Method and device for filling containers   

TECHNICAL FIELD

The present invention relates to a method and device for filling a container.

The present invention may be used to advantage in the packing of confectionery products, to which the following description refers purely by way of example.

More specifically, the present invention relates to a device for filling a container with single (i.e. separate) articles.

BACKGROUND ART

Known devices for filling a container normally comprise a conveyor for feeding the container through a filling station, where a feed assembly feeds a number of articles into the container. The articles are normally fed to the filling station by a so-called “slat” conveyor and drop freely down a funnel-shaped chute into the container.

One example of a known (device for filling containers is described in U.S. Pat. No. 2,920,743.

Known devices of the type described above have numerous drawbacks, including: frequent clogging of the chute; damage to the articles, especially as they drop down the chute into the container; inconsistency in the number of articles fed into the containers; low output rate; and cleaning difficulties—in particular, the slat conveyor must be dismantled completely to be cleaned.

It is an object of the present invention to provide a filling device and method designed to at least partly eliminate the drawbacks of the known art, and which at the same time are cheap and easy to implement.

According to the present invention, there are provided a device and method for filling containers, as claimed in the accompanying independent Claims and, preferably, in any one of the Claims depending directly or indirectly on the independent Claims.

BRIEF DESCRIPTION OF THE DRAWINGS

A non-limiting embodiment of the invention will be described by way of example with reference to the accompanying drawings, in which:

FIG. 1 shows a partial front view of a device in accordance with the present invention;

FIG. 2 shows a larger-scale detail of FIG. 1;

FIG. 3 shows a larger-scale, partial view in perspective of a further detail of the FIG. 1 device;

FIGS. 4 and 5 show partly sectioned side views of a detail of FIG. 1 in two successive operating positions;

FIG. 6 shows a section along line VI-VI of the FIG. 4 detail.

Number 1 in FIG. 1 indicates as a whole a device for filling a container 2, and which comprises a conveyor assembly 3 for feeding container 2 continuously along a substantially horizontal path P through a number of filling stations 4; and a number of feed assemblies 5, each located at a respective filling station 4 to feed a given number of single articles 6—in particular, tablets—into container 2 through an upward-facing opening 7 of container 2.

It should be pointed out that alternative embodiments may comprise other than the ten feed assemblies 5 shown in the FIG. 1 embodiment.

Conveyor assembly 3 (FIG. 3) comprises two substantially parallel chains 8 and 9 moving in time with each other along path P, and of which chain 8 is located above chain 9.

Conveyor assembly 3 also comprises a number of clamping members 10 projecting horizontally from chain 9 to accompany and push containers 2 along path P. In actual use, each container 2 is housed between two successive clamping members 10.

Conveyor assembly 3 also comprises a number of—in the example shown, three—rails 11, between which, in use, container 2 slides as it is fed along path P; and a top rail 12 for holding a panel T of container 2 in such a position as to permit free access to the inside of container 2 through opening 7.

With particular reference to FIGS. 3, 4 and 5, device 1 comprises a number of actuator assemblies 13, each for activating feed assemblies 5 as container 2, in use, is positioned at (i.e. travels past) respective filling stations 4.

Each actuator assembly 13 comprises a respective supporting-plate 14 fitted integrally to chain 8; and a respective arm 15 having one end 16 fitted to supporting plate 14 to oscillate about a respective substantially horizontal axis 17 parallel to path P.

Each actuator assembly 13 also comprises a respective elastic member 18 (in particular, a spring) having one end 19 connected to relative supporting plate 14, and one end 20 connected to relative arm 15. Each elastic member 18 holds relative arm 15 in a lowered position (shown in FIG. 4), while at the same time allowing arm 15 to swing upwards into a raised position (shown in FIG. 5).

Each actuator assembly 13 also comprises a respective bearing 21 fitted to relative arm 15 and rotating about a respective axis 22 substantially crosswise (in particular, perpendicular) to axis 17. When actuator assembly 13, in use, arrives at filling stations 4, bearing 21, as it travels parallel to path P, comes into contact with a profile B, and is raised to move arm 15 into the raised position (FIGS. 4 and 5).

Each feed assembly 5 (FIGS. 1 and 2) comprises a respective dispenser unit 23 for feeding a given number of articles 6 (in the example shown, one) into container 2; and a respective feed conduit 24 for feeding articles 6, stacked one on top of another, downwards from a hopper 25 (shown schematically in FIG. 1) to relative dispenser unit 23.

