DE102009023068A1 - Dosing device for supplying e.g. washing liquid to blood sample chamber for analytical tasks for patient, has pistons arranged behind each other in pipe, where fluids flow between pistons and escape out from opening and arrive into chamber - Google Patents

Abstract

The device has pistons (K1-K6) e.g. injection pistons, arranged behind each other in a pipe (1). Volumes of fluids (F1-F5) flowing through a pipe diameter and a piston space are determined. A feeding mechanism displaces one of the pistons for controllably delivering the fluids. A threaded spindle (7) displaceably acts on one of the pistons far from a side opening (3) in the pipe during activation such that other pistons are displaced due to incompressibility of the fluids. The fluids flow between the pistons and escape out from the side opening and arrive into a sample chamber (2).

Description

at the implementation Chemical analysis or diagnostic procedures often occur Task on, different liquids in a defined order, each with a defined volume and flow (flow = volume / time) into a sample chamber respectively, in which they possibly stay for a given time. In the sample chamber reactions take place, from whose course or result a statement can be derived. Sample chamber is also synonymous here for a different destination for the feeder of liquids.

in the During the procedure, usually at the beginning, is the one to be analyzed Substance or the sample from which the diagnosis is to be derived, into To bring sample chamber.

For example may require a diagnostic procedure after inserting a Blood sample into the sample chamber, the one with a reagent or with has several reagents pointwise coated filter paper, through this sample chamber three different washing liquids, a developing fluid and a fixing liquid to lead.

To the passage of all fluids let yourself in the example from local discoloration close the filter paper to certain results.

In the example, the process can be defined as follows: step liquid volume River dwell 1 Washing liquid 1 2 ml 1 ml / min 2 min 2 Washing liquid 2 2 ml 1 ml / min 1 min 3 Washing liquid 3 2 ml 2 ml / min 1 min 4 developer 1.5 ml 0.75 ml / min 3 min 5 fixer 1 ml 2 ml / min 1.5 min

To In the prior art, five storage vessels and several pumps are used to implement this process or other conveyors and valves necessary. This results in an expensive, even large and hardly portable equipment Execution. For the Self-diagnosis of a patient, for quick use in a doctor's office or for outdoor use, z. B. for the purpose of environmental analysis, this is disadvantageous.

It the object of the invention is a metering device, in particular for analytical To specify tasks that are small and very cheap as well as easy to handle is.

• – Das Dosiergerät besteht aus einem beidseitig weitgehend offenen Rohr, in dem sich mehrere Kolben in der Art von Spritzenkolben (dichtend, unter Druck verschiebbar) befinden.
• – Zwischen je zwei Kolben befinden sich die einzusetzenden Flüssigkeiten mit den vorgegebenen Volumina. Ein Volumen ist durch den Durchmesser des Rohres und durch den Abstand der das Volumen einschließenden Kolben sowie deren Form bestimmt. Die Flüssigkeiten sind in der Reihenfolge ihres Einsatzes angeordnet.
• – Das Rohr weist ein seitliches Loch auf, von dem ein Anschluss an die Probenkammer oder an ein anderes Ziel der Flüssigkeitsführung führt. Alle flüssigkeitsbegrenzenden Kolben und Flüssigkeitsvolumina befinden sich im Rohr auf der einen Seite dieses Loches.
• – Eine Vortriebsvorrichtung, die den am weitesten von dem seitlichen Loch entfernten Kolben, Kolben 1, weiter in das Rohr in Richtung der seitlichen Öffnung schieben kann.
• – In einer bevorzugten Ausführung sind die die Flüssigkeiten führenden Elemente des Dosiergerätes und auch weitere Teile wie Probenkammer und Abfallbehälter als single-use-Elemente (Disposables) ausgeführt. Diese Teile oder dieses Teil wird nach der einmaligen Nutzung verworfen.

The solution according to the invention has the following features:

• - The dosing device consists of a tube on both sides largely open, in which several pistons in the manner of syringe plunger (sealing, displaceable under pressure) are.
• - Between each two pistons are the liquids to be used with the specified volumes. A volume is determined by the diameter of the tube and by the distance of the piston enclosing the volume as well as its shape. The liquids are arranged in the order of their use.
• - The tube has a side hole from which a connection leads to the sample chamber or to another destination of the liquid guide. All fluid-limiting pistons and fluid volumes are located in the tube on one side of this hole.
• A propulsion device which can push the piston farthest from the side hole, piston 1, further into the pipe in the direction of the lateral opening.
• - In a preferred embodiment, the liquid-carrying elements of the dosing device and also other parts such as sample chamber and waste container are designed as single-use elements (disposables). These parts or parts will be discarded after single use.

