat area of the pipette tip. With this type of design Pipette tips with collars of different heights control a scanning element of a scanning device of the pipette in such a way that the scanning device sets a display of a display device of the pipette that is dependent on the type of pipette tip. As a result, when pipette tips of different tip types are clamped onto the pin of the pipette, the display is set in such a way that it indicates the tip type of the respectively attached pipette tip. In particular, this allows the volume displayed by the pipette to be set to the nominal volume of an attached pipette tip. Pipette tips with collars of different heights are defined in claim 8 and the corresponding parts of the description and the exemplary embodiments of FIG EP 18 168 763.3 described. Pipettes with a scanning device for scanning collars of different heights are described in claims 1 to 16, the corresponding parts of the description and the exemplary embodiments of the same patent application. In this regard, reference is made to the above patent application, the content of which is hereby incorporated into this application.

According to a further embodiment, the nominal volumes of pipette tips of different tip types for use with matched pipettes of the same pipette type differ from one another by one or more powers of ten. This is advantageous for the automatic setting of a volume display by means of a mechanical counter by adjusting a marking to different decimal places of the counter.

According to a further embodiment, the seat area of the pipette tips has a bead running around the inner circumference of the tip cylinder for snapping into an annular groove of the clamping area surrounding the outer circumference of the pin of a pipette and / or the seat area of the pipette tips has an annular groove running around the inner circumference for snapping one on outer circumference of the pin of a pipette encircling bead of the clamping area. This keeps the pipette tips securely on the spigot. Furthermore, this can ensure that a defined position of the pipette tips on the pin is maintained. This contributes to the fact that the pipette tip of each subfamily can only be used with a specially designed pipette. According to a preferred embodiment, the positions occupied by the upper ends of the piston rods in the respective lowest position of the tip piston relate to the bead or the annular groove of the pipette tips.

According to a further embodiment, the pipette tip family comprises pipette tips of at least one tip type of a first subfamily with an upper end of the piston rod arranged in the deepest position of the tip piston in a first position above a bead surrounding the inner circumference of the tip cylinder for use with matched pipettes of a first pipette type , Pipette tips of at least one further tip type of a second subfamily with an upper end of the piston rod in the deepest position of the tip piston in a second position below an upper end of the piston rod arranged on the inner circumference of the tip cylinder for use with matching pipettes of a second pipette type and pipette tips of at least one other Tip type of a third subfamily with one in the lowest position of the tip piston in a third position between the first and second positions Thin upper end of the piston rod for use with a matching pipette of a third pipette type. In this embodiment, errors due to incorrect use of pipette tips are particularly reliably avoided. According to a further embodiment, the upper end of the piston rod of the pipette tips of the third subfamily is arranged in the respective lowest position of the tip piston at approximately the same level as the bead.

According to a further embodiment, the pipette tip family comprises pipette tips with nominal volumes of 10 µl and 100 µl of a first subfamily for use with pipettes of a first pipette type, pipette tips with nominal volumes of 25 µl and 250 µl of a second subfamily for use with pipettes of a second pipette type and a pipette tip with a nominal volume of 1000 µl of a third subfamily for use with pipettes of a third pipette type.

According to a further embodiment, the pipette tip family comprises pipette tips in which the piston rods in a lower rod section with a larger outer diameter have a clamping groove for clamping a clamping element of the lifting rod and above that in an upper rod section have a smaller diameter than the lower rod section, so that the upper rod section does not have a diameter of the clamping element of the lifting rod can be clamped. This ensures that the pipette tip can only be connected to the type of pipette intended for it.

According to a further embodiment, the pipette tip family comprises pipette tips in which the tip piston has a stop for support at the edge of a hole at the lower end of the lift rod below a clamping groove for clamping a clamping element of the lifting rod and / or below a lower rod section for clamping a clamping element of the lifting rod. The stop prevents the piston rod from being pushed so deep into the receptacle of the lifting rod that the liquid picked up by the pipette tip cannot be completely dispensed. Without the stop, this would occur, for example, when highly viscous liquid is pipetted. When dispensing the highly viscous liquid from the pipette tip Due to the high flow resistance of the liquid, a high force acts on the piston, which could push it deeper into the receptacle. This is prevented by placing the stop on the edge of the hole at the lower end of the lifting rod. This avoids pipetting errors.
According to a further embodiment, the pipette tip family comprises pipette tips made of one or more plastics. According to a further embodiment, the pipette tips are made of polypropylene and / or polyethylene. According to a further embodiment, the tip cylinders are made of polypropylene and the tip pistons are made of polyethylene.

According to a further embodiment of the pipette family according to the invention, the control device of the pipette of at least one pipette type is a mechanical control device. According to a further embodiment, the pipettes of all pipette types have a mechanical control device.

According to a further embodiment, the control device of each pipette of the pipette family is designed (i.) When scanning a piston rod, which has the length of the piston rod of a pipette tip of a subfamily matched to the pipette, to put the drive device into a state enabling pipetting and to clamp the To allow pipette tip on the pin and lifting rod and / or (ii) when scanning a piston rod that is shorter than the piston rod of a pipette tip of a subfamily matched to the pipette, to put the drive device in a state that does not allow pipetting and / or (iii.) when scanning a piston rod that is longer than the piston rod of a pipette tip of a subfamily matched to the pipette, to prevent the pipette tip from jamming on the peg and / or the lifting rod. This ensures that the pipette Each pipette type can only be used with pipette tips from a matching subfamily.

• eine Abwurfeinrichtung umfassend einen drehbar im Pipettengehäuse gelagerten Kurventräger,
• ein an einer ersten Kurve am Umfang des Kurventrägers geführtes zweites Abtastelement an dem länglichen ersten Abtastelement, das in Längsrichtung des Zapfens verlagerbar im Pipettengehäuse geführt ist und
• ein mit dem Kurventräger verbundenes, vom Pipettengehäuse vorstehendes und relativ zum Pipettengehäuse drehbares Bedienelement,
• wobei die Abwurfeinrichtung ausgebildet ist, durch Drehen des Bedienelementes aus einer Pipettierstellung in eine Abwurfstellung den Kurventräger zu drehen, wobei die erste Kurve das zweite Abtastelement so nach unten verlagert, dass das längliche erste Abtastelement eine auf dem Zapfen gehaltene Pipettenspitze vom Zapfen abdrückt und
• die Abwurfeinrichtung ausgebildet ist, bei Abtastung einer Kolbenstange durch das längliche erste Abtastelement, die kürzer als die Kolbenstange einer Pipettenspitze einer auf die Pipette abgestimmten Unterfamilie ist, das Bedienelement nicht aus der Abwurfstellung in die Pipettierstellung zu drehen, sodass ein Pipettieren verhindert wird.

According to a further embodiment, the control device of each pipette of the pipette family has the following features:

• an ejection device comprising a cam support rotatably mounted in the pipette housing,
• a second scanning element, guided on a first curve on the circumference of the curve support, on the elongated first scanning element, which is guided in the pipette housing such that it can be displaced in the longitudinal direction of the pin and
• an operating element connected to the curve support, protruding from the pipette housing and rotatable relative to the pipette housing,
• wherein the ejection device is designed to rotate the cam carrier by rotating the operating element from a pipetting position into a ejection position, the first curve displacing the second scanning element downward so that the elongated first scanning element pushes a pipette tip held on the pin from the pin and
• the ejection device is designed not to rotate the operating element from the ejection position into the pipetting position when a piston rod is scanned by the elongated first scanning element, which is shorter than the piston rod of a pipette tip of a subfamily matched to the pipette, so that pipetting is prevented.

