ITBO950582A1 - DOSER FOR INFUSION PRODUCTS - Google Patents

Abstract

The metering unit comprises a metering and filling unit 3 located above a line 5 for conveying a succession of molds 10, associated with a filter-paper web 12. The group 3 is equipped with a body 13 conforming at least one metering chamber 14, arranged along an axis longitudinal to the conveying line 5 and adapted to be fed with the infusion products 2, inside which pusher means 17 acts sliding to carry out the transfer of successive doses 11 of the said infusion products 2. The dosing chamber 14 is in communication with a corresponding filling chamber 16, of tubular shape, having an axis perpendicular to the transport line 5, inside which are sliding pressing means 18, driven by reciprocating motion. Means 4 are adapted to control the movement of the group 3 between a raised position and a lowered working position, in which the filling chamber 16 is adapted to feed a respective dose 11 on the filter paper belt 12, in correspondence with a recess 10a of a relative mold 10.

Description

"DOSER FOR PRODUCTS FROM IN BFUS0ION9E5

DESCRIPTION OF THE INVENTION

The present invention is part of the technical sector concerning the production of pods containing infusion products, such as in particular ground coffee, tea and the like.

More specifically, the present invention relates to a dispenser for infusion products, intended for use in automatic machines for the production of the aforementioned pods.

As is known, the use of filter paper pods containing a suitable dose of the aforesaid infusion products has become widespread. These pods are made in particular of two portions of filter paper welded to each other peripherally so as to centrally enclose the product, suitably compressed and shaped, for example in a discoidal shape.

Various automatic machines, operating according to different functional principles, are known for the production of such pods. Machines of this type are illustrated for example in the Applicant's Italian patent application no. B093A000194 and in the US patent no. 4,555,894.

The machines for producing pods of infusion products are generally equipped with a dosing device which fills a series of cavities formed on a filter paper belt with respective metered quantities of the infusion product; the doses of the infusion product are then suitably compressed. The aforementioned filter paper tape is then covered with a second filter paper tape and welded thereto peripherally to the aforementioned cavities, for the definition of the pods.

In the aforementioned patent application No. B093A000194, the metering device provides a disk peripherally presenting pairs of compartments, suitable for being fed with respective doses of product, and rotatable in steps so as to subsequently occupy a position in which it is able to receive at least two doses of this product and a position in which it is able to deposit the aforementioned doses on the filter paper belt, in correspondence with respective recesses.

In the aforementioned US Patent No. 4,555,894, a filling station is provided in which the single doses of product, delivered by a volumetric dispenser, are made to fall through a vertical tube onto the filter paper belt, preformed with the cavities intended for contain such doses. Two poles are associated with the aforesaid tube, maintained at a controlled potential difference, to deionize the product particles and prevent them from settling on the surface of the tube itself.

US Patent No. 4,747,250 discloses an apparatus for filling the cavities of a filter paper web with respective doses of infusion products. This apparatus provides a conveyor and measuring device for the aforementioned products comprising a rotating disk affected by through openings, intended to receive respective doses of product from a feeding system; the lower surface of the aforementioned disc slides in contact with the upper surface of a base plate, which in turn has a through hole, overlying a conveyor of cup devices on which the filter paper web is spread and preformed. The alignment of the openings of the disc, which can be rotated step by step, with the hole in the base plate allows to deposit successive doses of the product on the filter paper belt.

The purpose of the present invention is to provide a dosing device that allows filling a preformed filter paper belt with metered quantities of infusion products to be carried out in a simple and functional manner, in machines for the production of pods containing such products to be infusion.

The cited object is achieved in accordance with what is reported in the claims.

The characteristics of the invention are highlighted below, with particular reference to the accompanying drawing tables, in which:

Fig. 1 shows a front view of the dispenser for infusion products;

- Figures 1b and 1 show the same view of the metering unit, in different operating conditions;

- Fig. 2 shows a longitudinal sectional view of the dispenser in question, according to the plane II-II of Fig. la;

- figs 3a, 3b, 3c and 3d respectively show a portion of the aforementioned longitudinal section view, in successive operating steps;

- figs.4 and 5 show respective cross-sectional views of the metering device, according to the planes IV-IV and V-V of fig.2;

- Fig. 6 illustrates a rear view in vertical section of the metering device, according to a plane parallel to the front view of Fig.

With reference to the aforementioned figures, 1 indicates as a whole the dosing device for infusion products 2, intended for use in an automatic machine for the production of pods containing the aforementioned infusion products.

The dispenser 1 is placed above a conveyor line 5 of a series of molds 10 intended to cooperate in making the pods. The molds 10, arranged in succession one after the other, advance along the line 5 in the direction indicated by the arrow A, carried by conveyor members not shown, driven in step.

