WO2009083179A1

WO2009083179A1 - Fluidic device for controlled handling of liquids, and fluidic system with a fluidic device

Info

Publication number: WO2009083179A1
Application number: PCT/EP2008/010901
Authority: WO
Inventors: Heinz Kueck; Daniel Benz; Frank Wolter; Volker Mayer; Karl-Peter Fritz; Hans-Otto Maier; Rolf Heitmeier; Dominik Niedenzu
Original assignee: Hahn-Schickard-Gesellschaft für angewandte Forschung e.V.; B. Braun Melsungen Ag
Priority date: 2008-01-02
Filing date: 2008-12-19
Publication date: 2009-07-09
Also published as: DE102008003020A1; DE102008003020B4

Abstract

A fluidic device for conveying or determining the quantity of a liquid flowing from a fluidic device inlet (2) to a fluidic device outlet (4) along a fluid path running in a direction of flow (6) has a fluidic element (16) which is movable within the fluid path between a first position to a second position located in the direction of flow (6) downstream of the first position, and a fluidic device housing (8) enclosing the fluid path. The fluidic element (16) has a through flow opening (18) which has a first flow resistance when the fluidic element (16) moves from the first position (22) into the second position (24) and which has a second flow resistance differing from the first flow resistance when the fluidic element (16) moves from the second position (24) into the first position (22). The fluidic element (16) and the fluidic device housing (8) are designed in such a manner that the fluidic element is movable from the second position (24) to the first position (22) by means of a contactless drive.

Description

Fluidic fluid controlled fluid handling device and fluidic fluid device having a fluidic device

description

The present invention relates to a fluidic device and a fluidic system, by means of which a fluid can be conveyed and additionally or alternatively a quantity of fluid flowing through a fluidic device can be determined.

The prior art discloses a multiplicity of pumps or fluidic systems which can be used for conveying fluids. The sizes of the pumps vary from micromachined pumps of the lowest flow rate to very large pumps with high pump capacities, which are used, for example, in power plants.

The pumps belonging to the state of the art are predominantly complex constructions which contain the structure which causes the liquid transport, a drive and optionally a control or regulating device. Disadvantages of the high complexity of the known pumps are the high production costs, which virtually preclude the use of such pumps for single-use applications. In addition, reliability is reduced when many complex mechanical and electronic components need to work together.

In addition, a major problem is that usually the pumps used in the prior art require auxiliaries, such as lubricating oils or greases for their drive or the maintenance of the drive. These auxiliaries can either come into contact with the fluid to be delivered during normal operation or in the presence of a slight disturbance, and this thus contaminate. The known in the art pumps are predominantly driven mechanically, such as in a push rod of a conventional piston pump. The mechanical drive is also usually lubricated so that if a seal fails between the mechanical drive and the fluid, the fluid being pumped can be easily contaminated.

Equivalent considerations can be made when determining the flow rate of a fluid through a flowmeter. There, too, for example in the case of vane meters or the like, waves or mechanical elements are typically led outward from the volume of liquid over which contamination of the liquid can result. In general, systems which both serve to convey, ie, to pump, a liquid, and systems which are used to detect a flow of liquid or a quantity of liquid flowing through a device can be summarized by the term "fluidic devices."

In particular, in medical applications, it is impossible to use pumps or pumping elements or flow meters, which have even the lowest probability of contamination of the liquid to be delivered, such as a medical serum. In medical applications, because of the high level of hygiene, it is often required that a fluid-flow element to be used be used only once to ensure sterility.

There is thus a need for a fluidic device and a fluidic system that can be used in medical and process engineering applications or in single use applications. This need is solved by a fluidic device according to claim 1, a fluidic sensor according to claim 31 and by a fluidic system according to claim 34.

In some embodiments of the invention, a fluidic device is used to deliver a liquid which serves to convey fluid along a fluid path from a fluidic device inlet to a fluidic device outlet. The delivery of the liquid is achieved by means of a fluidic element which is movable along the fluid path between a first and a second position. The fluid path is enclosed by a fluidic device housing, which fluidly encloses the fluidic element so that fluid can be delivered when the fluidic element is moved from the first position to the second position.

In some embodiments, the fluidic element is arranged to be freely movable in the fluid path. The fluidic element is not mechanically connected to the fluidic device housing. Consequently, there is no direct mechanical connection with the fluidic device housing, by which movement of the fluidic element is restricted. In other words, the fluidic element is not mechanically connected to the fluidic device housing in a direction perpendicular to the flow direction.

In other embodiments, the fluidic element is used to measure or determine a flow rate or volume of a fluid flowing through the fluidic device. For this purpose, the fluidic element can be equipped with a valve which has an opening force

(For example, because a gasket is mechanically biased) requires greater than a force on the valve caused by the liquid flowing through the fluidic device. The valve thus remains closed when the fluidic element moves in the flow direction from the first position to the second position. If the fluid ment detected at the second position, it is moved from the second position back to the first position. The bias of the valve is selected such that a dynamic pressure caused by the fluid exerts a force on the valve which is greater than the force required to open the valve, so that the fluid element moves relative to the fluid to the first position can. If such movement cycles are performed multiple times, the number of strokes or the movements from the second to the first position is directly a measure of what volume of liquid has flowed through the fluidic device.

In some embodiments, the fluidic element is at least partially made of a magnetizable material so that the fluidic element can be moved from the first position to the second position or from the second position to the first position by applying an electromagnetically induced force to the fluidic element along the fluid path , With the use of such a fluidic device, liquid can be delivered without the driving force (the source of the electromagnetic fields) actually causing the driving force coming into direct contact with the fluid or fluid to be delivered. Furthermore, it is conceivable to move the fluidic element by means of a targeted accelerated movement of the fluidic device housing relative thereto, because the fluidic element wishes to remain in its state of motion due to its inertia. This can be done for example by a periodic movement or by shock processes.

In some embodiments, the fluidic element has a bore or fluid passage through which the fluid to be delivered can flow. In further embodiments, the liquid channel is secured by a seal which is designed so that liquid through the liquid channel only in a predetermined direction can flow. This is the flow direction, so that when the piston or the fluid element is moved in the flow direction, ie relative to the fluidic device housing located in the fluid against the flow direction, the seal closes and the liquid located in front of the piston is displaced from the fluidic. On the other hand, when the piston is moved counter to the flow direction, the valve opens and allows liquid to be newly delivered through the liquid channel to flow into the volume located in front of the fluidic element, so that upon subsequent movement of the fluidic element from the first to the second position, this liquid can be displaced or promoted.

In some embodiments, only the movement of the fluidic element in the direction opposite to the direction of flow (from the 2nd to the 1st position) is achieved by electromagnetic force. If the relevant electromagnetic force is no longer applied, for example by a magnetic field being switched off, the fluidic element is moved by mechanical components, for example by a prestressed spring, along the fluid path from the first position to the second position. In this case, the flow rate, ie the amount of liquid delivered per unit time, can be adjusted in a simple manner by suitably dimensioning the mechanical force (for example the spring force) acting on the fluidic element relative to the flow resistance at the outlet or inlet of the fluidic device. If, for example, the flow resistance is high, the flow rate per unit time is low, so a single delivery stroke takes a comparatively long time with a small flow rate.