In this embodiment, the control device is at the same time an ejection device which can be used to release used pipette tips from the pipette. By turning the operating element from the pipetting position to the ejection position, a pipette tip can be pressed off the spigot. At the Attaching a pipette tip to the pin, the operating element is rotated from the ejection position into the pipetting position when the first scanning element scans the piston rod of a subfamily matched to the pipette. If the piston rod is shorter, the operating element is not turned into the pipetting position, so that the ejection device prevents pipetting. In this embodiment, even if the piston rod is so short that it is not scanned by the elongated first scanning element, the operating element is not rotated from the ejection position into the pipetting position, so that pipetting is prevented.

• der Zapfen weist Mittel zum formschlüssigen Verbinden mit einer Pipettenspitze auf, sodass eine Pipettenspitze unter elastischer Verengung des Zapfens und/oder unter elastischer Aufweitung der Pipettenspitze vor ihrer formschlüssigen Verbindung mit dem Zapfen auf den Zapfen aufschiebbar ist,
• eine Sperreinrichtung umfassend eine konzentrisch zum Zapfen angeordnete Sperrhülse, eine von der Sperrhülse nach oben vorstehende Steuerstange, die in Richtung des Zapfens im Pipettengehäuse verlagerbar geführt ist, ein von der Steuerstange vorstehendes drittes Abtastelement und eine zweite Kurve am Umfang des Kurventrägers , an der das dritte Abtastelement geführt ist und die so ausgebildet ist, dass bei Anordnung des Bedienelements in der Pipettierstellung die Sperrhülse in einer Sperrstellung den Zapfen innen begrenzt und/oder die Pipettenspitze außen begrenzt, sodass die Sperrhülse ein Ablösen einer formschlüssig mit dem Zapfen verbunden Pipettenspitze vom Zapfen verhindert,
• wobei durch Drehen des Bedienelements aus der Pipettierstellung in die Abwurfstellung die Sperrhülse nach oben verlagerbar ist, sodass der Zapfen und/oder die Pipettenspitze zumindest teilweise freigegeben wird und das längliche erste Abtastelement die Pipettenspitze vom Zapfen abdrückt und bei Abtastung einer Kolbenstange durch das längliche erste Abtastelement, die länger als die Kolbenstange einer Pipettenspitze einer auf die Pipette abgestimmten Unterfamilie ist, die Sperrhülse in die Sperrstellung verlagerbar ist, sodass ein Festklemmen der Pipettenspitze an der Pipette verhindert wird.

According to a further embodiment, the control device of each pipette of the pipette family has the following features:

• the pin has means for a positive connection with a pipette tip, so that a pipette tip can be pushed onto the pin with elastic narrowing of the pin and / or with elastic expansion of the pipette tip before its positive connection with the pin,
• a locking device comprising a locking sleeve arranged concentrically to the pin, a control rod protruding upward from the locking sleeve, which is displaceably guided in the direction of the pin in the pipette housing, a third scanning element protruding from the control rod and a second curve on the circumference of the cam carrier, on which the third The scanning element is guided and which is designed such that when the operating element is arranged in the pipetting position, the locking sleeve in a locking position limits the inside of the pin and / or limits the pipette tip on the outside, so that the locking sleeve prevents a pipette tip connected positively to the pin from becoming detached from the pin,
• whereby the locking sleeve can be displaced upwards by rotating the operating element from the pipetting position to the ejection position, so that the pin and / or the pipette tip is at least partially released and the elongated first scanning element presses the pipette tip off the pin and when a piston rod is scanned by the elongated first scanning element , which is longer than the piston rod of a pipette tip of a subfamily matched to the pipette, the locking sleeve can be displaced into the locking position so that the pipette tip is prevented from jamming on the pipette.

In this embodiment, the control device is at the same time a device for the form-fitting connection of a pipette tip with the pipette, so that the pipette tip can be held particularly securely on the pipette. When a pipette tip is attached to the pin, in which the piston rod has the length of a pipette tip matched to the pipette, the locking sleeve is rotated into the locking position by the first scanning element and the pipette tip is thereby secured on the pin. If the piston rod is longer than the piston rod of a pipette tip of a subfamily matched to the pipette, the locking sleeve is shifted to the locking position before the pipette tip is sufficiently pushed onto the pin, i.e. when the pin narrows so elastically and / or the pipette tip expands so elastically is that the locking sleeve cannot be moved into the locking position. This prevents the pipette tip from being pushed onto the spigot, so that the pipette tip cannot be connected to the pipette in such a way that pipetting is possible. In addition, the operating element is not moved from the ejection position to the pipetting position, which also prevents pipetting.

According to a further embodiment, the control device of each pipette comprises a stop which limits the sliding of pipette tips onto the peg, so that when a pipette tip is pushed onto the peg with a collar that is longer than the collars of the pipette tips of a subfamily matched to the pipette, the Stop prevents the pipette tip from jamming on the pipette. In this embodiment, the control device also ensures that pipette tips that are matched to the pipette have a defined seat on the pin. In this way, the forces for clamping the pipette tips onto the pegs and for releasing the pipette tips from the pegs can also be limited. The stop can in particular be formed by a surface on the underside of the pipette housing, by a shoulder of the pin or by a surface on the underside of a fourth scanning element which can be displaced against a further stop of the pipette.

According to a further embodiment, the pin has a specific shape. According to a further embodiment, the pin is a conical, cylindrical or partially conical and cylindrical projection.

According to a further embodiment, the pin has several conical sections with different cone angles. In addition, the pin can have at least one cylindrical section.

The invention further relates to a pipette system consisting of a family of pipette tips according to one of Claims 1 to 9 and a family of pipettes according to one of Claims 10 to 14.

Fig. 1

eine Direktverdrängerpipette mit einer auf dem Zapfen aufgesteckten Pipettenspitze teilweise geschnitten in einer Perspektivansicht;

Fig. 2

geschlitzter Zapfen mit innenliegender Sperrhülse derselben Direktverdrängerpipette mit aufgesteckter Pipettenspitze in einer vergrößerten Perspektivansicht;

Fig. 3

dieselbe Anordnung in einer Seitenansicht;

Fig. 4

dieselbe Anordnung einen Längsschnitt;

Fig. 5

Direktverdrängerpipette von Fig. 1 in einem Sprengbild;

Fig. 6

Direktverdrängerpipette von Fig. 1 in einem Sprengbild ohne Pipettengehäuse;

Fig. 7

Drehhülse mit Abwurfstange und der Sperrhülse derselben Direktverdrängerpipette in der Ausgangsstellung in einer Perspektivansicht;

Fig. 8

dieselbe Direktverdrängerpipette in der Ausgangsstellung teilweise geschnitten in einer Seitenansicht;

Fig. 9

dieselbe Direktverdrängerpipette beim Pipettieren teilweise geschnitten in einer Seitenansicht;

Fig. 10

dieselbe Direktverdrängerpipette beim Abwerfen teilweise geschnitten in einer Seitenansicht;

