Device for synchronizing a series of packaging machines positioned along a chain conveyor, especially in the confections industry

The invention concerns a device for synchronizing a series of packaging machines positioned along a chain conveyor, expecially in the confections industry, that is intended for use when articles are to be packaged individually in one packaging machine and supplied to a downstream packaging machine for packaging as a set, characterized in that a chain-and-pusher buffer is interposed in the chain-conveyor section (C) connecting two (A & B) of the packaging machines and carrying the pushers (6) for the individually packaged articles (1) and in that each packaging machine (A & B) has its own chain-drive mechanism (8 and 9 respectively), both of which are connected to one set of electronic controls that carry out the synchronization.

The invention concerns a device for synchronizing a series of packaging 
machines positioned along a chain conveyor, especially in the confections 
industry, that is intended for use when articles are to be packaged 
individually in one packaging machine and supplied to a downstream 
packaging machine for packaging as a set. The articles packaged 
individually in the first machine have always been assembled together on a 
conveyor belt and a specific quantity at a time supplied therefrom to the 
set-packaging machine by means of an inserter, with the throughput of the 
set-packaging machine depending on the capacity of the belt between the 
two machines and necessitating careful monitoring. This has a very 
deleterious effect on the throughputs of each machine. Furthermore, this 
method of processing can only be used with articles that collide on the 
belt and can withstand the resulting impact. 
The object of the present invention is to eliminate this restriction and to 
provide a device for synchronizing a series of packaging machines 
positioned along a chain conveyor, especially in the confections industry, 
in which the synchronization of the series of machines is completely 
automatic and continuous, with the articles to be packaged subjected to no 
stress and without the operation of the packaging line being disrupted. 
This object is attained in accordance with the invention in that a 
chain-and-pusher buffer is interposed in the chain-conveyor section 
connecting two of the packaging machines and carrying the pushers for the 
individually packaged articles and in that each packaging machine has its 
own chain-drive mechanism, both of which are connected to one set of 
electronic controls that carry out the synchronization. 
The pushers for the articles to be packaged are positioned at intervals 
along the chain conveyor and are in accordance with the invention 
accommodated in a stationary channel that connects both packaging 
machines, the conveyor is allowed to form a sag between each pair of 
pushers in the vicinity of the channel, and there is a rotating mechanism, 
which drives the conveyor, at the outtake end of one packaging machine and 
at the intake end of the other packaging machine, both mechanisms being 
connected to the electronic controls that carry out the synchronization. 
The sags in the chain conveyor, which travels with its pushers along the 
stationary channel, are preferably supported on a channel that parallels 
the conveyor and can be shifted transversely with respect to the 
stationary channel. The degree of sag in the conveyor and its arrival in 
the set-packaging machine can be varied in relation to operating 
conditions by raising or lowering the adjustable channel. 
The rotating mechanism associated with the first packaging machine is 
controlled by a device that monitors the loading of the chain conveyor and 
synchronized with the rotating mechanism associated with the second 
packaging machine in such a way that both mechanisms contribute to 
advancing the conveyor, and the synchronization system regulates the 
throughput of the second machine appropriately when the speed of the first 
rotating mechanism changes.

Two packaging machines are positioned in series along a worm conveyor 6 as 
illustrated in FIG. 1. Machine A, the master, produces individually 
packaged articles 1 for assembly into packaging sets 2, each consisting 
for example of three individually packaged articles 1, each set to be 
introduced into a separate wrapper. This is the function of Machine B, the 
slave, which is a tubular-sacking machine that places three individually 
packaged articles 1 at a time for instance in a tubular sack of plastic 
sheet. The plastic sheet travels in a web 3 that is sealed between each 
pair of packaging sets 2 and separated, with ready-to-ship packages 5 
leaving the machine. 
Section C of the line consists of a chain conveyor 7 with pushers 6 that 
travels over pulleys 8, 9, and 10. Conveyor 7 is longer than the actual 
conveyor line, in which it is supported on its pushers 6 on a stationary 
channel 11. It is long enough to allow sags 7', the significance of which 
will be described later herein, to occur between pushers 6 in the vicinity 
of channel 11. 
Chain conveyor 7 is driven by rotators 12 and 13 in the vicinity of 
packaging machines A and B respectively. 
Chain conveyor 7 is supplied with individually packaged articles 1 by a 
loading chain 14 that also has carriers and that transfers the articles 
individually to channel 11, where they are accepted and transported by the 
pushers 6 on chain conveyor 7. 
At the end of chain-conveyor section C is another chain or belt conveyor 15 
or similar mechanism that accepts packaging sets 2 and introduces them 
into tubular-sack packaging machine B. 
In the vicinity of the rotator 12 associated with packaging machine A is a 
one-stop clutch 16 that is driven by rotator 12 and activated by a magnet 
17. 
Below channel 11 is another channel 18 that supports and positions sags 7' 
and can be shifted transversely with respect to channel 11. When, for 
example, channel 18 is shifted into the position indicated by the broken 
lines in FIG. 2 the sag or sags 7' will become shorter, increasing the 
length of chain conveyor 7. 
The operation of the device will now be described. 
Individually packaged articles 1 arrive on channel 11 from packaging 
machine A. The throughputs of the individual components are matched in 
such a way that packaging sets 2, each consisting of three individual 
articles for instance, are assembled on this section of the conveyor line 
out of individually packaged articles 1, accepted by the pushers 6 on 
chain conveyor 7, and supplied to packaging machine B. The individually 
packaged articles can for example be squares or bars of chocolate, 
Neapolitans, pralines, cookies, or other types of confectioneries, which 
leave packaging machine B in packages of three. 
If an individually packaged article 1 is missing from chain conveyor 7 for 
any reason, the throughput of packaging machine B will be modified by 
electronic controls that are not illustrated in detail. The drive 
mechanism 12 of rotator 8 must precisely correspond quantitatively to one 
interval of chain conveyor 7. The conveyor must always continue moving in 
the vicinity of the chain-conveyor section. Since sags 7' provide it with 
longitudinal compensation, when there is a malfunction on the part of 
packaging machine A or in loading chain conveyor 7 with the requisite 
number of individually packaged articles 1 for a packaging set 2, chain 
conveyor 7 can continue into tubular-sack packaging machine B but will be 
extended due to the corresponding resolution of sags 7'. Rotator 8 will on 
the other hand shut down during such a malfunction due to activation of 
one-stop clutch 16 by magnet 17. Other electronic controls, not 
illustrated, will convert the brief shutdown of rotator 8 into a 
corresponding continuous deceleration of rotator 9 to equalize the 
different number pulses in rotators 8 and 9. 
If a series of too many articles for the length of the conveyor is missing, 
the mechanism that drives packaging machine A or rotator 8 will shut down, 
whereas chain conveyor 7 will continue to advance. Once articles begin to 
be supplied from packaging machine A again, one-stop clutch 16 and 17 will 
turn rotator 8 on again and the mechanism that drives rotator 9 will 
accelerated in accordance with the difference in pulses. When the speed of 
packaging machine A is regulated, the throughput of packaging machine B 
will be adjusted by the synchronization device.