In some embodiments, a check valve disposed in the fluid path within the fluidic device or the valve located on the fluidic element is already biased, ie, the force used to open the Valve is required, is increased by appropriate measures, so that liquid can be conveyed reliably even if the pressure of the fluid at Fluidikvor- direction input is greater than the pressure of the fluid at Fluidikvorrichtungsausgang.

Some embodiments include a fluidic device and a drive device that is configured to be reversibly coupled to the fluidic device, wherein the drive device is configured separately from the fluidic device. The drive device, in some embodiments, includes means for generating an electromagnetic force or electromagnetic field by which the fluidic element is moved from the second to the first position. Since the drive device, which has the comparatively expensive electromagnetic field generating and electromagnetic field monitoring electronics, is reversibly couplable to the fluidic device, a plurality of fluidic devices can be operated by only one drive device. In this case, the individual fluidic devices can be designed as low-cost, simple components.

In addition, at any point in time, the drive device, or component of the drive device which causes the drive force, is physically separated from the fluid path and thus from the fluid to be delivered.

In some embodiments, the fluidic device or drive device further comprises a detection device configured to determine the position of the fluidic element within the fluidic device. In this case, the delivery rate per unit time can be determined at any time, or it can be detected whether the fluidic device runs within its specification and works without problems. For this purpose, the detection device determines, for example, the per stroke promoted Volume and counting counts the number of strokes. Moreover, deviation from the normal operation state can be prevented by properly controlling the drive device based on the results of the detection order.

Preferred embodiments of the present invention will be explained in more detail below with reference to the accompanying drawings. Show it:

Fig. Ia an embodiment of a fluidic device;

FIG. 1b shows a further embodiment of a fluidic device; FIG.

Fig. Ic is a sectional view of the fluidic device of Fig. Ib;

Fig. 2 embodiments of fluidic elements;

3 shows embodiments of valves attached to the fluidic element;

4 shows a further exemplary embodiment of a valve attached to the fluidic element;

5 shows further embodiments of attached to the fluidic element valves.

6 shows a further exemplary embodiment of a valve attached to the fluidic element;

Fig. 7a embodiments for in the Fluidikvorrich- and 7b direction attached check valves;

8a further exemplary embodiments for check valves mounted in the fluidic and 8b devices; FIG. 9 shows an example of the dimensioning of flow resistances for achieving a predetermined delivery stroke; FIG.

10 shows an exemplary embodiment of a fluidic system comprising a fluidic device and a drive device;

11 shows an alternative embodiment of a fluidic system;

12 shows a further embodiment of a fluidic system; and

Fig. 13 shows another embodiment of a fluidic system.

1 a shows a sectional view of an embodiment of a fluidic device for conveying a fluid from a fluidic device inlet 2 to a fluidic device outlet 4. The fluidic device is shown on the one hand in a hatched representation for ease of understanding and on the other hand in a representation, in which only the contours of the individual elements are visible. The fluidic device serves to convey fluid from the fluidic device inlet 2 to the fluidic device outlet 4, wherein the fluid within the fluidic device is conveyed in a flow direction 6 along a fluid path. The fluid path consists, as explained in more detail in the following sections, of a series of different fluid path sections with varying cross sections. In the case of the fluidic device shown in FIG. 1, which is rotationally symmetrical about a centrally extending axis of symmetry, the individual fluid path sections consist in particular of cylindrical fluid channels of varying diameter. Before a more detailed discussion of the fluidic device shown in Fig. Ia it should be noted that in Fig. 1 and in the following figures functionally similar or functionally identical elements are provided with the same reference numerals and that in particular the description of the individual function-like elements within the different embodiments mutually is applicable to each other.

The fluidic device shown in Fig. Ia has a fluidic device housing 8, which is formed in several pieces in the example shown, if this is necessary for reasons of the geometry of the housing for assembly. In alternative embodiments, however, the fluidic device housing can also be made in one piece. Within the fluidic device housing 8, the fluid path formed by the fluidic device housing 8 is logically subdividable into a plurality of fluid path segments 10a-f. Due to the rotationally symmetric geometry of the fluidic device, the individual fluid path segments 10a to 10f are each formed of concentric cylindrical volumes which adjoin one another along the fluid path. Although rotationally symmetric geometries are discussed in the example shown in FIG. 1 and with reference to the exemplary embodiments described below, rotational symmetry is not a mandatory prerequisite. Rather, it is also conceivable, for example, to use a fluid path or fluid path segments which have a square or rectangular cross section.

At the fluidic device inlet 2, the fluid first flows through the fluid path segment 10a, which is adjoined in the flow direction by the fluid path segment 10b, which has a narrowed cross section. The narrowing of the cross-section can be used to suitably dimension the dynamic properties, that is to say the pumping properties of the fluidic device, as will be explained in more detail below. The fluid path segment 10c, which adjoins the fluid path segment 10b in the flow direction, is separated therefrom by a check valve 12, which ensures that fluid can only move in the flow direction 6 through the fluidic device. Fluid path segment 10c has an expanded cross-section and serves to house a spring 14 used as a restoring device, which has a stop on the input side, and which rests on the opposite side of the input side of the fluid element to exert on this acting in the flow direction restoring force. The spring 14 is installed in a prestressed state or is tensioned by movement of the fluidic element 16 counter to the flow direction 6. The fluidic element is at least partially made of magnetizable material. That is, although it is indicated in Fig. 1 that the fluidic element is made in one piece, it is possible in further embodiments that the fluidic element 16 consists of several different lent material components. For example, it is conceivable that the fluidic element 16 is partially formed of magnetizable material and partly of dielectric material.

The fluidic element 16 further has a central bore designed as a liquid passage 18 which extends in the flow direction 6 through the entire fluidic 16, so that liquid can flow through the fluidic 16. The fluidic element 16 itself is located in the fluid path segment 10 d, which has a diameter which is dimensioned such that the fluidic device housing 8 terminates fluidically with the outer diameter of the fluidic element 16. In other words, no liquid can flow past at the edges of the fluidic element 16. The fluidic element 16 further has a seal 20, which has the function of a check valve, which allows fluid to flow only in the flow direction 6 through the fluidic 16. As can be seen from the drawing in FIG. 1 a, the fluidic element 16 is thus freely movable within the fluid path segment 10 d, for example from a first position 22 defined by an input-side stop to a second position 24 defined by a first position output-side stop is defined, can be moved.

As described above, the fluidic element within the fluid path segment 10d is free to move. This means that it is not necessary to mechanically fix the fluidic element in a direction perpendicular to the fluid path with respect to the fluidic device housing. This considerably simplifies the construction of the fluidic device housing, so that this can be produced inexpensively in large numbers. Further, it thereby becomes possible to adjust the pumping characteristics substantially by the flow resistances along the fluid path within the fluidic device, without having to take into account any mechanical damping that might be generated by a fixation of the fluidic element with respect to the fluidic device housing.

Fluid path segment 10e has a restricted cross-section with fluid path segment 10d and, similar to fluid path segment 10b, may be used to adjust the dynamic pumping characteristics.

The fluidic device outlet 4 is formed by fluid path segment 10f.

