EP3554707A1

EP3554707A1 - Fitting a piston/cylinder unit on, and releasing one such from, a dispenser for receiving and dispensing volumes of fluid

Info

Publication number: EP3554707A1
Application number: EP18706712.9A
Authority: EP
Inventors: Jürgen Schraut; Daniel Setzer; Renate Rempt
Original assignee: Brand GmbH and Co KG
Current assignee: Brand GmbH and Co KG
Priority date: 2017-02-23
Filing date: 2018-02-20
Publication date: 2019-10-23
Anticipated expiration: 2038-02-20
Also published as: US11547992B2; CN110337332B; EP3554707B1; CN110337332A; DE202017101009U1; US20200171481A1; WO2018153830A1

Abstract

The present invention relates to a dispenser for receiving and dispensing volumes of fluid, on which a piston/cylinder unit (3), having a piston (7) and a cylinder (8), can be fitted in a releasable manner by means of a movement running at least substantially in the axial direction (A) of the dispenser (1). The dispenser (1) has a piston actuator (10) for moving the piston (7) relative to the cylinder (8). The piston actuator (10) is arranged in a movable manner in the dispenser (1) and driven by means of a drive (11). According to the invention, the dispenser (1) has a locking element (12), which is arranged in a movable manner in the dispenser (1) and driven by means of a further drive (13). The invention also relates to a system for receiving and dispensing volumes of fluid, to a method for fitting a piston/cylinder unit in a releasable manner on a dispenser, and to a method for releasing a piston/cylinder unit which has been fitted on a dispenser.

Description

Attaching and detaching a piston-cylinder unit to or from a dispenser for receiving and dispensing fluid volumes

The invention relates to a dispenser for receiving and dispensing fluid volumes according to the preamble of claim 1. The invention also relates to a system for receiving and dispensing fluid volumes according to the preamble of claim 19, a method for releasably attaching a piston-cylinder unit to a dispenser according to claim 20 and a method for releasing a piston-cylinder device attached to a dispenser. Unit according to claim 27.

Task of systems of the type in question is to receive a fluid volume from a container and then deliver it to another or more other container. Such systems are used in particular for the repeated dispensing, titration or pipetting of liquids.

Such systems comprise a dispenser and a piston-cylinder unit designed as a replacement part, which can be detachably attached to the dispenser, in particular can be inserted or inserted into the dispenser. After one or more dispensing operations, the piston-cylinder unit can be released from the dispenser. Subsequently, another, in particular different piston-cylinder unit can be attached to the dispenser.

Such systems can be designed as manual or motor-operated handsets, to whose dispenser exactly one piston-cylinder unit can be attached. There are also systems on the dispenser at the same time a plurality of piston-cylinder units are mounted, such as. B. in a pipetting machine. Piston-cylinder units of the type in question can z. B. be designed as displacement units with attachable pipettes or tips (Tips) or as syringes. They each have a cylinder, in particular with a straight hollow cylinder with a substantially circular cross-section and a perpendicular to the axial direction, and a displaceable in the cylinder in the axial direction piston. Piston-cylinder units have different sized cross sections and / or lengths depending on the type. To identify the respective type, they may have geometrically different information carrier sections. Depending on the type, by displacing the piston in the cylinder, fluid volumes of different sizes can be absorbed in the cylinder or in the tip attached thereto and released therefrom. When moving the piston in the cylinder is a substantially linear movement in the axial direction of the cylinder.

It is essential for the present invention that the piston-cylinder units can be attached to the dispenser by means of a movement running at least substantially in the axial direction of the dispenser. This allows a simple, user-friendly, ergonomically advantageous and less error-prone operation of the corresponding system. The term "dispenser axial direction" refers to an alignment coincident with or parallel to the longitudinal axis of the dispenser.

In the focus of the present invention are piston-cylinder units, which operate on the Direktverdrängungsprinzip, and motor-driven, electronic multi-dispensers. In such dispensers, the actuation of one or more keys initiates a pick-up or dispensing mechanism. The piston of a piston-cylinder unit attached to the dispenser is moved by means of a motor which controls volume delivery by a microprocessor. The piston seals the inner wall of the cylinder of the piston-cylinder unit from sealing, so that exactly reproducible volume results can be achieved.

For the systems relevant here, attaching a piston-cylinder unit to the dispenser and releasing this piston-cylinder unit from the dispenser are central aspects of the use of the dispenser. Another aspect is piston-cylinder units with information carrier sections and dispenser with a detection device for automatically identifying the type of am Dispenser mounted piston-cylinder unit based on the information carrier sections. The dispensing of fluid volumes may then be controlled based on the identified type. From practice, a dispenser for receiving and dispensing fluid volumes is known, to which a piston-cylinder unit with a piston and a cylinder by means of at least substantially extending in the axial direction of the dispenser movement is detachably attachable. The known dispenser has a piston actuator for moving the piston relative to the cylinder. The piston actuator is movably disposed in the dispenser and driven by an electric motor. It is therefore a motorized, electronic dispenser.

The known dispenser has a housing and a stop element and is designed so that when attaching the piston-cylinder unit to the dispenser, a mounting portion of the cylinder can be brought into contact with the stop element. The attachment portion of the cylinder is formed by a flange, so an annular broadening of the cylinder at one end of the cylinder. The known dispenser also has a first attachment means for fixing the cylinder to the dispenser. The first fastening device has two Zylindergreifhebel and is movable in a fixing position in which the first fastening means blocks a relative movement between the cylinder and the housing in the axial direction.

The known dispenser also has a second attachment means for fixing the piston to the dispenser. The second attachment means has two piston gripping levers and is movable to a fixing position in which the piston is releasably connected to the piston actuator such that the piston is movable relative to the cylinder for receiving and / or dispensing fluid volumes by means of the piston actuator. When moving the piston-cylinder unit in the direction of the stop member relative to the housing of the dispenser, the first attachment means of the dispenser from the flange of the cylinder is moved out of the fixing position, so that the cylinder is further on the stop member to be moved. The cylinder gripping levers of the first fastening device are pressed radially outwards by the flange of the cylinder. If the flange of the cylinder comes into contact with the stop element of the dispenser, the first fastening device of the dispenser, in particular with its Zylindergreifhebeln, engages behind the flange of the cylinder. Thus, the cylinder is held in a form-fitting manner on the dispenser in the axial direction.

When moving the piston-cylinder unit in the direction of the stop element relative to the housing of the dispenser also the second fastening device is moved by a flange of the piston from the fixing position, so that the piston is further movable into the dispenser. The piston gripping levers of the second fastening device are pressed radially outwards by the flange of the piston. If the piston has been moved far enough into the dispenser, the second attachment device of the dispenser, in particular with its piston gripping levers, engages behind the flange of the piston. Thus, the piston is held in the axial direction positively on the dispenser. The piston gripping levers are coupled in terms of movement with the piston actuator. Accordingly, after the engagement of the flange of the piston, the piston for receiving and / or discharging fluid volumes can be moved relative to the cylinder by means of the piston actuator.

