Field of application
[0001] The present invention relates to the field of machines for cartoning of products
with multirow feeding.
Prior art
[0002] Machines with multirow feeding are a known type of cartoning machines. This term
of "multirow" feeding refers to the fact that the cartoning machine receives in input
the products (placed on a conveyor, belt or other system of translation) arranged
side by side in several substantially parallel rows. The number of rows can be any,
for example 6 or 12 rows. Due to this arrangement in rows the products are actually
fed by groups (batches) having a number of products corresponding to the number of
the rows.
[0003] The machines with multirow feeding are used typically for products having an elongated
shape and a small unitary size, which are well suited to this transport configuration.
A typical example is represented by stick packs.
[0004] The stick pack, as is well known, is a package having an elongated shape, made of
paper or plastic, formed by a substantially tubular body closed at the two ends, for
example by sealing or gluing. The stick pack experienced a rapid diffusion especially
in the field of individually packed products. By way of an example, it is widely used
for soluble products, including coffee, powdered drinks, etc., sugar or sweeteners,
dressings such as oil, vinegar, sauces, etc., in single-portion packs, which are popular
in the field of fast food restaurants for reasons of hygiene and practicality; pharmaceutical
products in small or medium dosage, especially in soluble powder, and others. The
stick pack is appreciated by manufacturers, in that it allows a certain saving in
material, and by customers.
[0005] There is therefore a growing interest in this type of package and, consequently,
in the related secondary cartoning machines, for example intended to carton a certain
number of finished stick packs, i.e. filled with product and closed, inside cardboard
boxes or packets. And, due to their narrow elongated shape, the stick packs are generally
transported in a multirow formation.
[0006] To summarise, the growing market interest in the stick pack forces the demand for
increasingly high flexibility and performances also of the related secondary cartoning
machines. In the following, reference will be made to the processing of products in
stick packs, by way of a preferred embodiment, the invention being however of general
application to both primary and secondary cartoning machines with multirow feeding.
[0007] In general terms a technical problem tackled by cartoning machines with multirow
feeding consists in managing the product grouping, i.e. the number of products that
the machine has to load in each of the cartons.
[0008] In the prior art the arrival of the products is managed with drop hoppers which collect
the batch of products and load it in a transport system forming one or more groups.
This solution however is not fully satisfactory: it imposes a considerable limitation,
i.e. it allows only multiple or submultiple groupings of the number of rows of feeding.
A batch of products arriving at the machine which, as mentioned above, is formed by
the same number of product units as the number of rows, can be:
- managed as unique group, intended for a single cartoning possibly with successive
groups, obtaining cartons which contain a number of products which is equal to or
a multiple of the number of rows,
- or divided into subgroups, obtaining cartons which contain a number of product units
corresponding to an exact submultiple of the number of rows.
[0009] The number of rows is normally set by the lines upstream of the cartoning machine
(for example the machines which fill and seal respective stick packs and/or the transport
system); consequently the cartoning machine is somewhat "rigid" in respect of the
format change, being forced to manage multiples or submultiples of the aforesaid number
of rows.
[0010] In other words, the basic operations of the cartoning machine can be identified as
receiving the products, their grouping and the so-called loading, referring with this
term to the arrangement of the products inside the cartoning, and in the prior art
of multirow machines the grouping performed by the loading is substantially constrained
to the entrance of the machine itself.
[0011] This limitation is particularly felt for mass consumption products, such as the already
mentioned freeze-dried coffee or powder preparations for soluble drinks, and so on.
In this field, both format changes and promotional offers a involving some free product
are fairly common. It is assumed, for example, a machine with 10-rows feeding and
configured to output packs of 20 products. A request from the client to produce batches
of packs with a 10% extra product (i.e. 22 products), for example for promotional
purposes, would be difficult and expensive (if not impossible) to fulfil, the number
of products (22) not being an exact multiple of the number of rows.
[0012] Another disadvantage of the prior art is that it does not allow a reliable check
as to whether the number of products loaded in a carton corresponds effectively to
what is required. The product units transported in multirow formation - for example
the aforementioned stick pack - are normally lightweight and small in size, and the
probability of an error (product shortage, product fall) is relatively high. The known
hopper-based machines therefore suffer a relatively high risk of forming a package
out of specification.