Fig. 11

dieselbe Direktverdrängerpipette in einer Vorderansicht;

Fig. 12a-e

Pipettenspitzenfamilie mit drei Unterfamilien und drei Unterfamilien umfassend eine Pipettenspitze mit einem Nennvolumen von 10 µl (Fig. 12a), 25 µl (Fig. 12b), 100 µl (Fig. 12c), 250 µl (Fig. 12d) und 1000 µl (Fig. 12e) jeweils in einem Längsschnitt;

Fig. 13a-e

dieselbe Direktverdrängerpipette ausgebildet für das Pipettieren von Proben bis zu 1000 µl mit einer aufgesteckten Pipettenspitze mit einem Nennvolumen von 1000 µl (Fig. 13a), 10 µl (Fig. 13b), 100 µl

Fig. 14a-e

(Fig. 13c), 25 µl (Fig. 13d) und 250 µl (Fig. 13e) jeweils in einem teilweisen Längsschnitt; dieselbe Direktverdrängerpipette ausgebildet für das Pipettieren von Proben bis zu 100 µl bei einer aufgesteckten Pipettenspitze mit einem Nennvolumen von 10 µl (Fig 14a), 100 µl (Fig. 14b), 25 µl (Fig 14c), 250 µl (Fig. 14d) und 1000 µl (Fig. 14e), jeweils in einem teilweisen Längsschnitt;

Fig. 15a-e

dieselbe Direktverdrängerpipette ausgebildet für das Pipettieren von Proben bis 250 µl mit einer aufgesteckten Pipettenspitze mit einem Nennvolumen von 25 µl (Fig. 15a), 250 µl (Fig. 15b), 10 µl (Fig. 15c), 100 µl (Fig. 15d) und 1000 µl (Fig. 15e) jeweils in einem teilweisen Längsschnitt;

Fig. 16

unteres Ende der Direktverdrängerpipette mit einer auf den Zapfen aufgesteckten Pipettenspitze mit Anschlag in einem Längsschnitt.

The invention is explained below with reference to the attached drawings of an exemplary embodiment. In the drawings show:

Fig. 1

a positive displacement pipette with a pipette tip attached to the pin, partially sectioned in a perspective view;

Fig. 2

slotted pin with internal locking sleeve of the same positive displacement pipette with attached pipette tip in an enlarged perspective view;

Fig. 3

the same arrangement in a side view;

Fig. 4

the same arrangement a longitudinal section;

Fig. 5

Positive displacement pipette from Fig. 1 in an exploded view;

Fig. 6

Positive displacement pipette from Fig. 1 in an exploded view without pipette housing;

Fig. 7

Rotary sleeve with ejector rod and the locking sleeve of the same positive displacement pipette in the starting position in a perspective view;

Fig. 8

the same positive displacement pipette in the starting position partially cut in a side view;

Fig. 9

the same positive displacement pipette during pipetting, partially sectioned in a side view;

Fig. 10

the same positive displacement pipette when ejected, partially cut in a side view;

Fig. 11

the same positive displacement pipette in a front view;

Figures 12a-e

Pipette tip family with three subfamilies and three subfamilies comprising a pipette tip with a nominal volume of 10 µl ( Figure 12a ), 25 µl ( Figure 12b ), 100 µl ( Figure 12c ), 250 µl ( Figure 12d ) and 1000 µl ( Figure 12e ) each in a longitudinal section;

Figures 13a-e

the same positive displacement pipette designed for pipetting samples up to 1000 µl with an attached pipette tip with a nominal volume of 1000 µl ( Figure 13a ), 10 µl ( Figure 13b ), 100 µl

Figures 14a-e

( Figure 13c ), 25 µl ( Figure 13d ) and 250 µl ( Figure 13e ) each in a partial longitudinal section; the same positive displacement pipette designed for pipetting samples up to 100 µl with an attached pipette tip with a nominal volume of 10 µl ( Figure 14a ), 100 µl ( Figure 14b ), 25 µl ( Figure 14c ), 250 µl ( Figure 14d ) and 1000 µl ( Figure 14e ), each in a partial longitudinal section;

Figures 15a-e

the same positive displacement pipette designed for pipetting samples up to 250 µl with an attached pipette tip with a nominal volume of 25 µl ( Figure 15a ), 250 µl ( Figure 15b ), 10 µl ( Figure 15c ), 100 µl ( Figure 15d ) and 1000 µl ( Figure 15e ) each in a partial longitudinal section;

Fig. 16

Lower end of the positive displacement pipette with a pipette tip attached to the pin with a stop in a longitudinal section.

In the present application, the terms "above" and "below" as well as "vertical" and "horizontal" and terms derived therefrom, such as "above" and "below", "upright" and "upside down" and " one above the other "refers to an arrangement of the pipette in which the pin is oriented vertically and is located at the downward-facing end of the pipette housing. With regard to the pipette tips, these details relate to a vertical alignment of the central axis of the pipette tips, the tip opening being arranged at the bottom and the plug-on opening at the top.

According to Fig. 1 If a pipette 1 designed as a positive displacement pipette has a rod-shaped (for example cylindrical) pipette housing 2. A hollow cylindrical shaft 3 projects downward from the lower end of the pipette housing 2. A pin 4 projects downward from the lower end of the shaft 3, which according to FIG Fig. 1 and 4th a Has through hole 5 with a through hole at the lower end. The inside diameter of the through hole 5 is smaller than the inside diameter of the shaft 3.

The pin 4 has an upper pin section 6 with the shape of a hollow cone and below it a lower pin section 7 with the shape of a hollow cone.

The upper journal section 6 has a smaller cone angle than the lower journal section 7. Between the upper journal section 6 and the lower journal section 7, an annular groove 8 runs around on the outer circumference of the journal 4.

The upper pin section 6, the annular groove 8 and the lower pin section 7 form the first means for positively connecting the pipette to a pipette tip. The annular groove 8 forms a clamping area 9 for a corresponding bead of a pipette tip.

Furthermore, the pin 4 has slots 10, 11 running in its longitudinal direction, preferably three, which are evenly spaced around the circumference of the pin 4. The slots 10, 11 extend from the lower end along the pin 4.

According to Fig. 1 , 5 and 6th a drive device 12 is present in the pipette housing 2, which comprises a transmission element 13 in the form of a transmission rod 14, a transmission mechanism 15 and a drive element 16 in the form of a lifting rod 17. Furthermore, the drive device 12 comprises an operating element 18 in the form of an operating lever 19, which is firmly connected to a carrier plate 21 via a web 20.

According to Fig. 6 the carrier plate 21 has an oval shape with a wide rounded end and a narrow rounded end, the operating lever 19 protruding from the edge of the narrow rounded end. In addition to this edge, the carrier plate 21 has a first curved slot 22 which runs approximately parallel to the contour of the narrow rounded end. Furthermore, the carrier plate 21 has a rectangular first edge recess 23 in the middle of the first curved slot 22 on the side of the narrow rounded end.

According to Fig. 1 and 5 the lifting rod 17 is guided into the shaft 3 and the pin 4 from above. According to Fig. 4 it is hollow and provided with an axial bore 24 which extends as far as a hole 25 in the lower end of the lifting rod 17. Furthermore, it has a longitudinal slot 26 which starts at its upper end and runs in the longitudinal direction and ends in front of its lower end. Due to the longitudinal slot 26, the lifting rod 17 has a C-shaped cross section. Its lower end forms a receptacle 27 for the upper end of a piston rod.

