THE CHALLENGE
Cosmosol, established in 1987 near Milan, Italy, is a company specializing in the production of various types of aerosol products. They deal with both the cosmetic and pharmaceutical sectors, including the manufacturing of medical devices, using traditional aerosol technology and the emerging bag-on-valve technology.
Cosmosol approached Nemesis with a request for a checkweigher capable of handling and weighing body spray bottles . The system needed to operate at a throughput of 100 pieces per minute, accommodating variable weights ranging from 150 to 300 grams.
THE SOLUTION
The application presented a significant challenge: the shape and lightweight of the spray bottles to be weighed.
The production line had to ensure the correct and secure handling of the bottles, as well as their passage on the sensitive weighing conveyor, without vibrations.
For Cosmosol, Nemesis customized a S Series Checkweigher from the S Series, certified under the MID (Measuring Instruments Directive) to weigh spray bottles and other cylindrical products with weights up to 600 g. The system operates at a throughput of 100 pieces per minute with a scale interval "e" of 0.5 grams.
The conveyor belts have a width of 90 mm and rest on rollers with a diameter of 20 mm.
EasySet servo-assisted feeding belts
Feeding belts have been installed on the conveyor of the checkweigher, whose function is to pick up the product from the packaging line, divert it towards the weighing conveyor, weigh it, and potentially reject it if it doesn't meet the criteria, all with no need to interrupt or modify the existing line.
Thanks to the EasySet system, the guides can be adjusted in width based on the exact diameter of the product, ensuring a perfect fit and allowing smooth movement on the conveyor with minimal friction.
This guarantees high operating speed and a high degree of accuracy.
Pneumatic ejector
To reject spray bottles detected as non-compliant in weight, a pneumatic ejector has been implemented, expelling them rapidly and directing them into a designated collection basket.
To ensure the maximum continuity of the pusher's operation, a safety pressure switch has been installed, detecting any drops in pressure in the compressed air supply.
The collection basket is also equipped with another safety feature: a photocell for full reject bins, indicating when the basket needs to be emptied.
THE BENEFITS
The high degree of accuracy of the system allows for gram-level weight control of extremely lightweight products.
The introduction of the feeding belts enables the precise and secure handling of spray bottles with no need to interrupt the existing packaging line.
Furthermore, by supporting the cylindrical-shaped bottles during their transition from the feeding conveyor to the weighing conveyor, the feeding belts prevent friction or contact with the edge of the weighing conveyor. This prevents disturbances in the weighing process and potential interference with the level of accuracy.
Thanks to this system, the pitch between the bottles can be very close.