• – Mit der Verschiebung des ersten Kolbens, der von dem Loch am weitesten entfernt ist, in Richtung des Loches werden wegen der Inkompressibilität der Flüssigkeiten auch alle anderen Kolben in Richtung des seitlichen Loches verschoben.
• – Der Kolben, Kolben n, der dem seitlichen Loch am nächsten ist, wird über dies Loch geschoben. Sobald er bei weiterem Schieben das seitliche Loch nicht mehr bedeckt, beginnt die Flüssigkeit, die sich zwischen Kolben n und Kolben n – 1 befindet, durch das seitliche Loch auszutreten und gelangt in die angeschlossene Probenkammer.
• – Durch die Steuerung der Geschwindigkeit der weiteren Verschiebung wird der Fluss bestimmt.
• – Bei fortschreitender Verschiebung beginnt Kolben n – 1 die seitliche Öffnung zu verdecken, das Flüssigkeitsvolumen zwischen Kolben n und Kolben n – 1 ist vollständig in die Probenkammer gelangt (dazu ist es notwendig, den Gegendruck der Probenkammer kleiner zu halten als den Druck, der zur weiteren Bewegung des Kolbens n erforderlich ist, was meist schon durch die Reibungskräfte gegeben ist, wenn die Probenkammer einen freien Auslauf aufweist). Kolben n und Kolben n – 1 liegen nun aneinander an.
• – Wird die Verschiebung der Kolben nun für eine gegebene Zeit gestoppt, so entspricht diese Stoppzeit der Verweilzeit der Flüssigkeit in der Probenkammer.
• – Bei weiterer Verschiebung gibt Kolben n – 1 die seitliche Bohrung frei und die Flüssigkeit, die sich zwischen Kolben n – 1 und Kolben n – 2 befindet, beginnt seitlich auszutreten und gelangt auf diesem Weg in die Probenkammer. Die Geschwindigkeit der Kolbenverschiebung bestimmt den Fluss.
• – Die Fortsetzung der gesteuerten Verschiebung führt zur Realisierung eines gegebenen Ablaufes, gekennzeichnet durch folgende Parameter:

Parameter Wird bestimmt durch Art der Flüssigkeit – Wahl der Flüssigkeit zwischen zwei Kolben – Reihenfolge der Flüssigkeiten Volumen der Flüssigkeit Abstand der Kolben, zudosiertes Füllvolumen Durchfluss Geschwindigkeit der Kolbenbewegung Verweilzeit in der Probenkammer Pausenzeit bis zur nächsten Verschiebung In the application, the following steps take place:

• - With the displacement of the first piston, which is furthest away from the hole, in the direction of the hole, due to the incompressibility of the fluids, all other pistons are also displaced in the direction of the lateral hole.
• - The piston, piston n, which is closest to the side hole, is pushed over this hole. As soon as If, on further pushing, it no longer covers the lateral hole, the liquid between piston n and piston n - 1 begins to leak out through the lateral hole and enters the connected sample chamber.
• By controlling the speed of the further displacement, the flow is determined.
• - As the displacement progresses, piston n - 1 begins to obscure the lateral opening, the volume of fluid between piston n and piston n - 1 is completely immersed in the sample chamber (for this it is necessary to keep the back pressure of the sample chamber smaller than the pressure applied to the sample chamber) further movement of the piston n is required, which is usually already given by the frictional forces when the sample chamber has a free outlet). Piston n and piston n - 1 are now abutting each other.
• - If the displacement of the piston is now stopped for a given time, this stop time corresponds to the residence time of the liquid in the sample chamber.
• - Moving further, piston n - 1 releases the lateral bore, and the fluid between piston n - 1 and piston n - 2 begins to leak out to the side and enters the sample chamber along this path. The speed of the piston displacement determines the flow.
• - The continuation of the controlled displacement leads to the realization of a given sequence, characterized by the following parameters:

parameter Is determined by Type of fluid - Choice of liquid between two pistons - Order of liquids Volume of the liquid Distance of the pistons, metered filling volume flow Speed of piston movement Residence time in the sample chamber Pause time until the next shift

conveniently, the displacement is generated by an electric linear drive, realized z. B. by a hollow shaft stepper motor with threaded spindle, which presses on the piston 1. A linear motor can also be used.