According to Fig. 13 the lifting rod 17 has a circumferential clamping spring groove 28 in the unslotted area next to its lower end. Inside the clamping spring groove 28 there are clamping slots 29.1, 29.2 on two diametrically opposite sides in the lifting rod 17, in which the clamping spring groove 28 is open to the inside of the lifting rod 17. A clamping spring 30 is inserted into the clamping spring groove 28 and engages through the clamping slots 29.1, 29.2 into the inner cross section of the lifting rod 17.

The transmission mechanism 15 is designed such that when the operating lever 19 is displaced downward one after the other, between which the operating lever 19 is displaced upward, the lifting rod 17 is alternately displaced upward and downward. As a result, by pressing the operating lever 19 downwards the lifting rod 17 are moved from a lower position to an upper position, the lifting rod 17 retains the upper position during the subsequent upward displacement of the operating lever 19 and the lifting rod 17 is shifted downward again by a subsequent pressing of the operating lever 19. This can be repeated as often as you like.

According to Fig. 1 , 5 and 6th the pipette 1 is provided with an ejection device 31. This comprises a cam support 32 which is rotatably supported in the pipette housing 2 and which is designed as a hollow cylindrical rotary sleeve 33. The outer circumference of the rotary sleeve 33 is rotatably mounted, for example, on the inner circumference of the pipette housing 2 and is supported at the upper and lower end between shoulders of steps on the inner circumference of the pipette housing 2, so that it cannot be displaced in the axial direction in the pipette housing 2. The axis of rotation of the rotary sleeve 33 coincides with the longitudinal axis of the pipette housing 2 and the longitudinal axis of the pin 4.

The rotating sleeve 33 has recesses 34, 35 parallel to its axis of rotation on two diametrically opposite sides which extend from the upper edge of the rotating sleeve 33 and end at a distance from its lower edge. Below the recesses, the rotating sleeve 33 thus consists of a circular base 36 and above it consists of two sectors 37, 38 of a circular ring that are diametrically opposite one another and which laterally delimit the two recesses 34, 35.

A first curve 39 and a second curve 40 are arranged on the outer circumference of the circular base 36 of the rotary sleeve 33. The first curve 39 is designed as a first groove 41 in the form of an inverted Y (turned upside down). The vertical part 42 of the Y extends far up on a sector 37 to shortly in front of the upper edge of the sector 37. The second curve 40 is a second groove 43 on the outer circumference of the base 36 of the rotating sleeve 33 with the shape of an upright V. The first curve 39 and the second curve 40 are offset by 90 ° to one another arranged on the circumference of the rotary sleeve. The first curve 39 and the second curve 40 each extend over an angular range of less than 90 ° over the circumference of the rotary sleeve 33.

According to Fig. 1 , 5 and 6th the ejection device 31 comprises a first elongated sensing element 44 (ejection rod), which comprises a strip-shaped upper ejection rod section 45 and a cylindrical lower ejection rod section 46. The upper and lower ejector rod sections 45, 46 are arranged parallel to one another and laterally offset from one another. The lower end of the upper ejector rod section 45 is connected to the upper end of the lower ejector rod section 46 via a strip-shaped connecting rod section 47 inclined obliquely to the two ejector rod sections. A second scanning element 48 in the form of a first guide pin 49 protrudes vertically from the inside of the upper ejection rod section 45. The first scanning element 44 is preferably formed in one piece, for example from a rigid plastic or from metal.

According to Fig. 1 , 4th and 7th the first scanning element 44 is guided with the first guide pin 49 in the first groove 41, engages with the connecting rod section 47 through the longitudinal slot 26 of the lifting rod 17 and extends with the lower ejection rod section 46 within the lifting rod 17 to just before the lower end of the same.

According to Fig. 1 , 4th , 5 and 6th the pipette 1 comprises a locking device 50 which comprises a locking sleeve 51 and a strip-shaped control rod 52 parallel thereto. The The upper end of the locking sleeve 51 and the lower end of the control rod 52 are connected to one another via a second connecting rod section 53 which is inclined at an angle to the locking sleeve 51 and to the control rod 52. A third scanning element 54 in the form of a second guide pin 55 protrudes from the inside of the control rod 52.

According to Fig. 1 and 7th the second guide pin 55 is guided in the second groove 43. According to Fig. 1 and 4th the locking sleeve 51 is inserted into the shaft 3 from above and rests against the inside of the pin 4. The lifting rod 17 and the elongated first scanning element 44 are inserted into the locking sleeve 51 from above.

The operating element 18 is pushed with the first curved slot 22 onto the sector 37 of the rotary sleeve 33 on which the first groove 41 extends. According to Fig. 1 , 6th and 7th the rotary sleeve 33 is connected at the top to a support ring 56 which bridges the two sectors 37, 38 and stabilizes the rotary sleeve 33. The support ring 56 has on the outer edge a downwardly protruding jacket 57 which laterally surrounds the two sectors 37, 38 at the outer edges. It also has a second curved slot 58 which receives the upper edge of the sector 38 which is not provided with a groove 41, 43. On the diametrically opposite side of the jacket 57 there is a downwardly opened rectangular second edge recess 59 which is designed to accommodate the web 20 between the operating lever 19 and the carrier plate 21.

The support ring 56 is connected to the rotary sleeve 33, for example by gluing and / or in a form-fitting manner.

The rotary sleeve 33 and the locking sleeve 51 as well as the operating element 18 are made, for example, of one or more rigid plastics and / or of metal. The rotary sleeve 33, the support ring 56, the operating element 18 and / or the locking sleeve 51 are preferably each formed in one piece. An operating button of the operating element 18 can also be made of an elastic or soft elastic plastic or rubber.

According to Fig. 11 the operating lever 19 protrudes from the pipette housing 2 through a first housing slot 60 running transversely to the longitudinal axis of the pipette housing 2 and extending over part of the circumference of the pipette housing 2 so that it can be operated from the outside. The first housing slot 60 is connected in the middle to a second housing slot 61 running downward in the longitudinal direction of the pipette housing 2.

The operating lever 19 can be displaced downward from the support ring 56 along the second housing slot 612 against the action of a spring device, sliding with the first curved slot 22 on the sector 37 of the rotating sleeve 33. After relief, the spring device automatically moves the operating lever 19 back upwards.

A sleeve-shaped fourth scanning element 62 is guided on the outside of the shaft 3. A spring device in the form of a helical spring 63 guided on the shaft is supported on the underside of the pipette housing 2 and on the upper side of the fourth scanning element 62. The fourth scanning element 62 is pressed from above against a stop element on the shaft 3 or pin 4 by the helical spring 63.

On the top of the pipette housing 2 there is an adjusting button 64 for adjusting a dosing volume. The dosing volume can be set by turning the adjusting knob 64. A counter 65 arranged underneath in the pipette housing 2 shows the respectively set dosing volume. The adjustment knob 64 and / or the counter 65 is coupled to the transmission mechanism 15. The transmission mechanism 15 is designed to change the stroke of the lifting rod 17, which is carried out by shifting the operating element 18 downwards, in accordance with the metering volume set in each case.

