100% fault detection on high-speed bottle crowning line
Integrating a user-friendly vision sensors into a multiple-product bottle crowning line provides a simple solution to fault detecting for leading Australian brewery.
Tooheys currently produces more than 300 million liters of beer annually from its Lidcombe-based brewery in Sydney’s west. Any company operating in a production critical industry on this scale knows just how damaging undetected product defects can be to business and understands the true value of an effective product defect inspection system. At Tooheys, two product lines running multiple bottled products are required to make frequent product changes – often in the course of a 24-hour period. With each product change requiring a change in bottle crown or cap incorrect bottle crowning can occur. Add to this a line speed running at 1200 bottles per minute and it is easy to see why a fast and reliable defect inspection solution was necessary to satisfy Tooheys’ stringent quality controls.
A high-tech solution for high-speed production
Machinery Automation & Robotics’ (MAR) approach to the bottle crowning inspection project at Tooheys was simple. Use advanced technology to create a user-friendly solution. The Cognex In-Sight® vision system was selected for its speed and interface ability, its capacity to detect defects in any 360-degree orientation and its robust design – the system undergoes regular wash downs. And the ability to make changes to the threshold determining acceptance of variable product qualities – detecting scratches, water blobs, misprints or print faults, for example – means that the defective product rejection accuracy rate of the Cognex In-Sight vision system is extremely high.
The vision system at work
Two Cognex In-Sight vision systems are installed on Tooheys’ AB2 bottling lines, each inspecting for correct crown placement on the product selected. Product selection itself is achieved simply via a touch screen/HMI. The camera is mounted on an adjustable post, specifically designed to allow for bottle height variations. Upon product selection the camera is simply moved up or down to maintain a camera focal length of 125mm from the top of the bottle crown. Along with the camera itself, the mounting bracket houses a DOAL lighting system, used to emit a red light on to the crowns. The red-cut lens cover filters out ambient light, resulting in a highly accurate image being captured by the camera.
All controls for the vision sensors are wired back to the line’s main electrical panel. Within the panel lies the power supply for the DOAL lighting system and the In-Sight cameras. The panel also houses the I/O module. This module interfaces with the vision sensor and the PLC, allowing product changes to be loaded into In-Sight and output changes to be relayed to the reject mechanism. Consequently, if an incorrect crown is detected the bottle is rejected further down the line via a delayed signal sent from the PLC. For ease, the cameras can be monitored via an Ethernet connection back to a local PC. Program changes can also be made at this point with the Cognex In-Sight Explorer software, making new product changes very simple.
Working together for independence
By adopting a strong teamwork approach to this project MAR has designed and engineered a vision sensor solution employing user-friendly software, which Tooheys is able to fully operate independently. Acting in an advisory capacity MAR provided assistance with the initial integration process enabling Tooheys’ staff to undertake the vision system installation autonomously. Comprehensive training provided to Tooheys’ staff by MAR on software installation, programming and modifications, bottle crown changeover processes, and basic operational procedures for the Cognex In-Sight vision system package has allowed Tooheys to undertake subsequent unit installations and programming.
Adding up the benefits
Addressing the issue of defect detection on high speed, multiple product production lines with a simple yet effective integrated vision system solution has provided Tooheys with many benefits including:
• An integrated vision system including electrical and mechanical design, software and functional design, vision I/O interface to PLC, installation, modification and on-line commissioning
• A user-friendly vision system solution and comprehensive training package enabling independent installation, programming and operation by the client
• An effective partnership of world-leading Cognex vision technology and MAR’s extensive vision system integration experience
• Expertise in lens, lighting and camera selections
• A robust and reliable vision system designed for high-speed lines
Technology at work for Tooheys
• The control system features a Siemens S7 PLC and uses software code and field sensors to detect product to be inspected by the vision sensors and provide relevant outputs to operate the reject mechanism
• Two high-speed outputs are standard with the vision system.
• The interface between the Cognex In-Sight cameras and the Siemens PLC is via a Cognex I/O module and a field cable link. The I/O module then inputs to the Siemens PLC in the same panel
• A single Cognex In-Sight camera inspects multiple defects in one image capture and recognition process at the above line speed
• The recognition tools available with the Cognex In-Sight system detect incorrect, damaged or misprinted bottle crowns in any 360-degree orientation at typical line speeds
• Custom selected lighting solutions provide adequate lighting for each inspection station and remove ambient light changes adversely affecting the visual inspection process
• The Cognex In-Sight vision system has a high wash down rating IP67