In the fluidic device, when the fluidic element 16 moves from the second position 24 to the first position 22, the two flow-directionally-permeable valves 12 and 20 cooperate such that fluid can not escape on the inlet side, the fluid passing through the fluid channel 18 of the fluidic element through the fluid particles ment flows. As a result, liquid is in a volume of the fluid path segment 10d located in the exit direction in front of the fluidic element 16 when the fluidic element 16 has completed its return movement, ie is at the first position 22. This state defines the beginning of a delivery stroke during which liquid is conveyed through the outlet 4.

This is achieved in that the spring, which is biased during the movement of the fluidic element 16 from the second position 24 to the first position 22 by the fluidic 16, in the flow direction 6 exerts a force on the fluidic 16, so that this during a delivery stroke the displaced in front of the liquid volume in the direction of Fluidikvorrichtungsausgangs 4. This is possible because the valve 20 blocks in the direction of flow 6 during a movement of the fluidic element 16, so that the fluid can not flow back through the fluid channel 18. At the same time, the check valve 12 opens, so that new liquid is sucked in from the inlet 2 by the negative pressure arising behind the fluidic element 16, which during the delivery stroke fills the volume released in the fluid path segment 10d. In this case, the conveying speed, that is, the liquid volume displaced by the fluidic element 16 per unit of time, is determined by the spring force and the flow resistance of the fluid path segment having the greatest flow resistance. In the case shown in Fig. Ia, this is fluid path segment 10b which has the smallest diameter. Since the spring force of the spring 14 is approximately constant over the entire path, the conveying speed, ie the speed with which the fluidic element 16 is moved, can be easily determined by the dimensioning of the components used, that is to say in particular the spring and set the maximum flow resistance (the smallest used diameter along the fluid path). This can be achieved by a simple geometric dimensioning of the components used, without, for example, a complicated electronic control for a drive motor would be required. The only requirement is that the fluidic element 16 is moved from the second position 24 to the first position 22 at the beginning of a delivery stroke. This can be achieved when the fluidic element 16 is at least partially made of a magnetizable material, for example by generating a magnetic field in the fluid path segment 10c and 10d, through which the fluidic element 16 is pulled to the first position 22 while simultaneously biasing the spring 14.

For the speed with which the fluidic element 16 is moved from the second position 24 to the first position 22, on the one hand, the magnitude of the electromagnetic force exerted on the fluidic element is decisive. On the other hand, in the return movement of the electromagnetic force, the flow resistance of the liquid channel 18, through which the displaced liquid must flow, counteracts. Consequently, by suitable dimensioning of the flow resistance of the fluid channel 18, the speed of the return movement of the fluidic element 16 can be adjusted. If the flow resistance of the liquid channel 18 is low, an almost continuous operation of the fluidic device can be achieved, because then the return movement of the fluidic 16 is hardly hindered or attenuated so that it takes place extremely fast compared to the forward movement. That is, short return movements alternate with long-lasting forward movements, so that there is a quasi-continuous flow in the fluidic device. This is often desirable, especially in medical applications. As described above, this advantageous property can be achieved by suitably selecting only the geometric dimensions of the fluidic device used. This sets Others a complex electronic control for a fluidic device driving motor superfluous.

A conveying action during a delivery stroke can be achieved in an alternative embodiment of the invention even if the fluidic element has no valve 20. This is possible if the flow resistance of the throughflow opening is greater during a movement of the fluid element from the first 22 to the second 24 position than the flow resistance between the fluidic element and the fluidic device output 4. Such a configuration may in alternative embodiments of the invention itself without valve 20 a net pumping action can be achieved.

Likewise, in further embodiments, the check valve can be dispensed with if the flow resistance of the throughflow opening is smaller during a movement of the fluidic element from the second (24) to the first (22) position than the flow resistance between the fluidic element and the fluidic device input (4), so that liquid flows through the flow-through opening during the return movement.

As a driving device serving to apply the force required for retrieving the fluidic element 16 to the fluidic element 16, as mentioned above, a magnetic field generating device may be used. These may be, for example, coils which are arranged outside the fluidic device and generate a magnetic field running parallel to the flow direction. In this case, the drive device does not come into physical contact with the liquid to be delivered. The drive device may be physically separate from the fluidic device so that a plurality of fluidic devices, possibly only once used, may be operated by only a single drive device. This has the advantage that the existing in the drive device Electronics, which is a costly component of a pumping system or a fluidic system, only needs to be generated once. The fluidic device shown in FIG. 1 has the property, in particular in the medical field, that the elements or components required for the drive do not come into direct contact with the fluid to be delivered at any time, so that in the case of a single use Fluidic device with a matching drive device, the absolute sterility of the pumped liquid or the funded fluid can be ensured.

FIG. 1b shows a further exemplary embodiment of a fluidic device, which is based on the principle already discussed in detail with reference to FIG. 1a. In the following, only the components of different functions are described in order to avoid a redundant representation of the individual features or components. The fluidic element 16 is separated in FIG. 1 b into two functionally different regions (a drive region 16 a and a sealing region 16 b). In this case, the two areas can both be formed in multiple pieces, that is, assembled from discrete individual components, as well as manufactured in one piece. The drive region 16a facing the fluidic device inlet 2 serves to drive the fluidic element 16, ie it has all the devices and means which make it possible to drive the fluidic element 16 without contact. The fluidic device outlet 4 facing the sealing region 16b of the fluidic element 16 serves to ensure the fluidic seal upon movement of the fluidic element from the first position 22 to the second position 24.

The geometric dimensioning of the sealing region 16 or of the fluid path segment 10g, within which the sealing region 16b of the fluidic element 16 is moved, makes it possible to adapt the dynamic properties of the fluidic device to the most varied flow rates, by the Cross section of the sealing portion 16b is selected accordingly. With regard to the appropriate dimensioning of the different cross sections along the fluid path, reference is here made to the statements made in FIG. 1a. By separating the fluidic element 16 into two different functional regions, however, the cross section or the diameter of the drive region 16a can always remain constant, so that, despite the high variability that can be achieved, the same drive device can always be used, even if the flow rates change greatly. This allows a much higher flexibility of the overall system while reducing costs can be achieved. During the return movement, ie during the movement from the second position 24 to the first position 22, it is desirable to additionally reduce the flow resistance, which is initially determined by the flow resistance of the flow opening 18, which serves as a central bore through the drive region 16a and Sealing area 16b is executed. In order to additionally reduce the flow resistance for the return stroke, additional channels 50a and 50b are provided in the drive region 16a in the exemplary embodiment shown in FIG. 1b, as can be seen from the sectional view AA 'shown in FIG. The fluidic element 16 has channels or flow-through openings 50a and 50b which extend over the entire length, ie the axial extent, of the cylindrical sealing region 16b. In this case, the geometric shape of the throughflow openings or of the channels 50a and 50b shown in FIG. 1c is to be understood merely as an example. These can also have any other geometric shape, for example, rectangular, if they are introduced by means of a milling cutter.