is the drive designed such that it not only on the piston. 1 to press, but also can pull on it, so the dosing device is also in able to re-liquid to suck out of the sample chamber, what z. B. by a change of To press and sucking for intensive mixing in the sample chamber is to be used.

additional directional flow Valves allow it on the return stroke Air from the outside sucked in between two pistons and during the advance this air in the To encourage sample chamber, where the air flow z. B. rinsing processes support can. The pistons used for air intake are preferably those between those before liquid was included.

Instead of Air can also be the sample fluid or another liquid be sucked. Also does not have to be provided for the inlet opening the opening be that leads to the chamber. Furthermore, aspiration can also take place in an existing liquid volume into, with the sucked portion in the following Course led into the sample chamber becomes. Such a procedure may, for. B. in the analysis of blood from Be beneficial after removal in the patient with a Coagulation-preventing liquid mixed must become. In such a volume, the mixture of two liquids arises, a mixing device may be present, such. B. a specially designed stirring fish, that from outside of the tube is moved by a magnetic alternating field. A other design a stirring element may be that a piston has an elastic tongue, contains the magnetic particles and which is moved by an alternating magnetic field, thereby a movement in the volume and so a mixture arises. In the further displacement of the pistons and the associated emptying the projecting tongue can be from a depression in the other piston, this volume is limited to be included. Fit tongue and Deep well together, complete emptying takes place. The magnetic alternating field can by a mechanically moving permanent magnet or through an electrically generated alternating field are generated, wherein the necessary means are outside the tube.

With A switched valve on the side outlet can be used for the return stroke be sucked out of the sample chamber and on the fore stroke when the valve closed, in the pipe above the opening promoted beyond become. This suction function is z. B. in toxic, infectious or highly active substances of advantage.

The Pistons that have completed their function, are longitudinally over the pushed out lateral hole and abut each other. The pistons can then continued in the pipe or fall out of the pipe. In the continuation of the Pistons in the pipe may be beneficial to the diameter of the pipe there, where the pistons continued are going to expand a little, so that the pistons are lighter there move.

When Another drive version is proposed before the pipe first piston (farthest from the side hole) to close and in the space between this tube cap and the first piston a liquid to pump under pressure with a defined, controlled volume flow through a micropump or a small peristaltic pump or a piston pump or a diaphragm pump or a piston diaphragm pump can be done. This pumped liquid acts on the piston and drives him and thus the others Piston defines forward. By controlling the feed pump can trigger the movement of the piston, stopped, in speed regulated and vice versa (when sucking). If wanted, can in this version in the last step, the pumped liquid be guided partially or completely through the sample chamber.

More as a lateral exit and thus the distribution of stockpiled liquids Achieving more than one goal will be accomplished with an embodiment in which an opening for a longer path covered by a piston, which is also due to extended piston or by two or more directly consecutive pistons is reached.

The fill of the tube with the staggered liquids takes place in such a way that all butts on the otherwise for their output provided Tube side are pushed, and then a feed in the direction of lateral opening so far that the separation point between piston 1 and piston 2 over the lateral opening stands. Then promote a positive displacement pump that for the recording between the piston 1 and 2 provided liquid volume in the side opening. The pressure generated causes the displacement of the piston 1 until the target volume is filled. After that, everyone will Piston advanced to the point of separation between piston 2 and piston 3 over the lateral opening and then after switching the outer fluid paths that liquid dosed and pumped under pressure into the side opening, intended for future use should be located between the piston 2 and piston 3.

To the filling can the liquids stored and transported in the pipe. They are trapped sterile. Only with the application they are conveyed out of the pipe.

EXAMPLES

1 shows an arrangement according to the invention. At the pipe 1 is located, connected via the side opening 3 , the sample chamber 2 , The connection 4 between pipe 1 and sample chamber 2 may be solid or be carried out detachable, z. B. by means of a Luer-lock connector. In the pipe 1 Here are 6 pistons K1 to K6, which include 5 fluid volumes F1 to F5. Liquid entering the sample chamber displaces any fluids present in the chamber through the chamber exit 5 to the outside, to a preferably closed bag 18 can be connected as a waste container. The bag has the advantage that it can be filled without having to displace air from it.

