ES2643155T3 - Drive system with a plurality of bellows pipettes - Google Patents

Abstract

A drive system (30) in combination with a plurality of pipettes (1) of the type comprising a dispensing part (7) and a bellows part (13); the drive system comprising: means for receiving a plurality of pipettes (36); and an actuator (32); wherein the receiving means (36) and the actuator (32) are movable in a reciprocating manner with each other to compress or decompress the bellows parts of the pipettes received in the receiving means; characterized in that the receiving means (36) comprise a plurality of pipette receiving parts (38, 40) arranged to elastically clamp around the respective pipettes to assemble the pipettes into the receiving means, in which the receiving parts of Pipettes are in the form of forks (40), in which each of said plurality of pipettes is a multi-piece pipette, having a bellows piece (5) comprising said bellows part (13) and a separate dispensing part (3) comprising said dispensing part (7), wherein the dispensing part and the bellows part comprise respective connecting parts (9, 11) that cooperate with each other to provide a separable connection between the dispensing part and the part of bellows, whereby the bellows part (5) and the dispensing part (3) of the pipette can be separated and joined together by a user to disassemble or assemble the pipette.

Description

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DESCRIPTION

Drive system with a plurality of bellows pipettes

The present invention relates to fluid handling devices for aspirating and dispensing fluids, known as pipettes. The present invention also relates to systems and methods for operating said fluid handling devices or pipettes.

Pipettes are fluid handling devices that can be used in many applications to transfer quantities of fluid from one location to another. Although pipettes can be used to aspirate and dispense gases, more commonly the liquid to be aspirated and dispensed is a liquid, and for ease of reference reference will be made to the aspiration and dispensing of liquids below. However, it will be appreciated that the invention is applicable to pipettes that can be used to manipulate any type of fluid, including gases, and where it is not explicitly indicated, any reference to liquid handling can also be applied to the handling of other fluids. , for example, gases, unless the context requires otherwise.

In general, a pipette can be operated to aspirate a fluid, for example, liquid from a location, for example, a container, and dispense it to a second location, for example, a container. In some applications, manually operated pipettes can be used, while in others, an automated system can be used. Pipettes can be used individually, or they can be part of a system of multiple pipettes. For example, in laboratory applications, automated pipette matrices can be used to simultaneously transfer quantities of, for example, liquid from one location to another, for example, under the control of a robot. The present invention is applicable to both manually and automatically operated pipettes and to pipettes that are used individually or as part of a multiple pipette system.

Typically, a pipette includes a lower dispensing part that has a dispensing tip through which fluid, for example, liquid can enter or exit the dispensing part in use, and a top part that can be actuated to cause aspiration and dispensing of the fluid, for example, liquid to and from the dispensing part in use. Depending on the configuration, for example, the volume of the dispensing part, pipettes can be used to supply a wide range of different volumes of fluid, for example, liquid as required in a range of different applications, such as clinical or clinical applications. laboratory, and can be used in conjunction with a range of different fluids, for example, liquids. Depending on the application, the pipettes can be formed from different materials, for example, plastic or glass, and can be disposable or intended for multiple uses. In some applications, a filter may be located on the dispensing tip, for example, to prevent the entrainment of fluid from a previous operation in clinical settings.

Pipettes aspirate and dispense fluids, for example, liquids as a result of a positive or negative pressure induced at or above the dispensing part of the pipette. The creation of a negative pressure will cause the fluid to be drawn into the dispensing tip of the pipette when it is submerged in the fluid, for example, liquid while the creation of a positive pressure will cause the fluid retained in the pipette to evacuate from the dispensing part once again. Many techniques are used to create positive and negative pressure in the pipette, and typically involve displacing fluid, for example, air in a region above the dispensing tip of the device. For example, in some conventional pipettes a piston can be provided to pressurize or depressurize the fluid located inside a cylinder above the dispensing tip to create a positive or negative pressure in the region above the tip that causes liquid movement. in a manner similar to a syringe. Other pipettes include bellows formations that can be actuated to pressurize or depressurize an amount of fluid located above the dispensing tip. The present invention relates to these "bellows" pipettes.

According to the invention a pipette is provided; the pipette comprising: a bellows part and a dispensing part;

wherein the pipette is a multi-piece pipette having a bellows part comprising said bellows part and a separate dispensing part comprising said dispensing part.

According to the invention, therefore, the bellows part and the dispensing part are provided with separate or discrete parts of the pipette that are joined together, instead of being integral parts of a single piece. It will be appreciated that, as used herein, the "parts" of the pipette are discrete, separate parts present in the pipette manufactured in its intended state for use. The pieces are formed separately and joined together. The present invention provides a pipette in which the bellows and the dispensing parts can be separated from each other by a user. The pieces are separated and assembled together to disassemble or assemble the pipette. In this way, the present invention can provide a pipette in which the bellows part and the dispensing part are separable and interchangeable in use, that is, by a user.

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The present invention can therefore provide a more flexible pipette than a conventional device in which the bellows part and the dispensing part are provided with different parts of the same piece. Since the bellows part and the dispensing part are provided with different parts, the pipette can be more easily adapted for use in different applications by exchanging the dispensing part or bellows part. Indeed, the bellows and dispenser parts can be mixed and combined. For example, this may allow the dispensing volume to be altered, the pipette to be customized for use with different types of fluids or, if a particular application requires the use of a dispensing part that has a filter, the dispensing part It can be exchanged for a suitable part that incorporates a filter. The use of multi-piece construction also has particular advantages to facilitate automatic pipette operation, as described in more detail below.

According to the invention, the dispensing part is the part comprising the dispensing part. The dispensing part comprises the dispensing end through which fluid in use is aspirated or dispensed, for example, liquid and can be referred to as the dispensing tip of the device. The dispensing part or tip will typically be at least partially submerged in the, for example, liquid to allow liquid aspiration when a negative pressure is created on the tip in use. The dispensing part is the part of the pipette that is intended to contain the fluid, for example, the liquid to be dispensed in use, although the level of the fluid, for example, liquid in the dispensing part will depend on the amount of fluid, for example, liquid retained in relation to the capacity of the dispensing part.

The dispensing part and the bellows part should preferably be arranged in such a way that they can be easily joined and separated from each other by a user, for example, to allow the exchange of a dispensing part or bellows part. The joint between the pieces should be such that an adequate level of fluid tension between the pieces is maintained for a particular application to allow the pipette to work. The bellows piece and the dispensing part are preferably directly connected to each other and are preferably configured to cooperate with each other to facilitate said union. The pieces may be adapted in any suitable manner to provide said joint, and one or both pieces may comprise a connection formation. Preferably, the dispensing part and / or bellows part comprise a connection part to facilitate the joining of the dispensing part and the bellows part. The connection parts cooperate with each other to provide a connection between the dispensing part and the bellows part. The connection parts may comprise end parts of the respective parts that are coupled together during the joining of the parts. The connection parts may be arranged to fit together. In some embodiments the parts are arranged so that they fit elastically together. In some embodiments, the connection parts are arranged to receive one another to provide a joint between the parts. Preferably, the dispensing part then receives the bellows part. In these embodiments, the connecting parts of the pieces overlap each other. However, it is envisioned that other forms of union can be used, and the connection parts need not overlap each other. For example, some form of end-to-end joint can be used that provides the necessary level of tension to the fluid.

It will be appreciated that the provision of dedicated cooperating connection parts on the respective bellows and dispensing parts can be advantageous, because they can be configured to conform to a standard setting, to allow the interchangeability of the bellows and the dispensing parts. Greater freedom can then be provided in the construction of the parts of the dispensing and bellows parts respectively below and above these connection parts, for example, to provide different fluid / liquid capacities or a stronger bellows action or weaker. The present invention provides a plurality of pipettes of the construction of multiple multiples according to the first aspect of the invention, in which the bellows pieces and the dispensing parts can be exchanged with each other. Therefore, a first pipette may comprise a first piece of bellows and a first dispensing piece, and a second pipette may comprise a second piece of bellows and a second dispensing piece. The first and second bellows pieces and / or the first and second dispenser parts are configured in such a way that they can be exchanged with each other, for example, to provide a pipette comprising the first bellows piece and the second dispensing part, and / or a pipette comprising the second piece of bellows and the first dispensing piece.

