CN104245561B - Zero waste dosing method and apparatus for filling liquid containers - Google Patents

Abstract

A zero-waste dosing method for filling a container (22) with a liquid uses at least a volumetric pump (12) with a rotor and a stator at a delivery station (9) of the liquid product, the volumetric pump (12) being connected to a tank (11) containing the liquid to be filled into the container (22).

Description

Zero waste dosing method and apparatus for filling liquid containers

technical field

The present invention relates to a method for obtaining a zero-waste production of containers containing measured quantities of liquids or mixtures of liquids. The invention also relates to a dosing device operating according to said method and to a machine using this device. In particular, the present invention relates to the precise filling of said measured quantities of liquids or mixtures of liquids into containers.

Background technique

It is known that when filling a container with a defined liquid or liquid mixture, there are different tolerance levels with respect to the accuracy of the volume of liquid injected into the container.

It is also known that in certain fields of prior art, such as, but not limited to, the field of medicine, the level of tolerance required is always very small.

It is also known that for very expensive liquids, special or specialty liquids, or even dangerous, poisonous, harmful or polluting liquids, the filling tolerances must be limited to extremely low values, depending on the type of liquid being filled, also A coefficient of 1-10‰ can be achieved.

The "liquid" referred to in various places in the specification should be understood as either referring to a liquid substance in the strict sense (that is, a liquid substance that maintains its own volume under ambient temperature and pressure conditions, but tends to deform to adapt to the shape of the container), or can Refers to a gel-like or similar substance (that is, has a certain viscosity so that it can be transferred with suitable equipment).

With the known filling systems, it is not always possible to achieve the above-mentioned precision, and even when it is achieved, it is not possible to maintain said precision continuously and constancy; this always generates waste because the tolerance requirements are not observed.

Not only does this waste result in lower yields and higher costs, it also creates problems in reprocessing the containers to provide the desired liquid content.

Furthermore, for hazardous, toxic, hazardous or polluting liquids, the reprocessing of containers leads to cost issues, safety issues and often contamination issues both to the product and the environment.

In addition, there are liquids that require continuous protection during transfer to avoid, to the extent possible, certain contaminants.

One of the objects of the present invention is therefore to develop a method which at least makes it possible to avoid waste generation in expensive or dangerous, toxic, harmful or polluting liquids, eg for administration to humans, animals or plants.

It goes without saying that the product, in the case of single use, can also be used for scientific and/or industrial applications.

Another object of the present invention is to obtain a device capable of applying the method.

A related object of the invention is to develop a computer program suitable for executing and controlling said method on a machine comprising said means,

Yet another object of the invention is to obtain a machine for filling containers using said means operating according to the method of the invention and managed by the associated computer program.

The applicant designs, tests and implements the present invention to overcome the defects of the prior art and achieve the above and other objectives and beneficial effects.

Contents of the invention

The invention is stated and characterized by the independent claims, while the dependent claims describe other characteristics of the invention or variants of its main inventive idea.

Based on the above objects, the method of the present invention provides that, at the station for delivering the liquid to the precisely filled dosing container, the use of a precise volumetric pump is connected to a tank or other device for containing the liquid to be introduced into said container. appropriate container for the liquid.

Said positive displacement pump is of the type comprising at least one rotor and optionally an associated stator defining a pump chamber which determines stepwise the suction of liquid from an inlet or suction duct to an outlet or delivery duct.

In the field of said volumetric pumps, a delivery start "zero" angular position or point according to the present invention is defined, which is related to the quantitative angular position of at least one rotor, through which "zero" point the amount of liquid delivered can be controlled so that Get the precision dosing you need.

In particular, in pharmaceutical products or products which need to be protected from contaminating substances, the invention preferably uses peristaltic pumps.

However, it is also within the idea of the invention to use positive displacement pumps, such as gear pumps, lobe pumps or variable tank pumps.