To release the piston-cylinder unit from the known dispenser, the first and second fastening means are manually operated such that the Zylindergreifhebel and the piston gripping levers are pressed radially outward until the cylinder and the piston are no longer held in a form-fitting manner on the dispenser. Subsequently, the piston-cylinder unit can be separated from the dispenser. An object of the present invention is the known dispenser or the known system or the known method for releasably attaching the piston-cylinder unit to the known dispenser or the known method for releasing a mounted on the dispenser piston-cylinder unit in terms the handling and / or stability in mounting and / or releasing the piston-cylinder unit and / or to improve the accuracy in recording and dispensing fluid volumes and / or in structure, reliability and / or durability. According to a first aspect of the invention, the above-described task is solved by the dispenser according to claim 1. Preferred embodiments of this aspect of the invention are the subject of the relevant subclaims. It goes without saying that embodiments, embodiments, advantages and the like, which are given below for the purpose of avoiding repetition only as an aspect of the invention, apply correspondingly in relation to the other aspects of the invention. Having said that, the present invention will be described in more detail below.

The basis of the first aspect of the invention is a dispenser for receiving and dispensing fluid volumes, to which a piston-cylinder unit with a piston and a cylinder can be detachably attached by means of a movement extending at least substantially in the axial direction of the dispenser. The dispenser has a piston actuator for moving the piston relative to the cylinder. The piston actuator is movably disposed in the dispenser and driven by a drive.

According to the invention, the dispenser has a locking element, which is movably arranged in the dispenser and driven by means of a drive. The drive of the locking element is separate from the drive of the piston actuator. Preferably, the locking element is arranged to be movable in the axial direction and movable in different positions. By moving the locking element further, explained below elements or devices of the dispenser are movable. The other elements or devices are not necessarily moved by the locking element itself. In any case, a movement of the locking element is a cause for the movement of the further elements or devices. For example, moving the locking element may cause a previously motion-blocked element to be moved with or after moving the locking element, such as moving that element e.g. B. can be effected by the spring force of a spring element. However, it is preferred if the locking element itself moves a further element or another device by its movement. It is advantageous that the elements or devices do not have to be moved manually, but are automatically moved at the behest of a user and / or a control device of the dispenser. This allows a comfortable handling of the dispenser. Preferably, the drive of the locking element is an electric stepping motor. Advantageously, the locking element is driven by means of its drive via a self-locking gear.

In a preferred embodiment, the dispenser has a housing, a stop element and a first fastening device for fixing the cylinder to the dispenser. The stop element is movable at least substantially in the axial direction relative to the housing and can be pressed relative to the housing at least partially in the attachment direction. This allows further movement of the cylinder in the mounting direction relative to the housing after the attachment portion of the cylinder bears against the stop element. Thus, an overpressure of the cylinder when mounting the piston-cylinder unit is possible. The dispenser is designed so that when attaching the piston-cylinder unit on the dispenser, a mounting portion of the cylinder can be brought into contact with the stop element. The first fastening device is movable into a fixing position, in which the first fastening device blocks a relative movement between the cylinder and the housing counter to the mounting direction.

In this embodiment, the locking element is movable into a locking position in which the locking element blocks a relative movement between the stop element and the housing in the mounting direction. Thus, the stopper element is lockable. A relative movement between the stop element and the housing in the axial direction is blocked by the locking element on the one hand and by the first fastening device on the other hand, that is not possible. In this state, when the piston is displaced in the cylinder in the mounting direction, in particular when picking up a viscous or highly viscous liquid, the fastening section prevents the stop element from being moved in the mounting direction in such a way that the cylinder slips or warp, causing the desired position to be absorbed Fluid volume deviates from the actually recorded fluid volume. This leads to an increase in accuracy when receiving and dispensing fluid volumes.

In particular, in the locking position of the locking element, the fastening portion of the cylinder between the first fastening device and the stop element is clamped such that a relative movement between the cylinder and the housing in the axial direction, and optionally in the radial direction and / or circumferential direction is blocked.

Preferably, the dispenser has means for mechanical, electronic, inductive and / or optical detection of the attachment of a piston-cylinder unit on the dispenser. This detection allows the triggering of further steps, eg. B. moving the locking element. For this purpose, the dispenser can have an optical, electronic, mechanical, magnetoresistive and / or inductive sensor device by means of which the movement of the stop element in the axial direction can be detected. The sensor device can, for. B. a light barrier with a light beam source and a sensor for detecting light rays of the light beam source, wherein the light barrier is arranged so that a movement of the stop element in the axial direction of the light barrier is detectable.

It has proved to be advantageous if the dispenser has a rear part, which exerts a restoring force on the stop element at least substantially in the axial direction against the mounting direction. If the attachment portion of the cylinder abuts on the stop element and the locking element is not in its locking position, the movement of the cylinder in the mounting direction relative to the housing must be carried out against the restoring force of the back device. As a result, tolerances of the stop element of the dispenser or the attachment portion of the cylinder are compensated and damage or wear and tear of the dispenser or cylinder avoided or at least reduced.

Preferably, the stop element is pivotally mounted or tiltably mounted on the dispenser, in particular at exactly one bearing. The pivoting or tilting axis may be oriented so that it is perpendicular and skewed to the longitudinal axis of the dispenser. It is preferred if the rear part device is arranged diametrically opposite the bearing of the stop element in the radial direction.

In a preferred embodiment, the stop element runs around in the circumferential direction and / or has a passage for the piston.

Advantageously, the rear subassembly has a spring element, in particular exactly one spring element, whose spring force as the restoring force of Returning device acts on the stop element. This allows a simple, robust, reliable and cost-effective implementation of the rear part.

In addition, it can be provided that the rear part device has a bolt which rotates around the spring element. The bolt and / or the spring element can be supported against the housing of the dispenser. The stop element may be arranged on the bolt so that it is guided along the bolt during movement of the stop element. It is preferred if the dispenser and its rear part device are designed such that a piston-cylinder unit attached to the dispenser can be separated from the dispenser by means of the rear part device. The rear part device thus facilitates an automatic separation or ejection of the piston-cylinder unit from the dispenser, after the first fastening device has been moved from its fixing position into a release parting, in which a relative movement between the cylinder and the housing against the mounting direction is executable. Incidentally, the dispenser is designed in such a way that in the release division of the first fastening device, the piston-cylinder unit can be disconnected and / or thrown off the dispenser unhindered.

In a further preferred embodiment, the dispenser has a housing and a first fastening device for fixing the cylinder to the dispenser. The first fastening device is movable into a fixing position, in which the first fastening device blocks a relative movement between the cylinder and the housing counter to the mounting direction.

In this embodiment, the first fastening device of the dispenser by moving the locking element, in particular in the axial direction, from its fixing position into a release pitch movable in which a relative movement between the cylinder and the housing against the mounting direction is executable. In the release division of the locking element, the mobility of the stop element is thus unaffected by the locking element. The dispenser according to the invention allows easy handling, in particular a comfortable release and / or separation of a piston-cylinder unit from the dispenser. Preferably, the first attachment means comprises at least two pivotally mounted Zylindergreifhebel, which can engage behind the attachment portion of the cylinder in the fixing position of the first fastening means. In a further preferred embodiment, the dispenser has a second fastening device for fixing the piston to the dispenser. The second attachment means is movable to a fixation position in which the piston is releasably connected to a piston actuator of the dispenser such that the piston is movable relative to the cylinder for receiving and / or dispensing fluid volumes via the piston actuator. For this purpose, the second fastening device may have at least two pivotally mounted piston gripping levers.

In this embodiment, the second fastening device is movable by moving the locking element from its fixing position into a release position and vice versa, wherein the piston is not connected to the piston actuator in the release position of the second fastening device.

