ITBO20060276A1 - VOLUMETRIC DOSING DEVICE AND RELATIVE HANDLING DEVICE - Google Patents

Description

Description of industrial invention

Volumetric dosing device and relative handling apparatus

The present invention relates to a volumetric dosing device, in particular a device for dosing determined and precise quantities of liquid, suitable for use in the pharmaceutical, cosmetic and food fields.

The invention also relates to a handling apparatus adapted to actuate the aforesaid metering device and other similar ones.

In the pharmaceutical and food fields, the use of volumetric piston pumps is known, installed on automatic packaging machines for filling containers, such as bottles, vials, syringes, carpules, ampoules and the like, with liquid products with variable viscosity.

In these devices, the piston translates with reciprocating motion inside a dosing cavity or chamber made in a cylindrical hollow tubular body. The piston stroke makes it possible to suck and subsequently deliver a defined volume of liquid, which is a function of the stroke itself and the diameter of the cylinder cavity.

The dosing chamber has inlet and outlet openings connected respectively to a supply duct and a delivery duct for the liquid to be dosed. Shut-off valves are provided externally on said ducts to alternatively close and / or open the latter during operation of the pump.

Some metering devices in place of external valves include switching means, located inside the metering chamber of the cylinder and controlled so as to connect the latter alternatively with the supply and delivery ducts, in phase with the rectilinear movement. of the piston. Such switching means can consist of a rotary valve inserted in the metering chamber, capable of opening and closing the inlet and outlet openings.

Alternatively, metering devices are known in which the switching means are made on the piston itself which, in addition to sliding axially, can rotate around its own longitudinal axis of translation by a predetermined angle, so as to put the metering chamber in communication. alternatively with the supply duct and with the delivery duct.

This piston, commonly referred to as "piston-valve", in fact has a cavity which in the suction phase faces the supply duct to connect the latter with the metering chamber. The suction stroke of the piston causes an increase in the volume of the dosing chamber and consequently the suction of liquid from the supply duct.

At the end of this stroke, the piston-valve is rotated so that the cavity corresponds with the delivery duct, to allow the piston, during the return or metering stroke, to deliver the predefined quantity of fluid.

At the end of the stroke, the piston is returned to the initial angular position and the described dosing cycle can start again.

Generally the devices described above comprise a cylinder open at the top to allow the introduction from above of a piston-valve provided with an upper end protruding from the cylinder, which can be connected to suitable actuation members which provide for its rotation and translation.

One of the major problems to be solved in the design and construction of this type of metering device lies in the evacuation or discharge of the air present inside the cylinder during the initial priming or starting phase of the pump. To completely fill the dosing chamber of the pump with liquid, the air in it must be able to escape. The presence of air inside the pump is unacceptable because it affects regular operation, compromising the accuracy of the dosage.

To solve this problem, known dosing devices in the start-up phase are generally "primed", that is, filled with liquid with manual or semi-automatic procedures, by means of which the air present in the dosing chamber is evacuated.

These procedures, in addition to being long and laborious, involve the dispensing of a considerable quantity of liquid product destined to be discarded from production because it is dispensed in the containers in incorrect doses or because it is excessively mixed with air. In the case of expensive pharmaceuticals, such waste is considered to be disadvantageous. In addition to this, these procedures require the intervention of one or more operators.

In many applications, especially in the pharmaceutical and food fields, it is also required that the dosing devices can be subjected to washing and sterilization operations on site, without the need to disassemble any of their components. These operations, known as CIP / SIP (Cleaning In Place / Sterilising In Place), basically consist of a sequence of phases, which can be carried out automatically or semi-automatically, during which the inside of the dosing devices is crossed by washing fluids at different temperatures and by pressurized steam. In this way, in a relatively short time it is possible to wash and sterilize all the parts that have come into contact with the product.

An essential condition for the correct and valid execution of a CIP / SIP washing and sterilization procedure is that every internal surface of the device that is in contact with the product is conveniently reached and lapped with the necessary flow rate by the washing and sterilization fluids. .

In addition to this, the structure and conformation of the device must guarantee the correct drainage and emptying of these fluids at the end of the cleaning and sterilization cycles, i.e. the absence of points where said fluids can accumulate and stagnate.

The known metering devices are associated with metering / filling machines generally grouped in a variable number, so as to feed a plurality of respective container filling nozzles.

Support frames support the metering devices and, above them, the piston actuation members, said members being housed inside suitable containers.

The actuation members include motors, transmission mechanisms and kinematic mechanisms, sensors, etc. which for reasons of cleanliness and hygiene must be separated from the environment in which the product is packaged.

If the aforesaid dosing units are mounted on a dosing machine operating in an aseptic or sterile environment, it is observed that the dimensions and position of the aforesaid enclosures for containing the actuation members can cause some drawbacks.

The sterility of the product packaging environment is guaranteed, among other things, by the presence of an adequate flow of sterile filtered air, which flows vertically from top to bottom in unidirectional and uniform motion, in particular in correspondence with the of the operating areas, where for example the product is dosed in the containers.

The air flow forms a sterile air front that laps the containers and drags down with it contaminating particles that may be present in the environment. The air flow also prevents these particles from rising from the bottom up and entering the containers, thus contaminating them. The dimensions of the casings that enclose the movement members and above all their elevated position with respect to the dosing devices disturb the unidirectional and uniform flow of air and force the assembly of the dosing devices to be positioned as far as possible from the dosing area.

When this is not possible, for example due to the transversal dimensions of the metering machine, a deviation and alteration of the air flow in the aforesaid metering area occurs.

In addition to this, due to the translation and rotation movements of the pistons of the pump metering devices, particles can be generated which can be entrained by the air flow inside the underlying containers. The presence of mechanical parts and components inside the sterile area entails the need to break sterility in the event of breakdowns or breakages of the aforementioned mechanical parts and components to allow maintenance interventions. This implies long downtimes and high costs to restore, after maintenance, the correct conditions of sterility required.