In the case of a peristaltic pump, it is usually provided with a rotor on which 1 or more rollers, as the rollers rotate, continuously and progressively block the elastic tube between the rotor and the stator, inside the elastic tube There is liquid for pumping, and the elastic tube acts as a pumping chamber. The continuous and progressive action of the rollers advances the liquid.

Peristaltic pumps are commonly used in processes where it is necessary to protect the components of the pump from contact with the pumped liquid, which, for example in the present invention, may be hazardous, toxic, harmful and contaminating. The elastic tube can be made of different known materials.

In general, positive displacement pumps and especially peristaltic pumps have discrete accuracy under various factors. Said discontinuities are inter alia related to the normal discontinuous operation (or so-called "start and stop") of the pump, where each operation is associated with a single cycle of complete delivery. This discontinuous delivery is determined by the fact that the quantity of liquid delivered during one operating cycle is exactly the quantity required to fill the container (ie deliver the required quantity of liquid).

Various factors that arise during discontinuous delivery of peristaltic pumps include: size and thickness of the elastic tubing; tubing material; size of the pump chamber between one and its preceding rotating blocking roller; downtime; cycles per unit of time Number; properties of the liquid being transported.

The applicant has demonstrated by experiments, especially in the case of a peristaltic pump, that in the case of discontinuous delivery (“start-stop”), the uncertainty in the total amount of liquid delivered can be reduced to very low values, and within the tightest tolerances allowed.

The Applicant has also verified that if the delivery start "zero" point of the rotor is defined relative to the tube, it is possible to control the delivered liquid volume within tight tolerances, even within 2-5‰.

In yet another variant of the invention, applicants have also addressed the need for liquid delivery due to the momentary end of the cycle (after "stop") and the return of the positive displacement pump rotor to the "zero" point at the start of delivery ("start"). Rotation determines the angular displacement of the additional delivery of the problem.

In order to overcome these problems, and to eliminate said transient effects, the applicant has found that it is possible to provide a shut-off valve, preferably but not limited to a three-way valve, or similar or equivalent alternative channel, arranged downstream of the outlet pipe of the positive displacement pump employed. liquid intercepting member.

In one variant, said valve is located very close to the final delivery member cooperating with the container.

When the rotor of the positive displacement pump reaches the desired end-of-delivery angular position ("stop"), the valve shuts off the liquid flow normally to the final container to divert it into a recirculation branch, e.g. Introduce into original tank or suitable container.

The invention can meet the dosage range from 0.01ml to 1000ml, and meet the strict tolerance range of even 2-5‰.

It should be noted that the actuation of the valve in the present invention must take into account the operation of the valve itself as well as the time required so that shut-off can be performed precisely within the tightest tolerances of the desired delivered volume.

It should also be noted that the method and its associated means allow building a database related to product type and other possible factors (such as temperature, component drift, time between a "stop" and a subsequent "start", etc.), so The establishment of the above database includes statistical form and point-by-point form.

This means that in the first delivery, which involves both a new product that has been delivered before, and a new start after a stop, it is already possible to achieve delivery values within the required tolerances , because the database provides the necessary tuning and control parameters.

Using this method and related devices, it is possible to fill several containers at the same time by means of automatic volumetric pumps dedicated to serving the containers, each said pump downstream of said tank is connected to its dedicated three-way valve, without the need of prior art Any individual precalibration.

In the present invention there may be a single delivery station with a separate upstream measurement station for tareing the containers.

In a variant, the delivery station can be connected to, or integrated with, the means for measuring the tare of the container.

However, volumetric pumps may not be able to maintain delivery constant over time due to drift issues that may not be included in the database; the applicant has foreseen this problem and in a variant there is also a separate station downstream of the delivery station for measuring the filling rate. Gross weight of a full container.

Therefore, in an improved variant form of the invention, there is provided the use of a processing system to compare a theoretical or expected amount of a particular liquid to be filled into a container with an actual or true amount of that particular liquid to be filled into the container, so The theoretical or expected values are stored in an appropriate database to which the processor is connected.

The comparison is derived from tare and gross weight measurements after filling.