A stepper motor 6 with a spindle 7 . 7a and a threaded nut 8th can with appropriate control commands the spindle pressure piece 9 put on the outer surface of the piston K1 and shifts it when continuing the movement. Each control step for the stepper motor shifts the piston by a defined path, for example by 50 microns, twenty drive steps result in the example, a displacement or a piston stroke of 1 mm. The referencing of the spindle position serves as a reference sensor 14 , z. B. executed as a miniature light barrier.

The pipe 1 carries fasteners or holding devices 10 , z. B. ear-shaped tabs with which it has corresponding counterparts 11 on the base plate 12 is attached. This connection is quickly detachable.

The pipe 1 can be an area 13 have, whose diameter is slightly wider than the remaining pipe diameter. The pistons reach this area after fulfilling their function.

The movement of the piston 1 caused by the motor with the spindle is transmitted to all the pistons because of the incompressibility of the fluids, and in the example the piston K6 moves in the direction of the piston lateral opening 3 of the pipe 1 , Once the piston K6 the opening 3 freewheeling fluid F5 flows through the connection in further engine steps in the forward direction 4 into the sample chamber 2 , By the step frequency of the motor, the flow can be controlled, by pause times in the movement, the residence time of the liquid F5 in the sample chamber 2 , As the stroke progresses, the piston K6 remains to the right of the opening 3 stand and in the consequence reaches the piston 5 over the opening 3 and attaches to the piston K6. With further displacement of the pressure piece 9 Both pistons K5 and K6 move to the right until the piston K5 opens 3 releases and then on further forward stroke of the pressure piece 9 the liquid F4 in the sample chamber 2 occurs.

This sequence of movements can be continued with different step frequencies and stop times until the final state is reached. This is characterized in that here the pistons K2 to K6 right of the lateral opening 3 K1 to the left of this and K1 to K2. The transition point between the pistons K1 and K2 is above the opening 3 , In this state, the liquid F1 has been required in the sample chamber. After reaching the final state, the result can be evaluated in the chamber, z. B. by measuring the transparency or by assessing a resulting color. For this, the combination tube 1 and chamber 2 still connected or disconnected. The pipe 1 gets out of the fixtures 10 / 11 removed and discarded as a singleuse part. After inserting another, previously unused tube, a new measurement can start. On the tube, the other components such as chamber 2 and waste containers 18 be connected.

2 shows the arrangement after 1 in the situation that the liquids F6 and F5 have already been conveyed into the chamber and the delivery of the liquid F3 begins.

3 provides the promotion by a positive displacement pump 20 that is from a reservoir 21 the pumped liquid into the pipe 1 before the piston K1 pumps. The pressure of the incompressible pumped liquid leads to the movement of the piston 1 and the piston operatively connected to it. The pump may also be a peristaltic pump, a diaphragm pump or a piston pump or a piston diaphragm pump.

4 shows an embodiment of the invention with two ways in which liquid from the pipe 1 in the sample chamber or in other directions can be conveyed. The long piston K3 covers the second outlet opening 3a First of all for a longer stroke of all pistons. After the beginning of the movement of the piston K1 caused by the drive, here a spindle motor, all the other pistons also move. Piston K4 is via the first outlet opening 3 pushed and the liquid F3 exits through the outlet opening and enters the sample chamber 2 , The piston K3 closes during the movement of the second outlet opening 3a , With the continuation of the drive movement, the piston K3 continues to move, thereby giving the outlet opening 3a free. Then, when the drive movement continues, the liquid F2 passes via the outlet opening 3a out. The opening 3 is closed by the piston above, so that a return of a liquid can not occur. With the continuation of the drive movement of the piston K2 passes through the opening 3a and subsequently the liquid F1 passes over the port 3a out.