The dispensing part comprises a fluid receiving conduit therethrough, and is typically in the form of an open end liquid retention tube. The dispensing part has a lower end through which fluid, for example, liquid, the dispensing end, and an upper end that is connected to the bellows piece is dispensed. The fluid receiving conduit extends through the dispensing part from one end to the other so that it can cooperate with the inside of the bellows part. The dispensing part is hollow. During use, the gas can move in and out of at least the upper part of the fluid receiving conduit as a result of the positive or negative pressure created due to the action of the bellows part, causing the liquid or any fluid that is to be dispensed, so that it moves in or out of the dispensing part through the end of the dispensing part.

The shape and dimensions of the dispensing part and its fluid receiving conduit will depend on the intended application of the device, for example, the nature and amount of liquid to be aspirated or supplied, and any structural requirement. Numerous dispensing parts are known in the art, for example,

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tip constructions. Preferably, the dispensing part is generally cylindrical and, in the preferred embodiments, is tapered towards the tip. The dispensing part may be tapered along its entire length or only a part thereof. The present invention is applicable to pipettes having dispensing parts adapted to contain a wide range of liquid volumes.

The bellows piece comprises a bellows part to create a positive or negative pressure that can act on a fluid below it to cause the fluid, for example, liquid, to be aspirated or evacuated from the dispensing part of the pipette into use. The action of the bellows type pipettes is well understood. With reference to the case in which the fluid to be dispensed is a liquid, when the pipette is empty of liquid, the bellows part can be contracted and then released again with the dispensing end of the dispensing part submerged in liquid. In this way, the release of the bellows part creates a negative pressure below the bellows part, which can then cause fluid from inside the dispensing part to move up and fill it, allowing the liquid to enter the dispensing part through the end of the dispensing part as a result of the suction created. When it is desired to release liquid from the pipette, the bellows part contracts once more to create a positive pressure forcing the liquid out of the end of the dispensing part. The operation is similar when a different type of fluid is to be dispensed, for example, gas.

The bellows part may comprise any suitable type of bellows formation that can be operated to cause the fluid to move outwardly or within the bellows part to or from the dispensing part in use. In embodiments, the bellows part is configured to be axially compressible or expandable between expanded and contracted states to cause the fluid to move outwardly or into the bellows part into the dispensing part in use.

In embodiments, the bellows formation is provided by a plurality of axially spaced rings that extend around the circumference of the piece, which can be moved together or separated to contract or extend the bellows part and cause the fluid to flow. move in or out of the bellows formation. The rings extend around the entire circumference of the bellows part. Preferably, the bellows formation is an axially extending accordion formation and the bellows part is preferably a part of the bellows part that has been formed in the form of an accordion. The bellows formation can be formed in any suitable manner. Preferably, the bellows formation is defined by a plurality of circumferentially extending folds provided on the side walls of the bellows piece. The folds will be axially spaced folds, and can be directed radially inwards. Preferably, the folds are regular folds. In these embodiments, the side walls of the bellows part can define a zigzag profile in vertical cross section. The axial length and radial depth, for example, the width of the folds, can be selected as desired, depending on the volume of the bellows part required. The bellows part can then define a smaller and larger diameter that corresponds to the diameters defined at the radially innermost and outermost points of the folds.

In preferred embodiments, the bellows part comprises a part of the axial length of the bellows piece that has been corrugated with ring-shaped undulations that extend circumferentially. The walls of the bellows part may have a variable thickness in the axial direction in the region of the bellows formation to facilitate folding thereof. Preferably, the bellows formation is formed integrally in the bellows piece, for example, by a molding process.

In embodiments, the bellows formation is thus exposed in use and the bellows formations are defined on external surfaces of the bellows part, for example, on the externally extending wall or side walls that extend axially from the workpiece. bellows. In preferred embodiments, the bellows piece is provided with a fluid retention tube that is closed at one end, whose side walls define the bellows formation. The open end of the tube can then cooperate with the open end of the pipette dispensing part to provide a continuous fluid conduit.

It will be appreciated that these embodiments can provide a particularly simple arrangement, in which the bellows action can be provided by a single, for example, cylindrical part, which has been provided with suitable bellows formations, for example, through proper corrugation and without the need to provide any additional sleeve, insert or other mechanism in the bellows part. The bellows part can simply be compressed or decompressed axially, that is, expansion is allowed, to operate the pipette. Preferably, the lower part does not contain internal components. It will be appreciated that in the preferred embodiments of the invention, the entire interior volume of the bellows piece, which includes the region of the bellows part, can define a fluid retention chamber, maximizing the bellows effect that can be obtain. In this way, the bellows piece defines a unique fluid retention chamber that cooperates with the fluid retention chamber defined within the dispensing part. In preferred embodiments, the fluid receiving chamber defined within the bellows part extends over the entire width of the bellows piece in the radial direction and, thus, extends over the entire width of the pipette in the area of the bellows piece.

The bellows part, that is, the part that includes the bellows formations, can be extended over the entire length of the bellows piece, or it can be located only in a part thereof, preferably in the part

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higher. Preferably, the bellows part extends to an upper end of the bellows piece. Preferably, the bellows part ends in the closed upper end wall of the bellows piece. This may facilitate the operation of the bellows as described below. Preferably, the bellows part extends at least 35% of the axial length of the bellows piece. Preferably, a lower part of the bellows piece is free of bellows formations. In preferred embodiments, the bellows part extends no more than 50% of the length of the bellows piece. This may leave the lower parts of the bellows piece free for use in connection to the dispensing part and / or liquid retention as described below.

Preferably, the bellows part comprises an assembly part to facilitate the assembly of the bellows part to a drive system. Preferably, the assembly part is located below the bellows part and, where a connection part is provided to facilitate the connection of the bellows piece to the dispensing part, between the bellows part and the connection part. The assembly part may simply be a region of the bellows piece that is free of bellows formations and, preferably, that is not tapered, to facilitate assembly to a drive system. Preferably, the assembly part comprises an external formation, preferably a location groove, which cooperates in use with a part of pipette receiving means of the drive system. The assembly part may be a part of the bellows piece that is coupled by the receiving part of the receiving means in use. For example, the reception means of the drive system may comprise a part arranged to clamp around the assembly part of the bellows piece. In preferred embodiments, as described below, a receiving part of the drive device is a fork, preferably an elastic fork, and the assembly part is arranged to cooperate with a fork. These embodiments are particularly preferred since they can allow the pipette to be retained in place for operation only in the region of the bellows piece, leaving the dispensing part not attached to the drive means, so that it can be more Easily removed and replaced in use if required, without the need to disassemble the entire pipette.

It will be appreciated that the open end of the bellows piece cooperates with the upper end of the dispensing part, that is, the end furthest from the opening through which for example the liquid moves in or out of the dispensing part in use. In this way, the fluid can move between the bellows piece and the dispensing part. The movement of gas in this way can help transmit the positive or negative pressure formed due to the action of the bellows part on the dispensing part. However, it will be appreciated that the liquid can also be moved from the dispensing piece to the bellows piece.

In preferred embodiments, the bellows piece is deliberately configured such that when the liquid is aspirated by the pipette through the dispensing means, the liquid can enter, and preferably, intentionally enters the bellows piece in use. In contrast to conventional devices that are configured to prevent the liquid from rising above a certain level in the pipette, the pipettes of the invention are preferably configured so that the liquid can intentionally enter the bellows piece when aspirated during use. In fact, the lower part of the bellows piece is intended to provide an extension to the liquid retention chamber defined by the dispensing part. Thus, when a sufficient volume of liquid is aspirated by the pipette, the liquid can fill not only the interior volume of the dispensing part, but at least a part of the internal volume of the bellows piece. In this way, the range of liquid volume that can be retained by the pipette can be extended, since both the bellows piece and the dispensing part are involved in the liquid retention process.

