Machine with continuous cycle for the sterilization and filling of drums, and the like

Abstract

 In a machine, preferably with turntable (2), with a plurality of sequential work heads, are carried out automatically and in successive phases the seal control, sterilization and filling of drums for liquid products in general, and, sin particular, for liquid food products, such as drinks and the like.

Description

[0001] The invention concerns a machine with continuous cycle for the sterilization and filling of drums, and the like, in which the incoming drums, conveyed by a motorized belt po­sitioned upstream, are first aligned and automatically ar­ranged with respect to the position of their small filling and drain valves, then engaged in sequential heads in which said small valves are aligned and connected with distri­butors. The distributors are positioned, programmed and automatically driven to open and close in sequence in order to carry out, in each drum and at each head, a pressure-­seal test, a steam sterilization treatment, a drying and discharge of condensations, a filling in pressure of car­bon dioxide (CO₂), a filling in counterpressure with con­trolled discharge of CO₂ of the liquid product to be packed, a final recovery of the residual product comprised in the heads and a washing in CO₂ of said heads.

[0002] Everything takes place in sequential, automatic manner, with the drums in movement, up to their discharge on a con­veyor belt positioned upstream of the machine.

[0003] It is known that many products in the liquid state, and in particular drinks in general, and the like, besides in the most well known packs, like bottles, small bottles, cans, cartons, are packed in drums for distribution and fast, ra­tional use of the drinks in "draught" pouring systems, presently developed and used in many public places, e.g. beer-houses, bars, restaurants etc.

[0004] Said drums, equipped with main door and small filling and drain valves, are recycled, and, at each new filling, must first be washed and rinsed, then, with main door closed, are submitted to filling. These operations are at present carried out by devices controlled and manoeuvred by hand, so that the washed and rinsed drums pass to fil­ling, where operators manually insert the feed mouths in the respective valves.

[0005] At the end of filling, the same operators carry out de­tachment of the manifolds and load and send the drums to the following phases of storage and palletization.

[0006] All this, as is evident, is very expensive, as a con­siderable amount of labour and high working times are in­volved.

[0007] Another particular problem consists in the fact that, at present, in the sequence of the above operations, no steri­lization cycle of the washed drums is provided, and there­fore, before filling and in closing phase of the upper co­ver, they are handled without special sanitary or hygienic conditions, with the serious risk that the liquid products subsequently inserted, especially the liquid food products, may suffer undesired pollution or even infective contamina­tion.

[0008] The object of the present invention is to eliminate the the above problems.

[0009] The invention, as characterized by the claims, solves the problem by means of a machine with continuous cycle for the sterilization and filling of drums, and the like, with which the following results are obtained:
the washed drums are submitted in sequence to a pressure test, a sterilization and filling, in totally automatic and programmed manner, during a continuous cycle which re­ceives the drums from conveyor belts, arriving from washing stations positioned downstream, and discharges them on con­veyor belts positioned downstream, directed to storage or palletization stations.

[0010] Each drum is submitted to automatic controls and to sepa­rate seal check, and, on the basis of the results, the con­tinuation or interruption of its cycle is established auto­matically, independently from the controls and from the characteristics of the other drums.

[0011] The advantages of the machine object of the present inven­tion mainly consist in the fact that, before being filled, the drums are submitted to a pressure seal test to check their physical integrity, and to a sterilization treatment which eliminates all types of pollution and excludes the possibility of infective contamination, or the like.

[0012] Other advantages consist in the fact that the drums are aligned, controlled, treated and filled automatically and in continuous cycle, with a substantial saving of time with respect to the present work cycles; the automation of said cycle also allows to drastically reduce the use of labour.

[0013] The invention is described in more detail below, accor­ding to a preferred construction given only as example and unbinding, with reference to the enclosed drawings, in which:

fig. 1 is a lateral schematic view of the machine as a whole,

fig. 2 is a schematic view in plan of the same machine,

fig. 3 is a schematic cross-section of the central rotating distributor,

fig. 4 is a partial front view of a distributor of one head of the machine,

fig. 5 shows the longitudinal section of one of the distri­butors, and

fig. 6 shows, in detail, a lifting apparatus of the drums, equipped, according to a variant, with a "weighing" control device,

figs. 7 and 8 show respectively the upper and lower con­taining plates for the balances.