According to Figs. 1 to 4 a pipette tip 66, which comprises a tip cylinder 67 and a tip piston 68, is pushed onto the pin 4. The tip cylinder 67 has a tubular body 69 which has a tip opening 70 at the lower end, a collar 72 having a push-on opening 71 at the upper end and a connecting area 73 on the inner circumference of the collar 72 for clamping onto the pin 4. The connection area 73 has a complementary contour to the pin 4, which has a conical lower connection section 74 at the bottom for receiving the conical lower pin section 7, above a circumferential bead 75 for engaging in the annular groove 8 of the pin 4 and above a conical upper connection section 76 for receiving the having cylindrical upper pin portion 6. The lower connecting section 74, the bead 75 and the upper connecting section 76 form second means for positively connecting the pipette tip 66 to the pipette 1.

Below the connecting area 73, the tubular body 69 has a cylindrical piston running area 77. Below that, the tubular body 69 has a downwardly tapering tip section 78 with the shape of a hollow truncated cone. The tip portion 78 is in Fig. 4 shown and omitted in the remaining drawings for the sake of simplicity.

The tip piston 68 is inserted into the tubular body 69. This comprises a piston 79 which is guided in the piston running area 77. A piston rod 80 stands from the piston 79 and has a smaller diameter than the piston 79 has, upwards in front. The piston rod 80 has a lower rod section 81 with a larger diameter and above it an upper rod section 82 with a smaller diameter than the lower rod section 81. On the lower rod section 81, the piston rod 80 has an externally encircling clamping groove 83.

According to Fig. 12 a pipette tip family comprises five different types of pipette tips. These are pipette tips 66.1 to 66.5 with different nominal volumes of 10 µl ( Figure 12a ), 25 µl ( Figure 12b ), 100 µl ( Figure 12c ), 250 µl (Fig. D) and 1000 µl ( Figure 12e ). With all pipette tips 66.1 to 66.5 from Fig. 12 the tip piston 68.1 to 68.5 is in a position in which it is pushed as deep as possible into the tip cylinder 67.1 to 67.5.

In the case of the smaller pipette tips 66.1 to 66.3 with a nominal volume of 10, 25 and 100 µl, the tip piston 68.1 to 68.3 is pushed into the tip cylinder 67.1 to 67.3 by placing one on the tip piston 68.1 to 68.3 between piston rod 80.1 to 80.3 and piston 79.1 to 79.3 arranged disk 84.1 to 84.3 limited to a paragraph 85.1 to 85.3 in the tip cylinder 67.1 to 67.3. The two larger pipette tips 66.4, 66.5 with a nominal volume of 250 µl and 1000 µl also have a disk 84.4, 84.5 which is used to center the tip piston 68.4, 68.5 in the tip cylinder 67.4, 67.5. In the pipette tips 66.4 to 66.5, the lowest position of the tip piston 68.4 to 68.5 is (additionally) defined by placing a conical piston 79.4 to 79.5 on a conical tip section 78.4 to 78.5 at the lower end of the tip cylinder 67.3 to 67.5.

The different nominal volumes are characterized by the different heights of the collar 72.1 to 72.5 of the tip cylinder 67.1 to 67.5. The height of the collar 72.1 to 72.5 is given by the distance between the upper edge of the collar and the bead 75.1 to 75.5.

The pipette tips 66.1, 66.3 with a nominal volume of 10 μl and 100 μl form a first subfamily 86.1. In these, the upper ends of the piston rods 80.1, 80.3 in the lowest position of the tip pistons 68.1, 68.3 assume the same positions above seat areas 87.1, 87.3, which are defined by the circumferential bead 75.1, 75.3.

The pipette tips 66.2, 66.4 with a nominal volume of 25 µl and 250 µl form a second subfamily 86.2. In these, the upper ends of the piston rods 80.2, 80.4 in the lowest position of the tip pistons 68.2, 68.4 have the same position below the seat areas 87.2, 87.4, which are defined by the beads 75.2, 75.4.

The pipette tip 66.5 with a nominal volume of 1000 µl forms a third subfamily 86.3. This consists of only one family member. In this subfamily 86.3, the upper end of the piston rod 80.5 is arranged in the lowest position of the tip piston 68.5 approximately at the level of the upper edge of the seat area 87.5, which is defined by the bead 75.5.

According to Figures 13 to 15 the pipettes 1.1 to 1.3 are designed differently for pipetting with different pipette tips 66.1 to 66.5. According to Fig. 13 the pipette 1.3 is designed for pipetting with pipette tips 66.5 of the third subfamily 86.3 in the range from 100 µl to 1000 µl. According to Fig. 14 the pipette 1.1 is designed for pipetting with pipette tips 66.1, 66.3 of the first subfamily 86.1 in the range from 1 μl to 100 μl. According to Fig. 15 the pipette 1.2 is designed for pipetting with pipette tips 66.2, 66.4 of the second subfamily 86.2 in the range from 2.5 µl to 250 µl.

In the Figures 13 to 15 the tip piston 68 is each arranged in the lowest position in the tip cylinder 67. The position which the upper end of the piston rod 80 assumes in this situation is referred to in this application as the "starting position".

Figure 13a shows the pipette 1.3 for pipetting volumes up to 1000 µl with an attached pipette tip 66.5 with a nominal volume of 1000 µl. In the starting position, the upper end of the piston rod 80.5 is approximately at the same level as the upper edge of the bead 75.5 of the tip cylinder 67.5. The collar 72.5 of the pipette tip 66.5 projects upwards with respect to the bead 75.5 over a length specific to the pipette tip 66.5 with a nominal volume of 1000 μl.

According to Figure 13b the pipette tip 66.1 cannot be used with the pipette 1.3. The upper edge of the collar 72.1 presses the fourth scanning element 62 against an upper stop so that the pipette tip 66.1 cannot be pushed any further onto the pin 4. As a result, the piston rod 80.1 does not press the first scanning element 44 upward enough into the pipette 1.3, so that the operating element 18 is not shifted into the pipetting position in the center of the first housing slot 60 via the second housing slot 61. The position of the operating element 18 pivoted to the side in the first housing slot 60 prevents pipetting.

According to Figure 13c a pipette tip 66.3 cannot be used with the pipette 1.3. The upper end of the piston rod 80.3 presses the first sensing element 44 up in order to move the locking sleeve 51 into the locking position. At this point, however, the pin 4 by the bead 75.3 pressed together so that the locking sleeve 51 does not move into the locking position and thus blocks the further rotary movement of the rotating sleeve 33 and the operating element 18. As a result, the operating element 18 remains in a lateral position between the ejection position and the pipetting position within the first housing slot 60, which likewise prevents pipetting.

According to Figure 13d the pipette tip 66.2 is pushed onto the pin 4 and presses the fourth scanning element 62 against the upper stop. The bead 75.2 does not engage in the annular groove 8 and the piston rod 80.2 is too short to push the first sensing element 44 up. As a result, the operating element 18 is not shifted in the first housing slot 60 into the pipetting position centrally over the second housing slot 61. The clamping spring 30 does not engage in the clamping groove 83.2. Pipetting is not possible.