Metering devices are known in which the piston can be operated at the bottom, its attachment end protruding from the cylinder at the bottom. However, in order to allow the air to escape correctly from the dosing chamber of the cylinder during start-up, the above devices require laborious manual filling procedures and can only be installed in an inclined position.

If the aforesaid devices are to be installed on a packaging machine, their inclined arrangement entails an increase in overall dimensions and therefore considerable structural and constructive limitations, especially in the case of applications in an aseptic / sterile environment.

The known volumetric piston pumps are generally made of stainless steel, a material which is suitable for contact with pharmaceutical and food products and which can undergo washing and sterilization procedures. The use of ceramic materials is also known, thanks to which it is possible to produce components which have close dimensional tolerances and reduced surface roughness values.

Ceramic materials have very high wear resistance and high temperature resistance coefficients and very low thermal expansion coefficients. The aforementioned characteristics make the ceramic materials particularly suitable for the production of high precision piston pumps and designed for CIP / SIP washing and sterilization procedures.

However, ceramic materials have limitations in the mechanical field, as they are substantially fragile and easily subject to breakage, fractures, chipping.

For this reason, the cylinders of the pumps made of ceramic material are coated with a metal jacket, typically of stainless steel. The latter is hot assembled by interference, so as to form a single monolithic body with the ceramic cylinder.

The external metal casing, in addition to protecting the internal ceramic cylinder, allows the pump to be fixed to a support frame and to connect the connections of the suction, delivery and drainage ducts to it.

However, the irremovable and irreversible interference fit between the ceramic cylinder and the steel jacket has some disadvantages.

It is possible, in fact, that due to a non-optimal coupling there are cracks, fissures, interstices of microscopic size but sufficient to allow infiltration and diffusion of liquids, such as products to be dosed, liquids, in the interface area between the ceramic cylinder and the metal jacket. washing and sterilization. In this case, it is not possible to proceed with a correct and complete cleaning, since the cylinder-liner complex cannot be disassembled.

In addition to this, in the event of breakage or wear of the ceramic cylinder, the jacket must also be replaced, with a consequent increase in costs.

An object of the present invention is to improve known volumetric metering devices.

Another object is to provide a device which allows an accurate and precise dosage in a wide range of filling volumes and which allows an efficient and complete venting of the air automatically, in particular during the start-up phase.

A further object is to obtain a metering device in which the piston can be operated at the bottom, so that the relative movement means are arranged below the apparatus itself.

Another object is to provide a dosing device configured and suitable for washing and sterilization operations of the CIP / SIP type.

A further object is to obtain a device which can be completely disassembled, quickly and easily to allow a complete and thorough cleaning of all its components.

In a first aspect of the invention a device is provided for metering quantities of liquid in desired volumes, comprising movable piston means in a cavity of casing means for withdrawing a quantity of liquid from an inlet of said casing means and directing it towards a 'output of said casing means, said piston means being provided with switching means such as to selectively make said cavity communicating with said input or with said output, said switching means being provided with an operating end which can face at least said output in order to with it define an outflow wall such as to inhibit the adhesion of any air bubbles.

Thanks to this aspect of the invention it is possible to obtain a dosing device which allows an efficient and complete automatic venting of the air during the start-up phase. The operative end of the switching means and the outlet of the envelope means coincide, in fact, with the highest point of the internal cavity, ie the point where any air bubbles could collect. Furthermore, the switching means of the piston means comprise a longitudinal recess configured to form an outflow duct with said outlet, the shape and dimensions of which facilitate the spontaneous escape of the air bubbles and avoid their stagnation inside the cavity.

The particularly accurate and precise surface finish of the surfaces of the cavity and of the piston means helps to avoid adhesion of any bubbles. Thanks to the presence of particular longitudinal grooves on the lateral wall of the cavity of the casing means cooperating in operation with the aforementioned switching means of the piston means, the latter can be operated in translation and rotation by movement means placed under the device.

In particular, the movement means are connected to a lower end of the piston means, which protrudes from the cavity of the casing means at the bottom.

In a second aspect of the invention there is provided a device for metering quantities of liquid in desired volumes provided with movable piston means in a cavity of casing means, comprising covering means adapted to removably contain said casing means.

Thanks to this aspect of the invention it is possible to realize a dosing device in which the envelope means, made for example of ceramic material, are contained, protected from possible breakages, fractures, chipping, inside the covering means, in metallic material, for example stainless steel.

In particular, the covering means comprise two liners configured to contain respective upper and lower portions of the envelope means, said liners being removably connected to each other by fastening means. This allows the device to be disassembled quickly, easily and completely, in order to proceed with a correct and thorough cleaning of the individual components of the device. In fact, it is possible to access all the surfaces of said components, making slits, slits, interstices in the interface area between the wrapping means and the liners of the covering means accessible for cleaning.

The possibility of disassembling the covering means from the casing means allows the replacement of the latter in case of breakage, damage or wear.

The suitably configured coating means also make it possible to make the device of the invention suitable for washing and sterilization operations of the CIP / SIP type.

In a third aspect of the invention there is provided a handling apparatus for a device for dosing, comprising first actuation means and second actuation means which can be coupled to a lower end portion of piston means of said device for moving said piston means. in translation and in rotation.

Thanks to this aspect of the invention it is possible to realize a handling apparatus for dosing devices that can be operated from below which can be placed entirely under the aforementioned devices and housed inside a containment volume that can be hermetically separated from the process environment. , for example the sterile dosing environment. In this way, it is possible to intervene easily and quickly on mechanical parts and components of the apparatus for maintenance and / or repair operations, without the need to pass through the process environment, compromising its sterility.

Furthermore, since the handling apparatus is arranged under the dosing devices, it does not disturb a vertical unidirectional air flow that may be present in the process environment, in particular, in correspondence with an overlying operating area, where, for example, the dosage.