To allow the bellows piece to function in this manner, preferably the bellows part of the bellows piece is provided in the upper part of the bellows piece and the bellows piece further comprises a lower part free of bellows formations which can Contain liquid in use. The lower part of the liquid retention part can be overlapped to an upper part of the dispensing part when the pipette is assembled, that is, it can comprise the connection part of the bellows part. However, preferably the liquid retention part of the bellows part comprises an upper part that is located between the bellows part and a connection part of the bellows part in use, for example, which does not overlap the dispensing part. The liquid retention part may include at least a part of the bellows part assembly part, when provided. In this way, the internal space defined in the region of the assembly part can at least partly define a part of the bellows piece that is intended to retain liquid in use. The liquid retention part may comprise a tapered part, and may comprise both a tapered and a non-tapered part. Preferably, the tapered part, if provided, is a lower part thereof.

Suitable relative volumes of the dispensing part and the bellows piece to allow the bellows piece to retain liquid can be empirically determined for different liquids to be retained. Similarly, the manner in which the bellows part can be operated, for example, the amount of compression required, can be determined empirically to cause the liquid to be drawn into the bellows part in use. In some embodiments, the volume of the bellows piece is greater than the volume of the dispensing part. The volume here refers to the interior volume.

It has been found that the following construction of the bellows piece may be advantageous and may be particularly suitable in conjunction with embodiments in which the bellows piece is intended for

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retain liquid in use. Preferably, the bellows piece is generally cylindrical. The parts of the bellows part below the bellows part, for example, the assembly part and the connection part and any other part, may be smaller in diameter than the bellows part. This can be achieved through proper tapering and / or different diameter levels. The bellows piece may include a tapered part, preferably in the region below the bellows part, and preferably below the assembly part. The taper is towards the dispensing end of the pipette. In preferred embodiments, the assembly part is not tapered. The tapered part can be extended to the lower end of the bellows piece, or only to the connection part. In some embodiments, the bellows piece comprises a first tapered part below the bellows part and a second tapered part below it, the first tapered part having a greater degree of taper than the second tapered part. The tapered first part is preferably located below the assembly part. The tapered second part may be located above the connection part, or it may comprise the connection part.

It will be appreciated that the most appropriate shape / diameter of the various parts of the bellows part will depend on the intended use of the pipette and the nature of the dispensing part with which the bellows part cooperates. Thus, in some embodiments, the bellows part may have a larger diameter than others to provide higher levels of aspiration if the application requires it. It is possible to vary the diameter of the bellows part over a wide range without changing the height of the bellows part, providing benefits in the ability to operate a plurality of different volume pipettes simultaneously, as described below.

In the embodiments in which the bellows piece is intended to retain liquid in use, preferably the bellows piece is arranged so that only the lower part of the bellows piece below the bellows part, that is, the part that has the bellows formation is involved in the retention of liquid. The bellows piece may be configured to prevent the liquid from completely entering the bellows part. However, preferably the bellows part is configured so that the liquid can enter the bellows part, but in such a way that the liquid that enters the bellows part in use is not retained in the bellows part. In this way, the liquid can only temporarily enter the bellows part of the bellows piece and the bellows part is configured to make any liquid that enters the bellows part tends to recede towards the pipette part below of the bellows part, and / or the lower part of the bellows piece below the bellows formations. In these embodiments, therefore, it is intended that the liquid can enter, and do so, initially in the bellows part. This can facilitate the full use of the liquid retention capacity of the part of the bellows part below the bellows part in use.

The ability of the liquid to enter only the bellows part initially before reopening in lower parts of the bellows part in use can be provided by an appropriate configuration of the bellows formations, for example, the depth of folds, the fold angle etc. Suitable configurations for given types and volumes can be determined empirically.

In preferred embodiments, the bellows part is configured so that the liquid that has entered the bellows part tends to be forced to leave the bellows part by axial compression of the bellows part. Thus, in these embodiments, any liquid that has not yet flowed down to the lower parts of the bellows piece when the drive occurs will be forced to leave the bellows formations and will not be trapped there. This can be achieved by the appropriate configuration of circumferentially extending folds that define the bellows formation and providing the folds with the ability to close under axial compression progressively radially inward, for example, from their radially outermost edges. .

In the preferred embodiments in which the bellows part defines a plurality of folds that extend circumferentially in the axial direction, the folds are configured to be closed by axial compression of the bellows part such that the liquid does not can enter and / or is forced out of at least a radially external part of the folds. Preferably, the folds are progressively closed in the radial direction inwards starting from the radially outermost edges. In this way, the liquid cannot move outward in the radial direction in at least the radially outermost parts of the folds, for example, the sections directed radially outward of the folds, and any liquid therein is forced to exit the folds towards the central part of the bellows piece so that it can fall back into the lower parts below the bellows part. It has been found that a construction of the folds that results in axially adjacent radially directed fold-out walls contact each other in the compression of the bellows parts may be useful in this regard. Thus, in embodiments, the bellows part defines a plurality of V-shaped folds radially directed outward in axial cross-section and the folds are configured such that the walls of the V-shaped folds enter contact with each other when the bellows part is compressed axially. In this way, the liquid is ejected from the folds and / or prevented from entering the folds when compressing the bellows part.

In accordance with a further aspect of the present invention, a pipette is provided; the pipette comprising a bellows part and a dispensing part, in which the pipette is configured so that it is intended that the liquid can enter, and preferably, enters the bellows part in use. Preferably, the bellows part is

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arranged in such a way that the liquid tends to recede down to the lower parts of the pipette and is not retained in the bellows part and / or such that any liquid entering the bellows part is expelled from the bellows part bellows when the bellows part is subjected to axial compression as described above.

These additional aspects of the invention may include any or all of the features described with respect to the first aspect of the invention. Of course, it will be appreciated that it is not necessary for the bellows part to be configured so that it can participate in the retention of liquid in all embodiments, and it may be desired in some applications to provide a bellows part that is configured to inhibit the liquid from entering the bellows piece.

It will be appreciated that in use, the bellows part will have to be actuated in order to cause aspiration and fluid supply, for example, liquid from the dispensing part. The bellows part is arranged in such a way that axial expansion is compressed or allowed to cause aspiration or supply of, for example, liquid through the dispensing part. Therefore, the bellows part can be compressed axially from a natural state without tension, for example, a length to a contracted state, for example, a length causing the fluid to be displaced from inside the bellows part towards the upper part of the dispensing part to cause, for example, liquid contained in the dispensing part to be expelled through the dispensing tip. The bellows part can then be allowed to expand axially, for example, extending once to the unstressed state to drag fluid from the dispensing part, thereby sucking liquid through the dispensing tip into the dispensing part during aspiration. . This allows the bellows part to expand can be called decompression of the bellows part. Compression may involve applying a force directly to the bellows part, or indirectly, for example, through one end of the bellows part if the bellows part does not extend to one end of the pipette. In embodiments, axial compression and decompression results in collapse and expansion of the bellows formations. Of course, the bellows part does not need to completely return to its fully extended state without tension in each drive depending on the volume of liquid to be aspirated or dispensed. All that is required is that there is a relative compression or extension of the bellows part between its initial and final states. The required amount of compression to cause aspiration or dispensing of a desired volume of a particular liquid can be determined empirically, for example, using calibration curves.

The bellows portion may be arranged such that compression (or expansion) can occur only in discrete amounts, for example, corresponding to full compression or without compression, or more preferably it can be compressible for a continuous range of quantities. In preferred embodiments, the bellows part is arranged in such a way that it will tend to expand into its expanded state without tension in the absence of an opposing contraction force. This can be achieved using suitable materials, and / or bellows configurations, for example, accordion-like folds that tend to open in the absence of any opposing force. The length of the bellows part along the axis of the bellows piece is greater in the expanded state than its contracted state. Thus, during the dispensing of, for example, liquid through the dispensing part, the length of the bellows part decreases as the bellows piece is compressed, while during the liquid aspiration its length increases. Preferably, the contraction or extension in the bellows piece results in a corresponding overall decrease or increase in the length of the pipette. This occurs when the bellows formations are preferably formed in an outer wall of the pipette.

It will be appreciated that the present invention can provide a particularly simple pipette, which can be operated by pressing or decompressing, for example, releasing the closed axial end of the bellows piece, that is, the end furthest from the dispensing end and without the need for any other drive components, for example, a pump, a piston, etc.

