Those whose business involves chocolate (in all its many forms) know all too well the importance of the stage in which the “moulded” products are transferred to the primary packaging machine.
This is the moment in which a series of variables enter the picture, tied to the form of the product and the feeding system of the packaging machine. Added to this is a problem of available space: production facilities are not always overly generous with space to dedicate to packaging.
Bearing this in mind, it is not hard to see how important it is to have an ad hoc conveyor system that takes into account:
- the type of product to be transported;
- the feeding system of the primary packaging machine;
- available space;
- any devices that may be able to increase the efficiency of the line.
That is why, in this blog post I would like to provide an overview of the main feeding systems for primary packaging of chocolate.
All products, from the classic chocolate bars, through “hollow” forms (such as Easter eggs and bunnies, for example), all the way to the most carefully crafted pralines share a fundamentally similar production process, known as moulding. This is the most fascinating moment in the process, the one in which the chocolate takes shape.
Moulding generally involves the products travelling through special moulds and trays, so there are no particular differences between one product and the next in terms of the conveyor technology required.
When the chocolate is removed from the moulds (known in jargon as “demoulding”) the differences begin to be felt between the different types of products and packaging.
There are essentially three types of feeding system.
Hollow eggs and delicate/intricate pralines
In these cases, the product remains in trays known as counterplates until the moment they are loaded into the packaging machine, usually using a so-called “pick and place” system.
This process generally involves the following equipment:
- Conveyor belts
These can be of different types and they carry the plates either along the short or long sides, facing forwards.
- Expulsion system
Placed after the metal detector and activated by pneumatic cylinders or brushless motors, this is responsible for ejecting plates with contaminated products. The plates must then be cleaned and reinserted manually (in the majority of cases).
Only lines that handle products with high margins can justify a fully automated recovery system.
Bucket or ledge elevators are the ideal solutions for lines with relatively long work cycles. The ideal solution incorporates a motorised brushless axis to control the positioning and acceleration, offering a solution that ensures fluid and risk-free motion even when the plates are full.
- Plate rotator
This device is usually the last one in the return line. The plate is presumed empty, but the packaging loader may have missed a few pieces that are still in the mould; therefore, before returning it to the demoulding position, it must be turned upside down and shaken to ensure any residual pieces fall out.
Once the plate has been definitively emptied, it can return to the start of the line and restart the cycle.
Small flat-bottomed chocolates
These usually use chicane conveyor belts that align the product and divert it towards the different wrappers.
This uses the classic rank feeding system that can load both wrapping paper and flowpack. In these cases, the products must be arranged in single file at one or more exits before they enter the machine.
To meet this need, merge and align groups for unpackaged products are used.
The standard merge group consists of three belt or modular chain conveyors that operate at different speeds, to separate the arriving products. Above the belts there are a few pairs of fixed guides or motorised belt diverters with adjustable inclines, that slow some products down and allow those they do not touch to pass, thereby breaking up the threading process.
To buffer large volumes of the unpackaged product by rank, we need a multiple cleave belt that follows the FIFO principle (First In — First Out); the cleaves can either be fixed, fed by a tilting conveyor or organised in a single rack that can be raised and lowered. This second solution is critical in production facilities where available space is at a premium.
The packaging machines are fed by exit lines that are perpendicular to the primary transportation line. The exit lanes receive the product from the primary transportation line through oscillating devices.
Before they can reach the primary packaging, the products must often be rotated and separated to ensure the efficiency of the line. The task is carried out using a series of conveyor belts that carry out successive jumps in speed, to ensure adequate spacing between the products.
M.H. produces all of the solutions described above, focusing first and foremost on the specific needs of each client, to tailor and optimise the entire packaging process for them.
M.H. is an Italian brand with thirty years of experience with handling movement and logistics within production facilities in every sector of industry, providing conveyor belts, merge and sort accumulation systems, item rotators and flippers, lifts, destackers and other accessories necessary in the packaging and product manufacturing process.
Thanks to their modular design, M.H.’s products are interchangeable and easy to integrate into existing lines.
To find out more about how to improve the efficiency of the entire packaging process of your products
Co-Owner M.H. Material Handling S.p.a.