Due to the fact that the connections between the handling apparatus and the piston means of the metering devices are also placed below the operating area, any particles or foreign bodies that may be generated by the translation and rotation movements of the means pistons are further dragged downwards by the air flow, without being able to go up and affect the aforementioned operating area.

The invention can be better understood and implemented with reference to the attached drawings, which illustrate an exemplary and non-limiting form thereof, in which:

Figure 1 is a longitudinal section of the volumetric metering device of the invention, showing piston means in a first suction start operating position and, in broken line, in a fourth delivery end operating position;

Figure 2 is a section like that of Figure 1, showing the piston means respectively in one

second operating position at the end of suction and, in line

dashed, in a third starting operating position

delivery;

Figure 3 is an enlarged partial section like that of

Figure 1, showing an operative end of means of

switching of the piston means;

Figure 4 is an enlarged cross section according to a

floor IV-IV of Figure 1;

Figure 5 is a longitudinal section of a variant of the

device of Figure 1, in which the piston means are in

a fifth washing operating position e

sterilization;

Figure 6 is a partial schematic section of means of

movement of the device of Figure 1 associated with a

frame of a packaging machine;

Figure 7 is a partially sectioned front view of the

handling means of Figure 6 in with a plurality of

devices of Figure 1.

With reference to Figures 1 to 4, a

device for dosing quantities of liquid in volumes

desired, comprising piston means 3 movable in one

cavity 4 of casing means 2 for picking up an amount

desired liquid from an inlet 12 of said means ad

casing 2 and direct it towards an outlet 13 of said means A.

casing 2.

The piston means 3 are equipped with switching means 8 such as to selectively make the cavity 4 communicating with the inlet 12 or with the outlet 13 and are provided with an operating end 8a that can face at least said outlet 13 to define a outflow wall such as to inhibit the adhesion and stagnation of any air bubbles, in particular during the start-up or "priming" phase of the device.

The piston means 3 are movable with alternating translation motion between a retracted or internal position and an extended or external position, and movable with an alternating rotational motion, between an intake position, in which the switching means 8 place the cavity 4 communicates with the inlet 12 and a delivery position, in which they connect said cavity 4 with the outlet 13. Ultimately, the piston means 3 are movable between four different operating positions, as explained in detail in operation of the device.

The substantially cylindrical cavity 4 extends longitudinally for the entire length of the casing means 2, comprising a tubular element, which is also substantially cylindrical.

The cavity 4 is composed of a lower chamber 4a and an upper chamber 4b, having different diameters and lengths. In particular, the lower chamber 4a has a larger diameter than that of the upper chamber 4b.

The upper chamber 4b of the internal cavity 4 is in flow connection with a suction duct 30 and with a delivery duct 31 of the liquid product to be dosed, respectively through said inlet 12 and said outlet 13, which consist of respective holes made on the wall tubular of said upper chamber 4b.

The inlet 12 and outlet 13 holes are arranged at the same level or height with reference to a longitudinal axis Z of the device 1, said axis Z coinciding with the direction of translation of the piston means 3. The inlet and outlet holes 12 13 are angularly spaced from each other by an angle comprised between 30 ° and 180 °, for example 120 ° (Figure 4).

The aforesaid holes are also made practically orthogonal to the tubular wall of the upper chamber 4b. The inner wall of the upper chamber 4a has a first groove 9 and a second groove 10, longitudinal, of elongated shape and substantially parallel to the longitudinal axis Z. Said grooves 9, 10 extend towards the lower chamber 4a starting respectively from the inlet 12 and from exit 13.

The piston means 3 substantially consist of an elongated cylindrical body comprising three portions coaxial to the longitudinal axis Z and having different diameters and lengths.

The piston means 3 comprise an upper end portion 7, an intermediate portion 6 and a lower end portion 5. The latter is configured to protrude from the lower chamber 4a of the casing means 2 in order to allow the connection to handling means adapted to transmit the movement to the piston means 3.

The intermediate portion 6 of the piston means 3 is arranged to slide hermetically inside the lower chamber 4a, while the upper portion 7 is configured to slide hermetically in the upper chamber 4b. Therefore the diameter of the intermediate portion 6 is greater than that of the upper portion 7.

The hydraulic seal between the portions 6, 7 of the piston 3 and the corresponding chambers 4a, 4b is achieved thanks to the reduced clearances between the walls of said portions and said chambers, these clearances allowing the sliding without friction of the piston 3, but not the passage of the liquid to be dosed.

The switching means 8 comprise an elongated longitudinal recess, almost parallel to the longitudinal axis Z of the device 1 and made in the upper end portion 7 of the piston 3.

The recess 8 is shaped to selectively abut the first groove 9 or the second groove 10 and put the lower chamber 4a in communication respectively with said inlet 12 or said outlet 13, depending on the angular position of the piston 3.

In particular, said recess 8 comprises, in addition to the aforementioned operating end 8a intended to face said inlet and said outlet 13, a further operating end 8b, configured to convey the liquid into the lower chamber 4a, and an intermediate connection portion 8c of the two operating ends 8a, 8b. Said intermediate portion 8c is substantially straight and of a width almost equal to that of the grooves 9, 10 of the casing means 2 (Figure 3).

The length of the groove 8 is such as to always allow the flow connection between the lower chamber 4a and the first groove 9 or the second groove 10, regardless of the axial position of the piston means 3.

In operation of the device 1, the piston means 3 are moved through four distinct operating conditions in sequence, to withdraw a desired quantity of liquid from an inlet 12 and direct it to the outlet 13.

In a first operating position A, at the beginning of the descent or suction stroke, the piston means 3 are in the retracted suction position, in which the recess 8 is arranged aligned and facing the first groove 9 of the upper chamber 4a and with the operative end 8a facing and almost mating with the inlet 12. The further operative end 8b opens into the lower chamber 4a which is therefore in flow connection with the suction duct 30.

During the descent stroke of the piston means 3, the fluid to be dosed is drawn back into the lower chamber 4a by vacuum. The outlet 13 is sealed by the upper portion 7 of the piston 3.