The second fastening device is preferably coupled in terms of movement to the piston actuator and, in its fixing position over the entire path that it can perform when the piston actuator moves, can be guided by the locking element such that it remains in its fixing position.

The second fastening device preferably has two pivotally mounted piston gripping levers with cutting rollers, wherein the piston can be gripped by means of the piston gripping lever when the second fastening device moves into its fixing position. In this case, each piston gripping lever having an actuating head, by means of which the respective piston gripping lever is pivotable. Each actuator is at Move the Verhegelungselements and / or the piston actuator guided on a guide contour of the locking element. Advantageously, the extension of the guide contour in the axial direction is greater than the stroke that can be executed by the piston actuator. This prevents a loosening of the second fastening device, in particular by turning the piston-cylinder unit.

In a further preferred embodiment, the dispenser has a detection device for automatically identifying the type of a piston-cylinder unit attached to the dispenser. The detection device has a radial information reader, by means of which information of a radially oriented information carrier section of the piston-cylinder unit can be detected. Alternatively or additionally, the detection device has an axial information reader, by means of which information of an axially aligned information carrier section of the piston-cylinder unit can be detected.

In this embodiment, at least a part of the radial information reader and / or at least a part of the axial information reader is / are movable by moving the locking element.

Preferably, by moving the locking member at least a portion of the radial information reader in a radially extending recess on a piston head of the piston-cylinder unit in the radial direction and / or at least a portion of the Axialinformationslesers in an axially extending recess, in particular groove, in one End face of a piston head of the piston-cylinder unit inserted in the axial direction.

In particular, the axial information reader has a detection element which is at least partially insertable into the axially aligned recess in the axial direction. The dispenser has means by which the depth of the recess can be determined. The depth of the recess at least partially specifies the type of piston-cylinder unit. The term "type" z. B. a purpose, a state and / or a property of the piston-cylinder unit, such as. B. the maximum recordable and / or deliverable fluid volume.

The expression "axially aligned recess" is to be understood as meaning that this recess can be accessed in the axial direction of the piston-cylinder unit and / or its information can be detected in the axial direction of the piston-cylinder unit Direction of the piston-cylinder unit, a geometric extent, by means of which the detectable information of the axially aligned recess is encoded .. In addition, the axially aligned recess has a geometric extension in the radial direction of the piston-cylinder unit and in the circumferential direction of the piston-cylinder unit ,

The term "groove" is to be understood that the recess extending in the axial direction of the piston-cylinder unit in the radial direction of the piston-cylinder unit is not completely surrounded by piston material, but is partially open in the radial direction, preferably along the entire depth Such a configuration facilitates cleaning of the recess and offers a simple means of control Preferably, the detection element is tappet-like and / or pin-shaped and / or spring-loaded, in particular resiliently biased against the mounting direction of the piston-cylinder unit As soon as the locking element stops blocking the detection element, the spring-loaded detection element is moved towards the piston and finally into the axial direction saving the piston.

Preferably, the piston actuator to the piston, in particular a piston head of the piston, to be movable until a stop of the piston actuator abuts an end face of the piston. This movement, also referred to as block travel, serves to detect a piston-side reference point. The piston side In particular, the reference point marks the starting point of a determination of the depth of the axially aligned recess of the piston.

The locking element is preferably driven by means of a first motor and / or the piston actuator is driven by means of a second motor. In particular, the first motor has a lower rated output power than the second motor.

Preferably, the dispenser according to the invention is a completely autonomous, hand-durable device that combines all components regardless of location in a housing. These include, as usual, a transmission device that converts the rotational movement of the drive into a longitudinal movement of the piston actuator, electronics and a power supply. According to a second aspect of the invention, the above-described problem is solved by a system for receiving and dispensing fluid volumes according to claim 19.

The system according to the second aspect of the invention comprises a designed as a replacement part piston-cylinder unit and a dispenser as described above. The piston-cylinder unit is releasably attachable to the dispenser by means of a movement extending at least substantially in the axial direction and has a piston and a cylinder with a fastening section.

Another aspect relates to a method for releasably attaching a piston-cylinder unit to a dispenser. The piston-cylinder unit has a piston and a cylinder with a mounting portion. The dispenser has a housing, a stop element, a first attachment device for fixing the cylinder to the dispenser and a locking element. In particular, the dispenser is designed as described above. The method comprises the following method steps: a) application of the fastening section of the cylinder of the piston-cylinder unit to the stop element of the dispenser by means of a movement extending at least substantially in the axial direction of the dispenser, b) moving the first fastening device of the dispenser into a fixing position, whereby the cylinder of the piston-cylinder unit is fixed to the dispenser by means of the first fastening device of the dispenser, so that a relative movement between the cylinder of the piston-cylinder unit and the housing of the dispenser is blocked against the mounting direction and optionally in the radial direction, and

c) moving the locking element by means of a drive.

In step a) it can be provided that the piston is moved through a passage of the stop element. In order not to hinder over-pressure of the piston-cylinder unit, a piston actuator of the dispenser can be moved into a release position before step a).

Preferably, in step b), the first fastening device engages in the fixing position, the fastening portion of the cylinder by means of at least two pivotally mounted Zylindergreifhebel.

Preferably, the dispenser has detection means for automatically identifying the type of piston-cylinder unit mounted on the dispenser. The detection device has a radial information reader, by means of which information of a radially oriented information carrier section of the piston-cylinder unit can be detected. Alternatively or additionally, the detection device has an axial information reader, by means of which information of an axially aligned information carrier section of the piston-cylinder unit can be detected. In terms of method, it can now be provided that, in step c), by moving the locking element, at least part of the radial information reader is inserted into a radially aligned recess on a piston head of the piston-cylinder unit in the radial direction and / or at least one Part of the Axialinformationslesers in an axially aligned recess, in particular groove, is introduced in an end face of a piston head of the piston-cylinder unit in the axial direction / are. Preferably, movement of the stop element in the attachment direction is detected mechanically, electronically, inductively and / or optically, preferably by means of a light barrier.

In a preferred embodiment of the method, in step c), the locking element of the dispenser is moved, preferably in the axial direction, into a locking position in which a relative movement between the stop element and the housing in the attachment direction is blocked. This step can be performed by the dispenser automatically after detecting a movement of the stop member in the mounting direction. In the locking position of the locking member, the fixing portion of the cylinder is clamped between the first fastening means and the stopper member, so that relative movement between the cylinder and the housing in the axial direction, and optionally in the radial direction and / or the circumferential direction, is blocked. Thus, the cylinder is positively held in the axial direction on the dispenser - between the stop element and the fastening device.

It can be provided that a second fastening device of the dispenser for fixing the piston to the dispenser is moved by moving the locking element into a fixing position, in which the piston is detachably connected to a piston actuator of the dispenser in such a way that the piston absorbs and / or discharges of fluid volumes by means of the piston actuator relative to the cylinder is movable. Advantageously, the locking element is moved by means of a first motor and / or the piston actuator by means of a second motor. The movements can be triggered by a user or automatically by the dispenser. For receiving or dispensing a fluid volume, a relative movement between the piston and the cylinder can be generated by means of the piston actuator. In this case, the distance traveled by the piston relative to the housing of the dispenser can be determined incrementally and / or the absolute path position of a position element of the dispenser, which is coupled in terms of movement with the piston actuator, can be detected.