According to Figure 13e Although the pipette tip 66.4 is clamped onto the pipette 1.3, the bead 75.4 is snapped onto the groove 8 and the clamping spring 30 is snapped onto the clamping groove 88.4. The piston rod 80.4 is, however, too short to push the first scanning element 44 up so far that the operating element 18 is shifted within the first slot 60 into the pipetting position centrally above the second slot 61. The locking sleeve 51 is also not displaced into the locking position. This prevents pipetting altogether.

According to Figure 14a a pipette tip 66.1 with a nominal volume of 10 µl is attached to the pipette 1.1 for pipetting volumes of up to 100 µl. In the starting position, the upper end of the piston rod 80.1 projects upwards over a certain length with respect to the bead 75.1 of the tip cylinder 67.1. The collar 72.1 of the pipette tip 66.1 extends over a length with respect to the bead 75.1 above, which is specific for the pipette tip 66.1 with a nominal volume of 10 µl.

According to Figure 14b a pipette tip 66.3 with a nominal volume of 100 µl is attached to the pipette 1.1. In the case of the pipette tip 66.3, the upper end of the piston rod 80.3 projects by the same height above the bead 75.3 as in the case of the pipette tip 66.1. The collar 72.3 of the pipette tip 66.3 projects upwards from the bead 75.3 over a length which is specific for the pipette tip 66.3.

In Figs. 14c, d and e the pipette tips 66.2, 66.4 and 66.5 are indeed clamped onto the pipette 1.1. The piston rods 80.2, 80.4, 80.5 are too short, however, so that from the to Figure 13e pipetting is not possible for the reasons given.

According to Figure 15a a pipette tip 66.2 with a nominal volume of 25 µl is attached to the pipette 1.2 for pipetting samples with a volume of up to 250 µl. The upper end of the piston rod 80.2 of the pipette tip 66.2 is arranged a certain length below the bead 75.2. The collar 72.2 of the pipette tip 66.2 projects upward with respect to the bead 75.2 by a length which is specific for the pipette tip 66.2.

According to Figure 15b a pipette tip 66.4 with a nominal volume of 250 µl is attached to the pipette 1.2. In the starting position, the upper end of the piston rod 80.4 of the pipette tip 60.4 is arranged below the bead 75.4 by the same length as in the case of the pipette tip 66.2. The collar 72.4 of the pipette tip 66.4 projects upward by a length with respect to the bead 75.4 which is specific for the pipette tip 66.4.

According to Figures 15c, 15d, 15e does not engage the bead 75.1, 75.3, 75.5 of the pipette tips 66.1, 66.3, 66.5 into the annular groove 8, so that from the to Figure 13b pipetting is not possible for the reasons mentioned. Here, the collar 72.1 of the pipette tip 66.1 has pushed the fourth scanning element 62 against the stop.

Furthermore, the piston rods 80.1, 80.3 and 80.5 of the pipette tips 66.1, 66.3 and 66.5 are each too long, so that from the to Figure 13c pipetting is not possible.

The ejection device 31 and the blocking device 50 are components of a mechanical control device 88 coupled to the first scanning element 44, which puts the pipette 1 into a state that enables or does not enable pipetting depending on the scanned piston rod 80.

The pipette 1 can be used as follows:
According to Fig. 1 and 8th a pipette tip 66 is held on the pipette 1 in an initial state. The seat area 87 is positively connected to the pin 4 by the bead 75 engaging in the annular groove 8. The operating element 18 is in the starting position at the upper end of the second housing slot, in which the first housing slot can be rotated in both directions. The maximum angle of rotation is limited by the extent of the first and second grooves 41, 43 in the circumferential direction or of the first housing slot, depending on which extent is smaller.

The locking sleeve 51 is according to Fig. 4 arranged in the lowest position, so that it prevents unintentional detachment of the pipette tip 66 from the pin 4. A radial constriction would be required to break the positive connection of the pin 4 is required, which the locking sleeve 51 does not allow in this position. The tip piston 68 is clamped with the upper rod section 82 in the receptacle 27 of the lifting rod 17.

The fourth scanning element 62 is pressed against the upper edge of the pipette tip 66 by the pretensioned helical spring 63. The position of the fourth scanning element 62 depends on the height of the collar 72 of the attached pipette tip 66 or on the length by which the collar 72 protrudes with respect to the bead 75. The height of the collar 72 is indicative of the nominal volume of the pipette tip 66 used. The fourth scanning element 62 is coupled to a diaphragm or other range setting device on the counter 65 via a slide (not shown) or another transmission device. As a result, the counter 65 indicates the volume that can be pipetted with the respective attached pipette tip 66 during the stroke set by means of the operating element 18. Embodiments of the pipette, which has a scanning device for scanning the height of the collar of the pipette tip, as well as a family of pipette tips in which pipette tips of different types (eg with different nominal volumes) have collars of different heights, are described in the European patent application EP 18 168 763.3 described.

For the uptake of liquid, the pipette 1 with the lower end of the pipette tip 66 held on it is immersed in a liquid. Thereafter, the operating element 18 is pressed down. This movement is converted by the transmission device 15 into a lifting movement of the lifting rod 17. As a result, the tip piston 68 is displaced upward. Here, the upper rod section 82 takes the first scanning element 44 with it, so that the first guide pin 49 in the vertical part 42 of the Y-shaped first groove 41 upwards slides. Meanwhile, the locking sleeve 45 maintains its position. This is in Fig. 9 shown.

When the operating element 18 has carried out the set stroke, the pipette tip 66 is filled with a certain amount of liquid. The operating element 18 is then relieved and displaced back upwards by the spring device until it rests on the support ring 56. In order to dispense this amount of liquid, the pipette 1 with the pipette tip 66 can be aligned with another vessel. By pressing the operating element 18 downwards again, the lifting rod 17 is shifted downwards and the amount of liquid is dispensed. Here, the first guide pin 49 slides down to the junction of the first groove 41.

The stroke performed by the operating element 18 when the liquid is taken up and dispensed depends on the set amount of liquid.

The uptake and release of liquid can be carried out several times.

To eject the pipette tip 66, the operating element 18 is pivoted from the pipetting position to the right or to the left into an ejection position. This rotates the rotary sleeve 33 so that the second groove 43 displaces the second guide pin 55 and thus the locking sleeve 51 upwards until the locking sleeve 51 has released the pin 4 to such an extent that it can be deformed radially inward. For this purpose, the locking sleeve 51 is preferably pulled out of the through hole 5. Furthermore, by rotating the rotary sleeve 33, the first guide pin 49 is displaced downward in one of the two lateral sections of the lower part of the first groove 41, so that the first sensing element 44 presses against the tip piston 68, which is supported at the bottom on the tip section 78. Here, the bead 75 exerts a radial force on the pin 4, so that the latter narrowed and the positive connection between pipette tip 66 and pin 4 is dissolved. As a result, the pipette tip 66 is released from the pin 4. This is in Fig. 10 shown. The stripping of the pipette tip 66 from the pin 4 can also be assisted by the fourth scanning element 62, which is pressed by the pretensioned helical spring 63 against the upper edge of the pipette tip 66.