The operation of the bellows part to dispense or aspirate fluid, for example, liquid through the dispensing part, can be achieved manually or automatically. In the manually operated embodiments, a user can directly exert a compression force on the end of the bellows part in the same manner as with a pipette of a single bellows piece / dispensing part combined using a finger or several fingers. In other embodiments, the pipette may be assembled in a drive system to automatically operate the bellows part. It has been found that the multi-piece pipette of the present invention is particularly advantageous when used in conjunction with an automated drive system. The pipette is assembled in an automated drive system and the present invention extends to a pipette in accordance with any of the aspects or embodiments of the invention in combination with an automated drive system. The drive system comprises an actuator and means for receiving a plurality of pipettes, the receiving means and the actuator being movable with each other to compress or decompress the parts of pipette bellows received in the receiving means in use.

It is believed that such a drive system is advantageous in its own right, and from an additional aspect of the invention there is provided a drive system for a plurality of pipettes of the type comprising a bellows part; the drive system comprising: means for receiving a plurality of pipettes; and a

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actuator; wherein the receiving means and the actuator are movable with each other to compress or decompress the bellows parts of pipettes received in the receiving means in use.

The present invention according to this additional aspect may include any or all features of the other aspects of the invention insofar as they are not mutually inconsistent with it.

In this way, by an appropriate flow between the receiving means and the actuator, the present invention can provide a particularly simple way of operating a plurality of pipettes, that is, a multi pipette actuation system, increasing or decreasing the separation between the receiving means and the actuator, to compress the bellows parts of the pipettes retained in the receiving means or allow them to expand. Compression or decompression of the bellows parts may result in, for example, the liquid being distributed or aspirated through the dispensing part or parts of the pipette or the pipettes in use. It will be appreciated that compression of the bellows portion can be carried out to supply, for example, liquid contained in the pipette, or to create a negative pressure in preparation for the aspiration of liquid when liquid was not previously located in the pipette and The expansion of the bellows piece can be used to aspirate the liquid. An appropriate selection of the relative movement between the actuator and the receiving means can then be used to carry out a desired sequence of aspiration or supply of fluid to transport fluid between locations or other operations as desired.

The invention extends to the drive system in combination with at least one, and preferably a plurality of pipettes received by the receiving means. In these additional aspects of the invention, pipettes can be of any suitable form as long as they comprise a part of bellows. For example, pipettes may comprise a single piece that has a bellows part and a dispensing part. However, preferably the pipettes are multi-piece pipettes that have separate supply and bellows parts according to any of the embodiments of the first aspect of the invention described above.

It has been found that the multi-piece pipette construction of the present invention is particularly compatible with this form of actuation. It is believed that the pipette can be structurally stronger as a result of the use of multi-part construction, such that automated compression of the bellows part can proceed with the bending or bending of the pipette in a manner that could interfere with its ability to be able to reliably enter a container to which the liquid is to be supplied, or from which it will be aspirated. The construction of multiple pieces can result in a more rigid pipette than a corresponding single-piece pipette formed of the same material and thicknesses, etc. Since pipettes can more reliably discharge their contents into a container, the need to provide some form of guidance to try to ensure that fluid enters the container is avoided. Such guides are undesirable, since they are associated with an unacceptable risk of contamination by contact with liquid present outside the dispensing part of the pipette.

In these aspects and embodiments of the invention, the actuator and the receiving means are movable with each other to actuate the pipettes, that is, to result in the compression of the bellows parts, or to allow them to expand. . The flow of the actuator and the receiving means results in the application of an axial compression force on the pipettes to compress the bellows parts. The vaiven can result in a space between the actuator and the receiving means within which the bellows parts are located in use by decreasing or increasing in height, that is, an increase or decrease in the vertical separation of the actuator and the means of reception.

The vaiven may involve the movement of the receiving means or the actuator, or both, provided there is relative movement. Preferably, the actuator is movable with respect to the receiving means. Preferably, the receiving means are fixed during the vaiven and the actuator is mobile, that is, movable with vaiven with respect to them. Preferably, the vaiven occurs in a generally vertical plane.

In embodiments, the actuator is preferably mobile between the first and second positions, for example, corresponding to raised and lowered positions. The actuator can extend in a generally horizontal plane and move in a generally vertical plane during the drive. The actuator can therefore move from an upper position to a lower position to compress the bellows part or parts or vice versa from a lower position to an upper position to allow the bellows part or parts to expand or decompress. The actuator may be arranged to automatically return to the first position, for example, in which the bellows part expands, when no opposing force is exerted. This can be achieved, for example, by proper polarization with a spring.

It is not necessary for a vaiven to be made over the entire distance available in each action. It will be appreciated that the drive system can be controlled to cause a relative flow in a given amount between the actuator and the receiving means in order to dispense or aspirate a desired amount of fluid. The required amount of flow to dispense or aspirate a given amount of a particular fluid can be determined empirically and the calibration curves determined. The amounts of flow required to dispense or aspirate different amounts of fluid can be stored together with the relevant conditions, for example,

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type of fluid, volume of bellows and / or dispensing parts, etc. A control system associated with the drive system can then search for the relevant values for a particular set of conditions provided. In this way, the system can then be controlled using stored data to provide a given amount of flow for a particular set of conditions. In embodiments, the drive system is arranged in such a way that the vaiven can be carried out at discrete levels or quanta of the available distance. The system can then be programmed to perform a change over a given number of levels for relevant operations, or to search for the corresponding number of levels using stored data.

The present invention extends to an operating procedure of an automated pipette drive system in accordance with these additional aspects of the invention and, in accordance with a further aspect of the present invention, an operating procedure of an automated system is provided. of pipette drive to drive a plurality of pipettes, each of which comprises a bellows part; the drive system comprising: pipette receiving means for receiving a plurality of pipettes that are operated; and an actuator; the actuator and the pipette receiving means being movable with each other to reciprocate respectively the bellows parts or allowing the bellows parts of the pipettes to extend; the procedure comprising the drive of the actuator and the means of receiving each other in a manner that results in the compression or decompression of the bellows parts.

The present invention according to this additional aspect may include any or all features of the other aspects of the invention insofar as they are not mutually inconsistent with it.

The bellows parts can be compressed to thereby dispense the liquid contained in the dispensing parts of the dispensing parts of the pipettes in use, or to create a negative pressure in preparation for the aspiration of liquid and / or decompressed to allow the Bellows parts expand and, aspirate the liquid into the dispensing parts of the pipettes. In preferred embodiments, the method may comprise the step of determining the amount of relative flow required to dispense or aspirate a given amount of fluid, and controlling the drive system such that the actuator and the receiving means move with they live among themselves in the determined amount. The quantity can be determined by the calculation, or, for example, obtained, for example from a database or from a search table.

The timing between the actuator and the receiving means can be achieved in any suitable way. The system may comprise means of vaiven to cause the vaiven. For example, the actuator and / or receiving means can be connected to a motor for this purpose.

According to any of the embodiments of the invention, the actuator can be of any suitable type. Preferably, the actuator is an actuator element, and more preferably an actuation surface. For example, the actuator can be in the form of a bar and the drive can be carried out by a lower surface of the bar. The surface may comprise, for example, projections or holes for coupling different types of pipettes, or it may be flat. In preferred embodiments, the drive surface is provided with a drive plate. In these embodiments, the plate is preferably a vaiven plate.

The actuator is preferably arranged to couple the upper end or ends of each pipette assembled in a pipette receiving means of the system, preferably the end of a piece of pipette bellows according to the invention. The actuator can couple the end of the bellows parts at all times, or only during a part of its travel during the drive.

It will be appreciated that the same actuator is arranged to drive a plurality of pipettes. Pipettes can be arranged in a group such as a row or matrix of pipettes. The same actuator does not necessarily have to operate each pipette maintained by the receiving means, although preferably it does. In embodiments, the actuator can result in the actuation of the plurality of pipettes simultaneously. This can be achieved by assembling the pipettes so that the upper parts of the bellows parts are at the same level to be coupled to the actuator at the same time. This arrangement is particularly simple, avoiding the need to provide a pump, piston or other more complex drive system. In embodiments, the pipettes can be automatically operated by placing an actuator against the upper part of the lower parts, axially compressing the bellows formations integrally molded into the upper part or part of the pipette, without the need for additional components or internal mechanism.