In a preferred embodiment of the method, a piston side reference point is detected by moving the piston actuator of the dispenser towards the piston until a stop of the piston actuator abuts an end face of the piston. In this case, the path traveled by the piston actuator can be determined, in particular by means of a device for incremental displacement measurement.

Preferably, a detection element of the dispenser is at least partially inserted into an axially aligned recess in an end face of the piston in the axial direction and determines the depth of this recess. The determined depth value can be used to identify the type of piston-cylinder unit.

Another aspect relates to a method for releasing a piston-cylinder unit attached to a dispenser. The piston-cylinder unit has a piston and a cylinder. The dispenser has a housing, a first fastening device for fixing the cylinder to the dispenser and a locking element. In particular, the dispenser is designed as described above.

The method comprises the following method steps:

Moving the locking element by means of a drive,

Moving the first fastening device from a fixing position, in which the first fastening device blocks a relative movement between the cylinder and the housing against the mounting direction, into one

Release position in which a relative movement between the cylinder and the housing against the mounting direction is executable and - Moving the cylinder relative to the housing against the mounting direction.

Preferably, by moving the locking element, a second fastening device of the dispenser is moved from a fixing position, in which the piston is releasably connected to a piston actuator of the dispenser such that the piston is movable relative to the cylinder for receiving and / or dispensing fluid volumes by means of the piston actuator, is moved to a release position in which the piston is not connected to the piston actuator. Preferably, the piston-cylinder unit is separated from the dispenser by the restoring force of a rear part of the dispenser on a stop element of the dispenser.

The invention will be explained in more detail below with reference to the description of preferred embodiments, in part with reference to the drawings. The features described above and / or disclosed in the claims and / or in the following description may, if necessary, be combined with one another but also be implemented independently of one another, even if this is not expressly described in detail.

In the drawing shows

Fig. 1 shows a schematic perspective view of a preferred

Embodiment of a dispenser according to the invention,

Fig. 2 shows schematically in a perspective view a preferred

Embodiment of a system according to the invention with the dispenser of FIG. 1 and a piston-cylinder unit in an initial state, Fig. 3 shows schematically in a perspective view a part of the dispenser of Fig. 1, wherein a simplified representation was omitted with omitting parts of the dispenser, Fig. 4 schematically shows a vertical longitudinal section through the dispenser

3,

Fig. 5 shows schematically a horizontal longitudinal section through the system

2 in a first state, wherein a simplified representation was chosen with omission of parts of the dispenser,

Fig. 6 schematically shows a horizontal longitudinal section through the system

FIG. 7 is a vertical longitudinal section through the system of FIG.

2 in a third state,

Fig. 8 schematically shows a vertical longitudinal section through the system of FIG.

2 in a fourth state,

Fig. 9 schematically shows a horizontal longitudinal section through the system

2 in a fifth state,

10 shows schematically a vertical longitudinal section through the system of FIG.

2 in a sixth state,

Fig. 1 1 schematically a horizontal longitudinal section through the system

12 in a seventh state, FIG. 12 is a schematic perspective view of the system of FIG. 5 in the third state, FIG. Fig. 13 schematically shows a perspective view of the system of Figure 5 in the fifth state, wherein the system is shown partially in section, and

Fig. 14 shows schematically in a perspective view the system of Fig. 5 in the sixth state, wherein the system is shown partially in section.

Fig. 1 shows schematically in a perspective view a preferred embodiment of a dispenser 1 according to the invention for receiving and dispensing fluid volumes. The dispenser 1 has a housing 2, an axial direction A and a radial direction R.

At the dispenser 1, a piston-cylinder unit 3 is releasably attachable by means of a movement extending at least substantially in the axial direction A of the dispenser 1. For this purpose, the dispenser 1 on an underside 4 on an opening 5 for receiving a portion of the piston-cylinder unit 3.

The term "attachment direction" designates a direction running at least substantially in the axial direction A of the dispenser 1 toward the opening 5 of the dispenser 1, that is to say from right to left in FIG. 1. The attachment direction F is indicated by an arrow in FIG.

Fig. 2 shows schematically in a perspective view the dispenser 1 of Fig. 1 and a piston-cylinder unit 3 as parts of a preferred embodiment of a system 6 according to the invention for receiving and dispensing fluid volumes.

The piston-cylinder unit 3 is designed as a replacement part. It may be in the form of a syringe and be present in different sizes with different receiving volume. It has a sealed piston 7, which in a cylinder 8 of the piston-cylinder unit 3 for the purpose of receiving and discharging or ejecting or to be pipetted or dosing liquid is movable. The cylinder 8 has a mounting portion 9, which is here formed by a flange, that is, an annular broadening of the cylinder 8, at that end of the cylinder 8, from which the piston 7 protrudes from the cylinder 8. The flange 9 has a U-shaped profile in longitudinal section, so resembles a collar.

FIGS. 3 and 4 show, in a different view, a part of the dispenser 1 from FIG. 1. FIGS. 5 to 14 show different views of the system 6 of FIG. 2 in different states. In FIGS. 3 to 14, the dispenser 1 is shown only partially. Namely, Figs. 3 to 14 are limited to the illustration of those components which are required to explain the present invention, respectively. In the vertical longitudinal sections, the system of FIG. 2 is cut (in a state other than the initial state) along a plane that intersects the plane of the drawing in a vertical straight line. In the horizontal longitudinal sections, the system of FIG. 2 is cut (in a state other than the initial state) along a plane which intersects the plane of the drawing in a horizontal straight line. The dispenser 1 has a piston actuator 10 for moving the piston 7 relative to the cylinder 8. The piston actuator 10 is movably disposed in the dispenser 1 and by means of a first drive 1 1, namely a motor 1 1, driven.

The dispenser has a locking element 12 which is arranged movably in the dispenser 1 and driven by means of a second drive 13. The second drive 13 of the locking element 12 is separate from the first drive 1 1 of the piston actuator 10th

In the illustrated and preferred embodiment, the second drive 13 of the locking element 12 is an electric stepper motor. The locking element 12 is driven by means of its drive 13 via a self-locking gear. The motor 13 has a smaller rated output here as the engine 1 1 of the piston actuator 10. This allows a more cost-effective implementation.

In the illustrated and preferred embodiment, the locking element 12 is arranged to be movable in the axial direction A and movable in different positions. Fig. 3 shows the locking element 12 in its basic position.

In the preferred embodiment shown here, the dispenser 1 has a stop element 14 with a passage 15 for the piston 7 and a first attachment device 16 for fixing the cylinder 8 to the dispenser 1. The stop element 14 is at least substantially in the axial direction A relative to the housing 2 movable and relative to the housing 2 at least partially in the attachment direction F can be pressed.

The dispenser 1 is here designed so that when attaching the piston-cylinder unit 3 on the dispenser 1 of the mounting portion 9 of the cylinder 8, and that a contact surface of this mounting portion 9, in abutment with the stop element 14 can be brought.