When the used pipette tip 66 is detached from the peg 4, a new pipette tip 66 can be connected to the peg 4. For this purpose, the pipette 1 with the pin 4 can be inserted into the plug-on opening 71 of a pipette tip 66 held ready in a carrier. In this case, the fourth scanning element 62 is displaced upwards and the helical spring 63 is pretensioned. As a result, the display of the counter 65 is set to the attached pipette tip 66. Furthermore, the upper rod section 82 presses against the underside of the first scanning element 44, so that the first guide pin 49 slides as far as the first branch point of the first groove 41. Here, the rotary sleeve 33 is rotated in the pipette housing 2 until the operating element 18 is in the pipetting position. At the same time, the second guide pin 55 slides to the lowest point in the second groove 43. As a result, the locking sleeve 51 is in the locking position of Fig. 4 relocated, in which it prevents detachment of the pipette tip 66 from the pin 4.

The connection of the tip piston 68 to the lifting rod 17 and the pipetting can take place in the manner described above.

In Fig. 16 a pipette tip 66.6 is shown, which extends from the pipette tip 66.5 of Figure 15e differs in that the piston rod 80.6 has a stop 89 below the clamping groove 83.6 at the lower end of the lower rod section 81.6. The stop 89 is formed by the top of a conical section 90 that widens upwards. Alternatively, the stop 89 is through the top of a disk or through several outwardly projecting projections distributed at the same height over the circumference of the piston rod 80.6.

The stop 89 is positioned such that the piston rod 80.6 can be pushed so far into the receptacle 27 that the clamping spring 30 engages in the clamping groove 83.6. The abutment of the stop 89 on the edge of the hole 25 prevents the piston rod 80 from being pushed into the receptacle 27 any further. The tip piston 68.6 can only be pulled out of the receptacle 27 by overcoming the clamping force of the clamping spring 30. As a result, the tip piston 68.6 is held immovably by the lifting rod 17 both upwards and downwards. This avoids pipetting errors when aspirating and dispensing the liquid.

List of reference symbols:

1

pipette

2

Pipette housing

3

shaft

4th

Cones

5

Through hole

6th

upper journal section

7th

lower journal section

8th

Ring groove

9

Clamping area

10

slot

11

slot

12th

Drive direction

13th

Transmission element

14th

Transmission rod

15th

Transmission mechanics

16

Drive element

17th

Lifting rod

18th

Control element

19th

Control lever

20th

web

21

Carrier plate

22nd

first curved slot

23

first edge recess

24

axial bore

25th

hole

26th

Longitudinal slot

27

admission

28

Spring groove

29.1

Clamping slot

29.2

Clamping slot

30th

Clamp spring

31

Discharge device

32

Curve beam

33

Rotating sleeve

34

Recess

35

Recess

36

Base

37

sector

38

sector

39

first turn

40

second curve

41

first groove

42

vertical part

43

second groove

44

first sensing element

45

upper ejector bar section

46

lower ejector bar section

47

Connecting rod section

48

second sensing element

49

first guide pin

50

Locking device

51

Locking sleeve

52

Control rod

53

second connecting rod section

54

third sensing element

55

second guide pin

56

Support ring

57

coat

58

second curved slot

59

second edge recess

60

first housing slot

61

second housing slot

62

fourth sensing element

63

Coil spring

64

Adjustment knob

65

Counter

66

Pipette tip

67

Tip cylinder

68

Top piston

69

body

70

Tip opening

71

Slip-on opening

72

collar

73

Connection area

74

lower connecting section

75

bead

76

upper connecting section

77

Piston running area

78

Lace section

79

piston

80

Piston rod

81

lower rod section

82

upper rod section

83

Clamping groove

84

disc

85

paragraph

86

Subfamily

87

sitting area

88

Control device

89

attack

90

Cone section

Claims (15)