[0014] The figures illustrate a machine with continuous cycle for the sterilization and filling of drums, substantially com­posed of a fixed supporting structure (1) on which is posi­tioned a rotating turntable (2) moved by a speed reducer (3) which drives a pinion (4) engaging in a round toothed crown (5).

[0015] On the periphery of the abovementioned rotating turntable (2) are aligned work heads, each composed of a supporting deck (6) supported by a vertical piston (7) and guided by a rear column (8). Each supporting deck (6) is aligned to an upper distributor (9), which in turn comprises the ne­cessary connections (10), connected respectively to air inlets (11 ), CO₂ inlets (12), product inlets (13) and dis­charge inlets (50), present on the surface of a central distributor (14) which rotates, together with the rotating turntable (2), round the fixed central structure (15), in which are obtained the feed and/or discharge channels cor­responding to the abovementioned inlets.

[0016] To each distributor (9) is also coupled another connection (10′) which is connected to a steam distribution manifold (16).

[0017] To the central rotating distributor (14) is coupled an up­per plate (17) on which are radially applied, with possibi­lity of regulation of position and of intervention, some means of contrast (18), e.g. limit microswitches or similar. During rotation, these contacts (18) enter or do not enter into engagement with some push rods (19), also adjustable on the basis of pre-established programs, modifiable to suit needs.

[0018] Each distributor (9) is divided into two blocks (20) and (21) of opposite valves, which are aligned and enter into joint communication, through joint central channels (45), with two adjustable lower hubs (22), whose center distance substantially corresponds to that of the two small valves (23) present on the head (24) of each drum (25).

[0019] The block (20) comprises a lower drain valve (26), an upper feed valve (27) of the product and a pressure switch (28).

[0020] The block (21) comprises a lower steam feed valve (29), an upper CO₂ feed valve and an overflow valve (31).

[0021] The structural concept, the composition of the valves, their preferably mushroom type, with drive by pneumatic pi­ston, their orientation and position, although preferred as described and illustrated, must not be considered bin­ding of the patent, but only given as example.

[0022] Various modifications to their structure, to their combi­nation and to their position may be made without depart­ing from the sphere and object of the invention.

[0023] During operation, the drums (25) are conveyed towards the machine by a conveyor belt with rollers (32), motorized.

[0024] On reaching the loading station (33), each drum (25) is loaded on a rotating plate (34) and held in position by pressing rollers (35), controlled by a piston (36). In alignment to said plate (34) is arranged an upper fixed structure (37) on which are applied two sensors (38), pre­ ferably composed of photo-electric cells. They are posi­tioned with a distance between them equal to that corre­sponding to the center distance between the two small valves (23) present on the heads (24) of the drums (25) and are positioned in such a way as to detect their pre­sence.

[0025] During its movement, the plate (34) makes the drum (25) rotate round its axis of vertical symmetry, so that the photo-electric cells (38), suitably orientated and posi­tioned, can detect the exact position and orientation of said small valves. The moment both photo-electric cells simultaneously detect the presence of the two small valves, the plate (34) stops. The drum (25) is thus perfectly and automatically aligned in the desired position.

[0026] A device with suckers (39), driven by a piston (40), fixes in position the drum (25); the pressing rollers (35) move away and the drum is pushed on the supporting deck (6). which in that moment is aligned to the loading station (33). Subsequently, the corresponding vertical piston (7) lifts the drum (25) until the small valves (23) are engaged with the lower hubs (22) of the distributor (9) present in that work head.

[0027] The hubs (22) are equipped with elastic seal gasket (41), pressure spring (42) and conic mouth (43), so that they are capable of containing and engaging perfectly with the small valves (23), even if there are any small errors of orientation.

[0028] In the continuation of the slow, continuous rotation of the rotating turntable (2), the drum (25), as soon as loa­ded, starts its treatment cycle, while another drum presents itself on the loading station (33) for orientation opera­tions.

[0029] Each drum (25) positioned on the supporting deck (6) drives the limit switch of drum presence; a second limit switch positioned on the central upper plate (17), with the con­sent of the presence of the drum, starts the various work cycles.

[0030] The treatment cycle starts with a first seal test to check the integrity of the structure of the drums, which consists in injecting inside them, through the opening of the valve (30), some CO₂ at the pressure of some bars and checking with a pressure switch that this pressure remains constant for a certain time.