Through the channels 50a and 50b, an additional minimization of the flow resistance can be achieved, as is advantageous for a quick return movement. Also shown in FIG. 1b is an active check valve as an alternative to the use of a passive valve. The active valve comprises several functional components. These are on the one hand, the passive valve 12 and a support 80 a, which is arranged along the flow direction after the valve 12 and coupled with this mechanical. The carrier 80a is made of magnetizable material and can be acted upon by an electromagnetic field with a force acting counter to the flow direction 6 force. By adjusting this force, the valve 12 can be biased, the force of the bias being adjustable within wide limits over the magnitude of the electric field. In particular, in some embodiments, the force on the carrier 80a may be generated from the same field that also serves to move the fluidic element 16. In Fig. Ib a magnetizable guide member 80b is provided for this purpose, which directs the magnetic flux in the form of a yoke. As a result, the support 80a can be pressed against the valve 12 with a predetermined, adjustable force so that it opens only when an adjustable force is reached. This makes it possible to adapt the dynamic properties of the fluidic device even more precisely to the conditions.

In alternative embodiments of the invention, a fluidic device may also be used as a fluidic sensor. In this case, it is possible to dispense with a drive of the fluidic element in the flow direction and to design the fluidic element in such a way that it is entrained by the fluid and moved from the first to the second position. It is not necessary for the fluidic element to have a flow-through opening. In some embodiments, the fluidic element may for example have a smaller diameter than the inner diameter of the housing. When the fluidic element is detected at the second (24) position, knowing the geometry of such a fluidic sensor, the volume of fluid that may be calculated during a time period may be calculated Movement of the fluidic element has flowed from the first to the second position by the fluidic sensor. By means of a drive device, the fluidic element (16) can be moved back from the second (24) to the first position (22) in order to enable a continuous operation of the sensor or a continuous flow measurement.

FIG. 2 shows two ways in which the fluidic element 16 can be attached or arranged in a fluid-tight manner within the fluid path segment 10d.

In the first alternative shown above, the fluidic element is made with a diameter corresponding to the diameter of the fluid path segment 10d with minimal tolerance so that no gap is formed between the cylindrical diameter of the fluidic element 16 and the wall of the fluid path segment or fluidic device housing 8.

2, the diameter of the fluidic element 16 is smaller than the diameter of the fluidic device housing 8. In order to nevertheless achieve a good seal, a groove 28 is milled into the fluidic element 16 into which an O-ring 30 is inserted, which ensures the seal between the fluidic 16 and the wall of the Fluidikvorrichtungsgehäuses 8. As an alternative to the O-ring 30 shown in FIG. 2 below, piston rings may also be used.

In other words, the seal can be done by a very precise storage of the piston, in which the remaining, annular gap, between the piston and the housing wall is not greater than, for example, about 10 microns. Alternatively, to seal the annular gap between the piston and the cylinder of the fluidic device housing, one or more O-rings may be used, as outlined in FIG. 2 below. To minimize the friction between the piston and Housing can still be air between O-ring and groove on the piston without pre-pressing the O-ring. Instead of O-rings also piston rings can be used.

FIG. 3 shows some embodiments of a seal 20 or of valves 20 that can be used to seal the fluid element 16 during the delivery stroke. In this case, the fluidic element 16 is partially shown in a 3-dimensional perspective view and in a sectional view. Fig. 3 above shows the possibility of using a flap cap seal 40 attached to a base of the cylindrical fluidic element 16. The, for example made of rubber, flap cover seal 40 has a central cover portion 42 which is connected via two webs 44a and 44b with an edge region of the flap cover seal 40. The flap lid 42, with the exception of the two webs 44a and 44b from the rest of the flap cover gasket 40 completely separated by a circumferential groove. If the material of the webs 44a and 44b is flexible, the flap lid 42 can lift under a force in the direction of flow 6, so that the liquid can flow in the flow direction 6 through the liquid channel 18 of the fluidic. In this case, the flexibility of the webs 44a and 44b may be selected, for example, such that only the pressure of the liquid acting on the flap lid 42 by the return movement of the fluidic element 16 is sufficient to open the flap cover gasket 40. During the conveying movement, the flap cover gasket 40 closes automatically when a pressure against the flow direction 46 acts on the flap cover gasket 40. In order to improve the closing of the flap cover gasket 40, the contact surface of the flap cover 42 on the fluidic element 16 can be minimized so that a greater contact force is achieved with the same pressure. This can, as for example in the sectional view shown in Fig. 3 in the middle part can be realized by concentric annular grooves 48 in the Flap cover seal 40 facing side of the Fluidikele- element 16 are milled. 3, in addition to an enlarged view of the flap cap seal 40, shows an alternative example of a seal that may be used to ensure a check function on the fluidic element 16.

The cross-diaphragm 50 shown in Fig. 3 bottom left has the same operation as the flap cover seal 40. The only difference is that the central opening membrane part 50 of the cross-membrane of four webs 52a to 52d, which are arranged in a cross shape, with the rest of the cross-membrane 50 is connected.

In other words, the flap lid seal attached to the end face of the piston forms a valve with the piston, so that the medium can only flow in one direction. This mode of operation is comparable to that of a check valve, so that the medium can only flow in the direction of flow through the liquid channel 18 of the fluidic element 16. In some embodiments, the seal is also airtight to ensure good self-priming of the fluidic system when used as a pump. In some embodiments, the piston on the front side on small annular grooves, which serve to increase the surface pressure of the sealing part of the flap cover seal and the cross-diaphragm seal.

In summary, therefore, the opening and closing times of the valve can be set in a simple manner via the material thickness, the web width or the Shore hardness of the material used to produce the seal. In terms of abstract terms, the seal operated with the function of a check valve serves to increase the flow resistance against the direction of flow when the fluid element moves from the first position 22 into the second position 24 to approximately infinity. hen. When the return movement of the fluidic element, however, this remains small, since the seal used then opens automatically.

As already mentioned, a cylindrical fluid channel 18 is not a prerequisite for the successful application of the inventive concept. Rather, a liquid channel 18 with a different cross section can also be used. In addition, it is also possible to use a plurality of axial bores in order to achieve a desired cross section of the liquid-conducting parts within the fluidic element 16. A general advantage of axial bores is that they have a low flow resistance.

Fig. 4 shows an alternative embodiment of a fluidic element 16 with integrated valve, which has a check valve corresponding action. In the case shown in Fig. 4, the valve is formed by an arrangement of a spring 60 and a ball 62, wherein the ball is loaded by the spring and is pressed against a matched to the diameter of the ball 62 ball seat 64. In this case, the spring 60 and the ball 62 are arranged, for example, within a stepped bore 66 in the fluidic element. On the side facing away from the ball seat 64, the spring 60 is supported, for example, by a stop 68 introduced into the fluidic element 16. If a pressure is exerted on the ball 62 by the fluid to be displaced in the direction of flow 6 which is strong enough to compress the spring 60, the valve formed by the ball 62 and the ball seat 64 opens and allows fluid to flow in the direction of flow 6 the fluidic element 16 flows. In a flow opposite to the flow direction 6, the force exerted by the spring 60 on the ball 62 force is additionally reinforced by the fluid pressure, so that the sealing effect of the valve shown in Fig. 4 is still improved. In other words, the piston shown in FIG. 4 or the fluidic element shown in FIG. 4 has an axial stepped bore, one step serving as a sealing seat or stop for a further movable element located in the bore. The movable element is z. B. pressed by a coil spring on the sealing seat or the step. The spring itself is also supported on a stop at the other end. The movable sealing element can be significantly smaller in diameter than the bore, in order to achieve the smallest possible flow resistance. The inertia of the movable sealing element reinforces the sealing effect in addition to the spring force when the piston or the fluidic element 16 moves along the flow direction 6.