According to the invention, the volume of the bellows part can be varied over a wide range by varying the diameter of the bellows part and without altering its height. This can allow the production of pipettes with a wide variety of volumes. The volume of the bellows part may affect the amount of contraction required to aspirate a given volume of fluid or, in embodiments, the amount of liquid that can be retained by the bellows part that contributes to the total capacity of the pipette.

Preferably, the receiving means are arranged to keep the pipettes in a fixed position at least

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in the direction of vaiven, and preferably in all directions, as the actuator moves with vaiven. The receiving means are configured to retain the pipettes so that they are oriented with their longitudinal axes parallel to the direction of flow, that is, perpendicular to the plane of the actuator in preferred embodiments. The axial ends of the pipettes can then be maintained in such a way that they extend in a plane parallel to the plane of the drive surface.

The reception means of the drive system may be arranged to retain the pipettes in a row, matrix or other pattern. Preferably, the receiving means comprise a plurality of pipette receiving portions, each being arranged to cooperate with one or more pipettes to assemble the pipettes to the drive system. Preferably, each receiving part is arranged to cooperate with a single pipette to assemble the pipette to the drive system. Preferably, the reception means comprise a plurality of pipette receiving parts that are located on the same vertical level. This can facilitate simultaneous operation of multiple pipettes. Preferably, the receiving means are configured to assemble a plurality of pipettes such that they are radially spaced from each other.

In preferred embodiments, as described above, each pipette comprises an assembly part that cooperates with a receiving part of the actuating device, and each receiving part of the receiving means will therefore preferably cooperate, for example, coupling a assembly part of a respective pipette. Preferably, the receiving part is coupled to a location groove of the assembly part. The assembly part is, in embodiments, located below the bellows parts. In preferred embodiments, in which the pipette is of the multi-piece construction, the receiving part of the actuating means cooperates with the bellows part of the pipette, and preferably with an assembly part provided in the bellows part of the pipette. Preferably, the reception means of the drive system are arranged to couple only the bellows part of the pipette and not the dispensing part. In these embodiments, the dispensing part is not assembled directly in the drive means, and is not supported by anything other than its attachment to the bellows part. These embodiments are advantageous since they allow the dispensing parts to be easily removed and attached to the bellows parts without the need to remove the bellows part from the drive system. In this way, the dispensing part associated with a particular bellows part can be removed therefrom and replaced, if desired, by a different dispensing part, for example, to allow dispensing of different volumes or types of liquid or to provide a dispensing part that incorporates a filter, and without interrupting the operation of a drive system path.

For example, thereby coupling the receiving parts in such a way that each one is located at the same vertical separation of the actuator at any relative position of the receiving and actuator means during the drive, the upper part of each bellows piece of the plurality of pipettes held in the receiving means will be coupled to the actuator simultaneously when the bellows pieces are of the same height. This can be ensured by providing assembly parts in each of the plurality of pipettes in a fixed position with respect to the bellows parts, that is, a fixed distance along the axis of the bellows part. In this way, each pipette can have bellows parts and assembly parts of standard heights. However, the construction of multiple parts of the pipettes can provide flexibility despite the need to provide bellows parts of the same height in these embodiments, since the diameter of the bellows part can be altered without interfering with the connection to the drive system. The ability to mix and match bellows of different volumes and dispensing parts can provide great flexibility in use.

In accordance with the invention in any of its aspects or embodiments, the receiving part must retain the pipette as required during operation, but must allow the pipette to be released when required. The receiving part may be of any suitable construction, and may simply be a hole in a plate through which the pipette is inserted, with a size properly selected to retain the pipette. In these embodiments, the receiving means may comprise a plate having a plurality of holes therein to receive and retain each of a plurality of pipettes. However, preferably the receiving part is arranged to be held around the pipette, and in particularly preferred embodiments it is in the form of a fork. Preferably, the receiving means comprise a plurality of fastening means, preferably forks, to each receive a plurality of pipettes. Preferably, in any of its forms, the receiving part is an elastic part, for example, arranged to receive the pipette by means of an elastic adjustment. For example, a fork can be arranged to snap around a pipette. This may allow the receiving part to more easily accommodate pipettes of different diameters in use, providing the ability to provide different volumes without changing the height of the bellows pieces.

In embodiments, the reception means and, for example, the reception parts such as forks, are plastic and are preferably integrally molded. For example, they can be produced by injection molding.

According to a further aspect of the invention, an actuation system is provided for a plurality of pipettes of the type having a bellows part, the system comprising: an actuator, and means for

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receiving the pipettes, in which the receiving means comprise a plurality of receiving parts arranged to elastically hold around the respective pipettes in use to assemble the pipettes into the receiving means.

According to the invention in any of its aspects or embodiments, the reception means may be arranged to allow the movement of the pipettes received therein in one or more directions, for example, perpendicular to the relative vaiven direction ( preferably the direction of movement of the actuator). This may allow the movement of the pipettes as required, for example, between sets of containers between which the liquid is to be transferred, to release the pipettes or perform other functions as required. Preferably, the receiving means are arranged to achieve said movement without substantial relative movement between the receiving means and the pipettes assembled therein (unless it is limited to the pipettes to move with the receiving means, for example by being retained in a recipient). In preferred embodiments, the reception means comprise a plurality of receiving parts for receiving pipettes, each of which is assembled on a common assembly plate, the assembly plate being movable in at least one direction. In this way, each pipette held in the receiving means can be moved simultaneously. In preferred embodiments, the receiving means are arranged to be movable in at least one direction perpendicular to the direction of flow to move the assembled pipettes therein in said direction or directions, for example one direction forward and backward and / or an address from side to side. If the direction of flow between the actuator and the receiving means is taken as the Y direction, the receiving means can then be mobile in one or both of the X and Z directions. These addresses will be in the radial direction with respect to the pipettes Preferably, the reception means are movable in a direction perpendicular to the plane in which the vaiven occurs. This may allow the receiving means to receive or release pipettes, as described below.

The movement of the receiving means, actuator and other parts of the system can be achieved under the control of a robot, a computer, for example, a workstation or any suitable control means.

The receiving means may be arranged to release the bellows parts or pieces in any way. In some preferred embodiments, the receiving means are arranged such that the pipettes can be released when the receiving means move properly with respect to the pipettes. The receiving means can then be moved with respect to the pipettes in a manner that results in the decoupling of the pipettes from the receiving means. This may be, for example, a direction of movement from side to side or forward and backward in the Z direction depending on the configuration of the receiving means. In some embodiments, the receiving means move in an orthogonal direction to the plane in which the vaiven occurs, for example, the plane in which the actuator moves during the vaiven, ie radially with respect to the pipettes to release the pipettes. For example, in preferred embodiments in which the receiving parts of the drive system are in the form of forks or other open formations, the pipettes can be released by moving the forks, for example, backwards with respect to the pipettes. This will be in the radial direction of the pipettes. Preferably, the receiving means are arranged to be movable in an orthogonal direction to the plane in which the flow occurs to release the pipettes. If the plate is taken to move in the Y direction, this may correspond to a forward and backward movement of the receiving means. It should be limited that the pipettes move with the receiving means to allow them to be disassembled from the receiving means as they move, that is, to allow relative movement between the receiving means and the pipettes. This can be achieved by locating the dispensing parts of the pipettes in suitable retention means, for example, in containers. These containers may be containers corresponding to those located below the dispensing parts when they are located in a "disposal" position. When the pipettes are released, they can be deposited in these containers.

The assembly of the pipettes in the receiving means can be achieved by moving the receiving means with respect to the pipettes to be received in a manner similar to the release of the pipettes, but using an inverse direction of movement such that the receiving means move towards the pipettes. In this way, the movement of the receiving means in a forward direction perpendicular to the plane in which the vaiven occurs can be used to assemble pipettes while the movement of the receiving means in a backward direction can be used to Release pipettes Again, pipettes can be held in an assembly standby position before being received by the receiving means. The method may comprise the step of assembling a plurality of pipettes into the pipette receiving means.