The molds 10 are respectively constituted by a plate carrying, on the upper surface, a pair of side-by-side recesses 10a, with a circular profile, forming a lower half of the molding impression of the wafers.

A first ribbon 12 of filter paper is associated with the molds 10, lying on the upper surface of the aforesaid plates, so as to cover both recesses 10a.

The metering unit 1 provides a metering and filling unit, indicated as a whole with 3, equipped with a body 13 which is movable along a vertical axis. The unit 3 is able to be activated by reciprocating motion, between a raised and a lowered position, by means of a crank mechanism 4 (fig. 6)

The crank mechanism 4 essentially provides a rocker arm 40 pivoted in a central position, on a pin 41, to the fixed frame 9 of the machine and adapted to follow a circular cam 42, activated in rotation by motor members not shown.

The rocker arm 40 is articulated, by means of a connecting rod 43, to a stem 44 mounted sliding, along a vertical axis, through a sleeve 9a of the fixed frame 9 and constrained to the aforementioned body 13 of the metering and filling unit 3.

The body 13 forms a pair of cylindrical-shaped dosing chambers 14 for the infusion products 2, arranged side by side along a horizontal axis longitudinal to the conveyor line 5. The dosing chambers 14 are fed by respective channels 15 for the introduction of the products to be infusion 2 and flow into corresponding filling chambers 16, of tubular shape, having a vertical axis. The filling chambers 16 have a circular section corresponding to the profile of the recesses 10a of the molds 10.

Inside each dosing chamber 14 a piston-type pusher member 17 slides, adapted to transfer the infusion products 2 into the corresponding filling chamber 16. The head of the pin 17 shapes a concavity 17a with a cylindrical profile, according to a direction perpendicular to the axis, substantially coinciding with the profile of the horizontal section of the filling chamber 16 (see in particular fig. 5).

Inside each filling chamber 16 there is sliding, in turn, a pressure member 18 involved, on the lower face, by a recess 18a with a circular profile, forming an upper half of the impression for forming the pods.

The metering and filling unit 3 also carries a pair of forming members 6, of a shape substantially equivalent to that of the recesses 10a of the molds 10, intended for the formation of corresponding impressions on the filter paper belt 12, in a station immediately preceding that filling.

The forming members 6, carried by a crosspiece 19, are adapted to be operated by a pair of actuator members 20, for example of the pneumatic type, integral with the body 13.

The stems 21 of the pressing members 18 are connected at the top to an alternative actuation unit, indicated as a whole with 7, constrained to the fixed frame of the machine.

The actuation unit 7 provides a main rocker 22 mounted oscillatable on a central pin 23, with a horizontal axis longitudinal to the transport line 5; the rocker 22 can therefore be oscillated on a plane transversal to the line 5.

The rocker 22 has an auxiliary rocker 25 pivoted near one of its ends, on a relative pin 24, which can be oscillated on the same transversal plane and constrained to a pressure limiting member 26, of the pneumatic type, carried by the same rocker 22; the member 26 is able to exert a constant thrust on the auxiliary rocker 25.

The auxiliary rocker 25 carries a roller 27, freely rotatable, which is in contact with a cam member 28, driven in rotation according to its own axis 29 and able to control the reciprocating movement of oscillation of the main rocker 22. The rocker 22 is constrained in addition to a return spring 30.

The main rocker 22 is articulated to the stems 21 of the pressure members 18 by means of a pivoting member, indicated as a whole with 8. Said pivoting member 8 provides a block 31 centrally pivoted to the rocker 22, on a pin 32, at the opposite end with respect to the cam 28. The block 31 is articulated by means of a pair of connecting rods 33 with respective heads 34 mounted at the top of the stems 21; the rods 21 are axially rotatably coupled to the heads 34, by means of the interposition of rolling bearings 35.

The heads 34 are faced by adjustable abutment organs 48, integral with the fixed frame 9, having a safety function. These abutments 48 are adapted to limit the maximum excursion of the pressure members 18 during the descent phase.

The tilting block 31 has an appendage 36 at the top which is normally elastically clamped between a pair of rollers 37 eccentrically carried by a corresponding pair of toothed wheels 38, in gear with each other, mounted on the fixed frame 9 of the machine.

The toothed wheels 38 are constrained to each other by means of a helical spring 39 fixed in eccentric positions to the toothed wheels 38 themselves. The action of the spring 39 is such as to elastically recall the rollers 37 towards each other.

The stems 21 of the pressing members 18 are guided slidingly through the aforementioned sleeve 9a and are also rotatable with respect to their own axis. The stems 21 carry respective radial arms 45, connected by a connecting rod 46, forming a lever system which is able to be operated by a suitable actuator member, for example a jack 47 (Fig. 4). This lever mechanism is capable of imposing an appropriate oscillation on the pressing members 18 at the same time as the pressing members themselves rise.