The first fastening device 16 is movable into a fixing position, in which the first fastening device 16 blocks a relative movement between the cylinder 8 and the housing 2 against the mounting direction F. The locking element 12 is in this case movable into a locking position in which the locking element 12 blocks a relative movement between the stop element 14 and the housing 2 in the mounting direction F. Thus, the stop element 14 is lockable. In this state, a relative movement of the cylinder 8 in the axial direction A by the locking element 12 on the one hand (in mounting direction F) and by the first fastening means 16 on the other hand (against the mounting direction F) is blocked In the locking position of the locking member 12, the fixing portion 9 of the cylinder 8 between the first fastening means 16 and the stopper member 14 is clamped such that a relative movement between the cylinder 8 and the housing 2 in the axial direction A and in the radial direction R and is blocked in the circumferential direction. Thus, the cylinder 8 in the axial direction A is positively held on the dispenser 1 - between the stop element 14 and the fastening device 16 -.

In the illustrated and preferred embodiment, the stop member 14 is pivotally mounted on the dispenser 1, to a bearing 17. The pivot axis is aligned so that it is perpendicular to the longitudinal axis of the dispenser 1. Taking the contact surface of the mounting portion 9 of the cylinder 8 as an imaginary circular ring, then the pivot axis passes as a passant radially outside of the annulus, parallel to the annulus and mounting direction F above the annulus and perpendicular to the axial direction A. In Fig. 4, the pivot axis is perpendicular the drawing plane.

In the preferred embodiment shown here, the dispenser 1 also has a rear-part device 18, which exerts a restoring force on the stop element 14 at least substantially in the axial direction A against the attachment direction F. The rear part device 18 is arranged diametrically opposite the bearing 17 of the stop element 14 in the radial direction R. The rear part device 18 here has exactly one spring element 19 whose spring force acts as a restoring force on the stop element 14.

For this purpose, the rear part device 18 has a bolt 20 as a guide for the spring element 19. The bolt 20 extends in the axial direction A. The stop element 14 is arranged on the bolt 20 so that it is guided along the bolt 20 when the stop element 14 is moved. For this purpose, the stop element 14 has a lateral extension 21 with a recess 22 for the bolt 20. The spring element 19 is supported on the extension 21 and against the housing 2ab. Specifically, the stop element 14 by force in the mounting direction F -. B. by a user who applies a piston-cylinder unit 3 to the stop element 14 and then pushes further in the attachment direction F - be moved in just this direction and against the restoring force. If the force falls away - z. B. because the user no longer pushes - provides the rear part 18, in particular by means of the spring force of the spring member 19, the stop member 14 back against the mounting direction F. However, this movement is the held by the first fastening means 16 in its fixing position mounting portion 9 of the cylinder 8 blocked.

In the illustrated and preferred embodiment, the first attachment means 16 is movable from its fixing position into a release pitch for the attachment portion 9 by moving the locking member 12 in the attachment direction F in a release position. In this release division, a relative movement between the cylinder 8 and the housing 2 against the mounting direction F is executable. If the locking element 12 is not in its locking position, the mobility of the stop element 14 is released. This is an important function for releasing a piston-cylinder unit 3 from the dispenser 1. This release division of the first fastening device 16 (seventh state) is shown in FIG. 11, the longitudinal section through the locking element 12 being shown in FIG. 11.

In the illustrated and preferred embodiment, the first fastening device 16 has two pivotally mounted Zylindergreifhebel 23 which can engage behind the mounting portion 9 of the cylinder 8 in the fixing position of the first fastening means 16. The Zylindergreifhebel 23 are each carried out with two arms with a gripper arm 23a and an actuating arm 23b and pivotally mounted in the connecting region of the gripper arm 23a and actuating arm 23b. Spring elements 24 load the Zylindergreifhebel 23 such that the gripping arms 23a are pivoted in the absence of a counter force radially inwardly, in particular towards each other. The Zylindergreifhebel 23 are arranged and mounted so that the gripping arms 23 a when attaching a piston-cylinder unit 3 from the mounting portion 9 of Cylinders 8 can be pressed radially outward (first state as shown in Fig. 5) and then automatically engage behind the mounting portion 9, when the mounting portion 9 has been moved far enough in the mounting direction F. This second state is shown in FIG. The fixing position of the first fastening device 16 can be seen in FIGS. 6 to 14.

The gripper arms 23a are arranged here so that they are not visible in the illustrated vertical longitudinal sections. In addition, the gripping arms 23a are curved in cross section, so that it acts in Fig. 5 when not shown cut upper gripping arm 23a, as if this upper gripper arm 23a is not pressed far enough radially outward. In fact, in each case an inner side of the respective gripping arm 23a extends along the outside of the fastening section 9, wherein the inside of the respective gripping arm 23a does not have to rest completely against the outside of the fastening section 9.

For moving the first fastening device 16 from its fixing position into its release position by moving the locking element 12 in the attachment direction F, the actuating arms 23b of the cylinder gripper levers 23 of the first fastening device 16 each have a guide contour 25 into or on which a respective cam 26 of the locking element 12 is engaged can when the locking member 12 is moved in the attachment direction F in the release position. The guide contours 25 are formed and arranged so that when moving the locking member 12 in the mounting direction F, the actuating arms 23b are moved by means of the cam 26 radially inwardly. Thereby, the gripping arms 23a are moved radially outward.

To facilitate an automatic release and / or separation of a piston-cylinder unit 3, the dispenser 1 and its rear part 18 are designed so that by means of the rear part 18 attached to the dispenser 1 piston-cylinder unit 3 is separable from the dispenser 1, after the first fastening device 16 is moved from its fixing position into its release position and the piston-cylinder unit 3 has been released. For this purpose, the dispenser 1 and its rear part device 18 are designed so that the spring element 19 can decompress in the release division of the fastening device 16 and a separation of the piston-cylinder unit 3 from the dispenser 1 is not hindered.

In the illustrated and preferred embodiment, the dispenser 1, a second attachment means 27 which serves to fix the piston 7 on the dispenser 1. The second fastening device 27 is movable into a fixing position, in which the piston 7 is releasably connected to the piston actuator 10 of the dispenser 1 such that the piston 7 for receiving and / or dispensing fluid volumes by means of the piston actuator 10 relative to the cylinder 8 between a retracted Position and an extended position is movable. This fixing position of the second fastening device 27 is shown in FIGS. 9, 10, 12 and 13.

For this purpose, the second fastening device 27 has two pivotally mounted piston gripping levers 28, by means of which the piston 7 can be gripped when the second fastening device 27 is moved into its fixing position. Each piston gripping lever 28 here has a cutting roller with five cutting elements integrally formed on the cutting roller, which engage in the fixing position on the piston 7 when moving the piston gripping lever 28 and partially penetrate into the piston 7.

In the embodiment shown here and preferred embodiment, the second attachment means 27 is movable by moving the locking member 12 in the axial direction A of the fixing position in a release pitch and vice versa, wherein the piston 7 is not connected to the piston actuator 10 in the release division of the second fastening device 27. For this purpose, each piston gripping lever 28 has a control head 29 and the locking element 12 has a matching guide contour 30 and an axial extension 31. By means of the adjusting heads 29, the piston gripping levers 28 are pivotable. Each actuator head 29 is guided on the guide contour 30 of the locking element 12 when moving the locking element 12 and / or the piston actuator 10.