It will be appreciated that the present invention may allow the transport of liquid between containers located in the first and second positions by an appropriate movement of the pipettes between aspiration and delivery. This can be achieved by moving the pipette receiving means in an orthogonal direction to the direction of the plane in which a relative flow occurs between the actuator and the receiving means as described above. The containers may be sets of containers. For example, the containers may be liquid receiving chambers defined in trays. The cameras can be pozillos, etc., as is known in the art.

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The present invention extends the use of a drive system in accordance with the above aspects and embodiments of the invention to operate one or more pipettes, preferably a plurality of pipettes simultaneously.

The present invention extends to a drive system according to any of the additional aspects and embodiments of the invention in combination with one, or a plurality of pipettes. Preferably, the pipettes are in accordance with any of the embodiments of the first or second aspect of the invention.

The present invention extends to the drive system in combination with a plurality of containers from which the liquid from the pipettes is to be supplied, or from which the liquid is aspirated by the pipettes.

As described above, although the invention has been described with particular reference to aspirating or supplying liquids, it will be appreciated that the pipettes and the actuation system of the various aspects and embodiments of the described invention are applicable to aspiration and delivery. of any fluid, for example, gases, and are not limited to their use in combination with liquids. Any reference to the dispensation or aspiration of liquids can therefore be replaced by the more general reference to fluids without departing from the invention, unless they are mutually inconsistent with the relative channels.

According to the invention in any of its aspects or embodiments, any suitable material known in the art can be used to provide the bellows and dispensing parts of the pipette. The material must have the appropriate inherent properties and / or thickness to provide a pipette that can withstand the conditions that are expected to be in use, for example, depending on the type of liquid to be transported and the drive procedure etc. Preferably the piece is formed of plastic. Preferably, the bellows piece is formed of plastic. Preferably, the bellows piece and / or dispensing part is formed by an injection molding process. In preferred embodiments, the dispensing part is a disposable part. In these embodiments, the dispensing part is intended to be thrown away after a single use, without being washed and reused. Preferably, the bellows piece is disposable. In particularly preferred embodiments, the invention can provide a plastic pipette, that is, without parts other than plastic. This can be particularly advantageous in providing a pipette that is intended to be disposable.

The present invention is applicable to pipettes that have a wide range of volumes. By way of example only, pipettes can have a volume in the range of 0.1 ml to 15000 ml, or 5 ml to 3000 ml. These intervals are not limiting, and the expert will understand how the basic construction can be applied over a very large range of dimensions, above orders of magnitude.

It will be appreciated that when assembled, the bellows piece is located above the dispensing part, and the bellows and dispensing parts thus form the upper and lower parts of the pipette.

Preferably, the pipette is a two-piece pipette. In these embodiments, the pipette consists of the bellows piece and the dispensing part.

The present invention extends to the use of a pipette or drive system according to the invention in any of its aspects or embodiments.

When not explicitly stated, it will be appreciated that the embodiments according to any aspect of the invention may incorporate any or all of the features described with respect to other aspects of the invention unless they are inconsistent with it.

Some preferred embodiments of the invention will now be described by way of example only and with reference to the accompanying drawings, in which:

Figure 1 is a schematic perspective view showing a two-piece pipette mounted in accordance with a preferred embodiment of the invention;

Figure 2 is a schematic perspective view showing the pipette dispensing part of Figure 1 in more detail;

Figure 3 is a perspective view showing the bellows part of the pipette of Figure 1 in more detail;

Figures 4 and 5 are additional perspective views of the bellows piece shown in Figure 3 illustrating certain features in more detail;

Figure 6 is a vertical cross-sectional view taken along the axis of the bellows piece shown in Figure 4, and showing certain dimensional characteristics of an exemplary embodiment in more detail;

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Figure 7 corresponds to the view of Figure 4, but showing certain dimensional characteristics of an exemplary embodiment of the invention in more detail;

Figures 7A and B show the configuration of the folds of the embodiment of Figure 7 schematically before and after being subjected to axial compression;

Figure 8 shows the pipette according to the embodiment of Figures 1 to 7 assembled in an automated drive system according to a preferred embodiment of the invention;

Figure 9 is a perspective view schematically illustrating the manner in which the pipette is assembled in the drive system in more detail; Y

Figure 10 is a side view schematically showing the manner in which the receiving fork of the drive system cooperates with the assembly part of the bellows part of the pipette in more detail.

The construction of a pipette according to an embodiment of the invention will now be described with reference to Figures 1-7B.

Figure 1 shows a two-piece pipette 1 mounted in accordance with a first embodiment of the invention. Pipette 1 includes a dispensing part 3 and a discrete bellows piece 5 formed and joined separately.

The dispensing part 3 has the form of a conventional dispensing tip, which is generally cylindrical and tapered towards its open dispensing end 7. The dispensing part 3 is hollow and defines an inner fluid receiving chamber. The dispensing part 3 includes a dispensing end 7 through which the liquid enters or exits the interior of the dispensing part. The dispensing part also includes a connection part 9 at the end furthest from the dispensing end 7. The connection part 9 receives a corresponding connection part 11 disposed at the lower end of the bellows part 5. The respective connection parts 9 , 11 are arranged to cooperate or fit together to firmly attach the dispensing parts and bellows together. The connecting part 11 of the bellows piece is received by the connecting part 9 of the dispensing part 3. The lower end of the bellows piece 5 is indicated by the dotted lines within the overlapping part of the connection of the dispensing parts. The bellows piece 5 and the dispensing part 3 can be separated from each other and assembled as desired. The pipette defines a longitudinal axis in the direction of arrow A. The pipette has length or height along this axis. The diameter or width of the pipette extends perpendicularly to it along a horizontal section. The bellows piece can be described as being the top of the pipette, and the dispensing part, the bottom.

Both the bellows part 5 and the dispensing part 3 are formed of injection molded plastic and are intended to be disposable.

The bellows piece 5 includes at its upper end, that is, the furthest end of the dispensing part 3, a bellows part 13. The bellows part 13 is that part of the bellows part 5 which has bellows formations 15 in the form of a plurality of circumferentially extending folds provided at intervals along the axis of the device and the bellows piece 5 providing an accordion shape in its upper region.

Corrugations of the accordion shape are defined on the outer side walls of the bellows part. The bellows part also defines a closed end wall 17 against which an axial force can be applied in the direction B to compress the bellows part. The accordion formation allows compressing and decompressing the bellows part 13, that is, it allows extension once again in the direction of the arrow A in use when an axial compression force is applied thereto.

The bellows part 13, that is, the part having the bellows formation similar to accordion, does not extend along the entire bellows piece 5. Between the bellows part 13 and the connecting part 11 of the piece There are additional parts 17 and 19 of bellows that are free of any bellows type formation. The part 17 is in the form of a smooth wall section without tapering that ends in the location groove 21 and defines an assembly part that cooperates with a receiving part of a drive system to assemble the pipette to the drive system as describe in more detail below. Part 19 includes a tapered section 19a and an additional section 19b adjacent to the connection portion 11 that is not tapered or has been tapered to a lesser extent. Sections 19a and 19b do not overlap the connection part 9 of the dispensing part when attached thereto.

In accordance with certain embodiments of the invention, the liquid can not only enter the dispensing part 3, but is also intended to enter the lower part of the bellows part in the region below the bellows part 13 that is, parts 11, 17 and 19 in use. These parts of the bellows part 5 located below the bellows part 13 thus define a liquid receiving chamber, within which it is intended

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introduce liquid during use.

Figure 2 shows the dispensing part 3 in more detail.

The bellows piece 5 is shown in more detail with respect to Figures 3 to 5. These figures show the assembly and connection parts, and the parts therebetween that can receive liquid in use, in more detail.

Figure 6 is a vertical cross-sectional view taken along the axis of the bellows piece shown in Figure 4, and showing the configuration of the bellows part 13 in more detail. It will be noted that the bellows section similar to accordion is defined by a plurality of radial folds 25 directed inwardly spaced at intervals along the axis of the bellows piece. The folds 25 define a zigzag profile in vertical cross section.