The operation of the dispenser is now described starting from the step of dosing the infusion products intended to form the pods. In this phase, the plunger pushers 17 are moved to a rear position inside the dosing chambers 14, so as to allow the infusion products 2 to be introduced through the respective channels 15 (Fig.3a).

During the feeding of the products 2, the descent of the dosing and filling unit 3 is controlled in the lowered position, by the crank mechanism 4, so as to bring the lower end of the filling chambers 16 practically at the level of the molds 10, in order to correspondence of the recesses 10a (fig.3b).

At the same time, the raising of the pressure elements 18 inside the same filling chambers 16 is controlled, by the actuation unit 7, and the descent of the forming elements 6 which form corresponding impressions on the filter paper belt 12, in a station immediately. previous to the filling one (see again fig.3b).

Once the feeding of the foreseen doses of the infusion products 2 is completed, the advancement stroke of the pushers 17 is controlled, which transfer these products into the corresponding filling chambers 16 (Fig.3c). The products 2 fall by gravity into the mold 10, covered by the ribbon 12 of filter paper, formed according to the imprint of the recesses. inside the filling chambers 16, by means of suitable channels 50 made in the body 13, so as to achieve a better settlement of the infusion products 2.

It should be noted that this technique does not cause overpressures inside the filling chambers 16 thanks to the permeability of the filter paper ribbon 12. A further advantage offered by this technique is to replace an inert gas for the gases which normally remain enclosed in the mixture of infusion products.

Furthermore, the dispenser in question is preferably integrated in an apparatus operating in an inert atmosphere, as is apparent from other contemporary patent applications filed today by the Applicant. There is therefore no need to create a protective patina on the surface of the pods.

Subsequently, the descent of the pressing members 18 which compress the infusion products 2 onto the molds 10 is controlled, in the disc-shaped compartments defined between the relative recesses 10a and 18a, so as to realize the doses 11 of the pods (fig.3d).

The value of the pressure exerted by the pressing members 18 is chosen in such a way as to make the pods suitably compact.

At the end of the realization of the doses 11 of the pods, the ascent of the dosage and filling unit 3 to the raised position is commanded by the crank mechanism 4, so as to allow the advancement of the conveyor line 5 of the molds 10.

At the time of the aforesaid ascent, the lever mechanism 45, 46 imposes an appropriate angular rotation on the presser members 18, apt to favor the detachment of the tablet doses from the latter.

The pressing members 18 are driven by reciprocating rectilinear motion, as already mentioned, by the actuation unit 7 equipped with the rocker 22 which is made to oscillate by the rotation of the cam 28; the rocker arm transmits motion to the stems 21 of the pressure members 18 by means of the pivoting member 8 (figs la, 1b).

In fact, the cam 28 acts on the auxiliary rocker 25 which is linked to the main rocker 22 by the pressure limiter 26. In normal operating conditions, this pressure limiter 26 ensures a rigid connection between the auxiliary rocker 25 and the main rocker 22.

However, should an overpressure occur, due in particular to an excess of infusion products introduced into the filling chamber 16 with respect to the prescribed dose, there is an axial thrust on the pressers 18 such as to overcome the elastic reaction of the pressure limiter 26, so that a relative angular movement of the auxiliary rocker 25 is determined with respect to the main rocker 22 (Fig. 1c).

In practice, the stroke of the rocker 22 is reduced by a portion equal to the displacement corresponding to the aforementioned relative angular movement of the auxiliary rocker 25. This obviously allows the value of the compression of the infusion products forming the dose 11 to be suitably limited.

The tilting member 8 has the function of avoiding non-uniformity of thrust on the two pressing members 18, for example due to a non-uniform feeding of the infusion products 2 into the two filling chambers 16. In fact, in normal conditions, i.e. with uniform stresses, the appendix 36 of the tilting block 31 is centered between the rollers 37 and descends vertically during the actuation of the pressers 18 (fig. La).

On the other hand, in the event of an imbalance between the aforesaid stresses transmitted by the pressers 18 to the stems 21, the tilting block 31 obviously tends to rotate angularly, allowing unequal sliding of the pressers 18 (Fig. 1b). The appendix 36 tilts in turn, spreading the rollers 37 in contrast to the elastic reaction of the spring 39.

In this way, in any case pods are produced with a uniform pressure, even in the case of an uneven feeding of the products into the filling chambers 16. During the return stroke of the pressers 18, the spring 39 tends to re-tighten the appendix 36 between the rollers. 37, in a centered position, restoring the verticality of the tilting block 31 and consequently the approach of the same pressers (fig.lc).

The dispenser in question ultimately allows to carry out in a simple and functional way the filling of a preformed filter paper belt with metered quantities of infusion products, in a machine for the production of pods containing said infusion products.