The invention provides for using the comparison result for closed-loop feedback control of the positive displacement pump.

In particular, if in this comparison the actual amount poured is less than the theoretical amount, the relative angular position of the delivery start "zero" point of the regulating control system is reversed relative to the direction of rotation of the rotor. Vice versa, if the actual amount is greater than the theoretical amount, the relative angular position of the delivery start "zero" point is shifted forward with respect to the direction of rotor rotation.

Let a denote the angular value of the repositioning from the "stop" point to the "zero" or starting point, or the compensation angular displacement employed, according to the following function:

in:

q = number of liquid units per angular unit or fraction of the shifted angular position of the "zero" point;

g=liquid specific gravity;

d = value of the individual difference between the theoretical and real amount of delivered liquid measured in the control measurement.

In an improved variant, at least one or more of the following functions may be incorporated into the algorithm:

t = liquid temperature;

T = ambient temperature;

D = Factors related to component drift.

In certain modes of execution, for the first start of a positive displacement pump after a standstill or product change, the processor can define the volume of each pump according to the type of liquid product to be delivered, thanks to the information in the database to which the dosing delivery point is connected. Individual "zero" points.

In a variant, the invention provides that when an update of the flow rate is required, the "zero" point remains fixed, while the angular position of the end of delivery of the desired volume of liquid changes.

In the idea of the present invention, the control and command system of the delivery cycle can intervene on the "zero" point and the delivery end point at the same time when necessary.

Description of drawings

In the following, a possible preferred implementation will be described in the form of a non-limiting example in conjunction with the accompanying drawings, so as to clearly illustrate the above and other features of the present invention.

Figure 1 is a schematic partial view of a machine for the precise filling of liquids into containers, the machine comprising means operating according to the method of the invention.

Figure 2 is a schematic diagram of an apparatus operating according to the method of the present invention.

FIG. 3 is an enlarged schematic view of partial details of the device shown in FIG. 2 .

Figure 4 is a general flow diagram of one embodiment of the method of the present invention.

To facilitate understanding, the same reference numerals have been used, where possible, for the same general elements in the drawings. It is to be understood that elements and features of one embodiment may be readily incorporated into other embodiments without further elaboration.

detailed description

The example shown in the accompanying drawings is a machine 20 for accurately filling a plurality of containers 22 with a liquid, which has a dosing device 10 ( FIG. 2 ), a first station 24 and a second station 26; 22 works upstream (only for the chronological order) of the filling step for measuring the tare weight of the container 22 ; a second station 26 works downstream of the dosing device 10 for measuring the gross weight of the container 22 after it has been filled.

In a variant, the first station 24 is provided independently and with physical separation upstream of the dosing device 10 , as shown for example in FIG. 1 . In other variants, the first station 24 is associated or integrated with the dosing device 10 .

The machine 20 is also connected to or comprises an electronic information processor 28 or similar processing means or control directing means for at least directing and controlling the dosing device 10 . Said processor 28 may be equipped with an electronic database of pre-stored data according to the type of liquid to be delivered, which database may be implemented with the obtained point-by-point information.

The dosing device 10 is included in the delivery station 19 and is associated with the lower part of the working platform 30 supporting and positioning the container 22 to be filled, or it can be provided independently.

According to a variant of the invention, the machine 20 is provided with means 25 for uniquely identifying each individual container 22 .

The dosing device 10 ( FIG. 2 ) comprises a liquid tank 11 hydraulically connected to one or more positive displacement pumps, in this case a peristaltic pump 12 . In the case shown in this example, four peristaltic pumps 12 are shown, each for precise filling of its associated container 22 . However, since the ratio between pumps and containers is always 1:1, the number of peristaltic pumps 12 can be varied as a function of the containers that need to be filled simultaneously to meet production needs.

Upstream of each peristaltic pump 12 is connected a first inlet branch 14 for liquid, which connects the tank 11 with the inlet or suction pipe of the peristaltic pump 12; each peristaltic pump 12 at the delivery port or outlet downstream Attached is a delivery member 16, such as a precision nozzle, suitable for pouring the required quantity of liquid into the associated container 22 according to known methods.