5 presents a variant, which allows to suck in liquid from the outside. Between two pistons, here between the pistons K6a and K6 is a lateral connection 3b attached to the pipe, which is a valve 30 having. The valve allows liquid to enter the tube 1 , but prevents by its directional effect, the escape of liquid from the pipe 1 through the connection 3b , At the further unexecuted continuation 31 This connection, for example, a sample container can be connected. With the withdrawal of piston K1, the piston backward movement continues to the piston K6a. Between the two pistons K6a and K6 creates a negative pressure, which leads to a suction at the port 31 leads and sucks a liquid connected there into the space between the two pistons K6a and K6. This space can also contain a liquid before the start of the suction, which then mixes with the sucked liquid. In order to assist the mixing, a magnetic element may be present in the space, which is moved in the manner of a stirring fish by an external alternating magnetic field. During the forward stroke, the valve closes 30 the outlet and the liquid between the pistons 6a and 6 is in the direction of the outlet opening 3 promoted. For the backward stroke, the lifting device, here the spindle 7 , with the piston K1 via an additional coupling or connection 32 be connected so that tensile forces are transferable, z. B. by hooking.

6 introduces a design that allows sample material to be sucked into the sample chamber. The separation point between the two pistons K6 and K6a is above the opening 3 , During the return stroke, K6a is carried along by the drawn piston K1 and a gap with negative pressure is created between the pistons K6a and K6. The negative pressure settles in the sample chamber 2 and allows it, via a directional valve 40 one Sample volume in the sample chamber. to suck. The sucked liquid can flow between the pistons K6a and K6, but this does not have to be the case. It is assumed that the bag is empty here.

7 represents a filling device for the inventive arrangement. Several storage vessels 50a ..d provide the liquids F1 to F4 to be introduced, which are provided by pumps P1 to P4 and valves V1 to V4 for lateral opening 3 can be promoted optionally. Volume flow meters G1 to G4 can complement the arrangement. Also, there may be a measuring device that measures the piston displacement. A propulsion device used for filling drives the pistons into the tube until the transition between piston 1 and piston 2 over the lateral opening 3 stands. After opening the valve V1 and activating the pump P1, the liquid F1 passes between the pistons and pushes the piston 1 away from the lateral opening. When the intended amount of liquid F1 has entered the pipe, the valve V1 closes and the pump P1 is deactivated. In a further step, the propulsion device drives the piston so much further into the tube until the point of separation of the pistons 2 and 3 over the lateral opening 3 located. After opening the valve 2 and activating the pump 2, the liquid F 2 is conveyed under pressure into the space between the pistons 2 and 3, the pistons 1 and 2 now being displaced. By continuing appropriate steps, the filling of the liquids F3 and F4 between the pistons 3 and 4 or 4 and 5 takes place. In the last step, all the pistons are driven so that in the example of the piston 5, the lateral opening 3 covered or already moved a bit beyond them. The filling arrangement can be supplemented by means which surround the lateral opening 3 Rinse to minimize mixing of the liquids. Also, the filling can be done via one or more lateral opening, which are closed after filling. Mention should be made of the following application option Assume that the last liquid F1 to be fed into the chamber serves the titration with color change, F1 is thus the titrant. Then, with the color change occurring, the further movement of the piston K1 can be stopped and the quantity of titrant determined from the movement steps of the piston K1 which have taken place so far in order to be able to use it in the stoichiometric calculations.

Also It should be noted that the application of the solution according to the invention also for other purposes can be done as analytical tasks, eg. B. for therapy, for example for the controlled feeder several liquids one after the other to a patient.

1

pipe

2

sample chamber

3

Lateral opening of the pipe 1 .

3a

Second lateral opening of the pipe 1

3b

Lateral inlet opening of the pipe 1 ,

4

Connection between sample chamber 2 and side opening 3 of the pipe 1

4a

Connection between sample chamber 2 and side opening 3a of the pipe 1

5

Outlet opening of the sample chamber 2

6

Slide drive, for example, a hollow shaft stepper motor with spindle 7 and threaded nut 8th

7

screw of the sliding drive

8th

threaded nut of the sliding drive

9

On pressing the piston K1 Pressure piece of the sliding drive

10

At the pipe 1 attached releasable holding device for the pipe 1

11

At the base plate 12 fixed counterpart of the holding device 10

12

baseplate

13

room in the no longer needed Pistons are pushed, here with extended diameter

14

Reference sensor, initial position of the spindle 7

15

casing

16

Keyboard, Show

17

electronics assembly

K1

piston 1 (plunger)

K2

piston 2

K3

piston 3

K4

piston 4

K5

piston 5

K6

piston 6

K6a

piston 6a

F1

liquid 1

F2

liquid 2

F3

liquid 3

F4

liquid 4

F5

liquid 5

20

displacement pump, z. B. piston or diaphragm pump or peristaltic pump

21

Reservoir for pumped liquid

22

Pumped liquid already through the pump into the pipe 1 has been promoted and has led to the displacement of the piston K1 and with this operatively connected piston

23

Fixed plug, the pipe 1 closes and through which the pipe 24 passes tightly

24

Pipe or hose coming from the pump 20 in the pipe 1 leads

25

Connector, z. B. a f / m luer lock connector

30

Valve on the pipe 1 , depending on the direction of flow

31

external connection on the valve 30

32

clutch or connection between the lifting mechanism and piston 1, the tensile forces transmitted can.