Summary of the invention
[0013] The object of the invention is to overcome the abovementioned disadvantages. The
invention sets out to provide a machine for cartoning of products with multirow arrival
capable of managing any grouping, not necessarily multiple or submultiple of the number
of rows in input, as well as capable of reliably providing that the grouping corresponds
to the specifications.
[0014] These objects are achieved with a machine for cartoning of products with multirow
feeding, comprising: an input section of said products; a first conveyor with single
grouping and operating with continuous motion, positioned to receive the products
from said input section; a products transfer section from said first conveyor to a
second conveyor; said second conveyor having an advance motion which is intermittent
and coordinated with the motion of the first conveyor, obtaining a predefined grouping
of the products on said second conveyor.
[0015] The first conveyor and the second conveyor each comprise a plurality of product-carrying
pockets or cells or equivalent means. Herein below the term of cell will be used generically.
The first conveyor with single grouping comprises cells configured to receive each
a single product unit. The cells of the second conveyor can contain any number of
products. Preferably said first and said second conveyor are linear, i.e. they impose
to the products a translation movement along a predefined path.
[0016] According to one of the aspects of the invention, the input section comprises a drop
hopper, said first conveyor with single grouping being positioned to receive the products
directly from said hopper and convey them towards said transfer section to the second
conveyor.
[0017] In a preferred embodiment the first conveyor is made with a conveyor belt which operates
according to a closed circuit; in the transfer section the first conveyor is located
above the second conveyor, the advancing directions of the first and second conveyor
being on parallel planes. More preferably, in the transfer zone the two conveyors
have opposite advancing sense, so obtaining a counter-flow transfer of the products.
[0018] The second conveyor can serve directly a carton loading section, equipped for example
with a top loading robot or with product insertion members, such as for example linear
pushers. In a preferred embodiment the second conveyor is represented by a servo train
conveyor. Said conveyor, which is known in the art, comprises essentially a plurality
of servo trains with independent control and motor drive, so that a train can be synchronised
with the motion of the first conveyor, while another train can be synchronised at
the same time with the loading system (for example robot or other insertion member).
[0019] The intermittent advance motion of the second conveyor is coordinated with the speed
of the first conveyor, in continuous motion, to determine the number of products that
are loaded in each of the cells or of the servo trains of the second conveyor.
[0020] An aspect of the invention provides that the machine is equipped with at least one
counting device associated with the product transfer section, and disposed for the
single count of the product units which are released from the first to the second
conveyor. Said counting device can be used to make available a signal enabling the
intermittent advance movement of said second conveyor. In other words the invention
allows the control system of the machine to advance the second conveyor only upon
a check that the number of product units in a cell (or train) corresponds to the specification.
It should be noted that said count is made possible by the single grouping of the
first conveyor.
[0021] The invention allows substantially to remove the link between the multirow input
and the load grouping. The grouping imposed by the multirow input is split by loading
the products one by one on the first conveyor; at the passage from the first to the
second conveyor the groups of products are newly formed, yet without any constraint
of compatibility (multiple or submultiple) with the input, the grouping being determined
solely by the coordination between the first and the second conveyor.
[0022] In short, the first conveyor operates as an element of interface between the input
section of the machine, forced to the multirow feeding, and the loading section. In
observance of the general continuity, a machine according to the invention is virtually
capable of obtaining any grouping in the cartons and is capable of easily modifying
the grouping without affecting the input. The single count also allows the machine
to automatically correct a product shortage. The control can maintain a cell or train
of the second conveyor in a loading position until the consent of the counting system,
so that possible "gaps" on the first conveyor do not generate an error in the loading,
for example a missing product in a package.
[0023] A preferred application of the invention consists of a machine for secondary cartoning
of products in stick packs.
[0024] Another aspect of the invention consists of a method for loading products fed with
a multirow formation into cartons, comprising at least the following steps: loading
of the products on a first conveyor, with single grouping; transfer of the products
from said first conveyor to a second conveyor; said first conveyor having a continuous
advance motion and said second conveyor having advance motion which is intermittent
and coordinated with the motion of the first conveyor, obtaining a defined grouping
of the products on said second conveyor.
[0025] The advantages of the invention, which have been mentioned above, will be more apparent
with the aid of the following description, referred to a nonlimiting example.
Description of the drawings
[0026]
Fig. 1 represents schematically some elements of a machine according to an embodiment
of the invention.
Fig. 2 is a detail of Fig. 1.
Fig. 3 is a detail of a possible embodiment of the invention, with reference to the
zone of transfer of the products from the first to the second conveyor.