At the end of the descent stroke, in a second operating position B, in which the piston means 3 are in the extended suction position, the lower chamber 4a is completely filled with fluid and is still in flow connection through the longitudinal recess 8 and the first longitudinal groove 9 with the delivery duct 12. In this way, any air bubbles present inside the chamber 4a can rise along the groove 8 and the groove 9 and come out of the cavity 4.

The piston means 3 are then rotated into a third operating position C, in which the recess 8 is aligned with the second groove 10 with its operating end 8a facing and opening into said groove 10, to connect the lower chamber 4a to the duct 31. During the upward or delivery stroke, the piston means 3 progressively push the fluid out of the lower chamber 4a towards the delivery duct 31. The inlet 12 is sealed by the upper portion 7 of the piston means 3 .

At the end of the upward stroke, the piston means 3 are in a fourth operating position D, that is, in the retracted delivery position. In this fourth operative position D, the recess 8 is arranged facing the second groove 10 with its operative end 8a arranged facing and almost mating with the outlet opening 13. The further operative end 8b opens into the lower chamber 4a to allow similarly to what happens in the first operating position A, any air bubbles present in the chamber 4a come out.

As known, the air present in a liquid contained inside a cavity tends to rise vertically to collect in the upper part of said cavity, due to the joint effect of the lower density of the air with respect to the liquid and of gravity. Since in the first operative position A and in the fourth operative position D of the piston 3 the highest point of the internal cavity 4 corresponds to the inlet 12 and the outlet 13 respectively, any air bubbles present can spontaneously escape from the device 1.

The air outlet is also facilitated by the vertical movement of the piston means 3 which move axially in delivery from the third operating position C to the fourth operating position D and in suction from the first operating position A to the second operating position B. In a variant of the device 1 not shown, the holes of the inlet 12 and of the outlet 13 are oblique to the side wall of the upper chamber 4b. In particular, the axes of said holes are inclined upwards, starting from the internal surface of the upper chamber 4b, by an angle between 1 ° and 30 °. In this way, the inlet 12 and the outlet 13 and the respective intake ducts 30 and delivery 31 have a slope directed towards the inside of the chamber 4 which further facilitates the escape of any air bubbles present therein.

The longitudinal recess 8 and the grooves 9, 10 have respective bottoms having a concave cross section, in particular they consist of portions of cylindrical or ellipsoidal surfaces. In this way, each groove 9, 10 forms, when facing the longitudinal groove 8, a substantially cylindrical liquid passage duct, of circular or elliptical section (Figure 4).

The operating ends 8a, 8b of the recess 8 include, for example, portions of spherical surfaces or portions of double-curved surfaces, shaped in such a way as to connect accurately and precisely the longitudinal recess 8 to the inlet openings 12 and exit 13.

The conformation of the operating ends 8a, 8b, together with the positioning accuracy of the piston means 3 in the different operating positions, avoids the formation of any niches, undercuts, depressions, microcavities in which any air bubbles present in the liquid can adhere and stagnate. , especially during the startup or "priming" phase of the device.

This result is also obtained thanks to the particularly accurate finishing of the surfaces of the casing means 2 and of the piston means 3. In this way the geometric micro-imperfections normally present on the surfaces, and which generally occur in the form of grooves or scratches, of shape, depth and variable direction are so small and limited that they do not constitute a support for the adhesion and / or stagnation of air bubbles.

Therefore, the device of the invention allows the emptying or purging of the air to be carried out automatically and efficiently, a procedure to be carried out necessarily before the start of production.

The volume of liquid dosed is precisely defined, being a function of the dimensions of the chambers 4a, 4b of the cavity 4, of the portions 6, 7 of the piston means 3 and of the stroke of the piston means 3. The variation of the latter allows the dosing device 1 for dosing defined volumes of liquid contained within a range of values.

From the fourth operating position D, the piston means 3 are rotated and returned to the first operating condition A to repeat the dosing cycle.

The casing means 2 and the piston means 3, which are made, for example, of ceramic materials, have low surface roughness values, high wear resistance coefficients and a reduced release of particles and are particularly resistant to high temperatures. with very low coefficients of thermal expansion.

In order to protect the envelope means 2 from blows and impacts which could compromise its integrity and to allow the assembly of the device 1 to support means of a metering machine, covering means 15, 16 are provided which are suitable for covering and containing, in an assembled condition, the casing means 2.

The coating means 15, 16 are made of metallic material, typically stainless steel of the type commonly used for pharmaceutical and / or food applications.

The covering means comprise a lower jacket 15 and an upper jacket 16, removably interconnected by locking means 17. The latter comprise, for example, a threaded ring nut, adapted to meet a shoulder 15c of the lower jacket 15 and screw to a threaded portion 16c of the upper liner 16.

The lower jacket 15 comprises a first housing 15a configured to contain a lower portion of the casing means 2. Said first casing 15a is open at the top to allow the introduction of the casing means 2 and has a lower opening 15b for the passage of the means. piston 3.

The upper liner 16 comprises a second blind housing 16a, arranged to contain an upper portion of the casing means 2 and, partially, the upper end portion 7 of the piston 3, when the latter is in the retracted position.

The upper liner 16 comprises first connecting means 21 and second connecting means 22 adapted to connect respectively the suction duct 30 to the inlet 12 and the delivery duct 31 to the outlet 13.

The suction ducts 30 and delivery 31 comprise known type fittings, which can be connected to rigid and / or flexible pipes and can be removably coupled to said connection means 21, 22, for example by means of threaded connections or of the type commonly known as "Tri -clamp ". The outer jacket 16 comprises an upper attachment portion 16b suitable for fixing the device 1 to support means, for example of a metering machine with which the device 1 can be associated.