In the fixing position of the second fastening device 27, both adjusting heads 29 are in the guide contour 30, in particular in each case in a separate section between two walls of the guide contour 30, guided. In the release position, both adjusting heads 29 rest on the axial extension 31 and the housing 2 and are further apart than in the fixing position. If the second fastening device 27 is in its release position (FIG. 8) and the locking element 12 is then moved counter to the attachment direction F from its basic position to a second intermediate position, the adjusting heads 29 are moved along the axial extension 31 and the housing 2 into the guide contour 30 guided, and that each actuator head 29 in a separate section of the guide contour 30. The control heads 29 are moved towards each other. As a result, the piston gripping levers 28 are moved towards the pistons 7 until they engage or fix the pistons 7, in particular with their cutting rollers. Now the second fastening device 27 is in its fixing position (FIG. 9). In the preferred embodiment shown and preferred here, the second attachment means 27 is movably coupled to the piston actuator 10 and in its fixation position throughout the way it can move the piston actuator 10 can be guided by the locking member 12 to remain in its locked position , In particular, the extent of the guide contour 30 in the axial direction A is greater than the piston actuator 10 executable stroke.

If the piston 7 is in its retracted position and the second fastening device 27 is in its fixing position and the locking element 12 is then moved in the attachment direction F from the second to a first intermediate position, the adjusting heads 29 are guided along the guide contour 30 and ultimately out of it , so that the adjusting heads 29 are guided between the axial extension 31 and the housing 2. The adjusting heads 29 are moved apart or removed from each other. As a result, the piston gripping levers 28 are moved away from the piston 7, so that the piston 7 is no longer fixed. Now is the second fastening device 27 in its release position. The axial extension 31 fulfills a further object, namely, it limits the path of the locking element 12 when it is moved counter to the mounting direction F in its locking position, without a piston-cylinder unit is attached to the dispenser 1. In this case, the stop element 14 due to the missing cylinder 8 has no counter-stop. In order to prevent damage and to ensure operational safety, the axial extension 31 is designed and arranged so that when the locking element 12 strikes the stop element 14, it encounters a stop of the housing 2, whereby the locking element 12 and thus the stop element 14 can not be moved against the attachment direction F further.

In the illustrated and preferred embodiment, the dispenser 1 has means for optically detecting the attachment of a piston-cylinder unit 3 to the dispenser 1. These means comprise a light barrier 32 with a light beam source and a sensor for detecting light beams of the light beam source, wherein the light barrier 32 is arranged so that movement of the stop element 14 in the axial direction A of the light barrier 32 is detectable. For this purpose, the stop element 14 has a web 33 which is moved synchronously with the stop element 14. If the stop element 14 is moved or pressed far enough in the attachment direction F, the web 33 interrupts the light barrier 32. Without force acting in the attachment direction F on the stop element 14, the stop element 14 is in its initial position in which the light barrier 32 is not interrupted by the web 33 , Thus, the dispenser 1 can determine whether a piston-cylinder unit 3 is attached to the dispenser 1 or not. This detection allows the triggering of further steps, eg. B. moving the locking element 12th

In the illustrated and preferred embodiment, the piston actuator 10 for detecting a piston-side reference point on the piston 7 is movable until a stop 34 of the piston actuator 10 rests against an end face of the piston 7. This third state is shown in FIG. The absolute position of this piston-side reference point can be detected by means for determining the position. In the illustrated and preferred embodiment, the dispenser 1 comprises a detection device for automatically identifying the type of a piston-cylinder unit 3 attached to the dispenser 1. The detection device has a radial information reader, by means of which information of a radially oriented information carrier section 35 of the piston-cylinder unit 3 can be detected. In addition, the detection device has an axial information reader, by means of which information of an axially aligned information carrier section 36 of the piston-cylinder unit 3 can be detected. The radially oriented information carrier portion 35 is formed here as a radially aligned recess in the piston 7 and the axially aligned information carrier portion 36 as an axially aligned recess in an end face of the piston 7. By moving the locking element 12 from the first intermediate position to the second intermediate position, at least part of the radial information reader, namely a projection 37, can be introduced into the radially aligned recess 35 in the radial direction R. By moving the locking member 12 from its home position to the first intermediate position, at least a portion of the axial information reader is insertable into the axially aligned recess 36 in the axial direction A. In particular, the axial information reader has a detection element 38, which is at least partially insertable into the axially aligned recess 36 in the axial direction A. By means of the device for position determination, the depth of the axially aligned recess 36 can be determined. Based on the thus determined depth of the recess 36, the type of the piston-cylinder unit 3 can be at least partially identified.

The previously determined piston side reference point marks the starting point of a determination of the depth of the axially aligned recess 36.

The detection element 38 is elastically biased here by means of a spring 39 against the mounting direction F. By means of the locking element 12, moved from the first intermediate position to its basic position, that is Detection element 38 movable into a release position and preserved there. The locking element 12 holds the detection element 38 in its release position by a driver 40 of the locking element 12 against an extension 41 of the detection element 38 counteracts the force of the spring 39 and blocks movement of the detection element 38 in the direction of the spring force (ie against the mounting direction F).

By moving the locking element 12 against the attachment direction F from its basic position to the first intermediate position, movement of the detection element 38 is no longer blocked, so that the detection element 38 is pressed by the spring 39 onto the piston 7 and then into the axially aligned recess 36 until the detection element 38 hits the end of the axially aligned recess 36 and is blocked there. This fourth state is shown in FIG.

The axially aligned recess 36 is open here in the axial direction A upwards. The recess 36 is formed here in the form of a groove. It is therefore not a hole which is enclosed in the radial direction R. Rather, the recess 36 in the radial direction R is partially open to the outside, and that along the entire depth of the recess 36th

The dispenser 1 has other facilities, u. a. an electronic control device, a transmission device, a power supply device, a display device and an input device.

In the following, a preferred sequence of a method for releasably attaching a piston-cylinder unit 3 to the dispenser 1 is described.

At the beginning of the process, the locking element 12 is in its home position.

First, the attachment portion 9 of the cylinder 8 of the piston-cylinder unit 3 to the stop element 14 of the dispenser 1 by means of a at least in Essentially applied in axial direction A running movement, typically manually by a user. In this case, the piston 7 is moved through the passage 15 of the stop element 14. In addition, the gripping arms 23a of the cylinder gripping levers 23 are pressed radially outwards by the attachment section 9, so that the gripper arms 23a slide along the attachment section 9. This first state is shown in FIG.

In order not to hinder over-pressing of the piston-cylinder unit 3, the piston actuator 10 has been moved to a release position prior to application.

After application, the cylinder 8 is moved relative to the housing 2 in the mounting direction F. As a result, the stop element 14 is pressed in the mounting direction F against the return force of the rear sub 18. In this case, the spring element 19 of the rear-part device 18 is compressed.

If the cylinder 8 has moved far enough in the attachment direction F, grab the gripping arms 23 a behind the mounting portion 9, whereby the first fastening means 16 is moved to its fixing position, whereby the cylinder 8 is fixed to the dispenser 1, so that a relative movement between the cylinder 8 and the housing 2 is blocked against the mounting direction F and in the radial direction R. This second state is shown in FIG.

The movement of the stop element 14 in the attachment direction F is detected optically by means of the light barrier 32. Then, the piston actuator 10 is automatically moved against the mounting direction F on the piston 7 until the stop 34 of the piston actuator 10 rests against an end face of the piston 7. This third state is shown in FIG. In this case, the path traveled by the piston actuator 10 is determined. As a result, a piston-side reference point is detected, which is, so to speak, a path calibration which makes the method at least largely independent of differences in the dimensional tolerances of the parts of the piston-cylinder unit 3. The locking element 12 is then automatically moved against the mounting direction F in the first intermediate position. As a result, the detection element 38 is no longer blocked by the locking element 12 and at least partially inserted into the axially aligned recess 36 in the axial direction A. This fourth state is shown in FIG. The depth of this recess 36 is detected and the detected depth value used to identify the type of piston-cylinder unit 3.

