When a well-known bearing manufacturer moved three independent grinding operations into one purpose built cell it created a justifiable need for a robotic machine unload system.

The cell comprised of three grinding operations, finish grind the outer ring faces, rough grinding of the outer ring outside diameter, and another centre-less grinding operation to finish the outside diameter.

Initially the cell was manually unloaded with the intention to automate at a later date but putting the cell together has enabled it to be fully automated from input on the first operation to output of the finish operation.

The engineering team trawled the robot systems houses and manufacturers to explain their need to place 10,000 components at an average weight of 0.75kgs and 50 different types to be handled over 16 hours per day into stillages.

The major problem was the use of a non-standard pallet, which has sides that taper inward and an overhang on the opening. This made the placing of the outer rings into layers more complex, most suppliers were able to work around this.

The problem was exacerbated when picking up separators to lay on top of each layer as to allow oil drainage a plastic lattice type separator is used which means vacuum pick-up was out of the question.

FANUC Robotics the chosen supplier specified a FANUC M420i robot to do the unloading and engineered a gripper to pick two rings at a time, gripping them internally to place them into the stillage. They also engineered a gripper to pick up a standard lattice separator as required and place it onto the layer of bearing cases. A standard auto tool changer system was specified to enable automatic changeover of grippers.

The M420i is FANUC's latest generation, high performance, high-speed robot that has a four axes 'arm' capable of lifting up to 40 kgs. The robot's large working area, which is the largest in its class with a reach of 1,855 mm, accommodates two stillages in the cell therefore allowing either to be changed without interrupting operations.

Overall the cell has provided many benefits but in particular running the grinding machines as a cell has enabled their utilisation to be greatly increased. The payoff has seen improved consistency on the finished diameter, which is machined within 10 microns.

Other advantages include the elimination of time consuming and expensive handling damage and the release of skilled operators from the mundane operations to the more productive setter operator tasks.

To improve production quality and reduce costs the benefits of this system is clear. As systems partners Micromech Robotics and Fanuc can specify, build and install the right equipment that is simple to programme and operate. Perhaps you are not already using a robot and this application has some bearing on you and you would like to find out more about our products and services then contact Stirling Morley on 01376 333311