Figures 5a to 5d show further embodiments of seals associated with the fluidic element 16 wherein the seals are biased so that the pressure applied to the seal needed to open the seal is opposite that shown in Figs 4 discussed embodiments is increased. 5 a to c show examples of fluidic elements 16 in a sectional view, while FIG. 5 d shows a possibility of implementation by means of a special sealing element.

By the measures shown in FIGS. 5a to 5d, the seal or the check valve is mechanically biased, so that the opening pressure required for opening the valve or the seal is increased. This can be used to adjust the dynamic properties of the system so as to cause, for example, an extension of the return movement of the fluidic element 16. Moreover, when the opening pressure of the valve is increased, the fluidic system, when used as a pump, can still provide controlled delivery even when the fluid reservoir located at the fluidic device inlet has a higher static pressure than the outlet of the fluidic device. In such a case must the seal 20 of the fluidic device and / or the check valve 12 of the fluidic device withstand the overpressure at the inlet to ^; prevent the valves from opening and the fluid from flowing through the fluidic device regardless of the delivery strokes made by the fluidic element.

In the case shown in FIG. 5 a, the diaphragm 50 of the cross-diaphragm seal described in FIG. 3 is prestressed by forming pins 70 projecting from the fluidic element 16 out of the material of the fluidic element 16 which blocks the cross-diaphragm against the restoring action of the cross-diaphragm webs 52 a to 52 d ahead steer.

Fig. 5b shows an example of how the opening force for a flap cover gasket can be increased by deflecting the flap cover gasket or flap cover 42 of the flap cover gasket against the restoring force of the webs 44a and 44b. This is achieved by attaching asymmetrically shaped pegs 72a and 72b to the fluidic element 16 which provide for pilot deflection of the flap cap seal. When using a flap lid seal, it must be noted that the elements causing the deflection must be shaped in such a way that the flap lid seal closes tightly with the fluidic element 16 in the pre-steered state. Contrary to the case shown in FIG. 5a, these elements can therefore not be symmetrical.

In the case of the spring-loaded ball element 62, which is shown again in Fig. 5c, an increase in the spring stiffness or the bias of the spring is sufficient to increase the pressure required to open the seal.

Fig. 5d shows an embodiment of a seal in which the bias is achieved by the shape of the gasket itself by having in the central region a protruding structure 74 which is comparable to a nose and that leads to a forward deflection of the seal when the nose is placed on a solid abutment.

The seals presented by way of example in FIG. 3 can thus be biased in different words by various measures. This can be achieved, for example, by means of a pin protruding at the end face of the piston or fluid element 16, which biases the flap cover of the flap cover gasket or the cross-membrane. The preload force can be varied by the pin height, the material thickness, the material hardness and the web widths of the seals. In the case shown in Fig. 5c, the biasing force of the spring can be selected accordingly, which can be done on the one hand on the variation of the spring stiffness and on the other via the variation of the forward steering.

Alternatively, a gasket may be made having a protruding nose from the gasket surface so that the bias is directly generated by the gasket in question itself.

FIG. 6 shows, in a cutaway view of the fluidic device shown in FIG. 1, a further possibility of achieving a prestressing of the seal 20 of the fluidic element 16. According to the embodiment shown in Fig. 6, the bias voltage is achieved in that an additional biasing spring 80 which is mounted on an abutment 82, against the flow direction 6 presses on the sealing element 20 of the fluidic 16. A variation of the bias voltage can, as just discussed with reference to FIG. 5 case, be achieved via a change in the spring hardness or the bias of the spring.

As shown in FIG. 6, therefore, an additional mechanical spring, which is supported on a stop on the fluidic device outlet, presses against the sealing membrane 20 of the piston valve (for example flap cover or cross-diaphragm). About the spring length and the spring constant leaves the opening pressure of the piston valve or the valve bias vary. The minimum preload force results from the required dynamic boost pressure. Due to the boost pressure, a safe closing of the check valve at the fluidic device inlet is to be achieved during the return movement of the piston, even at negative delivery heights. As already mentioned above, negative delivery heights mean that the fluid level of the medium flowing through is higher at the inlet of the fluidic device than at the outlet of the fluidic device. For example, up to 0.2 bar pre-pressure can be compensated.

The mechanical preloading of the valve 20, as illustrated with reference to FIGS. 5a to 5c and 6, makes it possible, in particular, to use embodiments of fluidic devices for measuring or determining the flow of a fluid through the fluidic device. This can be dispensed with a drive device. The fluidic element 16, or the force required to open the valve 20 of the fluidic element 16, is dimensioned such that when the fluid is flowing through the fluidic device, the seal remains closed and the fluidic element 16 is thus driven by the fluid flow moved first position 22 to the second position 24. If it is detected by an external detector that the fluidic element 16 has arrived at the second position 24, this information can be used to move the fluidic element back from the second position to the first position. If the valve is suitably biased, the additional back pressure of the fluid generates a force high enough to open the valve 20, so that the number of fluid cycles per unit of time, ie, the stroke frequency, is used to calculate the amount of fluid flowing through the fluidic device can.

FIGS. 7a and 7b show an enlarged detail of a fluidic device already discussed with reference to FIG. direction and, in particular, the fluidic device inlet 2 with the two first fluid path segments 10a and 10b and the check valve 12 adjoining the fluid path segment 10b. FIGS. 7a and 7b merely show sectional enlargements of the two previously discussed implementations with flap lid gasket 12a (FIG. 7a) and cross-diaphragm seal 12b (FIG. 7b), reference should be made to the explanations of the preceding figures with respect to the operation of the components shown in FIGS. 7a and 7b.

The check valve 12, which may be made of rubber, for example, can be inserted, glued or fixed in a recess in the housing. The seal placed over the bore (fluid path segment 10b) in the housing acts like a check valve. This check valve 12 seals in some embodiments, even at very low pressure difference airtight. As already discussed with reference to the valve of the fluidic element 16, the opening and closing times of the valve can be adjusted via the material thickness and the web widths of the hinged lid or the cross-diaphragm.

In addition, the opening and closing pressure can be influenced by the material thickness, the web width of the webs of the seals and the Shore hardness of a possibly used sealing rubber.

FIGS. 8a and 8b show in a sectional view the detail enlargements already discussed with reference to FIGS. 7a and 7b in a sectional view, the possibility additionally being illustrated in FIGS. 8a and 8b also of the check valves 12a and 12b at the inlet of the fluidic bias device by means of suitable material tabs 14a and 14b, so that the pressure required to open the valve is increased. The resulting positive consequences for the overall arrangement have already been described in connection with the fluidic valve. Elements 16 is discussed so that reference is made at this point to what has been said for these embodiments.