The locking element 12 is then automatically moved against the mounting direction F in the second intermediate position. As a result, the second fastening device 27 is moved with its piston gripping levers 28 into its fixing position, in which the piston 7 is releasably connected to the piston actuator 10 such that the piston 7 is movable relative to the cylinder 8 for receiving and dispensing fluid volumes by means of the piston actuator 10. This fifth state is shown in FIG. At the same time, the projection 37 of the radial information reader is inserted into the radially aligned recess 35.

The locking element 12 is then automatically moved against the mounting direction F, in its locking position. This sixth state is shown in FIG. Here, the fixing portion 9 of the cylinder 8 is clamped between the Zylindergreifhebeln 23 and the stopper member 14, so that a relative movement between the cylinder 8 and the housing 2 in the axial direction A and in the radial direction R and is blocked in the circumferential direction.

Now, a relative movement between the piston 7 and the cylinder 8 by means of the piston actuator 10 can take place for receiving or discharging a fluid volume. To release the attached to the dispenser 1 piston-cylinder unit 3, the piston actuator 10 is moved so that the piston 7 is in its retracted position. Subsequently, the locking element 12 in the mounting direction F from its locking position on the second Intermediate position and the first intermediate position moves into its basic position. As a result, the second fastening device 27 is moved from its fixing position into its release position. The piston 7 is no longer connected to the piston actuator 10. In addition, the protrusion 37 of the radial information reader is moved out of the radially aligned recess 35 and the detection element 38 out of the axially aligned recess 36.

The locking element 12 is automatically moved in the attachment direction F further in the release position. As a result, the first fastening device 16 is moved from its fixing position into its release position. This seventh state is shown in FIG. 11. Now, a relative movement between the cylinder 8 and the housing 2 against the mounting direction F is freely executable.

Due to the restoring force of the return device 18 on the stop element 14, in particular the decompression of the spring element 19, the piston-cylinder unit 3 is separated from the dispenser 1. The movement of the stop element 14 initiated by the spring element 19 in the axial direction A is detected by the light barrier 32. The locking element 12 is automatically moved to its home position and the piston actuator 10 in its basic position, so that the described sequence with the attachment of a piston-cylinder unit 3 can start again.

LIST OF REFERENCE NUMBERS

1 dispenser

2 housings of 1

3 piston-cylinder unit

4 bottom of 1

5 opening of 1

6 system

7 pistons of 3

8 cylinders of 3

9 fixing section of 8

10 piston actuator of 1

1 1 drive for 10

12 locking element of 1

13 drive for 12

14 stop element of 1 1

15 passage of 14

16 first fastening device of FIG

17 bearings from 14

18 rear part of 1

19 spring element of 18

20 bolts of 18

21 extension of 14

22 recess of 14

23 cylinder grip levers of 16

23a gripper arm of 23

23b operating arm of 23

24 spring element of 23

25 guide contour of 23b

26 cams of 12

27 second fastening device of FIG

28 piston gripping lever of 27

29 control head from 27 30 guide contour of 12

31 axial extension of 12

32 photocell from 1

33 footbridge of 14

34 stop of 10

35 radially aligned recess of 7

36 axially aligned recess of 7

37 advantage

38 detection element

39 spring of 10

40 drivers from 12

41 extension of 38

A axial direction

F mounting direction

R radial direction

Claims

claims:

1 . Dispenser for receiving and dispensing fluid volumes, to which a piston-cylinder unit (3) with a piston (7) and a cylinder (8) releasably attachable by means of at least substantially in the axial direction (A) of the dispenser (1) extending movement is, where

the dispenser (1) has a piston actuator (10) for moving the piston (7) relative to the cylinder (8) and

the piston actuator (10) in the dispenser (1) is movably arranged and driven by a drive (1 1),

characterized in that

the dispenser (1) has a locking element (12) which is movably arranged in the dispenser (1) and driven by means of a further drive (13).

2. Dispenser according to claim 1, characterized in that the locking element (12) by means of the further drive (13) via a self-locking gear is driven, preferably wherein the locking element (12) is movable relative to or parallel to the piston actuator (10).

3. Dispenser according to claim 1 or 2, characterized in that the dispenser (1) has the following:

a housing (2),

a stop element (14) which is movable relative to the housing (2) at least substantially in the axial direction (A) and at least partially in the attachment direction (F) relative to the housing (2),

- wherein the dispenser (1) is formed so that when attaching the piston-cylinder unit (3) on the dispenser (1) a fastening portion (9) of the cylinder (8) into contact with the stop element (14) can be brought, and - A first fastening means (16) for fixing the cylinder (8) on

Dispenser (1), which is movable in a fixing position, in which the first Fastening means (16) blocks a relative movement between the cylinder (8) and the housing (2) against the mounting direction (F), and that the locking element (12) is movable to a locking position in which the locking element (12) is a relative movement between the Blocking element (14) and the housing (2) in the mounting direction (F) blocked.

4. Dispenser according to claim 3, characterized in that in the locking position of the locking element (12) of the fastening portion (9) of the cylinder (8) between the first fastening means (16) and the stop element (14) is clamped such that a relative movement between the cylinder (8) and the housing (2) in the axial direction (A), and optionally in the radial direction (R) and / or circumferential direction is blocked.

5. Dispenser according to one of claims 1 to 4, characterized in that the dispenser (1) comprises means for mechanical, electronic, inductive and / or optical detection of the attachment of a piston-cylinder unit (3) on the dispenser (1).

6. Dispenser according to claim 5, characterized in that the movement of the stop element (14) in the axial direction (A) by means of a dispenser (1) arranged sensor device, in particular a light barrier (32) is detectable, wherein the light barrier (32) is a light beam source and a sensor for detecting light beams of the light beam source.

7. Dispenser according to one of claims 3 to 6, characterized in that the dispenser (1) has a rear part device (18), which a restoring force on the stop element (14) at least substantially in the axial direction (A) against the mounting direction (F ) exercises.

8. Dispenser according to claim 7, characterized in that the rear part device (18) and the dispenser (1) are formed so that by means of the rear part means (18) on the dispenser (1) mounted piston-cylinder unit (3) from the dispenser (1) is separable.

9. Dispenser according to one of the preceding claims, characterized in that

the dispenser (1) has a housing (2) and a first fastening device (16) for fixing the cylinder (8) to the dispenser (1), and

the first fastening device (16)

- In a fixing position is movable, in which the first fastening means (16) blocks a relative movement between the cylinder (8) and the housing (2) against the mounting direction (F) and

- Is moved by moving the locking element (12) in a release position in which a relative movement between the cylinder (8) and the

Housing (2) against the mounting direction (F) is executable.

10. Dispenser according to one of the preceding claims, characterized in that

the dispenser (1) has a second fastening device (27) for fixing the piston (7) to the dispenser (1) and

the second fastening device (27)

- In a fixing position is movable, in which the piston (7) with the piston actuator (10) is releasably connected such that the piston (7) for receiving and / or dispensing fluid volumes by means of the piston actuator (10) relative to the cylinder (8 ) is movable, and

- Is moved by moving the locking element (12) from its fixing position into a release position and vice versa, wherein the piston (7) in the release position of the second fastening means (27) is not connected to the piston actuator (10).