In the present invention, a three-way valve is provided downstream of each peristaltic pump 12 and is connected to the delivery member 16 . From each three-way valve 13 extends a second recirculation branch 15 which communicates with a tank 11 or other suitable container.

According to instructions received from the processor 28, the three-way valve 13 is adapted to assume at least a first delivery operating state and a second recirculation operating state. The two states are related to the pointwise angular position of the peristaltic pump 12 .

In the first delivery operating state, the three-way valve 13 allows liquid to flow out of the peristaltic pump 12 , through the delivery member 16 and into the container 22 below.

In the second recirculation operating state, the liquid flow from the peristaltic pump 12 is completely intercepted and diverted into the second recirculation branch 15 from where it is reintroduced into the tank 11 .

FIG. 3 is a schematic diagram illustrating how the three-way valve 13 to which one of the peristaltic pumps 12 in FIG. 2 is connected controls fluid delivery.

The peristaltic pump 12 as shown conventionally includes a rotor 42 on which are mounted a plurality of rollers 44 which block appropriate tubes 46 to allow the advancement of liquid from the tank 11 . In a variant, the number of rollers 44 is advantageously between 4-10, preferably between 5-8. In this case, the rotor 42 is set to rotate counterclockwise. The letter "A" designates the theoretical angular position at which delivery of the filling cycle ends ("stop"), while the number "zero" designates the theoretical "zero" angular position at which delivery begins ("start").

In fact, the angle of rotation can vary from a few degrees to one or more angles of rotation, depending on the amount of liquid that needs to be delivered.

At the end of one delivery cycle (position of point "A" - stop) and before another cycle begins, the peristaltic pump 12 according to the invention must return the angular position of the rotor 42 to the "zero" point - where delivery begins, From there, the rotation to be imparted to the rotor 42 is again determined in order to deliver the required liquid volume.

The rotor 42 is driven by a power unit, in this example a stepper motor 48 to which a position sensor or encoder 50 is connected, which is controlled in position. Processor 28 directs the operation of stepper motor 48 whose instructions are also a function of signals received from position sensor or encoder 50 .

The three-way valve 13 includes an actuator 17 actuated under the control of a processor 28 . The actuator 17 determines the desired positioning of the shut-off member or blocking member (not shown in the figures) inside the three-way valve 13, whereby the three-way valve 13 can selectively assume at least said first delivery operating state or a second second delivery state. Loop running status.

In particular, thanks to the presence of a position sensor or encoder 50, an electronic signal can be transmitted to the processor 28 for identifying when the rotor 42 has reached the angular position "A" at which the filling cycle stops after completing the filling angular displacement. location and moment of time.

When the processor 28 receives a signal indicating that the rotor 42 is close to the angular position "A", the processor 28 issues an activation command to the three-way valve 13, taking into account the delay, so that when the angular position "A" is reached, the three-way valve 13 In the second recirculation operating state.

This causes the pumped liquid volume to be diverted into the second recirculation branch 15 leading to the tank 11 .

Thus, the liquid volume pumped in the angular displacement from the delivery end point "A" (or "stop") to the delivery start angular position "zero" (or "start") is recirculated into the tank 11, The container 22 is not introduced, so the container 22 will only receive the correct amount of liquid associated with the operating cycle.

The second recirculation mode of operation is maintained until the processor 28 receives a signal indicating that the rotor 42 has reached the angular position "zero", at which point it stops, ready to start the next delivery. As a result, the three-way valve 13 returns to the first delivery operating state again.

Arrow FB in FIG. 3 represents an electronic signal entering processor 28 for closed loop feedback control of the operation of peristaltic pump 12 (and optionally actuator 17 ).

