Weight check with adjustment lane

A Verona-based company engaged in the processing and distribution of fruits and vegetables requested a checkweighing and rejection line for baskets of strawberries and mushrooms weighing from 300 to 500 g.

The system, after weighing, had to allow the recovery of trays that were out of weight, ensuring the maximum integrity of the product, so that they could then be reintroduced into the production cycle with the correct weight.

Nemesis designed and implemented a special weighing line with a checkweigher and recirculating conveyors for them, configured as follows:

1. A system of double conveyor belts, each 4.5 meters long, operating in the opposite direction, transporting the baskets on two automated roller islands positioned at opposite ends.
2. In the center, a checkweigher with a scale interval of 1 gram, capable of weighing up to 80 pieces per minute. From the entry conveyor, the baskets are directed towards the weighing conveyor: if the weight is compliant, the basket continues towards the end of the line to reach the next downstream packaging station. However, if the basket's weight is non-compliant, the roller island located before the end of the line intercepts the non-compliant basket, thanks to a system of photocells, and moves it with a pneumatic diverter to one row if it is underweight or to another row if it is overweight. Both rows of non-compliant baskets are transported in front of an operator who manually corrects their contents, adding or removing the product, depending on the row they are in.
3. Once the content is manually corrected, the baskets arrive on the other roller island, which directs them all into a single row and recirculates them on the weighing conveyor for further inspection.

• Thanks to the specific diverters on rollers, the out-of-weight bins are rejected without being touched or handled, ensuring that their delicate content is not damaged. 
• The recirculating lanes with islands allow for the retrieval of all bins, achieving a 100% production control. 
• The rejection system is simple and intuitive. The operator easily identifies the overweight or underweight basket and can immediately correct it. This allows for maintaining high production speed. 
• The certainty of packaging and introducing products to the market that exactly match the label and/or agreement with the customer helps avoid contractual penalties and strengthens the image as a quality producer.