Fig. 4 is a block diagram of a method of loading of products into cartons, the products
being fed in a multirow formation, according to a mode of implementation of the invention.
Detailed description of the invention
[0027] Referring to the drawings, a cartoning machine receives products in stick packs arranged
in multirow configuration. The products arrive via a multitrack chute 1 in a hopper
2 and are loaded one by one in product-carrying cells of a first conveyor 3 with continuous
motion.
[0028] Said conveyor 3 operates in a closed circuit between a product receiving zone 3a
and a product delivery zone 3b, and is constituted substantially by a conveyor belt
actuated by a motor 4. The conveyor 3 preferably has a path as illustrated, with a
rising tilted section passing from the loading zone 3a to the delivery zone 3b. In
the zone 3a the products are released directly by the drop hopper 2 into cells of
the conveyor 3.
[0029] The loading into the conveyor 3 is exemplified in Fig. 2. The stick packs are fed
to tracks defined between walls 5 of the loading chute 1, arriving at the hopper 2
in a multirow formation, contained in compartments 6. The example refers to an input
of twelve products at a time, i.e. twelve rows. The opening of said hopper 2 causes
the products to drop from the compartments 6 into a corresponding number of cells
7 of the conveyor 3 below, at the zone 3a. Each cell 7 carries a single product P.
In the example the cells 7 are defined by metal or plastic pockets 8 attached to a
conveyor belt.
[0030] The interface between the first conveyor 3 and the second conveyor, denoted generally
by 9, is shown in Fig. 3.
[0031] The second conveyor 9 in the example is a servo train conveyor with intermittent
movement. It comprises a plurality of servo trains, each being formed by a plurality
of pockets 10 which define product receiving cells 13. Each of said cells 13 can contain
a product P or possibly a plurality of products P adjacent or stacked one above the
other.
[0032] A set of pockets 10, connected to a respective conveyor belt 12, forms a servo train.
The conveyor 9 comprises at least two conveyor belts with independent control and
motor drive and, consequently, at least two servo trains which are driven in an independent
manner. In the example the pockets 10 are attached to the respective conveyor belt
with blocks 11 which allow quick fitting and change.
[0033] The second conveyor 9 feeds a loading section of the products inside the cartons,
which can be for example cardboard packets. This section can be made with a known
technique and according to the relevant needs and therefore is not described in detail.
For example the second conveyor 9 can feed a loading system comprising a top loading
robot or a series of inserting members which transfer the products directly into the
cartons, More specifically, the second conveyor 9, realized with the abovementioned
servo-trains technique, can be driven in such a way that at least one servo train
is charged to receive products from the continuous conveyor 3, while another servo
train feeds said loading system. The content of one or more of said cells 13, according
to the configuration of the machine, corresponds to the carton grouping, i.e. to the
number of products per each carton.
[0034] A closing assembly can be provided downstream the loading section, still according
to a per se known technique.
[0035] Fig. 3 shows an embodiment wherein a return portion of the first conveyor 3 is positioned
directly above a portion of the second conveyor 9, so that the products P pass from
the cells 7 of the first conveyor to the cells 13 of the second conveyor below by
a free falling. Guides 14 are provided around the pulley 15 of the conveyor 3 which
extend to an end 14A, beyond which the product P falls into a cell 13A below. In the
figure, the cell 13A is then located in the actual zone of transfer of the products
from one conveyor to the other.
[0036] The sense of the advance of the conveyors 3 and 9 is denoted by A and B, respectively.
It can be noted in the figure that the sense A of advance of the first conveyor 3
is opposite to sense B of advance of the conveyor 9, in the transfer section 3b.
[0037] The described arrangement with a section of the first conveyor above the second conveyor,
and counter-flow movement on parallel planes, is advantageous in terms of the compact
size, in particular reducing the overall length dimension, and of the constructional
simplicity.
[0038] The machine comprises an optical sensor (not shown) which allows the single count
(one by one) of the products passing from the continuous conveyor 3 to the cell 13A
of the conveyor 9. In the example the sensor can be positioned at the end 14A of the
guide 14 to detect the products which one after the other fall into the cell 13A.