Each feed conduit 24 (as shown more clearly in FIGS. 4 and 5) is bounded externally by a respective coiled elastic sheath, and is deformable to adapt to the geometry of device 1, and to allow fast, easy intervention by the operator in the event feed conduit 24 becomes clogged. In this connection, it should be stressed that the coiled elastic sheath enables visual location of a jammed article 6, by stretching feed conduit 24, and release of the jammed article 6, by moving feed conduit 24, with no need to remove any other parts, or stop operation, of device 1.

Each dispenser unit 23 comprises a respective conduit 26, which extends substantially vertically, has a top end 27 connected to a bottom end 28 of relative feed conduit 24, and provides for feeding the stacked articles 6 downwards.

Each dispenser unit 23 also comprises a respective annular connecting member 29 (see in particular FIG. 6) mounted substantially coaxially with conduit 26 and oscillating about a substantially horizontal axis 30 crosswise to conduit 26. A respective control arm 31 is connected integrally to each connecting member 29, and is raised by arm 15 when arm 15 is in the raised position.

Each dispenser unit 23 also comprises two respective arms 32 and 33 extending downwards on opposite sides of axis 30 and, in particular, substantially vertically from connecting member 29. A respective supporting tab 34 is connected to a bottom end 35 of each arm 32, and extends substantially horizontally to support, in use, from underneath and in a relative position L over path P, a bottom article 6′ of a stack 36 of articles 6 formed inside conduit 26 and feed conduit 24 (FIG. 4). A respective supporting tab 37 is connected to a bottom end 38 of each arm 33, and extends substantially horizontally inside a hole H in conduit 26.

In actual use, when control arm 31 is raised (FIG. 5), the connecting member and arms 32 and 33 oscillate about axis 30, so that article 6′ drops down, and supporting tab 37 supports the bottom of stack 36 by moving into contact with the next article 6 up from article 6′. As can be seen, the number of articles 6 fed into container 2 at each filling station 4 can be changed easily by changing the length of arm 33 and the location of hole H along conduit 26.

Device 1 also comprises a number of known detectors 39 (shown schematically), each located at a bottom end of each conduit 26 to detect passage of articles 6 along conduit 26 and, therefore, insertion of articles 6 inside container 2; and a control unit 40 connected electrically to detectors 39, and for activating one or more feed assemblies 41 as a function of the findings of detectors 39. More specifically, upon detectors 39 finding a given number of articles 6 have not been fed into container 2, a number of feed assemblies 41, corresponding to said given number, are activated to make up for the detected shortage. Obviously, if each feed assembly 41 provides for feeding only one article 6 into container 2, the number of feed assemblies 41 activated equals the given number of articles 6 not fed into container 2.

It should be pointed out that, though the FIG. 1 embodiment comprises two feed assemblies 41, device 1 may comprise a different number of feed assemblies 41, e.g. one, three or four.

Feed assemblies 41 are located along path P, downstream from feed assemblies 5, and are substantially identical to feed assemblies 5, the only difference being that they are activated pneumatically, as opposed to mechanically by the passage of actuator assemblies 13.

Operation of one feed assembly 5 will now be described, as of the instant in which container 2 is fed to respective filling station 4.

As container 2 enters filling station 4, arm 15 is moved into the raised position (FIG. 5), by the interference of bearing 21 with profile B, and contacts an end 42 of control arm 31 opposite connecting member 29. End 42 is thus raised, so that connecting member 29 and arms 32 and 33 oscillate about axis 30, article 6′ drops down (FIG. 5), and stack 36 is supported from underneath by supporting tab 37. It should be pointed out that, at this stage, container 2 is positioned directly beneath conduit 26, and article 6′ is detached from the bottom end of stack 36.

Once container 2 leaves filling station 4, end 42 is lowered and, by virtue of a spring system (not shown), connecting member 29 and arms 32 and 33 oscillate about axis 30 in the opposite direction to before, so that stack 36 drops down and is supported from underneath by supporting tab 34, and the bottom end of stack 36 moves into the position L formerly occupied by article 6′.

It should be pointed out that, by articles 6 defining stack 36 at filling station 4, the number of articles 6 fed into container 2 can be controlled extremely accurately, and articles 6 can be transferred from the feed assembly into container 2 extremely quickly, with no risk of damaging articles 6. Feeding container 2 continuously along path P, combined with fast insertion of articles 6 inside container 2, provides for achieving extremely fast filling speeds.

The overall output rate of device 1 is further improved by the possibility of activating feed assemblies 41, and of clearing conduits 24 with no need to remove any other parts of device 1 and/or shut down device 1.