Tekpak Automation has increased production throughput by over 30% for a UK pharmaceutical manufacturer of transdermal patches, thanks to a robotic packaging system built around continuous machine vision, inspection and active tracking.
Tekpak Automation
Incorporating four Schneider Delta robots, the Tekpak QC-Sleever inspects, verifies, picks and packages patches at the client’s site at ultra-high speeds of up to 1,600 patches a minute, whilst reducing the reject rate to less than 1%. In doing so, Tekpak has enabled the customer to cut their labour costs considerably, thanks to a reduction of 12 operators per shift – as well as saving them over 30% in total footprint compared to a traditional multi-machine system.
Based in Wexford, Ireland, Tekpak Automation is renowned for its pick & place solutions and has over 25 years’ experience in designing, building and installing robotic solutions for food and pharma companies across the UK, Ireland, Europe and USA. When it was asked to devise an automated solution for faster inspection and packaging by a manufacturer of transdermal patches – medical adhesive strips applied to the skin for uses such as pain management, hormone therapy and smoking cessation – Tekpak’s team of innovators came up with the Quad Cell (QC)-Sleever.
The QC-Sleever comprises four main vision inspection stations. Two of these are located before the quad cell itself, integrated into the upstream patch manufacturing system. While one checks for the shape of the patch, the quality of the solution, and the presence of woven material and any foreign material, the other also inspects for the presence of the heat seal on the patches. This data is sent to the four downstream Delta robots located inside the quad cell, up to 6m away. The cell tracks defects from these vision systems and ensures the four Delta robots leave any defective patches on the main infeed belt, eventually ending up in the reject bin.
The other two inspection stations are housed within the quad cell itself. The first scans the position of the patches on the conveyor, reads the alpha-numeric data on the top of the patch, and verifies that it is of the correct batch. This data is then again sent to the four Delta robots located inside the cell, which either pick their allocated patches or leave the rejects on the conveyor to continue to a reject bin. Each robot handles 400 patches per minute, giving a combined throughput of 1,600 p/m.
Once the patches have been picked, they then undergo their final inspection. The robot presents the underside of the patches to a specialised UV-backlit camera for inspection of a number of metrics, including the concentricity of the patch contents relevant to the patch, the presence of any foreign material, the roundness of the patch, and the position of the gripper head on the patch itself.
Once the final vision inspection has been completed, the patches are either dropped into another reject bin or placed onto an outfeed conveyor by one of the robots. These outfeed conveyors bring the verified patches to the packing/sleeving section of the machine where they are counted and collated into groups of thirty using a bespoke collator and specific window sensor. The sleeving section of the machine opens the pillow-shaped sleeve, into which a leaflet and the patches are dispensed, before it is sealed using hot-melt glue and printed with the relevant batch data. Finally, the sleeve is verified before being conveyed down to a case-loading robot.
Delta robot technology is again employed in the case packing area. Groups of 10 sleeves are accumulated before a robot picks the group using a tailor-made gripper head. The group of sleeves are then placed into a large, corrugated case, which is tilted to allow the robot greater access. This is done using a pneumatic tilting device that also tilts back down to allow the insertion of layer cards between the layers of sleeves. Once the case has been filled, it is then sent to the outfeed for tape closing/labelling etc.
According to Darragh Sinnott, Tekpak’s technical director, the transdermal patches in question proved difficult to both inspect and package in an automated solution.
“The patches are made up of multiple layers and various materials,” explains Darragh. “The bottom layer is a paper-like material. On top of this is a woven mesh that is then encased in a wet solution which is poured over the pair, before the patch is sealed using a heat press. The quality of the patch is inspected upstream by two of our vision systems. This quality control was one of the client’s major requirements; in fact, each patch is subject to ten separate vision inspection jobs at a rate of 1,600 patches p/m before it is deemed to have met the required standards to be packed.”
As proof of the QC-Sleever’s superior performance, the return rate of unsatisfactory patches is now below 1%, more than meeting the client’s exacting demands.
Sinnott continues: “As well as maintaining quality control of the patches themselves and increasing throughput by a third, one of the most impressive features of the Tekpak QC-Sleever is its compact footprint. At the client’s manufacturing facility, it replaced a manual packing line that handled a much smaller throughput than the quad cell manages. Alongside this, similar multi-machine systems have much larger overall footprints, something that didn’t suit the client’s floorplan. In fact, the Tekpak QC-Sleever has saved the client over 30% in total footprint compared to a multi-machine system. This has also reduced the number of operators required on the line, with a saving of up to twelve operators per shift from the manual line, and up to six compared to a multi-machine system.”
For this pharmaceutical manufacturer, Tekpak’s automated inspection and packaging solution has more than met the brief – increasing output and improving quality control while saving space and reducing their labour burden.