As with the fluidic element 16, the flap-end diskless 12b and the cross-diaphragm 12a are slightly biased by means of a protruding pin 14a and 14b on the fluidic device housing 8, respectively. In the flap lid 12b, the pin surface 14b should be inclined in accordance with the setting angle in order to ensure complete seating of the flap lid 12b. Again, the biasing force on the pin height, the material thickness, the material hardness and the web widths of the seals vary. With the measure name of the prestressing of the seals described in FIGS. 8a and 8b, a secure closing of the check valve at the fluidic device inlet can also be achieved at negative delivery heights.

9 clarifies the relationship between the dimensioning of the flow resistances of the fluid path segments and the resulting duty cycle of the fluidic device on the basis of the detail enlargement of the fluidic device housing 8 discussed in FIG. 7a. To clarify the relationship, the time profile of the current required to operate a magnet 90, which generates the magnetic field which causes the return of the fluidic element 16, is shown in FIG. 9 below.

The duty cycle is defined as the difference between the duration of a forward movement 80 and a return movement 82 in relation to the sum of the times required for both movements. As already discussed in detail with reference to FIG. 1, a duration 80 of the forward movement can be adjusted via the flow resistance of the fluid path segment with maximum flow resistance used (ie via the diameter and the length of the flow channel), assuming that the spring tension remains constant , Due to the approximately constant restoring force of the spring or the approximately constant flow velocity fluidity prevails in the fluidic device during a forward motion, a continuous, nearly constant fluid flow.

In addition, if the return movement during which the fluidic element 16 is moved from the second position 24 to the first position 22 takes only a short time, it is possible to obtain a fluidic device in which an approximately constant fluid flow prevails. This can be achieved by the flow resistance of the liquid channel 18 of the fluidic element 16 being low, while the flow resistance of the fluid path segment having the maximum flow resistance (fluid path segment 10b) is comparatively high.

Due to both properties, the fluidic system can be operated in a clocked manner so that a quasi-continuous fluid flow can be realized. For example, for medical applications, when using the fluidic system as a pump, it is often necessary for a delivery stroke or forward movement of the fluidic element to occur at least every ten seconds. The return movement of the fluidic element is very short compared to the delivery stroke due to the low flow resistance of the fluidic element with the fluid channel. By varying the bore diameter and thus the flow resistance of the channel, a continuous pumping current can thus be set for a desired delivery rate (= pumping frequency). This also has positive effects on the electrical efficiency of the drive device required for driving the fluidic device described in FIG. 1.

In the dimensioning described above, for example, results in the time course of the current required for the operation of a magnet current 90, which generates the magnetic field, which causes the retrieval of the fluid element 16. In a short return movement is therefore only a small time a current in any existing To feed coil or other electrical device, since during the subsequent movement in the flow direction no electrical power is supplied. Due to the very long compared to the return movement of the fluidic element in the flow direction so a fluid diksystem is generated with an overall positive duty cycle. This has an extremely favorable effect on the overall electrical efficiency of the fluidic system.

10 shows an exemplary embodiment of a fluidic system that includes a non-contact driveable fluidic device 100 and a drive device 110. The fluidic device 100 is, for example, the fluidic device described with reference to FIG. 1. The fluidic system further includes the drive device 110, which is configured to move the fluidic element 16 from the second position 24 to the first position 22. In the state of the fluidic device 100 shown by way of example in FIG. 10, the fluidic element 16 is located at the first position 22, ie immediately at the beginning of a delivery stroke. The fluidic device shown in FIG. 10 merely serves to illustrate the interaction between the fluidic device and the drive device 110, so that a further discussion of the fluidic device 100 shown only schematically at this point in favor of a thorough discussion of the drive device 110 is dispensed with.

The drive device 110 and the fluidic device 100 are, as can be seen in FIG. 10, configured in such a way that both are constructed separately from each other and reversibly coupled to one another. In the exemplary embodiment shown in FIG. 10, the drive device 110 consists, for example, of two collapsible halves 112a and 112b which, when folded together, form an internal volume which corresponds to the volume of the fluidic device 110, so that this can also be completely introduced into the drive device 110. The drive device is designed to move the fluidic element 16 from the second position 24 to the first position 22. This is achieved in the embodiment shown in FIG. 10 by a schematically illustrated coil 114 which generates a magnetic field within the fluidic device 100, by means of which the fluidic element 16 is moved from the second position 24 into the first position 22. At the same time, the spring 14 is pretensioned so that the forward movement of the fluidic element in the fluidic device 100 begins by switching off the current flowing through the coil. As shown in FIG. 10, the fluidic device 100 and the drive device 110 can be coupled to each other in any reversible manner. The more expensive drive device only needs to be manufactured or purchased once. By means of a drive device, an arbitrary number of fluidic devices can be successively operated. Complete sterility using sterilized fluidic devices can be readily ensured by the fluidic system as illustrated in FIG. 10.

The coil 114 shown schematically in FIG. 10 for generating a magnetic field as a drive or as a cause for the restoring force acting on the fluidic element 16 is only one example of a very wide variety of implementations. Any other restoring force applying drive devices may be used. This may be, for example, an electrostatic force exerted on the fluidic element 16 by electrodes disposed at the position of the coil 114. Further, with sufficient mass of the fluidic element 16, a restoring force or force causing the fluidic element 16 to move from the second position 24 to the first position 22 may also be the inertial force. To achieve this, it is possible to move the drive device with high acceleration in the flow direction 6, so that by the inertia of the fluidic 16 this in the first position 22 is moved, from which a renewed movement in the flow direction can take place.

It may also be necessary to check if the fluidic device is functioning as desired or if it is operating at the desired delivery rate. The structure of the fluidic system described in FIG. 10 makes it possible in a simple manner to integrate a detection device into the drive device, which makes it possible to detect the deflection or movement of the fluidic element 16. FIGS. 11 to 13 schematically describe various possibilities for carrying out such a detection.

In FIG. 11, a detection device 116 is formed by an additional coil 118 and an evaluation device 120 connected to the coil, which surrounds the path covered by the fluid element 16 along the fluid path. The at least partially made of a magnetizable or electrically conductive material fluid element 16 induces a voltage in the coil 118 during its movement or changes the inductance of the coil 118. The inductance or voltage change is determined by the evaluation device 120, which also due to a theoretical model or a pre-performed calibration, the position or movement speed of the fluidic element 16, based on the measured quantities, can determine. Thus, it is possible in a simple manner to monitor the delivery rate or the desired operation of the fluidic device 100 and optionally, for example by controlling the coil current of the coil 114, to intervene to correct the fluidic system when used as a pump, for example, to operate too slowly ,

In addition, to close due to an inductance change or an induced voltage on the movement of the piston, moreover, an additional coil 118 is not necessarily required. Rather, the inductance Change or voltage change to the coil 114, which generates the restoring force are read out directly, so as to be able to dispense with the use of an additional coil 118 if necessary.