40

Valve for feeding of liquids at the sample chamber, depending on the direction of flow

60

Stepper motor, generally feed device for the pistons during filling of the dosing device

70

Spindle of the stepper motor 60

80

Nut of the spindle drive 60 and 70

Claims (11)

dosing especially for analytical tasks, in which several liquids preferably a sample chamber in chronological succession with a predetermined time profile for flow rate (dV / dt) and residence times supplied become, characterized in that the liquids in the initial state separated outwards and through each other sealing, sliding pistons are located in a tube, which is a lateral opening has, in the initial state from the inside or by a Piston is covered, the volume of each part liquid by the pipe diameter, the piston distance and the piston shape is determined and a controllable drive mechanism present which, when activated, is farthest from the lateral opening Piston is displaced, so with the displacement of this first Piston due to the incompressibility of the fluids all other pistons likewise and over the lateral opening be moved, which successively all the liquids, each one between two pistons, emerge from the side opening and so preferably get into the sample chamber. dosing according to claim 1, characterized in that as a drive mechanism a spindle is used, in particular one of a stepper motor with hollow shaft and spindle attached to this nut, which exerts a shifting force on the first piston. dosing according to claim 2 characterized in that the spindle not only a oppressive but also to exert a pulling force on the first piston in the Location is. dosing according to claim 1, characterized in that as a drive mechanism a controlled positive displacement pump Application finds a liquid transported to the first piston and this liquid pressurized so that the piston is displaced, wherein a relationship between the number of strokes of the positive displacement pump and the piston stroke is given. dosing according to claim 1, characterized in that the tube more than one lateral outlet has and location and distance of these openings with the location and length of Pistons are tuned so that when moving the piston first a liquid from an opening and then other liquids from other openings occur. Dosing device according to claim 1 and claim 3, characterized in that in a backward stroke, with a pulling force on the first piston thereby moved thereby, the distance between two pistons is increased and in the thus enlarged gap by a lateral inlet opening in the wall of the tube 1 a liquid is sucked in, also via a valve which allows the liquid to enter, but prevents their re-emergence during the subsequent forward movement of the pistons. Dosing device according to claim 1 and the following claims, characterized in that the tube 1 , The mounting tabs and the sample chamber and preferably also a attached to this closed waste containers are made in one piece. Dosing device according to claim 1 and claim 3, characterized in that in a backward stroke, with a pulling force on the first piston thereby moved, the distance between two pistons is increased and in the thus enlarged gap through a lateral outlet opening in the wall of the tube 1 Air is sucked in via a valve, which is ejected again through this opening during the subsequent forward stroke, but can not pass outward through the valve but continues to be conveyed in the system, for example into the sample chamber, the air serving as rinsing or separating agent. dosing according to claim 1 and claim 3 characterized in that at a backward stroke, at a pulling force on the first piston moved thereby, the Distance between two pistons is increased and in the thus enlarged gap a negative pressure is generated, which continues in the system and so to Aspirate a liquid over one directional Valve is used, preferably for sucking a liquid into the sample chamber. dosing according to claim 1 and the subsequent claims characterized that is in the liquid between two pistons is at least one element that passes through an external alternating magnetic field is moved, whereby a mixing of the liquid is effected. dosing according to claim 1, characterized in that the dosing device is coupled for filling with storage vessels, positive displacement pumps and valves and a feed device that pushes the pistons into the tube and subsequently about the lateral opening pushes and, if a separation between two pistons is above the lateral opening is, by means of a pump over one of the valves from a storage liquid between the pistons depressed with the pistons, which already delimit liquid, through the pump pressure to be shifted while the other piston through the non-activated feed device are held and, after a volume is filled between two pistons, the previously opened valve is closed is and then activated feed device the next separation point between two pistons over the lateral opening push, then the filling process with the next liquid is continued and repeat these operations until the dispenser is filled appropriately.