In the embodiments of the invention, the bellows piece 5 is designed so that when mounted to the dispensing part in use as shown in Figure 1, the liquid aspirated into the pipette is not only intended to enter the dispensing part 3, but also at least the lower part of the bellows part below the bellows part 13. In this way, the lower part of the bellows part below the bellows part, i.e. parts marked 11, 19 and 17 provide an extension to the liquid receiving chamber defined by the dispensing part, allowing a greater volume of liquid to be accommodated. The appropriate configurations of the bellows part and dispensing parts to achieve this function can be determined empirically for given volumes or liquids. In embodiments, the volume of the bellows piece is greater than the volume of the dispensing part. This can help stimulate the liquid to enter the bellows piece in use.

While the liquid enters the bellows piece, it is not desirable that it remains in the bellows part 13, that is, the part having the formation similar to accordion 15, since this may interfere with the operation of the bellows part In use. In this way, the folds 25 defining the bellows part are configured in such a way that any liquid that enters the bellows part will not be retained there, but will tend to be pushed out of the folds and will fall back into the lower part. of the bellows piece under part 13 of the bellows. Again, the appropriate configurations to achieve this can be determined empirically, for example, by the appropriate selection of the folding angles. In some preferred embodiments, the bellows part is configured so that any liquid that is present in the bellows part when compression occurs is forced out of the bellows part into the bellows part so that may fall in the area below the bellows part.

Some dimensions of an example of a bellows piece 5 that has been found to work in this manner with reference to Figures 6 and 7 will be described. It is believed that the relative volumes of the dispensing and bellows parts and the angles of the folds they can be important to provide the capacity of the bellows piece to absorb liquid and prevent the liquid from remaining in the bellows parts. These dimensions are only exemplary, and it will be appreciated that other configurations can be selected to result in this function, for different liquids and volumes. The length dimensions labeled x, y and z respectively in Figure 7 are 27.7 mm, 12.0 mm and 7.8 mm. The diameters of the parts labeled a, b and c respectively are 7.9 mm, 7.75 mm and 7.6 mm. Thus, the length of part 19b is given by y-z, the length of part 11 by z-and the length of part 19a by x-y.

Referring to Figure 6, the diameters of parts 17 and 19a, respectively (h and k) are 11.0 mm and 12.6 mm.

The distance between the adjacent folds along the axis of the bellows part d is 3.5 mm (Figure 7). There are ten such folds, and each distance between adjacent folds is identical. The diameter defined between the radially innermost parts of each of the folds 25, marked as e in Figure 6 is 12.57 mm. The diameter f measured between the radially outermost parts of the folds 25 is 18 mm. These dimensions are the same for each of the folds. The thickness of the material in the region of the folds g (figure 6) is 0.4 mm.

The total length of the bellows piece L is 77.85 mm (Figure 6).

The lengths along the A-A axis defined by the folds 25 in their radially outermost and inner parts are respectively 0.2 mm (m) and 0.6 mm (n) (Figure 7). At the base of the bellows piece, above the assembly part, there is a region with a length of 2.5 mm (o).

Figures 7A and 7B illustrate in more detail the manner in which the folds work to prevent the liquid from being trapped in the folds when axial compression occurs. When an axial force is applied in the direction of the arrow in Figure 7C, the folds 25 are compressed axially, so that the radially outermost parts at the outer edges 26 contact each other. In this way, the folds are closed from the radially outermost point inward, forcing the liquid trapped in the fold out of the fold as indicated, and preventing the liquid from entering the fold.

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In use, the bellows piece 30 can be compressed axially to force it to reduce its length in the axial direction due to the collapse of the bellows part 13, thereby displacing the fluid in the form of trapped air within the bellows formation towards the bottom of the bellows piece. In this way, the liquid retained in the pipette is forced out of the dispensing part 3, and the bellows piece 5, if any liquid is located therein. In other words, positive pressure is created. When part 13 of the bellows piece is allowed to return to its extended configuration shown in Figure 4 from its compressed configuration, a negative pressure is created in the region above the dispensing part 3, causing the liquid to be aspirated into of the dispensing part 3 and the bellows part 5 if the volume of liquid is sufficient, when the dispensing tip is submerged in liquid.

The use of the pipette will be described with reference to Figures 1 to 7. The dispensing part and the bellows part 3, 5 of the pipette are mounted by inserting the connection part 11 of the bellows part 3 into the connection part 9 of the dispensing part 5, such that they are firmly joined together. To aspirate liquid, axial pressure is exerted on the end 17 of the bellows part 13 in the direction B, causing the bellows part similar to accordion 13 to contract in the direction of the arrow A of Figure 1, reducing in length . The tip 7 of the dispensing part 3 is submerged in liquid and the force applied to the bellows piece 5 in the axial direction is removed, allowing the bellows part 13 to expand towards the configuration shown in Figure 1. As the bellows part is expanded, a negative pressure is created and the fluid moves out of the bellows part below the bellows part and the upper part of the dispensing part, creating a suction effect, dragging liquid through tip 7 inside the distribution part 3. Depending on the volume of liquid aspirated, the liquid may also enter the bellows part area below the bellows part 13. Any liquid that temporarily enters the Bellows part 13 is returned to the bottom of the bellows part or the dispensing part by the configuration of the folds of the bellows part 13, and any remainder in the bellows formation folds is ejected when It produces the action.

In order to dispense the fluid, the bellows part 13 is compressed again in a direction of the arrows A, creating a positive pressure in the upper area of the pipette, forcing the liquid out of the dispensing tip 7.

It will be appreciated that a pipette of the two-part construction shown in Figure 1 is advantageous because the dispensing and bellows parts can be exchanged, provided they are configured to be able to connect to each other. Provided that the connection parts are compatible with each other, great flexibility is provided in the lengths and volumes of the bellows piece and the dispensing part, allowing the mixing and adaptation of different parts to provide a desired pipette to transport a type particular of liquid or volume of liquid.

While the action of the pipette, that is, the compression of the bellows part 13, can be achieved by manual pressure on the end 17 of the bellows part 13, the pipette of the present invention is particularly advantageous in the context of automatic drive Next, an automatic drive apparatus system according to an aspect of the invention will be described with respect to Figures 8 to 10.

Figure 8 is a schematic view showing the pipette assembled in the drive system 30. The drive system 30 includes a vaiven plate 32 that is movable between a first position it occupies in Figure 8 and a second lower position (not shown) in the direction of arrow C. The vaiven plate 32 therefore moves in a vertical position between the first and second positions. The vaiven plate 32 is driven against an uneven spring by a motor 34 to the lower position. The plate 32 has an elastic inequality to return to the upper position shown in Figure 8. The plate moves in the Y direction using the coordinate system shown in Figure 8.

The drive system also comprises pipette receiving means 36. The pipette receiving means comprise an assembly plate 38 extending in a vertical plane parallel to the plane in which the plate 32 is moved to which they are assembled at intervals a plurality of pipette receiving parts in the form of elastic forks 40 in the X direction. This corresponds to the radial direction of a pipette. The assembly plate 38 is connected to a motor such that it is mobile in the X and Z directions.

Each of the forks 40 is arranged to receive a single pipette and is arranged to cooperate with the assembly part 17 of a bellows piece according to the invention.

The assembly of a pipette 1 in the drive system using the receiving means 36 is illustrated in more detail in Figures 9 and 10. The lower end 44 of the fork 40 is coupled with the location groove 21 at the lower end. of the assembly part 17. When a pipette 1 is correctly assembled in the pipette receiving means, the bellows part 13 extends above the retaining fork 40, such that its upper part can be coupled with the vaiven plate 32 as plate 32 is lowered from the position shown in figure 8. In this way, the vaiven of plate 32 can cause an axial compression force to be applied and repeatedly removed from the bellows part to operate the pipette. As the plate 32 moves towards the bottom, the bellows part 13 is compressed, the accordion formation collapsing, while as the plate rises once more towards the upper position, the bellows part 13 is expand once

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more. Therefore, the drive can cause the liquid to be dispensed and aspirated from the pipette in the same manner described with respect to manual operation.

The vaiven plate can be operated by discrete levels to result in a desired travel distance to compress the bellows parts in a given amount to achieve the supply of a desired amount of fluid, or conversely fluid aspiration when the path is in the opposite direction. Suitable travel distances can be stored to provide aspiration or supply of given amounts of fluids, for different volumes of the pipette or its constituent parts. The required value can then be obtained by a control system for a given set of input conditions, and the plate can be moved through the required number of levels to provide a total required travel distance. The levels may be different, or the movement may be continuous between them.