[0031] If this takes place, it means that the drum in question is integral and the cycle may continue; if it does not take place, the station occupied by the faulty drum is excluded and, during rotation of the turntable (2), no operation is carried out, until discharge.

[0032] The same pressure test can be advantageously carried out with steam instead of CO₂; in this case the opening of the valve (29) instead of (30) is programmed and some dry sa­tuated steam is injected inside the drums (25) at the pres­sure of some bars and at the temperature of 100°C and over.

[0033] If the seal test is positive, the drain valve (26) is opened, with consequent decompression, which starts at any rate with the natural condensation of the steam in contact with the cold surface of the drums, and the sterilization phase is carried out; this consists in continuing the in­jection of dry saturated steam inside the drums (25) and allowing it to drain through the valve (26).

[0034] Sterilization is carried out for a determinate time, while the turntable (2) continues its slow rotation.

[0035] Following the preestablished programming, the steam valve (29) is closed and the CO₂ valve (30) opened; the drain valve (26) remains open.

[0036] The flow of CO₂ causes the drainage of all residual conden­sation and the perfect internal drying of the drums; fi­nally, the drain valve (26) closes and the drums are laoded with CO₂ at a slightly higher pressure than that to which the product to be transferred is submitted, then the CO₂ filling valve (30) also closes.

[0037] The filling phase then starts, with the opening of the pro­duct feed valve (27) and the start of opening of the overflow valve of the CO₂ (31), which is self-calibrated according to the pressure reached by the injected product.

[0038] In this way, a counterpressure is maintained inside the drums which makes it possible to carry out a regular, pro­gressive filling, without the formation of foam, bubbles and the like.

[0039] It should be noted that the insertion of the product in the drums is carried out through the traditional small filling valve (23), which, as known, presents a long internal chan­nel, with mouth facing the bottom, while the small drain valve (23) presents a shorter channel, facing the maximum filling level.

[0040] The control at end of filling may be carried out by means of a sensor (44) which detects the maximum level of liquid, or by means of a load cell (51), positioned above the support­ing deck (6), which detects the effective weight of the full drum. In this second hypothesis, illustrated in figs. 6, 7 and 8, the shank of the cylinder and the guiding shank, in­dicated respectively with (52) and (53), are extended in up­ward direction and carry the balance (54) with upper contain­ing plate (55); the prisms (56) are engaged in said shanks and obtain the "balanced" oscillation of the unit.

[0041] Below is parallelly provided the balance (57), with contain­ing plate (58) and prism (60) inserted with the same system in the shanks. The electric and/or electronic connections of the device are of known type and are therefore not de­scribed.

[0042] In each case, after filling, the feed valve (27) is closed, after which, as a part of product remains in the feed chan­nel of the heads, it is recovered by injecting it in the drum just loaded, by means of a momentary injection of CO₂ at higher pressure, with closure of the bleed valve (31) and temporary opening of the small valves (23) of the drum. This last phase, besides permitting the recovery of that part of product that would normally be lost at the start of the following cycle, makes it possible to carry out a per­fect cleaning and drying of all the valves with CO₂.

[0043] The sequence of phases shown above is carried out in totally automatic manner, under the control of the photo-electric cells (38), of the means of contact (18), of the push rods (31 ), of the load cells or of the sensors (44), substantially regulated and programmed by means of a computer, external or on board machine, like a PLC.

[0044] The drain valves (26), the product feed valves (27), the steam feed valves (29) and the CO₂ feed valves (30) are pre­ferably of type with pneumatic operation, as illustrated in figure (5), with the air inlets (11) derived and regulated by the inlet (50) present on the central distributor (14). Their operation, of known type, is not described in detail in the present report.

[0045] It is evident, however, that their mechanical structure is not binding but only relative to a preferred illustrative construction.

[0046] Said valves, or distributors, may therefore also be of other type, in the sphere of the innovative functional con­cept of the present invention.

[0047] At the end of the complete cycle, which substantially de­velops along the entire rotating route of the turntable (2), the vertical pistons (7) descend, freeing the small valves (23) of the drums from the corresponding distributors (9) and align the supporting decks (6) with a conveyor belt with motorized rollers (46). A second piston (47) with grip means with sucker (48), withdraws the filled drums from the decks (6) and deposits them on said conveyor belt. The arrangement on a rotating round turntable (2) and the number of work heads are unbinding, the same automatic functional concept may, in fact, also be applied on different construc­tions, for example with on-line arrangement or with any number of sequential heads. The round arrangement is, how­ever, preferred for questions of easier, cheaper distribu­tion, of general control of the machine, of maintenance and of bulk.