When the loading of products is completed, the conveyor 9 moves one step forward,
bringing the next cell into the loading position. It is clear that the control system,
thanks to the counting sensor, can receive the information of the number of products
which have actually passed into the cell 13A and, therefore, can enable the forward
movement of the conveyor 9 only when said number corresponds to the functioning specification
of the machine. The machine can thus manage any "gaps" (product shortage) on the conveyor
3. If for example one of the cells 7 is empty, the system can delay the forward movement
of the second conveyor 9 until the correct number of products is present in the cell
13A.
[0039] It is also clear that the machine is capable of generating any grouping on the successive
conveyor 9 and then in the cartons, due to the products being loaded singularly one
by one on the conveyor 3.
[0040] When a train on the conveyor 9 is full, it moves forward quickly to the loading section
while a next train is positioned with the first cell in the position 13A of Fig. 3.
[0041] The method according to the invention is exemplified in the diagram of Fig. 4. It
comprises substantially a step 100 of products arrival in a multirow formation; a
step 101 of single transport of the products; a step 102 of grouping; a step 103 of
loading in cartons. The operation of single count of the product units, indicated
by the block 104, is carried out between the steps 101 of transport and 102 of grouping.
[0042] In the example of Figs. 1-3, the step 100 of arrival takes place at the hopper 1;
the step 101 of single transport is operated by the first conveyor 3; the grouping
step 102 takes place during the passage of the products into the second conveyor 9,
thanks to the coordination between the latter and the first conveyor 3.
1. Machine for cartoning of products (P) with multirow feeding, comprising:
- an input section (1) of said products (P);
- a first conveyor (3) with single grouping and operating with continuous motion,
disposed to receive the products from said input section;
- a products transfer section (3b) from said first conveyor (3) to a second conveyor
(9);
- said second conveyor (9) having an advance motion which is intermittent and suitably
coordinated with the motion of the first conveyor, obtaining a predefined grouping
of the products on said second conveyor.
2. Machine according to claim 1, comprising a loading section for loading the products
into cartons, said loading section being fed by said second conveyor (9).
3. Machine according to claim 1 or 2, said input section comprising a drop hopper (2)
and said first conveyor (3) with single grouping being disposed to receive the products
directly from said hopper and to convey them towards said transfer section (3b) to
the second conveyor (9).
4. Machine according to any one of the previous claims, said first conveyor comprising
cells (7) configured to contain each a single unit of said products (P); said second
conveyor comprising cells (13) configured to contain one of said products or a plurality
of said products.
5. Machine according to any one of the previous claims, said second conveyor (9) being
made with a conveyor comprising a plurality of servo trains, each servo train being
formed by a plurality of pockets (10) which define product receiving cells (13), the
pockets of each servo train being connected to a respective conveyor belt (12); the
conveyor comprising at least two conveyor belts and respective servo trains with independent
control and motor drive.
6. Machine according to any one of the previous claims, comprising at least one counting
device associated with said products transfer section (3b) and disposed for the single
count of the product units (P) transferred by the first conveyor (3) to the second
conveyor (9).
7. Machine according to claim 6, wherein said counting device supplies an enabling signal
for the step by step advancement of said second conveyor(9).
8. Machine according to any one of the previous claims, wherein said first conveyor (3)
is formed with a closed circuit conveyor belt and a section of path of the first conveyor,
at said transfer section, is located above the second conveyor (9), allowing the passage
of the products from the first to the second conveyor by free falling.
9. Machine according to claim 8, the directions of advance of the first (3) and second
(9) conveyor being situated on parallel planes in the products transfer section (3b).
10. Machine according to claim 9, the sense of the advance movement (A, B) of said first
conveyor and second conveyor being opposite in the products transfer section.
11. Machine according to any one of the previous claims, the machine being a machine for
secondary packaging of products in stick packs.
12. A method for the loading in cartons of products fed with a multirow formation, comprising
at least the following steps:
- loading of the products on a first conveyor (3), with single grouping;
- transfer of the products from said first conveyor (3) to a second conveyor (9);
- said first conveyor (3) having a continuous forward motion and said second conveyor
(9) having forward motion which is intermittent and coordinated with the motion of
the first conveyor, with obtaining of a defined grouping of the products on said second
conveyor.
13. Method according to claim 12, wherein a single count of the products is carried out
during the step of transfer of the products from said first conveyor to said second
conveyor.
14. Method according to claim 12 or 13, wherein the products are loaded directly from
said second conveyor inside said cartons.
15. Method according to one of claims 12 to 14, said products being represented by stick
packs of elongated shape, formed by a substantially tubular body closed at the two
ends.