FIG. 12 shows a further example of how a detection device 116 can be configured which determines a position of the fluidic element 16. In the embodiment shown in FIG. 12, the detection device 116 consists of an electrode arrangement consisting of the electrodes 122a and 122b, which form a capacitance, which in turn is detected by a capacitance measuring device located within an evaluation device 120. When the fluidic element 16 moves into the space between the electrodes 122a and 122b during a movement in the flow direction, the capacitance measured between the electrodes changes. This effect can additionally be influenced by the fact that the fluidic element 16 at least partially consists of a dielectric with a high dielectric constant. From the measured capacitance between the electrodes 122a and 122b, a suitable evaluation device can close the position of the fluidic element 16, so that the operation of the fluidic device can be monitored in this way.

FIG. 13 shows a further exemplary embodiment of a detection device 116, which comprises one or more light sources 130 and a spatially resolving light sensor arrangement 132. The light sensor arrangement 132 is connected to the evaluation device 120 so that a change in intensity that results on the light sensor arrangement 132 when the fluid element 16 is moved into the sensitive area of the light sensor arrangement 132 can be used by the evaluation unit 120 to determine the current one Position of the fluidic element 16 and the piston 16 to determine. In addition to the detection options discussed with reference to FIGS. 10 to 13 for a determination of the piston position or the piston speed and for the flow rate calculation and monitoring, further measures are conceivable which serve to determine the position of the piston.

For example, a small magnetic field can be generated within the yoke via a small coil additionally mounted on the yoke. By means of another small detection coil on the yoke, the changing magnetic field induces a voltage. This voltage Ui _n d is dependent inter alia on the magnetic resistance of the magnetic circuit. This magnetic resistance, in turn, depends on, among other things, the position of the piston. In this way, could also monitor whether the piston has driven the entire hub and whether he z. B. got stuck. An electronic evaluation unit can be used to calculate the piston speed at any time and to count the number of movements in the flow direction. From this it is possible to calculate directly the amount of fluid that has flowed through the fluidic device.

In addition, in the embodiment shown in FIG. 13, the piston or the material of the piston can be suitably changed in order to simplify the optical detection of the surface of the piston. For this purpose, for example, markings with strong light-dark contrasts can be attached to the outer diameter of the fluidic element 16. In addition, the degree of reflection or the degree of absorption of the fluidic element can be influenced by suitable choice of the material.

Although primarily motivated by medical applications in the preceding paragraphs, the fluidic device according to the invention or the fluidic system according to the invention can be used in many other technical fields. For example, they are suitable for chemically corrosive or dangerous (explosive, toxic) liquids because the actual drive device is physically separate from the fluidic device. This minimizes the possibility of leaks and ensures maximum safety.

The materials used for the fluidic element can be freely adapted to the required conditions within wide limits. If, for example, a magnetic drive is to be used, the fluidic element is at least partially made of magnetizable material, for example of ferromagnetic or paramagnetic material. For an electrostatic drive electrically conductive materials could be used. In addition, the fluidic element may be partially formed of dielectric materials if required to detect the position of the fluidic element 16 along the fluidic path or increase detection accuracy.

Although in the embodiments discussed above, the restoring force, that is, the force that moves the fluidic element 16 during the delivery stroke, is generated by a mechanical spring, this type of force generation is not the only one possible. For example, by a second coil, similar to the case of the return stroke, the force which moves the fluidic element 16 can also be generated in the delivery stroke, that is to say during the movement from the first position 22 to the second position 24.

The fluidic device housing 8 may be made of a variety of materials. For example, come thermally moldable plastics or chemically resistant materials into consideration. If necessary, it should be ensured that the electrostatic forces or the electromagnetic fields which may be required to drive the fluidic element 16 can penetrate into the fluidic device housing so that they can act on their force acting on the fluidic element 16.

Claims

claims

1. Fluidic device with a in a flow direction (6) from a Fluidikvorrichtungseingang (2) to a Fluidikvorrichtungsausgang (4) extending Flu- idweg, comprising the following features:

a fluidic element (16) which is movable along a fluid path between a first position (22) and a second position (24) located behind the first position (22) in the flow direction (6) and has a throughflow opening (18); and

a Fluidikvorrichtungsge- housing (8) enclosing the fluid path, wherein

the fluidic element (16) and the fluidic device housing (8) are designed such that the fluidic element is movable from the second position (24) to the first position (22) by a non-contact drive.

2. Fluidic device according to claim 1, wherein a flow resistance of the flow opening at a movement of the fluidic element from the first (22) to the second (24) position is greater than a flow resistance between the fluidic element and the Fluidikvorrichtungsausgang (4).

3. Fluidic device according to claim 1 or 2, wherein a flow resistance of the flow opening at a movement of the fluidic element from the second (24) to the first (22) position is smaller than a flow resistance between the fluidic element and the Fluidikvorrichtungseingang (4).

4. fluidic device according to one of the preceding claims, wherein the flow opening (18) at a movement of the fluidic element (16) from the first (22) to the second (24) position, a first flow resistance, and a movement of the fluidic element (16) from the second (24) to the first (22) position second flow resistance, which is different from the first flow resistance.

5. Fluidic device according to one of the preceding claims, in which the fluidic element (16) is a cylindrical body provided with an axial bore as a throughflow opening (18); and

in which the fluidic device housing (8) forms a volume between the first (22) and the second position (24) that is fluidly close to the outer diameter of the fluidic element (16).

6. Fluidic device according to one of claims 4 to 5, wherein a flow resistance from the Fluidikvor- direction input (2) to the fluidic element (16) or from the fluidic element (16) to the Fluidikvorrichtung- sausgang (4) is greater than the second flow resistance ,

7. Fluidic device according to one of the preceding claims, wherein a cross section of the flow opening (18) of the fluidic element (16) is greater than the minimum cross section of the fluid path between the first position (22) and the Fluidikvorrichtungsein- gang (2) or between the second Position (24) and the fluidic device outlet (4).

8. fluidic device according to claim 4 to 7, wherein the first flow resistance is greater than the second flow resistance.

9. Fluidic device according to one of the preceding claims, wherein the fluidic element (16) is a valve (20), which prevents a flow through the flow opening (18) against the flow direction.

10. Fluidic device according to one of the preceding claims, with the following additional feature:

a check valve (12) between the Fluidikele- element (16) and the Fluidikvorrichtungseingang (2), which prevents a liquid flow against the flow direction (6).

11. Fluidic device according to one of claims 9 or 10, wherein the valve (20) and / or the non-return valve (12) comprises a flap lid valve, a cross-diaphragm valve or a spring-loaded element for closing the flow opening (18).

12. Fluidic device according to one of claims 9 to 11, wherein the valve (20) and / or the check valve

(12) is mechanically biased, so that a force required to open the valve in the flow direction is higher than in the non-biased state.

13. Fluidic device according to claim 12, wherein the valve (20) and / or the check valve (12) by a mechanical element (70; 72a, 72b) is biased, which is shaped such that the valve and / or the check valve ( 12) in the prestressed state seals.

14. Fluidic device according to claim 12 or 13, wherein the valve (20) and / or the check valve (12) by means of a biasing spring (60) counter to the flow direction (6) is acted upon with a force.

15. Fluidic device according to one of claims 11 to 14, wherein the valve is biased such that the force required to open the valve (20) is greater than a force caused by the fluid flowing through the Fluidikvorrich- device force on the valve ( 20), so that upon movement of the fluid element (16) in the flow direction, the valve (20) is closed.