The signal shown by the arrow FB includes the theoretical or expected value of the liquid volume that needs to be delivered to the container 22 (such as pre-stored in the database connected to the processor 28) and the real or actual value of the liquid volume delivered to the container 22 in a quantitative duty cycle. Information about the difference comparison between values. Said latter (i.e. true or actual value) is deduced from the individual weight measurements made on each container 22, said measurements taking place upstream and downstream of said filling step, at the first station 24 measuring the skin Weight, the gross weight of each container 22 after filling is measured at the second station 26.

The resulting value of the difference comparison may in turn be compared to a tolerance threshold (eg, a preset value in a database of processor 28, which may vary with the type of liquid to be delivered).

According to the difference comparison result received by the signal of arrow FB, and optionally compared with the tolerance value threshold value, the processor 28 changes the delivery start angle position "zero" according to the requirement by commanding the stepper motor 48, thereby Determines the operation of the peristaltic pump 12 .

In a variant, it is possible to determine or adjust at the same time the position at which the delivery of the desired volume of liquid ends and thus the position at which the shut-off valve begins to operate.

The purpose of changing the angular position of the "zero" point and/or delivery end point is to reduce, if not eliminate, the difference between the theoretical volume of fluid to be delivered and the actual volume of fluid delivered during subsequent delivery cycles. This reset shutoff is preferably carried out between one dosing and the next dosing. In other words, the repositioning can be continuously verified one or more times per total filling cycle, with a preset or presettable cadence (ie a fixed number).

A repositioning of the peristaltic pump 12 is initiated in order to optimize the cycle time of the dosing device 10 and to keep the pressure on the product to be dosed as low as possible.

It should be noted that the processor 28 may also intervene when the command signal is activated and the actuator 17 is positioned, in order to eliminate possible drift problems or problems related to temperature variations.

In particular, the sequence of steps of the method in one embodiment of the present invention is shown in the flowchart of FIG. 4 , which is a non-limiting example of the protection scope of the present invention.

In this example, the flowchart provides a first step (block 60 ) which initializes the control system, typically by means of the processor 28 , for example, the processor 28 is loaded with data and information for the duty cycle and for positioning the rotor 42 of the peristaltic pump 12 possible pre-stored data.

Subsequently, a second step (block 62 ) is provided in which, by virtue of the signal from the position sensor or encoder 50 , the rotor 42 reaches the delivery start angular position “zero” of the peristaltic pump 12 .

Then, a third step is provided (block 64 ), in which the processor 28 loads all available information and parameters, such as the necessary quantity and accuracy requirements for the type of liquid product used for dosing.

Subsequently, a fourth step (module 66) is provided, in which the program is executed by the processor 28 to calibrate the peristalsis according to the relevant information of the signal represented by the arrow FB and optionally according to the database taking into account the quantitative product data archives in the dosing Pump 12 Feedback. This process can set and calibrate a specific product, eg delivery end angular position "A", amount of liquid for dosing, accuracy requirements.

After the calibration, a fifth step (block 68 ) is provided in which the three-way valve 13 is activated and positioned in the first delivery operating state by command of the processor 28 .

Next, a sixth step (block 70 ) is provided in which the processor 28 calculates possible new rotation values that the rotor 42 of the peristaltic pump 12 has to perform, based on the signal indicated by the arrow FB.

Obviously, in each new work session, the first filling cycle is not associated with a feedback signal of a specific work session. Thus, in the case of the first filling cycle, the sixth step may also be performed from a statistical database that takes into account the quantitative product-related data archives in the dosing, or may not be performed. Conversely, each subsequent filling cycle after the first cycle can utilize the feedback control of the same working dialog in the sixth step.

Subsequently, a seventh step (block 72 ) is provided in which the processor 28 waits for a transmission signal to start dosing by the peristaltic pump 12 . In a subsequent eighth step (block 74 ), the dosing is effected with the necessary rotation of the rotor 42 of the peristaltic pump 12 until the end-of-delivery angular position “A” is reached. Now, ninth step (block 76 ), the three-way valve 13 is activated, positioning it in the second recirculation state. Finally, in a tenth step (block 78 ), the rotor 42 of the peristaltic pump 12 is moved from the delivery end angular position "A" to the delivery start angular position "zero". Then, as indicated by the arrow, proceeding from block 78 to block 68 , the work cycle is executed again starting from the fifth step, ie repositioning the three-way valve 13 , until the end of the specific work session.

