How contrast sensors keep production sweet

IN THE fast-paced world of confectionery production, efficiency and accuracy are paramount. Ensuring every product is correctly labelled isn't just about aesthetics; it's critical for traceability, quality control, and ultimately, customer satisfaction. This is where advanced factory automation, specifically smart sensing technology, plays a pivotal role.

Imagine a high-volume confectionery line: sealed cartons of delectable bagged candy whizzing along conveyors towards a labelling station. At this crucial point, precise label application and verification are essential. Any misalignment or missing print marks can lead to significant headaches down the line, from untraceable products to costly recalls.

The Challenge: Maintaining Label Integrity at Speed

For a leading confectionery producer, the challenge was clear: how to reliably and repeatably detect label alignment and confirm the presence of print markings on every carton, in real-time, without contact, and at production line speeds. Traditional methods often fell short, requiring manual intervention or failing to keep pace with modern production demands. The solution needed to offer:

• Reliable, repeatable in-line detection: Non-contact sensing capable of consistent performance.
• Real-time rejection: Immediately identify and remove unidentified or untraceable products.
• Remote set-up: Minimise the need for manual intervention on the factory floor.

The Solution: Photoelectric Contrast Sensors

The answer came in the form of a photoelectric contrast sensor from the Contrinex Cubic Small range. Here's how it works:

Strategic Placement: Immediately after the label printer-applicator, a single Contrinex Contrast sensor is mounted beside the conveyor. Its adjustable brackets allow for easy, precise positioning.

Advanced Detection: As each labelled carton passes the detection point, the sensor's single-lens autocollimator delivers a narrow optical beam. This allows for the detection of even the smallest features. The sensor intelligently selects the best emission colour (red, green, or blue LED light) during set-up, ensuring optimal contrast resolution against various label and carton materials.

Real-time Verification: Changes in contrast trigger the sensor. The transition from the carton surface to the label body identifies the position and alignment of the label itself. Crucially, the well-defined contrast between printed content and the label body ensures reliable detection of even the smallest print marks, such as batch codes or expiry dates.

Instant Rejection: If the label is wrongly aligned, blank, or print markings are missing, the sensor immediately triggers a reject mechanism. The defective carton is then diverted to a holding area for investigation, preventing untraceable products from progressing further down the line or reaching the customer.

By implementing intelligent sensing solutions like the Contrinex photoelectric contrast sensor, confectionery manufacturers in the UK can achieve high levels of accuracy and efficiency in their labelling processes. This not only safeguards product integrity and traceability but also contributes to significant cost savings by reducing waste and preventing costly errors.

For more information: 

plusautomation.co.uk

Tel: 0121 58 222 58