A hooking element 18 is also provided, also made of stainless steel fixed to the lower end portion 5 of the piston means 3 to allow the connection of the latter to movement means. With reference to Figure 5, a variant of the volumetric dosing device 1 of the invention is illustrated which is designed for automatic washing and sterilization processes of the CIP / SIP type, i.e. configured to allow suitable washing and sterilization fluids to flow through the cavity internal 4 to wash and sterilize the latter and the piston means 3.

The casing means 2 and the piston means 3 of this variant are identical to those of the device of the embodiment of Figures 1-4.

The coating means 115, 116 comprise a supply opening 25 and a discharge opening 26 arranged respectively for the inlet and outlet of said washing and / or sterilization fluids.

The supply opening 25 is made on the upper jacket 116 and opens into the second housing 116a at the bottom of the latter.

The discharge opening 26 is made on the lower jacket 115 in correspondence with the lower opening 115a.

Connection elements of known type, for example of the "Tri-clamp" type, can be fixed to the supply openings 25 and discharge 26 to connect the device 1 to the pipes and ducts of a washing and sterilization plant or system.

The lower jacket 115 differs from that of the device of Figures 1-4, in that it has a greater longitudinal extension, since in addition to the first housing 115a it comprises an underlying washing chamber 115d connected to said housing.

The washing chamber 115d and the lower chamber 4a of the casing means 2 are capable of containing the upper end portion 7, the intermediate portion 6 and, partially, the lower end portion 5 of the piston means 3, in a fifth operating position E for washing the latter.

The transverse dimensions, i.e. the diameter, of this washing chamber 115d is greater than that of the intermediate portion 6 of the piston means 3 so that contact with the walls is avoided and a suitably sized interspace is created for the passage of fluids. washing and sterilization. In this way, the latter can touch the internal walls of the cavity 4 and the external walls of the piston means 3 which have come into contact with the metered liquid, in carrying out a CIP / SIP type procedure.

To ensure the hydraulic seal between the lower jacket 115 and the piston means 3 and to avoid the escape of fluid and / or steam during the washing / sterilization phase, gasket means 29 are provided. corresponding to the lower opening 15b, under the discharge opening 26 and finding in the fifth operating position E for washing, an extreme portion 118a of the attachment element 118 which partially covers the lower end portion 5 of the piston 3.

Sealing means 27, 28 are interposed between the casing means 2 and the lining means 116, 115 to prevent washing liquids and / or steam from infiltrating and penetrating into the cavity or space formed by the external surfaces of the casing means 2 and coating means 115, 116.

With reference to Figures 6 and 7, there is also provided a handling apparatus 40 adapted to actuate the piston means 3 with translation and rotation motion during operation of the metering device 1.

The aforementioned handling apparatus 40 can be associated with a packaging machine or, in a variant not shown, with a dosage unit separate from the packaging machine, comprising one or more dosage devices 1.

The movement apparatus 40 comprises first actuation means 41, arranged to drive the piston means 3 in translation and second actuation means 42, adapted to rotate the aforesaid piston means 3.

In particular, the aforementioned actuation means 41, 42 act on a single connecting shaft 50, a free end 53 of which is removably connected to the attachment element 18, 118 of the piston means 3.

The first drive means 41 comprise first motor means 43 of the rotary type, consisting for example of a brushless electric motor, connected to said connecting shaft 45 by means of first transmission means 44, 45. The latter are capable of converting motion rotation of the first motor means 43 in a rectilinear translation motion, along a direction of motion X which is almost coincident with the longitudinal axis Z of the device 1.

Said first transmission means 44, 45 comprise, for example, coupling means of the screw-nut type. In particular, the first motor means 43 rotate a screw 44 on which a bush or nut 45 is engaged, which is prevented from rotating and therefore forced to translate along said direction of motion X.

A support flange 46 fixed to the bush 45 rotatably supports the connecting shaft 50 by means of a respective bearing 47, at its lower end 54 opposite the free end 53 The screw 44 is connected to the output shaft of the first motor means 43 by means of motion reduction means 48, comprising for example a pair of cylindrical gears.

Support means 80, 81 are provided fixed to a frame of the machine 100 to support the entire handling apparatus 40.

In a variant not shown, the first motor means 43 can be of the linear type, to move the connecting shaft 50 directly in translation. The second actuation means 42 comprise second motor means 49, also of the rotary type and consisting of for example in a brushless electric motor, configured to rotate said connecting shaft 50, by means of second transmission means 51, 52.

The latter include sleeve means 51 rotatably fixed to a support plate 81 and configured to slidably engage with a splined portion 52 of the connecting shaft 50. The latter may consist of a splined shaft of a known type, for example a splined shaft. splined shaft provided with cylindrical ends 53, 54 for coupling to support bearings 47, 59.

The sleeve means 51, also of a known type, allow the free sliding in translation of the shaft 50 to which they instead transmit a rotation torque when operated by the second motor means 49.

The sleeve means 51 are connected to an output shaft of the second motor means 49 by means of respective motion reduction means comprising, for example, a toothed wheel 65 adapted to engage a cylindrical toothed portion 51a of said sleeve means 51.

The handling apparatus 40 is designed to be inserted and contained inside a containment volume 101, for example of the packaging machine 100, separated from a process environment 102, in which the dosage takes place, for example, by means of a partition wall 104.

As is known, the separation of the environments must be airtight in the case of applications in the pharmaceutical and food fields, in order to preserve the process environment 102, kept in a sterile controlled atmosphere, from contamination of any type, for example microbiological, particulate, etc.

For this purpose, joining means 70 are therefore provided which are suitable for sealing a passage opening 105 made on the separation wall 104 for the passage of said connecting shaft 50.

The joining means 70 comprise first sleeve means 56 inserted in the passage opening 105 and fixed to the wall 104, for slidingly supporting the connecting shaft 50. The first sleeve means 56 have an elongated tubular cylindrical shape.

Second sleeve means 57 are interposed between said first sleeve means 56 and said connecting shaft 50 and are rotatably connected to the latter by respective rolling bearings 59.

