Time for robots to get their bearings

Industrial robots are deployed on the production line for their precision and repeatability. This means that every component inside these machines has to contribute to maintaining this precision, something that is often overlooked. Consider a six-axis robot as an example. These articulated robot arms require high levels of accuracy from their rotary joints to perform assembly processes correctly. Without the correct bearings, this precision cannot be maintained.

SMB Bearings has been supplying bearings for robotics for over 30 years and recommends that customers opt for thin section, stainless steel bearings in robotic applications. Because there is very little difference in size between the internal and external ring of these bearings, they do not drastically increase the weight of a robot and can therefore maintain the accuracy of the machine.

The whitepaper also advises on lubrication requirements for robot bearings. Due to the thinness of these bearings, the ring not only needs to be manufactured in such a way that ensures it is as round as possible but the shaft and housing should be made to the same levels of roundness to avoid distorting the bearing rings. To keep the ring continually running smoothly, a low viscosity grease is required as an overly sticky grease could increase the bearing torque to unacceptable levels.

The whitepaper also details a case study with the Shadow Robot Company, where SMB Bearings supplied specialist bearings to help create a grasping robot hand. The company supplied EZO bearings from Sapporo Precision for this project.

“These bearings were very easy to install in our Smart Grasping System,” explained Luke Moss, Robot Engineer at the Shadow Robot Company. “This is a direct result of the quality, tolerance of consistency of these bearings, something that is essential for repeated assembly and high precision across multiple robots.”

SMB Bearings is the official UK distributor of EZO Bearings from Sapporo Precision and often recommends this brands for robotic applications.

“The EZO range of thin section bearings is produced to an incredibly high standard,” explained Chris Johnson, Managing Director of SMB Bearings. “All bearing components are checked during the manufacturing process and every assembled bearing that comes off the EZO production line is individually tested. Any deficiencies are rejected. These high standards ensure that even the millionth bearing produced is as high quality as the first - with EZO, you will never get an ineffective bearing.”