The method of the invention, in its general form as shown in Figure 4, may be coded by software of said computer program product that is loaded directly into a digital computer memory (in this example processor 28) when the computer program product is executed on a computer. part to execute.

Claims (15)

1. A zero-waste dosing method for filling a container (22) with a liquid, which provides that at a liquid product delivery station (19) at least one volumetric pump (12) with a rotor and a stator is used, which is connected to A tank (11) of liquid to be introduced into said container (22) is associated; said method comprises: a step of filling each container (22), wherein the start of delivery of said volumetric pump (12) is defined "zero" The angular position and the delivery end angular position (A) of the desired liquid amount as a function of said "zero" angular position, said "zero" angular position and/or the delivery end angular position (A) of the desired liquid amount is influenced by Control and regulation of the control command for repositioning said "zero" angular position and/or delivery end angular position (A); said method by means of the selection of the liquid delivered downstream of the outlet tube of the volumetric pump (12) A linear shutoff controls the desired volume of fluid delivered by defining the end-of-cycle delivery instant throughout the delivery end angular position (A). 2. The method according to claim 1, characterized in that, after the delivery instant after the end of the cycle, according to the rotation necessary to bring the rotor of the volumetric pump (12) to the "zero" angular position of the delivery start determining an additional delivery angular displacement along which, in the instant when the delivery end angular position (A) is reached under the action of the rotor of the positive displacement pump (12) The flow of the container (22) is shut off to completely divert the flow into the tank (11). 3. The method according to claim 1 or 2, characterized in that the method recognizes when the volumetric pump (12) has reached the delivery end angular position (A) after completing the angular displacement required for filling position and instant, and completely recirculates the liquid volume pumped between said delivery end angular position (A) to said delivery start "zero" angular position into said tank (11). 4. A method according to claim 1 or 2, characterized in that, upstream and downstream of said filling step, each said container (22) is weighed individually in order to calculate the delivery into said container ( 22) and the theoretical or expected value of the liquid volume to be delivered into said container (22) and the real or actual value of the liquid volume delivered into said container (22) difference comparison, and by changing or restoring the delivery start "zero" angular position and/or the delivery end angular position (A) of the desired fluid volume, in a closed loop feedback via a feedback signal containing information relevant to the difference comparison (FB), to regulate the operation of the positive displacement pump (12). 5. Method according to claim 4, characterized in that the selective shut-off of the liquid delivered downstream of the outlet pipe of the volumetric pump (12) is regulated by the feedback signal (FB). 6. The method according to claim 4, characterized in that it comprises the steps of bringing the rotor of the volumetric pump (12) to the delivery start "zero" angular position; providing information on the liquid product to be dosed a step of information and parameters of the type and/or product to be used for dosing; a step of feedback calibration of said volumetric pump (12) based on said feedback signal (FB); a step of initiating the delivery status of said product; Based on said feedback signal (FB), a step of calculating possible new rotation values that must be performed by said positive displacement pump (12); starting the rotor of said positive displacement pump (12) for dosing liquid product until reaching said positive displacement pump (12) the steps of delivering an end angular position (A); once reaching said delivery end angular position (A), immediately initiating the step of recirculating the liquid product state; and, moving the rotor of said volumetric pump (12) from said delivery end The angular position (A) is again moved to the step of the delivery start "zero" angular position. 7. Method according to claim 6, characterized in that said feedback calibration step of said volumetric pump (12) is based on said feedback signal (FB) and on a statistical database. 8. A zero-waste dosing device (10) for filling a container (22) with a liquid, comprising at least a liquid-filled tank (11) hydraulically connected to one or more positive displacement pumps (12), characterized in that At least one of said positive displacement pumps (12) is configured to: define a delivery start "zero" angular position corresponding to the rotor of said positive displacement pump (12) relative to the liquid pumping chamber between the rotor and the stator associated with a predetermined angular position, and defines the delivery end angular position (A) of the desired amount of liquid, and provides an additional delivery displacement independent of filling liquid into said container (22); said dosing device (10) Control, test and command means are connected for adjusting said "zero" angular position and/or said delivery end angular position (A). 