When packing meat products, food manufacturers are increasingly opting for smaller self-service packaging, thus adapting to the rise in the number of single households. Due to demographic change, statistics show that around 60% of households in Germany alone are occupied by one person and the trend is on the increase.
However, smaller packaging units also mean a shift in a proportion of the production costs. The packaging is becoming more expensive than the product inside it.
For the packaging area this means that incorrect packaging – such as a wrong or faulty product, missing label or no best-before date on the label, underweight product, etc. – must be avoided at all costs. If many of these errors occur in one delivery, in certain circumstances the retailer may return the entire consignment.
Seen from this perspective and in view of the need for performance data, automated packing without quality control of the goods is no longer an option today. The ITEC • ATTEC Company Group has recognised this problem and has made it possible to check the goods with an optical control system before they are packed.
In the system being discussed, the same optical systems were used for a wide range of monitoring tasks relating to sausage products.
Before the sausage products are labelled, their dimensions are checked to separate out any that may be underweight. The same thing happens with soiled or damaged casing in the visible area of the camera. These products do not make it to the labelling machine. This already eliminates a proportion of faulty packaging.
Once the products have successfully passed through the first quality control test, they are conveyed to the labelling section. After this has been done, it is important to detect products with no label, or a label that is not attached correctly, or one which has no best-before date printed on it. It may also be possible to check that the product has been given the correct label. In this case, the correct product is determined via the colour of the aluminium clip and compared with an identification mark or with the text on the label.
If at least one of the faulty features has been detected, the product is removed from the process, thus avoiding the prospect of wrongly labelled products first being identified by the retailer, or, in the worst-case scenario, by the end customer.
The goods are then gathered together in four groups of five and placed in the waiting open packaging on a deep-drawing machine using a robot and a specially developed vacuum gripper.
At present, between 540 and 580 products per minute are automatically packed in a two-shift operation at the plant under consideration.
Thanks to the integration of these optical quality control tests, it has been possible to eliminate a number of faulty packs. Mechanical automation also increases hygienic protection of the product and ensures the continual flow of products whilst also raising capacity.
The following controls are possible with the help of an optical system:
Avoid delivering consignments containing products with wrongly labelled best-before dates
- Simple checking of the date for existence, accuracy and legibility
- Check the presence and position of the correct label
- Solid recognition despite varying surfaces and reflections
- Quick adjustment to the intended position by means of an external teach-in
- Check to ensure that transport containers have been completely emptied
- Detection of foreign bodies, irrespective of their shape or colour
- Additional verification of the container geometry
- Positional monitoring of the product track
- An average of 30 inspections per second
- No time-consuming training necessary to recognise font styles
- Integrated code reader for product identification reads all common 1D and 2D codes.