It should be emphasized that the dispenser allows to feed a double ribbon of filter paper at the same time, so as to increase the productivity of the machine in the production of pods. This is achieved by keeping the compression of both doses of the aforementioned pods packaged simultaneously balanced.

Furthermore, any overpressure, determined for example by a dose higher than the foreseen limits, is absorbed by the actuating members of the metering device, in a way, among other things, to avoid damage.

An important prerogative of the proposed solution is given by the constructive and functional simplicity of the organs responsible for dosing the products to be packaged in pods. These parts are also easily accessible for inspection and maintenance operations.

A further important prerogative of the proposed solution is given by the fact that the device allows the shaping of the paper-filter web to be formed simultaneously with the dosage and filling phases of the pods, by the same group that carries out these phases.

It is understood that what above has been described by way of non-limiting example, therefore any constructional variants are intended to fall within the protective scope of the present technical solution, as described above and claimed hereinafter.

Claims (11)

CLAIMS 1) Doser for infusion products, characterized in that it comprises a dosing and filling unit 3 positioned above a line 5 for conveying a succession of molds 10, associated with a filter paper belt 12, and equipped with a body 13 conforming at least one dosing chamber 14, arranged along a longitudinal axis to said transport line 5 and able to be fed with the infusion products 2, inside which pusher means 17 are able to operate the transfer of successive doses 11 of said infusion products 2, and a corresponding filling chamber 16, of tubular shape, having an axis perpendicular to said conveyor line 5 and in communication with said dosing chamber 14, inside which pressure means slide 18; means 4 for controlling the displacement of said dosing and filling unit 3 between a raised position and a lowered working position, in which said filling chamber 16 is adapted to feed a respective dose 11 of said infusion products 2 onto said belt 12 of filter paper, in correspondence with a recess 10a of a relative mold 10; means 7 for the alternative actuation of said pressing means 18. 2) Doser according to claim 1, characterized in that said body 13 forms a pair of cylindrical-shaped dosing chambers 14 for said infusion products 2, arranged side by side along a horizontal axis longitudinal to said transport line 5 and in communication with corresponding filling chambers 16, having a vertical axis. 3) Doser according to claim 2, characterized in that said dosing chambers 14 are fed by respective channels 15 for inlet of said infusion products 2, suitable to be closed by relative piston-type thrusting means 17, mounted sliding inside of the same dosing chambers. 4) Doser according to claim 1, characterized by the fact that said pushing means 17 have a head shaping a concavity 17a with a cylindrical profile, according to a direction perpendicular to the axis of the same pushing means 17, substantially coinciding with the profile of said chamber filling 16. 5) Doser according to claim 1, characterized in that said pressing means 18 have a circular profile recess 18a on the lower face which cooperates with said recess 10a of the mold 10 to produce a molding impression for said dose 11. 6) Doser according to claim 1, characterized by the fact that said means 7 for the alternative actuation of said pressure means 18 foresee a main rocker 22 mounted oscillating on a vertical plane transversal to said transport line 5 and having an auxiliary rocker pivoted 25 which can be oscillated on the same transverse plane and constrained to a pressure limiting member 26, with said auxiliary rocker 25 subject to cam means 28, driven in rotation according to its own axis 29 and able to control the reciprocating movement of oscillation of said main rocker 22 . 7) Doser according to claim 1, characterized in that said actuation means 7 are articulated to a pair of stems 21 of respective pressure means 18, sliding in a corresponding pair of filling chambers 16, by means of a pivoting member 8 adapted to avoid uneven thrust on the respective doses 11 fed into said filling chambers 16. 8) Doser according to claim 7, characterized in that said pivoting member 8 provides a block 31 centrally pivoted to said actuation means 7 and articulated by means of connecting rod 33 to respective heads 34 mounted at the top of said stems 21, with said block 31 having at the top an appendage 36 able to be elastically clamped between a pair of rollers 37 carried eccentrically by a corresponding pair of toothed wheels 38, in reciprocal gear, constrained to each other by means of spring means 39 fixed in eccentric positions to the toothed wheels 38 themselves, so as to elastically recall said rollers 37 towards each other. 9) Doser according to claim 1, characterized by the fact that said metering and filling unit 3 carries forming means 6, of a shape substantially equivalent to that of said recesses 10a of the molds 10, intended for the formation of corresponding impressions on said belt 12 of filter paper, in a station immediately preceding a filling station, with said forming means 6 adapted to be operated by actuator means 20 integral with said body 13. 10) Doser according to claim 1, characterized by the fact that said pressing means 18 are rotatably mounted with respect to their own axis and are associated with a lever mechanism 45, 46 able to be operated by actuator means 47 intended to impose a angular oscillation. 11) Doser according to claim 1, characterized in that said body 13 has channels 50 suitable for introducing an inert gas under pressure into said filling chamber 16, for a better settling of said infusion products 2.