9. The dosing device (10) according to claim 8, characterized in that the upstream of the at least one volumetric pump (12) is connected to the first inlet branch pipe (14) of the liquid, and the downstream is connected to the delivery member (16); said first inlet branch (14) connects said tank (11) with the inlet of said volumetric pump (12), said delivery member (16) is adapted to introduce the required amount of liquid into the associated container (22), It is characterized in that, the downstream of said at least one volumetric pump (12) is provided with a liquid intercepting device (13) capable of channel selection; said liquid intercepting device (13) is connected: 14) said delivery member (16) receiving liquid, a second recirculation branch (15) connected to said liquid shut-off device (13) and leading to said tank (11); said liquid shut-off device (13) with Associated with the end of the delivery of the required amount of liquid. 10. The dosing device (10) according to claim 8 or 9, characterized in that the at least one volumetric pump (12) is a peristaltic pump. 11. The dosing device (10) according to claim 9, characterized in that the dosing device (10) is connected to a processing device (28) for adjusting the liquid shut-off device (13), whereby the Said liquid shut-off device (13) can adopt at least a first delivery operating state and a second recirculation operating state, wherein, in said first delivery operating state, said liquid shut-off device (13) allows flow from said volumetric pump (12 ) through the delivery member (16) to fill the container (22); in the second recirculation operating state, the liquid flow from the positive displacement pump (12) is blocked and fully transferred into the second recirculation branch (15) and from there it is reintroduced into the tank (11). 12. The dosing device (10) according to claim 11, characterized in that the theoretical or expected value of the liquid volume to be filled into the container (22) is related to the volume delivered into the The feedback signal (FB) of the difference between the true or actual value of the liquid volume of the container (22) is compared to adjust said liquid shut-off device (13). 13. Machine for precise filling of a plurality of containers (22) with a liquid or liquid mixture, comprising a dosing device (10) according to any one of claims 8-12. 14. The machine according to claim 13, characterized in that it comprises a first station (24) and a second station (26); said first station (24) is at least temporally sequential in the container (22) filling step Upstream of the station for measuring the tare weight of the container (22), the second station (26) works downstream of the dosing device (10) for measuring after filling the container (22) its gross weight in order to calculate the difference using said tare value to determine the amount of liquid actually poured into said container (22); said machine also includes processing means (28) for at least based on pre-stored in a suitable electronic database and point-by-point information from the first station (24) and the second station (26), command and control the dosing device (10), the pre-stored information is the liquid to be delivered type of function. 15. A machine for the precise filling of a plurality of containers (22) with a liquid or a mixture of liquids, comprising a dosing device (10) as claimed in claim 9, 11 or 12, Said machine comprises a first station (24) and a second station (26); said first station (24) works at least chronologically upstream of a filling step of a container (22) for measuring said container (22) ) tare weight, the second station (26) works downstream of the dosing device (10) for measuring the gross weight of the container (22) after filling, in order to use the tare value to calculate the difference , to determine the amount of liquid actually poured into said container (22); said machine also includes processing means (28) for at least based on data pre-stored in a suitable electronic database and from said first station (24) and point-by-point information of said second station (26), directing and controlling said dosing device (10), said pre-stored information being a function of the type of liquid to be delivered; The processing device (28) is configured to regulate the operation of the volumetric pump (12) using a feedback signal (FB) derived from a comparison of the difference between a theoretical or expected value of the liquid volume of (22) and an actual or actual value of the liquid volume delivered into said container (22), wherein said theoretical or expected value is obtained from said first station (24), Said real or actual value is obtained from said second station (26), wherein said processing means (28) are adapted to regulate the operation of said liquid shut-off means (13) via said signal (FB).