The second sleeve means 57, also having an elongated tubular cylindrical shape, are coaxial with the first sleeve means 56 and with the connecting shaft 50 and can slide axially with the latter, since they are free to slide inside the first ones. sleeve means 56. Their rotation is instead prevented by an anti-rotation element 60 which slides in a slot 61 of the first sleeve means 56.

Containment means 55 are provided on the wall 104 to form the seal between the first sleeve means 56 and the opening 105.

Sliding seals 62 are fixed to one end of the first tube 56 to abut the outer cylindrical surface of the second tube 57 and thus form the seal.

The joining means 70 further comprise a connecting element 63 adapted to connect the free end 53 of the connecting shaft 50 with the hooking element 18 of the piston means 3.

A rotating sealing gasket 64 is provided, fixed to said connection element 63 to abut the external cylindrical surface of the second sleeve 57.

Seals 62, 64 ensure separation between the containment volume 101 and the process environment 102.

The handling means 40 can comprise a plurality of actuation means 41 and 42, to actuate respective metering devices 1, as illustrated in Figure 7. Each metering device 1 is therefore actuated by respective first motor means 43 and second motor means. 49 independently.

Alternatively, the second motor means 49 is provided to include a single motor capable of driving the set of metering devices 1. In this case, the second actuation means 42 comprise respective engagement / disengagement means configured to connect or disconnect respective second transmission means 51, 52 from said motor 49, in the case in which the corresponding metering device 1 is respectively to be activated or locked.

It is important to note that the handling apparatus 40 of the invention is completely housed inside the containment volume 101 of the packaging machine, which is hermetically separated from the process environment 102 and accessible independently and separately, for example through side panels. In this way, it is possible to intervene easily and quickly on mechanical parts and components of the apparatus 40, for example for maintenance and / or repair operations, without the need to pass through said environment 102, compromising its sterility.

With particular reference to Figures 6 and 7, it can be seen that the handling apparatus 40 is arranged below the metering devices, to operate the piston means 3 of the device 1 from below. The process environment 102 is subject to a vertical unidirectional air flow, the apparatus 40 does not perturb this air flow, in correspondence with an overlying operative zone, in which the dosage takes place.

In fact, on the upper portion of the device 1 it is not necessary to have any movement member. Since the connection between the piston means 3 and the actuation means 41, 42 is also positioned below the operating area, any particles or pollutants that may be generated by the translation and rotation movements of the piston means 3 are dragged downward from the air flow, without being able to go up and affect the aforementioned operating area.

There are no particular limitations in the positioning of the metering device or devices of the invention inside a metering machine. These devices and related handling means, since they do not disturb, or only very limitedly, the aforementioned unidirectional air flow, can also be arranged in proximity to the operating area, to create, for example, a machine with reduced transverse dimensions, which allows easy accessibility of all operating groups from one side only, front or rear.

The dosing device 1 and the relative handling apparatus 40 are therefore particularly suitable for being associated with a dosing packaging machine, operating in an aseptic and / or sterile atmosphere under unidirectional and uniform air flow, for example a machine placed inside a clean room or a machine equipped with a sealed cabin or isolator.

Claims (81)