In use, the vaiven plate 32 is driven by the motor 34 from the elevated position shown in Figure 8 to a lower position that is not shown. The plate is coupled to the upper part 17 of the bellows part 13 of a pipette 1 securely retained in the fork 40. In this way, as the sway plate moves relative to the pipette, and engages with the upper end 17 of the bellows part, the bellows part is compressed, allowing the liquid to be supplied through the distal end of the dispensing part 3. Conversely, when the vaiven plate 32 moves back to its elevated position shown in figure 8, the bellows part expands to its original unstretched state, allowing the liquid to be dragged through the dispensing part when its tip is submerged in liquid. The liquid can be kept in any suitable container located below the dispensing part 3 of the pipette, for example, in a well, etc. A plurality of containers corresponding to the positions of each of the pipettes may be provided, for example, in a tray or the like. Suitable sets of containers are known in the art.

The operation of the pipette or any number of pipettes simultaneously can be easily achieved by a simple vaiven of the plate 32 in such a way that it couples the ends of the bellows parts 13 of the bellows parts 7 and compresses or decompresses the part of bellows 13 as necessary. This avoids the need to provide a pump, or complicated piston and cylinder arrangements, as in conventional arrangements. The construction of the bellows piece is greatly simplified.

In use, the assembly plate 38 of the receiving means of the actuating means can be moved in the X or Z directions to allow the movement of pipettes between sets of containers, allowing the transfer of liquid as is known in the art. The movement can be performed under the control of a workstation or a robot, for example.

It will be appreciated that the assembly and removal of the pipettes to or from the receiving means of the actuating means can be carried out very simply in these embodiments in which the receiving parts are presented in the form of forks. These operations can be achieved by moving the receiving part in the Z direction, that is to say forward or backward on the page with respect to the pipette. For example, when it is desired to disassemble the pipette 1 from the receiving means, the pipette may be located with its dispensing part at least partially received in a container. This will limit the pipette's ability to move relative to the receiving means. When the receiving means move in the Z direction backwards on the page according to the view of Figure 8, the pipette will be removed from the fork and left in the container. Suitable containers may be associated with an elimination position. The pipette assembly can proceed in a similar manner, first locating the pipette in a container, and then moving the assembly plate of the receiving means and, therefore, the forks 40 fixed thereto in the direction Z in coupling with the assembly part 17 of the pipette.

It will be appreciated that the combination of the construction of the two-piece pipette and an automatic actuation system of the type shown in Figures 8 to 10 is particularly advantageous. It has been found that the construction of two pieces provides the pipette with greater structural rigidity and strength than would be the case if the bellows part and the dispensing part were formed integrally. This allows the pipette to better resist the action of the drive means, that is, compression by the vaiven plate, reducing the likelihood of bending or flexing when coupled with the plate in a way that can interfere with the ability to the dispensing part to be placed reliably in a container.

Since only the bellows part 5 is retained within the receiving fork 40, the dispensing part 3 is not supported, except for its connection to the bellows part 5. In this way, the dispensing parts 3 can be easily exchanged even during the course of a machine operation. The ability to change the dispensing part will allow dispensing a greater range of liquids and volumes of liquid.

In addition, the construction of the bellows part 5 in preferred embodiments, which allows the liquid to enter the lower part of the bellows piece, can provide the ability to handle larger volumes of liquid than a conventional pipette.

It will be appreciated that as long as the height of the bellows parts 13 of the bellows parts 5 which extends by

on top of the assembly part 17 and, therefore, the fork 40, can be kept constant for different from the plurality of pipettes, such that each one will be reliably coupled by the vaiven plate at the same time as move down However, the flexibility in the capacity of the pipette, and its action is still possible by virtue of the ability to vary the diameter of the bellows piece 5. The use of receiving parts in the form of forks 40 that hold around the Bellows pieces allows bellows parts of different diameters to be securely fastened.

It will be appreciated that pipettes can be used in conjunction with fluids other than liquids according to the invention, although preferred embodiments involve the use of liquids. For example, 10 high density gases can be used. Furthermore, although the drive system involves a vaiven plate, it is envisioned that any arrangement of an actuator and receiving means that are movable with each other can be used.

The volumes of the pipettes of the invention may vary over a wide range. By way of example only, the volume of dispensing / aspiration may be in the range of 0.1 ml to 15000 ml, or 5 ml to 3000 ml.

Claims (15)

5 10 fifteen twenty 25 30 35 40 Four. Five fifty 55 60 65 1. A drive system (30) in combination with a plurality of pipettes (1) of the type comprising a dispensing part (7) and a bellows part (13); the drive system comprising: means for receiving a plurality of pipettes (36); and an actuator (32); wherein the receiving means (36) and the actuator (32) are movable in the form of one another to compress or decompress the bellows parts of the pipettes received in the receiving means; characterized in that the receiving means (36) comprise a plurality of pipette receiving parts (38, 40) arranged to elastically hold around the respective pipettes to assemble the pipettes into the receiving means, in which the receiving parts of pipettes are in the form of forks (40), in which each of said plurality of pipettes is a multi-piece pipette, having a bellows piece (5) comprising said bellows part (13) and a separate dispensing part (3) comprising said dispensing part (7), wherein the dispensing part and the bellows part comprise respective connecting parts (9, 11) that cooperate with each other to provide a separable union between the dispensing part and the part of bellows, whereby the bellows part (5) and the dispensing part (3) of the pipette can be separated and gathered together by a user to disassemble or assemble the pipette. 2. The combination of claim 1, wherein the connecting parts (9, 11) of the bellows part (5) and the dispensing part (3) are arranged to elastically fit together. 3. The combination of any preceding claim, wherein the bellows portion comprises a bellows formation that is an axially extending accordion formation. 4. The combination of any preceding claim, wherein each pipette further comprises an assembly part (17) to facilitate the assembly of the pipette to said drive system (30). 5. The combination of claim 4, wherein said assembly part (17) comprises a location groove (21) cooperating with a receiving part of said pipette receiving means. 6. The combination of claims 4 or 5, wherein the bellows part comprises said assembly part to facilitate the assembly of the bellows part to said drive system, the assembly part being located below the part of bellows. 7. The combination of claim 6, wherein the assembly part is not tapered and in which the bellows part further comprises a tapered part (19) below the assembly part (17). 8. The combination of any preceding claim, wherein the bellows part comprises a bellows part comprising a bellows formation and a lower part (17, 19) below said bellows part that is free of said bellows formations bellows. 9. The combination of any preceding claim, in which the bellows piece and the dispensing part are each formed of plastic. 10. The combination of any preceding claim, wherein a bellows formation of the bellows part is provided with folds (15, 25) on the outer walls of the bellows part. 11. The combination of any preceding claim, wherein the bellows part is configured to be axially compressible and expandable between expanded and contracted states to cause the fluid to move outward or into the bellows part to or from the part dispenser in use, in which the bellows part can be compressed axially by applying a force to a closed axial end of the bellows part. 12. The combination of any preceding claim, wherein a first pipette of said plurality of pipettes comprises a first piece of bellows and a first dispensing piece, and a second pipette of said plurality of pipettes comprises a second piece of bellows and a second dispensing part, in which the first and second bellows pieces and / or the first and second dispenser parts are configured such that they can be exchanged with each other to provide a pipette comprising the first bellows piece and the second dispensing part and / or a pipette comprising the second piece of bellows and the first dispensing piece. 13. A method of using the combination of any preceding claim, the method comprising assembling the plurality of pipettes into the pipette receiving means and moving the actuator and receiving means together in a manner that results in compression and / or decompression of the bellows parts of the pipettes. 14. The method of claim 13, which comprises moving the actuator and receiving means to each other to compress the bellows parts and thus dispense the liquid contained in the dispensing parts of the pipettes, or to create a negative pressure in preparation for liquid aspiration; and / or move the receiving means and the actuator in a manner that allows the bellows parts to expand and thus aspirate liquid 5 inside the dispensing parts of the pipettes. 15. The method of claims 13 or 14, further comprising the step of moving the receiving means with respect to the pipettes in a manner that results in the decoupling of the pipettes from the receiving means for releasing the pipettes.