16. A fluidic device according to claim 15, wherein the valve is biased such that a dynamic pressure caused by the fluid exerts a force on the valve (20) is greater than the force required to open the valve (20) force when the fluidi - Kelement (16) from the second (24) is moved to the first (22) position.

17. Fluidic device according to claim 10, wherein the check valve is mechanically coupled to a magnetizable carrier, so that the check valve via the carrier (80 a) can be acted upon with a force.

18. Fluidic device according to one of the preceding claims, with the following additional feature:

a restoring device (14) in order to exert on the fluidic element (16) a restoring force acting in the flow direction (6) so that the fluidic element (16) is moved from the first (22) to the second position (24).

19. Fluidic device according to claim 18, wherein the restoring device (14) is a spring.

20. Fluidic device according to one of the preceding claims, wherein the fluidic device housing (8) is designed such that the fluid path in Strö- mung direction (6) before the first position (22) has a smaller cross-section than between the first (22) and the second position (24).

21. fluidic device comprises according to one of the preceding claims, wherein the Fluidikvorrichtungsgehäuse (8) is formed such that the Fl uidweg ^'in the direction of flow currents (6) to the second position (24) has a smaller cross section than between the ERS th ( 22) and the second position (24).

22. fluidic device according to one of the preceding claims, wherein the fluidic element (16) located in the flow direction in front of a sealing region (16a) lent Äntriebsbereich (16b), wherein the sealing region (16a) fluidly sealed with the Fluidikvorrichtungsgehäuse (8).

23. Fluidic device according to claim 22, wherein the drive region (16b) has a different cross section than the sealing region (16a).

24. Fluidic device according to claim 22 or 23, wherein the drive region (16b) has a flow direction through the drive region extending fluid channel (50a).

25. Fluidic device according to one of the preceding claims, wherein the fluidic device housing (8) has one or more yokes or Pohlschuhe for guiding magnetic fields.

26. Fluidic device according to one of the preceding claims, in which the fluidic element consists at least partially of a magnetizable material.

27. Fluidic device according to claim 26, wherein the magnetizable material is a ferromagnetic or a paramagnetic material.

28. Fluidic device according to claim 26 or 27, wherein the magnetizable material is electrically conductive.

29. Fluidic device according to one of the preceding claims, wherein the fluidic element (16) consists at least partially of dielectric material.

30. Fluidic device according to one of the preceding claims, wherein at least one in the flow direction

(6) part of the fluidic device housing (8) located in front of the first position (22) consists of a non-magnetic material

31. fluidic sensor having a fluid path extending in a flow direction (6) from a fluidic device inlet (2) to a fluidic device outlet (4), having the following features:

a fluidic element (16) movable along the fluid path between a first position (22) and a second position (24) located downstream of the first position (22) in the flow direction (6); and

a Fluidikvorrichtungsge- housing (8) enclosing the fluid path, wherein

the fluidic element (16) and the fluidic device housing (8) are designed such that the fluidic element can be moved from the second position (24) to the first position (22) by a non-contact drive.

32. Fluidic sensor according to claim 31, with the following additional feature: an evaluation device which is configured to detect the presence of the fluidic element at the second (24) position and to calculate a liquid volume during movement of the fluidic element from the first position to the second position through the second element (24) when the fluidic element is present; Fluidic sensor has flowed.

33. Fluidic sensor according to claim 31 or 32, with the following additional feature:

a drive device configured to move the fluidic element (16) from the second (24) to the first position (22).

34. Fluidic system, having the following features:

a fluidic device (100) according to any one of claims 1 to 30 or a fluidic sensor according to one of claims 31 to 33; and

a drive device (110) configured to move the fluidic element (16) or the fluidic sensor from the second (24) to the first position (22).

35. The fluidic system according to claim 34, in which the drive device (110) and the fluidic device (100) or the fluidic sensor are constructed separately and reversibly coupled to one another.

36. The fluidic system according to claim 35, wherein the drive device (110) and the fluidic device (100) or the fluidic sensor are designed such that in a coupled state, the drive device (110) is physically separated from the fluid path.

37. Fluidic system according to one of claims 34 to 36, in which the drive device (110) and the fluidic device (100) or the fluidic sensor are designed such that during a movement of the fluid element (16) the drive device (110) is not in physical contact with a liquid flowing through the fluid path.

38. The fluidic system of claim 34, wherein the drive device further comprises means for generating a magnetic or electric field coupled to the fluidic element such that the fluidic element is from the second (24) is moved to the first position (22).

39. The fluidic system of claim 38, wherein the drive device (110) is configured to generate an electromagnetic field coupled to the carrier (80a).

40. The fluidic system according to claim 38 or 39, wherein the device for generating a magnetic or electrical field (114) comprises one or more coils.

41. A fluidic system according to any one of claims 38 to 340, wherein the means for generating an electric or a magnetic field (114) comprises one or more electrodes to generate an electric field.

42. A fluidic system according to any one of claims 34 to 41, wherein the drive device (110) has one or more yokes or Pohlschuhe for guiding magnetic FeI- countries.

43. The fluidic system according to claim 34, wherein the drive device (110) comprises a movement device, which is configured to accelerate the fluidic device in the flow direction such that the fluidic element of predetermined inertial mass is moved from the second position to the first position.

44. The fluidic system of claim 34, wherein the drive device further comprises a detection device configured to determine a position of the fluidic element.

45. The fluidic system according to claim 44, wherein the detection device (116) comprises a permanent magnet and a magnetic field sensor configured to determine the magnetic field of the permanent magnet.

46. The fluidic system according to claim 45, wherein the detection device (116) further comprises an evaluation device which is designed to close a change in the measured magnetic field to a location and / or a movement of the fluidic element (16).

47. The fluidic system of claim 46, wherein the detection device (120) comprises a coil (118) and a sensor configured to determine inductance induced in the coil and / or an inductance of the coil.

48. The fluidic system according to claim 47, wherein the detection device further comprises an evaluation device (120), which is formed from the voltage detected by the sensor and / or an inductance to a location and / or a movement of the fluidic element (16). close.

49. The fluidic system according to claim 44, wherein the detection device (116) comprises optical detection means (132) adapted to detect the position of the fluidic element (16).

50. The fluidic system according to claim 49, wherein the optical detection device (132) comprises at least one of the following sensor types: light barrier, photodiode line, image sensor, camera chip, CDD CMOS sensor.

51. The fluidic system according to claim 44, wherein the detection device (116) comprises an electrode assembly (122a, 122b) and a capacitance measuring device configured to determine the capacitance of the electrode assembly 122a, 122b).

52. The fluidic system according to claim 51, wherein the detection device (116) further comprises an evaluation device (120), which is designed to close from the determined capacity to a location and / or a movement of the fluidic element (16).

53. The fluidic system of claim 44, wherein the detection device (116) is configured to detect when the fluidic element (16) is at the first (22) or second (24) position and to control the drive device such that the fluidic element (16) is moved from the second (24) to the first (22) position when in the second position.

54. The fluidic system according to claim 53, further comprising an evaluation device for evaluating signals from the detection device (116) and / or the drive device (110) in order to determine from a number of movements from the second (24) to the first (22 ) To close position on a liquid volume flowing through the fluidic device.