1 1. Dispenser according to claim 10, characterized in that the second fastening means (27) is coupled in terms of movement with the piston actuator (10) and in its fixing position over the entire way, which they can perform when moving the piston actuator (10), of the locking element (12 ) Is so feasible that it remains in its fixing position.

12. Dispenser according to claim 10 or 1 1, characterized in that the second fastening means (27) has two pivotally mounted piston gripping levers (28) with cutting rollers, wherein by means of the piston gripping lever (28) during movement of the second fastening means (27) in its fixing position of Piston (7) is tangible.

13. Dispenser according to claim 12, characterized in that each piston gripping lever (28) has an actuating head (29) by means of which the respective piston gripping lever (28) is pivotable, each adjusting head (29) when moving the locking element (12) and / or the piston actuator (10) is guided on a guide contour (30) of the locking element (12).

14. Dispenser according to claim 13, characterized in that the extension of the guide contour (30) in the axial direction (A) is greater than the piston actuator (10) executable stroke.

15. Dispenser according to one of the preceding claims, characterized

the dispenser (1) has a detection device for automatically identifying the type of a piston-cylinder unit (3) attached to the dispenser (1),

in that the detection device has a radial information reader, by means of which information of a radially oriented information carrier section (35) of the piston-cylinder unit (3) can be detected, and

in that at least part of the radial information reader is movable by moving the locking element (12).

16. Dispenser according to one of the preceding claims, characterized

the dispenser (1) has a detection device for automatically identifying the type of a piston-cylinder unit (3) attached to the dispenser (1), in that the detection device has an axial information reader, by means of which information of an axially aligned information carrier section (36) of the piston-cylinder unit (3) can be detected, and

in that at least part of the axial information reader is movable by moving the locking element (12).

17. Dispenser according to claim 15 or 16, characterized in that by moving the locking element (12) at least a part of the radial information reader in a radially aligned recess (35) on a piston head of the piston-cylinder unit (3) in the radial direction (R) is insertable.

18. Dispenser according to one of claims 15 to 17, characterized in that by moving the locking element (12) at least a portion of the Axialinformationslesers in an axially aligned recess (36), in particular groove, in an end face of a piston head of the piston-cylinder unit (3) in the axial direction (A) is insertable.

19. A system for receiving and dispensing fluid volumes with a piston-cylinder unit (3) and a dispenser (1), wherein the piston-cylinder unit (3) - by means of at least substantially in the axial direction (A) of the dispenser ( 1) extending movement on the dispenser (1) is releasably attachable and

- Has a piston (7) and a cylinder (8) with a mounting portion (9),

characterized in that

the dispenser (1) is designed according to one of claims 1 to 18.

20. A method for releasably attaching a piston-cylinder unit (3) to a dispenser (1), wherein

- The piston-cylinder unit (3) has a piston (7) and a cylinder (8) with a mounting portion (9) and the dispenser (1) has a housing (2), a stop element (14), a first fastening device (16) for fixing the cylinder (8) to the dispenser (1) and a locking element (12),

the method comprising the following method steps:

a) applying the attachment portion (9) of the cylinder (8) of the piston-cylinder unit (3) to the stop element (14) of the dispenser (1) by means of at least substantially in the axial direction (A) of the dispenser (1) extending movement .

b) moving the first fastening device (16) of the dispenser (1) into a fixing position, whereby the cylinder (8) of the piston-cylinder unit (3) on the dispenser (1) by means of the first fastening device (16) of the dispenser (1) is fixed so that a relative movement between the cylinder (8) of the piston-cylinder unit (3) and the housing (2) of the dispenser (1) against the mounting direction (F) and optionally in the radial direction (R) is blocked, and c) moving the locking element (12) by means of a drive (13).

21. A method according to claim 20, wherein the dispenser (1) comprises detecting means for automatically identifying the type of a piston-cylinder unit (3) mounted on the dispenser (1),

wherein the detection means comprises a radial information reader, by means of which information of a radially oriented information carrier portion (35) of the piston-cylinder unit (3) is detectable and

wherein in step c) by moving the locking element (12) at least a part of the radial information reader is inserted into a radially aligned recess (35) on a piston head of the piston-cylinder unit (3) in the radial direction (R).

22. The method of claim 20 or 21, wherein the dispenser (1) comprises a detection device for automatically identifying the type of a dispenser (1) mounted on the piston-cylinder unit (3), wherein the detection means comprises an axial information reader, by means of which information of an axially aligned information carrier portion (36) of the piston-cylinder unit (3) can be detected, and

wherein in step c) by moving the locking element (12) at least a part of the Axialinformationslesers in an axially aligned recess (36), in particular groove, in an end face of a piston head of the piston-cylinder unit (3) in the axial direction (A) is introduced ,

23. The method according to any one of claims 20 to 22, wherein in step a) moving the stop element (14) in the mounting direction (F) mechanically, electronically, inductively and / or optically, preferably by means of a light barrier (32) is detected.

24. The method according to any one of claims 20 to 23, wherein in step c), preferably automatically after detecting a movement of the stop element

(14) in the attachment direction (F), the locking element (12) is moved to a locking position in which a relative movement between the stop element (14) and the housing (2) in the mounting direction (F) is blocked.

25. The method of claim 24, wherein in the locking position of the locking element (12) of the fastening portion (9) of the cylinder (8) between the first fastening means (16) and the stop element (14) is clamped, so that a relative movement between the cylinder (12). 8) and the housing (2) in the axial direction (A), and optionally in the radial direction (R) and / or circumferential direction is blocked.

26. The method according to any one of claims 20 to 25, wherein in step c) a second fastening means (27) of the dispenser (1) for fixing the piston (7) on the dispenser (1) moves by moving the locking element (12) in a fixing position is in which the piston (7) with a piston actuator (10) of the dispenser (1) is releasably connected such that the piston (7) for receiving and / or dispensing fluid volumes by means of a drive (1 1) driven piston actuator (10) is movable relative to the cylinder (8).

27. A method for releasing a on a dispenser (1) mounted piston-cylinder unit (3), wherein

- The piston-cylinder unit (3) has a piston (7) and a cylinder (8) and

- The dispenser (1) has a housing (2), a first fastening means (16) for fixing the cylinder (8) on the dispenser (1) and a locking element (12),

the method comprising the following method steps:

Moving the locking element (12) by means of a drive (13),

- Moving the first fastening means (16) from a fixing position in which the first fastening means (16) blocks a relative movement between the cylinder (8) and the housing (2) against the mounting direction (F), in a release pitch, in which a relative movement between the cylinder (8) and the housing (2) against the mounting direction (F) is executable and - moving the cylinder (8) relative to the housing (2) against the mounting direction (F).

28. The method of claim 27, wherein by moving the locking element (12) a second fastening means (27) of the dispenser (1) from a fixing position, in which the piston (7) with a piston actuator (10) of the dispenser (1) is releasably connected, that the piston (7) for receiving and / or dispensing fluid volumes by means of the piston actuator (10) is movable relative to the cylinder (8) is moved into a release pitch, in which the piston (7) not with the piston actuator (10) is connected.