Pipette tip family comprising pipette tips (66) of different tip types for use with pipettes (1) of different pipette types of a pipette family, • each pipette tip (66) having a tip cylinder (67) • and comprises a tip piston (68), • wherein the tip cylinder (67) has a tubular body (69) with a tip opening (70) at the lower end, an attachment opening (71) at the upper end, a seat area (87) on the inner circumference for clamping onto a clamping area (9) of a pin (4) a pipette (1) and a cylindrical piston barrel area (77) between the tip opening (70) and the seat area (87) • and the tip piston (68) a piston (79) which is sealingly guided in the piston running area (77) and an upwardly projecting piston rod (80) for clamping in an axial bore with a hole at the lower end of a lifting rod (17) of a pipette (1) having, • pipette tips (66) of the same subfamily (86) pipette tips (66) of the same tip type or pipette tips (66) of different tip types, in which the upper ends of the piston rods (80) in the respective lowest position of the tip piston (68) have the same positions with respect to the Have seating area (87) • and pipette tips (66) of different subfamilies (86) have the upper ends of the piston rods (80) in the respective lowest position of the tip piston (68) at different positions with respect to the seat area (87), • so that the pipette tips (66) of each subfamily (86) can be used for pipetting with pipettes (1) of a suitable pipette type and not with pipettes of a pipette type of the pipette family that is not adapted to them. Pipette tip family according to Claim 1, in which the pipette tips (66) of different tip types differ from one another in terms of their nominal volume. Pipette tip family according to Claim 1 or 2, in which the pipette tips (66) have a collar (72) with the push-on opening (71) at the upper end and the seat area (87) at the inner circumference of the collar (72). Pipette tip family according to claim 3, comprising at least one subfamily (86) with pipette tips (66) of different tip types, each of these pipette tips (66) having a collar (72) with a height that is characteristic of the tip type and these pipette tips (66) are formed with their seat area (87) on the inner circumference of the collar (72) to be clamped on the same clamping area (9) of a pin (4) of a pipette (1) of the same pipette type, so that their collar (72) has different heights on the pin ( 4) stand tall. Pipette tip family according to one of Claims 1 to 4, in which the nominal volumes of pipette tips (66) of different tip types of at least one subfamily (86) differ from one another by one or more powers of ten. Pipette tip family according to one of Claims 1 to 5, in which the seating area (87) of the pipette tips (66) is one on the inner circumference of the Tip cylinder (67) circumferential bead (75) or an annular groove surrounding the inner circumference of the tip cylinder (67) for snapping to an annular groove (8) surrounding the outer circumference of the pin (4) of a pipette (1) or an annular groove (8) on the outer circumference of the pin (4) of a pipette (1) has a circumferential bead of the clamping area (9). Pipette tip family according to claim 6, comprising pipette tips (66.1, 66.3) of at least one tip type of a first subfamily (86.1) with one in the respective lowest position of the tip piston (68.1, 68.3) in a first position above one on the inner circumference of the tip cylinder (67.1, 67.3) circumferential bead (75.1, 75.3) arranged upper end of the piston rod (80.1, 80.3) for use with matched pipettes (1.1) of a first pipette type, pipette tips (66.2, 66.4) of at least one further tip type of a second subfamily (86.2) with an in the respectively lowest position of the tip piston (68.2, 68.4) in a second position below an upper end of the piston rod (80.2, 80.4) arranged on the inner circumference of the tip cylinder (67.2, 67.4) encircling a bead (75.2, 75.4) for use with pipettes adapted to it (1.2) of a second type of pipette and at least one pipette tip (66.5) of at least one further type of tip third subfamily (86.3) with an upper end of the piston rod (80.5) arranged in the lowest position of the tip piston (68.5) in a third position between the first and second positions for use with matching pipettes (1.3) of a third pipette type. Pipette tip family according to one of claims 1 to 7, comprising pipette tips (66.1, 66.3) with nominal volumes of 10 µl and 100 µl of a first subfamily (86.1) for use with pipettes (1.1) of one first pipette type, pipette tips (66.2, 66.4) with a nominal volume of 25 µl and 250 µl of a second subfamily (86.2) for use with pipettes (1.2) of a second pipette type and a pipette tip (66.5) with a nominal volume of 1000 µl of a third subfamily (86.3) for use with pipettes (1.3) of a third pipette type. Pipette tip family according to one of claims 1 to 8, comprising pipette tips (66), • in which the piston rods (80) in a lower rod section (81) with a larger outer diameter a circumferential clamping groove (83) for clamping a clamping element (30) arranged on the lifting rod (17) and above it in an upper rod section (82) one opposite the lower rod section (81) have a smaller diameter, so that the upper rod section (82) cannot be clamped by the clamping element (30) of the lifting rod (17) and / or • in which the tip piston (68) below the clamping groove (83) and / or the lower rod section (81) have a stop for support on the edge of the hole (25) at the lower end of the lifting rod (17). Pipette family comprising pipettes of different pipette types for use with pipette tips of different tip types of a pipette tip family, each pipette (1) comprising the following features: • a stem-shaped pipette housing (2), • a pin (4) at the lower end of the pipette housing (2) with a clamping area (9) on the outer circumference for clamping a seat area (87) on the inner circumference of a tip cylinder (67) of a pipette tip having an attachment opening (71) at the upper end (66) and with a through hole (5) for inserting a piston rod (80) of a tip piston (68) of the pipette tip (66), • a drive device (12) comprising a lifting rod (17) with an axial bore (24) and a hole (25) at the lower end, aligned with the through bore (5) and displaceable in the longitudinal direction of the pin (4) in the pipette housing (2) for inserting the piston rod (80) and a clamping device (30) for clamping the piston rod (80) in the axial bore (24) and an operating element ( 18) for displacing a piston (79) of the tip piston (68) in the tip cylinder (67), which is sealingly guided in a piston barrel area (77) between a tip opening (70) at the lower end and the seat area (87) of the tip cylinder (67), • an elongated first scanning element (44) which can be displaced upward in the longitudinal direction of the pin (4) for scanning the upper end of an inserted into the axial bore (24) within the axial bore (24) of the lifting rod (17) when the operating element (18) is relieved Tip piston (68) of a pipette tip (66) pushed onto the pin (4) with the plug-on opening (71) and A control device (88) coupled to the first scanning element, which is designed to scan a piston rod (80) of a pipette tip (66) of a subfamily (86) of the pipette tip family matched to the pipette type of the pipette (1), in which the upper ends of the piston rods (80) in the lowest position of the tip piston (68) have the same positions with respect to the seat area (87) to put the pipette (1) in a state that enables pipetting and, when a piston rod (80) is scanned, a Pipette tip (66) of a subfamily (86) not matched to the pipette type, in which the upper ends of the piston rods (80) in the respective lowest position of the tip piston (68) have different positions with respect to the seat area (87) than the pipette tips (66) of the have subfamily (86) matched to the pipette type, to be put into a state that does not allow pipetting. Pipette family according to Claim 10, in which the control device (88) of each pipette (1) is designed (i.) When a piston rod (80) is scanned, which extends the length of the piston rod (80) of a pipette tip (66) of a pipette (1 ) has coordinated subfamily (86) to put the drive device (12) in a state that enables pipetting and to allow the pipette tip (66) to be clamped to the pin (4) and lifting rod (17) and / or (ii.) when a Piston rod (80), which is shorter than the piston rod (80) of a pipette tip (66) of a subfamily (86) matched to the pipette (1), to place the drive device (12) in a state that does not allow pipetting and / or ( iii.) when scanning a piston rod (80) which is longer than the piston rods (80) of a pipette tip (66) of a subfamily (86) matched to the pipette (1), the clamping of the pipette tip (66) to the pin (4) and / or lifting rod (17) to prevent change. A pipette family according to claim 11, wherein the control means (88) of each pipette comprises the following features: • an ejection device (31) comprising a cam support (32) rotatably mounted in the pipette housing (2), • a second scanning element (48) guided on a first curve (39) on the circumference of the curve support (32) on the elongated first Scanning element (44) which is guided in the pipette housing (2) such that it can be displaced in the longitudinal direction of the pin (4) • and an operating element (18) connected to the curve support (32), protruding from the pipette housing (2) and rotatable relative to the pipette housing (2), • wherein the ejection device (31) is designed to rotate the cam carrier (32) by turning the operating element (18) from a pipetting position to an ejection position, the first curve (39) displacing the second scanning element (48) downwards so that the elongated first sensing element (44) presses a pipette tip (66) held on the pin (4) off the pin (4) • and the ejection device (31) is formed when a piston rod (80) is scanned by the elongated first scanning element (44) which is shorter than the piston rod (80) of a pipette tip (66) of a subfamily (86) matched to the pipette (1) ) is not to turn the operating element (18) from the ejection position to the pipetting position, so that pipetting is prevented. The pipette family of claim 12, wherein the control means (88) of each pipette comprises: • the pin (4) has means for positive connection (9) with a pipette tip (66), so that a pipette tip (66) with elastic narrowing of the pin (4) and / or with elastic expansion of the pipette tip (66) before its positive Connection with the pin (4) can be pushed onto the pin (4), • a locking device (50) comprising a locking sleeve (51) arranged concentrically to the pin (4), one from the locking sleeve (51) upwards protruding control rod (52) which is displaceably guided in the direction of the pin (4) in the pipette housing (2), a third scanning element (54) protruding from the control rod (52) and a second curve (40) on the circumference of the cam carrier (32) , on which the third scanning element (54) is guided and which is designed so that when the operating element (18) is arranged in the pipetting position, the locking sleeve (51) in a locking position delimits the inside of the pin (4) and / or the pipette tip (66 ) limited on the outside so that the locking sleeve (51) prevents a pipette tip (66) connected to the pin (4) from detaching from the pin (4), • The locking sleeve (51) can be displaced upwards by turning the operating element (18) from the pipetting position to the ejection position, so that the pin (4) and / or the pipette tip (60) is at least partially released and the elongated first sensing element (44 ) pushes the pipette tip (66) from the pin (4) and when a piston rod (80) is scanned by the elongated first scanning element (44), which is longer than the piston rod (80) of a pipette tip (66) of a pipette (1) which is matched to the pipette (1) Subfamily (86), the locking sleeve (51) cannot be displaced into the locking position, so that the pipette tip (66) is prevented from jamming on the pipette (1). Pipette family according to one of Claims 10 to 13, in which the control device (88) of each pipette (1) comprises a stop which limits the pushing of pipette tips (66) onto the pin (4) so that when a pipette tip (66) is pushed on a collar (72) on the pin (4) which is longer than the collar (72) of the pipette tips (66) of a subfamily (86) matched to the pipette (1), the stop a clamping of the pipette tip (66) on the Prevents the pipette (1). Pipette system comprising a family of pipette tips according to one of Claims 1 to 9 and a family of pipettes according to one of Claims 10 to 14.

Images