CLAIMS 1. Device for metering quantities of liquid in desired volumes, comprising piston means (3) movable in a cavity (4) of casing means (2) for withdrawing a quantity of liquid from an inlet (12) of said casing means (2) and direct it towards an outlet (13) of said casing means (2), said piston means (3) being provided with switching means (8) such as to selectively make said cavity (4) communicating with said inlet (12) or with said outlet (13), said switching means (8) being equipped with an operating end (8a) that can face at least said outlet (13) to define with it an outflow wall such as to inhibit adhesion of any air bubbles. Device according to claim 1, wherein said cavity (4) passes through and extends longitudinally for the entire length of the casing means (2), said cavity (4) comprising a lower chamber (4a) and an upper chamber (4b), superimposed on said lower chamber (4a). 3. Device according to claim 2, in which said chambers (4a, 4b) are substantially cylindrical, said lower chamber (4a) having a diameter greater than that of said upper chamber (4b). 4. Device according to claim 2 or 3, wherein said inlet (12) and said outlet (13) lead into said upper chamber (4b). Device according to one of the preceding claims, wherein said inlet (12) and said outlet (13) are almost at the same level, with reference to a longitudinal axis (Z) of said device (1). Device according to one of the preceding claims, wherein said inlet (12) and said outlet (13) are angularly spaced at an angle of between 30 ° and 180 °. Device according to one of claims 2 to 6, wherein said upper chamber (4a) comprises a first groove (9) and a second groove (10) connected respectively to said inlet (12) and to said outlet (13) and extending towards said lower chamber (4a). 8. Device according to claim 7, when dependent on claim 5, in which said grooves (9, 10) are substantially parallel to said longitudinal axis (Z). Device according to the preceding claim, wherein said piston means (3) comprise a lower end portion (5), an intermediate portion (6 and an upper end portion (7). 10. Device according to claim 9, in which said portions (5, 6, 7) are practically coaxial. 11. Device according to claim 9 or 10, when claim 9 depends on claim 2, wherein said intermediate portion (6) and said upper end portion (7) are adapted to slide hermetically inside said chamber respectively lower (4a) and said upper chamber (4b). Device according to one of claims 9 to 11, wherein said lower end portion (5) can be coupled to movement means adapted to move said piston means (3). Device according to one of claims 9 to 12, when claim 9 depends on claim 2, wherein said piston means (3) are inserted into said cavity (4) such that said lower end portion ( 5) comes out of said lower chamber (4a). 14. Device according to claims 7 and 9, wherein said switching means (8) comprise a longitudinal recess made in said upper end portion (7) and adapted to selectively abut said first groove (9) or said second groove ( 10), to put in communication said lower chamber (4a) respectively with said inlet (12) or said outlet (13). 15. Device according to claim 14, wherein said longitudinal recess (8) is substantially parallel to said grooves (9, 10). 16. Device according to claim 14 or 15, wherein said operative end (8a) comprises a surface portion adapted to connect said recess (8) with at least said outlet (13), in an operative condition (D) in which said end operating mechanism (8a) of the switching means (8) is practically facing said output (13). Device according to one of the preceding claims, in which said casing means (2) and said piston means (3) are made of ceramic material. 18. Device according to one of the preceding claims, comprising covering means (15, 16; 115, 116) adapted to contain said casing means (2). 19. Device according to claim 18, comprising sealing means (27, 28, 29) interposed between said covering means (15, 16; 115, 116) and said casing means (2). 20. Device according to claim 18 or 19, wherein said covering means comprise a lower jacket (15; 115) and an upper jacket (16; 116) removably interconnected by locking means (17). 21. Device according to claim 20, wherein said locking means (17) comprise a threaded ring nut. 22. Device according to claim 20 or 21, wherein said lower jacket (15; 115) comprises a first housing (15a; 115a) adapted to contain at least a lower portion of said casing means (2) and a lower opening ( 15b; 115b) for the passage of said piston means (3). 23. Device according to claims 9 and 22, wherein said lower jacket (15; 115) further comprises a washing chamber (115d) connected to said first housing (115a) and adapted to contain at least said intermediate portion (6) of said piston means (3) in a washing position (E) of the latter. 24. Device according to claim 23, comprising gasket means (29) fixed to said lower jacket (115) at said lower opening (115b) to abut said piston means (3) in said washing position (E). 25. Device according to claim 9 and one of claims 20 to 24, wherein said upper jacket (16; 116) comprises a second housing (16a; 116a) adapted to contain an upper portion of said casing means (2) and partially said upper end portion (7) of the piston means (3). 26. Device according to claim 25, wherein said upper jacket (16; 116) comprises first connecting means (21) and second connecting means (22) to respectively connect a supply duct (30) of liquid to be dosed to said inlet (12) and a delivery duct (31) to said outlet (13). 27. Device according to one of claims 18 to 26, wherein said covering means (115, 116) comprise a supply opening (26) and a discharge opening (25) for the inlet and outlet respectively of washing and / or sterilization fluids of said device (1). 28. Device according to claim 27, when dependent on claim 25 or 26, wherein said supply opening (26) leads into said second housing (116a). 29. Device according to claims 22 and 27, wherein said discharge opening (25) opens into said first housing (115a), at said lower opening (115b). 30. Device according to claim 12, wherein said piston means (3) comprise a coupling element (18; 118) fixed to said lower end portion (5) for removable coupling to said movement means. 31. Device according to one of claims 18 to 30, wherein said covering means (15, 16; 115, 116) are made of stainless steel. 32. Device for metering quantities of liquid in desired volumes provided with piston means (3) movable in a cavity (4) of casing means (2), comprising coating means (15, 16; 115, 116) suitable for containing said envelope means (2). 33. Device according to claim 32, wherein said covering means comprise a lower jacket (15; 115) and an upper jacket (16; 116) removably interconnected by locking means (17). 34. Device according to claim 33, wherein said locking means (17) comprise a threaded ring nut. 35. Device according to one of claims 32 to 34, wherein said piston means (3) comprise a lower end portion (5), an intermediate portion (6) and an upper end portion (7) between them almost coaxial. 36. Device according to one of claims 33 to 35, wherein said lower jacket (15; 115) comprises a first housing (15a; 115a) adapted to contain at least a lower portion of said casing means (2) and an opening lower (15b; 115b) for the passage of said piston means (3). 37. Device according to claims 35 and 36, wherein said lower jacket (115) further comprises a washing chamber (115d) connected to said first housing (115a) and adapted to contain at least said one intermediate portion (6) of said means piston (3) in correspondence with a washing position (E) of the latter. 38. Device according to claim 37, comprising gasket means (29) fixed to said lower jacket (115) at said lower opening (115b) to abut said piston means (3) in said washing position (E). 39. Device according to claims 33 and 35, wherein said upper jacket (16; 116) comprises a second housing (16a; 116a) adapted to contain an upper portion of said casing means (2) and partially an end portion top (7) of the piston means (3). 40. Device according to one of claims 33 to 39, when claim 35 depends on claim 33 or 34, wherein said upper jacket (16; 116) comprises first connecting means (21) and second connecting means (22) for connecting said device (1) to a supply conduit (30) and a delivery conduit (31) respectively. 41. Device according to one of claims 32 to 40, wherein said covering means (115, 116) comprise a supply opening (26) and a discharge opening (25) for the inlet and outlet respectively of washing and / or sterilization fluids of said device (1). 