Claims

1) Machine with continuous cycle for the sterilization and filling of drums (25), and the like, characterized by the fact of comprising a sequential series of work heads equipped with groups of distributors (9), each formed by at least one product feed valve (27), a drain valve (26), a CO₂ feed valve (30), a steam feed valve (29) and an overflow valve (31), which are directly connected either to a cen­tral rotating distributor (14) or to a steam manifold (16), said distributors (9) being aligned and interconnected with adjustable hubs (22) which are engaged and coupled with the small valves (25) present on the heads (24) of the drums (25), which are engaged in the work loads through a loading and alignment station (33); said position being mairtainec up to the end of the work cycles.

2) Machine with continuous cycle according to claim 1, cha­racterized by the fact that the loading station (33) is con­nected to a conveyor belt (32) and comprises a rotating plate (34), which carries drums (25), connected to: pressing rollers (35), a pushing device with suckers (39) and an up­per fixed structure (37) on which are applied two sensors, e.g. photo-electric cells, which are positioned and orienta­ted according to the center distance and to the pre-­established orientation of the two small valves (23), present on the heads (24) of the drums (25); said sensors or photo­electric dells (38) being connected to the stopping system of the rotating plate (34), and being with intervention syn­chronized with the position of the small valves (23) in alignment to the detecting beam of said sensors.

3) Machine with continuous cycle according to claims 1 to 4, characterized by the fact that each supporting deck (6), on which the drums (25) are engaged under the action of the pusher with suckers (39), is equipped with a lifting piston (7) with rear guide (8), and is aligned to an upper distri­butor group (9).

4) Machine with continuous cycle according to claims 1 , 2 and 3 characterized by the fact that the sequential series of work heads is arranged in line, or is arranged on a ro­tating turntable (2), driven by a speed reducer (3) whose pinion (4) is engaged on a toothed crown (5), on which is fixed said turntable (2) complete with central rotating distributor (14).

5) machine with continuous cycle according to claims 1 to 7, characterized by the fact that the rotating distributor (14) is connected to an upper plate (17) on which are applied adjustable means of contact (18), alignable or not align­able to adjustable fixed push rods (19), and that said dis­tributor (14) is engaged in rotation on a central, coaxial fixed structure (15) in which are obtained the feed channels corresponding to the air inlets (11 ), the CO₂ inlets (12), the product inlets (13), and the discharge inlets corre­ sponding to the aperture (50).

6) Machine with continuous cycle according to claims 1 to 9, characterized by the fact of having the filling control of the drums composed of weight-detecting load cells (51), the shanks (52) and (53) of the cylinder and of guide ex­tended in upward direction, presenting at the top and bot­tom seats for the engagement of prisms (56) and (60) which produce the oscillation of the unit.

7) Machine with continuous cycle according to claims 1 to 6, characterized by the fact of having the filling control of the drums composed of level-detecting sensors (44).

8) Machine with continuous cycle according to claim 1, cha­racterized by the fact that the drain valves (26), of the product (27), of the CO₂ (30), of the steam (29) and of over­flow (31 ) are aligned according to common channels (45) and are preferably of pneumatic type.

9) Machine with continuous cycle according to claims 1 to 12, characterized by the fact that the continuous movement of the work heads, the valves, the control devices, the means of regulation, of intervention in closing and opening are directly connected to a programmable electronic elevator, like a PLC.

10) Machine with continuous cycle according to claims 1 to 13, characterized by the fact that, in the electronic pro­gramming of the control computer are provided, in sequence, a seal test phase with insertion of steam or CO₂ under pres­sure with possibility of suspension in case of presence of leaks, a sterilization phase with dry saturated steam in pressure with temperature over 100°C, a discharge phase of sthe residual condensations and of internal drying of the drums with CO₂, a pressurization phase of CO₂, a product filling phase in conditions of counterpressure of CO₂ over­flowing, a recovery phase of the product remaining in the heads with momentary pressurization of CO₂ and a washing phase in CO₂ of the channels of the valves of the distri­butors (9).

Drawing