42. Device according to claim 41, when dependent on claim 39, wherein said supply opening (26) leads into said second housing (116a). 43. Device according to claim 41 or 42, when claim 41 depends on claim 36, wherein said discharge opening (25) flows into said first housing (115a) at said lower opening (115b). 44. Device according to one of claims 32 to 43, wherein said piston means (3) are movable in said cavity (4) to withdraw a quantity of liquid from an inlet (12) of said casing means (2) and direct it towards an outlet (13) of said casing means (2), said piston means (3) being provided with switching means (8) such as to selectively make said cavity (4) communicating with said inlet (12) or with said outlet (13), said switching means (8) being provided with an operating end (8a) that can face at least said outlet (13) to define with it an outflow wall such as to inhibit the adhesion of any bubbles of 'air. 45. Device according to claim 44, wherein said cavity (4) passes through and extends longitudinally for the entire length of the casing means (2) and comprises a lower chamber (4a) and an upper chamber (4b), superimposed to said lower chamber (4a). 46. Device according to claim 45, in which said chambers (4a, 4b) are substantially cylindrical, said lower chamber (4a) having a diameter greater than that of said upper chamber (4b). 47. Device according to claim 45 or 46, wherein said inlet (12) and said outlet (13) lead into said upper chamber (4b). 48. Device according to one of claims 44 to 47, wherein said inlet (12) and said outlet (13) are almost at the same level, with reference to a longitudinal axis (Z) of said device (1). 49. Device according to one of claims 44 to 48, wherein said inlet (12) and said outlet (13) are angularly spaced at an angle of between 30 ° and 180 °. 50. Device according to one of claims 45 to 49, when claims 48 and 49 depend on claim 45, wherein said upper chamber (4a) comprises a first longitudinal groove (9) and a second longitudinal groove (10) respectively connected to said inlet (12) and to said outlet (13) and extending towards said lower chamber (4a). 51. Device according to claims 48 and 50, wherein said longitudinal grooves (9, 10) are substantially parallel to said longitudinal axis (Z). 52. Device according to claims 35, 45 and 50, wherein said switching means (8) comprise an elongated recess made in said upper end portion (7) and adapted to selectively abut said first longitudinal groove (9) or said second longitudinal groove (10), to put said lower chamber (4a) in communication with said inlet (12) or said outlet (13) respectively. 53. Device according to claim 52, wherein said recess (8) is substantially parallel to said longitudinal grooves (9, 10). 54. Device according to claim 52 or 53, wherein said operative end (8a) comprises a surface portion adapted to join said recess (8) at least with said outlet (13), in an operative condition (D) in which said end operating mechanism (8a) of the switching means (8) is practically facing said output (13). 55. Device according to claims 35 and 45, wherein said intermediate portion (6) and said upper end portion (7) are able to slide watertight inside said lower chamber (4a) and said chamber, respectively upper (4b). 56. Device according to claim 55, wherein said piston means (3) are inserted in said cavity (4) in such a way that said lower end portion (5) protrudes from said lower chamber (4a). 57. Device according to claim 56, wherein said lower end portion (5) can be coupled to movement means adapted to move said piston means (3). 58. Device according to claim 57, comprising a hooking element (18; 118) fixed to said lower end portion (5) for connection to said movement means. 59. Device according to one of claims 32 to 58, wherein said casing means (2) and said piston means (3) are made of ceramic material. 60. Device according to one of claims 32 to 59, wherein said coating means (15, 16; 115, 116) are made of stainless steel. 61. Device according to one of claims 32 to 60, comprising sealing means (27; 28, 29) interposed between said covering means (15, 16; 115, 116) and said casing means (2). 62. Apparatus for handling a dosing device according to one of claims 1 to 31 or one of claims 32 to 61, comprising first drive means (41) and second drive means (42) removably connectable to an end portion bottom (5) of piston means (3) of said metering device (1) to move said piston means (3) in translation and in rotation. 63. Apparatus according to claim 62, comprising a connecting shaft (50) interposed between said lower end portion (5) and said actuation means (41, 42). 64. Apparatus according to claim 63, wherein said first driving means (41) comprise first motor means (43) connected to said connecting shaft (50) by first transmission means (44, 45). 65. Apparatus according to claim 64, wherein said first motor means (43) comprise a rotary motor, for example an electric motor of the brushless type. 66. Apparatus according to claim 64 or 65, wherein said first transmission means (44, 45) comprise coupling means of the screw-nut type. 67. Apparatus according to one of claims 64 to 66, wherein said first drive means (41) further comprise first motion reduction means (48) interposed between said first motor means (43) and said first transmission means (44 , 45). 68. Apparatus according to claim 64, wherein said first motor means (43) are linear type and are connected to said connecting shaft (50). 69. Apparatus according to one of claims 63 to 69, wherein said second driving means (42) comprise second motor means (49) connected to said connecting shaft (50) by means of second transmission means (51, 52). 70. Apparatus according to claim 69, wherein said second transmission means (51, 52) comprise rotating sleeve means (51) connected to said second motor means (49) and configured to slidably engage with a grooved portion (52) of said connecting shaft (50) to transmit a rotation torque to the latter. 71. Apparatus as claimed in claim 69 or 70, wherein said second drive means (42) comprise second motion reduction means (65, 51a) interposed between said second motor means (49) and said second transmission means (51, 52 ). 72. Apparatus according to one of claims 69 to 71, wherein said second motor means (49) comprise a rotary motor, for example an electric motor of the brushless type. 73. Apparatus according to one of claims 63 to 72, comprising joining means (70) arranged to seal a passage opening (105) of said connecting shaft (50), said passage opening (70) being made on a wall (104) of a containment compartment (101) of said apparatus (40). 74. Apparatus according to claim 73, wherein said joining means (70) comprise first tube means (56) inserted in said passage opening (105) and fixed to said wall (104), said first tube means (56 ) being adapted to slidingly support said connecting shaft (50). 75. Apparatus according to claim 74, wherein said joining means (70) comprise containment means (55) interposed between said first tube means (56) and said wall (104) to seal said opening (105). 76. Apparatus according to claim 74 or 75, wherein said joining means (70) comprise second sleeve means (57) interposed between said first sleeve means (56) and said connecting shaft (50) and rotatably connected thereto 'last. 77. Apparatus according to claim 76, wherein said sleeve means (56, 57) and said connecting shaft (50) are coaxial. 78. Apparatus according to one of claims 74 to 77, wherein said joining means (70) comprise a connecting element (63) adapted to connect an upper end (53) of said connecting shaft (50) with an element hook (18; 118) fixed to said lower end portion (5) of said piston means (13). 79. Apparatus according to claim 78, wherein said joining means (70) comprise further sealing means (62, 64) interposed between said second sleeve means (57) and respectively said first sleeve means (56) and said element connection (63). 80. Apparatus according to one of claims 62 to 79, comprising a plurality of first actuation means (41) and second actuation means (42) for actuating respective devices (1). 81. Packaging machine for dosing liquid in desired volumes into containers, comprising a set of devices for dosing (1), according to one of claims 1 to 33 or according to one of claims 34 to 62, and a handling apparatus (40) of said set of devices (1), according to one of claims 63 to 80.